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Wheels in motion: Improving mobility technologies for children

February 28, 2024

Being able to easily get from the house to the playground affects how long and how often children use an adapted ride-on car, according to a study, Off to the park: a geospatial investigation of adapted ride-on car usage, published by CREATE Ph.D. student Mia Hoffman with CREATE associate directors Heather A. Feldner (lead researcher on the project), Katherine M. Steele, and Jon Froehlich. Their research demonstrates the importance of accessibility in the built environment and that advocating for environmental accessibility should include both the indoors and outdoors.

Two children ride in small toy cars, one of which has an adapted steering wheel to make it accessible for the child to use.

For a recent study, adapted ride-on cars were provided to 14 families with young children in locations across Western Washington. Photo courtesy of Heather Feldner.

Ride-on cars are miniature toy cars for children with steering wheels and a battery-powered pedal. Adapted ride-on cars are an easy-to-use temporary solution for children with mobility issues. Although wheelchairs have more finite control, insurance typically covers new wheelchairs every five years. Children under age 5 can use adapted ride-on cars to explore their surroundings if they outgrow their wheelchair, or if they aren’t able to be in a wheelchair yet.

Exploration is critical to language, social and physical development. There are big benefits when a child starts moving.

Mia Hoffman, CREATE Ph.D. student

“Adapted ride-on cars allow children to explore by themselves,” says Mia Hoffman, the Ph.D. candidate in mechanical engineering who co-authored the paper published in fall 2023. “Exploration is critical to language, social and physical development. There are big benefits when a child starts moving.”

The researchers adapted the ride-on cars to make them more accessible. Instead of a foot pedal, children might start the car with a different option that’s accessible to them, such as a large button or a sip-and-puff, which is a pneumatic device that would respond to air being blown into it. Researchers added additional structural supports to the device, such as a backrest made out of kickboards or PVC side-supports.

Adapted ride-on cars were provided to 14 families with young children in locations across Western Washington. Heather Feldner, an assistant professor in the Department of Rehabilitation Medicine and adjunct assistant professor in ME, trained families on how to use the cars. The families then spent a year playing with the cars. Each car had an integrated data logger that tracked how often the child pressed the switch to move the car, and GPS data indicated how far they traveled.

The study found that most play sessions occurred indoors, underscoring the importance of indoor accessibility for children’s mobility technology. However, children used the car longer outdoors, and identifying an accessible route increased the frequency and duration of outside play sessions. Study participants drove outdoors more often in pedestrian-friendly neighborhoods, measured by researchers with the Walk Score, and when close to accessible paths, measured by Project Sidewalk’s AccessScore.

“Families can sometimes be uncertain about introducing powered mobility for their children in these early stages of development,” says Feldner. “But ride-on cars and other small devices designed for kids open up so many opportunities — from experiencing the joy of mobility, learning more about the world around them, enjoying social time with family and friends in new environments, and working on developmental skills. We want to work with kids and families to show them what is possible with these devices, listen to their needs and ideas, and continue working to ensure that both our technology designs and our community environments are accessible and available for all.”

Exploring different mobility devices

Heather Feldner and Mia Hoffman stand next to their poster board about adapted ride-on cars research at a conference.

As a graduate student, Hoffman conducts research on children ages 3 and under who might crawl, roll, sit up, or cruise in a power mobility device. Besides processing sensor data and other data analysis, Hoffman’s work also involves getting to know families, “playing with a lot of toys, singing, and entertaining kids,” she jokes.

Research involving pediatrics and accessibility like the adapted ride-on cars study is why Hoffman joined the Steele Lab. She became interested in biomechanics in sixth grade, when she learned that working on engineering and medical design was possible. As an undergraduate at the University of Notre Dame, Hoffman studied brain biomechanics, computational design and assistive technology. She worked on projects such as analyzing the morphology of monkey brains and creating 3D-printed prosthetic hands for children.

After connecting with Feldner and Kat Steele, Albert Kobayashi Professor in Mechanical Engineering and CREATE associate director, Hoffman realized that the Steele Lab, which often collaborates with UW Medicine, was the perfect fit.

