In the fall of 2022, a first-of-its-kind CAV pilot program called goMARTI (or, Minnesota’s Autonomous Rural Transit Initiative) was launched as a collaborative effort between numerous partners. The 18-month pilot offers free, on-demand rides to area residents and visitors using five autonomous shuttle vans (including three wheelchair-accessible vans) at 70 drop-off and pickup points within a 17-square-mile area. In this project, researchers documented lessons learned from the pilot, which included exploring the recent history of institutional and community engagement efforts regarding transportation in Itasca County and Grand Rapids, as well as the innovations and collaborations that took place to make the pilot’s implementation possible.

The Center for Transportation Studies will bring participants in this research together in a webinar on Friday, December 6, 2024, from 1:30–3:00 p.m. To register, go to Unlocking Autonomous Transportation Potential—Key Insights from the goMARTI Shuttle Pilot.

Blind spot monitoring, lane departure warnings and adaptive cruise control are among the functions of automated vehicles (AVs) with significant potential safety benefits. To accurately function, lane keep systems rely on camera-based sensors to detect pavement markings and help a vehicle track the roadway lanes. New research results increase understanding of pavement marking design qualities that optimize AV function.

Using two different camera systems and four different vehicle makes and models with a range of automated functions, researchers observed camera and vehicle tracking performance on roads with a variety of pavement marking characteristics. Results of this study and a companion project exploring human response to pavement marking variations led to recommendations for MnDOT to modify marking designs to work better for AVs as well as human drivers. Suggested changes include slightly changing the standard highway lane divider mark-to-gap ratio, widening stripes to 6 inches as allowable and delineating turn lanes and exit ramps with dotted lines.

Unintentional lane departure that occurs when drivers are speeding, distracted or drowsy poses a significant safety risk on roadways. Some higher-end vehicles have built-in lane departure warning systems (LDWS). But the technologies are not widely accessible, and their performance is limited when lane markings aren’t completely visible due to inclement weather.

The latest phase of an ongoing research project has refined a smartphone app that provides an audible warning if a vehicle drifts from its lane. The addition of GPS has improved the accuracy of the algorithms driving the system, and a user-friendly smart phone interface offers the potential of a widely accessible safety tool. Researchers will continue work to patent the app and coordinate with mapping companies to streamline its operation. Once available, Minnesota’s transportation agencies will encourage all drivers with smartphones to use it.

To learn more about this technology, join researchers in a free webinar on Thursday, November 14, 12:00 to 1:00 p.m. To register for the event, go to Stay in Your Lane: App to Warn Drivers of Unintentional Lane Departures.

Managing stormwater runoff is important to prevent flooding and associated safety risks, property damage and threats to water quality in Minnesota’s streams and lakes. Stormwater best management practices are used to help improve water quality and meet federal Clean Water Act regulations and must accommodate specific land use and management objectives. In response to over a decade of research and the evolution of stormwater management strategies, the Local Road Research Board (LRRB) developed a comprehensive update to the 2009 Stormwater Maintenance BMP Resource Guide.

The revised Stormwater BMP Inspection and Maintenance Resource Guide provides updated recommendations for traditional stormwater practices and presents new, innovative strategies to manage runoff. Investigators reviewed the stormwater literature and the Minnesota Stormwater Manual, a comprehensive living document managed by the Minnesota Pollution Control Agency that covers numerous general stormwater concepts and issues. Other LRRB research projects that explored the differences in runoff between rural and urban roads, stormwater pond management and related issues also informed the revisions. Additionally, the new guide contains a chapter on how to best meet stormwater management objectives based on targeted pollutants.

Thin, fiber-reinforced concrete pavements and overlays can be economical for low- and moderate-traffic volume roads. However, the thin coverage can’t accommodate dowel bars used in conventional thick concrete pavements due to transverse joint faulting between the concrete slabs. Currently available synthetic structural fibers can improve joint performance somewhat, but there is a need to design and develop fibers that will provide high joint performance and help mitigate transverse joint faulting when used at an affordable dosage.

In the initial phase of this National Road Research Alliance study, researchers determined the forces induced on the fibers because of vehicular and environmental loads and identified the characteristics that can most easily be changed in the concrete and/or fibers for the purpose of improved performance of thin concrete pavements and overlays.  In the next phase, the team will design and test the pavement-specific concrete mixture and fibers.

Sheila Hatchell, director of the MnDOT Library, retired in September after 17 years in that position. During her tenure, Sheila had many accomplishments. In 2010-2011, she oversaw the renovation of the library space, a project that received the American Library Association's John Cotton Dana Public Relations Award. In 2012, she co-authored Proving Your Library’s Value: A Toolkit for Transportation Libraries. Sheila led an initiative to make more library materials available digitally, an effort that became critical during the pandemic. The library team launched an eBooks collection and MnDOT Digital Library. Earlier this year, Sheila received the 2024 Professional Achievement Award from the Special Libraries Association after being nominated by her peers. We thank Sheila for her many contributions to MnDOT and wish her all the best in her retirement.