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  • Perspective
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Colloidal robotics

Abstract

Robots have components that work together to accomplish a task. Colloids are particles, usually less than 100 µm, that are small enough that they do not settle out of solution. Colloidal robots are particles capable of functions such as sensing, computation, communication, locomotion and energy management that are all controlled by the particle itself. Their design and synthesis is an emerging area of interdisciplinary research drawing from materials science, colloid science, self-assembly, robophysics and control theory. Many colloidal robot systems approach synthetic versions of biological cells in autonomy and may find ultimate utility in bringing these specialized functions to previously inaccessible locations. This Perspective examines the emerging literature and highlights certain design principles and strategies towards the realization of colloidal robots.

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Fig. 1: Concepts and prototypes of CRs.
Fig. 2: Energy harvesting and storage techniques relevant for CRs.
Fig. 3: Selected examples of device integration relevant for colloidal robotics applications.
Fig. 4: Distributed computation and control in systems of CRs.

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Acknowledgements

The authors acknowledge financial support from the Air Force Office of Scientific Research under the MURI-FATE programmes (grant no. FA9550-15-1-0514), as well as support from ARO grant no. W911NF-19-1-0233 (award title: Formal Foundations of Algorithmic Matter and Emergent Computing) and partial support from ARO project W911NF-19-10372 (award title: Optical Communication with Synthetic Cells).

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Correspondence to Tomás Palacios or Michael S. Strano.

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Liu, A.T., Hempel, M., Yang, J.F. et al. Colloidal robotics. Nat. Mater. 22, 1453–1462 (2023). https://doi.org/10.1038/s41563-023-01589-y

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