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ESABASE2 - Framework Software User Manual

1. 119 5 Troubleshooting 120 5 1 Precautions 120 Date 2013 07 23 ESABASE2 Framework Revision 1 8 2 Software User Manual State Final Reference R077 230rep_01_08_02_Software_User_Manual_Framework doc Page 4 176 etamax space GmbH Frankfurter Str 3D 38122 Braunschweig 5 2 Trouble Information 120 5 3 Program Messages 121 5 3 1 Messages ESABASE2 121 5 3 2 Messages Eclipse and JVM 122 5 3 3 Messages Solver 122 5 4 Known Issues 124 5 4 1 Import of Complex BAS Files 124 5 4 2 Memory Leak caused by Open CASCADE 125 5 4 3 Meshing
2. 125 5 4 4 ATI Graphics Card 127 6 Annex A Geometry Shapes 128 6 1 Basic 3D Shapes 128 6 1 1 Box 129 6 1 2 Cone 132 6 1 3 Cylinder 135 6 1 4 Ellipsoid 138 6 1 5 Paraboloid 142 6 1 6 Sphere 146 6 2 Basic 2D Shapes 150 6 2 1 Disc 151 6 2 2 Plate
3. 107 Table 3 6 The pdir parameter 108 Table 3 7 The track parameter 109 Table 3 8 The inverse parameter 109 Table 5 9 Overview of the capabilities of the ESABASE2 meshers 127 Table 6 1 Definition of the BOX shape in ESABASE style 129 Table 6 2 Definition of the BOX shape in GDML style 130 Table 6 3 Definition of the CONE shape in ESABASE style 133 Table 6 4 Definition of the CONE shape in GDML style 133 Table 6 5 Definition of the CYLINDER shape in ESABASE style 136 Table 6 6 Definition of the CYLINDER shape in GDML style 136 Table 6 7 Definition of the ELLIPSOID shape in ESABASE style 139 Table 6 8 Definition of the ELLIPSOID shape GDML style 139 Table 6 9 Definition of the PARABOLOID shape 143 Tabl
4. 174 7 2 Geometry Editor Toolbar 176 Date 2013 07 23 ESABASE2 Framework Revision 1 8 2 Software User Manual State Final Reference R077 230rep_01_08_02_Software_User_Manual_Framework doc Page 6 176 etamax space GmbH Frankfurter Str 3D 38122 Braunschweig Document Information I Release Note Name Function Date Signature Established by K Ruhl K D Bunte A G de P Hake M Zaake J Weiland J Pervez A Miller M D ttmann Project Engineers 2013 07 23 Released by K D Bunte Project Manager 2013 04 23 II Revision History Version Date Initials Changed Reason for Revision 0 1 2009 06 12 KR All Taken over from ESABASE2 Debris SUM restruc tured chapters and rewrote introduction and get ting started chapters 0 2 2009 06 22 KR Chapter 3 Rewrote mission and S C handling 0 3 2009 07 06 KR Chapters 4 5 Annex A and B Rewrote debris meteoroids chapter troubleshoot ing section Annex A and B 0 4 2009 07 28 KR Chapter 2 3 4 Enhancements after PM5 0 5 2009 08 03 KR All Split into Framework Solver documents 0 9 2009 09 23 KB All Review for Final Draft 1 0 2009 09 28 KR All Adapted to review results 1 1 2009 10 22 KR KB Chapters 2 A User feedback recognition 1 2 2009 12 11 AG
5. 36 3 1 4 Mission Visualisation 37 3 1 5 Ground Track 38 3 1 6 Import of INP Files 39 3 1 7 Trajectory File 40 3 1 8 Orbit Propagator 42 3 2 Geometry 46 3 2 1 Geometry File 47 3 2 2 Geometry Viewing 48 3 2 3 Geometry Editing 53 3 2 4 Geometry Outline and Properties View 76 3 2 5 Boolean Operations 84 3 2 6 Geometry Model Import Interfaces 86 3 2 7 Geometry Model Ex
6. 171 Figure 6 28 Points of the four sided truss object 172 Figure 6 29 Additional parameters of the four sided truss object 172 Figure 7 1 ESABASE2 menu bar 174 Figure 7 2 ESABASE2 help system 175 Figure 7 3 Geometry editor Toolbar right side 176 Date 2013 07 23 ESABASE2 Framework Revision 1 8 2 Software User Manual State Final Reference R077 230rep_01_08_02_Software_User_Manual_Framework doc Page 14 176 etamax space GmbH Frankfurter Str 3D 38122 Braunschweig VIII List of Tables Table 2 1 Hardware Requirements 18 Table 3 1 Orbit input parameters 44 Table 3 2 Examples for Degree of Freedom specifications 100 Table 3 3 The Inherit parent values parameter 106 Table 3 4 The VEC1 parameter 107 Table 3 5 The VEC2 parameter
7. 153 Figure 6 15 Meshing parameters of the PLATE 154 Figure 6 16 Specific geometry shapes 155 Figure 6 17 Parameters of a prism object 157 Figure 6 18 Parameters of a surface object 159 Figure 6 19 Complex geometry shapes 161 Figure 6 20 Parameters of a beam object 162 Figure 6 21 Parameters of a pipe object 164 Figure 6 22 Parameters of a tank object 166 Figure 6 23 Meshing parameters of the tank 167 Figure 6 24 Overview of the truss object 169 Figure 6 25 Points of the truss object 169 Figure 6 26 Additional parameters of the truss object 170 Figure 6 27 Overview of the four sided truss object
8. 63 Figure 3 23 Material Overview Page Edit materials button 64 Figure 3 24 Material Editing Page 64 Figure 3 25 Material editing page Properties view 65 Figure 3 26 Material editing window Filter button 67 Figure 3 27 Material overview page select a material for all surfaces 68 Figure 3 28 Geometry editor example satellite with antenna dish at bottom 69 Figure 3 29 Geometry editor Pointing page antenna dish 70 Figure 3 30 Geometry editor Kinematic page antenna dish 71 Figure 3 31 Geometry editor Pointing page System node 72 Figure 3 32 Geometry editor Kinematic page solar panel 73 Figure 3 33 Geometry editor Pointing page solar panel 74 Figure 3 34 Geometry editor example satellite with two solar panels 75 Figure 3 35 Orbital point configurations example satellite 75 Figure 3 36 G
9. 85 Figure 3 48 The shape after the modification 86 Figure 3 49 Geometry file creation wizard STEP variant 87 Figure 3 50 Geometry editor imported STEP ATV model 88 Figure 3 51 Geometry file creation wizard BAS variant 89 Figure 3 52 Geometry editor imported HUBBLE BAS 90 Figure 3 53 Geometry file creation wizard GDML variant 91 Figure 3 54 Geometry file creation wizard STEP SPE variant 92 Figure 3 55 The ATV imported from a BAS file 93 Figure 3 56 The GDML export entry in the context menu 94 Figure 3 57 The directory for the export is selected 94 Figure 3 58 Files generated during GDML export 95 Figure 3 59 Typical content of mainFile gdml 95 Figure 3 60 A simple satellite structure to demonstrate the STEP SPE export 96 Figure 3 61 STEP S
10. 8 V Glossary 9 VI List of Abbreviations 9 VII List of Figures 10 VIII List of Tables 14 1 Introduction 16 1 1 The Big Picture 16 1 2 Chapter Overview 17 1 3 Problem Reporting 17 2 Getting Started with ESABASE2 18 2 1 Installation and Start 18 2 1 1 Hardware Requirements 18 2 1 2 Installation 19 2 1 3 Operating System Adaptations
11. 20 2 1 4 Upgrade 21 2 1 5 Starting ESABASE2 22 2 2 Basic GUI Usage 23 2 2 1 GUI Overview 23 2 2 2 GUI Adaptation 26 2 2 3 Project Organisation 27 3 Mission and Spacecraft Definition 31 3 1 Mission 31 3 1 1 Mission File 32 ESABASE2 Framework Date 2013 07 23 Software User Manual Revision 1 8 2 Reference R077 230rep_01_08_02_Software_User_Manual_Framework doc State Final etamax space GmbH Frankfurter Str 3D 38122 Braunschweig Page 3 176 3 1 2 Mission Editor 33 3 1 3 Mission Outline and Properties View
12. 153 6 3 Specific Shapes 155 6 3 1 Facet 156 6 3 2 Prism 157 6 3 3 Surface 159 6 4 Complex Shapes 161 6 4 1 Beam 162 6 4 2 Pipe 164 6 4 3 Tank 166 6 4 4 Truss 169 ESABASE2 Framework Date 2013 07 23 Software User Manual Revision 1 8 2 Reference R077 230rep_01_08_02_Software_User_Manual_Framework doc State Final etamax space GmbH Frankfurter Str 3D 38122 Braunschweig Page 5 176 7 Annex B Additional GUI Elements 174 7 1 Application Menubar
13. ESABASE2 Framework Date 2013 07 23 Software User Manual Revision 1 8 2 Reference R077 230rep_01_08_02_Software_User_Manual_Framework doc State Final etamax space GmbH Frankfurter Str 3D 38122 Braunschweig Page 59 176 Moreover you can choose the color of the shape The default is to color it according to ob ject number but you can override it with a fixed color here Finally you may check the orientation of the mesh elements by enabling Display Element Normals This will display a perpendicular arrow at the centre of each mesh element Close the Box wizard now by pressing Finish as we will now continue with a cone as a child to the box Date 2013 07 23 ESABASE2 Framework Revision 1 8 2 Software User Manual State Final Reference R077 230rep_01_08_02_Software_User_Manual_Framework doc Page 60 176 etamax space GmbH Frankfurter Str 3D 38122 Braunschweig 3 2 3 3 Cone Position and Attitude Page Each shape has its local coordinate system which is initially set to 0 0 0 within its parent s local coordinate system The Position and Attitude page allows you to arrange a shape within the coordinate system Normally you define the shape size without regard to placing it although for some shapes this would be possible You then move the shape along the XYZ axis of its local coordinate system translation and rotate it by specifying angles and axis priorities rotation
14. To further our example satellite mark the box in the 3D view by leftclicking it then rightclick to open the context menu and choose Coordinate Systems global coordinate system This will show the global coordinate system Rightclick the box again and choose Add Child Cone from the context menu On the wizards size page give the cone p1 0 0 0 and p2 0 30 0 complement it with diam1 80 and press Finish to preview the result The following figure shows that the cone is somewhat misplaced especially if seen from the front view circled in red Figure 3 19 Geometry editor default Cone To remedy the situation leftclick the cone to select it and then choose Modify Position and Attitude from the context menu This will directly jump to the Position and Attitude page in the Cone wizard as shown in the following figure ESABASE2 Framework Date 2013 07 23 Software User Manual Revision 1 8 2 Reference R077 230rep_01_08_02_Software_User_Manual_Framework doc State Final etamax space GmbH Frankfurter Str 3D 38122 Braunschweig Page 61 176 Figure 3 20 Geometry editor Cone wizard Position and Attitude page In the first row translate the shape by 140 50 50 mm Because X is the velocity direction of the satellite as indicated by the front viewing perspective this will move the cone to 4cm before the front plate and centre it in Y and Z direction In the rotation
15. Table 3 8 The inverse parameter If the pointing has two solutions the model should be visualised to determine whether the solution found is the desired one If not then the inverse parameter can be used to select the second solution Date 2013 07 23 ESABASE2 Framework Revision 1 8 2 Software User Manual State Final Reference R077 230rep_01_08_02_Software_User_Manual_Framework doc Page 110 176 etamax space GmbH Frankfurter Str 3D 38122 Braunschweig 3 4 3 Relationship with Mission Specification The pointing facility is related to the mission specified in the mission editor via Orbital definition of the articulated system Orientation of the bodies of the articulated system in space Since the attitude of each body is referenced to orbital specific directions such as the sun solar panels the earth antennas georelay antennas and the inertial direction tele scope the following is computed The system s position and the velocity which determines the orbital plane the veloc ity can be considered as a special pointing direction Sun ephemeris Earth ephemeris Georelay positions if any Eclipse 3 4 3 1 Orbit Definition The definition of the orbit is described in the ESABASE User Manual 6 The epoch is used to compute the position of the Sun the Earth as well as the location of possible georelay satel lites and to link the pointing facility with the ESABASE debris and meteo
16. 11 SPENVIS The Space Environment Information System orbit generator description http www spenvis oma be help models sapre_earth html ESABASE2 Framework Date 2013 07 23 Software User Manual Revision 1 8 2 Reference R077 230rep_01_08_02_Software_User_Manual_Framework doc State Final etamax space GmbH Frankfurter Str 3D 38122 Braunschweig Page 9 176 V Glossary Term Description Application ESABASE application such as e g the Debris or the Sunlight application Eclipse Eclipse is an open source community whose projects are focused on providing an extensible development platform and application frameworks for building software For de tailed information refer to http www eclipse org ESABASE Unix based analysis software for various space applications For details refer to the ESABASE User Manual 6 ESABASE2 New ESABASE version running on PC based Windows plat forms to be distinguished from the old Unix based ESABASE Geometric al analysis Analysis of a full geometric model Georelay Object pointing keyword tracking of a GEO satellite Non geometric al analysis Analysis of a plate faster than analysing a full geometrical model STEP Acronym which stands for the Standard for the Exchange of Product model data 8 VI List of Abbreviations Abbreviation Description GUI Graphical User Interface JVM Java Virtual Machine NASA National Astronautics a
17. etamax space GmbH ESABASE2 Framework Software User Manual Contract No 16852 02 NL JA Title PC Version of DEBRIS Impact Analysis Tool ESA Technical Officer G Drolshagen J S rensen Prime Contractor etamax space GmbH Authors K Ruhl K D Bunte A G de P Hake M Zaake J Weiland J Pervez A Miller Date 2013 07 23 Reference R077 230rep_01_08_02_Software_User_Manual_Framework doc Revision 1 8 2 Status Final Confidentiality Public etamax space GmbH Frankfurter Str 3d D 38122 Braunschweig Germany Tel 49 0 531 866688 33 Fax 49 0 531 866688 99 email esabase2 etamax de http www etamax de Date 2013 07 23 ESABASE2 Framework Revision 1 8 2 Software User Manual State Final Reference R077 230rep_01_08_02_Software_User_Manual_Framework doc Page 2 176 etamax space GmbH Frankfurter Str 3D 38122 Braunschweig Table of Contents Document Information 6 I Release Note 6 II Revision History 6 III Distribution List 7 IV List of References
18. gether to determine the final pointing of a spacecraft Pointing the Bodies and Indeterminacies How pointing works when pointing re quirements can only be partially fulfilled Pointing Output Describes the results of the pointing algorithm Pointing Calculation Method Describes the pointing algorithm 3 4 1 Pointing Introduction A system for example a spacecraft in orbit is subject to various environmental effects such as solar illumination the gravitational field the atmosphere and so on These effects appear as forces and torques which affect the orbital position and attitude of the system e g aerodynamic radiation effects or as material degradation e g surface recession due to the atomic oxygen fluence and depend strongly on the geometrical configuration of the system on its orbital orientation and on the orbital position and velocity of the system In order to compute these effects accurately the articulating capabilities of the bodies of the system have to be properly modelled For example an earth oriented system may assume a solar array articulating capability within angular constraints in order to track the direction of the sun With such a system changes in the solar panel orientation with respect to the ve locity vector and or the sun significantly alter the resulting effects e g torques forces sur face degradation on the system The orientation of the various bodies of an articulated system along an
19. Figure 6 4 Parameters of a cylinder object in ESABASE left and GDML right style 135 Figure 6 5 Meshing parameters of the cylinder 137 ESABASE2 Framework Date 2013 07 23 Software User Manual Revision 1 8 2 Reference R077 230rep_01_08_02_Software_User_Manual_Framework doc State Final etamax space GmbH Frankfurter Str 3D 38122 Braunschweig Page 13 176 Figure 6 6 Parameters of an ellipsoid object in ESABASE left and GMDL right style 138 Figure 6 7 Meshing parameters of the ellipsoid 141 Figure 6 8 Parameters of a paraboloid object 142 Figure 6 9 Meshing parameters and element numbering of the paraboloid 145 Figure 6 10 Parameters of a sphere object in ESABASE left and GDML right style 146 Figure 6 11 Meshing parameters of the sphere 149 Figure 6 12 Basic 2D geometry shapes 150 Figure 6 13 Parameters of a disc object 151 Figure 6 14 Parameters of a plate object
20. Framework Revision 1 8 2 Software User Manual State Final Reference R077 230rep_01_08_02_Software_User_Manual_Framework doc Page 92 176 etamax space GmbH Frankfurter Str 3D 38122 Braunschweig 3 2 6 4 STEP SPE File Import As of ESABASE2 version 5 0 0 the STEP SPE protocol is supported for import As most of the shape from the STEP SPE protocol can be mapped to the ESABASE2 shape palette it is pos sible to edit the shapes dimension after the import To import a STEP SPE geometry create a new geometry file by using the menubar choose File New Geometry The resulting wizard is shown in the following figure Figure 3 54 Geometry file creation wizard STEP SPE variant On the first page choose Import STEP SPE in place of the standard Create empty file Then on the next page choose the input STEP SPE file The third page will ask you for a directory location the same as for empty new geometries The NetGen mesher is stored as default for every object but it is also possible to use the OCC mesher or if the shape is part of the ESABASE2 shape palette also the ESABASE mesher ESABASE2 Framework Date 2013 07 23 Software User Manual Revision 1 8 2 Reference R077 230rep_01_08_02_Software_User_Manual_Framework doc State Final etamax space GmbH Frankfurter Str 3D 38122 Braunschweig Page 93 176 3 2 7 Geometry Model Export Interfaces 3 2 7 1 GDML Export As of ESABASE2 R
21. Note altitude of apogee apogee radius minus the celestial body s radius Re Earth 6378 165 km Moon 1738 km hper real 0 altitude of perigee km Note altitude of perigee perigee radius minus the celestial body s radius Re Earth 6378 165 km Moon 1738 km A real gt 6378 165 semi major axis km E real 0 e gt 1 eccentricity 0 1 incl real 0 001 INCL lt 180 orbital inclination deg raan real 0 RAAN lt 360 right ascension of the ascending node deg argper real 0 argper lt 360 argument of perigee deg trano real 0 trano lt 360 true anomaly at the mission start epoch deg Table 3 1 Orbit input parameters Please note that the specification of the perigee and apogee altitudes or alternatively of the semi major axis and the eccentricity can be used The input of any of the values results in a re calculation of the other values If the resulting orbit is not valid e g due to a perigee altitude below the Earth s surface the respective input field will be marked in red The parameters of the solar radiation pressure and the atmospheric drag can be modified in the respective Outline to consider the corresponding perturbations Please bear the follow ing definitions of the both parameters in mind These definitions are provided in 11 The solar radiation pressure parameter is defined as M A K Radiation Solar 8 10 451 0 _ where K is the material
22. 0 0 p2 0 0 20 diam 80 mm and thickness 2 mm Then translate it by 50 50 0 and rotate it by 180 0 0 The result is shown in the following figure Figure 3 28 Geometry editor example satellite with antenna dish at bottom On the figure the z axis of the parabole points down the x axis points into velocity direc tion and the y axis to the right side of the satellite With this in mind select the parabole and choose Modify Pointing from the context menu Date 2013 07 23 ESABASE2 Framework Revision 1 8 2 Software User Manual State Final Reference R077 230rep_01_08_02_Software_User_Manual_Framework doc Page 70 176 etamax space GmbH Frankfurter Str 3D 38122 Braunschweig The following figure shows the Pointing page for the parabole Figure 3 29 Geometry editor Pointing page antenna dish Set VEC 0 0 1 and direction EARTH Also activate the Inherit from parent check box this will allow the parabole to force the parent body to rotate if possible more on that in a minute In ESABASE2 all shapes possessing pointing must also have kinematics Although we do not wish to move the parabole the satellite should move instead it has to have at least mini mal kinematic freedoms Kinematic operates on the concept of an axis around which to move specified by a vector Perpendicular to this axis a second vector indicates where the 0 position is i e the natu ra
23. Another example would be The spacecraft altitude is greater than 2000 km Please use MASTER 2001 or 2005 for the debris analysis The reason is that MASTER 2001 and MASTER 2005 are the only debris models which support all orbits with altitudes up to 1000 km above GEO The other debris models are valid for orbital altitudes below 2000 km Generally the error messages should be self explaining so you can get an idea of what went wrong In case of doubt send us an email Date 2013 07 23 ESABASE2 Framework Revision 1 8 2 Software User Manual State Final Reference R077 230rep_01_08_02_Software_User_Manual_Framework doc Page 124 176 etamax space GmbH Frankfurter Str 3D 38122 Braunschweig 5 4 Known Issues The following issues are known as unresolved in ESABASE2 version 4 0 0 Import of complex BAS files Memory leak caused by Open Cascade 5 4 1 Import of Complex BAS Files If after the import of a complex BAS file not the entire geometric model is displayed in the 3D view or even nothing is shown this will most probably be caused by the use of complex BAS file constructs ESABASE language elements The following language elements from the original ESABASE are not available in ESABASE2 CONIC MIRROR NODE POLYNOM PYRAMID REMOVE REVOL SWEEP We recommend replacing the above mentioned shapes with the supported shapes in the BAS file while this is only a geometric approximation it will ens
24. By default both sides of the shape s boundary surface are active This default can be changed via the respective drop down menu on the Meshing page of the shape wizard 6 2 1 3 Meshing The meshing parameters are expressed along meshing directions a and b respectively These directions are shown in Figure 6 13 along with how the elements are numbered ESABASE2 Framework Date 2013 07 23 Software User Manual Revision 1 8 2 Reference R077 230rep_01_08_02_Software_User_Manual_Framework doc State Final etamax space GmbH Frankfurter Str 3D 38122 Braunschweig Page 153 176 6 2 2 Plate Figure 6 14 Parameters of a plate object 6 2 2 1 Purpose To describe the shape of a planar surface between a series of 3 to 64 points Parameter Type Unit Range Default Description p1 point mm mm mm First point of the plate pn point mm mm mm n th point of the plate Table 6 13 Definition of the PLATE shape Date 2013 07 23 ESABASE2 Framework Revision 1 8 2 Software User Manual State Final Reference R077 230rep_01_08_02_Software_User_Manual_Framework doc Page 154 176 etamax space GmbH Frankfurter Str 3D 38122 Braunschweig 6 2 2 2 Geometry and Size To describe the shape of a planar surface between a series of 3 to 64 points The boundary of the surface is constructed using the points in the order that they appear in the input The attributes must be in
25. ESABASE2 relies on the Eclipse RCP framework which in turn runs on a JVM Java Virtual Machine Although both have a clean exit strategy errors caused in the OpenCascade C part can lead to crashes The following figure shows an Eclipse JVM runtime error Figure 5 2 Troubleshooting Messages Eclipse and JVM abnormal termination It is not possible to recover from such an error Examine the log file from the logs directory to detect any warnings then restart the application It might be helpful to proceed with fewer files being open 5 3 3 Messages Solver A softer class of errors may appear within the solvers Many invalid data definitions for ex ample are detected and presented to you via error dialog Typical solver error messages are one of the following Pointing and kinematic When impossible kinematics and pointing combinations are detected Debris and other solvers When models are not specified for certain altitudes The following figure shows a solver error dialog ESABASE2 Framework Date 2013 07 23 Software User Manual Revision 1 8 2 Reference R077 230rep_01_08_02_Software_User_Manual_Framework doc State Final etamax space GmbH Frankfurter Str 3D 38122 Braunschweig Page 123 176 Figure 5 3 Troubleshooting Messages Solver warning kinematic In the example above a kinematic requirement can not be fulfilled because a degree of freedom is not available for an object
26. The intersection of this plane with the cone acts as the reference line for generating a segment and for specifying the direction of diame and also for specifying the starting point of the meshing into nodes and ele ments Note p3 must be speci fied if angle1 angle2 an gle3 or diame is specified angle1 real deg 0 lt angle1 lt an gle2 lt 360 0 Start angle with reference to the plane p1p2p3 for generating a segment angle2 real deg 0 lt angle1 lt an gle2 lt 360 360 End angle with reference to the plane p1p2p3 for generating a segment Table 6 3 Definition of the CONE shape in ESABASE style Parameter Type Unit Range Description rMin1 real mm 0 rMin1 lt rMax1 Inside radius at the base of the cone rMax1 real mm gt 0 Outside radius at the base of the cone rMin2 real mm 0 rMin2 lt rMax Inside radius at the apex of the cone rMax2 real mm 0 Outside radius at the apex of the cone sPhi real deg 0 sPhi 360 Starting angle of the segment in radians in the x y dimension dPhi real deg 0 lt dPhi 360 sPhi Delta angle of the segment in radians in the x y dimension dZ real mm gt 0 Half height of the cone in z direction Table 6 4 Definition of the CONE shape in GDML style 6 1 2 2 Geometry and Size This shape describes a circular cone or a segment of a cone The cone may be a volume or a surfa
27. comes a free axis which can be used by another body for a chained pointing realisation a typical case is given by the space telescope 3 4 4 2 Body with two Degrees of Freedom Indeterminacy This second indeterminacy case is illustrated by a simple example shown in Figure 3 66 the exact pointing is realised for two different bodies Figure 3 66 Attitude indeterminacy 2 degrees of freedom Physical constraints generally allow this indeterminacy to be suppressed but a special input command provided for each body allows one of the two solutions of a pointing with two degrees of freedom the Inverse flag to be chosen The best way to determine whether to use this parameter is to visualise the model The easiest way to visualise the pointing of the model is to perform an ESABASE2 run selecting the Only pre processing flag in the analysis run dialog 3 4 4 3 Kinematic Constraints in Pointing The previous sections have implicitly assumed that the relative rotations were unrestricted Generally a movable body cannot rotate 360 degrees because of the mechanical constraints of the joints and or due to the presence of other bodies The rotation of a body may be restricted by defining minimum and maximum angular posi tions with respect to its joint for each degree of freedom If satisfaction of the pointing re quirements for a body would require an angular position outside the allowed range the body is rotated to the closest limit and
28. mm mm mm Location of the centre of the circle at the base of the cylindrical mid section and the first point of the axis of revolution p2 point mm mm mm Location of the centre of the circle at the top of the cylindrical mid section and the second point of the axis of revolution defined by the vector p1p2 diam real mm gt 0 Outer diameter of the cylindrical mid section this parameter also specifies the diameter of the hemi spherical end caps thick real mm 0 lt thick lt diam 2 Wall thickness of the tank If thick 0 the shape is a surface Table 6 19 Definition of the TANK shape ESABASE2 Framework Date 2013 07 23 Software User Manual Revision 1 8 2 Reference R077 230rep_01_08_02_Software_User_Manual_Framework doc State Final etamax space GmbH Frankfurter Str 3D 38122 Braunschweig Page 167 176 6 4 3 2 Geometry and Size This shape describes a tank consisting of a cylindrical mid section capped by a hemisphere at each end The length of the mid section of the tank is determined by the distance p1 to p2 the wall thickness of the shape is determined by the thick parameter If thick 0 the shape will be a surface otherwise a volume Depending on the shape s parameter values a volume tank has an outer and inner base cap an outer and inner cylinder and an outer and inner top cap A surface tank has an outer base cap outer cylinder and outer top cap By de
