Projection device and projection method

Abstract

Provided are a projection device and a projection method for assisting in measurement by a three-dimensional measuring machine. This projection method comprises: a step for generating, through use of a processing unit (102), measurement assistance images (AS1-AS2, SF1, P1-P3, H1-H2, A1-A2) corresponding to the contour or shape of a workpiece (W) installed in a measurement device (10), on the basis of the position and orientation of the workpiece (W); and a step for projecting the measurement assistance images (AS1-AS2, SF1, P1-P3, H1-H2, A1-A2) onto the workpiece (W) from a projection unit (50).

Description

Projection device and projection method

[0001] The present invention relates to a projection device and a projection method, and more particularly to a projection device and a projection method used for measuring objects (hereinafter referred to as "workpieces"), etc.

[0002] A coordinate measuring machine (CMM) measures the three-dimensional shape of a workpiece by moving a probe relative to the workpiece. The measurement data obtained from the workpiece measurement is calculated based on pre-set measurement coordinates to determine the three-dimensional shape of the workpiece.

[0003] Patent Document 1 discloses a method for setting measurement coordinates in a three-dimensional coordinate measuring machine. In the three-dimensional coordinate measuring machine described in Patent Document 1, measurement coordinates are automatically set based on measurement data obtained by measuring a plane and a hole.

[0004] Japanese Unexamined Patent Publication No. 7-128044

[0005] When performing measurements using a three-dimensional measuring machine, the operator must know in advance the positional reference point for the workpiece placed on the surface plate. If the operator is not proficient in measuring the workpiece's reference point, they may make mistakes in the workpiece's placement or orientation, leading to rework. Furthermore, if the workpiece's reference point is misidentified during manual alignment, the risk of accidents such as collisions between the measuring device and the workpiece increases when performing CNC (Computer Numerical Control) measurement.

[0006] To address the above issues, it is conceivable to regulate the workpiece placement using a workpiece placement jig. By using a workpiece placement jig to place the workpiece, the reproducibility of the workpiece's placement position and orientation can be ensured, thereby preventing rework and reducing the risks associated with the above-mentioned issues.

[0007] However, when using a jig for workpiece installation, it is necessary to fix the jig for workpiece installation to the three-dimensional measuring machine. Furthermore, it is necessary to prepare a dedicated jig for each workpiece. For this reason, there is a demerit that the versatility of the three-dimensional measuring machine is lost.

[0008] The present invention has been made in view of such circumstances, and an object thereof is to provide a projection device and a projection method for assisting measurement by a three-dimensional measuring machine.

[0009] The projection device according to the first aspect of the present invention includes a processing unit that generates a measurement support image corresponding to the contour or shape of a workpiece based on the position and orientation of the workpiece installed in the measurement device, and a projection unit that projects the measurement support image onto the workpiece.

[0010] The projection device according to the second aspect of the present invention is such that, in the first aspect, the processing unit generates a measurement support image using the relative position information between the measurement device and the projection unit.

[0011] The projection device according to the third aspect of the present invention is such that, in the first or second aspect, the processing unit generates a measurement support image that can distinguish a probing target location or a probed location from other locations.

[0012] The projection device according to the fourth aspect of the present invention is such that, in any one of the first to third aspects, the processing unit generates a measurement support image that indicates the contour structure of the workpiece.

[0013] The projection device according to the fifth aspect of the present invention is such that, in any one of the first to fourth aspects, the processing unit generates a measurement support image that indicates at least one of the surface of the measurement target of the workpiece, a point on the surface, and the contour of a hole formed in the workpiece.

[0014] The projection device according to the sixth aspect of the present invention is such that, in the fifth aspect, the processing unit generates a measurement support image that indicates the probing angle with respect to the hole formed in the workpiece.

[0015] A projection device according to the seventh aspect of the present invention, in any of the first to sixth aspects, includes an operation unit that receives input of an offset value for the installation position and orientation of a workpiece, and a processing unit adjusts the amount of movement and rotation of the measurement support image using the offset value.

[0016] An eighth aspect of the present invention is a projection method which includes the steps of generating a measurement support image corresponding to the contour or shape of a workpiece based on the position and orientation of the workpiece installed on the measuring device, and projecting the measurement support image onto the workpiece.

[0017] According to the present invention, a measurement support image corresponding to the contour or shape of the workpiece can be projected onto the workpiece, allowing the operator to easily confirm the measurement target area of ​​the workpiece.

