January 2022: New Publication-Literature Review on Wheelchair Transportation Safety
Happy to announce that our new open access journal article Literature Review on Wheelchair Transportation Safety is now available. Given the renewed interest in providing independent transportation solutions for wheelchair users in future automated vehicles, we thought it would be useful to compile previous research where it would be available to everyone.
January 2022: SAE Government/Industry Meeting
We were able to present the Part II of our work to Develop an Automated Wheelchair Tiedown and Occupant Restraint System at this year’s SAE Government/Industry Meeting. Disappointed that I couldn’t attend in person, but was happy to have the opportunity to chat with fellow TRC alums David Zuby and Aloke Prasad before our session.
January 2022: Inclusive Design Challenge Virtual Workshop
We were able to present progress on our Inclusive Design Challenge project with our partners from May Mobility on January 24. You can view see our presentation on Independent Safety for Wheelchair Users in AVs, as well as the other nine participants. We are excited to be starting evaluations with volunteers over the next few months.
August 2021: Wheelchair Transportation Safety Open House
We were excited to share our latest research on wheelchair transportation safety at our Virtual Wheelchair Transportation Safety Open House. That link will let you download a pdf of our presentation, as well as a copy of the final report once it is approved for release.
October 2021: US Occupancy Trends
At this years virtual AAAM conference, we were able to share our study U.S. Vehicle Occupancy Trends Relevant to Future Automated Vehicles and Mobility Services. The work was also published in Traffic Injury Prevention.
March 2021: US Access Board Public Dialogue on Accessible AVs
My colleague, Miriam Manary, and I were honored to be panelists at one of four workshops hosted by the US Access Board to foster public dialogue about accessible autonomous vehicles. We were able to share our initial progress on our work funded by NHTSA to develop automated wheelchair tiedowns and occupant restraint systems. You can view a a recording of the workship that includes our presentation titled Development of an Automated Wheelchair Tiedown and Occupant Restraint System: Initial Progress.
February 2021: SAE Government/Industry Meeting
It wasn’t the same as heading to DC, but we were happy to present initial progress on our NHTSA project to develop an automated wheelchair tiedown and restraint system at SAE’s government/industry meeting. You can see our virtual presentation Development of an Automated Wheelchair Tiedown and Occupant Restraint System: Initial Progress.
September 2020: CPS Conferences
Child passenger safety technicians (CPSTs) need to earn continuing education units to stay certified, so many states organize CPS conferences each year. I was able to speak at two conferences remotely this month. For Georgia, I shared “Effects of Child Restraint Misuse and Factors Affecting Child Injury Risk”, while for Ohio, I presented “Building a Better Booster: New Volunteer Evaluations and Dynamic Metrics”. Thanks for the invitiations-hope to meet you in person at a future conference!
June 2020: National Safety Council Webinar
We appreciate the effort made by different organizations to continue to share our research while we stay at home. I was able to share results of our National Safety Council project “Socioeconomic Status Factors in Motor Vehicle Fatality Mitigation Efforts” at a webinar on June 30. While we miss presenting at their annual meeting, it was a great opportunity to expand our audience. The webinar is archived at nsc.org if you join (for free!)
April 2020: NHTSA Shares UMTRI Research Reports
We were happy to learn that NHTSA released several of our reports relating to dynamic testing and performance of child restraint systems:
- Investigation of potential design and performance criteria for booster seats through volunteer and dynamic testing
- Development of a Surrogate Shoulder Belt Retractor for Sled Testing of Booster Seats
- Comparing the CRABI-12 And CRABI-18 for Infant Child Restraint System Evaluation
March 2020: New Mexico Child Passenger Safety Conference
I was happy to visit Albuquerque, New Mexico to present at the New Mexico Child Passenger Safety Conference. The organizers were impressive and the venue was lovely. I was able to share a presentation titled “Misuse and Best Practice: What does the Latest Research Show?”, highlighting our dynamic study to evaluate the effects of misuse, and the analysis of NASS-GES data to identify factors related to pediatric injury in crashes.
