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Design, fabrication and control of soft robots

Abstract

Conventionally, engineers have employed rigid materials to fabricate precise, predictable robotic systems, which are easily modelled as rigid members connected at discrete joints. Natural systems, however, often match or exceed the performance of robotic systems with deformable bodies. Cephalopods, for example, achieve amazing feats of manipulation and locomotion without a skeleton; even vertebrates such as humans achieve dynamic gaits by storing elastic energy in their compliant bones and soft tissues. Inspired by nature, engineers have begun to explore the design and control of soft-bodied robots composed of compliant materials. This Review discusses recent developments in the emerging field of soft robotics.

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Figure 1: Mobile soft-robotic systems inspired by a range of biological systems.
Figure 2: Approximate tensile modulus (Young's modulus) of selected engineering and biological materials.
Figure 3: Grasping and manipulation, which are canonical challenges in robotics, can be greatly simplified with soft robotics.
Figure 4: Cross-section of common approaches to actuation of soft-robot bodies in resting (left) and actuated (right) states.
Figure 5: A soft robotic fish.

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Acknowledgements

The authors would like to thank A. Marchese and R. Katzschmann for their insightful comments and suggestions in editing this paper. This work was done with partial support from the National Science Foundation grant number IIS-1226883, for which we are grateful.

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Rus, D., Tolley, M. Design, fabrication and control of soft robots. Nature 521, 467–475 (2015). https://doi.org/10.1038/nature14543

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