Abstract
This research was done to clarify the meaning and the essential features of the HIC. At first, it is shown that as the order of the exponent in the equation of HIC is higher, the selected time interval becomes narrow, and the role of the exponent of 2.5 is a way to select the main peak from the noise. Next the data of the experiments using Articulated Total Body in JARI is shown, and the obtained actual accelerations are shown well fitted by Gauss function. Gauss fitting is well applied for almost all cases. Next we derived a simple formula to calculate the HIC based on Gauss function. As a result, HIC are expressed by only two parameters, i.e., amplitude A and distribution (sigma). The results will be important for the future works of the analysis based on the HIC. We show that the HIC strongly depends on the sharpness of the peak. The sharpness is determined by floor condition and protectors for head and body. It is concluded that helmet is very useful since it makes a long duration in collision, then it makes HIC lower than that without a helmet.
