Affiliations: Department of Mechanical and Nuclear Engineering, The Pennsylvania State University, University Park, PA 16802, USA | Department of Biology, The University of North Carolina at Chapel Hill, Chapel Hill, NC 27599, USA | Department of Electrical and Computer Engineering, Clemson University, Clemson, SC 29634, USA
Abstract: Traditional robots have rigid underlying structures that limit their ability to interact with their environment. For example, conventional robot manipulators have rigid links and can manipulate objects using only their specialised end effectors. These robots often encounter difficulties operating in unstructured and highly congested environments. A variety of animals and plants exhibit complex movement with soft structures devoid of rigid components. Muscular hydrostats (e.g. octopus arms and elephant trunks) are almost entirely composed of muscle and connective tissue and plant cells can change shape when pressurised by osmosis. Researchers have been inspired by biology to design and build soft robots. With a soft structure and redundant degrees of freedom, these robots can be used for delicate tasks in cluttered and/or unstructured environments. This paper discusses the novel capabilities of soft robots, describes examples from nature that provide biological inspiration, surveys the state of the art and outlines existing challenges in soft robot design, modelling, fabrication and control.
Keywords: soft robots, muscular hydrostats, electroactive polymers, pneumatic air muscles
