Command Filtered Adaptive Fuzzy Control of Fractional-Order Nonlinear Systems With Unknown Dead Zones
针对分数阶非线性系统中的项爆炸和计算负担问题，提出一种命令滤波自适应反步控制器，利用模糊逻辑和分数阶命令滤波器降低复杂度，并通过误差补偿处理死区输入。
In the backstepping control of strict-feedback fractional-order nonlinear systems (FNSs), it is usually necessary to calculate the fractional derivatives of certain virtual control inputs, which results in the items explosion problem. In addition, as the system dimension mounts up, the computational burden increase sharply. In this article, a command filtered adaptive backstepping controller is implemented for uncertainty FNSs with nonsymmetric dead zone inputs. By using fuzzy logic systems to model system uncertainties, and designing fractional-order command filters to estimate virtual inputs together with their fractional-order derivatives, the items explosion problem is avoided and the computational complexity is reduced to a certain extent. An error compensation method is constructed to process filter errors, and the nonsymmetric dead zone nonlinearity input is solved by the bounded information of dead zone slopes. The validity of the proposed method is verified by theoretical verifications and simulation examples.