The call soft robotics tries to imitate the actions of living organisms, such as moving or perceiving the environment, using flexible and adjustable materials capable of adapting to the environment efficiently.
Scientists have been developing biohybrid robots or biobots, usually made up of muscle tissue (cardiac or skeletal) and an artificial skeleton, which can crawl, cling, or swim. The problem is that they do not reach the mobility and strength of a living being.
These little over 1cm biobots, which can swim and glide like fish at unprecedented speeds, have been created with a flexible 3D printed skeleton and a hydrogel with muscle cells
Now researchers from the Institute of Bioengineering of Catalonia (IBEC) They have overcome those two challenges by developing new biobots, just over a centimeter long, that can swim and glide like fish at unprecedented speeds.
The breakthrough, published in the journal Science Robotics, has been achieved by adding bioengineering tools and knowledge of animal physiology: an innovative flexible skeleton that is 3D printed and spontaneous contraction of muscle cell-based materials.
“The biobots we have designed are made up of muscle cells that move like worms or fish, react to electrical stimuli and exert surprising forces and speeds thanks to their self-training with the flexible 3D printed skeleton,” he explains. Samuel Sanchez, ICREA professor who leads this research.
While most scientists usually work with rigid or anchored skeletons to prepare artificial robots, the IBEC researchers used biological robots based on a flexible coil-shaped spring made of the polymer polydimethylsiloxane (PDMS). It was first designed and optimized using simulations and then generated with the 3D printer.
The advantage of this innovative skeleton lies in the improvement of training and tissue development through mechanical self-stimulation over spontaneous contractions, which creates a feedback loop due to the restoring force of the spring.
This phenomenon of self training allows for improved performance and greater contraction force of the biobot. These skeletons had not been included in a living soft robotics system before.
Our biobots are the fastest swimming biohydride robots to date, increasing their speed by 791 times (compared to others with muscle cells)
Maria Guix (IBEC)
“The greater strength, the result of the design that allows self-training, has made our biobots the fastest swimming biohydride robots to date, increasing their speed by 791 times (compared to others with muscle cells),” he says. Maria guix, IBEC researcher and first author of the article. They are comparable to other biological swimmers based on cardiomyocytes (heart cells).
But this new generation of biobots can also perform other movements: they are able to glide when placed near the surface of the aquatic bottom, resembling the swimming style of certain fish near surfaces, such as the intermittent burst behavior of zebrafish, characterized by sporadic movements followed by phases of inertia.
Environmental and biomedical applications
According to its authors, this work opens the doors to a new generation of stronger and faster biological robots based on muscle cells, with potential applications both for environmental and drug delivery purposes and for the development of bionic prostheses.
In the biomedical field, this technology could also be applied to print 3D models with human muscles, generating bioplatforms to test drugs.
Rights: Creative Commons.