在近年來的車用系統中,利用結合時序觸發以及事件觸發通訊的車用通訊協定FlexRay來增加信息的信息分配的可行性以及彈性。 對於汽車業來說,車用系統的安全性以及穩定性是最重要的,因此在設計時必須對信息做時序分析,並且確保其能夠在期限內傳送完畢。因此本論文重點為利用整數線性方程式來對信息做時序分析,此外,FlexRay的規範中允許一種名為間隙分配的機制,此機制在有所限制的設計規範下有助於提高信息整體的可分配性以及為未來可能新增加的信息提供了更多的分配彈性。 此機制在做時序分析時也被考慮進去。
在模擬部分,將提供實際用於車用系統訊號的測試標準代入本篇論文所提出的方法,並也把此測試標準一併代入未考慮間隙分配機制的分析方法,比較兩者結果來說明使用間隙分配機制的好處,另外比較將測試標準在不同位元速度下得到的結果,進而來證明本篇論文所提出方法的合適性,最後計算總線利用率在考慮和不考慮間隙分配機制下的結果,其結果顯示在考慮間隙分配機制下的總線利用率高於不考慮時的利用率。

FlexRay is a communication protocol that combines event- and time-triggered communication to increase the schedulability and flexibility of message scheduling in current car systems. Because safety and reliability are particularly crucial for automotive systems, the response times of signals transmitted by electronic control units must be under their deadlines. Therefore, this study analyzed the timing of messages by using an integer linear program. Furthermore, to increase the bandwidth utilization, the slot-multiplexing (SM) mechanism that is allowable in protocol specification was adopted to schedule messages in the dynamic segment of the FlexRay protocol, and this mechanism was also considered in the timing analysis.
The proposed method was applied to a Society of Automotive Engineers benchmark to ensure that all messages were transmissible. Finally, the improvement in bandwidth was assessed by comparing the bandwidths of the SM and non-SM models.

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