Three-dimensional imager

• US 10,455,216 B2
• Filed: 08/10/2016
• Issued: 10/22/2019
• Est. Priority Date: 08/19/2015
• Status: Active Grant

• Current Assignee: Faro Technologies Incorporated
• Original Assignee: Faro Technologies Incorporated
• Inventors: Raab, Simon, Pfeffer, Charles, Tohme, Yazid, McArdle, Duncan Andrew, Bridges, Robert E., Choi, Jae-Woo
• Primary Examiner(s): Cattungal, Rowina J
• Application Number:
  US15/233,415
• Publication Number:
  US 20170054965A1
• Time in Patent Office: 1,168 Days
• CPC Class Codes: G01B 11/002 for measuring two or more coordinates
• CPC Class Codes: G01B 11/245 using a plurality of fixed, simultaneously operating transducers G01B11/2408 - G01B11/2425, G01B11/255 take precedence
• CPC Class Codes: G01B 11/25 by projecting a pattern, e.g. one or more lines, moiré fringes on the object G01B11/255 takes precedence ; image analysis for depth or shape recovery G06T7/50
• CPC Class Codes: G01B 11/2513 with several lines being projected in more than one direction, e.g. grids, patterns
• CPC Class Codes: G01B 21/042 Calibration or calibration artifacts G01B3/30, G01B9/02072 take precedence
• CPC Class Codes: G01C 11/02 Picture taking arrangements specially adapted for photogrammetry or photographic surveying, e.g. controlling overlapping of pictures
• CPC Class Codes: G06T 2207/30204 Marker
• CPC Class Codes: G06T 2207/30244 Camera pose
• CPC Class Codes: G06T 7/20 Analysis of motion motion estimation for coding, decoding, compressing or decompressing digital video signals H04N19/43, H04N19/51
• CPC Class Codes: G06T 7/60 Analysis of geometric attributes
• CPC Class Codes: G06T 7/70 Determining position or orientation of objects or cameras camera calibration G06T7/80
• CPC Class Codes: G06T 7/90 Determination of colour characteristics
• CPC Class Codes: H04N 13/239 using two 2D image sensors having a relative position equal to or related to the interocular distance H04N13/243 takes precedence
• CPC Class Codes: H04N 23/51 Housings
• CPC Class Codes: H04N 23/52 Elements optimising image sensor operation, e.g. for electromagnetic interference [EMI] protection or temperature control by heat transfer or cooling elements
• CPC Class Codes: H04N 23/55 Optical parts specially adapted for electronic image sensors; Mounting thereof
• CPC Class Codes: H04N 23/60 Control of cameras or camera modules
• CPC Class Codes: H04N 25/75 Circuitry for providing, modifying or processing image signals from the pixel array

Abstract

A three-dimensional (3D) measuring device includes a cooling fan and an enclosure attached to a projector and a camera. The camera images a pattern of light projected by the projector onto an object to determine 3D coordinates points on the object. A fan draws air through an opening in the front of the enclosure, across a plurality of components in the enclosure and out a second opening in the enclosure.

Claims

1. A three-dimensional (3D) measuring system comprising:

a first set of 3D imagers including two or more 3D imagers, each 3D imager of the first set of 3D imagers is designated by an index j between 1 and an integer N equal to or greater than 2, each 3D imager j configured to determine 3D coordinates of an object in an imager frame of reference, each 3D imager j having a 3D imager pose j within a system frame of reference, each 3D imager j including;

a projector j configured to project a patterned light over an area onto the object;

a camera j configured to capture an image of the patterned light on the object, the camera j including a lens j and a photosensitive array j, the camera j configured to image the patterned light on the object onto the photosensitive array j;

a processor j mechanically coupled to the projector j and the camera j, the processor j configured to determine the 3D coordinates of the object in the imager frame of reference based at least in part on the projected patterned light, the image of the patterned light on the object captured by the camera j, and a relative pose of the projector j with respect to the camera j;

a first mounting frame coupled to each 3D imager j in the first set of 3D imagers; and

a system controller configured to obtain a system collection of 3D coordinates, the system collection of 3D coordinates being 3D coordinates of the object in the system frame of reference, the system collection of coordinates based at least in part on the determined 3D coordinates of the object provided by the first set of 3D imagers and on the 3D imager pose j in the system frame of reference of each 3D imager j in the first set of 3D imagers, wherein the system controller is configured to receive position and orientation information of the first mounting frame from each processor j of the two or more 3D imagers, wherein the system controller is configured to register the system collection of 3D coordinates.

