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1. The Surface platform processing could recognize fingers tags and blobs Figure 1 below shows the Microsoft Surface table and its inner configuration www ljsrp org International Journal of Scientific and Research Publications ISSN 2250 3153 Volume 3 Issue 3 March 2013 Figure 1 Schematic of Microsoft s Surface The parts of the surface table are as follows a Acrylic tabletop touch surface with a diffuser b 850nm infrared light source directed at the underside of the touch surface c Infrared camera d Texas Instrument s DLP projector e Desktop computer running a customized version of Microsoft Vista Source Microsoft 2 Community core vision CCV A Project by Natural User Interface NUI Group Community Core Vision is an open platform solution for computer vision and machine sensing It takes an video input stream and outputs tracking data e g coordinates and blob size and events e g finger down moved and released that are used in building multi touch applications CCV can interface with cameras and video devices as well as connect to various TUIO enabled applications Community Core Vision 25 Figure 2 Screenshot of the CCV Software shows the detection of blob right and image seen by infrared camera left 3 Thin Sight A Multi touch detection approach by Microsoft Research uses the lots of sensors lying on the surface of the touch panel This sensor matrix is placed j2. The Green pads are the Drillable points like IC Pins Burg Strip pins Figure 13 PCB Design Layout for the Sensor Module International Journal of Scientific and Research Publications ISSN 2250 3153 Volume 3 Issue 3 March 2013 APPENDIX B Bill of Materials List of the components used in our design are as follows Table III Bill of Materials Component Manufacturer Total cost in Rupee SN74LS165A 6 TSOP1738_ Visby 1000 Totalcot INR 2378 _ REFERENCES Background Papers Journals 1 Hrvoje Benko Andrew D Wilson Patrick Baudisch Precise Selection Techniques for Multi Touch Screens CHI 2006 Proceedings Interacting with Large Surfaces April 22 27 2006 Montr al Qu bec Canada 2 Shahram Izadi Steve Hodges Alex Butler Alban Rrustemi and Bill Buxton Thin Sight Integrated Optical Multi touch Sensing through Thin Form factor Displays Microsoft Research Cambridge 2007 3 Hofer R Naeff D and Kunz A 2009 FLATIR FTIR multi touch detection on a discrete distributed sensor array Proc TEI 2009 Datasheets 4 IR 908 Infrared LED User manual http www embeddedmarket com storeresources NN 264 user 20manual pdf 5 Tsop 1738 Infrared sensor Vishay http www datasheetcatalog org datasheets 208 301092_DS pdf 6 STELLARIS ARM CORTEX M3 LM3S9D92 Texas Instruments www ti com lit ds symlink Im3s9d92 pdf 7 SN74125 Quardruple bus
3. and then those images will create video as seen before Now then after we need to use the video for making synchronism with mouse movements using procedure as in Section I C 6 and Section I C 7 This whole task is enough to provide a sufficient processing delay thus deteriorating the reliability of the touch detection system So by considering speed as a factor Stellaris ARM Cortex M3 was really an intelligent choice One more point of advantage that it has that there are lots of serial communication channels and many GPIO are also present so interfacing limitations never came on our way 3 Schematics This section shows the two schematics of the sensor module and the IR LED which form the Touch Panel Figure 8 shows the Infrared sensor array with 8 Infrared sensors placed in an array and is connected to a Shift register which takes the 8 bit data from the array of sensors and output them to the microcontroller in the serially padded bits Figure 9 shows the Infrared LED supplied with a 38 KHz signal from microcontroller using the PWM channel through the D Flip Flop and Tri state bus buffer ENABLE SIGNAL 38 KHz SIGNAL D FLIP FLOP TRI STATE BUFFER INPUT FROM 1 0 PORT CLOCK INPUT Figure 9 Infrared Emitter LED International Journal of Scientific and Research Publications ISSN 2250 3153 Volume 3 Issue 3 March 2013 4 High level design SINGLE SENSOR MODULE FOR TOUCH PANEL IR
4. Emitter IR 908 Actuated by the Eight Infrared Sensors Tristate Buffer Clock E providing 8 bit data to 7416125 i Shift Register 38 KHz Modulated signal 7 Q Output SHIFT LOAD R 8 BIT PISO Shift D Flip Flop 7416179 Register Test Input LLU Synchronous serial Interface SSI el Stellaris ARM Cortex M3 TIMER PWM PULSE USB Port USB Controller COMPUTER SOFTWARE IMPLEMENTATION OF THE IMAGE AND VIDEO MAKING ALGORITHM AND SYNCHRONISM WITH MOUSE CONTROL Figure 10 Top level block diagram NOTE The Sensor Module depicted in this diagram is just a single module Many modules combined altogether in daisy chained architecture constitute Touch Panel Refer to Figure 11 Clock noun HIERARCHY OF THE SYSTEM DESIGN LEVEL 1 SENSOR DATA ACQUISITION LEVEL 2 SERIAL INTERFACE LEVEL 3 DIGITAL PROCESSING LEVEL 4 COMPUTER PROCESSING AND MOUSE CONTROL AND SYNCHRONISM ARCHITECTURE International Journal of Scientific and Research Publications ISSN 2250 3153 Volume 3 Issue 3 March 2013 5 Physical arrangement of the Touch panel a Touch Panel The touch panel shown below in Figure 11 shows the sensor based touch panel which consists of many Sensor Modules each having one IR LED and 8 IR Sensor The 8 1 ratio between receivers and LEDs was chosen as a compromise between 20h
