Resonant-type inertia linear motor based on the harmonic vibration synthesis of piezoelectric bending actuator

• A piezoelectric inertia linear motor based on the harmonic bending vibration synthesis is proposed.
• A piezoelectric bending actuator was designed by using the three modifying methods we studied.
• A prototype resonant-type piezoelectric inertia linear motor was designed, fabricated and tested.
• The PILM driving mechanism in one period is studied.

Traditional piezoelectric inertia motors are generally driven at the quasi-static frequency range, which results in a relatively slow moving speed. In this paper, a piezoelectric bending actuator was designed for a resonant-type inertia linear motor. The driving mechanism of the actuator was also studied. The actuator's movement in a periodical sawtooth-shaped waveform was generated by composing two sinusoidal resonant bending vibrations with a frequency ratio of 1:2. A prototype inertia motor was fabricated. Experimental results confirmed the effectiveness of the design. The no-load maximum speed was 28.2 mm/s with drive voltage of 300 Vp–p for a base frequency of 587 Hz. At a preload force of 9.6 N and a driving voltage of 400 Vp–p for the base frequency, the linear speed was 18.5 mm/s with 0.02 N drag load. The moving direction could be reversed by changing the driving voltage's phase.