摘要:

The optimal control of manipulators is a key to the success of automated manufacturing. The problem considered here is an energy minimisation problem with given dynamics and is subject to actuator constraints. A differential dynamic programming algorithm is developed to solve the discrete-time optimal control problem. This method allows calculation of the joint refer ence trajectories and the design of a proportional derivative regulator. The characteristics of this new method are exposed and the simulation results shown.

DOI:10.1049/ip-d.1991.0071

出版商:IEE    

年代:1991

数据来源: IET

摘要:

The idea of distributed planning and problem solving as a reliable and effective methodology for air traffic control is introduced. Some basic concepts and terminology of distributed planning are first discussed, then a novel coordinator-coworker structure is described; this is a control mechanism that can dynamically reorganise the planning system in response to the task at hand. The information structure supporting such a control mechanism is made up of hierarchically organised distributed scratch pads. It also provides the basis for ‘self-repairing’ when individual nodes fail to operate, and allows for a graceful degradation of the whole system. The problems of air traffic control are analysed and the kernel design of the airborne processors in a location-centred co-operative planning system is described. The simulation-based planning process and its timing and selection considerations are explained. Three different organisational structures are implemented: the local centralised archi tecture, and the location-centred co-operative planning system with one- and two-level co ordinator-coworker hierarchies. The vehicle of the empirical studies, the distributed air traffic control testbed, is then introduced, and performance mea sures of the three organisational structures are compared in it. Finally, the design and the results of a series of experiments performed are discussed.

DOI:10.1049/ip-d.1991.0072

出版商:IEE    

年代:1991

数据来源: IET

摘要:

The present theory on the iterative learning control scheme requires the same initial condition at every iteration. The difficulty of this requirement is examined by showing that the learning control scheme proposed by Arimotoet al. can diverge for small mismatches as the trial learning is repeated indefinitely.

DOI:10.1049/ip-d.1991.0073

出版商:IEE    

年代:1991

数据来源: IET

摘要:

A simple method for solving the matrix Lyapunov equation for linear continuous systems with the system matrix in companion form is proposed. If the system is asymptotically stable, the solution of the Lyapunov equation can be obtained directly from the entries of a Routh table. The proposed method does not involve solution of a linear system of equations or matrix inversion and hence is computationally efficient compared to other techniques. It is illustrated by a numerical example.

DOI:10.1049/ip-d.1991.0074

出版商:IEE    

年代:1991

数据来源: IET

摘要:

In the paper, a few new results are presented relating to model reference control (MRC) and model reference adaptive control (MRAC) for nonlinear uncertain plants of a very general nature. Noa prioriknowledge about the structure of uncertainties (plant terms and coefficients) is assumed, nor is any constant bound on their values. Such plant models result from many applications. In particular, if uncertainties represent some unmodelled dynamic effects, they will depend on the system states and so be unbounded. The Lyapunov type of stability is considered. A new MRAC law has been developed, which provides stable tracking to within a certain comput able tolerance. The paper includes a few examples of the application of the developed adaptive con troller to nonlinear plants with potentially unbounded terms. The tracking control of robotic manipulators has been especially elaborated.

DOI:10.1049/ip-d.1991.0075

出版商:IEE    

年代:1991

数据来源: IET

摘要:

A recursive fixed-point-type method is presented to find the optimal control of a state-variable model of the megawatt-frequency control problem of multiarea electric energy systems. The results give the numerical decomposition so that only low-order systems are involved in algebraic computations. This approach is conceptually simple and produces considerable savings of computation.

DOI:10.1049/ip-d.1991.0076

出版商:IEE    

年代:1991

数据来源: IET

摘要:

The problem of input-output decoupling and simultaneous pole assignment for generalised state-space systems via pure proportional-state feedback is studied. A new design approach is presented for the derivation of the general analytical expressions of the decoupling controller matrixes and of the diagonal elements of the transfer function of the decoupled closed-loop system. On the basis of this approach, the first results on the structural properties of the closed-loop system are established covering the arbitrariness of the poles of the general form of the transfer function of the decoupled closed-loop system, the necessary and sufficient conditions for simulta neously decoupling, elimination of impulsive behaviour and arbitrary allocation of the poles of the characteristic polynomial of the closed-loop system, and the analytical determination of the poles which are cancelled out in the general form of the transfer function of the closed-loop system. The results derived are applied for the decoupling and pole assignment of a nuclear reactor plant.

DOI:10.1049/ip-d.1991.0077

出版商:IEE    

年代:1991

数据来源: IET

摘要:

In the paper, a unifying approach is presented for the solution of the following five major observer design problems, for both regular and singular systems: the necessary and sufficient conditions for the problem to have a solution, the order of the minimal observer, the general analyt ical expressions for the observer matrices, the properties of the closed-loop system, and the full order observer.

DOI:10.1049/ip-d.1991.0078

出版商:IEE    

年代:1991

数据来源: IET

摘要:

This paper presents an approach to formulating the optimisation problem of linear discrete-time systems with delays. It is shown that, by properly augmenting the state vector, the optimisation problem of achieving closed-loop poles inside a circular region with centre (β. 0) and radius α, where α + |β| ≤ 1, and at the same time accommodating deterministic disturbances, can be reduced to a standard discrete quadratic regulator problem with no delays. It is also shown that the dynamical feedback controller, which minimises the performance to achieve poles inside a circular region and accommodate disturbances, can be implemented via an auxiliary linear dynamical system. The implementation scheme is effective in many applications.

DOI:10.1049/ip-d.1991.0079

出版商:IEE    

年代:1991

数据来源: IET

摘要:

The paper deals with the analysis of automatic generation control (AGC) of a two-area reheat thermal system considering a variable structure controller (VSC) based on the sliding mode concept. A systematic method is suggested for obtaining switching hyperplanes. Optimum gain settings of the variable structure controller are obtained, both in the unconstrained (neglecting generation rate) and the constrained (considering generation rate constraint) modes, using the integral squared error (ISE) technique. Investigation reveals that there is a significant improvement in system dynamic performance with a VSC over that with an integral controller. Moreover, the variable structure controller is found to be quite insensitive to wide variations of system parameters.

DOI:10.1049/ip-d.1991.0080

出版商:IEE    

年代:1991

数据来源: IET