Abstract: A simple contact model for describing the contact mechanics between stator and rotor of a traveling wave ultrasonic motor is presented. Using finite element method, effects of elastic modulus and friction factor of friction material on the contact state of stator and rotor are simulated numerically. The relationship between the deformation deep of friction material contacting with the stator and its elastic modulus is founded. Several friction materials are chosen and their effects on stall torque of ultrasonic motor are investigated experimentally. By means of experimental and calculational results, a more accurate contact deformation range of friction material is proposed. The result may provide theoretical guidance for choice and design of friction material of traveling wave ultrasonic motors.

Key words: Contact, Friction material, Numerical simulation, Ultrasonic motor