Design and musculoskeletal modelling of a back support exoskeleton (BSE) for child care workers

This paper presents the design and musculoskeletal modelling of a passive back-support exoskeleton (BSE) aimed at mitigating musculoskeletal strain among childcare workers, a sector associated with a high incidence of musculoskeletal injuries. The study conceptualizes a lightweight, unobtrusive BSE tailored for manual child-handling tasks, designed to be worn under standard work clothing. To achieve this, the study employs 3D CAD modelling, the OpenSim musculoskeletal modelling software, and a mobile phone-based inexpensive motion capture system. This approach enables the development of a cost-effective design process and simulation method, eliminating the need for expensive physical prototypes or laboratory setups. Upon incorporating the BSE design into the OpenSim workflow, the simulation experiments consistently observe reductions in both peak and mean forces exerted by the Erector Spinae muscles. These reductions range from 0.8% to 7.2% for peak forces and from 12.1% to 16.8/% for mean forces. The methodology employed in this study lays the foundation for the future development of ergonomic assistive devices using the OpenSim simulation pipeline.