Rectangular Rapid Flashing Beacons Research Articles

Modeling Pedestrian Near-Crash Events at a Rectangular Rapid Flashing Beacon-Controlled Intersection Using Video Analytics and Long Short-Term Memory Neural Network

Pedestrian safety is a long-standing issue in urban areas, where pedestrian near-crash events are more frequent than in suburban or rural areas. To address the pedestrian safety problem, a proactive approach was explored to assess and predict the severity of these events, which are valuable indicators of potential crashes. Object detection and tracking techniques were used to establish the temporal relationship of pedestrian near-crash events involving vehicles at an intersection controlled with rectangular rapid flashing beacons. A long short-term memory (LSTM) neural network model is proposed to warn a driver 2 s before the vehicle reaches the conflict zone. However, this scenario can be considered optimistic, as the 2 s interval represents an ideal driver’s reaction time, which is more likely to happen in a connected and automated vehicle environment where vehicles receive real-time information about their surroundings and perform some basic tasks such as braking without waiting for the driver reaction. The results demonstrate the effectiveness of the proposed LSTM neural network model, with an area under the curve value of 78.5% on the training data and an overall recall of 71.1% on the test data. The practical significance of this model is its potential to provide timely information about near-crash events, thereby enhancing pedestrian safety at critical points such as intersections.

Evaluating current and future pedestrian mid-block crossing safety treatments using virtual reality simulation

Virtual reality (VR) simulation offers a proactive, cost effective, immersive, and low risk platform for studying pedestrian safety. Within immersive virtual environments (IVEs), existing and alternative design conditions and intelligent transportation systems (ITS) technologies can be directly compared, prior to real-world implementation, to assess the impacts alternatives may have on pedestrian safety, perception, and behavior. Environmental factors can be controlled within IVEs so that test trials are replicable and directly comparable. Coupled with stated preference feedback, participants’ observed preferences and behavior provide a comprehensive understanding of the impacts of proposed design alternatives. This research presents a case study of pedestrian behavior with three different mid-block crossing safety treatments modeled within a one-to-one scale IVE replication of a real-world location in Charlottesville, Virginia. The three safety treatments consider both passive and active collision avoidance designs and technologies, including (1) the existing painted crosswalk, (2) the addition of rectangular rapid flashing beacons (RRFBs), and (3) a pedestrian to everything (P2X) ITS phone application. Additionally, this paper demonstrates a VR simulation experimental design and framework for testing pedestrian safety treatments within naturalistic and replicable IVEs to assess both stated and observed preferences and behaviors of pedestrians. Repeated measures ANOVA indicated changes in both accepted gap size (p = 0.001) and crossing speed (p < 0.001) with alternative safety treatments. Generalized mixed models showed that pedestrians waited for statistically larger gap sizes (p = 0.02) without the assistance of alternative safety technologies (RRFBs and P2X application) and pedestrians crossed the street significantly faster (p = 0.001) without the alternative safety technologies, leading to unsafe dashing behavior. Through post-experiment surveys, it was found that participants perceived the As Built environment to be the least safe of the three treatments and that their sense of risk within the IVE was realistic. Considering both the observed crossing behavior and stated feedback, pedestrians exhibited intentionally unsafe darting behavior without assistive safety technology. This study demonstrates how VR simulation may be leveraged to study both stated preferences and observed behavior for understanding the safety implications of alternative roadway designs, providing a proactive approach for assessing and designing for pedestrian safety.

Real-world crash configurations and traffic violations among newly licensed young drivers with different route familiarity levels

Objective Young drivers aged 24 and below are at heightened risks of being influenced by their route familiarity levels. This study aims to compare prevalences of crash culpability, crash configurations and risky driver behaviors among newly licensed young drivers when they are driving on roads with different route familiarity levels. Methods Based on the road traffic crash and violation data in Yunnan Province of China from January 2017 through December 2019, we classified drivers’ different route familiarity levels by utilizing spatial distance away from residence-based method, including driving on high route familiarity (HRF) and low route familiarity (LRF) roads. Prevalence ratios were estimated using generalized estimating equation log-binomial regression models. Results We identified 12016 newly licensed young drivers driving on HRF roads and 2189 drivers on LRF roads. Within 48 months of licensure, young drivers on LRF roads were more likely to be at fault for their motor vehicle crashes than those on HRF roads. Young drivers on LRF roads were more likely to be with failure to obey traffic control device, with failure to yield right of way, wrong way driving, backing unsafely and improper parking compared with those on HRF roads. Drivers on LRF roads were less likely to be inattentive and driving with unsafe speed and following too closely compared with those on HRF roads. Conclusions Several basic aspects of targeted countermeasures can be put forward. Visual impacts such as rectangular rapid-flashing beacon (RRFB) can be used in order to prevent wrong way driving on the tourist roadways. Arranging safety talks and programs in colleges and universities and technical interventions like Advanced Driver Assistance Systems (ADAS) can be used to reduce young drivers’ driving distraction and overconfidence. It is recommended that the driving schools can use these research findings to include in licensure program to make young drivers more aware of the various factors that expose them to crash risks so that more defensive driving may be needed under different situations, and this can also help build the graduated driving licensure (GDL) programme in China.

