What Can An Xbox Controller Teach Us About Improving Power Wheelchairs?

Dec 21, 2010

The University of Texas system is filled with experts researching a wide range of topics, but coordinating them to help the tens of thousands of Texans living with physical disabilities is no easy task. Just ask UT Health professor Lex Frieden. He was handed that responsibility at the beginning of the month. But says he is up for the job. Lex has lived in a wheelchair most of his life, and was one of the architects of the Americans with Disabilities Act.

One of the projects Frieden is working on with undergrad engineering students at UT Austin involves figuring out how to improve on the electric wheelchair. Dr. Frieden talked to KUT News about it.

KUT News: One of your projects involves cooperating with engineering students at UT Austin to enhance the control mechanisms of electric wheelchairs. Can you tell us about that?

Lex Frieden: Largely, power wheelchairs are being guided by the same sort of joystick control that has been used for 20 years since the first power wheelchair was built. It's a very simple, basic, electromechanical control that you push one way or the other depending on which way you wish to move.

This particular mechanism is used all over the world. It's connected by wires to a motor and a battery and controlling modules. It's very basic. It's very simplistic. It will not accommodate people with disabilities who have difficulty moving their wrist or their hands or their fingers. It will not accommodate people with disabilities who have paralysis in their upper extremities. It will not accommodate people who have other kinds of limitations. It's very, very basic.

Yet our technology has grown far beyond that. We use more sophisticated control mechanisms for playing Xbox games and guiding aircraft in the backyard that hobbiests use. Xbox controllers use a wireless system, but most power wheelchairs don't. We need to harness that technology to make wheelchairs lighter.

Or look at the accelerometer in your iPhone. It measures when you tilt your iPhone in different directions. Why can't you drive a powered wheelchair with an iPhone?

Students from the engineering school at the University of Texas at Austin have begun to work on a project to design a new, more up-to-date control mechanism for powered wheelchairs. I think it's an interesting endeavor.

KUT News: What does the future hold for power wheelchairs?

Frieden: Power wheelchairs could benefit from a lot of development. They're equipped with the same kind of batteries used to start car motors, yet we're using far more efficient batteries to operate our cell phones. These new lithium style batteries could be used in wheelchairs to make them more compact, to hold charges longer, to make the wheelchair run longer between charges, and perhaps to drive it faster.

The motors that are used in the wheelchairs are the same ones often used in factories to drive trolleys and other big equipment. The motors could be designed to be lighter, more efficient, and move heavier loads faster. There's a whole lot that can be done with the mechanics.

From an ergonomic standpoint, seating in wheelchairs has never been much of a priority because the people designing the wheelchairs have largely been mechanical engineers. We believe that the ergonomics can be improved dramatically if we use the same engineers, scientists, and designers who are working on, let's say, first class travel in airplanes, or the kinds of recliners we have in our homes where we watch television for extended hours. A lot of that seating design needs to be applied to wheelchairs.

KUT News: Surprising this science hasn't been applied to wheelchairs already. Why does it take some UT undergrads to get the ball rolling?

Frieden: It's a good question. It's part of the question I hope they answer in the next year by consulting with administrators and faculty members throughout the system. Hopefully we can come to some agreement on designs and collaborations that will enable us, at least in Texas, to make some breakthroughs like those students are apt to do there at UT in Austin.