基于ESO的改进型滑模控制在转台中的应用

Application of Novel Sliding Mode Control in Flight Simulator Based on ESO

针对较强的摩擦、参数摄动及其他非线性干扰等不确定性因素严重影响飞行仿真转台伺服系统运动性能的问题,本文提出一种基于扩张状态观测器(ESO)和改进型滑模(NSMC)的复合控制策略。首先将上述所有扰动视为复合干扰,设计ESO对其进行实时估计和补偿,实现对原非线性控制系统的线性化动态补偿;然后针对转台系统快速、稳定、高精度等控制要求,采用具有强鲁棒性的滑模控制,在传统趋近率基础上设计改进型趋近率来提高收敛速度并抑制抖振。仿真结果表明,该控制方案能显著提高系统的动态跟踪性能并增强系统鲁棒性,具有可行性。

Aiming at the fact that uncertain factors include strong friction, parameter perturbation and other unknown interferences which cause serious influence to the flight simulator servo system, this paper gives a composite control scheme based on extend state observer （ESO） and novel sliding mode control （NSMC）. Firstly, all of the uncertain factors are treated as a composite disturbance. To convert the original nonlinear control system into a linear one, ESO is designed to achieve the real-time estimation and compensation for the composite disturbance. Secondly, in order to meet the fast, stable and high-accuracy requirement of the system, this paper adopts NSMC. A novel reaching law is also designed to improve the convergence speed and weaken the phenomenon of buffeting on the basis of traditional trending laws. Finally, the simulation results show that the control scheme can significantly improve the dynamic tracking performance of the system and enhance the robustness of system, which proves the proposed method is quite feasible.