• Refine Query
  • Source
  • Publication year
  • to
  • Language
  • 2
  • 1
  • 1
  • 1
  • Tagged with
  • 5
  • 5
  • 5
  • 2
  • 2
  • 1
  • 1
  • 1
  • 1
  • 1
  • 1
  • 1
  • 1
  • 1
  • 1
  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

Méthodologie de développement des services de communication temps-réel d'un intergiciel embarqué dans l'automobile / Design methodology of real-time communication services for an automotive embedded middleware

Santos Marques, Ricardo 14 September 2006 (has links)
Notre objectif est de proposer une méthodologie pour le développement d'un intergiciel embarqué dans l'automobile offrant des services de communication aux applications. Le cadre d'utilisation de nos travaux est la conception de systèmes embarqués dans les véhicules. Ces applications requièrent un intergiciel capable de fournir des services standards de communication, qui cachent la localisation des participants aux échanges, qui masquent l'hétérogénéité des plates-formes de communication, et qui garantissent le respect des contraintes temporelles imposées sur l'échanges et sur l'exécution des participants. La méthodologie proposée vise la conception d'un intergiciel optimisé et pour cela aborde deux aspects : la spécification d'une architecture d'implémentation, et la construction d'une configuration faisable. L'architecture d'implémentation est optimisée dans le sens où l'intergiciel est adapté à l'environnement d'exécution (le système d'exploitation OSEK/VDX OS), et minimise son utilisation des ressources disponibles. Elle apporte une réponse, d'une part, au niveau de la spécification d'une architecture logicielle (construite à l'aide de design patterns ), et, d'autre part, à la manière dont cette architecture est déployée sur une plate-forme concrète (sous la forme d'un ensemble de tâches). La procédure proposée pour la construction de la configuration de l'intergiciel calcule les caractéristiques temporelles faisables de l'intergiciel et des trames émises par les stations d'un réseau CAN. Elle prévoit aussi une étape pour le calcul d'une allocation de priorités faisable pour les tâches de l'application sur chaque station. L'optimalité de la configuration est atteinte en assurant le respect de toutes les contraintes temporelles imposées sur les échanges et sur l'exécution des tâches de l'application et de l'intergiciel. / Our objective is to propose a methodology for the development of an automotive embedded middleware that provides communication services to the applicative level software. This work is focused on the design of automotive functions, where the nowadays context demands a middleware capable of offering standard communication services, hiding the localization of the participants in the exchanges, masking the heterogeneity of communication platforms, and ensuring that the timing constraints imposed on the exchanges and on the execution of the participants are met. The proposed methodology is aimed for the design of an optimised middleware. For this purpose, it deals with two topics: the specification of an implementation architecture, and the construction of a feasible configuration. The implementation architecture is optimised because the middleware is well adapted to its execution environment (operating system OSEK/VDX OS), and minimizes the utilization of the available resources. It contributes, on the one hand, to a specification of a software architecture (built using design patterns), and, on the other hand, to mechanisms allowing to deploy this software architecture onto a concrete platform (under the form of a set of tasks). The algorithm proposed for the construction of a configuration determines feasible timing characteristics for the middleware and for the frames exchanged over a CAN bus. It covers also the calculation of a feasible set of priorities for the applicative tasks executing on each station of the bus. The correctness of the configuration is achieved by ensuring that the timing constraints imposed on the exchanges and on the execution of the applicative and middleware tasks are met.
2

Development of an ISO 26262 ASIL D compliant verification system

Carlsson, Daniel January 2013 (has links)
In 2011 a new functional safety standard for electronic and electrical systems in vehicles waspublished, called ISO 26262. This standard concerns the whole lifecycle of the safety criticalelements used in cars, including the development process of such elements. As the correctnessof the tools used when developing such an element is critical to the safety of the element,the standard includes requirements concerning the software tools used in the development,including verification tools. These requirements mainly specify that a developer of a safetycritical element should provide proof of their confidence in the software tools they are using.One recommended way to gain this confidence is to use tools developed in accordance to a“relevant subset of [ISO 26262]”.This project aims to develop a verification system in accordance to ISO 26262, exploringhow and what specifications should be included in this “relevant subset” of ISO 26262 andto which extent these can be included in their current form. The work concludes with thedevelopment of a single safety element of the verification system, to give an demonstrationof the viability of such a system.
3

