Evaluation of grip force exertions in dynamic manual work.
Proceedings of the Human Factors and Ergonomics Society 38th Annual Meeting, October 24-28, 1994, Nashville, Tennessee. Santa Monica, CA: Human Factors and Ergonomics Society, 1994 Nov; 38(Ind Erg):549-553
Grip force strengths were measured in subjects during the performance of one of two manual tasks and compared with predicted forces. Right handed male subjects performed one of two manual tasks: 15 subjects grasped and lifted a cylindrical handle from the right side of a circular platform to a receptacle on the left side of the platform; and 15 subjects grasped and pulled downward on a suspended handle. Grip forces varied throughout the work cycle with changes in the motion of the handle. Peak grip force values were seen at the initiation of handle movement, as predicted. Peak force levels exceeded mean levels by up to 104% for the transfer task and up to 114% for the assembly task however a significant decrease in the ratio of peak to mean force was seen with increased object weight/resistance. Although the patterns of the force/time curves were generally sinusoidal, they differed from those hypothesized. Despite these differences, the models were found to provide relatively close estimates of peak grip forces during task performance. The pattern of variation in grip force was similar between subjects performing the same task. The author concludes that it is possible to predict variations in grip force during dynamic work.
Task-performance; Work-performance; Body-mechanics; Musculoskeletal-system; Mathematical-models; Work-analysis; Physical-capacity
Issue of Publication
Proceedings of the Human Factors and Ergonomics Society 38th Annual Meeting, October 24-28, 1994, Nashville, Tennessee, People & Technology in Harmony