Abstract
This study aims to formulate a relationship between total perceived discomfort (TPD) and six joint moments { shoulder, elbow, L5/S1, hip, knee, and ankle. We conducted a manual material handling experiment with varying holding points and load amplitudes and measured joint angles and subjective TPD. Furthermore,joint moments were calculated from the measured joint angles. Three approximation models { sum, maximum,and square sum { were compared in terms of TPD prediction accuracy, and the sum model was selected as the TPD function because its average error was lowest. Individually approximated TPD functions for males and females did not show improved accuracy compared with the TPD function for both genders. Therefore,a single TPD function was applied irrespective of gender. The correlation coefficient between measured and predicted TPD functions was compared to those of four observational methods { OWAS, RULA, REBA, and NIOSH lifting equation; that of the proposed TPD function was the highest.