A Modeling Methodology for Automotive Embedded System¡GAn MDA Approach with UML

Lin, Chia-Chun 11 July 2012 (has links)
Automotive embedded systems used much in the main body control system. Also because the system needs to meet functional requirement, environment requirement, timing requirement, interface requirement and Failure Mode and Effects Analysis (FMEA) so it is necessary to have an automotive embedded systems modeling methodology. Therefore, this study proposes an automotive embedded systems modeling methodology which combines MDA and UML, and detailed description of the model diagram used by each modeling phase and the diagram modeling method and steps. System development team can be clearly implemented in accordance with the methods and steps for automotive embedded system modeling. The methodology also can be used as the communication standard of the system development team. Systems modeling during system modular can promote module reuse rate in order to enhance the efficiency of system development. The methodology of this study is based on design science research methods, usability evaluation of the modeling methodology is implemented for the modeling of demand for Parking aid control unit, the PIM modeling and code conversion. With prove the availability of this modeling methodology. From the results of the assessment system development team can be based on the methodology of modeling methods and procedures to express the results in line with the needs and systems analysis and design of automotive embedded systems and convert the system operating platform and code.
4

Análises preliminares das potenciais vulnerabilidades em sistemas embarcados automotivos

Souza, Marcelo Pires de January 2017 (has links)
Orientador: Prof. Dr. Jorge Tomioka / Dissertação (mestrado) - Universidade Federal do ABC, Programa de Pós-Graduação em Engenharia Elétrica, 2017. / Atualmente os carros são dotados de complexas redes e protocolos de comunicações, destacam-se como os mais empregados em sistemas embarcados automotivos os protocolos CAN (Controller Area Network), LIN (Local Interconnect Network), MOST (Media Oriented Systems Transport) e FlexRay. Outros componentes como sensores, atuadores, unidade central eletrônica e um sofisticado software embarcado, complementam os sistemas automotivos. Estes sistemas são oriundos de uma rigorosa legislação ambiental que fora imposta nos meados de 1980 nos EUA (Estados Unidos da América) e para atender tal legislação, foram desenvolvidos sistemas de diagnósticos a bordo em veículos, com a principal finalidade de controlar os níveis de emissões de gases. Com o decorrer do tempo e o advento da microeletrônica, cada vez mais os componentes eletrônicos foram absorvidos nos projetos dos veículos, a fim de se atender os novos requisitos de mercado, referentes à eficiência energética, segurança, conforto e conveniência dos ocupantes. Conectividade é uma das tecnologias que vem sendo incorporadas aos veículos mais recentes, destacando-se como as mais utilizadas: GPS (Global Positioning System), USB (Universal Serial Bus), Bluetooth, Wi-Fi (Wireless Fidelity) e acesso à Internet via redes de telefones celulares. Não obstante, apresentam estratégias de segurança computacionais relativamente sensíveis, com diversos tipos de vulnerabilidades, que podem abrir lacunas para intrusos mal intencionados, que por sua vez, podem alterar e apoderar-se dos dados dos veículos. Este trabalho se propõe a fazer uma análise preliminar das vulnerabilidades já catalogadas nos sistemas embarcados automotivos, em que a intrusão se manifesta essencialmente através da porta de diagnósticos a bordo, OBD II (On Board Diagnostics II), presente em todos os veículos comercializados no mercado nacional e internacional. / Currently the cars are equipped with complex networks and communication protocols. CAN (Controller Area Network), LIN (Local Interconnect Network), MOST (Media Oriented Systems Transport) and FlexRay protocols stand out as the most used in automotive embedded systems. Other components such as sensors, actuators, electronic central unit and sophisticated embedded software complement the automotive systems. These systems come from strict environmental legislation that was imposed in the mid-1980s in the United States of America, and in order to comply with such legislation, on-board diagnostics systems have been developed in vehicles with the main purpose of controlling emissions levels of gases. With the passage of time and the advent of microelectronics, electronic components have been increasingly absorbed in vehicle designs in order to meet the new market requirements regarding energy efficiency, safety, comfort and convenience of the drivers and passengers. Connectivity is one of the technologies that has been incorporated into vehicles in the latest vehicular manufactures, such as the most used ones: GPS (Global Positioning System), USB (Universal Serial Bus), Bluetooth, Wi-Fi (Wireless Fidelity) and access to the Internet via mobile phone networks. Nevertheless, they present relatively sensitive computational security strategies with several types of vulnerabilities, which can open gaps for malicious intruders, which in turn can alter and seize vehicle data. This work proposes to make a preliminary analysis of the vulnerabilities already cataloged in the automotive embedded systems, where the intrusion is manifested mainly through the OBD II (On Board Diagnostics II) diagnostics port, present in all the vehicles commercialized in the national and international market
5

