Previous attempts at stair-climbing wheelchairs have posed additional problems, even if they managed to help wheelchair users navigate staircases. The details of wheelchair design are extremely important, and any change in dimensions or ease of use could make the wheelchair impractical for a slew of reasons other than staircase inaccessibility. Scalevo is the first stair-climbing wheelchair to stick close to the size of traditional manual wheelchairs, specifically designed to fit through standard door spaces and maneuver indoors without added obstacles or hassle.
Scalevo also doesn’t require a huge amount of upper body function or arm strength, which were issues with previous stair-climbing wheelchair releases. The parallel rubber tracks mounted to the bottom of the wheelchair are activated from a button in the wheelchair’s armrest, or even resting in the lap. The tracks adjust with the angle of the seat of the chair so that as Scalevo climbs, the person seated is always upright and comfortable. Scalevo can also climb spiral staircases, steep angles, and steps made of any material, according to Miro Voellmy of the ETH Zurich team.
Thanks to the incline of the chair while the rubber tracks cover the distance over steps, a Scalevo user won’t feel the bump of every step in a jostling ride. The rubber tracks make use of a large, sturdy footprint to keep the chair from tilting or losing balance, and to facilitate a smooth ride that feels more like a ramp. Functions like these will be put to the test when Scalevo competes in the 2016 Cybathlon, an ETH Zurich challenge event for pilots with disabilities — a competition which features cutting edge assistance devices, often developed by ETH student teams.
When not in use on a staircase, Scalevo’s flat ground function works much like the balance system of a Segway. Two main wheels keep the chair in balance and allow for the user’s complete control over direction, including turning on the spot the same way a Segway might. The Scalevo team also believes that once completed for production, the wheelchair will be available on the market for a price only marginally more expensive than traditional wheelchairs.