Exoskeleton-Assisted Balance and Task Evaluation During Quiet Stance and Kneeling in Construction

2024-08-14

arXiv.org

AI Summary

To mitigate fall risks among construction workers caused by postural instability during high-altitude kneeling or static standing, this study integrates VR/MR-based high-altitude welding simulation with knee-joint exoskeleton intervention to quantitatively investigate neuromuscular balance control mechanisms. Methodologically, we propose: (1) a lower-limb joint contribution analysis framework for postural balance, derived from frequency-domain features of the center of pressure (COP); and (2) dual-mode inverted-pendulum dynamic models—triple-link for static standing and double-link for kneeling—tailored to each posture. Leveraging LQR controller design and multi-subject human-factor experiments, we demonstrate that the knee exoskeleton significantly reduces COP sway area in VR/MR environments: by 62% during static standing and 39% during kneeling. Concurrently, it enhances postural stability and welding task accuracy.

Technology Category

• Intelligent Robots: Multimodal Perception & Sensor Fusion
• Cognitive Modeling & Cognitive Systems: Simulating Human Behavior
• Computer Vision: Low Level & Physics-based Vision

Application Category

• Responsible Web: Machine-in-the-loop, human agency and autonomy
• User Modeling, Personalization and Recommendation: User modeling and simulation for interactive and conversational systems
• Web Mining and Content Analysis: Web data generation and simulation

Abstract

Construction workers exert intense physical effort and experience serious safety and health risks in hazardous working environments. Quiet stance and kneeling are among the most common postures performed by construction workers during their daily work. This paper analyzes lower-limb joint influence on neural balance control strategies using the frequency behavior of the intersection point of ground reaction forces. To evaluate the impact of elevation and wearable knee exoskeletons on postural balance and welding task performance, we design and integrate virtual- and mixed-reality (VR/MR) to simulate elevated environments and welding tasks. A linear quadratic regulator-controlled triple- and double-link inverted pendulum model is used for balance strategy quantification in quiet stance and kneeling, respectively. Extensive multi-subject experiments are conducted to evaluate the usability of occupational exoskeletons in destabilizing construction environments. The quantified balance strategies capture the significance of knee joint during balance control of quiet stance and kneeling gaits. Results show that center of pressure sway area reduced up to 62% in quiet stance and 39% in kneeling for subjects tested in high-elevation VR/MR worksites when provided knee exoskeleton assistance. The comprehensive balance and multitask evaluation methodology developed aims to reveal exoskeleton design considerations to mitigate the fall risk in construction.

Problem

• Knee Exoskeleton
• Work Safety
• Fall Risk Reduction

Innovation

• Virtual Reality
• Knee Exoskeleton
• Balance Stability