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A new predictive scheme is proposed for the control of Linear Time Invariant (LTI) systems with a constant and known delay in the input and unknown disturbances. It has been achieved to include disturbances effect in the prediction even though there are completely unknown. The Artstein reduction is then revisited thanks to the computation of this new prediction. An extensive comparison with the standard scheme is presented throughout the article. It is proved that the new scheme leads to feedback controllers that are able to reject perfectly constant disturbances. For time-varying ones, a better attenuation is achieved for a wide range of perturbations and for both linear and nonlinear controllers. A criterion is given to characterize this class of perturbations. Finally, some simulations illustrate the results.

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SUMMARYA new robust high-order sliding mode controller for a class of uncertain minimum-phase single-inputsingle-output (SISO) nonlinear systems is designed. The high-order sliding mode problem is formulated in input-output term and is viewed in uncertain linear context by considering uncertain nonlinear functions as bounded non-structured parametric uncertainties. A sliding manifold is designed in order to ensure finite-time convergence of sliding variable and its high-order time derivatives. The control law allows the establishment of an rth-order sliding mode. This result is extended to multi-input-multi-output (MIMO) systems.

International audienceThis paper presents the control of an electropneumatic system used for moving steering mechanism. This aeronautic application needs a high-precision position control and high bandwidth. The structure of the experimental setup and the benchmark on which controllers are evaluated have been designed in order to precisely check the use of such actuator in aeronautics. Two kinds of controllers are designed: a linear one based on gain scheduling feedback, and two high order sliding mode controllers ensuring finite-time convergence, high accuracy and robustness. Experimental results display feasibility and high performance of each controller and a comparison study is done

International audienceIt is well-known that standard predictive techniques are not very robust to parameter uncertainties and to external disturbances. Furthermore, they require the exact knowledge of the delay. In practice, these constraints are rarely satisfied. In this paper, solutions are presented to allow the use of predictive control in presence of external disturbances, parameter uncertainties and an unknown input delay. First, a recent predictive control method developed to attenuate the effect of external disturbances is shown to be also robust to parameter uncertainties. In addition, a delay estimator is presented to estimate unknown time-varying delays. Theoretical results are widely illustrated through experimental tests on a DC motor

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