A linear piezoelectric actuator with the parasitic motion of equilateral triangle flexure mechanism

Abstract

A parasitic type piezoelectric actuator with an equilateral triangle flexure mechanism is proposed and investigated to achieve large-stroke linear motion. Right-circular flexure hinges with different thicknesses (t1 and t2) are utilized in the design of the equilateral triangle flexure mechanism which is able to generate parasitic motion. The working principle is analyzed and illustrated by the theoretical simulation and finite element method (FEM) simulation. A prototype is manufactured to study the performance of proposed parasitic type actuator, together with an experimental system. Experiments indicate that the maximum stepping displacement is ΔL = 9.00 μm in the case that input voltage Ue = 150 V; the minimum stepping displacement ΔL = 0.24 μm is achieved under Ue = 60 V; the maximum speed is Vs = 180 μm s−1; the largest output force is F = 106.3 g under that input frequency f = 1 Hz and Ue = 100 V. This study demonstrates the feasibility of symmetrical triangle flexure mechanisms in the design of parasitic type piezoelectric actuators with large working stroke.