Coordinate measuring apparatus

Abstract

Provided is a coordinate measuring device capable of measuring a workpiece in a position and posture deviated from a movable range of a contact probe. The coordinate measuring device includes a main body, a table, an angle meter, a 3-axis translation mechanism, a contact probe, a measurement setting unit, a measurement control unit, and a measurement unit. When a measurement start instruction is received, the measurement control unit controls movement of the contact probe by the 3-axis translation mechanism in accordance with the measurement setting to move the contact probe to the measurement position, and controls a rotation angle of the table in such a manner that the measurement position is disposed within the measurement space.

Description

Technical Field

[0001] This invention relates to a coordinate measuring device. Background Technology

[0002] Coordinate measuring devices that measure the shape of a workpiece, including its dimensions, positional relationships, contour shape, and geometric tolerances, by bringing a contact probe into contact with any measurement position on the workpiece to be measured and obtaining the coordinates of that measurement position, have been put into practical use (for example, see Patent Document 1).

[0003] Existing technical documents

[0004] Patent documents

[0005] Patent Document 1: European Patent Application Publication No. 2788714 Summary of the Invention

[0006] The problem the invention aims to solve

[0007] However, in conventional coordinate measuring devices, the size and shape of the workpiece are limited to the range of motion within the probe head. Furthermore, while increasing the range of motion can accommodate larger workpieces, this sometimes leads to larger devices and restricts installation space.

[0008] In view of the above-mentioned problems, the present invention aims to provide a coordinate measuring device capable of measuring the position and orientation of a workpiece that is outside the movable range of a contact probe.

[0009] Solution for solving the problem

[0010] The coordinate measuring apparatus of the present invention comprises: a main body; a stage connected to the main body in a manner rotatable relative to the main body; a protractor for detecting the rotation angle of the stage relative to the main body; a three-axis translation mechanism connected to the main body; a contact probe capable of moving within a measuring space along each axis of the three-axis translation mechanism; a non-contact optical sensor for acquiring map data within the measuring space; a measuring setting unit for setting measuring settings, wherein the measuring settings include determining the measuring position of a measuring element for the shape of a workpiece as the measuring object, and measuring items using the measuring element; a measuring control unit, which, upon receiving a measuring instruction, acquires the map data from the non-contact optical sensor, and, according to the map data and the measuring settings, controls the movement of the contact probe via the three-axis translation mechanism to move the contact probe to the measuring position, and controls the rotation angle of the stage such that the measuring position is configured within the measuring space; and a measuring unit for performing a measurement based on the measuring position measured by the contact probe and the measuring items using the measuring element.

[0011] Furthermore, other features, elements, steps, advantages, and characteristics become clearer through the following detailed description and the accompanying drawings.

[0012] The effects of the invention

[0013] According to the present invention, a coordinate measuring device is provided that can measure the position and orientation of a workpiece that is outside the movable range of a contact probe. Attached Figure Description

[0014] Figure 1 This is a diagram showing the overall structure of the coordinate measuring device.

[0015] Figure 2 This is a diagram illustrating a structural example of a non-contact optical sensor.

[0016] Figure 3 This is a diagram showing the system structure of the coordinate measuring device.

[0017] Figure 4 This is a flowchart illustrating an example of a measurement setup.

[0018] Figure 5 This is a flowchart illustrating an example of continuous measurement.

[0019] Figure 6 This is a schematic side view of the coordinate measuring device when the workpiece is in its initial position.

[0020] Figure 7 This is a top view of the platform when the workpiece is in its initial position.

[0021] Figure 8 This is a top view of the coordinate measuring device when the workpiece is located within the measuring space.

[0022] Figure 9 This is a top view of the platform when the workpiece is being measured within the measurement space.

[0023] Figure 10 This is a flowchart illustrating the process of setting the rotation angle.

[0024] Figure 11 This is a top view of the platform when the workpiece is in its initial position.

[0025] Figure 12 This is a top view of the platform when the workpiece is in the first position.

[0026] Figure 13 This is a top view of the platform when the workpiece is in the second position. Detailed Implementation

[0027] <Coordinate measuring device (overall structure)>

[0028] Figure 1 This is a diagram showing the overall structure of the coordinate measuring device 100. The coordinate measuring device 100 measures the dimensions, positional relationships, contour shape, and geometric tolerances of the workpiece W with high precision by placing a contact probe against any measurement position on the workpiece W to be measured and acquiring the three-dimensional coordinates of that measurement position. In addition to recording the measurement data of the workpiece W, the coordinate measuring device 100 can also calculate various values ​​through various operations. As described in this figure, the coordinate measuring device 100 includes a PC (Personal Computer) 1 and a main body 5.

[0029] PC1 can be understood as the control unit of the coordinate measuring device 100. PC1 can be either a laptop or a desktop. PC1 can also be connected to a mouse 2 as a user input device. The user input device can also be a keyboard, touchpad, touch panel, or stylus, etc.

[0030] The main body 5 comprises a head housing 57, a head 50, a contact probe 60, a non-contact optical sensor 31, a teaching pen 23, a teaching camera 21, a stage 70, a control console 11, and a remote control 25 as its main components.

[0031] The head housing 57 is a base that supports the head 50, the teaching camera 21, and the stage 70. For example, the head housing 57 has a ground contact portion 57a ​​and an upright portion 57b. The ground contact portion 57a ​​can be understood as a base plate that supports the stage 70 from below, i.e., a pedestal. The upright portion 57b can be understood as a column that stands upright from the ground contact portion 57a ​​and supports the head 50 and the teaching camera 21 respectively. The PC1 can be connected to the head housing 57 via a communication cable 3. A measurement button 80, a detection button 81, and a power button 82 may also be provided on the front part of the ground contact portion 57a.

[0032] When the measurement button 80 is pressed, a scan is performed by the non-contact optical sensor 31 to detect the position and posture of the workpiece and determine the measurement position for the workpiece. When the measurement button 81 is pressed, a scan is performed by the non-contact optical sensor 31, and based on a comparison with the acquired map data described later, the corresponding workpiece setting file is selected from multiple pre-registered setting files. The measurement position can be defined as the position where the contact probe 60 contacts the workpiece W. When the power button 82 is pressed, the main body 5 is switched on / off.

[0033] The head 50 can be understood as a three-axis translation mechanism that moves the contact probe 60 along the X-axis drive direction 51, the Y-axis drive direction 53, and the Z-axis drive direction 55. When described according to this figure, the head 50 includes an X-axis drive unit 52, a Y-axis drive unit 54, and a Z-axis drive unit 56.

[0034] The X-axis drive unit 52 is disposed at the upper end of the head housing portion 57, particularly the upright portion 57b. The X-axis drive unit 52 cantilever supports the Y-axis drive unit 54 in a manner that allows it to move freely along the X-axis drive direction 51. The X-axis drive unit 52 can be understood as a so-called translation beam. The Y-axis drive unit 54 supports the Z-axis drive unit 56 in a manner that allows it to move freely along the Y-axis drive direction 53. The Y-axis drive unit 54 can be understood as a so-called translational body. The Z-axis drive unit 56 supports the contact probe 60 in a manner that allows it to move freely along the Z-axis drive direction 55. The Z-axis drive unit 56 can be understood as a so-called translational rod.

[0035] The contact probe 60 can be understood as a contact element that contacts the workpiece W, i.e., a touch probe. The contact probe 60 can move within the measurement space along each drive axis of the head 50, specifically along the X-axis, Y-axis, and Z-axis. The measurement space can be understood as the space within which the contact probe 60 can move and perform measurements via the head 50. That is, the measurement space can also be understood as the range of movement of the contact probe 60. Furthermore, the contact probe 60 has a two-axis rotation mechanism connected to the head 50, and its posture when in contact with the workpiece W can be changed. As described in this figure, the contact probe 60 includes a B-axis drive unit 62, an A-axis drive unit 64, a stylus 65, and a workpiece camera 66.

[0036] The B-axis drive unit 62 is supported at the lower end of the Z-axis drive unit 56. The B-axis drive unit 62 supports the A-axis drive unit 64 in a manner that allows it to rotate freely along the B-axis drive direction 61. The B-axis drive direction 61 can be understood as a circumferential direction with the B-axis as the central axis. The B-axis can also be an axis parallel to the Z-axis. The A-axis drive unit 64 is supported by the B-axis drive unit 62. The A-axis drive unit 64 can also be understood as a component of the B-axis drive unit 62. The A-axis drive unit 64 supports the stylus 65 and the workpiece camera 66 in a manner that allows them to rotate freely along the A-axis drive direction 63. The A-axis drive direction 63 can be understood as a circumferential direction with the A-axis as the central axis. The A-axis can also be an axis on the XY plane that is uniquely determined by the displacement (height) of the Z-axis drive unit 56 and uniquely determined by the displacement (rotation angle) of the B-axis drive unit 62.

