MultiTouch LightBox

LightBox

This proof of concept of the multi touch system not using IR technology and using the human eye viable spectrum 400nm-700mn. shadows from light(s) within the box will be capture on the 'glass surface' via the web cam. The Surface will need to use a diffuser with the correct oipacness to allow object (like fingers) to be recognized. This information will be process by a computer to do cool things. Phase 1:  Research Gather Supplies needed  Items needed    cost  comments  2 usb webcams   $10 found on woot  2 Glass/plexi       $8 got from hardware store  2 Boxes              free have them  Diffuser              free bought from hobbie lobbie  Projector             N/A don't need  IR gear             N/A don't need Phase 2  Design/Build Phase 3  Test Hardware/Software Setup web cams are installed and have been calibrated (aligned and focused) Software Calibration done (tbeta) Phase 4  Develop Software Successfully ran Photo Demo software    Phase 5  Review Improvements for next version Pros Cheap to make Simple to make Would be easy to do large scale Cons exterior shadows cause slight problems with touch recognition exterior lights need be off (lights cause shadows) not very reliable as far as accuracy or consistent results No good way to read QR codes No good way to No or very little difference between hovering and touching surface Improvement to current design Exterior lights, learned that over head lights need to be off for this to work better might be hard integrate display into the surface (using interior light as backlight, but visable light might make it hard to tell what are figers and what is the display)

Multi Touch ShadowBox

you don't know how good you kids have it...


Before the iPhone and touch screens, My friend and I saw this add for MS Surface. We loved the idea but didn't have $12,500 to buy one. However the NUI Group, was a open source project that showed how to make a multi-touch table. The 'Shadow Box' was first attempt at making a multi-touch interface.




Stage 1: ShadowBox
This proof of concept of the multi-touch system not using IR technology and using the human eye viable spectrum 400nm-700mn. Building two so Dan and Bob can play with them.


Phase 1  Research Gather Supplies needed

Items needed	cost	comments
2 usb web cams	~$10	being shipped
2 Glass/plexi	~$8	will buy
Box	free cardboard	have
Diffuser	free paper	have
Projector		don't need
IR gear		done need

Phase 2  Design/Build
Diagram 1: Shadow box design

Phase 3  Test Hardware/Software Setup
web cams is installed and have been calibrated (aligned and focused)
Software Calibration done (tbeta)

Phase 4  Develop Software
Successfully ran Photo Demo software
 
Phase 5  Review Improvements for next version
Pros

• Cheap to make
• Simple to make
• Would be easy to do large scale (maybe use sun as exterior light)

Cons

• exterior shadows cause slight problems with touch recognition
• exterior lights need for use (lights need to be positioned optimally)
• not very reliable as far as accuracy or consistent results
• No good way to read QR codes
• No good way to integrate display into the surface (using visible light)
• No or very little difference between hovering and touching surface

Improvement to current design

• Exterior lights
• learned that over head lights are better then light coming at sideways angle
• printer paper worked well, but paper was fibrous. This caused little dark spots for the web cam
• would like to use material that has consistent density (less fibrous)