Localization and map building using laser range sensors in outdoor applications

This paper presents the design of a high accuracy outdoor navigation system based on standard dead reckoning sensors and laser range and bearing infor mation. The data validation problem is addressed using laser intensity info rmation. The beacon design aspect and location of landmarks are also discus sed in relation to desired accuracy and required area of operation. The res ults are important for simultaneous localization and map building applicati ons (SLAM), since the feature extraction and validation are resolved at the sensor level using laser intensity. This facilitates the use of additional natural landmarks to improve the accuracy of the localization algorithm. T he modelling aspects to implement SLAM with beacons and natural features ar e also presented. These results are of fundamental importance because the i mplementation of the algorithm does not require the surveying of beacons. F urthermore we demonstrate that by using natural landmarks accurate localiza tion can be achieved by only requiring the initial estimate of the position of the vehicle. The algorithms are validated in outdoor environments using a standard utility car retrofitted with the navigation sensors and a 1 cm precision Kinematic GPS used as ground truth. (C) 2000 John Wiley & Sons, I nc.