FlexRay容錯系統之可靠性排程

Reliability Scheduling Approach for FlexRay Fault-tolerant Systems

洪宗華(Zong-Hua Hong)

指導教授 ： 李宗演

國立臺北科技大學/電資學院/電腦與通訊研究所/碩士(2014年)

摘要

時代的變遷，汽車逐漸轉向電子化自動化的模式，為了滿足節能、安全、舒適，更或者是智慧型的汽車，開始運用大量的電子控制器(ECU)與車內佈線，造成維修困難以及成本的上升，因此發展出車用網路(FlexRay、CAN、LIN)，以提升ECU之間的傳輸速度、穩定度以及連結數量。針對電傳線控 (x-by-wire)的應用，FlexRay能夠滿足即時、高速、精確控制、容錯等等的需求。對於Safety-Critical系統的即時性能與可靠性考量，目前有許多研究在FlexRay上提出各種容錯的方法或技術。本研究以C語言實現了FlexRay通訊框架，並於FlexRay靜態段中提出一個可靠性排程演算法透過重新傳送訊息去增加系統的可靠性與最小化slot的使用數量。實驗結果顯示我們所提出的可靠性排程演算法(RSA)可以有效減少平均19.83%的執行時間、3.21%的slot的使用數量、15.24%的訊息可排程性。

關鍵字

車用網路 ； 排程演算法 ； 靜態段 ； 可靠性 ； 重傳訊息 ； 容錯

並列摘要

In the recently, the automotive gradually transform into auto electronic system. In order to ensure the energy saving, safe, comfortable and intelligence, the automobile of number of ECU and cable are consistently increasing. It has resulted in maintenance difficult and cost increased. Therefore, the automotive network is developed to improve transmission speed, stability and number of connection for ECU. The FlexRay can satisfy real-time, high-speed, precise control and fault tolerance of features in automotive network for x-by-wire automotive applications. Considering real-time and reliability for Safety-Critical system, the most of the researches are based on FlexRay with various fault-tolerant approaches or technology. In this work, a FlexRay framework has been implemented by C++ language and the reliability scheduling algorithm (RSA) is presented to increase the reliability of system by re-transmitting messages in the static segment of FlexRay as well as minimize number of slot used. The simulation results show that the proposed RSA algorithm can reduce 19.83% on execution time and 3.21% on slots used. The system schedulability can reduce 15.24%.

並列關鍵字

FlexRay ； Fault-Tolerant ； Static Segment ； Scheduling Algorithm ； Re-transmitting Messages

參考文獻

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[5]B. Tanasa, U. D. Bordoloi, P. Eles, and P. Zebo, “Scheduling for Fault-Tolerant Communication on the Static Segment of FlexRay,” in Proceedings of 2010 IEEE 31st Real-Time Systems Symposium (RTSS), 2010, pp. 385-394.

[6]Wikipedia, ”Real-time operating system”

[7]Shan Ding, “Scheduling approach for static segment using hybrid genetic algorithm in FlexRay systems,” in Proceedings of 2010 IEEE 10th International Conference on Computer and Information Technology (CIT), 2010, pp. 2355-2360.

[8]K. Schmidt and E. G. Schmidt, “Message scheduling for the FlexRay protocol: the static segment,” IEEE Transactions on Vehicular Technology, 58(5), pp. 2170-2179, 2009.