[0018] This is a diagram (perspective view and block diagram) showing a three-dimensional measuring machine according to one embodiment of the present invention. This is an explanatory diagram for explaining the projector model. This is a data flow diagram showing the projection method according to the first embodiment. This is a diagram showing an example of a method for edge extraction. This is a diagram showing an example of projection of a measurement support image according to the first embodiment. This is a data flow diagram showing the projection method according to the second embodiment. This is a diagram showing an example of projection of a measurement support image according to the second embodiment. This is a diagram showing an example of projection of a measurement support image according to the second embodiment.

[0019] Embodiments of the present invention will be described below with reference to the attached drawings.

[0020] [Three-Dimensional Measuring Machine] Figure 1 is a diagram (perspective view and block diagram) showing a three-dimensional measuring machine according to one embodiment of the present invention.

[0021] As shown in Figure 1, the three-dimensional measuring machine 1 according to this embodiment includes a measuring device 10, a projection device 50, and a control device 100.

[0022] The measuring device 10 is a device (CMM) that measures the shape (contour) and dimensions of a workpiece W by bringing a measuring element 26, which is provided at the tip of a probe 22 (including a stylus 24), into contact with the workpiece W and scanning it.

[0023] The control device 100 controls the measuring device 10 to control the measurement of the workpiece W by the measuring device 10. The control device 100 receives operation input from the operator via the operation unit 110 and outputs commands to the measuring device 10 according to the operation input.

[0024] The projection device (projector) 50 is equipped with a light source 52 (for example, an LED (Light-Emitting Diode) light source or a laser light source) and a projection optical system 54, and projects an image (measurement support image) to support measurement onto the workpiece W placed on the surface plate 18 of the measuring device 10. The measurement support image is an image corresponding to the shape of the part to be measured on the workpiece W, and is in the CMM coordinate system Σ of the measuring device 10. Ｗ Based on this, each measurement target location is defined. Such measurement support images can be generated, for example, based on the CAD (Computer Aided Design) data of the workpiece W. For example, the measurement support images are pre-stored in the memory 104 of the control device 100 for each workpiece W. The operator can retrieve the measurement support image corresponding to the workpiece W by giving an instruction to the processing unit 102 via the operation unit 110 to specify the workpiece W to be used for measurement. Here, the projection device 50 is an example of a projection unit according to the present invention.

[0025] As an image projection method in the projection device 50, for example, projection mapping can be employed. Here, projection mapping refers to projecting an image onto the workpiece W that corresponds to the shape of the workpiece W. In the projection mapping according to this embodiment, for example, an image corresponding to the properties of the surface (e.g., flat or curved surface or inclination angle or curvature with respect to the surface plate 18, etc.) is projected onto the surface of the workpiece W, and an image corresponding to the properties of the structure is projected onto structures formed on the workpiece W (e.g., holes, protrusions or steps). More specifically, for holes, if it is difficult to illuminate the inner wall of the hole, an image showing the outline of the hole, etc., is projected. For protrusions and steps, an image showing their respective properties (e.g., shape, outline or dimensions, etc.) is projected. In addition to projection mapping, laser mapping may be employed as an image projection method, for example.

[0026] According to this embodiment, the projection device 50 can project an image onto the workpiece W to assist in measurement, allowing the operator to easily confirm the installation position and orientation of the workpiece W. This helps to prevent errors caused by misrecognition of the installation position or orientation of the workpiece W.

[0027] Furthermore, the projection device 50 is not limited to a single unit; multiple projection devices 50 may be installed to project images onto the workpiece W from multiple directions. Also, in the example shown in Figure 1, the projection device 50 is mounted on a tripod, separate from the measuring device 10, but the installation configuration of the projection device 50 is not limited to this. The projection device 50 may be installed, for example, on the ceiling, wall, or floor of the installation location of the measuring device 10, or it may be attached to the measuring device 10 (such as the surface plate 18).

[0028] (Measuring device) As shown in Figure 1, the measuring device 10 includes a base 20 and a surface plate 18 provided on the base 20. The surface 18A of the surface plate 18 is formed in a planar shape. The workpiece W is placed on the surface 18A of the surface plate 18. The workpiece W may be fixed to the surface 18A of the surface plate 18 using, for example, a clamping mechanism.

