Abstract
In this study, changes of the pressure distribution of a chair used at work was measured with a pressure measurement system. The pressure distribution was divided into three sections: the large thigh, the buttock, and the dorsal section, and each section was changed into a power-spectrum of a time series. We compared the inclination of the recurrence of the straight line of the power spectrum and the frequency with ‘1/f Swinging’ which shows the degree of comfortableness. The subjects are 8 university students. They performed word-processing input work for 45 minutes, after which, they subjectively evaluated the chair. We measured the pressure distribution at every second. The results were as follows: The pressure distribution showed a changed random time series pattern. Therefore, a static evaluation index is unreliable; and the recurrence analysis was done between the each power spectrum and the frequency. We compared the regression line with ‘1/f Swinging’. Concerning the large thigh and the buttock, the correlation coefficient between the subjective evaluation and the variable coefficient of the regression line was low. However, we obtained an extremely high correlation between the regression line and the subjective evaluation for the dorsal section.
