Trajectory tracking control for robot manipulators with bounded inputs based on the singular perturbation theory
Yan Sha-sha · Control theory & applications · 2009
To meet the requirement of a bounded driving torque in the robot trajectory tracking,we propose a generalized algorithm based on the stability theory of singularly perturbed systems.A saturation function with error gain is introduced in the control law,which guarantees the absolute value of the input torque to be upper-bounded within any specified range. Besides,a better tracking performance can be achieved by properly adjusting the error gains.In the meantime,a pseudo velocity error signal for substituting the actual one is generated from a linear filter containing only the position tracking error,thus,making the whole closed-loop control free from the velocity measurement.Based on the proposed algorithm, we design a novel control law with a bounded input.Comparison of simulation results show that the proposed algorithm can strictly ensure the specified bound for the inputs to the torque controller,and gives a better tracking result than the other ones under the same parameter conditions.