Miriam A Manary

• M.S.E. Bioengineering
• Senior Engineering Research Associate at University of Michigan

Objective: The objective of this study was to develop and validate finite element (FE) models of commercial manual and power wheelchairs, as well as related test fixtures and tiedown hardware, to provide tools for designing integrated wheelchair seating stations for automated and other vehicles. Methods: The manual wheelchair model is based on a...

Objective: The advent of automated vehicles (AVs) provides an opportunity to design integrated wheelchair seating stations that provide an equivalent level of safety for occupants using wheelchairs as those using vehicle seating. This study designed a frontal occupant protection system for an integrated second-row wheelchair seating station that i...

The objective of this study was to use computational models to study how unconventional seating positions and orientations in vehicles with Automated Driving System (ADS) may affect occupant response metrics of children with various restraint conditions. A literature review was first conducted to frame a simulation plan, including selections of sur...

Objective: Previous research on occupant protection systems for wheelchair-seated occupants focused on frontal impacts, while similar studies on side impacts are very limited. The objective of this study was to identify the major injury concerns for wheelchair-seated occupants in side impacts and develop restraint systems to mitigate such injury co...

This literature review summarizes wheelchair transportation safety, focusing on areas pertinent to designing automated vehicles (AVs) so they can accommodate people who remain seated in their wheelchairs for travel. In these situations, it is necessary to secure the wheelchair to the vehicle and provide occupant protection with a Wheelchair Tiedown...

Objective The purpose of this research was to explore candidate booster performance metrics that may have the potential to identify less effective booster systems, because current FMVSS No. 213 booster performance requirements can be met without a booster. Methods To provide a more realistic test environment, dynamic testing was performed using a...

Objective: Field data have shown significant benefit from driver airbag for occupant protection in frontal crashes. However, vehicle modifiers almost always permanently deactivate airbags for wheelchair-seated drivers. The objective of this study was to conduct sled tests and computational simulations to answer whether driver airbags should be deac...

Belt positioning boosters reduce injury risk for child occupants compared with seat belts alone. While boosters shorten the effective seat length (and thus reduce slouching), “boosting” the child relative to the vehicle interior components also achieves additional safety benefits. First, the increase of the lap belt angle usually improves belt fit...

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 cras...

Objective: 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,...

Objective: The purpose of this article was to assess the match between child passenger safety resources (child passenger safety technicians [CPSTs], car seat checks, and child restraint system [CRS] distribution programs) and the child population in Michigan by utilizing geographic information systems approaches and to analyze the impact of Michiga...

Objective: In this study, we assessed the number of child passenger safety technicians (CPSTs) in Michigan over 4 years and characterized the CPST workforce in 2015 to identify factors associated with high productivity and longevity in the field. Methods: We determined the number of CPSTs and those newly certified using lists from the Michigan Offi...

Objective: This study examined the hypotheses that passenger vehicles meeting European Union (EU) safety standards have similar crashworthiness to United States (US) -regulated vehicles in the US driving environment, and vice versa. Methods: The first step involved identifying appropriate databases of US and EU crashes that include in-depth cras...

Objective: 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. Methods: Volunteer testing was performed with 24 subjects and four different pickup trucks. Each subject performed eight child restraint installati...

Objectives. Identify factors that predict restraint use and optimal restraint use among children aged 0 to 13 years. Methods. The dataset is a national sample of police-reported crashes for years 2010-2014 in which type of child restraint is recorded. The dataset was supplemented with demographic census data linked by driver zip code, as well as a...

Objective: Federal regulations in the United States require vehicles to meet occupant performance requirements with unbelted test dummies. Removing the test requirements with unbelted occupants might encourage the deployment of seatbelt interlocks and allow restraint optimization to focus on belted occupants. The objective of this study is to comp...

Background: State laws regarding child passenger protection vary substantially. Objectives: Develop a scoring system to rate child passenger safety laws relative to best practice recommendations for each age of child. Methods: State child passenger safety and seatbelt laws were retrieved from the Lexis-Nexis database for the years 2002–2015. Text o...