[0037] Furthermore, the B-axis drive unit 62 and the A-axis drive unit 64 can be understood as a 2-axis rotation mechanism connected to the head 50. The 2-axis rotation mechanism can change the posture of the contact probe 60, specifically, it can change the posture of the stylus 65 and the workpiece camera 66.

[0038] That is, in the coordinate measuring device 100 of this embodiment, the position of the contact probe 60 is determined by a 3-axis translation mechanism, and the posture of the contact probe 60 is determined by a 2-axis rotation mechanism. Furthermore, the posture of the contact probe 60 can also be understood as the angle of the stylus 65 determined by the 2-axis rotation mechanism, in other words, as the extension direction of the stylus 65.

[0039] In this way, the contact probe 60 employs a structure that allows the stylus 65 to rotate freely via a two-axis rotation mechanism, a so-called free-angle structure. Therefore, unlike conventional structures that only allow discrete angle adjustments, the angle of the stylus 65 can be continuously and steplessly adjusted. Furthermore, unlike conventional structures, with the free-angle structure, calibration is not required for each discrete angle adjustment.

[0040] The stylus 65 is a needle-shaped member supported on the A-axis drive unit 64. The front end of the stylus 65 may, for example, be machined into a spherical shape. In this case, the action of "making the contact probe 60 contact the workpiece W" can be understood as the action of "making the ball provided at the front end of the stylus 65 contact the workpiece W".

[0041] The workpiece camera 66 is a camera device supported on the A-axis drive unit 64. The workpiece camera 66 can also be understood as a component of the A-axis drive unit 64. The workpiece camera 66 is capable of capturing images of the mounting stage 70 and the workpiece W placed on the mounting stage 70 in an orientation determined by the 2-axis rotation mechanism.

[0042] The non-contact optical sensor 31 is a sensor that acquires three-dimensional point clouds, or so-called map data, within the measurement space. The non-contact optical sensor 31 can also be composed of a profilometer, a 2D camera, or both. As shown in this figure, the non-contact optical sensor 31 can also be mounted on the Y-axis drive unit 54. In this case, the non-contact optical sensor 31 can move arbitrarily within the measurement space along the X-axis and Y-axis. For example, by scanning while moving the non-contact optical sensor 31 along the X-axis drive direction 51, a three-dimensional point cloud within the measurement space can be acquired. The non-contact optical sensor 31 can also be understood as a component of the Y-axis drive unit 54. The structure and measurement principle of the non-contact optical sensor 31 will be described later.

[0043] The teaching pen 23 is one of the instruments used by the user during direct teaching of the measured position. The teaching pen 23 can be understood as a marker probe separately from the contact probe 60. The teaching pen 23 includes, for example, a stylus 24 and multiple optical markers 27.

[0044] The stylus 24 is a needle-shaped component supported at the front end of the teach pen 23. The front end of the stylus 24 may, for example, be machined into a spherical shape. In this case, the action of "bringing the teach pen 23 into contact with the workpiece W" can be understood as the action of "bringing the ball located at the front end of the stylus 24 into contact with the workpiece W". Multiple optical marks 27 are provided at different locations on the teach pen 23.

[0045] The teaching camera 21 can be understood as an optical measuring device that captures images of multiple optical marks 27 set on the teaching pen 23 and determines the position and orientation of the teaching pen 23. The teaching camera 21 may, for example, be supported near the upper end of the head housing 57, particularly the upright portion 57b, in an orientation that includes the entire measuring space in the coordinate measuring device 100 within the camera's field of view. The teaching camera 21 may also include an illumination unit 22 for illuminating the camera's field of view. The teaching camera 21 may also be provided separately from the non-contact optical sensor 31 and the workpiece camera 66. The teaching camera 21 can also be understood as one of the constituent elements of the head housing 57.

[0046] The stage 70 includes a disk-shaped stage for placing the workpiece W, and an θ-axis drive mechanism for rotating the stage along the θ-axis drive direction 71. The θ-axis drive direction 71 can be understood as a circumferential direction with the θ-axis as the central axis. The θ-axis can also be an axis parallel to the Z-axis.

[0047] Even if the measurement position on the workpiece W is outside the measurement space, the stage 70 can still rotate and move the workpiece W about the θ axis in a way that brings the measurement position into the measurement space. That is, the measurement space in which the contact probe 60 can move is different from the actual measurable range including the stage 70. Furthermore, when the stage 70 is driven along the θ axis, the three-dimensional coordinates in the device coordinate system in the measurement space can be converted into three-dimensional coordinates in a virtual global coordinate system by taking into account the displacement (rotation angle) of the stage 70 in the θ-axis driving direction 71.

[0048] The control console 11 can be understood as a user input device that accepts manual operations on the head 50 and the contact probe 60. For example, the control console 11 may also be provided with multiple joysticks that accept manual operations on each of the six axes (X-axis, Y-axis, Z-axis, A-axis, B-axis, and θ-axis). In addition, the control console 11 may also be provided with at least one of the aforementioned measurement button 80, detection button 81, and power button 82. The head housing 57 and the control console 11 can be connected via a communication cable 12.

[0049] The remote controller 25 is one of the user input devices used for direct teaching of the measurement position. The remote controller 25 may also be equipped with a trigger button 26 that accepts decision operations regarding the measurement position made via the teaching pen 23. Additionally, the remote controller 25 may also be equipped with at least one of the aforementioned measurement button 80, detection button 81, and power button 82. The PC1 and the remote controller 25 can be connected via a communication cable 4.

[0050] <Non-contact optical sensors>

[0051] Figure 2 This is a diagram illustrating a structural example of a non-contact optical sensor 31. The non-contact optical sensor 31 of this structural example can be understood as a profilometer. As described in this figure, the non-contact optical sensor 31 includes a laser emitter 32, a light-receiving lens 33, and an image sensor 34.

[0052] The laser emitting unit 32 irradiates a strip of laser light L onto the surface of the workpiece W, which is the object of measurement. The laser emitting unit 32 may also include a Powell lens as a unit for extending the laser L into a strip shape. Using a Powell lens is effective in ensuring uniform extension of the incident laser light. Alternatively, the laser emitting unit 32 may include a cylindrical lens as a unit for extending the laser L into a strip shape. Using a cylindrical lens is effective in reducing aberrations caused by the light wavelength. As described in this figure, the laser L extends into a strip shape with the Y-axis driving direction 53 as its long side. The light-receiving lens 33 images the light diffusely reflected from the surface of the workpiece W onto the imaging surface of the imaging unit 34. The larger the aperture of the light-receiving lens 33, the greater the amount of light received in the imaging unit 34. The imaging unit 34 generates imaging data corresponding to the image on the imaging surface. The cross-sectional shape, or so-called profile, of the workpiece W is acquired through imaging.

[0053] For example, during the measurement setup and continuous measurement described later, the non-contact optical sensor 31 moves along the X-axis driving direction 51, that is, in the direction intersecting the long side of the laser L which extends into a strip, while sequentially generating image data. Through scanning in this manner, the contours of each cross-section of the workpiece W are sequentially acquired along the moving direction of the non-contact optical sensor 31. By synthesizing this sequentially acquired contour data by the continuous measurement unit 113 described later, a three-dimensional point cloud corresponding to the position and shape of the workpiece W can be obtained. Furthermore, the three-dimensional point cloud generated by scanning using the non-contact optical sensor 31 can also be understood as the aforementioned map data.

[0054] <Coordinate Measuring Device (System Structure)>

[0055] Figure 3This is a diagram showing the system structure of the coordinate measuring device 100. In this diagram, the main components of the coordinate measuring device 100 are depicted as follows: PC1, mouse 2, console 11, teaching pen 23, remote control 25, head housing 57, X-axis drive unit 52, Y-axis drive unit 54, Z-axis drive unit 56, θ-axis drive unit 58, and contact probe 60. The components that appear are labeled with [reference to other components]. Figure 1 and Figure 2 Same reference numerals as shown in the attached figures.

[0056] PC1 executes PC application 111 via a CPU (not shown) to function as, for example, a measurement setting unit 112, a continuous measurement unit 113, and a communication / control unit 114. PC1 also includes memory 115 for storing PC application 111 and setting files. Memory 115 can be an HDD (Hard Disk Drive), SSD (Solid State Drive), or cloud storage device, etc.

