Nonlinear adaptive control for dynamic and dead-zone uncertainties in robotic systems

Accurate position tracking performance of robotic systems with both dynamic and dead-zone uncertainties is difficult to achieve by traditional adaptive control. In this paper, for nonlinear robotic systems in the presence of uncertain dynamics and dead-zone, an adaptive control scheme is employed to guarantee accurate and stable position tracking. The dynamics of the robot and dead-zone parameters are concurrently estimated in the adaptation laws and the estimated values are subsequently applied in the control law. In order to demonstrate the practicability of this paper, an experimental setup composed of Phantom Omni robots are built. The experimental results show that even when the dynamic and dead-zone uncertainties simultaneously appear, the robot can well track any desired position trajectory.