Safety with a Rumble

by Matt Mann, Research Program Coordinator

Centerline rumble strips have been shown to reduce lane departure crashes by as much as 25% on rural roads, and are now being installed on undivided, rural, two-lane highways in Massachusetts as appropriate.

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The sinusoidal rumble strip uses a wave-shaped rumble strip to create the noise and vibration necessary to alert the driver. (Road and Bridges, 4/3/2017)

Improving safety, at a low-cost, can reduce crashes and save lives. In the U.S., 60% of crashes on rural roads result in a fatality. Of these fatal crashes, approximately 90% are on two-lane roads. Lane departure crashes from vehicles crossing over the centerline on undivided, two-lane, rural roads have been proven to decrease with the installation of centerline rumble strips (CLRS). This reduction can be as high as 25% along certain rural roads, and even higher when CLRS are installed along with shoulder rumble strips (SRS).

Many factors contribute to drivers crossing over the center yellow line, including speeding, fatigue, and drowsiness, and distracted driving. Some common techniques on the roads now that try to mitigate lane departures and improve safety include, but are not limited to centerline and edge line pavement lane markings, higher retroreflectivity of traffic signs (for day and nighttime visibility), and vertical reflective panels. All of these have had some success. A number of studies, however, have shown CLRS to be more effective along certain rural sections of highways, in decreasing lane departures.

The purpose of CLRS is to prevent vehicles from crashing head-on or sideswiping each other. Vehicles tend to veer outside of their lane on all types of roadways, especially on undivided, two-lane rural highways where cross-over crashes are most common. CLRS can also act as a traffic calming tool. Similar in design to the rumble strips on the shoulders of Interstates and other limited access highways, CLRS are located along the centerline. With either placement, the objective of the rumble strips is to alert inattentive drivers that they are veering outside of their lane, and ideally help them correct this action before a crash occurs.

The main reason for CLRS’ effectiveness is their design, specifically the vibrations and noise when tires cross over them. However, this noise has also been a major reason why CLRS are not used on more roads. Abutters and businesses have complained about CLRS being too loud as vehicles cross over them. California Department of Transportation (CalTrans) and Minnesota DOT (MnDOT) have conducted research on creating effective, quieter CLRS. MnDOT has developed the sinusoidal wave-shaped rumble strip. Some study results have shown a decrease in noise levels outside the vehicle, as vehicles cross over these sinusoidal rumble strips, while the CLRS still maintain the effectiveness by alerting drivers of lane departures. In addition to noise, another concern of CLRS is the potential reduction of visibility of the centerline yellow strip, though, in a survey by the Insurance Institute for Highway Safety, some respondents reported that the visibility of the centerline yellow strip in the rain was better over CLRS than on flat pavement.

MassDOT, along with other DOTs, continues to develop and implement CLRS on their rural, undivided, two-lane highways. MassDOT currently considers implementing CLRS on an as needed basis. Decisions about where to install CLRS are based on a couple of variables, including lane departure crash data and land use (regarding the noise factor). As discussed with Bonnie Polin, MassDOT Highway Division Manager of Highway Safety, CLRS were recently included in a paving project along sections of Route 140 in Gardner and Winchendon. CLRS are easier and more cost effective to install when a roadway is being re-paved as was the case along Route 140. As MassDOT updates its Strategic Highway Safety Plan, CLRS are referenced as a safety measure to prevent lane departures.  MassDOT will continue to support and install CLRS on their secondary roads, where appropriate.

 

 

Improving Safety in the Work Zone

by Courtney Murtagh, Intern, and Tracy Zafian, Research Fellow

In 2015, 860 vehicle crashes in roadway work zones were reported in Massachusetts, and over 96,000 crashes in work zones nationwide. Researchers and state officials have been examining the causes, and options for reducing work zone crashes, injuries, and fatalities.

