Calibration method for 3D shape measuring equipment, 3D shape measuring device and automatic processing device

Abstract

To provide a calibration method for three-dimensional shape measuring equipment, three-dimensional shape measuring device and automatic processing device that can accurately calculate the installation errors around multiple installation direction axes of the three-dimensional measuring equipment using a simple device configuration.SOLUTION: The calibration method for a three-dimensional shape measuring device is a calibration method for a three-dimensional shape measuring device that calibrates installation errors of a three-dimensional shape measuring device 5 for measuring a three-dimensional shape of an object S to be measured. The calibration method includes calculation steps (steps S14, S4, and S115) in which the calibration device 10 calculates each of the installation errors of the three-dimensional shape measuring device 5 about a plurality of installation direction axes (first horizontal axis (xs axis), second horizontal axis (ys axis), and vertical axis (zs axis)) using different calculation methods for each of the installation direction axes (the first horizontal axis (xs axis), the second horizontal axis (ys axis), and the vertical axis (zs axis)).SELECTED DRAWING: Figure 9

Description

[Technical Field]

[0001] The present invention relates to a calibration method for a three-dimensional shape measuring device, a three-dimensional shape measuring device, and an automatic processing device. [Background technology]

[0002] The plate refining process in steelworks is a process of refining metal (steel, aluminum, titanium) plates as objects to be measured, and in this plate refining process, the plates are cut by thermal cutting such as gas cutting, laser cutting, plasma cutting, etc. After cutting the plates, the longitudinal, width, and diagonal dimensions and flatness of the cut plates are measured. Here, conventional measurements of the dimensions and flatness of thick plates after cutting are still often done manually using tools such as tape measures and height gauges. This manual measurement of thick plates after cutting requires heavy physical labor, and there is a risk of falls due to poor work footing, and the risk of collisions and crushing due to interference with the cutting equipment when working inside the line. Furthermore, because measurements are done manually, there are concerns that measurement accuracy may be subject to individual differences and human error, and there are also issues with not being able to take many measurement points.

[0003] In order to solve these problems, a three-dimensional measuring device for an object using a light-section method has been proposed in the past, as shown in Patent Document 1, for example, to automatically measure the dimensions and flatness of a thick plate using a three-dimensional measuring device. The three-dimensional measuring device disclosed in Patent Document 1 includes a table on which an object is placed, actuators provided on both ends of the table, multiple slit light sources installed to illuminate the object from multiple directions at right angles, and multiple cameras that capture the light reflected from the object.The three-dimensional measuring device also includes a portal frame that supports multiple pairs of slit light sources and cameras in predetermined positions and has a movement mechanism at its end that moves along the actuators.The three-dimensional measuring device also includes multiple image processing devices that process image data from each camera, and a computer that processes the three-dimensional measurement data from each image processing device and controls the control unit.

[0004] Furthermore, as a calibration device for an optical head unit in a three-dimensional shape measurement device using the light section method, for example, the device shown in Patent Document 2 has been known. The calibration device for a three-dimensional shape measurement device disclosed in Patent Document 2 includes a detachable optical head equipped with a slit light source and a camera, and a guide unit that allows the detached optical head to move in a predetermined orientation. The calibration device also includes multiple rows of calibration blocks with known dimensions arranged in a descending staircase pattern along the movement direction of the optical head. The optical head is then moved along the guide unit of the calibration device, and each calibration block is photographed with the camera while irradiated with slit light from the slit light source. The camera then extracts the slit light emission lines from the images. The coordinates of the extracted slit light emission lines on the image plane are then calculated, and the coordinates of these emission lines in real space are calculated from the corresponding positions of the calibration blocks and the camera. These coordinates are then stored as a mapping table. When measuring a measurement object using the light-section method, the coordinates on the image plane of the slit light emission lines in the image captured by the camera are calculated. The coordinates of the slit light emission lines in real space in the image captured by the camera are then calculated from the correspondence between the coordinates of each emission line on the image plane and the coordinates in real space stored in the mapping table, and the captured image is corrected. [Prior art documents] [Patent documents]

