Date of Award


Publication Type

Master Thesis

Degree Name




First Advisor

Joel Cort


Automotive manufacturing, Ergonomics, Force measurement method, Ground reaction forces, Hand force exertion, Work-related musculoskeletal disorders




The purpose of this study was to determine the strength of the relationship between the ground reaction forces (GRF), forces directly recorded at the feet and the force exerted by the hands as measured at the hands, during simulated work-related tasks, in an effort to understand the validity of GRF measurements as an accurate alternative indirect measurement of physical hand efforts. Thirty healthy participants were recruited between the ages of 18-60 years with no history of pain or injury in their upper and lower extremities for the previous six months. A total of seven manual hand exertion tasks were simulated and their associated force efforts were obtained. Six of the seven task efforts was completed with and without the ability of the participants to brace themselves while the last task was only completed without a brace. The brace is an external object that was placed between the participant and the vertical force plate. Root Mean Squared Error (RMSE) was calculated to find the percentage error between forces recorded at the hands and the forces measured at the feet. Results revealed that without Brace tasks often resulted with a significantly lower RMSE compared to Bracing tasks, the Drilling task was found to have the smallest RMSE while the Electrical Connector task showed the highest RMSE, and an increase in RMSE was evident with tasks requiring repetitive/wiggly movements (Hose and Weather-Strip tasks).