Connected and automated vehicles can improve future transportation systems. Using advanced technologies, including sensing technology, CAVs can enhance vehicle efficiency, reduce accidents, and positively improve greenhouse gas emissions. CAVs also have the potential to overcome traffic congestion and increase roadway capacity. However, the right infrastructure needs to be in place for transportation planners to ensure safe and reliable CAV operations. 

The researchers behind a study published in the Journal of Transportation Engineering, Part A: Systems, “Development of a Knowledge Base for Multiyear Infrastructure Planning for Connected and Automated Vehicles,” performed an extensive literature review to understand the current state of CAV operations, the options currently available, and how to integrate CAVs into transportation agencies’ future infrastructure plans.

Authors Fehintola Sanusi, Juyeong Choi, Yong Hoon Kim, and Ren Moses developed and applied a knowledge base using a case study of Missouri’s and Minnesota’s CAV infrastructure planning for the short, medium, and long term. The case study looked at infrastructure needs based on projected market penetration and a long-term vision. Their findings identify some of the short-term requirements (such as traffic signage, lane markings, and pavement surface conditions), as well as the long-term aspects to consider including the pace of adoption and the differences in sensor technology. The researchers suggest that planning agencies and stakeholders collaborate with automakers to understand the emerging CAV technologies and develop infrastructure plans to ease CAV rollout. Their paper is available in the ASCE Library at https://doi.org/10.1061/JTEPBS.0000656. The abstract is below. 

Abstract

Connected and automated vehicles (CAVs) require proper infrastructure for safer and more reliable operations. Many state and local planning agencies have developed multiyear capital programs to provide such infrastructure in a timely manner within their limited budgets. Meanwhile, the traffic environment will evolve over time as CAV technologies become available (i.e., toward the mixed environment of CAVs and human-driven vehicles), which requires infrastructure plans specific to different planning terms (i.e., short-, medium-, and long-term) to accommodate changing infrastructure needs. To develop an effective multiyear infrastructure plan, planning agencies need to understand changing infrastructure needs with time, identify alternative infrastructure options for different planning terms, and select the most appropriate ones based on their long-term vision. This study performed a systematic literature review to develop a knowledge base for multiyear infrastructure planning for CAVs. To be more specific, the literature review aims to develop the following knowledge areas: (1) identification of existing and future infrastructure options for the operation of CAVs, (2) understanding the role of infrastructure to support different functions of CAVs to realize safety, mobility, and environmental benefits, and (3) integration of the aforementioned findings into planning agencies’ multiyear infrastructure plans for CAVs. Based on the review, this study categorizes different CAV infrastructure into existing infrastructure and future infrastructure options while considering five system functions of CAVs (i.e., cooperative merging, platooning, intersection movement, dynamic routing, and cooperation and connected functions) to illustrate the role of these infrastructure options under different traffic scenarios. The implementation of the developed knowledge base is demonstrated through a case study of two selected state agencies’ long-term infrastructure planning for CAVs.

Read the full paper in the ASCE Library: https://doi.org/10.1061/JTEPBS.0000656