A Position-Based Impedance Control Strategy of Bilateral Teleoperation System with Force Feedback

A novel position-based impedance control strategy is developed for trajectory tracking and force feedback of a bilateral teleoperation system in contact with the environment. The control scheme consists of the inner loop PD control and the outer loop impedance model. During the process of trajectory tracking, the interaction force between the slave manipulator and the environment is converted into a position correction through the impedance model, which works as the motion instructions of the slave robot together with the reference position of the master device. Meanwhile, the operator can adjust the movement of the master device based on the feedback interaction force, which helps the operator to optimize the trajectory of the salve robot and the interaction force correspondingly. The Lyapunov function is employed to prove the tracking performance and global stability of the teleoperation system. Experiments are carried out on a Novint Falcon master manipulator and a seven degrees of freedom(DOFs) robot. The results demonstrate the validity and effectiveness of the proposed control method.