Nonlinear modeling of a miniature fixed-pitch coaxial UAV

This paper presents the work that has been done to derive an accurate nonlinear model for a miniature fixed-pitch coaxial helicopter. Starting from the Newton-Euler rigid body dynamic equations, forces and torques generated at various parts of the UAV have been identified and formulated. The physical meanings behind the model are clearly explained, and the methods of identifying all the important model parameters are also provided. The full model is verified by comparing simulation results and actual flight tests with the NUS FeiLion coaxial UAV. The agreement between the two is promising.