[0029] A pair of columns 16 are attached to the surface plate 18, extending upward from the surface 18A of the surface plate 18 in the figure. A beam 14 is spanned across the upper ends of the columns 16. The pair of columns 16 are movable synchronously on the surface plate 18, and the beam 14 is movable parallel to the surface 18A of the surface plate 18. A motor can be used as a driving means for moving the columns 16 relative to the surface plate 18. The pair of columns 16 may also be connected on the underside of the surface plate 18.

[0030] A head 12 is attached to the beam 14. The head 12 is movable along the length of the beam 14. A motor can be used as a driving means for moving the head 12 relative to the beam 14.

[0031] A probe 22 is attached to the lower end of the head 12 so as to be movable in the vertical direction shown in the figure. A motor can be used as a driving means for moving the probe 22 in the vertical direction.

[0032] The measuring device 10 includes a movement measurement unit (for example, a linear encoder) for measuring the amount of movement of the column 16, the head 12, and the probe 22, respectively.

[0033] The probe 22 includes a stylus 24, which is a highly rigid axial member. The material of the stylus 24 can be, for example, a superhard alloy, titanium, stainless steel, ceramic, or carbon fiber.

[0034] A measuring element 26 (probe sphere) is provided at the tip of the stylus 24 of the probe 22. The measuring element 26 is a spherical component with high hardness and excellent wear resistance. For example, ruby, silicon nitride, zirconia, ceramic, etc. can be used as the material for the measuring element 26. The diameter of the measuring element 26 is 4.0 mm in one example.

[0035] When measuring the workpiece W, the column 16, head 12, and probe 22 are moved to bring the measuring probe 26 into contact with the workpiece W. The measuring probe 26 is then scanned along the shape of the workpiece W, and the displacement of the measuring probe 26 is measured. This measured displacement data is transmitted to the control device 100. The control device 100 processes this data using a measurement program to determine the shape (contour) and dimensions of the workpiece.

[0036] (Control device) As shown in Figure 1, the control device 100 includes a processing unit 102 and a memory 104, and is connected to the measuring device 10 and the projection device 50 via a controller 106. The control device 100 may be configured as, for example, a personal computer or a workstation.

[0037] The processing unit 102 includes a processor (e.g., a CPU (Central Processing Unit)) that controls the operation of each part of the measuring device 10 and the control device 100. The processing unit 102 receives operation input from the operator via the operation unit 110. The processing unit 102 then transmits control signals corresponding to this operation input to each part of the measuring device 10, the projection device 50, and the control device 100 via the controller 106 to control the operation of each part. Here, the processing unit 102 functions as a projection control unit for controlling the projection device 50 and a measurement control unit for controlling the measurement of the workpiece W. For example, the processing unit 102 receives a designation of the workpiece W to be used for measurement in response to operation input from the operation unit 110, retrieves a measurement support image corresponding to the workpiece W from the memory 104, performs the calculations described later, and projects the measurement support image using the projection device 50.

[0038] The operation unit 110 includes an operating member that receives operation input from the operator. This operating member can be, for example, a keyboard for text input, a pointing device, a mouse, or a touch panel provided on the surface of the display unit 112.

[0039] The controller 106 is a means for communicating with the measuring device 10 and performs data conversion processing between the controller 10 and the measuring device 10. The controller 106 may include a D / A (digital-to-analog) converter for converting digital commands transmitted from the control device 100 to the measuring device 10 into analog signals, and an A / D (analog-to-digital) converter for converting data such as measured values ​​sent from the measuring device 10 to the control device 100 into digital data.

[0040] The memory 104 includes a storage device that stores a program used for calculations by the processing unit 102, and data such as measurement results obtained from the measuring device 10. As the memory 104, for example, a device including a magnetic disk such as an HDD (Hard Disk Drive) or a device including flash memory such as an SSD (Solid State Drive) can be used.

[0041] The display unit 112 is a device for displaying character information, images, GUIs (Graphical User Interfaces), etc. As the display unit 112, for example, a liquid crystal display can be used. Data such as measurement values acquired from the measuring device 10 may be displayed on the display unit 112.

[0042] [Projection Device] In this embodiment, when measuring the workpiece W using the measuring device 10, an image for assisting the operator's operation is projected onto the workpiece W by the projection device 50. In order to project an image according to the workpiece W, the CMM coordinate system Σ Ｗ of the measuring device 10 and the projector coordinate system Σ Ｐ of the projection device 50 need to be linked.

