Output feedback stabilization of stochastic feedforward systems with unknown control coefficients and unknown output function

Summary This article studied the global output feedback regulation problem for a class of uncertain nonlinear time delay systems subject to unknown measurement faults on sensors. Different from the existing works, we consider the unknown time‐varying delays on the system states and relax their conservative condition on nonlinear functions. By introducing two novel time‐varying gains, a new global output feedback regulation algorithm is proposed, which ensures control parameters can be chosen flexibly. The proposed linear‐like controller is independent of the unknown time‐varying delays. Moreover, it has a simple structure, which is convenient for the implementation in practice. Based on the Lyapunov stability theory, it is strictly proved that all signals of the resulting closed‐loop system are globally bounded with the designed controller. Finally, a simulation example is presented to illustrate the effectiveness of the proposed output feedback regulation algorithm.

Section: System Formulationmentioning

confidence: 93%

Global output feedback regulation of nonlinear time delay systems subject to sensor measurement faults

Chen

Guan

2020

“…Hence, the finite‐time stabilization for nonsmooth system is more challenging and interesting because it is totally nondifferentiable in the process of controller design. Recently, without involving unknown parameters, the finite‐time stabilization of stochastic low‐order nonlinear systems in a lower‐triangular form were considered in Reference by introducing the adding a power integrator technique . discussed the global stabilization for a class of stochastic feedforward systems with unknown control coefficients and the power r =1.…”

Section: Problem Formulation and Preliminariesmentioning

confidence: 99%

Finite‐time stabilization for a class of stochastic low‐order nonlinear systems with unknown control coefficients

Shao

et al. 2020

Summary This paper addresses the problem of finite‐time stabilization for a class of low‐order stochastic upper‐triangular nonlinear systems corrupted by unknown control coefficients. Unlike the relevant schemes, the control strategy draws into a dominate gain to cope with the deteriorative effects of both uncertain nonlinearities and unknown control coefficients without using traditional adaptive compensation method. Then, a state feedback controller is constructed by the adding a power integrator method and modified homogeneous domination approach, to ensure the finite‐time stability of the closed‐loop system. Finally, the effectiveness of proposed control strategy has been demonstrated by a simulation example.

“…Remark The input and output quantizations are simultaneously involved in system , making it more challenging but more practically meaningful than the controlled feedforward systems without quantization …”

Section: Problem Statement and Mathematical Preliminariesmentioning

confidence: 99%

“…In addition, the considered system models in this paper have unknown output functions, unknown control coefficients, and unknown time‐varying growth rates. ii.Although the feedback control schemes for nonlinear feedforward systems without quantization have been developed in the work of Jia et al and Zhu and Wang, they cannot be directly applied to the system concerned in this paper because the quantization errors may lead to the deterioration of system performance and even cause instability. Particularly, using the stability condition that the Lipschitz unknown output function belongs to a given sector mentioned in the work of Zhu and Wang can only deal with the uncertainty of the output function but cannot handle the error caused by the input quantization.…”

Section: Introductionmentioning

confidence: 99%

Quantized feedback control for nonlinear feedforward systems with unknown output functions and unknown control coefficients

Wang

Sun

2019

Summary This paper investigates the quantized feedback control for nonlinear feedforward systems with unknown output functions and unknown control coefficients. The unknown output function is Lipschitz continuous but may not be derivable, and the unknown control coefficients are assumed to be bounded. To deal with this challenging quantized control problem, a time‐varying low‐gain observer is designed and a delicate time‐varying scaling transformation is introduced, which can avoid using the derivative information of the output function. Then, based on the well‐known backstepping method and the sector bound approach, a time‐varying quantized feedback controller is designed using the quantized output, which can achieve the boundedness of the closed‐loop system states and the convergence of the original system states. Moreover, a guideline is provided for choosing the parameters of the input and output quantizers such that the closed‐loop system is stable. Finally, two simulation examples are given to show the effectiveness of the control scheme.