Stability Analysis and Experimental Validation of Standard Proportional-Integral-Derivative Control in Bilateral Teleoperators with Time-Varying Delays

Abstract

The control of bilateral teleoperation systems with time-varying delays is a challenging problem that is frequently addressed with advanced control techniques. Widely known controllers, like Proportional-Derivative (PD) and Proportional-Integral-Derivative (PID), are seldom employed independently and are typically combined with other approaches, or at least with gravity compensation. This work aims to address a gap in the analysis of bilateral systems by demonstrating that the standard PID control law alone can achieve regulation in these systems when a human operator moves any of the robots while exchanging delayed positions. Experimental results are consistent with the theoretical analysis. Additionally, to illustrate the high degree of robustness of the standard PID, further experiments are conducted in constrained motion, both with and without force feedback.