When we imagine a robotwe think of a humanoid of metalto the robot that cleans a house or a mechanical arm of assembly chain. However, there are also other robots: more flexible, more adaptable and more “soft”. They are the soft robotmachines inspired by nature, designed to adapt to different types of environments. Are part of the bio-inspired roboticsa branch of robotics that observes the behavior of the living beings in their habitat to develop technologies capable of operating in similar environments. For example, to design robots that move underground, earthworms are studied; for the flying ones, the bees; For the transport of seeds, plants strategies. The solutions found in these fields often apply also outside the context for which they were born, in areas such as medicine or spatial exploration.
In this article we see what bio-inspired robots are and, in particular, the robots inspired by the octopusanimals that have offered fundamental ideas to design machines capable of explore the seabed marini, recover objects in extremely restricted spaces e grab elements of forms Very different among them.
What robots are and what is bio-inspired robotics
The robots are programmable machinescapable of carrying out homework automatically or remotely controlled. They are usually made up of three fundamental elements: sensors to perceive the environment (such as cameras or microphones); actuators to interact with the outside (engines, wheels, calipers); and acontrol unitthat is, the “brain” of the system, to process the data collected by the sensors and transmit orders to actuators.
Traditionally, robots have been used in controlled environments, such as assembly chains, where they can always repeat the same operations. But what happens if we have to work in a unstructured environmentwho changes and is changing, like the natural environment? To respond to this challenge, the Bio-inspired robotics: a field of scientific and technological research that takes inspiration from the natural world, in particular from living beingsto design robots and machines. The idea at the base is to observe how organisms behave – how they move, adapt, interact with the environment – and try to imitate these behaviors To create new technologies.
Robot with octopus tentacles: they are perfect for recovering objects of any form
The octopus is an extremely interesting animal for bio-inspired robotics. His body, completely without skeleton, is extremely flexible And it can deform to go through very close spaces. But it is not only soft: it can also selectively stiffen the limbs and apply great forces thanks to its muscle system. The eight tentacles are muscle hydrostatmuscle organs that do not need the support of any bone, such as the tongue human or the trunk of the elephant. They are made up of three types of muscle fibers – transversal, longitudinal and oblique – which, by combining, allow the tentacle to bend, stretch, shorten or twist in any direction. Replicating this ability is a big challenge for robotic engineering.
Another fundamental element are the windydistributed along the internal part of the tentacles. Each can generate one strong pressure negative (up to −65 kPa) allowing the octopus of adhere to irregular surfaces or viscide and grab objects with precision. The combination of strength, control and adaptability makes octopus an ideal source of inspiration for developing robots capable of operating in unstructured environments.
The robots inspired by octopus: from Octopus to Spirobs
In recent years several robots have been developed inspired by octopus, which try to imitate their biological characteristics. One of the pioneers in the field is Octopusa European project led by the Sant’Anna Superior School of Pisa. This robot has tentacles with the outside entirely in silicone, moved by metal springs that contract the passage of the current, and is capable of grasping objects with irregular shapes. His creation, more than 15 years ago, has started a series of more sophisticated projects.
https://www.youtube.com/watch?v=xn-bg8_aazm
For example, in Genoa, theIit (Italian Institute of Technology) has developed a Soft robotic arm designed to explore narrow environments, such as industrial pipes just 7 cm in diameter. This robot is made entirely of more or less soft silicones inside which metal cables are inserted. The Artificial windyinspired directly by those of the octopus, increase the grip force compared to systems without windy up to 12.5 times, allowing the recovery of objects in dirty, submerged or under pressure (up to 18 bar).
https://www.youtube.com/watch?v=upy_47_5gy
In 2020, researchers of the Harvard University and of the Beihang University they have further improved this system and presented a soft arm With biomimetic windy and an optimized tapered shape. The design of the suction cups, albeit simplified with respect to the biological model, allows the robot to adapt to objects of forms, dimensions and very different surfaces, from eggs to smartphones, and smooth surfaces, rough, flat or curves.
https://www.youtube.com/watch?v=8IXNCY4L_nc
Finally, in 2024 it was introduced Spirobsa new class of robot inspired by the logarithmic spiralcommon form also in the tentacles of the octopus. Spirobs, controlled via cables and entirely printed in 3D, can raise objects up to 260 times your weight. There are miniaturized versions, mounted on drones or with combinations of more arms to wrap and raise objects. The project is Open Source, That is, available and freely replicable, so that enthusiasts can print and recreate it at home.