Safety Effectiveness of Rectangular Rapid Flashing Beacons Pedestrian Enhancement

A rectangular rapid flashing beacon (RRFB) is a pedestrian crosswalk countermeasure system that cautions drivers by providing them with real-time warning about the presence of pedestrians in an upcoming crosswalk. This paper investigated the safety effectiveness of existing RRFBs installed in the state of Florida between 2013 and 2018. Additionally, traffic volume, roadway characteristics, and land-use mix were included as explanatory variables. The study evaluated 154 treated sites with RRFB installations and 158 control sites with similar characteristics. Safety performance functions (SPF) were developed, and crash modification factors (CMF) were calculated using the empirical Bayes (EB) methodology for various crash types. A CMF of 0.31 for total pedestrian crashes was estimated, showing that RRFBs have the potential to reduce 69% of total pedestrian-involved crashes. CMF for total vehicular crashes and rear-end crashes were also investigated to ascertain whether RRFBs have adverse effects on rear-end crashes. CMF for total vehicular crashes was found to be 1.14, showing that RRFBs do not have positive effect in reducing total vehicular crashes. Similarly, it was observed that CMF for the rear-end crashes was 1.11, indicating RRFBs might have adverse effect on rear-end crashes because vehicles needs to slow down or stop due to the presence of pedestrians. CMFunctions for significant variables for pedestrian, rear-end, and total crash models were also estimated in this study. An economic analysis indicated that the implementation of RRFBs will yield a benefit to cost ratio (calculated over 3 years) of approximately 85.5 with a 4% discount rate.

Investigating surrogate safety measures at midblock pedestrian crossings using multivariate models with roadside camera data

This study aims to evaluate and compare Surrogate Safety Measures (SSMs) at five midblock Rectangular Rapid Flashing Beacons (RRFB) and two midblock Pedestrian Hybrid Beacons (PHB) sites in Florida using extensive video data collected over the study period of July to November 2021. Computer vision and data processing resulted in four pedestrian SSMs, namely spatial gap, temporal gap, relative time to collision (RTTC) and Post Encroachment Time (PET). An initial investigation of the SSMs using Mann-Whitney-Wilcoxon tests revealed significant differences in the SSM values across different treatment types and hours of the day. Additionally, univariate regression of spatial gap, and multivariate regression of temporal gap, RTTC and PET revealed significant differences of SSMs across RRFB and PHB sites. The study considered both linear and non-linear (gamma, inverse Gaussian and lognormal) regression models. After considering various traffic and operational parameters, the data were aggregated for each pedestrian-vehicle interaction on each lane to create a total of 395 observations. The SSMs included average spatial gap, temporal gap, RTTC and PET for each interaction of pedestrian and vehicle on each lane. The results indicated that non-linear models performed better than the linear models. Moreover, the presence of the PHB, weekday, signal activation, lane count, pedestrian speed, vehicle speed, land use mix, morning period and pedestrian starting position from the sidewalk have been found to be significant determinants of the SSMs. Results also suggest temporal SSMs increase at the PHB sites compared to the RRFB sites, indicating an improvement of traffic safety at PHB sites. However, the spatial gap decreased for PHB sites compared to the RRFB sites, which suggests that pedestrians tend to start to cross the RRFB sites when they perceive vehicles to be further away than at the PHB sites.

