Chien Yi-Hsing, Wang Wei-Yen, Leu Yih-Guang, Lee Tsu-Tian
Department of Electrical Engineering, National Taipei University of Technology, Taipei 106, Taiwan.
IEEE Trans Syst Man Cybern B Cybern. 2011 Apr;41(2):542-52. doi: 10.1109/TSMCB.2010.2065801. Epub 2010 Sep 20.
This paper proposes a novel method of online modeling and control via the Takagi-Sugeno (T-S) fuzzy-neural model for a class of uncertain nonlinear systems with some kinds of outputs. Although studies about adaptive T-S fuzzy-neural controllers have been made on some nonaffine nonlinear systems, little is known about the more complicated uncertain nonlinear systems. Because the nonlinear functions of the systems are uncertain, traditional T-S fuzzy control methods can model and control them only with great difficulty, if at all. Instead of modeling these uncertain functions directly, we propose that a T-S fuzzy-neural model approximates a so-called virtual linearized system (VLS) of the system, which includes modeling errors and external disturbances. We also propose an online identification algorithm for the VLS and put significant emphasis on robust tracking controller design using an adaptive scheme for the uncertain systems. Moreover, the stability of the closed-loop systems is proven by using strictly positive real Lyapunov theory. The proposed overall scheme guarantees that the outputs of the closed-loop systems asymptotically track the desired output trajectories. To illustrate the effectiveness and applicability of the proposed method, simulation results are given in this paper.
本文针对一类具有某些类型输出的不确定非线性系统,提出了一种基于高木-关野(T-S)模糊神经网络模型的在线建模与控制新方法。尽管已经针对一些非仿射非线性系统开展了自适应T-S模糊神经控制器的研究,但对于更为复杂的不确定非线性系统却知之甚少。由于系统的非线性函数具有不确定性,传统的T-S模糊控制方法即便能够对其进行建模与控制,也会面临极大困难。我们并非直接对这些不确定函数进行建模,而是提出用一个T-S模糊神经网络模型来逼近系统的所谓虚拟线性化系统(VLS),该系统包含建模误差和外部干扰。我们还提出了一种针对VLS的在线辨识算法,并着重研究了基于自适应方案的不确定系统鲁棒跟踪控制器设计。此外,利用严格正实Lyapunov理论证明了闭环系统的稳定性。所提出的总体方案确保闭环系统的输出能渐近跟踪期望的输出轨迹。为说明该方法的有效性和适用性,本文给出了仿真结果。