Field-directed and self-propelled colloidal assembly have been used to build micromachines capable of performing complex motions and functions. However, integrating heterogeneous components into micromachines with specified structure, dynamics and function is still challenging. Here, we describe the dynamic self-assembly of mobile micromachines with desired configurations through pre-programmed physical interactions between structural and motor units. The assembly is driven by dielectrophoretic interactions, encoded in the three-dimensional shape of the individual parts. Micromachines assembled from magnetic and self-propelled motor parts exhibit reconfigurable locomotion modes and additional rotational degrees of freedom that are not available to conventional monolithic microrobots. The versatility of this site-selective assembly strategy is demonstrated on different reconfigurable, hierarchical and three-dimensional micromachine assemblies. Our results demonstrate how shape-encoded assembly pathways enable programmable, reconfigurable mobile micromachines. We anticipate that the presented design principle will advance and inspire the development of more sophisticated, modular micromachines and their integration into multiscale hierarchical systems.
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Any data supporting the findings of this study are available within the Article and its Supplementary Information and are available from the corresponding author upon reasonable request.
The open-source and commercial software used for data analyses are referenced in the Methods.
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The authors thank V. Liimatainen for helping with editing the manuscript. Y.A. thanks the Alexander von Humboldt Foundation for a Humboldt Postdoctoral Research Fellowship. A.F.D. acknowledges the Swiss National Science Foundation for the Scientific Exchange Grant no. IZSEZ0_181526. This work is funded by the Max Planck Society.
The authors declare no competing interests.
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Supplementary video legends 1–8, Supplementary Notes 1–3, Supplementary Figs. 1–14, Supplementary references.
Assembly and translation of a compound microvehicle with magnetic actuators.
Pick-and-place manipulation of non-magnetic objects using reversible assembly.
Tuning coupling stiffness of the assembly by modulating dielectrophoretic interactions.
Shape-encoded assembly of magnetic microactuators.
Shape-encoded assembly of self-propelled microactuators.
Reconfigurable mobile micromachines.
Hierarchical assembly of mobile micromachines.
Three-dimensional (3D) microactuator manipulation and assembly.
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Alapan, Y., Yigit, B., Beker, O. et al. Shape-encoded dynamic assembly of mobile micromachines. Nat. Mater. 18, 1244–1251 (2019). https://doi.org/10.1038/s41563-019-0407-3
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