Input device for electric wheelchairs considering physical functions of persons with severe Duchenne muscular dystrophy

Abstract

Persons with severe Duchenne muscular dystrophy (DMD) cannot operate electric wheelchairs through standard joysticks because they lack muscular power and are affected by deformation of the hands. To address this difficulty, first the authors determined the requirements of input devices based on a survey of the daily life of persons with DMD and the authors developed new joysticks for an electric wheelchair considering the characteristics of the hand functions of persons with DMD. These devices were based on a quantitative evaluation of the hand functions of persons with severe DMD, which consists of fingertip force and range of motion of the fingers. Two new joysticks were developed, considering hand function, posture, and hand shape of two persons with severe DMD. Thus, the devices can be operated using slight force and movement of the fingers. Furthermore, the authors examined the shape of the hands of persons with severe DMD to determine the shape of the devices.