A better wheel

Apparently you can re-invent the wheel. It just takes a lot of engineering. Maddak Inc. introduced the first-ever collapsible wheelchair wheel in March 2013. Morph Wheels fit any manual wheelchair and can fold into almost half its size, making travel, transfers, and everyday activities more convenient. The company and clinicians alike say the product could set a new standard in wheelchair wheel technology.
 

Academic experiment

The wheel was originally developed for bicycles by Duncan Fitzsimmons when he was a graduate student at the Royal College of Arts in London. The wheelchair community caught wind of the project from local media coverage and asked him to remake it for wheelchairs. When Kathleen Hanek, Maddak’s director of project management, learned about the redesigned foldable wheel from press reports, she contacted Fitzsimmons about collaboration.

“The original design was made out of metal, which made it extremely heavy [and] also extremely expensive to make,” Hanek explains. “Our goal was to take his design and then transfer it into plastics.”

Hanek adds that the New Jersey company teamed up with Fitzsimmons to make his wheel more manufacturable and marketable.

“It was really a matter of saying we need to not only create a wheel that folds, but we need to create a wheel that folds, and once it’s attached onto the wheelchair when someone’s using it, it feels and rolls like a normal wheel,” Hanek says. “We need to design a wheel that folds that somebody’s going to want to use.”
 

Meeting standards

It took an engineering design team at Maddak approximately three years to package Fitzsimmons’ original design into something that could pass rigorous safety tests. Wheelchairs are held to American National Standards Institute (ANSI) standards, which measure durability and performance and are written by members of the Rehab Engineering Society of North America (RESNA). The ANSI/RESNA tests use a dummy to replicate a human sitting in the chair and simulate five years of use. For example, a double-drum test moves the wheelchair across two rotating barrel drums and a durability test drops the wheelchair off a 4" curb 6,666 times.

Hanek says the Morph Wheels went through each challenge that a wheelchair has to pass. At first, it didn’t go well. The wheels, made of a glass-nylon material, had a “strange weight balance,” according to Hanek. Although they performed well during the curb-drop and double-drum tests, they “potato chipped” during a lateral stability test.

“We knew clearly it was not strong enough,” Hanek says. “We needed to add a little bit more ribbing to it, a little bit more stiffness of the plastic to it.”

To figure out just how much ribbing the wheels needed, Maddak’s team contacted an outside material expert, who suggested using material made of 30% glass, 70% nylon. After implementing the new material, Maddak tested its news design through computer-simulated modeling. When the engineers saw it work, they went ahead with production tooling and manufactured the wheel.

“In the end, it passed all the testing it needed to,” says Hanek.
 

‘An engineering feat’

The Morph Wheels are an engineering feat, Hanek says. Maddak engineers took a design that began as an academic experiment and turned it into a product with not just mass appeal, but with an acute purpose.

But to Dwight Atkinson, the Morph Wheels are something more.

“When I saw the wheel, I was like, this is really impressive because the wheel has been on planet Earth for more than 7,000 years, and it has not changed in design whatsoever,” Atkinson says. “This group has taken the wheel and redefined it. They’ve changed it. It’s mindboggling to me.”

Atkinson is a 16-year veteran of the medical device industry with a litany of titles under his belt: He’s been an owner/operator, worked for manufacturers, and practiced as an occupational therapist. Currently, he acts as Maddak’s sales manager, educating outside clinicians about Morph Wheels.

Both Atkinson and Hanek credit the unique hub of the wheel for carrying the most innovations. The hub’s engineering and safety features work together to protect users from sudden wheel compressions while providing them the functional ride of any high-shelf wheel.

One of the most important parts of the hub is its quick-release axle, which allows users to attach and detach the wheel. The axle uses a standard design that is already familiar to wheelchair users.

However, it also acts as a safety device as the wheel rolls. Hanek emphatically asserts that as long as the axle is through the hub of the wheel, which it has to be in order for the wheel to touch the wheelchair, “the wheel absolutely cannot fold.”

“That’s a huge safety feature,” Atkinson adds. “And that’s a pretty tough thing to do. Nobody else has done that.”

Maddak used focus groups to include other features on the wheel. For example, an automatic stop prevents the axle from coming loose from the wheel, ensuring wheelchair users can’t lose it. When the axle is out, wheelchair users simply follow a few steps to fold the wheel. When compressed, the wheel’s diminutive dimensions store comfortably into spaces as small as airplane overhead bins.
 

Setting new standards

During its brief life, the Morph Wheels have won enough awards to fill a trophy case. It won the transport category at the London Design Museum design of the year awards 2013, and Popular Science recently listed it as the Best of What’s New in its health category.

Hanek says the reaction has been overwhelming at tradeshows and conventions as well. At a RESNA tradeshow, full of the designers and engineers who wrote the ANSI standards, attendees “marveled at the wheel,” Hanek says.

“I heard from one person [who] was really happy there was a technology that was functional, that was useful, and that wasn’t just based on how light we can make something. It was really based on how can we better somebody’s life.”

Atkinson has had similar responses from patients and therapists.

“It’s very interesting to see patients’ reactions, especially when they see the wheelchair unfold,” he says. “They’re like, ‘What!’ It’s pretty exciting.

“They love the function that it brings and the independence that it increases for the patient population that’s very active. They really believe, and I believe this too, that this is going to be a standard from now to the next 5 to 10 years for what wheelchair wheels should have.”

And the engineers at Maddak are working to improve that standard. Immediate goals include expanding diameters beyond the currently offered 24", but Hanek says Maddak is using insights from the wheelchair community to focus the next developments.

“It’s not designed in a vacuum,” she explains. “It’s getting the product out on the market, getting users to use it, and letting them tell us where we need to go next. And all the technology we have is a great basis to get to the next level.”

Maddak Inc.
www.maddak.com

About the author: Danny English is associate editor for TMD and can be reached at denglish@gie.net or 330.523.5354.

Watch: Kathleen Hanek says three components play key roles in the folding/unfolding process: a silver metal spoke; a blue locking device; and a quick-release axle. To watch a video of how these three parts play into the process, visit http://bit.ly/1c1mIzU.