Automated vehicles (AVs) using advanced driver assistance systems depend on pavement markings to accurately track roadway lanes. While MnDOT continues to ensure human drivers easily and effectively detect and interpret various pavement markings, the agency also wanted to understand marking designs and characteristics that support AV functions. Field observations in different locations, during the day and at night, using different data collection methods allowed researchers to evaluate the impact of various pavement marking properties on AV lane-keeping functions. Results support MnDOT in producing pavement marking guidance that is responsive to changing needs.
Continue reading Pavement Markings to Support Automated VehiclesCategory Archives: Traffic and Safety
An Evaluation of Vehicle Identification Technology
To successfully manage the state road network, MnDOT needs a thorough understanding of the number and type of vehicles on the road. To obtain this information, the agency upgraded existing inductive loop infrastructure at select locations to enable these sensors to collect vehicle classification data. This project evaluated the accuracy of the inductive loop upgrade and its life cycle costs to determine its viability for future use on Minnesota roads.
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Refining Max-Pressure Traffic Signal Control to Improve Traffic Flow
Effective traffic signal control technologies facilitate optimal traffic flow and travel time. Building on previous research, this project made significant progress toward field implementation of a novel adaptive signal control technology. This research phase demonstrated the max-pressure traffic signal algorithm can successfully integrate into Hennepin County traffic signal hardware and respond to changing traffic conditions in real time, providing confidence to move to the next step and test the system in the field.
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Developing Technology to Prevent Vehicles from Running Red Lights
Crashes that result from vehicles driving through red lights are often very serious because they are typically right-angle or side-impact crashes. While newer vehicles have many standard safety features such as lane departure warning and brake assistance systems to support drivers, they do not have technologies to help prevent driving through red lights. This project developed an algorithm that integrated traffic light phasing information with GPS data to warn drivers when they were approaching a red light, providing valuable driver assistance and improving traffic safety and efficiency.
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Comparing the Effectiveness of No Right Turn on Red Sign Types at Traffic Signals
Preventing right turns on red at traffic signals is a generally effective pedestrian safety measure. But when pedestrians are absent, allowing right turns on red can improve traffic flow. Unlike static signs that prohibit right turns on red, dynamic No Right Turn on Red (NRTOR) signs can be activated when pedestrians are present. Comparing driver compliance with dynamic and static signs indicated that each sign type may have its own benefits.
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Assessing Reliability and Resilience on Freeway Corridors
Drivers and businesses benefit from a freeway network that is predictable and able to withstand disturbances such as construction, incidents and poor weather. To provide a high level of service on freeways, traffic managers monitor and assess traffic flows and speeds under various conditions. In this project, investigators analyzed and identified the most vulnerable portions of the Twin Cities freeway network and enhanced an analysis tool to provide better estimates of travel-time reliability and operational resilience.
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Examining Driver Preferences for Lane Line Patterns and Widths
Pavement markings that clearly delineate lanes are important for reducing crashes and improving the safety of drivers. The configurations of these pavement markings—primarily the width and length of the line and the spacing of broken lines—vary from state to state. This project identified driver preferences for pavement marking patterns and widths, which can increase visibility and improve safety.
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New Project: Roundabouts, J-Turns, etc. – Understanding Their Economic Impacts
Roundabouts and J-turns have consistently shown significant improvements in safety and traffic flow in Minnesota and across the U.S. Still, some community residents and businesses oppose replacing traditional intersections with alternative intersections like roundabouts or J-turns.
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New Smartphone App Uses GPS Technology to Warn Drivers of Lane Departures
Preventing vehicles from drifting out of traffic lanes is a top safety priority for transportation officials. An ongoing research project has produced a smartphone app that alerts drivers when their vehicles drift from a lane. The current phase of the project improved upon earlier versions of the app by adding GPS and significantly increasing the effectiveness of lane departure detection.
Designing Channelized Right-Turn Lanes to Increase Pedestrian and Cyclist Safety
The use of channelized right-turn (CRT) lanes at intersections can improve driver safety and traffic mobility but can be challenging for bicyclists and pedestrians, particularly those with sight or other impairments. This project examines the current practice of CRTs to identify design solutions and mitigation strategies to better accommodate the safety and accessibility needs of all road users.
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Crossroads 