29. p1p2 solid Wall thickness of the paraboloid If thick 0 the paraboloid is a surface shape ESABASE2 Framework Date 2013 07 23 Software User Manual Revision 1 8 2 Reference R077 230rep_01_08_02_Software_User_Manual_Framework doc State Final etamax space GmbH Frankfurter Str 3D 38122 Braunschweig Page 143 176 Parameter Type Unit Range Default Description h1 real mm gt 0 0 no trunca tion Location of the top of the parabol oid with respect to point p1 along the vector p1p2 used for generat ing a truncated paraboloid Note h1 may not be specified if diam1 is specified diam1 real mm 0 diam1 lt diam2 0 no trunca tion Diameter at the top of a truncated paraboloid Note diam1 may not be specified if h1 is specified h2 real mm gt 0 4000 Location of the base of the shape with respect to point p1 along the vector p1p2 Note h2 may not be specified if diam2 is specified diam2 real mm 0 diam1 lt diam2 equal to diam Diameter at the base of the paraboloid Note diam2 may not be specified if h2 is specified p3 point mm mm mm 0 0 0 Optional point defining the plane p1p2p3 The intersection of this plane with the paraboloid acts as the reference line for generating a segment and for specifying the direction of diame and also for specifying the starting point of the meshing into nodes and elements Note p3 must be specified
30. p1p2p3 and through the point p1 thick real mm 0 lt thick lt min diam 2 p1p2 0 Wall thickness of the el lipsoid type h1 real mm p1p2 h1 lt h2 p1p2 6000 Location of the base of the ellipsoid with respect to point p1 along the vec ESABASE2 Framework Date 2013 07 23 Software User Manual Revision 1 8 2 Reference R077 230rep_01_08_02_Software_User_Manual_Framework doc State Final etamax space GmbH Frankfurter Str 3D 38122 Braunschweig Page 139 176 Parameter Type Unit Range Default Description tor p1p2 h2 real mm p1p2 h1 lt h2 p1p2 6000 Location of the base of the ellipsoid with respect to point p1 along the vec tor p1p2 p3 point mm mm mm 0 0 0 Point defining the plane p1p2p3 The intersection of this plane with the el lipsoid acts as the refer ence for generating a sector and for specifying the direction of diame and also for specifying the starting point of the meshing into nodes and elements p3 must be specified if angle1 an gle2 or diame is speci fied angle1 real deg 0 lt angle1 lt angle2 lt 360 0 Start angle with reference to the plane p1p2p3 for generating a segment angle2 real deg 0 lt angle1 lt angle2 lt 360 360 End angle with reference to the plane p1p2p3 for generating a segment Table 6 7 Definition of the ELLIPSOID shape in ESABASE style Parameter Type Unit Ran
31. right side Mesh button 49 Figure 3 12 Geometry Editor in meshed view 50 Figure 3 13 Geometry editor Toolbar left side 51 Figure 3 14 Geometry editor example satellite 53 Figure 3 15 Geometry editor Box wizard Size page 55 Figure 3 16 Geometry editor Box wizard Meshing page 56 ESABASE2 Framework Date 2013 07 23 Software User Manual Revision 1 8 2 Reference R077 230rep_01_08_02_Software_User_Manual_Framework doc State Final etamax space GmbH Frankfurter Str 3D 38122 Braunschweig Page 11 176 Figure 3 17 Geometry editor Box wizard Meshing page Raytracing and sides 57 Figure 3 18 Geometry editor transparency set to 5 58 Figure 3 19 Geometry editor default Cone 60 Figure 3 20 Geometry editor Cone wizard Position and Attitude page 61 Figure 3 21 Geometry editor Wizard header 62 Figure 3 22 Geometry editor Material page
32. 3D 38122 Braunschweig Page 79 176 3 2 4 2 Copy amp Paste The major reason to become familiar with the Outline is the Copy amp Paste function It is per formed on the tree instead of the 3D model because positioning of shapes within the tree hierarchy can become a major issue if not properly observed To copy a shape for later pasting go the Outline and rightclick a shape name e g BOX or Solar Panel to open the context menu Then choose copy Both copy and paste actions are shown in the following figure Figure 3 39 Geometry editor Outline Copy amp Paste On the left screenshot the Paste menu entry is still disabled because no shape has been copied into the buffer clipboard yet The shape is directly selected and copied On the right screenshot the context menu has been opened on the parent element the Central body This is because the pasted object will be inserted as a child shape analo gous to Add child shape If you were to perform the paste directly on the copied node the pasted solar panel would appear as a child of the original solar panel not as a sibling After a paste operation the 3D view will not show any differences the reason is that the pasted shape overlays the original one Rightclick the new shape and choose Modify object from the context menu Then go to the Position and Attitude page to translate and rotate the new shape see 3 2 3 3 Date 2013 07 23 ESABAS
33. 3D geometry shapes ESABASE2 Framework Date 2013 07 23 Software User Manual Revision 1 8 2 Reference R077 230rep_01_08_02_Software_User_Manual_Framework doc State Final etamax space GmbH Frankfurter Str 3D 38122 Braunschweig Page 129 176 6 1 1 Box Figure 6 2 Parameters of a box object in ESABASE left and GDML right style 6 1 1 1 Purpose To describe the shape of a rectangular box Parameter Type Unit Range Default Description dx dy dz real mm mm mm gt 0 dx dy and dz are the lengths of the respective edges of the box along the x y and z axes thick real mm 0 lt thick lt min dx dy dz 2 solid box Thickness of the walls of the box If thick 0 the box is a surface shape with 6 connected faces Table 6 1 Definition of the BOX shape in ESABASE style Parameter Type Unit Range Default Description X Y Z real mm mm mm gt 0 X Y and Z are the half lengths of the respective edges of the box along the Date 2013 07 23 ESABASE2 Framework Revision 1 8 2 Software User Manual State Final Reference R077 230rep_01_08_02_Software_User_Manual_Framework doc Page 130 176 etamax space GmbH Frankfurter Str 3D 38122 Braunschweig Parameter Type Unit Range Default Description x y and z axes Table 6 2 Definition of the BOX shape in GDML style 6 1 1 2 Geometry and Size This shape describes a rectangular
34. BOX_DX attribute After the leftclick the right side screenshot shows a text field for the value You can enter any value here and press Re turn on the keyboard to make the change effective Please note that not all values may be editable for some attributes e g calculated ones this has been turned off since it would never make sense to edit them ESABASE2 Framework Date 2013 07 23 Software User Manual Revision 1 8 2 Reference R077 230rep_01_08_02_Software_User_Manual_Framework doc State Final etamax space GmbH Frankfurter Str 3D 38122 Braunschweig Page 83 176 3 2 4 5 Enclosures Shapes can be grouped into so called Enclosures Each enclosure group has a numerical id 1 2 3 and some applications e g Sunlight 5 can operate on the enclosures You can define enclosures only by using the properties editor as shown in the figure below and described in the previous subsection 3 2 4 4 Figure 3 43 Geometry editor Outline and Properties view Enclosure definition By default all shapes belong to enclosure 1 To change the id select the shape in the Out line navigate to the Info node and in the Properties view edit the value of ENCLOS Applications that do not know what enclosures are will ignore this parameter Please note that the Info node and the ENCLOS parameter will only be visible to you in the Expert mode to select Normal or Expert mode in the menu bar
35. Figure 6 7 along with how the elements are numbered ESABASE2 Framework Date 2013 07 23 Software User Manual Revision 1 8 2 Reference R077 230rep_01_08_02_Software_User_Manual_Framework doc State Final etamax space GmbH Frankfurter Str 3D 38122 Braunschweig Page 141 176 Figure 6 7 Meshing parameters of the ellipsoid Date 2013 07 23 ESABASE2 Framework Revision 1 8 2 Software User Manual State Final Reference R077 230rep_01_08_02_Software_User_Manual_Framework doc Page 142 176 etamax space GmbH Frankfurter Str 3D 38122 Braunschweig 6 1 5 Paraboloid Figure 6 8 Parameters of a paraboloid object 6 1 5 1 Purpose To describe the shape of a circular or elliptical paraboloid or a sector of a paraboloid Parameter Type Unit Range Default Description p1 point mm mm mm 0 3000 0 Origin of the shape and the first point of the axis of revolution p2 point mm mm mm 0 3000 0 Second point of the axis of revolu tion defined by the vector p1p2 Note p2 will be the focal point if diam is not specified diam real mm gt 0 4000 point p2 is the fo cus External diameter of the circular paraboloid or the external minor diameter of the elliptical parabol oid perpendicular to the plane p1p2p3 and through the point p2 Note If diam is not defined p2 will be the focal point thick real mm 0 lt thick lt min diam 2
36. GmbH Frankfurter Str 3D 38122 Braunschweig By default the complete boundary surface of the shape is active except if the shape has a fully enclosed cavity In this case only the positive side is active while the enclosed cavity is not present in surface node ray tracing analyses e g EASBASE THERMAL If the shape is a surface shape thick 0 or has a fully enclosed cavity this default can be changed via the respective drop down menu on the Meshing page of the shape wizard For a basic sphere in ESABASE style full sphere two parameters need to be specified Pa rameter p1 defines the centre point of the sphere and diam defines the diameter of the circular sphere Because no more parameters are defined the sphere will be full and com plete sphere For a basic sphere in GDML style only parameter rMax needs to be specified rMax defines the outer radius of the sphere By default the sphere is a solid sphere thick is empty To change this in ESABASE style the thickness of the walls of the sphere thick needs to be specified When the thickness is set to 0 the walls are infinitely thin When the thickness is defined diam is the external diameter of the circular sphere In GDML style the difference of rMax and rMin defines the thickness of the wall of the sphere In order to segment the sphere in ESABASE style p3 angle1 and angle2 have to be specified The point p3 together with p1 and p2 define the plane which serv
37. KR Chapters 3 5 Enclosures 3 2 4 BAS import 5 4 2 Surface nodes 3 2 3 2 orbital points 3 1 2 1 3 2011 02 03 PH All Update of the SUM to reflect the changes intro duced with release 4 of ESABASE2 1 4 2011 03 09 JW 3 2 3 4 Update of tutorial dealing with the Material Editor 1 4 2011 03 30 MZ 3 2 7 GDML export section added 1 5 2011 09 08 MD 3 1 5 Introduced chapter for Ground Track Page 1 6 2012 09 20 JP 3 2 7 5 4 3 Meshing info added 1 7 2013 04 04 PH AM 1 1 3 1 3 4 Added descriptions for Lunar Missions 1 8 2013 04 18 AM 3 1 8 3 4 3 Extended the descriptions for lunar missions 1 8 1 2013 06 11 AM 3 1 8 3 3 2 6 3 5 4 3 Include the definitions of SRP and drag SAPRE Note for GDML import internet connection Extended Meshing section 1 9 2013 07 23 MZ 3 2 3 2 Extended Meshing section ESABASE2 Framework Date 2013 07 23 Software User Manual Revision 1 8 2 Reference R077 230rep_01_08_02_Software_User_Manual_Framework doc State Final etamax space GmbH Frankfurter Str 3D 38122 Braunschweig Page 7 176 III Distribution List Institution Name Remarks ESTEC Gerhard Drolshagen Date 2013 07 23 ESABASE2 Framework Revision 1 8 2 Software User Manual State Final Reference R077 230rep_01_08_02_Software_User_Manual_Framework doc Page 8 176 etamax space GmbH Frankfurter Str 3D 38122 Braunschweig IV List of Refere
38. analysis and post processing purposes The calculations performed are described in the following subsubsections Initialisation part Activated only once at startup Dynamic part Activated at each orbital position The calculation steps are only treated in summary form followed by the formulas applied and any additional background information Date 2013 07 23 ESABASE2 Framework Revision 1 8 2 Software User Manual State Final Reference R077 230rep_01_08_02_Software_User_Manual_Framework doc Page 118 176 etamax space GmbH Frankfurter Str 3D 38122 Braunschweig 3 4 6 1 Initialisation Part The Kinematic section of the geometry file is read and the time related data is converted into modified Julian days The transformation matrices between the body reference frames and that of the central body which is identical to the system reference frame are computed With this information the orientation of the pointing vectors of the bodies in their initial posi tions are calculated in the reference frame of the central body The link vectors i e the vectors between the origins of two connected bodies are calcu lated and finally the bodies are translated so that the origins of their reference frames coin cide with the origin of the central body reference frame 3 4 6 2 Dynamic Part This part is performed for each of the orbital points selected according to the Pointing pa rameters contained in the g
39. and tesseral harmonics to include see KZONAL and KTESS below However sectoral harmonics are not included and may not be modelled These terms with the symmetry of the segments of an orange are often not important as during one com plete orbit around the earth the effects average to zero Thus in general only small perturba tions result with period no greater than one orbit But for a geosynchronous orbit which stays within a limited range of geographic longitudes this is not the case In fact the first sectoral harmonic J22 and K22 corresponding to the ellipticity of the equator is the major perturbing influence for a geostationary satellite producing an oscillation about two stable points in the equatorial plane with a period greater than 780 days SAPRE entirely neglects this effect However for runs of no more than a few days the results will be a fair approxi mation There is no sectoral harmonics restriction for the lunar orbits Date 2013 07 23 ESABASE2 Framework Revision 1 8 2 Software User Manual State Final Reference R077 230rep_01_08_02_Software_User_Manual_Framework doc Page 44 176 etamax space GmbH Frankfurter Str 3D 38122 Braunschweig 3 1 8 3 Input Parameters for SAPRE The following table provides an overview of the orbital parameters used to specify the orbit of the spacecraft as seen by the SAPRE orbit propagator Parameter Type Range Description hapo real 0 altitude of apogee km
40. button is to minimise the view the second one is to maximise it You can also maximise a view by double clicking its name tab left By double clicking the tab of an already maximised view the size is normalised You can also grab the tab and move the view around and snap it into different positions within the main window This includes tabbing views i e layering several views on top of each other Lastly the edges of each view can be grabbed for resizing Depending on the position of the view in the main window only the view or a whole column is resized All of your changes are saved automatically in the current perspective arrangement of views To reset the perspective to the original settings choose Window Reset Perspec tive in the menubar ESABASE2 Framework Date 2013 07 23 Software User Manual Revision 1 8 2 Reference R077 230rep_01_08_02_Software_User_Manual_Framework doc State Final etamax space GmbH Frankfurter Str 3D 38122 Braunschweig Page 27 176 2 2 3 Project Organisation In order to work with ESABASE2 you will work with input and output files Both are organ ised in projects This subsection deals with the following cases Creating a project Creating input files e g mission spacecraft Moving files around 2 2 3 1 Creating a Project The first thing to do after starting ESABASE2 is to create a new project which will contain S C geometry orbit and solver paramete
41. choose Window Preferences ESABASE2 Date 2013 07 23 ESABASE2 Framework Revision 1 8 2 Software User Manual State Final Reference R077 230rep_01_08_02_Software_User_Manual_Framework doc Page 84 176 etamax space GmbH Frankfurter Str 3D 38122 Braunschweig 3 2 5 Boolean Operations The starting point of a Boolean Operation is two overlapping 3D objects 10 The available Boolean Operations which can be performed are Intersection Union and Subtraction The following graphic depicts a cone which has a sphere as child shape Figure 3 44 Geometry editor Outline and Properties view Enclosure definition To perform a Boolean Operation select the child shape in the outline and open the context menu The menu will display the three different BO ESABASE2 Framework Date 2013 07 23 Software User Manual Revision 1 8 2 Reference R077 230rep_01_08_02_Software_User_Manual_Framework doc State Final etamax space GmbH Frankfurter Str 3D 38122 Braunschweig Page 85 176 Figure 3 45 The context menu in the outline containing the BO Select Intersect The editor now displays the result of this operation Figure 3 46 The shape after performing the operation It is important to know that the resulting shape takes all secondary attributes like shielding or material settings from the parent node Let us assume that we are not satisfied with the result and that we would like
42. file with the ending trajectory An example file is displayed in Figure 3 7 Figure 3 7 Trajectory File You can create this file via the context menu of a project or folder within a project New gt Other gt File then press Next and enter a name for the file e g trans fer trajectory Please note that the file must have the appropriate extension other wise it will not be recognized by the Analysis Wizard and cannot be chosen for an analysis It is also possible to create and edit the file with the text editor you prefer to save the file to disk with this editor and use drag and drop to move it into the folder of your ESABASE2 pro ject in the ESABASE2 explorer Certain syntax must be matched in order to allow ESABASE2 to use the file for an analysis Origin The origin defines the central body from which the mission specified by the trajectory file originates It can be omitted and if you do this the default value Earth is used internally The second valid option is to define it and to use either Earth or Moon Target Like origin Earth and Moon are viable options but unlike the origin pa rameter this parameter has to be specified Coordinates It is necessary to define the coordinate system used for the supplied state vectors ECI and LCI can be chosen ESABASE2 Framework Date 2013 07 23 Software User Manual Revision 1 8 2 Reference R077 230rep
43. in Table 2 1 are met Otherwise large geometries or analysis runs with a large number of or bital points could take very long or fail due to insufficient memory Minimum Recommended Operating System Windows 2000 Windows XP Vista RAM 1 GByte 4 GBytes Free Disk Space 1 GByte 2 GBytes CPU Clock frequency 2 GHz single core 2 GHz dual core Graphics Card Nvidia Geforce 6200 Nvidia Geforce 9800 Table 2 1 Hardware Requirements ESABASE2 Framework Date 2013 07 23 Software User Manual Revision 1 8 2 Reference R077 230rep_01_08_02_Software_User_Manual_Framework doc State Final etamax space GmbH Frankfurter Str 3D 38122 Braunschweig Page 19 176 2 1 2 Installation To install ESABASE2 unzip the ESABASE2_4 0 0 zip archive from the installation DVD to a loca tion of your choice We recommend deactivating anti virus software as its file scanning ac tivities can considerably slow down the unpacking process If you open a Windows Explorer and navigate to the ESABASE2 application directory the layout shown in the following figure will be presented to you Figure 2 1 ESABASE2 directory tree In the logs folder you can find the application log files named with application start date useful for troubleshooting If you report a problem to the etamax team please attach the pertinent log file In case you are an original ESABASE expert the contents of the Solver directory could be of inter
44. limitations We start with the mission editor Date 2013 07 23 ESABASE2 Framework Revision 1 8 2 Software User Manual State Final Reference R077 230rep_01_08_02_Software_User_Manual_Framework doc Page 32 176 etamax space GmbH Frankfurter Str 3D 38122 Braunschweig 3 1 1 Mission File With the creation of a project a new mission file has been created however you might also want to create a new one To do so choose File New Mission in the menubar A wiz ard as shown in the following figure will be opened Figure 3 1 Mission file creation wizard On the first wizard page Create empty file is selected as default just press the Next but ton The second page asks you for the location of the new file in the figure above tc_5_01 and a file name above cubesat_mission Upon pressing Finish a new mission file is created It has the file ending mission which is not shown in the ESABASE2 Explorer and does not need to be specified in the wizard A mission editor is automatically opened on the newly created file ESABASE2 Framework Date 2013 07 23 Software User Manual Revision 1 8 2 Reference R077 230rep_01_08_02_Software_User_Manual_Framework doc State Final etamax space GmbH Frankfurter Str 3D 38122 Braunschweig Page 33 176 3 1 2 Mission Editor If the mission editor is not already open go to the ESABASE2 Explorer view and doubleclick the missio
45. ometry had not been meshed it will use the OCC mesher internally to generate a mesh which can be exported Please note that this mesh is not stored within the file It will only be generated on the fly and removed after the export In the current implementation all shapes from the ESABASE2 shape palette can be exported to STEP SPE and all unknown shape types like imports from STEP AP can also be ex ported It is not possible to export assemblies 3 2 7 3 STEP AP Export With release 5 0 of ESABASE2 it is possible to export geometry objects to files following the STEP AP protocol The export mechanism for STEP AP follows the same principles as the GDML export de scribed in section 3 2 7 1 We can revisit the ATV example used to show the GDML export to show how the export works in detail After importing the BAS file go to the outline and select the System node Please note that the STEP AP export is only possible on system level and not for single shapes Date 2013 07 23 ESABASE2 Framework Revision 1 8 2 Software User Manual State Final Reference R077 230rep_01_08_02_Software_User_Manual_Framework doc Page 98 176 etamax space GmbH Frankfurter Str 3D 38122 Braunschweig Figure 3 62 STEP export in the outline After selecting the entry a new window opens where you can enter the name and the loca tion of the file which will be created to contain the geometry description in the STEP AP pro tocol
46. orbital trajectory is computed by the ESABASE2 pointing facility The pointing facility computes the best possible pointing of each body of a configuration of an articulated system to be oriented in its re quired pointing direction starting with the central body Data for the pointing facility is specified via the Kinematic and Pointing pages of the shape wizards within the geometry editor ESABASE2 Framework Date 2013 07 23 Software User Manual Revision 1 8 2 Reference R077 230rep_01_08_02_Software_User_Manual_Framework doc State Final etamax space GmbH Frankfurter Str 3D 38122 Braunschweig Page 103 176 The articulated system is modelled as a set of rigid bodies It consists of a central body sup porting other bodies as shown in the following figure Figure 3 63 Spacecraft model The bodies are hierarchically linked each body imparts its own movement to the bodies that are attached to it Each body is attached to another body through a joint with 0 1 or 2 rota tional degrees of freedom that are used by the pointing facility to orientate the body in the manner required Constraints may be specified on the degrees of freedom representing the rotational constraints of real joints The orbit of the articulated system is specified via the mission editor see 3 2 3 by means of the orbital elements and the corresponding mission start epoch The pointing direction of a body in space can be described in a
47. parameter K 1 gamma rho plate ESABASE2 Framework Date 2013 07 23 Software User Manual Revision 1 8 2 Reference R077 230rep_01_08_02_Software_User_Manual_Framework doc State Final etamax space GmbH Frankfurter Str 3D 38122 Braunschweig Page 45 176 K 1 gamma sphere K 2 plate with perfect specular reflection K 1 sphere with perfect specular reflection or perfect absorption K 1 44 sphere with perfect diffuse reflection rho and gamma are the reflectivity and the transitivity of the satellite A m is the total reflectivity area of the object for the spherical satellites it is the cross sectional area M kg is the mass of the satellite The atmospheric drag parameter is defined as M A c Drag c Atmospheri D 6 10 5 0 _ Where cD is the drag coefficient A m is the cross sectional area of the satellite and M kg is the mass of the satellite Date 2013 07 23 ESABASE2 Framework Revision 1 8 2 Software User Manual State Final Reference R077 230rep_01_08_02_Software_User_Manual_Framework doc Page 46 176 etamax space GmbH Frankfurter Str 3D 38122 Braunschweig 3 2 Geometry A spacecraft geometry model is prerequisite for a full analysis This section describes how you can build a geometry in a CAD way using the geometry editor It is structured into the following subsections Geometry File How to create a new geometry Ge
48. pointing Please note that for some complex BAS geometries some open issues exist refer to section 5 4 1 for more details ESABASE2 Framework Date 2013 07 23 Software User Manual Revision 1 8 2 Reference R077 230rep_01_08_02_Software_User_Manual_Framework doc State Final etamax space GmbH Frankfurter Str 3D 38122 Braunschweig Page 91 176 3 2 6 3 GDML File Import As of ESABASE2 version 5 0 0 the GDML protocol is supported for import As most of the shape from the GDML protocol can be mapped to the ESABASE2 shape palette it is possible to edit the shapes dimension after the import To import a GDML geometry create a new geometry file by using the menubar choose File New Geometry The resulting wizard is shown in the following figure Figure 3 53 Geometry file creation wizard GDML variant On the first page choose Import GDML in place of the standard Create empty file Then on the next page choose the input GDML file The third page will ask you for a directory location the same as for empty new geometries The NetGen mesher is stored as default for every object but it is also possible to use the OCC mesher or if the shape is part of the ESABASE2 shape palette also the ESABASE mesher Please note that for the GDML import an internet connection is required due to the needed retrieval of the GDML schema from the website defined in the GDML file Date 2013 07 23 ESABASE2
49. remains there until a position within the allowed range is specified Date 2013 07 23 ESABASE2 Framework Revision 1 8 2 Software User Manual State Final Reference R077 230rep_01_08_02_Software_User_Manual_Framework doc Page 116 176 etamax space GmbH Frankfurter Str 3D 38122 Braunschweig In some cases if the constraints have not been correctly defined the bodies may overlap one another These cases cannot be detected by the software Again this can only be de tected using visualisation 3 4 5 Pointing Output The pointing facility calculates the orientation of the pointing vector which has the minimum angular deviation from the specified direction for the bodies of the system for each of the selected orbital positions of the mission The results of the calculations are output to the results and listing files while the information content is the same For each kinematic step the Pointing Facility outputs the following information to the report file LISKIN which is written to the ListingFiles folder The report file can also be ac cessed through the Listings page of the results editor choose the Kinematic listing A kinematic listing contains the following date time and elapsed time from the beginning of an orbital sequence orbit information orbital elements state vector and sun location given in the inertial GAMMA 50 reference frame orientation of the pointing vector and the pointing d
50. section below keep angles and a XYZ rotation order then choose angle 3 z angle 270 Click Finish to view the results as shown above in the before and af ter screen shots Please note the checkbox for the local coordinate system If this is selected the local coordi nate system for that object will be displayed within the editor Date 2013 07 23 ESABASE2 Framework Revision 1 8 2 Software User Manual State Final Reference R077 230rep_01_08_02_Software_User_Manual_Framework doc Page 62 176 etamax space GmbH Frankfurter Str 3D 38122 Braunschweig 3 2 3 4 Cone Material Page We skip the Kinematic and Pointing pages see subsections 3 3 and 3 4 and concern our selves with material properties which always apply to surfaces not to bodies i e no bodies filled with aluminium here Since we need surfaces we have to mesh the geometry first Press the mesh button so that each object of the geometry will be meshed with the configured mesher and surfaces will be generated For our cone choose Modify Cone Size Although size pages differ from shape to shape all will contain a Thickness parameter of some kind Choose thickness 3mm Open the material editor page by clicking the Material link highlighted with a gray shadow in Figure 3 21 Figure 3 21 Geometry editor Wizard header The resulting material overview page will in turn look like the following illustrat
