Bioinspired Soft Microactuators

Research output: Journal Publications and ReviewsRGC 21 - Publication in refereed journalpeer-review

27 Scopus Citations
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  • Rifei Chen
  • Chunmei Zhou
  • Michael Aizenberg
  • Joanna Aizenberg
  • Liqiu Wang


Original languageEnglish
Article number2008558
Journal / PublicationAdvanced Materials
Issue number21
Online published16 Apr 2021
Publication statusPublished - 27 May 2021
Externally publishedYes


Soft actuators have the potential of revolutionizing the field of robotics. However, it has been a long-standing challenge to achieve simultaneously: i) miniaturization of soft actuators, ii) high contrast between materials properties at their “on” and “off” states, iii) significant actuation for high-payload mechanical work, and iv) ability to perform diverse shape transformations. This challenge is addressed by synergistically utilizing structural concepts found in the dermis of sea cucumbers and the tendrils of climbing plants, together with microfluidic fabrication to create diatomite-laden hygroscopically responsive fibers with a discontinuous ribbon of stiff, asymmetrically shaped, and hygroscopically inactive microparticles embedded inside. The microactuators can undergo various deformations and have very high property contrast ratios (20–850 for various mechanical characteristics of interest) between hydrated and dehydrated states. The resulting energy density, actuation strain, and actuation stress are shown to exceed those of natural muscle by ≈4, >2, and >30 times, respectively, and their weight-lifting ratio is 2–3 orders of magnitude higher than the value of recent hygroscopic actuators. This work offers a new and general way to design and fabricate next-generation soft microactuators, and thus advances the field of soft robotics by tailoring the structure and properties of deformable elements to suit a desired application.

Research Area(s)

  • bioinspiration, high property contrast, hygroscopic materials, microactuators, programmable materials actuation

Bibliographic Note

Publisher Copyright: © 2021 Wiley-VCH GmbH

Citation Format(s)

Bioinspired Soft Microactuators. / Zhu, Pingan; Chen, Rifei; Zhou, Chunmei et al.
In: Advanced Materials, Vol. 33, No. 21, 2008558, 27.05.2021.

Research output: Journal Publications and ReviewsRGC 21 - Publication in refereed journalpeer-review