动量轮微振动机理及仿真

动量轮是卫星等航天器姿态控制和精度保持的关键机械部件，其微振动严重影响卫星姿态稳定度和成像精度。动量轮的非均匀、非连续几何构形和旋转效应会引起结构系统的参数激励和载荷激励。针对具有非均匀力学特征参数的动量轮结构系统动力学模型，通过分析动力学方程中各矩阵参数的扰动，进行动量轮微振动机理的研究。仿真和试验结果表明:动量轮结构系统内部存在基频和高频激励，其中基频主要来自支点动载荷，高频来自轴承碾压作用；轮缘的局部振动会随转速形成前后行波。 

Micro-vibration mechanism and simulation of momentum wheel

Momentum wheel is the key mechanical component for attitude control and accuracy maintenance of spacecraft such as satellite. Its micro-vibration seriously affects attitude stability and imaging accuracy of satellite. The non-uniform, non-continous geometric configuration and rotational effects will cause parametric excitation and load excitation of the structural system. For the dynamic model of the momentum wheel structural system with non-uniform characteristic parameters, the micro-vibration mechanism is studied by analyzing the disturbance of each matrix parameter in the dynamic equation. The simulation and experimental results show that there are fundamental frequency and high frequency excitation in the momentum wheel structure system, where the fundamental frequency is mainly from the dynamic load of the fulcrum, and the high frequency is from the bearing rolling; the local vibration of the rim will form the traveling wave.