Dynamic calibration of a structured light system via planar motion

Abstract

Active vision is widely used in robotics. However, it should be calibrated carefully before a vision task. In this paper, we propose a closed-form solution for dynamic calibration and 3D reconstruction using structured light system. In this system, we assume that the light planes cast from the DLP projector are calibrated and kept constant while the principal point of the camera is known. When the camera undergoes a planar motion, its effective focal lengths (measured in width and height of the pixels respectively) and motion parameters can be calibrated dynamically. Then the 3D reconstruction can be effectively carried out with only a single image of the concerned scene. This feature is significant for many dynamic environments. In some practical applications, such as robot navigation along ground plane, planar motion is sufficient and our method provides an effective solution.