Multitouch Mini (MTmini) – How To

What’s a Multitouch Mini (MTmini)?

A Multitouch Mini, MTmini for short, is a cheap, small, portable multitouch pad. It can be used for all different purposes including: drawing, OS navigation, multitouch operation, games, entertainment, experimentation, and more. I created the Multitouch Mini to show people how something that seems complicated or ‘magical’ can be made simply and at low cost.

The MTmini uses the “Front Diffused Illumination” multitouch technique, with normal ambient light (infrared not required or needed) and a normal off-the-shelf webcam (IR filter can still be in place). The MTmini technique is the first step in creating a full multitouch display.

Parts List

• Box (ie. Cardboard, Plastic, etc)
• Piece of Clear, Flat Sturdy Material (ie. Glass, acrylic, plexiglas)
• Paper (ie. printer paper, tracing paper, almost any paper)
• Webcam (most web cameras will work)
• Computer (dual core recommended, but not required)
• Optional:
  • Picture Frame

Total Cost: $5 – $50

How’s it Work and What Conditions are Necessary?

When you place your fingers on the surface, shadows are created where your fingers are placed. The webcam sees these shadows and sends the image to the tracking software which tracks the shadows as they move on the touch surface (paper).

Below is a video demonstrating the view of what the camera is seeing and tracking.

All you need is a room with (at least) some light; a dark room will not work. Even room lighting gives the best results.  Lights shinning from multiple directions onto the multitouch pad gives better results than lights from one direction.

Software and Demo Downloads

• Main Finger Tracking Application – needed to track fingers on the MTmini
  • Community Core Vision (CCV) – Windows, Mac, Linux tracking application.

• Mouse Driver – for controlling your mouse cursor
  • Windows Mouse Driver
  • Windows 7 multitouch driver (Multitouch Vista)
  • Mac, Linux, Windows Mouse Driver from TUIO.org
• Demos and Applications – Various applications that can be used with the MTmini
  • Demo pack applications (fire, physics, ripples, multikey, and more) - via ccv.nuigroup.com downloads page
  • My Demo Applications
  • Angry Birds (seen in the video) uses one of the mouse drivers above

Tracking Software Installation and Setup Guide

• http://sethsandler.com/multitouch/community-core-vision-guide/

Want to Build a Multitouch Surface?

See the MTbiggie page to create your first multitouch table!

Need Help?

If you need more help than is provided here, please go to http://nuigroup.com/forums where there are hundreds of other people that are building multitouch devices and can answer your questions quickly.

Other Resources

• How to Make a Multitouch Surface
• Multitouch Book (free PDF)
• Multitouch Terminology
• My Personal Multitouch Surface Build
• NUIGroup (the best place for immediate help on hardware and software)

Thanks to:

• David Wallen
• Christian Moore
• Laurence Muller
• NUIgroup Community