Experimental Assessment of the Clique Problem in FlexRay
Martin Horauer, Harald Schuster, Peter Balog · Volume 4: 18th Design for Manufacturing and the Life Cycle Conference; 2013 ASME/IEEE International Conference on Mechatronic and Embedded Systems and Applications · 2013
The FlexRay bus protocol recently adopted by the automotive industry provides both a time- and event-triggered communication paradigm, combined with communication via two independent channels, as well as optional bus-guardians in order to meet the bandwidth and reliability requirements by present and future emerging automotive applications. Despite the benefits and improvements, when compared to traditional bus systems (e.g., CAN), rare faults may still occur. In this regard, this paper presents an experimental investigation of the clique problem, where a FlexRay network gets partitioned into multiple functional domains. In such a scenario the nodes within a domain may still be able to communicate with each other, however, not across domain boundaries. As a result affected applications that rely on information from nodes of either domain may be impaired in their intended functionality as long as such a clique exists. Such an impairment affecting critical applications like the braking system may result in hazardous situations.