Dense, Auto-Calibrating Visual Odometry from a Downward-Looking Camera

Abstract

We present a technique whereby a single camera can be used as a high precision visual odometry sensor in a range of practical settings using simple, computationally efficient techniques. Taking advantage of the local planarity of common floor surfaces, we use real-time dense alignment of a 30Hz video stream as the camera looks down from a fast-moving robot, making use of the whole texture available rather than sparse feature points. Our key novelty, and crucial to the practicality of this approach, is rapid and automatic calibration for 6DoF camera extrinsics relative to the robot frame. Our experiments show robust performance over a range of low-textured real surfaces.