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Hybrid approach to design optimisation: preserve accuracy, reduce dimensionality

Mariusz Kamola (2007)

International Journal of Applied Mathematics and Computer Science

The paper proposes a design procedure for the creation of a robust and effective hybrid algorithm, tailored to and capable of carrying out a given design optimisation task. In the course of algorithm creation, a small set of simple optimisation methods is chosen, out of which those performing best will constitute the hybrid algorithm. The simplicity of the method allows implementing ad-hoc modifications if unexpected adverse features of the optimisation problem are found. It is postulated to model...

Infinite-dimensional LMI approach to analysis and synthesis for linear time-delay systems

Kojiro Ikeda, Takehito Azuma, Kenko Uchida (2001)

Kybernetika

This paper considers an analysis and synthesis problem of controllers for linear time-delay systems in the form of delay-dependent memory state feedback, and develops an Linear Matrix Inequality (LMI) approach. First, we present an existence condition and an explicit formula of controllers, which guarantee a prescribed level of L 2 gain of closed loop systems, in terms of infinite-dimensional LMIs. This result is rather general in the sense that it covers, as special cases, some known results for...

Iterative learning control for over-determined under-determined, and ill-conditioned systems

Konstantin Avrachenkov, Richard Longman (2003)

International Journal of Applied Mathematics and Computer Science

This paper studies iterative learning control (ILC) for under-determined and over-determined systems, i.e., systems for which the control action to produce the desired output is not unique, or for which exact tracking of the desired trajectory is not feasible. For both cases we recommend the use of the pseudoinverse or its approximation as a learning operator. The Tikhonov regularization technique is discussed for computing the pseudoinverse to handle numerical instability. It is shown that for...

Linear repetitive process control theory applied to a physical example

Krzysztof Gałkowski, Eric Rogers, Wojciech Paszke, David Owens (2003)

International Journal of Applied Mathematics and Computer Science

In the case of linear dynamics, repetitive processes are a distinct class of 2D linear systems with uses in areas ranging from long-wall coal cutting and metal rolling operations to iterative learning control schemes. The main feature which makes them distinct from other classes of 2D linear systems is that information propagation in one of the two independent directions only occurs over a finite duration. This, in turn, means that a distinct systems theory must be developed for them for onward...

Model following control system with time delays

Dazhong Wang, Shujing Wu, Wei Zhang, Guoqiang Wang, Fei Wu, Shigenori Okubo (2016)

Kybernetika

Design of model following control system (MFCS) for nonlinear system with time delays and disturbances is discussed. In this paper, the method of MFCS will be extended to nonlinear system with time delays. We set the nonlinear part f ( v ( t ) ) of the controlled object as | | f ( v ( t ) ) | | α + β | | v ( t ) | | γ , and show the bounded of internal states by separating the nonlinear part into γ 0 . Some preliminary numerical simulations are provided to demonstrate the effectiveness of the proposed method.

New trends in design of observers for time-delay systems

Olivier Sename (2001)

Kybernetika

This paper presents some recent results about the design of observers for time-delay systems. It is focused on methods that can lead to design some useful observers in practical situations. First the links between observability properties and observers design is emphasized. Then some necessary and sufficient conditions and a method are provided to obtain unknown input observers for time-delay systems. Furthermore some H design using Lyapunov–Krasovskii and Lyapunov–Razumikhin theories are presented...

Non-fragile controllers for a class of time-delay nonlinear systems

Lubomír Bakule, Manuel de la Sen (2009)

Kybernetika

The paper deals with the synthesis of a non-fragile state controller with reduced design complexity for a class of continuous-time nonlinear delayed symmetric composite systems. Additive controller gain perturbations are considered. Both subsystems and interconnections include time-delays. A low-order control design system is first constructed. Then, stabilizing controllers with norm bounded gain uncertainties are designed for the control design system using linear matrix inequalities (LMIs) for...

Nonlinear controller design of a ship autopilot

Mirosław Tomera (2010)

International Journal of Applied Mathematics and Computer Science

The main goal here is to design a proper and efficient controller for a ship autopilot based on the sliding mode control method. A hydrodynamic numerical model of CyberShip II including wave effects is applied to simulate the ship autopilot system by using time domain analysis. To compare the results similar research was conducted with the PD controller, which was adapted to the autopilot system. The differences in simulation results between two controllers are analyzed by a cost function composed...

On an invariant design of feedbacks for bilinear control systems of second order

Vasiliy Belozyorov (2001)

International Journal of Applied Mathematics and Computer Science

The problem of linear feedback design for bilinear control systems guaranteeing their conditional closed-loop stability is considered. It is shown that this problem can be reduced to investigating the conditional stability of solutions of quadratic systems of differential equations depending on parameters of the control law. Sufficient conditions for stability in the cone of a homogeneous quadratic system are obtained. For second-order systems, invariant conditions of conditional asymptotic stability...

On finite time stability with guaranteed cost control of uncertain linear systems

Atif Qayyum, Alfredo Pironti (2018)

Kybernetika

This paper deals with the design of a robust state feedback control law for a class of uncertain linear time varying systems. Uncertainties are assumed to be time varying, in one-block norm bounded form. The proposed state feedback control law guarantees finite time stability and satisfies a given bound for an integral quadratic cost function. The contribution of this paper is to provide a sufficient condition in terms of differential linear matrix inequalities for the existence and the construction...

On nonlinear equivalence and backstepping observer

J. de Leon, I. Souleiman, Alain Glumineau, G. Schreier (2001)

Kybernetika

An observer design based on backstepping approach for a class of state affine systems is proposed. This class of nonlinear systems is determined via a constructive algorithm applied to a general nonlinear Multi Input–Multi Output systems. Some examples are given in order to illustrate the proposed methodology.

On the interaction between theory experiments and simulation in developing practical learning control algorithms

Richard Longman (2003)

International Journal of Applied Mathematics and Computer Science

Iterative learning control (ILC) develops controllers that iteratively adjust the command to a feedback control system in order to converge to zero tracking error following a specific desired trajectory. Unlike optimal control and other control methods, the iterations are made using the real world in place of a computer model. If desired, the learning process can be conducted both in the time domain during each iteration and in repetitions, making ILC a 2D system. Because ILC iterates with the real...

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