Soft robotics: a bioinspired evolution in robotics

doi:10.1016/j.tibtech.2013.03.002

Trends in Biotechnology

Volume 31, Issue 5, May 2013, Pages 287-294

https://doi.org/10.1016/j.tibtech.2013.03.002 Get rights and content

Highlights

•
The paper reviews a recent development in soft robotics.
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Soft materials in animals inspire a new wave of robotics.
•
Current enabling technologies in soft robotics and challenges are discussed.
•
Potential convergence between soft robotics and tissue engineering is introduced.

Animals exploit soft structures to move effectively in complex natural environments. These capabilities have inspired robotic engineers to incorporate soft technologies into their designs. The goal is to endow robots with new, bioinspired capabilities that permit adaptive, flexible interactions with unpredictable environments. Here, we review emerging soft-bodied robotic systems, and in particular recent developments inspired by soft-bodied animals. Incorporating soft technologies can potentially reduce the mechanical and algorithmic complexity involved in robot design. Incorporating soft technologies will also expedite the evolution of robots that can safely interact with humans and natural environments. Finally, soft robotics technology can be combined with tissue engineering to create hybrid systems for medical applications.

Section snippets

Soft biological materials inspire a new wave of robotics

Human-made manufacturing robots are mostly designed to be stiff so that they can perform fast, precise, strong, and repetitive position control tasks in assembly lines. Common actuators in such robotic systems are composed of rigid electromagnetic components (e.g., magnets, copper, and steel bearings) or internal combustion engines made of steel and aluminum alloys. By contrast, in the animal world soft materials prevail. The vast majority of animals are soft bodied, and even animals with stiff

Soft-bodied animals and soft-bodied robots

One problem with developing robots that use soft materials is that we currently have no general theory of how to control such unconstrained structures. Robotics engineers have begun to develop this knowledge by building robot models based on the neuromechanical strategies that soft-bodied animals use to locomote, chiefly annelids (earthworms and leeches)[6], molluscs (primarily the octopus)[7], and insect larvae (caterpillars) [8].

Actuation

One of the biggest challenges in soft robotics is designing flexible actuation systems capable of high forces, to replicate the functionality of muscles in the animal body. The ability of soft animals to change body shape depends on a large number of muscles being distributed over the body. Currently there are three popular actuation techniques.

The first technique is to use dielectric elastomeric actuators (DEAs) made of soft materials that actuate through electrostatic forces – an important

Future convergence with tissue engineering

Soft materials open up new prospects for bioengineered and biohybrid devices [64]. Researchers have created a flexible biohybrid microsystem that models the alveolus–capillary interface of the human lung [65]. A soft material allows the interface to be rhythmically stretched, reproducing the cyclical mechanical effects of breathing. By growing cardiac muscle cells, researchers have developed a tissue-engineered jellyfish that can swim [66]. Significant advances have been made in developing

Concluding remarks

Recent work on soft technologies embodied in robotic systems has been greatly inspired by the study of soft-bodied animals. The investigation of biological examples is playing a vital role in developing new robotic mechanisms, actuation techniques, and algorithms. To construct robots that implement the biomechanical intelligence of soft-bodied animals, we need new active soft materials. Developing soft muscle-like actuation technology is still one of the major challenges in the creation of

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Trends in Biotechnology

ReviewSoft robotics: a bioinspired evolution in robotics

Highlights

Section snippets

Soft biological materials inspire a new wave of robotics

Soft-bodied animals and soft-bodied robots

Actuation

Future convergence with tissue engineering

Concluding remarks

Curr. Biol.

J. Neurosci. Methods

Curr. Biol.

Mater. Sci. Eng. C

Sens. Actuators B: Chem.

Int. J. Nonlin. Mech.

J. Mech. Phys. Solids

Mater. Lett.

Adv. Drug Deliv. Rev.

Biomaterials

New robotics: design principles for intelligent systems

Artif. Life

Soft robotics: biological inspiration, state of the art, and future research

Appl. Bionics Biomech.

Soft robotics: from torque feedback controlled lightweight robots to intrinsically compliant systems

IEEE Robot. Autom. Mag.

Tongues, tentacles and trunks – the biomechanics of movement in muscular-hydrostats

Zool. J. Linn. Soc.

Carnivorous caterpillars: the behavior, biogeography and conservation of Eupithecia (Lepidoptera: Geometridae) in the Hawaiian Islands

GeoJournal

Peristaltic locomotion with antagonistic actuators in soft robotics

A soft robot arm inspired by the octopus

Adv. Robot.

GoQBot: a caterpillar-inspired soft-bodied rolling robot

Bioinspir. Biomim.

Ontogenetic scaling of hydrostatic skeletons: geometric, static stress and dynamic stress scaling of the earthworm Lumbricus terrestris

J. Exp. Biol.

Kinematic scaling of locomotion by hydrostatic animals: ontogeny of peristaltic crawling by the earthworm Lumbricus terrestris

J. Exp. Biol.

The Locomotion of Soft-bodied Animals

Development of a peristaltic endoscope

Artificial annelid robot driven by soft actuators

Bioinspir. Biomim.

A SMA actuated artificial earthworm

Shape memory alloy-based small crawling robots inspired by C. elegans

Bioinspir. Biomim.

Ontogenetic scaling of caterpillar body properties and its biomechanical implications on the use of hydrostatic skeletons

J. Exp. Biol.

The biomechanical and neural control of hydrostatic limb movements in Manduca sexta

J. Exp. Biol.

The substrate as a skeleton: ground reaction forces from a soft-bodied legged animal

J. Exp. Biol.

Caterpillars use the substrate as their external skeleton: A behavior confirmation

Commun. Integr. Biol.

Motor patterns associated with crawling in a soft-bodied arthropod

J. Exp. Biol.

Kinematics of soft-bodied, legged locomotion in Manduca sexta larvae

Biol. Bull.

Modeling locomotion of a soft-bodied arthropod using inverse dynamics

Bioinspir. Biomim.

Context dependency of a limb withdrawal reflex in the caterpillar Manduca sexta

J. Comp. Physiol. A

Combined kinematic and electromyographic analyses of proleg function during crawling by the caterpillar Manduca sexta

J. Comp. Physiol. A

Dendritic reorganization of abdominal motoneurons during metamorphosis of the moth, Manduca sexta

J. Neurosci.

Review
Soft robotics: a bioinspired evolution in robotics