US 11,893,744 B2
Methods and apparatus for extracting profiles from three-dimensional images
Hongwei Zhu, Natick, MA (US); Nathaniel Bogan, Natick, MA (US); and David J. Michael, Waban, MA (US)
Assigned to Cognex Corporation
Filed by Cognex Corporation, Natick, MA (US)
Filed on May 10, 2021, as Appl. No. 17/316,417.
Claims priority of provisional application 63/023,179, filed on May 11, 2020.
Prior Publication US 2021/0350615 A1, Nov. 11, 2021
Int. Cl. G06T 17/00 (2006.01); G06T 7/12 (2017.01); G06F 18/2134 (2023.01)
CPC G06T 7/12 (2017.01) [G06F 18/21345 (2023.01); G06T 17/00 (2013.01)] 23 Claims
OG exemplary drawing
 
1. A computerized method for determining two-dimensional (2D) profiles of a portion of a three-dimensional (3D) point cloud of an object, the method comprising:
receiving data indicative of the 3D point cloud of the object comprising a plurality of 3D points;
determining a 3D region of interest in the 3D point cloud;
determining a plurality of different 3D subregions in the 3D region of interest, wherein each of the plurality of 3D subregions comprises a width along a corresponding first axis, a height along a corresponding second axis, and a depth along a corresponding third axis;
determining a plurality of sets of 3D points of the plurality of 3D points corresponding to the plurality of 3D subregions, wherein for each set of the plurality of sets of 3D points, each 3D point comprises a 3D location within the 3D subregion corresponding to the set of 3D points; and
for each set of the plurality of sets of 3D points:
representing the set of 3D points from three dimensions to only two dimensions as a set of 2D points based on coordinate values of the corresponding first and second axes of the set of 3D points;
grouping the set of 2D points into a plurality of 2D bins arranged along the corresponding first axis based on coordinate values of the corresponding first axis, wherein each 2D bin comprises a bin width;
determining, for each of the plurality of 2D bins, a representative 2D position based on the coordinate values of the corresponding second axis of the associated set of 2D points, wherein each representative 2D position includes associated coordinate values of the corresponding first and second axes; and
connecting each of the representative 2D positions to neighboring representative 2D positions to generate a 2D profile of the object along the corresponding first and second axes.