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Work zone area on the MassPike during the removal of toll booths. (Boston Herald, photo credit Angela Rowlings)

With summer in full swing, we find ourselves in the midst of another road infrastructure improvement and repair season. Drivers may have noticed an increase in the number of work zones along state and town highways in Massachusetts. During these warmer months, drivers need to take extra precautions for their safety and the safety of road construction workers.

The Federal Highway Administration (FHWA) recorded a total of 765 work zone traffic fatalities nationwide in 2016, in the Fatality Analysis and Recording System (FARS). This is a 7% increase from 2015.  Many of these fatalities (83%) were of motor vehicle drivers or passengers, the remainder were pedestrians, bicyclists, and other non-motorists. Relatedly, the U.S. Bureau of Labor Statistics found that there were 143 deaths of road workers at construction sites. This count overlaps with the FARS figures. Forty percent of the traffic fatalities in work zones are from rear-end collisions, as vehicles fail to slow down adequately approaching and traveling through the work zones.

According to the FHWA, there were 96,626 crashes in work zones in 2015, a 42% increase since 2013. The same study showed that nationwide there were on average 70 work zone traffic crashes with injury per day that year.

For Massachusetts, the State Police reported 860 work zone crashes for 2015. The data show that work zone crashes occur most often between May and September, during the day, and on a Tuesday, Wednesday or Thursday. Drivers should be especially cautious and attentive when traveling through work zones, as construction workers may be present and as drivers may be asked to stop.

Speed limits in work zones are set according to state law. The law allows for the doubling of speeding fines in work zone areas.

In 2016, MassDOT created a Work Zone Safety Task Force to consider innovative engineering and technology-related solutions for better work zone safety. The Work Zone Task Force implemented some new safety features in work zones in 2017, including portable rumble strips, and flashing blue LED lights in work zones to simulate a police presence and get drivers to reduce their speed. Another type of technology being considered are smart cones, which communicate with construction workers to warn them when potential threats, such as a speeding or erratically driving vehicle, are approaching a work zone. A previous Innovative Outlook article discussed some of the technology options for improved work zone safety in more detail.

Another potential way to reduce work zone crashes is the ‘zipper’ merge. The zipper occurs when two lanes of traffic equally merge into one. Research conducted at UMass Amherst by Dr. Michael Knodler and Civil Engineering graduate students Alyssa Ryan and Francis Tainter has been investigating the potential use of zipper merges to help improve traffic safety. UMass Amherst’s zipper merge research was discussed in the March and April 2018 Innovative Outlook. An FHWA analysis of FARS crash fatality data found improper merging to be the second most dangerous driving maneuver, behind only inattentive driving. The zipper merge is hypothesized to improve both roadway safety and efficiency, including in work zone areas.

Massachusetts is Meeting Climate Change Head On

by Matt Mann, Reseach Program Coordinator

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State Street, Boston – City Lab

As weather events become more extreme, MassDOT and Massachusetts communities, especially those on the coast, recognize their infrastructure is vulnerable. Coastal cities and towns are currently grappling with the extreme climate impacts of higher temperatures, increased extreme precipitation and greater amounts of sea level rise. All of these impacts are not new, they have slowly been occurring over the past century.  It is predicted these changes will accelerate and increases will happen over a shorter length of time (e.g. by 2030, the sea level could rise by 4”-8” (BRAG Report, 2016)).

MassDOT and Climate Ready Boston presented at the April 2018 MassDOT Innovation and Mobility Exchange on the impacts to transportation assets and infrastructure, and strategies to better accommodate climate change. Mia Mansfield, Climate Ready Boston, presented on goals to guide Boston’s future growth:

  • Goal 1: Provide quality of life in accessible neighborhoods
  • Goal 2: Drive inclusive economic growth
  • Goal 3: Promote a healthy environment and adapt to climate change, and
  • Goal 4: Invest in infrastructure, open space and culture

Associated with these goals are planning and implementation projects for creating resilient infrastructure and buildings, preparing communities, and protecting shorelines. The feedback from the public outreach on what types of flood ready improvements the public would like to see included expanding open space, berm development, and flood walls. Project areas Climate Ready Boston has focused on are East Boston, Charlestown, and South Boston. Mansfield spoke about this initiative saying, “The resiliency strategy embraces layered flood control and integrated green infrastructure measures that mitigate the effects of climate change, and create social, environmental, and economic benefits and value to the people of East Boston and Charlestown and to all who share in the health of the city and the harbor.”

