航天用大力矩高精度超声波电机研究

Research on the high torque and high precision ultrasonic motor for aerospace application

超声波电机与传统电磁型电机不同 ,它是一种靠摩擦驱动的新原理电机 ,具有低速大力矩、响应快和功率质量比大等特点 ,能直接驱动 ,适合航天领域的应用。先简单介绍超声波电机的特点及其在航天领域的应用情况 ,随后介绍了所研制的一种低速大力矩超声波电机的结构、摩擦材料、特性和步进定位控制策略 ,其结构型式为纵扭复合型 ,样机直径为 80 mm ,堵转力矩达到了 13Nm,转速 12 .5 r/min,重复定位精度优于 0 .0 2 0°,纵扭振动的一阶谐振频率较接近 ,电机的工作频域较宽 ,近 7k Hz,起动时间在 5 m s左右 ,关断时间在 2 m s以内。

Ultrasonic motor is different from traditional electromagnetic motor and it is driven by friction force. Its character of low speed, high torque, quick response and high power/mass ratio and the quality of direct drive make it suitable for the application in the aerospace field. The paper first states briefly the trait of ultrasonic motor and its application in the aerospace field, hen introduces the motor's structure, friction material, characteristic and the stepping positioning control strategy of a kind of low speed and high-torque ultrasonic motor. It is hybrid longitudinal-torsional type ultrasonic motor. The diameter of the developed sample motor is 80 mm;the maximum output torque is 13 Nm:the steady rotating speed is 12.5 r/min and the repeating positioning accuracy can reach 0. 020 degree. It also has wide working frequency range (about 7 kHz). Its start up time is about 5 ms and the turn-off time is about 2 ms.