[0057] The measurement setting unit 112 performs measurement settings for the workpiece W. The measurement settings may include, for example, the measurement position required to determine the measurement elements and measurement items for the shape of the workpiece W, which is the object of measurement; the posture of the contact probe 60 relative to the measurement position; and the measurement items using the measurement elements. In other words, the measurement settings can be understood as a general term for settings related to the measurement of the workpiece W. The content of the measurement settings may also be stored as a measurement setting file in the memory 115.

[0058] The shape of workpiece W can be defined as information related to the shape of workpiece W contained in the three-dimensional data included in the measurement setting file. When the three-dimensional data is a workpiece model generated by CAD (Computer-Aided Design), the outline, position, and orientation of the workpiece model in the CAD coordinate system are included in the information related to the shape of workpiece W. Alternatively, when the three-dimensional data is pre-measured data, the outline, position, and orientation of workpiece W in the global coordinate system or device coordinate system obtained through pre-measurement are included in the information related to the shape of workpiece W. Basic measurement elements can include geometric shapes such as planes, lines, points, circles, cylinders, cones, or spheres. Measurement items can include the dimensions of each measurement element, such as distances or angles between measurement elements. Furthermore, the measurement position and orientation measured by the contact probe 60, the measurement elements formed through each measurement, and the measurement items using the measurement elements can also be registered in the measurement setting file.

[0059] In particular, the measurement setting unit 112 can arbitrarily and easily set the measurement position where the contact probe 60 contacts the workpiece W, the posture of the contact probe 60 at the measurement position, and the measurement path of the contact probe 60 to the measurement position by direct teaching through the teaching pen 23 and the remote controller 25. The measurement setting of the workpiece W will be described in detail later.

[0060] The continuous measurement unit 113 performs continuous measurement of the workpiece W based on the measurement position measured by the contact probe 60 and the measurement items using the measurement elements. For example, the continuous measurement unit 113 calculates a first measurement element and a second measurement element based on the measurement position measured by the contact probe 60, and measures the dimension between the first measurement element and the second measurement element based on the measurement items. The continuous measurement of the workpiece W will be described in detail later. The measurement position and measurement elements can also be determined based on the aforementioned measurement setting file. In addition, the continuous measurement unit 113 generates a three-dimensional point cloud corresponding to the position and shape of the workpiece W by synthesizing the contour data sequentially acquired by the non-contact optical sensor 31.

[0061] The communication / control unit 114 controls the communication between PC1 and head housing 57, and the communication between PC1 and remote controller 25.

[0062] The head housing 57 includes a main control unit 121, an X-axis encoder unit 122, a θ-axis encoder unit 123, and a teaching camera 21.

[0063] The main control unit 121 controls the head housing 57, X-axis drive unit 52, Y-axis drive unit 54, Z-axis drive unit 56, θ-axis drive unit 58, and contact probe 60 according to instructions from users received by PC1 or console 11.

[0064] For example, the main control unit 121 functions as a measurement control unit that, upon receiving a measurement instruction, performs movement and posture control of the contact probe 60 according to a measurement setting file stored in the memory 115. As described with reference to this figure, the main control unit 121 controls the movement of the contact probe 60 using the X-axis drive unit 52, Y-axis drive unit 54, and Z-axis drive unit 56, which are equivalent to a 3-axis translation mechanism, to move the contact probe 60 to the measurement position. Furthermore, the main control unit 121 performs posture control of the contact probe 60 relative to this measurement position using the B-axis drive unit 62 and A-axis drive unit 64, which are equivalent to a 2-axis rotation mechanism. Moreover, the aforementioned measurement instruction can be defined as a trigger command for reading the measurement setting file and initiating the measurement of the workpiece W.

[0065] The main control unit 121 includes a communication unit 124. The communication unit 124 communicates with the console 11, the teaching camera 21, the X-axis drive unit 52, the θ-axis drive unit 58, the X-axis encoder unit 122, and the θ-axis encoder unit 123.

[0066] The X-axis encoder unit 122 obtains the displacement of the X-axis drive unit 52 in the X-axis drive direction 51, i.e., the X coordinate of the contact probe 60 in the device coordinate system, by reading the linear scale of the X-axis drive unit 52. The θ-axis encoder unit 123 obtains the displacement (rotation angle) of the stage 70 in the θ-axis drive direction 71 by reading the rotation scale of the θ-axis drive unit 58. That is, the θ-axis encoder unit 123 is an example of a protractor. Alternatively, a protractor capable of obtaining the rotation angle can be used instead of the θ-axis encoder unit 123.

[0067] In addition to the aforementioned illumination unit 22, the teaching camera 21 also includes an image capture unit 125 and a communication / control unit 126. The image capture unit 125 captures images of the plurality of optical marks 27 disposed on the teaching pen 23. The communication / control unit 126 controls the communication between the teaching camera 21 and the main control unit 121.

[0068] The X-axis drive unit 52 includes a communication / control unit 131. The communication / control unit 131 controls the communication between the X-axis drive unit 52 and the head housing unit 57, and the communication between the X-axis drive unit 52 and the Y-axis drive unit 54.

[0069] The Y-axis drive unit 54 includes a communication / control unit 141, a Y-axis encoder unit 142, a Z-axis encoder unit 143, and a non-contact optical sensor 31. The communication / control unit 141 controls the communication between the Y-axis drive unit 54 and the X-axis drive unit 42, and the communication between the Y-axis drive unit 54 and the Z-axis drive unit 56. Furthermore, the communication / control unit 141 also communicates with the Y-axis encoder unit 142, the Z-axis encoder unit 143, and the non-contact optical sensor 31.

[0070] The Y-axis encoder unit 142 obtains the displacement of the Y-axis drive unit 54 in the Y-axis drive direction 53, i.e., the Y coordinate of the contact probe 60 in the device coordinate system, by reading the linear scale of the Y-axis drive unit 54. The Z-axis encoder unit 143 obtains the displacement of the Z-axis drive unit 56 in the Z-axis drive direction 55, i.e., the Z coordinate of the contact probe 60 in the device coordinate system, by reading the linear scale of the Z-axis drive unit 56.

[0071] In addition to the aforementioned laser emitting unit 32 and imaging unit 34, the non-contact optical sensor 31 also includes a contour calculation unit 144 and a communication / control unit 145. The contour calculation unit 144 calculates the cross-sectional shape of the workpiece W, i.e., the so-called contour data, based on the imaging data sequentially acquired by the imaging unit 34. The continuous measurement unit 113 generates three-dimensional data based on this contour data. This structure reduces the computational load on the contour calculation unit 144 of the non-contact optical sensor 31. Alternatively, the contour calculation unit 144 can generate a three-dimensional point cloud based on the contour data; in this case, the measurement processing of the continuous measurement unit 113 and the three-dimensional point cloud generation processing can be performed in parallel. The communication / control unit 145 controls the communication between the non-contact optical sensor 31 and the communication / control unit 141.

[0072] The Z-axis drive unit 56 includes a communication / control unit 151. The communication / control unit 151 controls the communication between the Z-axis drive unit 56 and the Y-axis drive unit 54, and the communication between the Z-axis drive unit 56 and the contact probe 60.

[0073] The contact probe 60 includes a communication / control unit 161, a B-axis encoder unit 162, a camera unit 163, and a B-axis drive unit 62. The communication / control unit 161 controls communication between the contact probe 60 and the Z-axis drive unit 56. Furthermore, the communication / control unit 161 also communicates with the B-axis encoder unit 162, the camera unit 163, and the B-axis drive unit 62. The B-axis encoder unit 162 obtains the displacement (rotation angle) of the B-axis drive unit 62 in the B-axis drive direction 61 by reading the rotation scale of the B-axis drive unit 62. The camera unit 163 captures an image of an optical mark (not shown) provided on the A-axis drive unit 64. Based on the captured image pattern of the optical mark, the position and orientation of the A-axis drive unit 64 with the optical mark attached can be detected, thereby detecting the position and orientation of the stylus 65 supported on the A-axis drive unit 64.

[0074] The B-axis drive unit 62 includes a communication / control unit 164 and an A-axis encoder unit 165. The communication / control unit 164 communicates with the communication / control unit 161 of the contact probe 60. Additionally, the communication / control unit 164 also communicates with the A-axis encoder unit 165 and the A-axis drive unit 64. The A-axis encoder unit 165 obtains the displacement (rotation angle) of the A-axis drive unit 64 in the A-axis drive direction 63 by reading the rotation scale of the A-axis drive unit 64.

