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Transforming machines capable of continuous 3D shape morphing and locking

Nature Machine Intelligence volume 7, pages 703–715 (2025) Cite this article

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Abstract

Inspired by natural species that leverage morphological changes to realize multiple locomotion modes, diverse multimodal robots have been reported. While developments of small-scale actuators with continuous shape morphing and locking capabilities controlled by the same energy source are crucial for miniaturization of untethered multimodal robots, it remains elusive. We introduce a synergistic design concept of small-scale continuously morphable actuators (CMAs) that harness precisely programmable actuation deformation of liquid crystal elastomer to achieve continuous shape morphing and high stiffness variation of shape memory polymer to lock geometric configuration, both through electrothermal control. Lego-inspired design strategy allows customized construction of complexly shaped CMAs (for example, ‘transformer’, ‘aircraft’ and ‘turtle’) through rational assembly of elementary actuator units with different ranges of accessible geometric configurations. The powerful shape morphing and locking capabilities, as well as the relatively high load-bearing capacity of the CMAs, allow for developments of versatile exoskeletons that can integrate a diversity of functional components. Demonstrations of unique small-scale transforming machines, such as morphable displays with a rich diversity of three-dimensional geometries, a wheeled microrobot capable of transformation among ‘sports car’, ‘winged car’ and ‘van’, and a lightweight untethered terrestrial–aerial microrobot, suggest a broad spectrum of applications.

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Fig. 1: Design concept, principle and demonstration of actuators capable of continuous shape morphing and locking.
The alternative text for this image may have been generated using AI.
Fig. 2: Design methods and performances of the basic CMA.
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Fig. 3: Geometrically sophisticated actuators with versatile shape-morphing capabilities.
The alternative text for this image may have been generated using AI.
Fig. 4: Continuously morphable 3D displays and wheeled microrobot.
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Fig. 5: Conceptual design and demonstration of a lightweight terrestrial–aerial microrobot.
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Data availability

All data supporting the results of this study are available in the paper and its Supplementary Information. The source data for Figs. 1–5 are available via Zenodo at https://doi.org/10.5281/zenodo.14906294 (ref. 67).

Code availability

The code for the IR module of the terrestrial–aerial microrobot is available via Zenodo at https://doi.org/10.5281/zenodo.14906294 (ref. 67).

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Acknowledgements

This work was supported by the National Natural Science Foundation of China (grant no. 12225206 to Y.Z.), the New Cornerstone Science Foundation through the XPLORER PRIZE (to Y.Z.), the Beijing Natural Science Foundation (grant no. L242069 to Y.Z.), the Institute for Guo Qiang, Tsinghua University (grant no. 2021GQG1009 to Y.Z.) and the Tsinghua National Laboratory for Information Science and Technology (to Y.Z.).

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Authors and Affiliations

  1. Mechano-X Institute, Applied Mechanics Laboratory, Department of Engineering Mechanics, Tsinghua University, Beijing, P.R. China

    Shiwei Xu, Xiaonan Hu, Ruoxi Yang, Chuanqi Zang, Yue Xiao, Wenbo Liu, Wenbo Pang, Renheng Bo, Qing Liu, Youzhou Yang, Yuchen Lai, Jun Wu & Yihui Zhang

  2. State Key Laboratory of Flexible Electronics Technology, Tsinghua University, Beijing, P.R. China

    Shiwei Xu, Xiaonan Hu, Ruoxi Yang, Chuanqi Zang, Yue Xiao, Wenbo Liu, Wenbo Pang, Renheng Bo, Qing Liu, Youzhou Yang, Yuchen Lai, Jun Wu & Yihui Zhang

  3. School of Mechanical Engineering and Automation, Beihang University, Beijing, P.R. China

    Lei Li, Bocheng Tian & Li Wen

  4. Department of Mechanical Engineering, Tsinghua University, Beijing, P.R. China

    Huichan Zhao

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  1. Shiwei Xu
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Contributions

Y.Z. designed and supervised the research. S.X. led the design, analysis, fabrication and characterization of CMAs. S.X. led the design, fabrication and characterization of morphable displays and wheeled microrobots, with assistance from R.Y. S.X. led the design, fabrication and characterization of terrestrial–aerial microrobots, with assistance from X.H., C.Z., L.L., Y.X., W.L., B.T., W.P., R.B., Q.L., Y.Y., Y.L. and J.W. L.W. and H.Z. provided scientific and experimental advice. S.X. and Y.Z. wrote the paper and designed the figures. All authors commented on the paper.

Corresponding author

Correspondence to Yihui Zhang.

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Nature Machine Intelligence thanks Michael Pieber, Jianguo Zhao and the other, anonymous, reviewer(s) for their contribution to the peer review of this work.

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Supplementary information

Supplementary Information (download PDF )

Supplementary Notes 1–7, Figs. 1–51, Tables 1–4 and Videos 1–9.

Reporting Summary (download PDF )

Supplementary Video 1 (download MP4 )

Design concept, principle and demonstration of actuators capable of continuous shape morphing and locking.

Supplementary Video 2 (download MP4 )

Two types of elementary actuator unit with complex deformation modes.

Supplementary Video 3 (download MP4 )

Assembly of elementary actuator units for constructing the transformer and turtle.

Supplementary Video 4 (download MP4 )

Assembly of elementary actuator units for constructing geometrically sophisticated actuators with versatile shape-morphing capabilities.

Supplementary Video 5 (download MP4 )

Morphable 3D displays.

Supplementary Video 6 (download MP4 )

Multimodal wheeled microrobot.

Supplementary Video 7 (download MP4 )

Terrestrial indoor locomotion of the terrestrial–aerial microrobot.

Supplementary Video 8 (download MP4 )

Multimodal indoor locomotion of the terrestrial–aerial microrobot.

Supplementary Video 9 (download MP4 )

Outdoor locomotion of the terrestrial–aerial microrobot.

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Xu, S., Hu, X., Yang, R. et al. Transforming machines capable of continuous 3D shape morphing and locking. Nat Mach Intell 7, 703–715 (2025). https://doi.org/10.1038/s42256-025-01028-4

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