摘要:

In this paper, linear discrete-time control systems of the formEkXk+1=AkXk+BkukYk=CkXk+Dkukare considered whereEkandAkarenot necessarily squarematrices. The problem to be solved is this. Find a system of the formÊkvk+1=Âkvk+[Bcirc]kƒk,uk=Ĉkvk+[Dcirc]kƒk, whereƒkis a partitioned column vector whose blocks are linear combinations of some of the output vectors of the original system and which possesses either or both of the following properties: (i) If the outputs of the original system areknown, then the output equation of the second system uniquely specifies the same inputs that generated the known outputs of the original system, (ii) If the output vectors of the original system aredesiredoutputs, then the equationuk=Ĉkvk+[Dcirc]kƒkyields one or more sequences of inputs for the original system that can generate the desired outputs. We shall furthermore seek the system which, among all systems having Property (i) or (ii) or both, has the smallest dimension for allk. (By dimension we mean the number of the elements ofxk) Making use of some results of Wilkinson (1978) on singular systems of linear differential equations, a procedure is developed that either yields a system having the properties listed above or provides evidence that there is no such system.

ISSN:0020-7179    

DOI:10.1080/0020718508961178

出版商:Taylor & Francis Group    

年代:1985

数据来源: Taylor

摘要:

Based on the state-space model of a dynamic system, a new steady-state and dynamic control loop interaction index is presented. Improved performance in the principal control loops may be achieved through implementation of internal control loops which enhance the system dynamics.

ISSN:0020-7179    

DOI:10.1080/0020718508961179

出版商:Taylor & Francis Group    

年代:1985

数据来源: Taylor

摘要:

Frequency-domain pole assignment and exact model-matching for delay systems are considered, with the knowledge that the delay plant is not necessarily stable. As for pole assignment for the delay plant, the state-space approach, which is also called the ‘time-domain approach’, is already known. The frequency-domain approach, which is much more fruitful than the time-domain approach, has not previously been developed, and is solved in this paper. As for exact model-matching, which is not only of a higher level but is also a more agreeable design method, neither the time-domain nor the frequency-domain approach has been reported. A newly developed frequency-domain exact model-matching approach is presented in this paper.

ISSN:0020-7179    

DOI:10.1080/0020718508961180

出版商:Taylor & Francis Group    

年代:1985

数据来源: Taylor

摘要:

An integrated design procedure is developed for a modified Smith predictor and associated controller for linear time-delay systems having transfer functions of the formk1,Aexp (—sT)/B, whereAandBare monic polynomials in s of degreen—landn, respectively.Ais Hurwitz andBhas a single right-half-plane root ats= λ. Forl=1,2,3, an augmented PI controller guarantees asymptotic stability for λTless than anl-dependent limit. The procedure forl= 3 is extended tol= 4 with the introduction of derivative action into the controller. Design arguments are on root locus topology, and on Nyquist analysis applied to an auxiliary system.

ISSN:0020-7179    

DOI:10.1080/0020718508961181

出版商:Taylor & Francis Group    

年代:1985

数据来源: Taylor

摘要:

In this paper we propose a simple method for order determination based on a generalized adaptive law which is used to adjust parameters in adaptive systems. The paper first reveals certain properties of the law and shows how they can be utilized for order determination in specific algorithms obtained from the law. The method requires no modifications of the algorithms but merely uses some quantities obtained directly from the algorithms. It can exhibit satisfactory performance in the noise-free case. Like other methods, however, it degenerates as noise increases. This degeneration is overcome by enhancing the original method by a correlation technique. Detailed discussions on the enhanced method are given.

ISSN:0020-7179    

DOI:10.1080/0020718508961182

出版商:Taylor & Francis Group    

年代:1985

数据来源: Taylor

摘要:

This paper is concerned with the sampled-data control of a continuous system in the situation where there exists delay for the control action after the measurement of the output at each sampling instant. The optimal control with the quadratic criterion function defined for the continuous system is adopted in this control problem. This paper shows that the problem can be transformed into the optimal control of a discrete system for the quadratic criterion function, and the variation of the control law to the sampling period and to the delay of the control action is clarified. The deterioration of cost performance with respect to delay is derived. A numerical example is also presented.

ISSN:0020-7179    

DOI:10.1080/0020718508961183

出版商:Taylor & Francis Group    

年代:1985

数据来源: Taylor

摘要:

The paper is concerned with the study of stability in the quadratic mean of dynamical systems described by Ito stochastic differential equations. In the first part of the paper, by using vector positive functions, conditions of asymptotic and exponential stability in the quadratic mean are developed. In the second part of the paper a comparison principle which reduces the stability analysis problem of stochastic dynamical systems to an analogous problem for a one-dimensional deterministic system is established.

ISSN:0020-7179    

DOI:10.1080/0020718508961184

出版商:Taylor & Francis Group    

年代:1985

数据来源: Taylor

摘要:

Bayes optimal recursive algorithms that do not require growing memory are obtained for the problems of fixed-interval, fixed-point and fixed-lag smoothing with uncertain observations. It is assumed that the signal sequence to be estimated is Markov and that the observations may contain the noise alone or the signal corrupted by noise (not necessarily additive). The uncertainty in the observations is governed by a Markov sequence, and the observation noise is an independent sequence. Under these assumptions, recursive algorithms are devised for thea posterioridensity ƒ(Xk\YN), for the three types of smoothing problem. The algorithms also yield a detection scheme of the sequential likelihood ratio test type, as to the presence or absence of the signal at each observation. The Bayes fixed-interval smoothing algorithm is applied to a Gauss-Markov example. The simulation results for this example indicate that the MSE performance of the Bayes smoother is significantly better than that of the linear smoother.

ISSN:0020-7179    

DOI:10.1080/0020718508961185

出版商:Taylor & Francis Group    

年代:1985

数据来源: Taylor

摘要:

For a class of dynamical systems, it is shown that trajectories which remain on the boundary of a non-empty, connected subset of a reachable set must be asymptotically stable. Using this result and a reachability maximum principle, we obtain a control law which will drive the system from the origin to the boundary of the reachable set for a class of two-dimensional linear control systems. Using this control law, the reachable set is easily constructed.

ISSN:0020-7179    

DOI:10.1080/0020718508961186

出版商:Taylor & Francis Group    

年代:1985

数据来源: Taylor