[0075] In addition to the aforementioned workpiece camera 66, the A-axis drive unit 64 also includes a communication / control unit 166, a Hall sensor unit 167, and an illumination unit 168. The communication / control unit 166 communicates with the communication / control unit 164 of the B-axis drive unit 62. Furthermore, the communication / control unit 166 also communicates with the Hall sensor unit 167, the illumination unit 168, and the workpiece camera 66. The Hall sensor unit 167 generates a detection signal corresponding to the displacement of the stylus 65 relative to the A-axis drive unit 64. The illumination unit 168 illuminates an optical mark (not shown) provided on the A-axis drive unit 64 from the back.

[0076] The workpiece camera 66 includes a camera unit 169. The camera unit 169 may also include photoelectric conversion elements such as a CCD (Charge Coupled Device) sensor or a CMOS (Complementary Metal Oxide Semiconductor) sensor.

[0077] <System Actions>

[0078] Next, while referring to Figure 3 A brief explanation of the system operation of the coordinate measuring device 100 is given.

[0079] For example, during direct teaching of the measurement position, a decision operation for the measurement position is performed using the teaching pen 23 and the remote control 25. More specifically, with the stylus 24 of the teaching pen 23 in contact with the measurement position of the workpiece W, the trigger button 26 of the remote control 25 is pressed. At this time, the camera command is transmitted through the signal path from the remote control 25 via the communication / control unit 114 of the PC1 and the communication unit 124 of the main control unit 121 to the communication / control unit 126 of the teaching camera 21.

[0080] The teaching camera 21 receives the recording command and controls the illumination unit 22 and the camera unit 125 to record images of multiple optical marks 27 set on the teaching pen 23. The recording data acquired by the camera unit 125 is transmitted through a signal path from the camera unit 125 via the communication / control unit 126 of the teaching camera 21 and the communication unit 124 of the main control unit 121 to the communication / control unit 114 of the PC1. The PC1 analyzes the recording data to determine the measurement position indicated by the teaching pen 23.

[0081] Additionally, for example, when scanning using the non-contact optical sensor 31, the scanning command is transmitted via a signal path from the communication / control unit 114 of PC1 through the communication unit 124 of the main control unit 121, the communication / control unit 131 of the X-axis drive unit 52, and the communication / control unit 141 of the Y-axis drive unit 54 to the communication / control unit 145 of the non-contact optical sensor 31.

[0082] The non-contact optical sensor 31 receives the scanning command and controls the laser emitting unit 32 to irradiate a strip of laser L toward the surface of the workpiece W, which is the object of measurement. At this time, the imaging unit 34 receives the reflected light from the workpiece W and generates imaging data corresponding to the image on the imaging surface. In addition, the X-axis drive unit 52 receives the scanning command and moves the non-contact optical sensor 31 along the X-axis drive direction 51.

[0083] By scanning in this way, a contour corresponding to the position and shape of the workpiece W can be acquired in the contour calculation unit 144. This contour is transmitted through a signal path from the communication / control unit 145 of the non-contact optical sensor 31, via the communication / control unit 141 of the Y-axis drive unit 54, the communication / control unit 131 of the X-axis drive unit 52, and the communication unit 124 of the main control unit 121, to the communication / control unit 114 of the PC1. The PC1 detects the position and orientation of the workpiece W placed on the mounting stage 70 by analyzing this contour.

[0084] Additionally, for example, when using the contact probe 60 to perform point measurement, the lighting command is transmitted through a signal path from the communication / control unit 114 of the PC1 via the communication unit 124 of the main control unit 121, the communication / control unit 131 of the X-axis drive unit 52, the communication / control unit 141 of the Y-axis drive unit 54, the communication / control unit 151 of the Z-axis drive unit 56, the communication / control unit 161 of the contact probe 60, the communication / control unit 164 of the B-axis drive unit 62, and the communication / control unit 166 of the A-axis drive unit 64 to the lighting unit 168.

[0085] The illumination unit 168 receives the illumination command and illuminates an optical mark (not shown) provided on the A-axis drive unit 64 from the back. The imaging unit 163 of the contact probe 60 receives the transmitted light from the optical mark when the contact probe 60 contacts the workpiece W, and generates imaging data corresponding to the image on the imaging surface. This imaging data is transmitted via a signal path from the communication / control unit 161 of the contact probe 60, through the communication / control unit 151 of the Z-axis drive unit 56, the communication / control unit 141 of the Y-axis drive unit 54, the communication / control unit 131 of the X-axis drive unit 52, and the communication unit 124 of the main control unit 121, to the communication / control unit 114 of the PC1.

[0086] Furthermore, when performing point measurement using the contact probe 60, at the moment the contact probe 60 contacts the workpiece W, the displacement amounts in each of the X-axis drive directions 51, 53, 55, and 71 are transmitted from the X-axis encoder 122, Y-axis encoder 142, Z-axis encoder 143, and θ-axis encoder 123 to the communication / control unit 114 of the PC1. Based on the aforementioned camera data and the displacement amounts in each axis drive direction, the PC1 calculates the three-dimensional coordinates of the measurement position.

[0087] Furthermore, the aforementioned camera unit 163, X-axis encoder unit 122, Y-axis encoder unit 142, Z-axis encoder unit 143, and θ-axis encoder unit 123 receive inputs from essentially different clocks and do not operate synchronously. Therefore, in order to accurately determine the three-dimensional coordinates of the measurement position, synchronous detection is preferable to ensure that the timing of the contact probe 60 contacting the workpiece W does not deviate from the timing of referencing the camera data and the displacement in each axis drive direction.

[0088] <Measurement Setup>

[0089] Figure 4 This is a flowchart illustrating an example of measurement setting performed by the measurement setting unit 112. This process can also be started, for example, by pressing the measurement setting button displayed on the PC1's screen as a GUI (Graphical User Interface).

[0090] When this process begins, in step S11, the workpiece W, which is the object of the measurement setting, is placed on the stage 70. At this time, the contact probe 60 can also be moved to a position where the workpiece camera 66 can face the stage 70 from directly above. In addition, in this step S11, it can also be specified whether the rotation of the stage 70 is enabled during measurement. When the rotation of the stage 70 is disabled, the measurement is performed within the measurement space of the coordinate measuring device 100, that is, within the movement range of the contact probe 60.

[0091] Next, in step S12, a three-dimensional point cloud is acquired by sequentially generating camera data while moving the non-contact optical sensor 31 along the X-axis driving direction 51. Furthermore, in step S13, unwanted point clouds other than the workpiece W are deleted from the acquired three-dimensional point cloud. Unwanted point clouds to be deleted can be, for example, those whose height relative to the surface of the stage 70 is below a predetermined threshold. Through steps S12 and S13, a three-dimensional point cloud corresponding to the position and shape of the workpiece W can be acquired.

[0092] Next, in step S14, the retraction boundary is adjusted. The retraction boundary can be understood as the boundary that allows the contact probe 60 to move without contacting the workpiece W during automatic measurement. The retraction boundary is defined by including the area of ​​the workpiece W. The shape of the retraction boundary can be, for example, a cuboid or a cylinder. Various parameters of the retraction boundary, such as the longitudinal length, transverse length, and height of a cuboid, or the base radius and height of a cylinder, or the rotation angles of each of the three axes, can be manually input. Alternatively, the various parameters of the retraction boundary can be automatically input by setting the allowance distance between the probe and the workpiece W.

[0093] Next, in step S15, pattern registration is performed. For example, the three-dimensional point cloud acquired in step S13 is converted into height data, and any feature region in this height data is registered as pattern data. The registered pattern data is processed as reference data containing information related to the shape of the workpiece W. Furthermore, the shape of the workpiece W in this process refers to the shape of the workpiece W itself, which is placed for the purpose of measurement.

[0094] If a pattern is registered beforehand, even if the workpiece W, the object of measurement, is configured in a different position and posture than when the measurement was set, the position will still be aligned to ensure consistency with the registered pattern. In this step, the position alignment method, the area to be registered as a pattern, the search range during position alignment, exclusion areas, and critical areas can also be set. The area to be registered as a pattern can be either the entire workpiece W or a part of the workpiece W.

[0095] Next, in step S16, the workpiece camera 66 takes a full-circle photograph of the workpiece W from all 360° directions around it. During this full-circle photograph, for example, the workpiece camera 66, positioned to view the platform 70 from a slightly upward angle, can continuously photograph the workpiece W during one full rotation of the platform 70. By taking a full-circle photograph of the workpiece W beforehand, the user can confirm the location of the measurement positions, measurement elements, and measurement items specified in steps S17 and S18 on the workpiece W through the workpiece image on the GUI.