The existing transportation assets will be impacted by more flash floods, landslides, and flooding. Further, increased precipitation could have adverse impacts on the infrastructure that helps move the water, especially on culverts. Hongyan Oliver, MassDOT Office of Transportation Planning, and Chris Dorney, WSP USA, presented on MassDOT’s multi-year statewide Climate Adaptation Vulnerability Assessment study. This study aims first to identify a prioritized set of MassDOT transportation assets throughout the Commonwealth that is at high risk for future inland flooding, and second to provide actionable scientific information for adaptive strategies, and future capital and project planning. This second goal begins on a broader planning level and then is developed through a detailed analysis of vulnerable assets. One challenge is mapping statewide future floodplains where vulnerable assets are located. With this challenge in mind, MassDOT is currently conducting a pilot mapping study on a watershed in western Massachusetts. The approach is to prepare georeferenced data, assign slopes, calculate current peak flows and 100-year flows, elevations, and floodplains, and evaluate the asset exposure. Procedures for floodplain mapping will include developing an instruction manual, applying the data management protocol, and automating parts of the process for efficiency.

Next steps after that will include training additional MassDOT staff on the procedures, and applying the pilot study procedures and lessons learned from all other watersheds in the state and sharing the results and data with stakeholders.  Eventually, this important information and these strategies can then be incorporated into MassDOT’s project prioritization, capital planning, asset management system, and emergency preparedness procedures.

Prospects and Challenges for Automated and Autonomous Vehicles

by Tracy Zafian, Research Fellow

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May 2018: A car driven with Tesla’s Autopilot driver assist system crashed into a parked police car. The Autopilot system is designed to be used on limited access highways, not on roadways such as this one. (Source: Uncredited/AP/Rex/Shutterstock)

In March 2018, an Uber Volvo operating in automated driving mode, with a driver at the wheel, hit and killed a pedestrian in Arizona. It was the first autonomous vehicle (AV)-related pedestrian fatality. There have been other crashes involving autonomous test vehicles and additional fatalities involving lower-level automated vehicles since.  Also in March, a driver in California was killed when his Tesla, in autopilot mode, crashed into a concrete highway lane divider and caught fire. Last month, a Tesla, in autopilot mode, crashed into a parked firetruck in Utah and into a parked police car in California.  Injuries were minor in these instances.

All of these crashes have occurred while there has been a driver at the wheel making decisions about when to use and disengage the automated driving assist system. As reported in a USA Today article, following the Utah firetruck crash, Tesla issued a statement saying, “When using Autopilot, drivers are continuously reminded of their responsibility to keep their hands on the wheel and maintain control of the vehicle at all time,” and, “Autopilot is designed for use on highways that have a center divider and clear lane markings.” These conditions are not always met when crashes occur; for example, the driver in the Utah crash admitted to being distracted by their phone before the crash. From the National Transportation Safety Board’s preliminary findings from investigating the Uber pedestrian crash, there was no warning given to the safety driver before the crash. Current AV technologies, such as Tesla’s Autopilot, are referred to by car manufacturers as “driver assistance systems” but it is not clear that all drivers understand their limitations, including the need for drivers to monitor the driving environment and stay involved in the driving process.

The Society of Automotive Engineers has developed a classification system for autonomous vehicles. The classification includes six levels (Level 0-5); with Level 5 being fully autonomous and Level 1, containing some automated features such as adaptive cruise control and parking assist. Most current automated driver assistance systems are Level 1 or 2, meaning that drivers still need to be actively involved.

