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Principles and methods for stiffness modulation in soft robot design and development

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Abstract

Compared to traditional rigid robots, soft robots, primarily made of deformable, or less rigid materials, have good adaptability, conformability and safety in interacting with the environment. Although soft robots have shown great potentials for extended applications and possibilities that are impossible or difficult for rigid body robots, it is of great importance for them to have the capability of controllable stiffness modulation. Stiffness modulation allows soft robots to have reversible change between the compliant, or flexible state and the rigid state. In this paper, we summarize existing principles and methods for stiffness modulation in soft robotic development and divide them into four groups based on their working principles. Acoustic-based methods have been proposed as the potential fifth group in stiffness modulation of soft robots. Initial design proposals based on the proposed acoustic method are presented, and challenges in further development are highlighted.

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Abbreviations

SMP:

Shape memory polymer

SMA:

Shape memory alloy

LMPA:

Low melting point alloy

ERF:

Electro-rheological fluid

MRF:

Magneto-rheological fluid

MIS:

Minimally invasive surgery

DEA:

Dielectric elastomer actuator

PLA:

Polylactic acid

ABS:

Acrylonitrile butadiene styrene

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Author information

Authors and Affiliations

  1. College of Information Engineering, Shenzhen University, Shenzhen, China

    Yang Yang

  2. Department of Mechanical Engineering, The University of Hong Kong, Pokfulam Road, Pokfulam, Hong Kong, China

    Yang Yang, Yingtian Li & Yonghua Chen

Authors
  1. Yang Yang
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  2. Yingtian Li
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  3. Yonghua Chen
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Contributions

YY, YTL and YHC designed the overall study. YY and YHC wrote the manuscript. YTL performed the experiment of acoustic liquids actuation. YY and YTL analyzed the data. YHC supervised the study. All authors commented on the paper.

Corresponding author

Correspondence to Yonghua Chen.

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The authors declare that they have no conflict of interest.

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Yang, Y., Li, Y. & Chen, Y. Principles and methods for stiffness modulation in soft robot design and development. Bio-des. Manuf. 1, 14–25 (2018). https://doi.org/10.1007/s42242-018-0001-6

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