Monitoring the generic assembly operation for impact from gripping to finished insertion

This paper discusses how accelerometers and force/torque (F/T) sensors may be used to detect errors during assembly. The main surveillance feature is impact-expected and unexpected-registered with the accelerometers. During the actual insertion an F/T-sensor is used as support. Also a device for electric contact indication is used. First the generic assembly operation is presented and then the possible modeled error states are introduced. Finally, experiments with defective workpieces and positioning errors are presented. The experiments are done in two dimensions in an authentic assembly work cell. The aim of the paper is to show the possibilities of supervision of assembly operations by detecting and analyzing impacts