Otonom Taşıtların Toplu Ulaşım Sistemlerine Entegrasyonu: Potansiyel Trafik ve Çevresel Etkilerin Değerlendirilmesi

Abstract

Otonom taşıtlar, toplu taşımada güvenliği artırma ve hizmet sürekliliğini sağlama potansiyeliyle çığır açıcı bir yenilik olarak son yıllarda öne çıkmaktadır. Kentsel ulaşım yapısını tamamen yeniden şekillendirme potansiyeli, bu araçları araştırmacıların odak noktası haline getirmiştir. Bu çalışma, İstanbul’daki gerçek toplu ulaşım ağları üzerinde, “tedbirli” ve “agresif” olarak tanımlanan iki farklı otonom otobüs sürüş davranışının etkilerini incelemektedir. Trafik verimliliği, güvenliği ve emisyonlar, açık kaynaklı trafik simülasyon platformu SUMO kullanılarak değerlendirilmiştir. İki farklı talep düzeyi (yoğun olmayan ve yoğun saatler), değişen katılım oranları ve iki şerit yönetim stratejisi (ayrılmış şerit ve karma trafik) incelenmiştir. Sonuçlar, tedbirli sürüş davranışının ortalama zaman kaybını artırdığını, agresif sürüş stratejilerinin ise katılım oranı arttıkça bu kaybı azalttığını göstermektedir. Ayrılmış şerit senaryosunda, agresif sürüşün tam uygulaması ortalama zaman kaybını yoğun olmayan saatlerde %400 oranında, yoğun saatlerde ise %240 oranında azaltırken; tedbirli sürüş bunu %360 oranında artırmaktadır. Trafik güvenliği açısından, %100 tedbirli sürüş oranında çakışmalar yoğun olmayan saatlerde %94, yoğun saatlerde %84 oranında azalmaktadır. Agresif sürüşte bu oranlar sırasıyla %63 ve %28’dir. Emisyon analiz sonuçlarına göre, ayrılmış şerit senaryolarında %57’ye varan azalmalar göstermektedir. Otonom otobüslerin en olumlu etkileri ayrılmış şeritlerde gözlemlenmiştir. Buna karşın, karma trafik ortamlarında ve düşük katılım oranlarında etkinlik belirgin biçimde azalmaktadır. Bulgular, trafik verimliliği ile güvenlik arasındaki dengeyi vurgulamakta ve dengeli uygulama stratejilerinin önemine dikkat çekmektedir.

Keywords

• toplu ulaşım
• otonom otobüs
• trafik simülasyonu
• ayrılmış şerit
• karma trafik

Integrating Autonomous Buses into Public Transport Systems: An Assessment of Potential Traffic & Environmental Impacts

Abstract

The concept of autonomous buses (ABs) is emerging as a transformative innovation in public transport, with the potential to enhance safety and ensure service reliability. Their ability to reshape urban transport patterns has become a main focus of research. This study investigates the impact of two AB driving behaviours, defensive and aggressive, on real public transport networks in Istanbul. Traffic efficiency, safety, and emissions were evaluated using the open-source traffic simulation platform SUMO. Two demand levels (off-peak and peak hours), varying penetration rates, and two management strategies (dedicated lanes and mixed traffic) were analysed to assess their effects. Results show that AB-defensive behaviour increases average time loss, whereas AB-aggressive strategies reduce it as penetration rises. In dedicated lane scenarios, full deployment of AB-aggressive driving reduces time loss by up to 4.0 times in off-peak and 2.4 times in peak hours compared to the baseline, while AB-defensive driving increases it by up to 3.6 times. Regarding safety, at a 100% AB-defensive rate, conflicts decrease by 94% and 84% in off-peak and peak hours, respectively, whereas AB-aggressive behaviour yields smaller reductions (63% and 28%). CO and HC emissions under dedicated lane scenarios decline by as much as 57%, with aggressive driving providing the greatest benefits. The promising effects of ABs are most evident in dedicated lanes, while in mixed traffic, especially at low penetration rates, their effectiveness declines. Overall, the findings highlight a trade-off between efficiency and safety, emphasizing the need for balanced deployment strategies.

Keywords

• public transport
• autonomous bus
• traffic simulation
• dedicated lane
• mixed traffic

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