Effects of Full Matrix Color Changeable Message Signs on Legibility and Roadway Hazard Visibility

2017 ◽  
Vol 2617 (1) ◽  
pp. 9-18
Author(s):  
Susan T. Chrysler ◽  
Paul J. Carlson ◽  
Brad Brimley ◽  
Eun Sug Park
Keyword(s):  
Object Detection ◽  
Travel Time ◽  
Traffic Control ◽  
Detection Distance ◽  
Full Matrix ◽  
Safety Message ◽  
Object Locations ◽  
Changeable Message Signs ◽  
Blue Background ◽  
Message Signs

Transportation agencies are considering public–private partnerships as they struggle to fund infrastructure and operations improvements. The national Manual on Uniform Traffic Control Devices (MUTCD) allows acknowledgments of private sponsors on static signs. The legibility and visibility impacts of including logos of sponsors on changeable message signs (CMSs) were examined. Thirty drivers participated in a closed-course study during daytime and nighttime conditions. Full-sized full matrix color LED signs were used to display travel time and safety reminder messages with and without sponsor acknowledgment logos. Single- and dual-phase messages were tested. The measures of effectiveness were legibility distance for target words on the signs and roadway hazard object detection distance. Legibility distances of the CMS messages were notably greater than those of retroreflective traffic signs and well above the MUTCD threshold of 30 ft/in. During the day, the median legibility index was approximately 60 ft/in. At night, the index was approximately 45 ft/in. Sponsor logos had no significant effect on the legibility distances of travel time signs. Sponsor logos had a small effect on the legibility distance of safety message signs with a blue background but not on those with a black background. The use of sponsor logos marginally affected object detection for certain object locations. The results of this study, coupled with an earlier driving simulation evaluation showing no cognitive distraction due to logos, support the use of sponsorship acknowledgment signs on CMSs. An open road evaluation is planned before statewide implementation is enabled.

Evaluating Speed-Reduction Strategies for Highway Work Zones

2003 ◽  
Vol 1824 (1) ◽  
pp. 44-53 ◽  
Author(s):  
Chunyan Wang ◽  
Karen K. Dixon ◽  
David Jared
Keyword(s):  
Traffic Control ◽  
Statistical Tests ◽  
Work Zones ◽  
Control Zone ◽  
Novelty Effect ◽  
Speed Reduction ◽  
Reduction Strategies ◽  
Changeable Message Signs ◽  
Message Signs ◽  
Over Time

Research was conducted to identify the potential of fluorescent orange sheeting, innovative message signs, and changeable message signs with radar for reducing speeds in highway work zones. The study investigated the effect of each strategy immediately after implementation (immediate effect) as well as several weeks after implementation (novelty effect). In addition to the overall effect of each strategy on all vehicles, the study included the effect on specific vehicle types during various lighting conditions. The researchers collected traffic data before, immediately after, and 2 or 3 weeks after implementation of each strategy (3 consecutive weeks for the changeable message sign). They collected data upstream of the temporary traffic-control zone, in the advancewarning area, and adjacent to the active work area. The researchers used various statistical tests to evaluate the significance of speed changes from phase to phase and adjusted vehicle speeds with the upstream speed changes over time. The study indicated that fluorescent orange sheeting and innovative message signs help reduce speeds at highway work zones (with diminished influence over time). Moreover, both strategies influence vehicle speeds more during the day than at night. Drivers of passenger vehicles tended to decrease their speeds more than did truck drivers. Changeable message signs with radar significantly reduced the vehicle speeds in the immediate vicinity of the sign and did not demonstrate a novelty effect.

scholarly journals Deep Learning-Based Object Detection, Localisation and Tracking for Smart Wheelchair Healthcare Mobility

2020 ◽  
Vol 18 (1) ◽  
pp. 91
Author(s):  
Louis Lecrosnier ◽  
Redouane Khemmar ◽  
Nicolas Ragot ◽  
Benoit Decoux ◽  
Romain Rossi ◽  
...  
Keyword(s):  
Object Detection ◽  
Object Tracking ◽  
Indoor Environment ◽  
Distance Estimation ◽  
Depth Estimation ◽  
Detection Algorithm ◽  
Use Case ◽  
Detection Distance ◽  
Detection Depth ◽  
Sort Algorithm

This paper deals with the development of an Advanced Driver Assistance System (ADAS) for a smart electric wheelchair in order to improve the autonomy of disabled people. Our use case, built from a formal clinical study, is based on the detection, depth estimation, localization and tracking of objects in wheelchair’s indoor environment, namely: door and door handles. The aim of this work is to provide a perception layer to the wheelchair, enabling this way the detection of these keypoints in its immediate surrounding, and constructing of a short lifespan semantic map. Firstly, we present an adaptation of the YOLOv3 object detection algorithm to our use case. Then, we present our depth estimation approach using an Intel RealSense camera. Finally, as a third and last step of our approach, we present our 3D object tracking approach based on the SORT algorithm. In order to validate all the developments, we have carried out different experiments in a controlled indoor environment. Detection, distance estimation and object tracking are experimented using our own dataset, which includes doors and door handles.