[0005] [Patent Document 1] Patent No. 3375439 [Patent Document 2] Japanese Patent Application Laid-Open No. 2007-33039 Summary of the Invention [Problem to be solved by the invention]

[0006] However, in the conventional three-dimensional measuring device shown in Patent Document 1, when the slit light source and camera are attached to the portal frame, attachment errors may occur in the direction of travel of the portal frame (x direction), the horizontal direction (y direction) perpendicular to this direction of travel, and the vertical direction (z direction) perpendicular to these directions of travel and horizontal direction. If these attachment errors occur in the slit light source and camera, errors may occur in the image data captured by the camera. On the other hand, the calibration device for the optical head part in the three-dimensional shape measurement device using the light-section method shown in Patent Document 2 can calibrate the installation errors of the slit light source and the camera relative to the optical head in three axes (x-axis, y-axis, and z-axis directions).

[0007] However, in the calibration device for the three-dimensional shape measurement device using the light-section method shown in Patent Document 2, the installation errors for the slit light source and the camera optical head in all three axial directions (x-axis, y-axis, and z-axis) are calculated at once. This causes problems such as a complex configuration of the calibration device and not being able to calculate the installation errors in each of the three axial directions with very high accuracy. Therefore, the present invention has been made to solve the problems of the conventional art, and its object is to provide a calibration method for a three-dimensional shape measuring device, a three-dimensional shape measuring device, and an automatic machining device that can accurately calculate mounting errors around multiple mounting direction axes of a three-dimensional measuring device using a simple device configuration. [Means for solving the problem]

[0008] In order to solve the above problem, one embodiment of the present invention provides a method for calibrating a three-dimensional shape measuring device that calibrates the installation error of a three-dimensional shape measuring device that measures the three-dimensional shape of an object to be measured, and includes a calculation step in which a calibration device calculates installation errors around multiple installation direction axes of the three-dimensional shape measuring device using different calculation methods for each of the installation direction axes. Furthermore, a three-dimensional shape measuring device according to another aspect of the present invention is characterized in that it comprises a three-dimensional shape measuring device that measures the three-dimensional shape of an object to be measured, and a calibration device that calculates installation errors around multiple installation direction axes of the three-dimensional shape measuring device using different calculation methods for each of the installation direction axes.

[0009] Another aspect of the present invention provides an automatic processing device that includes a three-dimensional shape measuring device that measures the three-dimensional shape of a workpiece, a three-dimensional shape measuring device that includes a calibration device that calculates installation errors around multiple installation direction axes of the three-dimensional shape measuring device using different calculation methods for each of the installation direction axes, and a processing device that processes the workpiece, wherein the three-dimensional shape measuring device measures the three-dimensional shape of the workpiece at least either before or after processing by the processing device. [Effects of the Invention]

[0010] According to the calibration method for a three-dimensional shape measuring device, the three-dimensional shape measuring device, and the automatic processing device of the present invention, it is possible to accurately calculate the mounting errors around multiple mounting direction axes of the three-dimensional measuring device with a simple device configuration. [Brief explanation of the drawings]

