Jaime Oliver uses computer vision for an extended instrument using a drum frame with a pliable black membrane.  In the video, you can see how the computer becomes sensitive to the number of fingers touching, their force and distance from the camera.  Equally as inspiring as the simplicity of the controller is his choice for sound synthesis.  Further, he demonstrates experience in sound design that is unparalleled.  I have posted one of his movies using the Silent Drum
Silent Construction 1 from Jaime Oliver on Youtube.