System Integration and Field Tests for Developing In-Vehicle Dilemma Zone Warning System

2003 ◽  
Vol 1826 (1) ◽  
pp. 53-59 ◽  
Author(s):  
Young-Jun Moon ◽  
Jooil Lee ◽  
Yukyung Park
Keyword(s):  
System Integration ◽  
Red Light ◽  
Field Tests ◽  
Warning System ◽  
Field Testing ◽  
Signalized Intersections ◽  
Dilemma Zone ◽  
Stopping Distance ◽  
Real Traffic ◽  
Warning Device

The basis for system integration and field testing was developed for assessing a dilemma zone warning system for signalized intersections. The system consists of hardware (an in-vehicle warning device, roadside antenna, and traffic signal controller) and software to operate and test the integrated component warning and communications systems. Field tests were conducted in real traffic situations to test the system’s warning initiation time from the signal controller, the activation and duration of the visual and audible signals, and the warning delay, on the basis of relationships between distance variables that include the safe stopping distance and the location of roadside antenna. Findings from the field tests at two signalized intersections indicated that the system could be implemented at signalized intersections to eliminate the dilemma zone, relative to approach speeds, and to reduce red-light violations and intersection collisions by means of an in-vehicle warning device.

scholarly journals Using Connected Vehicle Data to Reassess Dilemma Zone Performance of Heavy Vehicles

2020 ◽  
Vol 2674 (5) ◽  
pp. 305-314
Author(s):  
Howell Li ◽  
Tom Platte ◽  
Jijo Mathew ◽  
W. Benjamin Smith ◽  
Enrique Saldivar-Carranza ◽  
...  
Keyword(s):  
Red Light ◽  
Field Tests ◽  
Connected Vehicle ◽  
Heavy Vehicles ◽  
Passenger Cars ◽  
Dilemma Zone ◽  
Passenger Vehicles ◽  
Vehicle Data ◽  
The Us ◽  
Position Data

The rate of fatalities at signalized intersections involving heavy vehicles is nearly five times higher than for passenger vehicles in the US. Previous studies in the US have found that heavy vehicles are twice as likely to violate a red light compared with passenger vehicles. Current technologies leverage setback detection to extend green time for a particular phase and are based upon typical deceleration rates for passenger cars. Furthermore, dilemma zone detectors are not effective when the max out time expires and forces the onset of yellow. This study proposes the use of connected vehicle (CV) technology to trigger force gap out (FGO) before a vehicle is expected to arrive within the dilemma zone limit at max out time. The method leverages position data from basic safety messages (BSMs) to map-match virtual waypoints located up to 1,050 ft in advance of the stop bar. For a 55 mph approach, field tests determined that using a 6 ft waypoint radius at 50 ft spacings would be sufficient to match 95% of BSM data within a 5% lag threshold of 0.59 s. The study estimates that FGOs reduce dilemma zone incursions by 34% for one approach and had no impact for the other. For both approaches, the total dilemma zone incursions decreased from 310 to 225. Although virtual waypoints were used for evaluating FGO, the study concludes by recommending that trajectory-based processing logic be incorporated into controllers for more robust support of dilemma zone and other emerging CV applications.

scholarly journals Using Connected Vehicle Data to Reassess Dilemma Zone Performance of Heavy Vehicles

2020 ◽  
Author(s):  
Howell Li ◽  
Tom Platte ◽  
Jijo K. Mathew ◽  
W. Benjamin Smith ◽  
Enrique Saldivar-Carranza ◽  
...  
Keyword(s):  
Red Light ◽  
Field Tests ◽  
Connected Vehicle ◽  
Heavy Vehicles ◽  
Passenger Cars ◽  
Dilemma Zone ◽  
Passenger Vehicles ◽  
Vehicle Data ◽  
The Us ◽  
Position Data

The rate of fatalities at signalized intersections involving heavy vehicles is nearly five times higher than for passenger vehicles in the US. Previous studies in the US have found that heavy vehicles are twice as likely to violate a red light compared with passenger vehicles. Current technologies leverage setback detection to extend green time for a particular phase and are based upon typical deceleration rates for passenger cars. Furthermore, dilemma zone detectors are not effective when the max out time expires and forces the onset of yellow. This study proposes the use of connected vehicle (CV) technology to trigger force gap out (FGO) before a vehicle is expected to arrive within the dilemma zone limit at max out time. The method leverages position data from basic safety messages (BSMs) to map-match virtual waypoints located up to 1,050 ft in advance of the stop bar. For a 55 mph approach, field tests determined that using a 6 ft waypoint radius at 50 ft spacings would be sufficient to match 95% of BSM data within a 5% lag threshold of 0.59 s. The study estimates that FGOs reduce dilemma zone incursions by 34% for one approach and had no impact for the other. For both approaches, the total dilemma zone incursions decreased from 310 to 225. Although virtual waypoints were used for evaluating FGO, the study concludes by recommending that trajectory-based processing logic be incorporated into controllers for more robust support of dilemma zone and other emerging CV applications.