Pediatric occupants of motor vehicles need the specialized protection provided by child restraint systems because of their immature and developing body structures. The best child restraint system for a child depends on the size, age, and development level. As children proceed through the four phases of restraints systems (rear-facing harnessed rest...

This study examined the hypotheses that vehicles meeting EU safety standards perform similarly to US-­‐regulated vehicles in the US driving environment, and vice versa. The analyses used three statistical approaches to “triangulate” evidence regarding differences in crash and injury risk. Separate analyses assessed crash avoidance technologies, inc...

Objectives: The objectives of this study are to use computer simulation to evaluate the International Organization for Standardization (ISO) 13216-3:2006(E) child restraint system (CRS) envelopes relative to rear seat compartments from vehicles and CRSs in the U.S. market, investigate the potential compatibility issues of U.S. vehicles and CRSs, a...

Introduction Field studies show that top tethers go unused in half of forward-facing child restraint installations. Method In this study, parent volunteers were asked to use the Lower Anchors and Tethers for Children (LATCH) to install child restraints in several vehicles to identify tether anchor characteristics that are associated with tether us...

Ninety-eight 2010–2011 model year vehicles were surveyed to evaluate the usability of hardware known as Lower Anchors and Tethers for Children, or LATCH, required by US FMVSS 225. Most vehicles do not provide LATCH hardware beyond the minimum number of required seating positions. Only seven vehicles had three sets of LATCH hardware in the second ro...

Phase 1 of the Mutual Recognition Methodology Development (MRMD) project developed an approach to statistical modeling and analysis of field data to address the state of evidence relevant to mutual recognition of automotive safety regulations. Specifically, the report describes a methodology that can be used to measure evidence for the hypothesis t...

Objective: Lower anchors and tethers for children (LATCH) was intended to standardize the attachment between child restraints and vehicle seats. However, LATCH implementations vary, resulting in differences in ease of attachment of child restraint connectors. Identifying vehicle characteristics associated with correct child restraint installations...

This project assessed current or proposed protocols for improving the usability of LATCH (Lower Anchors and Tethers for Children). LATCH hardware in the left second-row position of 98 2011 or 2010 model-year vehicles was evaluated using ISO and SAE LATCH usability rating guidelines. Child restraint/vehicle interaction was assessed using ISO and NHT...

This study examined how child restraint system (CRS) features contribute to CRS installation errors. Sixteen convertible CRS, selected to include a wide range of features, were used in volunteer testing with 32 subjects. Subjects were recruited based on their education level (high or low) and experience with installing CRS (none or experienced). Ea...

A laboratory study was conducted to quantify the effects of belt-positioning boosters on lap and shoulder belt fit. Postures and belt fit were measured for forty-four boys and girls ages 5-12 in four highback boosters, one backless booster, and on a vehicle seat without a booster. Belt anchorage locations were varied over a wide range. Seat cushion...

This position paper is based on the premise that those who ride seated in wheelchairs are entitled to equivalent occupant safety when they are traveling in motor vehicles. The document summarizes research and best practice for safety and selection of crashworthy wheelchairs with the requisite features required by the WC19 safety standard when it is...

Occupant restraint systems are designed based on knowledge of crash dynamics and the application of proven occupant-protection principles. For ambulatory children or children who use wheelchairs but can transfer out of their wheelchair when traveling in motor vehicles, there is a range of child safety seats that comply with federal safety standards...

Questions are often raised about whether the use of postural support devices while seated in a wheelchair during travel in a motor vehicle can have potential benefits or result in harm. The benefits or harm are generally unknown as current crash-test dummies are not designed to evaluate postural supports, and there are little to no injury data for...

Commercial automotive child restraint systems (CRSs) do not accommodate all children with special healthcare needs. This study developed an alternative harness for a commercial CRS to meet the needs of children for whom a five-point harness cannot be positioned over medically involved areas and/or children whose conditions require the harness belts...

