Adaptive control of robotic manipulators including motor dynamics

Motor dynamics in a mechanical transmission chain of a robot are common in practice and may significantly affect the dynamic characteristics and stability of a robot. Synthesis of a robust controller for a robot, including motor dynamics, is essentially more complex than that for rigid-body manipulators. The controllers currently in existence require exact knowledge of both the robot and motor dynamics. The acceleration feedback is needed to form a complete state feedback vector for the third-order dynamic system. In this paper, an adaptive controller is proposed, which is able to deal with uncertainties in both the robot and the motor dynamics. An adaptive nonlinear observer is designed to observe the acceleration instead of measuring it by feedback. The closed-loop system is proved to be globally stable in the Lyapunov sense