LuGre model based hysteresis compensation of a piezo-actuated mechanism

Abstract

This paper presents a combined feedforward plus feedback control approach to compensate the hysteresis effect, which degrades the positioning accuracy of piezo-actuated mechanism. The LuGre friction model is extended to represent the nonlinear dynamics of the piezo-actuated positioning mechanism, and then the unknown model parameters are identified with the particle swarm optimization (PSO). Based on the developed mathematical model, the inverse LuGre model based feedforward plus feedback control is designed for the motion tracking control. Experimental results show that the LuGre model based hybrid control approach achieves a satisfactory position tracking performance. Owing to a simple structure, the proposed control approach can be implemented in other types of hysteretic systems.