Reinventing the Wheel(chair)
It’s every designer’s dream: to actually reinvent the wheel. Though usually a pipedream, there are a few cases in which the wheel gets a real makeover. Perhaps this is one of those times.
Faced with a debilitating injury, an Israeli farmer-turned-designer was frustrated at the clunky ride of the wheelchair he was bound to. Literally feeling the need for a softer ride on his wheelchair, he started experimenting.
The new wheel is a three-spoke design, by start-up SoftWheel. Each of the spokes is a hydraulic shock-absorber, and this is the innovation. By replacing normal spokes with these compression cylinders, the wheel and its suspension are combined.
When the chair hits an obstacle, the wheel hub moves to absorb the impact, allowing the chair to ‘float’ over a bump. Residual forces are absorbed by the wheel structure, which is essentially a dynamic compression disc.
That’s why the whole wheel is made from one material – high-strength and light-weight steel. The weight is crucial, particularly for self-propelling wheelchair users, who have no desire to push around more weight than absolutely necessary.
According to SoftWheel, up to 30% of the energy expended is lost because wheelchairs generally lack suspension. That means only 70% can be used for propulsion, which is inefficient and uncomfortable. In the case of the SoftWheel, a mechanical threshold is set so that the wheel only becomes responsive after a certain level of force acts upon it.
As with much great design, it’s not so much about an entirely from-scratch idea. The SoftWheel is more like a clever arrangement of existing parts. This allowed the inventor to apply the principle to bicycles too.
In as little as 10 minutes, factory produced bicycles can be fitted with the SoftWheel. This has naturally led to interest from other industries. The technology is expected to find its way into cars (Daimler has already expressed interest) and possibly aircraft too.