Lighting Strategies to Increase Nighttime Pedestrian Visibility at Midblock Crosswalks

In the last decade, pedestrian fatalities at night, especially at midblock locations, have been increasing at an alarming rate. Lighting is an effective countermeasure in reducing nighttime crashes. However, few studies have evaluated the effects of crosswalk lighting on pedestrian visibility at midblock locations. There is an existing need to develop lighting designs that increase pedestrian visibility. Further, the safety effects of lighting have never been directly compared to other pedestrian-crossing treatments (such as flashing signs, rectangular rapid flashing beacons (RRFBs), etc.). Thus, in order to make effective recommendations for increasing nighttime pedestrian visibility, it is important to compare the visibility benefits of crosswalk lighting designs with and without pedestrian-crossing treatments. This study evaluated the visual performance of five midblock crosswalk lighting designs along with two pedestrian safety countermeasures at three light levels on a realistic midblock crosswalk. Visual performance was measured by calculating the distance at which the participants could detect a child-sized mannequin under the evaluated conditions. The results showed that midblock crosswalks should be illuminated to an average vertical illuminance of 10 lux to ensure optimal pedestrian visibility. Lighting designs that render the pedestrian in positive contrast (area in front of the crosswalk is illuminated) are recommended to increase pedestrian visibility. It is also recommended that pedestrian-crossing treatments, such as RRFBs and flashing signs, should be used with lighting to increase nighttime visibility.

Factors affecting injury severity at pedestrian crossing locations with Rectangular RAPID Flashing Beacons (RRFB) using XGBoost and random parameters discrete outcome models

This paper evaluates the effectiveness of Rectangular Rapid Flashing Beacons (RRFB) on crash severity. The study used and compared XGBoost and Random Parameters Discrete Outcome Models (RPDOM) respectively. The dataset comprises of 312 pedestrian crossing locations, among which 154 treatment locations were provided with the Rectangular Rapid Flashing Beacons (RRFB) and 158 control locations without RRFB. These control locations have similar roadway, traffic, and land use characteristics of that of the treatment locations but are not treated with RRFB or other pedestrian crossing countermeasures. This study shows the impact of RRFB and other factors on severity of nighttime, pedestrian, total and rear-end crashes. Crash severity data was compiled from driver, vehicle, and event level data of each crash. Due to availability of larger number of observations for total (35,553), rear-end (15,675) and nighttime crashes (8,144) XGBoost was used, and due to less observations for pedestrian crashes (369), it was modeled using RPDOM. The results showed positive impact of RRFB for the reduction of nighttime crashes. It was noted that RRFB reduces the K and A nighttime crashes according to the SHAP values from the XGBoost model but does not have the desired significance for rear end and overall total crashes in the study area. From the RPDOM, it was seen that RRFB showed statistically significant reduction in injury severity of pedestrian crashes and nighttime crashes. To compare the two models, nighttime crashes were modeled using both the techniques, the prediction accuracy of XGBoost Model was 97% which was much greater than that of the RPDOM at 73.8% prediction accuracy. Thus, both XGBoost and the RPDOM model for showed positive impact of installing RRFB in reducing the severity of nighttime crashes.

The role of crosswalk-related features on drivers' spatial yielding compliance at signalized midblock crosswalks

The drivers' yielding distance to pedestrians at midblock crosswalks affects pedestrians' perceived safety. This distance can be influenced by either crosswalk-related or non-crosswalk. In most cases, crosswalk-related features are readily available or easy to collect compared to non-crosswalk features. However, the extent to which crosswalk-related features affect the spatial yielding compliance is not clear. This study evaluated the role of combined crosswalk-related features on drivers' spatial yielding compliance at signalized midblock crosswalks. The study used observational survey data collected from fifteen flash-based signalized midblock crosswalks located in Las Vegas, Nevada. Three logistic regression models, with crosswalk-related features only, non-crosswalk features only, and combined features, were developed and compared. It was revealed that the performance difference between the model with crosswalk-related features only and combined features was insignificant. This study found that the presence of state's law signs, “PED XING” signs, and placement of rectangular rapid flashing beacons (RRFBs) on the advanced pedestrians crossing signs (APCSs), are significant factors for high spatial yielding compliance. On the contrary, the yield line's presence at a distance greater than 40 ft from the crosswalk, presence of one stage crossing, and high Annual Average Daily Traffic (AADT) negatively affects the spatial yielding compliance. Moreover, the findings suggest that researchers should be careful about excluding the non-crosswalk features from the analysis. To improve spatial yielding compliance, several recommendations that the city planners and engineers can adopt are provided. • This study evaluated drivers' yielding compliance at the midblock crosswalk. • The influences of various features on spatial yielding compliance were evaluated. • The state's law and “PED XING” signs increases spatial yielding compliance. • A longer distance from yield lines to marked strips decreases spatial yielding compliance.

