Reto Togni, Laboratory for Movement Biomechanics, ETH Zürich
Stefan Villiger, Laboratory for Movement Biomechanics, ETH Zürich
In manual wheelchairs, every change or adjustment of direction is associated with one-handed braking which results in energy loss and the need for re-acceleration. Directional control therefore significantly contributes to the physiological energy cost of wheelchair propulsion, is hazardous to users’ health and has been described as frustrating. With “steering-by-leaning”, we aim to remove these adverse conditions. With such a system engaged, the orientation of the front wheels and hence of the direction of travel is controlled by a laterally tilting backrest and users are allowed to steer wheelchair movement by leaning into curves. Equally, straightforward movement is maintained by sitting upright, also when moving along tilted surfaces such as pavements where conventional wheelchairs tend to veer off. The results are improved energy efficiency and easy one-handed propulsion, all while offering intuitive motion control to wheelchair users across a surprisingly broad functional spectrum.