Abstract: A pinch detector for a movable panel is provided having a deformable and resilient channel; a sonic wave transmitter at one end of the channel having a predetermined output; a sonic wave receiver at a second end of the channel; and a controller connected to the transmitter and receiver; wherein the controller selectively activates the transmitter and generates a command in response to a predetermined attenuation of sonic wave input from the sonic wave receiver. The predetermined output of the sonic wave transmitter is in the range of about 30 to 50 kHz at a range of about 3 to 24 volts, but is preferably about 40 kHz at about 5 volts. The deformable and resilient channel can be disposed within a sealing element of a movable panel. Optionally, the sonic wave can be modulated. Compositions for the sonic tube can include latex, rubber, EPDM, foam, combinations thereof, and the like.