51. section of the truss and one of the sides will be per pendicular to the plane Table 6 20 Definition of the TRUSS3 shape ESABASE2 Framework Date 2013 07 23 Software User Manual Revision 1 8 2 Reference R077 230rep_01_08_02_Software_User_Manual_Framework doc State Final etamax space GmbH Frankfurter Str 3D 38122 Braunschweig Page 171 176 6 4 4 1 2 Geometry and Size This shape described a connecting truss whose cross section is an equilateral triangle with the centres of the ends located at points p1 and p2 Additionally a third point p3 may be specified to define the orientation of the truss The lengths of the sides may be specified by the size parameter if size 0 the truss is a line segment The number of elementary sections is specified by the nstep parameter The TRUSS3 is classed as a line shape and hence has no surface nodes It is not considered in surface related analyses 6 4 4 1 3 Meshing A meshing parameter cannot be applied to a TRUSS3 6 4 4 2 Truss4 Figure 6 27 Overview of the four sided truss object Date 2013 07 23 ESABASE2 Framework Revision 1 8 2 Software User Manual State Final Reference R077 230rep_01_08_02_Software_User_Manual_Framework doc Page 172 176 etamax space GmbH Frankfurter Str 3D 38122 Braunschweig Figure 6 28 Points of the four sided truss object Figure 6 29 Additional parameters of the four sided truss object 6
52. selected this button allows the filtering of the properties view see Figure 3 26 Not all properties of a material are useful for a certain solver e g the Atmos phere Ionosphere solver only uses the properties Accomo Omega Reacto and Speco Using the filter you can easily see which properties are used for each solver Figure 3 26 Material editing window Filter button Now that we know each control element in the Material Editing Window we can copy the ALUMINUM material into our geometry by selection the material and using the Copy to button Notice that the element Aluminum was copied as well since the material refer ences it as a fraction When you close the Material Editing Window by clicking close at the bottom you will now see that the material ALUMINUM appears in the Material overview list As indicated in the list it is already usable for COMOVA analyses and for GDML export To assign the material to all of the cone s surfaces select the Whole Shape option in the Assign materials section and select the material in the combo box see Figure 3 27 Press ing Finish will result in the storage of the material in the geometry file and the final as signment of the material to the surfaces If you re open the material editor for the Cone again you will see that each surface has the material ALUMINUM Furthermore the material overview shows that ALU
53. should point to the sun using the freedoms afforded by the kinematics The Pointing page is illus trated in the following figure Figure 3 33 Geometry editor Pointing page solar panel Following the 0 kinematic vector specified above choose the x axis to point to the sun set VEC1 1 0 0 and direction SUN Then Finish the wizard To complete the solar panel select the cylinder and choose Add Child Box from the con text menu Set the size to 20 100 400 and translate it by 10 30 200 The latter will move the box to the end of the cylinder in y direction and centre it x and z wise Please note that the front flat side of the box points along the x axis of the cylinder and therefore matches our pointing direction For better result accuracy go to the Meshing page of the solar panel box There set number of elements for b axis 4 and c axis 16 Select the solar panel box again in the 3D view to see the new meshing ESABASE2 Framework Date 2013 07 23 Software User Manual Revision 1 8 2 Reference R077 230rep_01_08_02_Software_User_Manual_Framework doc State Final etamax space GmbH Frankfurter Str 3D 38122 Braunschweig Page 75 176 Now repeat the process on the right side of the satellite You might consider using the Copy amp Paste functions in the Outline explained in subsection 3 2 4 The result should be similar to the figure below Figure 3 34 Geometry editor ex
54. system x y z To allow for more realistic modelling of the pointing behaviour of the various bodies a time notion has been introduced for each pointing direction Date 2013 07 23 ESABASE2 Framework Revision 1 8 2 Software User Manual State Final Reference R077 230rep_01_08_02_Software_User_Manual_Framework doc Page 112 176 etamax space GmbH Frankfurter Str 3D 38122 Braunschweig There are three ways of specifying the pointing of a body as one pointing vector and one direction for all orbital positions of the body e g the sun pointing of a solar array as several pointing vectors and or several pointing directions each pair valid for a given period of time e g different targets for a space telescope not yet available in ESABASE2 as pointing directions for one pointing vector where the pointing directions are speci fied in an external file e g a tracking antenna not yet available in ESABASE2 In addition to these facilities certain other pointing features can be modelled for the Earth orbits The pointing of a body can be directed towards a georelay spacecraft by specifying a georelay longitude The pointing of a body can be fixed for a given period of time such that o for the central body the orientation does not change with respect to the GAMMA 50 reference frame not yet available in ESABASE2 o for other bodies the orientation of the body is fixed with respect to its parent
55. the pointing behaviour of other parts of the system via the Outline or via the 3D editor right click on the object to be pointed select Modify object from the context menu go to the Kinematic page and specify the required degrees of free dom rotation axis axes and their restrictions go to the Pointing page and specify the intended pointing direction Note that all child objects of an articulated object will be oriented like their parent object unless a different pointing is specified for parts of the geometry sub tree or single objects which themselves have no child objects This section is structured into the following subsections Bodies Explains how shapes are connected to each other Degrees of Freedom Discusses the maximum allowed movement for bodies Central Body How kinematics applies to the central body Articulated Bodies How kinematics applies to non central bodies Date 2013 07 23 ESABASE2 Framework Revision 1 8 2 Software User Manual State Final Reference R077 230rep_01_08_02_Software_User_Manual_Framework doc Page 100 176 etamax space GmbH Frankfurter Str 3D 38122 Braunschweig 3 3 1 Bodies Each body except the central body is attached to another body the so called parent body A body can only be attached to one parent body but a parent body can have more than one body attached to it All bodies are connected to the central body either attached directly or linked
56. the same plane The shape has two faces top positive side and base By default both sides of the shape s boundary surface are active This default can be changed via the respective drop down menu on the Meshing page of the shape wizard 6 2 2 3 Meshing The meshing parameters are expressed along meshing directions a and b respectively These directions are shown in Figure 6 15 along with how the elements are numbered Figure 6 15 Meshing parameters of the PLATE ESABASE2 Framework Date 2013 07 23 Software User Manual Revision 1 8 2 Reference R077 230rep_01_08_02_Software_User_Manual_Framework doc State Final etamax space GmbH Frankfurter Str 3D 38122 Braunschweig Page 155 176 6 3 Specific Shapes Specific shapes are based on the concept of a Facet a free form point list in space which is then further extended and encompass both 2D and 3D shapes The following specific shapes are based on one ore more facets two dimensional dummy shapes Prism Surface The figure below gives a visual index Figure 6 16 Specific geometry shapes Facets will also be explained below Date 2013 07 23 ESABASE2 Framework Revision 1 8 2 Software User Manual State Final Reference R077 230rep_01_08_02_Software_User_Manual_Framework doc Page 156 176 etamax space GmbH Frankfurter Str 3D 38122 Braunschweig 6 3 1 Facet The facet is a so called dummy shape It ca
57. through other bodies Therefore the orbital position of the whole system is given when the orbital position of the central body is specified Each body is attached to its parent body through a hinge with 0 1 or 2 rotational degrees of freedom that are used by the pointing facility to orientate the body in the manner required For the central body the body reference frame is the same as the system reference frame The orbital position of the system is the position of the origin of the central body reference frame The body reference frame of an articulated body is the object reference frame of the first object of that body i e of the one for which the kinematic and pointing is specified 3 3 2 Degrees of Freedom The central body has 3 degrees of freedom When one pointing vector and direction is specified for the central body then the central body has one degree of freedom remaining namely rotation about that pointing vector Specifying one additional pointing vector fully determines the orientation of the central body in space An articulated body may have 0 1 or 2 rotational degrees of freedom DoF for example Degrees of Freedom DoF Properties Example 0 no relative motion i e rigidly connected 1 solar array radiator 2 antenna Table 3 2 Examples for Degree of Freedom specifications If satisfaction of the pointing requirements for a body would require an angular position out side the allowed range th
58. to decrease the radius of the sphere This can be done via the outline There we find a node called BOP under the CONE object Under the BOP node we find a node called OBJECT_1_1 This is the sphere which was used as second operand in the BO Figure 3 47 Modifying a BO via the outline Date 2013 07 23 ESABASE2 Framework Revision 1 8 2 Software User Manual State Final Reference R077 230rep_01_08_02_Software_User_Manual_Framework doc Page 86 176 etamax space GmbH Frankfurter Str 3D 38122 Braunschweig We select Modify Object The shape wizard opens There we decrease the radius of the sphere and press Finish The result is depicted next Figure 3 48 The shape after the modification The other BO can be used in a similar way BO can be chained so it is possible to apply the next BO to this shape now by adding another child object and perform the operation in iden tical manner To undo a BO one can select the second operand node of the BO under the BOP node open the context menu and choose Undo Boolean Operation This restores the parent ob ject and the child object is deleted If no more nodes are under the BOP node this node is deleted also 3 2 6 Geometry Model Import Interfaces The ESABASE application offers four different possibilities to import geometries STEP File Import The STEP file format is an industry standard for exchanging data in files 7
59. variety of reference frames Inertial reference frames Sun based reference frames Earth based reference frames Orbit related reference frames A body can also track a geo relay satellite The objective of the pointing facility is to orientate each body of a configuration of an articu lated system for a given orbit in its required pointing direction starting with the pointing of the central body For each degree of freedom of each body a pointing vector a vector always fixed relative to the body and a pointing direction the direction in space which the pointing vector is re quired to receive are defined Date 2013 07 23 ESABASE2 Framework Revision 1 8 2 Software User Manual State Final Reference R077 230rep_01_08_02_Software_User_Manual_Framework doc Page 104 176 etamax space GmbH Frankfurter Str 3D 38122 Braunschweig The degrees of freedom and their constraints do not always allow the required pointing di rection to be achieved On such occasions the pointing facility gives the orientation of the pointing vector which has the minimum angular deviation taking the constraints into ac count to the required direction 3 4 2 Pointing Parameters This subsection describes how to apply pointing to a spacecraft geometry it is divided into the following subsubsections General Aspects Things to know before considering the following pointing parame ters Inherit Parent Values The p
60. 013 07 23 Software User Manual Revision 1 8 2 Reference R077 230rep_01_08_02_Software_User_Manual_Framework doc State Final etamax space GmbH Frankfurter Str 3D 38122 Braunschweig Page 169 176 6 4 4 Truss Two types of truss shapes are available the three sided truss Truss3 and the four sided truss Truss4 6 4 4 1 Truss3 Figure 6 24 Overview of the truss object Figure 6 25 Points of the truss object Date 2013 07 23 ESABASE2 Framework Revision 1 8 2 Software User Manual State Final Reference R077 230rep_01_08_02_Software_User_Manual_Framework doc Page 170 176 etamax space GmbH Frankfurter Str 3D 38122 Braunschweig Figure 6 26 Additional parameters of the truss object 6 4 4 1 1 Purpose To describe the shape of a triangular section connecting truss Parameter Type Unit Range Default Description p1 point mm mm mm Location of the centre of one end of the truss p2 point mm mm mm Location of the other end of the truss size real mm gt 0 Length of the sides of the truss Note If size O the truss is treated as a line segment nstep int 1 nstep 50 Number of elementary sections that the shape is constructed of p3 point mm mm mm Point defining the plane p1p2p3 This point defines the reference plane for orientating the truss This plane will bisect the angle at one of the corners of the trian gular cross
61. 4 4 2 1 Purpose To describe the shape of a rectangular section connecting truss Parameter Type Unit Range Default Description p1 point mm mm mm Location of the centre of one end of the truss p2 point mm mm mm Location of the other end of the truss ESABASE2 Framework Date 2013 07 23 Software User Manual Revision 1 8 2 Reference R077 230rep_01_08_02_Software_User_Manual_Framework doc State Final etamax space GmbH Frankfurter Str 3D 38122 Braunschweig Page 173 176 Parameter Type Unit Range Default Description size1 real mm gt 0 Length of one side of the cross section of the truss Note If size1 0 the truss is treated as a line segment nstep int 1 nstep 50 Number of elementary sections that the shape is constructed of p3 opt point mm mm mm Point defining the plane p1p2p3 This point defines the reference plane for orientating the truss This plane will be parallel to the side of the truss whose length is indicated by size1 size2 opt real mm gt 0 size2 size1 square cross section Length of the other side of the cross section of the truss per pendicular to the other side and to the plane p1p2p3 Table 6 21 Definition of the TRUSS4 shape 6 4 4 2 2 Geometry and Size In order to define a truss4 which is a connecting truss whose cross section is a rectangular you must first specify two points p1 and p2 defined as coo
62. 77 230rep_01_08_02_Software_User_Manual_Framework doc Page 66 176 etamax space GmbH Frankfurter Str 3D 38122 Braunschweig 3 2 3 4 7 Toolbar The toolbar offers the buttons New entity Duplicate entity Delete entity and Copy to All of these actions can also be accessed in the context menu of each tree node Right click on a library or geometry tree node to open the context menu The toolbar furthermore contains the buttons Collapse and Filter whereas the context menu has the button Set type All buttons are described below Button New entity This button creates a new entity The type of entity material fraction isotope is deter mined based on the currently selected tree node That means if e g the Elements node is selected the New button will create a new empty element A special characteristic of the new button has to do with the creation of composites or fractions If you create a new composite under a user defined material or a new fraction under an element or material it will automatically change the type of the parent element or material to whatever you added to the parent See description of the button Set type below for details Button Duplicate entity The Duplicate button simply creates a copy of the selected entity and puts it in the same tree geometry or library tree Button Delete entity This button deletes the cur
63. After pressing the Save button the file is written to the disk STEP AP is an ASCII format so the exported file can be viewed and modified by a text editor Internally ESABASE2 uses the OpenCASCADE Step Exporter which maps the displayed To poDS Shapes into the STEP AP format The export can be applied to all kind of geometries ESABASE2 Framework Date 2013 07 23 Software User Manual Revision 1 8 2 Reference R077 230rep_01_08_02_Software_User_Manual_Framework doc State Final etamax space GmbH Frankfurter Str 3D 38122 Braunschweig Page 99 176 3 3 Kinematics Kinematics was briefly discussed in tutorial style in section 3 2 3 5 and 3 2 3 6 This section discusses kinematics in more detail In a spacecraft geometry the system is represented by the central body of the geometric model typically the spacecraft s platform which carries all other bodies solar panels an tennas rotors etc The pointing of the system is directly specified on the System node of the geometric model The system is modelled in three steps Establishment of the geometric objects considering the intended model hierarchy via the geometry wizards pages Size Meshing Position amp Attitude Debris Definition of the system s pointing via the Outline right click on System select Mod ify object from the context menu go to the Pointing page and specify the required pointing directions Definition of
64. E2 Framework Revision 1 8 2 Software User Manual State Final Reference R077 230rep_01_08_02_Software_User_Manual_Framework doc Page 80 176 etamax space GmbH Frankfurter Str 3D 38122 Braunschweig 3 2 4 3 Shape Information Our view of the Outline has been quite shallow yet Expanding the tree nodes and at the same time looking at the Properties view can show you much about the internal data struc tures of a geometry file as shown in the following figure Figure 3 40 Geometry editor Outline expanded The tree on the right is an expanded version of the tree on the left ESABASE2 Framework Date 2013 07 23 Software User Manual Revision 1 8 2 Reference R077 230rep_01_08_02_Software_User_Manual_Framework doc State Final etamax space GmbH Frankfurter Str 3D 38122 Braunschweig Page 81 176 As the panel is a flat box you can see its 6 surfaces and below the last surface its meshed elements 4 elements per surface These are the elements whose coordinates will be used in Debris and other analyses When looking at the Properties view at the same time you can see the data values for each node in the Outline e g the element area and the normal vector for a meshed element as shown on the left in the following figure Figure 3 41 Geometry editor Outline and Properties view Other nodes are accessible in the same way The right side of the figure above shows the SHAPE node in the Ou
65. EC geocentric sun fixed ecliptic system o x within the ecliptic plane towards the true sun position of date o z perpendicular to ecliptic plane towards the ecliptic North pole o y completes the right hand system x y z EARTHE topocentric equatorial system o x parallel to the equatorial plane towards East o z perpendicular to the equatorial plane towards North o y completes the right hand system x y z EARTHG topocentric centred at a point on earth s reference ellipsoid surface hori zontal system o x within the body horizontal plane towards East o y within the body horizontal plane towards North o z geodetic normal completes the right hand system x y z ORBITG geocentric radius related system roll pitch yaw o x within the orbital plane directed from earth centre to the satellite o z perpendicular to the orbit plane in the direction of the angular momentum vector o y completes the right hand system x y z ORBITT geocentric velocity related orbital system o y within the orbital plane along the absolute velocity vector o z perpendicular to the orbit plane in the direction of the angular momentum vector o x completes the right hand system x y z EARTHLEQ selenocentric Earth fixed tilted lunar equator system o x within the orbital plane towards the true Earth position of date o z perpendicular to x in the direction of the north o y within the equatorial plane completes the right hand
66. For ESABASE2 relevant formats are STEP AP 214 and AP 203 BAS File Import Used by the original ESABASE many spacecraft geometries defined in the BAS format can be re used in ESABASE2 GDML File Import GDML is a popular geometry model format in the radiation do main STEP SPE File Import STEP SPE is a protocol for geometry models developed by ESA in the course of several activities It is a combination of STEP TAS and STEP NRF ESABASE2 Framework Date 2013 07 23 Software User Manual Revision 1 8 2 Reference R077 230rep_01_08_02_Software_User_Manual_Framework doc State Final etamax space GmbH Frankfurter Str 3D 38122 Braunschweig Page 87 176 From STEP TAS the geometry definitions are included in STEP SPE and STEP NRF contributes to this new protocol by providing means to define generic data structures 3 2 6 1 STEP File Import As of ESABASE2 version 4 0 0 the STEP AP 214 protocol is supported but not AP 203 STEP SPE yet Also please note that the size and form of imported STEP shapes cannot be changed within the geometry editor the reason is that STEP shapes translate to an element mesh but not necessarily to attributes needed by the shape wizard To import a STEP AP geometry create a new geometry file by using the menubar choose File New Geometry The resulting wizard is shown in the following figure Figure 3 49 Geometry file creation wizard STEP variant On the first page cho
67. Import Users of the original ESABASE can re use their geometry BAS files in ESABASE2 using the BAS import In the menubar choose File New Geometry and consider the wizard shown in the following figure Figure 3 51 Geometry file creation wizard BAS variant As with STEP only the pure geometry is imported excluding kinematics and pointing as this was specified in CMD files Also please note that certain constructs are not supported see section 5 4 1 and that the file name of the BAS file may not exceed 12 3 characters BAS shapes can be edited normally in the Geometry editor they are the same as shapes created with the shape wizard Notable exceptions are facets which are not based on points i e circle line polynom only points are supported by the shape wizard in the geometry editor Meshing however works on all imported shapes Date 2013 07 23 ESABASE2 Framework Revision 1 8 2 Software User Manual State Final Reference R077 230rep_01_08_02_Software_User_Manual_Framework doc Page 90 176 etamax space GmbH Frankfurter Str 3D 38122 Braunschweig The figure below shows a model of the HUBBLE Space Telescope imported via BAS file Figure 3 52 Geometry editor imported HUBBLE BAS A sensible way to convert BAS files is to import them check the existence of all shapes COPY statements will be translated into duplicated objects in the ESABASE2 geometry file and re apply kinematics and
68. MINUM is now being used Date 2013 07 23 ESABASE2 Framework Revision 1 8 2 Software User Manual State Final Reference R077 230rep_01_08_02_Software_User_Manual_Framework doc Page 68 176 etamax space GmbH Frankfurter Str 3D 38122 Braunschweig Figure 3 27 Material overview page select a material for all surfaces ESABASE2 Framework Date 2013 07 23 Software User Manual Revision 1 8 2 Reference R077 230rep_01_08_02_Software_User_Manual_Framework doc State Final etamax space GmbH Frankfurter Str 3D 38122 Braunschweig Page 69 176 3 2 3 5 Antenna dish Global Kinematics and Pointing The following subsections are examples but not full specifications of kinematics and point ing For a full description of both functionalities please see sections 3 3 and 3 4 To extend our example satellite we will add a parabole antenna dish which shall always point to earth We start with the antenna dish instead of the solar panels because it will force the satellite system to rotate and system pointing must always be defined before sec ondary local pointing Select the main body box in the 3D view and open the context menu to choose first Coordi nate Systems global and local coordinate systems You will now see the local coordinate system for each shape this will be useful below Again select the main body box and choose Add Child Parabole from the context menu Set p1 0
69. PE export in the outline 97 Figure 3 62 STEP export in the outline 98 Figure 3 63 Spacecraft model 103 Figure 3 64 Pointing realisation 113 Figure 3 65 Attitude indeterminacy central body 114 Figure 3 66 Attitude indeterminacy 2 degrees of freedom 115 Figure 5 1 Troubleshooting Messages ESABASE2 Debris analysis 121 Figure 5 2 Troubleshooting Messages Eclipse and JVM abnormal termination 122 Figure 5 3 Troubleshooting Messages Solver warning kinematic 123 Figure 5 4 Application of the ESABASE mesher in the Outline 126 Figure 6 1 Basic 3D geometry shapes 128 Figure 6 2 Parameters of a box object in ESABASE left and GDML right style 129 Figure 6 3 Outer shape parameters of a cone object in ESABASE left and GDML right style 132
70. Parameter xSemiAxis defines the radius in centre of the ellipsoid and parameter ySemiAxis defines the half length in y direction of the ellipsoid Parameter zSemiAxis will be changed automatically with xSemiAxis By default the ellipsoid is a solid ellipsoid thick is empty To change this in ESABASE style the thickness of the walls of the ellipsoid thick can be defined When the thickness is set to 0 then the walls are infinitely thin If the thickness is defined then diam is the external diameter of the circle around the point p1 In order to segment the ellipsoid p3 angle1 and angle2 need to be specified The points p1 p2 and p3 define the plane which serves as a starting point for the angles Going from that point angle1 defines the start and angle2 defines the end of the segment around the axis p1 p2 To truncate the ellipsoid h1 or h2 ESABASE or zBottomCut or zTopCut GDML must be defined By defining h1 zBottomCut the bottom half of the ellipsoid can be truncated h1 is the length from p1 to h1 along the vector p1 p2 zBottomCut is the length from the centre to zBottomCut along the y Axis By defining h2 zTopCut the top half of the ellipsoid can be truncated h2 is the length from p1 to h2 along the vector p1 p2 zTopCut is the legth from the centre to zTopCut along the y Axis 6 1 4 3 Meshing The meshing parameters are expressed along meshing directions a b c respectively These directions are shown in
71. Please note that this view is not available when choosing Moon as central body in the Or bit Data tab ESABASE2 Framework Date 2013 07 23 Software User Manual Revision 1 8 2 Reference R077 230rep_01_08_02_Software_User_Manual_Framework doc State Final etamax space GmbH Frankfurter Str 3D 38122 Braunschweig Page 39 176 3 1 6 Import of INP Files Users of the original ESABASE can re use their mission specifications by importing INP files Select File New Mission in the menubar and the wizard shown in the following figure will appear Figure 3 6 Mission file creation wizard for INP files On the first page Create empty file is the default option Change this to Import INP and click Next Then on the second page enter the location of the INP file and press Next again On the last page enter file name and location within the project Upon pressing Finish the file will be created and the mission editor for it will be opened Date 2013 07 23 ESABASE2 Framework Revision 1 8 2 Software User Manual State Final Reference R077 230rep_01_08_02_Software_User_Manual_Framework doc Page 40 176 etamax space GmbH Frankfurter Str 3D 38122 Braunschweig 3 1 7 Trajectory File As an alternative to a mission file it is also possible to use so called trajectory files to define a set of state vectors to define an orbit A trajectory file is an ASCII based text
