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The aim of the present work is to contribute in the fight against the spread of Covid-19, a novel human coronavirus, in hospitals, public transport, airlines, and any enclosed areas. In this study, we have adopted the physical disinfection method by using UVC light as agent. The UVC devices are studied and classified according their disinfectant units, complementary devices, combined disinfection agents, mobilities, and order types. Our finding shows that a mobile robot is the most efficient device to inactivate microorganisms, so we have developed a robot called i-Robot UVC. The robot is equipped with eight UVC lamps around a central column and two lamps on the top. The column is fixed on a mobile base where several sensors are integrated to measure temperature and humidity on the one hand, and on the other, to detect motion plus position and to avoid obstacles. The robot can estimate automatically the disinfection time while monitored by Wi-Fi connection from a phone or a tablet. I-Robot UVC disinfects rooms and equipment with ultraviolet light, and shuts down when humans are around to keep them safe. The robot can kill 99,999% bacteria and various through UVC lamps led. The innovative robot UVC was patented under the number TN2020/0063.

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Currently, investigations are intensively conducted on modeling, forecasting, and studying the dynamic spread of coronavirus (Covid-19) new pandemic. In the present work, the sigmoidal-Boltzmann mathematical model was applied to study the Covid-19 spread in 15 different countries. The cumulative number of infected persons I has been accurately fitted by the sigmoidal-Boltzmann equation (SBE), giving rise to different epidemiological parameters such as the pandemic peak t p , the maximum number of infected persons I max , and the time of the epidemic stabilization t ∞. The time constant relative to the sigmoid Δt (called also the slope factor) was revealed to be the determining parameter which influences all the epidemiological parameters. Empirical laws between the different parameters allowed us to propose a modified sigmoidal-Boltzmann equation describing the spread of the pandemic. The expression of the spread speed V p was further determined as a function of the sigmoid parameters. This made it possible to assess the maximum speed of spread of the virus V pmax and to trace the speed profile in each country. In addition, for countries undergoing a second pandemic wave, the cumulative number of infected people I has been successfully adjusted by a double sigmoidal-Boltzmann equation (DSBE) allowing the comparison between the two waves. Finally, the comparison between the maximum virus spread of two waves V p max 1 and V p max 2 showed that the intensity of the second wave of Covid-19 is low compared to the first for all the countries studied.