Adaptive output feedback tracking controller for a class of uncertain strict feedback nonlinear systems in the absence of state measurements
Adaptive output feedback tracking controller for a class of uncertain strict feedback nonlinear systems in the absence of state measurements
复制标题
DOI：
10.1080/00207721.2010.488755
复制
发表时间：
2012-02
影响因子：
4.3
通讯作者：
S. Salehi;M. Shahrokhi
中科院分区：
文献类型：
--
作者：
S. Salehi;M. Shahrokhi
针对一类严格反馈形式的不确定单输入单输出系统，提出了一种基于反推技术的自适应控制方案。假设系统输出及其导数是可用的。借助于可观性的概念，证明了这类系统存在一个一对一的映射，它将输出及其导数映射到系统状态。通过这种映射，并使用线性参数化逼近器，如模糊逻辑系统或神经网络，不确定的非线性动态和不可用的状态估计。所提出的自适应控制器保证闭环系统一致最终有界，且最小逼近误差对输出跟踪误差L2范数的影响被任意衰减。仿真结果证明了该方案的有效性。
In this article, design of an adaptive control scheme for a class of uncertain single-input single-output systems in strict feedback form via a backstepping technique has been proposed. It is assumed that system output and its derivatives are available. By virtue of the observability concept, it is shown that for this class of systems there exists a one-to-one map, which maps output and its derivatives to system states. By means of this mapping and using linearly parametrised approximators, such as fuzzy logic systems or neural networks, the uncertain nonlinear dynamics and unavailable states are estimated. The proposed adaptive controller guarantees that the closed-loop system is uniformly ultimately bounded and the influence of minimum approximation error on the L 2-norm of the output tracking error is attenuated arbitrarily. The effectiveness of the proposed scheme has been demonstrated through simulation results.