Cooperativity Model for Improving the Walking-Assistance Efficiency of the Exoskeleton

Abstract

(1) Background: To enhance the walking-assistance efficiencies of exoskeletons, this paper proposed the biomechanical-based cooperativity model based on a passive exoskeleton prototype to fill the technical gap in exoskeleton design regarding the torque transmission law between humans and exoskeletons. (2) Methods: The cooperativity model was used to solve the key system parameters based on the minimum average dispersion degree, in which the average dispersion degree algorithm based on the joint angle was designed and applied. (3) Results: The influence of the cooperativity model on the exoskeleton was indicated by comparing the walking-assistance efficiencies of the exoskeletons with the same structure but with different elastic parameters of the energy storage components, in which the exoskeleton based on the cooperativity design exhibited the highest walking-assistance performance. The walking-assistance efficiency of the exoskeleton with the optimal parameter combinations was also tested by comparing the respiratory metabolisms with and without the exoskeleton, in which the exoskeleton provided the average walking-assistance efficiency of 14.45% for more than 80% of the subjects. (4) Conclusions: The effects of the cooperativity model on exoskeletons were proven, but the accuracy and efficiency of the model still have room for improvement, especially the accuracy of the offset principle.

An Unpowered Knee Exoskeleton for Walking Assistance and Energy Capture

“…Similarly, the motion range of the hip and knee angle in this paper increased, RF activity decreased, but SEM activity increased. Generally, in order to improve the assisted efficiency of exoskeleton, power is added to the unpowered exoskeleton for the operable electronic control system, clutch or variable shock absorber [34]. This is our next research direction regarding wearable-assisted exoskeletons.…”