THE EFFECT OF SEAT AND BACKREST CUSHIONS ON THE VIBRATION AT THE CHEST FOR TWO PHYSIQUES

Abstract

The aim of this study was to clarify the basic relationship between the physique of subjects who sat in an experimental seat and the effect of cushions installed on the seat. The experimental seat was vibrated perpendicularly so that the subject could experience the same vibrational conditions as he/she would experience when riding in a car on an actual road. The cushions were rectangular parallelepiped in shape, so that the effect of the shape but not the thickness could be neglected in considering the basic relationship. The two male subjects selected for these experiments had different physiques: one had a large physique, while the other was thin. As a result, it was suggested that the cushions would increase the differences in the dynamical characteristics due to vibration between thin and solid-built subjects. The thin subject tended to be more affected by changes in the properties of the backrest than the large person.