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Remarques sur l’observabilité pour l’équation de Laplace

Kim-Dang Phung (2003)

ESAIM: Control, Optimisation and Calculus of Variations

Nous quantifions la propriété de continuation unique pour le laplacien dans un domaine borné quand la condition aux bords est a priori inconnue. Nous établissons une estimation de dépen-dance de type logarithmique suivant la terminologie de John [5]. Les outils utilisés reposent sur les inégalités de Carleman et les techniques des travaux de Robbiano [8, 11]. Aussi, nous déterminons en application de l’inégalité d’observabilité obtenue un coût du contrôle approché pour un problème elliptique modèle....

Remarques sur l'observabilité pour l'équation de Laplace

Kim-Dang Phung (2010)

ESAIM: Control, Optimisation and Calculus of Variations

We consider the Laplace equation in a smooth bounded domain. We prove logarithmic estimates, in the sense of John [5] of solutions on a part of the boundary or of the domain without known boundary conditions. These results are established by employing Carleman estimates and techniques that we borrow from the works of Robbiano [8,11]. Also, we establish an estimate on the cost of an approximate control for an elliptic model equation.

Reproducing kernels and Riccati equations

Harry Dym (2001)

International Journal of Applied Mathematics and Computer Science

The purpose of this paper is to exhibit a connection between the Hermitian solutions of matrix Riccati equations and a class of finite dimensional reproducing kernel Krein spaces. This connection is then exploited to obtain minimal factorizations of rational matrix valued functions that are J-unitary on the imaginary axis in a natural way.

Resolvent estimates in controllability theory and applications to the discrete wave equation

Sylvain Ervedoza (2009)

Journées Équations aux dérivées partielles

We briefly present the difficulties arising when dealing with the controllability of the discrete wave equation, which are, roughly speaking, created by high-frequency spurious waves which do not travel. It is by now well-understood that such spurious waves can be dealt with by applying some convenient filtering technique. However, the scale of frequency in which we can guarantee that none of these non-traveling waves appears is still unknown in general. Though, using Hautus tests, which read the...

Results on existence of solution for an optimal design problem.

Carmen Calvo Jurado, Juan Casado Díaz (2003)

Extracta Mathematicae

In this paper we study a control problem for elliptic nonlinear monotone problems with Dirichlet boundary conditions where the control variables are the coefficients of the equation and the open set where the partial differential problem is studied.

RGB-D terrain perception and dense mapping for legged robots

Dominik Belter, Przemysław Łabecki, Péter Fankhauser, Roland Siegwart (2016)

International Journal of Applied Mathematics and Computer Science

This paper addresses the issues of unstructured terrain modeling for the purpose of navigation with legged robots. We present an improved elevation grid concept adopted to the specific requirements of a small legged robot with limited perceptual capabilities. We propose an extension of the elevation grid update mechanism by incorporating a formal treatment of the spatial uncertainty. Moreover, this paper presents uncertainty models for a structured light RGB-D sensor and a stereo vision camera used...

Robust and nonrobust tracking

Jan Štecha (1998)

Kybernetika

For zero steady state tracking error it is necessary to include n integrators in the control loop in the case of reference signal generated by n integrators. This result can be generalized to arbitrary n unstable modes of the reference generator according to the “internal model principle”. This paper shows an alternative solution of the asymptotic reference signal tracking problem using feedforward. The solution is not robust but gives a feedback controller with reduced complexity. Robust tracking...

Robust and reliable H ∞ output feedback control for linear systems with parameter uncertainty and actuator failure

Chang-Jun Seo, Byung Kook Kim (1999)

Kybernetika

The robust and reliable H ∞ output feedback controller design problem is investigated for uncertain linear systems with actuator failures within a prespecified subset of actuators. The uncertainty considered here is time- varying norm-bounded parameter uncertainty in the state matrix. The output of a faulty actuator is assumed to be any arbitrary energy-bounded signal. An observer-based output feedback controller design is presented which stabilizes the plant and guarantees an H ∞ -norm bound on attenuation...

Robust control of chaos in modified FitzHugh-Nagumo neuron model under external electrical stimulation based on internal model principle

Yuan Jiang, Jiyang Dai (2011)

Kybernetika

This paper treats the question of robust control of chaos in modified FitzHugh-Nagumo neuron model under external electrical stimulation based on internal model principle. We first present the solution of the global robust output regulation problem for output feedback system with nonlinear exosystem. Then we show that the robust control problem for the modified FitzHugh-Nagumo neuron model can be formulated as the global robust output regulation problem and the solvability conditions for the output...

Robust Control of Linear Stochastic Systems with Fully Observable State

Alexander Poznyak, M. Taksar (1996)

Applicationes Mathematicae

We consider a multidimensional linear system with additive inputs (control) and Brownian noise. There is a cost associated with each control. The aim is to minimize the cost. However, we work with the model in which the parameters of the system may change in time and in addition the exact form of these parameters is not known, only intervals within which they vary are given. In the situation where minimization of a functional over the class of admissible controls makes no sense since the value of...

Robust controller design for linear polytopic systems

Vojtech Veselý (2006)

Kybernetika

The paper addresses the problem of the robust output feedback controller design with a guaranteed cost and parameter dependent Lyapunov function for linear continuous time polytopic systems. Two design methods based on improved robust stability conditions are proposed. Numerical examples are given to illustrate the effectiveness of the proposed methods. The obtained results are compared with other three design procedures.

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