Etude du canal de propagation radio pour les systèmes embarqués sans fil automobile / Radio frequency channel modeling in a car for tpms (temperature pressure monitor system)

Cheikh M'hand, Mohamed 28 September 2010 (has links)
Les forts besoins en matière d'économie de carburant, de réduction des coûts de maintenance et de diminution des accidents routiers, ont conduit à la conception et à la commercialisation d'une gamme de systèmes embarqués sans fil, installés dans les véhicules roulants terrestres. Or, il faudra surmonter plusieurs défis techniques pour que les divers bénéfices de ses systèmes se réalisent. Ce mémoire de thèse s'est déroulé au sein de l'entreprise Continental Automotive Systems et les laboratoires LAAS et LAPLACE de Centre National de la Recherche Scientifique. Les travaux ont porté sur le canal de propagation radiofréquence dans l'environnement du véhicule pour le système de surveillance de pression des pneumatiques (TPMS) et le système d'accès sans fil (PASE). Ils se sont répartis entre les expérimentations et des études théoriques visant à présenter des modèles efficaces de l'environnement de propagation, d'évaluer la qualité de communication et de proposer des solutions adaptées aux systèmes embarqués sans fil étudiés. Les résultats de simulation et de mesure montrent que nous pouvons bien cerner les mécanismes de propagation mis en jeu dans l'environnement véhicule, et d'adapter en conséquence les solutions protocolaires et antennaires. / The high potential of accident prevention by using an intelligent tire system can be clearly seen through the different accident analysis. It has been shown that adverse road conditions, tire defects or their combination play an important role in road accidents. Moreover the decrease in the number of fatalities, provided that the entire car fleet is equipped with intelligent tire systems, could be significantly improved by preventing at least 10 % of accidents. This would mean that over 4 000 life’s could be saved every year in European countries. The first part of this thesis presents is the TPM (Tire Pressure Monitoring) System, which corresponds to a wireless radiofrequency transmission between a transmitter module (TX) in each tire of the car and a fixed central receiver (RX). The transmitter, next called "Wheel Unit", is composed with different electronic sensors (temperature, pressure, acceleration...) for the detection of the tire inflation status. The data are collected by the receiver where the different wheel unit frames from each tire is decoded by the control unit. Then a graphical display informs the driver with the required pressure and temperature variations. The second investigated system is the wireless car access, which operate the bilateral link LF /RF, by sending the different commands at 315 MHz or 434 MHz. The signals are related to an electronic code featuring the key to control the vehicle (lock/unlock of doors and the trunk release, start of the engine,…). The automotive PAssive Start and Entry system (PASE) module generates a low frequency wake-up message (at 125 kHz) from the car towards the badge, and a RF challenge signal communicates back from the badge to the car at triggering event. The free radio license frequency of 434MHz is chosen for this study. The RF radio-link budget is a keystone of the overall system reliability: the carrier propagation between the wheel unit and the receiver must be effective whatever the ground composition, whatever the angular position or speed of the wheel unit, for each of the four wheel units. Moreover, the system must be insensitive to RF interferences. The transmission between the wheel units and the receiver is tricky because of the many parameters involved. These environment and operating considerations increase the radio-link budget complexity, and contribute to degrade the global transmission quality of the TPM system. The major parameters that impact the TPMS efficiency: System parameters: the system design affects the transmission performances. The frame structure, the modulation schemes and code lines contribute directly or indirectly to increase the BEP (Bit Error Probability), thus the choice of an efficient system strategy is indispensable for the TPMS. Radiofrequency channel: The car body affects considerably the wave propagation, because the data link is not a line-of-sight, and the channel varies rapidly according to the wheel unit positions and the wave trajectories. So, due to the complex and variable environment, the main characteristics of emitted waves also change in phase and power and it produces both destructive and constructive behaviors. Receiver: generally it can be posed near the metallic structure of the car, so the antenna pattern can be corrupted. RF Source effects. To ensure the good reception of the data transmitted from the sensors, a good knowledge of our wireless radio-link channel is mandatory. Thus, the transmitter part of the system must be properly described: the RF source characterization for TPMS –Tire Pressure Monitoring System- is discussed in this thesis. We proposed in the first part an original approach to characterize the source, from the transmitter antenna to the whole wheel system: thus the influence of each element (lumped antenna + rim + tire) is quantified once embedded in the antenna. Several experimental studies are performed in far and near field conditions for a complete characterization.

Page generated in 0.0647 seconds