Can humans perceive the metabolic benefit provided by augmentative exoskeletons?

Area of Science:

• Biomechanics
• Human-Computer Interaction
• Robotics

Background:

• Augmentative exoskeletons aim to enhance human physical capabilities beyond natural limitations.
• While exoskeletons can improve walking efficiency by 10-15%, current technologies are largely confined to laboratory settings.
• Widespread adoption requires exoskeletons to offer a perceivable benefit to users, not just measurable efficiency gains.

Purpose of the Study:

• To quantify the perceptual threshold of metabolic efficiency benefits during exoskeleton-assisted walking.
• To determine the minimum assistance level required for users to reliably detect a change in their metabolic rate.

Main Methods:

• Ten participants walked continuously while wearing bilateral ankle exoskeletons.
• Exoskeleton assistance levels were varied in 2-minute intervals.
• Participants provided feedback on their perceived metabolic rate to estimate the perceptual threshold.

Main Results:

• Participants could detect a metabolic rate change of 22.7% (SD: 17.0%) with 75% accuracy.
• On average, current augmentative exoskeletons do not provide a reliably perceivable metabolic benefit in the short term.

Conclusions:

• The inability of users to perceive benefits may hinder the long-term adoption and viability of exoskeleton technology.
• Future exoskeleton design should focus on increasing the perceivable benefits to enhance user experience and market acceptance.
• The methods and findings can guide researchers and designers in developing more effective and user-centric exoskeletons.