The Design Principles And Methods Of The Lower Limb Multi-Articular Passive Exoskeleton

Walking is an essential locomotion in human daily life.Due to various demands such as aging,obesity,arms race,etc.,the use of science and technology to realize the second revolution of human walking has not only important academic value but also important practical significance.Passive lower limb exoskeleton is an important part of the field of mechanically assisted walking.In this paper,the musculoskeletal simulations are used to reveal the compensation strategies of lower limb muscles.Combining the mechanism of the lower limb during walking,an effective method for embedding elastic multi-joint exotendon into the lower limb was proposed.Based on this method,we have developed a passive multi-joint exoskeleton that can improve human walking efficiency,and the experiments have proved that the exoskeleton can significantly reduce the metabolic cost of walking.Our research results have made innovative breakthroughs in the field of passive exoskeleton,and provided new principles and methods for the design of assisted passive exoskeleton.The main research contents include:(1)Compensation strategies of lower limb muscles with elastic exotendon.Based on the highly efficient characteristics of the elastic exotendon,a lower limb musculoskeletal model with a single-joint exotendon and a lower limb musculoskeletal model with a multi-joint exotendon are established.And the unique compensation strategies of lower limb muscles with the assistance of elastic exotendon are proposed by using musculoskeletal simulations in Open Sim.(2)Effectively assisted embedding principle of multi-joint elastic exotendon in lower limb.Based on the walking process and the kinematics of the lower limb joints,the anatomical characteristics and muscle biomechanical characteristics of the hip and knee joints are analyzed.According to the dynamic matching characteristics of hip and knee joints during walking and the compensation strategies of lower limb muscles,the optimal energy storage and release phase of the multi-joint exotendon embedded in the lower limb that can reduce the activation of muscles and the metabolic cost of walking are determined.It provides a theoretical basis for the design of the multi-joint passive exoskeleton based on elastic exotendon.(3)The design of the lower limb multi-joint passive exoskeleton prototype.Accord-ing to the optimal energy storage and release phase of the multi-joint exotendon,a mechanical control mechanism that can induce energy storage and release of the elastic exotendon from the joint angle is designed.Based on the forces of the exoskeleton,the surface of the human body,comfort,and restraint methods,the wearable structure of the exoskeleton is designed,then the design principle of the multi-joint passive exoskeleton device is completed.(4)Comprehensive evaluation of the exoskeleton prototype during walking.Design experimental protocol based on factors such as adaptation,individual differences,and the best effects of the exoskeleton.And using a variety of equipment to measure data such as metabolic consumption,electromyographic,kinematics,and torque of the exoskeleton during walking to comprehensively evaluate the effects of the exoskeleton and verify the principle proposed in this paper.