摘要:

A change of basis, from the standard set to the set of eigenvectors, provides the means for the decomposition of a multivariable problem into a set of scalar problems. This idea was deployed in an earlier paper to embed scalar generalised predictive control into the multivariable framework. Eigen-decompositions, however, can be sensitive to perturbations and cannot be applied to nonsquare matrices. The paper shows how an analoguous approach to multivariable predictive control can be based on a singular-value decomposition, and illustrates its applicability to nonsquare systems as well as demonstrates its superior sensitivity properties by means of two numerical examples.

DOI:10.1049/ip-d.1993.0021

出版商:IEE    

年代:1993

数据来源: IET

摘要:

A hybrid adaptive tracking controller for rigid-link flexible-joint (RLFJ) robot manipulators is designed. The controller is hybrid in the sense that an adaptive indirect controller is used to compensate for parametric uncertainties in the rigid-link equation whereas an adaptive robust controller corrects for the dynamics (i.e. mechanical flexibilities) and parametric uncertainty associated with the actuators. That is, in spite of these detrimental uncertainties and effects, we are still able to ensure a global asymptotic stability (GAS) result for the link position tracking error.

DOI:10.1049/ip-d.1993.0022

出版商:IEE    

年代:1993

数据来源: IET

摘要:

A simple recursive method for the computation of Gramians for stable linear continuous systems is proposed. The method is based on an extension of Åström-Jury-Agniel algorithm. The algorithms for the computation of controllability, observability, and cross Gramians for both SISO and MIMO systems are presented. The proposed method is illustrated by numerical examples and is also compared with the Lyapunov equation method of computing the Gramians.

DOI:10.1049/ip-d.1993.0023

出版商:IEE    

年代:1993

数据来源: IET

摘要:

The design of robust low-order controllers based on a high-order model of a generic flexible test structure with collocated sensors/ actuators is considered. A new synthesis technique which combines the projective and the positive-real control concepts is developed and used for control design. The proposed method alleviates the known difficulty of the projective approach where the residual (nonretained) closed-loop modes can become unstable, and guarantees the strictly positive realness of the controller. Two approaches for selecting the free design parameters of the design technique are provided. Based on the new technique, two global controllers and one decentralised controller are designed with their performance evaluated and compared.

DOI:10.1049/ip-d.1993.0024

出版商:IEE    

年代:1993

数据来源: IET

摘要:

Variations on the standard Kohonen feature map can enable an ordering of the map state space by using only a limited subset of the complete input vector. Also it is possible to employ merely a local adaptation procedure to order the map, rather than having to rely on global variables and objectives. Such variations have been included as part of a hybrid learning system (HLS) which has arisen out of a genetic-based classifier system. In this paper a description of the modified feature map is given, which constitutes the HLSs long term memory, and results on the control of a simple maze running task are presented, thereby demonstrating the value of goal related feedback within the overall network.

DOI:10.1049/ip-d.1993.0025

出版商:IEE    

年代:1993

数据来源: IET

摘要:

The LQG optimal continuous-time control philosophy is extended so that use may be made of future setpoint or reference signal information. The tracking error is defined in terms of an ideal response model so that a model following capability may also be introduced. A dual criterion cost function is employed that enables the feedback and reference input controllers to be designed independently. The solution of the problem is obtained in thes-domain following a polynomial-based optimisation procedure. This type of controller should be useful for continuous-time adaptive systems which require a predictive capability.

DOI:10.1049/ip-d.1993.0026

出版商:IEE    

年代:1993

数据来源: IET

摘要:

A robotic sub-sea inspection system is described. Emphasis is placed on how to use self-tuning adaptive control strategies to control the robot compliant motion. Experiments on a PUMA robotic manipulator have shown that adaptive control can greatly improve contact quality and provide much better tracking ability in an unknown environment. Also adaptive controllers can make the approach time shorter than ordinary fixed gain controllers. A coupled dynamics concept for surface contact, which is typical in an inspection task, is introduced. Implementation of an adaptive controller in VAL-2 is detailed. A supervisory control system, capable of incorporating real-time compliant motion control and written in MODULA-2, is also described.

DOI:10.1049/ip-d.1993.0027

出版商:IEE    

年代:1993

数据来源: IET

摘要:

The method of polynomial arrays may be effectively utilised in determining stability of polynomials containing literal coefficients. In the paper, the application of the polynomial array method to discrete-time systems is further investigated. Using tabular forms introduced by Bistritz and by Premaratne and Jury, both shift-operator and delta-operator formulated discrete-time systems are addressed. Critical stability constraints for such systems are obtained directly from these tabular forms. An important application of the proposed method is in digitising analogue systems with guaranteed stability.

DOI:10.1049/ip-d.1993.0028

出版商:IEE    

年代:1993

数据来源: IET

摘要:

The paper illustrates the use of parallel processing to simulate dynamical systems described by a complex high-dimensional set of ordinary differential equations. A substantial paradigm problem is drawn from the nuclear industry to illustrate the use of an integrated parallel processing methodology. This includes heuristic rules for algorithm and architecture selection, a classification for decomposition techniques, and their use in a well known and structured top-down approach. A new (parallel) version of the Davison–Cross stiff system solver is introduced and used in five different parallel processing configurations. Significant benefits owing to the extensive use of parallel emulation techniques to iteratively propose and refine candidate parallel processing solutions are highlighted.

DOI:10.1049/ip-d.1993.0029

出版商:IEE    

年代:1993

数据来源: IET

摘要:

The paper first briefly reviews the analytical procedures for obtaining optimum PID controller settings for minimisation of time weighted integral performance criteria. The approach is then used to obtain formulae for setting the controller parameters for a first-order plus dead time plant model which is a common approximation used in the process industries. These results are further extended to obtain two procedures, which can be used with the relay autotuning approach, to find the required controller parameters for optimisation of the integral of time error squared criterion. Good results have been obtained when these criteria are used with other plant models.

DOI:10.1049/ip-d.1993.0030

出版商:IEE    

年代:1993

数据来源: IET