[0096] Next, in step S17, the position is taught. For example, direct teaching can also be performed using the teaching pen 23 and the remote control 25. In this case, with the stylus 24 of the teaching pen 23 in contact with the position of the workpiece W, the trigger button 26 of the remote control 25 is pressed.

[0097] By repeating this operation, arbitrary measurement elements can be temporarily determined. For example, if any face of workpiece W is set as a measurement element, any three points belonging to that face can be designated as measurement positions. Alternatively, for example, if any edge of workpiece W is set as a measurement element, the face to which that edge belongs can be designated using the aforementioned method, and then any two points belonging to that edge can be designated as measurement positions.

[0098] After temporarily determining the measurement elements, a single-piece measurement begins with the pressing of the measurement start button in the GUI, performed by the contact probe 60. This single-piece measurement refers to measuring the placed workpiece W before the measurement settings are saved. During direct teaching, the measurement settings for workpiece W can be implemented through a single-piece measurement of workpiece W.

[0099] In the single-piece measurement of workpiece W, the contact probe 60 can be inserted into the aforementioned retraction boundary in the same posture as the teaching pen 23 during teaching, and the contact probe 60 can be brought into contact with workpiece W at the measurement position specified during teaching. After completing the point measurement in this way, the contact probe 60 can be removed from the retraction boundary along the opposite path to its entry. Furthermore, outside the retraction boundary, since there is no risk of collision between the contact probe 60 and workpiece W, the contact probe 60 can move freely in its posture and along its path. In addition, outside the retraction boundary, the contact probe 60 can move at a higher speed than inside the retraction boundary. The measurement path of the contact probe 60, i.e., the sequence and route of the point measurements, can also be automatically set to efficiently traverse multiple specified measurement positions.

[0100] Next, in step S18, the measurement items are registered. As measurement items, distances and angles between measurement elements can also be registered.

[0101] Finally, in step S19, the above series of settings are saved as a measurement setting file in memory 115. It is also possible to save multiple measurement setting files in advance for each type of workpiece W that is the object of measurement.

[0102] Furthermore, this process is basically applicable to measurement settings performed using physical equipment with coordinate measuring device 100, i.e., online measurement settings. Therefore, the above series of descriptions envisions a scenario in which measurement settings including measurement positions, measurement elements, and measurement items are performed within the measurable range including the stage 70.

[0103] However, this process can also be applied to measurement settings performed using equipment other than the physical coordinate measuring device 100, i.e., offline measurement settings. In this case, the measurement settings, including measurement positions, measurement elements, and measurement items, are performed outside the measurable range of the coordinate measuring device 100. For example, a dedicated measurement setting device equipped with a stage, teaching pen, and teaching camera can be prepared separately from the coordinate measuring device 100. Furthermore, in offline measurement settings, to avoid inconsistencies in the coordinate systems between the coordinate measuring device 100 and the dedicated measurement setting device, the three-dimensional coordinates obtained in the dedicated measurement setting device can be converted into three-dimensional coordinates on a virtual global coordinate system.

[0104] <Continuous Measurement>

[0105] Figure 5 This is a flowchart illustrating an example of continuous measurement performed by the continuous measurement unit 113.

[0106] In step S21, the workpiece W, which is to be measured, is placed on the stage. Next, in step S22, a registered measurement setting file is arbitrarily read from the memory 115. The user can select the file to use from the registered measurement setting files on the GUI of the PC application displayed on the PC1's monitor. Alternatively, by pressing the detection button 81, map data can be acquired by the non-contact optical sensor 31, and a suitable measurement setting file for the workpiece W can be automatically determined and read by comparing the shape data of the placed workpiece W in the map data with the three-dimensional shape data of the workpiece contained in the registered measurement setting file.

[0107] For example, the measurement setting file can be determined by matching the shape data of the workpiece W contained in the map data with the shape data contained in the measurement setting file. By having the user select the measurement setting file on the PC application, the action of pressing the detection button 81 and the scanning action of the non-contact optical sensor 31 can be omitted. The aforementioned method of determining the measurement setting file by pattern matching is effective when the measurement setting file to be used is known. In the method of using the detection button 81, since the measurement setting file to be used can be determined simply by pressing the detection button 81, it is effective when the measurement setting file to be used is unknown.

[0108] In step S23, it is determined whether a measurement start instruction has been given by the continuous measurement unit 13. The measurement start instruction is given by pressing the measurement button 80. Alternatively, the measurement start instruction can be given via the GUI of the PC application. If a measurement start instruction has been given, the process proceeds to step S24 and continuous measurement begins. Otherwise, if no measurement start instruction has been given, the process returns to step S23.

[0109] Furthermore, the order of steps S21 to S23 in this process can be interchanged. For example, after reading the measurement setting file in step S22, the workpiece W can be placed on the stage 70 in step S12, and the measurement can begin after confirming the measurement start instruction in step S23. Alternatively, the workpiece W can be placed on the stage 70 and the measurement setting file can be read after confirming the measurement start instruction. In this case, a display can be shown on the PC1's screen to prompt the user to place the workpiece W on the stage 70 and select the measurement setting file. Furthermore, if the non-contact optical sensor scans map data by pressing the detection button 81, the scanning performed by the non-contact optical sensor after the measurement start instruction is confirmed can be skipped.

[0110] Then, in step S24, the acquisition of a three-dimensional point cloud by the non-contact optical sensor 31 and the deletion of unwanted point clouds are performed sequentially. As a result, a three-dimensional point cloud corresponding to the position and shape of the workpiece W can be acquired.

[0111] Next, in step S25, a comparison is performed with the registered pattern. Specifically, the 3D point cloud acquired in step S24 is converted into height data, and a data portion matching the registered pattern is searched from this height data. Through this search process, the position and orientation of the workpiece W placed on the stage 70 are calculated.

[0112] The computational processing in step S25 is equivalent to aligning the coordinate system related to the map data acquired by the non-contact optical sensor 31 with the coordinate system related to the shape of the workpiece W, which is the object of measurement. Here, the coordinate system related to the map data can be understood as the coordinate system of the map data acquired by the non-contact optical sensor 31. On the other hand, the coordinate system related to the shape of the workpiece W can be understood as the coordinate system of the three-dimensional data contained in the measurement setting file.

[0113] Furthermore, the map data acquired by the non-contact optical sensor 31 includes first information related to the position and orientation of the workpiece W placed on the stage 70. On the other hand, the three-dimensional data included in the measurement setting file includes second information related to the position and orientation of the workpiece W, which is pre-registered as a pattern, i.e., reference data. Therefore, the two coordinate systems can be matched based on the first and second information to align the position of the workpiece W.

[0114] Alternatively, step S25 can also be understood as 3D position and pose matching. This 3D position and pose matching is used to match the degrees of freedom of the five axes (X-axis, Y-axis, Z-axis, A-axis and B-axis) based on the 3D position and pose of the workpiece W on the map data obtained by the non-contact optical sensor 31 and the 3D position and pose of the workpiece W on the reference data registered in the measurement setting file.

[0115] Next, in step S26, based on the position and posture of the workpiece W, the measurement position where the contact probe 60 contacts the workpiece W, the posture of the contact probe 60 at the measurement position, and the measurement path of the contact probe 60 to reach the measurement position are calculated again.

[0116] Next, in step S27, point measurements are sequentially performed by the contact probe 60 along the measurement path specified in the measurement setting file. Specifically, the contact probe 60 is moved toward the measurement position in a predetermined posture, and the three-dimensional coordinates of the contact position are acquired at the point in time when the contact probe 60 contacts the workpiece W.

[0117] Alternatively, contour measurement can be performed in step S27. Contour measurement is also known as scanning measurement or scanning-type measurement. In contour measurement, from a first measurement position corresponding to the starting point to a second measurement position corresponding to the ending point, the contact probe 60 is moved while maintaining contact between the tip of the stylus 65 and the workpiece W, thereby continuously acquiring three-dimensional coordinates along the shape of the workpiece W.

[0118] Finally, in step S28, the measurement results are displayed in the GUI. The measurement results may include not only the measured values ​​of the measured items, but also, for example, a judgment flag (OK / NG) indicating whether the measured values ​​are within the normal range.

[0119] In the coordinate measuring device 100, steps S24 to S28 described above are performed automatically. That is, the user can continuously perform three-dimensional measurement of the workpiece W simply by performing the actions from step S21 to step S23.

[0120] Furthermore, this process can also be applied to the case where multiple identical workpieces W are placed on the mounting stage 70 in step S21, i.e., when multiple workpieces W are measured in batches. In this case, in steps S24 and S25, the position and orientation of each of the multiple workpieces W are calculated by comparing them with the registered pattern.

