Pulse wave measurement system by rPPG from multiple human sites by including the sole

In this study, we explored non-contact pulse wave measurements from the extremities, particularly the soles, and examined their differences. Two experiments were conducted. First, we identified the optimal method for capturing pulse waves and discovered that the peak intensity of the green signal was the most effective. Then, we analyzed the temporal deviations between the electrocardiogram (ECG) and extremities based on these findings. Differences were observed in the face, palms, and soles of the feet in observing only three subjects. Previous attempts at extremity measurements have been made; however, our study is the first to focus on the foot sole. This study will pave the way for broader medical and research applications.