Octopuses are mysterious and frankly quite bizarre creatures. Invertebrates of the phylum Mollusca (molluscs) and the class Cephalopod, they are neurologically advanced aquatic animals which have existed since the Carboniferous era some 300 million years ago. And given that history, octopuses – and their close cousins the squid and the cuttlefish – have a long and noble lineage in our myth and legends. In Greek mythology, for instance, the Gorgon Medusa who was defeated by Perseus may have been inspired by an octopus. And the Ainu people (now assimilated Japanese) also celebrate Akkorokamui, an octopus-like creature who is thought to reside off the coast of the Japanese island of Hokkaido. The Kraken is a tentacled creature of popular maritime folklore which is said to attack ships and drown seafarers; while in the Hawaiian creation narrative, the octopus is a vestige of a preceding alien universe before our time.
And outside of mythology, these eight-armed sea-dwellers are no less interesting. Perhaps best known for their ability to shape-shift, easily changing the form, color, and texture of their skeleton-free bodies to blend into their environment, they possess additional qualities that render them unique within the animal kingdom. Their blood, for example, is copper-based – as opposed to our own iron-based blood – and so is blue not red. They also have not one but three hearts, two of which are devoted solely to moving blood from the gills with the third regulating circulation to the internal organs. And they are extremely intelligent creatures, solving puzzles, using tools, and engaging in play.
But it is their lack of skeletal rigidity, ability to move easily through tiny spaces, and the rubbery sensitivity of their limbs that has caught the eye of robotics researchers.
Robots are fairly commonplace in our 21st century society. They do innumerable jobs, handle repetitive tasks extremely well, are ideally suited to long working hours, precise movements, endless repetition, and less than ideal conditions. They neither complain nor unionize and are guaranteed to produce identical results almost 100% of the time. In myriad ways, they are absolutely ideal workers. The fundamentals of the science of robotics dates back to Norbert Wiener’s 1948 development of the principles of cybernetics which became the foundation of practical robotics. In the 1970s, the Selective Compliance Assembly Robot Arm (SCARA) was developed for use in assembly lines, grasping parts and equipment to transfer to other locations. Recognizing the breadth of their usefulness, industrial manufacturing has never looked back.
But conventional robots do have limitations. In fields outside of automotive engineering, construction, manufacturing, transportation, and assembly, the current generation of robots may not be the ideal tool for solving certain problems. Take, for example, fruit packing.
Peaches are a beloved fruit of the Carolinas and Georgia but their season is short – typically only sixteen weeks for Georgia peaches. And that foreshortened season puts pressure on workers to ship the product as fast as possible. At Titan Farms of South Carolina, for example, fruit is picked, sorted, packed, and shipped within 24-48 hours of harvest. And although this company’s technology includes automatic sizing and palletizing, photographic blemish detection, and automated PLU stickering, the routine work of hand-grading the peaches is a job that no robot can do.
But this is about to change.
With tactile sensitivity and delicate manual dexterity as required qualities not only for fruit pickers and packers but also in the bio-medical, pharmaceutical and optical fields, the development of soft robotics is underway. Although soft grippers, such as the SCHUNK cleanroom gripper which is activated by binary signals, already exist and are able to deploy adjustable force for assembly and laboratory testing, conventional hard robotic grippers are far more numerous in most workplace environments.(1) And the problem is that they can easily damage delicate items – precision optics, small components such as semiconductors, or fragile glass tools such as pipettes or dishes in a laboratory environment. And, having been developed for speed and strength, they are not adept at manipulating friable or non-standard items in an adaptive manner. Octobot, a soft robot created by a research team at Harvard University’s Wyss Institute, aims to fix that.
A fusion of 3D-printing and microfluidics, Octobot is an aesthetically pleasing device. At almost the size of a standard camera memory card and resembling an octopus, the largely see-through robot is 3D-printed on demand, made of non-rigid materials, and is powered by gas under pressure. As Michael Wehner, post-doctoral researcher on the team notes:
“This endeavor required us to rethink the way robots are designed from the bottom up. The soft robotics field has long desired to use hydrogen peroxide as a fuel, and pneumatic actuators are relatively common in soft robotics. Embarking on this project allowed us to embrace monopropellant fuel, pneumatic actuation, microfluidics, and combine them all using the novel embedded 3-D printing technology.”(2)
In other words, the Octobot is driven by an internal chemical reaction that causes a small amount of liquid hydrogen peroxide to convert to a larger volume of gas via a soft electronic oscillator. This gas then inflates bladders in the ‘arms’ of the robot so it can get to work. And while robots with adaptive soft grippers are already in use in fields such as undersea research, a robot with an entirely soft body will carve out its own unique niche. One of the most exciting uses of this kind of soft-bodied automaton would be within a sterile/contamination-controlled environment such as a cleanroom. As we know from previous articles published here in Contamination-Control News, the biggest source of potential contamination is the human operative within the sterile setting. Eliminate this source and we eliminate a huge amount of possible cross contamination.
Currently the Octobot is merely in the ‘proof-of-concept’ stage of development but the hope is that future versions will be able to swim, crawl, and interact intelligently with their environment. As it learns to adapt to more intellectually demanding tasks than simple gripping and placing, the Octobot may find itself mobilized in hospital operating rooms – retracting tissues, holding organs, stemming blood flow, or indeed completing surgery from within the patient’s body. Huge potential also exists for larger robots of this type in nursing facilities, aiding in the personal care of fragile seniors, and Octobot’s descendants may go on to become personal assistants to humans with mobility issues, perhaps even replacing guide dogs for visually impaired individuals. For, as Wehner noted in a piece in Qmed, a bio-medical device industry association, “In fields where a gentle touch is more important than a rigid grasp, we believe soft robots will emerge as the winner. […] One can easily envision soft robots being used to handle fragile objects such as […] living beings. Internal medicine and wearable devices are also likely areas for future soft robots.” (3)
Do you have thoughts about the future of soft robots? We would love to hear them!