Fluctuation analysis of finger plethysmograms related to various conditions

This study developed an analytical method for estimating and presenting the rating of perceived exertion (RPE) by using fluctuation analysis of largest Lyapunov exponent and heart rate variability. The method was applied to method to analyze a series of experiments conducted in various conditions including the use of a variety of driving seats to observing exertion and fatigue processes during a longer sitting a seat. We described the generating rate of and driving cause of the fatigue processes, respectively, by differentiation and acceleration of the RPE relations. We further explored the acceleration by wavelet analysis and found characterizing categories in relation to individuals and conditions.