Outdoor SLAM using Visual Appearance and Laser Ranging

— This paper describes a 3D SLAM system using information from an actuated laser scanner and camera installed on a mobile robot.The laser samples the local geometry of the environment and is used to incrementally build a 3D point-cloud map of the workspace. Sequences of images from the camera are used to detect loop closure events (without reference to the internal estimates of vehicle location) using a novel appearancebased retrieval system. The loop closure detection is robust to repetitive visual structure and provides a probabilistic measure of confidence. The images suggesting loop closure are then further processed with their corresponding local laser scans to yield putative Euclidean image-image transformations. We show how naive application of this transformation to effect the loop closure can lead to catastrophic linearization errors and go on to describe a way in which gross, pre-loop closing errors can be successfully annulled. We demonstrate our system working in a chall...

• Type: Conference
• Year: 2006
• Where: ICRA
• Authors: Paul M. Newman, David M. Cole, Kin Leong Ho
• Keywords: ICRA 2006, Loop Closure, Loop Closure Detection, Loop Closure Events, Robotics