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Cyclic actuation is critical for driving motion and transport in living systems, ranging from oscillatory motion of bacterial flagella to the rhythmic gait of terrestrial animals. These processes often rely on dynamic and responsive networks of oscillators—a regulatory control system that is challenging to replicate in synthetic active matter. Here, we describe a versatile platform of light-driven active particles with interaction geometries that can be reconfigured on demand, enabling the construction of oscillator and spinner networks. We employ optically induced Marangoni trapping of particles confined to an air–water interface and subjected to patterned illumination. Thermal interactions among multiple particles give rise to complex coupled oscillatory and rotational motions, thus opening frontiers in the design of reconfigurable, multiparticle networks exhibiting collective behavior.
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Emergence of traveling waves in linear arrays of electromechanical oscillators
Abstract Traveling waves of mechanical actuation provide a versatile strategy for locomotion and transport in both natural and engineered systems across many scales. These rhythmic motor patterns are often orchestrated by systems of coupled oscillators such as beating cilia or firing neurons. Here, we show that similar motions can be realized within linear arrays of conductive particles that oscillate between biased electrodes through cycles of contact charging and electrostatic actuation. The repulsive interactions among the particles along with spatial gradients in their natural frequencies lead to phase-locked states characterized by gradients in the oscillation phase. The frequency and wavelength of these traveling waves can be specified independently by varying the applied voltage and the electrode separation. We demonstrate how traveling wave synchronization can enable the directed transport of material cargo. Our results suggest that simple energy inputs can coordinate complex motions with opportunities for soft robotics and colloidal machines.
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- Award ID(s):
- 1738191
- PAR ID:
- 10154126
- Publisher / Repository:
- Nature Publishing Group
- Date Published:
- Journal Name:
- Communications Physics
- Volume:
- 1
- Issue:
- 1
- ISSN:
- 2399-3650
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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