Euclidean reconstruction and affine camera calibration using controlled robot motions

Using Controlled Robot Motions Radu Horaud, St ephane Christy, and Roger Mohr GRAVIR{IMAG & INRIA Rhône-Alpes 655, avenue de l'Europe 38330 Montbonnot Saint-Martin FRANCE Abstract In this paper we are addressing the problem of Euclidean reconstruction with an uncalibrated a ne camera and calibration of this camera. Since e ciency is an important issue in robotics and computer vision, we investigate constraints under which the Euclidean shape and motion problem becomes linear. The theoretical study that is described in this paper leads us to impose some practical constraints, namely we require that the camera is mounted onto a robot arm and that the robot is executing controlled motions whose parameters are known. The a ne camera model considered here is certainly just an approximation of the true projective mapping. Nevertheless, there is a large number of applications for which the camera is allowed to be at some distance from the scene and under these circumstances the a ne model is a good approximation. The fact that we deal with an uncalibrated camera is an advantage over previous methods because we do not rely anymore on the tedious task of camera calibration. The experiments that are described at the end of the paper show that the method described herein compares favorably with other similar methods.