Soft materials possess several distinctive characteristics, such as controllable deformation, infinite degrees of freedom, and self‐assembly, which make them promising candidates for building soft ...machines, robots, and haptic interfaces. In this Review, we give an overview of recent advances in these areas, with an emphasis on two specific topics: bio‐inspired design and additive manufacturing. Biology is an abundant source of inspiration for functional materials and systems that mimic the function or mechanism of biological tissues, agents, and behaviors. Additive manufacturing has enabled the fabrication of materials and structures prevalent in biology, thereby leading to more‐capable soft robots and machines. We believe that bio‐inspired design and additive manufacturing have been, and will continue to be, important tools for the design of soft robots.
The soft side of robots: This Review gives an overview of current advances in materials with intrinsic softness as well as soft machines, robots, and haptic interfaces. The focus lies on two specific topics: bio‐inspired design and additive manufacturing.
Since the modern concepts for virtual and augmented reality are first introduced in the 1960's, the field has strived to develop technologies for immersive user experience in a fully or partially ...virtual environment. Despite the great progress in visual and auditory technologies, haptics has seen much slower technological advances. The challenge is because skin has densely packed mechanoreceptors distributed over a very large area with complex topography; devising an apparatus as targeted as an audio speaker or television for the localized sensory input of an ear canal or iris is more difficult. Furthermore, the soft and sensitive nature of the skin makes it difficult to apply solid state electronic solutions that can address large areas without causing discomfort. The maturing field of soft robotics offers potential solutions toward this challenge. In this article, the definition and history of virtual (VR) and augmented reality (AR) is first reviewed. Then an overview of haptic output and input technologies is presented, opportunities for soft robotics are identified, and mechanisms of intrinsically soft actuators and sensors are introduced. Finally, soft haptic output and input devices are reviewed with categorization by device forms, and examples of soft haptic devices in VR/AR environments are presented.
Virtual and augmented reality aims to create an immersive user experience in a fully or partially virtual environment. Haptic output and input technologies communicate touch in the real and virtual world. The maturing field of soft robotics offers solutions as intrinsically soft actuators and sensors may play a pivotal role toward more functional, sensitive, robust, and low‐cost haptic devices.
Because of their continuous and natural motion, fluidically powered soft actuators have shown potential in a range of robotic applications, including prosthetics and orthotics. Despite these ...advantages, robots using these actuators require stretchable sensors that can be embedded in their bodies for sophisticated functions. Presently, stretchable sensors usually rely on the electrical properties of materials and composites for measuring a signal; many of these sensors suffer from hysteresis, fabrication complexity, chemical safety and environmental instability, and material incompatibility with soft actuators. Many of these issues are solved if the optical properties of materials are used for signal transduction. We report the use of stretchable optical waveguides for strain sensing in a prosthetic hand. These optoelectronic strain sensors are easy to fabricate, are chemically inert, and demonstrate low hysteresis and high precision in their output signals. As a demonstration of their potential, the photonic strain sensors were used as curvature, elongation, and force sensors integrated into a fiber-reinforced soft prosthetic hand. The optoelectronically innervated prosthetic hand was used to conduct various active sensation experiments inspired by the capabilities of a real hand. Our final demonstration used the prosthesis to feel the shape and softness of three tomatoes and select the ripe one.
Soft Robotics for Chemists Ilievski, Filip; Mazzeo, Aaron D; Shepherd, Robert F ...
Angewandte Chemie (International ed.),
February 18, 2011, Letnik:
50, Številka:
8
Journal Article
Recenzirano
Soft robots: A methodology based on embedded pneumatic networks (PneuNets) is described that enables large‐amplitude actuations in soft elastomers by pressurizing embedded channels. Examples include ...a structure that can change its curvature from convex to concave, and devices that act as compliant grippers for handling fragile objects (e.g., a chicken egg).
Multigait soft robot Shepherd, Robert F; Ilievski, Filip; Choi, Wonjae ...
Proceedings of the National Academy of Sciences - PNAS,
12/2011, Letnik:
108, Številka:
51
Journal Article
Recenzirano
Odprti dostop
This manuscript describes a unique class of locomotive robot: A soft robot, composed exclusively of soft materials (elastomeric polymers), which is inspired by animals (e.g., squid, starfish, worms) ...that do not have hard internal skeletons. Soft lithography was used to fabricate a pneumatically actuated robot capable of sophisticated locomotion (e.g., fluid movement of limbs and multiple gaits). This robot is quadrupedal; it uses no sensors, only five actuators, and a simple pneumatic valving system that operates at low pressures (< 10 psi). A combination of crawling and undulation gaits allowed this robot to navigate a difficult obstacle. This demonstration illustrates an advantage of soft robotics: They are systems in which simple types of actuation produce complex motion.
Three‐dimensional (3D) microperiodic scaffolds of poly(2‐hydroxyethyl methacrylate) (pHEMA) have been fabricated by direct‐write assembly of a photopolymerizable hydrogel ink. The ink is initially ...composed of physically entangled pHEMA chains dissolved in a solution of HEMA monomer, comonomer, photoinitiator and water. Upon printing 3D scaffolds of varying architecture, the ink filaments are exposed to UV light, where they are transformed into an interpenetrating hydrogel network of chemically cross‐linked and physically entangled pHEMA chains. These 3D microperiodic scaffolds are rendered growth compliant for primary rat hippocampal neurons by absorption of polylysine. Neuronal cells thrive on these scaffolds, forming differentiated, intricately branched networks. Confocal laser scanning microscopy reveals that both cell distribution and extent of neuronal process alignment depend upon scaffold architecture. This work provides an important step forward in the creation of suitable platforms for in vitro study of sensitive cell types.
3D microperiodic hydrogel scaffolds with varied architecture are patterned by direct‐write assembly and investigated as culture platforms for primary hippocampal neurons. Neuronal cells thrive on these scaffolds, forming differentiated, intricately branched networks. Confocal laser scanning microscopy reveals that both cell distribution and extent of neuronal process alignment depend upon scaffold architecture.
Camouflage and Display for Soft Machines Morin, Stephen A.; Shepherd, Robert F.; Kwok, Sen Wai ...
Science,
08/2012, Letnik:
337, Številka:
6096
Journal Article
Recenzirano
Odprti dostop
Synthetic systems cannot easily mimic the color-changing abilities of animals such as cephalopods. Soft machines—machines fabricated from soft polymers and flexible reinforcing sheets—are rapidly ...increasing in functionality. This manuscript describes simple microfluidic networks that can change the color, contrast, pattern, apparent shape, luminescence, and surface temperature of soft machines for camouflage and display. The color of these microfluidic networks can be changed simultaneously in the visible and infrared—a capability that organisms do not have. These strategies begin to imitate the functions, although not the anatomies, of color-changing animals.
A metal–elastomer‐foam composite that varies in stiffness, that can change shape and store shape memory, that self‐heals, and that welds into monolithic structures from smaller components is ...presented.