Homography Estimation of a Moving Planar Scene from Direct Point Correspondence

Abstract

Homographies provide a robust and reliable cue for visual servo control of robots. Some nonlinear observers have been recently developed for the estimation of temporal sequences of homographies associated with rigid-body motion of a camera observing a stationary planar scene. However, these algorithms do not model well time-varying changes in the homography velocity and tend to perform poorly when the camera or the scene moves fast. In this paper, an internal model-based observer posed on SL(3) for homography estimation is proposed allowing for dealing with complex camera-scene trajectories such as circular and sinusoidal motions of the camera and/or the scene. Rigorous proof of local asymptotic stability is established and excellent performance of the proposed observer is justified by experiments using an IMU-Camera prototype observing an oscillating planar target.