Transprojection of geometry data

• US 7,693,325 B2
• Filed: 01/14/2004
• Issued: 04/06/2010
• Est. Priority Date: 01/14/2004
• Status: Active Grant

• Current Assignee: Hexagon Metrology Incorporated (Hexagon AB)
• Original Assignee: Hexagon Metrology Incorporated (Hexagon AB)
• Inventors: Eaton, Homer, Pulla, Sandeep
• Primary Examiner(s): Johns; Andrew W
• Assistant Examiner(s): Torres; Jose M
• Application Number:
  US10/758,696
• Publication Number:
  US 20050151963A1
• Time in Patent Office: 2,274 Days
• Field of Search: 382/107, 382/154, 335/03
• US Class Current: 382/154
• CPC Class Codes: G01B 21/02 for measuring length, width, or thickness G01B21/10 takes precedence
• CPC Class Codes: G01B 21/04 by measuring coordinates of points
• CPC Class Codes: G01B 9/02023 Indirect probing of object, e.g. via influence on cavity or fibre
• CPC Class Codes: G01B 9/02029 Combination with non-interferometric systems, i.e. for measuring the object
• CPC Class Codes: G01B 9/0203 With imaging systems
• CPC Class Codes: G01B 9/02031 With non-optical systems, e.g. tactile
• CPC Class Codes: G01B 9/0205 of probe head
• CPC Class Codes: G06T 11/60 Editing figures and text; Combining figures or text
• CPC Class Codes: G06T 2207/20221 Image fusion; Image merging
• CPC Class Codes: G06T 7/73 using feature-based methods

Abstract

A system and methods for transprojection of geometry data acquired by a coordinate measuring machine (CMM). The CMM acquires geometry data corresponding to 3D coordinate measurements collected by a measuring probe that are transformed into scaled 2D data that is transprojected upon various digital object image views captured by a camera. The transprojection process can utilize stored image and coordinate information or perform live transprojection viewing capabilities in both still image and video modes.

Claims

1. A system for coordinate visualization, the system comprising:

a measuring system for acquiring three dimensional coordinate data from a plurality of measurement locations on an object at least partially contained in a target area comprising at least one target delineator having a known positional relationship to the target area, the measuring system comprising an articulated arm portable coordinate measurement machine including a plurality of segments hingedly connected with a plurality of rotational transfer housings and a probe;

an imaging member that generates an image of at least a portion of the object and at least a portion of the target delineator from a vantage point whose three dimensional location is known; and

at least one module which receives the three dimensional coordinate data, the image and the three dimensional location, the at least one module overlaying a representation of the three dimensional coordinate data indicating the plurality of measurement locations on the object and the image of the object, the target delineator being used to calibrate the image of the target area,

wherein, calibration of the image of the target area further comprises;

acquiring three dimensional coordinate information for the target delineator and relating the three dimensional coordinate information for the target delineator to a target delineator representation in the image wherein the relationship is reflected by a calibration parameter, and

wherein, the calibration parameter is determined using a target detection functionality in which at least one module discerns a representation of the target delineator within the image and associates the target coordinate information with the representation of the target delineator.

2. The system for coordinate visualization of claim 1, wherein the imaging member is secured to the measuring system so as to be cooperatively positioned in conjunction with the measuring system to acquire the image from a selected perspective about the object.

3. The system of claim 1, wherein the probe is selected from the group consisting of:

a contact-sensitive probe, a remote-scanning probe, a laser-scanning probe, a probe that uses a strain gauge for contact detection, a probe that uses a pressure sensor for contact detection, a probe that uses an infrared beam for positioning, and a probe configured to be electrostatically-responsive.

4. The system for coordinate visualization of claim 1 wherein, the target detection functionality discerns the target delineator on the basis of at least one target delineator characteristic selected from the group consisting of:

shape, size, coloration, location, luminosity, brightness, and contrast.

