Global Localization and Position Tracking of an Automated Guided Vehicle

Abstract

AbstractA swarm of Automated Guided Vehicles (AGVs) can be used in warehouses, distribution centers and manufacturing plants in order to automate the internal material flow. This swarm can overcome the disadvantages of roll conveyors and belts. The main problems of AGVs are global localization, position tracking, path planning and communication (especially within the swarm). Another technique which provides potential for logistic applications are Wireless Sensor Networks (WSNs). They can be used in warehouses to realize a decentralized stock database, monitoring a cold chain as well as for localization of an AGV and communication within the swarm. The paper presents a technique for global localization and position tracking of an omnidirectional AGV equipped with Mecanum wheels, which was designed to transport Euro-bins in a distribution center or warehouse. Global localization is realized through a technique based on range measurements obtained from an IEEE 802.15.4a WSN. The WSN is also used for communication within the swarm as well as for communication with the central warehouse computer. A developed sensor fusion of two safety laser range finders with the range measurements of a WSN solve the position tracking task. Laser range finders are used to detect pairs of landmarks to provide accurate positioning for docking maneuvers. The paper also presents a sensor model for IEEE 802.15.4a range measurements and experimental results. The latter show that the global localization technique guarantees accurate positioning and that the sensor fusion can be used for docking applications.