Estimating effectiveness of speed reduction measures for pedestrian crossing treatments using an empirically supported speed choice modeling framework

Pedestrian crossing treatments, such as Pedestrian Hybrid Beacons (PHBs) and Rectangular Rapid-Flashing Beacons (RRFBs), are traffic control devices implemented to help pedestrians safely cross busy or higher-speed roadways at midblock crossings and uncontrolled intersections. This study aims to assess the effectiveness of the PHB and RRFB by analyzing drivers’ speeding behavior under different roadway types with real-life traffic conditions. In order to understand the effect of pedestrian crossing treatments (i.e., PHB and RRFB) have on drivers’ speeding behavior, this paper analyzes four zones (i.e., one upstream zone and three consecutive downstream zones). For the four analysis zones, different indexes were computed which corresponds to the differences in drivers’ speed when encountered with the pedestrian crossing treatments. A grouped random effect hurdle beta regression model is estimated for the indexes, with a fixed effect hurdle beta model used for comparison and validating the importance of considering the grouped random heterogeneity across participants. The proposed analysis framework was validated by the means of an empirical driving simulator study, based on two urban roads in the Central Florida region, North Alafaya Trail (SR-434) and South Orange Blossom Trail (US-441). The results revealed that the proposed modeling framework reflects drivers’ difference in speed for the different pedestrian crossing treatments. The results suggest that with proper understanding of the PHB, the PHB can reduce drivers speed even beyond the location of the PHB. Meanwhile, the RRFB does have some effect in speed reduction beyond the location of the RRFB, however many drivers failed to acknowledge the RRFB. It is suggested that when drivers’ have proper education on the use of the PHB to reduce speed safely and for the installation of RRFB be on roads with two or less lanes and a speed limit less than 40 mph. While the main purpose of the pedestrian crossing treatments is to help pedestrians cross safely, speed reduction can be considered a byproduct as revealed in this study.

Effectiveness of modified pedestrian crossing signs in an urban area

The District of Columbia currently uses the standard pedestrian warning signs and diagonal arrow plaques at a substantial number of uncontrolled crosswalks within the City. However, the widespread use of these measures appears to be ineffective in curbing the incidence of pedestrian involved crashes or pedestrian-vehicle conflicts. To compensate for the perceived lack of effectiveness of the standard pedestrian warning sign the District Department of Transportation developed a new side-of-street crossing sign to improve driver compliance based on pedestrian right-of-way laws. This study was aimed at determining the effectiveness (defined as the proportion of drivers approaching a crosswalk who stop or yield the right of way to a pedestrian in the crosswalk) of the experimental side-of-street pedestrian crossing sign compared to the standard sign, with and without rectangular rapid flashing beacons. Effectiveness of the side-of-street pedestrian sign and standard sign were observed at a total of 32 locations in the District over a one-year period using the “control” and “experimental” comparison approach. Video data for each location was obtained from March 2018 through February 2019 during typical weekdays for the morning and afternoon peak periods. The results of the study showed that the experimental signs with RRFBs provided higher driver compliance rates (yielding to pedestrians) compared to the standard signs for both the morning and afternoon peak periods. However, the differences in compliance rates for the experimental and standard signs were not statistically significant at a 95% confidence interval. Further evaluation of the signs is recommended using the “before” and “after” approach in addition to an assessment of crash statistics at the selected locations.

Driving behavior at midblock crosswalks with Rectangular Rapid Flashing Beacons: Hidden Markov model approach using naturalistic data

