Truck platooning enabled by connected automated vehicle (CAV) technology has been demonstrated to effectively reduce fuel consumption for trucks in a platoon. However, given the limited number of trucks in the traffic stream, it remains questionable how great an energy saving it may yield for a practical freight system if we only rely on ad-hoc platooning. Assuming the presence of a central platooning coordinator, this paper is offered to substantiate truck platooning benefits in fuel economy produced by exploiting platooning opportunities arising from the United States’ domestic truck demands on its highway freight network. An integer programming model is utilized to schedule trucks’ itineraries to facilitate the formation of platoons at platoonable locations to maximize energy savings. A simplification of the real freight network and an approximation algorithm are used to solve the model efficiently. By analyzing the numerical results obtained, this study quantifies the importance of scheduled platooning in improving trucks’ fuel economy. Furthermore, the allowable platoon size, schedule flexibility, and fuel efficiency all play a crucial role in energy savings. Specifically, by assuming that following vehicles in a platoon obtain a 10% energy reduction, an average energy reduction of 8.48% per truck can be achieved for the overall network if the maximum platoon size is seven, and the schedule flexibility is 30 min. The cost–benefit analysis provided at the end suggests that the energy-saving benefits can offset the investment cost in truck platooning technology.
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Improving Truck Merging at Ramps in a Mixed Traffic Environment: A Multi-human-in-the-loop (MHuiL) Approach
Freeway ramp merging is a challenging task for an individual vehicle (in particular a truck) and a critical aspect of traffic management that often leads to bottlenecks and accidents. While connected and automated vehicle (CAV) technology has yielded efficient merging strategies, most of them overlook the differentiation of vehicle types and assume uniform CAV presence. To address this gap, our study focuses on enhancing the merging efficiency of heavy-duty trucks in mixed traffic environments. We introduce a novel multi-human-in-the-loop (MHuiL) simulation framework, integrating the SUMO traffic simulator with two game engine-based driving simulators, enabling the investigation of interactions between human drivers in diverse traffic scenarios. Through a comprehensive case study analyzing eight scenarios, we assess the performance of a connectivity-based cooperative ramp merging system for heavy-duty trucks, considering safety, comfort, and fuel consumption. Our results demonstrate that guided trucks exhibit advantageous characteristics, including an enhanced safety margin with larger gaps by 23.2%, a decreased speed deviation by 30.4% facilitating smoother speed patterns, and a reduction in fuel consumption by 3.4%, when compared with non-guided trucks. This research offers valuable insights for the development of innovative approaches to improve truck merging efficiency, enhancing overall traffic flow and safety.
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- Award ID(s):
- 2152258
- PAR ID:
- 10510969
- Publisher / Repository:
- IEEE
- Date Published:
- ISBN:
- 979-8-3503-9946-2
- Page Range / eLocation ID:
- 4297 to 4302
- Format(s):
- Medium: X
- Location:
- Bilbao, Spain
- Sponsoring Org:
- National Science Foundation
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