5. The system for coordinate visualization of claim 4 wherein, the at least one target delineator characteristic is evaluated for at least one selected seed pixel of the image and a search is performed to identify other pixels associated with the target delineator.

6. The system for coordinate visualization of claim 5 wherein, the pixel identification search comprises a recursive search performed in the vicinity of the selected seed pixel.

7. The system for coordinate visualization of claim 1 wherein, the imaging member comprises a camera capable of generating still images or video images.

8. The system for coordinate visualization of claim 1 wherein, the imaging member comprises an imaging device selected from the group consisting of:

X-ray imaging devices, ultrasonic imaging devices, laser imaging devices, infrared imaging devices, optical imaging devices, and digital imaging devices.

9. The system for coordinate visualization of claim 1 wherein, the image is three dimensional in form.

10. The system according to claim 1, wherein at least one module produces image data overlaying a visible marker at a measurement locations on the image.

11. The system for coordinate visualization of claim 10, wherein the visible marker comprises coordinate information scaled and overlaid at the measurement locations on the image.

12. The system for coordinate visualization of claim 10, wherein at least one module overlays the visible marker on the image to reflect the position and orientation of the visible marker at the measurement locations in the context of the image perspective.

13. The system for coordinate visualization of claim 10, wherein at least one module overlays the visible marker at the measurement locations on the image by identifying a virtual coordinate system associated with the at least one image that is a scaled representation of a physical coordinate system associated with the measurement locations on the object such that the coordinate data obtained from the measurement locations on the object is modeled in the virtual coordinate system.

14. The system for coordinate visualization of claim 10, wherein a calibration parameter is applied to the coordinate data from the measurement locations on the object to accurately overlay the visible marker at the measurement locations on the image.

15. The system for coordinate visualization of claim 10, wherein the image is two dimensional in nature and the processor transforms the three dimensional coordinate data into a representative two dimensional form such that when the two dimensional form of the coordinate data is overlaid upon the image, the visible marker accurately reflects the position of the measurement locations in the context of the image.

16. The system for coordinate visualization of claim 15 wherein, the coordinate data transformation is accomplished using at least one imaging member modeling parameter.

17. The system for coordinate visualization of claim 10, wherein a plurality of images are acquired from various perspectives and the processor displays selected images with the overlaid visible marker on the basis of the measuring system location with respect to the object.

18. The system for coordinate visualization of claim 17 wherein, at least one module selects the image and visible marker to display by identifying the image closest in perspective to the vantage point of the measuring system position.

19. The system for coordinate visualization of claim 10, wherein at least one module displays the image and corresponding visible marker at the measurement locations on the image based upon at least one image characteristic.

20. The system for coordinate visualization of claim 19 wherein, the at least one image characteristic is selected from the group consisting of magnification, perspective, orientation, and view.

21. The system for coordinate visualization of claim 10, wherein at least one module performs an adjustment operation to the image and corresponding visible marker at the measurement locations on the image to achieve a selected view of the image.

22. The system for coordinate visualization of claim 21 wherein, the adjustment operation is selected from the group of operations consisting of realignment, rotation, skewing, cropping, and zooming.

23. The system for coordinate visualization of claim 10, wherein at least one module displays the image and visible marker in a live operational mode that is responsive to the position of measuring system as it is moved about the object.

24. A system for coordinate visualization, the system comprising:

a measuring system for acquiring three dimensional coordinate data from a plurality of measurement locations on an object at least partially contained in a target area comprising at least one target delineator having a known positional relationship to the target area, the measuring system comprising an articulated arm portable coordinate measurement machine including a plurality of segments hingedly connected with a plurality of rotational transfer housings and a probe;

an imaging member that generates an image of at least a portion of the object and at least a portion of the target delineator from a vantage point whose three dimensional location is known; and

at least one module which receives the three dimensional coordinate data, the image and the three dimensional location, the at least one module overlaying a representation of the three dimensional coordinate data indicating the plurality of measurement locations on the object and the image of the object, the target delineator being used to calibrate the image of the target area,

wherein at least one module produces image data overlaying a visible marker at a measurement locations on the image,

wherein a plurality of images are acquired from various perspectives and the processor displays selected images with the overlaid visible marker on the basis of the measuring system location with respect to the object,

wherein, at least one module selects the image and visible marker to display by identifying the image closest in perspective to the vantage point of the measuring system position, and

wherein, the position of the imaging member relative to the measuring system is interpolated or extrapolated from the associated coordinate data.

