摘要:

This paper presents a method for designing an ‘optimum’ unbiased reduced-order filter. For the proposed approach to work, the order of the filter must be greater than a certain minimum determined by the number of independent observations of the system available. The filler is much like a Luenberger observer for the state to be estimated, but with parameters optimized with respect to the noises in the system. A reduced-order innovation process is proposed that has properties similar to those of the full-order innovation process when the reduced filter is optimized. The approach offers the possibility of significant reduction in real-time computational requirements compared with the full-order filter, though at the cost of some loss of performance. The algorithm for the reduced-order filter is simple to implement— quite similar to that of the Kalman filter. An example is presented to compare the performance of the proposed method with the full-order Kalman filter.

ISSN:0020-7179    

DOI:10.1080/00207178708933852

出版商:Taylor & Francis Group    

年代:1987

数据来源: Taylor

摘要:

A fixed-interval reduced-order linear smoother is presented for continuous-parameter Markov processes. The smoother is a combination of two reduced-order linear niters. The Mayne-Fraser full-order smoother is shown to be a special case of this reduced-order smoother.

ISSN:0020-7179    

DOI:10.1080/00207178708933853

出版商:Taylor & Francis Group    

年代:1987

数据来源: Taylor

摘要:

A newly developed optimal frequency-domain approximation approach is proposed to treat the model matching problem in an easy way. Both the perfect model matching case and the imperfect model matching case are analysed in detail. With this novel approach, a best approximated model matching control scheme is established for the imperfect model matching case, while a perfect model matching system results whenever exact matching is possible. Compared with existing methods, the proposed method is conceptually simpler and computationally easier. Two examples are included to illustrate the technique presented.

ISSN:0020-7179    

DOI:10.1080/00207178708933854

出版商:Taylor & Francis Group    

年代:1987

数据来源: Taylor

摘要:

This paper is an extension of work published by Kacprzyk in 1983 in which, by using a fuzzy-logic-based calculus of linguistically quantified propositions, some generalizations of multistage decision making and control have been proposed. Namely, a new class of models has been developed that make it possible, roughly speaking, to find an optimal sequence of controls best satisfying (fuzzy) constraints and goals at, say, most (or any other suitable linguistic quantifier, for example ‘almost all’, ‘at least a few’) of the control stages. In this paper we further extend the above-mentioned approach by introducing discounting (a variable importance of particular control stages, in principle ‘the earlier the more important’). We propose a new model that can find an optimal sequence of controls best satisfying the (fuzzy) constraints and goals at, say, most of the earlier control stages. We employ a fuzzy-logic-based calculus of linguistically quantified propositions and develop a branch-and-bound algorithm for solving the problem. The approach may be viewed as an attempt to introduce commonsense knowledge, in its fuzzy-disposition-based representation due to Zadeh, into multistage decision making and control models.

ISSN:0020-7179    

DOI:10.1080/00207178708933855

出版商:Taylor & Francis Group    

年代:1987

数据来源: Taylor

摘要:

It is shown that receding-horizon controllers with horizon length N ≥ v (v being the controllability index of the system) stabilize a given discrete-time linear multi-variable system. Necessary and sufficient conditions for a receding-horizon controller to be a deadbeat controller are also given. It is further shown that by modifying a receding-horizon controller m of the poles of the closed-loop system (where m is the dimension of the input space) can be assigned to zero with simultaneous stabilization. The deadbeat properties of such modified receding-horizon controllers are also investigated,

ISSN:0020-7179    

DOI:10.1080/00207178708933856

出版商:Taylor & Francis Group    

年代:1987

数据来源: Taylor

摘要:

A method of designing robust sampled regulators for open-loop stable, linear, time-invariant, multivariable plants is given. The design procedure requires only the knowledge of the open-loop step response of the system and is independent of its structure. It allows the imposition of constraints on the maximum excursion of the inputs to the plant. The stability of the closed-loop system follows from its passivity and this, in turn, is obtained from a classical theorem of W. H. Young in the theory of trigonometric series. As a result it turns out that the stability of the algorithm is independent of the sampling rate. Moreover, the method of proving stability enables one to estimate the size of plant perturbations and/or measurement errors that can be tolerated before the onset of instability. Finally, a partial answer, leading to a Lyapunov-type equation, is also given to the question of the optimal choice of control parameters.

ISSN:0020-7179    

DOI:10.1080/00207178708933857

出版商:Taylor & Francis Group    

年代:1987

数据来源: Taylor

摘要:

The role of Kučera's two diophantine equations is explored in the optimization of a discrete-time feedback controller for a multivariate unstable plant subject to stochastic reference and disturbance, but it is usually only necessary to solve one of the equations. However, with an unstable plant, an extra diophantine equation must be solved when there is output measurement noise.

ISSN:0020-7179    

DOI:10.1080/00207178708933858

出版商:Taylor & Francis Group    

年代:1987

数据来源: Taylor

摘要:

The optimal linear estimators for distributed-parameter systems are derived in the case of pointwise observations that are time-averaged during the sampling interval. The filter structure derived is compared with that for the discrete-time observation case, and the finite-dimensional approximation of the results is presented.

ISSN:0020-7179    

DOI:10.1080/00207178708933859

出版商:Taylor & Francis Group    

年代:1987

数据来源: Taylor

摘要:

The analysis, parameter estimation and optimal control of linear time-varying digital systems are facilitated in this study. The discrete pulse orthogonal functions (DPOFs) and their operational matrices are taken as a sharp tool. The applications of DPOFs to digital control systems are analogous to those of the known block pulse functions (BPFs) in continuous systems. By applying the DPOFs, approximate solutions of digital time-varying systems can easily be obtained by convenient algorithms. Three examples are illustrated to demonstrate the proposed DPOF technique, and the approximate results are very accurate and satisfactory.

ISSN:0020-7179    

DOI:10.1080/00207178708933860

出版商:Taylor & Francis Group    

年代:1987

数据来源: Taylor

摘要:

The design of dynamic output feedback compensators for the pole assignment of linear time-invariant multivariable systems is considered. A systematic procedure is developed for the synthesis of the transfer function matrix of the compensator. A certain number of poles can be arbitrarily assigned by the proposed compensator. Moreover, in order to assign more poles using a compensator of the same order as before, a new approximate assignment approach based on the least-square-error algorithm is proposed. A numerical example is given to demonstrate the effectiveness of the proposed approaches.

ISSN:0020-7179    

DOI:10.1080/00207178708933861

出版商:Taylor & Francis Group    

年代:1987

数据来源: Taylor