Driver assistance systems and autonomous vehicles hold great promise for improving safety and mobility, but AV technologies are still relatively new, and numerous challenges remain. A number of universities and researchers in Massachusetts are exploring this topic. In April, a commentary by MIT AgeLab researchers, “People must retain control of autonomous vehicles,” was published in Nature magazine (link is for the article). In their remarks, Dr. Ashley Nune, Dr. Bryan Reimer, and Dr. Joseph Coughlin, Age Lab Director and UMass Transportation Center Research (UMTC) Affiliate, focused on two areas – safety and liability – that need urgent attention as policies and regulations are developed for autonomous and semi-autonomous vehicles. They write that, in their view, “some form of human intervention will always be required. Driverless cars should be treated much like aircraft, in which the involvement of people is required despite such systems being highly automated. Current testing of autonomous vehicles abides by this principle. Safety drivers are present, even though developers and regulators talk of full automation.” The researchers’ piece ends with key points for policymakers preparing AV legislation to consider:

  • Driverless does not, and should not, mean without a human operator
  • More information should be shared with operators/drivers about how well different autonomous and driver assist systems are working, including their reliability and limitations
  • Operators should need to demonstrate that they understand the autonomous and driver assist systems in their vehicles and should be tested on their understanding and competence at periodic intervals
  • Remote monitoring networks should be established and shift time guidelines considered for workers monitoring AVs.

In May, a forum held at Harvard University’s T.H. Chan School of Public Health on “Self-Driving Cars: Pros and Cons for the Public’s Health.” (A recording of this session and a transcript are available at this link.) Dr. Jay Winsten, Associate Dean for Health Communication at Harvard, said there is hope right now around the potential for autonomous and highly automated vehicles to reduce traffic deaths.  He also addressed the hype around this: “I think both the media and some of the manufacturers and developers have been going a little too far in setting public expectations for what to expect, especially in the short-term and in the medium-term.” The panelists discussed that initially most vehicles will be highly automated (SAE Level 2), not autonomous (Level 3-5), and the deployment of the autonomous vehicles is likely to occur first for long-distance, highway-based commercial transport and in urban areas for shuttles and other short-distance trips. There are some challenges including the current reliability and drivers’ understanding of AV technologies, including the need for drivers to stay alert while behind the wheel and the safety of vulnerable road users. There are also concerns regarding regulation. The federal government through the National Highway Safety Administration has developed some guidelines regarding autonomous vehicles and automated driving systems. However, there are currently no federal regulations in place regarding autonomous vehicles. Therefore, currently regulations are primarily set at the state level.

As described in an earlier Innovative Outlook article, Governor Baker and Massachusetts state officials have largely taken the approach that it is better not to regulate AVs through legislation, as the technologies are still evolving and legislation can be difficult to modify once passed. Panelist Deborah Hersman of the National Safety Council, shared those concerns, saying “We’ve got to find out how to do this differently” so that any regulations keep up with changing technology. Herman also urged there be more transparency and data sharing regarding specific AV technologies and how well they perform, saying that NTSB investigations after a crash can be challenged by lack of access to such data.

