一种新型圆柱定子3自由度球形压电超声电机

New type of three-degree of freedom spherical piezoelectric ultrasonic motor with cylinder stator

3自由度超声电机利用圆柱定子的 3种同频共振模态 ( 2个正交的弯曲摇摆振动和 1个纵向振动 ) ,两两分别叠加、合成 ,通过摩擦驱动球转子分别绕 3个轴旋转 .根据这一原理可将该电机改装成多自由度直线电机 .通过有限元方法设计定子的结构和模态 ,利用阻抗测试方法测得的定子共振频率、模态与设计相符 ,同时测量了球转子绕 3个轴的转速特性 .为了提高 3自由度圆柱超声电机的定转子传动效率 。

A three degree of freedom (DOF) ultrasonic motor that uses a cylinder stator is developed. The three DOF ultrasonic motor can be constructed when three natural frequencies of a stator are made to correspond. When two of these natural vibrations, two bending modes perpendicular to each other and a longitudinal mode, a spherical rotor in contact with the stator head rotates around three perpendicular axes. The operational principle can realize multi DOF linear motion. The structure of three DOF ultrasonic motor is designed using finite element analysis. By using the impedance measurement, the natural frequencies and natural modes of vibration agree well with those calculated. In addition to the confirmation of three DOF motion, the basic characteristics of the three DOF motion, the rotational speed of the spherical rotor around three perpendicular axes were measured. To increase conversion efficiency from stator vibration to mechanical output of the three DOF motor, the optimized taper angle of the contact surface between cylinder stator and spherical rotor is constructed.