單一車道自動公路系統發生意外事故下自動車輛行為模擬

Abstract

世界各國為了解決交通擁擠及其伴隨而至之交通事故、能源消耗、環境污染與運輸安全等問題，皆致力於發展智慧型運輸系統。而在智慧型運輸系統的七個子系統中又以自動公路系統為最高科技的一個子系統，也是發展智慧型運輸系統之終極目標。以高速且小車間距前進的自動控制車隊，若遇到路段下游有事故的產生，必定對系統運作產生衝擊。雖然現在的科技還在測試的階段，不過快速的反應事故所帶來的車道阻塞也是先進自動公路系統的關鍵性議題，但目前仍鮮少有自動公路系統發生事故時的相關研究。 本研究是探討在單一自動控制車道之自動公路系統對事故發生時作因應事故之反應，目的在於建立一個自動車輛控制邏輯，使得自動控制車輛能夠安全且順暢的通過事故點，而這些嵌入的交通控制邏輯都是基於基本的安全需求。首先建立事故上游之三個動態區域來規範自動控制車輛在事故上游的車隊拆解、事故引起之跟車及變換車道、以及強制煞車，以車輛相對速率觀點及車間距切入，藉由防止車輛縱向及橫向碰撞來做判斷變換車道之邏輯，並以同樣的觀點建立混合車流跟車之準則。再以程式語言BCB撰寫控制邏輯，做情境敏感度分析，找出車隊規模、車隊初速、鄰近車道車流量、車隊間距對整體車流之影響。

Many countries around the world devote to develop Intelligent Transportation Systems (ITS) to solve congestion problems, which coupled with some issues of incidents, consumption of energy resource, environmental pollution, and transportation safety. Automated Highway System (AHS) is not only the most hi-technical subsystem in the 7 subsystems of ITS, but also the ultimate goal of development of ITS. An automated-control platoon approaching with high speed and small vehicular spacing will face to critical impacts when incident occurs on downstream highway. Prompt response to lane-blocking incidents is a critical issue in development of advanced AHS although all the limited existing AHS technologies are on trial. But there are few researches to discuss these issues. This paper focuses on the response to incidents for single-automated-lane highway system to design a control logic which permits automated vehicles (AC) change to adjacent lane. The embedded traffic control logic is based on the safety requirement. First we present three dynamic spatial zones, which are platoon decomposing, incident-induced car-following and lane-changing, and mandatory braking. This paper is focus on embedding control logic with the views of relative velocity and vehicular spacing to make decision of automaic-control vehicles via avoiding longitudinal and lateral collisions. Then, we compose BCB programming language to do sensitivity analyses of many scenarios, and find the relationships between platoon size, platoon speed, variable traffic condition, platoon headway speed and traffic flow.