Breakdown of An Electric Wheelchair
Wheels & Tires of All Kinds
All mobility vehicles are designed to operate optimally on flat, smooth surfaces. When it comes to unpaved or bumpy terrain, some power chairs fit the bill and some don’t. A crucial part of a mobility vehicles performance in these conditions depends on the type of wheels and tires it has.
Another factor differentiating tires and their performance is whether they are solid, air filled or chemical filled. One model alone may feature two or more wheel types - some power wheelchair have six wheels, and since each set has a different function, they often use different tires.
Choose what you’ll require for your needs:
Pneumatic Tires (air filled)
These tires have an outer and inner part, the inner tube is air-filled much like a bicycle tire. Usually, the two are purchased together so if you break one, you’ll also change the other at the same time.
The advantage of air filled tires is the ability to adjust the air pressure according to your needs. If you want shock absorbance at a far better level than any other tires, simply decrease the pressure and you’ll get a smoother ride. Conversely, for better performance and efficiency, increase the air pressure.
Pneumatic air tires do require some maintenance - air pressure levels need to be maintained, and a sharp object may give you a flat, but there is a very large range of sizes available making them attractive to many customers and manufacturers.
Solid Urethane Tires
Urethane tires are solid, so they’re maintenance free and take longer to wear out than other tires. Having solid urethane tires means a very minimal amount of maintenance will be necessary: no worrying about flat tires or punctures, and some designs are actually very easy to install.
A few off-road designs (with deep tread and wide grooves) have reportedly “chunked”, that is to say, small pieces of tire have broken away, but this is very uncommon.
More durable wheels are offered for usage on and off-road, and for other kinds of unpaved terrain. These usually have deep treads and wide grooves to provide more traction on surfaces such as loose dirt, mud, sand, or gravel. Certain models even offer special wheels that are resistant to ice, snow, and other inclement weather, for people coping with cold climates.
If you only plan on using your mobility vehicle on unpaved and smooth surfaces it's probably better to use regular ties for the best energy efficiency and performance.
Tubeless tires are new-generational anti-puncture tires that consist of one piece unlike pneumatic tires that have outer and inner parts. The air pressure in the tire forces and seals it against the wheel-rim so no air can escape.
Some tubeless tires are filled with a special sealant that ensures you don't get a flat even in the case of a hole in the tire.
Rear, Front and Mid-Wheel Drive Explained
The drive wheels of an electric wheelchair are those that are directly connected to the motor and propel the vehicle. Precisely where those wheels are positioned on the chair makes a very big difference to its performance.
There are three categories of drive-wheels: rear-wheel drive, mid-wheel drive, and front-wheel drive.
Each is ideal for a certain type of user and certain needs. Additionally, each drive-wheel type has its own driving and handling characteristics, turning radiuses, advantages and disadvantages.
Here’s an overview of the three different drive wheel types so you can take full advantage of any particular benefit you want, by selecting the suitable wheel drive for you.
The original drive type, rear-wheel drive power chairs are some of the most stable chairs on the market. This type of chair has the highest top speeds available but also the largest turning radius.
Note that with rear-wheel drive chairs, going up steep hills will cause the chair to lean back. That’s why all such chairs (designed to go uphill) have anti-tip tubes, preventing the chair from tipping backward.
In this type of power chair, the drive wheels are essentially under the rider, which keeps the vehicle’s center of gravity aligned with the center of the drive wheels.
With mid-wheel-drive power chairs, there is an equal amount of the chair in front of and behind the rider, making it very stable and ideal for maneuvering in smaller and tighter spaces.
Unlike front-wheel drive power chairs, this type of electric wheelchair is not ideal for varied, uneven terrain because obstructions could get stuck in the front or rear casters (solid wheels), suspending the drive wheels, meaning the drive wheels have no contact with the ground and are unable propel the chair.
In this type of electric wheelchair, the drive wheels are in front of the seat. A sturdy solution for uneven terrain and up and down hills, front-wheel drive chairs can easily climb over small obstacles.
Most of the chair is behind the rider with this type, so remaining aware of what is behind the vehicle is key. The overall speed of this drive type is slower because at higher speeds fishtailing becomes an issue. Another issue this wheel-drive would face at high speeds is forward jerking in the case of sudden braking.