Materials and technologies used to make soft robots that can safely interact with humans are avidly explored. A wealth of applications are in reach for soft robots but a number of challenges remain.
Soft robots are made from soft, elastic materials and offer unique opportunities in areas in which conventional rigid robots are not viable; for example, for drug delivery, non-invasive surgical procedures, as assistive devices, prostheses or artificial organs. The emerging field of soft robotics draws together materials scientists, mechanical and biomedical engineers, and researchers of intelligent systems. The inspiration for the design of many soft robotic systems comes from nature. This focus issue features contributions from leaders in key areas of this multi-disciplinary field with articles about bioinspired microrobots, 3D printing and origami folding of soft robots, actuation and control strategies, the use of hydrogels for soft robots and biomedical applications. Moreover, challenges, design concepts and milestones on the road to clinical translation are discussed.
3D printing can be used to directly fabricate soft robots. This Review discusses advances in 3D printing technologies and soft materials for the fabrication of soft robotic systems with sophisticated capabilities, such as 3D movement and responsiveness to the environment.
Inspired by biological systems, engineers are exploring origami folding with smart material actuation to enable intrinsically actuated designs with complex functionalities and easy fabrication. This Review highlights recent advances in the design, fabrication and control of these origami robots.
Microrobots are envisioned to revolutionize microsurgery and targeted drug delivery. Their design, operation, locomotion and interaction with the environment are inspired by microorganisms. This Review highlights soft, responsive and active materials for the development of (semi-)autonomous microrobots.
Hydrogel ionotronics employ hydrogels as stretchable, transparent, ionic conductors for the development of ionotronic devices, such as artificial muscles, skins and axons. This Review discusses the mechanical properties and chemistry of materials for hydrogel ionotronic devices and highlights possible applications.
Soft robots have broad applications in medicine. In this Review, biomedical applications, including surgery, drug delivery, prostheses, wearable devices and artificial organs, are discussed in the context of materials, actuation strategies and challenges.
Soft small robots offer the opportunity to non-invasively access human tissue to perform medical operations and deliver drugs; however, challenges in materials design, biocompatibility and function control remain to be overcome for soft robots to reach the clinic.
Soft robots promise solutions for a wide range of applications that cannot be achieved with traditional, rigid-component robots. A key challenge is the creation of robotic structures that can vary their stiffness at will, for example, by using antagonistic actuators, to optimize their interaction with the environment and be able to exert high forces.
The field of soft wearable robotics offers the opportunity to wear robots like clothes to assist the movement of specific body parts or to endow the body with functionalities. Collaborative efforts of materials, apparel and robotics science have already led to the development of wearable technologies for physical therapy. Optimizing the human–robot system by human-in-the-loop approaches will pave the way for personalized soft wearable robots for a variety of applications.
‘Push-button’ or fully automated manufacturing would enable the production of robots with zero intervention from human hands. Realizing this utopia requires a fundamental shift from a sequential (design–materials–manufacturing) to a concurrent design methodology.