Velocity and orientation control in an electrical wheelchair on an inclined and slippery surface

Abstract

People with disability increase everyday due to accidents, poor health care and aging of the population. While some of these disabled people are strong enough and can comfortably use manual wheelchairs to move, others are too weak and may find it extremely difficult to drive powered wheelchairs with basic functionalities. Wheelchairs adaptable to various specialized functionalities may therefore be important if mobility of the severely disabled persons is to be ensured. Control parameters adaptable to hand, tongue or even head joysticks may consequently be necessary. Authors of this paper considered linear velocity and angular position for control. With such control parameters the wheelchair user may navigate and reach every desired location. To mimic real outdoor situations, slippery, inclined and flat surfaces are also considered. The dynamic modelling procedure used in this paper is based on the Euler–Lagrange formalism. The wheelchair platform considered in this paper is a differential drive platform with two passive front caster wheels and two active rear wheels.