KELO Robotics GmbH

Project dates


Full title of the project:
Reducing infection rates in care facilities and crowded public areas by means of mobile robots carrying a battery of UV-C lamps

Short name of the project:
ARODIS (Autonomous robots for disinfection)

Date of the award:
27/06/2020

Project duration:
8 weeks

Company:
Kelo Robotics GmbH

Country:
Germany

Company Website:
http://www.kelo-robotics.com

Abstract

SARS-CoV-2 is one of the most infectious viruses that has struck human kind since the Spanish flu one hundred years ago. The rapid spread of the SARS-CoV-2 virus has been promoted by two aspects: a) People who carry the virus are infectious long before the first symptoms of COVID-19 appear, b) the aerosols emitted by an infected person through coughing or sneezing can remain in the air for hours and infect other people. This applies in particular to situations in which dense crowds are in closed rooms. As the outbreak in Heinsberg (Germany) has shown, one infectious person can infect hundreds of other people.

UV-C light has proven to be a very effective means for preventing the transfer of germs. UV-C light massively damages the DNA or RNA of germs and thus prevents their further spread. It has been shown that if a contaminated surface is illuminated with sufficient intensity and for a sufficient period of time, UV-C light can kill up to 99.99% and more of the germs on the surface. UV-C lamps are therefore already used in clinical environments for disinfection of sickrooms or sickbeds.

Unfortunately, UV-C light can cause considerable irritation to human skin and eyes over almost the entire range of its possible wavelengths (180 – 280 nm). Therefore, when UV-C light is used for the disinfection of a room, humans have to leave the room in order not to be harmed. Only a very small range of the total wavelengths of UV-C light was found to be safe for the human skin and eyes, namely UV with a wavelength of 222 nm (Welch et al. 2018). 222 nm UV light cannot penetrate the human epidermis and the cornea of the human eye. Unfortunately the availability of such UV-C lamps and LEDs is highly limited. UV light with a wavelength of 254 nm is relatively safe for the human skin because only 95% are absorbed by the outer dead layer of skin (Nardell et al. 2008) but may still harm the human eye.

We propose a fleet of autonomous mobile robots, which will carry a battery of 6 or more 254 nm UV lamps (due to the lack of 222nm UV lamps) and will move around a public environment and expose surfaces in the environment with 254 nm UV light with doses of 0.4 – 10 mJ/cm². At such doses the survival rate of germs is between 0.1 and 0.01%.

Our robots have two unique properties: a) they are inherently safe, omnidirectional and have a high maneuverability, which enables them to move in narrow space and in close proximity to humans; b) they are cost-efficient. Our solution will cost half the price of the systems on the market.

A true challenge for our solution and all disinfection robots with UV-C lamps is the health risk. The Directive 2006/25/EC put significant limit to the amount of UV-C light irradiated on the human body, which holds even for the promising 222nm solutions. We will address this problem by tracking humans in the proximity of the robot and adjusting the UV-C light doses accordingly.