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This paper proposes the design and validation of a novel rate-dependent direct inverse Preisach model with input iteration (RDIPMII) dedicated to feedforward compensation of hysteresis nonlinearity in piezoelectric actuators (PEAs). Unlike existing similar works, the proposed RDIPMII avoids deriving the parameters of the inverse compensator from the hysteresis model, and could be directly employed as the inverse compensator. Furthermore, RDIPMII is capable of achieving rate-dependent inverse compensation while reducing the experimental burden in identifying models by the use of newly proposed data expression method (DEM). In addition, by integrating iterative learning control (ILC), RDIPMII accomplishes online input iteration to further suppress the hysteresis effect. The feasibility and efficiency of the presented scheme are demonstrated through experimental investigations conducted on a PEA. [ABSTRACT FROM AUTHOR]

The feedforward inverse compensation is a typical approach to compensate for the hysteresis nonlinearity in smart materials based actuators, which often requires to develop a hysteresis model first and to compute the parameters of the inverse compensator based on the hysteresis model. Different from the above method, a direct inverse model (DIM) constructed by newly proposed clockwise relay operators is developed in this article. The direct inverse modeling approach is free from constructing the inverse compensator, and can be directly used as the inverse compensator. The parameters of DIM can be obtained via the model identification using the experimental data. In order to facilitate the numerical implementation and reduce the model complexity of DIM, a QR factorization based selection mechanism is employed to select the dominant clockwise relay operators. The reduced DIM is capable of preserving the accuracy of the full DIM. The simulation study and experiments are conducted to validate the effectiveness of the developed compensation approach. [ABSTRACT FROM AUTHOR]

In order to solve the hysteresis nonlinearity of piezoelectric ceramic actuators, a closed- loop control strategy base on Preisach inverse compensation is proposed in this paper. Firstly, an inverse Preisach model was achieved using the sorting & taxis realization method. And the inverse model was connected in series with the hysteresis of the system to reduce the impact of the hysteresis. Then, a PI controller was designed to attenuate the non-linearity, which could not be compensated by inverse model. Using the designed PI controller, the tracking accuracy could be improved, and the average absolute error decreased to 0. 025 µm. Experiments show that the inverse Preisach model control strategy has good control performance. [ABSTRACT FROM AUTHOR]