Pedestrian fatalities have increased in the U.S. with the largest increase being observed on urban arterials and away from intersections. Rectangular Rapid Flashing Beacon (RRFB) has been widely implemented as a safety countermeasure to improve driver awareness and visibility of pedestrians, especially for midblock crosswalks. Studies show that drivers are more likely to yield to pedestrians at crosswalks with an RRFB. These studies are often based on a binary outcome of whether or not drivers yield to pedestrians. Nevertheless, it is also important to consider the drivers’ deceleration behavior as a dynamic process at these crosswalks and the impact of pedestrians being present or not. Understanding this dynamic behavior and the related circumstances can provide information on the design of alerting systems that help drivers make more appropriate decisions at these crosswalks to avoid a vehicle–pedestrian crash. This study examined this research topic using Hidden Markov Models (HMMs) and data from a naturalistic study. More specifically, four HMMs were applied to the naturalistic brake and jerk data from the Safety Pilot Model Deployment (SPMD) program given drivers’ intention to slow down, the RRFB activation status, and the presence of pedestrians. The time-based data sequence was converted to distance-based through a moving window to enhance result comparison and interpretation. Grid-search was used to select the best moving window parameters and the optimal number of hidden states. This study confirmed the high compliance at an activated RRFB when pedestrians were present. Even without pedestrians, one in five traversals showed drivers slowing down to less than 8.94 m/s (20 mph) within 35 m of the crosswalk. Model results further indicate that drivers started braking as far back as 180 m before the crosswalk and stopped braking from 70 m before the crosswalk at an activated RRFB without pedestrians. When there were pedestrians, drivers would start braking 20 to 30 m later but would brake more firmly and for longer. Finally, drivers were not likely to brake or decelerate when RRFB was off and no pedestrians were present.

Nighttime effectiveness of the pedestrian hybrid beacon, rectangular rapid flashing beacon, and LED-embedded crossing sign

Introduction: A large majority of pedestrian fatal crashes occurred during the nighttime. The focus of this research was to identify if the following pedestrian crossing treatments were more or less effective at night: pedestrian hybrid beacon (PHB), rectangular rapid flashing beacon (RRFB), or LED-embedded crossing warning sign (LED-Em). Method: For each treatment, two statistical evaluations were used on the staged pedestrian data: ANCOVA models that considered per site mean yield rates and logistic regression that considered the individual driver response to the crossing pedestrian. Results: For the PHB, essentially no difference was found between the very high daytime and nighttime driver yielding values. The research found RRFBs to be more effective at night, and the LED-Em to be more effective during the day. Using the results from the logistic regression evaluation, higher driver yielding was observed at LED-Em sites in the lower speed limit group (30 or 35 mph (48.3 or 56.3 kph), with 2 lanes (rather than 4 lanes), with narrow lanes of 10.5 or 11 ft (3.2 or 3.4 m) widths (rather than 11.5 or 12 ft (3.5 or 3.7 m) widths), and lower hourly volumes. The results from the ANCOVA model for LED-Ems also showed a statistically significant difference for yield lines (higher yielding when present). Conclusions: This analysis represents the only known study to date on the effectiveness of pedestrian crossing treatments at night. Practical Applications: This study provides additional support for the PHB as a treatment because the PHB was found to be highly effective during the nighttime as well as the daytime. The value of using advance yield lines was also demonstrated. The findings offer a caution regarding the use of the LED-Em treatment on higher speed, higher volume, or wider roads.

Driver Yielding and Pedestrian Performance at Midblock Crossings on Three-Lane Roadways with Rectangular Rapid Flashing Beacons

Rectangular rapid flashing beacons (RRFBs) have proven to be a useful tool for improving driver yielding and pedestrians’ safety at midblock crossings. This study analyzed driver yielding at 23 RRFB-enhanced midblock crossings on three-lane roadways with and without median refuge islands in Oregon. The locations were chosen to represent a range of posted speed limits and average daily traffic that aligns with existing guidance for median and beacon installations. Sites were classified either as (a) no median refuge, RRFBs placed outside the roadway, (b) median refuge, RRFBs placed outside the roadway, (c) median refuge, RRFBs placed on the island and outside the roadway. Yielding was determined following protocols established in prior research. Two hundred seventy-six hours of video footage were analyzed, resulting in 3,065 crossing events (1,338 staged; 1,727 naturalistic) undertaken by 3,683 pedestrians. High yielding rates were observed—the average near side yielding rate was 97%, with the lowest site having a rate of 89.9%. Yielding rates were generally higher on the far side. Owing to sample size and consistently high yielding rates, it was not possible to make conclusive observations about the relationship between driver yielding and the presence of median or additional beacons for the volume and speed combinations. The results generally indicated that yielding rates increased with the addition of median beacons. The findings also suggested median refuge islands with a beacon increased yielding. The increase in yielding was statistically significant at sites with average daily traffic of 12,000 to 15,000.

