A framework for evaluating muscle activity during repetitive manual material handling in construction manufacturing

Workers in construction sites are exposed to highly labor-intensive tasks. Ergonomic principles, in addition to engineering considerations, should thus be included in the design of workstations in order to minimize the risk of injury. The objective of this paper is to propose a framework to assess muscle force and muscle fatigue development due to manual lifting tasks using surface electromyography (sEMG) and human body modelling. Muscle forces are calculated using the human body model and compared qualitatively to sEMG muscle activities. The results show that sEMG is capable of visualizing muscle activity. However, sEMG application in identifying muscle fatigue development is limited to bulkier and superficial muscle bundles in low fat areas. The proposed human body model, which is driven by kinematic motion capture data, predicts muscle forces during the entire task maneuver. The predicted muscle forces from the human body model are compared with sEMG data from corresponding muscles as well as data available in the literature. In future research, the developed model will be used to determine optimal task maneuvers that minimize muscle forces with the ultimate goal of preventing muscle injuries in workstations.