Dynamic characteristics analysis of quadrotor unmanned aerial vehicle

四旋翼无人机振动特性分析

¹ China Helicopter Research and Development Institute, Jingdezhen 333001, China
² National Key Laboratory of Helicopter Aerodynamics, Jingdezhen 333001, China

Received: 13 June 2025

Abstract

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.

摘要

针对四旋翼无人机支臂振动过大导致其飞行状态不稳的问题, 采用Nastran进行了有限元分析, 同时开展动特性试验和实际飞行试验进行振动分析。通过分析发现, 由于机体固有频率与激励频率相互耦合的共振作用, 无人机系统飞行时会发生剧烈振动。共振频率的模态振型主要是一阶摆振模态。文中提出增加撑杆的方式提高结构刚度, 从而规避支臂共振现象, 通过试验验证了该方法的有效性, 为多旋翼无人机动力学设计优化以及减振设计提供了参考依据。