[0121] Then, in step S26, based on the respective positions and orientations of the multiple workpieces W, the measurement positions where the contact probe 60 contacts each of the multiple workpieces W, the orientation of the contact probe 60 at those measurement positions, and the measurement path of the contact probe 60 to reach those measurement positions are calculated again. Here, the measurement path of the contact probe 60 can also be automatically set to most efficiently circulate among the multiple measurement positions specified for each of the multiple workpieces W.

[0122] <Platform 70>

[0123] Figure 6 This is a schematic side view of the coordinate measuring device 100 when the workpiece W is in the initial position Psn. Figure 7 This is a top view of the stage 70 when the workpiece W is in the initial position Psn. Figure 8 This is a top view of the coordinate measuring device 100 when the measuring position Pn of workpiece W is within the measuring space Msr. Figure 9 This is a top view of the stage 70 when the measurement position Pn of workpiece W is within the measurement space Msr. Figures 6-9 In the diagram, the measurement space Msr is represented by a dashed line, and the scanning area Scn of the non-contact optical sensor 31 is represented by a single-dot dashed line.

[0124] The non-contact optical sensor 31 causes a laser L, which extends in a strip shape with the Y-axis driving direction 53 as its long side, to move along the X-axis and irradiate the target area. The area irradiated by the laser L is the scanning area. That is, as shown... Figure 6 , Figure 7 As shown, the scanning area Scn is rectangular when viewed from the Z-axis driving direction 55. Furthermore, the entire stage 70 is positioned inside the scanning area Scn. Therefore, when the workpiece W is placed on the stage 70, the non-contact optical sensor 31 can acquire map data of the workpiece W. Additionally, by varying the width of the laser L according to the illumination position in the X-axis driving direction, the scanning area Scn can also take a shape other than a rectangle when viewed from the Z-axis driving direction.

[0125] In the coordinate measuring device 100, the measuring space Msr does not cover the entire stage 70. That is, depending on the position and orientation of the workpiece W placed on the stage 70, the measuring position Pn on the workpiece W is within the scanning area Scn, but sometimes deviates from the measuring space Msr. In such cases, the θ-axis drive mechanism of the θ-axis drive unit 58 is driven, and the stage 70 rotates along the θ-axis drive direction 71.

[0126] As a result, the measurement position Pn on the workpiece W moves to the interior of the measurement space Msr (refer to...). Figure 8 , Figure 9(etc.). In this way, the workpiece W placed on the stage 0 can be measured in a small measurement space Msr, and the coordinate measuring device 100 can be miniaturized. In addition, if the workpiece W is placed on the stage 70, the workpiece W can be measured regardless of its position and orientation. Therefore, the user's operation is simplified during continuous measurement. That is, the user's convenience can be improved.

[0127] The rotation angle of the stage 70 can also be a predetermined angle. Alternatively, the rotation angle can be set such that the measurement position Pn of the workpiece W is contained within the measurement space Msr. In this case, the rotation angle is set in a way that minimizes the rotation angle while containing the measurement position Pn within the measurement space Msr.

[0128] Furthermore, the coordinate system of the map data and the coordinate system containing the measurement space Msr (e.g., the device coordinate system) can be a common coordinate system (e.g., the global coordinate system) or they can be different coordinate systems. The three-dimensional coordinates of the map data are transformed to match the device coordinate system containing the measurement space Msr.

[0129] For example, in the coordinate measuring device 100, even if the stage 70 rotates, the Z-coordinate does not change. Therefore, the coordinate change caused by rotation occurs in both the X and Y coordinates. Specifically, the following method can be used: converting the X and Y coordinate data of the measuring position into R and θ coordinate data, adjusting the coordinate data of the measuring position after movement according to the rotation angle, and then converting it back into X and Y coordinate data. Furthermore, in the case of a change in the Z-coordinate, a transformation for the Z-coordinate is also performed. However, this coordinate transformation method is only one example and is not limited to the transformation method described above.

[0130] Furthermore, when multiple measurement positions are set on the workpiece W, the rotation angle of the stage 70 is set in such a way that all measurement positions are included within the measurement space Msr. Next, the setting of the rotation angle of the stage 70 will be explained with reference to the accompanying drawings.

[0131] Figure 10 This is a flowchart illustrating the process of setting the rotation angle. Furthermore, Figure 10 The flowchart shown is a replacement Figure 5 The flowchart shown is set up according to steps S25 and S26.

[0132] First, in step S31, based on the comparison between the first information of the map data and the second information of the measurement setting data in step S24, it is determined whether there is a measurement position located outside the measurement space Msr at the current position of the workpiece W. If the determination is "yes", the process proceeds to step S32. Conversely, if the determination is "no", the process proceeds to step S38.

[0133] In steps S32 and S33, the rotation direction of the stage 70, i.e., clockwise CW or counterclockwise CCW, and the rotation angle are determined. The rotation direction and rotation angle of the stage 70 are determined in a way that maximizes the entry of the measurement position into the measurement space Msr with the minimum rotation angle.

[0134] The rotation angle and rotation direction can be determined as follows. Figure 11 This is a top view of the mounting stage 70 when the workpiece W is in the initial position Ptn. (Example) Figure 11 As shown, a first measurement position Pn1, a second measurement position Pn2, a third measurement position Pn3, a fourth measurement position Pn4, a fifth measurement position Pn5, a sixth measurement position Pn6, and a seventh measurement position Pn7 are set on the workpiece W, which is the object of measurement. Furthermore, [the following is a continuation of the previous sentence, which is not directly related to the previous sentence]... Figure 11 The position of workpiece W shown is set as the initial position Ptn. That is, when the measurement of workpiece W begins, workpiece W is at the initial position Ptn.

[0135] Then, in step S32, the coordinates of all measurement positions are obtained. Then, in step S33, while rotating the stage 70 clockwise CW, its rotation angle and the number of measurement positions retracted into the measurement space Msr are investigated. For example, imagine in Figure 11 The state shown is the state after the stage 70 is rotated clockwise CW. When the fourth measurement position Pn4 is taken into the measurement space Msr, in addition to the fifth measurement position Pn5, the sixth measurement position Pn6, and the seventh measurement position Pn7 which were originally in the measurement space, the fourth measurement position Pn4 is also taken into the measurement space. That is, all four measurement positions are taken into the measurement space Msr.

[0136] The workpiece W is positioned such that the measurement position within the measurement space Msr is the position where the maximum amount of measurement is achieved. Figure 12 At the first position Pt1 shown, the stage 70 is rotated clockwise CW. When it temporarily moves to the outside of the measurement space Msr at the fifth measurement position Pn5 and is then retracted into the measurement space Msr, the workpiece W moves to the first position Pt1. The workpiece W moves to the first position Pt1 by rotating the stage 70 clockwise CW by an angle θ1.

[0137] Conversely, the same method was used to study the case where the stage 70 rotates counterclockwise (CCW). This ensures that the workpiece W is at the position where the measurement space Msr is most fully recessed. Figure 13At the second position Pt2 shown. With the stage 70 rotated counterclockwise CCW, after being taken into the measurement space Msr immediately adjacent to the fourth measurement position Pn4, the workpiece W moves to the second position Pt2. When the stage 70 rotates by a rotation angle θ2, the workpiece W moves to the second position Pt2.

[0138] In step S33, the absolute value of rotation angle θ1 is compared with the absolute value of rotation angle θ2. Here, the absolute value of rotation angle θ2 is less than the absolute value of rotation angle θ1. Therefore, in step S33, the rotation direction in the first rotation is determined to be counterclockwise (CCW), and its rotation angle is determined to be rotation angle θ2.

[0139] In the coordinate measuring device 100 of this embodiment, the measurement position when the stage 70 is rotated can be accurately predicted based on the map data acquired by the non-contact optical sensor 31. Therefore, the rotation direction and rotation angle of the stage 70 can be optimized. Furthermore, the above-described determination method is one example, and other methods can also be used to obtain the optimal rotation direction and rotation angle of the stage 70. After step S33 is completed, the process proceeds to step S34.

[0140] In step S34, assuming the stage 70 has rotated, a determination is made as to whether there are measurement positions configured outside the measurement space Msr. If the determination is "yes," the process returns to step S32, and multiple rotation settings are determined by repeatedly performing steps S32 to S34 to ensure that all measurement positions are included within the measurement space Msr. If the determination is "no," the process proceeds to step S35. In step S35, the currently determined rotation drive sequence and the rotation settings associated with the rotation direction and angle are saved as a rotation setting file in memory 115. Then, the process proceeds to step S36.

