Scientists in Hong Kong have developed artificial skin that bruises like the real thing.
The material, called I-skin, could be used on artificial limbs to alert users they have damaged their prosthetics.
It’s embedded with a gel that turns from yellow to welt-like purple when subjected to physical stress.
Volunteers wearing strips of I-skin on their fingers, hands and knees repeatedly banged the appendage against a wall, proving the ‘bruise’ would appear if enough force was used.
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Scientists in Hong Kong have developed an artificial skin that will mimic the discoloration of a bruise if hit hard enough. Volunteers wearing strips of I-skin on their fingers, hands and knees repeatedly banged the appendage against a wall, proving a ‘bruise’ would appear if enough force was used
‘Artificial skins with sensing ability have great potential in applications of wearable devices and soft robotics,’ researchers at the Chinese University of Hong Kong wrote in a new report published in the journal ACS Applied Materials & Interfaces.
To develop a material that mimicked human bruises, engineer Wenlian Qiu and her team developed an ionic hydrogel infused with spiropyran, a molecule that approximates the blue-purple shade of a bruise when subjected to ‘a large deformation,’ according to their report.
I-skin can be bent and stretched without discoloring, New Atlas reported, though this did affect its electrical signals.
But repeated or forceful hitting, pinching or pressing brings an eggplant hue to the surface, as evidenced in a recent video.
The ionic hydrogel in the I-skin (right) mimics the plum coloration of a real bruise for two to five hours before returning to its default yellow coloring
The discoloration remains visible for between two to five hours, the researchers said.
In addition to prosthetics, the technology could also be used on wearable electronics or even robots, to indicate damage or simply make them more ‘lifelike.’
Engineers are increasingly working on artificial epidermis that doesn’t just simulate the look of real skin, but reacts like it, too—in use with prosthetic limbs and for robots expected to socialize with humans.
I-skin can be bent and stretched without discoloring. But hitting, pinching or pressing with sufficient force brings an eggplant hue to the surface
In September, scientists at RMIT University in Australia announced they had developed a material that can ‘feel pain’ in the same way as the real-life organ.
Their breakthrough pseudo-skin, reported in the journal Advanced Intelligent Systems, replicates human nerves with electrical signals to trigger an immediate reaction.
‘Skin is our body’s largest sensory organ, with complex features designed to send rapid-fire warning signals when anything hurts,’ lead researcher Madhu Bhaskaran said in a statement.
‘We’re sensing things all the time through the skin but our pain response only kicks in at a certain point, like when we touch something too hot or too sharp.
‘No electronic technologies have been able to realistically mimic that very human feeling of pain – until now.
‘Our artificial skin reacts instantly when pressure, heat or cold reach a painful threshold.’
The skin-like sensing prototype device devised by scientists at RMIT University in Melbourne, Australia, ‘reacts instantly when pressure, heat or cold reach a painful threshold,’ researchers say
Research fellow Md. Ataur Rahman added that while some existing technology uses electrical signals to mimic pain, ‘our artificial skin knows the difference between gently touching a pin with your finger or accidentally stabbing yourself with it – a critical distinction that has never been achieved before electronically.’
Also in November, scientists at Saudi Arabia’s King Abdullah University of Science and Technology unveiled a different synthetic skin can sense atmospheric changes from a distance and repair itself more than 5,000 times.
A durable e-skin developed at King Abdullah University of Science is strong enough to be stretched and twisted but sensitive enough to ‘read’ handwriting written on its surface
According to research published in the journal Science Advances, the team used a hydrogel reinforced with silica nanoparticles to create a ‘stretchy surface’ and combined it with a 2D titanium carbide MXene sensor using highly conductive nano wires.
Their prototype e-skin is reportedly so highly sensitive it can sense objects from eight inches away, distinguish handwriting written on its surface and and respond to stimuli in under a tenth of a second.
‘It is a striking achievement for an e-skin to maintain toughness after repeated use, which mimics the elasticity and rapid recovery of human skin,’ co-author Jie Shen said in a release from the university.
HOW HAVE SCIENTISTS CREATED SKIN THAT REPAIRS ITSELF?
Cutting your hand, tearing a muscle, or even breaking a bone are all injuries that will heal over time.
Experts at Vrije Universiteit Brussels (VUB) have created a synthetic skin that aims to mimic nature’s self-repairing abilities, allowing robots to recover from ‘wounds’ sustained while undertaking their duties.
Further development of the technology could also allow Terminator-style killer robots, built for the battlefield, to repair the damage they sustain in combat.
Researchers have been with experimenting with soft robots for some time now.
They are constructed from flexible materials, inspired by the soft tissue from which humans and many other organisms are made.
Their flexibility allows them to be used for a wide variety of applications, from grabbing delicate and soft objects in the food industry to performing minimally invasive surgery.
They could also play an important role in creating lifelike prosthetics.
However, the soft materials also make them susceptible to damage from sharp objects or excessive pressure.
Damaged components must then be replaced to avoid the robot ending up on the scrap heap.
But VUB has come up with a new rubber polymer that can repair this type of damage.
Professor Bram Vanderborght of BruBotics VUB, who worked on the plastic, said: ‘The outcome of the research opens up promising perspectives.
‘Robots can not only be made lighter and safer, they will also be able to work longer independently without requiring constant repairs.’
To create their synthetic flesh, the scientists used jelly-like polymers that melt into each together when heated and then cooled.
When damaged, these materials first recover their original shape and then heal completely.
This principle was applied in three self-healing robotic components; a gripper, a robot hand, and an artificial muscle.
These resilient, pneumatic components were damaged under controlled conditions to test whether the scientific principle also works in practice