Preliminary Study on Stability of a Hovering Bi-flap Flapping Wing Platform using Cycle-Averaged Linear Models

Abstract

A preliminary study on the stability of a bi-flap flapping wing hovering platform is presented in this paper. The work includes the derivation of cycle-average linear longitudinal and lateral models, the experiment to determine the stability derivatives, and analysis on the identified system matrices. Also discussed in the paper is the validity of using a cycle-averaged model to represent the dynamics of the flapping wing platform, and the validity of using small perturbation theory to linearize the nonlinear model. Results show that the platform is unstable longitudinally and laterally about the hovering equilibrium. Longitudinally, the natural modes are short period unstable oscillatory mode, fast subsidence mode, and slow divergent mode. Laterally, the natural modes are neutral mode, fast subsidence mode, and long period unstable oscillatory mode.