TARGET: Touch-Activated Response Gaming Entertainment Table

1. TARGET:Touch-Activated Response Gaming Entertainment Table Team Siqueira: Pat DeRoy, Cory Gorman, Marc Perras Preliminary Design Review

2. “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”

3. 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

4. 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

5. 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.

6. 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

7. Block Diagram

8. 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

9. 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) • Σ = 768,000 pixels • 4 bytes per pixel (RGBA) • => 3,072,000 bytes per frame

10. Constraint: Speed and Timing • Suppose it takes 5 cycles of processing per byte. • 5 cycle/byte * 3072000 byte/frame = 1.536*107 cycles/frame • * 30 frame/second = 4.608*108 cycles/sec. • Roughly equals 460 MHz.

11. 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

12. 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

13. 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

14. Design Concept

15. Deliverables • Implement FTIR • Projector position • Image and graphics processing • Physics engine • Multiple games • User menu • User manual • Attract mode

16. 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)

17. 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

18. Timeline 5-8. Software 3. PC prototype 10. Finishing Touches/ Expansion 1. FTIR PDR MDR CDR FPR SDP Day 4. Interface Components 9. Finished Table 2. Projector

19. 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

20. 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

21. Questions?