荷物運搬作業における取り扱い物の重さと作業後の重さ感覚の関係

抄録

In this study, we attempted to analyze how the sense of weight changes after handling a material. Ten healthy male subjects were provided with 2 kg of a certain material as a reference so that they could sense and memorize its weight. Next, they were asked to move three buckets with different weights (1, 3, and 5 kg) to predefined right and left hand side positions and to select the bucket that they felt had the same weight as that of the reference material from among nine buckets with different weights ranging from 1.6 to 2.4 kg in intervals of 0.1 kg. Further, we analyzed the influence of the subjective weight of the material being handled, amount of muscle activity, and fatigue experienced by biceps brachii muscles on the sense of weight. The results indicate that subjects feel the weight to be greater than it is when moving the 1 and 3 kg buckets. On the other hand, subjects feel the weight to be lesser than it is when moving the 5 kg bucket. This study suggests that the sensed weight decreases with an increase in the weight of the moved bucket.