Electro-Aero-Mechanical Model of Piezoelectric Direct-Driven Flapping-Wing Actuator

We present an analytical model of a flapping-wing actuator, including its electrical, aerodynamic, and mechanical systems, for estimating the lift force from the input electrical power. The actuator is modeled as a two-degree-of-freedom kinematic system with semi-empirical quasi-steady aerodynamic forces and the electromechanical effect of piezoelectricity. We fabricated actuators of two different scales with wing lengths of 17.0 and 32.4 mm and measured their performances in terms of the stroke/pitching angle, average lift force, and average consumed power. The experimental results were in good agreement with the analytical calculation for both types of actuators; the errors in the evaluated characteristics were less than 30%. The results indicated that the analytical model well simulates the actual prototypes.