Among the robots responding to the novel coronavirus crisis are disinfection systems using ultraviolet light to kill pathogens. However, UV radiation can also be harmful to humans, so such robots need to operate autonomously, or they cannot work in spaces such as hospital rooms if people are present. Akara Robotics Ltd. has released Violet, a disinfection robot that can sense people and turn off its emitter if necessary.
“We’ve been exploring a disinfectant application for the last year or so, and we came together and decided to develop a dedicated UV robot” he told The Robot Report. Violet is the latest robot addressing the COVID-19 pandemic.
Movidius optimizes vision processing
“With Violet, we focused on learning models, robotic navigation, and computer vision,” said Niamh Donnelly, co-founder and director of AI at Akara.
How is Violet’s vision different from that of other mobile robots? “There are two parts. The first is that computer vision is normally on a power-hungry CPU or GPU,” explained Jonathan Byrne, data scientist, senior software developer, and chief drone pilot at Intel Corp.‘s Movidius unit. “Movidius is low power, which lends itself to robotics, which needs a powerful processor. The whole stack might be easier to program, but it’s difficult to keep at low power.”
“Movidius includes optimized cores and a pipeline that can pull a frame into RAM processing with 10 reads from memory on a dedicated CPU,” he said. “Movidius processes line by line, in parallel, and hits with many filters at once.”
“Since Myriad X, we now have an embedded chip system dedicated to deep learning, before the perceptual stack. We can optimize multiple networks to run simultaneously on the hardware,” Byrne said. “This is useful for tracking, identifying people, or detecting whether they’re happy or sad.”
Designing Violet for collaborative cleaning
“There are a number of factors to consider for a UV disinfection robot, from a design perspective,” said McGinn. “The first is the total power of light, where intensity follows an inverse square law. You either need powerful lighting rigs to cover a room or intelligent navigation with a lower-powered light.
“Violet can move more and get closer to surfaces — most go to two or three places within a room; we go to four or five,” he said. “The effectiveness was verified by an independent microbiology lab.”
“The second point is safety — it’s important to categorize whether someone is patient or visitor, who is not likely to be the first person to share a room with a robot,” McGinn said. “More likely, it would be the cleaning or medical team, which is more familiar with standard operating procedures and wearing personal protective equipment with specifications for occupational exposure limits.”
A robot operator could remotely control Violet, or a cleaner could even work alongside a robot, McGinn said. “We’ve been working in hospitals with staffers on procedural elements, such as what combination of UV and friction [human scrubbing] is needed,” he said. “Only then do we bring in artificial intelligence, which provided the opportunity to use computer vision and person tracking to turn lights on and off.”
“Not only can the robot direct where the light shines — every item has to withstand UV, which CT scans cannot — but we can also actually control what areas of the room are disinfected with UV-C,” said Donnelly. “Violet has a 360-degree field of view, so it can detect exactly where a person is in a room and shield them from radiation.
“By maneuvering more, we were able to go into the radiology department, which had previously considered robots but decided against them because they couldn’t get behind the CT scanner, which left a huge shadow. Our design decisions were defined by the users,” she said.