Generic Algorithm for Peg-In-Hole Assembly Tasks for Pin Alignments with Impedance Controlled Robots

In this paper, a generic algorithm for peg-in-hole assembly tasks is suggested. It is applied in the project GINKO were the aim is to connect electric vehicles with charging stations automatically. This paper explains an algorithm applicable for peg-in-hole tasks by means of Cartesian impedance controlled robots. The plugging task is a specialized peg-in-hole task for which 7 pins have to be aligned simultaneously and the peg and the hole have asymmetric shapes. In addition significant forces are required for complete insertion. The initial position is inaccurately estimated by a vision system. Hence, there are translational and rotational uncertainties between the plug, carried by the robot and the socket, situated on the E-car. To compensate these errors three different steps of Cartesian impedance control are performed. To verify our approach we evaluated the algorithm from many different start positions.