Structure design and mechanical analysis of a hybrid rigid-soft knee exoskeleton based on curve beam

Abstract

The strength and endurance of human limbs can be enhanced through equipping exoskeletons or other types of wearable devices. However, long-time use of such devices may cause musculoskeletal disorders (MSDs) or potential injuries due to external shocks and vibrations. Consequently, preventing potential risks and enhancing comfortability are crucial to the design of exoskeleton. This research introduces a novel hybrid rigid-soft knee joint exoskeleton, which is well flexible and supported by two curved beams. This design is friendly and comfortable for wearers. The stiffness of the curved beam is meticulously calibrated to match the natural need of the knee joint, which provides appropriate support under vibration and impact. We employ the analytical modeling, finite element method (FEM), numerical analysis, and experimental approaches to analyze the static and dynamic properties of the knee exoskeleton system. The results confirm that the exoskeleton system exhibits reduced vibration transmissibility in low-frequency environments, and present a new methodology for the design and mechanical analysis of exoskeleton systems.