Multi-Touch Table

FrontPageSlider, Portfolio•on May 26th, 2009•

This Laser Light Plane MT Table was developed as a part of my research with the Music Engineering Technology group at the University of Miami. The system leverages commercial, off-the-shelf technologies to make a robust multi-touch table interface and software development environment. For our inexpensive implementation, we used a technique called Laser Light Plane Illumination (LLP). A laser plane approximately one millimeter thick is created over a clear surface by surrounding the table with infrared lasers diffused by line generators. The infrared nature of the lasers ensures that this plane is not within the human visible spectrum,making it “invisible.” Fortunately, computer cameras do not have this limitation. When a finger breaks the plane over the clear surface, the infrared light is deflected down into a camera. This camera is fitted with a bandpass filter that renders the visible spectrum in such a way that is is sensitive exclusively to the wavelength of the infrared light. This deflected laser light is then interpreted by computer vision software as a touch. This has yielded a platform for which we can write applications for a number of audio research tasks, as well as applications for other disciplines and research problems. Current applications of the platform include interactive/generative music synthesis, a multi-touch pong game, gesture driven music composition, an audio mixing suite, and a musical-tactile rehabilitation program for subjects with Parkinson’s disease.

We present a system that leverages commercial, off-the-shelf technologies to make a robust multi-touch table interface and software development environment. For our inexpensive implementation, we used a technique called Laser Light Plane Illumination (LLP). A laser plane approximately one millimeter thick is created over a clear surface by surrounding the table with infrared lasers diffused by line generators. The infrared nature of the lasers ensures that this plane is not within the human visible spectrum,making it “invisible.” Fortunately, computer cameras do not have this limitation. When a finger breaks the plane over the clear surface, the infrared light is deflected down into a camera. This camera is fitted with a bandpass filter that renders the visible spectrum in such a way that is is sensitive exclusively to the wavelength of the infrared light. This deflected laser light is then interpreted by computer vision software as a touch. This has yielded a platform for which we can write applications for a number of audio research tasks, as well as applications for other disciplines and research problems. Current applications of the platform include interactive/generative music synthesis, a multi-touch pong game, gesture driven music composition, an audio mixing suite, and a musical-tactile rehabilitation program for subjects with Parkinson’s disease.