• nonlinear
• flapping wing
• dynamic
• anisotropy

This work is a preliminary study on the performance of a flapping Micro
Air Vehicle. The analyzed kinematic will be a forward flapping motion described by an anti-clockwise 8 cycle. In the analysis the aerodynamic forces are calculated off-line in case of a rigid wing, so the effect of aeroelastic
coupling will be no taken in consideration.
The simulations are performed with the commercial software NX NASTRAN and the in-house software of the Computational Aeroelasticity Lab of
SDSU, called CSHELL. Instead, the aerodynamic forces are provided by the U.S. Air Force Research Laboratory. First, the inhomogeneity of the wing in terms of mass distribution is
studied for the rigid case and it is shown that a higher density at the wing root is beneficial in respect to the mechanical power required to achieve the forward flight.
Then, the assumption of rigid wing is removed and the elastic deformation and its effects are investigated with the presence of structural geometric nonlinearities. The simulations showed that the inhomogeneity of the mass
distribution played a role similar to the rigid case. However, changing the
stiffness, especially in the wing span direction (anisotropy of the material)
seems to have major effects on the response of the wing.