There are three types of power drives available to choose from;
Each (type) has its own purpose and advantages, depending on what the user needs a power wheelchair for. For example, some are more suited for indoors, some for outdoors. Source: Karma Medical
Front-Wheel drive power wheelchair
Front-wheel drive wheelchairs have larger front wheels that power the wheelchair, and two smaller wheelchairs on the rear. The larger front wheels are excellent at obstacle climbing and therefore mainly for outdoor use. Front-wheel drive wheelchairs have a small turning radius and the option to equip any footrest configuration because the front wheels do not rotate from side to side.
What is a turning radius?
The turning radius is the smallest radius a wheelchair can be turned for 360° in one constant forward drive with maximum steering effect. When choosing a power wheelchair, this is something that should be taken into account, especially if the user plans to use their power wheelchair indoors where space is often limited. Here is an overview of each drive and their turning radius:
The FWD is easy to swing around a corner however the user should pay attention as the rear wheels will swing out in the opposite direction.
The MWD is easy to navigate around a corner however both the front and rear wheels will swing out too.
The RWD is hard to navigate around a corner (because of the large turning radius) and may take a couple of 3-point turns to get around the corner.
As you can see, the largest power wheelchair turning radius is the rear-wheel drive, with the forward and mid-wheel drives being around the same. Source: Karma Medical
Mid-Wheel drive power wheelchair
Mid-wheel drive power wheelchair is the most intuitive of the three. Because the powered wheels are in the middle, it is most akin to the body’s axis, so turning and navigating the wheelchair comes more naturally. The stability of 6 wheels means that driving over obstacles or slopes is safer and more comfortable and therefore suitable for both indoor and outdoor use. Of the three drive wheel configurations, the mid-wheel drive has the smallest turning radius and therefore the easiest to navigate for new users.
Rear-Wheel drive power wheelchair
Rear-wheel drive power wheelchair is most suited for outdoor and long-distance use. The rear wheels offer good overall suspension, especially over rough terrains. The larger turning radius means that it will take the user longer to learn to drive however if the user has driven a car then the rear wheel drive can be more intuitive.
To further help demonstrate the impact of a small or large turning radius, take a look at how each wheel configurations will turn a tight corner:
The chassis that the user chooses will ultimately depend on their lifestyle. Is the user going to be predominantly outdoors? Do they need a power wheelchair to commute to work? Will they be going in and out of buildings often? These are all questions that the user needs to consider when choosing a power wheelchair.