5. Initialize the AVI_T a variable for AVI Output file and also the BMP Structure for the handling the creation of the BMP File c Initialization of Library libusb h for the USB transfer refer to Section I C 3 d Now check if the device that is to be transferred data is connected through the proper Vendor ID and Product ID if yes then move forward else check again e Open file AVI File for the output f Set video with width height Frames per second FPS and compressor length g Clear the BMP h Call a subroutine to draw scan line on the BMP Frame 1 Call a subroutine to convert bmp to AVI frame J Clear BMP buffer variable k Check if the maximum limit of the frames to be sent is exceeded If YES then END else move to the Step h This way the process repeats F List of the components required TABLE II List of the components used SN74175 SN74125 UA 7805 Stellaris ARM Cortex M3 IHI Problems and Trade Offs A Common Issues in Optoelectronic Sensing Among the wide variety of techniques for optoelectronic touch sensing most of them suffer from a few common problems which can interfere witha system s success due to the improper working of the ambient light sensitivity 1s perhaps the most important noise factor in optoelectronic multi touch systems followed by active light interference B Clocking of the hardware and bit rate of data acquisition The clocking of the hardware Cs and ot
6. and telecommunication engineering for guiding us and reviewing our paper AUTHORS 1 Vasuki soni Student B Tech Bachelor of Technology Dept of Electronics and Telecommunication Engineering National Institute of technology Raipur Raipur Chhattisgarh India E mail vasukisoni gmail com 2 Mordhwaj patel Student B Tech Bachelor of Technology Dept of Electronics and Telecommunication Engineering National Institute of technology Raipur Raipur Chhattisgarh India E mail moradhwajpatel gmail com 3 Rounak singh narde F Student B Tech Bachelor of Technology _ Dept of Electronics and Telecommunication _ Engineering National Institute of technology Raipur _ Raipur Chhattisgarh India E mail rounaksingh17 gmail com International Journal of Scientific and Research Publications ISSN 2250 3153 Volume 3 Issue 3 March 2013
7. bmp files to AVI Video Figure 7 RED Spot shows the IR LED and the Black semicircles denote the IR Receivers Figure 7 Finger touch on the panel obstructing the path of IR rays for one IR LED 6 Creating Video interface with CCV Community Core Vision Up to this stage we have a video which now is capable of showing where actually the touch was detected 1 e Blob with respect to the Sensor Matrix Frame This information at this stage is now very useful as these videos are ready to be interfaced and fed to the Image Processing software CCV Community Core Vision this software takes the video input stream made by the frames of blob detection images as in Section II C 4 from touch panel and outputs the tracking data which is useful for mouse movements So we now have the video being interfaced with the software and now required is a software driver which can synchronize the blob position figured out by CCV with the mouse movements 7 TUIO Mouse Driver Implementation TUIO is an open framework and platform to support the tangible user interface The TUIO allows the transmission of meaningful information extracted from the tangible interfaces including touch events and object specifications This protocol enciphers the control data from a tracker application e g based on computer vision and sends it to any client algorithm that deciphers this information This combination of TUIO trackers pro
8. the Sensing circuitry These sensors are connected along a line to form the two opposite sides of a rectangle just like that of a Laptop or a computer screen These sensors are built in the form of modules which contain 8 sensors and an IR LEDs These LEDs are actuated not all at a time but one by one TABLE 1 Infrared LED and Receiver Infrared RX TSOP 1738 Infrared TX IR 908 Everlight 2 Sensor data acquisition The touch detection system works on the principle that finger placed in the touch panel obstruct the path of the IR Rays emitted from the periphery of the panel Due to this the receivers change in their outputs after the reception of reflected IR Rays The IR Sensors are basically actuated by the 38 KHz Modulated signal to stand out of the noise At a time only single IR LED is activated using the combination of D Flip Flop and Tristate buffer which provides accurate clock and synchronized switching of LEDs When the touch event takes place on the panel obstructing the path of the IR LED some sensors do not receive the IR Rays emitted from the LED due to the obstruction caused as above So we get a type of image as shown below in Figure 7 Now after data retrieval is our next concern Now we are having 96 sensors and 12 IR LEDs But for the data retrieval from sensors we don t have sufficient I O pins in the Stellaris ARM Cortex M3 microcontroller Hence we are using the Shift Registers SN74165 to increase the I O p
