Miniature bulk PZT traveling wave ultrasonic motors for low-speed high-torque rotary actuation.

Traveling wave ultrasonic micromotors fabricated from a single layer of homogeneous bulk piezoelectric lead zirconate titanate (PZT) are described. The miniature motors are capable of bi-directional rotary motion with controllable speeds. By taking advantage of transverse interdigitated electrodes to excite traveling waves in a patterned bulk PZT substrate, the monolithic micromotor stators are patterned using a simple and low cost fabrication technique based on micropowder blasting.