Study On Feed Forward Control Method To Micropositioning System Driven By Pzt Baseing On Non-equiratio Model

The non-linear characteristic of the lead-zirconate-titanate actuator (PZT) is the mean reason which restrict the PZT working in high repeatability and frequency. Based on former fruit, several theoretical and practical problems of the non-linear characteristic are studied deeply in this paper. The mean works shown as follows:1.Basing on experiments, a new mathematical model(non-equiratio model) that characterize the non-linear of the PZT is presented. Using the new model, the non-linear curve of the minor loop of the PZT can be expressed by multiplying the non-linear curve of the mean loop by a transform matrix. The relatively error between the actual and the predicted modeling curve is 2% at most. Meanwhile, some characteristics of the non-equiratio model are discussed.2.Basing on the non-equiratio model and the characteristic of the PZT, this paper presents a new PED feedback control arithmetic with a model based feedforward loop. The results show that the PZT can accurately reproduce an arbitrary input signal with an error of less than 1.3%.3.The kinetic characteristic of the micropositioning system driven by the PZT and its boundary conditions should be feed are analyzed. Basing on the analyses, the applicability of the non-equiratio model to the micropositioning system is discussed and a new relatively controller is presented. The results show that the micropositioning system can accurately reproduce an arbitrary input signal with an error of less than 0.9% using the controller.4.The elements that restrict the micropositioning system achieving nanoresolution are analyzed. By eliminating the elements, 10 nanometers closed-loop resolution and 5 nanometers open-loop resolution are achieved in the working rang of 35 by 46 micrometers in the micropositioning system.