Engineers in Japan are trying to make robots imitate that very human expression: the smile.
They’ve made a face mask from human skin cells and attached it to robots with a new technique that hides the bond and is flexible enough to go down in a grimace or up in a soft smile.
The effect is a cross between Hannibal Lecter’s terrifying mask and the Claymation figure Gumby.
But scientists say the prototypes pave the way for more advanced robots, with an outer layer that is both elastic and durable enough to protect the machine while making it appear more human.
In addition to expressiveness, the “skin equivalent,” as the researchers call it, which is made in a laboratory from living skin cells, can cause scars and burns and also heal itself, the researchers said. a study published on June 25 in the journal Cell Reports Physical Science.
“Human-like faces and expressions improve communication and empathy in human-robot interactions, making robots more effective in healthcare, service delivery and companion roles,” said Shoji Takeuchi, a professor at the University of Tokyo and lead researcher on the study, in an e -mail.
The research comes as robots become more ubiquitous on factory floors.
There were 3.9 million industrial robots working on automotive and electronics assembly lines and other work environments by 2022, according to the International Federation of Robotics.
A subset of the overall robot population includes so-called humanoids, machines designed with two arms and two legs that allow them to work in environments built for human workers, such as factories, as well as in hospitality, healthcare and education.
Carsten Heer, a spokesman for the federation, said humanoids were “an exciting area of development” but mass-market adoption would be complex and could be limited by costs.
Still, the Chinese government announced a target in October 2023 mass-producing humanoids by 2025, which was predicted to significantly increase industrial productivity.
For decades, robotics engineers have experimented with materials, hoping to find something that could both protect a robot’s complex machinery and be soft and light enough for a wide range of applications.
Scratches or scratches on a robot’s surface can lead to machine failure, making the ability to self-repair a “critical feature” for humanoid robots, the researchers said in the paper.
The new skin attachment method advances the emerging field of “biohybrid” robotics, which integrates mechanical engineering with genetic and tissue engineering, says Kevin Lynch, director of the Center for Robotics and Biosystems at Northwestern University.
“This study is an innovative contribution to the problem of anchoring artificial skin to the underlying material,” said Professor Lynch, adding that “living skin could help us achieve the holy grail of self-healing skins in biohybrid robots.”
He added that the study does not address how the robots’ skin will heal itself without external support.
For such robots, the materials challenge extends to verisimilitude: finding ways to imbue the machine with features that make it look and behave more like a human, such as the ability to smile.
Scientists, including Professor Takeuchi and his colleagues from the University of Tokyo, have been working with laboratory-made human skin for years.
In 2022, the research team developed a robotic finger covered in living skin, allowing the machine’s finger to bend like a human finger, giving it the tactility to perform potentially more precise tasks.
Professor Takeuchi’s team had tried to anchor the skin with mini hooks, but they caused tears as the robot moved. So the team decided to mimic ligaments, the small strings of loose tissue that connect bones.
Team members drilled small, V-shaped holes in the robot and applied a gel containing collagen, which closed the holes and secured the artificial skin to the robot.
“This approach integrates traditional rigid robots with soft, biological skins, making them more ‘human-like,’” said Yifan Wang, assistant professor at the School of Mechanical and Aerospace Engineering at Nanyang Technological University in Singapore, who researches “soft robots’ those biological beings.
The skin bond also gives a biohybrid robot the potential for sensation, bringing science one step closer to science fiction fantasy.
“This could create opportunities for the robot to detect people and communicate with them safely,” said Professor Wang.
The faces of the artificial-skinned robots in Professor Takeuchi’s laboratory do not have the ability to sense touch, temperature change or other external stimuli.
Professor Takeuchi said this is his next research goal.
“We aim to create skin that closely mimics the functionality of real skin by gradually creating essential components such as blood vessels, nerves, sweat glands, sebaceous glands and hair follicles,” he said.
Instead of the neural systems that transmit sensation in a human body, a robot’s electronics would have to control a sensor signal – a development that Professor Wang says would take much more time and research.
