基于最优PID和LQG算法的空间望远镜大口径快摆机构控制系统仿真
|
摘要
空间望远镜在观测时会受到不确定性扰动,这些扰动的特性为幅值小,频带宽,控制难,而且望远镜平台的振动成分大部分在10 Hz以内。为了减小这些低频振动造成的干扰,对空间望远镜的大口径FSM系统进行控制器设计使其能够对低频扰动具有良好的抑制作用,选择的控制算法为在ITAE指标最优情况下的PID算法和带有积分作用的LQG算法。利用Simulink对系统搭建模型,仿真结果表明:FSM系统在PID控制器作用下的响应时间为0.4 s,在LQG控制器作用的响应时间为0.04 s,且都无稳态误差。利用OICETS卫星的振动功率谱密度数据对系统的抑制能力进行验证,在低频段0~10Hz范围内:跟踪模式时,系统在PID控制器作用下,抑制能力为14.5 d B,系统在LQG控制器作用下,抑制能力为32.5 d B;瞄准模式时,系统在PID控制器作用下,抑制能力为10.3 d B,系统在LQG控制器作用下,抑制能力为23.6 d B。经过比较,该大口径FSM系统在LQG控制器作用下的系统性能明显优于在最优PID控制器作用下。
The observation by space telescope is subject to uncertain disturbances with small vibration swing and wide frequency bandwidth. These disturbances are hard to be controlled, and most of them are within 10 Hz. In order to reduce these low-frequency disturbances, a controller with large-aperture fast-steering mirror system is designed. A PID algorithm at the condition of optimal integrated time absolute error(ITAE) criterion and a LQG algorithm with integral action are used respectively in designing the controller. A simulation model based on Simulink platform is built, and the simulation results show that the PID controller and the LQG controller have good performances in dynamic response and steady-state response. Meanwhile they can effectively suppress the low-frequency disturbances. The response time is 0.4 s and 0.04 s when the system is controlled by the PID and the LQG respectively, and the system is without steady state error in both situations. The vibration power spectrum density data of OICETS satellite verify the suppression ability of the system. In low-frequency range of 0-10 Hz: under the tracking mode, the disturbance restrain ability of the systems with PID controller and with LQG controller are 14.5 d B and 32.5 d B, respectively; while under targeting mode, the disturbance restrain ability of the systems with PID controller and with LQG controller are 10.3 d B and 23.6 d B, respectively. The comparison results indicate that the LQG controller has a better performance than the optimal PID controller in large-aperture FSM system.
The observation by space telescope is subject to uncertain disturbances with small vibration swing and wide frequency bandwidth. These disturbances are hard to be controlled, and most of them are within 10 Hz. In order to reduce these low-frequency disturbances, a controller with large-aperture fast-steering mirror system is designed. A PID algorithm at the condition of optimal integrated time absolute error(ITAE) criterion and a LQG algorithm with integral action are used respectively in designing the controller. A simulation model based on Simulink platform is built, and the simulation results show that the PID controller and the LQG controller have good performances in dynamic response and steady-state response. Meanwhile they can effectively suppress the low-frequency disturbances. The response time is 0.4 s and 0.04 s when the system is controlled by the PID and the LQG respectively, and the system is without steady state error in both situations. The vibration power spectrum density data of OICETS satellite verify the suppression ability of the system. In low-frequency range of 0-10 Hz: under the tracking mode, the disturbance restrain ability of the systems with PID controller and with LQG controller are 14.5 d B and 32.5 d B, respectively; while under targeting mode, the disturbance restrain ability of the systems with PID controller and with LQG controller are 10.3 d B and 23.6 d B, respectively. The comparison results indicate that the LQG controller has a better performance than the optimal PID controller in large-aperture FSM system.
引文
[1]谭天乐,朱春艳,朱东方,等.航天器微振动测试、隔离、抑制技术综述[J].上海航天,2014,31(6):36-51.Tan Tian-le,Zhu Chun-yan,Zhu Dong-fang,et al.Overview of micro-vibration testing,isolation and suppression technology for spacecraft[J].Aerospace Shanghai,2014,31(6):36-51.
[2]曹小涛,孙天宇,赵运隆,等.空间大口径望远镜稳像系统发展现状及趋势[J].中国光学,2014,7(5):739-748.Cao Xiao-tao,Sun Tian-yu,Zhao Yun-long,et al.Current status and development tendency of image stabilization system of large aperture space telescope[J].Chinese Optics,2014,7(5):739-748.
[3]Sudey J,Schulman J R.In orbit measurements of Landsat-4 thematic mapper dynamic disturbances[J].Acta Astronaut,1985,12:485-503.
[4]Wittig M,van Holtz L,Tunbridge D E L,et al.In-orbit measurement of microaccelerations of ESA’s communication satellite OLYMPUS[C]//Proc.SPIE,1990,1218:205-214.
[5]Marchante E M,Munoz L.ARTEMIS satellite microvibrations testing and analysis activities[C]//Proc.48th International Astronautical Congress.Torino,Italy,1997.
[6]Toyoshima M,Araki K.In-orbit measurements of short term attitude and vibrational environment on the Engineering Test Satellite VI using laser communication equipment[J].Opt.Eng.,2001,40(5):827-1832.
[7]Jono T,Toyoshima M,Takahashi N,et al.Laser tracking test under satellite microvibrational disturbances by OICETS ATP system[C]//Proc.SPIE:Acquisition,Tracking,and Pointing XVI.2002,4714:97-104.
[8]Kamiya T,Ogura N,Lkebe K,et al.On-orbit evaluation of OICETS microvibration[C]//Proc.51st Space Sciences and Technology Conference.Japan Society of Aeronautical Space Sciences,Sapporo,2007,3E02:1-6.