Design and test a new pelvis for the Hybrid III 6-year-old (6YO) anthropometric test device (ATD) with a more humanlike bone structure, flesh contour, and flesh stiffness intended to provide more realistic interaction with belt restraints. Target geometry for the new pelvis bone was based on a 3D model of the skeletal pelvis derived from statistica...

Three different models of forward-facing CRS were evaluated dynamically using a two-point belt fixation (FMVSS 213 Standard). Ann additional test was conducted with one same model of CRS but using the three-point belt fixation. Results showed that CRS performance differ strongly according to belt fixation being the two-point belt securement dangero...

The Rehabilitation Engineering Research Center on Wheelchair Transportation Safety held a state-of-the-science workshop on wheelchair transportation. The workshop had three purposes: reviewing and documenting the status of wheelchair transportation safety, identifying deficiencies, and formulating, discussing, and prioritizing recommendations for f...

ANSI/RESNA WC19 (i.e., WC19) is a voluntary standard that specifies design and performance requirements for wheelchairs that are suitable for use as seats in motor vehicles. The guiding principles for the standard originate from automotive crash-protection principles that are effective in reducing occupant injuries and fatalities. In addition to fr...

Belt-positioning booster seats are recommended for children who use vehicle seat belts as primary restraints but who are too small to obtain good belt fit. Previous research has shown that belt-positioning boosters reduce injury risk, but the belt fit produced by the wide range of boosters in the US market has not previously been assessed. The pres...

The pelves of the child dummies of the widely used Hybrid-III family are based on minimal data from children. Because an accurate pelvis design is critical for realistic assessments of belt restraint interactions, an analysis of medical imaging data was conducted to develop guidance for improved pelvis design. Three-dimensional polygonal meshes of...

Practitioners' responsibility for students who use wheelchairs extends to ensuring that the students travel to and from school as safely as possible.

A survey among 127 wheelchair users was conducted to characterize wheelchair occupant restraint usage patterns, restraint deficiencies, user characteristics, and essential wheelchair occupant restraint design parameters for when individuals travel in motor vehicles while seated in their wheelchairs. Survey respondents value independent travel and s...

Safe transportation for wheelchair users who do not transfer to the vehicle seat when traveling in motor vehicles requires after-market wheelchair tiedown and occupant restraint systems (WTORS) to secure the wheelchair and provide crashworthy restraint for the wheelchair-seated occupant. In the absence of adequate government safety standards, volun...

Riding on a school bus is one of the safest forms of transportation in the U.S. Every year 450,000 public school buses travel more than 4.3 billion miles to transport 23.5 million children to and from school and school related activities. Students are reportedly eight times safer on the school bus than they are in cars. However, the percentage of t...

Children and adults who must remain seated in their wheelchairs while traveling are often at a disadvantage in terms of crash safety. The new voluntary wheelchair industry standard WC19 (short for Section 19 of the ANSI/RESNA wheelchair standards) works to close the safety gap by providing design and performance criteria and test methods to assess...

The outcomes of crash tests can be influenced by the initial posture and position of the anthropomorphic test devices (ATDs) used to represent human occupants. In previous work, positioning procedures for ATDs representing adult drivers and rear-seat passengers have been developed through analysis of posture data from human volunteers. The present...

A series of sled tests was performed to analyze the responses of an anthropomorphic test device (ATD), particularly neck forces, when rear-facing child restraint systems (CRS) are tethered. Nominally identical rear-facing CRS were tested in four tether conditions: untethered, tethered down to the floor, tethered down to the bottom of the vehicle se...

This paper presents a laboratory study of body dimensions, seated posture, and seatbelt fit for children weighing from 40 to 100 lb (18 to 45 kg). Sixty-two boys and girls were measured in three vehicle seats with and without each of three belt-positioning boosters. In addition to standard anthropometric measurements, three-dimensional body landmar...

A new model for predicting automobile driving posture is presented. The model, based on data from a study of 68 men and women in 18 vehicle package and seat conditions, is designed for use in posturing the human figure models that are increasingly used for vehicle interior design. The model uses a series of independent regression models, coupled wi...

