Evaluation of upper limb load intensity based on biomechanical methods / 中华劳动卫生职业病杂志

ABSTRACT

Objective@#To establish a model for evaluating the upper limb load intensity of workers based on biomechanical methods, and to verify its effectiveness.@*Methods@#15 male volunteers participated in lifting test of 3 kinds of external force load in March 2015. Volunteers’ operating postures, forces, and subjective load intensities were collected. The biomechanical models of lifting operation were established with the input of operating postures and forces, and to output joint torque of shoulder, elbow and wrist. The simulation results were normalized by the maximum torque of each joint, and the relative joint torque was obtained. Then the upper limb load intensity evaluation model, which related with relative joint torque of shoulder, elbow and wrist, was established based on analytic hierarchy process. In order to validate the validity of the model, the assessment results of the model and the subjective load intensities of the volunteers were contrasted.@*Results@#The weight of shoulder joint (0.56) was larger than the weights of elbow and wrist (0.27 and 0.17) in the influence factors of the upper limb load. Pearson correlation analysis showed that the upper limb load intensities of the model were significantly correlated with the subjective load intensities of volunteers (r=0.863, P<0.05) . There was no significant difference between the two groups (t=0.105, P>0.05) .@*Conclusion@#The evaluation model of the upper limb load intensity based on biomechanical methods could be used for predicting and evaluating the upper limb load intensities of workers.