Adaptive Speed Control Of Ultrasonic Motor Based On Characteristic Model

Ultrasonic Motor, as a new type of motion control execution unit, its advantageshave been known to people and get increasingly extensive application.Appropriate form of control model is the basis of study on the control strategy.Researchers have to seek better ultrasonic motor system control modeling methods tosatisfy the higher control performance requirements. This paper discusses thecharacteristic model of ultrasonic motor, and it was theoretically proved that thecharacteristic model with online identification is equivalent to the high order actualultrasonic motor. This paper puts forward three methods to determine the initial valueof characteristic model parameters, and sets up characteristic model of two-phasetraveling wave ultrasonic motor. This model not only has a simple structure, but alsocan better express the characteristics of the ultrasonic motor compared with thetraditional identification model.Based on characteristic model, this paper designs the golden section speed controlof ultrasonic motor, including linear and nonlinear. Simulation results show that thecontrol strategy is effective, and get the initial value of control parameters. Insubsequent experiments, fixed parameters and adaptive golden section controllerwhich includes online identification can both make the motor operate stably in speedadjustable range; the control effect is good and has some robustness. Nonlinear goldensection adaptive controller has more advantages than the linear.Further, in order to improve the performance of the ultrasonic motor speedcontrol, this paper construct the all-coefficient adaptive control strategy, logic integraland differential control laws are proposed based on the golden section adaptive speedcontrol strategy. The experimental results show that the all-coefficient adaptive controlstrategy has good robustness, and the online computation is smaller.