超声波电机的接触摩擦模型对电机结构设计和性能优化具有重要作用。针对环形驻波超声波电机定转子接触摩擦问题，采用库伦摩擦+黏性摩擦定律建立了定转子接触摩擦模型。采用所建立的模型分析了一个振动周期内接触界面的摩擦力变化情况，也研究了定子不同径向振幅以及结构参数对电机输出性能的影响。最后，测量了电机的转矩转速特性，并将测量值与计算值进行对比，二者吻合度较好。另外，对比了基于库伦摩擦定律所建立模型的转矩转速特性计算值，对比结果表明，与基于库伦摩擦定律所建立的模型相比，基于库伦摩擦+黏性摩擦定律所建立的模型能更准确地描述定转子接触界面的摩擦传动特性。

Contact and friction model of ultrasonic motors is of great importance for structure design and performance optimization. In order to describe the contact and friction problems of a ring type standing wave ultrasonic motor, a contact and friction model of the stator and rotor is proposed based on the coulomb friction law with viscous friction. The variation of frictional force on the contact surface in one vibration cycle is investigated based on the proposed model. The impacts of different radial vibration amplitudes and structural parameters of the stator on the performances of the motor are analyzed. Finally, torquespeed characteristics of the motor are measured. The experimental values are compared with the calculated values, and the good agreements are obtained. In addition, the torquespeed characteristics calculated by using the model based on coulomb friction law are also compared. The comparison results show that the model based on coulomb friction law with viscous friction describes the friction drive characteristics on the contact surface more accurately than the model based on coulomb friction law.

国家自然科学基金项目（51777029，51507076）；江苏省“六大人才高峰”高层次人才项目（KTHY-040）；南京工程学院校级科研基金项目（CKJB202103）