January 2020: New Paper on Child Volunteers in Boosters Published
We have published results of our latest study with child volunteers in the International Journal of Environmental Research and Public Health, “Child Posture and Belt Fit in a Range of Booster Configurations.”
The objective of this research was to quantify differences in posture and belt fit across a range of booster designs that provide different levels of boosting. Posture and belt fit were measured in 25 child volunteers aged four to 12. Children were measured in three laboratory seating conditions selected to provide a range of cushion lengths and belt geometries. Six different boosters, as well as a no-booster condition, were evaluated. The low height boosters produced postures that were more slouched, with the hips further forward than in other more typical boosters. Lap belt fit in the low height boosters was not meaningfully different from the other boosters. Shoulder belt fit produced by the lowest height booster was similar to the no-booster condition. Belt positioning boosters that boost the child less than 70 mm produced postures similar to the no-booster condition. While lap belt guides on these products can produce a similar static lap belt fit, they may not provide adequate dynamic performance and do not achieve the other benefits that come with raising the child to a more advantageous location relative to interior components and belts.
Novermber 2019: Pediatric Motor-Vehicle Injury Risk Paper Presented at Stapp Conference
Over the past few years, Dr. Carol Flannagan and I have been honored to mentor Dr. Marco Benedetti, a recent graduate from the UM Biostatistics department. This November, he was able to present our work to examine the factors associated with pediatric injury in motor-vehicle crashes at the Stapp Conference in San Antonio, Texas. Here’s the abstract:
Current recommendations for restraining child occupants are based on biomechanical testing and data from national and international field studies primarily conducted prior to 2011. We hypothesized that analysis to identify factors associated with pediatric injury in motor-vehicle crashes using a national database of more recent police-reported crashes in the United States involving children under age 13 where type of child restraint system (CRS) is recorded would support previous recommendations. Weighted data were extracted from the National Automotive Sampling System General Estimates System (NASS-GES) for crash years 2010 to 2015. Injury outcomes were grouped as CO (possible and no injury) or KAB (killed, incapacitating injury, nonincapacitating injury). Restraint was characterized as optimal, suboptimal, or unrestrained based on current best practice recommendations. Analysis used survey methods to identify factors associated with injury. Factors with significant effect on pediatric injury risk include restraint type, child age, driver injury, driver alcohol use, seating position, and crash direction. Compared to children using optimal restraint, unrestrained children have 4.9 (13-year-old) to 5.6 (< 1-year-old) times higher odds of injury, while suboptimally restrained children have 1.1 (13-year-old) to 1.9 (< 1-year-old) times higher odds of injury. As indicated by the differences in odds ratios, effects of restraint type attenuate with age. Results support current best practice recommendations to use each stage of child restraint (rear-facing CRS, forward-facing harnessed CRS, belt-positioning booster seat, lap and shoulder belt) as long as possible before switching to the next step.
