Wheelchairs: material, mechanical work and vibration
The vibrations experienced by the whole-body during wheelchair affect both comfort and safety. The vibrations from folding wheelchairs can be either anteroposterior (forward and back), caused majoritively during self induced acceleration and deceleration. Side to side (mediolateral) vibrations are generally negligible. The floor surfacing also has an effect on vibrations, with smooth vinyl giving minimal overall vibrations. Textured mats and obstacles result in vertical vibrations (up and down).
A wheelchair that transmits fewer vibrations requires more mechanical work, therefore more energy input. The material used to construct the chair is also of significance as carbon in wheelchair construction shows promise in decreasing vibration without increasing workload. Interestingly titanium does not show benefit over use of aluminum in this area.
To qualify these statements further research must reproduce the outcomes with a wider range of materials for the chairs.
> From: Chénier et al., BioMed Res Int 2014 (2014) . All rights reserved to The Author(s). Click here for the Pubmed summary.