Design of a rugged wheel for application in the Leveraged Freedom Chair

Abstract

This thesis analyses the front wheel of the Leveraged Freedom Chair (LFC) an all-terrain, off-road wheelchair with two distinct models: one for the developing world and one specifically for American riders. The functional requirements of performance and price, were designated by the start-up company Global Research Innovation and Technology (GRIT), which makes the LFC. This study includes comparisons between the original rubber wheel, which is currently being used as the front wheel of the LFC, and alternative wheels available for purchase. The goal was to find a new wheel which could be implemented for future manufacturing to increase the lifespan of the LFC, improve the ride quality and efficiency of production. Based on performance it is concluded that a pneumatic wheel of comparable geometry to the original rubber wheel is the best alternative for the American chair where maintenance is more routine and replacement parts and service are readily available. For the developing world future work is necessary to either improve the quality of the original rubber wheel or select a low cost, low maintenance alternative.