A Robust Discrete Time Adaptive Servo

Abstract

This paper deals with the robustness issues associated with the design of an adaptive control servo in the presence of linear unmodeled plant dynamics. In particular, a design methodology for trajectory following control systems is presented which guarantees the boundness of the tracking error without requiring persistent excitation of the reference input. The tracking error bound is calculated as a function of the reference trajectory, using a-priori knowledge of the step response of the plant. An application of this technique to a positioning servo with an unknown or slowly varying inertia load and high frequency unmodeled resonance modes is included.