Safe Operations at Roadway Junctions - Design Principles from Automated Guideway Transit

Event
Business of Automated Mobility (BAM) Forum
Authors Abstract
Content
This paper describes a system-level view of a fully automated transit system comprising a fleet of automated vehicles (AVs) in driverless operation, each with an SAE level 4 Automated Driving System, along with its related safety infrastructure and other system equipment. This AV system-level control is compared to the automatic train control system used in automated guideway transit technology, particularly that of communications-based train control (CBTC). Drawing from the safety principles, analysis methods, and risk assessments of CBTC systems, comparable functional subsystem definitions are proposed for AV fleets in driverless operation. With the prospect of multiple AV fleets operating within a single automated mobility district, the criticality of protecting roadway junctions requires an approach like that of automated fixed-guideway transit systems, in which a guideway switch zone “interlocking” at each junction location deconflicts railway traffic, affirming safe passage. The analogous AV protection safety subsystem is defined as fail-safe equipment that monitors roadway intersections and junctions, communicates traffic signal status, perceives and communicates alerts and signals to AV connected vehicles concerning potential unsafe conditions, and performs related primary safety functions. Conclusions are drawn that the AV protection roadway intersection functions must be performed by local roadside equipment dedicated to protecting each roadway intersection and junction. Further, it is concluded that the communications technology connecting the infrastructure with the vehicle to perform this vital, fail-safe protection should meet specific functional and performance criteria.
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DOI
https://doi.org/10.4271/2021-01-1004
Pages
10
Citation
Lott, J., Young, S., and Zhu, L., "Safe Operations at Roadway Junctions - Design Principles from Automated Guideway Transit," SAE Int. J. Adv. & Curr. Prac. in Mobility 4(1):260-269, 2022, https://doi.org/10.4271/2021-01-1004.
Additional Details
Publisher
Published
Jun 16, 2021
Product Code
2021-01-1004
Content Type
Journal Article
Language
English