[1] [1] Zhou Taopin, Li Younian. Analysis and adaptive compen-sation of seeker disturbance torque [J]. Infrared and Laser Engineering, 2013, 42(7): 1830-1834. （in Chinese）

[2] [2] Jin Chaoqiong, Zhang Bao, Li Xiantao, et al. Friction compensation strategy of photoelectric stabilized platform based on disturbance observer [J]. Journal of Jilin University (Engineering and Technology Edition), 2017, 47(6): 1876-1885.

[3] [3] Mohammad Sheikh Sofla, Mohammad Zareinejad, Mohsen Parsa, et al. Integral based sliding mode stabilizing a camera platform using kalman filter attitude estimation [J]. Mechatronics, 2017, 44: 42-51.

[4] [4] Li Xiantao, Zhang Bao, Sun Jinghui, et al. ADRC based on disturbance frequency adaptive of aerial photoelectrical stabilized platform [J]. Infrared and laser Engineering, 2014, 43(5): 1574-1581. （in Chinese）

[5] [5] Hassan K Khalil. Nonlinear System[M]. Translated by Zhu Yisheng, et al. Beijing: Publishing House of Electronics Industry, 2011. (in Chinese)

[6] [6] Atta Oveis, Tamara Nestorovi. Robust observer- based adaptive fuzzy sliding mode controller [J]. Mechanical Systems and Signal Processing, 2016, 76-77: 58-71.

[7] [7] Syuan-Yi Chen, Sheng-Sian Gong. Hierarchical double integral sliding-mode control for second-order under actuated systems[C]//CACS International Automatic Control Conference, 2014: 173-178.

[8] [8] Dong Lili, Zhang Yao, Gao Zhiqiang. A robust decentralized load frequency controller for interconnected power systems [J]. ISA Transactions, 2012, 51: 410-419.

[9] [9] Pradhan R. Subudhi B. Double integral sliding mode MPPT control of a photovoltaic system[C]// IEEE Transactions on Control System Technology, 2016, 24: 285-292 .

[10] [10] Freidovich L B, Khalil H K. Performance recovery of feedback-linearization-based designs[C]//IEEE Trans Autom Control, 2008, 53: 2324-2334.

[11] [11] Kumar J, Kumar V, Rana K P S. Efficient reaching law for SMC with PID surface applied to a manipulator [C]// Computational Intelligence on Power, Energy and Controls with Their Impact on Humanity, IEEE, 2017: 51-56.

[12] [12] Chun Yin, Chen Yangquan, Zhong Shouming. Fractional-order power rate type reaching law for sliding mode control of uncertain nonlinear system [C]//Proceedings of 19th World Congress The international Federation of Automatic Control Cape Town, 2014: 2369-5374.

[13] [13] Tan S C, Lai Y M, Chi K. T. Indirect sliding mode control of power converters via double integral sliding surface[J]. IEEE Transactions on Power Electronics, 2008, 23(2): 600-611.

[14] [14] Mu Enxu, Ma Zhenqun, Feng Bin, et al. Friction compensation strategy for numerical control machine tools by reversing character analyzing[J]. Journal of Xi′an Jiao Tong Universigy, 2014, 48(8): 47-53. (in Chinese)

[15] [15] Zhao Jianzhou, He Chao, Zhang Yuhe. An experimental study of compensation algorithms for backlash nonlinearity of servo systems [J]. Journal of Beijing Institute of Technology, 2000, 20(3): 317-321. (in Chinese)

[16] [16] Zhu Huazheng, Fan Dapeng, Ma Dongxi, et al. Disturbance isolation index of seeker servo system and its test[J]. Optics and Precision Enginnering, 2009, 17(8): 1993-1998. (in Chinese)