四旋翼飞行器齿轮箱-支臂组件动态特性分析

为提高重载油动四旋翼飞行器的稳定性，研究齿轮箱-支臂组件动态特性并进行结构优化。利用Lanczos特征值求解器，进行齿轮箱-支臂组件模态分析，并通过试验采集组件中心位置的振动加速度值，优化芯轴长径比。采用Runge-Kutta法编程求解组件的动力学方程，揭示组件振动的规律和影响因素。研究结果表明：传动芯轴长径比超过20会产生较大弯曲振动，优化传动芯轴长径比（＜14）可有效改变其固有频率，避开激励频率及倍频；振动加速度随转速增大先增大、后减小，当激励频率与系统固有频率相等时达到最大；通过优化斜支撑的角度提高组件刚度可实现减振。

Analysis of Dynamic Characteristics of Four-rotor Aircraft Gearbox-arm Component

The dynamic characteristics of gearbox-arm component are analyzed to improve the flight stability of a heavy-duty oil-powered four-rotor aircraft. The Lanczos eigenvalue solver is used to solve the modal of gearbox-arm component. The vibration acceleration value at the center of the component is collected through experiment，and the length-to-diameter ratio of mandrel is optimized. Runge-Kutta method is used to solve the dynamic equation of the component，and the law of vibration and influencing factors of the component are summarized. The results show that the mandrel's length-to-diameter ratio greater than 20 will produce larger bending vibration. The length-to-diameter ratio (<14) of the mandrel can be optimized to change the natural frequency of its vibration，and avoid the excitation frequency and frequency multiplication. The vibration acceleration increases first and then decreases with the increase in rotating speed，and reaches the maximum when the excitation frequency is equal to the natural frequency of the system. The stiffness of the system is improved to achieve vibration reduction by optimizing the angle of the inclined support.