An Operational Space Observer-Controller for Trajectory Tracking

Abstract

This paper presents an operational space observer-controller for non-redundant robot manipulators to achieve trajectory tracking. The controller uses an observed integrator backstepping procedure for operational space trajectory tracking control without actual velocity measurements, and the overall observer-controller system achieves a semi-global exponential stability (SGES) result for the position and orientation tracking errors, velocity tracking errors as well as velocity observation errors. Simulations results indicate that, compared with the conventional computed-torque PD control using backwards difference approach to estimate velocities, the proposed controller has better position tracking performance under parametric uncertainty and payload variations. 1.