The handle of a commercial bar clamp was redesigned using ergonomic principles and then compared with an original clamp. Ten
male and ten female students participated in simulated clamping tasks under various conditions, including different clamping
heights, clamping methods, and handle-gripping methods, with respect to the dependent variables of clamping and handle-squeezing
forces. The results showed that the redesigned clamp produced larger clamping force with lower handle-squeezing forces than the
original clamp. As expected, males exerted more force than females in both clamping and squeezing forces. A pistol grip method was
superior to an upside-down handle-gripping method. Two-handed operation was recommended for this type of clamp by
simultaneously pulling the trigger and sliding the bar in order to initially tighten around objects. This study shows that the
application of ergonomic guidelines increases the efficiency and usability of manual handtools.
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