An asymptotic torque estimation for robot manipulators

This paper is an attempt to study torque estimation problem of robot manipulators. Introducing bounded nonlinear functions to model torque dynamics, estimation of the robots states via a Lunenburg estimator is investigated. As compared with existing approaches in the literature, the main contribution of this paper is to guarantee the asymptotic stability of the estimator while the torque dynamics is unknown. Simulation results for a tele-rehabilitation robotic system evaluate the performance of the proposed torque estimation approach.