Winter 2005-2006

Modélisation et digitalisation d’une boucle de mesure de courant utilisant un capteur de type flux-gate

/webdav/site/la/users/139973/public/photo-project/LEM1.gif La mesure de courant est une technique délicate dont l’entreprise LEM est un leader au niveau international. Le principe de base est de mesurer par méthode différentielle (i.e. incluant une boucle de rétroaction pour désensibiliser la mesure) une variation de champ magnétique induite par le courant à mesurer. La mesure est obtenue par un capteur situé dans un circuit magnétique canalisant le flux. Traditionnellement, de tels capteurs exploitent l’effet Hall. Toutefois, des performances supérieures peuvent être obtenues à l’aide de capteurs de type “Flux-gate” qui consistent a utiliser l’effet de saturation du noyau d’une bobine (petite inductance remplacant le capteur a effet Hall). Afin d’extraire l’information sur le courant à mesurer, un schéma en boucle de rétroaction est utilisé. L’effet non linéaire de la saturation est très important pour obtenir des résultats performants. Il s’agit dans ce projet d’établir un modèle de simulation de type Simulink d’un tel système et d’en étudier les propriétés. La digitalisation d’une partie de la boucle sera également explorée ainsi que les problèmes de quantification sous-jacents. Une attention particulière sera portée à l’atténuation du bruit  par des moyens de filtrage numérique. Le nombre de bits de la numérisation devra être établi.

Ce projet est proposé en collaboration avec l’entreprise LEM à Genève.

Professor: Roland Longchamp
Type of project: Semestre
Assistant: Philippe Mullhaupt
Student: Selim Megzari

Nonlinear control of the toycopter

/webdav/site/la/users/139973/public/photo-project/toycopter2.png The Toycopter is a setup closely resembling a helicopter. The principal difference lies in the manner in which the aerodynamical lift is changed. For the Toycopter, the propeller velocities are changed so as to vary the aerodynamical lift. The main drawback is that classical robotic control strategies are unsuited, since they have the tendency of inverting the input-output behavior, thus resulting in unstable dynamics. Moreover, the presence of strong inertial couplings together with the influence of gravity depending upon the vertical coordinate makes the control task difficult.

The aim of this project is to study various choices of outputs, for designing a nonlinear feedback control law. In particular, particular attention will be paid to the role of the conjuguate momenta.
The project will be undertaken both in simulation using Matlab and implemented on the available experimental setup.

MER: Denis Gillet
Type of project: Semester
Assistant: Philippe Mullhaupt
Student: Sylvain Rudaz

Distributed hierarchical vehicle control & semi-autonomous collaborative driving

/webdav/site/la/users/139973/public/photo-project/khep-base.jpg The aim of this project is to investigate road-crossing strategies for car platoons composed of two or more vehicles. A path generation and control strategy will be studied using both (i) control design techniques for path tracking and generation, and (ii) game theoretical decision making using multi-players (vehicles) working either collaboratively or non-cooperatively. The importance of the information available will be stressed (sight distance, available data concerning the traffic and the crossroads, etc.). The study will be validated using a platoon of reduced-scale mobile robots.

MER: Denis Gillet
Type of project: Semester
Assistant: Philippe Mullhaupt
Student: Piyawat Kaewkerd

Control of a flying structure

/webdav/site/la/users/139973/public/photo-project/VTOL2.gif The goal of this project is the control of a Vertical Take-Off and Landing (VTOL) structure. The structure is made of four independent propellers, each having its own electrical motor. The sustentation and the position control of the structure is accomplished by manipulating the four motor torques. The control of the VTOL is challenging due to its highly nonlinear dynamics. A dynamic model of the VTOL is available, as well as a novel control approach developed at the Laboratoire d’Automatique. The work to be done as part of this project encompasses:
1. Identification of the mechanical parameters of the VTOL structure,
2. Implementation of the proposed control approach on the experimental setup (implementation in C++).
This project requires some interest in the understanding and implementation of advanced control methods.

Professor: Dominique Bonvin
Type of project: Master
Assistant: Sébastien Gros
Student: Joakim Gunnarsson

La commande d’une moto-solaire

Le but du projet est de concevoir un système de commande de l’équilibre d’une moto solaire. Dans un premier temps, un modèle précis du système devra être étudié. L’étudiant devra déterminer les conditions de faisabilité, choisir les grandeurs de commandes et faire un premier bilan énergétique du système de régulation. Une simulation du système à commander sera ensuite implémentée (sous Matlab) permettant de valider la synthèse du régulateur que l’étudiant aura réalisée. Si le temps le permet, le régulateur sera validé sur un modèle réduit du système à commander.
L’étudiant devra travailler en étroite collaboration avec les membres de l’équipe SUNRAYCING en charge de la mécanique et de l’aérodynamique de la voiture (moto).

Professor: Roland Longchamp
Type of project: Master
Assistant: Hamid Khatibi and Alireza Karimi
Student: Davis Daidie

/webdav/site/la/users/139973/public/photo-project/Spider-Crane.gif In order to improve container transfer rates, the new highly efficient crane “Spider Crane” has been designed and built in the LA. A reduced-order model of Spider crane is also available.

The aim of this project is threefold:
(i) To develop a local closed-loop control for each crane’s motor.
(ii) To integrate these control loops into the global control law that manages the crane behavior.
(iii)Finally, the result will be implemented on the reduced model.
If time is available, aspects like interface development and piloting help will be tackled as well.

Professor: Dominique Bonvin
Type of project: Master
Assistant: Davide Buccieri and Philippe Mullhaupt
Student: Thomas Johansson

Semi-automatic Web Services composition

/webdav/site/la/users/139973/public/photo-project/EmersionLogo.jpg Web Services are software components, which can be accessed over the Internet through their exposed interfaces. The interfaces are described in a machine-interpretable format called Web Service Definition Language (WSDL). Other systems can interact with Web services using Simple Object Access Protocol (SOAP) messages typically conveyed using HTTP. In an eLearning framework where educators would like to integrate Web services easily, it is essential to support the authoring process for non-IT experts. So far, the Sustainable Interaction Systems Group has developed an authoring tool allowing educators to compose classical multimedia components (image, text, structured document, etc.). The goal of this project is to contribute to the extension of this authoring tool to support semi-automatic Web Services composition. (Emersion)

MER: Denis Gillet
Type of project: Master
Assistant: Karim Zeramdini
Status: Nerea Arenaza

SmartFish modeling

/webdav/site/la/users/139973/public/photo-project/smartfish1.gif SmartFish Smartfish is a flying structure that uses a particular low aspect-ratio shape in order to reduce the drag and increase the efficiency at high speed. The maneuverability of SmartFish is also an important issue. In order to minimize the drag associated with the control of SmartFish.

The goal of this project is to build a dynamical model of the SmartFish suited for control. Though advanced aerodynamical models have been proposed by the SmartFish group, yet a dynamic model is required for control. This model will include the inertias of the structure as well as the forces and torques generated by the interaction of the SmartFish with the air. This model will be used in further studies related to the ‘Challenge Smartfish’ project, and is therefore subject to numerous modifications as the structure, masses and shape are to be changed. Hence the model developed should be easy to modify and allow the study of multiple configurations of the system.
Finally, a structure that describes the stability and controlability of the Smartfish will be explored.

MER : Denis Gillet (Philippe Mullhaupt)
Type of project: Semester
Assistant: Sébastien Gros
Student: Alex Vulliemin