Abstract: A method and a system are disclosed for maintaining accuracy of a photogrammetry system comprising a stereo pair of cameras and characterized by calibration parameters determined at initialization, the system for tracking one of a touch probe and a 3D sensor, the method comprising in use, continuously detecting a presence of a reduced number of 3D target points comprising at least one pair of 3D target points selected in a group comprising at least two 3D target points; measuring image position data associated with the at least one pair of 3D target points of the reduced number of 3D target points; computing at least one updated calibration parameter using the measured image position data and corresponding reference distance data associated with the at least one pair of 3D target points of the reduced number of 3D target points; and updating at least one calibration parameter of the photogrammetry system.

Abstract: A method for matching points between three images of a scene comprises retrieving three images acquired by a sensor, extracting blobs from said reflection in said two images; for each given extracted blob of the first image: selecting a selected epipolar plane; identifying plausible combinations; calculating a matching error; repeating the steps of selecting, identifying and calculating for each epipolar plane of the set of epipolar planes; determining a most probable combination; identifying matching points between the two images; validating the matching points between the two images, said validating comprising for each pair of matching points, determining a projection of the pair of matching points in a third image of the third camera; and providing the validated pairs of matching points.

Abstract: A system and a method for providing an indication about positioning unreliability are described. The system comprises a scanner for scanning a surface geometry of an object and accumulating 3D points for each frame using shape-based positioning; a pose estimator for estimating an estimated pose for the scanner using the 3D points; an unreliable pose detector for determining if the estimated pose has an underconstrained positioning and an indication generator for generating an indication that the unreliable pose estimation is detected. In one embodiment, a degree of freedom identifier identifies a problematic degree of freedom in the estimated pose. In one embodiment, a feature point detector detects a reobservable feature point and the pose estimator uses the feature point with the 3D points to estimate the estimated pose and the unreliable pose detector uses the feature point to identify the estimated pose as an unreliable pose estimation.

Abstract: A system and a method for providing an indication about positioning unreliability are described. The system comprises a scanner for scanning a surface geometry of an object and accumulating 3D points for each frame using shape-based positioning; a pose estimator for estimating an estimated pose for the scanner using the 3D points; an unreliable pose detector for determining if the estimated pose has an under constrained positioning and an indication generator for generating an indication that the unreliable pose estimation is detected. In one embodiment, a degree of freedom identifier identifies a problematic degree of freedom in the estimated pose. In one embodiment, a feature point detector detects a reobservable feature point and the pose estimator uses the feature point with the 3D points to estimate the estimated pose and the unreliable pose detector uses the feature point to identify the estimated pose as an unreliable pose estimation.

Abstract: A method for matching points between three images of a scene comprises retrieving three images acquired by a sensor, extracting blobs from said reflection in said two images; for each given extracted blob of the first image: selecting a selected epipolar plane; identifying plausible combinations; calculating a matching error; repeating the steps of selecting, identifying and calculating for each epipolar plane of the set of epipolar planes; determining a most probable combination; identifying matching points between the two images; validating the matching points between the two images, said validating comprising for each pair of matching points, determining a projection of the pair of matching points in a third image of the third camera, determining if the projection of the pair of matching points in the third image of the third camera is located on a blob, identifying the pair of matching points as validated if the projection of the pair of matching points in the third image of the third camera is located on

Abstract: A method for matching points between two images of a scene acquired by two cameras, the method including: extracting blobs from the reflection in the images and individually labelling the blobs with a unique identifier; selecting a selected epipolar plane and defining a conjugate epipolar line on each of the images; identifying plausible combinations including a light sheet label of the projected pattern and the unique identifier for a plausible blob selected from the blobs in each of the images; calculating a matching error for each of the plausible combinations; repeating the steps of selecting, identifying and calculating for at least some epipolar planes; determining a most probable combination by computing a figure of merit for the plausible combinations; identifying matching points in the frame from the most probable combination.

