Mowing Patterns Comparison: Analyzing the Mowing Behaviors of Elderly Adults on an Inclined Plane via a Motion Capture Device

Due to the declining population and the aging of the farmer population in the hilly and mountainous areas of Japan, it is necessary for the elderly to carry out the mowing work on the ridges and slopes, which is traditionally regarded as heavy labor as part of paddy farming. One of the most important causes of these accidents is an incorrect mowing posture; therefore, it is important and necessary to identify effective and safe working patterns during inclined plane mowing. In this paper, we designed and implemented a set of mowing experiments in a terraced field area in Hiroshima to collect information on the body motion of experienced elderly mowing workers via a high-precision motion capture device that supports the collection of information from 23 joints. According to an analysis that calculated the angles of the workers' joints during mowing, we confirmed the characteristics of the mowing workers' working patterns in three different situations (typical inclined plane mowing (TI), top-down mowing (TD) and bottom-up mowing (BU)). The comparative analysis indicates that the basic actions “c” (cutting) and “t” (throwing) are basically the same in terms of body posture for the situation TI, but for situation TD, the difference was observed with respect to the workers' right ankle. Moreover, based on the comparation analysis for mowing action “c” (cutting), we confirmed that mowing workers should: keep their lower bodies as still as possible to keep balance for ensuring safety while working on inclined plane (TI); keep careful even if they are working on the flat ground (TD); and do not exert their utmost strength to mow, unless they are standing on the flat ground (BU). The findings of this work should be emphasized in the future development of mowing support systems and training programs for new mowing workers.