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New guidebook aims to make pedestrian crossings safer

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crosswalk.jpgPedestrian crossings are an important feature of the multimodal transportation system, enabling pedestrians and bicyclists to safely access destinations on either side of streets or highways.

To help Minnesota transportation agencies evaluate pedestrian crossings and determine where improvements are warranted, the Minnesota Local Road Research Board funded the development of a new guidebook for practitioners. The guidebook focuses specifically on uncontrolled pedestrian crossings, which aren’t controlled by a stop sign, yield sign, or traffic signal.

The new guidebook recommends when to install marked crosswalks and other enhancements based on a number of factors, including the average daily vehicle count, number of pedestrians, number of lanes, and average vehicle speed. It helps agencies rate a crossing for pedestrian service, and includes a flow chart and several worksheets to assist in data collection and decision making.

The guidebook is designed around an 11-step evaluation process that engineers can use to evaluate an uncontrolled pedestrian crossing location in a systematic way. Based on the results of the evaluation, users can identify what level of treatment is appropriate for their location, ranging from in-street crossing signs to overhead flashing beacons to traffic calming devices such as curb bump-outs.

The Minnesota Local Technical Assistance Program (LTAP), a part of CTS, hosted a workshop based on the guidebook on June 5. The workshop provided attendees with an overview of the step-by-step evaluation process. Attendees included city and county engineers, MnDOT staff, and other transportation professionals.

Read the full article in the July issue of Catalyst or download the guidebook on the Minnesota LTAP website.

Primary seat belt law continues to save lives, money

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seatbelt.jpgMinnesota’s primary seat belt law continues to save lives and reduce serious injuries more than four years after being passed, according to a study by researchers at the U of M’s Humphrey School of Public Affairs.

The study examined Minnesota crash data collected from June 2009 (when the law was implemented) through June 2013 and compared it to expected data based on crash trends over time. Findings indicate that there were at least 132 fewer deaths, 434 fewer severe injuries, and 1,270 fewer moderate injuries than expected during this time.

According to the researchers, the safety benefits of the law translate into a savings of at least $67 million in avoided hospital charges, including nearly $16 million in taxpayer dollars that would have paid for Medicare and Medicaid charges.

The study was sponsored by the Minnesota Department of Public Safety and led by Humphrey School research fellow Frank Douma and Nebiyou Tilahun, a U of M graduate now on the faculty at the University of Illinois-Chicago.

The researchers also examined seat belt use data and survey results that measured support for the law. Findings show that support increased from 62 percent just before the law was passed to more than 70 percent in 2013, while the percentage of Minnesotans buckling up was at an all-time high of nearly 95 percent in 2013. This shows that some people are wearing their seat belts even though they don’t support the law.

When this increased seat belt use is combined with the reduction in fatalities and injuries, it further demonstrates that people are surviving—and even walking away from—crashes that may have had different results if the primary seat belt law had not been in effect.

Read the full article in the June issue of CTS Catalyst.

When it comes to crashes, right-angle collisions are among the most dangerous for vehicle occupants. These crashes often occur at stop-controlled intersections when drivers fail to stop, and traffic engineers are increasingly installing flashing LED stop signs—normal octagonal stop signs with flashing lights mounted on the corners—in an attempt to improve intersection safety.

A study by researchers from the U’s civil engineering department and Minnesota Traffic Observatory aims to give traffic engineers a clearer picture of the safety benefits of flashing LED stop signs. The research team conducted a two-pronged investigation of the signs’ safety effects: a statistical study to estimate crash reduction and a field study looking at drivers’ behavior changes after the installation of a flashing LED stop sign.

For the statistical study, the team compared the frequency of crashes after the installation of flashing LED stop signs at 15 intersections with a prediction of what the crash frequency would have been without the signs. Findings estimate that the installations reduced right-angle crashes by about 42 percent.

For the field study, researchers collected video data before and after the installation of a flashing LED stop sign in Chisago County, Minnesota. They then analyzed the video to determine driver stopping behavior and vehicle deceleration rates.

According to principal investigator Professor Gary Davis, there was no change in the proportion of clear stops to clear non-stops when drivers didn’t encounter opposing traffic. However, the proportion of clear stops increased after installation of the sign when opposing traffic was present.

The team used their findings to create a decision-support tool that can help traffic engineers decide where to place flashing LED stop signs. The tool can be used to determine whether right-angle crashes are a problem at a selected intersection and to predict the crash reduction expected from installing the flashing sign.

Read the full article in the May issue of Catalyst.


Illustration: J. David Thorpe

Access to emergency medical services (EMS) following a serious crash is a long-standing rural safety problem in the United States. Since EMS service is based on population density, rural areas are often underserved, resulting in higher fatality rates per rural mile traveled.

In an effort to improve the effectiveness of EMS response and care coordination in these rural areas, researchers at the University of Minnesota and Claremont Graduate University have conducted a pilot study of the CrashHelp system in central Minnesota. The study, completed in partnership with the Central Minnesota Regional Trauma Advisory Committee, was funded by the Minnesota Departments of Transportation and Health as part of the Minnesota Toward Zero Deaths program.

