PHASE MONITORING FOR AUTOMATED INSPECTION, POSITIONING AND ASSEMBLY.

In phase monitored inspection, acoustic waves reflected off a master part are picked up by an array or microphones. The phase shift of the reflected wave in each microphone is compared to the subsequently measured values of a part to be inspected; differences in these phase signals can be interpreted as geometry differences between master and part. The phase monitoring technique can be used for automated assembly by attaching the sound source and microphone array to a manipulator hand; the phase signals determine the relative position between the manipulator and the object being assembled. Automated positioning uses similar phase signals to position objects in the proper orientation before further machining or assembly.