Abstract: A system for obtaining three-dimensional information about a surface, the system comprising: a sensing device having: a pattern projector for providing a projected pattern on the surface; and a camera for acquiring a 2D image of the surface from a viewpoint, wherein at least one target of a set of reference targets and at least a portion of the projected pattern is apparent on the 2D image; a storage for calibration data; an image processor for extracting 2D image coordinates of surface points of the projected pattern and target contours from the 2D image; a 3D surface point calculator for calculating 3D coordinates of the surface points from the 2D image coordinates of the surface points; a 3D target calculator for calculating a 3D position and/or an actual orientation for the reference target.

Abstract: A method for matching points between two images of a scene acquired by two cameras, the method including: extracting blobs from the reflection in the images and individually labelling the blobs with a unique identifier; selecting a selected epipolar plane and defining a conjugate epipolar line on each of the images; identifying plausible combinations including a light sheet label of the projected pattern and the unique identifier for a plausible blob selected from the blobs in each of the images; calculating a matching error for each of the plausible combinations; repeating the steps of selecting, identifying and calculating for at least some epipolar planes; determining a most probable combination by computing a figure of merit for the plausible combinations; identifying matching points in the frame from the most probable combination.

Abstract: A method for obtaining a refined pose for a 3D sensor for online 3D modeling of a surface geometry of an object, the pose encompassing six degrees of freedom (DOF) including three translation parameters and three orientation parameters, the method comprising: providing the 3D sensor, the 3D sensor being adapted to capture 3D point measurements of the surface of the object from a viewpoint; providing a geometry model of at least part of the surface; observing a portion of the surface of the object with the 3D sensor; measuring an initialization pose for the 3D sensor by at least one of positioning device pose measurement, predicted pose tracking and target observation; finding a best fit arrangement of the 3D point measurements in the geometry model using the initialization pose; generating the refined pose for the 3D sensor using the best fit arrangement.

Abstract: A system and a method for providing an indication about positioning unreliability are described. The system comprises a scanner for scanning a surface geometry of an object and accumulating 3D points for each frame using shape-based positioning; a pose estimator for estimating an estimated pose for the scanner using the 3D points; an unreliable pose detector for determining if the estimated pose has an under constrained positioning and an indication generator for generating an indication that the unreliable pose estimation is detected. In one embodiment, a degree of freedom identifier identifies a problematic degree of freedom in the estimated pose. In one embodiment, a feature point detector detects a reobservable feature point and the pose estimator uses the feature point with the 3D points to estimate the estimated pose and the unreliable pose detector uses the feature point to identify the estimated pose as an unreliable pose estimation.

Abstract: A method for preparing a spatial coded slide image in which a pattern of the spatial coded slide image is aligned along epipolar lines at an output of a projector in a system for 3D measurement, comprising: obtaining distortion vectors for projector coordinates, each vector representing a distortion from predicted coordinates caused by the projector; retrieving an ideal pattern image which is an ideal image of the spatial coded pattern aligned on ideal epipolar lines; creating a real slide image by, for each real pixel coordinates of the real slide image, retrieving a current distortion vector; removing distortion from the real pixel coordinates using the current distortion vector to obtain ideal pixel coordinates in the ideal pattern image; extracting a pixel value at the ideal pixel coordinates in the ideal pattern image; copying the pixel value at the real pixel coordinates in the real slide image.

Abstract: A method for preparing a spatial coded slide image in which a pattern of the spatial coded slide image is aligned along epipolar lines at an output of a projector in a system for 3D measurement, comprising: obtaining distortion vectors for projector coordinates, each vector representing a distortion from predicted coordinates caused by the projector; retrieving an ideal pattern image which is an ideal image of the spatial coded pattern aligned on ideal epipolar lines; creating a real slide image by, for each real pixel coordinates of the real slide image, retrieving a current distortion vector; removing distortion from the real pixel coordinates using the current distortion vector to obtain ideal pixel coordinates in the ideal pattern image; extracting a pixel value at the ideal pixel coordinates in the ideal pattern image; copying the pixel value at the real pixel coordinates in the real slide image.