In June 2018, MassDOT entered into a Memorandum of Understanding with several municipalities to help facilitate and expand autonomous vehicle testing on roadways in Massachusetts. As described in a MassDOT blog article, “Following the signing of this MOU, MassDOT and the participating communities will finalize a universal application for companies to use when seeking to test autonomous vehicles and the participating municipalities will identify locations and roadways suitable for autonomous vehicle testing. ‘This agreement will allow companies to responsibly develop and test autonomous vehicle technology in Massachusetts, while ensuring there are uniform safety guidelines in place,’ said Governor Baker [at the MOU signing] . ‘The MOU builds on the existing autonomous vehicle testing framework while simplifying the process for municipalities to work with innovative companies that are seeking to advance transportation, create jobs in our nation leading innovation economy, and improve our quality of life in the Commonwealth.’  …Said Lieutenant Governor Karyn Polito, ‘By creating a standardized process and working collectively with local officials, we can generate economic growth and support our communities as they play a role in the future of innovation and motor vehicle automation.’ Fourteen communities signed the MOU initially, including Boston, Worcester, Arlington, Boston, Braintree, Brookline, Cambridge, Chelse, Medford, Melrose, Newton, Revere, Somerville, Weymouth, Winthrop, and Worcester.  In addition, the Massachusetts Department of Conservation and Recreation also joined the MOU, allowing Commonwealth-owned parkways to be available for autonomous vehicle testing.

 

 

Around and Around for Pedestrian and Cyclist Safety

by Tracy Zafian, Research Fellow, and Courtney Murtagh, UMTC Intern

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Bicycle in Roundabout (Source: bikewalkencinitas.org)

Roundabouts were introduced to America’s traffic system as a way to increase traffic safety and support greater traffic volumes without extensive new construction. A roundabout’s circular formation works by making incoming vehicles yield to circulating and exiting traffic. This allows cars to maintain a steady traffic flow through the intersection and not have to come to a complete stop. Roundabouts have been proven to be able to handle up to 50 percent more traffic compared to traditional intersections that use traffic signals or stop signs. Further, due to vehicles’ reduced speeds at roundabouts, crash and injury rates can significantly decrease, especially for motorists. According to the Insurance Institute on Highway Safety (IIHS), studies of U.S. intersections that have switched from stop signs or traffic signals to roundabouts have found a decrease in all traffic crashes of 35-47% and a reduction of injury crashes of 72-80%. The IIHS importantly notes that the U.S. studies have focused primarily on single-lane roundabouts. When included in research studies, two-lane roundabouts have been shown to have smaller reductions in crashes compared with single-lane roundabouts or even with increases in crashes. Crashes at roundabouts have also involved bicycle and pedestrians. Non-motorized road users, such as bicyclists and pedestrians, can face several safety and technical challenges when traveling through roundabouts. These challenges can lead to greater crash risk at roundabouts.  Dr. Eleni Christofa, UMTC Affiliate Researcher Civil Engineering and Professor Aura Ganz of Electric and Computer Engineering from UMass Amherst are studying the safety of visually impaired pedestrians at roundabouts. Visually impaired pedestrians may be used to having auditory cues from traffic and signals at intersections to know when it’s safe to cross. Roundabouts, designed with continuous traffic flow in mind, may not have such cues. Additionally, it can be difficult for drivers to detect pedestrians at a crosswalk while the driver is focused on navigating a roundabout.  Dr. Christofa and Dr. Ganz have developed a new dynamic warning sign to alert drivers entering a roundabout as to where pedestrians are attempting to cross. This sign contains a symbolic traffic circle and symbolic crosswalks for each approach of the roundabout. If a pedestrian is about to cross one of the roundabout’s approaches, they can activate the sign which will then flash to alert drivers where pedestrians are crossing in the roundabout. This is designed to help both with driver awareness of pedestrians and pedestrian safety. The dynamic warning sign will be tested on the UMass Amherst advanced driving simulator this summer. If the sign works as expected, it could be used to help with the safety of pedestrians at roundabouts generally and particularly for the visually impaired and those with mobility impairments who take longer in crosswalks.

 

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Proposed dynamic warning sign for pedestrian crossings at roundabouts. Pedestrians activate the sign to flash and show where they are crossing to help alert drivers traversing the roundabout to their presence.

