MTC Express Multi-touch Controller.

Tactex Controls, Inc., #3 203 Harbour Road, Victoria, British Columbia V9A 3S2, Canada; telephone (250) 480-1132; fax (250) 480-1142; electronic mail sales@tactex.com; World Wide Web www.tactex.com

The MTC Express (see Figure 1), from Canadian manufacturer Tactex Controls, is a touch pad controller with a unique multi-touch capability. Though it has other uses in a variety of applications including graphics, the device is definitely being marketed with computer music in mind.

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Specifications

Using an internal web of fiber-optic strain gauges (produced under license from the Canadian Space Agency), the MTC Express senses multiple points of pressure applied to its surface simultaneously. Each contact point sensed by the pad provides its data, consisting of x, y, and pressure values, at a sampling rate of 200 Hz.

Software support is provided for both Macintosh and Windows computers in the form of libraries, example C code, and a demo application. For the Macintosh, an external for Cycling '74's Max is also provided with an associated .help patch.

The pad generates its multi-touch data starting from a 6 x 12 grid of deformation measurements gathered by the fiber optic sensors. This data is reduced within the pad to produce a list of contact points. The raw values on the grid are available through the device's Application Programming Interface (API) as well.