2. The 3D measuring system of claim 1 further comprising:

a second set of the 3D imagers, each designated by an index j between N +1 and an integer M, the integer M being equal to or greater than N +1, each 3D imager j of the second set of 3D imagers being coupled to a second mounting frame,

wherein the first set of 3D imagers and the second set of 3D imagers are arranged to measure different sides of the object,

wherein the first mounting frame is further attached to a mover device, the mover device being configured to change a pose of the first mounting frame, wherein the mover device is selected from the group consisting of;

a robot and a mobile platform,

wherein a portion of the system controller is coupled to the first mounting frame,

wherein the system controller includes an external computer not connected to the first mounting frame, wherein the system controller includes a collection of networked computers configured to perform parallel processing of the 3D coordinates provided by the first set of 3D imagers, and

wherein the object is coupled to a conveyor device, the conveyor device configured to move the object relative to the first set of 3D imagers.

3. The 3D measuring system of claim 1 further comprising:

a wide field-of-view (FOV) camera having a wider FOV than any camera j within the first set of 3D imagers, wherein the wide FOV camera is a color camera, the system controller being further configured to add color to a representation of the system collection of 3D coordinates,

wherein each 3D imager j in the first set of 3D imagers further includes a color camera j in addition to the camera j, and

wherein each processor j is further configured to integrate color into the determined 3D coordinates of the object.

4. The 3D measuring system of claim 1 further comprising a standoff structure coupled to the first mounting frame, the standoff structure configured to hold first targets configured to be imaged by the cameras j of the 3D imagers j, wherein the system controller is further configured to adjust the mover device to bring the standoff structure into proximity of the object so that at least one camera j captures an image that includes at least one first target and the object.

5. A three-dimensional (3D) measuring system comprising:

a first set of 3D imagers including two or more 3D imagers, each 3D imager of the first set of 3D imagers is designated by an index j between 1 and an integer N equal to or greater than 2, each 3D imager j configured to determine 3D coordinates of an object in an imager frame of reference, each 3D imager j having a 3D imager pose j within a system frame of reference, each 3D imager j including;

a projector j configured to project a patterned light over an area onto the object;

a camera j configured to capture an image of the patterned light on the object, the camera j including a lens j and a photosensitive array j, the camera j configured to image the patterned light on the object onto the photosensitive array j;

a processor j mechanically coupled to the projector j and the camera j, the processor j configured to determine the 3D coordinates of the object in the imager frame of reference based at least in part on the projected patterned light, the image of the patterned light on the object captured by the camera j, and a relative pose of the projector j with respect to the camera j;

a first mounting frame coupled to each 3D imager j in the first set of 3D imagers; and

a system controller configured to obtain a system collection of 3D coordinates, the system collection of 3D coordinates being 3D coordinates of the object in the system frame of reference, the system collection of coordinates based at least in part on the determined 3D coordinates of the object provided by the first set of 3D imagers and on the 3D imager pose j in the system frame of reference of each 3D imager j in the first set of 3D imagers;

wherein the first set of 3D imagers includes a first group of 3D imagers and a second group of 3D imagers, each 3D imager of the first group of 3D imagers associated with a corresponding first area of the object, each 3D imager of the second group of 3D imagers associated with a corresponding second area of the object, the 3D measuring system configured to;

in a first time interval, project patterned light by each 3D imager of the first group of 3D imagers onto the corresponding first area of the object, each of the corresponding first areas receiving no projected patterned light from any other 3D imager in the first set of 3D imagers, each 3D imager in the first group of 3D imagers further configured to determine 3D coordinates of the corresponding first area; and

in a second time interval, project patterned light by each 3D imager of the second group of 3D imagers onto the corresponding second area of the object, each of the corresponding second areas receiving no projected patterned light from any other 3D imager in the first set of 3D imagers, each 3D imager in the second group of 3D imagers further configured to determine 3D coordinates of the corresponding second area, and to read out electrical signals corresponding to at least a portion of images obtained by the first set of 3D imagers,

wherein during the first time interval, the system controller blanks each projector j in the second group of 3D imagers and determines at least a portion of the system collection of 3D coordinates collected based at least in part on 3D coordinates provided during a first time interval by the first set of 3D imagers

wherein during the second time interval, the system controller blanks each projector j in the first group of 3D imagers, and

wherein the first set of 3D imagers includes a third group of 3D imagers and a fourth group of 3D imagers, each 3D imager of the third group of 3D imagers associated with a corresponding third area of the object, each 3D imager of the fourth group of 3D imagers associated with a corresponding fourth area of the object, the 3D measuring system further configured to;

during the second time interval, read out electrical signals corresponding to at least a portion of images obtained by the first set of 3D imagers;

in a third time interval, project patterned light by each 3D imager of the third group of 3D imagers onto the corresponding third area of the object, each of the corresponding third areas receiving no projected patterned light from any other 3D imager in the first set of 3D imagers, each 3D imager in the third group of 3D imagers further configured to determine 3D coordinates of the corresponding third area, and read out electrical signals corresponding to at least a portion of images obtained by the second set of 3D imagers; and

in a fourth time interval, project patterned light by each 3D imager of the fourth group of 3D imagers onto the corresponding fourth area of the object, each of the corresponding fourth areas receiving no projected patterned light from any other 3D imager in the first set of 3D imagers, each 3D imager in the fourth group of 3D imagers further configured to determine 3D coordinates of the corresponding fourth area, and read out electrical signals corresponding to at least a portion of images obtained by the third set of 3D imagers,

wherein there is overlap among the areas covered by patterned light projected by the first group of 3D imagers, the second group of 3D imagers, the third group of 3D imagers, and the fourth group of 3D imagers.