Performance of Advance Warning for End of Green System for High-Speed Signalized Intersections

2005 ◽  
Vol 1925 (1) ◽  
pp. 176-184 ◽  
Author(s):  
Srinivasa R. Sunkari ◽  
Carroll J. Messer ◽  
Hassan Charara
Keyword(s):  
High Speed ◽  
Red Light ◽  
Signalized Intersections ◽  
Traffic Signal ◽  
Traffic Operations ◽  
Dilemma Zone ◽  
Green Approach ◽  
High Speeds ◽  
Approach Speed ◽  
Green System

A major difficulty with traffic signal operation on high-speed approaches is the dilemma faced by approaching motorists when the downstream signal turns yellow. Should the motorists stop or proceed through the intersection? Crashes that may occur at these intersections result in excessive property damage and personal injury because of the high speeds involved. The Texas Transportation Institute has developed a new system named the Advance Warning for End of Green System (AWEGS) for application at high-speed signalized intersections. Typically, dilemma zone detection strategy is based on a certain approach speed (typically the 85th percentile). AWEGS provides protection for the majority of motorists who are not covered by the dilemma zone treatment. AWEGS provides advance warning to motorists by using signs mounted on the roadside. These signs (Be Prepared To Stop When Flashing) would flash a beacon about 5 to 6 s before the onset of the yellow signal for high-speed approaches. Similar systems have been implemented in Canada and in a few U.S. states that use the trailing-green approach, which results in loss of dilemma zone protection every cycle. AWEGS, however, is almost completely independent of the traffic signal controller, and hence the signal controller would continue to provide the dilemma zone protection for which it was designed. The system was implemented at two sites in Waco and Brenham, Texas. Results of AWEGS implementation illustrated an improvement in traffic operations. AWEGS consistently enhanced the dilemma zone protection at intersections and reduced red light running by about 40%.

scholarly journals Discrimination of Effects between Directional and Nondirectional Information of Auditory Warning on Driving Behavior

2015 ◽  
Vol 2015 ◽  
pp. 1-7 ◽  
Author(s):  
Yuting Zhang ◽  
Xuedong Yan ◽  
Zhuo Yang
Keyword(s):  
Reference Group ◽  
Red Light ◽  
Warning System ◽  
Driving Behavior ◽  
Signalized Intersections ◽  
Directional Information ◽  
Red Light Running ◽  
Collision Warning ◽  
The Relationship ◽  
Auditory Warning

This study examines the impacts of directional and nondirectional auditory warning information in a collision warning system (CWS) on driving behavior. The data on driving behavior is collected through experiment, with scenarios containing unexpected hazard events that include different warning content. As drivers approached the collision event, either a CWS auditory warning was given or no warning was given for a reference group. Discriminant analysis was used to investigate the relationship between directional auditory warning information and driving behavior. In the experiment, the CWS warnings significantly reduced brake reaction time and prompted drivers to press the brake pedal more heavily, demonstrating the effectiveness of CWS warnings in alerting drivers to avoid red-light running (RLR) vehicles when approaching a signalized intersection. Providing a clear warning with directional information about an urgent hazard event could give drivers adequate time to prepare for the potential collision. In terms of deceleration, a directional information warning was shown to greatly help drivers react to critical events at signalized intersections with more moderate braking. From these results, requirements can be derived for the design of effective warning strategies for critical intersections.

Determination and Utilization of Dilemma Zone Length and Location for Safety Assessment of Rural High-Speed Signalized Intersections

2020 ◽  
Vol 2674 (4) ◽  
pp. 272-280
Author(s):  
Min-Wook Kang ◽  
Moynur Rahman ◽  
Joyoung Lee
Keyword(s):  
High Speed ◽  
Red Light ◽  
Signalized Intersections ◽  
Percentage Error ◽  
Traffic Operations ◽  
Safety Level ◽  
Zone Length ◽  
Dilemma Zone ◽  
Intersection Safety ◽  
Traffic Conflicts

