Reducing Lumbar Extensor Exertion in Lifting Tasks with a Powered Back Exosuit

Area of Science:

• Biomechanics
• Human-Robot Interaction
• Occupational Health

Background:

• Lifting tasks commonly cause lumbar injuries.
• Passive exoskeletons offer some support but have limitations.
• Powered exoskeletons aim to provide greater assistance.

Purpose of the Study:

• To evaluate a cable-driven powered exosuit for reducing lumbar muscle activity and metabolic cost during lifting.
• To compare the powered exosuit against a passive exoskeleton and a no-exosuit condition.

Main Methods:

• A lightweight, cable-driven back exosuit with an impedance controller was developed.
• Ten participants performed symmetric and asymmetric lifting tasks.
• Electromyography (EMG), metabolic cost, and user preference were recorded.

Main Results:

• Both powered and passive exoskeletons significantly reduced lumbar muscle activation compared to no support.
• Neither exoskeleton significantly reduced metabolic cost during lifting.
• Users showed a preference for the powered exosuit over the passive one.

Conclusions:

• Powered exoskeletons can effectively reduce lumbar muscle activity, comparable to passive devices.
• Cable-driven powered exoskeletons may overcome limitations of heavier, rigid powered designs.
• User preference suggests powered exoskeletons are a viable alternative for ergonomic support.