October 2019: Child Restraint Misuse Paper Published
Our paper describing research to evaluate “Effects of child restraint misuse on dynamic performance” has been published in Traffic Injury Prevention. Here’s the abstract:
Estimates of child restraint misuse rates in the United States range from 49% to 95%, but not all misuse modes have similar consequences in terms of restraint effectiveness. A series of laboratory sled tests was conducted to determine the effects of common misuses and combinations of misuses, including loose harness, loose installation, incorrect installation angle, incorrect belt path, loose/no tether, and incorrect harness clip usage. Three commercial convertible child restraint models were loaded with the Hybrid III 3-year-old anthropomorphic test device (ATD) and secured by either LATCH or seat belt on a modified FMVSS No. 213 bench. Tests were conducted in forward-facing (FF) and rear-facing (RF) modes. The response variables included ATD accelerations, excursions, and restraint kinematics. Belt/LATCH loads, tether loads, ATD kinematics, and restraint structural response data were also documented. A fractional factorial test design on 8 factors was used to define an initial series of 32 tests. The first series also included 4 tests of correct CRS, 2 forward facing and 2 rearward facing. The analysis of those data determined the selection of conditions for the remaining 20 tests to focus on factors and interactions of high interest and significance. In the RF condition, misrouting the LATCH belt or seat belt through the incorrect belt path was the only misuse that significantly affected outcomes of interest and was associated with high levels of undesirable CRS rotation. In FF tests, loose installation and tether misuse had large adverse effects on 3 of 4 key response variables. The study provides strong evidence for prioritizing tight restraint installation and proper tether use for FF restraints. In particular, use of the tether helped offset the adverse effects of loose installation or loose harness. Because the results show that performance of a RF child restraint system (CRS) installation is less affected by user error, they also provide support for extended RF restraint use. In addition, packaging convertible child restraints with the LATCH belt routed through the RF belt path could help prevent the most consequential RF CRS misuse.
April 2019: Seatbelt Entanglement at SAE Congress
I was able to share work at this year’s SAE congress regarding our project to assess devices to prevent seatbelt entanglement. I was joined by co-authors Bill Lipetlo and Jason Sidman from tool, inc. Since 2000, over 200 rear seat occupants have become entangled in the seatbelt when they inadvertently switched it from emergency locking mode (ELR) to automatic locking mode (ALR). Since a method is needed to lock the seatbelt when installing child restraint systems (CRS), the National Highway Traffic Safety Administration (NHTSA) commissioned tool, inc. to develop prototype devices that could reduce the risk of seatbelt entanglement resulting from the lockability requirement. A field analysis of entanglement incidents was first conducted to inform countermeasure design. Prototype devices were developed and evaluated through testing with volunteer subjects in comparison to standard seatbelt systems by assessing how different designs would be used to install CRS, the quality of the resulting installations, how users would disentangle a trapped child surrogate, as well as to identify volunteer experience when using the belts themselves. Four prototype devices were evaluated in two phases of testing conducted at the UMTRI. All four prototype devices had shorter disentanglement times than trials with the standard seatbelt, but there was not a statistically significant difference between the devices. There were no substantial differences in the quality of child restraint installation among the devices and the standard seatbelt.
Here’s a link to our presentation.
April 2019: New Articles on CPS Resources Available
Two papers on assessing child passenger safety resources are now available. Thanks to our co-author, Michelle Macy, for shepherding these through the publication process.
February 2019: New Paper on Child Models
Our paper describing development of three-dimensional child models that can be used for child restraint design is now available.
September 2018: NHTSA Releases UMTRI CPS Reports
We have learned that NHTSA has released several past reports describing UMTRI work related to child passenger safety. Here are links:
- Assessment of ATD Selection and Use for Dynamic Testing of Rear-facing Child Restraint Systems for Larger Infants and Toddlers
- Development of Fit Envelopes to Promote Compatibility Among Vehicles and Child Restraints
- Effect of tether routing and anchor location on child restraint kinematics
- Toddler Lower-Extremity Posture in Child Restraint Systems
June 2018: Road to Zero Presentation
I was pleased to join the speakers at the June 28, 2018 Road to Zero Coalition meeting in Washington, DC. We had received funding from the National Safety Council to upgrade our UTMOST tool to allow visualization of fatalities and how different technologies could help address the problem. A link to my presentation can be found here.
April 2018: MEDC Intern Poster Reception
UMTRI hosted a poster reception on April 18, 2018 to highlight the work performed by its inaugural class of Michigan Economic Development Corporation (MEDC) transportation interns; I am serving as coordinator of the program. The MEDC provided funding for ten interns in Winter 2018 and another 19 for the Spring/Summer term. The goal of the internships is to provide junior and senior students with skills and knowledge relevant to emerging careers in transportation. Research topics addressed included automated vehicles, human modeling, and mapping tools for connected vehicles.
