Wyniki 1-2 spośród 2 dla zapytania: authorDesc:"Benatman KOUADRI"

Sliding Mode Control Based on Adaptive Backstepping Approch for a Quadrotor Unmanned Aerial Vehicle

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A sliding mode control based on adaptive backstepping approch, is developped respectively in order to synthesise tracking errors and to ensure Lyapunov stability, handling of all system nonlinearities and desired tracking trajectories. Under ground effects and wind disturbances, the body inertia becomes badly known , and non parametric uncertainties are considered in the system model. Dynamic modelling of quadrotor takes into account the high-order nonholonomic constraints, that are considered here in order to test this new control scheme on a model that takes into account the various physical phenomenas, which can influence the dynamics of a flying structure. Finally simulation results are provided to illustrate the performances of the proposed controller. Streszczenie. Przedstawiono system sterowania ´slizgowego z modulem typu backstepping w zastosowaniu do bezzalogowego pojazdu powietrznego (helikoptera). Zaproponowany system sterowania pozwala na zmniejszenie ble¸du trasy i zapewnia stabilno´s´c z uwzgle¸dnieniem nieliniowo´sci, zmian wiatru i inercji pojazdu. Model dynamiczny uwzglednia ró˙zne mo˙zliwe fizyczne zjawiska. (Sterowanie slizgowe typu adaptacyjny backstepping w zastosowaniu do bezzalogowego pojazdu powietrznego). Keywords: Tuning function, Nonholonomic constraints, Adaptive backstepping, Sliding mode. Słowa kluczowe: Slowa kluczowe: sterowanie ´sliozgowe, helicopter bezzalogowy, backstepping. Introduction Unmanned aerial vehicles are characterized by high level of complexity, high dimension of the state space, multiple inputs and outputs, parametric uncertainty, unmodeled dynamics. Its inertia will slowly vary as a result of wind disturbances and ground effects. We need a control law that adapts itself to such changing conditions. Affected by aerodynamic forces, the Quadrotor dynamics is nonlinear, multivariable, and is subject to parameter uncertainties and external disturbances. In turn, controlling of the Quadrotor [...]

Study of High Frequency Electromagnetic Disturbances Generated by a Rectifier and Chopper Association

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This paper discusses the electromagnetic disturbances generated by a rectifier and a chopper association which is frequently encountered in power electronics. The paper presents the basic principles of electromagnetic interferences in power electronics and an EMC study of the considered device that is namely the rectifier and chopper association. The problems involved in temporal or frequential simulations are highlighted in this study. A comparison between our simulation results and experimental one's taken from literature is also presented in this paper. At the close of this study we recommended the use of EMC filtering to reduce the rectifier and chopper association disturbances at acceptable levels which are specified by EMC standards. The main conclusion of the paper is that this device is really electromagnetic pollutant and must then be taken into account, as a whole, in any study implying this kind of converters. Streszczenie. W artykule analizuj. si. zak.ocenia elektromagnetyczne generowane przez uk.ad prostownika i choppera. Wyniki symulacji porownano z wynikami eksperymentalnymi. Zaproponowano uk.ad filtrowania zak.oce.. (Analiza zak.oce. elektromagnetycznych generowanych przez uk.ad prostownika z chopperem) Keywords: Electromagnetic compatibility (EMC), power electronics, rectifier-chopper association, conducted disturbances, filtering. S.owa kluczowe: kompatybilno.c elektromagnetyczna, zak.ocenia elektromagnetyczne, prostownik. Introduction Today, Electromagnetic Compatibility (EMC) seems to be one of the major constraints of power electronics converters. Unfortunately, it is too often regarded as the last phase of the development of a converter since it represents the last step of its marketing. The estimation of conducted and radiated disturbances by simulation offers a considerable gain from the economic point of view [1], [2]. Indeed, static power converters, such as rectifiers and choppers, operate at increasingly hig[...]

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