Fatigue assessment for back-support exoskeletons during repetitive lifting tasks

Area of Science:

• Biomechanics
• Occupational Health
• Robotics

Background:

• Worker fatigue, particularly low back pain, significantly impacts safety and productivity across industries.
• Exoskeletons offer a potential solution for mitigating fatigue, but their real-world assessment is challenging.
• Current assessment methods often rely on direct human body measurements like electromyography (EMG), which have limitations in practical scenarios.

Purpose of the Study:

• To develop and validate a simulation-based method for evaluating the impact of exoskeletons on lumbar fatigue.
• To create a tool that combines exoskeleton modeling with human body simulation for biomechanical analysis.
• To provide a reliable alternative or supplement to direct EMG measurements for assessing exoskeleton effectiveness.

Main Methods:

• Developed a computational method integrating an exoskeleton model with a human body simulation.
• Utilized the combined model to estimate biomechanical variables related to lumbar fatigue.
• Validated the simulation's accuracy by comparing estimated strength and tendency with electromyography (EMG) data from repetitive lifting tasks.

Main Results:

• The simulation method accurately estimated strength and tendency, showing strong correlation with EMG device results.
• The developed method demonstrated similarity to direct EMG measurements in symmetrical repetitive lifting tasks.
• The simulation approach proved capable of predicting and simulating lumbar fatigue following recorded human motion.

Conclusions:

• The combined exoskeleton and human body simulation method is a viable tool for evaluating exoskeleton effects on lumbar fatigue.
• This simulation approach offers a practical and potentially more accessible alternative to direct EMG measurements.
• Findings can guide exoskeleton manufacturers in designing safer and more effective products for reducing occupational fatigue.