Hoffman is currently working on research with Feldner and Steele that compares children’s usage of a commercial pediatric powered mobility device to their usage of adapted ride-on cars in the community environment. Next, Hoffman will conduct one of the first comparative studies about how using supported mobility in the form of a partial body weight support system or using a powered wheelchair affects children’s exploration patterns. The study involves children with Down Syndrome, who often have delayed motor development and who are underrepresented in mobility research.

There can be stigma associated with using a wheelchair instead of a walker or another mobility device that may help with motor development, but Hoffman says the study could demonstrate that both are important.

“The goal is to show that children can simultaneously work on motor gains while using powered wheelchairs or other mobility devices to explore their environment,” she says.

“Our hope is for kids to just be kids,” says Hoffman. “We want them to be mobile and experience life at the same time as their peers. It’s about meeting a kid where they’re at and supporting them so that they can move around and play with their friends and family.”


This article was excerpted from an article written by Lyra Fontaine for Mechanical Engineering.

Off to the Park: A Geospatial Investigation of Adapted Ride-on Car Usage

November 7, 2023

Adapted ride-on cars (ROC) are an affordable, power mobility training tool for young children with disabilities. But weather and adequate drive space create barriers to families’ adoption of their ROC. 

CREATE Ph.D. student Mia E. Hoffman is the lead author on a paper that investigates the relationship between the built environment and ROC usage.

Mia Hoffman smiling into the sun. She has long, blonde hair. Behind her is part of the UW campus with trees and brick buildings.

With her co-advisors Kat Steele and Heather A. Feldner, Jon E. Froehlich (all three CREATE associate directors), and Kyle N. Winfree as co-authors, Hoffman found that play sessions took place more often within the participants’ homes. But when the ROC was used outside, children engaged in longer play sessions, actively drove for a larger portion of the session, and covered greater distances.

Accessibility scores for the sidewalks near a participant’s home on the left and the drive path of the participant on the right. Participant generally avoided streets that were not accessible.

Most notably, they found that children drove more in pedestrian-friendly neighborhoods and when in proximity to accessible paths, demonstrating that providing an accessible place for a child to move, play, and explore is critical in helping a child and family adopt the mobility device into their daily life.

Augmented Reality to Support Accessibility

October 25, 2023

RASSAR – Room Accessibility and Safety Scan in Augmented Reality – is a novel smartphone-based prototype for semi-automatically identifying, categorizing, and localizing indoor accessibility and safety issues. With RASSAR, the user holds out their phone and scans a space. The tool uses LiDAR and camera data, real-time machine learning, and AR to construct a real-time model of the 3D scene, attempts to identify and classify known accessibility and safety issues, and visualizes potential problems overlaid in AR. 

RASSAR researchers envision the tool as an aid in the building and validation of new construction, planning renovations, or updating homes for health concerns, or for telehealth home visits with occupational therapists. UW News interviewed two CREATE Ph.D. students about their work on the project:


Augmented Reality to Support Accessibility

CREATE students Xia Su and Jae Lee, advised by CREATE Associate Director Jon Froehlich in the Makeability Lab, discuss their work using augmented reality to support accessibility. The Allen School Ph.D. students are presenting their work at ASSETS and UIST this year.

Illustration of a user holding a smartphone using the RASSAR prototype app to scan the room for accessibility issues.

UnlockedMaps provides real-time accessibility info for rail transit users

Congratulations to CREATE Ph.D. student Ather SharifOrson (Xuhai) Xu, and team for this great project on transit access! Together they developed UnlockedMaps, a web-based map that allows users to see in real time how accessible rail transit stations are in six metro areas including Seattle, Philadelphia (where the project was first conceived by Sharif and a friend at a hackathon), Chicago, Toronto, New York, and the California Bay Area.

screenshot of UnlockedMaps in New York. Stations that are labeled green are accessible while stations that are labeled orange are not accessible. Yellow stations have elevator outages reported.

