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ECE SDP11 Team Siqueira: Pat DeRoy, Cory Gorman, Marc Perras TARGET: Touch-Activated Response Gaming Entertainment Table Preliminary Design Review Slide 2 2 ECE SDP11 All-in-One Games Table Many different pieces Often heavy Inconvenient Difficult to switch between games Can cost as much as $1000 Solution: Engineering! Make a digital games table Just push a button Slide 3 3 ECE SDP11 What does such a system need to do? Must stay within $500 budget Must be able to handle inputs from multiple users simultaneously Must be able to accurately simulate a real game with correct physics and timing Slide 4 4 ECE SDP11 Multi-Touch Surface Large screen connected to a computer Responds to user touch as input Can handle many users at once Suits our needs very well! Microsoft Surface: $12,500 Slide 5 5 ECE SDP11 Building a Multi-Touch System Input: User Touch. Picked up by IR camera, sends image of finger blobs to main system. System processes blobs to find touch locations and interprets as tapping, dragging, etc. Output: After reacting to the input, the system outputs the screen image to a projector. The projector displays the image on the surface of the table from below. Slide 6 6 ECE SDP11 Frustrated Total Internal Reflection Shine infrared LEDs into acrylic plastic along the perimeter. Arrange LEDs so that they engage in total internal reflection within the acrylic. When finger is placed on the acrylic, the total internal reflection is disrupted, due to the fact that a finger has a higher refractive index than air Infrared light escapes, and an infrared camera placed below the acrylic surface will see this escaped light Slide 7 7 ECE SDP11 Block Diagram Slide 8 8 ECE SDP11 Image Processing From camera image, find finger blobs Get the X, Y locations of the blobs Compare to previous locations to determine which have been moved, which are new touches, etc. Determine how to react to this input Slide 9 9 ECE SDP11 Constraint: Speed and Timing Some estimates: Camera resolution: 320x240 = 76800 pixels Projector resolution: 640x480 = 307200 pixels Ideally, would run at more than 30 frames/second. Tasks for each frame: Find finger locations (76800) Interpret locations (76800) Update game state (307200) Output image (307200) = 768,000 pixels 4 bytes per pixel (RGBA) => 3,072,000 bytes per frame Slide 10 10 ECE SDP11 Constraint: Speed and Timing Suppose it takes 5 cycles of processing per byte. 5 cycle/byte * 3072000 byte/frame = 1.536*10 7 cycles/frame * 30 frame/second = 4.608*10 8 cycles/sec. Roughly equals 460 MHz. Slide 11 11 ECE SDP11 Other Constraints Size: The size of the surface is limited by the throw distance of the projector and the thickness of the acrylic. Too-thin acrylic will bend in the middle Brightness: The table must be able to be viewed easily in regular office lighting. 1000 lumens projector? Budget Slide 12 12 ECE SDP11 Estimated Budget System: provided by Intel through Prof. Wolf PS3 Camera: $40 Mirror(s): $10-$20 IR LEDs: ~150 @ $0.20 = $30 Casters: 4 @ $5 = $20 Vellum: free Fans:free Wood: free Acrylic: free Projector: free Tentative Total: $110 Slide 13 13 ECE SDP11 Design Alternatives Board vs. PC Choice of Board Other forms of multi-touch that are not FTIR- based Diffused Illumination Laser Light Plane (LLP) Projector Buy one or build our own? Mirrors vs. lens system to achieve short throw distance Size of the table Slide 14 14 ECE SDP11 Design Concept Slide 15 15 ECE SDP11 Deliverables Implement FTIR Projector position Image and graphics processing Physics engine Multiple games User menu User manual Attract mode Slide 16 16 ECE SDP11 Timeline 1. Have working FTIR effect. (End of October) Frame for acrylic panel with infrared LEDs. When touched, blob visible on camera. 2. For MDR: Determine position of projector and mirrors. (End of November) Build a temporary table with variable height to try different orientations. 3. Get basic system working using a PC. (End of semester) Slide 17 17 ECE SDP11 Timeline 4. Successfully interface board with camera and projector. (End of February) Image Processing completed. Draw circles around touches. Software: (End of March) 5. Create control menus. 6. Create physics engine. 7. Create game applications. 8. Create game selection menus. 9. Finish table, including cooling system. (End of March) 10. Possible Expansion and Finishing Touches Slide 18 18 ECE SDP11 Timeline PDR MDR CDR FPR SDP Day 1. FTIR 2. Projector 3. PC prototype 4. Interface Components 5-8. Software 9. Finished Table 10. Finishing Touches/ Expansion Slide 19 19 ECE SDP11 Team Roles FTIR Panel: Solder LEDs: Assembly line Build frame: Pat Polish acrylic: Marc Wire LEDs: Cory Prepare vellum with silicon: Cory Projector setup: Experiment with projector/throw distances: Marc Placement/modification of mirrors: Marc Layout of components: Pat Build temporary casing for prototype: Pat Website: Cory Slide 20 20 ECE SDP11 Conclusion Our project is good for SDP: Expandable: with more time, can add more games and features Good amount of both hardware and software Demo-able: easy to show off and explain at SDP Day Our project is a good product: Markets: Home/Personal use, or sell to bars/arcades with addition of coin-op unit Could expand to other applications besides just games Relatively inexpensive Slide 21 21 ECE SDP11 Questions?