Development of Power Add-on Unit with Sensorless Force Estimation and Slope-assistance System

Abstract

In recent years, the aging population has become a serious solid problem in developed countries. Whereas the number of caregivers is decreasing gradually, and the care burden is increasing. In this study, a novel power add-on driving unit (PAU) is developed for the reduction of the caregiver’s care burden. The PAU can be attached to or detached from the manual wheelchair easily. This PAU is very practical and has merits in cost, portability, compatibility and so on. Since the PAU is propelled by the caregiver, a novel control method is necessary for the ease of use. In this paper, a force sensorless observer is proposed, and the burden of wheelchair running on the slope is analyzed from kinematics. Finally, the effectiveness of our proposed burden reduction method is verified by the experiments.