RENCI Vis Group Multi-Touch Blog

Developing multitouch hardware and applications for research and experimentation.

Entries Comments


Duke Multi-touch Wall Development - Hardware Part 1

15 September, 2008 (11:00) | Duke Multi-Touch Wall

Duke Multitouch Wall. (Photo credit: Josh Coyle)

Dr. Xunlei Wu using the Duke Multi-Touch Wall. (Photo credit: Josh Coyle)

RENCI‚Äôs initial foray into this area of research has taken the form of the 13.5-foot wide x 5-foot tall multi-touch visualization wall that was installed at the RENCI Duke Engagement Center in the beginning of May 2008. The wall sits at the end of the Engagement Center’s primary collaboration space:

Floorplan for the RENCI Duke Engagement Center showing the location for the Multitouch Wall.

Floorplan for the RENCI Duke Engagement Center showing the location for the Multi-Touch Wall.

The Wall is positioned at the end of the primary collaboration space. (Photo credit: Josh Coyle)

The Wall is positioned at the end of the primary collaboration space. (Photo credit: Josh Coyle)

This 6-projector (2 tall x 3 wide) rear projection display provides over 12 million pixels of resolution and uses direct illumination (DI) with 8 infrared cameras to track touches across its coated acrylic screen. A RENCI-modified version of TouchLib and a custom gesture library will allow users to interact with large high-resolution images for medical and disaster response applications.

Resolution Statistics

  • Visual Resolution: 6 HD projectors ~= 12.4M pixels across 13.5-foot x 5-foot span
    ~= 1330 rendering pixels/sq inch
  • Touch Resolution: 8 VGA cameras ~= 2.46M pixels across 13.5-foot x 5-foot span
    ~= 262 touch pixels/sq inch
  • Approx. 5 visible pixels per touch pixel

The Build

The physical setup was developed and designed using SolidWorks and constructed using 80/20 framing, which allowed us to adjust the component positions.

SolidWorks model of Duke Multitouch Wall.

SolidWorks model of Duke Multi-Touch Wall.

Setting the size of the screen… By laying out the modeled projector frustrums, we could see where the cameras and illuminators could exist without throwing shadows.

Projector frustrums were modeled to set the size for the screen.

Projector frustrums were modeled to set the size for the screen.

See Hardware Part 2 for more…

« Introduction to Multi-Touch

 Duke Multi-Touch Wall Development - Hardware Part 2 »

Write a comment