A biomechanical and psychophysical examination of fastener initiations in automotive assembly

The purpose of the current study was to determine acceptable human tolerance limits for a fastener initiation task, which is commonly performed in the automotive industry. A biomechanical and psychophysical methodology was utilized to examine 24 non-skilled female subjects while performing fastener initiation tasks on a simulation device. Three wrist postures (neutral, flexion and extension) in combination with two fastener sizes (large: 10 mm in depth and 20 mm in diameter; small: 5 mm in depth and 10 mm in diameter) were the conditions examined. Fastener initiations per minute, duration of each fastener initiation and the quantity of efforts (individual fastener rotations that comprise each Fastener Initiation) within each fastener initiation were the kinematic measures. Electromyography was also employed to provide data from the muscular activity of the forearm and hands while performing the task. Repeated measures ANOVA with Tukey's significance post hoc test were used to determine any significance within the measured variables (p < 0.05).; This study has provided recommendations on acceptable human tolerances for the task of fastener initiations used in the manufacturing industry. (Abstract shortened by UMI.)...