Design and Analysis of a Stair Climbing Wheel Chair

Abstract

This paper aims to bring forward a means to climb stairs easily for older and disabled people. A stair climbing wheel chair machine, a semi-automated vehicle, which has the capability to climb the stairs easily. a wheel chair is designed and analyzed with planetary gear system attachment for the wheels. The structure and assembly of planetary wheel basic parameters required have been calculated for climbing steps without slipping. The stress analysis on wheel chair has been performed for its various operating conditions. When the wheelchair climbs stairs, there is danger of falling down the stairs, hence in order to protect the user to avoid this kind of situation to happen a ratchet mechanism locking system is proposed. Most wheelchairs are oblique during the process of climbing up and down stairs and the user will feel uncomfortable as it can easily turnover, which poses a big safety risk. In order to overcome this problem, a seat backrest adjusting device is proposed for this wheelchair, so before the wheelchair climbs up and down stairs, this device will adjust an angle for the seat and backrest to make sure the seat of the wheelchair keeps level with the ground all the time. The wheel chair assembly is modeled and its components are analyzed by considering three different materials under various likely possible loading conditions on wheel chair with the help of finite element analysis software and the results are presented.