About ride comfort due to differences in running speed of manual attendant-controlled wheelchairs

Abstract

One of the problems with wheelchairs is that the vibrations generated during driving can cause users to experience motion sickness, discomfort, and annoyance. Wheelchair tire pressure is considered to be one of the factors that affects the ride comfort of a wheelchair. However, it is not yet known how much influence the tire pressure of a wheelchair has. One of the reasons for this is that it is not possible to accurately measure tire pressure with the English valve used in wheelchairs. Therefore, we created a tire pressure indicator to accurately measure the tire pressure of wheelchairs. The purpose of this study is to use the tire pressure display to evaluate the impact of changes in tire pressure on assistive wheelchairs on vibration. In addition, in this experiment, we created a device to push the assistive wheelchair using an electric wheelchair in order to make the assistive wheelchair move at a constant speed, aiming to improve the reliability of the data. In this paper, we examined the effects of different running speeds on ride comfort.In this study, we use a triaxial accelerometer to measure the vibration of the tire pressure of a manual attendant-controlled wheelchair in four patterns: 80kPa, 160kPa, 240kPa, and 320kPa. This measurement is performed at three different running speeds: low speed, medium speed, and high speed. FFT analysis is performed on the acceleration in three directions measured by the triaxial accelerometer, and the maximum power spectrum, frequency and integral value at the maximum power spectrum are determined. From these values, evaluate the trends caused by changes in tire air pressure. Verify the relationship with tire pressure. Riding comfort was evaluated using the SD method, and two types of evaluation were performed: stationary and running. The evaluation items consisted of three items, sitting comfort, sense of security, and sitting comfort of the buttocks, for both static and running conditions, and four items, including the strength of shaking while running. Responses were obtained on a five-point scale from 1 to 5. In this study, we verified the results of vibration measurements and sensory evaluations, and verified ride comfort due to differences in driving speed and tire air pressure.

Keywords: Wheelchairs, Ride Comfort, Running Speed, Vibration, Tire Air Pressure

DOI: 10.54941/ahfe1004616