摘要:

An algorithm that achieves complete decentralisation of the Kalman filter algorithm amongst the sensing nodes of a multisensor system is preserved. This algorithm does not require any form of central processing facility or centralised communications medium. Each sensing node implements its own local Kalman filter to arrive at a partial decision which it then broadcasts to every other node. Each node then assimilates this received information to arrive at its own local estimate of the system state. The algorithm guarantees that each local estimate thus obtained is identical to the estimate that would be obtained if a conventional, completely centralised, Kalman filter were used. Because there is no single central processing node the algorithm is highly resilient to loss of one or more sensing nodes. The fully decentralised nature ensures that it is ideal for implementation on a parallel processing array, such as a transputer network. The algorithm has been tested using a simulated multiperson pursuitevasion game to check the viability. The algorithm has also been implemented on a transputer based array of cameras to perform tracking of an object moving around a room.

DOI:10.1049/ip-d.1991.0057

出版商:IEE    

年代:1991

数据来源: IET

摘要:

A design method is presented for active noise control (ANC) systems, in a three-dimensional nondispersive (linear) propagation medium with compact broadband noise sources. The design and implementation of the controller as a digital filter with a fixed transfer function is presented and verified through a set of practical experiments. The concept of self-tuning control as a combination of system identification and control is developed within the ANC system framework. Moreover, as required by the application, a supervisory level of control based on a performance criterion is added that automatically activates self-tuning control. The algorithm is implemented on a high-speed digital signal processor and tested on the exhaust noise of a 100 cc motorcycle. The experimental results are presented and compared with those of a system employing a fixed digital filter controller.

DOI:10.1049/ip-d.1991.0058

出版商:IEE    

年代:1991

数据来源: IET

摘要:

A novel technique, directly using artificial neural networks, is proposed for the adaptive control of nonlinear systems. The ability of neural networks to model arbitrary nonlinear functions and their inverses is exploited. The use of nonlinear function inverses raises questions of the existence of the inverse operators. These are investigated and results are given characterising the invertibility of a class of nonlinear dynamical systems. The control structure used is internal model control. It is used to directly incorporate networks modelling the plant and its inverse within the control strategy. The potential of the proposed method is demonstrated by an example.

DOI:10.1049/ip-d.1991.0059

出版商:IEE    

年代:1991

数据来源: IET

摘要:

An integral variable structure controller (IVSC) for robust servotracking is proposed. It comprises an integral controller, which is designed for achieving zero steady-state error under step input, and a variable structure controller (VSC) which is designed for enhancing robustness. A procedure is developed for determining the coefficients of the switching plane and the integral control gain such that the overall closed-loop system has the desired eigenvalues. Furthermore, a modifed proper continuous function is introduced to overcome the chattering problem. An electrohydraulic velocity servocontrol system using the proposed IVSC approach is illustrated. Simulation results show that the proposed IVSC approach can achieve accurate servotracking and is fairly robust to plant parameter variations and external load disturbances.

DOI:10.1049/ip-d.1991.0060

出版商:IEE    

年代:1991

数据来源: IET

摘要:

In the design of identification algorithms, the dead-time is usually modelled by some form of a polynomial function that adequately approximates the dead-time behaviour over relevant frequency bands.The application of all-zero models for approximation of plant dead-times is discussed. Gain-error criterion is established for a general model, whereas phase-error criterion is presented for first-order approximations. It is shown that if a plant transfer function has lowpass features, it is possible to determine a satisfactory all-zero model for the delay.The modelling technique is applied in a recursive least-squares based identification algorithm. This is used to obtain a delay-model predictor. Adaptive controllers, of thek-incremental predictive type, are set up using the identification results.

DOI:10.1049/ip-d.1991.0061

出版商:IEE    

年代:1991

数据来源: IET

摘要:

Using the descriptor standard form, the decoupling problem of the descriptor system by state feedback is studied. The descriptor system is first transformed in controller form and the necessary and sufficient conditions for the descriptor system to be integrator decoupled are obtained. Then, these conditions are shown to be necessary and sufficient for the closed-loop system poles to be assigned while decoupling. The characteristic polynomial of the closed-loop system is explicitly calculated and the conditions for the decoupled system to be internally stable are obtained.

DOI:10.1049/ip-d.1991.0062

出版商:IEE    

年代:1991

数据来源: IET

摘要:

The design of an optimal low-order dynamic controller with α-shift (alpha-shift) for attitude control is attempted for a flexible satellite which is a solar electric propulsion spacecraft (SEPS). The satellite consists of a central rigid body to which two flexible solar panels are attached. The design of a third-order dynamic controller is accomplished using modified linear quadratic Gaussian theory. The improvement in the satellite attitude response with a small uniform α-shift is demonstrated by numerical simulation. A novel concept of block-shift is introduced to move different sets of closed-loop eigenvalues by different amounts. The advantages of this type of block-shift in the design of the controller are shown by simulation. The robustness of the controller with respect to parameter variations is shown to be ample.

DOI:10.1049/ip-d.1991.0063

出版商:IEE    

年代:1991

数据来源: IET

摘要:

The dynamic equations of remotely operated vehicle (ROV) motions in deep water exhibit a highly nonlinear nature. Some of these nonlinearities are simplified for the ease of modelling and only motion in the horizontal plane is considered. A variable structure system (VSS)/sliding mode control (SMC) application is pursued as the control strategy. A variety of parametric selections are made to form this VSS/SMC strategy. An insight is provided into making these choices using a sliding stability argument. A set of digital simulation results are also presented to demonstrate the system behaviour in terms of the parameters of the SMC selected.

DOI:10.1049/ip-d.1991.0064

出版商:IEE    

年代:1991

数据来源: IET

摘要:

An approach to software development for real-time control is presented. The Petri nets formalism is used in the specification phase to describe the concurrency and synchronisation aspects of the software environment. Then the resulting Petri net model is implemented by means of a data driven architecture and can be based on any standard high-level language. The software development procedure described has been followed by a number of users for the rapid production, debugging, testing and prototyping of software modules.

DOI:10.1049/ip-d.1991.0065

出版商:IEE    

年代:1991

数据来源: IET

摘要:

The problem of robust state feedbackH∞control design for a class of linear time-invariant systems with parameter uncertainty in the state space model is investigated. Uncertain systems with time-invariant norm-bounded parameter uncertainty in the state matrix are considered. A state feedback control design which robustly stabilises the plant and guarantees a robustH∞performance for the closed-loop system in the face of parameter uncertainty is presented. It is shown that a suitable stabilising feedback law can be constructed in terms of a positive definite solution to a certain parameter-dependent algebraic Riccati equation.

DOI:10.1049/ip-d.1991.0066

出版商:IEE    

年代:1991

数据来源: IET