Flashing in-curb LEDs and beacons at unsignalized crosswalks and driver’s visual attention to pedestrians during nighttime

Driver’s visual attention (eye movements) and driving behaviour (kinematic data) were assessed when approaching an experimental crosswalk that included flashing white in-curb LED strips, flashing orange beacons, backlit ‘Yield here to pedestrians’ vertical signs, and enhanced lighting when a staged pedestrian attempted to cross. An experimental condition in which all devices were active was compared with a control condition in which only enhanced lighting and backlit vertical signs were active. The results showed a significant increase of motorists’ yielding compliance, distance of first fixation to the pedestrian area, standard deviation for horizontal eye movements in the experimental condition. The introduction of flashing in-curb LED strips and flashing orange beacons proved to be very effective in increasing the night-time safety of the pedestrian crossing. Practitioner summary: The study investigated the effects of flashing in-curb LED strips and beacons on driver’s visual attention (eye movements) and speed when approaching a crosswalk during night-time. The results showed that the combination of these flashing devices significantly increased yielding compliance and the distance of pedestrian detection. Abbreviations: ANOVA: analysis of variance; EU: European Union; HAWK: high intensity activated crosswalk system; LED: light-emitting diode; PHB: pedestrian hybrid beacons; ROI: region of interest; RRFB: rectangular rapid flashing beacons; UK: United Kingdom; US: United States

Comparison of LED-Embedded Pedestrian Crossing Signs with Rectangular Rapid Flashing Beacons and Pedestrian Hybrid Beacons

To date, the effectiveness of light emitting diode (LED)-embedded pedestrian crossing signs is not understood, despite such signs being installed and used at pedestrian crossings. A recent study by Texas Department of Transportation focused on examining driver yield rates, a surrogate safety measure, for signs installed across the state. A total of 13 sites were sampled and field observations and video footage were recorded at each site for a total of 681 staged crossings. The driver yield rate ranged from 5% to 88%, with an average of 40%, indicating that other factors affect the effectiveness of the signs. Statistical modeling results supported this finding with the main contributors to driver yield rates being vehicle volume, measured at 1 min before the staged pedestrian crossing (converted to an hourly volume for the model), operational speed (85th percentile), deviation from 12-ft lane width, and presence of sidewalk. High hourly volume, speeds 45 mph and greater, lack of sidewalks, and 12-ft lanes (no deviation from baseline 12-ft lane width) were found to affect yield probability adversely. Based on the findings from this study, LED-embedded signs would be a suitable candidate treatment at sites with sidewalks, lower operating speeds and traffic volumes, and narrow lanes. Lastly, a comparison between driver yield rates for rectangular rapid flashing beacons, pedestrian hybrid beacons, and LED-embedded signs for various posted speed limits demonstrated that, of the three treatments, LED-embedded signs have the lowest driver yield rates, especially for higher posted speed limits.

Measuring Compliance of Driver Yielding at Enhanced Pedestrian Crossings in Utah

In the 2000s, the Utah Department of Transportation (UDOT) began implementing technological enhancements to reduce the fatality rate of pedestrians involved in crashes. Although these enhancements appeared to be successful at improving safety, there was a need to evaluate their effectiveness. This research evaluates the safety impacts of several pedestrian crossing enhancements using Utah-specific compliance rates of drivers as a surrogate safety measure. This study analyzes enhanced pedestrian crossings to determine the factors that affect the compliance of driver yielding in Utah and provides a statistical analysis to prove the significance of each factor on compliance. The results show that the “High-intensity Activated crossWalK” (HAWK) is more effective at reducing the probability of a non-compliant event compared with an overhead flashing beacon (OFB), and that an OFB is more effective at reducing the probability of a non-compliant event compared with a rectangular rapid flashing beacon (RRFB) or an overhead rectangular rapid flashing beacon (ORRFB). The results show that adding a pedestrian enhancement to a marked crosswalk at a location with five lanes and speed limit between 35 mph and 45 mph can increase compliance rate by 97% for the HAWK, 77% for the OFB, and 57% for the RRFB and ORRFB.

