Magnetically-driven deployable structure inspired by worms

Area of Science:

• Robotics and Biomimetics
• Materials Science
• Fluid Mechanics

Background:

• Soft robotics requires innovative actuation strategies for delicate tasks.
• Marine worms exhibit complex protrusion mechanisms that can inspire engineering solutions.

Purpose of the Study:

• To develop a magnetically driven, soft fluidic transmission mechanism for robotic actuation.
• To mimic the protrusion mechanism of the marine worm Phascolosoma stephensoni for soft robotics.
• To investigate the effect of magnetic particle concentration on actuation performance.

Main Methods:

• Fabrication of magnetic bending units using DragonSkin-10 silicone with varying NdFeB particle concentrations (40-70 wt%).
• Development of a magnetically actuated soft fluidic transmission system with an active trunk and passive proboscis.
• Analytical modeling and experimental validation of the trunk mechanism for proboscis deployment.

Main Results:

• Achieved a proboscis elongation ratio of up to 2.5 (45 mm displacement) relative to the system's initial length.
• Demonstrated improved magnetization and bending performance with increased particle content (up to ~200% gain).
• Validated trunk analytical model with a low error of 2.4% and measured internal pressure variations up to 3 kPa and tip force up to 1 N.

Conclusions:

• Optimizing magneto-mechanical properties of soft materials enables effective wireless actuation in fluidic transmission systems.
• The developed soft robotic system offers a promising approach for targeted delivery in constrained and delicate environments.
• Biomimetic design inspired by marine worms provides a viable pathway for advancing soft robotics actuation strategies.