In the pursuit of humanoid robots, sometimes giving them wacky but believable facial expressions or a murderous sense of humor isn’t enough. Sometimes you have to give them indeed human skin.
Engineers at the University of Tokyo have found a way to glue human skin onto a robotic finger that almost feels like the real thing. In a paper published in the magazine on Thursday matter, the transplanted skin—a mashup of collagen, precursor skin cells, and skin cells that produce keratin—kept the animatronic finger water-resistant and, creepily enough, self-healing. It could be a big step toward building robots with living skin that’s just as functional, sensory, and responsive as our own.
The skin on most humanoid robots is made of silicone, which looks human enough but is unable to replicate the texture or function of real skin. Scientists have attempted to create living skin for our synthetic counterparts, but effectively draping biological materials around the harsh contours of a robotic body has been a difficult task.
“This method requires the hands of a skilled craftsman who can cut and tailor the skin layers,” said Shoji Takeuchi, a mechanical engineer at the University of Tokyo and co-author of the paper, in a press release. “To efficiently cover surfaces with skin cells, we developed a tissue molding process to mold skin tissues directly around the robot, resulting in seamless skin coverage on a robotic finger.”
This process involves dipping a three-pronged robotic finger into a pink solution eerily reminiscent of the western world Robots submerged in white liquid containers. The solution contains collagen, a protein that provides structural support to skin and other tissues in the body, and human dermal fibroblasts, cells that produce collagen and repair skin cells. Over the course of seven days, the collagen and fibroblasts adapt to the robotic finger, creating the innermost layer of skin, the dermis.
To create the epidermis – the outermost layer of skin – the finger was dipped in a solution containing human epidermal keratinocytes. These cells make up 90 percent of the epidermis and produce keratin, a protein that glues skin cells together and allows the epidermis to form a protective, waterproof barrier.
With its new skin, the motorized finger feels and looks almost like a real finger. Its epidermis was thick enough to pinch with tweezers and shed water. When the researchers cut it to simulate a wound, the finger’s living skin healed much like human skin, albeit with the help of a collagen foil, similar to a band-aid.
“The finger looks slightly ‘sweaty’ straight out of the culture medium,” Takeuchi said. “Since the finger is powered by an electric motor, it’s also interesting to hear the clicking sounds of the motor consistent with a real-looking finger.”
Unfortunately, since the skin is a living material, it cannot survive on the robotic finger for very long without a constant supply of nutrients and a method of waste disposal. Takeuchi and his team hope to fix this problem by creating channels under the dermis that could deliver water and nutrients like blood vessels in the human body do. They also want to create a version of artificial sweat glands that could help keep skin moist in dry environments. In the future, the team is looking at adding other features like hair follicles and nails to make the skin more lifelike, and integrating nerves that would allow a robot to sense and respond to its surroundings.
“I think living skin is the ultimate solution to give robots the look and feel of living things because it’s the exact same material that covers animal bodies,” Takeuchi said.
The look and touch of living creatures – it doesn’t get any more spooky in the valley.
https://www.thedailybeast.com/scientists-invent-self-healing-robot-skin?source=articles&via=rss Scientists invent self-healing robotic skin