杆式旋转超声电机在精密定位平台上的应用

摘要

介绍了一款杆式旋转超声电机,它由一个定子和两个转子构成,利用两个一阶弯曲振动模态工作。将该电机应用于驱动精密定位平台,并构建了基于计算机与GO-400运动控制器的精密定位平台控制系统。对于杆式超声电机,当利用专用驱动器供电,驱动器的输入电压为直流15V时,电机的空载转速为206r/min,堵转力矩为0.273N.m。对于精密定位平台,通过对电机进行正/反转控制、速度PID控制,实现平台的精密定位,定位精度达到2μm。进行了平台步进试验,其正/反向的位移分辨力都为1μm。利用旋转超声电机作精密定位系统的致动%A rod shape rotary ultrasonic motor utilizing the first bending vibration mode was provided,which was composed of one stator and two rotors.The motor was applied for the actuator of a precision positioning stage.A control system for the stage was designed based on computer and GO-400 motion controller.The motor was driven by an ultrasonic motor driver.When the applied voltage to one electric port was fixed at 15V,the motor speed without load was 206r/min and the maximum load torque was 0.273N·m.It is confirmed that the ultrasonic motor is suitable for achieving precise positioning of the stage with forward/reverse control and speed PID control.It is proved by experimental results that the positioning errors of the stage is less than 2μm and forward/reverse displacement resolutions of 1μm are achieved.The precision positioning stage driven by rotary type ultrasonic motors can use rotary optical encoders instead of expensive linear optical encoders.Thus,the price of precision positioning system can be significantly reduced.