By Laura Spitznogle and Shannon Sheehan

 

 

Physical therapy graduate student Misty Smith helps during the
testing phase of the Mountaineer Mover. She is using the device
for three three-minute periods. The wheelchair, set on a stationary
surface, is set to provide the resistance of a slight grade
(as opposed to a flat or uneven surface). During the last minute
of each session, she is hooked up to an oxygen sensor that will
monitor the level of oxygen she is using. Smith will return later
to complete the same test, but without the Mountaineer Mover
attached to the chair. All of this data, along with other vital signs, the
student's opinion of difficulty, and much more will be compared and
analyzed to determine the feasibility of production of the mechanism.

 

WEST VIRGINIA has the highest per capita rate of handicapped citizens in the country, but we rarely see them. Why? Because of the mountainous terrain. It's virtually impossible to guide a manual wheelchair from the Beechurst PRT station to the Mountainlair. Or to go from the downtown campus to a house in Sunnyside. It's easier to stay home.

Of course, the Mountains aren't limited to Morgantown; West Virginia is "The Mountain State," after all. We don't see the mobility impaired because they can't negotiate the hills and valleys that make our state unique and beautiful. Wheelchair users who live in flatter terrain have other navigation problems such as uneven sidewalks, sand, ice, or even thick carpeting.

The mechanics of a wheelchair are fairly simple. You use your arms to push the large wheels forward. This repetitive asymmetric motion of the arms, however, can cause injury. Rotator cuff injuries and carpal tunnel (both of which often require surgery to repair) are common among wheelchair users.

Despite those obstacles, the wheelchair has been called the most important technological innovation of the 20th century. It allows mobility-challenged people to hold a job, go to the grocery store, and to live productive and satisfying lives. In 1997, there were over 1.5 million wheelchair users nationwide.

The Concept
Dr. Al Stiller, professor of chemical engineering in WVU's College of Engineering and Mineral Resources, is not your average professor. He likes to teach. He loves to tinker and invent new stuff. Stuff that brings in research dollars to the University and has some benefit to the state of West Virginia.

His latest creation is a the Mountaineer Mover. No, it's not a new addition to the PRT. It's a device that makes wheelchairs more efficient.

The idea came to him one day as he was riding a mountain bike up the monstrous hill on Beechurst Avenue that eventually leads to the Engineering Sciences Building. He began to perspire and he didn't like it. He figured he could make the bike ten percent more efficient so he wouldn't have to pedal so hard. So he did. He created a device that used the linear motion of his legs to move the bike. He could then pedal up the hill without a drop of sweat on his brow.

Stiller thought there must be some practical application for his newest invention. It didn't take him very long to figure out that it would work for wheelchairs too (with modification, of course). He then enlisted the help of Dr. Tom Long and graduate student Scott Wayne. Together, they designed a device which could be attached to a wheelchair and would help propel the machine more efficiently, therefore reducing the risk of injury to the operator and increasing the mobility of the handicapped.

The Design
The Mountaineer Mover attaches to a standard wheelchair and allows the user to propel the chair in both the push and pull strokes of the handle. Therefore, power is produced during the entire stroke, and not just in one direction as with a regular wheelchair.

The mechanism works by employing a lever-actuated elliptical input motion and a Cardan gear system that changes the elliptical input into rotary output. A Cardan gear mechanism is a hypocycloidal gear train that is used to convert rotation (circular motion) into straight-line motion.

The device permits propulsion with minimal grip changes (important for people with neurodegenerative handicaps, i.e., muscular dystrophy) and offers a variety of hand positions to accommodate a wider range of impairments. It weighs less than ten pounds and does not add more than two inches to the width of a wheelchair.

The lever position can be changed on the wheelchair to meet the comfort needs of the user, and its simple construction can be retrofitted onto existing wheelchairs.

Testing
The device has gone from concept to design to testing. Now, the researchers need concrete data on how their new device will help propel a wheelchair.

The data should show that the chair has a real benefit and is safe. It will also provide feedback from some physical therapists and potential end users. This is key information that wheelchair manufacturers must have before they will consider producing the chair.

During testing, a wheelchair, fitted with the new device, is hooked up to a dynamometer (a machine that allows for a load to be applied as a torque on a shaft). As a person propels the wheelchair, monitors record vital signs that are then compared to data from normal wheelchair propulsion. The preliminary data showed gains in energy, horsepower, and RPM ratio with the new device.

This assistive technology reduces the stress that is normally placed on the upper extremities during propulsion of a standard wheelchair, and amplifies the user's force by approximately 50 percent. The tests also show that the simple elliptical path created by the new device produces fewer injuries to the shoulder and arm than the stroke used by typical wheelchair users. The user will not have the asymmetric muscle development associated with standard wheelchair propulsion, making the device beneficial to almost all wheelchair users.

Production
Before inventions like the Mountaineer Mover reach the end user, a long road of assessment and development must be traveled. At WVU, new inventions are submitted to the Office of Technology Transfer. There, inventions are assessed for their technical, commercial, and intellectual property merits.
Assessment determines if a commitment will be made to market the creation and pursue intellectual property protection, usually a patent. If the technology appears technically unfeasible or if no market exists for the end product, then there is little chance that further resources will be expended on the invention.

In the case of the wheelchair, the technology was sound, and the prototype showed this. It was clear that a few refinements could make the chair lighter, more efficient, and improve manufacturability.

Market research indicated a need for this kind of chair not only in low-income areas where motorized chairs are not an option, but also with any wheelchair users who wants the benefits of less wear and tear on the body.

A local company, Swanson, showed an interest in producing and selling the wheelchair. Swanson had originally been involved with Stiller and company because of their involvement in building the prototype. This emphasizes the importance of the collaboration between the University and local companies not only to develop useful technology but also to initiate projects that will bring jobs to West Virginia. Swanson was not willing to make a commitment to produce and sell the chair until the physiology data on the chair was collected. This collection is now under way.

Market research also revealed that in 1999 about $1.5 billion was spent on wheelchairs worldwide. Additionally, wheelchairs are produced by a number of small companies. This indicated that a small local firm like Swanson would be an excellent venue to make and sell the final chair.

Before the chair was demonstrated to outsiders or graduate committees, care was taken to protect its confidentiality. Through confidentiality agreements and finally a patent, the Office of Technology Transfer made sure that the intellectual property rights to the wheelchair were protected.

Why patent something as altruistic as a wheelchair? If no patents are filed on an invention at the time it is shown to the public, then that invention becomes public property for all to use. History has shown that once no specific party owns an invention, there is then no incentive for any one potential company to make the investment to develop and take it to market. This is because they could never recoup their costs to develop and market the technology.

Impact
Even though the device is still in testing stages, Jess Mancini, a quadriplegic and assistant dean of WVU's College of Business and Economics, can't wait to try it: "I might be able to forego the electric wheelchair for everyday use. Using a manual wheelchair would improve my muscular and cardiovascular health."

"I don't get to design much stuff that directly impacts on the people of West Virginia," said Stiller. "The quality of life of these citizens will be changed." And what an impact this new device could have for the handicapped community that lives within the state. A product that was conceptualized, designed, and tested at WVU, and built by an in-state company could allow handicapped people to lead healthier and more independent lives.

 

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