Wheels Designed in 3D Improve Wheelchair Mobility

21 Nov, 2007 By: Michelle Nicolson

Steve Meginniss describes himself as an early adapter of CAD technology. He bought his first AutoCAD 1.15 program in the mid-1980s and hasn't looked back since. A successful inventor, he has used Autodesk applications to design products that are now common personal appliances you are likely to find in your bathroom, including the Sonicare toothbrush and the Clarisonic skin care brush.

Always looking for a new challenge, Meginniss stumbled upon a potential market in the mid-1990s that was previously unknown to him. Working with the University of Washington on prospective mobility projects, he discovered that manual wheelchairs have quick-release axles that allow the standard drive wheels to be replaced with different types of wheels. Meginniss also learned that, overall, manual wheelchairs have changed very little since being patented in 1869. Hand rims and wheels remain much the same, and the chairs have only one speed.

Meginniss set out to change that fact by designing mechanical wheels that would provide the user with two easily shifted gears for mobility enhancement to navigate ramps, hills, and rough terrain as well as with an automatic hill holding with override feature in the lower gear that prevents the wheelchair from rolling backward on inclines. And with that simple idea, he began a 10-year journey to create MAGICWHEELS.

A manual wheelchair with the MAGICWHEELS product installed.

The Challenge of Complex Surfaces
Similar to the technology found on bicycles, the concept behind MAGICWHEELS is simple, but the product itself comprises a multitude of complex surfaces. After years of using AutoCAD and then learning 3D in Mechanical Desktop, Meginniss implemented Autodesk Inventor when his company became operational in 2001 and his team designed the final MAGICWHEELS product in this program. The appeals of Inventor are advanced surfacing modeling and animation capabilities, Meginniss explained.

"It's almost impossible to do something like MAGICWHEELS' two-gear drive without a 3D CAD system because many precision parts have to nest together," he said. "Many times we found parts interfered with the shifting system. Inventor has a system where you can animate it, and it will show the interferences."

A 3D model of the MAGICWHEELS shifting system in Inventor.

Inventor's capability revealed interferences, which proved to be a key element when it came time to move from design to prototype. "We were able to make these complex surfaces and transfer them into the mold maker's CAM software without any problems," Meginniss said. "I had another project where we had solid models that didn't fit together correctly. We had to have them all done over. I was impressed that we could build these models in Inventor and get them into CAM systems without any trouble."

Learning Curve
The Magic Wheels team learned Inventor while designing the final version of Magic Wheels' product, an effective but challenging way to learn the program. "It was brutal at times," he admitted. "But the team got good support from the local Autodesk reseller."

Once the product was finally ready for testing, Meginniss discovered more surprising elements about his new market. Manual wheelchair users frequently suffer from shoulder pain because of the physical stress of controlling their wheelchairs with their upper bodies. Although originally designed to increase the mobility of manual wheelchairs, Magic Wheels' two-gear drives have been found to reduce that pain by 55%, according to a study by the University of Maryland, School of Medicine.

"This makes a real difference in people's lives," Meginniss said. "Our end users just love them."

Barry Long, an early tester for the Magic Wheels company, demonstrates the hill holding feature of MAGICWHEELS.

As such, Meginniss and his Magic Wheels team of nine employees value the nonmonetary rewards for their hard work. "Our products help people get to work and maintain jobs and other activities of daily living," Meginniss said. "We have a couple of weaker users that have become mobile with MAGICWHEELS. They are now able to get into vans independently and drive around."

The MAGICWHEELS product was officially launched into the market last year. It's already won a 2007 Silver IDEA award from BusinessWeek, and the enthusiastic praise from early adopters continues. The company also helps its customers with medical insurance claims, and Medicare has recently started covering the purchase of the product for eligible customers.

"We recently hired a new CEO to run the business," Meginniss chuckled. "My tendency was, if anyone truly needed a set, just give it to them."

Harnessing the power of 3D CAD in Inventor is one thing Meginniss is quite pleased about. He believes the technology has proven advantageous for the Magic Wheels company.

"The difference between 2D and 3D is so compelling that I can't imagine anyone sticking with 2D," he reflected. "It's not that hard to use 3D once you learn it."

An online video demonstrates the features of MAGICWHEELS.

About the Author: Michelle Nicolson

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