Applicability of an Active Back-Support Exoskeleton to Carrying Activities

Area of Science:

• Biomechanics
• Human-Robot Interaction
• Ergonomics

Background:

• Work-related lower back pain is a significant issue, often linked to lifting activities.
• Occupational back-support exoskeletons are increasingly used to mitigate this pain.
• Exoskeletons may also benefit other tasks like carrying, pushing, and pulling.

Purpose of the Study:

• To compare lower back loading during carrying versus lifting tasks.
• To investigate the need for task-specific assistive strategies in exoskeletons.
• To evaluate a constant torque control strategy for exoskeletons during carrying.

Main Methods:

• Experimental campaign involving 9 human subjects.
• Utilized a control strategy commanding constant torques.
• Measured lower back loading and lower limb joint ranges of motion.

Main Results:

• The constant torque control strategy reduced overall lumbar activity by up to 12%.
• This strategy constrained hip and knee range of motion by approximately 10%.
• Findings suggest a trade-off between back support and leg mobility.

Conclusions:

• Task recognition and tailored controller design are crucial for enhancing exoskeleton versatility.
• Different assistive strategies may be required for different occupational tasks (e.g., lifting vs. carrying).
• Optimizing exoskeleton control can improve adaptability and user benefit across diverse work activities.