Robotic Arm that feels touch like actual skin

September 25, 2018

Written by:

 

Robots of the future could learn to grasp and pick up delicate objects thanks to a new material inspired by human skin.  

 

Experts have built a tactile sensor that detects pressure and sends out an electric pulse in response to touch.

As well as its applications for intelligent machines, the breakthrough could lead to prosthetic limbs that let people with disabilities feel again.

 

HOW DOES IT WORK?

The skin encases a magnetic sensor and is composed of a hollow polymer membrane with magnetic particles on its top surface. 

 

When pressure is applied to the magnet-dotted membrane roof, the membrane inverts, causing the magnetic particles on the top to inch toward the magnetic sensor on the inside. 

 

The resulting resistance created is transmitted as signals using an electrical circuit, and these signals are converted as pulses with various frequencies that increased with greater pressure. 

 

Mounted on a mechanical arm, an artificial finger equipped with the e-skin was able to perceive the subtlest touches, such as the wind blowing.

 

In subsequent experiments, the e-skin was also able to detect and pulse in response to drops of water that contained different volumes, as well as a moving trail of ants. 

 

 

A research team, including members of the faculty at the Chinese Academy of Sciences, have been working on replicating the experience of pressurised human touch.

 

The technology may represent a critical step forward in the development of smart prosthetics that can functionally replace – or potentially even surpass – the sensing ability of natural limbs, the researchers say. 

 

Human skin perceives pressure as part of touch, which is then transformed into signals to nerves that finally reach the brain, creating a pulse-like feeling.

 

Restoring this sense of pressurised touch remains an important feature needed to make artificial limbs more life-like and thus more acceptable for their users.  

 

Yuanzhao Wu and colleagues developed an e-skin system that can convert pressure from touch to internal electric signals.

 

Interestingly, in some cases, the pulses responded to pressures exceeding the sensing threshold value of humans.

 

Writing in a paper outlining their findings, its authors said: 'Overall, the performance of the reported tactile sensor indicates potential applications in the field of smart prosthetics. 

 

'Sensory feedback of tactile sensors with high sensitivity, low detection limit, and digital frequency signals may make prosthetic limbs better and more personalized in the future.'

 

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.

 

The skin encases a magnetic sensor and is composed of a hollow polymer membrane with magnetic particles on its top surface. 

 

When pressure is applied to the magnet-dotted membrane roof, the membrane inverts, causing the magnetic particles on the top to inch toward the magnetic sensor on the inside. 

 

The resulting resistance created is transmitted as signals using an electrical circuit, and these signals are converted as pulses with various frequencies that increased with greater pressure. 

 

Mounted on a mechanical arm, an artificial finger equipped with the e-skin was able to perceive the subtlest touches, such as the wind blowing.

 

In subsequent experiments, the e-skin was also able to detect and pulse in response to drops of water that contained different volumes, as well as a moving trail of ants

 

 

HOW DO MIND CONTROLLED PROSTHETICS WORK?

Prosthetics that attach to part of the human body are often objects that allow a person to perform a specific function - such as blades for running.

 

Scientists are working to develop prosthetics that are personalised and respond to the commands of the wearer.

 

To do this, small pads are placed on the skin of the patient.

 

They are located around the end of muscles and where the nerve endings begin. 

 

The pads detect the electrical signals that are produced by the muscle nerves and translate this via a computer. 

 

To trigger these sensors, the patient must actively think about performing an action. 

 

For example, in order to signal a bicep contraction, the person wearing the prosthetic would have to think about bending their arm. 

 

By understanding what muscles are being signalled by the brain to contract, scientists can predict how a limb would move. 

 

This is then recreated by the prosthetic in real-time, allowing wearers to think an action and then the artificial limb will perform it.  

 

DAILYMAIL

Share on Facebook
Share on Twitter
Please reload

Featured Posts

Black-Owned Investment Firm Gets Green Light on $700M Redevelopment Project for South Central L.A. Plaza

November 3, 2017

1/4
Please reload

Recent Posts
Please reload

Archive