[9]王站.颤振对星载TDICCD相机成像质量的影响分析[D].北京:中国科学院大学,2014.Wang Zhan.Platform jitter effect on image quality of spaceborne TDICCD Camera[D].Beijing:University of Chinese Academy of Sciences,2014.
[10]凡木文,黄林海,李梅,等.压电倾斜镜的高压驱动及高速控制[J].光学精密工程,2015,23(10):2803-2809.Fan Mu-wen,Huang Lin-hai,Li Mei,et al.High-voltage drive and control for piezoelectric fast steering mirror[J].Optics and Precision Engineering,2015,23(10):2803-2809.
[11]史少龙.空间望远镜精密稳像控制关键技术研究[D].北京:中国科学院大学,2014.Shi Shao-long.Research on control technology of precision image stabilization system in space telescope[D].Beijing:University of Chinese Academy of Sciences,2014.
[12]Guo Quanfeng,Li Wei,Dong Jihong,et al.Space focusing mirror assembly with flexure hinges[C]//Proc.SPIE.2014,9283:928306.
[13]史少龙,尹达一,龚惠兴.大口径快摆镜机构系统辨识及控制参数优化[J].中国惯性技术学报,2014,22(2);161-166.Shi Shao-long,Yin Da-yi,Gong Hui-xing.Large-aperture fast steering mirror system identification and controller parameter optimization[J].Journal of Chinese Inertial Technology,2014,22(2):161-166.
[14]Li H W.Study on the servo system of large telescope based on the internal model PID control strategy[C]//Proceedings of the 10th International Conference on Electronic Measurement and Instruments.Chengdu,China,2011:68-72.
[15]Maurya K,Bongulwar M R,Patre B M.Tuning of fractional order PID controller for higher order process based on ITAE minimization[C]//2015 Annual IEEE India Conference.
[16]Tahir1 F,Ohtsuka T.Using inverse linear quadratic method for systematic tuning of performance index in nonlinear model predictive control[C]//SICE Annual Conference.Akita University,Akita,Japan,2012.
[2]曹小涛,孙天宇,赵运隆,等.空间大口径望远镜稳像系统发展现状及趋势[J].中国光学,2014,7(5):739-748.Cao Xiao-tao,Sun Tian-yu,Zhao Yun-long,et al.Current status and development tendency of image stabilization system of large aperture space telescope[J].Chinese Optics,2014,7(5):739-748.
[3]Sudey J,Schulman J R.In orbit measurements of Landsat-4 thematic mapper dynamic disturbances[J].Acta Astronaut,1985,12:485-503.
[4]Wittig M,van Holtz L,Tunbridge D E L,et al.In-orbit measurement of microaccelerations of ESA’s communication satellite OLYMPUS[C]//Proc.SPIE,1990,1218:205-214.
[5]Marchante E M,Munoz L.ARTEMIS satellite microvibrations testing and analysis activities[C]//Proc.48th International Astronautical Congress.Torino,Italy,1997.
[6]Toyoshima M,Araki K.In-orbit measurements of short term attitude and vibrational environment on the Engineering Test Satellite VI using laser communication equipment[J].Opt.Eng.,2001,40(5):827-1832.
[7]Jono T,Toyoshima M,Takahashi N,et al.Laser tracking test under satellite microvibrational disturbances by OICETS ATP system[C]//Proc.SPIE:Acquisition,Tracking,and Pointing XVI.2002,4714:97-104.
[8]Kamiya T,Ogura N,Lkebe K,et al.On-orbit evaluation of OICETS microvibration[C]//Proc.51st Space Sciences and Technology Conference.Japan Society of Aeronautical Space Sciences,Sapporo,2007,3E02:1-6.
[9]王站.颤振对星载TDICCD相机成像质量的影响分析[D].北京:中国科学院大学,2014.Wang Zhan.Platform jitter effect on image quality of spaceborne TDICCD Camera[D].Beijing:University of Chinese Academy of Sciences,2014.
[10]凡木文,黄林海,李梅,等.压电倾斜镜的高压驱动及高速控制[J].光学精密工程,2015,23(10):2803-2809.Fan Mu-wen,Huang Lin-hai,Li Mei,et al.High-voltage drive and control for piezoelectric fast steering mirror[J].Optics and Precision Engineering,2015,23(10):2803-2809.
[11]史少龙.空间望远镜精密稳像控制关键技术研究[D].北京:中国科学院大学,2014.Shi Shao-long.Research on control technology of precision image stabilization system in space telescope[D].Beijing:University of Chinese Academy of Sciences,2014.
[12]Guo Quanfeng,Li Wei,Dong Jihong,et al.Space focusing mirror assembly with flexure hinges[C]//Proc.SPIE.2014,9283:928306.
[13]史少龙,尹达一,龚惠兴.大口径快摆镜机构系统辨识及控制参数优化[J].中国惯性技术学报,2014,22(2);161-166.Shi Shao-long,Yin Da-yi,Gong Hui-xing.Large-aperture fast steering mirror system identification and controller parameter optimization[J].Journal of Chinese Inertial Technology,2014,22(2):161-166.
[14]Li H W.Study on the servo system of large telescope based on the internal model PID control strategy[C]//Proceedings of the 10th International Conference on Electronic Measurement and Instruments.Chengdu,China,2011:68-72.
[15]Maurya K,Bongulwar M R,Patre B M.Tuning of fractional order PID controller for higher order process based on ITAE minimization[C]//2015 Annual IEEE India Conference.
[16]Tahir1 F,Ohtsuka T.Using inverse linear quadratic method for systematic tuning of performance index in nonlinear model predictive control[C]//SICE Annual Conference.Akita University,Akita,Japan,2012.