Ensures Ethernet in automotive architectures
Vehicle manufacturers are today presented with big challenges and opportunities. Past growth in sales has been achieved to a large extent by innovations in comfort, with functions like automatic climate control and navigation; safety, such as, for example, vehicle stability control, multiple airbag systems, and seatbelt control; and environmental protection, including direct fuel injection and catalytic converter control.
These innovations have been made possible by the use of embedded electronics. Today, a car has several tens of computers, communicating through data buses in a complex, distributed, in-vehicle electronic architecture. Future functions will be even more complex, distributed, interconnected and necessarily interdependent. Their correct behaviour will not simply be a matter of functional correctness that is, making sure that the results of the computations are correct, but they will depend on timing and reliability constraints.
Building such systems in an efficient, predictable and reliable way in spite of the increased complexity of functions and architectures and managing the supply chain in a way that allows predictable integration of software components and platforms is the future major challenge of the automotive industrial sector.
Precise timing is essential
Many systems today are time-critical or at least time-dependent. The effects of improper timing range from a loss of comfort to life-threatening situations. Vehicle stability control, involving differential braking of individual wheels is an example of a function in which safety depends on the timely delivery of the braking commands. Precise timing and prioritisation of functions are essential for both, safety and comfort.
Presently timing is mostly taken into consideration at late stages of the development process, i.e., during the implementation and integration phase. Timing behaviour is verified by means of measurements at testing time, rather than through formal and systematic analysis accompanying the whole design process. The likely consequences are long and costly design iterations whenever problems are detected.
For this reason, a considerable number of innovative functionalities cannot be implemented in a cost-effective manner, and may therefore not be realised. A predictable development process able to handle timing in all phases and capable of verifying and validating the timing behaviour of a real-time system early in the process is a key factor in bringing new innovative features to market and in handling their implementation complexity.
Time Critical Networks product offering
Time Critical Networks aims at a breakthrough in the area of automotive system timing management by using a common, standardised approach for handling all timing-related information during the development process of Ethernet networks. The complexity, and the cost, of the development cycle is significantly reduced, while reliability is improved.Time Critical Networks and their products support the Timing Augmented Description Language (TADL) and the accompanying methodology that provide
These are fundamental prerequisites to avoid costly delays in vehicle start-of-production dates and, in turn, to assure confidence in the dependability and quality of a given solution. The timing concepts which are indeed specific to the automotive domain, complementing the automotive standards AUTOSAR and EAST-ADL, the new language and methodology for a well-defined exchange of timing information in automotive embedded system development.
Text source (partly): Timing Model – Mastering In-Vehicle Timing Constraints (from ITEA2 project TIMMO)
Automotive White Paper
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