Development and evaluation of a low-cost passive wearable exoskeleton system for improving safety and health performance of construction workers: A pilot study

Construction workers have an increased risk of having muscle fatigue and musculoskeletal injuries, among other non-fatal workplace injuries. As a result, this project aimed to develop and evaluate a low-cost passive wearable exoskeleton system for improving construction workers' safety and health performance, mainly by mitigating the risk of developing musculoskeletal pain and fatigue. Surface electromyography (sEMG) was used to evaluate muscle activity in the Thoracic Erector Spinae (TES) and Lumbar Erector Spinae (LES) at the L3 and T12 vertebrae level, respectively, during repetitive handling tasks. In addition, both subjective (e.g., rating of the fatigue scale) and objective fatigue indicators (e.g., heart rate, skin temperature) were employed to assess fatigue. Exoskeleton use was associated with a 30% decrease in LES muscle activation compared to baseline. The application of an exoskeleton had a similar effect on the TES, decreasing muscle activity by 12%. When using an exoskeleton, a participant's neck kinematics were reduced by 23%, their low back kinematics by 11%, their hip kinematics by 5%, and their knee kinematics by 36%. Exoskeleton use was associated with a 13% decrease in heart rate and a 67% decrease in perceived fatigue. Nonetheless, skin temperature was raised by around 2% while using an exoskeleton compared to when not using one. Our preliminary findings suggest that the passive exoskeleton system could be an effective ergonomic intervention tool for assisting construction workers engaged in manual repetitive handling activities.