Advanced Diagnosis for Automotive Communication Systems

Modern car electronics is organized as complex, highly optimized networked systems. This architecture improves the information distribution while minimizing the number of physical connections required. This, in turns, reduces weight and costs and improves car reliability. Evidently, the network plays a central role in maintaining the system in a safe state. The FlexRay communication protocol has been introduced by an industrial consortium to cope with the growing complexity and to support highly dependable systems. This protocol offers a bandwidth 10 times higher than the CAN standard as well as deterministic bus behavior and guaranteed communication delays. FlexRay thus provides more resources for the communication, eases the system integration and supports the development of high-speed control loops. However, the resulting complexity makes the system difficult to manage. The motivation for this work is to gain advanced diagnosis information for FlexRay networks in a non-intrusive way. This advanced diagnosis information comprises the deviation of the nodes oscillators, precision of the system and identification of FlexRay configuration parameters. Measuring these attributes usually requires physical access and hardware or software modification within each single node in the system. One main challenge of this project is to keep the test operation transparent to ensure that the application is not disturbed and can further provide its services. The data gathered can be used for checking the system state and / or to monitor the evolution of the system (e.g. for characterization or identification of components that are about to fail). The information is relevant both for engineers during evaluation and maintenance as well as for online fault detection while designing fault- tolerant systems. This project is a conjoint work between the Austrian Research Center (ARC) and the Virtual Vehicle Competence Center (ViF). ARC will carry its know-how gained during the development of the FlexRay analyzer prototype "BusScope". This platform is especially interesting for intelligent diagnosis due to the availability of low level data (bit stream) for the end user. ViF will provide its expertise for the test of time-triggered communication systems in particular concerning the basic concepts for developing transparent test and diagnosis approaches.

Time-triggered architectures and time-triggered communication systems present a defined behavior both in the time and in the value domain. The precise interface definition provides features such as independent node development, stability of prior services at the node level and constructive integration of the communication system. The aim of this project is to evaluate and enhance existing methods and present new approaches for the remote test of FlexRay networks. More especially, the project goal is to remotely and automatically extract attributes that summarize the current system state. This information can be further presented concisely to the end user (the system know-how is embedded in the prototype) and / or used for advanced error detection. We propose a non-intrusive two steps method for the test of automotive communication systems. During a first step, the system behavior is monitored at different abstraction levels by a dedicated tester node. The traces are analyzed online and the current system behavior is compared to the specification and configuration. During a second step, the dedicated tester node is used to stress the FlexRay clock synchronization algorithm. This patented approach provides further information about quartz frequency of the distributed nodes while being non-intrusive for the system. Hence, normal operation of the network is not endangered and the other nodes do not take notice of this transparent online test. Main outcomes of this project are the following Enhancement of the BusScope platform in order to serve as basis for demonstration and support convergence of the different technologies Integration and evaluation of the online monitoring and remote quartz measurement technologies in the platform in order to illustrate the maturity of the approach Development of test and demonstrator environment in order to evaluate the technology and demonstrate the benefits to possible customers Alignment to ISO 26262 and more especially to dedicated analysis such as FMEA and FMEDA