72. Save Close and Exit entries with its variants The Convert Line Delimiters To allows you to convert text files from Windows to Unix and vice versa With Switch workspace you can specify a non default workspace loca tion though this is not recommended In the Edit menu you find Copy and Delete A Paste operation is not included it will appear only in context menus above the appropriate places e g geometrical shapes or nodes in the Outline The Help menu contains an About box yielding among others the version of ESABASE2 you are using and the integrated Help The Window menu allows you to customize your Perspective which is the current layout of the views you see in the application window You can actually have more than one perspec ESABASE2 Framework Date 2013 07 23 Software User Manual Revision 1 8 2 Reference R077 230rep_01_08_02_Software_User_Manual_Framework doc State Final etamax space GmbH Frankfurter Str 3D 38122 Braunschweig Page 175 176 tive although you will probably not use this With the Show view entry you can control which views will be show e g only explorer and editor area are possible In addition the Window menu gives you access to the Preferences in which you can modify various aspects of running ESABASE2 Finally the Help menu provides an About dialog and a link to the help system the latter is depicted in the figure below Figure 7 2 ESABASE2 hel
73. Str 3D 38122 Braunschweig 6 Annex A Geometry Shapes The original ESABASE framework 6 dictates the shape palette available in ESABASE2 In addition the Torus Tetrahedron and the Trapezoid GDML shapes from the REAT MS editor were integrated within the course of Data Exchange Methods for Space Environment Tools ESA contract number 4000101301 The following sections describe the definition and specific parameters of all available objects structured into the subchapters Basic 3D Shapes Geometrical bodies which could appear in any CAD program Basic 2D Shapes Two dimensional shapes with a front and back side Specific Shapes Flat or extruded shapes based on the Facet concept Complex Shapes Unusual bodies that aid in the construction of spacecraft As of ESABASE2 Release 4 0 Antenna and Ogive shapes are no longer supported They can not be created or imported In addition it is no longer possible to create or import shapes with an ellipsoid base Both changes are due to the fact that the shape palette is now im plemented using so called OCC shapes 6 1 Basic 3D Shapes Basic three dimensional geometrical shapes encompass the following Box Cone Cylinder Ellipsoid Paraboloid Sphere It is completely reasonable to form a first S C approximation from these shapes more de tailed analyses would make use from more specialised shapes The following figure gives a visual index Figure 6 1 Basic
74. _01_08_02_Software_User_Manual_Framework doc State Final etamax space GmbH Frankfurter Str 3D 38122 Braunschweig Page 41 176 Epoch This option must also be specified It defines the epoch format and valid op tions are MJD and UTC For each supplied state vector one line shall be used The section in which the state vectors are defined shall be started with the BEGIN tag and should end with END The format of the state vectors is epoch X Y Z X_dot Y_dot Z_dot Please note that trajectory files can only be used for the Debris application This mechanism does not work for any other application For more details on how to use the trajectory file see 2 Date 2013 07 23 ESABASE2 Framework Revision 1 8 2 Software User Manual State Final Reference R077 230rep_01_08_02_Software_User_Manual_Framework doc Page 42 176 etamax space GmbH Frankfurter Str 3D 38122 Braunschweig 3 1 8 Orbit Propagator This subsection describes details of how orbital points are calculated from the mission speci fication It is particularly interesting to original ESABASE users The subsection is structured as follows Introduction to SAPRE Description of the SAPRE orbit propagator Restrictions of SAPRE Explains limitations of SAPRE Input Parameters for Sapre Describes how SAPRE views the input parameters in the mission editor 3 1 8 1 Introduction to SAPRE Many ESABASE a
75. adable by ESABASE2 version 1 4 2 It is always possible that a file of an older version can be imported and used in a newer version of an application but not vice versa Date 2013 07 23 ESABASE2 Framework Revision 1 8 2 Software User Manual State Final Reference R077 230rep_01_08_02_Software_User_Manual_Framework doc Page 22 176 etamax space GmbH Frankfurter Str 3D 38122 Braunschweig 2 1 5 Starting ESABASE2 To launch the ESABASE2 application double click the file esabase2 exe in the application direc tory A splash screen will appear to accompany the loading process after which the main GUI will become visible on screen as illustrated by the following screenshot Figure 2 3 ESABASE2 user interface You will notice that the GUI consists of multiple sub windows called views In the figure above the left column consists of an ESABASE2 Explorer and an Outline to the right most of the place is taken by a spacecraft geometry editor and at the bottom you can see a Properties view The next section will explain the usage of the GUI ESABASE2 Framework Date 2013 07 23 Software User Manual Revision 1 8 2 Reference R077 230rep_01_08_02_Software_User_Manual_Framework doc State Final etamax space GmbH Frankfurter Str 3D 38122 Braunschweig Page 23 176 2 2 Basic GUI Usage After reading this chapter you will be able to navigate the GUI and make sense of the ESABASE2 work
76. al mm 0 lt thick lt diam 2 solid Wall thickness of the sphere If thick 0 the shape is a surface p2 point mm mm mm Second point of the axis of revolution defined by the vector p1p2 h1 real mm diam 2 h1 lt h2 diam 2 diam 2 Location of the base of the sphere with respect to point p1 along the vector p1p2 for generating a truncated sphere h2 real mm diam 2 h1 lt h2 diam 2 diam 2 Location of the top of the sphere with respect to point p1 along the vector p1p2 for generating a truncated ESABASE2 Framework Date 2013 07 23 Software User Manual Revision 1 8 2 Reference R077 230rep_01_08_02_Software_User_Manual_Framework doc State Final etamax space GmbH Frankfurter Str 3D 38122 Braunschweig Page 147 176 Parameter Type Unit Range Default Description sphere p3 point mm mm mm Optional point defining the plane p1p2p3 The intersec tion of this plane with the sphere acts as the reference for generating a segment and for specifying the direc tion of diame and also for specifying the starting point of the meshing into nodes and elements angle1 real deg 0 lt angle1 lt angle2 lt 360 0 Start angle with reference to the plane p1p2p3 for gener ating a segment angle2 real deg 0 lt angle1 lt angle2 lt 360 360 End angle with reference to the plane p1p2p3 for gener ating a segment Table 6 10 Defin
77. alculated by the orbit generator during the analysis This can happen because the mission editor does not consider perturbations see 3 1 3 which lead to acceleration or deceleration of the spacecraft Changes on the data in the textfields of the Orbit Data tab are directly sent to the visuali sation tabs called Visualization tab 3D view and Ground Track tab 2D view If you enter data outside the specified interval an error popup window is shown Additionally the ESABASE2 Framework Date 2013 07 23 Software User Manual Revision 1 8 2 Reference R077 230rep_01_08_02_Software_User_Manual_Framework doc State Final etamax space GmbH Frankfurter Str 3D 38122 Braunschweig Page 35 176 textfield background containing the wrong data is coloured red The visualisation tabs are not updated with wrong data inputs Date 2013 07 23 ESABASE2 Framework Revision 1 8 2 Software User Manual State Final Reference R077 230rep_01_08_02_Software_User_Manual_Framework doc Page 36 176 etamax space GmbH Frankfurter Str 3D 38122 Braunschweig 3 1 3 Mission Outline and Properties View Expert users of the original ESABASE may edit further properties using Outline and Proper ties view The following figure shows the pertinent points in the GUI Figure 3 3 Mission Editor with Pertubations in Outline Select the Perturbations node in the Outline and click on a value in the Properties vi
78. ample satellite with two solar panels Please note that in the geometry editor neither kinematics nor pointing is visualised in the 3D view Only in the different solvers result editors you can see the different configurations per orbital point As an example the following figure shows the orbital points of an ESABASE2 Debris run using MASTER 2001 on a sun synchronous orbit Figure 3 35 Orbital point configurations example satellite Read on to the next section to learn how to give shapes more intuitive names Date 2013 07 23 ESABASE2 Framework Revision 1 8 2 Software User Manual State Final Reference R077 230rep_01_08_02_Software_User_Manual_Framework doc Page 76 176 etamax space GmbH Frankfurter Str 3D 38122 Braunschweig 3 2 4 Geometry Outline and Properties View In the Outline view you can see the tree structure of the satellite geometry created in the previous subsections This Outline is good for several things Shape Naming Allows you to rename shapes such as BOX to Central body or So lar panel left Copy amp Paste How to duplicate parts of the geometry model Shape Information See the exact contents of each shape down to surface and meshed element level Shape Editing How to edit geometry values in the Property editor with the help of the Outline Enclosures A typical case for editing values in the property editor Enclosures are ad vanced functionality that is not integr
79. angles Going from that point angle1 defines the start and angle2 de fines the end of the segment around the axis p1 p2 To segment the cylinder in GDML style the parameters sPhi and dPhi have to be specified Parameter sPhi defines the start angle and parameter dPhi defines the size of the segment 6 1 3 3 Meshing The meshing parameters are expressed along meshing directions a b c respectively These directions are shown in Figure 6 5 along with how the elements are numbered Figure 6 5 Meshing parameters of the cylinder Date 2013 07 23 ESABASE2 Framework Revision 1 8 2 Software User Manual State Final Reference R077 230rep_01_08_02_Software_User_Manual_Framework doc Page 138 176 etamax space GmbH Frankfurter Str 3D 38122 Braunschweig 6 1 4 Ellipsoid Figure 6 6 Parameters of an ellipsoid object in ESABASE left and GMDL right style 6 1 4 1 Purpose To describe the shape of a complete circular or elliptical ellipsoid or a sector of an ellipsoid Parameter Type Unit Range Default Description p1 point mm mm mm 0 3000 0 Origin of the shape and the first point of the axis of revolution p2 point mm mm mm 0 3000 0 Second point of the axis of revolution defined by the vector p1p2 diam real mm gt 0 5000 External diameter of the circular ellipsoid or the external minor axis of the elliptical ellipsoid per pendicular to the plane
80. ated into the Geometry editor 3 2 4 1 Shape Naming In the last subsection you have defined a spacecraft geometry represented as a 3D model The shapes are ordered hierarchically depending on the shape you performed Add Child upon To see this hierarchy consider the outline on the left side of the following figure Figure 3 36 Geometry editor Outline Cone selected From the GeomModel root node you see the System node where you specified the sys tem pointing in chapter 3 2 3 5 and further below a hierarchy of BOX then CONE PARABOLE CYLINDER and further shapes ESABASE2 Framework Date 2013 07 23 Software User Manual Revision 1 8 2 Reference R077 230rep_01_08_02_Software_User_Manual_Framework doc State Final etamax space GmbH Frankfurter Str 3D 38122 Braunschweig Page 77 176 When you select CONE with a leftclick the cone in the 3D area is highlighted so you know which node belongs to which shape However a name like CONE is not really intuitive to change that rightclick in the node in the Outline and choose Rename The following figure shows the resulting Rename dialog where you can edit e g Front shield as a more appropriate name Figure 3 37 Geometry editor Outline Cone renaming Continue in this manner and rename the BOX to Central body the PARABOLE to Earth antenna the cylinders to Solar panel left and Solar panel right and the cylinders chil
81. aterials tree the library materials tree and the properties view A toolbar is located at the top Figure 3 24 Material Editing Page 3 2 3 4 4 Geometry materials The geometry materials tree lists all elements isotopes and materials in the following we call these three types entities that are stored in the geometry file Initially a geometry file ESABASE2 Framework Date 2013 07 23 Software User Manual Revision 1 8 2 Reference R077 230rep_01_08_02_Software_User_Manual_Framework doc State Final etamax space GmbH Frankfurter Str 3D 38122 Braunschweig Page 65 176 contains none of these entities You can either create new entities or copy them from the library 3 2 3 4 5 Library materials The library materials tree lists all entities that are stored in the ESABASE2 material library The material library contains all elements from the periodic table and a selection of the most common materials Those pre defined standard materials can never be deleted or changed and work as a basis to create new materials via duplication 3 2 3 4 6 Properties view Figure 3 25 shows the properties view populated with the values of the material ALUMINUM 1 which was created by copying the original material ALUMINUM with the Du plicate button Figure 3 25 Material editing page Properties view Date 2013 07 23 ESABASE2 Framework Revision 1 8 2 Software User Manual State Final Reference R0
82. ble 6 21 Definition of the TRUSS4 shape 173 Date 2013 07 23 ESABASE2 Framework Revision 1 8 2 Software User Manual State Final Reference R077 230rep_01_08_02_Software_User_Manual_Framework doc Page 16 176 etamax space GmbH Frankfurter Str 3D 38122 Braunschweig 1 Introduction Before you dive into the ESABASE2 analysis work this short introduction will provide you with a birds eye view understanding with the help of the following items The Big Picture Where does ESABASE2 stand Chapter overview So you find your way through the chapters more quickly Problem Reporting What to do if you encounter troubles 1 1 The Big Picture ESABASE2 is a software application and framework for space environment analyses which play a vital role in spacecraft mission planning Currently 2013 it encompasses De bris meteoroid 2 Atmosphere ionosphere 3 Contamination outgassing 4 and Sunlight 5 analyses with this it complements other aspects of mission planning like thermal or power generator design In CCN 9 the Debris application was extended to allow the analysis of lunar missions The application grew from ESABASE2 Debris an application for space debris and micro meteoroid impact and damage analysis which in turn is based on the original ESABASE Debris software 6 developed by different companies under ESA contract ESABASE2 adds a m
83. box with its corner point ESABASE or its central point GDML at the origin of the local reference frame In ESABASE style the default values describe a solid box An enclosed cavity may be described by defining the thickness of the box If the parameter thickness is disabled default setting the resulting shape is a solid with 6 faces in the following order x y x y z z If the parameter thickness is enabled and bigger than 0 the resulting shape is a volume with 12 faces the outer faces x y x y z z and the inner faces in the same order If the parameter thickness is enabled and equals 0 the shape is a surface with 12 faces in the order outer face x its inner face outer face y its inner face etc x means the face in the yz plane given by the maximum x value x means the face in the yz plane given by the minimum x value etc The wall are infinitely thin By default the complete boundary surface of the shape is active except if the shape has a fully enclosed cavity In this case enclosed cavity is not active and hence not present in sur face node ray tracing analyses e g ESABASE THERMAL If the shape is a surface shape thickness 0 or has a fully enclosed cavity this default can be changed via the respective drop down menu on the Meshing page of the shape wizard A box can be specified by defining the length of the x y and z axis dx dy dz The lower right corner red dot is the point o
84. cake out of it The apex of the paraboloid can be truncated For a basic paraboloid full paraboloid the user needs to specify only two parameters Pa rameter p1 defines the centre point of the top of the paraboloid and p2 define the centre point at base of the paraboloid As a default diam which is the external diameter of the circular paraboloid base will be 4 p1p2 Because no more parameters are defined the paraboloid will be full and complete paraboloid By default the paraboloid is a solid parabol oid thick is empty To change this the thickness of the walls of the paraboloid thick needs to be specified When the thickness is set to 0 the walls are infinitely thin When the thickness is defined diam is the external diameter of the circular base of the paraboloid In order to segment the paraboloid p3 angle1 and angle2 have to be specified The points p3 p1 and p2 define the plane which serves as starting point for the angles Going from that point angle1 defines the start and angle2 defines the end of the segment around the axis p1p2 To truncate the paraboloid the user has to define h1 which is the length from p1 to h1 along the vector p1p2 h2 has to be defined also which is then the location of base of the paraboloid 6 1 5 3 Meshing The meshing directions a b c are shown in the Figure 6 9 along with how the elements are numbered The numbering of nodes and elements of the shape is accord
85. ce By default the complete boundary surface of the shape is active For a surface shape only one side of the boundary surface can be made active by changing this default via the respective drop down menu on the Meshing page of the shape wizard Depending on the shape s parameter values the shape s boundary surface has up to 6 faces outer and Date 2013 07 23 ESABASE2 Framework Revision 1 8 2 Software User Manual State Final Reference R077 230rep_01_08_02_Software_User_Manual_Framework doc Page 134 176 etamax space GmbH Frankfurter Str 3D 38122 Braunschweig inner cone base and top disc cut faces at angle1 and angle2 ESABASE style or sPhi and dPhi GDML style When defining the cone shape the user can choose from several possible options The apex of the cone can be truncated The cone can be segmented vertically i e like cutting a piece of cake out of it For a basic cone full cone in ESABASE style only three parameters need to be specified Parameter p1 defines the centre point of the base of the cone p2 defines the centre point of the apex of the cone and diam1 defines the diameter of the base of the cone Because no more parameters are defined the cone will be a full and complete cone By default the cone is a solid cone thick is empty The thickness of the walls of the cone can be defined thick If the thickness is defined to be 0 then the walls are infinitely thin and diam1 i
86. ces Run time errors of ESABASE2 are displayed in a dedicated window on the screen e g Figure 5 1 The application will be terminated after the occurrence of a run time error Run time errors of the JVM or of the Eclipse platform are displayed in a dedicated window on the screen e g Figure 5 2 The application will be terminated after the occurrence of such run time errors Solver error messages are displayed in a dedicated window on the screen e g Figure 5 3 The behaviour of ESABASE2 depends on the type of error In case of fatal er rors the analysis e g Debris will be terminated and the focus will be on the GUI again 5 3 1 Messages ESABASE2 ESABASE2 analyses are typically executed in Fortran code With exotic data configurations errors may be produced Such errors will be shown as a popup window as shown in the fol lowing figure Figure 5 1 Troubleshooting Messages ESABASE2 Debris analysis It is not possible to continue the analysis after such an error Please check your input files for unusual configurations e g a box with negative dimension in a geometry file and make a screenshot of the error dialog when reporting the issue Date 2013 07 23 ESABASE2 Framework Revision 1 8 2 Software User Manual State Final Reference R077 230rep_01_08_02_Software_User_Manual_Framework doc Page 122 176 etamax space GmbH Frankfurter Str 3D 38122 Braunschweig 5 3 2 Messages Eclipse and JVM
87. ci fied for the central body then it has one rotational degree of freedom left namely rotation about that pointing vector The remaining degree of freedom is used to point the central body in either of two ways A second set of pointing vectors and directions is specified using VEC2 and pdir the pointing facility minimises the angle between the pointing vector and the second specified direction A body is attached to the central body using the Inherit parent values parameter The remaining degree of freedom is then used to minimise the angle between that body s pointing vector and its required pointing direction Please note that the first option is not yet available in ESABASE2 For bodies other than the central body the exact pointing of the pointing vector requires that two rotational degrees of freedom are present Otherwise the pointing will be at best meaning that the angle between the pointing vector and the pointing direction will be mini mised The central body requires two pointing vectors to describe its orientation in space the speci fication of its first pointing vector VEC1 is mandatory while the specification of its second pointing vector VEC2 is optional If the second pointing vector is not specified the orientation of the central body must be further defined by means of the Inherit parent values parameter in the definition of one of the attached bodies the remaining degree of freedom of the cent
88. d The same applies for shapes imported via STEP import In the following the different meshers are explained briefly For a more deeply understanding of the meshers please refer to the appropriate user manuals ESABASE Mesher Along any axis you can modify the number of subdivisions per surface resulting in distinct node areas and further the number of elements per subdivision Multiple axis definitions are combined see figure above Setting a value to 4 on one axis results in slices on a sur face setting 4 on a second axis results in quad division If you just want to fine tune the meshing use the second block Number of elements However if you use a solver that supports surface nodes e g Sunlight 5 you can also use the first block Subdivision into node areas ESABASE2 Framework Date 2013 07 23 Software User Manual Revision 1 8 2 Reference R077 230rep_01_08_02_Software_User_Manual_Framework doc State Final etamax space GmbH Frankfurter Str 3D 38122 Braunschweig Page 57 176 A word on the nomenclature If you take a surface and e g divide it into two na 2 there are now 2 node areas If only one side of the surface is active see below there are 2 sur face nodes if both sides are active there are 4 surface nodes You can think of surface nodes as being the active sides of node areas OCC Mesher The OCC mesher works with a value called deflection Deflection is the maxi
89. d Attitude and Pointing Date 2013 07 23 ESABASE2 Framework Revision 1 8 2 Software User Manual State Final Reference R077 230rep_01_08_02_Software_User_Manual_Framework doc Page 72 176 etamax space GmbH Frankfurter Str 3D 38122 Braunschweig Go to the Pointing page which looks like portrayed by the following figure Figure 3 31 Geometry editor Pointing page System node On this page velocity forward and earth down vectors are set by default Since the parabole takes over the earth pointing deactivate it here by setting VECB 0 0 0 and direction NONE If you were not to do so the parabole and the system pointing would come into conflict Click Finish and the global pointing is adjusted complementing the local pointing per formed on the parabole On a final note please remember that system pointing must always come before secondary local pointing Otherwise the locally pointed shapes will be rotated before the system leading to strange geometries at the orbital points in a solver result file ESABASE2 Framework Date 2013 07 23 Software User Manual Revision 1 8 2 Reference R077 230rep_01_08_02_Software_User_Manual_Framework doc State Final etamax space GmbH Frankfurter Str 3D 38122 Braunschweig Page 73 176 3 2 3 6 Solar panel Local Kinematics amp Pointing In the previous subsection we performed global pointing for the antenna dish Now we
90. d by you in the wizard Date 2013 07 23 ESABASE2 Framework Revision 1 8 2 Software User Manual State Final Reference R077 230rep_01_08_02_Software_User_Manual_Framework doc Page 48 176 etamax space GmbH Frankfurter Str 3D 38122 Braunschweig 3 2 2 Geometry Viewing If the geometry editor is not yet open doubleclick on a geometry file in the ESABASE2 ex plorer This will open the geometry editor as shown in the following figure Figure 3 9 Geometry editor empty file In the left column you see the opened geometry file in the ESABASE2 Explorer the tree structure of the geometry in the Outline with System marked and the selected node s attributes in the Properties view On the right side you see a blank screen as there are no shapes created yet At the top of the editor directly under the cubesat_geometry tab you see a toolbar to manipulate the geometry This subsection s goal is to explain how to view a geometry not how to edit one this is the subject of the following subsection However in order to have something to view press the button indicated by the red circle in the figure above this will provide you with a palette of available shapes ESABASE2 Framework Date 2013 07 23 Software User Manual Revision 1 8 2 Reference R077 230rep_01_08_02_Software_User_Manual_Framework doc State Final etamax space GmbH Frankfurter Str 3D 38122 Braunschweig Page 49 176 S
91. d direction for the particular degree of freedom or by letting the pointing requirements of an attached body fully determine the orientation of the current body Any remaining degrees of freedom will be detected and an error message will be issued With two degrees of freedom exact orientation in a given direction is not always possible if the rotation axes and or one rotation axis and the pointing vector are not perpendicular In two instances this causes the orientation of a body to be indeterminate these indetermi nacies are discussed in the following sections Central Body Indeterminacy When the central body is not fixed Date 2013 07 23 ESABASE2 Framework Revision 1 8 2 Software User Manual State Final Reference R077 230rep_01_08_02_Software_User_Manual_Framework doc Page 114 176 etamax space GmbH Frankfurter Str 3D 38122 Braunschweig Body with two Degrees of Freedom Indeterminacy When an articulated element a joint is not fixed Kinematic Constraints in Pointing How minimum and maximum angle specified as kinematics are applied 3 4 4 1 Central Body Indeterminacy Figure 3 65 represents an earth oriented platform central body and a connected movable body solar array The orientation of the platform is specified by a pointing vector p VEC1 The vector p is fixed in the central body reference frame and in this example it must point towards the earth This condition is satisfied for any pla
92. de Being in this mode allows you to click on a shape which will then be highlighted With this you know how to view a geometry from all sides and we now come to the CAD editing capabilities of the Geometry Editor ESABASE2 Framework Date 2013 07 23 Software User Manual Revision 1 8 2 Reference R077 230rep_01_08_02_Software_User_Manual_Framework doc State Final etamax space GmbH Frankfurter Str 3D 38122 Braunschweig Page 53 176 3 2 3 Geometry Editing Every geometry consists of a tree structure Starting with the System node you define a central body and all other pertinent shapes as children of the central body node or further down the tree structure To create the first and central body shape press the Add object button in the ge ometry editor toolbar and choose the desired shape The following shape types are possible Basic Shapes Geometrical primitives which could appear in any CAD program Box Cone Cylinder Ellipsoid Ogive Paraboloid and Sphere 2D component Shapes Geometries defined partly as a two dimensional blanket Disk Plate Surface and Prism Spacecraft Shapes Unusual shapes that aid in the construction of spacecraft An tenna Beam Pipe Tank and Truss A full description of all shapes can be found in Annex A Geometry Shapes In this section for the purpose of explaining the geometry editor workflow we will compose a simple exam ple satellite as s
