TouchTable

Notes on construction of a internal reflection infrared rear projection touch table.

Projection/Touch Surface

Top view schematic of the edge for measurement

Edge view schematic of the edge for measurement

Start off with a 4:3 aspect ratio so we can use a regular XVGA projector (1028x768).

A small table would have a projection area of 32" x 24"

A larger table would have a projection area of 48" x 36".

A long informative thread on the use of silicone coated vellum as a touch-compliant surface.

Table Frame Design

Could use a drafting table.

This drafting table would look neat as a touch table!

Multi-Touch Software

Touche Cocoa Framework

"Touché is a free, open-source tracking environment for optical multitouch tables. It has been written for MacOS X Leopard and uses many of its core technologies, such as QuickTime, Core Animation, Core Image and the Accelerate framework, but also high-quality open-source libraries such as libdc1394 and OpenCV, in order to achieve good tracking performance." Licensed under LGPLv3.

MultiTouch.Framework

"MultiTouch.framework is a native Cocoa multi-touch framework for Mac OS X. It uses the default event handling system and the responder chain of the operating system, providing a familiar application programming interface to Mac OS X developers. It is built upon a modular low-level architecture that unifies all touch events, with input units for different multi-touch input devices including FTIR, DI, iPhone/iPod touch, as well as any TUIO-based devices. Thus, as a developer, you do not need to care about the actual input device being used. One of the great advantages of this toolkit is that you can develop and test your multi-touch application on your standard desktop Mac, using your iPhone as multi-touch input device, without having to work at an FTIR table all the time."

There is a video at: http://youtube.com/watch?v=skZCBvWVu8A