COORDINATE MEASURING MACHINE HAVING A CAMERA

• US 20150049186A1
• Filed: 12/06/2012
• Published: 02/19/2015
• Est. Priority Date: 12/06/2011
• Status: Active Grant

• Current Assignee: Hexagon Technology Center GmbH (Hexagon AB)
• Original Assignee: Hexagon Technology Center GmbH (Hexagon AB)
• Inventors: Pettersson, Bo, Siercks, Knut, Voit, Eugen, Hinderling, Jrg, Zebhauser, Benedikt, Schneider, Klaus, Jordil, Pascal
• Granted Patent: US 10,401,144 B2
• Time in Patent Office: Days
• US Class Current: 348/135
• CPC Class Codes: G01B 11/005 coordinate measuring machines
• CPC Class Codes: G01B 21/047 Accessories, e.g. for positioning, for tool-setting, for measuring probes
• CPC Class Codes: G05B 19/401 characterised by control arrangements for measuring, e.g. calibration and initialisation, measuring workpiece for machining purposes G05B19/19 takes precedence
• CPC Class Codes: G05B 2219/37193 Multicoordinate measuring system, machine, cmm
• CPC Class Codes: G05B 2219/37237 Tool collision, interference
• CPC Class Codes: G06F 3/005 Input arrangements through a video camera
• CPC Class Codes: G06F 3/0304 Detection arrangements using opto-electronic means constructional details of pointing devices not related to the detection arrangement using opto-electronic means G06F3/033; optical digitisers G06F3/042
• CPC Class Codes: Y02P 90/02 Total factory control, e.g. smart factories, flexible manufacturing systems [FMS] or integrated manufacturing systems [IMS]

Abstract

A coordinate measuring machine (1) for determining at least one spatial coordinate of a measurement point of an object (15) to be measured, comprising a base (5) and a drive mechanism, adapted to drive a probe head (13) in a manner such that the probe head (13) is capable to move relative to the base (5) for approaching a measurement point, characterised by a first range camera (3, 33) having a range image sensor with a sensor array, wherein the range camera (3, 33) is adapted to be directed to the object (15) for providing a range image (23) of the object (15), and wherein range pixels of the range image are used for creating a point cloud with 3D-positions of target points of the object (15), and a controller, adapted to control the drive mechanism on the basis of 3D-positions of the target points.

Claims

1-24. -24. (canceled)

25. A coordinate measuring machine for determining at least one spatial coordinate of a measurement point of an object to be measured, comprising:

a base,

a drive mechanism, adapted to drive a probe head in a manner such that the probe head is capable to move relative to the base for approaching a measurement point,

a frame structure, to which the probe head is attached, the frame structure being movable in a horizontal and a vertical direction,

a first camera, wherein the first camera is adapted to be directed to a measuring volume for providing at least a first image of at least a first part of the measuring volume, the measuring volume representing a particular volume inside which the at least one spatial coordinate of the measurement point is determinable as to a design of the coordinate measuring machine, as to a provided mobility of the probe head, and

a controller, adapted to control the drive mechanism on the basis of image data derived from the at least first image.

26. The coordinate measuring machine according to claim 25, wherein

the first camera is built as a first range camera having a range image sensor with a sensor array, wherein the range camera is adapted to be directed to the object for providing the at least first image as a range image of the object, and wherein range pixels of the range image are used as the image data for creating a point cloud with 3D-positions of target points of the object, and

the controller is adapted to control the drive mechanism on the basis of 3D-positions of the target points.

27. The coordinate measuring machine according to claim 26, comprising

a second range camera, which is adapted to be directed to the object from a direction different to that of the first range camera for providing a second range image of an area of the object being not visible for the first range camera, and wherein the controller is adapted to use 3D-data from either of the range images, depending on the position and moving direction of the probe head.

28. The coordinate measuring machine according to claim 26, wherein the first range camera or an additional range camera provides a range image stream, and the controller is adapted to control the drive mechanism on the basis of the range image stream.

29. The coordinate measuring machine according to claim 26, furthermore comprising reference objects positioned on the base in such a way that they can be viewed by the at least one range camera, for being made visible on a range image, and be approached by the probe head.

30. The coordinate measuring machine according to claim 25, wherein the controller is adapted for execution of:

a measuring mode for precisely determining the at least one spatial coordinate of the object to be measured, on execution of which

the probe head is guided relatively to the object on a predefined measurement path and

the at least one spatial coordinate of the measurement point of the object is derived from a measurement to the measurement point and

an object-determination functionality, on execution of which

surface data related to a surface of a body inside the measuring volume is derived from at least the first image by image processing as the image data and

controlling information is derived depending on the surface data for controlling the guidance of the probe head,

wherein the object-determination functionality is executed in advance of the measuring mode and the controlling information is provided for execution of the measuring mode.

31. The coordinate measuring machine according to claim 30, wherein on execution of the object-determination functionality:

an actual position and/or an actual orientation of the object located in the measuring volume is determined on basis of the surface data,

the actual position and/or actual orientation is compared with a given demanded position and/or a given demanded orientation for the object in the measuring volume and

the controlling information is generated depending on the comparison.