93. doc Page 132 176 etamax space GmbH Frankfurter Str 3D 38122 Braunschweig 6 1 2 Cone Figure 6 3 Outer shape parameters of a cone object in ESABASE left and GDML right style 6 1 2 1 Purpose To describe the shape of either a complete or truncated circular or elliptical cone or a sec tion of a cone of a given wall thickness Parameter Type Unit Range Default Description p1 point mm mm mm Centre of the circle at the base of the cone and the first point of the axis of revolution p2 point mm mm mm Centre point of the circle at the apex of the cone and specifies the second point of the axis of revolution defined by the vector p1p2 diam1 real mm gt 0 External diameter of a circle at the base of the cone or external minor diameter of elliptical cone diam2 real mm gt 0 0 complete cone External diameter of the circle at the apex of the cone thick real mm 0 lt thick lt diam1 2 solid cone Thickness of the cone wall per pendicular to the surface If thick 0 the cone is a surface ESABASE2 Framework Date 2013 07 23 Software User Manual Revision 1 8 2 Reference R077 230rep_01_08_02_Software_User_Manual_Framework doc State Final etamax space GmbH Frankfurter Str 3D 38122 Braunschweig Page 133 176 Parameter Type Unit Range Default Description p3 point mm mm mm Optional point defining the plane p1p2p3
94. dren BOX to Panel Besides Rename other operations are available Add child shape is the same as choosing Add child Shape in the 3D view when rightclicking a shape to invoke its context menu Remove is the same as the Remove in the 3D view context menu of a shape Modify object is the same as Modify Size in the 3D view context menu of a shape leading to the first page of the shape wizard Refresh refreshes the Outline structure In rare cases usually involving the import of non standard geometry files this might be come necessary after modifying a shape Copy amp Paste is the subject of the next subsubsection The figure below shows the Outline with renamed shape nodes left and the context menu used to invoke the commands described above right Date 2013 07 23 ESABASE2 Framework Revision 1 8 2 Software User Manual State Final Reference R077 230rep_01_08_02_Software_User_Manual_Framework doc Page 78 176 etamax space GmbH Frankfurter Str 3D 38122 Braunschweig Figure 3 38 Geometry editor Outline node renaming With the shapes now properly named 3D view and Outline together represent a spacecraft geometry more intuitively than the 3D model alone can do ESABASE2 Framework Date 2013 07 23 Software User Manual Revision 1 8 2 Reference R077 230rep_01_08_02_Software_User_Manual_Framework doc State Final etamax space GmbH Frankfurter Str
95. dx dy dz real mm mm mm The translation vector defined by dx dy dz must not be in the same plane as the facet dx dy and dz are translations of the facet in x y and z direc tions in the object reference frame At least one must be specified different from 0 Table 6 15 Definition of the PRISM shape Date 2013 07 23 ESABASE2 Framework Revision 1 8 2 Software User Manual State Final Reference R077 230rep_01_08_02_Software_User_Manual_Framework doc Page 158 176 etamax space GmbH Frankfurter Str 3D 38122 Braunschweig 6 3 2 2 Geometry and Size This shape describes a prism by translating a facet along a vector The resulting shape is always a volume as extruded from the facet The volumn prism has a base top and as many quadrilateral outer faces as the base shape has sides By default the complete boundary surface of the shape is active 6 3 2 3 Meshing The meshing parameters are expressed along meshing directions a and b respectively These directions are shown in Figure 6 17 along with how the elements are numbered ESABASE2 Framework Date 2013 07 23 Software User Manual Revision 1 8 2 Reference R077 230rep_01_08_02_Software_User_Manual_Framework doc State Final etamax space GmbH Frankfurter Str 3D 38122 Braunschweig Page 159 176 6 3 3 Surface Figure 6 18 Parameters of a surface object 6 3 3 1 Purpose To describe the shape of a polygonal sur
96. e 6 10 Definition of the SPHERE shape in ESABASE style 147 Table 6 11 Definition of the SPHERE shape in GDML style 147 Table 6 12 Definition of the DISC shape 152 Table 6 13 Definition of the PLATE shape 153 Table 6 14 Definition of the FACET dummy shape 156 Table 6 15 Definition of the PRISM shape 157 Table 6 16 Definition of the SURFACE shape 159 Table 6 17 Definition of BEAM shape 162 Table 6 18 Definition of the PIPE shape 164 ESABASE2 Framework Date 2013 07 23 Software User Manual Revision 1 8 2 Reference R077 230rep_01_08_02_Software_User_Manual_Framework doc State Final etamax space GmbH Frankfurter Str 3D 38122 Braunschweig Page 15 176 Table 6 19 Definition of the TANK shape 166 Table 6 20 Definition of the TRUSS3 shape 170 Ta
97. e a toolbar for manipulating the viewing perspective scrolling and zooming The buttons are the same as in the geometry editor and will be handled in chapter 3 2 Please note that this view is not available when choosing Moon as central body in the Or bit Data tab Date 2013 07 23 ESABASE2 Framework Revision 1 8 2 Software User Manual State Final Reference R077 230rep_01_08_02_Software_User_Manual_Framework doc Page 38 176 etamax space GmbH Frankfurter Str 3D 38122 Braunschweig 3 1 5 Ground Track The Ground Track view is second possibility to visualize the mission data set in the Orbit Data tab Figure 3 5 Mission Editor Ground track page The Ground Track tab is circled in red In the 2D view you see the orbit as a ground track coloured in green and blue Different colours stand for different revolutions as shown in the legend In the background you can choose between pictures of the earth or shore lines The equator is highlighted in light grey Near the orbit hourly time steps are placed On right mouse click you can open a popup menu to change for example the title or the axis range of the chart Further options are the switch the legend time steps or gridlines on or off On left mouse click you can zoom in the chart To rebuild to initial view there is an option in the popup menu You have also the option to save the chart as an image in the png file format
98. e body is rotated to the closest limit and remains there until a posi tion within the allowed range is required ESABASE2 Framework Date 2013 07 23 Software User Manual Revision 1 8 2 Reference R077 230rep_01_08_02_Software_User_Manual_Framework doc State Final etamax space GmbH Frankfurter Str 3D 38122 Braunschweig Page 101 176 3 3 3 The Central Body The orientation of the central body is conditioned by a first pointing vector which is exactly pointed in the required direction The remaining degree of freedom is used to point the cen tral body in either of two ways A second set of pointing vector and directions is specified and the pointing facility achieves the orientation of the pointing vector which has the minimum angular devia tion from the specified direction A body is attached to the central body using the Inherit parent values parameter The remaining degree of freedom is then used such that the body s pointing vector achieves the orientation which has the minimum angular deviation from the required pointing direction 3 3 4 Articulated Bodies Rotational degrees of freedom are defined on the Kinematic page of the geometry wizards to specify how each body moves with respect to its parent i e defines the direction of the relative angular motion between two linked bodies For pointing purposes each articulated body may have up to two rotational degrees of free dom defined for it The r
99. ee default files 28 Figure 2 11 Creating new files within a project 29 Figure 2 12 Creating folders within a project using the context menu 30 Figure 3 1 Mission file creation wizard 32 Figure 3 2 Mission Editor Outline and Properties view 33 Figure 3 3 Mission Editor with Pertubations in Outline 36 Figure 3 4 Mission Editor Visualisation page 37 Figure 3 5 Mission Editor Ground track page 38 Figure 3 6 Mission file creation wizard for INP files 39 Figure 3 7 Trajectory File 40 Figure 3 8 Geometry file creation wizard 47 Figure 3 9 Geometry editor empty file 48 Figure 3 10 Geometry editor first box 49 Figure 3 11 Geometry button Toolbar
100. ee is no longer crossed This means that a mesh is available for the shape Only unmeshed objects are marked in the outline with a red cross Please note that depending on the complexity of the geometry switching between un meshed and meshed view can take some time Not all shapes are meshed every time the mode is switched Only those shapes which need to be meshed if they had no mesh applied yet if a meshing parameter was changed if the dimension itself was changed are meshed We suggest working in the unmeshed mode to construct the shape and then perform the meshing before using the geometry for an analysis Consider now the toolbar particularly the left part It concerns manipulation of the viewing perspective Please refer to the following figure ESABASE2 Framework Date 2013 07 23 Software User Manual Revision 1 8 2 Reference R077 230rep_01_08_02_Software_User_Manual_Framework doc State Final etamax space GmbH Frankfurter Str 3D 38122 Braunschweig Page 51 176 Figure 3 13 Geometry editor Toolbar left side The first two buttons reset the view the left one tries to fit the geometry to the window showing as much as possible while the right one takes a wider perspective being some dis tance away The next seven buttons allow viewing the model from canonical perspectives front top left view back right bottom view axo all axis 45 view The following four buttons are useful f
101. elease 4 0 this new functionality is supported by the application GDML is a geometry data format popular in the domain of radiation analysis Geant4 To support the interoperability between the different tool frameworks ESABASE2 offers you to export your geometry model into the GDML format This section covers how this export functionality is used For this example we have imported the ATV geometry from a BAS file This BAS file is in cluded in the ESABASE2 distribution The following graphic depicts the spacecraft Figure 3 55 The ATV imported from a BAS file To export this geometry to GDML format two prerequisites have to be met 1 A material shall be assigned to each object to be exported The GDML format requires a defined material for each exported object If no material was assigned a default material will be set in the resulting GDML file to produce a valid GDML file Date 2013 07 23 ESABASE2 Framework Revision 1 8 2 Software User Manual State Final Reference R077 230rep_01_08_02_Software_User_Manual_Framework doc Page 94 176 etamax space GmbH Frankfurter Str 3D 38122 Braunschweig 2 The geometry shall be meshed The GDML format supports only a subset of ESABASE2 shapes If one of the shapes to be exported is not directly supported by GDML the corresponding shape is exported as so called tessellated object This means that the mesh elements are written to GDML instead of a geometry definit
102. elect the Box and in the wizard that opens just press Finish This will produce a box with some sensible default values The following figure shows the newly created box in the 3D view and on the right side a colour scale which matches colours on the surfaces of the cube to object numbers Figure 3 10 Geometry editor first box The box can be viewed in two different modes Unmeshed and meshed The unmeshed view is the default setting when creating a new geometry It displays the shape as 3D object This view is convenient for constructing the spacecraft s geometry as objects can be manipulated and added very fast However to use the geometry with a solver a mesh needs to be ap plied to the geometry Meshing and its parameters are handled in another chapter but to view the mesh one needs to toggle the meshed view by using the button depicted below Figure 3 11 Geometry button Toolbar right side Mesh button If this view is chosen for our box the editor will display the following view Date 2013 07 23 ESABASE2 Framework Revision 1 8 2 Software User Manual State Final Reference R077 230rep_01_08_02_Software_User_Manual_Framework doc Page 50 176 etamax space GmbH Frankfurter Str 3D 38122 Braunschweig Figure 3 12 Geometry Editor in meshed view Now the mesher is applied to the shape and elements are displayed If you look at the out line you will notice that the box element in the object tr
103. ents in the text fields below the first combobox semi major axis km eccentricity 0 1 inclination deg right ascension of the ascending node deg argument of perigee deg true anomaly deg Semi major axis A and eccentricity E can alternatively be defined using apogee altitude and perigee altitude textfields to the right Whenever you leave unfocus one of the lat ter text fields A and E will be re calculated automatically Note that for analysis purposes A and E are always the values that will be evaluated apo gee and perigee altitudes are only helper input methods In the next section Mission Time you specify start and end date of the mission and the number of orbits Please note that some solvers e g Debris will always use number of or bits 1 ignoring deviant input this is hardcoded into the Debris solver and cannot be changed by ESABASE2 The last section Time Interval or Number of Orbital Points is used to specify how many orbital points you want A higher number of orbital points will increase the accuracy of analy sis results but take longer to compute Whenever you make changes in one of the text fields press the Apply button next to it If time interval and number of orbital points are not in sync results may vary depending on the solver you use Please note that the number of orbital points defined in the mission file may differ from the number of actual orbital points c
104. eometry editor Outline Cone selected 76 Figure 3 37 Geometry editor Outline Cone renaming 77 Figure 3 38 Geometry editor Outline node renaming 78 Figure 3 39 Geometry editor Outline Copy amp Paste 79 Figure 3 40 Geometry editor Outline expanded 80 Figure 3 41 Geometry editor Outline and Properties view 81 Figure 3 42 Geometry editor Outline and Properties view editing 82 Figure 3 43 Geometry editor Outline and Properties view Enclosure definition 83 Figure 3 44 Geometry editor Outline and Properties view Enclosure definition 84 Figure 3 45 The context menu in the outline containing the BO 85 Figure 3 46 The shape after performing the operation 85 Date 2013 07 23 ESABASE2 Framework Revision 1 8 2 Software User Manual State Final Reference R077 230rep_01_08_02_Software_User_Manual_Framework doc Page 12 176 etamax space GmbH Frankfurter Str 3D 38122 Braunschweig Figure 3 47 Modifying a BO via the outline
105. eometry file Some useful vectors are calculated in the geocentric inertial equatorial GAMMA 50 reference frame i e sun ephemerides georelay position and inertial direction for the Earth or the bodycentric inertial frame The current pointing directions are determined and are transformed to the GAMMA 50 bodycentric reference frame The transformation matrix between the GAMMA 50 bodycen tric reference frame and the system reference frame is computed by pointing the central body of the geometry in the direction specified by the user All orbit related information is now transformed from the GAMMA 50 bodycentric reference frame to the system reference frame in which the other bodies are pointed so that the orien tation of the pointing vector has the minimum angular deviation from the specified direction in a hierarchical manner the central body is pointed first and then the bodies directly at tached to the central body thereafter the bodies attached to those bodies are pointed and so on Special features such as fixed bodies and no tracking during eclipse are taken into account at this stage ESABASE2 Framework Date 2013 07 23 Software User Manual Revision 1 8 2 Reference R077 230rep_01_08_02_Software_User_Manual_Framework doc State Final etamax space GmbH Frankfurter Str 3D 38122 Braunschweig Page 119 176 4 Solvers Mission and geometry specified above can be used in a number of solvers In order
106. erefore their definition is also non standard They encompass Beam Pipe Tank Truss The following figure gives a visual index Figure 6 19 Complex geometry shapes Date 2013 07 23 ESABASE2 Framework Revision 1 8 2 Software User Manual State Final Reference R077 230rep_01_08_02_Software_User_Manual_Framework doc Page 162 176 etamax space GmbH Frankfurter Str 3D 38122 Braunschweig 6 4 1 Beam Figure 6 20 Parameters of a beam object Figure 6 20 depicts the parameters of the beam object 6 4 1 1 Purpose The beam shape is described by two points p1 and p2 defined as coordinates x y z The beam will be between these two points Additionally the thickness of the beam size can be defined By default the thickness is 50 mm Parameter Type Unit Range Default Description p1 point mm mm mm End point of the beam p2 point mm mm mm End point of the beam size real mm 0 50 Length of the sides of the cross section of the beam Table 6 17 Definition of BEAM shape ESABASE2 Framework Date 2013 07 23 Software User Manual Revision 1 8 2 Reference R077 230rep_01_08_02_Software_User_Manual_Framework doc State Final etamax space GmbH Frankfurter Str 3D 38122 Braunschweig Page 163 176 6 4 1 2 Geometry and Size This shape describes a square section beam between the points p1 and p2 where p1 and p2 are the centre points of
107. es as a starting point for the angles Going from that point angle1 defines the start and angle2 defines the end of the segment around the axis p1p2 To segment the sphere in GDML style sPhi and dPhi have to be specified Parameter sPhi defines the start angle and parameter dPhi defines the size of the segment To truncate the sphere in ESABASE style the user has to define h1 which is the location of the base of the sphere with respect to point p1 and h2 that is the location of the top of the sphere with respect to point p1 To truncate the sphere in GDML style sTheta and dTheta have to be specified sTheta de fines the start angle and dTheta defines size of the segment ESABASE2 Framework Date 2013 07 23 Software User Manual Revision 1 8 2 Reference R077 230rep_01_08_02_Software_User_Manual_Framework doc State Final etamax space GmbH Frankfurter Str 3D 38122 Braunschweig Page 149 176 6 1 6 3 Meshing The meshing directions a b c are shown in Figure 6 11 along with how the elements are numbered Figure 6 11 Meshing parameters of the sphere The numbering of nodes and elements of the shape is according to the face order and num bering directions given in Figure 6 11 outer inner spheres base top cut1 cut2 base top discs inner outer cut 1 cut2 cut1 cut2 faces inner outer base top Note that first value increments fastest For a clearer picture of the node and element num beri
108. est to you Here expert users can manipulate population data and data tables Do so at your own risk and always keep a backup Please do not touch the components configuration plugins and release_dlls folders Only look into the temp directory for curiosity do not change anything there Once you run the application a workspace folder will be added All of your files are saved here Date 2013 07 23 ESABASE2 Framework Revision 1 8 2 Software User Manual State Final Reference R077 230rep_01_08_02_Software_User_Manual_Framework doc Page 20 176 etamax space GmbH Frankfurter Str 3D 38122 Braunschweig 2 1 3 Operating System Adaptations The operating system for ESABASE2 is Windows 2000 SP4 XP SP3 or Vista SP1 With the older OS versions the following components may not be present and must then be installed manually Windows installer version KB884016 v2 x86 DLLs for generic Windows functions version x86_2009_sp2 To install the missing components locate the components install supplements directory below the ESABASE2 base directory as shown in the figure below this is an exception to the don t touch the components directory from the previous subsection Figure 2 2 ESABASE2 directory tree install supplements Doubleclick WindowsInstaller KB884016 v2 x86 exe and follow the instructions Then repeat the same procedure for vcredist_x86_2009_sp2 exe Your system is now equipped with the newe
109. ew to edit it if you cannot see an attribute click Window Preferences in the menubar and set your user mode to expert Wibair air drag parameter Wibspr solar radiation pressure parameter Sun flag to include the gravitational perturbations caused by the sun Moon flag to include the gravitational perturbations caused by the moon Earth flag to include the gravitational perturbations caused by the Earth Kzonal number of zonal harmonics of the earth s gravity field Ktess number of tesseral harmonics of the earth s gravity field Ncira number of the CIRA COSPAR International Reference Atmosphere 1965 atmospheric density model 0 very low solar activity 10 extremely high solar activity ESABASE2 Framework Date 2013 07 23 Software User Manual Revision 1 8 2 Reference R077 230rep_01_08_02_Software_User_Manual_Framework doc State Final etamax space GmbH Frankfurter Str 3D 38122 Braunschweig Page 37 176 3 1 4 Mission Visualisation To visually verify the correctness of the specified orbit you can click the Visualisation tab at the bottom of the mission editor as shown in the following figure Figure 3 4 Mission Editor Visualisation page The Visualisation tab is circled in red In the 3D view you see the orbit as a yellow circle with tiny globes at the approximate spots of the orbital points The equatorial plane is shown in faint white At the top of the editor you se
110. f origin in the local reference frame i e the lower right corner of the box is at 0 0 0 Optionally the user can choose to set the point of origin into the centre of the object By setting the cavity it is possible to get a five sided box with one open side In GDML style a box can be specified by defining the length of the x y and z axis too X Y Z But the Box extends from X to X from Y to Y and from Z to Z Similar to the ESABASE style if the point of origin was set into the centre of the object 6 1 1 3 Meshing The meshing directions a b c are defined in x y and z directions The meshing parameter arguments are the number of elements per node area in the meshing directions a b c re spectively The numbering of nodes and elements of the shape is according to the face order and num bering directions given below first processing the outer faces and then if present the inner faces ESABASE2 Framework Date 2013 07 23 Software User Manual Revision 1 8 2 Reference R077 230rep_01_08_02_Software_User_Manual_Framework doc State Final etamax space GmbH Frankfurter Str 3D 38122 Braunschweig Page 131 176 x face y z y face x z x face y z y face x z z face y x z face y x Date 2013 07 23 ESABASE2 Framework Revision 1 8 2 Software User Manual State Final Reference R077 230rep_01_08_02_Software_User_Manual_Framework
111. face This is the default case 3 2 3 4 2 Material overview section The material overview section shows a list of all materials which are currently stored in the geometry file you are editing It also shows if the material is useful for certain solvers and if the material is currently assigned to a surface column Used This is indicated with either an empty or checked box If you hover over a column title you can see the requirements a material has to fulfil in order for it to be useful for a solver Since we have not added any material to our geometry yet the list is empty Adding materi als to the geometry can be done on the Material Editing page see 3 2 3 4 3 Once a mate rial is copied to or created in the geometry it is available in the material combo boxes in the Assign materials section 3 2 3 4 3 Material editing page We will now use the Material editing page to copy a material from the material library into the geometry file Open the editing page by clicking Edit materials on the Material Over view page Date 2013 07 23 ESABASE2 Framework Revision 1 8 2 Software User Manual State Final Reference R077 230rep_01_08_02_Software_User_Manual_Framework doc Page 64 176 etamax space GmbH Frankfurter Str 3D 38122 Braunschweig Figure 3 23 Material Overview Page Edit materials button The material editing page Figure 3 24 opens It is divided into three sections the geometry m
112. face constructed of up to 64 facets Parameter Type Unit Range Default Description facet lt n gt facet n th facet for the surface Up to 64 facets are supported Table 6 16 Definition of the SURFACE shape 6 3 3 2 Geometry and Size This shape describes a surface constructed of up to 64 facets The surface is constructed by adding the specified facets no checking is performed on the positions of the individual shapes and the boundary lines are not removed The facets do not have to be connected and they do not have to be in the same plane By default the complete boundary surface of the shape is active while the positive sides are the faces with the positive normal Date 2013 07 23 ESABASE2 Framework Revision 1 8 2 Software User Manual State Final Reference R077 230rep_01_08_02_Software_User_Manual_Framework doc Page 160 176 etamax space GmbH Frankfurter Str 3D 38122 Braunschweig 6 3 3 3 Meshing The meshing parameters are expressed along meshing directions a These directions are shown in Figure 6 17 along with how the elements are numbered ESABASE2 Framework Date 2013 07 23 Software User Manual Revision 1 8 2 Reference R077 230rep_01_08_02_Software_User_Manual_Framework doc State Final etamax space GmbH Frankfurter Str 3D 38122 Braunschweig Page 161 176 6 4 Complex Shapes This section details shapes not readily found in standard CAD applications th
113. fault the complete boundary surface of the shape is active except if the shape has a fully enclosed cavity In this case only the positive side is active while the enclosed cavity is not present in surface node ray tracing analyses e g EASBASE THERMAL If the shape is a surface shape thick 0 or has a fully enclosed cavity this default can be changed via the respective drop down menu on the Meshing page of the shape wizard 6 4 3 3 Meshing The meshing directions a and b are shown in Figure 6 23 along with how the elements are numbered Figure 6 23 Meshing parameters of the tank The numbering of nodes and elements of the shape is according to the face order and num bering directions given below Date 2013 07 23 ESABASE2 Framework Revision 1 8 2 Software User Manual State Final Reference R077 230rep_01_08_02_Software_User_Manual_Framework doc Page 168 176 etamax space GmbH Frankfurter Str 3D 38122 Braunschweig outer base cap base top anti clockwise about p1p2 outer cylinder base top anti clockwise about p1p2 outer top cap base top anti clockwise about p1p2 inner base cap base top anti clockwise about p1p2 inner cylinder base top anti clockwise about p1p2 inner top cap base top anti clockwise about p1p2 Note that first value increments fastest For a clearer picture of the node and element num bering please refer to Figure 6 23 ESABASE2 Framework Date 2
114. flow in the following steps GUI Overview Explains the contents of each view within the application and its pur poses GUI Adaptation How to customise the view arrangement to suit your informational needs Project organisation How to create and organise projects and geometry mission and solver files 2 2 1 GUI Overview This subsection will give you an overview of the main GUI parts enumerated from 1 to 6 in the following figure Figure 2 4 User interface overview There is a menu bar 1 a toolbar 2 an editor 3 and then a number of supporting views 4 to 6 Date 2013 07 23 ESABASE2 Framework Revision 1 8 2 Software User Manual State Final Reference R077 230rep_01_08_02_Software_User_Manual_Framework doc Page 24 176 etamax space GmbH Frankfurter Str 3D 38122 Braunschweig They serve the following purposes The menu bar gives full but complex access to all major operations concerning pro jects and files The tool bar gives easy but incomplete access to the most frequently used func tionalities The editor area contains an editor for a file here a geometry editor on a ROSAT spacecraft geometry Each file has its own editor The workspace explorer shows your projects and the folders and the files within it Each file is modelled as a tree structure think directories and files like in your file system The Outline shows the directory nodes Complementary the Pr
115. g Figure 3 17 Geometry editor Box wizard Meshing page Raytracing and sides Date 2013 07 23 ESABASE2 Framework Revision 1 8 2 Software User Manual State Final Reference R077 230rep_01_08_02_Software_User_Manual_Framework doc Page 58 176 etamax space GmbH Frankfurter Str 3D 38122 Braunschweig For volume shapes there are outer positive and inner negative sides for surfacic shapes e g plate one side is usually declared positive the other one negative In the meshing page the following active sides choices are possible positive negative only the outer inner or front back side of a shape is affected both none both or no sides are affected default Depends on the shape For volume shapes the default is positive as the inner side e g of a box is supposed to be never reached by raytracing For surfacic shapes the default is both In addition you can define a ray tracing weighting factor it defaults to 1 0 and sets how many rays are emitted from the surfaces e g setting it to 2 0 means that the surfaces of this shape emit twice as many rays as any other shape in the geometry Please note that solvers may or may not respect the ray tracing weighting factor For each object a transparency can be defined Transparency reaches from 0 to 10 0 means that the object is solid where at level 10 it becomes completely transparent Figure 3 18 Geometry editor transparency set to 5
