A Basic Study on Measurement of Stroke Information Using an InertialSensor for Evaluation of Upper Limb Movements during Wheelchair Propulsion
Wheelchairs are widely used as assistive devices to aid ADL for paraplegic people. However, overuse of upper extremities frequently leads to shoulder pain and carpal tunnel syndrome. The purpose of this study was to evaluate upper limb movements during wheelchair propulsion using an inertial sensor. In this study, coordinate values of the vector defined on the upper arm were calculated from an inertial sensor attached on the upper arm. Methods of detecting stroke motion and for measuring the push cycle by using this vector were examined. Ten able bodied (i.e. non-wheelchair users) propelled the wheelchair on 10m long level and sloped surfaces. Excluding the first stroke and the braking motions, detection rate of the stroke number was more than 97% and mean absolute error of the push cycle was less than 30ms on both surfaces. The results suggest inertial sensors can be used to measure wheelchair activity accurately and reliably.