Said Mammar

• University of Évry Val d'Essonne

This paper proposes an Active Fault Tolerant Control (AFTC) framework for a quadcopter Unmanned Aerial Vehicle (UAV). The proposed framework is capable of achieving trajectory tracking, estimating states, as well as estimating and compensating for all four actuators multiplicative faults. The framework combines two optimization-based nonlinear esti...

In this paper, an active fault tolerant control (AFTC) framework is presented, with the ability to automatically estimate and compensate for the Loss Of Effectiveness (LOE) of all actuators of a quadcopter Unmanned Air Vehicle (UAV), while achieving trajectory tracking. The aforementioned AFTC framework consists of a reconfigurable controller based...

This paper presents an Unknown Input Observer (UIO) for a class of Lipschitz nonlinear systems affected by disturbances/faults and having slow internal dynamics after the decoupling of the Unknown Input (UI). Thanks to the Asymptotic Decoupling notion, the constraint related to the internal dynamics is bypassed. The nonlinear UIO presents time vary...

In this paper, a Linear Parameter Varying (LPV) Unknown Input Observer (UIO) design for the attitude subsystem of a mass-varying quadcopter is proposed by using algebraic matrix manipulation. First, the design of UIO for LPV systems is discussed. Then, by applying the design process of UIO for the general LPV system, an LPV UIO is designed for the...

This paper concerns the problem of attitude/altitude control of a quadrotor. The main contribution consists of developing a simple Linear Parameter Varying (LPV) model which includes the motor dynamics, weight, and moment of inertia variations. In addition, a robust LPV H ∞ state-feedback controller is proposed. It allows us to perform both a refer...

The contribution of this work focuses on generating the best path for an UAV to distribute medicine to all the infected areas of an agriculture environment which contains non-convex obstacles, pest-free areas and pests-ridden areas. The algorithm for generating this trajectory can save the working time and the amount of medicine to be distributed t...

This paper presents a new set-membership estimation methodology for uncertain switched LPV discrete-time systems subject to unknown inputs, unmeasurable time-varying parameters and measurement noise. The proposed approach provides a guaranteed interval that is constructed as the sum of punctual state estimation and its corresponding estimation erro...

This work is devoted to the problem of guaranteed set-membership state estimation based on zonotopes for discrete-time switched systems with bounded uncertainties and unknown inputs. The additive uncertainties in this contribution are treated using the so called Wi-Radius. The size of the zonotope which contains the real system state is decreased a...

This paper proposes a robust model based observer for actuators fault detection and diagnosis (FDD), applied to an unmanned aerial vehicle: quadrotor. The observer is designed aiming at maximizing the fault to residual sensitivity by using the $H_{-}$ index properties, and minimizing the$H_{\infty}$ norm for worst case exogenous signals attenuation...

For many practical applications, it is necessary to design controllers that are, one the one hand, robust against bounded uncertainty in selected parameters and external disturbances. On the other hand, it is also quite common for such systems, that state constraints need to be accounted for which must not be exceeded for any possible parameter val...

This paper addresses a new observer structure and its corresponding design for LTI discrete-time systems affected by Unknown Inputs (UI). We show that the performances of standard UIO can be enhanced, especially, in the presence of stable invariant zeros with slow dynamics (detectable systems). Under mild condition, the proposed UIO design avoids t...

This paper is concerned with the robust passive fault detection problem for switched continuous-time linear parameter-varying systems with mensurable and unmeasurable scheduling parameters. A switched Takagi-Sugeno (TS) interval observer is designed to estimate the set of admissible state values. Using Multiple Fuzzy ISS-Lyapunov function and Avera...

This note presents a new Unknown Input Observer (UIO) with adjustable performances for linear systems. It focuses on state estimation in the presence of zeros with slow dynamics. It is known that if the system has stable invariant zeros and satisfies the decoupling condition then a UIO exists. However, the invariant zeros constrain the pole placeme...

This paper concerns both state estimation and parameters identification for linear system with unmatched unknown parts. It deals with a full order output delayed unknown inputs observer (DUIO), in which, the time delay concept is investigated to define a new augmented dynamic system including delayed state and output vectors. This estimation approa...

This paper presents a hybrid robust control strategy to solve the trajectory tracking function of a quadcopter with time-varying mass. In the context of this paper, two ways of changing the mass of a quadcopter are considered. The first one involves a gradual continuous reduction of the mass throughout the flying time, and the second involves an ab...

This paper investigates the problem of robust state estimation and unknown input interval reconstruction for uncertain switched linear systems. Parameters uncertainty are supposed to be provided with known bounded compact set. A design method for obtaining interval observers that provide guaranteed lower and upper bounds of the state and unknown in...

