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Aquatic insects have developed versatile locomotion mechanisms that have served as a source of inspiration for decades in the development of small‐scale swimming robots. However, despite recent advances in the field, efficient, untethered, and integrated powering, actuation, and control of small‐scale robots remains a challenge due to the out‐of‐equilibrium and dissipative nature of the driving physical and chemical phenomena. Here, we have designed small‐scale, bioinspired aquatic locomotors with programmable deterministic trajectories that integrate self‐propelled chemical motors and photoresponsive shape‐morphing structures. A Marangoni motor system is developed integrating structural protein networks that self‐regulate the release of chemical fuel with photochemical liquid crystal network (LCN) actuators that change their shape and deform in and out of the surface of water. While the diffusion of fuel from the motor system regulates the propulsion, the dissipative photochemical deformation of LCNs provides locomotors with control over the directionality of motion at the air‐water interface. This approach gives access to five different but interchangeable modes of locomotion within a single swimming robot via morphing of the soft structure. The proposed design, which mimics the mechanisms of surface gliding and posture change of semiaquatic insects such as water treaders, offers solutions for autonomous swimming soft robots via untethered and orthogonal power and control.
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This content will become publicly available on April 1, 2027
Photochemical Fuel Carrier Molecules for Robotic Embodied Energy
ABSTRACT The downsizing of mobile robots faces obstacles in power and control as conventional electromechanical systems do not scale favorably with mass and size. Despite recent advancements in functional materials, enabling efficient energy storage, structural integration, and on‐demand energy release in small‐scale robots remains a challenge. Inspired by metabolic strategies in animals, we designed a fuel carrier molecule for embodied energy in small‐scale swimming robots. We integrated an ultralow surface tension unit into a photolabileo‐nitrobenzyl derivative to yield a novel photoresponsive molecule for fuel storage and controlled release. Combining these two properties, carrier molecules undergo bond scission under UV light to release fuel and locally manipulate surface tension to generate Marangoni flows. We incorporated this fuel carrier into an easily processable polymer composite to enable its application as a structural component with embodied energy and control. We implemented this approach in Marangoni micropump systems, surface‐tension‐active particle transportation, and untethered hybrid microrobots that combine photochemical on–off propulsion with magnetic control. This materials platform serves as a versatile solution to store fuel and energy in structural components and release it on demand with precision, opening new opportunities for embodied energy design in microrobots, soft devices, and active matter systems.
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- Award ID(s):
- 2309029
- PAR ID:
- 10683489
- Publisher / Repository:
- Wiley
- Date Published:
- Journal Name:
- Advanced Materials
- Volume:
- 38
- Issue:
- 23
- ISSN:
- 0935-9648
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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