Psychophysically Based Physical Capability Limits For Right Angle Power Tool Operation

Abstract

A psychophysical methodology was utilized to examine 40 non-skilled female participants performing right-angle power tool (RAPT) fastening tasks. A combination of two between subject variables were examined for a total of four between-subject groups: joint orientation (horizontal and vertical planes) and joint hardness (hard and soft joints). Participants were evenly distributed into one of four joint orientation- hardness groups. Within each group, a combination of three fastening strategies and three fastening frequencies were performed by each participant. The chosen target torque determined the physical capability limits (PCL). A mixed-design repeated analysis of variance with Tukey’ significance post hoc test were used to determine any significance with the measured variables ( p<0.05). Fastening strategy and frequency influenced the chosen torque magnitude. Participants chose significantly higher target torques with the Turbo Tight strategy in comparison to the other two strategies. Furthermore, participants chose to accept lower target torques and forces as fastening frequency increased.