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Xinkai Chen

Other affiliations: Electric Power University, Wakayama University, Mie University  ...read more
Bio: Xinkai Chen is an academic researcher from Shibaura Institute of Technology. The author has contributed to research in topics: Adaptive control & Control theory. The author has an hindex of 26, co-authored 201 publications receiving 3057 citations. Previous affiliations of Xinkai Chen include Electric Power University & Wakayama University.


Papers
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Journal ArticleDOI
TL;DR: It is proved that all the signals in the closed-loop system are semi-global uniformly ultimately bounded (SGUUB) in probability, the system output is driven to follow the reference signals, and all the states are ensured to remain in the predefined compact sets.

472 citations

Journal ArticleDOI
TL;DR: The purpose of the note is to show such a possibility by using the Prandtl-Ishlinskii (PI) hysteresis model to fuse available robust control techniques to have the basic requirement of stability of the system.
Abstract: Control of nonlinear systems preceded by unknown hysteresis nonlinearities is a challenging task and has received increasing attention in recent years due to growing industrial demands involving varied applications. In the literature, many mathematical models have been proposed to describe the hysteresis nonlinearities. The challenge addressed here is how to fuse those hysteresis models with available robust control techniques to have the basic requirement of stability of the system. The purpose of the note is to show such a possibility by using the Prandtl-Ishlinskii (PI) hysteresis model. An adaptive variable structure control approach, serving as an illustration, is fused with the PI model without necessarily constructing a hysteresis inverse. The global stability of the system and tracking a desired trajectory to a certain precision are achieved. Simulation results attained for a nonlinear system are presented to illustrate and further validate the effectiveness of the proposed approach.

323 citations

Journal ArticleDOI
TL;DR: This paper presents a new disturbance observer based on the variable structure system theory for minimum-phase (with respect to the relationship between the disturbance and output) dynamical systems with arbitrary relative degrees.
Abstract: This paper presents a new disturbance observer based on the variable structure system theory for minimum-phase (with respect to the relationship between the disturbance and output) dynamical systems with arbitrary relative degrees. The model uncertainties and the nonlinear parts of the system are merged into the disturbance term and are regarded as a part of the disturbances. The upper and lower bounds of the disturbance are assumed to be known as a priori information. Simulation results are presented to show the robustness and effectiveness of the new disturbance observer. Experimental results show the practicality of the new observer.

168 citations

Journal ArticleDOI
TL;DR: The proposed control law ensures the global stability of the controlled piezo-actuated stage, and the position error can be controlled to be as small as required by choosing the design parameters.
Abstract: The piezo-actuated stage is composed of a piezoelectric actuator (PEA) and a positioning mechanism (PM). Due to the existence of hysteretic nonlinearity in the PEA and the friction behavior in the PM, the accurate position control of the piezo-actuated stage is a challenging task. This paper discusses the adaptive sliding mode control for the piezo-actuated stage, where the hysteresis is described by the Prandtl-Ishlinskii model. This paper tries to fuse the hysteresis model with the adaptive control techniques, where the real value of the parameters of the stage need neither be identified nor be measured. The proposed control law ensures the global stability of the controlled piezo-actuated stage, and the position error can be controlled to be as small as required by choosing the design parameters. Experimental results show the effectiveness of the proposed method.

157 citations

Journal ArticleDOI
TL;DR: The quantized issue due to the use of computer is addressed by introducing a linear time-varying quantizer model where the quantizer parameters can be estimated on-line and the fuzzy approximator is used to avoid the identification of the parameters in the piezoelectric positioning stage.
Abstract: Focusing on the piezoelectric positioning stage, this paper proposes an adaptive estimated inverse output-feedback quantized control scheme. First, the quantized issue due to the use of computer is addressed by introducing a linear time-varying quantizer model where the quantizer parameters can be estimated on-line. Second, by using the fuzzy approximator, the developed controller can avoid the identification of the parameters in the piezoelectric positioning stage. Third, by constructing the estimated inverse compensator of the hysteresis, the hysteresis nonlinearities in the piezoelectric actuator are mitigated; Fourth, the states observer is designed to avoid the measurements of the velocity and acceleration signals. The analysis of stability shows all the signals in the piezoelectric positioning stage are uniformly ultimately bounded and the prespecified tracking performance of the quantized control system is achieved by employing the error transformed function. Finally, a computer controlled experiments for the piezoelectric positioning stage is conducted to show the effectiveness of the proposed quantized controller.

128 citations


Cited by
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Journal ArticleDOI
TL;DR: This survey gives a systematic and comprehensive tutorial and summary on the existing disturbance/uncertainty estimation and attenuation techniques, most notably, DOBC, active disturbance rejection control, disturbance accommodation control, and composite hierarchical antidisturbance control.
Abstract: Disturbance-observer-based control (DOBC) and related methods have been researched and applied in various industrial sectors in the last four decades. This survey, at first time, gives a systematic and comprehensive tutorial and summary on the existing disturbance/uncertainty estimation and attenuation techniques, most notably, DOBC, active disturbance rejection control, disturbance accommodation control, and composite hierarchical antidisturbance control. In all of these methods, disturbance and uncertainty are, in general, lumped together, and an observation mechanism is employed to estimate the total disturbance. This paper first reviews a number of widely used linear and nonlinear disturbance/uncertainty estimation techniques and then discusses and compares various compensation techniques and the procedures of integrating disturbance/uncertainty compensation with a (predesigned) linear/nonlinear controller. It also provides concise tutorials of the main methods in this area with clear descriptions of their features. The application of this group of methods in various industrial sections is reviewed, with emphasis on the commercialization of some algorithms. The survey is ended with the discussion of future directions.

1,849 citations

01 Jan 2005
TL;DR: In this paper, a number of quantized feedback design problems for linear systems were studied and the authors showed that the classical sector bound approach is non-conservative for studying these design problems.
Abstract: This paper studies a number of quantized feedback design problems for linear systems. We consider the case where quantizers are static (memoryless). The common aim of these design problems is to stabilize the given system or to achieve certain performance with the coarsest quantization density. Our main discovery is that the classical sector bound approach is nonconservative for studying these design problems. Consequently, we are able to convert many quantized feedback design problems to well-known robust control problems with sector bound uncertainties. In particular, we derive the coarsest quantization densities for stabilization for multiple-input-multiple-output systems in both state feedback and output feedback cases; and we also derive conditions for quantized feedback control for quadratic cost and H/sub /spl infin// performances.

1,292 citations

Journal ArticleDOI
TL;DR: This work presents a general framework for nonlinear systems subject to disturbances using disturbance observer based control (DOBC) techniques and develops a nonlinear disturbance observer for disturbances generated by an exogenous system.
Abstract: This work presents a general framework for nonlinear systems subject to disturbances using disturbance observer based control (DOBC) techniques. A two-stage design procedure to improve disturbance attenuation ability of current linear/nonlinear controllers is proposed where the disturbance observer design is separated from the controller design. To facilitate this concept, a nonlinear disturbance observer is developed for disturbances generated by an exogenous system, and global exponential stability is established under certain condition. Furthermore, semiglobal stability condition of the composite controller consisting of a nonlinear controller and the nonlinear disturbance observer is established. The developed method is illustrated by the application to control of a two-link robotic manipulator.

1,077 citations

Journal ArticleDOI
TL;DR: Sufficient conditions for exponential stability and weighted L"2-gain are developed for a class of switching signals with average dwell time and these conditions are given in the form of linear matrix inequalities (LMIs).

750 citations