[0043] (Projector Model) FIG. 2 is an explanatory diagram for explaining the projector model.

[0044] As shown in FIG. 2, the CMM coordinate system Σ ｗ is a coordinate system set for the measuring device 10, with the origin being O ｗ and having three-dimensional orthogonal coordinate axes of X ｗ axis, Y ｗ axis, and Z ｗ axis. Note that in the example shown in FIG. 1, the origin O ｗ is set on the head 12, but it is not limited to this. For example, as long as the position (three-dimensional position) in the three-dimensional space to which the measuring device 10 belongs can be specified, any coordinate system may be used, or it may be set at the installation position of the workpiece W.

[0045] The projector coordinate system Σ Ｐ has the optical axis center O Ｐ of the projection optical system of the projection device 50 as the origin, with the right direction from the origin O Ｐ being the X Ｐ axis, the downward direction being the Y Ｐ axis, and the optical axis direction being the Z Ｐ axis, and is a three-dimensional orthogonal coordinate system.

[0046] The image coordinate system Σ ｓ has the origin O Ｐ of the projector coordinate system Σ Ｐ as the origin, and from Z​Ｐ Along the direction, the origin is the upper left of the screen IP at a focal distance f of the projection optical system of the projection device 50, X Ｐ Axis and Y Ｐ This is a two-dimensional Cartesian coordinate system (pixel coordinate system) with a U-axis and a V-axis running parallel to the other axes.

[0047] First, the CMM coordinate system Σ of point P, which indicates the target of the image projected by the projection device 50. ｗ Coordinates (x) ｗ , y ｗ , z ｗ The projector coordinate system Σ is determined using the rotation matrix R and translation vector t of the projection device 50, as shown in equation (1) below. Ｐ It can be converted to coordinates (x, y, z) in a given location.

[0048]

[0049] Here, [R|t] is the CMM coordinate system Σ ｗ From the projector coordinate system Σ Ｐ This is a transformation matrix (external parameter matrix) for coordinate transformation to the CMM coordinate system Σ ｗ This represents the orientation and position of the projection device 50 in [R|t]. １１ ,r １２ , ..., r ３３ ,t ｘ ,t ｙ ,t ｚ These are called external parameters of the projection device 50.

[0050] Next, the projector coordinate system Σ Ｐ If point P, located at (x, y, z) as viewed from the screen IP, has coordinates (pixel coordinates) of the projected point Q as (u, v), then the following relationships shown in equations (2) to (7) hold.

[0051]

[0052]

[0053]

[0054]

[0055]

[0056]

[0057] Here, (x', y') is the projector coordinate system Σ Ｐ This represents the coordinates of the projected point obtained by projecting point P, located at (x, y, z) as viewed from the image, onto the normalized image plane (z=1). Furthermore, (x'', y'') represents the coordinates of the projected point (distorted point) obtained by projecting point P onto the normalized image plane when lens distortion of the projection optical system of the projection device 50 is taken into consideration.

[0058] Also, yf ｘ , f ｙ This indicates the focal length in the x and y directions, expressed in pixels. Also, (c ｘ , c ｙ ) is the image coordinate system Σ ｓ This indicates the optical center (the position where the optical axis of the projection device 50 intersects with the screen IP, the optical center in pixel units). Also, k １ ,k ２ ,k ３ is the radial strain coefficient, and p １ , p ２ is the tangential distortion coefficient. In this embodiment, the focal length f ｘ , f ｙ , optical center c ｘ , c ｙ This is called an internal parameter of the projection device 50, and the distortion coefficient k １ ,k ２ ,k ３ , p １ , p ２ These are referred to as the distortion parameters of the projection device 50. The internal parameters and distortion parameters of the projection device 50 correspond to the "projector calibration information D50" described later. The internal parameters and distortion parameters are assumed to have been obtained in advance through calibration.

[0059] In the above projector model, CMM coordinate system Σ Ｗ Coordinates (x) ｗ , y ｗ , z ｗ By obtaining a pair (set) of the pixel coordinates (u, v) of the projection device 50, the CMM coordinate system Σ Ｗ and projector coordinate system ΣＰ It is possible to calculate the transformation matrix [R|t] (corresponding to the external parameters of the projection device 50) that links them.

