An Approach for Peg-in-Hole Assembling Based on Force Feedback Control

In this paper, an intuitive and effective method is proposed for a sensor guided industrial robot to carry out the Peg-in-Hole assembly. This method contains two main steps. The first step is calibrating the wrist force sensor to compensate the load gravity and the bias of sensor so that the external force on the load can be precisely obtained. Secondly an impedance controller is designed to realize the compliant behavior between the manipulator and external environment. Different from the traditional method based on the position control loop, the force control strategy is based on the robot end-effector velocity control loop, which is easier and convenient to implement. Finally, a Peg-in-Hole experiment using an industrial manipulator with wrist sensor and a Peg-in-Hole mould with a tiny clearance was successfully completed. The experimental results verified the effectiveness and practicability of the proposed method.