Decentralized adaptive controller design for large-scale systems with higher order interconnections
TL;DR: In this article, the authors considered a general representation of interconnections when the strength of the interconnection is bounded by a pth-order polynomial in states, and designed two adaptive controllers with partially centralized compensation and a fully adaptive decentralized controller.
Abstract: Decentralized robust adaptive controller designs for large-scale interconnected systems are investigated. Motivated by real mechanical systems, the authors consider a general representation of interconnections when the strength of the interconnections is bounded by a pth-order polynomial in states. This is in contrast to other studies which have made simpler assumptions about the strength of the interconnections. The authors investigate several scenarios as the control computations become more distributed until the controllers are completely decentralized. The possible bound of the interconnections is assumed to be known for the decentralized semiadaptive controller. Without the knowledge of these bounds, two adaptive controllers are designed: a decentralized adaptive controller with partially centralized compensation and a fully adaptive decentralized controller. >
Citations
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TL;DR: The overview is focused on recent decomposition approaches in interconnected dynamic systems due to their potential in providing the extension of decentralized control into networked control systems.
417 citations
01 Jan 2010
TL;DR: It is proven that all the signals of the resulting closed-loop system are uniformly bounded and that the tracking errors converge to a small neighborhood around zero.
Abstract: A robust adaptive fuzzy control approach is developed for a class of multi-input-multi-output (MIMO) nonlinear systems with modeling uncertainties and external disturbances by using both the approximation property of the fuzzy logic systems and the backstepping technique. The MIMO systems are composed of interconnected subsystems in the strict-feedback form. The main characteristics of the developed approach are that the online computation burden is alleviated and the robustness to dynamic uncertainties and external disturbances is improved. It is proven that all the signals of the resulting closed-loop system are uniformly bounded and that the tracking errors converge to a small neighborhood around zero. Two simulation experiments are presented to demonstrate the feasibility of the approach developed in this paper.
289 citations
TL;DR: The controller is shown to maintain robustness for a wide class of systems obtained by perturbation in the dynamics of the original system, and appending additional subsystems does not require controller redesign for the original subsystems.
Abstract: Decentralized adaptive control design for a class of large-scale interconnected nonlinear systems with unknown interconnections is considered. The motivation behind this work is to develop decentralized control for a class of large-scale systems which do not satisfy the matching condition requirement. To this end, large-scale nonlinear systems transformable to the decentralized strict feedback form are considered. Coordinate-free geometric conditions under which any general interconnected nonlinear system can be transformed to this form are obtained. The interconnections are assumed to be bounded by polynomial-type nonlinearities. Global stability and asymptotic regulation are established using classical Lyapunov techniques. The controller is shown to maintain robustness for a wide class of systems obtained by perturbation in the dynamics of the original system. Furthermore, appending additional subsystems does not require controller redesign for the original subsystems. Finally, the scheme is extended to the model reference tracking problem when global uniform boundedness of the tracking error to a compact set is established.
255 citations
TL;DR: Presents a solution to the problem of decentralized adaptive asymptotic tracking for a class of large-scale systems using nonlinear output feedback using a recursive, decentralized, output-feedback design procedure.
Abstract: Presents a solution to the problem of decentralized adaptive asymptotic tracking for a class of large-scale systems using nonlinear output feedback. The proposed constructive approach does not require any matching conditions on the parametric uncertainties nor growth conditions of any kind on the subsystem and interacting output nonlinearities. Any decentralized system in the family may have an unknown, nonzero equilibrium point. Partially decentralized reduced-order filters are presented to recover the unmeasured states. The recursive, decentralized, output-feedback design procedure is illustrated in a practical example of two inverted pendulums on carts without velocity measurements. The effectiveness of the decentralized algorithm is supported by simulation results.
252 citations
TL;DR: A decentralized adaptive backstepping control scheme is proposed for a class of interconnected nonlinear time-varying systems and it is shown that the tracking errors can converge to predefined arbitrarily small residual sets with prescribed convergence rate and maximum overshoot, independent of the parameters variation speed and the strength of interactions.
234 citations
References
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Book•
01 Jan 1991
TL;DR: Covers in a progressive fashion a number of analysis tools and design techniques directly applicable to nonlinear control problems in high performance systems (in aerospace, robotics and automotive areas).
Abstract: Covers in a progressive fashion a number of analysis tools and design techniques directly applicable to nonlinear control problems in high performance systems (in aerospace, robotics and automotive areas).
15,545 citations
Book•
[...]
01 Jan 1989
TL;DR: Benefiting from the feedback of users who are familiar with the first edition, the material has been reorganized and rewritten, giving a more balanced and teachable presentation of fundamentals and applications.
Abstract: From the Publisher:
Written by two of the pioneers in the field, this book contains a wealth of practical information unavailable anywhere else. The authors give a comprehensive presentation of the field of adaptive control, carefully bending theory and implementation to provide the reader with insight and understanding. Benefiting from the feedback of users who are familiar with the first edition, the material has been reorganized and rewritten, giving a more balanced and teachable presentation of fundamentals and applications.
5,578 citations
TL;DR: In this article, the adaptive control of a class of large-scale systems formed of an arbitrary interconnection of subsystems with unknown parameters, nonlinearities, and bounded disturbances is investigated.
Abstract: The adaptive control of a class of large-scale systems formed of an arbitrary interconnection of subsystems with unknown parameters, nonlinearities, and bounded disturbances is investigated. It is first shown that no matter how weak the interconnections are, a decentralized adaptive control scheme can become unstable. Approaches are then developed for stabilization and tracking using new decentralized adaptive controllers. In the case where the relative degree n^{*} of the transfer function of each decoupled subsystem is less than or equal to two, sufficient conditions are established which guarantee boundedness and exponential convergence of the state and parameter errors to bounded residual sets. In the absence of disturbances and interconnections, the decentralized adaptive control schemes guarantee exact convergence of the tracking errors to zero. The effectiveness of the proposed adaptive schemes is demonstrated using a simple example.
482 citations
Book•
01 Jan 1983
TL;DR: This paper presents a new approach to adaptive control called reduced order-decentralized adaptive control, which aims to improve the robustness improvement of identifiers and adaptive observers in the presence of disturbances.
Abstract: 1. Introduction.- 2. Continuous-time identifiers and adaptive observers.- 3. Discrete-time identifiers.- 4. Robustness improvement of identifiers and adaptive observers.- 5. Adaptive control in the presence of disturbances.- 6. Reduced-order adaptive control.- 7. Decentralized adaptive control.- 8. Reduced order-decentralized adaptive control.- Corrections.
468 citations