automaticle clamping

The task: create a clamp whose clamp synthetic plate from 10mm to 20mm thickness. The Position must be arrived automatically. You need this clamp on a Drilling machine, which cross the clamp by production. If the cutter is coming, the ultrasonic sensor open and Close the clamp, so you don`t have a crash. All clamps, will be controlled, from a simple SPS-controlling-System.