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Untethered soft robotics


Research in soft matter engineering has introduced new approaches in robotics and wearable devices that can interface with the human body and adapt to unpredictable environments. However, many promising applications are limited by the dependence of soft systems on electrical or pneumatic tethers. Recent work in soft actuation and electronics has made removing such cords more feasible, heralding a variety of applications from autonomous field robotics to wireless biomedical devices. Here we review the development of functional untethered soft robotics. We focus on recent advances in soft robotic actuation, sensing and integration as they relate to untethered systems, and consider the key challenges the field faces in engineering systems that could have practical use in real-world conditions.

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Author information

S.I.R. compiled the references and wrote the manuscript. C.M. and R.J.W conceived and structured the paper. All authors contributed to editing and reviewing.

Competing interests

The authors declare no competing financial interests.

Correspondence to Carmel Majidi.

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Further reading

Fig. 1: Overview of soft robotic systems.
Fig. 2: Methods of soft actuation.
Fig. 3: Modulus and conductivity of various materials in soft robotics.
Fig. 4: Advances in soft sensing, conductivity and artificial skin.
Fig. 5: Implementation of soft actuators into robotic systems.
Fig. 6: Fully untethered robotic systems.