Design of a Novel Ultrasonic Motor Powered by a Langevin Type H-shaped Stator

A Langevin type H-shaped linear ultrasonic stator powered by its 1st anti-symmetric longitudinal mode and 2nd symmetrical bending modes was proposed. The motor's driving principle was detailed, and elliptical trajectory generated by particles on stator drive ends was derived. A FEM model was built to investigate the stator dynamic characteristics, so that the modal frequency sensitivities to some key geometric dimensions of stator were figure out, which results in longitudinal and bending working modal frequency being consistent. The stator's primary dimension was designed to be 37 mm×60 mm, and the motor's operating frequency is 49 kHz. Simulations were executed to work out the longitudinal and bending working modal vibration amplitudes to 8μm and 6μm on condition of 200 voltages, and to demonstrate the elliptical trajectories on driving ends, which validate the feasibility of the motor. This motor is expected to be used in precision positioning fields.