Extensibility-Aware Message Scheduling Algorithm for the Static Segment of the FlexRay

Recent trends in the automotive industry show increasing demands for the accommodation of function updates and extensions, design uncertainties to reduce the time-to-market and cost. The objective of this paper is to improve extensibility for message schedule of FlexRay from the very beginning of the design, so that it can accommodate the possible future signal size increase that is caused by design uncertainties or function updates. To meet the requirement of industrial domain, the proposed method is AUTOSAR compliant. In this paper, we first introduce an uncertainty model, and define extensibility, extensibility policy and extensibility evaluation indexes. Then, both an optimal integer linear programming-based formulation and a fast heuristic algorithm are proposed as the basic message scheduling algorithms. Finally, a two-step framework extended from the above basic algorithms is constructed to realize the extensibility improvement for message scheduling of FlexRay. Extensive experiments by using a realistic and several synthetic signal sets validate the effectiveness of the proposed algorithms.