摘要:

A new technique for the digital control of continuous time systems is presented. This technique is based on a table look-up algorithm. To minimize the number of entries in the table, a grid embedding process is proposed. Using this process, an accurate, fast, and low-cost controller can be constructed using a table of a few thousand entries. The paper derives the control strategy and proposes a digital circuit to implement the controller. An example is presented in which the performance of a closed-loop digital controller is compared with that of an optimal regulator. The comparison shows that the performance of the new controller is very close to that of an equivalent optimal controller

ISSN:0020-7179    

DOI:10.1080/00207178708933964

出版商:Taylor & Francis Group    

年代:1987

数据来源: Taylor

摘要:

This paper discusses the periodic solutions of the matrix Riccati differential equation in the optimal filtering of periodic systems. Special emphasis is given to non-stabilizable systems and the question addressed is the existence and uniqueness of a steady-state periodic non-negative definite solution of the periodic Riccati differential equation which gives rise to an asymptotically stable steady-state filter. The results presented show that the stabilizability is not a necessary condition for the existence of such a periodic solution. The convergence of the general solution of the periodic Riccati differential equation to a periodic equilibrium solution is also investigated. The results are extensions of existing time-invariant systems results to the case of periodic systems

ISSN:0020-7179    

DOI:10.1080/00207178708933965

出版商:Taylor & Francis Group    

年代:1987

数据来源: Taylor

摘要:

Two-level, hierarchical, partially decentralized control is considered for a large-scale system composed ofMlinear static subsystems with an interaction and a quadratic performance index. The coordinator and the local controllers, using their different information, realize the control resulting from the global and local optimization, respectively. It is seen that the optimal control laws are linear functions of some estimates and are determined by the formulated two-level certainty equivalence principle. A discussion on the usefulness of the application of particular local controllers is described.

ISSN:0020-7179    

DOI:10.1080/00207178708933966

出版商:Taylor & Francis Group    

年代:1987

数据来源: Taylor

摘要:

The concept of complete decoupling is introduced in this paper. We show in particular that for any linear controllable system with non-singular transfer matrix, there always exists a static and differential state feedback such that the closed-loop system is completely decoupled.

ISSN:0020-7179    

DOI:10.1080/00207178708933967

出版商:Taylor & Francis Group    

年代:1987

数据来源: Taylor

摘要:

Three convergent procedures are presented. These determine a minimizing point of a relaxed optimal control problem defined by delay-differential equations with the control restricted to a compact convex subset of ℝmIn the first of these procedures, a strong variational algorithm due to Virk (1985 a) is extended to relaxed controls. The second uses a steepest descent approach. It is shown that both these procedures generate accumulation controls satisfying first-order necessary conditions of optimality. In the third procedure, the relaxed controls generated at each iteration are approximated using ordinary controls. When this is done, we show that limit points satisfy optimality conditions to within delta. Numerical performances of all three algorithms are also presented.

ISSN:0020-7179    

DOI:10.1080/00207178708933968

出版商:Taylor & Francis Group    

年代:1987

数据来源: Taylor

摘要:

In this paper, relations between the designs of functional observers and state feedback in the state space and transfer function approaches are presented. If the state space description of the plan can be written in a controllable canonical form, we show that the state space approach of the functional observer and state feedback design can be transformed in the transfer function approach form, Once the equations in the transfer function approach are solved, all unknown elements in the equations of the state space approach can be computed by an iterative algorithm. Thus, the relationship between the two approaches is established. We shall also show that the transfer function approach has fewer restrictions.

ISSN:0020-7179    

DOI:10.1080/00207178708933969

出版商:Taylor & Francis Group    

年代:1987

数据来源: Taylor

摘要:

This paper presents an effective adaptive controller for robotic manipulators. A perturbation difference model of the manipulator is established for the first time, based on which a modified pole assignment self-tuning control algorithm is developed. The controller is designed such that the variance of a generalized cost function is minimized and the controller parameters are estimated directly. Closed-loop pole assignment is achieved by adjusting on-line the weighting factors in the cost function. Simulations to a manipulator with three degrees of freedom are given to demonstrate the effectiveness of this self-tuning controller.

ISSN:0020-7179    

DOI:10.1080/00207178708933970

出版商:Taylor & Francis Group    

年代:1987

数据来源: Taylor

摘要:

In this paper we present a numerically reliable algorithm to compute the balanced realization of a stable state-space system that may be arbitrarily close to being unobservable and/or uncontrollable. The resulting realization, which is known to be a good approximation of the original system, must be minimal and therefore may contain a reduced number of states. Depending on the choice of partitioning of the Hankel singular values, this algorithm can be used either as a form of minimal realization or of model reduction. This illustrates that in finite precision arithmetic these two procedures are closely related. In addition to real matrix multiplication, the algorithm only requires the solution of two Lyapunov equations and one singular value decomposition of an upper-triangular matrix.

ISSN:0020-7179    

DOI:10.1080/00207178708933971

出版商:Taylor & Francis Group    

年代:1987

数据来源: Taylor

摘要:

A global Volterra series is developed for an analytic system defined on an analytic manifoldM. Local bilinearizations are pieced together using the theory of fibre bundles, giving rise to ‘twisted’ bilinear systems denned globally onM.

ISSN:0020-7179    

DOI:10.1080/00207178708933972

出版商:Taylor & Francis Group    

年代:1987

数据来源: Taylor

摘要:

Parallel to what was done for the balanced model reduction version of the phase approximation problem (see Li and Jonckheere 1987), this paper provides anL∞bound on the phase approximation error when one-step-at-a-time optimal Hankel norm model reduction is used to reduce the stable projection of the phase function matrix. The one-step-at-a-time Hankel norm procedure allows for anL∞phase error bound twice as small as that of the balanced version.

ISSN:0020-7179    

DOI:10.1080/00207178708933973

出版商:Taylor & Francis Group    

年代:1987

数据来源: Taylor