Nonlinear Observer

The internship will have as main objective the modeling of  Quadrotor  using the environment Matlab / Simulink . to do this I will concentrate on the principle of flight, then I will attack the control and the stabilization of the drone by using different methods non-linear and robust control that will guarantee the stabilization and good control of the flying drone.
The first part is devoted to the presentation of the adopted model. Then we will demonstrate the algorithms for calculating the set of commands used, all we will make a presentation and analysis of the results of simulations for the purpose of making a comparison between the algorithms of controllers developed in terms of dynamic performance and their ability to stabilize. the system during flight using different trajectories (simple and complex) variations in time and under the effect of possible disturbance. Finally we will detail the equations of a nonlinear observer in sliding mode for the estimation of states of our system.
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Le stage aura comme objectif principal la modélisation d’un drone du type Quadrotor sous l’environnement Matlab/Simulink pour ce faire je vais me concentrer sur le principe de vol, puis je vais attaquer la commande et la stabilisation du drone en utilisant différents types de commande non linéaire et robuste qui va nous garantir la stabilisation et la bonne commande de l’engin volant.

La première partie est consacrée à la présentation du modèle adopté. Ensuite, on démontrera les algorithmes de calcul de l’ensemble des commandes utilisées, toutes on fera une présentation et analyse des résultats des simulations pour le but de faire une comparaison entre les algorithmes des contrôleurs développés en termes de performances dynamiques et leurs capacités à stabiliser le système pendant le vol sous différentes trajectoires (simples et complexes) variantes dans le temps et sous l’effet de perturbation possible. Finalement on détaillera les équations d’un observateur non linéaire en régime glissant pour l’estimation
d’états de notre système.
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Si vous avez des questions sur ce travail, n'hésitez pas à me contacter sur mon adresse mail.
If you have any questions about this project, do not hesitate to contact me on my email address.

e-mail : iliass.elmouderrib@gmail.com

good reading!

Locked brakes and hydroplaning are the reasons which sometimes cause vehicle accidents in wet or icy road surface condition. Anti-lock Braking System (ABS) helps the driver to control decelerating vehicle and improves the control performance of a vehicle in critical conditions. Determining friction of the road surface is essential for developing vehicle control systems such as ABS. Hence, a proper model for modeling road-tire contacts is needed. In order to lessen costs, a minimum number of sensors have been used for determining road friction. In this paper, considering a dynamical model of road-tire contacts, a nonlinear observer has been designed for estimating the road-tire friction force in a vehicle, which only uses the measurement of wheel angular velocity. Finally, the proposed observer is evaluated by comparing its performance with that of the observer designed in a recent work.

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Abstract In this paper, a nonlinearity-compensation control scheme is used in combination with an extended Kalman filter estimation algorithm, in order to ensure AC current shaping and DC voltages regulation for a three-phase three-wire Vienna converter. This approach ...

It is argued that to define social systems as non-biological is to deny their intrinsic biological groundedness which affects their complex system dynamics.  In the case of human social systems, the ecological phenomenon of human society should not be confused with human social organizations as cultural artifacts.

This paper uses second-order sliding mode observers to build up an estimation scheme allowing to identify the tire longitudinal equivalent stiffness and the effective wheel radius using the existing ABS angular sensors. This estimation strategy, based on use of the proposed observer could be used with data acquired experimentally to identify the longitudinal stiffness and effective radius of vehicle tires. The actual results show effectiveness and robustness of the proposed method

Control and state estimation of nonlinear systems satisfying a Lipschitz continuity condition have been important topics in nonlinear system theory for over three decades, resulting in a substantial amount of literature. The main criticism behind this approach, however, has been the restrictive nature of the Lipschitz continuity condition and the conservativeness of the related results. This work deals with an extension to this problem by introducing a more general family of nonlinear functions, namely one-sided Lipschitz functions. The corresponding class of systems is a superset of its well-known Lipschitz counterpart and possesses inherent advantages with respect to conservativeness. In this paper, first the problem of state observer design for this class of systems is established, the challenges are discussed and some analysis-oriented tools are provided. Then, a solution to the observer design problem is proposed in terms of nonlinear matrix inequalities which in turn are converted into numerically efficiently solvable linear matrix inequalities.

In bulk ferroelectric ceramics, extrinsic contributions associated with motion of domain walls and phase boundaries are a significant component of the measured dielectric and piezoelectric response. In thin films, the small grain sizes, substantial residual stresses, and the high concentration of point and line defects change the relative mobility of these boundaries. One of the consequences of this is that thin films typically act as hard piezoelectrics. This paper reviews the literature in this field, emphasizing the difference between the nonlinearities observed in the dielectric and piezoelectric properties of films. The effect of ac field excitation levels, dc bias fields, temperature, and applied mechanical stress are discussed.

This paper designs an observer to estimate the spacecraft’s angular velocity using only Euler angles attitude without
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nonlinear form, and the observability of the nonlinear system is investigated using Lie derivative. The performance of the designed
observer is analyzed and verified using real flight data of Malaysian satellite by employing Extended Kalman Filter algorithm.

In this paper we propose a reduced observer design for aircraft linear velocity estimation based on the measurements of the Euler angles and angular velocity as well as the position which is subject to measurement errors and noise. The observer is designed based on a high gain approach using an output injection, which enables to reduce the order of the observer to six equations rather than a full order observer of order 12. To show the performance of the observer as well as its robustness with respect to measurement errors and noise, a simulation study is carried out using a British aircraft Jetstream-3102 in a real-time virtual simulation platform base on Microsoft Flight Simulator (FS-2004).

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