Wheelchair-bound patients have the ability to climb stairs and elevate to standing position. The U.S. Food and Drug Administration approved a battery-powered stair-climbing wheelchair on August 13, 2003. The wheelchair, called the INDEPENDENCE iBOT Mobility System, relies on a computerized system of sensors, gyroscopes, and electric motors to allow for indoor/outdoor use on stairs, and also on level and uneven surfaces. (Note: In 2009, Independence Technology stopped selling the iBOT, but support for existing units was available until the end of 2013. In 2010, a group was trying to revive the manufacturing of the INDEPENDENCE iBOT.)
Stair-Climbing Wheelchair Features
The potential benefit for the estimated 2 million people who are wheelchair users in the United States is exciting. The user of the new breakthrough wheelchair, the iBOT, can command the wheelchair in different ways by the push of a button. The iBOT can be converted from a standard chair with four wheels contacting the ground to an elevated chair balanced on only two wheels. The iBOT can engage four-wheel drive to maneuver rough terrain, go up slopes, or climb 4-inch curbs. For stair-climbing, there are two sets of drive wheels that rotate up and over reach other to climb up or down, one step at a time. The unique balancing system allows the wheelchair to remain stable and the seat to stay level during all of the aforementioned maneuvers.
To climb up the stairs:
- The user backs up to the first step and holds on to the stair railing.
- The user shifts his weight over the rear wheels, causing the chair to begin rotation of the front wheels up over the rear wheels and then down onto the first step.
- As the user shifts his weight backward and forward, the chair senses this and adjusts wheel position to keep the user's center of gravity under the wheels.
- The chair ascends stairs backwards, and descends stairs forward - therefore the user always faces down the stairs.
To reach high shelves or hold eye-level conversations:
- The wheelchair user shifts his weight over the back wheels so iBOT lifts one pair of wheels off the ground and balances on the remaining pair of wheels.
- The user presses a button to lift the seat to a higher position.
Stair-Climbing Wheelchair Precautions
People must not weigh more than 250 pounds and must have use of at least one arm to operate iBOT. Good judgement skills are necessary too, so the user can decide which obstacles should be avoided in order to prevent falls. The user must be capable of some exertion when climbing stairs with iBOT by themselves. There is a feature, however, which allows someone else to hold onto and tilt the chair back, causing it to climb up or down stairs.
Physicians and other health professionals must have special training in order to be able to prescribe iBOT. The chair must be calibrated for the user's weight, and patients who will be users must be trained in its use and also pass physical, cognitive, and perception tests to prove they can operate iBOT safely.
Dean Kamen, an inventor who is well known for the Segway scooter, created iBOT and licensed it to Johnson and Johnson.
To prove iBOT works:
- 18 wheelchair users test drove iBOT for 2 weeks.
- Scientists compared maneuverability in iBOT versus regular wheelchairs in everyday situations and special road tests.
- 12 patients navigated stairs alone with iBOT. 6 patients used an assistant.
- In regular wheelchairs, one patient could bump his way down stairs, while no one could go up a single step.
- 3 people fell out of iBOT. 2 people fell out of their own wheelchairs during the study. None of the incidents occurred on stairs and no one was seriously injured.
As a condition of FDA approval, the manufacturer agreed to periodically report to the FDA and document the chair's usage, functioning, and any patient injuries.