高灵敏度空间光学载荷在轨微振动隔振系统设计与验证

Design and Verify of the Micro-vibration Isolation System for a Space-born High Sensitivity Optical Payload

卫星在轨飞行由于有动量轮等活动部件导致有微振动。一般载荷对微振动不敏感,但是高灵敏度的空间光学载荷,比如说亚米分辨率相机、时间调制干涉光谱仪等对微振动非常敏感。微振动会造成性能下降,甚至任务失败,因此微振动隔振系统设计是在轨高灵敏度载荷的关键技术之一。文章以某型号干涉仪为研究背景,系统研究了微振动对敏感载荷的影响、微振动振源的特性分析、微振动的隔振设计、地面试验验证等一系列问题。微振动对干涉仪敏感载荷影响的研究表明,干涉仪能够承受的加速度量级为1.0×10^(–2)g_n。采用考虑卫星传递影响的全链路仿真方法对卫星微振动振源的幅值进行了分析,结果表明干涉仪安装位置的微振动幅值为2.4×10^(–2)g_n,超过了其承受能力,需要采用隔振系统保证干涉仪在轨工作环境。进一步的扰振源扰振特性测试明确了微振动的频率,并以此为依据开展了隔振系统的设计;最终的地面微振动试验结果表明,隔振系统有效地保证了干涉仪的星上振动环境,从而验证了隔振系统设计的正确性和有效性。

The movement of the moving parts in the satellite such as the momentum wheel can result in micro-vibration on orbit,which will be very harmful to the high sensitivity optical payloads,which included the sub-meter resolution camera and Fourier transform spectrometer.Micro-vibration can degrade the system performance and even lead to the failure of the mission.Therefore,the micro-vibration isolation system has been one of the key technologies in the high sensitivity optical payloads.In this paper,an interferometer is used as the research background,many problems in the micro-vibration isolation were discussed,including the impact of the micro-vibration on the payload,the characteristics of the micro-vibration sources,and isolation design and ground verification for the micro-vibration.The maximum acceleration level that the payload can survive,about 1×10^（–2）g_n,was obtained by the micro-vibration sensitivity analysis.Meanwhile,the actual acceleration level at the mounting interface of the payload,computed by the coupled structural dynamic analysis considering the whole micro-vibration transfer path,was about 2.4×10^（–2）g_n,nearly twice of the allowable value.The analysis results showed that isolation system is necessary for the payload.More tests were executed to distinguish the micro-vibration frequencies,and then isolation system was designed.Ground test based on the payload platform was done,and the results showed the rationality and the validity of the isolation system design.