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The manoeuvrability of a wheelchair is dependent upon a variety of mechanical and personal factors. Your weight and the design of your wheelchair are two of the most important aspects of your mobility, heavily affecting your wheelchair’s speed and manoeuvrability. For instance, a wheelchair’s resistance and bearing are influenced by the friction between the wheel and ground.
Another important feature that affects a person’s mobility is the biomechanics of the wheelchair and user. To optimise biomechanical factors, you’ll have to account for the effects of your weight and body shape upon the position and size of the wheels, angle of the wheelchair’s axles and the distance between the front and rear axles. By considering these different factors, you’ll be far more equipped when it comes to choosing your wheelchair and successfully overcoming any mobility problems.
The Importance of Choosing the Best Wheelchair
When moving in a wheelchair, it’s imperative that the user has maximum mobility, comfort and functionality. Badly fitted or cheaply constructed wheelchairs can result in a range of issues, including slipping, poor posture and long term discomfort. Therefore, when choosing a wheelchair, you should always be mindful of the wheelchair’s design and whether it suits your physical requirements.
Major wheelchair companies, including Sunrise Medical, offer a wide range of adjustable and active wheelchair models. By using a well fitted and well-designed wheelchair, you can travel in a far more comfortable and mobile fashion.
There are four factors that everyone should take into account when considering the mobility of a wheelchair: weight distribution between the wheels, where the centre of gravity is located, the surface you’ll be using the wheelchair on and the wheelchair’s design specifics (for example: material, size, type of wheel).
1. Front and rear wheel weight distribution
A wheelchair’s weight distribution is calculated by determining how much weight is supported by the front wheels in comparison to the rear wheels. Having a greater amount of weight distributed between the front wheels magnifies the effects of friction, meaning you’ll have greater stability but you’ll also have to exert more energy to move the wheelchair.
One of the most traditional weight distributions in wheelchairs is 50% on the front wheels and 50% on the rear wheels. This design is commonly used in geriatric wheelchairs as the relatively high proportion of weight on the front wheels significantly increases stability.
Moreover, as most geriatric wheelchairs are not self-propelled, the increased effort to move the wheelchair can be easily offset by motorised systems. In comparison, a 20% front-wheel distribution and 80% rear-wheel distribution will guarantee greater mobility at the cost of reduced stability. Therefore, this configuration is only recommended for users that have adequate upper body strength.
2. Adjusting for the centre of gravity
Changing your wheelchair’s centre of gravity is one of the most important adjustments you can make. The centre of gravity is the point where your wheelchair’s weight is evenly balanced and its placement has a substantial influence on your mobility and stability.
Most aluminium wheelchairs have a variety of axle configurations, allowing you to fine-tune and adjust your wheelchair’s centre of gravity. The further you adjust your centre of gravity backwards and upwards, the greater the rear-wheel weight distribution. As discussed, this leads to increased mobility but reduced stability. Most modern wheelchairs include a lever and axle plate system that can be used to easily adjust your centre of gravity and thus, your mobility.
3. The terrain that the wheelchair will be used on
Your wheelchair’s manoeuvrability and speed will be heavily influenced by the surfaces and type of terrain you plan to use it on. If you will be spending most of your time indoors or intend to play sports, it’s a good idea to get a wheelchair with smaller front wheels as you’ll be able to perform quicker turns. However, if you are often travelling outside or planning to use your wheelchair on rough surfaces, it’s better to use larger front wheels. This gives the wheelchair more contact with the ground, helping you move across rougher sections of terrain.
4. The wheelchair’s biomechanical factors
The material, size and design of a wheelchair’s wheel system are some of the most important factors affecting your wheelchair’s mobility. Your choice of wheel material, whether it’s solid or pneumatic (air filled), will depend on your mobility requirements.
While pneumatic wheels create increased friction between the wheel and ground, they also offer greater comfort and give you the option of adding shock absorbers. In comparison, solid wheels improve your wheelchair’s mobility but are unable to adapt to hardening or softening terrain. In terms of sizing, as your wheelchair’s wheels get smaller, you will see a proportional decrease in the wheelchair’s traction (friction between ground and wheel) and a corresponding loss in each wheel’s grip on the ground.
Your choice of wheel material and size should also be influenced by the terrain you intend to use your wheelchair on. Softer surfaces increase friction, meaning that you’ll need more momentum to move your wheelchair.
Another critical aspect of your wheelchair’s mobility and stability is the distance between wheels, also known as the wheelbase. Smaller wheelbases result in improved turning and overall manoeuvrability.
Were you already aware of the importance of these factors in wheelchair design? Has this information helped you decide on a personalised wheelchair? Choosing an adjustable and active wheelchair will facilitate greater mobility and provide you with increased comfort, independence and general wellbeing.
Sunrise Medical offers a huge range of manual wheelchairs and powered wheelchairs, helping you choose a model and design that perfectly suits your needs. Contact us to receive personalised guidance and information from one of our highly trained staff members.