116. ge Description xSemiAxis real mm gt 0 Length of semi axis in X dimension ySemiAxis real mm gt 0 Length of semi axis in Y dimension zSemiAxis real mm gt 0 Length of semi axis in Z dimension zBottomCut real mm 0 zBottomCut zSemiAxis Z coordinate for a bottom cut The higher the value the more gets cut of zTopCut real mm 0 zTopCut zSemiAxis Z coordinate for a top cut The higher the value the more gets cut of Table 6 8 Definition of the ELLIPSOID shape GDML style Date 2013 07 23 ESABASE2 Framework Revision 1 8 2 Software User Manual State Final Reference R077 230rep_01_08_02_Software_User_Manual_Framework doc Page 140 176 etamax space GmbH Frankfurter Str 3D 38122 Braunschweig 6 1 4 2 Geometry and Size This shape describes a circular ellipsoid or a segment of an ellipsoid from angle1 to an gle2 with a wall thickness determined by thick Depending on the shape s parameter values the shape s boundary surface has up to 6 faces outer and inner ellipsoid base and top disc cut faces at angle1 and angle2 By default the complete boundary surface of the shape is active For a surface shape only one side of the boundary surface can be made active by changing this default via the respec tive drop down menu on the Meshing page of the shape wizard For a basic ellipsoid in GDML style only two parameters need to be specified
117. herit parent values parameter No body may be attached to the current body using the Inherit parent values pa rameter The parent body will be orientated such that the angle between the current body s pointing vector and its required pointing direction is minimised 3 4 2 3 VEC1 This parameter specifies a vector in the body reference frame that will be aligned with the required pointing direction ESABASE2 Framework Date 2013 07 23 Software User Manual Revision 1 8 2 Reference R077 230rep_01_08_02_Software_User_Manual_Framework doc State Final etamax space GmbH Frankfurter Str 3D 38122 Braunschweig Page 107 176 Parameter Type Range Default Description vec vector not parallel with any axis of rotation of the degree s of freedom of the body n a specifies a pointing vec tor Table 3 4 The VEC1 parameter VEC1 may be specified only if VEC1 must be followed by at least one pdir specification VEC1 must be specified if and only if the current body is the central body is not the central body and has 2 rotational degrees of freedom is not the central body has 1 rotational degree of freedom and is attached to its parent body using Inherit parent values VEC1 may not be specified if one other body is attached to the current body using Inherit parent values 3 4 2 4 VEC2 This parameter specifies a vector in the body reference frame that will be aligned w
118. hown in the following figure Figure 3 14 Geometry editor example satellite Date 2013 07 23 ESABASE2 Framework Revision 1 8 2 Software User Manual State Final Reference R077 230rep_01_08_02_Software_User_Manual_Framework doc Page 54 176 etamax space GmbH Frankfurter Str 3D 38122 Braunschweig The satellite above is a fictional Cubesat derivative consisting of a box as central body a cone as front shield a parabole as earth facing antenna two cylinders as solar panel joints two flat boxes as solar panels Re visit the Add Object button and choose Box A wizard to define the shape will open Each shape has its own wizard page other pages are shared among the shapes Alternatively if you already created the box in the previous chapter select the box in the 3D view left click while being in selection mode and then open the context menu right click choosing Modify Size The following wizard pages are available Size This page defines both shape size and point of origin and is unique for each shape Meshing Every shape is divided into surfaces flat or curved which in turn are meshed into elements always flat triangle or quad This page determines meshing detail and active sides Position and Attitude Allows translating and rotating the shape in its own local coor dinate system Kinematic Defines joints that allow child elements to move See subsecti
119. iam1 0 disc Internal diameter of a circular disc or the internal minor axis of an elliptical disc perpendicu lar to plane p1p2p3 for de scribing an annulus Date 2013 07 23 ESABASE2 Framework Revision 1 8 2 Software User Manual State Final Reference R077 230rep_01_08_02_Software_User_Manual_Framework doc Page 152 176 etamax space GmbH Frankfurter Str 3D 38122 Braunschweig Parameter Type Unit Range Default Description p3 point mm mm mm Point defining the plane p1p2p3 The intersection of this plane with the disc acts as the reference for generating a sector and for specifying the direction of diame and also for specifying the starting point of the meshing into nodes and elements angle1 real deg 0 lt angle1 lt angle2 lt 360 0 Start angle with reference to the plane p1p2p3 for generat ing a sector angle2 real deg 0 lt angle1 lt angle2 lt 360 360 End angle with reference to the plane p1p2p3 for generat ing a segment Table 6 12 Definition of the DISC shape 6 2 1 2 Geometry and Size This shape describes a circular or elliptical disc or annulus or a sector of a disc or annulus The DISC is classed as a surface shape By defining diam2 an annulus can be described A sector of a disc or annulus is described by start angle angle1 and end angle angle2 with reference to the plane p1p2p3 The shape has two faces top on side of p2 and base
120. if an gle1 angle2 or diame is specified angle1 real deg 0 lt angle1 lt an gle2 lt 360 0 Start angle with reference to the plane p1p2p3 for generating a segment angle2 real deg 0 lt angle1 lt an gle2 lt 360 360 End angle with reference to the plane p1p2p3 for generating a segment Table 6 9 Definition of the PARABOLOID shape 6 1 5 2 Geometry and Size This shape describes a circular paraboloid or a segment of a paraboloid from angle1 to angle2 with a wall thickness determined by the value of thick The PARABOLOID shape is classed as a surface if thick 0 or a volume otherwise Date 2013 07 23 ESABASE2 Framework Revision 1 8 2 Software User Manual State Final Reference R077 230rep_01_08_02_Software_User_Manual_Framework doc Page 144 176 etamax space GmbH Frankfurter Str 3D 38122 Braunschweig Depending on the shape s parameter values the shape s boundary surface has up to 6 faces outer and inner paraboloid base and top disc cut faces at angle1 and angle2 By default the complete boundary surface of the shape is active For a surface shape only one side of the boundary surface can be made active by changing this default via the respec tive drop down menu on the Meshing page of the shape wizard When defining the paraboloid shape you can choose from several possible options The paraboloid can be segmented vertically i e like cutting a piece of
121. in section 3 2 7 1 We use the simple satellite with two solar panels to demonstrate the export Figure 3 60 A simple satellite structure to demonstrate the STEP SPE export After opening the related geometry file go to the outline and select the System node Please note that the STEP SPE export is only possible on system level and not for single shapes ESABASE2 Framework Date 2013 07 23 Software User Manual Revision 1 8 2 Reference R077 230rep_01_08_02_Software_User_Manual_Framework doc State Final etamax space GmbH Frankfurter Str 3D 38122 Braunschweig Page 97 176 Figure 3 61 STEP SPE export in the outline After selecting the entry a new window opens where you can enter the name and the loca tion of the file which will be created to contain the geometry description in the STEP SPE protocol After pressing the Save button the file is written to the disk STEP SPE is an ASCII format so the exported file can be viewed and modified by a text editor In STEP SPE the shape definitions from STEP TAS are used and if possible ESABASE2 will map the shapes types from the geometry to the STEP TAS types In case this cannot be done ESABASE2 will try to export the shape in question as a tessellated or meshed shape Therefore it will check whether the geometry was already meshed before e g an analysis was performed with it and if it finds an existing mesh it will be exported In case the ge
122. ing to the face order and num bering directions given below outer inner paraboloids top base cutl cut2 base top discs inner outer cut1 cut2 cut1 cut2 faces inner outer base top Note that the first value increments fastest For a clearer picture of the node and element numbering please refer to Figure 6 9 ESABASE2 Framework Date 2013 07 23 Software User Manual Revision 1 8 2 Reference R077 230rep_01_08_02_Software_User_Manual_Framework doc State Final etamax space GmbH Frankfurter Str 3D 38122 Braunschweig Page 145 176 Figure 6 9 Meshing parameters and element numbering of the paraboloid Date 2013 07 23 ESABASE2 Framework Revision 1 8 2 Software User Manual State Final Reference R077 230rep_01_08_02_Software_User_Manual_Framework doc Page 146 176 etamax space GmbH Frankfurter Str 3D 38122 Braunschweig 6 1 6 Sphere Figure 6 10 Parameters of a sphere object in ESABASE left and GDML right style 6 1 6 1 Purpose To describe the shape of a circular or elliptical sphere or a sector of a sphere Parameter Type Unit Range Default Description p1 point mm mm mm Centre of the sphere and the first point of the axis of revo lution diam real mm gt 0 External diameter of the cir cular sphere or the external minor diameter of the ellipti cal sphere perpendicular to the plane p1p2p3 and through the point p1 thick re
123. inimised On the Pointing page of the geometry wizard the degrees of freedom the pointing vectors and the pointing directions are specified If no own kinematic and pointing is specified for a ESABASE2 Framework Date 2013 07 23 Software User Manual Revision 1 8 2 Reference R077 230rep_01_08_02_Software_User_Manual_Framework doc State Final etamax space GmbH Frankfurter Str 3D 38122 Braunschweig Page 105 176 sub object of an articulated object it is assumed to be rigidly connected to its parent object and will be pointed together with the parent object First of all the pointing behaviour of the central body which represents the overall system has to be specified All other bodies specified are connected to the central body either di rectly or through a chain of other bodies The body reference frame of the central body is the system reference frame The origin of this frame is positioned at the orbital points The object reference frames of all other objects are fixed with respect to the respective object and can be translated and rotated with re spect to the system reference frame as specified in the Position amp Attitude parameters of that body Each body is attached to another body through a hinge with 0 1 or 2 rotational degrees of freedom The origin of the joint is the origin of the body reference frame The central body has three rotational degrees of freedom When one pointing vector is spe
124. ion ESABASE2 Framework Date 2013 07 23 Software User Manual Revision 1 8 2 Reference R077 230rep_01_08_02_Software_User_Manual_Framework doc State Final etamax space GmbH Frankfurter Str 3D 38122 Braunschweig Page 63 176 Figure 3 22 Geometry editor Material page It is divided into two sections The upper section named Assign materials and below that the section called Material overview At the bottom is a button called Edit materials which opens the Material Editing Page 3 2 3 4 1 Assign materials section The upper section allows you to apply materials to surfaces in three ways You can assign all materials of the current shape the same material by selecting the option Whole Shape Or you assign each surface its material individually by using the option Individual surface Finally you can replace a material which is already assigned to one or more surfaces with another material The Propagate checkboxes available for the Whole Shape and the Replace option allow the fast modification of the current shapes and all its child shapes By activating the repli cate checkbox of the Whole Shape option not only will all surfaces of the current shape get a new material but also all surfaces of all shapes that are children of the current shape For the Replace option it works analogous Notice that currently no material is assigned to any sur
125. ion This approach of course requires a present mesh If you try to export geometry objects that are not GDML compatible and not meshed manually OCC mesher is performed meshing before exporting to GDML file The sec tion 5 4 3 describes which meshers are suitable for which shapes and why GDML ex porter uses the OCC mesher as default mesher If the geometry is configured correctly the export can be started The export can be per formed either for the whole system or for single objects including their child objects To start an export select the respective object in the outline In this example the whole ge ometry shall be exported so the system node is selected and the context menu is opened Figure 3 56 The GDML export entry in the context menu Use the entry GDML Export A file chooser opens and asks for the directory into which the geometry shall be exported Figure 3 57 The directory for the export is selected Please note that the exporter will create a subdirectory within the selected directory The name of this directory is a combination of the file name and the object id So for our exam ple a new directory is created within GDML_Exports with the name ATV_OBJECT_0 Within this directory a file named mainFile gdml can be found containing the structure description of the GDML data Next to the main file other data files are created on which the main file relies Figure 3 58 ESABASE2 Framewo
126. irection are given in two refer ence frames o the inertial GAMMA 50 reference frame o the system reference frame i e the reference frame of the central body relative orientation and pointing direction of the bodies ESABASE2 Framework Date 2013 07 23 Software User Manual Revision 1 8 2 Reference R077 230rep_01_08_02_Software_User_Manual_Framework doc State Final etamax space GmbH Frankfurter Str 3D 38122 Braunschweig Page 117 176 3 4 6 Pointing Calculation Method The pointing calculation method used can be summarised as follows Transform all system related information body reference frames and pointing vec tors to the reference frame of the central body which represents the reference frame of the articulated system Transform all orbit related information state vector sun ephemerides georelay posi tions and pointing directions to the inertial equatorial GAMMA 50 reference frame Convert all time related information epoch and pointing vectors into modified Julian days Establish the connection between the space environment expressed in the GAMMA 50 reference frame and the system environment expressed in the reference frame of the central body this is performed by pointing the central body Transform the pointing directions to the reference frame of the central body Transform the pointed articulated system and orbit related information to the user specified reference frame for
127. ith the required pointing direction and with VEC1 Parameter Type Range Default Description vecb vector not parallel with any axis of rotation of the degree s of freedom of the body specifies the additional pointing vector of the central body Table 3 5 The VEC2 parameter The following restrictions apply VEC2 may only be used for the central body the System Bodies may no longer be attached to the central body using Inherit parent values VEC2 may be specified only if VEC2 is followed by the corresponding pdir specification VEC1 is specified Date 2013 07 23 ESABASE2 Framework Revision 1 8 2 Software User Manual State Final Reference R077 230rep_01_08_02_Software_User_Manual_Framework doc Page 108 176 etamax space GmbH Frankfurter Str 3D 38122 Braunschweig 3 4 2 5 Direction This parameter must be specified if a VEC1 a VEC2 parameter is specified It defines a pointing direction in a specified reference frame Parameter Type Range Default Description dir vector earth sun velocity georelay fixed cen tral body n a is a parameter specifying a pointing direction Table 3 6 The pdir parameter Six types of pointing direction specifications are made available For a description of the ref erence frames available in ESABASE2 refer to 3 4 3 2 EARTH The body is pointing towards the centre of the earth This is equivalent to di rec
128. ition of the SPHERE shape in ESABASE style Parameter Type Unit Range Description rMin real mm 0 rMin rMax Inner radius of the sphere when set to 0 the sphere is solid rMax real mm gt 0 Outer radius of the sphere sPhi real deg 0 sPhi 360 Starting angle of the segment in radians in the x y plane dPhi real deg 0 dPhi 360 sPhi Size angle of the segment in radians in the x y plane sTheta real deg 0 sTheta 180 Starting angle of the segment in radians in z dimension dTheta real deg 0 dTheta 180 sTheta Size angle of the segment in radians in z dimension Table 6 11 Definition of the SPHERE shape in GDML style 6 1 6 2 Geometry and Size This shape describes a circular sphere or the segment of a sphere defined by angle1 and angle2 ESABASE or sPhi and dPhi with a wall thickness determined by the value of thick Defining parameters h1 and h2 ESABASE or sTheta and dTheta GDML allows the sphere to be truncated The sphere shape is a surface if thick 0 or a volume otherwise Depending on the shape s parameter values the shape s boundary surface has up to 6 faces outer and inner sphere base and top disc cut faces at angle1 and angle2 Date 2013 07 23 ESABASE2 Framework Revision 1 8 2 Software User Manual State Final Reference R077 230rep_01_08_02_Software_User_Manual_Framework doc Page 148 176 etamax space
129. l rotation angle Then a minimum and maximum angle is specified Up to 3 kinematic axes can be defined although in our example we will use only one ESABASE2 Framework Date 2013 07 23 Software User Manual Revision 1 8 2 Reference R077 230rep_01_08_02_Software_User_Manual_Framework doc State Final etamax space GmbH Frankfurter Str 3D 38122 Braunschweig Page 71 176 The Kinematic page of the parabole wizard is shown in the following figure Figure 3 30 Geometry editor Kinematic page antenna dish We ignore the top section translational kinematics see section 3 3 for more and go to the bottom section rotational kinematics which has three 2 line specifications The first line for the axis vector the second line for the 0 vector and to the right the maximum and mini mum angle rmax rmin Since having a pointing requires us to have at least minimal kinematics set the first line to 0 1 0 the second line to 0 0 1 and rmax 0 1 and rmin 0 Then press Finish The pointing and kinematics on the parabole are now configured to allow forcing the parent body to move However the parent body has to accept this Therefore we will edit the global system pointing Go to the Outline You will see a node System here rightclick it and choose Modify Ob ject A wizard will appear and unlike the standard geometry wizard the System node wiz ard shows only pages for Size Position an
130. llowing chapters Chapter 1 Introduction You are reading it right now Chapter 2 Getting Started How to install start and use the software without going into particular solvers debris atmosphere ionosphere Chapter 3 Mission and Spacecraft Definition How to specify the basics mission pa rameters and spacecraft geometry Can be re used with all solvers Chapter 4 Solvers Pointers to the solver handbooks e g Debris or Sunlight Chapter 5 Troubleshooting What to do in case of errors Each solver e g Debris 2 Atmosphere Ionosphere 3 Sunlight 5 has its own hand book this manual explains only the functionality common to all This user manual refers to ESABASE2 version 4 0 0 Other versions of ESABASE2 and of course the original Unix implementation of ESABASE are not covered 1 3 Problem Reporting ESABASE2 has been extensively tested However errors might occur at different layers of the software GUI business layer data handling Aside from the GUI messages the log files in the ESABASE2 logs directory may yield further information If a problem cannot be solved you should contact the ESABASE2 team at etamax space to investigate the issue in detail Please do not hesitate to visit http www esabase2 net for contact information You will also find a problem reporting form in the User s area of the ESABASE2 website Date 2013 07 23 ESABASE2 Framework Revision 1 8 2 Software User Man
131. mum distance between an edge of your mesh and the corresponding surface It is measured in mm The deflection value can be calculated automatically If this option is chosen the deflection will depend on the boundary box around a shape or surface The mesher can work in two ways Either it can mesh the whole shape or each surface can be meshed individually The latter option tends to produce more elements than the first As a rule of thumb one can say that the smaller the deflection value is the finer the mesh becomes In some cases the OCC mesher will orientate the mesh into the opposite direction which e g means that the normals of the mesh elements point inwards the solid This will confuse the solvers To avoid this you may verify the orientation of the relevant elements by ena bling the check box Display Element Normals If the normals point into the wrong direc tion enable or disable the check box Invert Element Normals NetGen Mesher For the NetGen mesher you can choose between two basic modes One based on maximum numbers of elements and one based on edge length specifications change the top check box to activate the appropriate fields For a full discussion of the available parameters refer to the Netgen user manual 9 Further down the meshing page and shown in the figure below the Active Side setting determines which sides of the shape s surfaces are affected by the solvers mostly via ray tracin
132. n file recognisable via the planet plus orbit icon A mission editor will be opened and the Outline and Properties view will be updated The following figure shows the application with an opened mission editor Figure 3 2 Mission Editor Outline and Properties view The mission file is circled in red Below you see the Orbit node selected in the Outline and further below the A semi major axis and other attributes in the Properties view On the right side the mission editor itself is shown The mission editor contains all necessary parameters to specify an orbit and the number of orbital points to be used during an analysis It has three sections Orbit Mission Time Time Interval or Number of Orbital Points Date 2013 07 23 ESABASE2 Framework Revision 1 8 2 Software User Manual State Final Reference R077 230rep_01_08_02_Software_User_Manual_Framework doc Page 34 176 etamax space GmbH Frankfurter Str 3D 38122 Braunschweig Starting with the Orbit section you can choose whether the central body for the mission should be Earth or Moon Please note that Moon is only an option for Debris analysis When choosing Earth you can choose between a predefined geostationary GEO a pre defined sun synchronous SUN or a custom GEN orbit in the first combobox of the editor In most cases you will probably want a custom orbit for that specify the Keplerian ele m
133. n only be used in conjunction with Surface to build a surface type shape or Prism to extrude to a 3D shape 6 3 1 1 Purpose To describe the shape of a planar surface between a series of 3 to 64 points Parameter Type Unit Range Default Description p1 point mm mm mm First point of the facet must lie in a plane with all other points pn point mm mm mm n th point of the facet must lie in a plane with all other points Table 6 14 Definition of the FACET dummy shape 6 3 1 2 Geometry and Size To describe the shape of a planar surface between a series of 3 to 64 points The surface is constructed using the points in the order that they are specified The first and last point are implicitely joind to form the closed facet Facet is a dummy shape and should therefore be labelled so that it can be referred to in the enclosing shape Surface or Prism 6 3 1 3 Meshing As a dummy shape Facet has no meshing ESABASE2 Framework Date 2013 07 23 Software User Manual Revision 1 8 2 Reference R077 230rep_01_08_02_Software_User_Manual_Framework doc State Final etamax space GmbH Frankfurter Str 3D 38122 Braunschweig Page 157 176 6 3 2 Prism Figure 6 17 Parameters of a prism object 6 3 2 1 Purpose To create a prismatic shape from a facet i e to extrude it Parameter Type Unit Range Default Description base facet A previously defined facet
134. nces 1 ESABASE2 homepage http www esabase2 net 2 K Ruhl K D Bunte ESABASE2 Debris software user manual R077 232rep ESA ESTEC Contract 16852 02 NL JA PC Version of DEBRIS Impact Analysis Tool etamax space 2009 3 K Ruhl A Gaede ESABASE2 Atmosphere Ionosphere software user manual R077 233rep ESA ESTEC Contract 21739 08 NL JK Rapid Prototyping Toolkit for Space Environment Engineering Tools etamax space 2009 4 K Ruhl J Weiland ESABASE2 COMOVA software user manual R077 234rep ESA ESTEC Contract 21739 08 NL JK Rapid Prototyping Toolkit for Space Environ ment Engineering Tools etamax space 2009 5 K Ruhl A Gaede ESABASE2 Sunlight software user manual R077 235rep ESA ESTEC Contract 21739 08 NL JK Rapid Prototyping Toolkit for Space Environ ment Engineering Tools etamax space 2009 6 ESABASE User Manual ESABASE GEN UM 070 Issue 1 Mathematics amp Software Di vision ESTEC March 1994 7 SWENET ESA s Space Weather European Network since 2004 http www esa spaceweather net swenet 8 STEP file format http en wikipedia org wiki ISO_10303 9 Netgen mesher user manual http www mathcces rwth aachen de netgen doku php docu ngusermanual 10 P Hake M Zaake Data Exchange Methods for Space Environment Effect Tools de sign definition file R089_221rep ESA ESTEC contract 4000101301 Data Exchange Methods for Space Environment Effect Tools etamax space 2010
135. nd Space Administration OCAF Open CASCADE Application Framework contains the ESABASE2 data model RTP Randomly Tumbling Plate Date 2013 07 23 ESABASE2 Framework Revision 1 8 2 Software User Manual State Final Reference R077 230rep_01_08_02_Software_User_Manual_Framework doc Page 10 176 etamax space GmbH Frankfurter Str 3D 38122 Braunschweig VII List of Figures Figure 2 1 ESABASE2 directory tree 19 Figure 2 2 ESABASE2 directory tree install supplements 20 Figure 2 3 ESABASE2 user interface 22 Figure 2 4 User interface overview 23 Figure 2 5 Menubar and Toolbar 24 Figure 2 6 Explorer Outline Properties view 25 Figure 2 7 Common View buttons 26 Figure 2 8 New Project wizard page 1 27 Figure 2 9 New Project wizard page 2 28 Figure 2 10 A new project and its thr
136. ng please refer to Figure 6 11 Date 2013 07 23 ESABASE2 Framework Revision 1 8 2 Software User Manual State Final Reference R077 230rep_01_08_02_Software_User_Manual_Framework doc Page 150 176 etamax space GmbH Frankfurter Str 3D 38122 Braunschweig 6 2 Basic 2D Shapes Apart from 3D shapes with an inside and an outside you can also define 2D shapes with a front and back side both of which are visible The following shapes are two dimensional Disk Plate The figure below gives a visual index Figure 6 12 Basic 2D geometry shapes ESABASE2 Framework Date 2013 07 23 Software User Manual Revision 1 8 2 Reference R077 230rep_01_08_02_Software_User_Manual_Framework doc State Final etamax space GmbH Frankfurter Str 3D 38122 Braunschweig Page 151 176 6 2 1 Disc Figure 6 13 Parameters of a disc object 6 2 1 1 Purpose To describe the shape of a circular or elliptical disc or annulus or a sector of a disc or annu lus Parameter Type Unit Range Default Description p1 point mm mm mm Centre of the disc and the first point of the axis of revolution p2 point mm mm mm Point of the axis of revolution defined by the vector p1p2 diam1 real mm diam1 gt diam2 gt 0 External diameter of a circular disc or the external minor axis of an elliptical disc perpen dicular to the vector p1p2 diam2 real mm 0 lt diam2 lt d
