A Fundamental Study in Nonlinear Aeroelastic Phenomena in Flapping Wing Micro Air Vehicles

Abstract : This report describes the development of an aeroelastic model capable of representing in an approximate manner the fundamental nonlinear aeroelastic behavior of flapping wing micro air vehicles in hover. The approximate nature of the model is due to an approximate nonlinear two dimensional unsteady aerodynamic model based on a vortex approach that accounts for the leading edge vortex shed from the leading edge of the flapping wing. This approximate aerodynamic model is coupled with a nonlinear structural dynamic model based on the MARC analysis package that is part of the NASTRAN code. The aeroelastic response solution is obtained from an updated Lagrangian approach for flapping wings with prescribed root motion that resembles insect or hummingbird wing flapping motion. It is shown that wing flexibility modifies the aeroelastic response of the wing, however these changes are relatively modest.