The increasing use of electronic components in today&rsquo / s automobiles demands more powerful in-vehicle network communication protocols. FlexRay protocol, which is expected be the de-facto standard in the near future, is a deterministic, fault tolerant and fast protocol designed for in vehicle communication. In the near future, safety critical X-by-Wire applications will be available in the automobiles and FlexRay networks can be used to provide communication for the Electronic Control Units (ECUs) that perform related functions of X-by-Wire applications. In this thesis the performance of the FlexRay networks with various communication scenarios is evaluated in a real time environment and the results are presented. Communication scenarios investigate both static and dynamic segment of the FlexRay and allow evaluating the capabilities of the protocol. Several performance metrics such as utilization, static slot allocation, jitter are defined for the evaluation of the results.

L'introduction des systèmes embarqués dans l'automobile à commandes électriques (X-by-Wire) pose des problèmes nouveaux et spécifiques pour la tenue des exigences de sûreté de fonctionnement. En effet, ils sont dépourvus de la redondance mécanique (barre de direction, circuit hydraulique...) capable d'offrir un service minimum en cas de dysfonctionnement important de l'électronique. Ces systèmes largement distribués sont particulièrement sensibles aux perturbations d'ordre électromagnétique, et chaque faute transitoire peut éventuellement être la cause d'une défaillance catastrophique.<br />Dans ce contexte, le travail présenté ici est d'ordre méthodologique. En particulier, nous proposons une méthode de vérification des contraintes temps réel en mode nominal (mode non perturbé), et une méthode de prévision quantitative de fautes (mode perturbé) dont l'objectif est de mesurer l'influence des fautes transitoires liées à l'environnement et des performances temps réel du système sur la sûreté (probabilité d'occurrences de défaillances catastrophiques par zone perturbée) de ce même système. Nos travaux ont été appliqués sur les systèmes de direction Steer-by-Wire, mais les méthodes d'évaluation proposées sont génériques. Pour l'instant, seule des préconisations internes aux entreprises sont ciblées. Ainsi, une exigence dont la garantie devrait être prouvée est, par exemple : la probabilité de défaillance catastrophique doit être inférieure à 1.10-9 par heure de fonctionnement. Grâce à la méthode que nous avons développée, cette garantie sera alors complétée par l'évaluation de la fiabilité comportementale du système. Fournissant des résultats quantitatifs, cette technique permet de réaliser plusieurs études de sensitivité, comme, par exemple, l'influence de la durée du cycle de communication sur un protocole de communication de type TDMA (Time Division Multiple Access), l'influence de la diversification dans la redondance des sous-systèmes, ou encore l'influence d'un mécanisme de tolérance aux fautes proposé par TTP/C et FlexRay.

<p>The purpose of this master thesis project has been to analyze and document the Sirius 2001 Concept Car. In addition, it has also been a goal to get the car in a usable state by implementing new software on the on board computers. </p><p>The car is a Tiger Cat E1 that is modified with four wheel steering and an advanced X-by-Wire system. The computers in the X-by-Wire system consist of six TTP PowerNodes that communicate with each other over a redundant, fault tolerant TTP/C communications bus. The computers are connected to a number of sensors and actuators to be able to control the car. </p><p>This project has contributed to the car in several ways. A complete documentation of the systems implemented in the car is one. Another is a programmers manual which significantly lowers the threshold when working with the car. Last but not least is the modifications in hardware and software, which have made the car usable and show some of the possibilities with the system. </p><p>The results show that the Sirius 2001 Concept Car is a suitable platform for research in car dynamics and fault tolerant systems. The work has also shown that the TTP/C communication model works well in an application like this.</p>

The purpose of this master thesis project has been to analyze and document the Sirius 2001 Concept Car. In addition, it has also been a goal to get the car in a usable state by implementing new software on the on board computers. The car is a Tiger Cat E1 that is modified with four wheel steering and an advanced X-by-Wire system. The computers in the X-by-Wire system consist of six TTP PowerNodes that communicate with each other over a redundant, fault tolerant TTP/C communications bus. The computers are connected to a number of sensors and actuators to be able to control the car. This project has contributed to the car in several ways. A complete documentation of the systems implemented in the car is one. Another is a programmers manual which significantly lowers the threshold when working with the car. Last but not least is the modifications in hardware and software, which have made the car usable and show some of the possibilities with the system. The results show that the Sirius 2001 Concept Car is a suitable platform for research in car dynamics and fault tolerant systems. The work has also shown that the TTP/C communication model works well in an application like this.