A novel stick-slip piezoelectric actuator is developed based on a parallelogram flexible drive mechanism to minimize shear force

Abstract

A piezoelectric actuator utilizing a parallelogram flexible mechanism is proposed. This actuator harnesses the parasitic motion generated by a parallelogram driven by a piezoelectric element. It differs from existing actuation mechanisms based on a similar principle in that the piezoelectric stack is positioned on the outside of the parallelogram flexible mechanism, thus protecting it from shear forces. Finite element simulations and experiments confirm this. The analysis was conducted using theoretical analysis and finite element simulation. The optimal drive angle for the parallelogram flexible mechanism was determined through finite element simulation. Additionally, a prototype actuator and an experimental measurement system were developed to assess the operational performance of the proposed piezoelectric actuator. When the driving frequency is 475Hz and the locking force is 5N, the motion of the actuator achieves a maximum speed of 5.65mm/s and a maximum horizontal load of up to 113g; when the input frequency is 1Hz and the input minimum starting voltage is 8V, the minimum displacement resolution is 30nm. A comparative analysis of experimental results, theoretical calculations, and finite element simulation results demonstrates the feasibility of the structural design.