Method and device arrangement for high-precision, (semi-) automatic in-situ calibration and registration of a projector-camera system to a component

摘要

Method for the highly accurate, (semi-) automatic in-situ calibration and registration of a projector-camera system to a component, comprising the following steps: - Projector and camera are positioned so that both devices point to the component and the component one preferably occupies the largest possible part of the image area of the projector and camera; The projector projects a sequence of structured light patterns onto the component; - The camera takes a picture of the so-lit component for each pattern; A rough estimate of the projector's main point and / or the camera's main point is taken, wherein the rough estimate of the projector's main point and / or the camera's main point is given at least once by a user or as a design-related value; Based on this, an initial projector-camera calibration (intrinsic: focal length, main point, extrinsic: rotation and translation) and a 3D reconstruction of the component is calculated by means of fundamental matrix decomposition; The 3D reconstruction is roughly aligned to a present virtual model of the component, in particular by predetermining or automatically determining rotation and / or translation and / or scaling of the 3D reconstruction; Iteratively calculated: a) a best fit of the 3D reconstruction to the virtual model of the component, b) an optimized projector camera calibration resulting from the best fit, preferably including a radial distortion parameter, and registration to the part, and c) a new 3D reconstruction based on the optimized calibration; - Calibration will stop when predefined Best Fit and / or Projector Camera Calibration thresholds are reached.