Numerical Investigation of the Response of Active Bend-Twist PZT Actuator

Army combat operations have placed a high premium on reconnaissance missions for micro air vehicles (MAVs). An analysis of insect flight indicates that in addition to the bending excitation (flapping), simultaneous excitation of the twisting degree-of-freedom is required to manipulate the control surface adequately. By adding a layer of angled piezoelectric segments to a Pb(Zr,Ti)O3 (also referred to as PZT) bimorph actuator, a bend-twist coupling may be introduced to the flexural response of the layered PZT, thereby creating a biaxial actuator capable of driving wing oscillation in flapping wing MAVs. The present study presents numerical investigation of the response of functionally–modified bimorph designs intended for active bend-twist actuation of cm-scale flapping wing devices. The relationships of geometry and orientation of the angled segments with bimorph bend-twist response will be presented using results of finite-element analyses.