Estimation of structure and motion parameters for a roaming robot that scans the space

We present a formulation for estimation of structure and motion parameters for a roaming robot that has translation on the floor and rotation along the vertical axis. To estimate the parameters, we use at least five feature correspondences among three viewpoints, where we ignore those vertical positioning. This is because the vertical changes in pointwise matching between two views is generally subtle in roaming robot environment, then it is practically hard for a traditional structure-from-motion estimation method (i.e., a pointwise matching method). Focusing on the horizontal changes, we use “directional feature” in panoramic images; we formulate the problem as the estimation of depth of the directional features and location of the viewpoints in the reference coordinate. Owing to the proposed method, more than 1000 panoramic images have been registered with calibrated location, and used for image-based rendering in computer graphics