A laminated ultrasonic motor operating in face expanding and face bending modes

In this work, a laminated ultrasonic motor operating in face expanding and face bending modes was designed, and a 5-layered ultrasonic motor prototype was fabricated and tested. By applying a sinusoidal electric field, the stator of the ultrasonic motor would produce the expanding/bending microscopic movement, then this microscopic movement was transformed into linear movement by friction force. Experimentally, the proposed ultrasonic motor revealed excellent performance under a relatively low driving voltage, where the maximum achievable output force and linear speed were respectively 1.5 N and 100 mm/s, under a sinusoidal driving voltage of 20 V_pp and 44.5 kHz. Compared with the previously reported ultrasonic motor, the proposed ultrasonic motor reveals many advantages, such as simple structure, excellent performance, and low driving voltage, demonstrating its promising applications in precise driving, high accuracy positioning, non-magnetic interference driving, etc.