Abstract: There are provided systems and methods for obtaining a three-dimensional surface geometric characteristic and/or texture characteristic of an object. A pattern is projected on a surface of said object. A basic 2D image of said object is acquired; a characteristic 2D image of said object is acquired; 2D surface points are extracted from said basic 2D image, from a reflection of said projected pattern on said object; a set of 3D surface points is calculated in a sensor coordinate system using said 2D surface points; and a set of 2D surface geometric/texture characteristics is extracted.

Abstract: An auto-referenced sensing device for scanning an object to provide three-dimensional surface points, including: a Light-Emitting Diode (LED) light source emitting light for illuminating and enabling image acquisition of retro-reflective target positioning features provided at a fixed position on the object; a laser pattern projector, additional to the LED light source, for providing a projected laser pattern on a surface of the object for illuminating and enabling image acquisition of dense points between the retro-reflective target positioning features; at least a pair of cameras for simultaneously acquiring a 2D image of the object, the projected laser pattern and the retro-reflective target positioning features are apparent on the image, wherein the simultaneous images contain both positioning measurements from the retro-reflective target positioning features and dense surface measurements from the points enabled by the projected laser pattern.

Abstract: A method and hand-held scanning apparatus for three-dimensional scanning of an object is described. The hand-held self-referenced scanning apparatus has a light source for illuminating retro-reflective markers, the retro-reflective markers being provided at fixed positions on or around the object, a photogrammetric high-resolution camera, a pattern projector for providing a projected pattern on a surface of the object; at least a pair of basic cameras, the basic camera cooperating with light sources, the projected pattern and at least a portion of the retro-reflective markers being apparent on the 2D images, a frame for holding all components in position within the hand-held apparatus, the frame having a handle, the frame allowing support and free movement of the scanning apparatus by a user.

Abstract: A method for obtaining three-dimensional surface points of an object in an object coordinate system having two groups of steps. The method includes providing a set of target positioning features on the object. In a first group of steps, acquiring 2D first images of the object, extracting 2D positioning features; calculating a first set of calculated 3D positioning features; computing first transformation parameters, cumulating the first set of transformed 3D positioning features to provide and augment the set of reference 3D positioning features. In a second group of steps, providing a projected pattern on a surface of the object; acquiring 2D second images of the object, extracting 2D surface points and second sets of 2D positioning features; calculating a set of 3D surface points; calculating a second set of calculated 3D positioning features; computing second transformation parameters, transforming the 3D surface points into transformed 3D surface points.

Abstract: A system, apparatus and method for three-dimensional scanning and digitization of the surface geometry of objects are claimed. The system includes a hand-held apparatus that is auto-referenced. The system is auto-referenced since it does not need any positioning device to provide the 6 degree of freedom transformations that are necessary to integrate 3D measurements in a global coordinate system while the apparatus is manipulated to scan the surface. The system continuously calculates its own position and orientation from observation while scanning the surface geometry of an object. To do so, the system exploits a triangulation principle and integrates an apparatus that captures both surface points originating from the reflection of a projected laser pattern on an object's surface and 2D positioning features originating from the observation of target positioning features.

Abstract: An apparatus for producing a personalized 3D object is disclosed. The apparatus, or kiosk, comprises a payment detector, a user input device and a display, an image acquisition system, calculators for calculating a 3D image, a manufacturing device and an exit for delivering the personalized 3D object to the user. The manufacturing device includes a loading device for loading blank 3D objects on a platform, which includes vertical storages and a rotatable tray disposed underneath having a slit therein for receiving the blank 3D objects. The rotatable tray is computer controlled to rotated between various operative positions for loading and unloading the 3D objects.

Abstract: A system, apparatus and method for three-dimensional scanning and digitization of the surface geometry of objects are claimed. The system comprises a hand-held apparatus that is auto-referenced. The system is auto-referenced since it does not need any positioning device to provide the 6 degree of freedom transformations that are necessary to integrate 3D measurements in a global coordinate system while the apparatus is manipulated to scan the surface. The system continuously calculates its own position and orientation from the reflection of a projected laser pattern on an object's surface and 2D positioning features originating from the observation of target positioning features. Using the described system, it is possible to simultaneously build and match a 3D representation of the positioning features while accumulating the 3D surface points describing the surface geometry.