Quasi-Steady Aerodynamic Modeling and Performance Analysis of an Ornithopter

This study presents an aerodynamic analysis of an ornithopter using a quasi-steady formulation based on the Modified Strip Theory. The model incorporates key unsteady aerodynamic effects, including viscous friction, partial leading-edge suction, and dynamic stall associated with high relative angles of attack during flapping motion. The aerodynamic predictions are employed to evaluate and optimize the wing kinematics specifically the flapping frequency, forward flight speed, and pitching amplitude to achieve adequate thrust and lift for sustained flight. A comprehensive performance assessment is conducted using metrics such as lift-to-weight ratio, thrust-to-drag ratio, input power coefficient, and propulsive efficiency. The results demonstrate the capability of the modified quasi-steady model to capture the dominant aerodynamics of flapping wings while providing an effective framework for kinematic optimization and preliminary ornithopter design.