A DECOMSYS based tool-chain for analyzing FlexRay based automotive control applications

Abstract

It is now widely believed that FlexRay will emerge as predominant protocol for in-vehicle automotive communication systems. As a result, there has been a lot of recent interest in timing and predictability analysis techniques that are specifically targeted towards FlexRay based electronic control units (ECU) networks. In this work, the DECOMSYS tool [1] is used for mapping the tasks on different ECUs, configuring the scheduling policy used at each ECU, and specifying the FlexRay parameters (e.g. slot sizes and message priorities). The overall system requirements are simulated by flashing such FlexRay based ECU network specifications into the DECOMSYS node. The design tools such as DECOMSYS mostly rely on simulations. As a result, they are time-consuming to use and unable to provide formal performance guarantees, which are important in the automotive domain. In our previous works, we have proposed a Real-Time Calculus (RTC) based compositional performance analysis framework for an ECU network that communicates via FlexRay bus [2]. The RTC based framework allows computation of performance analysis parameters such as the maximum end-to-end delay experienced by any message, the amount of buffer required at each communication controller and the utilization of the different ECUs and the bus. In this paper, we have plugged in the RTC based framework into the DECOMSYS tool. The combined setup consisting of DECMSYS and RTC based framework can be utilized to obtain hard performance guarantees, which can then be cross-validated using simulation.