Title

LPI Implementation Guidelines in Phoenix, Arizona: A Data Driven Approach

Abstract

As part of work committed towards reducing pedestrian-motor vehicle conflicts and crashes at signalized intersections, researchers within the AZTrans Lab at Northern Arizona University worked with the City of Phoenix, Arizona to develop data driven qualitative public facing guidelines for Leading Pedestrian Interval (LPI) implementation within the City of Phoenix. The first step was to conduct a comprehensive literature review regarding implementation and operation of the LPI, with particular attention paid to operational guidance published by North American jurisdictions regarding implementation guidelines, user feedback, hardware performance, as well as the impact of RTOR and FYA on pedestrian conflicts. Next, a crash analysis using Arizona Department of Transportation crash data (from 2016-2022) was conducted to identify priority locations (locations with high amounts of pedestrian-motor vehicle crashes) for collection of pedestrian – motor vehicle conflicts. Eight crosswalks at four sites were identified, and 10 hours of video was collected at each crosswalk with and without an LPI (160 hours of video total). Then, in an office setting, student researchers watched the video and logged Post-Encroachment Time (PET) for pedestrian – motor vehicle conflicts with an interaction time of 5s or less, pedestrian movement direction during interaction, vehicular movement direction during interaction, conflicting vehicle volume, temporal location of interaction within green interval, physical location of interaction within crosswalk, vehicular and pedestrian compliance with regards to signal indications, and other pertinent data. From this data, PET trends were identified wither respect to conflict location, and used to develop public facing guidelines for LPI implementation. This presentation will profile this work, as well as present lessons learned and ideas for future research.

Presentation

TBD

Speaker Bio

Dr. Edward J. Smaglik, P.E., is a Professor at Northern Arizona University (NAU), Flagstaff, AZ, in the Department of Civil Engineering, Construction Management, and Environmental Engineering. The Director of AZTrans: The Arizona Laboratory for Applied Transportation Research, Dr. Smaglik has over 18 years of academic research and teaching experience, preceded by two years of experience as a post-doctoral research associate and six years as a graduate assistant. Dr. Smaglik has served as the Principal Investigator on transportation related projects over a wide range of topics in this discipline, including improving pedestrian operations and reducing bicycle conflicts at signalized intersections to provide for a more livable environment for all users, mitigating special event congestion through the use of ITS technologies, the development of a sustainable traffic counting device, improving safety on free flow facilities using ITS technologies, investigating the impacts of alternative vehicle detection devices on adaptive traffic control, and the evaluation of emerging transportation technologies. He is past Chair of TRB’s Standing Committee on Traffic Signal Systems (ACP25).

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