NTU Singapore scientists develop 'mini-brains' to help robots recognize pain and to self-repair

October 15, 2020

Using a brain-inspired approach, scientists from Nanyang Technological University, Singapore (NTU Singapore) have developed a way for robots to have the artificial intelligence (AI) to recognise pain and to self-repair when damaged.

The system has AI-enabled sensor nodes to process and respond to 'pain' arising from pressure exerted by a physical force. The system also allows the robot to detect and repair its own damage when minorly 'injured', without the need for human intervention.

Currently, robots use a network of sensors to generate information about their immediate environment. For example, a disaster rescue robot uses camera and microphone sensors to locate a survivor under debris and then pulls the person out with guidance from touch sensors on their arms. A factory robot working on an assembly line uses vision to guide its arm to the right location and touch sensors to determine if the object is slipping when picked up.

Today's sensors typically do not process information but send it to a single large, powerful, central processing unit where learning occurs. As a result, existing robots are usually heavily wired which result in delayed response times. They are also susceptible to damage that will require maintenance and repair, which can be long and costly.

The new NTU approach embeds AI into the network of sensor nodes, connected to multiple small, less-powerful, processing units, that act like 'mini-brains' distributed on the robotic skin. This means learning happens locally and the wiring requirements and response time for the robot are reduced five to ten times compared to conventional robots, say the scientists.

Combining the system with a type of self-healing ion gel material means that the robots, when damaged, can recover their mechanical functions without human intervention.

The breakthrough research by the NTU scientists was published in the peer-reviewed scientific journal Nature Communications in August.

Co-lead author of the study, Associate Professor Arindam Basu from the School of Electrical & Electronic Engineering said, "For robots to work together with humans one day, one concern is how to ensure they will interact safely with us. For that reason, scientists around the world have been finding ways to bring a sense of awareness to robots, such as being able to 'feel' pain, to react to it, and to withstand harsh operating conditions. However, the complexity of putting together the multitude of sensors required and the resultant fragility of such a system is a major barrier for widespread adoption."

Assoc Prof Basu, who is a neuromorphic computing expert added, "Our work has demonstrated the feasibility of a robotic system that is capable of processing information efficiently with minimal wiring and circuits. By reducing the number of electronic components required, our system should become affordable and scalable. This will help accelerate the adoption of a new generation of robots in the marketplace."

Robust system enables 'injured' robot to self-repair

To teach the robot how to recognise pain and learn damaging stimuli, the research team fashioned memtransistors, which are 'brain-like' electronic devices capable of memory and information processing, as artificial pain receptors and synapses.

Through lab experiments, the research team demonstrated how the robot was able to learn to respond to injury in real time. They also showed that the robot continued to respond to pressure even after damage, proving the robustness of the system.

When 'injured' with a cut from a sharp object, the robot quickly loses mechanical function. But the molecules in the self-healing ion gel begin to interact, causing the robot to 'stitch' its 'wound' together and to restore its function while maintaining high responsiveness.

First author of the study, Rohit Abraham John, who is also a Research Fellow at the School of Materials Science & Engineering at NTU, said, "The self-healing properties of these novel devices help the robotic system to repeatedly stitch itself together when 'injured' with a cut or scratch, even at room temperature. This mimics how our biological system works, much like the way human skin heals on its own after a cut.

"In our tests, our robot can 'survive' and respond to unintentional mechanical damage arising from minor injuries such as scratches and bumps, while continuing to work effectively. If such a system were used with robots in real world settings, it could contribute to savings in maintenance."

Associate Professor Nripan Mathews, who is co-lead author and from the School of Materials Science & Engineering at NTU, said, "Conventional robots carry out tasks in a structured programmable manner, but ours can perceive their environment, learning and adapting behaviour accordingly. Most researchers focus on making more and more sensitive sensors, but do not focus on the challenges of how they can make decisions effectively. Such research is necessary for the next generation of robots to interact effectively with humans.

"In this work, our team has taken an approach that is off-the-beaten path, by applying new learning materials, devices and fabrication methods for robots to mimic the human neuro-biological functions. While still at a prototype stage, our findings have laid down important frameworks for the field, pointing the way forward for researchers to tackle these challenges."

Building on their previous body of work on neuromorphic electronics such as using light-activated devices to recognise objects, the NTU research team is now looking to collaborate with industry partners and government research labs to enhance their system for larger scale application.
-end-


Nanyang Technological University

Related Pain Articles from Brightsurf:

Pain researchers get a common language to describe pain
Pain researchers around the world have agreed to classify pain in the mouth, jaw and face according to the same system.

It's not just a pain in the head -- facial pain can be a symptom of headaches too
A new study finds that up to 10% of people with headaches also have facial pain.

New opioid speeds up recovery without increasing pain sensitivity or risk of chronic pain
A new type of non-addictive opioid developed by researchers at Tulane University and the Southeast Louisiana Veterans Health Care System accelerates recovery time from pain compared to morphine without increasing pain sensitivity, according to a new study published in the Journal of Neuroinflammation.

The insular cortex processes pain and drives learning from pain
Neuroscientists at EPFL have discovered an area of the brain, the insular cortex, that processes painful experiences and thereby drives learning from aversive events.

Pain, pain go away: new tools improve students' experience of school-based vaccines
Researchers at the University of Toronto and The Hospital for Sick Children (SickKids) have teamed up with educators, public health practitioners and grade seven students in Ontario to develop and implement a new approach to delivering school-based vaccines that improves student experience.

Pain sensitization increases risk of persistent knee pain
Becoming more sensitive to pain, or pain sensitization, is an important risk factor for developing persistent knee pain in osteoarthritis (OA), according to a new study by researchers from the Université de Montréal (UdeM) School of Rehabilitation and Hôpital Maisonneuve Rosemont Research Centre (CRHMR) in collaboration with researchers at Boston University School of Medicine (BUSM).

Becoming more sensitive to pain increases the risk of knee pain not going away
A new study by researchers in Montreal and Boston looks at the role that pain plays in osteoarthritis, a disease that affects over 300 million adults worldwide.

Pain disruption therapy treats source of chronic back pain
People with treatment-resistant back pain may get significant and lasting relief with dorsal root ganglion (DRG) stimulation therapy, an innovative treatment that short-circuits pain, suggests a study presented at the ANESTHESIOLOGY® 2018 annual meeting.

Sugar pills relieve pain for chronic pain patients
Someday doctors may prescribe sugar pills for certain chronic pain patients based on their brain anatomy and psychology.

Peripheral nerve block provides some with long-lasting pain relief for severe facial pain
A new study has shown that use of peripheral nerve blocks in the treatment of Trigeminal Neuralgia (TGN) may produce long-term pain relief.

Read More: Pain News and Pain Current Events
Brightsurf.com is a participant in the Amazon Services LLC Associates Program, an affiliate advertising program designed to provide a means for sites to earn advertising fees by advertising and linking to Amazon.com.