The objective of the present study is to see how the dilemma zone length and location are related to intersection safety at rural high-speed signalized intersections. For that, dilemma zones at 30 rural signalized intersection approaches where similar traffic operations and land-use conditions are present were identified, and traffic conflicts associated with the dilemma zones were investigated. Drivers’ stop or go behaviors as well as vehicle dynamics (e.g., vehicle speeds and locations) during the yellow and red clearance intervals were collected and analyzed to determine the dilemma zone length and location of each site. Red-light running violations and vehicles’ abrupt stops were also collected to investigate the relationship between such conflicts and dilemma zone length and location. As a result, two dilemma zone conflict models were developed. The analysis results show that the conflict models are accurate enough to predict the safety level of high-speed signalized intersections using the two dilemma zone variables. Results show that the chance of intersection angle conflicts increases if the dilemma zone is located farther from the intersection stop bar. Results also show that there would be a high chance of rear-end conflicts if the dilemma zone length is longer. The models were validated with additional datasets, and acceptable root means square error and mean absolute percentage error values were obtained as a result.

Evaluating the Benefits of Red-Light Violation Warning System in a Connected Vehicle Simulation Environment

2021 ◽  
pp. 036119812110266
Author(s):  
Mohammed Hadi ◽  
Kamar Amine ◽  
Thodsapon Hunsanon ◽  
Mahmoud Arafat
Keyword(s):  
Rapid Development ◽  
Red Light ◽  
Warning System ◽  
Simulation Models ◽  
Signalized Intersections ◽  
Utilization Rate ◽  
Connected Vehicle ◽  
Microscopic Simulation ◽  
Vehicle Simulation ◽  
Study Results

The rapid development of connected vehicle (CV) and cooperative automated vehicle (CAV) technologies in recent years calls for the assessment of the impacts of these technologies on system performance. Microscopic simulation can play a major role in assessing these impacts, particularly during the early stages of the adoption of the technologies and associated applications. This study develops a method to evaluate the safety benefits of red-light violation warning (RLVW), a CV-based vehicle-to-infrastructure (V2I) application at signalized intersections, utilizing simulation. The study results confirm that it is critical to calibrate the probability to stop on amber in the utilized simulation model to reflect real-world driver behaviors when assessing RLVW impacts. Without calibration, the model is not able to assess the benefits of RLVW in reducing RLR and right-angle conflicts. Based on a surrogate safety assessment, the calibrated simulation models result shows that the CV-based RLVW can enhance the safety at signalized intersections by approximately 50.7% at 100% utilization rate of the application, considering rear-end, and right-angle conflicts.

Driving in the Dust: Challenges and Lessons Learned from Field Testing in Degraded Visual Environments

2020 ◽  
Vol 64 (1) ◽  
pp. 1916-1920
Author(s):  
Kayla L. Riegner ◽  
Kelly S. Steelman
Keyword(s):  
Research Program ◽  
Field Tests ◽  
Field Testing ◽  
Driving Performance ◽  
Lessons Learned ◽  
Current Paper ◽  
Ground Vehicle ◽  
Significant Safety ◽  
Dust Clouds

Degraded visual environments (DVEs) pose significant safety and efficiency problems in military ground vehicle operations. As part of a larger research program, two field tests were conducted to evaluate driving aids while indirect driving in DVEs. The current paper presents the results of one of these field tests, and focuses on the challenges and lessons learned in designing a challenging test course and producing consistent dust clouds for assessing Soldier driving performance and workload in degraded visual environments.

scholarly journals State-of-the-Art-Review of Collapsible Soils

2000 ◽  
Vol 5 ◽  
pp. 115 ◽  
Author(s):  
A. A. AL-Rawas
Keyword(s):  
Field Tests ◽  
Clay Content ◽  
Field Testing ◽  
Dry Density ◽  
Foundation Design ◽  
Treatment Methods ◽  
Collapse Potential ◽  
Collapsible Soils ◽  
Different Types ◽  
Compaction Control

Collapsible soils are encountered in arid and semi-arid regions. Such soils cause potential construction problems due to their collapse upon wetting. The collapse phenomenon is primarily related to the open structure of the soil. Several soil collapse classifications based on parameters such as moisture content, dry density, Atterberg limits and clay content have been proposed in the literature as indicators of the soil collapse potential. Direct measurement of the magnitude of collapse, using laboratory and/or field tests, is essential once a soil showed indications of collapse potential. Treatment methods such as soil replacement, compaction control and chemical stabilization showed significant reduction in the settlement of collapsible soils. The design of foundations on collapsible soils depends on the depth of the soil, magnitude of collapse and economics of the design. Strip foundations are commonly used when collapsing soil extends to a shallow depth while piles and drilled piers are recommended in cases where the soil extends to several meters. This paper provides a comprehensive review of collapsible soils. These include the different types of collapsible soils, mechanisms of collapse, identification and classification methods, laboratory and field testing, treatment methods and guidelines for foundation design.

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