Now showing 1 - 10 of 281
  • Publication
    SAHARA - Systematic Approach for Hazard Analysis and Risk Assessment
    ( 2011)
    Kemmann, Sören
    ;
    With the upcoming introduction of ISO DIS 26262 the awareness for safety in automotive systems has relumed. The standard describes a safety process starting with the Item Definition and with a Hazard Analysis and Risk Assessment (H+R). Hazards and their related risks affect all manufacturers in the same way. Hence, a common understanding and appraisal of Hazards should be established in a systematic way. Therefore, comparability, and consistency among H+Rs of different persons, different groups or even different companies should be established. Furthermore, the consistency of the Item Definition, the H+R, and following safety engineering activities has to be assured. The challenge is that H+Rs are solely based on creativity techniques, which produce an informal representation of information (usually an Excel sheet). This makes it hard to impossible to systematically analyse, compare, and reuse H+R results or to ensure the consistency in a holistic safety engineering process without a significant effort. Numerous methods, and techniques for formalisations und structuring of processes and artefacts in safety critical development exist, but most of those deal with challenges arising once a hazard is defined and one is interested in its origin, or its mitigation strategy. The research and practical approaches to support the prerequisite for all the other techniques, the hazard analysis and risk assessment, is still weak. Therefore, SAHARA's goal is to close this gap by providing a more formal and semantically enriched approach for defining hazards and assessing their risks. The condensed information necessary form ISO DIS 26262 point of view is (1) the situation analysis (2) hazard identification and analysis, and (3) a classification of the contributing factors exposure, severity, and controllability, which results in an ASIL assignment for each hazard. SAHARA yields the benefit of producing machine processable artefacts, and therefore enables comparability, consistency, reusability for increasing the confidence, quality, and efficiency of H+Rs.
  • Publication
    Fahrzeug-Umwelt-Vernetzung Adaptive verteilte Diensteplattform
    Um die Anzahl der Verkehrstoten weiter zu reduzieren, werden über konventionelle passive Sicherheitssysteme hinaus Fahrerassistenzsysteme zur aktiven Sicherheit entwickelt. Ein viel versprechender Ansatz ist die drahtlose Vernetzung der Fahrzeuge untereinander und mit ihrer Umgebung. Dabei werden dem Fahrer bzw. dem Fahrzeug unterschiedliche Dienste zur aktiven Sicherheit, Verkehrseffizienz und Infotainment zur Verfügung gestellt. Eine Grundvoraussetzung für die Diensteplattform ist die Selbstbeschreibung der Dienste, deren Anforderungen und der vorhandenen Infrastrukturelemente (Roadside Units), wie unterschiedliche Rechenleistung und Schnittstellenausstattung. Im Rahmen eines Forschungsprojektes wird untersucht, inwiefern unter Berücksichtigung der Anforderungen an die Dienste und der unterschiedlichen Ausstattung der Roadside Units eine optimale Verteilung der Dienste auf die Roadside Units erreicht werden kann. Dabei wird trotz der Einhaltung der Anforderungen an die Dienste die vorhandene heterogene Infrastruktur optimal genutzt.
  • Publication
    Systematische Analyse von Einflussfaktoren auf die Sensorik bei der Umfelderkennung zur Bestimmung kritischer Situationen
    Die vorgeschlagene systematische Analyse basiert auf der Simulation von Signalpropagation durch eine logische Systemarchitektur für ein gegebenes Szenario zur Identifikation von Sensorik-Messwerten mit hohen Unsicherheitswerten. Sensorik-Messwerte mit hohen Unsicherheitswerten, welche für die definierte Funktionalitätrelevant sind, stellen kritische Situationen dar. Diese kritischen Situationen erfordern die Untersuchung möglicher (externer) Einflussfaktoren.
  • Publication
    RT-DESCRIBE: Self-describing components for self-adaptive distributed embedded systems
    ( 2011) ;
    Becker, Klaus
    ;
    Radermacher, Ansgar
    ;
    Gérard, Sébastian
    In this paper the Fraunhofer ESK presents in cooperation with CEA LIST a novel integrated model-driven methodology for developing selfadaptive distributed embedded systems. Software components of the design model are enriched with self-descriptions which provide information at runtime that is necessary for adaptation decisions. Therefore, a new self-x profile and the tool-chain with the essential model transformations are introduced. The iterative development process, including early feedback through an integrated simulation framework, enables an early refinement of the self-adaptive system.