The place of driving assistance systems is currently increasing drastically for road vehicles. Paving the road to the fully autonomous vehicle, the drive-by-wire technology could improve the potential of the vehicle control. The implementation of these new embedded systems is still limited, mainly for reliability reasons, thus requiring the develop...

In this paper, a new strategy to cope with unmeasurable premise variables in observer design for Takagi-Sugeno (TS) models is proposed. The guiding principles are the immersion techniques and auxiliary dynamics generation, allowing to immerge a given TS system with unmeasured state dependent weighting functions into a larger TS system with weightin...

This paper presents a trajectory generation method for the automatic parallel parking. In the first place, a continuouscurvature path satisfying geometric constraints is generated. During the automated tracking of the trajectory, following errors might appear. Then, if necessary, a new trajectory is generated to correct these errors. The regenerati...

In this paper the design of observer under the presence of unknown inputs for linear parameters varying transportation systems is considered. The main idea consists in getting a set of conditions to design an observer, which estimates a part of the motorcycle dynamics states independently of some inputs (rider torque) and/or other states (zeros dyn...

In this brief, a robust braking controller is proposed for motorcycles. Its aim is to control both longitudinal slips of the vehicle to optimal ones using a sliding mode controller. The robustness of this controller is proved with respect to change of road adherence, load transfer, and lateral movements. The optimal target slip is computed thanks t...

In this paper, a nonlinear observer is designed in order to estimate the lateral dynamics of motorcycles. A nonlinear model of motorcycle's lateral dynamics is considered and is transformed in a Takagi-Sugeno (TS) exact form. An unknown input (UI) nonlinear observer is then designed in order to reconstruct the state variables whatever the forward v...

With the development of the embedded application and driving assistance systems, it becomes relevant to develop parallel mechanisms in order to check and to diagnose these new systems. This is particularly true in the case of partially and fully autonomous vehicles. In this paper, we focus our researches on a subpart of this issue dedicated to the...

IFAC Safeprocess 2015, 9th International Symposium on Fault Detection, Supervision and Safety for Technical Processes, Paris, France, 02-/09/2015 - 04/09/2015

A robust observer is presented in this paper to estimate the longitudinal tire-road forces, the engine and braking torques for powered two-wheeled vehicles. A study of detectability of the longitudinal dynamics is presented and the tire-road longitudinal forces are estimated using an unknown input observer without any knowledge of tire parameters....

This paper is dedicated to the design of unknown input observers for Linear Parameter Varying systems (LPV) using algebraic matrix manipulation. Firstly, a discussion is provided concerning the classical design approach which requires the matching condition. This condition is satisfied for a class of systems having relative degree one. Secondly, fo...

Most of the wafer fabrication processes are chemical processes, and wafers are traditionally processed in batches for high throughput. One of the important innovations in semiconductor fabrication is the adoption of single-wafer processing by using cluster tools. Each cluster tool integrates several processing modules (PMs) within a closed environm...

There exist many variants of facility location problems. This chapter discusses some most recent advances and issues in this field including a capacitated plant location problem with multi commodity flow (CPLPMF), a multi-type transshipment point location problem with multi commodity flow (MTTLMF), a large scale new variant of capacitated clusterin...

This paper investigates a capacitated lane reservation problem with residual capacity. The focus of the problem is to design time-guaranteed paths for a set of transportation tasks via lane reservation with respect to the residual capacity issue. The lane reservation can ensure the time-guaranteed travel but has negative impact on the normal traffi...

This paper focuses on the implementation on a test vehicle of a tire slip rate controller, based on fuzzy logic method. The slip rate is controlled by regulating the braking pressure on each wheel via an ESP hydraulic unit. The slip rate is estimated via a vehicle velocity observer. Simulation and experimental results show that the tire slip rates...

This paper addresses the problem of lateral dynamics estimation of a vehicle and critical situations detection. For this purpose, two cascaded unknown input observers are designed which achieve finite time convergence. The system describing the lateral vehicle dynamics is decomposed into two sub-systems which are described with linear parameter var...

In this work, two high order sliding mode observers under cascade form are proposed in order to estimate the important states and inputs affecting the lateral dynamics of two-wheeled vehicles. The first observer is based on a vision system and is used to estimate the lateral velocity of the vehicle. This velocity is considered as an additional meas...

This paper investigates the use of algebraic estimators for numerical filtering and derivation applications. After giving some explanations for the choice of the estimator order, we focus on the order one. The frequency and time responses are compared with standard filtering and derivation methods, including the Kalman filter. These estimators are...

This paper presents the design and practical implementation of a lane departure avoidance assistance for passenger vehicles based on a state feedback dynamic controller. The road curvature is taken into account as an internal model to ensure convergence of the lateral offset to zero at steady state, even on curvy roads. Lyapunov theory and bilinear...

