Modeling and Simulation for Multi-Rotor Fixed-Wing UAV Based on Multibody Dynamics

Accurate dynamic modeling lays foundation for design and control of UAV. The dynamic model for the multi-rotor fixed-wing UAV was looked into and it was divided into fuselage, air-body, multi-rotors, vertical fin, vertical tail and control surfaces, based on the multibody dynamics. The force and moment model for each body was established and derived into the Lagrange equation of the second king by virtual work. By electing quaternion as generalized coordinate and introducing Lagrangian multiplier, the dynamic modeling was deduced and established. Finally, the comparison between the simulation results and the experimental can be found that the present dynamic model accurately describes the process of dynamic change of this UAV and lay foundation for the control of UAV.