[0141] In step S36, based on the position and orientation of the workpiece W and the position of the stage 70, the rotation direction, rotation angle, and number of rotations of the stage 70 are recalculated; the measurement position of the workpiece W when the stage 70 is rotated; the orientation of the contact probe 60 at that measurement position; and the measurement path of the contact probe 60 to reach that measurement position. Furthermore, when rotation of the stage 70 is not required, the operation of step S36 is the same as... Figure 5 The process is the same as step S25. Then, the process moves to step S37.

[0142] In step S37, the stage 70 is rotated along the θ-axis drive direction 71 based on the rotation setting file. Then, in step S38, point measurements using the contact probe 60 are performed sequentially along the measurement path specified in the measurement setting file. Furthermore, the point measurements performed using the contact probe 60 are related to... Figure 5 Step S26 of the process shown is the same, and detailed explanation is omitted.

[0143] Then, in step S39, it is determined whether the point measurement of all measurement positions has been completed. If the determination is "yes", the process proceeds to step S27, and the measurement results are displayed in the GUI. Otherwise, if the determination is "no", the process returns to step S37. Thus, the rotation of the stage 70 and the point measurement are repeated until the point measurement of all measurement positions is completed.

[0144] As described above, since the coordinate measuring device 100 has a stage 70, it can accurately measure the workpiece W in three dimensions even when there is a measuring position located outside the measuring space Msr. That is, the measuring space Msr may not cover the entire upper part of the stage 70, making the coordinate measuring device 100 smaller and lighter.

[0145] Furthermore, when the stage 70 rotates, the coordinate systems of the avoidance boundary and the workpiece camera's viewpoint are matched with the device coordinate system containing the measurement space Msr, respectively, based on the rotation angle of the stage 70. Additionally, when the stage 70 rotates at different angles, the coordinate system of the measured element is also matched with the device coordinate system containing the measurement space Msr, based on the rotation angle of the stage 70.

[0146] Furthermore, in the coordinate measuring device 100, the contact probe 60 can be used to measure the contact position of the workpiece W each time the stage 70 is rotated. This measures the three-dimensional coordinates at each measurement position, and the measured values ​​of the measured items are determined based on the measurement results. Moreover, by matching the measured values ​​of each measured item with a common coordinate system, a combination of measurement elements of the workpiece W can be obtained. Using this measurement method, the coordinate measuring device 100 can also measure workpieces W with sizes that cannot be completely contained within the measurement space Msr.

[0147] The rotation angle of the stage 70 is preferably set to minimize the number of rotations and the total movement of the stage 70 (the sum of the rotation angles). For example, it is possible that even if the maximum number of measurement positions are not included in the measurement space Msr during the first rotation, the total movement of the stage 70 (the sum of the rotation angles) is small at the point when the measurement of all measurement positions is completed.

[0148] <Direct teaching outside the Msr measurement space>

[0149] Sometimes, direct teaching is performed outside the measurement space Msr. In this case, similar to offline direct teaching performed by a dedicated measurement setup device, the coordinate system of the area where direct teaching was performed is matched with the device coordinate system containing the measurement space Msr. Furthermore, the portion outside the measurement space Msr can also be contained in the same device coordinate system as the device coordinate system containing the measurement space Msr.

[0150] <Variation Example>

[0151] For example, consider the following variation: by combining the posture control functions of the rotatable stage 70 and the contact probe 60 as shown in the above embodiment, the side profile of the workpiece W can be measured efficiently. This variation is particularly effective in measuring the roundness or cylindricity of workpieces W that have a cylindrical shape or other shapes of revolution.

[0152] The main control unit 121 controls the B-axis drive unit 62 and the A-axis drive unit 64 to change the posture of the stylus 65 of the contact probe 60, causing the stylus 65 to tilt relative to the vertical direction (Z-axis direction), for example, to orthogonal to a roughly horizontal direction. This allows the tip of the stylus 65 to contact the side of the workpiece W from the normal direction of the side surface. The main control unit 121 also functions as a measurement control unit.

[0153] Next, the main control unit 121 controls the X-axis drive unit 52, the Y-axis drive unit 54 and the Z-axis drive unit 56 to make the front end of the stylus 65, whose posture has been changed, contact the measurement start point on the side of the workpiece W on the stage 70A.

[0154] In this state, the main control unit 121 controls the θ-axis drive unit 58 to rotate the stage 70 within a predetermined angle range. At this time, the continuous measurement unit 113 acquires the coordinates of the contact position of the stylus 65, which changes as the stage 70 rotates. Methods for acquiring these coordinates include, for example, contour measurement (scanning measurement) and multi-point measurement.

[0155] During contour measurement, the main control unit 121 controls the position of the contact probe 60 while maintaining the position of the stylus 65 in contact with the side of the workpiece W, and continuously rotates the stage 70. The continuous measurement unit 113 continuously acquires the three-dimensional coordinates of the contact probe 60 and the rotation angle of the stage 70 during this period, and generates continuous contour data of the side of the workpiece W.

[0156] In multi-point measurement, the main control unit 121 causes the stage 70 to rotate intermittently at a predetermined angle each time, and stops at each rotation position. At each stop position, the contact probe 60 contacts the side of the workpiece W and performs point measurement to obtain its coordinates. By repeating this operation, coordinate data of multiple measurement points on the side of the workpiece W are obtained.

[0157] Then, the continuous measurement unit 113 calculates geometric tolerances such as roundness, cylindricity, coaxiality, and eccentricity of the side surface of the workpiece W based on the contour data or coordinate data of multiple measurement points obtained through these measurements. According to this measurement method, the shape of the rotating body can be measured at high speed and with high precision by utilizing the rotation of the stage 70 without large movement of the contact probe 60 in the XYZ directions.

[0158] Furthermore, in the above embodiment, a structure is illustrated in which the contact probe 60 is supported from above by a vertical translation rod 56, but the structure of the present invention is not limited to this. For example, although not shown, a structure in which the contact probe approaches the workpiece W from the side can also be used.

[0159] As an example, the horizontally extending arm is supported in a manner that allows it to move relative to the column (corresponding to the upright portion 57b) extending vertically from the base portion 57a ​​in both the vertical direction (Z-axis direction) and the horizontal direction (X-direction). In this structure, by incorporating a rotatable stage 70 in the same manner as in the second embodiment, the measurement of a cylindrical workpiece W can be performed efficiently.

[0160] When performing measurements using this structure, the measurement control unit 121 first moves the arm along the Z-axis to determine the desired measurement height. Next, the contact probe is moved along the X-axis to contact the side of the workpiece W. In this state, while rotating the stage 70 around the θ-axis, contour measurement or multi-point measurement is performed. This allows for the measurement of the roundness, cylindricity, etc., of the workpiece W. This structure is particularly effective as a device specifically designed for measuring workpieces with shaft shapes.

[0161] Another example of posture detection for the contact probe 60 will be described. In the above embodiment, the camera unit 163 captures an image of an optical mark (not shown) provided on the A-axis drive unit 64. The position and posture of the A-axis drive unit 64 with the optical mark attached can be detected based on the captured image pattern of the optical mark, and further, the position and posture of the stylus 65 supported on the A-axis drive unit 64 can be detected. However, the posture detection of the contact probe 60 is not limited to this. An A-axis encoder unit 165 and a B-axis encoder unit 162 may also be provided to detect the rotation angles of the A-axis drive unit 64 and the B-axis drive unit 62, which control the posture of the contact probe 60. These can be general encoders such as optical encoders, magnetic encoders, or electrostatic capacitive encoders that read a rotating scale. Alternatively, an absolute encoder that detects the absolute position of the rotation angle or an incremental encoder that detects the amount of rotation from the origin may be used. The rotation angle (posture) information detected by these encoders is used by the measurement and control unit 121 to control the posture of the contact probe 60.

[0162] The above embodiments are illustrative of the present invention, and the present invention is not limited to the above embodiments. It can be implemented in various ways without departing from the spirit of the present invention. For example, the constituent elements described in each embodiment may be appropriately combined or some may be omitted.

