Physical and Cognitive Load Effects Due to a Powered Lower-Body Exoskeleton

Area of Science:

• Human-computer interaction
• Human factors engineering
• Military technology

Background:

• US warfighters carry heavy equipment, increasing physical burden.
• Exoskeletons are being developed to reduce this load.
• Cognitive effects of exoskeletons are not well understood.

Purpose of the Study:

• To determine the effects of powered exoskeletons on physical and cognitive performance.
• To evaluate how exoskeletons influence task performance and workload in a simulated military patrol setting.

Main Methods:

• Twelve military members performed a simulated patrol task under three conditions: powered exoskeleton (PWR), unpowered exoskeleton (UNP), and no exoskeleton (OFF).
• Participants completed physical tasks (following a confederate over obstacles) and cognitive tasks (audio and visual monitoring).
• Measures included reaction times, lag times, and perceived workload (NASA-TLX).

Main Results:

• Exoskeleton use (UNP) increased variability in maintaining pace.
• Powered exoskeletons (PWR) significantly slowed visual reaction time for some subjects compared to no exoskeleton (OFF).
• Perceived workload (NASA-TLX) was higher with both powered (PWR) and unpowered (UNP) exoskeletons compared to no exoskeleton (OFF).

Conclusions:

• Exoskeletons can impact cognitive performance and increase perceived workload.
• Individual variability in response to exoskeletons is significant.
• Cognitive fit and user differences must be considered in exoskeleton design and implementation for military applications.