6. A three-dimensional (3D) measuring system comprising:

a first set of 3D imagers including two or more 3D imagers, each 3D imager of the first set of 3D imagers is designated by an index j between 1 and an integer N equal to or greater than 2, each 3D imager j configured to determine 3D coordinates of an object in an imager frame of reference, each 3D imager j having a 3D imager pose j within a system frame of reference, each 3D imager j including;

a projector j configured to project a patterned light over an area onto the object;

a camera j configured to capture an image of the patterned light on the object, the camera j including a lens j and a photosensitive array j, the camera j configured to image the patterned light on the object onto the photosensitive array j;

a processor j mechanically coupled to the projector j and the camera j, the processor j configured to determine the 3D coordinates of the object in the imager frame of reference based at least in part on the projected patterned light, the image of the patterned light on the object captured by the camera j, and a relative pose of the projector j with respect to the camera j;

a first mounting frame coupled to each 3D imager j in the first set of 3D imagers; and

a system controller configured to obtain a system collection of 3D coordinates, the system collection of 3D coordinates being 3D coordinates of the object in the system frame of reference, the system collection of coordinates based at least in part on the determined 3D coordinates of the object provided by the first set of 3D imagers and on the 3D imager pose j in the system frame of reference of each 3D imager j in the first set of 3D imagers;

a collection of fiducial targets coupled to the first mounting frame, wherein the collection of fiducial targets are retroreflectors, light sources, or spherically mounted retroreflectors configured to attach to magnetic nests coupled to the first mounting frame.

a scale bar, the scale bar including a first fiducial target and a second fiducial target within the collection of fiducial targets, a distance between the first fiducial target and the second fiducial target being a reference distance,

wherein each 3D imager j from the first set of 3D imagers is configured to measure a collection of fiducial targets, the position of each fiducial target having 3D coordinates in a first frame of reference, and

wherein the system controller is configured to determine the 3D imager pose j for each 3D imager j of the first set of 3D imagers based at least in part on the 3D coordinates of the fiducial targets in the first frame of reference and the 3D coordinates of the fiducial targets as determined by each 3D imager j within the first set of 3D imagers

wherein the system controller is further configured to determine the 3D imager pose j for each 3D imager j of the first set of 3D imagers further based on the reference distance and on 3D coordinates of the first fiducial target and the second fiducial target as determined by the 3D measuring system.

7. A three-dimensional (3D) measuring system comprising:

a first set of 3D imagers including two or more 3D imagers, each 3D imager of the first set of 3D imagers is designated by an index j between 1 and an integer N equal to or greater than 2, each 3D imager j configured to determine 3D coordinates of an object in an imager frame of reference, each 3D imager j having a 3D imager pose j within a system frame of reference, each 3D imager j including;

a projector j configured to project a patterned light over an area onto the object;

a camera j configured to capture an image of the patterned light on the object, the camera j including a lens j and a photosensitive array j, the camera j configured to image the patterned light on the object onto the photosensitive array j;

a processor j mechanically coupled to the projector j and the camera j, the processor j configured to determine the 3D coordinates of the object in the imager frame of reference based at least in part on the projected patterned light, the image of the patterned light on the object captured by the camera j, and a relative pose of the projector j with respect to the camera j;

a first mounting frame coupled to each 3D imager j in the first set of 3D imagers; and

a system controller configured to obtain a system collection of 3D coordinates, the system collection of 3D coordinates being 3D coordinates of the object in the system frame of reference, the system collection of coordinates based at least in part on the determined 3D coordinates of the object provided by the first set of 3D imagers and on the 3D imager pose j in the system frame of reference of each 3D imager j in the first set of 3D imagers;

a mover device configured to change a relative position of the object and the first set of 3D imagers;

a collection of fiducial targets placed between the object and the 3D imagers; and

a collection of fiducial targets configured to be held stationary relative to one of the object or the first set of 3D imagers, the object being configured to change its pose relative to the first set of 3D imagers,

wherein the system controller further includes a user interface configured to enable selection of 3D imagers j to be included in the first set of 3D imagers, the user interface permitting a user to select a plurality of imagers to include in the first set of 3D imagers, wherein the user interface permits users to select 3D imagers j to include in the first set of 3D imagers based on a serial number, an internet protocol (IP) address, or both.