Structural controllability of switched linear systems

This paper studies the structural controllability of a class of uncertain switched linear systems, where the parameters of subsystems’ state matrices are either unknown or zero. The structural controllability is a generalization of the traditional controllability concept for dynamical systems and purely based on the interconnection relation between the state variables and inputs through non-zero elements in the state matrices. In order to illustrate such a relationship, two kinds of graphic representations of switched linear systems are proposed, based on which graph theory-based necessary and sufficient characterizations of the structural controllability for switched linear systems are presented. Finally, the paper concludes with discussions on the results and future work.     

关于一类混合动态系统能控性与镇定的研究:一个例子

线性切换系统是一类重要的混合动态系统模型. 线性切换系统的镇定是一个基本研究问题. 针对一个线性切换系统的具体例子, 分析能控性和可镇定性的关系. 指出能控的线性切换系统是可以通过定常状态反馈镇定的.     

Reachability and controllability of switched linear discrete-timesystems

This paper investigates the reachability and controllability issues for switched linear discrete-time systems. Geometric characterization of controllability is presented. For reversible systems, the controllable sets and the reachable sets are identified in Wonham's geometric approach, and verifiable conditions for reachability and controllability are also presented     

Controllability and observability for time‐varying switched impulsive controlled systems

This paper is concerned with the controllability and observability for linear time‐varying switched impulsive systems. First, some new results about the variation of parameters for time‐varying switched impulsive systems are derived. Then less conservative sufficient conditions and necessary conditions for state controllability and observability of such systems are established. And for such system without impulsive control input, sufficient and necessary conditions for controllability and observability are derived. Furthermore, corresponding criteria applied to time‐varying impulsive systems are also discussed and examples are presented to show the effectiveness of the proposed results. Copyright © 2009 John Wiley & Sons, Ltd.     

On Controllability of Switched Linear Systems

This paper investigates the number of switchings and design of switching sequences for controllability of switched linear systems. Two related results are established. One is a new constructive approach to designing switching sequences. The controllable state set of each switching sequence designed via the approach coincides with the controllable subspace of switched linear systems. The other is a well-estimated value for the minimum number of switchings required for controllability. Each state in the controllable subspace can be steered to origin within this value of switching times.     

On partitioned controllability of switched linear systems

When a switched linear system is not completely controllable, the controllability subspace is not enough to describe the controllability of the system over whole state space. In this case the state space can be divided into two or three control-invariant sub-manifolds, which form a control-related partition of the state space. This paper investigates when each component is a controllable sub-manifold. First, we consider when a sub-manifold is controllable for no control input case. Then the results are used to produce a necessary and sufficient condition assuring the controllability of the partitioned control-invariant sub-manifolds of a class of switched linear systems. An example is given to demonstrate the effectiveness of the results.     

Recent advances on analysis and design of switched linear systems

A switched linear system is a special hybrid system that consists of a set of linear continuous-time/discrete-time subsystems and a rule that orchestrates the switching among them. The two-level (execution-supervision) structure makes the switched system theoretically interesting and practically attractive. Under active investigation for more than three decades, huge progress has been made in understanding the dynamical behavior of switched systems. In particular, it has been well recognized that, a switched linear system could produce highly nonlinear \& complex behaviors, for instance, controllability might not imply stabilizability, and stabilizability might not imply the existence of convex (control-)Lyapunov function. Through properly utilizing the rich dynamical behavior, it is possible to improve the system''s performance (controllability, stabilizability, adaptability, optimality, among many others) by means of systematic control/switching design. Meanwhile, many powerful tools, such as the common Lyapunov method and the logic-based switching design, have been developed for analysis and control of switched systems, which are also widely applied to other system frameworks like multi-agent systems and cyber-physical systems....     

A new perspective on criteria and algorithms for reachability of discrete-time switched linear systems

The paper presents a unified perspective on geometric and algebraic criteria for reachability and controllability of controlled switched linear discrete-time systems. Direct connections between geometric and algebraic criteria are established as well as that between the subspace based controllability/reachability algorithm and Kalman-type algebraic rank criteria. Also the existing geometric criteria is simplified and new algebraic conditions on controllability and reachability are given.     

Observability conditions of switched linear singular systems

The observability problem of switched linear singular(SLS) systems is studied in this paper. Based on the observability definition, the unobservable subspaces of given switching laws are investigated under the condition that all subsystems are regular. A necessary condition and a sufficient condition for observability of SLS systems are given. It is shown that the observability and controllability are dual for some special SLS systems with circulatory switching laws. The method developed here is applicable to the observability analysis of normal switched linear systems.     

