A new robot developed by MIT in the US is being used to kill coronavirus in a 4,000-square-foot warehouse using ultraviolet light (UV) light.
The autonomous machine uses a specific type of short-wavelength UV, known as UVC, to kill microorganisms and disrupt their DNA in a process known as ‘ultraviolet germicidal irradiation’.
UVC is emitted from the bot’s four vertical beams as it nips around warehouse aisles, killing 90 per cent of coronavirus particles in 30 minutes.
Because UVC light is harmful to humans, the robot has to do its work alone and is sent to do its sanitising shift when human workers have clocked off.
The robot can map an entire industrial facility – in this case the Great Boston Food Bank (GBFB), a US non-profit that provides hunger relief.
Food banks face a particular demand due to the stress of Covid-19, which has killed more than half a million people worldwide.
The UN predicted the number of people facing severe food insecurity could double to reach 265 million because of coronavirus.
This means it is vital that hunger relief packages distributed in the US are free from the pathogen.
‘Food banks provide an essential service to our communities, so it is critical to help keep these operations running,’ said Alyssa Pierson, research scientist at MIT’s Computer Science & Artificial Intelligence Lab in Cambridge, Massachusetts, US.
‘Here, there was a unique opportunity to provide additional disinfecting power to their current workflow, and help reduce the risks of Covid-19 exposure.’
MIT said surfaces are generous hosts for SARS-CoV-2, the coronavirus that causes Covid-19, as well as other harmful pathogens.
Chemical cleaning products are effective, but using them to disinfect a wide area can take a lot of time and can put a human worker at risk of being infected.
They therefore turned to UVC, which is already being used to sanitise hospital equipment, and robotics technology so it can be operated without human workers.
The autonomous bot scoots around the warehouse with four vertical bars that emit UV light, which are mounted on a base from Massachusetts firm Ava Robotics.
During tests at the GBFB facility, the robot drove by pallets and storage aisles at a speed of around 0.22 miles per hour.
At this speed, the UV light neutralises at least 90 per cent of microorganisms on the various types of surfaces at the facility.
The system can disinfect GBFB’s warehouse floor in half an hour, but it could also be employed in supermarkets, factories, restaurants and schools.
The robot is initially teleoperated by a remote user, who teaches the robot’s path around the warehouse, but it can subsequently operate autonomously.
It can go to defined waypoints on its map, such as the loading dock and the shipping floor, before returning to base.
These waypoints are defined by the human user in the initial teleoperated mode, who can add new waypoints to the map as needed.
Each day at the GBFB facility, workers pass through the aisles and gather products for up to 50 pick-ups by partners and distribution trucks the next day.
By focusing on the shipping area, it prioritises disinfecting items leaving the warehouse to reduce the virus from spreading out into the community with the relief packages.
While it’s most effective in the direct line of slight, the UVC rays can get to nooks and crannies as the light bounces off surfaces and onto other surfaces, and can also work against airborne pathogens.
The team at MIT are exploring how to use its on-board sensors to adapt to changes in the environment.
When the robot is deployed, it doesn’t know which of the staging aisles will be occupied or how full each isle will be.
The robot will therefore need to be taught between occupied and unoccupied aisles so it can change its path accordingly.
MIT is also investigating the potential for several of these robots to work together in teams.
‘As we drive the robot around the food bank, we are also researching new control policies that will allow the robot to adapt to changes in the environment and ensure all areas receive the proper estimated dosage,’ said Pierson.
‘We are focused on remote operation to minimise human supervision, and, therefore, the additional risk of spreading Covid-19, while running our system.’
Typically, the technique of ultraviolet germicidal irradiation is used in hospitals and medical settings to sterilise patient rooms when they’re not in use.
In this setting, it’s particularly directed at microorganisms such as methicillin-resistant staphylococcus aureus (MRSA), which can cause serious infections, like blood poisoning and toxic shock syndrome, and Clostridium difficile, a bacteria that can infect the bowel and cause diarrhoea.
The US military is also using UV light against the coronavirus, distributed by four-wheeled autonomous robots.
The bots are capable of radiating nearly 110 watts using a vertical UV mount that disinfects a surface two feet away in just over a minute.
China-based Keenon Robotics Company is also offering a $40,000 (£32,650) hospital robot that uses a combination of UV light and liquid disinfectant spray to kill the virus.
The fully-automated robot is armed with four groups of short-wave ultraviolet germ-killing lamps and five atomising disinfectant liquid spraying nozzles on its top.
Standing at 4.4 feet (1.4 metres) tall, the droid can carry 1500 millilitres of disinfectant liquid and takes six hours to fully charge.
While in South Korea, a company called UVLEN has created a ‘digital sanitiser’ clip-on device for smartphones that claims to turn a smartphone torchlight into UV.
A thin light diffraction filter on the device converts light from the smartphone torch into safe ‘far UVC’ – a form of UVC that efficiently inactivates bacteria without harm to exposed human skin.
‘Far-UVC light has a very limited range and cannot penetrate through the outer dead-cell layer of human skin or the tear layer in the eye, so it’s not a human health hazard,’ Professor David J. Brenner, Director of the Center for Radiological Research at Columbia University, previously explained.
Dr Brenner has previously given a TED talk on the potential of Far UVC and co-authored a 2018 research paper in Nature, describing it as a ‘new tool’ to control the spread of airborne-mediated microbial diseases over antibiotic drugs.
Handheld UV light devices that can kill Covid-19 may soon be as commonplace as mobile phones, researchers at Penn State University in the US claim.