Nonovershooting Control of Robotic Manipulators Driven by Series Elastic Actuators

Series elastic actuators (SEAs) have prominent advantages in safe robot control due to its compliant mechanical design. Although existing SEA-driven robots can ensure safety at the hardware level, achieving safety guarantees at the control level is still underexplored in the literature. In this work, we aim to develop a safety control method for SEA-driven manipulators with nonovershooting guarantees. Specifically, a nonovershooting control method is proposed for SEA-driven robotic manipulators. Sufficient initial conditions and gain selections are derived to achieve that the output position of the manipulator tracks an arbitrarily time-varying reference without overshoot and the tracking error asymptotically converges to zero from below. In addition, an approximately nonovershooting control method is also proposed in the presence of disturbance, which exists in both the robot and actuator dynamics. By this method, the amount of the overshoot can be made arbitrarily small by appropriately tuning gain parameters. Simulation results demonstrate the obtained results.