Vision-Based Position/Impedance Control for Robotic Assembly Task

In robotic assembly processes, detecting target pose is indispensable for robot manipulation algorithms. Such a tedious work hinders the further application of robot manipulation algorithms to real industrial processes. In this paper, a vision-based position/impedance control framework is proposed. Therein, the objective pose is firstly obtained by a motion capture system, where a kinematic equation is solved to Figure out the target assembly pose. Next the robot arm motion is approximated by an impedance model, in this way, the position/impedance control law of the robot is derived, which drives the robot to perform a compliant assembly manipulation. Finally, a memory stick assembly experiment is conducted on a 6-DOF robot arm equipped with a motion capture system and a force-torque sensor. Experiment shows the efficiency of the vision-based position/impedance hybrid controller in terms of autonomous positioning and compliant assembly. Due to its convenience and generality, the present controller can be expected to apply to more general industrial scenarios.