Robust Person Guidance by using Online POMDPs Luis Merino 1 , Joaqu´ ın Ballesteros 2 , No´ e P´ erez-Higueras 1 , Rafael Ram´on Vigo 1 , Javier P´ erez-Lara 1 , and Fernando Caballero 2 1 Robotics, Vision and Control Group Universidad Pablo de Olavide, Sevilla, Spain, 2 Robotics, Vision and Control Group Universidad de Sevilla, Spain Abstract. The paper considers a guiding task in which a robot has to guide a person towards a destination. A robust operation requires to consider uncertain models on the person motion and intentions, as well as noise and occlusions in the sensors employed for the task. Partially Observable Markov Decision Processes (POMDPs) are used to model the task. The paper describes an enhancement on online POMDP solvers that allow to apply them to larger problems. The algorithm is used to control the robot in real-time for the guiding application. Results in simulation illustrate the approach. Keywords: robust navigation, POMDP 1 Introduction In the last years, there has been an impressive development on localization, mapping, SLAM and navigation techniques. The scale of the scenarios to which this techniques can be applied has increased dramatically. But despite all these advances, achieving long-term autonomy, either in space and time, requires to enhance the robustness of all these skills. For this, a robot should cope with imperfect information, failure modes, partial models, etc. In particular, we are interested in the robust operation of robots in human inhabited spaces. The FROG FP7 project 3 aims to deploy a guiding robot in touristic sites involving outdoor and partially outdoor scenarios. While robot guides has been developed since more than a decade [26, 19], the project considers as new contributions the development of social behaviors and their adaptation by integrating social feedback, as well as the robust operation in outdoors crowded scenarios. Furthermore, it aims to demonstrate the operation of the robot for two weeks at the Royal Alcazar in Seville (see Fig. 1). Among other activities, one particular application considered in the project is person guidance. Robustly navigating in these crowded scenarios (the Royal Alcazar may have around 5000 visits per day) requires to consider issues due 3 http://www.frogrobot.eu