Shown here is a screenshot of UnlockedMaps in New York. Stations that are labeled green are accessible while stations that are labeled orange are not accessible. Yellow stations have elevator outages reported.

Sharif, a UW doctoral student in the Paul G. Allen School of Computer Science & Engineering advised by CREATE Co-Director Jacob O. Wobbrock, said the team also included nearby and accessible restaurant and bathroom data. “I think restaurants and restrooms are two of the most common things that people look for when they plan their commute. But no other maps really let you filter those out by accessibility. You have to individually click on each restaurant and check if it’s accessible or not, using Google Maps. With UnlockedMaps, all that information is right there!”

Adapted from UW News interview with Ather Sharif. Read full article »

A Ph.D. Student’s Promising Research in Mobility in Cerebral Palsy

Whether she’s researching how biofeedback systems can guide gait training in children with cerebral palsy or leading toy adaptation events, Alyssa Spomer is committed to advancing accessible technology.

A Ph.D. student in UW Mechanical Engineering (ME) and advised by CREATE Associate Director Kat Steele, Spomer is the student chair of CREATE-sponsored HuskyADAPT. Her studies have been multidisciplinary, spanning ME and rehabilitation medicine. She uses her engineering skills to understand the efficacy of using robotic devices to target and improve neuromuscular control during walking.

“Delving into how the central nervous system controls movement and how these systems are impacted by brain injury has been such an interesting aspect of my work,” Spomer says. “My research is a mix of characterizing the capacity for individuals to adapt their motor control and movement patterns, and evaluating the efficacy of devices that may help advance gait rehabilitation.”

In her dissertation work, Spomer is primarily evaluating how individuals adapt movement patterns while using a pediatric robotic exoskeleton paired with an audiovisual biofeedback system that she helped design. The Biomtoum SPARK exoskeleton works to sense and support motion at the ankle during walking, using motors worn on a hip belt to provide either resistance or assistance to the ankles during walking. The audiovisual system is integrated into the device’s app and provides the user with real-time information on their ankle motion alongside a desired target to help guide movement correction.

Collage of two images. Left: Man walking on a treadmill wearing a robotic exoskeleton device around his hips and legs while a female researcher monitors the process through a tablet. Right: A closeup of the researcher's hands holding the tablet showing the real-time information.
The audiovisual system that Spomer helped design (shown on a screen in the right photo) provides the user with real-time information on their ankle motion alongside a desired target to help guide movement correction.

Inspired by CREATE’s Kat Steele and the Steele Lab

Spomer was drawn to ME by the Steele Lab’s focus on enhancing human mobility through engineering and design. Working with Kat Steele has been a highlight of her time at the UW.

“I really resonated with Kat’s approach to research,” Spomer says. “The body is the ultimate machine, meaning that we as engineers can apply much of our foundational curriculum in dynamics and control to characterize its function. The beauty of ME is that you are able to develop such a rich knowledge base with numerous applications which really prepares you to create and work in these multidisciplinary spaces.”

This winter, Spomer will begin a new job at Gillette Children’s Specialty Healthcare. She’s excited to pursue research that aligns with her Ph.D. work. Her goal remains the same: “How can we advance and improve the accessibility of healthcare strategies to help promote independent and long-term mobility?”

Excerpted from UW Mechanical Engineering, written by Lyra Fontaine with photos by Mark Stone, University of Washington. Read the full article

CREATE becomes a principal sponsor of HuskyADAPT

CREATE is pleased to be a financial and advisory sponsor of HuskyADAPT, an interdisciplinary community that is dedicated to improving the availability of accessible technology in Washington and fostering conversations about the importance of accessible design. 

HuskyADAPT is led by a team of UW students and six faculty advisors, including CREATE directors Kat SteeleHeather FeldnerAnat Caspi and Jennifer Mankoff. Open to all to join, their three primary focus areas are annual design projects, K-12 outreach and toy adaptation workshops, where volunteers learn how to modify off-the-shelf toys to make them switch accessible. The team also collaborates closely with Go Baby Go!.

Sign up for HuskyADAPT’s newsletter

HuskyADAPT logo, with 3 heaxagons containing icons of tools, people and vehicles.