[0060] The transformation matrix [R|t] corresponds to the "projector CMM relative position information D70" described later. The transformation matrix [R|t] is assumed to be acquired in advance before the calculations for projecting the measurement support image described later are performed.

[0061] [First Embodiment] In this embodiment, an image including the contour structure of the workpiece W is projected onto the workpiece W placed on the surface platen 18 of the measuring device 10 as a measurement support image, thereby enabling the operator to be alerted. Here, the image including the contour structure of the workpiece W may include, for example, images showing boundary representations, ridges, edges, or vertices (see Japanese Industrial Standard JIS B 3401: 1993).

[0062] Figure 3 is a data flow diagram showing the projection method according to the first embodiment.

[0063] First, the control device 100 acquires the CAD (Computer-Aided Design) model D10 and installation position and orientation information D30 of the workpiece W.

[0064] The workpiece CAD model D10 contains information including the three-dimensional shape of the workpiece W (for example, design information including the shape and dimensions of each part of the workpiece W).

[0065] The workpiece placement position and orientation information D30 is information that represents how the workpiece W is placed on the surface plate 18 (measuring station) of the measuring device 10, expressed through translation and rotation. For example, the workpiece placement position and orientation information D30 represents the placement position of the workpiece W on the surface 18A of the surface plate 18 (CMM coordinate system Σ) when measuring the workpiece W. ｗ Coordinates (in the CMM coordinate system Σ) and orientation (in the CMM coordinate system Σ) ｗ It includes information such as the rotation angle or tilt for each axis. The workpiece installation position and orientation information D30 can be obtained, for example, when a manual alignment of the workpiece W is performed during the process of creating a measurement program and trying out measurements using the measurement program.

[0066] In this embodiment, the workpiece CAD model D10 is moved and rotated based on the workpiece installation position and orientation information D30 acquired during the first measurement (S10). Furthermore, the contour structure (e.g., boundary representation, ridges, edges, or vertices) is extracted from the workpiece CAD model D10 (S12).

[0067] Note that the order of moving and rotating the workpiece CAD model D10 (S10) and extracting the contour structure (S12) may differ from the above.

[0068] Next, rendering (S14) is performed based on the contour structure extracted in S12 to generate a measurement support image with brightness and color corresponding to the contour structure of the workpiece W. Then, this measurement support image is projected from the projection device 50 onto the workpiece W on the surface plate 18 (S16). In step S16, for example, line segments having a predetermined brightness, color, and shape (thickness) along the ridges or edges of the workpiece W may be projected onto the workpiece W on the surface plate 18. Alternatively, an image having a predetermined brightness, color, and shape may be projected onto the vertices of the workpiece W.

[0069] When projecting the measurement support image, first, projector calibration information D50 is read from memory 104, and a projector model for rendering the measurement support image is defined (S50: see equations (1) to (7)). Then, based on the projector CMM relative position information D70 (transformation matrix [R|t]), the projector model is moved (translated) and rotated (S52), and the measurement support image is projected into the CMM coordinate system Σ ｗ From the projector coordinate system Σ Ｐ The coordinates are transformed. As a result, as described above, the measurement support image can be projected from the projection device 50 onto the workpiece W on the surface plate 18.

[0070] According to this embodiment, by projecting a measurement support image based on the position and orientation of the workpiece W during the first measurement onto the workpiece W on the surface plate 18 from the projection device 50, the operator can visually confirm whether the position and orientation of the workpiece W are the same as during the first measurement during subsequent measurements, or assist in aligning the position and orientation of the workpiece W (for example, matching it to the first measurement) without mechanical jigs.

[0071] Furthermore, according to this embodiment, even if the position of the workpiece W is changed during the second and subsequent measurements, CNC (Computer Numerical Control) measurement can be performed without manual alignment. Specifically, according to this embodiment, the installation position and orientation of the workpiece W recognized by the measuring device 10 can be projected onto the workpiece W in real time. Therefore, when it is necessary to move the position of the workpiece W for various reasons, an offset value is manually set (adjusted) by the operation unit 110 to the workpiece installation position and orientation information D30 held by the measuring device 10 so that the projection matches the moved workpiece W (S30). Then, in step S10, the amount of movement and rotation of the workpiece CAD model are adjusted according to this offset value (for example, the offset value is added to the amount of movement and rotation of the workpiece CAD model). As a result, even when the workpiece W is moved to a different position than in previous measurements, it becomes possible to project a measurement support image that matches the position and orientation of the workpiece W.