Wheelchairs are not typically designed to function as motor vehicle seats. However, many wheelchair users are unable to transfer to a vehicle seat and instead travel seated in their wheelchair. ANSI/RESNA WC19: Wheelchairs Used as Seats in Motor Vehicles provides design and testing requirements, but does not provide wheelchair manufacturers with de...

Research over the past decade has led to the development of a new, integrated suite of tools for vehicle interior design. These tools are based on posture and position data collected from hundreds of drivers and passengers in dozens of vehicles driven on-road, as well as data from laboratory studies with reconfigurable vehicle mockups. The tools in...

The objectives of the study were to determine the most effective and reliable means of restraining children on an ambulance cot and to develop recommended field procedures for emergency medical service providers. A series of crash tests at 48 km/h were conducted using convertible child restraints, car beds, and harness systems tested with 3-year, i...

The effects of vehicle package, seat, and anthropometric variables on posture were studied in a laboratory vehicle mockup. Participants (68 men and women) selected their preferred driving postures in 18 combinations of seat height, fore-aft steering wheel position, and seat cushion angle. Two seats differing in stiffness and seat back contour were...

Recent research in the ASPECT (Automotive Seat and Package Evaluation and Comparison Tools) program has led to the development of a new method for automobile driver posture prediction, known as the Cascade Model. The Cascade Model uses a sequential series of regression functions and inverse kinematics to predict automobile occupant posture. This pa...

A simulator study of the effects of the height of the top of the instrument panel (IP) on driving posture was conducted. Eight midsize men and 8 small women drove an interactive simulator with a large-screen display under 5 different IP-height conditions. The 3-dimensional locations of body landmarks were recorded to characterize their driving post...

In this paper a new approach to driver seat position modeling is presented. The equations of the Seating Accommodation Model (SAM) separately predict parameters of the distributions of male and female fore/aft seat position in a given vehicle. These distributions are used together to predict specific percentiles of the combined male and female seat...

Society of Automotive Engineers (SAE) Recommended Practice J941 describes the eyellipse, a statistical representation of driver eye locations. Eye position data collected recently at University of Michigan Transportation Research Institute (UMTRI) suggest that the SAE J941 practice could be improved. SAE J941 currently uses the SgRP (vehicle seatin...

Data from 259 frontal impact sled tests of commercial wheelchairs and seating systems were compiled and retrospectively analyzed. These data have general application to the development of additional design and performance requirements for transit wheelchair (WC) standards, and are specifically needed to guide the design and performance specificatio...

A series of sled tests was performed using the Q3S anthropomorphic test device (ATD) and the ECE R44 sled buck to study CRS and pediatric occupant kinematics in far-side impacts. Using one model of convertible child restraint system (CRS), tests were performed using a 24 km/hr, 20 g pulse to compare ATD and CRS response to lateral loading in both f...

Eighteen wheelchair-seated drivers were observed while moving into position to drive their personal vehicle. The ease-of-use and positioning of the belt restraint system by the wheelchair-seated driver were evaluated and compared for two different configurations of the wheelchair armrests: closed-front and open-front. Closed-front wheelchair armres...

Achieving proper fit of the shoulder-­‐belt for the wide range of students who remain in their wheelchairs during transport in school buses requires adjustability of the loca<on of the upper shoulder-­‐belt anchor point. In this study, op<mal upper shoulder-­‐belt anchor point loca<ons from 342 wheelchair frontal-­‐ impact sled tests conducted in a...

The distance between the driver and the steering-wheel airbag module at the time of deployment has been identified as an important factor affecting the frequency and severity of airbag-induced injuries. Pre-crash positioning may influence the clearance at the time of deployment. Data from in-vehicle studies of driving posture were analyzed to deter...

A total of 49 dynamic sled tests were performed with the Hybrid III 10YO to examine issues relating to child belt fit. The goals of these tests were to evaluate ATD response to realistic belt geometries and belt fit, develop methods for accurate, repeatable evaluation of restraint conditions for older children, identify dependent measures that diff...