Dynamic characteristics analysis of quadrotor unmanned aerial vehicle

Because of the unstable flight state caused by the excessive vibration of the support arms of a quadrotor unmanned aerial vehicle(UAV), its finite element analysis is carried out with the Nastran, and its vibration analysis are also carried out for dynamic characteristic test and actual flight test. The above analysis results show that the coupling resonance of the natural frequency and excitation frequency of the UAV causes the dramatic vibration during its flight. The modal shape of its resonance frequency is mainly the first-order shimmy mode. This paper proposes the bracing rod addition method to improve the structural rigidity, so as to avoid the resonance of support arms. The experimental results verify the validity of the method. This study provides references for dynamic design optimization and vibration reduction design of multi-rotor UAVs.