Theoretical and Experimental Analysis of a Two Modes Excitation Linear Motor Using Piezoelectric Actuators

Classical linear travelling wave ultrasonic motors are based on the principle of tuning a RL circuit connected to piezoelectric transducer, to absorb the vibrations generated by a piezoelectric actuator and transmitted by a beam. This paper analyses theoretically and experimentally the principle of a different type of linear travelling wave motor. The device consists of two active piezoelectric vibrators that excite two consecutive modes of resonance in a vibrating beam. The sum of those modes creates a travelling wave motion on the beam. The article consists of a design stage based on vibrating beams theory followed by numerical simulation and concluded by a discussion based on the experimental measurements and results obtained from a real life prototype.