星上光学有效载荷的两级隔振研究

Dual-stage Vibration Isolation of Optical Payloads for Satellites

为实现星上光学有效载荷的高成像性能,对星上光学有效载荷的两级隔振进行了研究。所谓两级隔振,即除了对控制力矩陀螺群(CMGs)等执行机构振动源进行隔振外,还在光学有效载荷和星体之间加入隔振装置。首先建立了含有两级隔振系统以及CMGs和太阳帆板的整星动力学模型,并采用ADAMS工程软件验证了所推导模型的正确性;其次,在合理假设的基础上简化模型,分别求得由扰动源到星体和有效载荷的传递函数矩阵,分析CMGs隔振平台参数变化对姿态控制系统的影响,选择合理参数分析两级隔振系统的频域特性;最后通过数值仿真分析了两级隔振系统在星上应用的可行性,并通过频谱对比分析两级隔振系统对光学有效载荷姿态稳定度的改善程度。

In order to realize high quality imaging performance for the optical payload of a satellite, a dual-stage passive vi- bration isolation system is discussed in this paper. The first stage of vibration isolation is at the actuator disturbance source like the control moment gyros （CMGs）. The second stage of isolation is placed between the top of the satellite bus and the optical payload. Firstly, an integrated satellite dynamic model is built, including a dual-stage vibration isolation system, pyr- amid configuration CMGs and solar arrays, and the validity of this dynamic model is verified by ADAMS. Secondly, the sat- ellite system level dynamic model is simplified based on reasonable assumptions. The transfer function matrices from CMGs motion to satellite motion and that to optical payload motion are derived. The influence of the vibration isolation platform of CMGs on the attitude control system is analyzed. Then the frequency domain characteristics of this vibration isolation system are discussed in terms of the rationally selected parameters of the dual-stage passive vibration isolation system. Finally, the rationality of the parameters of the dual-stage vibration isolation system and the feasibility of its application are proved by numerical simulation. The simulation results illustrate the ameliorative effect of the dual-stage vibration isolation system on the attitude stabilization of the optical payload at the frequency of the rotor speed.