Stability of Velocity Control for a Piezoelectric Stepper

This paper studies the velocity control of a large-range piezoelectrically actuated (piezo) stepper. The main contribution of this paper is to extend the Poincare-map approach for evaluating the stability of the stepper dynamics in the presence of Coulomb-friction nonlinearity, which has a jump discontinuity with velocity. Additionally, inversion of the stepper-dynamics model is used to find the piezo input for controlling the stepper velocity, and model-based predictions of the stepper velocity are evaluated using an experimental-stepper system.