32. The coordinate measuring machine according to claim 30, wherein the object-determination functionality comprises a step of error detection, wherein the derived surface data is analyzed on basis of known measuring volume properties and a presence of the object to be measured or of an obstacle is checked and output information is generated depending on the check, wherein the controlling information is generated depending on the presence.

33. The coordinate measuring machine according to claim 25, wherein a set of defined object data provides:

surface profiles of defined objects to be measured and/or

a particular measurement path for each of the defined objects to be measured, including two or more measurement paths each accounting to a type of measurement sensor the object is measurable with, and/or

the demanded position and/or the demanded orientation on the base corresponding to the object to be measured.

34. The coordinate measuring machine according to claim 33, wherein the object-determination functionality comprises a step of identifying the object located in the measuring volume by comparing the surface data with the set of object data, wherein the controlling information is generated providing the measurement path for the identified object as a function of a particular set of object data which corresponds to the identified object.

35. The coordinate measuring machine according to claim 30, wherein on execution of the object-determination functionality

the camera is realigned depending on the controlling information,

a second or more images are captured,

the surface data is updated by additionally using data derived by image processing of the second or more images and

the controlling information is actualized depending on the updated surface data.

36. The coordinate measuring machine according to claim 30, wherein the camera is built as a non-range-measuring camera and/or the camera is built as a camera for capturing visually perceivable 2D-images as CCD or CMOS-Array or webcam, and/or the camera comprises integrated illumination source for illuminating the measuring volume and/or the object.

37. The coordinate measuring machine according to claim 25, wherein a digital model of the object is generated on basis of the image data on basis of the surface data or the 3D-positions of the target points.

38. The coordinate measuring machine according to claim 25, wherein the frame structure comprising at least a first and a second frame member and a vertical rod, wherein the first and the second frame member and the vertical rod are arranged for being moveable in at least two perpendicular directions by at least two drive mechanisms, wherein the coordinate measuring machine is built as portal coordinate measuring machine.

39. The coordinate measuring machine according to claim 25, wherein the first camera or an additional camera is provided on the first or second frame member and/or is adapted to be directed to the base, wherein additional images and additional image data are provided by the additional camera.

40. The coordinate measuring machine according to claim 25, wherein the first camera or a range camera is

provided in an area close to the probe head, and

adapted to be directed to the base, and provided in a rotatable manner and capable to be directed to the moving direction of the probe head and/or being adapted to be moved synchronously with the probe head, and/or

the first or the range camera is alignable by position variation of at least one of the frame members and/or by variation of a capturing direction of the camera by swiveling a camera objective relative to a camera base.

41. The coordinate measuring machine according to claim 30, wherein the frame structure and/or the probe head comprises at least one receptacle for carrying at least the first camera, wherein the at least one receptacle and the first camera are built so that the first camera is modularly linkable to the at least one receptacle and modularly releasable from the at least one receptacle.

42. The coordinate measuring machine according to claim 41, wherein the coordinate measuring machine comprises a tool-exchange unit adapted for carrying the first camera and/or a measuring sensor, wherein at least the first camera and/or the measuring sensor is

modularly mountable at the tool-exchange unit and/or

automatically displaceable from the at least one receptacle to the tool-exchange unit and vice versa depending on measurement requirements derived from the image data.

43. The coordinate measuring machine according to claim 25, wherein the controller is adapted:

to set up a movement path of the probe head on the basis of the image data and/or

to control the movement path of the probe head via the drive mechanism on the basis of the image data, wherein the movement path represents the measurement path.

44. A coordinate measuring machine for determining at least one spatial coordinate of a measurement point of an object to be measured, comprising:

a base,

a drive mechanism adapted to drive a probe head in a manner such that the probe head is capable to move relative to the base for approaching a measurement point,

a first range camera having a range image sensor with a sensor array, wherein the range camera is adapted to be directed to a user of the coordinate measuring machine to take a sequence of user range images, and

a controller, adapted to control the drive mechanism on the basis of changes of a current user range image to one or more of preceding user range images.

45. The coordinate measuring machine according to claim 44, wherein a point cloud of the object and/or CAD-data of the object are provided to the user using

a hologram provided by a three-dimensional display, or

a virtual reality provided by VRgoggles.

46. The coordinate measuring machine according to claim 44, wherein a predetermined zone in the range image corresponding to a predetermined space in the user area is defined as control zone, and the controller is adapted to ignore changes of the current range image outside of the predetermined zone.

47. The coordinate measuring machine according to claim 44, wherein a predetermined sequences of changes corresponding to predetermined movements of a user are stored in a map in advance, and the controller controls the drive mechanism and/or one or more of the range cameras to perform an action assigned to the respective sequence of changes.

48. The coordinate measuring machine for determining at least one spatial coordinate of a measurement point of an object to be measured, comprising:

a base,

a drive mechanism adapted to drive a probe head in a manner such that the probe head is capable to move relative to the base for approaching a measurement point,

at least one range camera having a range image sensor with a sensor array,

a first range camera adapted to be directed to the object for providing a range image of the object, and

a controller, adapted to control the drive mechanism on the basis of the 3D-positions of the target points and/or on the basis of changes of a current user range image to one or more of preceding user range images,

wherein range pixels of the range image are used for deriving a point cloud with 3D-positions of target points of the object, and

wherein the first range camera or a second range camera is adapted to be directed to a user of the coordinate measuring machine to take a sequence of user range images.