137. not yet available in ESABASE2 The tracking of a body can be stopped during eclipse of the pointing direction by the earth ESABASE2 Framework Date 2013 07 23 Software User Manual Revision 1 8 2 Reference R077 230rep_01_08_02_Software_User_Manual_Framework doc State Final etamax space GmbH Frankfurter Str 3D 38122 Braunschweig Page 113 176 3 4 4 Pointing the Bodies and Indeterminacies The pointing of the bodies in an articulated system is performed in a hierarchical manner starting from the central body and working outwards from each parent to its children to their children and so on The bodies are pointed so that the orientation of their pointing vec tors has the minimum angular deviation from the specified direction but the specified point ing cannot always be achieved Figure 3 64 illustrates this point if the attitude of the central body is fixed and if the hinge allows only one degree of freedom the connected body the solar panel cannot be exactly orientated towards the sun The pointing is realised by minimising the angle between the fixed body vector the vector normal to the panel and the pointing direction the sun Figure 3 64 Pointing realisation In orbit the positions and orientations of all bodies of the articulated system must be known for a given orbital position Hence all degrees of freedom must be removed This is achieved either by specifying a corresponding pointing vector an
138. ns requiring orbital information SAPRE also generates an ASCII report file which can be displayed on the result file Listings page but is also available in the List ingFiles directory of the active ESABASE2 project It should be noted that SAPRE is intended for the generation of positions over a fairly small number of orbits for use in ESABASE analyses It is not suitable for analysing the long term behaviour of the orbit itself The restrictions on the program are discussed in greater detail in section 3 1 8 2 below ESABASE2 Framework Date 2013 07 23 Software User Manual Revision 1 8 2 Reference R077 230rep_01_08_02_Software_User_Manual_Framework doc State Final etamax space GmbH Frankfurter Str 3D 38122 Braunschweig Page 43 176 3 1 8 2 Restrictions of SAPRE There are a number of restrictions which should be kept in mind when using the orbit gen erator SAPRE does not correctly handle orbital inclinations approaching zero For this reason a minimum inclination of 1E 3 degrees is enforced on input If the inclination falls below this value at any stage the program may fail Thus an orbit exactly in the equatorial plane can not be modelled This is most likely to affect a geostationary orbit where the above restric tion requires the orbit to oscillate at least 700 m from the equatorial plane The user may include the effects of harmonics of the earth s gravitational potential by speci fying how many zonal
139. o cation by ESABASE2 in particular when working with large geometry models ESABASE2 should be closed and restarted from time to time in order to avoid significant per formance losses or even system crashes 5 4 3 Meshing ESABASE2 provides three meshers Netgen OCC and ESABASE cp section 3 2 3 2 It is observed that all three meshes are not able to mesh all available shape types correctly Some meshers do not work properly for some shapes and some shapes are not supported by certain meshers In the current implementation the GDML exporter meshes the shape and exports it as a so called tessellated shape if the shape type is unknown and the shape is meshed by the user In case the shape type is unknown i e in all cases where the geometry was im ported via the STEP importer and the user has not meshed it manually the GDML exporter meshes the shape with the OCC mesher However in most cases the OCC mesher cannot produce correct element normal vectors Nevertheless the OCC mesher is used by default because other meshers are not suitable for complex geometries The import of geometries which are generated with ESABASE2 version 3 leads normally to unmeshed geometries with OCC as default mesher for the objects Date 2013 07 23 ESABASE2 Framework Revision 1 8 2 Software User Manual State Final Reference R077 230rep_01_08_02_Software_User_Manual_Framework doc Page 126 176 etamax space GmbH Frankfurter St
140. odern graphical user interface enabling the user to interactively estab lish and manipulate three dimensional spacecraft models and to display the selected orbit Analysis results can be displayed by means of the colour coded surfaces of the 3D space craft model and by means of various diagrams The development of ESABASE2 was undertaken by etamax space GmbH under the European Space Agency contract No 16852 02 NL JA The first goal was to port ESABASE Debris and its framework user interface to the PC platform Microsoft Windows and to create a modern user interface From the start the software architecture has been expressively designed to accommodate further applications the solvers outlined in the first paragraph were added and more mod ules like e g Radiation are to follow ESABASE2 is written in Fortran 77 ANSI C and Java 6 The GUI is built on top of the Eclipse rich client platform with 3D visualisation and STEP import realised by Open CASCADE Report and graphs are based on the JFreeReport JFreeChart libraries ESABASE2 Framework Date 2013 07 23 Software User Manual Revision 1 8 2 Reference R077 230rep_01_08_02_Software_User_Manual_Framework doc State Final etamax space GmbH Frankfurter Str 3D 38122 Braunschweig Page 17 176 1 2 Chapter Overview This software user manual is intended to be read by persons running the program and in terpreting or using the results of ESABASE2 It contains the fo
141. ointing relation to the parent body VEC1 and VEC2 The pointing vectors Direction The pointing direction Track When pointing is impossible due to eclipse whether to follow or keep still Inverse When several pointing solutions are possible which one to choose All parameters described below are specified via the Kinematic and Pointing pages of the shape wizards in the geometry editor The shape wizards can be called either by right clicking on the System or Object nodes in the geometry editor outline or by selecting the respective object not possible for System in the 3D geometry editor window and opening the context menu by rightclicking 3 4 2 1 General Aspects Up to fifty bodies may be pointed in ESABASE2 The first oriented body is the central body called System which represents the overall system configuration One body or a subtree of bodies can be defined starting at any object of the system The chaining of these bodies is according to their hierarchical interrelation The Geometry Editor offers the user a shortcut to the system pointing It can be found in the toolbar on the right side The pointing facility orientates each body of an articulated system in its required pointing direction starting with the central body If it is not possible to point the body exactly for example if it has only one degree of freedom then the angle between the pointing vector and the pointing direction is m
142. olders To do so rightclick on the project this will open a context menu as shown in the following figure and create a new folder Figure 2 12 Creating folders within a project using the context menu A wizard opens asking you for a directory name in the example above the name mis sion_and_spacecraft is chosen Enter a file name and click Finish To create subfolders repeat the process on the desired parent folder within the ESABASE2 Explorer instead of on the project To move a file to a different folder close any editor operating on the file and then grab hold left mouse button the file move the mouse cursor to the desired folder and drop release left mouse button the file To move a file to the project root directory drop the file on the project name Drag and drop also works between the ESABASE2 Explorer and the Windows Explorer e g to copy files sent to you by email into the ESABASE2 project The specifics of mission and geometry files will be explained in the next section 3 Debris and other solver files will be explained in the solver handbooks ESABASE2 Framework Date 2013 07 23 Software User Manual Revision 1 8 2 Reference R077 230rep_01_08_02_Software_User_Manual_Framework doc State Final etamax space GmbH Frankfurter Str 3D 38122 Braunschweig Page 31 176 3 Mission and Spacecraft Definition Every analysis within ESABASE2 needs a mission specification and a spacecraf
143. ometry Viewing How to navigate around the geometry editor Geometry Editing How to add and modify geometrical elements Geometry Outline and Properties View Describes the tree structure of the geometri cal model as an alternative view on the data Boolean Operations How to perform Boolean Operations STEP and BAS File Import How to import files from other CAD programs and from the original ESABASE GDML Export How to export geometry structures into GDML format We start with the geometry file creation ESABASE2 Framework Date 2013 07 23 Software User Manual Revision 1 8 2 Reference R077 230rep_01_08_02_Software_User_Manual_Framework doc State Final etamax space GmbH Frankfurter Str 3D 38122 Braunschweig Page 47 176 3 2 1 Geometry File A default geometry file has been created together with the project If you want to add fur ther geometry files choose File New Geometry from the menubar a wizard as shown in the following figure will open Figure 3 8 Geometry file creation wizard On the first wizard page keep Create empty file as option and press Next The second page asks for the new file s location above tc_5_01 and name above cube sat_geometry without file ending Upon pressing Finish the geometry file will be created and the geometry editor opened Geometry files have the file ending geometry which is neither shown in the ESABASE2 Explorer nor specifie
144. on 3 3 Pointing Defines shape pointing e g solar panel to sun See subsection 3 4 Material Defines the material properties of the shapes surfaces Only used in some solvers Some solvers e g Debris COMOVA may introduce additional pages to fulfil their special geometry model requirements These pages will be explained in the respective solver chap ters ESABASE2 Framework Date 2013 07 23 Software User Manual Revision 1 8 2 Reference R077 230rep_01_08_02_Software_User_Manual_Framework doc State Final etamax space GmbH Frankfurter Str 3D 38122 Braunschweig Page 55 176 3 2 3 1 Box Size Page The Add Box command will result in the wizard shown in the following figure Figure 3 15 Geometry editor Box wizard Size page In the upper section you can see object name and state name Usually you can leave them as is future versions of ESABASE2 may support multiple states per object The box definition itself is quite straightforward Choose a size in XYZ dimensions and then specify whether the point of origin is the front lower right corner point or the centre of the box we recommend the former As you can see in the picture marked by the red box it is also possible to supply input pa rameters in GDML style Besides the box the wizard offers this functionality for the sphere the cylinder the ellipsoid and the cone All parameters of the box are described in Annex A Geometry Shape
145. operties view shows the file nodes The menu bar contains File Edit Help entries probably familiar to you from other ap plications and a Window menu which allows you to customize the GUI both through Per spective settings and the Preferences Please see Annex B for details and the following fig ure for overview Figure 2 5 Menubar and Toolbar The toolbar contains New Save Save All and Run buttons The New project ge ometry mission etc entry is explained in section 2 2 3 Project Organisation the Run entries apply to the different Solvers e g Debris Sunlight Atmosphere and are explained in the respective solver handbooks If you hopelessly disarranged the application window you can press the Reset Perspective button as a last resort It will restore the standard GUI settings The Next Prev Change and Back buttons are shortcuts to menu entries They will be removed in future versions of ESABASE2 The editor area contains the active editors Whenever there is more than one editor open tabs will show the list and the active tab belongs to the active editor Please see chapter 3 Mission and Spacecraft definition for details ESABASE2 Framework Date 2013 07 23 Software User Manual Revision 1 8 2 Reference R077 230rep_01_08_02_Software_User_Manual_Framework doc State Final etamax space GmbH Frankfurter Str 3D 38122 Braunschweig Page 25 176 Explorer O
146. or more interaction than just pressing a button each toggle button activates a particular interaction mode Zoom area mode allows to select a rectangular region with the mouse that should be zoomed Normal zoom mode zoom in and out by dragging the mouse Pan mode move the view by dragging it with the mouse Rotate mode rotate the object with the mouse With the first zoom toggle button the zoom area mode is activated Leftclick and hold the mouse in the geometry area and drag a rectangle then release the mouse button The selected area is now the new viewing perspective The second zoom toggle button works differently While this mode is active you can hold the left mouse button and move the mouse to the left or to the right Left means fur ther away right means closing in Using the third toggle button you can pan the perspective Hold the left mouse button and move the perspective with the mouse then release the mouse button The fourth button is used for rotation Within this mode hold the left mouse button and move the mouse cursor to gradually change the rotational viewing angle Date 2013 07 23 ESABASE2 Framework Revision 1 8 2 Software User Manual State Final Reference R077 230rep_01_08_02_Software_User_Manual_Framework doc Page 52 176 etamax space GmbH Frankfurter Str 3D 38122 Braunschweig The last button on the left side of the toolbar is the Select mo
147. orrect Not Correct Correct Cylinder Correct Not Correct Correct Disc Correct Correct Correct Ellipsoid Correct Correct except trun cated and or seg mented ellipsoid Correct Parabole Correct Correct Correct Pipe Correct Not Currect Correct Plate Correct Correct Correct Prism Correct Not Correct Correct Sphere Correct Correct except trun cated and or seg mented sphere Correct Surface Correct Correct Correct Tank Correct Correct Correct Tetrahedron Correct Correct Correct Tessellated Correct most cases Not Correct Not Supported Torus Correct Not Working Not Supported Trapezoid Not Correct Correct Not Supported Truss Not Working Not Correct Correct Table 5 9 Overview of the capabilities of the ESABASE2 meshers 5 4 4 ATI Graphics Card ESABASE2 relies on the OpenCASCASDE visualisation library which uses OpenGL to display all kinds of 3D shapes The OpenGL implementation depends on the used graphics gard and following OpenCASCADE s recommendations we strongly advise to only use ESABASE2 on computers with an NVIDIA graphics card Using it on computers with ATI graphics cards can lead to random crashes and general instabilities Date 2013 07 23 ESABASE2 Framework Revision 1 8 2 Software User Manual State Final Reference R077 230rep_01_08_02_Software_User_Manual_Framework doc Page 128 176 etamax space GmbH Frankfurter
148. ose Import STEP AP in place of the standard Create empty file Then on the next page choose the input STEP file The third page will ask you for a direc tory location the same as for empty new geometries Date 2013 07 23 ESABASE2 Framework Revision 1 8 2 Software User Manual State Final Reference R077 230rep_01_08_02_Software_User_Manual_Framework doc Page 88 176 etamax space GmbH Frankfurter Str 3D 38122 Braunschweig The following figure shows an ATV model imported from a STEP AP 214 file Figure 3 50 Geometry editor imported STEP ATV model The NetGen mesher is stored as default for every object Occasionally a STEP file is struc tured in a way that does not allow NetGen to automatically figure out a good way to mesh it In this case you can change the meshing parameters and or the mesher via the Geometry Wizard for each object Finally please note that only geometrical and topological STEP entities as well as assembly structures are imported into the geometry file This means that you must re specify the fol lowing information Kinematics see 3 2 3 5 Pointing see 3 2 3 6 Both can be done by using the ESABASE2 shape wizard ESABASE2 Framework Date 2013 07 23 Software User Manual Revision 1 8 2 Reference R077 230rep_01_08_02_Software_User_Manual_Framework doc State Final etamax space GmbH Frankfurter Str 3D 38122 Braunschweig Page 89 176 3 2 6 2 BAS File
149. otation of a body may be restricted in range minimum and maximum values to take into account the possible mechanical constraints If two rotational degrees of freedom are defined and there is no constraint on the rotation the pointing is exact However the gen eral case with non orthogonal rotational degrees of freedom does not always allow exact pointing even when no constraint has been defined If one rotational degree of freedom is defined the pointing minimises the angular difference between the pointing vector and the pointing direction required This can be improved by using the degree of freedom of the par ent body to get two effective degrees of freedom In this case both the body and its parent body must have one and only one degree of freedom If for any reason there is no relative rotation between two bodies zero rotational degrees of freedom may be defined Date 2013 07 23 ESABASE2 Framework Revision 1 8 2 Software User Manual State Final Reference R077 230rep_01_08_02_Software_User_Manual_Framework doc Page 102 176 etamax space GmbH Frankfurter Str 3D 38122 Braunschweig 3 4 Pointing Following the briefly discussed Pointing in section 3 2 3 5 and 3 2 3 6 this section goes into deeper detail in the following structure Pointing Introduction Why to use pointing Pointing Parameters How to use pointing Relationship with Mission Specification How pointing and orbit specification work to
150. p system The help system is the same as this user manual Date 2013 07 23 ESABASE2 Framework Revision 1 8 2 Software User Manual State Final Reference R077 230rep_01_08_02_Software_User_Manual_Framework doc Page 176 176 etamax space GmbH Frankfurter Str 3D 38122 Braunschweig 7 2 Geometry Editor Toolbar In the geometry editor the toolbar at the top allows you to select the viewing options The more central buttons were described in section 3 2 2 Additional viewing mode toggle button are shown by the following figure Figure 7 3 Geometry editor Toolbar right side You have the choice among the following viewing options Line Wireframe mode The objects are displayed using lines Solid mode The objects are displayed coloured with solid faces Background colour Change the background colour of the view from black to anything else You can also change the colour of the colour scale Light on off Enable or disable the lighting of the scene Lighting lets models look more realistic but will obstruct exact object colouring
151. port Interfaces 93 3 3 Kinematics 99 3 3 1 Bodies 100 3 3 2 Degrees of Freedom 100 3 3 3 The Central Body 101 3 3 4 Articulated Bodies 101 3 4 Pointing 102 3 4 1 Pointing Introduction 102 3 4 2 Pointing Parameters 104 3 4 3 Relationship with Mission Specification 110 3 4 4 Pointing the Bodies and Indeterminacies 113 3 4 5 Pointing Output 116 3 4 6 Pointing Calculation Method 117 4 Solvers
152. pplications and the pointing facility need to know the position of a space craft on its orbit at successive times during an analysis For the purpose of generating this information in a standard form an orbit generator is provided with ESABASE2 The orbit generator currently used is SAPRE The SAPRE orbit generator uses a 4th order Runge Kutta routine with fixed step size to inte grate the equations of motion expressed in terms of osculating orbital elements It is a gen eral purpose orbit generator and may be used for close earth orbits geostationary orbits or highly eccentric orbits It was also extended to allow the use for lunar orbits Facilities exist for taking into account the first few harmonics of the earth s respective Moon s gravitational field perturbations due to the Sun s and Moon s for Earth respective Earth s for Moon gravity fields air drag for Earth using the CIRA atmospheric density model 1965 and solar radiation pressure for Earth The input to SAPRE is the orbit specified via the mission editor The orbital elements are specified in a standard format and control parameters and details of perturbing influences to be modelled can be specified in the respective Outline window see Figure 3 3 The output is saved for each orbital point in the result file and gives the position and velocity of the spacecraft at specified intervals and also upon eclipse entry and exit This information is read by the applicatio
153. r 3D 38122 Braunschweig The version 3 provided only the ESABASE mesher A new feature can be very helpfully if the ESABASE mesher shall be applied to the objects again To use the feature select an object it is not applicable to system in the Outline and choose in the context menu Apply ESABASE mesher includes all child objects see next figure This applies the ESABASE mesher with default meshing configu ration to the object and its child objects Figure 5 4 Application of the ESABASE mesher in the Outline It is recommended that the user should manually mesh the geometry using the Netgen mesher before performing the export to a GDML file The following table shows which shape is meshed correctly with which meshers in ESABASE2 The table uses the following terms to describe the meshing behaviour Correct The element normal is pointing to the correct direction Not Correct The element normal is not pointing to the correct direction Not Working The mesher does not work correctly for this shape Not Supported The shape is not supported by the mesher ESABASE2 Framework Date 2013 07 23 Software User Manual Revision 1 8 2 Reference R077 230rep_01_08_02_Software_User_Manual_Framework doc State Final etamax space GmbH Frankfurter Str 3D 38122 Braunschweig Page 127 176 Shape Netgen OCC ESABASE Beam Correct Not Correct Correct Box Correct Correct Correct Cone C
154. r and inner paraboloid base and top disc cut faces at angle1 and angle2 For a basic cylinder full cylinder in ESABASE style only three parameters need to be speci fied Parameter p1 defines the centre point of the base of the cylinder p2 defines the centre point of the top of the cylinder and diam defines the diameter of the base of the cylinder Because no more parameters are defined the cylinder will be a full and complete cylinder ESABASE2 Framework Date 2013 07 23 Software User Manual Revision 1 8 2 Reference R077 230rep_01_08_02_Software_User_Manual_Framework doc State Final etamax space GmbH Frankfurter Str 3D 38122 Braunschweig Page 137 176 By default the cylinder is a solid cylinder thick is empty To change this the user can de fine the thickness of the walls of the cylinder thick If the thickness is 0 the walls are infinitely thin Then diam is the external diameter of the base of the cylinder For a basic cylinder in GDML style only two parameters need to be specified Parameter rMax defines the radius of the base of the cylinder and parameter dZ defines the half height of the cylinder If the parameter rMin was greater than 0 the cylinder will be hollow The inner radius is rMin In order to segment the cylinder in ESABASE style the user needs to specify p3 angle1 and angle2 The point p3 together with p1 and p2 defines the plane which serves as start ing point for the
155. ral body will then be used to minimise the angular difference between the pointing vector and the required pointing direction of that attached body this attached body must itself have one degree of freedom The other bodies require a pointing vector and direction for each degree of freedom the VEC1 and direction parameters respectively Date 2013 07 23 ESABASE2 Framework Revision 1 8 2 Software User Manual State Final Reference R077 230rep_01_08_02_Software_User_Manual_Framework doc Page 106 176 etamax space GmbH Frankfurter Str 3D 38122 Braunschweig 3 4 2 2 Inherit Parent Values This parameter is accessible via the check box Inherit parent values on the Pointing page Parameter Type Range Default Description parent boolean 0 or 1 0 is a flag to indicate whether the free degree of freedom of the parent body will be used to minimise the angle between the pointing vector and the pointing di rection of the current body Table 3 3 The Inherit parent values parameter Parent may be specified only if The body is not the central body The body must have one and only one rotational degree of freedom and at least one VEC parameter The parent body if central body has no VEC2 specified The parent body if not central body must have one and only one rotational degree of freedom and may not have a VEC1 parameter Only one body can be attached to the parent body using the In
156. rdinates x y z These points are the centres of the ends of the truss Additionally the size1 which specifies the length of the side of the truss and nstep which is the number of elementary sections that the shape is constructed of have to be defined Furthermore p3 which defines the orientation of the truss and size2 which is the size of the other side of the cross section of the truss can be defined If size2 is not specified it defaults to size1 6 4 4 2 3 Meshing A meshing parameter cannot be applied to a TRUSS3 or TRUSS4 object Date 2013 07 23 ESABASE2 Framework Revision 1 8 2 Software User Manual State Final Reference R077 230rep_01_08_02_Software_User_Manual_Framework doc Page 174 176 etamax space GmbH Frankfurter Str 3D 38122 Braunschweig 7 Annex B Additional GUI Elements This annex describes GUI elements which are not central to the usage of ESABASE2 and therefore have not been included in either the mission geometry or solver chapters In par ticular these are Application Menubar A complete listing of menubar options Geometry Editor Toolbar Additional options in the toolbar e g for lighting or wire frame mode 7 1 Application Menubar The menu bar contains mostly predictable entries as the following figure shows only the Window menu will probably seem unfamiliar to you Figure 7 1 ESABASE2 menu bar The File menu contains the usual New Open
157. rently selected entity It is restricted to entities which are not referenced by other entities and which are not assigned to surfaces in the case of materi als Button Copy to The Copy to button allows the user to copy an entity from the ESABASE2 material library into the geometry and vice versa If an entity with the same name already exists in the tar get tree the user has to confirm the overwrite process When an entity with child entities gets transferred the child entities get transferred as well E g a material composed of two elements getting copied results in the two elements getting transferred as well Button Set type Materials can have three types atomic made of composites or made of fractions This but ton enables you to toggle between these types Initially a new material is considered atomic When you add a fraction or composite as a child to this material you have the option to switch the type Select the Fractions or Composites node and use the Set material type button appropriately Button Collapse This button enables you to close the library or geometry tree whichever is currently se lected ESABASE2 Framework Date 2013 07 23 Software User Manual Revision 1 8 2 Reference R077 230rep_01_08_02_Software_User_Manual_Framework doc State Final etamax space GmbH Frankfurter Str 3D 38122 Braunschweig Page 67 176 Button Filter If a material is
158. rk Date 2013 07 23 Software User Manual Revision 1 8 2 Reference R077 230rep_01_08_02_Software_User_Manual_Framework doc State Final etamax space GmbH Frankfurter Str 3D 38122 Braunschweig Page 95 176 Figure 3 58 Files generated during GDML export In detail the main file is a GDML file that refers to other exported files from its several sec tions This way e g the position information is stored separated from the shape information This is done via XML entities So when reading the GDML file with a standard conform XML parser the entities are included during reading This way a program like Geant4 can operate on the full GDML data structure The advantage of this split storage appears in case of large exports It requires a smaller amount of memory during export and prevents from crashes due to out of memory errors The typical content of a mainFile gdml is shown in Figure 3 59 Figure 3 59 Typical content of mainFile gdml Date 2013 07 23 ESABASE2 Framework Revision 1 8 2 Software User Manual State Final Reference R077 230rep_01_08_02_Software_User_Manual_Framework doc Page 96 176 etamax space GmbH Frankfurter Str 3D 38122 Braunschweig 3 2 7 2 STEP SPE Export With release 5 0 of ESABASE2 it is possible to export geometry objects to files following the STEP SPE protocol The export mechanism for STEP SPE follows the same principles as the GDML export de scribed
