Model-Free Robust Joint Control of Flexible Joint Robots

In this paper, an uncertainty and disturbance estimator(UDE) based joint torque robust control method is proposed for robot with flexible joint. The conventional approaches to controlling flexible manipulators mostly focus on the motor side of the joint since it is much stiffer than that of the link side. However, this method reduces the position accuracy of the joint. Here we propose a model-free UDE-based robust torque control method on the joint link side. This method can estimate system disturbances and uncertainties, requiring only knowledge of the system's bandwidth. The numerical simulation results show that the proposed robust controller in this paper can achieve higher positional accuracy.