On-board software in cars – keeping myriad variants in check

Press Release /

The amount of electronics, software and control devices installed in motor vehicles is growing dramatically, and the move towards electric cars will only strengthen this trend. At the embedded world trade fair in Nuremberg (March 2-4, 2010, Hall 11, Stand 11-101), Fraunhofer will be presenting solutions to help get a grip on the vast array of on-board software.

Today's cars are computers on wheels, each one containing up to 80 embedded computer systems and control units as well as around a gigabyte of software to control the car's components and technical extras, whether they be brake assist systems, CD players or satellite navigation systems. No end to the software boom is in sight. The desire for greater comfort and safety is producing increasingly complex systems. Their smooth interaction is becoming a more and more difficult task. The fact that these components are often from different suppliers with different technical standards means integration of the modules is no easy matter. This is where AUTOSAR (Automotive Open System Architecture), an initiative of various car-industry manufacturers and suppliers founded in 2003, wants to make a difference. To enable seamless integration of the system and software components in cars, the AUTOSAR partners are developing the firstever uniform standard for automobile software.

At embedded world 2010, Fraunhofer will be appearing for the first time as a premium member of the AUTOSAR development partnership. The Fraunhofer Institute for Software and Systems Engineering ISST in Berlin, the Fraunhofer Institute for Open Communication Systems FOKUS in Berlin and the Fraunhofer Research Institution for Communication Systems ESK in Munich are making their expertise available to the AUOTSAR partnership of car and software manufacturers and suppliers in a variety of areas, including system descriptions, diagnosis and automobile operating systems, and testing and quality assurance. They are also driving forward the interchangeability of software components between different vehicle platforms.

Every embedded system has to be individually adapted to suit each vehicle type – and for individual cars such customizing would normally involve a huge amount of time and effort. The fact, for instance, that a customer might not want air conditioning in his Golf GTI,has to be taken into account by the developers from the word go, along with the potential effects of this decision on 80 other control units in the car. This is where the Fraunhofer ISST can help with its aXBench software, which can be used to individually combine the countless number of automobile functions for various car models and variants. The latest version of aXBench offers improved variant management, which provides developers with strategic support in designing the system architecture. As a result, the different choices made by customers can be implemented more easily.

aXBench helps engineers to compare different potential solutions, allowing them to estimate, at a very early stage, the expected size of the code and the time and effort needed for development and testing. »You don't get to grips with variance by retrofitting software with all the parameters you need to cover every possible configuration, « explains Markus Hardt, an engineer at the ISST and official representative of the Fraunhofer-Gesellschaft at AUTOSAR. »On the contrary, variance has been systematically factored in right from the very start.« At the trade fair, researchers will demonstrate how aXBench functions using an interactive model truck.

Making the work of the developers of AUTOSAR software components easier is the objective of researchers at the ESK. On behalf of the BMW Group they have developed DLT (Diagnostic Log and Trace), a module with an integrated transfer protocol and storage format. This enables developers to display information on the status of their AUTOSAR software with the aid of log-and-trace data. »The DLT's uniform interfaces and its standardized transfer protocol and storage format for log-and-trace data makes system integration and software acceptance a breeze,« says Falk Langer, a scientist at the ESK.

To afford passengers the highest levels of safety and comfort, automobile control systems have to reliable. But will they function reliably in accident situations? That is ultimately a question for quality assurance, and one that can be answered with systematic testing procedures and standardized test environments. At embedded world the Fraunhofer FOKUS will be showcasing new technologies for software testing and quality assurance, among them the »TTCN-3 embedded« standard. »TTCN-3 embedded« is designed mainly to support the car industry in testing safety-critical systems, enabling the safer, more efficient and cost-effective design of quality assurance processes for software components. Above and beyond this, the standard offers a systematic, multivendor approach to testing for automobile quality assurance.

The Assessment Studio program is another solution from the Fraunhofer FOKUS that supports developers in creating AUTOSAR-compliant applications for embedded systems. In the same way as editors review their texts for typing errors prior to publishing, developers and engineers also have to check their functional models for compliance with standards if they are to create safe, efficient software. In this context it is essential that the models are correct and consistent. Up till now, modelers have carried out this job manually, but as models grow ever more complex, the manual approach is becoming too error-prone and time-consuming. Assessment Studio handles this task automatically, checking the functional models and related documentation for compliance within a matter of seconds, regardless of the platform used. The program also provides the corresponding rules, such as AUTOSAR, as part of the package. As Tibor Farkas, Project Manager at the FOKUS, comments: »With our program, engineers can be certain that their applications conform with AUTOSAR.«