159. roid models refer to the Debris handbook Information whether the system is in eclipse or not is derived from the epoch parameters time location velocity and eclipse flag 3 4 3 2 Space Orientation The orientation in space of each body of the articulated system is described by A body fixed pointing vector A pointing direction in a specified orbital reference frame A pointing direction may be specified in one of the following reference frames INERTEQ geocentric inertial equatorial system o x within the equatorial plane towards the vernal equinox o z perpendicular to equatorial plane towards North o y completes the right hand system x y z o Note INERTEQ is the so called GAMMA 50 reference frame ESABASE2 Framework Date 2013 07 23 Software User Manual Revision 1 8 2 Reference R077 230rep_01_08_02_Software_User_Manual_Framework doc State Final etamax space GmbH Frankfurter Str 3D 38122 Braunschweig Page 111 176 INERTEC geocentric inertial ecliptic system o x within the ecliptic plane towards the vernal equinox o z perpendicular to ecliptic plane towards ecliptic North pole o y completes the right hand system x y z SUNEQ geocentric sun fixed equatorial system o x within the equatorial plane towards the intersection of the meridian of the true sun with the equator o z perpendicular to equatorial plane towards North o y completes the right hand system x y z SUN
160. rs We recommend creating one project per mis sion To do so click File New Project in the menubar the wizard shown in the follow ing figure will open Figure 2 8 New Project wizard page 1 On this first page you can select the type of project choose ESABASE2 Project in future versions of ESABASE2 other kinds of project may be possible Then click next This will lead to the second wizard page illustrated in the following figure Date 2013 07 23 ESABASE2 Framework Revision 1 8 2 Software User Manual State Final Reference R077 230rep_01_08_02_Software_User_Manual_Framework doc Page 28 176 etamax space GmbH Frankfurter Str 3D 38122 Braunschweig Figure 2 9 New Project wizard page 2 Choose a project name in the first text field we recommend lt S C name gt _project Then click the Finish button When looking at the ESABASE2 Explorer top left in the window you will see that the pro ject has been created with three default files shown in the following figure Figure 2 10 A new project and its three default files The geometry file contains the S C geometry the mission file describes the orbit and the debris solver input file contains parameters for ESABASE2 Debris ESABASE2 Framework Date 2013 07 23 Software User Manual Revision 1 8 2 Reference R077 230rep_01_08_02_Software_User_Manual_Framework doc State Final etamax space GmbH Frankf
161. s For our purposes set 100 mm as side length and press Next If you enter invalid values the appropriate fields will become red Please note that for some more complex shapes certain errors can only be detected after you press Finish these are errors related to surface generation and meshing which is only done once for performance reasons In that case a popup dialog will inform you and you have to revisit the wizard in order to correct the values Date 2013 07 23 ESABASE2 Framework Revision 1 8 2 Software User Manual State Final Reference R077 230rep_01_08_02_Software_User_Manual_Framework doc Page 56 176 etamax space GmbH Frankfurter Str 3D 38122 Braunschweig 3 2 3 2 Box Meshing Page The following figure shows the meshing page which has the same structure for all shapes but differing default parameters Figure 3 16 Geometry editor Box wizard Meshing page On the meshing page you can fine tune the subdivision of surfaces of the object which may be curved into meshed elements which are planar triangles or quads The normal case is to accept the defaults Up to three meshers are available for the shapes the ESABASE NetGen and OCC mesher How many meshers are available for a shape depends on the type of shape For the shapes from the original ESABASE shape palette all three meshers are available For Torus Tetra hedron and Trapezoid only the NetGen and OCC meshers can be use
162. s the external diameter of the base of the cone For a basic cone in GDML style only two parameters need to be specified Parameter rMax1 defines the radius of the base of the cone and parameter dZ defines the half height of the cone If the parameter rMin1 was greater than 0 the cone will be holed The radius of the hole is rMin1 To define a cone which is truncated parallel to the base in ESABASE style the parameter diam2 has to be defined If diam2 was 0 it would be a basic cone with a sharp apex To define a truncated cone in GDML style the parameter rMax2 has to be greater than 0 The parameter rMax2 defines the radius of the apex In order to segment the cone in ESABASE style p3 angle1 and angle2 need to be speci fied The point p3 together with p1 and p2 define the plane which serves as a starting point for the angles Going from that point angle1 defines the start and angle2 defines the end of the segment around the axis p1 p2 To segment the cone in GDML style sPhi and dPhi have to be specified Parameter sPhi de fines the start angle and parameter dPhi defines the size of the segment 6 1 2 3 Meshing The meshing parameters are expressed along the meshing directions a b c refer to the figures above ESABASE2 Framework Date 2013 07 23 Software User Manual Revision 1 8 2 Reference R077 230rep_01_08_02_Software_User_Manual_Framework doc State Final etamax space GmbH Frankfurter S
163. st version of central DLLs used by ESABASE2 ESABASE2 Framework Date 2013 07 23 Software User Manual Revision 1 8 2 Reference R077 230rep_01_08_02_Software_User_Manual_Framework doc State Final etamax space GmbH Frankfurter Str 3D 38122 Braunschweig Page 21 176 2 1 4 Upgrade If you are a first time user of ESABASE2 you can safely skip this chapter If you are upgrad ing the following hints may be useful for you The new installation is in a separate directory from your old installation It is possible to have several versions on harddisks the development team is doing it all the time To keep your workspace from a previous version e g ESABASE2 1 4 2 delete the workspace directory from the new application directory and move your original workspace directory here Then start the new application your workspace should be immediately visible This is all you need to do to the workspace replacement Individual projects can be imported also by copying the project folder or files to the existing workspace directory After starting the application the project files should be visible Please note that with ESABASE2 version 2 0 0 a new file storing format has been intro duced Files from earlier versions are readable they are converted automatically to the new version but it is not possible the other way round For example a geometry file created or modified with ESABASE2 version 4 0 0 will not be re
164. t of the meshing into nodes and elements Note p3 must be specified if angle1 angle2 angle3 or diame is specified angle1 real deg 0 lt angle1 lt an gle2 lt 360 0 Start angle with reference to the plane p1p2p3 for generating a segment angle2 real deg 0 lt angle1 lt an gle2 lt 360 360 End angle with reference to the plane p1p2p3 for generating a segment Table 6 5 Definition of the CYLINDER shape in ESABASE style Parameter Type Unit Range Description rMin real mm 0 The inner radius of the circular cylinder rMax real mm gt 0 The outer radius of the circular cylinder sPhi real deg 0 dPhi 360 Starting angle of the segment in radians in x y dimension dPhi real deg 0 lt dPhi 360 sPhi Size angle of the segment in radians in x y dimension dZ real mm gt 0 Half height of the cone in z direction Table 6 6 Definition of the CYLINDER shape in GDML style 6 1 3 2 Geometry and Size This shape describes a circular cylinder or a segment of a cylinder The cylinder may be a volume or a surface By default the complete boundary surface of the shape is active For a surface shape only one side of the boundary surface can be made active by changing this default via the respec tive drop down menu on the Meshing page of the shape wizard Depending on the shape s parameter values the shape s boundary surface has up to 6 faces oute
165. t geometry definition as well as a solver specific input file In this chapter you will learn how to specify mission and S C geometry in the following steps Mission How to specify the S C orbit and timeframe of the mission Geometry How to build a 3D spacecraft geometry in a CAD way or how to import one from BAS or STEP files Kinematics How to supply the S C geometry with the ability to move its parts both by rotating and translating subsystems during a mission Pointing How to specify pointing on a spacecraft both on the system and on sub components e g solar panels pointing to the sun Subsystems need kinematics to be able to move 3 1 Mission All solvers within ESABASE2 perform their analysis on orbital points i e fixed locations on a given orbit at a given point of time To determine these orbital points the mission file is used In the following you will specify a mission in the following steps Mission File How to create a new mission file Mission Editor How to specify the orbit timeframe and orbital point parameters Mission Outline and Properties View How to specify additional parameters for Expert users only Mission Visualisation The mission editor contains a preview page on which you can see the specified orbit Import of INP files Alternatively you can import original ESABASE INP files for the mission specification Orbit Propagator Explains how the orbit propagator works and its
166. tform attitude obtained by a rotation about the p axis Figure 3 65 Attitude indeterminacy central body The central body has 3 degrees of freedom The exact pointing of p towards the earth re moves 2 degrees of freedom The remaining degree of freedom is the rotation about the p axis To fully determine the orientation of the spacecraft the remaining degree of freedom must be removed This may be achieved by specifying a second pointing vector VEC2 and a pointing direction pdir The central body is then rotated about p such that the pointing vec tor given in VEC2 is aligned as closely as possible with the direction given in pdir The second method is to let an attached body use this degree of freedom to achieve the orientation of the pointing vector which has the minimum angular deviation from the speci fied direction for itself i e the central body will be rotated about p such that the pointing vector of the attached body achieves the minimum angular deviation from its specified point ing direction ESABASE2 Framework Date 2013 07 23 Software User Manual Revision 1 8 2 Reference R077 230rep_01_08_02_Software_User_Manual_Framework doc State Final etamax space GmbH Frankfurter Str 3D 38122 Braunschweig Page 115 176 A second pointing vector VEC2 is used to suppress the indeterminacy about the first pointing vector If this second pointing vector is not defined the first pointing vector be
167. the earth the body can continue tracking or stop in its latest position according to the value of the track flag Parame ter Type Range Default Description ESABASE2 Framework Date 2013 07 23 Software User Manual Revision 1 8 2 Reference R077 230rep_01_08_02_Software_User_Manual_Framework doc State Final etamax space GmbH Frankfurter Str 3D 38122 Braunschweig Page 109 176 Parame ter Type Range Default Description track boolean 0 or 1 1 Flag to specify the behaviour of the pointing vector when the pointing direc tion is eclipsed by the earth Table 3 7 The track parameter Use track if the pointing vector is to continue tracking the pointing direction Disable track if the pointing vector is to retain the last orientation before eclipse until no longer eclipsed Even if exact pointing can be realised it may be of no use when the pointing direction is eclipsed by the earth In this case either the pointing vector of the body continues to track the pointing direction or the body stays in its last position 3 4 2 7 Inverse The inverse parameter is accessible via the check box on the Pointing page of the ge ometry wizards Parameter Type Range Default Description inverse boolean 0 or 1 0 Flag to indicate which body orientation to choose if two pointing solutions ex ist If inverse 0 the first solution is chosen If inverse 1 the second solu tion is chosen
168. the ends of the beam By default the beam is a line segment By using the optional size parameter the length of the sides of the square cross section of the beam can be specified BEAM is classed as a line shape and hence has no surface nodes It is not considered in sur face related analyses 6 4 1 3 Meshing Note that although the shape has one or more node areas it has no surface nodes as the shape is classed as a line shape The meshing parameter a intersects the beam into a sec tions of equal length Date 2013 07 23 ESABASE2 Framework Revision 1 8 2 Software User Manual State Final Reference R077 230rep_01_08_02_Software_User_Manual_Framework doc Page 164 176 etamax space GmbH Frankfurter Str 3D 38122 Braunschweig 6 4 2 Pipe Figure 6 21 Parameters of a pipe object Parameter Type Unit Range Default Description p1 p2 p3 pn point mm mm mm Corner points of the pipe Note up to 64 points may be specified size real mm 0 0 the pipe is a series of line segments Length of the sides of the cross section of the pipe Table 6 18 Definition of the PIPE shape 6 4 2 1 Geometry and Size This shape describes a square section pipe between the points p1 and p2 where p1 and p2 are the centre points of the ends of the pipe By default the pipe is a line segment By using the optional size parameter the length of the sides of the square cross section of
169. the pipe can be specified PIPE is classed as a line shape and hence has no surface nodes It is not considered in sur face related analyses ESABASE2 Framework Date 2013 07 23 Software User Manual Revision 1 8 2 Reference R077 230rep_01_08_02_Software_User_Manual_Framework doc State Final etamax space GmbH Frankfurter Str 3D 38122 Braunschweig Page 165 176 In order to define a pipe the user must specify multiple points defined with coordinates x y z The pipe shape is a shape that will be created by connecting these points At least two points p1 and p2 have to be specified Additionally the thickness of the pipe size in mil limetres needs to be defined By default the thickness is 0 6 4 2 2 Meshing The meshing direction is from P1 to P8 as shown in the example in Figure 6 21 Note that although the shape has one or more node areas it has no surface nodes as the shape is classed as a line shape Date 2013 07 23 ESABASE2 Framework Revision 1 8 2 Software User Manual State Final Reference R077 230rep_01_08_02_Software_User_Manual_Framework doc Page 166 176 etamax space GmbH Frankfurter Str 3D 38122 Braunschweig 6 4 3 Tank Figure 6 22 Parameters of a tank object 6 4 3 1 Purpose To describe the shape of a tank consisting of a cylindrical mid section and two hemispheri cal end caps Parameter Type Unit Range Default Description p1 point
170. tion 1 0 0 in the SUNEC reference frame SUN The body is pointing towards the sun This is equivalent to direction 1 0 0 in the SUNEC reference frame VELOCITY The body is pointing within the orbital plane along the absolute velocity vec tor This is equivalent to direction 0 1 0 in the ORBITT reference frame GEORELAY The body is pointing towards a geostationary entity whose location is specified by its georelay longitude FIXED The body is fixed For the central body it implies that the orientation is fixed in inertial space at the last value For all other bodies it implies that they are rigidly connected to their parent body If fixed is used then track may not be specified FRAME The body s pointing direction is specified by a vector in an orbital reference frame The vector may be specified by its coordinates or as right ascension and declina tion The orbital reference frame may be inertial INERTEQ INERTEC sun based SUNEQ SUNEC earth based EARTHE EARTHG or orbit related ORBITG ORBITT CENTRAL BODY If a complete lunar mission is analysed via an appropriate trajectory file the central body for the first part of the mission is the Earth When the space craft reaches a certain point of the orbit the central body becomes the Moon To reflect this and allow this kind of flexibility in the pointing this frame should be used 3 4 2 6 Track When a pointing direction of a body is eclipsed by
171. tline the corresponding properties view shows for the panel the x y z size and the box thickness The attributes you see here will appear familiar These are the ones that you already edited in the Shape Wizard on the size page see 3 2 3 1 Please note that the amount of nodes and attributes you see in the Outline and Properties view depend on the user level setting made in the preferences in the menubar choose Window Preferences then adjust user mode The default setting is Normal where not all information is displayed With the Expert setting you can see more nodes and attributes Finally the Developer setting may not be available in some versions shows everything but enables you to crash the application in creative ways if you change data values see next subsection wrongly Date 2013 07 23 ESABASE2 Framework Revision 1 8 2 Software User Manual State Final Reference R077 230rep_01_08_02_Software_User_Manual_Framework doc Page 82 176 etamax space GmbH Frankfurter Str 3D 38122 Braunschweig 3 2 4 4 Shape Editing Outline and Properties view not only enable you to see that data within a spacecraft geome try but also give you the opportunity to edit attributes directly Leftclick on a value in the Properties view to activate editing as shown in the following figure Figure 3 42 Geometry editor Outline and Properties view editing On the left side you see a red circle for the
172. to keep the framework handbook at a reasonable size the chapters for the solvers have been put into dedicated solver handbooks The Debris handbook 2 covers space debris and micro meteoroids The Atmosphere Ionosphere handbook 3 covers atmospheric and ionospheric ef fects it corresponds to the Atomic Oxygen solver of the original ESABASE The COMOVA handbook 4 covers contamination and outgassing The Sunlight handbook 5 covers sunlight effects In each handbook input and output files as well as instructions for running an analysis are described Geometry additions only applicable for one specific solver are also covered there including more detailed material descriptions Date 2013 07 23 ESABASE2 Framework Revision 1 8 2 Software User Manual State Final Reference R077 230rep_01_08_02_Software_User_Manual_Framework doc Page 120 176 etamax space GmbH Frankfurter Str 3D 38122 Braunschweig 5 Troubleshooting You can run into two kinds of trouble The application delivers unexpected results or the application crashes This chapter is divided into the following sections Precautions How to avoid trouble Trouble Information Where to look for information about what is happening Application Messages How to interpret warnings and errors shown by the application Known Issues How to recognize and work around known problems 5 1 Precautions The following precautions can be taken to avoid
173. tr 3D 38122 Braunschweig Page 135 176 6 1 3 Cylinder Figure 6 4 Parameters of a cylinder object in ESABASE left and GDML right style 6 1 3 1 Purpose To describe the shape of a circular or elliptical cylinder or a sector of a cylinder of a given wall thickness Parameter Type Unit Range Default Description p1 point mm mm mm Location of the centre of the base of the cylinder and the first point of the axis of revolution p2 point mm mm mm Location of the centre of the top of the cylinder and the second point of the axis of revolution defined by the vector p1p2 diam real mm gt 0 External diameter of a circular cylinder or the diameter of an elliptical cylinder perpendicular to the plane p1p2p3 thick real mm 0 lt thick lt diam 2 solid cylin der Wall thickness of the cylinder If thick 0 the shape is a sur face p3 point mm mm mm Point defining the plane p1p2p3 The intersection of this plane with the cylinder acts as the Date 2013 07 23 ESABASE2 Framework Revision 1 8 2 Software User Manual State Final Reference R077 230rep_01_08_02_Software_User_Manual_Framework doc Page 136 176 etamax space GmbH Frankfurter Str 3D 38122 Braunschweig Parameter Type Unit Range Default Description reference line for generating a segment and for specifying the direction of diame and also for specifying the starting poin
174. trouble Have as much RAM as possible gt 2 GB Install the latest graphics card driver OpenGL support must be available o nvidia http www nvidia com Download index aspx o ati http ati amd com support driver html If you have an older graphics card or driver avoid using two or more monitors Use Nvidia or ATI graphics cards Particularly Intel or SiS graphics cards are not sup ported Their OpenGL implementations are incomplete 5 2 Trouble Information There are several ways to retrieve information When the application opens an error dialog please make a screen shot Alt PrtScr then paste into ImageMagick Word or another program capable of handling images The ESABASE2 log file is another valuable source of information You can find it un der the logs directory in the installed application directory Each application start pro duces a new log file the current date and time is part of the file name When reporting errors to us please attach log files and a screenshot of the error message This will shorten our error reproduction and debug times considerably ESABASE2 Framework Date 2013 07 23 Software User Manual Revision 1 8 2 Reference R077 230rep_01_08_02_Software_User_Manual_Framework doc State Final etamax space GmbH Frankfurter Str 3D 38122 Braunschweig Page 121 176 5 3 Program Messages Error messages of the different modules of the software are issued to different pla
175. ual State Final Reference R077 230rep_01_08_02_Software_User_Manual_Framework doc Page 18 176 etamax space GmbH Frankfurter Str 3D 38122 Braunschweig 2 Getting Started with ESABASE2 This chapter describes how you can install and run ESABASE2 in a basic way If you have already created a spacecraft geometry and a mission and or made an analysis you can safely skip this chapter It is divided into the following subsections Installation and Start How to install ESABASE2 and start it you should end with the application on your screen Basic GUI Usage Explanation of the ESABASE2 graphical user interface concept how to perform tasks that are common to all ESABASE2 solvers 2 1 Installation and Start In this section you will learn how to install and start ESABASE2 Hardware Requirements Just to make sure your PC is sufficiently powerful Especially large geometries and many orbital points can be quite taxing Installation How to install the ESABASE2 software on your harddisk Operating System Adaptations For older operating systems e g Windows 2000 some adaptations are necessary in order to run ESABASE2 Upgrade Notes for users upgrading from a previous version of ESABASE2 Starting ESABASE2 The different ways to start the application and details about where your files are on the harddisk 2 1 1 Hardware Requirements Before installing ESABASE2 you should make sure that the system requirements listed
176. ure that the model will be cor rectly imported A second issue is the use of SHIFT and MIRROR Although shapes are correctly imported you should not change their values afterwards depending on the order of BAS commands different non intended effects could happen Besides as of ESABASE2 4 0 MIRROR is no longer supported even if not used in combination with shift A third issue are unsupported constructs affecting the system and object sections In the system section only DATA is supported all other constructs are ignored ENCLOSURE NODE SUBSYSTEM TEXT ESABASE2 Framework Date 2013 07 23 Software User Manual Revision 1 8 2 Reference R077 230rep_01_08_02_Software_User_Manual_Framework doc State Final etamax space GmbH Frankfurter Str 3D 38122 Braunschweig Page 125 176 In the object section the following constructs are unsupported and thus ignored ANALYSIS except RAYDENS which is imported MASS within RADIATION INCLUDE is not supported because it requires MASS TEXT Some sections like RADIATION currently do not have a solver The information is imported anyway and you can access it via the Outline and Property editor see 3 2 4 but it will not be of any use 5 4 2 Memory Leak caused by Open CASCADE Open CASCADE provides its own memory management which causes minor memory leaks in connection with ESABASE2 geometry handling The consequence is cumulating memory all
177. urter Str 3D 38122 Braunschweig Page 29 176 2 2 3 2 Creating Input Files When you created a project 3 default files for S C geometry mission specification and De bris solver were created To create additional files choose File New lt Type gt in the menubar as illustrated by the following figure Figure 2 11 Creating new files within a project All possible input files are listed here In the example above you see New options for pro jects see previous subsection geometry mission folder and solver input files for Atmos phere Ionosphere and Debris For each file type an appropriate wizard will be opened at the minimum it will ask you for the filename and where to save it in the project structure Import options if applicable will also be presented here please see the respective chapters for more information All newly created input files are filled with default values such that you can immediately per form a solver run with it This means that with the 3 default files you could initiate an ESABASE2 Debris analysis see Debris solver handbook Date 2013 07 23 ESABASE2 Framework Revision 1 8 2 Software User Manual State Final Reference R077 230rep_01_08_02_Software_User_Manual_Framework doc Page 30 176 etamax space GmbH Frankfurter Str 3D 38122 Braunschweig 2 2 3 3 Moving Files Around In larger projects you may wish to organise your input and output files into f
178. utline and Properties view give you information about the data contents in a file This is done in 3 detail levels as the following figures show Figure 2 6 Explorer Outline Properties view The Explorer shows the workspace with projects directories and files the Outline shows the tree structure of an open file and the Properties view shows detailed data entries of one specific node In the above example a ROSAT geometry is shown see Explorer This in turn consists of a tree with a System and a main body ROSAT which has a CentralBody with a STATE_1 describing an Axis see Outline To see exactly how the axis is specified refer to the Prop erties view which shows e g a Rotation attribute Date 2013 07 23 ESABASE2 Framework Revision 1 8 2 Software User Manual State Final Reference R077 230rep_01_08_02_Software_User_Manual_Framework doc Page 26 176 etamax space GmbH Frankfurter Str 3D 38122 Braunschweig 2 2 2 GUI Adaptation In this section you will learn how to customise the views of the ESABASE2 application win dow If you are already familiar with GUI handling of multi window applications you can safely skip this chapter The first thing to know is how to manipulate the views within the main application window For this purpose each view has a tab with its name and additional buttons as shown in the following figure Figure 2 7 Common View buttons To the right the first
179. will concentrate on purely local pointing i e the satellite orientation is fixed when seen from the local shape A satellite panel is a good candidate for local pointing Select the main body box in the 3D view and open the context menu to choose Add child Cylinder On the size page set p1 0 0 0 p2 0 30 0 and diam 20 mm On the position and attitude page set translation 50 100 50 This will centre the cylinder on the left side of the satellite when looking from the back This cylinder is the moving part within the solar panel so we specify Kinematics and Pointing on this shape The following figure shows the Kinematics page in the wizard Figure 3 32 Geometry editor Kinematic page solar panel As we can see in the local coordinate system of the cylinder we want to rotate around the y axis Therefore in the first line of the rotation section of the Kinematics page set the rota tion vector to 0 1 0 rmax 360 and rmin 0 In the second line to define where exactly 0 is choose 1 0 0 which is the vector along the x axis pointing into the velocity direction Date 2013 07 23 ESABASE2 Framework Revision 1 8 2 Software User Manual State Final Reference R077 230rep_01_08_02_Software_User_Manual_Framework doc Page 74 176 etamax space GmbH Frankfurter Str 3D 38122 Braunschweig Having specified the kinematics we go to the Pointing page to specify the vector that

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