One of Dr. Christofa’ s graduate students, Derek Roach, conducted other research on roundabouts for his Master’s thesis. His study looked at the impact of roundabouts from a driver behavior, vehicle emissions, and safety perspective. As part of his research, Roach reviewed other studies that examined the safety of bicyclists and pedestrians at roundabouts. One of these studies found that drivers who are exiting a roundabout are less likely to yield to pedestrians than when the drivers enter the roundabout.  This same study found that as speed increases in roundabouts, drivers are less likely to yield for pedestrians, making it harder and less safe for pedestrians to cross.

In terms of bicyclist safety, Roach examined a number of studies by researcher Stijn Daniels and colleagues in Belgium. Daniels’ work has found increases in the number of bicyclist crashes and in crash severity when intersections are replaced with roundabouts. Other studies have reported potential explanations for these increases. One study, by researcher Bob Cumming in Australia, found that a contributing factor of bicyclist crashes in one lane roundabouts was bicyclists staying very close to the right curb while going through the roundabout, which would lead motorists to try and pass them in the roundabout. In these cases, it is safer for bicyclists to take the main travel lane instead of being so close to the curb.

At the MassDOT’s 2017 Innovation and Tech Transfer Exchange, presenters from Kittelson and Associates gave an overview on bicycles at roundabouts, including a review of bicycle facility design standards and practices in Massachusetts and elsewhere. Each of the MassDOT Highway Districts in the state has at least one roundabout. MassDOT’s guidance for roundabouts gives special attention to rotary retrofits, building roundabouts in constrained environments, and incorporating state-of-the-practice bicycle and pedestrian design into roundabouts. One important current practice is to treat low-traffic volume and high-traffic volume roundabouts differently, to support bicyclist safety. For lower traffic roundabouts, bicycles are encouraged to circulate with motor vehicles. For higher traffic roundabouts, it is encouraged for bicycles to have a protected intersection with a separate bicycle path, and for bicyclists to have the option of either going through the intersection as a vehicle or pedestrian.

Managing Assets at MassDOT

by: Matt Mann, Research Program Coordinator

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Longfellow Bridge

MassDOT continues to monitor, repair and replace its existing transportation infrastructure.  Bridges are a key component of the infrastructure and essential for Massachusetts growing economy.  Through data collection, bridge inspections, and daily maintenance, MassDOT knows when each bridge will need to be replaced or rehabilitated.

MassDOT performs a regular and semi-regular inspection of their bridge network.   Funding for the bridge infrastructure looks at ownership and length of the structure.  Collecting bridge attributes and deficiencies allows MassDOT to develop comprehensive of their assets.

Over the past few years, the Accelerated Bridge Program (ABP) has met the challenges to reduce the number of deficient bridges in the Commonwealth.  The goal of this Program is to deliver projects quickly and relies on accelerated bridge construction as a means to reduce road closure durations. There are two specific bridge projects that are looking to accommodate demand and technology for the next generation.  One is in the implementation phase and the other in the research phase, both shining a light on MassDOT’s commitment to accommodating future transportation demand in the Commonwealth.

MassDOT is undertaking the Longfellow Bridge Rehabilitation Project, one of five major projects of the Commonwealth’s ABP. This historic bridge provides vital transportation connections between Boston and Cambridge.  Keeping in-line with the historic character of the bridge, structural deficiencies will be addressed, and multi-modal connections will be improved.

A recently launched MassDOT research project looks more closely at the deterioration of the steel beam ends due to corrosion of leaking bridge joints. Dr. Simos Gerasimidis of UMass Amherst is the Principal Investigator on the project. We asked him to give us some information on the project and the expected outcomes.

“As the Commonwealth’s bridge population ages, MassDOT is witnessing more and more instances of deterioration of the web at steel beams ends due to corrosion as a result of leaking bridge joints. This deterioration reduces the load carrying capacity of beams at a critical point where the beam sits on its bearing. In extreme cases, the web fails and the bridge has to be closed. Therefore, the determination of the remaining load carrying capacity is very important, however, there are no good methods for performing this analysis and so, it has been very difficult to calculate realistic estimates of the remaining capacity of the web. This research aims to first; identify the most common configurations (shapes and locations) of steel beam end deterioration by reviewing detailed inspection reports for various bridges. These patterns will be used to develop advanced computational models for structural analysis and the results of the analysis will be utilized to develop new procedures for determining the safe capacity of deteriorated beam ends that can be incorporated into the MassDOT Bridge Manual.

