The influence of real-time constraints on the design of FlexRay-based systems

This article describes important challenges regarding the design, specification and implementation of FlexRay-based automotive networks. The authors outline a design approach that especially accounts for timing constraints of the network, namely end-to-end and cycle timing constraints. The schedule generation for electronic control units (ECU) as well as bus entities is addressed and constraint compatibility with basic FlexRay configuration properties is investigated. The discussed design approach considers three practical design challenges of the automotive industry: first, the function-based cycle timing constraints and their dependency to basic bus design is presented. Second, the challenge of distributed development of modern on-board networks by many different teams and an approach for collaboration improvement is discussed. Finally, the third part describes the configuration of time-triggered ECU schedules with respect to different constraint types.