9. whole assembly Power consumption reduction Reducing the processing delay Good frame rate Se ee A Technical Background This implementation is an inspiration from the series of technologies presented in the near past Microsoft introduced Microsoft Surface which uses the Infrared camera to sense the Blob Touch Points Another one was presented by Microsoft which was used in the Thin Sight A Multi Touch technology in which the developers have made the touch sense panel using the Infrared Sensors lying all over the surface of the Touch Sensitive Plane to achieve Multi Touch Feature We hereby use the idea and bring a change in the former idea by reducing the number of sensors used by using the sensors only along the periphery of the surface and not covering the whole surface Many more like Microsoft Pixel Sense and the Touch User Interface made by NUI Group using CCV Community Core Vision software These inventions and technologies had their efficient contribution towards the recognition of the touch technologies in the modern world B Prior Art 1 Microsoft Surface 1 0 It 1s a 30 inch 76cm 4 3 rear projection display with integrated PC and five near infrared cameras that can see fingers and objects placed on the display from below The cameras vision capabilities enable the product to see a near IR image of what is placed on the screen the image is then captured at approximately 60 Frames per second FPS
10. E A E E A E AAA Hin VV vec RI We IR_LED GND IR_LED GND IR LED GND R LED GND IR_LED GND IR LED GND vec R1 VCC R1 vec R1 vec RI vec RI Vcc R1 We We w el W we IR_LED GND IR LED GND IR_LED GND R LED GND IR_LED GND IR_LED GND P MBASAN AU TU TU ITI e o A O N e E Figure 11 Touch Panel NOTE The touch panel shown does not show the details of connections rather is just helpful in getting an idea of how actually the touch panel looks and the arrangement of sensors LEDs with respect to the screen International Journal of Scientific and Research Publications ISSN 2250 3153 Volume 3 Issue 3 March 2013 E Software The software foundation and flow of system processing is organized in way as given in the below flow chart Figure 12 Furnishing the Infrared LEDs with 38KHz modulated signal with the D Flip Flop and Tristate buffer Extraction of data from Sensor array using Shift Register Synchronous Serial Interface for receiving data coming from Shift Registers and providing clock to shift registers USB based transfer Bulk Transfer Creating scan lines using the sensor data and then an image frame Creating Video from the image frames obtained from the sensors Configuring CCV and TUIO driver for the Mouse control Figure 12 Flow chart for software implementation 1 Brief steps for the system implementation a Initialization of the memory and the initial status for the IR LED and IR Sensor data b
11. International Journal of Scientific and Research Publications ISSN 2250 3153 Volume 3 Issue 3 March 2013 An Interactive Infrared Sensor Based Multi Touch Panel Vasuki Soni Mordhwaj Patel Rounak Singh Narde Department of Electronics and Telecommunication Engineering National Institute of technology Raipur Raipur Chhattisgarh Abstract This paper contextualizes an idea of implementing an Interactive touch sensitive user interface It is an optical touch sensing technique and architecture that allows precision sensing of hands fingers and other objects within a constrained 2 dimensional plane This paper gives the details of the touch panel a hardware and software based architecture for multi touch sensing This is a flat panel optical multi touch scheme using a linear array of modulated light receivers which surround the periphery of a display to detect touch It is a point to point visual hull sensing technology meaning it uses much of modulated infrared sensors and many IR LEDs 4 940nm to create a series of invisible light beams that cross the screen When these beams are being interrupted it means something has touched the screen and we can visualize interruption of the beams to reconstruct the visual hull of any objects inside the sensor frame This way the touch interrupt occurred is first transformed into an image with several scan lines and then many such images make a video clip which contains the information of the to
12. Section II 1 2 that the IR Led requires a modulated signal for the its proper working Previously we planned to use NE 555 timer for the timing pulse generation but the circuitry could have been more bulky unnecessarily So it was a better option to use timer of the Microcontroller supplied through a combination of D Flip Flop and Buffer to provide a pulse of required frequency 1 e 38KHz to the IR LEDs as it avoids the problems regarding the voltage fluctuation also and reduces the hardware connection as unlike 555 timer it does not require extra connections to furnish a timing circuitry This signal is going to be received by TSOP 1738 An IR Sensor which detects signals modulated with some schemes like RC5 NRZ Manchester coding with 38 KHz frequency Thus this unique detection technique makes the selection of the Sensors and LED quite profitable and brought us good results in terms of sensitivity SERIAL INPUT SHIFT REGISTER OUTPUT TO SYNCHRONOUS SERIAL INTERFACE A 1 iH aa TSOP IR Sensor Array SHIFT LOAD SIGNAL FROM GPIO INHIBIT CLOCK INPUT Figure 8 Infrared sensor array The processing unit constituted by Stellaris ARM Cortex M3 is a high speed controller that operates at appreciably high speed of 80MHz with 100 DMIPS which is too good for the performance of our system because we have to handle the making of image from the sensor data