Secondly, actual steel beams with deteriorated ends will be subjected to full-scale testing at the UMass, Amherst Structural Testing Facility to validate the procedures that are being proposed. Finally, the ultimate goal of the project is to update the current guidelines as they appear in today’s codes.”

Both of these bridge projects will benefit the Commonwealth for years to come.  Combining data analysis and maintenance, with innovation and technology, will continue to keep our infrastructure in good shape.

Are Your Lights Iced?

by: Tracy Zafian, Research Fellow

Image result for train rail flashing lights

Many highway and rail signals now contain Light Emitting Diodes (LEDs). The switch to LEDs was made because of its energy efficiency. However, a one side-effect of this efficiency is that the LED lights don’t give off enough heat to melt snow or ice on their own. This can lead to the lights being obscured during winter conditions which can create potential safety hazards. In 2016, for example, there was a crash in Windsor, Ontario where a school bus entered an intersection against a red light and ran into a car. The bus driver did not see the red light-an LED, because the light was obscured by snow. Fortunately, there were no major injuries during that crash. Early this winter, the Minnesota DOT worked to clean off LED traffic signals after snow obscured signals in the Twin Cities area of the MN Highway 36, leading to at least one serious crash and many near misses.

In 2014, the Federal Highway Administration (FHWA) released a report on LED traffic signal operations in snow conditions which suggested a number of proactive and reactive measures transportation departments can take to keep LED signal lights free from ice and snow. Reactive measures, employed after a snowfall, include manually cleaning the lights or spraying them with antifreeze, deicing spray or compressed air to clean them off. Each of these measures requires personnel to visit and work on each light. Proactive measures include installing signal lens heating elements or lens covers, or spraying deicing spray on the lights before it snows. As documented in the report, such proactive measures have had various degrees of success.

Two current research studies are testing new proactive approaches, both of which involve redesigning the LEDs lights used in traffic signals. Researchers at the University of Kansas have developed and tested self-de-icing LED technology and are now working on creating a full prototype for field testing. . Their approach is to mount the LEDs in the traffic signals “backwards” to harvest the heat generated by the LEDs to heat the light lenses and keep them above freezing. With this system, no additional heating is needed to prevent ice and snow from collecting on the traffic lights. The researchers have estimated that replacing the current LED lights with new LEDs will save about $28 per signal light annually, with a payback time of 4.5 years.

A second research study is looking at developing a super hydrophobic (anti-icing) surface coating for the lenses of traffic signals. The research is being conducted at the University of Nebraska, Lincoln, and is investigating femtosecond laser surface processing (FLSP) techniques for producing thin (nanoscale) anti-wetting surfaces on hard materials, such as tungsten carbide. Testing is being conducted find the best FLSP-functionalized hard material to use as a durable stamp for imprinting an anti-icing surface on the lenses of traffic signals. This study is scheduled to be completed later this year.

MassDOT at TRB 2018!

by: Matt Mann, Research Program Coordinator

Image result for transportation infrastructure repurposing

Nikki Tishler, Transportation Planner and Title VI Strategist for MassDOT, provided great moderating skills at last week’s Transportation Research Board Annual Conference, as she orchestrated the session: Repurposing and Resizing Our Infrastructure: Responsible Investment for the New World.  The presentations and discussions centered on right-sizing the infrastructure for future transportation function, efficiency and service.  DOT’s continue to improve project and asset management processes as they integrate existing and future societal needs with an anticipated reduction in funding.