Observability conditions of switched linear singular systems

The observability problem of switched linear singular(SLS) systems is studied in this paper. Based on the observability definition, the unobservable subspaces of given switching laws are investigated under the condition that all subsystems are regular. A necessary condition and a sufficient condition for observability of SLS systems are given. It is shown that the observability and controllability are dual for some special SLS systems with circulatory switching laws. The method developed here is applicable to the observability analysis of normal switched linear systems.     

Controllability of switched bilinear systems

The controllability of switched bilinear systems (SBLSs) is considered. Three kinds of controllabilities, including weak controllability, approximate controllability, and global controllability, are investigated one by one. Sets of easily verifiable sufficient conditions are obtained for each case, which are applicable to a large class of switched bilinear systems.     

一类混合动态系统的能控性和能观性研究

针对一类混合动态系统———周期型线性切换系统, 给出系统能控性、能观性的充分必要条件, 并通过例子加以验证.     

一类混合动态系统的能控性和能观性研究

针对一类混合动态系统--周期型线性切换系统,给出系统能控性、能观性的充分必要条件,并通过例子加以验证.     

Relative controllability of nonlinear switched fractional systems

This article investigates relative controllability of nonlinear switched fractional systems (SFSs). With the aid of Mittag-Leffler functions and invariant subspace theory, two sufficient and necessary conditions for corresponding linear SFSs are first established. Then, piecewise continuous control functions and a novel nonlinear operator are constructed to overcome the difficulties arising from switching rules, nonlinearity, and fractional derivatives. Under different constraints on nonlinear functions, two controllability conditions depending on system parameters for nonlinear SFSs are proposed by applying Schauder's and Banach's fixed point theorems, respectively. The obtained criteria may well show the influence of coefficient matrices, fractional derivatives, and switching rules on relative controllability. In addition, our proposed method is also applicable for integer-order switched systems. Finally, two simulated examples are worked out to verify the theoretical results.     

Accessibility of bilinear networks of systems: control by interconnections

We analyze controllability properties for a class of bilinear interconnected systems, consisting of networks of linear systems, where the coupling parameters act as control variables. We characterize the system Lie algebra of the resulting bilinear control systems. Necessary and sufficient conditions for accessibility are derived in terms of the underlying interconnection graph. Our results generalize earlier work by Brockett on controllability of bilinear output feedback systems, as well as recent work of Costello and Egerstedt on the control of information-exchange networks for distributed computing.     

Necessary and sufficient conditions for controllability and observability of switched impulsive control systems

Many practical systems in physics, biology, engineering, and information science exhibit impulsive dynamical behaviors due to abrupt changes at certain instants during the dynamical processes. This note first introduces the impulsive behavior into switched linear systems and studies the controllability and observability of such systems. Necessary and sufficient criteria for reachability and controllability are established. It is proved that reachability is equivalent to controllability for such systems. Then, necessary and sufficient criteria for observability and determinability of such systems are established by duality. It is also proved that observability is equivalent to determinability. Our criteria are of geometric type, they can be transformed into algebraic form conveniently. Finally, a numerical example is given to illustrate the utility of our criteria.     

Analysis and synthesis of switched linear control systems

Switched linear systems have a long history of interest in the control community, and have attracted considerable attention recently because they are not only practically relevant, but also tangible with the rich results in the linear system theory. Rapid progress in the field has generated many new ideas and powerful tools. This paper provides a concise and timely survey on analysis and synthesis of switched linear control systems, and presents the basic concepts and main properties of switched linear systems in a systematic manner. The fundamental topics include (i) controllability and observability, (ii) system structural decomposition, (iii) feedback controller design for stabilization, and (iv) optimal control.     

Controllability and reachability criteria for switched linear systems

This paper investigates the controllability and reachability of switched linear control systems. It is proven that both the controllable and reachable sets are subspaces of the total space. Complete geometric characterization for both sets is presented. The switching control design problem is also addressed.     

Controllability of product systems

For nonlinear continuous-time control systems we introduce the notion of controllability with selectable time, which is a little bit stronger than the usual controllability notion. For a large class of nonlinear systems on compact manifolds, controllability with selectable time is equivalent to controllability together with strong accessibility. It turns out that the controllability of products of independent control systems is related to this new controllability notion. The main result states that a smooth control affine product system is controllable if and only if all factors are controllable and at most one factor is not controllable with selectable time, provided the accessibility algebra of the product system has full rank.     

时变线性切换系统的指数镇定

研究满足驻留时间条件的时变线性切换系统的指数镇定问题.在一致完全可控条件下,引入带权可控性格拉姆矩阵设计出参数化的反馈控制器,利用比较原理给出状态转移矩阵的超调估计.针对驻留时间已知和未知两种情况,通过选择设计参数消除切换产生的超调影响,建立了两个指数镇定结论.最后以仿真实例验证本文结论.