This brief presents a contribution to nonlinear observer design for both the estimation of vehicle lateral dynamics and road curvature. The latter is recovered by a simple algebraic technique and high-order sliding mode differentiator, which allows to estimate exactly the time derivatives of measured signals. For the lateral dynamics of the vehicle...

This paper considers the integrated control for driver assistance during lane keeping and obstacle avoidance maneuver. The proposed approach handles the driver activity, namely the torque, in order to provide progressive assistance intrusion. The design method allows addressing both underloaded and obverloaded situations. The model formulation uses...

The preventive warning systems are seen as an alternative to rider assistance and risk reduction for Powered Two Wheeled (PTW) vehicles. In this work we propose an analysis of the critical lean dynamics of motorcycle based on a model of double inverted pendulum (DIP). The choice of this structure is motivated by its simplicity and that the model co...

The present article deals with an observer design for nonlinear vehicle lateral dynamics. The contributions of the article concern the nonconsideration of any force model and the consideration that the longitudinal velocity is time varying, which is more realistic than the assumption that it is constant. The vehicle model is then represented by an...

This paper investigates an optimal lane reservation problem with dynamic link travel times via a lane reservation strategy. This strategy is to select some existing general-purpose lanes from a transportation network and convert them to reserved lanes for some special road users only so that a time-guaranteed transportation can be ensured. However,...

The present work deals with the observer based-controller design for nonlinear Powered Two-Wheelers Vehicles (PTW) modeled in Takagi-Sugeno fuzzy representation. Based on the Lyapunov method and Linear Matrix Inequality (LMI) formulation, sufficient conditions have been derived to prove the Input to State Stability (ISS) property of the nonlinear P...

This paper adressed the problem of state and road adhesion estimation by using the Takagi-Sugeno (TS) approach. A Lateral vehicle model is used with nonlinear contact forces. From the considered model an exact TS model with unmeasured premise variables is deduced by the well known sector nonlinearity transformation. In this model, the road adhesion...

This paper considers the integrated control of a three highly cooperative vehicles which follow a leader. The leading vehicle can be driven manually and his longitudinal acceleration is not accessible for the followers. Otherwise each vehicle of the string uses front and rear information to achieve speed and reference distance tracking. Thanks to t...

This article presents the design of a lane departure avoidance system which is conceived to operate even in demanding manoeuvres with respect to the lateral vehicle dynamics. Piecewise affine state feedback and output feedback controllers are used to handle the nonlinear behaviour of the lateral tyre forces. The controllers are designed based on th...

In this paper, a nonlinear motorcycle model is considered in order to estimate both the lean and steering dynamics. The model is transformed into a Takagi-Sugeno (T-S) form using the well-known sector nonlinearity approach. The first contribution of this work is the exactness of the obtained T-S model compared to the considered nonlinear model, whe...

Recent advances towards steer-by-wire technology have promised significant improvements in vehicle handling performance and safety. This technology inspired from aeronautics, consists in replacing the traditional mechanical linkages and/or hydraulic power assist with electrical equivalents. This paper describes the adopted approach for development...

The process of an oil refinery contains both discrete event and continuous variables and can be characterized as a hybrid system. It is extremely challenging to schedule such a system. The short-term scheduling problem of crude oil operations addressed in this chapter is one of the most difficult parts. With jobs to be scheduled being unknown at th...

This paper investigates an automated truck transportation problem via lane reservation strategy. The focus of the problem is to design lane reservation based paths for time-efficient transportation. The lane reservation strategy requires to select some existing general-purpose lanes from a transportation network and convert them to automated truck...

In this paper, the problem of observer design for nonlinear Lipschitz systems is treated. An emphasis is put on maximizing the admissible Lipschitz constant for which the observer design is possible. This problem is tackled using a Takagi-Sugeno modeling approach. The idea is to re-write the state estimation error dynamics as an autonomous Takagi-S...

The problem of observer design for nonlinear Lipschitz systems is dealt with in this work. An emphasis is put on the maximization of the admissible Lipschitz constant for which the observer design is possible. This problem is tackled using a Takagi-Sugeno modeling approach. The idea is to rewrite the state estimation error dynamics as an autonomous...

Résumé Dans ce papier, le problème de l'estimation de la dynamique latérale de véhicules à deux roues motorisés est traité. La contribution réside dans la proposition d'une approche d'estimation basée sur un observateur non-linéaire. Dans un premier temps, un modèle de type Takagi-Sugeno (T-S) est proposé en utilisant les transformations par secteu...

The work developed in this paper is realized within the ecoDriver EU FP7 project that is shortly presented in the first part of the paper. Among the several main objectives underlined by this project, one consists in developing a vehicle and energy consumption model to be validated and then used to help the driver to better drive in terms of consum...