A localization system based on buried magnets and dead reckoning for mobile robots

Localization problems are key concerns in the design of truly autonomous robots. If a robot does not know where it is, it will not be able to determine what to do next properly. In order to localize itself, a robot can use both relative and absolute measurement systems to get feedback about its driving actions and the environment perception. Usually, absolute localization is used periodically to correct drifts of relative localization performed with odometers, or inertial sensors. This absolute localization has to be as accurate as possible to give the robot the most reliable information on its position especially in docking situations. In this paper, we describe an absolute localization system able to determine the robot's position thanks to a magnet inserted into the ground. We have used a triangulation method to compute the position of the robot which provided us static and dynamic localization. This system has been embedded in an Auto Guided Vehicle (AVG) in an industrial context.