Modeling and compensation of symmetric hysteresis in piezoceramic actuators

Based on the well-known Madelung's rules, a modeling method for the symmetric hysteresis description and compensation of piezoceramic actuators is proposed. The concept of turning point (TP) is introduced in the presented method. A turning point is a point on the hysteretic trajectory where the input signal changes its direction. As the recorders of the movement history, all turning points are identified and recorded. It is found that the trajectory at any time instant should be on the curve determined by a certain turning point, which is named as the current turning point (CTP). To determine the CTP, the binary search method is used locate the position of the CTP in the array of turning points, and then the trajectory can be described. Furthermore, the turning points after the CTP are wiped out to save memory resources. The benefit of the proposed method lies in the fact that it can be used to compensate the hysteresis nonlinearity with minor modifications. Experiments are conducted to validate the effectiveness of the presented method.