[0163] Explanation of reference numerals in the attached figures

[0164] 1: PC

[0165] 2: Mouse

[0166] 3: Communication cable (between the head housing and the PC)

[0167] 4: Communication cable (between remote control and PC)

[0168] 5: Main Body

[0169] 11: Console

[0170] 12: Communication cable (between console and head housing)

[0171] 21: Teaching Camera

[0172] 22: (Lighting section of the teaching camera)

[0173] 23: Demonstration pen

[0174] 24: (of the teaching pen) stylus

[0175] 25: Remote Control

[0176] 26: Trigger Button

[0177] 27: (The optical markings of the teaching pen)

[0178] 31: Non-contact optical sensor

[0179] 32: Laser light-emitting part

[0180] 33: Light-receiving lens

[0181] 34: (Non-contact optical sensor) Camera section

[0182] 50: Head

[0183] 51: X-axis drive direction

[0184] 52: X-axis drive unit

[0185] 53: Y-axis drive direction

[0186] 54: Y-axis drive unit

[0187] 55: Z-axis drive direction

[0188] 56: Z-axis drive unit

[0189] 57: Head shell section

[0190] 57a: Ground contact part

[0191] 57b: Erect part

[0192] 58: θ-axis drive unit

[0193] 60: Contact probe

[0194] 61: B-axis drive direction

[0195] 62: B-axis drive unit

[0196] 63: A-axis drive direction

[0197] 64: A-axis drive unit

[0198] 65: (Contact probe) stylus

[0199] 66: Workpiece Camera

[0200] 70: Platform

[0201] 71: θ-axis driving direction

[0202] 80: Measurement Button

[0203] 81: Detection button

[0204] 82: Power button

[0205] 100: Coordinate measuring device

[0206] 111: PC Applications

[0207] 112: Measurement and Setting Section

[0208] 113: Continuous Measurement Section

[0209] 114: Communications / Control Department

[0210] 115: Memory

[0211] 121: Main Control Unit

[0212] 122: X-axis encoder section

[0213] 123: θ-axis encoder section

[0214] 124: Ministry of Communications

[0215] 125: (The camera section of the teaching camera)

[0216] 126: (Teaching camera) Communication / Control Unit

[0217] 131: (X-axis drive unit) Communication / control unit

[0218] 141: (Y-axis drive unit) Communication / control unit

[0219] 142: Y-axis encoder section

[0220] 143: Z-axis encoder section

[0221] 144: Contour Calculation Department

[0222] 145: (Communication / Control Unit for Non-Contact Optical Sensors)

[0223] 151: (Z-axis drive unit) Communication / control unit

[0224] 161: (Contact probe) Communication / Control Unit

[0225] 162: B-axis encoder section

[0226] 163: (The camera section that contacts the probe)

[0227] 164: (B-axis drive unit) Communication / control unit

[0228] 165: A-axis encoder section

[0229] 166: (A-axis drive unit) Communication / control unit

[0230] 167: Hall Sensor Section

[0231] 168: (Illumination unit of A-axis drive section)

[0232] 169: (Workpiece camera) Camera section

[0233] L: Laser

[0234] W: Workpiece

Claims

1. A coordinate measuring device, comprising: main body; A stage that is connected to the main body in a manner that allows it to rotate relative to the main body; An angle meter that detects the rotation angle of the stage relative to the main body; A 3-axis translation mechanism, which is connected to the main body; The contact probe is capable of moving within the measurement space along each axis of the three-axis translation mechanism; The measurement setting unit sets measurement settings, wherein the measurement settings include a measurement position for determining the measurement element for the shape of the workpiece being measured, and a measurement item using the measurement element. The measurement control unit, upon receiving a measurement start instruction, controls the movement of the contact probe via the 3-axis translation mechanism according to the measurement settings, so that the contact probe moves to the measurement position, and controls the rotation angle of the stage in such a way that the measurement position is positioned within the measurement space; and The measurement unit performs measurements based on the measurement location determined by the contact probe and the measurement items using the measurement elements.

2. The coordinate measuring device according to claim 1, further comprising: A non-contact optical sensor acquires map data within the measurement space; and The coordinate system matching unit, based on the map data and the shape of the workpiece being measured, matches the coordinate system related to the measurement data with the coordinate system related to the shape of the workpiece being measured. The measurement control unit controls the movement of the contact probe based on the coordinate system matched by the coordinate system matching unit, so that the contact probe moves to the measurement position and controls the rotation angle of the stage.

3. The coordinate measuring device according to claim 1, wherein, When at least the measurement position is outside the measurement space, the measurement control unit controls the rotation angle of the stage in such a way that the measurement position is moved into the measurement space.

4. The coordinate measuring device according to claim 1, wherein, It also includes a memory that stores the measurement positions of the measurement elements for determining the shape of the workpiece, as well as the measurement settings. The measurement setup includes measurement items that use the measurement elements.

5. The coordinate measuring device according to claim 1, wherein, When the rotation angle of the stage is changed, the measurement control unit matches the coordinate system of the measurement position with the coordinate system of the measurement space based on the rotation angle of the stage. The measuring unit performs measurements using a contact probe based on a coordinate system matched by the measuring control unit.

6. The coordinate measuring device according to claim 1, wherein, When performing measurements between the measurement elements, the measurement control unit matches the coordinate systems between the measurement elements. The measuring unit performs measurements using a contact probe based on a coordinate system matched by the measuring control unit.

7. The coordinate measuring device according to claim 1, wherein, The contact probe also features: The A-axis drive unit supports the stylus so that it can rotate freely along the A-axis drive direction, wherein the A-axis drive direction is the drive direction centered on the A-axis, which extends in a direction intersecting the normal to the upper surface of the stage. The B-axis drive unit supports the stylus so that it can rotate freely along the B-axis drive direction, wherein the B-axis drive direction is the drive direction centered on the B-axis extending along the normal to the upper surface of the stage.

8. The coordinate measuring device according to claim 1, wherein, The measurement setting unit includes: A marking probe, which is equipped with optical markings and is separately positioned from the contact probe; and An optical measuring device is used to photograph the optical mark and determine the position and orientation of the mark probe. The acquisition of the measurement settings in the measurement setting unit can be performed outside the measurement space.

9. The coordinate measuring device according to claim 1, wherein, It also includes a workpiece camera, which is capable of capturing images of the camera range associated with the measurement space. When the measurement control unit changes the rotation angle of the stage, it makes the coordinate system of the camera's field of view match the coordinate system of the measurement space.

10. The coordinate measuring device according to claim 1, wherein, The measuring unit calculates a first measuring element and a second measuring element based on the measuring position measured by the contact probe, and measures the dimension between the first measuring element and the second measuring element based on the measuring item.

11. The coordinate measuring device according to claim 2, wherein, The non-contact optical sensor includes a light-emitting unit capable of illuminating light that extends in a band-like pattern along a direction intersecting the vertical direction. The stage is housed within the scanning area of ​​the non-contact optical sensor. A portion of the stage is retracted into the measurement space, and the entire upper surface of the stage is retracted into the measurement space by rotating the stage.

12. The coordinate measuring device according to claim 2, wherein, The non-contact optical sensor includes a light-emitting unit capable of illuminating light that extends in a band-like pattern along a direction intersecting the vertical direction. A portion of the stage is incorporated within the scanning area of ​​the non-contact optical sensor. A portion of the stage is retracted into the measurement space, and the entire upper surface of the stage is retracted into the measurement space by rotating the stage. The measurement and control unit can determine the position and posture of the workpiece based on a portion of the map data.

13. The coordinate measuring device according to claim 2, wherein, The measurement settings include reference data, which contains information related to the shape of the workpiece being measured. The measurement control unit performs pattern matching between the map data and the reference data, and calculates the correspondence between the measurement position included in the measurement settings and the coordinates of the current position on the workpiece being measured in the device coordinate system, and then determines the rotation angle of the platform.

14. The coordinate measuring device according to claim 2, wherein, Based on the map data, a retraction boundary is set that allows the contact probe to move without contacting the workpiece. When the measurement control unit changes the rotation angle of the stage, it matches the coordinate system of the retreat boundary with the coordinate system of the measurement space based on the rotation angle of the stage.

15. The coordinate measuring device according to claim 2, wherein, The measurement and control unit can determine the position and posture of the workpiece based on a portion of the map data.

16. The coordinate measuring device according to claim 15, wherein, The measurement control unit sets the smallest angle among the angles that allows the unmeasured measurement position located outside the measurement space to enter the measurement space to the maximum extent as the rotation angle.

17. The coordinate measuring device according to any one of claims 1 to 16, further comprising: A column, which extends vertically from the body and is fixedly disposed relative to the body; A translation beam is connected to the column at its upper part in a manner that allows it to translate in a first direction in the horizontal direction; A translational body, which is connected to the translation beam in a manner capable of translational movement relative to the translation beam in a second direction in the horizontal direction, wherein... The second direction is different from the first direction; as well as A translation rod is connected to the translation body in a manner that allows it to translate relative to the translation body in the vertical direction. The contact probe is connected to the translation rod.

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