[0072] Examples of methods for extracting contour structure (edge ​​information, etc.) from the work CAD model D10 include the following (A) to (C).

[0073] (A) Method using the edge extraction function provided by the CAD software The workpiece CAD model D10 contains information about edges corresponding to the boundaries of surfaces or edges connecting vertices within the workpiece W. The control device 100 can extract this edge information to generate a measurement support image showing the contour structure.

[0074] (B) Inverted Hull Method First, the faces of the workpiece W in the workpiece CAD model D10 are divided into polygons (for example, triangles). Here, each polygon is assigned a normal vector that has its starting point on its surface and its ending point outside the object (workpiece W).

[0075] Next, each polygon is offset outside the workpiece W along its normal. Then, the normals of the offset polygons are reversed to generate a 3D model of the workpiece W with its front and back reversed.

[0076] The back (back side) of the 3D model of workpiece W, which has its front and back sides reversed (inverted model), is made invisible (transparent), and the inverted model and the original workpiece CAD model are rendered simultaneously. At this time, by rendering the original workpiece CAD model as a black body with reflectivity of 0 and the inverted model as a light-emitting body, it is possible to render particularly sharp contour images.

[0077] (C) Method for extracting edges from depth information after normal rendering As shown in Figure 4, in the rendering step (S14), the workpiece CAD model is coordinate-transformed to match the workpiece W on the surface platen 18, and depth information is obtained from the coordinate-transformed workpiece CAD model. Here, the depth information is information indicating the distance from the projection device 50 to each point on the surface of the workpiece W. The depth information is obtained, for example, based on the workpiece CAD model D10 and the projector CMM relative position information D70.

[0078] In the example shown in Figure 4, pixels with shallow depth information (closer to the projection device 50) have darker brightness, while pixels with deeper depth information (further from the projection device 50) have brighter brightness. The control device 100 extracts edges based on the amount of change in depth information (brightness) as described above.

[0079] For edge detection as described above, for example, the Canny method (see Canny, J., A computational approach to edge detection, IEEE Transactions on Pattern Analysis and Machine Intelligence, 8(6), 679-698, (1986)) can be applied.

[0080] According to the example above, the contour structure of the workpiece W can be extracted based on the workpiece CAD model. Note that the method for extracting the contour structure is not limited to the example above.

[0081] Figure 5 shows an example of projection of a measurement support image according to this embodiment. As shown in the upper left of Figure 5, when the installation position and orientation of the workpiece W match the workpiece installation position / orientation information D30 (including after offset (S30)), as shown in the lower left of the same figure, the line segments showing the contour structure of the workpiece W in the measurement support image AS1 match the contour of the actual (projection target) workpiece W.

[0082] On the other hand, as shown in the upper right of Figure 5, if the installation position and orientation of the workpiece W do not match the workpiece installation position / orientation information D30 (including after offset (S30)), the line segments showing the contour structure of the workpiece W in the measurement support image AS2 will be shifted from the actual (projected) contour position of the workpiece W, as shown in the lower right of the same figure.

[0083] According to this embodiment, the positional displacement of the workpiece W can be easily visualized by projecting a measurement support image, and the reproducibility of the installation position and orientation of the workpiece W can be confirmed.

[0084] [Second Embodiment] In the second embodiment, an image including the shape of the workpiece W, specifically the surface and datums such as holes formed on the surface (see Japanese Industrial Standard JIS Z 8114: 1999), is projected as a measurement support image.

[0085] Figure 6 is a data flow diagram showing the projection method according to the second embodiment. In the following description, parts common to the first embodiment will be omitted from the explanation.

[0086] First, the control device 100 acquires datum information D12 and installation position / orientation information D30 of the workpiece W.

[0087] Datum information D12 includes information about the shape that will become the datum of the workpiece W. Here, the shape that will become the datum is, for example, information that indicates the shape and dimensions of a circle, cylinder or its contour, or a plane or curved surface in the workpiece CAD model D10.

[0088] In this embodiment, the datum information D12 is moved and rotated based on the workpiece installation position and orientation information D30 acquired during the first measurement (S10). Then, the datum information D12 is rendered (S14) to generate a measurement support image with brightness and color corresponding to the shape of the workpiece W that will become the datum. This measurement support image is then projected from the projection device 50 onto the workpiece W on the surface plate 18 (S16).

