Abstract: This paper proposes an high-gain observer design technique for fault detection in a hydraulic pipeline. A general nonlinear model of a pipeline is first derived based on general conditions. Then the observer is designed based on the general nonlinear model without linearisation. Simulation results show that the proposed technique can detect leaks quickly and accurately, compared with ...

This paper aims to study the existence of a change of coordinates which permits to transform a class of nonlinear dynamical systems into the so-called nonlinear observer canonical form. Moreover, an algorithm used to construct such a change of coordinates is given. Based on this form, we can design an observer with a linear error dynamic. This paper is motivated by the results obtained by Krene...

This paper is concerned with actuator fault detection in nonlinear systems in the presence of disturbances. A nonlinear unknown input observer is designed and the output estimation error is used as a residual for fault detection. To deal with the problem of high Lipschitz constants, a modified mean-value theorem is used to express the nonlinear error dynamics as a convex combination of known ma...

This paper presents the problem of nonlinear observer design for a class of time-delay nonlinear systems with uncertainty. The nonlinearity of this class of systems has to satisfy the Lipschitz condition whilst the uncertain term is a bounded function. Various performance indices are analysed to test the stability of the error system when all nonlinear terms satisfying the Lipschitz condition. ...

This paper introduces a methodology for differential nonlinear stability analysis using contraction theory (Lohmiller and Slotine, 1998). The methodology includes four distinct steps: the descriptions of two systems to be compared (the plant and the observer in the case of observer convergence analysis, the plant and the controller in the case of tracking controller analysis), the definition of...

A large class of nonlinear systems can be well approximated by Takagi-Sugeno fuzzy models, for which methods and algorithms have been developed to analyze their stability and to design observers and controllers. However, results obtained for Takagi-Sugeno fuzzy models are in general not directly applicable to the original nonlinear system. In this paper, we investigate what conclusions can be d...

The paper is concerned with the synchronization problem of a general class of multi-input multi-output (MIMO) nonlinear continuous-time systems under sampled-data output feedback control. The main contributions of the present paper are twofold: (i) we provide a unified synthesis method and synchronization criteria for MIMO Lipschitz nonlinear continuous-time systems; (ii) we present a systemati...

— This paper studies the use of control contraction metrics in the solution of several problems in nonlinear control. We discuss integrability conditions of controls and give concrete results for mechanical systems. We also study the relationship between existence of a metric and differential L 2 gain, a form of differential dissipativity, and the use of convex optimization for robust stabiliza...

The output behavior of a nonlinear control system depends not only on its input but also on its initial conditions. These two factors have to be considered simultaneously in nonlinear systems design. This paper presents a new definition, called dynamic right factorization, for nonlinear dynamic control systems. This factorization takes the initial conditions as well as the system input into acc...