针对一类模型中存在未知非线性函数以及未知参数的阀控非对称液压缸电液位置系统，设计了一种自适应鲁棒控制策略以提高系统的跟踪精度和鲁棒性能.通过引入动态面技术，液压系统的非线性控制器设计过程可以被极大地简化，同时,传统的反步法所固有的复杂爆炸问题可以被有效地避免.通过设计基于不连续投影方法的自适应律，系统中的未知参数可以被有效地估计并补偿到控制器中.利用Lyapunov稳定性理论对闭环系统的稳定性进行了分析，Simulink的仿真结果表明所提出的算法能够有效地提高系统的跟踪性能.
A robust adaptive control strategy was proposed to improve the robustness and enhance the position tracking accuracy of valve controlled asymmetric cylinder position system with unknown nonlinearities and uncertain parameters. Dynamic surface control technique was introduced to avoid the inherent “explosion of complexity” problem of the traditional back stepping method, and the design process of the nonlinear controller could be simplified. By combining a discontinuous projection operator, the unknown parameters could be estimated effectively. The stability of the closed loop system was analyzed by using Lyapunov stability theory, and the simulation results have verified the effectiveness of the proposed control method.
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