A rabbit shaped bidirectional linear ultrasonic motor driven by single-phase signal.

A rabbit shaped block, single-phase, linear, ultrasonic motor is proposed. The motor is 17.7 × 9.1 × 6 mm3 in size, and the overall mass is 2.3 g. The motor is designed by referring to the rabbit running mode and the principle of a Langevin vibrator concentrator. It can realize bidirectional driving without changing the constraint position. First, the basic structure of the motor is introduced, and the working principle of the motor is discussed. Then, the motion trajectory and driving force of the motor driving foot are theoretically deduced and simulated, and the simulation results are verified by the modal impedance characteristic test. Finally, the mechanical characteristics of the motor prototype are tested. The results show that under the excitation voltage of 5 N preload and 200 Vpp, the motor is driven to the right in B1 mode, the no-load speed is 42.3 mm/s, the maximum driving force is 0.28 N, and the stall torque is 0.27 Nm. Correspondingly, the motor is driven in reverse in B2 mode, the no-load speed is 118 mm/s, the maximum driving force is 1.48 N, and the stall torque is 1.41 Nm.