Does Displaying Safety Messages on Dynamic Message Signs have Measurable Impacts on Crash Risk?

2021 ◽  
pp. 036119812110444
Author(s):  
Megat-Usamah Megat-Johari ◽  
Nusayba Megat-Johari ◽  
Peter T. Savolainen ◽  
Timothy J. Gates ◽  
Eva Kassens-Noor
Keyword(s):  
Negative Binomial ◽  
Driver Behavior ◽  
Field Research ◽  
Crash Risk ◽  
Traffic Crashes ◽  
Crash Data ◽  
Safety Issues ◽  
Dynamic Message Signs ◽  
Safety Message ◽  
Message Signs

Transportation agencies have increasingly been using dynamic message signs (DMS) to communicate safety messages in an effort to both increase awareness of important safety issues and to influence driver behavior. Despite their widespread use, evaluations as to potential impacts on driver behavior, and the resultant impacts on traffic crashes, have been very limited. This study addresses this gap in the extant literature and assesses the relationship between traffic crashes and the frequency with which various types of safety messages are displayed. Safety message data were collected from a total of 202 DMS on freeways across the state of Michigan between 2014 and 2018. These data were integrated with traffic volume, roadway geometry, and crash data for segments that were located downstream of each DMS. A series of random parameters negative binomial models were estimated to examine total, speeding-related, and nighttime crashes based on historical messaging data while controlling for other site-specific factors. The results did not show any significant differences with respect to total crashes. Marginal declines in nighttime crashes were observed at locations with more frequent messages related to impaired driving, though these differences were also not statistically significant. Finally, speeding-related crashes were significantly less frequent near DMS that showed higher numbers of messages related to speeding or tailgating. Important issues are highlighted with respect to methodological concerns that arise in the analysis of such data. Field research is warranted to investigate potential impacts on driving behavior at the level of individual drivers.

Dynamic control cycle speed limit strategy for balanced reduction of travel time and emissions

2021 ◽  
Vol 35 (09) ◽  
pp. 2150153
Author(s):  
Minghui Ma ◽  
Yaozong Zhang ◽  
Shidong Liang
Keyword(s):  
Travel Time ◽  
Traffic Control ◽  
Dynamic Control ◽  
Transmission Model ◽  
Cell Transmission Model ◽  
Vehicle Exhaust ◽  
Environmental Benefit ◽  
Multiple Control ◽  
Total Travel Time ◽  
Co Emission

The vehicle exhaust has been one of the major sources of greenhouse gas emissions. With an increase in traffic volume, it has been found that the introduced intelligent traffic control is necessary. This paper investigated a novel VSL strategy considering the dynamic control cycle to improve the traffic efficiency and environmental benefit on freeway. An extension of the cell transmission model (CTM) was used to depict the traffic characteristics under VSL control, and integrated with the microscopic emission and fuel consumption model VT-Micro to estimate the pollution emission of each cell. The VSL strategy was designed to provide multiple control cycles with different length to adjust the scope of VSL changes, furthermore, a probability formula was developed and used to determine the optimal quantity of control cycles to reduce the computational complexity of controller. An objective optimization function was formulated with the aim of minimizing total travel time and CO emission. With simulation experiments, the results showed that the proposed VSL strategy considering the dynamic control cycle outperformed uncontrolled scenario, resulting in up to 8.4% of total travel time reductions, 26.7% of delay optimization, and 14.5% reduction in CO emission, which enhanced the service level of freeway network.

New Intelligent Transport Systems Applications in Europe to Improve Bus Services

2002 ◽  
Vol 1791 (1) ◽  
pp. 85-91 ◽  
Author(s):  
Nick Hounsell ◽  
Graham Wall
Keyword(s):  
Public Transport ◽  
Traffic Control ◽  
Urban Traffic ◽  
Transport Systems ◽  
Intelligent Transport Systems ◽  
Bus Priority ◽  
Intelligent Transport ◽  
Message Signs ◽  
Investment Process ◽  
Bus Services

Applications of information technology are expanding rapidly across all modes of transport, under the general heading of intelligent transport systems (ITS). For bus-based public transport, a cluster of applications has been developed that can help improve the efficiency and performance of buses on the street, thus helping to provide a real transport alternative to the private car. An initial summary of a range of such ITS examples in Europe is provided, including automatic vehicle location (AVL), bus priority in traffic control systems, automatic ticketing systems, automatic camera enforcement systems, and variable message signs. Then the focus shifts to one area where activity is most pronounced—the implementation of AVL systems and their integration with urban traffic control (UTC) systems. A review of typical AVL/UTC systems operational in Europe is then presented through the identification of some eight alternative architectures and associated system characteristics, such as the technologies used and the location of bus priority “intelligence.” This is followed by a summary of examples from cities in Europe that have implemented these architectures, together with typical results illustrating the effectiveness of these systems. The diversity of architectures, technologies, and systems is recognized as beneficial in providing customer choice, but can generate a significant difficulty for decision makers in local authorities wishing to invest in public transport ITS technologies. A concluding discussion lists some of the key issues involved in this investment process.

