Simultaneous people tracking and localization for social robots using external laser range finders

Robust localization of robots and reliable tracking of people are both critical requirements for the deployment of service robots in real-world environments. In crowded public spaces, occlusions can impede localization using on-board sensors. At the same time, teams of service robots working together need to share the locations of people and other robots on the same global coordinate system in order to provide services efficiently. To solve this problem, our approach is to use an infrastructure of sensors embedded in the environment to provide an inertial reference frame and wide-area coverage. Based on a people-tracking system we have previously established which uses laser range finders to track people´s trajectories, we have developed a technique to localize a team of service robots on a shared global coordinate system. Each robot´s odometry data is associated with the observed trajectory of an entity detected by the laser tracking system, and Kalman filters are used to correct rotational offsets between the robots´ individual coordinate systems and the global reference frame. We present our data association and pose correction algorithms and show results demonstrating the performance of our system in a shopping arcade.