Efficiency and Rolling Resistance in Manual Wheelchair Propulsion

The efficiency and the rolling resistance in wheelchair propulsion play an important role in the comfort and the health of wheelchair users in daily life. Here we identify these fundamental interactions of wheelchair-user system on treadmill and on track. We measured the oxygen uptake (input) and the propelling torque (output) as the parameters with velocity and tire pressure. The efficiency increased about 9-13% as the velocity increased on treadmill and it increased around 11-12% as the tire pressure reduced on track. The mean coefficient of rolling resistance was 0.012 on treadmill and that were 0.016 (200 kPa) and 0.026 (30 kPa) on track. Our experimental results indicated that the efficiency and the rolling resistance were strongly dependent on the velocity and tire pressure.