scholarly journals ELECTRONIC TRAFFIC SIGNS: THE INTERPLAY BETWEEN HYBRID AND FULL MATRIX E-SIGNS

2016 ◽  
Author(s):  
Antonio Lucas-Alba ◽  
Ana Hernando Mazón ◽  
María Teresa Blanch Micó ◽  
Diego Gutiérrez Pérez ◽  
José Ignacio Echeverría Villaspí ◽  
...  
Keyword(s):  
Experimental Design ◽  
Communication System ◽  
Repeated Measures ◽  
Reading Strategy ◽  
Top Down ◽  
Full Matrix ◽  
Road Signs ◽  
Electronic Displays ◽  
Main Factors ◽  
Message Signs

Road signs constitute a complex and growing communication system where different elements (pictograms, shapes, texts, etc.) are combined following different strategies. In this paper we have confronted drivers with a number of messages (congestion or road works, before, between, after location/s) developed as an adaptation of Advance Location Signs (class G, 1c in the 1968 Convention) to electronic displays. We manipulate two main factors a) the reading strategy (top-down vs. bottom-up) and the type of matrix display (hybrid, dissociating pictogram and text, vs. full matrix), in a repeated measures experimental design. The time taken to answer and the response given (correct, incorrect) was measured for each of the 24 message-blocks. Results show that the organization of the elements displayed is a key determinant for driver comprehension. Further thoughts on the need to understand the interplay between the formats adopted by static vs electronic message signs are provided.DOI: http://dx.doi.org/10.4995/CIT2016.2016.3327

scholarly journals Delay Measurement of Manually Controlled Intersection Using GPS

2014 ◽  
Vol 8 (1) ◽  
pp. 130-135
Author(s):  
S. Nithya ◽  
D. Senthurkumar ◽  
K. .Gunasekaran
Keyword(s):  
Travel Time ◽  
Traffic Control ◽  
Weather Conditions ◽  
Heterogeneous Traffic ◽  
Gps Data ◽  
Peak Period ◽  
Control Delay ◽  
Average Travel Time ◽  
Vehicle Acceleration ◽  
Acceleration And Deceleration

The travel time studies are one of the most important measures used for evaluating the performance of road networks. The Global Positioning System (GPS) is a space-based system that provides position and time information in all weather conditions. GPS data could be used to obtain the values of traffic control delay, vehicle queue, average travel time and vehicle acceleration and deceleration at intersections.The task of estimation of delay becomes complex if it is performed for intersections carrying heterogeneous traffic and that to for over saturated conditions. Most of the urban signalized intersections are manually controlled during peak hours. GPS device fitted in a vehicle was run repeatedly during morning peak period and the period during which vehicles were allowed to cross the intersection was recorded with video graphic camera. The attempt to identify the control delay with the GPS data from the test vehicle while crossing manually operated major intersection is presented in this paper.

scholarly journals Visualizations of Travel Time Performance Based on Vehicle Reidentification Data

2017 ◽  
Vol 2646 (1) ◽  
pp. 84-92 ◽  
Author(s):  
Stanley Ernest Young ◽  
Elham Sharifi ◽  
Christopher M. Day ◽  
Darcy M. Bullock
Keyword(s):  
Travel Time ◽  
Performance Measures ◽  
Traffic Control ◽  
Cumulative Distribution ◽  
Travel Time Reliability ◽  
Travel Times ◽  
Traffic Patterns ◽  
Before And After ◽  
Vehicle Reidentification ◽  
Arterial Performance

This paper provides a visual reference of the breadth of arterial performance phenomena based on travel time measures obtained from reidentification technology that has proliferated in the past 5 years. These graphical performance measures are revealed through overlay charts and statistical distribution as revealed through cumulative frequency diagrams (CFDs). With overlays of vehicle travel times from multiple days, dominant traffic patterns over a 24-h period are reinforced and reveal the traffic behavior induced primarily by the operation of traffic control at signalized intersections. A cumulative distribution function in the statistical literature provides a method for comparing traffic patterns from various time frames or locations in a compact visual format that provides intuitive feedback on arterial performance. The CFD may be accumulated hourly, by peak periods, or by time periods specific to signal timing plans that are in effect. Combined, overlay charts and CFDs provide visual tools with which to assess the quality and consistency of traffic movement for various periods throughout the day efficiently, without sacrificing detail, which is a typical byproduct of numeric-based performance measures. These methods are particularly effective for comparing before-and-after median travel times, as well as changes in interquartile range, to assess travel time reliability.

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