Bidirectional drive and multi-resolution adjustment across frequency bands in inertial impact piezoelectric motors via multimodal resonant vibration

An inertial impact piezoelectric motor capable of bidirectional movement and multiple displacement resolutions via the excitation of various vibrational modes was designed, assembled, and tested. Owing to its asymmetric structure, the motor operates at resonance under distinct vibrational modes through the adjustment of driving signal frequency, thereby outputting motion velocities in different directions and differentiated displacement resolutions. MATLAB was adopted to simulate the dynamic model; a motor prototype was fabricated, and an experimental platform was established to conduct performance tests on the motor. Experimental results demonstrate that the motor enables bidirectional movement and features four operational modes: In the first- (leftward) and second-order (rightward) modes, the maximum velocities reach 15.3 and 14.9 mm/s, with corresponding displacement resolutions of 171 and 28 μm, respectively. In the third- (leftward) and fourth-order (rightward) modes, the velocities are 0.356 and 0.295 mm/s, while the displacement resolutions achieve an ultrahigh precision of 0.238 and 0.116 μm, respectively. The motor has a maximum load capacity of 120 g.