Continuous, autonomous subsurface cargo shuttling by nature-inspired meniscus-climbing systems

Area of Science:

• Biomimetic systems
• Soft robotics
• Surface science

Background:

• Water-walking insects utilize capillary forces and surface tension for locomotion.
• Controlling the meniscus is crucial for insect survival, predation, and escape.
• Existing synthetic systems lack autonomous subsurface cargo transport capabilities.

Purpose of the Study:

• To develop autonomous, aqueous-based synthetic systems capable of subsurface cargo transport.
• To mimic the meniscus-climbing behavior of water-walking insects.
• To explore applications in autonomous delivery and micro-robotics.

Main Methods:

• Synthetic coacervate sacs and hydrogel droplets were engineered to interact with the water surface meniscus.
• Contact angle manipulation was achieved by controlling normal forces on the synthetic systems.
• Buoyancy-induced cyclic shuttling of cargo was demonstrated in aqueous environments.

Main Results:

• The synthetic systems successfully overcame the meniscus barrier, shuttling cargo subsurface.
• Contact angle reversal was controlled by external forces, enabling ascent and descent.
• Continuous cargo shuttling was sustained by reactant diffusion from the surrounding medium.

Conclusions:

• Autonomous synthetic systems can mimic insect-like meniscus traversal for cargo transport.
• Controlled surface tension manipulation offers a pathway for subsurface delivery.
• These findings pave the way for advanced autonomous reaction and delivery systems.