  • Publication
    SafeAdapt - safe adaptive software for fully electric vehicles
    The promising advent of Fully Electric Vehicles (FEVs) also induces a shift towards fully electronic control of existing and new vehicle functions. Hereby, critical functions, such as Brake- and Steer-by-Wire, require sophisticated redundancy solutions to ensure safety. As a result, the overall electric/electronic (E/E) architecture of a vehicle is becoming even more complex and costly. To address the need for safety, reliability and cost efficiency in future FEVs, the development of a novel adaptive architecture to manage complexity through generic, adaptive, and system-wide fault handling is essential. Moreover, to enable this transition, design simplicity, cost efficiency, and energy consumption are especially important elements. Consequently, the SafeAdapt project seeks a holistic approach by comprising the methods, tools, and building blocks needed to design, develop and certify such safety-critical systems for the e-vehicle domain. In detail, a platform core encapsulating the basic adaptation mechanisms for relocating and updating functionalities is developed on basis of AUTOSAR. It serves as foundation for an interoperable and standardised solution for adaptation and fault handling in upcoming automotive networked control systems. In particular, emphasis is laid on functional safety with respect to the ISO26262 standard, wherefore an integrated approach ranging from tool chain support, reference architectures, modelling of system design and networking, up to early validation and verification is derived. To realistically validate these adaptation and redundancy concepts, an e-vehicle prototype with different and partly redundant applications is being developed. Moreover, the presented work outlines the motivation and challenges of future E/E architectures and contributes a technical strategy to overcome those hindrances.
  • Publication
    Integrating safety analyses and component-based design
    ( 2008)
    Domis, Dominik J.
    ;
    In recent years, awareness of how software impacts safety has increased rapidly. Instead of regarding software as a black box, more and more standards demand safety analyses of software architectures and software design. Due to the complexity of software-intensive embedded systems, safety analyses easily become very complex, time consuming, and error prone. To overcome these problems, safety analyses have to be integrated into the complete development process as tightly as possible. This paper introduces an approach to integrating safety analyses into a component-oriented, model-based software engineering approach. The reasons for this are twofold: First, component- and model-based development have already been proven in practical use to handle complexity and reduce effort. Second, they easily support the integration of functional and non-functional properties into design, which can be used to integrate safety analyses.
  • Publication
    Protocol modeling accuracy in VANET simulators
    ( 2017)
    Bittl, Sebastian
    ;
    Vehicular ad hoc networks are about to enter the mass market in upcoming years. High effort for real world field tests leads to high dependency of development and evaluation of such networks on simulations. We compare supported features of common simulation frameworks with current standards and study the performance impact of incomplete standard conformance. We find that a lack of support for data encoding schemes and security functionality may massively affect simulation results. Our findings apply to many well-known simulation frameworks. Proposals to overcome identified weaknesses are provided.
  • Publication
    Einsatz von Skype im Unternehmen
    (Fraunhofer ESK, 2016)
    Gegenstand dieser Studie ist der Internet-Telefoniedienst Skype, der sich grundsätzlich an Endanwender richtet. Im Mittelpunkt steht dabei die Frage, ob und unter welchen Umständen sich dieses Skype-Angebot auch für den Einsatz in Unternehmen eignet. Microsoft bietet darüber hinaus eine Skype-Lösung (ehemals Lync) an, die sich ausdrücklich an Unternehmen wendet. Deren Markenname ist ""Skype for Business"". Dieser Dienst wird in der vorliegenden Studie nicht untersucht; dazu hat das Autorenteam (unter Leitung von Thomas Messerer) eine eigene Kurzstudie verfasst.
  • Publication
    Modellbasierte Validierung von Infotainment-Funktionen im Auto
    ( 2012)
    Paulic, A.
    ;
    Zeller, Marc
    ;
    ;
    Bei der Kaufentscheidung für ein Auto werden Infotainment- und Multimedia-Anwendungen immer wichtiger. Die Netzwektechnologie Media Oriented Systems Transport (MOST) ist derzeit Standard für automobile Infotainment-Systeme und ermöglicht anspruchsvolles Infotainment im Auto. Die zunehmende Komplexität und Interaktion dieser Funktionen ist eine große Herausforderung bei der Entwicklung. Die Qualität der Systeme muss bei stetig zunehmender Funktionalität gewährleistet sein, zudem soll die Entwicklung immer günstiger werden. Hierzu wird modellbasierte Softwareentwicklung bereits erfolgreich eingesetzt. In dieser Arbeit haben wir neue Konzepte zur modellbasierten Validierung von Infotainment-Funktionen entwickelt und umgesetzt. Dabei wurden sog. Referenzmodelle als ausführbare Spezifikationen eingeführt und zur Validierung wiederverwendet.
  • Publication
    TIMON - Hybrid Communication
    ( 2017) ;
    Onieva, Enrique
    Hybrid communication is an important building block for the real-time services developed in the TIMON project. The presentation gives an overview about the communication architecture and network estimation algorithms developed in the project.