13. ate modify and write BMP image files This image is actually made by creating scan lines 1 e line between a receiver and transmitter made when the communication between them is successful and these scan lines are made in the image for each possible Rx Tx pair in the sensor matrix A sample image made during our implementation using dummy data in which every possible Rx Tx pair is communicating successfully as no touch obstruction is present is Shown below in Figure 6 Figure 6 Scan Lines created when no finger was placed with all LEDs ON 5 Creating AVI Audio video interleave Video file from the frames Images of scan lines obtained We are now ready with the sensor data and frames of images obtained in Section IIJ A 4 Now we are ready to make a video AVI Video by using the frames Now in case of a Touch sense on the touch panel for each LED there is generated one image as in Figure 7 and the required frame is the one obtained by the sensor data refer Section III A 4 corresponding to all LEDs actuated because actuation of each LED will create a frame but the final image is that which is obtained after overlapping all the frames obtained corresponding to each LED lit which will contain a Touch Point visible and all other space is and many such final images are required to make a Video file This algorithm is implemented using bmp h and avi h header files and is written for the purpose of converting
14. buffer with tri state output http www ti com it ds symlink sn74ls 125a pdf 8 SN74165 Parallel load 8 bit shift registers http www ti com lit ds symlink sn74165 pdf 9 SN74175 Hex quadruple D type flip flops with clear http www ti com lit ds symlink sn74 175 pdf 10 AVR410 RCS IR Remote Control Receiver Product Vendors 11 Texas Instruments hittp www ti com 12 All sensors http www allsensor in Websites and Documents 13 SSI Synchronous serial interface http en wikipedia org wiki Synchronous_Serial_Interface 14 USB Universal serial bus Wikipedia http en wikipedia org wiki Universal_Serial_Bus 15 Community Core Vision CCV NUI Group http ccv nuigroup com 16 GIT Hub hittp www github com 17 TUIO http www tuio org 18 USB Ina nutshell www beyondlogic org usbnutshell usb4 shtml 19 Microsoft Surface http www surface com 20 Seth Sandler Multi touch How to http sethsandler com multitouch 21 Microsoft Pixel Sense http www microsoft com enus pixelsense pixelsense aspx Library Header files borrowed 22 USB header file libusb h www libusb org 23 BMP Library file bmp h http zsmith co bmplib html 24 AVI Library file avilib h 25 http www networkmultimedia org current Docs D oxygen html avilib_8c html ACKNOWLEDGMENT The authors would like to thank Prof B Acharya Head of the Department Dept of Electronics
15. ce solution for computer vision and machine sensing It takes a video input and outputs tracking data e g coordinates and blob size and events e g finger down moved and released that are used in building multi touch applications This way we achieve the touch sense as well as the corresponding mouse movements B Prior Work and Learning In the previous implementations that were seen in Section I B reveal that the use of Infrared transceiver pair can be efficiently done in the domain of touch detection As in Thin Sight 2 and Microsoft Pixel Sense 21 we saw that infrared sensors were used but sensors all over below the surface of touch were quite large in number and may increase in their number further with the increasing need of the resolution So we in our design have optimized the touch sense panel and found following improvements 1 First of all we have reduced the number of sensors as we are using sensors only along the periphery of the touch panel Secondly hence also we reduce the power dissipation consumption for the whole lot of sensors and transmitters 2 Another important parameter that is the processing delay of the system is also reduced as the number IC s and driver circuitry as well as data acquisition circuitry required is also considerably reduced due to reduction of sensors Detailed timeline of the project Preparation of the Sensor panel for Touch gt F The sensor panel comprises the major part of
