Graphical Abstract
(Photo : Cell.com) Image shows the fixation through perforation-type anchors allows gently tugging on the skin.

In a major leap forward for robotics, scientists have created a self-healing “living skin” that could give robots the appearance of being more human and less mechanical. This ground-breaking approach involves using cultured skin cells and new ways of attaching them, which may enable future robots to be wrapped in realistic, self-regenerating skins.

The results were published on June 25th in Cell Reports Physical Science, revealing that this artificial skin looks like human skin and can heal itself from minor damage.

Transformational Adhesive Technique Boosts Beauty

Artificial skins have been considered an enabler for making robots look more like humans. Previously done methods of sticking artificial skin involved having “anchors”, i.e., hooked or mushroom-shaped structures which would end up causing embarrassing lumps under the skin. The latest research introduces a novel solution—perforation-type anchors – tiny v-shaped hooks that go into the robot’s skeleton. Doing so ensures that the attachment process occurs smoothly and flexibly without hampering its external appearance.

The new skin is layered over a robot and treated with water-vapor plasma to make the surface hydrophilic, hence allowing better adherence of gel from cultured skin. This innovative method prevents sagging or detachment – common problems with older designs.

Conceptual illustration of the tissue-fixation method using perforation-type anchor
Conceptual illustration of the tissue-fixation method using perforation-type anchor (A) Conceptual illustration of a perforation-type anchor inspired by skin ligaments to cover robots with skin equivalents. (B) Process of the tissue fixation using perforation-type anchors.
(Photo : Cell.com)

Self-Healing Ability and Enhanced endurance

One remarkable feature of this new type of skin is its ability to autonomously heal small tears or damages autonomously, reducing the cost of manual repairs and increasing its lifespan. This capability does not mention how fast injuries can heal; however, it marks significant advancements in robotic skins.

Results demonstrated during testing showed that artificial skins with perforation anchors only contracted by 33.6% after seven days compared to those without anchors at 84.5%. Enlarged anchors had even better results, with 26.4% and 32.2% skin contraction rates for the 0.1-inch (3mm) and 0.2-inch (5mm) anchors, respectively.

Future Prospects and Challenges

Shoji Takeuchi, one of the lead researchers in the study from the Institute of Industrial Science at the University of Tokyo, talked about several hurdles to overcome before this technology can become extensively applicable. For instance, to improve the durability of cultured skin, the need for stable nutrition supply and moisture, as well as integrated perfusion systems, must be developed. Furthermore, the mechanical strength of the skin should be increased up to that observed in natural human skin.

Takeuchi also included sensory functions like temperature and touch and biofouling resistance, among other issues artificial skin should address. This improvement may increase robotic device functionality and provide insight into facial muscle actions useful to fields such as cosmetic surgery and orthopedics.

What's Next?

However, further research is required to fully exploit the implications behind this innovative self-healing robotic skin discovery. With advancing technology, robots could soon possess more lifelike skins, both in the appearance of humans’ external organs and in their operational characteristics. This combination is set to change how robots interact with people by using silicone together with cultured cells, thus bringing us closer than ever before to making machines that can smile or simply express emotions like us.