Particle Filter Based Sensor Fusion of Range Measurements from Wireless Sensor Network and Laser Range Finder

Automated Guided Vehicles (AGVs) are used in warehouses, distribution centers and manufacturing plants in order to automate the internal material flow. Usually AGVs are designed to transport large and heavy transport units such as Euro-pallets or mesh pallets. Just-in-time inventory management and lean production requires small transportation units. Furthermore short production cycles requires a flexible material flow which can not be fulfilled by continuous material handling devices like belt or roll conveyors. A solution to meet these demands are small mobile robots for material transport which can replace conventional conveyor systems or large AGVs. The paper presents localization and tracking of an omnidirectional mobile robot which is designed to transport Euro-bins in a distribution center or warehouse. Localization is realized by sensor fusion of range measurements obtained from an IEEE 802.15.4a network and a laser range finder. The laser range finder is used to detect landmarks and to provide accurate positioning for docking maneuvers. The range measurements are fused in a Monte Carlo Particlefilter. The paper presents the structure of the Particlefilter as well as experimental results.