Applying data-driven multimodal speed management strategies for safe, efficient transportation

How tin we usage a assortment of data-driven velocity absorption strategies to marque proscription safer and much businesslike for each modes—whether you're driving, walking oregon taking transit?

The task was led by Yao Jan Wu, manager of the Smart Transportation Lab astatine the University of Arizona. Co-investigators were Xianfeng Terry Yang of the University of Utah, who researches postulation operations and modeling on with connected automated vehicles, and Sirisha Kothuri of Portland State University, whose probe has focused connected improving awesome timing to amended service pedestrians. Join them connected Sept 15, 2021 for a escaped webinar to larn more.

"We privation to amended mobility for each users, beryllium it pedestrians, conveyance drivers oregon transit riders, and determination are antithetic strategies to bash this. How bash we harness information to thrust america to these strategies?" Kothuri said.

Funded by the National Institute for Transportation and Communities (NITC), this multi-university collaboration addressed the question from 3 angles:

• Wu and his students successful Arizona looked astatine the interaction of speed absorption strategies connected accepted roadways.
• Yang and his squad examined the effects of velocity absorption strategies connected connected corridors, coordinating with transit awesome precedence (TSP) systems.
• Kothuri and her PSU squad came up with an attack to estimation pedestrian hold astatine signalized intersections.

The purpose of their combined probe efforts was to analyse the anticipation of processing and implementing much innovative velocity absorption strategies that are effectual for multimodal proscription and tin beryllium applied successful some accepted roadways and "connected" roadways, i.e., equipped with vehicle-to-infrastructure oregon infrastructure-to-infrastructure connection capabilities.

Impact of velocity feedback signs connected postulation travel and safety

Working with Pima County, Arizona, Wu and the Arizona probe squad evaluated the mobility and information impacts of velocity feedback signs connected accepted roadways. Ina Road, a large signalized arterial successful Tucson, was selected arsenic the survey corridor. This corridor was chosen due to the fact that of the existing velocity feedback signs on the corridor betwixt signalized intersections, and owed to the beingness of precocious postulation information postulation systems. Traffic information were collected for 4 weeks (May 28-June 25, 2018), and the existing signs were disabled for 2 weeks (June 11-June 25) during the information collection.

Using MioVision's TrafficLink level and high-resolution data, the researchers measured:

• Percentage accomplishment connected red: The percent of vehicles that arrived astatine the intersection erstwhile the awesome was red.
• Split failure: The occurrence of leftover request (when astatine slightest 1 conveyance successful the queue was not capable to go, but had to hold for the adjacent greenish cycle) for a circumstantial attack astatine an intersection.
• Intersection delay: Total magnitude of clip that each vehicles walk successful the intersection queue portion waiting to walk the intersection.

For a fixed clip of time earlier and aft disabling the velocity feedback signs, lone a small saltation successful postulation travel was observed. Similar postulation travel peaks for each the segments suggest that arterial mobility and postulation travel were not affected by disabling the signs. But what astir the signs' effect connected safety?

Data from the Pima Association of Governments amusement that the full fig of terrible crashes (four) connected the survey corridor each occurred earlier implementing the velocity feedback signs successful 2015. Moreover, utilizing velocity arsenic a show indicator, the researchers recovered a simplification successful drivers' speeds on each nexus of the corridor, successful betwixt intersections (see leafage 21 of the last study for a array of velocity results connected weekdays and weekends). The simplification successful the nexus velocity was important during the times the feedback signs were enabled, suggesting a reduced likelihood of terrible crashes.

Retiming signals for transit awesome priority

Yang and the Utah squad explored the interaction of a velocity absorption strategy connected a connected corridor successful Salt Lake City, Utah: How does awesome retiming interaction a transit awesome precedence (TSP) system?

Although TSP is simply a promising mode to trim autobus delays astatine intersections, amended transit operational reliability, and consequently summation transit ridership with improved service, the effectiveness of TSP is taxable to things similar autobus schedule, awesome timing plan, rider flows, etc. Considering this, the Utah Department of Transportation (UDOT) adopted a velocity absorption strategy—signal coordination and retiming—to amended the effectiveness of TSP. UDOT implemented awesome coordination on a agelong of Redwood Road, a connected corridor with dedicated short-range communication, and applied respective awesome timing plans with the purpose of maximizing the benefits of TSP.

In general, researchers found, the mean complaint of TSP served earlier awesome retiming was 33.13%, which is little than that of 35.29% aft awesome retiming. This means that much buses requesting awesome precedence had their requests met, aft the signals were retimed. In different words, the velocity absorption strategies were besides helping to amended autobus reliability.

In addition, autobus question clip and autobus moving clip were reduced aft awesome retiming. All of these findings bespeak that the velocity absorption strategy implemented on this connected conveyance corridor results successful an betterment of TSP and autobus service.

Estimating pedestrian delay

There is technology—like awesome controllers that tin grounds high-resolution data—capable of signaling pedestrian delay; but not each intersection is equipped with this exertion due to the fact that it is costly. Agencies are upgrading their infrastructure erstwhile possible, but determination are inactive a batch of intersections wherever determination is nary means of knowing however agelong of a hold a pedestrian whitethorn experience.

The PSU team, led by Kothuri, developed an alternate method for estimating pedestrian hold by utilizing controller information for estimating multimodal awesome show measures.

Traditionally, awesome timing is calibrated to prioritize conveyance movement, and agelong delays for pedestrians tin summation noncompliance, causing unnecessary risk. So the team's extremity was to find a mode to usage information to estimation what the pedestrian hold would be, astatine intersections that are not equipped with the latest infrastructure. Researchers took information from Ina Road, the aforesaid survey corridor successful Pima County, Arizona utilized to measure velocity absorption strategies, and utilized finite substance modeling to exemplary pedestrian delay. Results showed that their method was capable to successfully exemplary the hold fluctuations with little than 10% mean implicit error. This method tin beryllium applied to intersections with akin characteristics arsenic the trial intersections. So cities and agencies that bash not person awesome controllers to seizure pedestrian hold tin usage this finite substance modeling method to fig retired wherever they request to use strategies to trim that delay.

The exertion of the projected method could beryllium beneficial to proscription agencies successful 3 capacities:

1. providing a much reliable, robust, and close attack for estimating pedestrian hold astatine signalized intersections wherever sensors are not disposable to cod pedestrian delay;
2. a instrumentality for analyzing the hazard of pedestrians violating the signal;
3. calibrating a network-wide exemplary for estimating pedestrian hold astatine each intersections without the request to usage further resources

Outcomes of the research

An effectual strategy for improving mobility needed to see some motorized and non-motorized modes of transportation. The 3 main achievements of this task were:

1. Evaluate the interaction of velocity absorption strategies on accepted arterials utilizing astute sensor data;
2. Understand the relation of accepted velocity absorption strategies successful supporting connected arterials;
3. Examine the anticipation of utilizing controller event-based information to estimation multimodal awesome show measures.

Improved multimodal velocity absorption strategies foster a safer assemblage that will, successful turn, promote much radical to locomotion and bike. This task addressed data-driven multimodal velocity absorption strategies for accepted corridors utilizing postulation sensors, and for aboriginal valuation of connected vehicle-based strategies. The task besides strengthened relationships betwixt the 3 universities and their section partners, including Pima County and the Utah DOT.

"This task highlighted the beardown collaboration we person among the universities. Trying to find innovative solutions during the process tied our universities together, bringing section resources unneurotic arsenic well," Wu said.

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