基于扰动观测器的机载光电稳定平台自适应指数时变滑模控制

针对考虑载机干扰、摩擦力矩和参数不确定性等扰动因素影响的机载光电稳定平台高精度控制问题，提出了一种基于非线性扰动观测器的自适应指数时变滑模控制方法。该方法利用非线性扰动观测器观测系统的聚合不确定性，用来抵消外界扰动和参数不确定性对系统的干扰。在此基础上，设计自适应指数时变滑模控制器，实现了光电稳定平台伺服系统在残余聚合扰动影响下的期望角位置转动的全局鲁棒控制，该方法不需要确定聚合不确定性的上界信息，同时避免了普通自适应滑模的切换增益过度自适应问题，最终通过李雅普诺夫稳定性定理证明了闭环系统的全局渐近稳定性，系统角位置最终渐近收敛到期望角位置。数值仿真和样机测试结果表明，在外界扰动和参数不确定性的影响下，该方法能够实现系统的高精度角位置控制。

Adaptive Exponential Time-varying Sliding Mode Control based on Disturbance Observer for Photoelectric Stabilized AirbornePlatform

An adaptive exponential time-varying sliding mode control method based on a non-linear disturbance observer is proposed for a photoelectric stabilized airborne platform, taking aircraft torque fluctuations, nonlinear friction, and parameter uncertainty into consideration. The non-linear disturbance observer in the method is used to observe the composite uncertainty. The adaptive exponential time-varying sliding mode control module is integrated to realize global robust control of the angle rotation of the photoelectric stabilized platform impacted by residual disturbances not visible to the disturbance observer. The sliding mode controller is designed without the upper bound information of the composite uncertainty by the adaptive law. The exponential time-varying sliding mode function solves the problem of excessive adaptive for switch gain and improves the system response. According to Lyapunov's theory, the global asymptotically stable performance of the system is proved, and the angle position of system is asymptotically converged to the desired one. The simulation and prototype test results show that the method can achieve high-precision angle control despite external disturbances and parameter uncertainty.