In this paper, an adaptive output feedback control is framed for uncertain nonlinear discrete-time systems. The considered systems are a class of multi-input multioutput nonaffine nonlinear systems, and they are in the nested lower triangular form. Furthermore, the unknown dead-zone inputs are nonlinearly embedded into the systems. These properties of the systems will make it very difficult and challenging to construct a stable controller. By introducing a new diffeomorphism coordinate transformation, the controlled system is first transformed into a state-output model. By introducing a group of new variables, an input-output model is finally obtained. Based on the transformed model, the implicit function theorem is used to determine the existence of the ideal controllers and the approximators are employed to approximate the ideal controllers. By using the mean value theorem, the nonaffine functions of systems can become an affine structure but nonaffine terms still exist. The adaptation auxiliary terms are skillfully designed to cancel the effect of the dead-zone input. Based on the Lyapunov difference theorem, the boundedness of all the signals in the closed-loop system can be ensured and the tracking errors are kept in a bounded compact set. The effectiveness of the proposed technique is checked by a simulation study.

中文翻译：

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嵌套互连形式的一类非线性离散系统的神经输出反馈自适应控制

在本文中，针对不确定的非线性离散时间系统构建了自适应输出反馈控制。所考虑的系统是一类多输入多输出非仿射非线性系统，它们以嵌套的下三角形式存在。此外，未知的死区输入被非线性地嵌入到系统中。系统的这些特性将使其很难构建稳定的控制器。通过引入新的亚纯坐标变换，首先将受控系统转换为状态输出模型。通过引入一组新变量，最终获得了输入输出模型。基于转换后的模型，隐式函数定理用于确定理想控制器的存在，而逼近器用于近似理想控制器。通过使用平均值定理，系统的非仿射函数可以成为仿射结构，但是非仿射项仍然存在。自适应辅助项的设计巧妙地消除了死区输入的影响。基于李雅普诺夫差分定理，可以保证闭环系统中所有信号的有界性，并将跟踪误差保持在有界紧致集中。通过仿真研究验证了所提出技术的有效性。可以确保闭环系统中所有信号的有界性，并将跟踪误差保持在有界的紧凑集中。通过仿真研究验证了所提出技术的有效性。可以确保闭环系统中所有信号的有界性，并且将跟踪误差保持在有界紧凑集内。通过仿真研究验证了所提出技术的有效性。