Frederick L J, Armstrong T J
Department of Safety and Environmental Management, West Virginia University, Morgantown 26506-6070, USA.
Ergonomics. 1995 Dec;38(12):2447-54. doi: 10.1080/00140139508925278.
The effect of friction and load on pinch force was studied in a simple hand transfer task using a repeated measures design and ten men. Subjects moved a container between two targets, 450 mm apart, at a slow, self-paced speed. The levels of mass in the container were set at 0.8, 2.5 and 4.2 kg (7.5, 24.5 and 41.5 N respectively). The handle materials were sandpaper and smooth aluminum. Applied pinch force was measured via a strain gauge mounted in a specially-designed handle attached to the container. Dependent variables were peak and 'steady-state' pinch force. The main and interaction effects of load and friction were significant. The friction effect was significant only for the highest load which, on average, elicited peak pinch forces of 16-70% of maximum voluntary force. This suggests that these men were not sensitive to friction effects at the lower loads. Results suggest that the use of tool handle friction enhancements may reduce required pinch forces for objects requiring upwards of 50% or more of maximum pinch strength.
在一项简单的手部转移任务中，采用重复测量设计并招募了10名男性，研究了摩擦力和负载对手捏力的影响。受试者以缓慢的、自我设定的速度在两个相距450毫米的目标之间移动一个容器。容器中的质量水平设定为0.8、2.5和4.2千克（分别为7.5、24.5和41.5牛）。手柄材料为砂纸和光滑铝。通过安装在连接到容器的特殊设计手柄中的应变仪测量施加的手捏力。因变量是峰值和“稳态”手捏力。负载和摩擦力的主效应和交互效应显著。摩擦力效应仅在最高负载时显著，平均而言，该负载引起的峰值手捏力为最大随意力的16%至70%。这表明这些男性在较低负载下对摩擦效应不敏感。结果表明，对于需要超过最大捏力强度50%或更多的物体，使用增加工具手柄摩擦力的方法可能会降低所需的手捏力。
