Summary: Researchers have developed a controllable robotic finger covered with living skin tissue that has the ability to heal itself.
Source: University of Tokyo
Researchers from the University of Tokyo pool knowledge of robotics and tissue culturing to create a controllable robotic finger covered with living skin tissue.
The robotic digit had living cells and supporting organic material grown on top of it for ideal shaping and strength. As the skin is soft and can even heal itself, so could be useful in applications that require a gentle touch but also robustness.
The team aims to add other kinds of cells into future iterations, giving devices the ability to sense as we do.
Professor Shoji Takeuchi is a pioneer in the field of biohybrid robots, the intersection of robotics and bioengineering. Together with researchers from around the University of Tokyo, he explores things such as artificial muscles, synthetic odor receptors, lab-grown meat, and more. His most recent creation is both inspired by and aims to aid medical research on skin damage such as deep wounds and burns, as well as help advance manufacturing.
“We have created a working robotic finger that articulates just as ours does, and is covered by a kind of artificial skin that can heal itself,” said Takeuchi.
“Our skin model is a complex three-dimensional matrix that is grown in situ on the finger itself. It is not grown separately then cut to size and adhered to the device; our method provides a more complete covering and is more strongly anchored too.”
Three-dimensional skin models have been used for some time for cosmetic and drug research and testing, but this is the first time such materials have been used on a working robot. In this case, the synthetic skin is made from a lightweight collagen matrix known as a hydrogel, within which several kinds of living skin cells called fibroblasts and keratinocytes are grown.
The skin is grown directly on the robotic component which proved to be one of the more challenging aspects of this research, requiring specially engineered structures that can anchor the collagen matrix to them, but it was worth it for the aforementioned benefits.
“Our creation is not only soft like real skin but can repair itself if cut or damaged in some way. So we imagine it could be useful in industries where in situ repairability is important as are humanlike qualities, such as dexterity and a light touch,” said Takeuchi.
“In the future, we will develop more advanced versions by reproducing some of the organs found in skin, such as sensory cells, hair follicles and sweat glands. Also, we would like to try to coat larger structures.”
The main long-term aim for this research is to open up new possibilities in advanced manufacturing industries. Having humanlike manipulators could allow for the automation of things currently only achievable by highly skilled professionals.
Other areas such as cosmetics, pharmaceuticals and regenerative medicine could also benefit. This could potentially reduce cost, time and complexity of research in these areas and could even reduce the need for animal testing.
Funding: JSPS Grants-in-Aid for Scientific (KAKENHI), Grant Numbers 16H06329, 21H00321, 21H05013 and 19H04508. JSPS Grant-in-Aid for Early-Career Scientists (KAKENHI), Grant Number 19K15415.
The method for generating seamless coverage of 3D objects with skin equivalent
Three-joint robotic finger covered with living skin equivalent
Wound repair of a robotic finger covered with dermis equivalent
Progress and potential
The covering materials of humanoid robots have gone through transformations from stiff and heavy materials to soft and compliant materials to better mimic the appearance and function of human beings.
Here, we report a biohybrid approach to generate robots covered with tissue-engineered skin.
The skin coverage not only results in a human-like appearance but also enables self-healing functions. We demonstrate the seamless coverage of a three-joint robotic finger by culturing a single piece of skin tissue surrounding the robotic finger.
Furthermore, inspired by the medical treatment of deeply burned skin using grafted hydrogels, we demonstrate wound repair of a dermis equivalent covering a robotic finger by culturing the wounded tissue grafted with a collagen sheet.
Taken together, these findings show the potential of a paradigm shift from traditional robotics to the new scheme of biohybrid robotics that leverage the advantages of both living materials and artificial materials.
Humanoids are robots created with human forms or characteristics; these robots also have the potential to seamlessly interact with human beings. By replicating the appearances and functions (e.g., self-healing) of human beings, humanoids have the potential to establish more harmonic and natural human-robot interactions.
Here, we propose the use of skin equivalent, a living skin model consisting of cells and extracellular matrix, as a human-like and self-healing coverage material for robots.
We fabricated a three-joint robotic finger covered with skin equivalent by developing a method to cover three-dimensional objects with skin equivalent.
Furthermore, inspired by the medical treatment of deeply burned skin using grafted hydrogels, we demonstrated wound repair of a dermis equivalent covering a robotic finger by culturing the wounded tissue grafted with a collagen sheet.
With the above results, this research shows the potential of using skin equivalent as human-like and self-healing coverage material for robots.