Mini-Size Hollow Inertia Ultrasonic Motor for Smart Phone Lens

In this paper, a novel miniature hollow inertial ultrasonic motor is proposed and manufactured. The motor consists three parts, transducer, friction pairs and slider. The motor is driven by the principle of inertia and exploit the difference between static and kinetic friction forces at the contact surface of friction pairs. Compact structure design and linear output make it suitable to serve in miniature zoom systemsuch as smart phone lens. Simulation in comsol was performed to analyze natural frequency and vibration mode of the motor. The influence of excitation signals and coulomb friction were tested. A prototype of this motor was manufactured and the mechanical experiments were performed. The results of simulation and experiments are analyzed and discussed.