Motorized wheelchair
An electric powered wheelchair, commonly called a "power wheelchair" is a wheelchair which additionally incorporates batteries and electric motors into the frame and that is controlled by either the user or an attendant, most commonly via a small joystick mounted on the armrest, or on the upper rear of the frame. For users who cannot manage a manual joystick, hand switches, chin-operated joysticks, sip-and-puff Remote controllers or other specialist controls may allow independent operation of the
karma power wheelchair. Ranges of over 10 miles/15 km are commonly available from standard batteries.
Power wheelchairs are commonly divided by their access capabilities. An indoor-wheelchair may only reliably be able to cross completely flat surfaces, limiting them to household use. An indoor-outdoor wheelchair is less limited but may have restricted range or ability to deal with slopes or uneven surfaces. An outdoor
Visco power wheelchair is more capable, but will still have a very restricted ability to deal with rough terrain. A very few specialist designs offer a true cross-country capability.
Power wheelchairs have access to the full range of wheelchair options, including ones which are difficult to provide in an unpowered manual chair but have the disadvantage of significant extra weight. Where an ultra-lightweight manual chair may weigh under 10 kg, the largest outdoor power-chairs may weigh 200 kg or more.
Smaller power wheelchairs often have four wheels, with front or rear wheel drive, but large outdoor designs commonly have six wheels, with small wheels at front and rear and somewhat larger powered wheels in the center.
A power-assisted wheelchair is a recent development that uses the frame & seating of a typical rigid manual chair while replacing the standard rear wheels with wheels of similar size which incorporate batteries and battery-powered motors in the hubs. A floating rim design senses the pressure applied by the user's push & activates the motors proportionately to provide a power assist. This results in the convenience, and small size of a manual chair while providing motorized assistance for rough/uneven terrain & steep slopes that would otherwise be difficult or impossible to navigate, especially by those with limited upper-body function. As the wheels necessarily come at a weight penalty it is often possible to exchange them with standard wheels to match the capabilities of the wheelchair to the current activity.
Mobility scooters
Mobility scooters share some features with power wheelchairs, but primarily address a different market segment, people with a limited ability to walk, but who might not otherwise consider themselves disabled. Smaller mobility scooters are typically three-wheeled, with a base on which is mounted a basic seat at the rear, with a control tiller at the front. Larger scooters are frequently four-wheeled, with a much more substantial seat.
Opinions are often polarized as to whether karma mobility scooters should be considered wheelchairs or not, and negative stereotyping of scooter users is worse than for manual or power wheelchair users. Some commercial organizations draw a distinction between karma power wheelchairs and scooters when making access provisions due to a lack of clarity in the law as to whether scooters fall under the same equality legislation as wheelchairs.