25. A system for coordinate visualization, the system comprising:

a measuring system for acquiring three dimensional coordinate data from a plurality of measurement locations on an object at least partially contained in a target area comprising at least one target delineator having a known positional relationship to the target area, the measuring system comprising an articulated arm portable coordinate measurement machine including a plurality of segments hingedly connected with a plurality of rotational transfer housings and a probe;

an imaging member that generates an image of at least a portion of the object and at least a portion of the target delineator from a vantage point whose three dimensional location is known; and

at least one module which receives the three dimensional coordinate data, the image and the three dimensional location, the at least one module overlaying a representation of the three dimensional coordinate data indicating the plurality of measurement locations on the object and the image of the object, the target delineator being used to calibrate the image of the target area,

wherein at least one module produces image data overlaying a visible marker at a measurement locations on the image, and

wherein at least one module selects an appropriate image and corresponding visible marker to display on the basis of a coordinate range associated with each image such that when the measuring system is positioned substantially within the coordinate range, the processor displays that image and corresponding visible marker at the measurement locations on the image.

26. A system for coordinate visualization, the system comprising:

a measuring system for acquiring three dimensional coordinate data from a plurality of measurement locations on an object at least partially contained in a target area comprising at least one target delineator having a known positional relationship to the target area, the measuring system comprising an articulated arm portable coordinate measurement machine including a plurality of segments hingedly connected with a plurality of rotational transfer housings and a probe;

an imaging member that generates an image of at least a portion of the object and at least a portion of the target delineator from a vantage point whose three dimensional location is known; and

at least one module which receives the three dimensional coordinate data, the image and the three dimensional location, the at least one module overlaying a representation of the three dimensional coordinate data indicating the plurality of measurement locations on the object and the image of the object, the target delineator being used to calibrate the image of the target area,

wherein at least one module comprises a target locator module to locate the at least one target delineator and provide an array of points associated with each target delineator within the images along with associated coordinate data, an image module in communication with the target locator module providing reference images to the target locator module, and a camera calibration module in communication with the target locator module, the camera calibration module receiving information relating to the object coordinate system and information relating to the at least one target delineator from the target locator module to generate a calibrated parameter set.

27. The system for coordinate visualization of claim 26, wherein at least one module translates the three dimensional location of the imaging member into three dimensional coordinates associated with a coordinate system for the object.

28. The system for coordinate visualization of claim 27, wherein at least one module utilizes at least one modeling parameter to relate the three dimensional location of the imaging member to the three dimensional coordinates associated with the coordinate system for the object.

29. The system for coordinate visualization of claim 28 wherein, the at least one modeling parameter is derived in part from focal characteristics of the imaging member.

30. The system for coordinate visualization of claim 29 wherein, the focal characteristics used to derive the at least one modeling parameter are selected from the group consisting of:

imaging member angle, imaging member focal length, imaging member distortion characteristics, imaging member offset characteristics, imaging member scaling characteristics, imaging member orientation, and imaging member position.

31. The system for coordinate visualization of claim 26 wherein, calibration of the image of the target area further comprises:

acquiring three dimensional coordinate information for the target delineator; and

relating the three dimensional coordinate information for the target delineator to a target delineator representation in the image wherein the relationship is reflected by a calibration parameter.

32. The system according to claim 26, wherein at least one module comprises a video renderer module including a video camera module in communication with the image module and a transprojection module, the transprojection module receiving calibrated parameters to accurately transproject the three-dimensional coordinate data onto each image provided by the video camera module.