CrashHelp is a smartphone-based system that allows emergency responders to collect multimedia data about crash victims on-scene and send it directly into emergency rooms. The information gives hospitals advance notification of crash severity and helps them best prepare for a patient’s arrival.

Between July 2012 and June 2013, CrashHelp was implemented and tested at Cuyuna Regional Medical Center in Crosby, Tri-County Hospital in Wadena, and the ambulance providers that serve these facilities.

During the pilot, more than 20 paramedics used CrashHelp to report on nearly 400 incidents, with overall positive results. Findings indicated that the system helped improve EMS data collection, communication between EMS personnel and the hospitals’ emergency departments, and decision-making by hospital personnel.

For emergency room staff, the information collected using CrashHelp was especially valuable for preregistering patients and assembling medical teams prior to a patient’s arrival—both of which allowed patients to get treated more quickly.

The pilot study also revealed that deeper integration of CrashHelp with existing trauma workflows, EMS policies and procedures, and existing electronic patient care report and health record systems would be essential for the sustained use and value of the system.

Read the full article in the April issue of Catalyst.


The discussion and debate about automated speed enforcement in many states—including Minnesota—is both complex and puzzling. On one hand, studies have shown that automated speed enforcement (ASE) increases roadway safety when deployed in certain settings, and public opinion polls show Minnesotans overwhelmingly support ASE in certain locations.

On the other hand, only 14 states and Washington, D.C., employ ASE; Minnesota is one of the 36 states that do not use automated speed enforcement. The perceived lack of public support is often cited as the primary reason ASE isn’t used in more states.

Prompted by the gap in Minnesota between state policy and the safety benefits and strong support for ASE, researchers at the Humphrey School of Public Affairs designed a study to investigate scenarios for an ASE pilot program in work and school zones in Minnesota.

First, the research team documented the legal and political environment surrounding ASE in Minnesota and analyzed available data for speed-related crashes in Minnesota school and work zones. Next, the researchers investigated and cataloged the possible solutions to a number of considerations and questions involved in developing an ASE pilot project.

Finally, researchers set out to develop a “blueprint” of preferred scenarios for ASE in Minnesota—and came face-to-face with several obstacles, such as making decisions about design elements while weighing difficult political and policy issues surrounding public acceptance, operational challenges and cost issues, and effectiveness.

Despite these obstacles, policy experts say an ASE program in Minnesota is possible if government stakeholders and policymakers agree that ASE is a worthwhile investment.

Read the full article in the April issue of Catalyst.


The new Roadway Safety Institute, a $10.4 million regional University Transportation Center (UTC) established in late 2013, will conduct a range of research, education, and technology transfer initiatives related to transportation safety. Led by the University of Minnesota, the two-year consortium will develop and implement user-centered safety solutions across multiple modes.

The Institute will be a focal point for safety-related work in the region, which includes Minnesota, Illinois, Indiana, Michigan, Ohio, and Wisconsin. Other consortium members are the University of Akron, University of Illinois at Urbana-Champaign, Southern Illinois University Edwardsville, and Western Michigan University.

Max Donath, professor of mechanical engineering at the U of M, serves as the new Institute’s director. In this month’s Catalyst, Donath shared his vision for the Institute.

According to Donath, the Institute will focus on addressing regional traffic safety priorities, educating the public, and attracting more professionals to the safety workforce by connecting with students.

Research topics will focus on two key areas, Donath said: high-risk road users and traffic safety system approaches. The goal of this work is to prevent the crashes that lead to fatalities and injuries on the region's roads.

One unique Institute effort will involve working with American Indian communities in the region to explore and address the unusually high number of motor vehicle crash fatalities on tribal lands.  "Our research will work to better understand why this is happening and to develop more effective solutions," Donath said.

Read the full Q&A in the April issue of Catalyst.


Along with warmer temperatures, April is a month to celebrate transportation, with Distracted Driving Month, National Bike to Work Day, and National Work Zone Awareness Week, which ends today.

University of Minnesota researchers have focused on work zone safety in a number of research projects. One current project is sponsored by the Minnesota Department of Transportation (MnDOT) and led by civil engineering researcher Chen-Fu Liao. The goal of the project is to develop a smartphone app to assist pedestrians with visual impairments to navigate around work zones.

MnDOT to guide visually impaired through work zones with an app
KSTP, April 9, 2014

Other projects include:

See the full list of U of M work zone safety research reports and projects on the CTS website.

Distracted driving: texting and beyond

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By Janet Creaser

teen.jpgMany drivers are likely to associate distracted or inattentive driving with cell phone usage, such as making calls or texting. Distraction due to calling and texting gets a lot of media attention and has inspired lawmakers to take notice. In Minnesota, texting is illegal for all drivers and making cell phone calls of any types, such as using a hands-free link through a vehicle or Bluetooth device, is illegal for teen drivers under the age of 18. However, cell phone use is just one of the more obvious forms of driver distraction. Driver distraction can be visual, cognitive, manual, or a combination of all three.

