Researches on the vibration characteristics of a new type of non-resonant piezoelectric stack motors

Abstract

To research on the mechanism of non-resonant linear piezoelectric motors, longitudinal vibration model and pseudo-rigid-body model were established for the stator of motor through the analysis of the construction and operating process of the motor. Then the longitudinal vibration differential equation and transverse vibration differential equation of the drive tip were produced. Thus longitudinal displacement function and transverse displacement function can be deduced. Utilizing the above researches, formula of average output force in a period was proposed for the motor. Finally, the prototype was designed and fabricated, vibration displacement is tested by laser displacement sensor and vibration displacement curves were fitted through origin software. Thus experiments on the longitudinal amplitude of drive tip were carried on. The output force of motor under different excitation conditions were measured with force measurement unit. Results proved the vibration characteristic theory of stator that the longitudinal amplitude of drive tip increases with excitation voltage and that the output force of motor increases with the longitudinal amplitude of drive tip. The output force prototype can be up to 3.5 N when the longitude amplitude of the stator is 0.95μm. The above researches can provide theoretical basis for structural optimization for the stator of motor.