16. emitter As this angle increases the part of the screen that is sensible to touch also increases The Infrared emitters LEDs in our design use forward current of 20 50mA so one factor was to look at the powerful voltage and current supply for them B Functional testing During the testing and PCB design we were aware of the fact that the IR LEDs would require large current So as for the touch detection we had to switch ON the LEDs but 1f all the LEDs were ON simultaneously then a lot of current could have been drawn from the power source which would let a large power to be dissipated Hence we decided in our design to let the LEDs be switched ON one by one Hence we got rid of the problem The performance data was analyzed as follows e Resolution The touch panel gave a good level of sensing for a Laptop sized panel of 15 6 inches e Power The power in this system was found to be optimizable as the clock management feature in the Stellaris ARM Cortex M3 has the ability to switch between the high frequency clock to low frequency clock to offer sleep modes low power modes Processing delay This parameter was basically affected by the algorithm implemented and proper serial communication and synchronism The improvement of this parameter depends on the Clock management and the Bit rate for the serial communication e Frame rate This needs to be set by the user and is generally limited by the capabilities of the processing uni
17. her circuitry is point of great concern as well as the bit rate settings because these parameters need to be set properly for the peripheral interfacing If there is a mismatch or improper clock given to the hardware such as Shift Registers D Flip Flop and Buffer this will prevent the system from doing efficient data acquisition and also will lead to loss of much data due to asynchronous operation C Increasing current load and voltage drop In this design when the sensor modules were tested independently there was no problem with the outputs they gave but when all the sensors were operated simultaneously they drew such an amount of the current that it was not possible for the sensors to sense and give proper output to be detected Hence as learning we understood that a high current drive could be used according to the rating of the sensors for their proper working IV Results So after a detailed analysis and final testing of the project following test results were appearing A Performance analysis The performance of the touch prototype seemed to be sufficiently good and has a fairly good resolution also but the International Journal of Scientific and Research Publications ISSN 2250 3153 Volume 3 Issue 3 March 2013 sensitivity of touch was found slightly week at the edges of the panel formed by the sensor assembly The accuracy of the touch actually depended on the angle of dispersion of the IR Rays furnished by the IR
18. ins The data is then collected by the 8 Bit Parallel Input Serial Out PISO Shift Register This serial data coming from each shift register in each sensor module having 8 IR Sensor and 1 IR LEDs are padded serially in the bit stream which finally reaches the microcontroller and is received using the SSI Synchronous Serial interface Now the data is ready for further processing 3 USB Based Serial Communication with microcontroller Moving next our requirement is then to send the data bytes received from each module to the computer This is accomplished using the USB Based transfer This transfer is a serial transfer which is carried out using C language supported International Journal of Scientific and Research Publications ISSN 2250 3153 Volume 3 Issue 3 March 2013 by the functions in the LIBUSB H certified by GNU We are using Bulk Transfer scheme because the data in the form of an image as in Section III A 4 has to been sent over USB which is a Long Burst data for which the Bulk transfer is basically meant for So it is very useful for us in this step 4 Implementing C Language for the Image creation using the Sensor Matrix data The data retrieved in the previous step is now utilized for the Image creation which will give us the pictorial representation of where actually in the 2 D Plane of Touch panel was the touch detected This is done using the C Programming The bmp h 23 is a header file which allows us to cre
19. k and the power is switched on 2 Three Dimensional Sensing Future work may investigate 3 D Interaction By using Infrared modules in non planar configurations three dimensional visual hull sensing is possible This can be accomplished by stacking multiple planar layers or by using non planar arrangements in any configuration It has the potential to provide precision for smaller interaction areas b iL 1AN D 1 eA 2 3 Form Factors Because this touch modules can be arranged into in any number of form factors possibilities abound One interesting form factor is using two strips of sensors to create a multi touch or free air interaction There is no need to create a complete polygon of sensors as the one to many relationship between receivers and LEDs enables multi touch sensing even without enclosing the sides of the sensor APPENDIX A e PCB Design for the Sensor Module The PCB Designing has been done in CAD Software EAGLE v 6 1 This board consists of the 3 Sensor Modules assembled together each having 1 Infrared LED at the front of the board and 8 infrared sensors just behind in a linear array Each 8 sensor assembly is connected to a Shift register 8 and the LED at the front is supplied frequency of 38 KHz from the timer of Microcontroller and is supplied through a D Flip Flop PI and a Tristate Buffer The blue lines on the below PCB Layout show the copper track to be printed The Red lines denote the Jumper