New Federal Committee on Motorcycle Safety Holds First Meeting

by Tracy Zafian, Research Fellow

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Last month, the Motorcycle Advisory Committee (MAC) held its initial meeting in Arlington, VA. This federal committee was created to advise the Federal Highway Administration (FHWA) on motorcycle safety and to identify engineering-related infrastructure solutions for reducing motorcyclist fatalities.

There were 5,286 roadway fatalities nationally involving motorcycles in 2016, an increase of 5% from the previous year. In Massachusetts, 40 motorcyclist fatalities were reported during the same year.

As described on transportation.gov, “the MAC consists of ten members selected by the U.S. Secretary of Transportation Elaine L. Chao. [The members] come from across the country and are experts in a wide range of motorcycle-infrastructure topics. Each is a motorcyclist and, combined, the MAC members have over two centuries of riding experience.”

At the first MAC meeting, there were substantial discussions on many infrastructure issues, including work zones, roundabouts, roadside hardware, roadway maintenance practices, the potential consequences of automated vehicles and crash testing, among others. At upcoming meetings, the MAC will determine how to advise FHWA on these issues. For its part, FHWA has research underway to identify key infrastructure-based safety issues for motorcyclists. The centerpiece of this work is the FHWA’s Motorcycle Crash Causation Study. According to the study web site, “The Motorcycle Crash Causation Study is the most comprehensive data collection effort to study the causes of U.S. motorcycle crashes in more than 30 years. The dataset includes data from at least 351 crash investigations, and 702 control rider interviews.”

A couple of current safety features on motorcycles to prevent future fatalities include: new breaking lights and the required anti-lock brake feature. The break light feature is the first wearable brake light connected to a smart phone app.  The anti-lock brake feature has been an option on motorcycles for years, but it may soon become a requirement based on the safety advantages.

In addition to technology and infrastructure improvements for motorcycle safety, some changes in how motorcyclists are trained may be warranted as well. Researchers at UMass-Amherst, led by now Ph.D. graduate Jeffrey Muttart, have conducted field studies on motorcyclist eye glance and driving behavior, including studies where participants went through the same on-road course as car drivers and as motorcyclists. Key findings in one study were that motorcyclists were less likely to come to a complete stop at a stop sign than car drivers, and that study participants made later final glances toward the direction of the most threatening traffic before they made a turn when they were driving a car than when they were riding a motorcycle.

Traffic Apps Impact on Neighborhoods and Safety

by Tracy Zafian, Research Fellow

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Photo by Noe Veloso Fremont, CA Public Works Department

Smart phone apps, such as Waze and Google Maps, help drivers find the quickest routes to their destinations using real-time traffic data.  Sometimes this means that drivers are being directed off congested highways to streets through residential neighborhoods instead. Not everyone is happy about this, including traffic planners and people living in these neighborhoods who don’t want higher volumes of traffic on their streets.

News media have reported these impacts of traffic apps on Cape Cod neighborhoods, and in the Boston area.  Quoting Police Sergeant Charles Hartnett, head of Medford’s traffic division, in one news report: “For the residents, it’s a safety issue.”  Some communities are responding by restricting a cut-through and turning movements into residential neighborhoods during commuting hours when the traffic is heaviest.  In some places, certain streets are being changed to one-way roads as another means to divert traffic.  When such changes are made, transportation planners often share these updates with the app companies so that their maps and algorithms can be adjusted accordingly.

The traffic apps can also present a challenge to safety officials in emergency situations.  For example, in the Los Angeles area, while officials were busy fighting wildfires, they implored residents to ignore the apps that were directing them to lightly traveled roads in the fire zones, and put up message signs telling drivers “Don’t Trust Your Apps.” As described in this USA Today article, the fires and evacuation orders were the reason the traffic volumes is these areas were so low.  In Vermont, the shortest way isn’t always the safest way.  Cars have been abandoned because the driver followed Google maps, only to end up on a road that was not maintained in the winter.