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Soft material robots are uniquely suited to address engineering challenges in extreme environments in new ways that traditional rigid robot embodiments cannot. Soft robot material flexibility, resistance to brittle fracture, low thermal conductivity, biostability, and self-healing capabilities present new solutions advantageous to specific environmental conditions. In this review, we examine the requirements for building and operating soft robots in various extreme environments, including within the human body, underwater, outer space, search and rescue sites, and confined spaces. We analyze the implementations of soft robotic devices, including actuators and sensors, which meet these requirements. Besides the structure of these devices, we explore ways to expand the use of soft robots in extreme environments with design optimization, control systems, and their future applications in educational and commercial products. We further discuss the current limitations of soft robots recognizing challenges to compliance, strength, and control. With this in mind, we present arguments for the future of robotics in which hybrid (rigid and soft) structures meet complex environmental needs.
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Simulation and Fabrication of Soft Robots with Embedded Skeletons
Soft robots can be incredibly robust and safe but typically fail to match the strength and precision of rigid robots. This dichotomy between soft and rigid is recently starting to break down, with emerging research interest in hybrid soft-rigid robots. In this work, we draw inspiration from Nature, which achieves the best of both worlds by coupling soft and rigid tissues—like muscle and bone—to produce biological systems capable of both robustness and strength. We present foundational, general-purpose pipelines to simulate and fabricate cable-driven soft-rigid robots with embedded skeletons. We show that robots built using these methods can fluidly mimic biological systems while achieving greater force output and external load resistance than purely soft robots. Finally, we show how our simulation and fabrication pipelines can be leveraged to create more complex robots and do model- based control.
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- Award ID(s):
- 1830901
- PAR ID:
- 10356382
- Date Published:
- Journal Name:
- Proceedings of the IEEE International Conference on Robotics and Automation
- Page Range / eLocation ID:
- 5205 to 5211
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript1.0
- Conference Paper:
- https://doi.org/10.1109/ICRA46639.2022.9811844
