Analytical design model for a piezo-composite unimorph actuator and its verification usinglightweight piezo-composite curved actuators

Abstract

This paper describes an analytical design model for a layered piezo-composite unimorphactuator and its numerical and experimental verification using a LIPCA (lightweightpiezo-composite curved actuator) that is lighter than other conventional piezo-compositetype actuators. The LIPCA is composed of top fiber composite layers with high modulusand low CTE (coefficient of thermal expansion), a middle PZT ceramic wafer, and baselayers with low modulus and high CTE. The advantages of the LIPCA design are to replacethe heavy metal layer of THUNDER by lightweight fiber-reinforced plastic layers withoutcompromising the generation of high force and large displacement and to have designflexibility by selecting the fiber direction and the number of prepreg layers. In additionto the lightweight advantage and design flexibility, the proposed device can bemanufactured without adhesive layers when we use a resin prepreg system. Apiezo-actuation model for a laminate with piezo-electric material layers and fiber compositelayers is proposed to predict the curvature and residual stress of the LIPCA.To predict the actuation displacement of the LIPCA with curvature, a finiteelement analysis method using the proposed piezo-actuation model is introduced.The predicted deformations are in good agreement with the experimental ones.