Wheelchair users have been increasing in Japan recently due to the advance of the aging society. To reduce load on the attendant, power-assisted wheelchairs can be used. For safe and comfortable design of such wheelchairs, the attendant's work load needs to be predicted and estimated. We investigated the force needed to propel the wheelchair load based on the road resistance using a newly developed treadmill to analyze and obtain the suitable propelling motion. We tried to model the main movement in an attendant and wheelchair system. A power-assist system using the model reference adaptive control was based on the self-directive propelling force against the load in this model. We verified the driving performance and effect. The exercising heart ratio was used to show the movement strength for the walking velocity and pushing force and to evaluate the power-assist mechanism that we propose.
