Inverse-Based Local Loop Shaping and IIR-filter Design For Precision Motion Control

In motion-control problems such as vibration rejection, periodical reference tracking, and harmonic disturbance cancellation, the disturbances/references share a common characteristic of exhibiting concentrated energies at multiple bands of frequencies. In this paper, we discuss a feedback loop-shaping approach to address such a class of control problem. An integration of (inverse) system models is proposed to bring enhanced high-gain control at the required local frequency regions. We show that such servo enhancement can be effectively achieved if good model information is available at the disturbance frequencies, and that a rich class of design tools can be integrated for the controller formulation. The proposed algorithm is verified in simulation and experiments on vibration rejection in hard disk drives and an electrical power steering system in automotive vehicles.

Conference paper