Response of Passive Exoskeleton to Torso Load under Natural Gait

Abstract

Torso loads is the most common load form of daily life. Backpacks carried daily and radiation protection clothing worn by some specific workers belong to the category of torso load. When this kind of load is worn and walked by human body, it will fluctuate with the height of human centroid. For walking, what is done in this direction is useless. Under certain circumstances, such as marching, it is often required to walk with a large amount of load for a long time and the external environment cannot provide a sustainable energy supply. For the sake of to reduce the extra work required by load fluctuation in walking in passive condition, this paper first calculates the curve of human centroid change of natural gait, and obtains that the extra work required by unit mass in one gait cycle change are 0.72 J. After that, the spring mass damping model is established, and the change curve of human centroid is taken as the system input, and the energy reduction and shock absorption ability of exoskeleton models with different natural frequencies under the premise of a certain load mass is obtained, at the same time, the load weight ratio curve and theoretical energy reduction efficiency curve required to achieve energy reduction effect under different damping ratios are drawn. That provides theoretical basis of designing structural stiffness and damping for related research, and has high application value.