Impacts on multi-layer piezoelectric actuator when coupled with mechanical elements

- MPA is normally used with one end fixed to ground/base and the other end joined with other mechanical part(s).
- The vibration characteristics of a MPA coupled with mechanical elements is simplified and mathematically modelled.
- Simulations are conducted to study the impacts including vibration resonant frequency and phase shifts.

Multi-layer piezoelectric actuators (MPA) have been widely used as linear actuators for various applications including micro/nano-positioning. When MPA is employed to drive a positioning mechanism, the arrangement normally involves one of its ends being fixed to the ground/base and the other end being joined with other mechanical part(s) of the device to be driven. Based on the IEEE standards on piezoelectricity and the verified assumptions, the vibration characteristics of a MPA, which has one end fixed and the other end coupled with mechanical elements, namely the equivalent mass, spring and damper is mathematically modelled. The derived equations are coded in Matlab and various values of the coupled mass, spring and/or damper are implemented to investigate the resulted impacts including changes of the vibration magnitudes at off-resonance frequencies and the shifts of resonant frequencies and phases.