University of Tokyo researchers created a robotic finger that's covered in living human skin cells. Demo below. The technique involves soaking the robotic finger in a solution of collagen and human dermal fibroblasts, two key ingredients in skin's connective tissue. The final coat is human epidermal keratinocytes, the major cell type of skin's outer layer.
From Cell Press:
When wounded, the crafted skin could even self-heal like humans' with the help of a collagen bandage, which gradually morphed into the skin and withstood repeated joint movements.
"We are surprised by how well the skin tissue conforms to the robot's surface," says Takeuchi. "But this work is just the first step toward creating robots covered with living skin." The developed skin is much weaker than natural skin and can't survive long without constant nutrient supply and waste removal. Next, Takeuchi and his team plan to address those issues and incorporate more sophisticated functional structures within the skin, such as sensory neurons, hair follicles, nails, and sweat glands.