[0089] Figures 7 and 8 show examples of projection of measurement support images according to this embodiment. Figure 7 shows an example of a measurement support image used for measuring the surface constituting the workpiece W, and Figure 8 shows an example of a measurement support image used for measuring structures (e.g., holes) on the surface of the workpiece W.

[0090] In the example shown in Figure 7, an image with substantially uniform brightness and color (for example, green) is projected onto the plane SF1 of the workpiece W that is being probed. If the surface being probed is not flat, the brightness or color of the measurement support image may be changed according to its shape (degree of unevenness), etc.

[0091] Furthermore, in the example shown in Figure 7, the images representing the points P1 to P3 to be probed (e.g., dots or circles) are projected in a different color (e.g., blue) than the plane SF1. Alternatively, images representing points that have already been probed may be projected in a different color.

[0092] As shown in the example in Figure 7, the operator can easily visually identify the plane SF1 and points P1 to P3 that are to be probed.

[0093] In the example shown in Figure 8, images H1 and H2, which show the contours of holes formed on the surface of the workpiece W, are projected. Images H1 and H2 may have substantially uniform brightness and color (e.g., green), or their brightness or color may vary depending on their size or the order of probing.

[0094] Furthermore, in the example shown in Figure 8, images A1 to A2, which indicate the probing target, are projected in a different color (for example, blue) than image H1, along image H1, which shows the outline of the hole. Images A1 to A2 are in the shape of arrows indicating the direction of probing (opposite the direction of travel of the probe 22), but are not limited to this. Images A1 to A2 may be any shape that can indicate direction, for example, and may include text information, etc. Also, images A1 to A2 may have substantially uniform brightness and color (for example, red), or their brightness or color may be varied according to the order of probing, etc.

[0095] As shown in the example in Figure 8, the worker can easily visually identify the holes to be probed (H1 to H2) and their probing angles.

[0096] According to this embodiment, the operator can easily visually identify the surface or area to be probed using the measurement support image. This reduces the risk of the operator misidentifying the probing location.

[0097] Furthermore, the measurement support image can be used to project areas that have already been probed using a different color (e.g., red) or shape from images P1-P3, SF1, A1-A2, and H1, making them easily identifiable. This makes it easier for operators to avoid probing the same or nearby areas that have already been probed. By making probed areas easily visible in this way, the risk of deterioration in the accuracy of least-squares approximation for planes or circles can be reduced.

[0098] In this embodiment as well, similar to the first embodiment, an offset value may be input and the measurement support image offset may be performed (S30 to S10 in Figure 3).

[0099] 1...3D measuring machine, 10...measuring device, 12...head, 14...beam, 16...column, 18...surface plate, 18A...surface plate, 20...base, 22...probe, 24...stylus, 26...measuring element, 50...projection device, 52...light source, 54...projection optical system, 100...control device, 102...processing unit, 104...memory, 106...controller, 110...operating unit, 112...display unit

Claims

1. A projection device comprising: a processing unit that generates a measurement support image corresponding to the contour or shape of a workpiece based on the position and orientation of the workpiece installed in the measuring device; and a projection unit that projects the measurement support image onto the workpiece.

2. The projection apparatus according to claim 1, wherein the processing unit generates the measurement support image using relative position information between the measuring device and the projection unit.

3. The projection apparatus according to claim 1, wherein the processing unit generates the measurement support image that distinguishes the area to be probed or the area that has been probed from other areas.

4. The projection apparatus according to claim 1, wherein the processing unit generates a measurement support image indicating the contour structure of the workpiece.

5. The projection apparatus according to claim 1, wherein the processing unit generates a measurement support image indicating at least one of the surface of the workpiece to be measured, a point on the surface, and the contour of a hole formed in the workpiece.

6. The projection apparatus according to claim 5, wherein the processing unit generates a measurement support image indicating a probing angle for a hole formed in the workpiece.

7. The projection device according to claim 1, comprising an operating unit for receiving input of an offset value for the installation position and orientation of the workpiece, wherein the processing unit adjusts the amount of movement and rotation of the measurement support image using the offset value.

8. A projection method comprising the steps of: generating a measurement support image corresponding to the contour or shape of a workpiece based on the position and orientation of the workpiece installed on the measuring device; and projecting the measurement support image onto the workpiece.

Images