20. n addition to such an incremental improvements we are also exploring new applications and interaction techniques that can truly benefit from multi touch multi user and tangible input Thus our project can be implemented better using multi touch interaction for education purposes making such activities more intuitive engaging social and fun B Completeness of the project This project 1s complete in the sense of application areas where the sensitivity and resolution are not a big issue at all like school education in villages where only the students have to be taught big letters shapes pictures and moving or controlling those using fingers But this project due to its easy structure was not built taking more resolution into consideration as the algorithm implemented to detect touch allows us to detect touch almost finely So for the purpose of the advanced application like mobile and interactive displays we need to work more on the resolution C Need for the further optimization We need to work more on the hardware like in our system we found that if the IR sensors that are TSOP 1738 were more small the resolution of the system could have been improved in terms of the touch sensitivity in a better way We can also try to extend the scope of our software implementation to eliminate the need of the software platform like CCV D Market value of the product The product needs a good packaging and needs to be slim more So the prod
21. t like the rate of the sensor data reading The size of the hardware may vary according to the size of the display 5 Conclusions A Summary The importance of this project is that we have tried to implement an easy to use portable and cheap multi touch panel This has special meaning for students who are aloof from an Interactive Education system just due to lack of handsome amount in their pockets The device is affordable by almost every village level offices and schools This is going to be profitable because its packaging and assembly doesn t allow unnecessary interference in the normal working of the touch panel This final project 1s successful with most of the objectives and goals fulfilled We believe that the prototype presented in this paper is an effective proof of concept of a new approach to multi touch sensing for thin displays We have shown that how this technique can be integrated with Optical display such as computer laptop screen The optical sensing allows potential for rich data to be captured by the display and processed using computer vision techniques This allows new type of human computer interface that exploits multi touch and tangible interaction on displays making such interaction techniques more practical and deployable in real world applications We have tried to expand the sensing area to cover the entire display which has been relatively straightforward given the scalable nature of the hardware I
22. to the importance of touch technology in relation to our project and the previous work Section II describes the problem focused in this project Section II B gives the detailed timeline of the project implementation Section H D describes the hardware implementation and Section I E on the other hand describes International Journal of Scientific and Research Publications ISSN 2250 3153 Volume 3 Issue 3 March 2013 the software implementation Section III states the problems and tradeoffs Section IV presents results of the simulation and the testing and presents an analysis on the performance characteristics of the system II PROBLEM STATEMENT A Concept This is a concept of visual interface which deals with the application of the linear array of Infrared sensors along the periphery of a panel which can be made touch sensitive We need to provide a system which can digital interface to the Stimuli In the Figure 5 below we just attempt to picturize a concept of interactive education Figure 5 Interactive education In this project we are using an algorithm to first detect the touch point and its corresponding blob using the sensor data received using a USB Interface and we are creating an image from that data using Image Processing library in C Language Now using these frames we create an AVI video file This video file is utilized by the image processing software Community Core Vision CCV from NUI Group An open sour
