Gao Yuanpeng, Zhang Quan, Wei Chuanxin, Zhu Yuji, Li Qingling, Yin Dayi
CAS Key Laboratory of Infrared System Detection and Imaging Technology, Shanghai Institute of Technical Physics, Shanghai 200083, China.
Shanghai Institute of Technical Physics of the Chinese Academy of Sciences, Shanghai 200083, China.
Rev Sci Instrum. 2023 Nov 1;94(11). doi: 10.1063/5.0166967.
In view of the complex working environment of space astronomical telescopes, the influence of various disturbance sources on the imaging quality cannot be ignored. This paper focuses on compensating for the space telescope line-of-sight (LOS) deviation and suppressing the low-frequency disturbance problem in astronomical observation. A closed-loop control method based on dual-port adaptive internal model control (AIMC) for the fine image stabilization system (FISS) was proposed. To be specific, the fine guidance sensor (FGS) as the high-precision detection unit of the FISS calculates the telescope LOS deviation and sends it to the controller unit in real time. The controller unit drives the large-aperture fast steering mirror (FSM), which performs high-precision two-dimensional rotation to compensate for the telescope LOS deviation, according to the dual-port AIMC control algorithm. Moreover, the dual-port AIMC control method adds an AIMC loop on the basis of the feedback loop and adjusts the filter parameters adaptively according to the target angular velocity of the FSM, achieving higher disturbance suppression capability. The experimental results verify that the control method proposed can effectively compensate for the LOS deviation and suppress the composite frequency disturbance. In the 0-8 Hz frequency band, the power spectral density integral values of the star centroid deviation in the X and Y directions of the FGS are, respectively, suppressed by 97.38% and 98.38%.
鉴于空间天文望远镜工作环境复杂，各种干扰源对成像质量的影响不容忽视。本文重点研究补偿空间望远镜视线（LOS）偏差并抑制天文观测中的低频干扰问题。提出了一种基于双端口自适应内模控制（AIMC）的精细图像稳定系统（FISS）闭环控制方法。具体而言，作为FISS高精度检测单元的精细制导传感器（FGS）计算望远镜LOS偏差，并实时将其发送到控制器单元。控制器单元根据双端口AIMC控制算法驱动大口径快速转向镜（FSM），FSM进行高精度二维旋转以补偿望远镜LOS偏差。此外，双端口AIMC控制方法在反馈回路的基础上增加了一个AIMC回路，并根据FSM的目标角速度自适应调整滤波器参数，实现了更高的干扰抑制能力。实验结果验证了所提出的控制方法能够有效补偿LOS偏差并抑制复合频率干扰。在0-8Hz频段，FGS在X和Y方向上的星质心偏差功率谱密度积分值分别被抑制了97.38%和98.38%。
