To compensate the hysteresis nonlinearity of a piezoelectric biomorph actuator, a new model with hyperbola functions was proposed to describe the Preisach type hysteresis nonlinearity, and an inverse controller was designed with the proposed model. Two hyperbola functions were used to fit the curves of hysteresis major loop and then the first-order ascending and descending branches were described by the coordinate conversion. Based on the wiping-out and congruency property of Preisach model, the minor loops were modeled by the corresponding first-order curves. As the parameters of the proposed model are much less than those of classic hysteresis models, such as Preisach model, the proposed model is suitable for the smart material systems including piezoelectric actuators. Experimental results show that the inverse controller designed with the proposed model can compensate the hysteresis of piezoelectric biomorph actuator, and the maximum control error with inverse controller has reduced by 44.26%.
