A Shared Autonomy Surface Disinfection System Using a Mobile Manipulator Robot

Robots are being increasingly used in the fight against highly-infectious diseases such as Ebola, MERS, and SARS-CoV-2. Many of these robots use ultraviolet lights mounted on a mobile base to inactivate the pathogens. While the lights are generally effective at irradiating open spaces and walls, they are less effective when it comes to horizontal surfaces, because of the orientation of the light sources. This can be problematic for pathogens such as Ebola, where transmission via contaminated work surfaces, which are often horizontal, is a concern. In this paper, we describe the design, implementation, and testing of an ultraviolet light disinfection system implemented on a mobile manipulator robot designed to address the problem of horizontal surface disinfection. A human supervisor designates a surface for disinfection, the robot autonomously plans and executes an end-effector trajectory to disinfect the surface to the required certainty, and then displays the results for the supervisor to verify. We also provide some background information on Ultraviolet Germicidal Irradiation (UVGI) and describe how we constructed and validated models of ultraviolet radiation propagation and accumulation in our system. Finally, we describe our implementation on a Fetch mobile manipulation platform, and discuss how the practicalities of implementation on a real robot affect our models.