Calibration of closed loop controllers for setting impedances in force-reflecting systems

Jayachandran, V., Rahman, T., Salganicoff, M., Heredia, E. and Harwin, W. S. ORCID: https://orcid.org/0000-0002-3928-3381 (1997) Calibration of closed loop controllers for setting impedances in force-reflecting systems. In: ASME Dynamic Systems and Control Division Conference 1996, 17-22 Nov 1996, Atlanta, GA, USA. (Unpublished)

Abstract/Summary

This paper discusses a new method of impedance control that has been successfully implemented on the master robot of a teleoperation system. The method involves calibrating the robot to quantify the effect of adjustable controller parameters on the impedances along its different axes. The empirical equations relating end-effector impedance to the controller's feedback gains are obtained by performing system identification tests along individual axes of the robot. With these equations, online control of end-effector stiffness and damping is possible without having to monitor joint torques or solving complex algorithms. Hard contact conditions and compliant interfaces have been effectively demonstrated on a telemanipulation test-bed using appropriate combinations of stiffness and damping settings obtained by this method.