Path and Trajectory Planning for UV-C Disinfection Robots

Ultraviolet-C(UV-C) disinfection has been known for long, but its use with robotics is quite new, mainly motivated by the recent coronavirus disease pandemics (COVID-19). In UV-C disinfection, application of the right dose to target surfaces is fundamental to ensure proper disinfection. Hence a common goal is to provide a proper motion plan that ensures effective disinfection. In this letter, we provide a generic framework that generates a shortest path and the corresponding trajectory that ensures effective disinfection while optimizing different cost functions, and then experimentally verify it using a differential drive mobile robot. The trajectories generated by the proposed framework comply with kinodynamic constraints of the robot carrying the UV-C source. We also study non-uniform illumination and present a novel cost function that aims to decrease excessive illumination, in order to reduce UV-C damage of the surfaces. Additionally, we analyze the effect of height of line sources, which can change effectiveness and speed of disinfection considerably.