Biomechanical analysis based on a full-body musculoskeletal model for evaluating the effect of a passive lower-limb exoskeleton on lumbar load

TL;DR

This study used a full-body musculoskeletal model to biomechanically evaluate how a passive lower-limb exoskeleton affects lumbar load during different postures, revealing increased lumbar compression forces.

Contribution

It demonstrates the effectiveness of biomechanical analysis with a musculoskeletal model for assessing exoskeleton impact on lumbar load, beyond traditional posture and muscle activity analysis.

Findings

Lumbar joint compression force increased with exoskeleton use.

Biomechanical analysis provides detailed insights into lumbar load changes.

Traditional posture analysis cannot detect load increases.

Abstract

The present study investigated the effect of a passive lower-limb exoskeleton on lumbar load and verified the effectiveness of biomechanical analysis for evaluating the physical burden while wearing the exoskeleton. Twelve healthy male participants performed an assembly task under three conditions: standing and high and low sitting while wearing the exoskeleton. We mainly analyzed the joint compression force computed using the musculoskeletal model based on measurements obtained from a motion capture system and force platform. While wearing the exoskeleton, the lumbar joint compression force increased. Analysis of the joint compression force can determine the increase in the lumbar load when wearing an exoskeleton, which is not possible using the traditional analysis of posture and muscular activity. Therefore, biomechanical analysis based on a full-body musculoskeletal model provides valuable information in evaluating the effect of the exoskeleton that attempts to prevent musculoskeletal disorders.