Feldner and Steele’s ‘Reimagining Mobility’ series featured in The Daily

Collaboration and diverse perspectives and approaches are at the heart of CREATE’s mission to make technology accessible and make the world accessible though technology.

One program developed by CREATE faculty looks at mobility solutions and ways to eliminate barriers. Hosted by CREATE associate directors Kat Steele and Heather Feldner, the Reimagining Mobility Conversation Hub brings in speakers from a variety of backgrounds and industries to inspire conversations about the future of mobility.

The UW student newspaper, The Daily, featured the program in Reimagining Mobility: Professors Amplify Disabled Voices in the November 15 2021 issue.

Headshot of Kat Steele, smiling warmly. She is a white woman with long brown hair.

Working at a children’s hospital made me want to grow my knowledge as an engineer. There was just this disconnect of how we thought about technology, how we thought about what was possible, and what was actually available.

Dr. Kat Steele, CREATE Associate Director and Albert S. Kobayashi Endowed Professor of Mechanical Engineering.

Headshot of Heather Feldner, smiling brightly. She is a white woman with short brown and grey hair, and wears dark rimmed glasses, a gray shirt and black sweater.

How we move around really impacts our social relationships. It impacts our ability to participate in school, in jobs, in social events — it’s really one of our major connections to the world. The end goal of mobility is to engage in our lives and participate meaningfully.

Dr. Heather Feldner, CREATE Associate Director and
Assistant Professor, Rehabilitation Medicine: Physical Therapy

Reimagining Mobility: Inclusive Architecture

On October 13, 2021 Karen Braitmayer shared images from her experience of— and critical goals for— inclusive architecture. Noting that the best and brightest designers might come in bodies that are different than employers expect, she called for design schools to welcome students with disabilities and for design firms to hire and support the careers of designers with disabilities.

First steps for designers:

  • Provide options: wider seats, different height soap dispensers, etc.
  • Learn about building codes and regulations.
  • Talk to folks who have already figured out how to accommodate for their own disabilities and hack for accessibility.

Sign up for the Conversations

Karen Braitmayer using a wheelchair in a modern building with stairs and ramps

Architect Karen L. Braitmayer, FAIA, is the founding principal of Studio Pacifica, an accessibility consulting firm based in Seattle, Washington. Her “good fight” has consistently focused on supporting equity and full inclusion for persons with disabilities.

In 2019, she was chosen as the national winner of the AIA Whitney M. Young, Jr. award—a prestigious award given to an architect who “embodies social responsibility and actively addresses a relevant issue”. In the award’s 48-year history, she was the first recipient honored for their work in the area of civil rights for persons with disabilities. Braitmayer was also appointed by President Barack Obama to the United States Access Board, a position she retains today.


Join the Reimagining Mobility conversation

Join us for a series of conversations imagining the future of mobility. Hosted by CREATE Associate Directors Kat Steele and Heather Feldner, we connect and learn from guests who are engaged in critical mobility work – ranging from researchers to small business owners to self-advocates. We will dive deeply into conversations about mobility as a multifaceted concept, and explore how it intersects with other dimensions of access across contexts of research, education, and public policy. 

Sign up for the Conversations

Can Project Sidewalk Use Crowdsourcing to Help Seattleites Get Around?

July 23, 2019 | SeattleMet

With the goal of making navigating our streets safer and easier for the mobility impaired, Jon Froehlich’s Project Sidewalk turns mapping sidewalks and improving pedestrian accessibility into a virtual game. To complete missions, users “walk” through city streets via Google Street View, labeling and rating the quality of sidewalks and features that make it easier—or tougher—to get around. They identify curb ramps, or lack thereof, assess their positioning, and point out tripping hazards.

Since Froehlich launched Project Sidewalk in Seattle in April 2019, users have mapped roughly a third of the city’s 2,300 miles of sidewalks and labeled nearly 70,000 curb ramps, uneven surfaces, potential obstacles like lamp posts, too.

Read the full SeattleMet article.