Robust control of smart material-based actuators

Abstract

Actuators incorporating smart materials are competitive choices for micro-positioning devices, but they are difficult to control because of their nonlinearity and hysteresis. These actuators are shown to be passive using several different approaches. Using passivity, a class of stabilizing controllers is identified. A controller for velocity control is designed that optimizes tracking performance and evaluated experimentally. A different approach is used to establish stability and tracking when position control is required. Robust stability is obtained in both approaches since stability is not sensitive to actuator parameters. © 2008 Springer London.