Investigation of the Assist Effect Evaluation Method Using Fingertip Plethysmogram

Abstract

Many workers suffer from low back pain. As a countermeasure, we have developed and sold a muscle suit series for waist support. In 2019, we launched a mass-produced model called “Every” that reduced the price from 500,000 yen or more to 100,000 yen and have shipped more than 20,000 units to date. The global market for power assist suits is estimated to be about 158,600 units, and it is expected to expand at an annual growth rate (CAGR) of approximately 17.1%. On the other hand, there is still no unified evaluation metric for the assistive effects of the devices, and the current situation is that each company uses its own indicators to express the assistive effects. Therefore, in this study, we focused on fatigue during work as an evaluation metric for assistive effects and attempted a quantitative expression using fingertip plethysmogram.