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Designing a waterproof, air-powered wheelchair that lets everyone enjoy the water

Q:  What uses no batteries, runs on air, and is designed to let everyone splash around in a water park?

A:  A waterproof, air-powered wheelchair called the PneuChair.

Mark Villanueva, a Morgan’s Inspiration Island employee, tried out the PneuChair. The water park was the first location to use the wheelchair. Image Credit: The University of Pittsburgh.

Mobility and accessibility. For many people with disabilities, the mobility provided by powered wheelchairs has greatly expanded accessibility, enabling them to work, shop, and travel independently. But the electronics and the battery-powered nature of these devices mean they shouldn’t get wet. Using an electric-powered wheelchair in downpours or on a street strewn with puddles can be problematic, let alone using one at a beach or a pool. Accessibility is still limited.

Now, there is a powered wheelchair that can get wet. Researchers from the Human Engineering Research Laboratories, (HERL) have created the PneuChair, a pneumatic wheelchair that replaces the traditional battery energy source with high-pressure air. PneuChair is waterproof, meaning downpours won’t be an issue at all. In fact, it is completely submersible. It can be used at lakes, at the beach, and even in swimming pools. It’s also perfect for water parks.

Last summer, the world’s first fully-accessible water park opened in Texas. The park is designed to let children of all abilities play and splash together. Morgan’s Inspiration Island is a park where special needs children (and adults!) won’t encounter attractions they can’t access. The park was also the first location to use PneuChair wheelchairs.

“What we’ve already seen is that it does work,” Gordon Hartman, the creator of Morgan’s Inspiration Island, told CNN. “We’ve had children of severe special needs playing alongside other children in a water environment.”

Designing a pneumatic wheelchair

Dr. Rory Cooper, the director of the HERL, and his team designed and built the PneuChair. The PneuChair runs on 4,500 psi compressed air, removing the need for batteries and electronics. The carbon-fiber air canisters power rotary piston motors to turn the wheels. In addition to being waterproof, it is significantly lighter than most powered wheelchairs. It also takes only 10 minutes to charge, whereas typical powered chairs require 8 hours.

Image Credit: Michael Lain/HERL

 

The chair is also less expensive to maintain and never needs a replacement battery. Brandon Daveler, the lead mechanical design engineer on the project, stated, “The PneuChair uses a simpler design without a lot of electronics and software. If something goes wrong, any of the components can be purchased at your local hardware store.”

While the resulting design is simpler, the design process had to account for many factors. Key among them was the control of the unit as it was propelled by the compressed air.

MATLAB was used for several aspects of the PneuChair project,” stated Cooper. “Initially, we used MATLAB to simulate the control and to analyze test data within‎ the laboratory. MATLAB was also used for visualization of the data.”

“It’s about inclusion”

The New York Times recently profiled Morgan’s Inspiration Island and the PneuChair. In the article, there’s a video worth watching, showing just how much joy inclusion can bring.

“All the things that people want to do — water parks, wave pools, beaches, wade into the water to go fishing, super-soaker fights in the front yard, water balloon fights — it reminds me just how much both water and fun have a part in our life and how much that’s truly missed by people when they have to use powered mobility devices,” Cooper told The New York Times.

“I’m not even sure that the people that are now using the PneuChair in Morgan’s Inspiration Island or that have tried the chair here in Pittsburgh realized how much they missed being able to do those things, or how much their family wished that they could be included in those things — until a solution was available,” he continued. “It’s not only about fun, it’s actually about being part of the community, and about inclusion.”

 

HERL Director Dr. Rory Cooper (right) with U.S. Secretary of Veterans Affairs Dr. David Shulkin. Sec. Shulkin is riding the PneuScooter. Image Credit: Michael Lain/HERL.

 

Designing a waterproof powered wheelchair was the main goal, but the design’s resulting lighter weight and faster charging were also useful features. The lighter weight helps extend its range: It can travel 3 miles between charges. The reduced charging time makes it easier to maintain a fleet of powered chairs that are ready for use. The PneuChair is a great candidate for stores and eldercare facilities that must charge and maintain a fleet of chairs. A scooter version, seen above, is also being developed.

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