Medical Equipment

New Wheelchair Keeps People on the Move

By Carol Rados

Imagine losing use of your legs, and still being able to stand up. It's possible, with a new self-propelled wheelchair that knows how to keep its balance.

The Independence iBOT 3000 Mobility System is a battery-operated wheelchair that will enable people with mobility impairments to go up and down stairs, reach high shelves, climb curbs, travel over a wide variety of terrain, negotiate uneven or inclined surfaces, and hold eye-level conversations with others who are standing.

The Food and Drug Administration expedited review of the iBOT because it represents a breakthrough technology with the potential to benefit people with disabilities. "Its approval is emblematic of FDA's commitment to help innovative medical technologies reach patients promptly," says FDA Commissioner Mark B. McClellan, M.D., Ph.D. According to the FDA, which approved the device in August 2003, an estimated 2 million Americans use wheelchairs.

Powered by a rechargeable battery that can operate up to a full day on a single charge, the wheelchair uses an integrated system of software, sensors, and electronics to automatically adjust itself according to the seat's movement and the user's center of gravity.

To select the mode of operation, the user pushes a button to command either standard, 4-wheel drive, balance, stair climbing, or remote functions. A joystick controls the speed and direction of travel. The iBOT can be easily converted from a standard chair, with four wheels in contact with the ground, to an elevated chair balanced on only two wheels. This allows the user to reach high objects or to be at eye level for conversations. The user shifts his or her weight over the back wheels and the iBOT system responds by lifting one pair of wheels off the ground, while balancing on the other pair of wheels.

Four-wheel drive enables the user to traverse rough terrain, travel over gravel or sand, go up slopes, and climb four-inch curbs. Because of its unique balancing mechanism, the wheelchair remains stable and the seat stays nearly level during all these maneuvers. For use on stairs, there are two sets of drive wheels that rotate up and over each other to climb up or down, one step at a time. When operating on stairs, users lean forward or backward, directing the chair to go up or down.

The iBOT isn't for everyone, however. The chair is available only with a doctor's prescription, and people must have use of at least one arm to maneuver it. The chair also must be calibrated to the patient's weight, which is limited to no more than 250 pounds, and users must undergo special training. Using the wheelchair requires some physical effort, and users must have the skills and judgment to constantly assess the environment and choose between different travel routes and device functions. Although the chair is priced at about $29,000, people who buy the iBOT may escape the costs of typical wheelchair modifications, such as ramps and elevators, needed for home use.

As a condition of approval, the iBOT's manufacturer, Independence Technology of Warren, N.J., a Johnson & Johnson company, has agreed to report periodically to the FDA with updates on the chair's usage, functioning, and any injuries that may occur.

iBOT Modes of Operation