23. tocol and client implementations allow the rapid development of tangible multi touch interfaces Finally we are now at a stage to successfully run our Touch user interface having mouse moves well synchronized with the Finger movements and gesture D Hardware I Overview The hardware of the project can be broadly classified into two major blocks as stated in the previous sections One is the Data acquisition circuitry the other one is the processing and the third one is the User Interface unit The Data acquisition block can be further sub divided into Sensors for sensing the touch interrupt and the Shift Registers for receiving data from sensors The communication part is handled under USB International Journal of Scientific and Research Publications ISSN 2250 3153 Volume 3 Issue 3 March 2013 protocol The rest part constitutes the User Interface 1 e the multi touch panel which directly interacts with the User The following Section II C 2 will give us a better understanding of the system design 2 System design and Hardware requisites The system assembly involves a lot of hardware and their interconnections The IR LED used in our project is IR 908 High Intensity Diode with 60 radiance angle because we know that IR rays emitted in the touch panel should cover maximum angle so as to cover as many sensors as possible to make the touch detection more sensitive and accurate hence increasing resolution We have seen in the
24. uch point Blob which is then interfaced with the Image processing software for the Blob detection and Mouse cursor control H Keywords CCV Community Core vision R Infrared FPS Frames per second LCD Liquid crystal display AVI Audio video interface USB Universal serial interface ARM Advanced RISC Machines TUIO Tangible user interface NUI Natural User Interface I INTRODUCTION AND MOTIVATION This technology presents an idea that is basically dedicated to the field of Education In our day to day life we see that in the field of education it involves more user interaction for better understanding In the village areas and in many schools colleges this has been the requirement that the education needs to be more interactive But simply due to the lack of resources it 1s not yet been possible for us to provide such a solution which is affordable at the Village Level So the touch technologies now come up to show innovation in the same This application provides a visual touch sensitive interface to the Computer operated device by which user without touching the mouse can easily operate it Just imagine a person moving and zooming images on a screen not by mouse but by his fingers All this is possible after having implemented the interface explained as above The main goals of this project were to do the following improvements Ease of handling and affordability at village level Reducing the size of the
25. uct at this level is sufficient in the design point of view and satisfies basic need of a Human computer interaction HCI but needs more modeling to hold a good position in the market E Feasibility The Touch panel is very easy to use and handy because it is nothing but just a flat panel builds around an array of sensor This just needs to be fit on the front of surface we intend to International Journal of Scientific and Research Publications ISSN 2250 3153 Volume 3 Issue 3 March 2013 make touch sensitive like a Computer monitor screen Low cost of installation and less human interference makes it more user friendly and easy to use Hence we can expect a good future of such implementation for the domain of Interactive Education which is our main point of concern One can think that in the bulk production of such modules the project cost can be further minimized Hence it is a profitable adaptive affordable and most primarily a feasible solution for the purpose of the Interactive Education as stated in this paper F Future work 1 Sleep modes These are the modes of the activity to control the power consumption These include the switching off the main clock and running the system on low frequency clocks in case of the system being left on hold system is in unused state for a sufficient time As soon as the touch interrupt is detected the clock management automatically gets transferred to the main clock High frequency cloc
26. ust behind any LCD display so as anyone places its finger over the LCD screen the light is reflected back and the position of the touch is then transferred to the image processing software for the optical touch based control Figure 3 below shows the implementation of the Thin Sight Borrowed from Microsoft Research Figure 3 Thin Sight technology Surface of touch filled completely with the sensors and above it are the detected blob touch points 4 Microsoft Pixel Sense It allows a display to recognize fingers objects and hands placed on the screen enabling vision based interaction without the use of cameras The individual pixels in the display see what s touching the screen and that information is immediately processed and interpreted Protection glasses p LCD Glass Panel with IR Sensors Optical Sheet Backlight with visible and IR LED Embedded PC Housing Pixel Sense Panel Figure 4 Microsoft Pixel Sense But as it is easy to understand from the details of the implementations above that either Infrared sensors used were in bulk or Cameras were implemented So we have optimized the design by working over the parameters such as reducing the number of sensors size of overall hardware Processing Delay Frame Rate Power dissipation Ease of handling etc C Organization of the report This paper is organized in the way as explained further Section I is the fundamental introduction
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