Design of an Active Exoskeleton for Shoulder Mobility Assistance: Focus on the Elderly

Abstract

This study presents the design and construction of an active exoskeleton to assist shoulder mobility, focused on the adult population. The system is considered active due to the implementation of actuators (motors) to generate assisted movement. The prototype was manufactured using 3D printing with PLA filament, optimizing the balance between mechanical strength and lightweight components. Strength tests were conducted through finite element analysis, applying loads of 77 N and 177 N in flexion and abduction, respectively, with maximum stresses of 14.41 MPa and 115.6 MPa. These evaluations confirmed the device’s durability under typical usage conditions. Additionally, biomechanical analyses were performed using the Kinovea software, demonstrating the exoskeleton’s capability to perform shoulder flexion and abduction movements. In flexion, ranges between 73° and 102° were achieved under no-load conditions, and between 60° and 70° with an additional load of 2 lb. For abduction, angles ranged from 52° to 83° in the first scenario, and from 36° to 44° under load. Device validation was based on simulations and tests conducted with a healthy population in a controlled environment, without the participation of the target population. The results suggest that exoskeleton represents a promising approach to improving user independence and quality of life while reducing the risk of musculoskeletal injuries.