Evaluating the influential factors for pushbutton utilization at signalized midblock crosswalks

This study applied Logistic Regression (LR) on observational survey data to evaluate the factors associated with pedestrians’ utilization of pushbuttons at signalized midblock crosswalks. The study data was collected from twenty signalized midblock crosswalks located in Las Vegas, Nevada. These crosswalks are equipped with either Rectangular Rapid Flashing Beacons (RRFBs), Circular Rapid Flashing Beacons (CRFBs), Circular Flashing Beacons (CFBs), Traffic Control Signals (TCSs), or Pedestrians Hybrid Beacons (PHBs). The regression results revealed the association between pushbutton utilization and various human, infrastructure, and traffic related factors. Among the human factors, the arrival sequence to the crosswalks was found to have the highest impact on warning light activation tendency, as first arriving pedestrians were eight times more likely to press the pushbutton. Moreover, males, the elderly, children, and teens are also less likely to press pushbuttons. Furthermore, pedestrians involved in secondary activities such as carrying/holding things in their hands, have relatively low odds ratio of pressing the pushbutton, while phone use was a statistically insignificant factor. Of the infrastructure factors, in comparison to TCSs and PHBs, all flash-based signal types (CRFBs, CFBs. and RRFBs) are associated with increased pushbutton pressing. The crosswalks located in residential locations are also associated with higher odds of pressing the pushbutton, as compared to the ones located in mixed land. A greater number of lanes and higher oncoming vehicle speeds are associated with higher odds of pressing a pushbutton. These findings can be crucial to city engineers and planners in improving pedestrian safety at midblock crosswalks.

Modeling Transitional States of Drivers Yielding Right-Of-Way to Pedestrians at Signalized Midblock Crosswalks using a Hazard-Based Multistate Model

This study presents an analysis of transitional states of drivers yielding right-of-way to pedestrians at signalized midblock crosswalks. The study utilizes data from twenty signalized midblock crosswalks located in Las Vegas, Nevada, equipped with traffic control signals (TCSs), pedestrians hybrid beacons (PHBs), circular flashing beacons (CFBs), circular rapid flashing beacons (CRFBs), and rectangular rapid flashing beacons (RRFBs). It applies both descriptive analysis and multistate models to explore the variations in transition durations and factors associated with the states’ transition of drivers yielding right-of-way, namely non-yield, multiple-threats, and full yield. The study found that RRFBs are the signal types that have a high frequency of multiple-threats state. The duration to reach full yield varies between 0 s and 318 s; the duration of non-yield to multiple-threats varies between 1 s and 105 s; whereas multiple-threats to full yield duration varies between 1 s and 38 s. The multistate model results show that only the signal type factor has a clear pattern. For this factor, the RRFBs showed low hazard ratios for all three transitions, when compared with CFBs and CRFBs. In various ways, the states’ transition durations were also associated with the number of cross stages, number of lanes, vehicle density, incoming vehicle speeds, annual average daily traffic, and number of pedestrians crossing, as well as their crossing positions. The developed model can be used by engineers and planners to evaluate factors affecting the effectiveness of the crosswalk treatments.

An Automatic Trigged Rectangular Rapid Flashing Beacons (RRFB) System Using the Roadside LiDAR Sensor

The existing rectangular rapid flashing beacons (RRFB) could not be automatically trigged with acceptable accuracy. This paper introduces a strategy to develop an automatic trigged RRFB system using the roadside Light Detection and Ranging (LiDAR). The trajectories of the road users can be extracted in real-time with the proposed LiDAR data processing algorithms. The pedestrian/bicycle crossing intention was predicted with Naive Bayes (NB) classifier. Different detection zones were provided to detect the pedestrian/bicycle crossing movements in real-time. The updated RRFB system was implemented at one intersection in Henderson, Nevada, United States. The results of the field test showed that the overall false rate of the updated RRFB system is very low (0.68%). The performance of the proposed method is superior compared to the state-of-the-art method. The updated RRFB system can greatly improve pedestrian safety at unsignalized intersections.

Factors associated with compliance rate at pedestrian crosswalks with Rectangular Rapid Flashing Beacon

In the recent decade, Rectangular Rapid Flashing Beacon (RRFB) has been introduced and widely installed across North America to improve pedestrians’ safety at crosswalks. While the treatment has been reported to be effective in improving safety, relatively few studies have been conducted to explore the factors associated with its effectiveness. This study investigates the effect of road characteristics, environmental factors, and device specification on vehicles’ yielding compliance, used as a surrogate measure of safety. Nineteen crosswalks within the City of Calgary were chosen for field study. An ordinary least squares regression model is applied to identify the factors that affect the compliance rate. It is found that type of road, daily traffic volume, posted speed limit, median, and rainy weather have significant impacts on the compliance rate. Besides, the result suggests using smaller size beacons and installing them above the pedestrian sign to improve safety to its fullest at RRFB-enhanced crosswalks.