February 2018: New Paper Comparing Crash Risk in EU and US
Our paper on “Comparing motor-vehicle crash risk of EU and US vehicles” was published in Accident Analysis and Prevention this month. This project was a wonderful opportunity to collaborate with other safety researchers in Europe.
January 2018: SAE Government/ Industry
This month I was able to attend the SAE Government/Industry meeting held January 24-26. Everyone was relieved that the shutdown was resolved in time for the government employees to attend so it wasn’t just a /Industry meeting. I presented a project we did for NHTSA to “Develop a Surrogate Seatbelt Retractor for Use in Child Restraint Testing”. We received permission to share the report on the project; you can download from here.
My colleague Daniel Park also attended and presented “Toward Integrated Safety: Occupant Dynamics in Crash Avoidance Maneuvers.”
December 2017: New MEDC Intern Program
We’re excited to announce a new opportunity for undergraduate students to have a practical research experience in the field of transportation. The UMTRI/MEDC (Michigan Economic Development Corporation) Internships were launched this month, and I am serving as the faculty coordinator. We will have 12 interns in the Winter 2018 term and 19 for the Spring/Summer. We have modeled the application process after the UM UROP program, where UMTRI researchers post projects, and students apply to those of interest. You can find out more information about the program here on the UMTRI website.
November 2017: Stapp Conference
This month I attended the 61st Stapp Car Crash Conference in Charleston, SC. A highlight was seeing my colleague Jingwen Hu present “Optimizing Seat Belt and Airbag Designs for Rear Seat Occupant Protection in Frontal Crashes”. This NHTSA-funded study is the most comprehensive study in the literature for rear-seat restraint designs in frontal crashes. It highlights the potential benefit of using advanced seatbelt (e.g. pre-tensioner and load limiter) and airbag systems for rear-seat occupants.
October 2017: Tether Use in Pickups
Our study for the Insurance Institute for Highway Safety on tether use and usability in pickup trucks is now available at Traffic Injury Prevention. Our goal was to Investigate vehicle factors associated with child restraint tether use and misuse in pickup trucks and evaluate four labeling interventions designed to educate consumers on proper tether use. We performed volunteer testing with 24 subjects and four different pickup trucks. Each subject performed eight child restraint installations among the four pickups using two forward-facing restraints. We chose vehicles to represent four different implementations of tether anchors among pickups. Interventions included a diagram label, QR Code linked to video instruction, coordinating text label, and contrasting text tag.
Subjects used the child restraint tether in 93 percent of trials. However, tether use was completely correct in only 9 percent of trials. An installation was considered functional if the subject attached the tether to a tether anchor and had a tight installation (ignoring routing and head restraint position); 28 percent of subjects achieved a functional installation. The most common installation error was attaching the tether hook to the anchor/router directly behind the child restraint (near the top of the seatback) rather than placing the tether through the router and attaching it to the anchor in the adjacent seating position. The Nissan Frontier, with the anchor located on the back wall of the cab, had the highest rate of correct installations but also had the highest rate of attaching the tether to components other than the tether anchor (seat adjustor, child restraint storage hook, around head restraint). None of the labeling interventions had a significant effect on correct installation; not a single subject scanned the QR Code to access the video instruction.
February 2017:UTMOST Upgrades
We are pleased to announce an upgrade to the UTMOST tool. The UTMOST (Unified Theory for Mapping Opportunities for Safety Technology) tool is designed to allow visualization of the benefits of multiple safety countermeasures and to understand how combinations of those countermeasures might influence the crash population. With funding from the Toyota Class Action Settlement Safety Research and Education Program, this major upgrade of the UTMOST model included several new modules to estimate the safety benefits of several crash avoidance features, as well as effects of state laws on child restraint systems and teen graduated licensing.