Texting involves all three forms of distraction: visual (looking at the phone and not the road), cognitive (mentally composing the message instead of processing roadway information), and manual (manipulating the phone keyboard instead of the steering wheel). This is why texting is considered to be a significant risk factor for drivers and why laws banning texting are becoming increasingly common in the U.S. Other tasks that involve visual and/or manual distraction include interacting with the radio, a navigation system, a mobile device such as an iPod, reading, eating and drinking. Although not all forms of distraction are equally distracting, all can be dangerous under certain circumstances.

Cognitive distraction can be more difficult for drivers to identify. Some forms of cognitive distraction include driving while preoccupied with other thoughts due to worry or stress, or when drivers end up “lost in thought.” Daydreaming or “being lost in thought” is estimated to be a factor in about 4% of crashes. Cognitive distraction can also occur during conversations with passengers or while interacting with a speech-activated interface in a vehicle (e.g., voice commands to make a call or send a text). When a parent turns around to talk to a child in the backseat, they are visually and cognitively distracted. In many cases involving cognitive distraction, a driver’s eyes are on the road but his or her mind is not, potentially resulting in impaired response times to driving events or hazards.

Driving researchers, practitioners, and safety agencies are all focused on better understanding the impact distracted or inattentive driving has on crash rates in order to identify countermeasures to reduce or prevent it. Distracted driving has become such a significant concern that the United States Department of Transportation (USDOT) has set up, a website devoted to distracted driving. And here at the University of Minnesota, our HumanFIRST Laboratory investigates causes of driver distraction and ways to mitigate them.   

Janet Creaser is a research fellow at the University's HumanFIRST Laboratory and a CTS Research Scholar. Her research interests include examining driver distraction and driver responses to new road safety interventions, the development of driver support systems, and the effect of age on driver behavior, including the unique differences and needs of teen and elderly drivers.

With freight traffic increasing on U.S. roadways, commercial truck drivers often struggle to find safe and legal places to park. If parking spaces are not available at a nearby rest area or truck stop, drivers may be forced to pull over in unsafe locations or continue driving and become dangerously fatigued. Drivers may also risk violating federal hours-of-service rules, which require them to rest after 11 hours of driving.

In response to this issue, a team from the Minnesota Department of Transportation (MnDOT), University of Minnesota, and American Transportation Research Institute
 is developing a system that can identify available truck parking spaces and communicate the information to drivers—helping them determine when and where to stop. System benefits include improved safety, reduced driver fatigue, and better trip management.

The system uses a network of digital cameras suspended above a parking area to monitor space availability. Image processing software developed by researchers at the U of M’s computer science and engineering (CS&E) department analyzes the video frames and determines the number of available spaces.

As part of a demonstration project funded by MnDOT and the Federal Highway Administration, the project team is installing the system at three MnDOT rest areas and one private truck stop on I-94 west and northwest of the Twin Cities.

The U of M research team first installed the system in late 2012 at the the Elm Creek Rest Area, two miles north of Interstate 494 on I-94. As of early 2014, the system has been installed at an additional rest area, and a third site is in progress. 

Next steps for the project include implementing several mechanisms that will communicate parking information to truck drivers. First, the team plans to install variable message signs along I-94 this spring. Also in the works are an in-cab messaging system and a website.

Overall results of the demonstration project will help the team determine whether this technology holds promise for use in other corridors throughout the nation.

Read the full article in the February issue of Catalyst.


In the not-too-distant future, your car will warn you if you’re getting drowsy, remember where potholes are on your route home, and apply the brakes at intersections. Advanced driver-assist systems combined with “big data” are moving us quickly to this day—offering the possibility to greatly reduce crashes or even make them a thing of the past.

At the CTS Fall Luncheon on December 3, Luca Delgrossi, director of driver assistance and chassis systems at Mercedes-Benz Research & Development North America, offered his perspective of new developments in this innovative technology.

Delgrossi said the next generation of driving technology focuses on preventing crashes altogether with the use of richer sets of sensors covering a broader space around cars, as well as new actuators that can control the vehicle. Sophisticated in-car networks exchange data from one component to another, creating more powerful systems as well as system redundancy for reliability.

There are many other opportunities to help drivers who are distracted or facing a complex situation. One system, for example, would help drivers stay awake during long trips. It builds a profile from data collected in the first 20 minutes; during the rest of the trip, it checks to see if the driver is deviating from this pattern—and if so, gives an alert to take a break.

Delgrossi also touched on the potential for vehicles to share data with each other, such as warnings of icy roads ahead.

Ultimately, the goal of the upcoming technology is to avoid crashes by allowing cars to take more and more control.

“Hands-off driving is coming," Delgrossi said. “We need to bring technology to perfection to do this. That’s what the industry is working on. We will see progress in the next five to seven years.

Read the full article in the January issue of Catalyst.

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