Assessing fall risk in construction: Effects of a passive back support exoskeleton during slip and trip perturbations

Passive back support exoskeletons (BSEs) have been recommended to reduce the incidence of work-related musculoskeletal disorders and to improve productivity in the construction industry. The biomechanical indicators of fall risk (e.g., slips and trips) associated with BSE use during construction tasks, such as walking and load carriage, have not been fully investigated. This study aimed to evaluate these indicators while workers carried an object while wearing a BSE. Simulated slips and trips were introduced while participants walked on an instrumented treadmill with and without carrying an object. Three conditions were created: without BSE (WOE), with BSE “OFF” (EOF), and with BSE “ON” (EON). Ground reaction forces (GRF), activation of trunk, hip, and thigh muscles, and hip joint angles were measured using force plates, EMG, and a motion capture system. BSE use in both modes significantly altered a few GRFs, muscle activations, and hip joint angles. The changes were more pronounced when participants carried an object. Notably, EON increased lateral GRF by nearly 25% after slip perturbation. It also reduced the peak angle of hip adduction by almost 52%. Additionally, hip abductor activation increased by nearly 15%. These changes indicate a less effective reactive response. The study explores the reasons for changes and their practical implications, emphasizing the need for design modifications in BSEs, user training, and guidelines for BSE usage at construction sites. The findings help construction stakeholders make informed decisions about BSE adoption and guide manufacturers in developing better BSEs for walking and carrying tasks.