The rolling resistance of wheelchairs

The performance of racing wheelchairs as mechanical systems has been examined. The factors contributing to the rolling resistance of the wheelchair: internal resistance, tyres, surface type, wheel alignment and system mass, were all considered. Significant increases in rolling resistance have previously been reported for small misalignments of the rear wheels at rates below racing speeds. A tool was developed that allows the alignment of the rear wheels to be measured simply and accurate to 0.2°. A system to allow the direct measurement of rolling resistance was constructed and measurements were taken over a wide range of cambers, misalignments and speeds. It was found that rolling resistance increased to 3 N at 6 ms-1 and that wheel misalignment produced the highest rolling resistance particularly at low speeds.