Combined vision/force control at corners in planar robotic contour following

The accuracy and execution speed of a force controlled contour following task is limited if the shape of the workpiece is unknown. This is even more true when the workpiece contour contains corners. This paper shows how a combined vision/force control approach at corners in planar contour following results in a more accurate and faster executed task. The vision system is used to measure on-line the contour and to watch out for corners. The edge is correctly located by incorporating the compliance of the tool/camera set-up in the contour measurement. A simple corner detection algorithm is presented. Once a corner is detected, the finite state controller is activated to take the corner in the best conditions. Experimental results are presented to validate the approach.