Study on the human-machine coupling model and assistive characteristics of a lower limb wearable device

ObjectiveAiming at the problems of large volume and high energy consumption of existing lower limb exoskeleton devices, a lower limb wearable device with an ankle joint assistive spring was designed to reduce muscle metabolism without increasing additional human consumption and improve the assistive effect.MethodsFirstly, the structure of the human lower limb skeleton was analyzed, and the structural design of the lower limb wearable device was completed. Secondly, a human-machine coupling numerical model was constructed to carry out simulation analysis of assistive characteristics under multiple working conditions. Finally, biomechanical simulations were performed using OpenSim software to simulate the walking process of humans wearing the device and verify its effectiveness.ResultsThe results indicate that at normal walking speed, after wearing the device, the average peak torque of the ankle joint decreases by 27.4%, the total human muscle metabolism decreases by 5.3%, and the metabolism of the main calf muscle groups is reduced, which effectively alleviate the muscle load of the wearer and achieve a good assistive effect. The research can provide reference for the design of passive assistive devices.