Torque and impedance control is at the heart of modern articulated robots such as manipulators and legged robots. This is often realized using series-elastic actuators, which utilize drivetrain compliance to provide both physical robustness against impacts and a means to measure and control outgoing torque.
Actuators in articulated robots deal with varying operating conditions, particularly changes in load inertia due to changes in the robot's configuration. Disturbance observer (DOB) based torque control provides a means to achieve robustly stable torque control in such situations.
Recently a method to synthesize robust DOB-based torque controllers for series-elastic actuators under varying loads was developed. This MSc thesis assignment focuses on further analysis of the robustness and performance of this method, specifically, reducing its over-conservatism.