[0011] [Figure 1] 1 is a schematic configuration diagram of an automatic cutting device as an automatic processing device according to an embodiment of the present invention. [Figure 2] 2 is a block diagram of a control device in the automatic cutting device shown in FIG. 1. FIG. [Figure 3] 1A and 1B are diagrams illustrating the distance sensor mounting angle adjustment mechanism in the automatic cutting device shown in FIG. 1, where FIG. 1A is a diagram illustrating the distance sensor mounting angle adjustment around two horizontal axes (ys axes), FIG. 1B is a diagram illustrating the distance sensor mounting angle adjustment around a vertical axis (zs axis), and FIG. 1C is a diagram illustrating the distance sensor mounting angle adjustment around a single horizontal axis (xs axis). [Figure 4]This explains a method for measuring the three-dimensional shape of a thick plate using an automatic cutting device, where (a) is a plan view of the thick plate placed on the base of the automatic cutting device, and (b) is a plan view explaining how the distance sensor moves in a zigzag pattern as shown by arrow A in a plan view from the state shown in (a) to measure the three-dimensional shape of the thick plate. [Figure 5] This explains how to calculate the mounting error of the mounting angle of the distance sensor around two horizontal axes (ys-axes). (a) is an explanatory diagram of the state in which the distance sensor is irradiating laser light onto the top surface of the base plate as a calibration member, and (b) is an explanatory diagram of the state in which the distance sensor attached to the tool is irradiating laser light onto the top surface of the base plate as a calibration member with a mounting error Δθy around two horizontal axes (ys-axes). [Figure 6] This explains a method for calculating the mounting error of the mounting angle of a distance sensor around a single horizontal axis (xs axis). (a) is an explanatory diagram of the state in which the distance sensor is irradiating laser light onto two horizontal surfaces of a calibration block, which serves as a calibration member placed on a surface plate. (b) is an explanatory diagram of the state in which the distance sensor attached to a tool is irradiating laser light onto two horizontal surfaces of the calibration block when there is an installation error Δθx around the single horizontal axis (xs axis). (c) is a diagram showing the geometric relationship between the known height difference h between the two horizontal surfaces of the calibration block and the height difference herr between the two horizontal surfaces of the calibration block when there is an installation error Δθx around the single horizontal axis (xs axis). [Figure 7]This explains a method for calculating the mounting error of the mounting angle of a distance sensor around the vertical axis (zs axis), where (a) is an explanatory diagram of the state in which the distance sensor is irradiating laser light onto two horizontal surfaces of a calibration block, which serves as a calibration member placed on a surface plate, (b) is a plan view of the distance sensor attached to the tool with a mounting error Δθz around the vertical axis (zs axis), (c) is an explanatory diagram of the distance sensor attached to the tool measuring the calibration block along two different measurement paths a and b with a mounting error Δθz around the vertical axis (zs axis), and (d) is a diagram for explaining a method for calculating the mounting angle at which the two coordinate transformation values match by superimposing two coordinate transformation values for each of two 3D shape measurement data obtained by measuring the calibration block along two different measurement paths a and b using the method in (c). [Figure 8] 10 is a flowchart illustrating a process for calculating mounting errors around two horizontal axes (ys axes) of a distance sensor using a three-dimensional shape measuring device. [Figure 9] 10 is a flowchart illustrating a process for calculating an installation error around a horizontal axis (xs axis) of a distance sensor using a three-dimensional shape measuring device. [Figure 10] 10 is a flowchart illustrating a process for calculating an installation error around the vertical axis (zs axis) of a distance sensor using a three-dimensional shape measuring device. [Figure 11] FIG. 10 is a plan view for explaining a method for measuring the three-dimensional shape of a thick plate using a modified example of the automatic cutting device. [Figure 12] 10 is a graph for explaining the effect of an embodiment in which the mounting angles of the distance sensor around two horizontal axes (ys axes) are calibrated by the calibration method of the present invention. [Figure 13] This is an explanatory diagram of an example in which the mounting angle of a distance sensor around the vertical axis (zs axis) is calibrated using the calibration method of the present invention, and is a diagram illustrating the state in which the distance sensor is irradiating laser light onto a square as a calibration member placed on a surface plate. [Figure 14]13A and 13B illustrate an example in which the mounting angle of a distance sensor around the vertical axis (zs axis) is calibrated using the calibration method of the present invention, where FIG. 13A is an explanatory diagram showing three-dimensional shape measurement data obtained by measuring with a square along measurement path a shown in FIG. 13, and FIG. 13B is an explanatory diagram showing three-dimensional shape measurement data obtained by measuring with a square along measurement path b shown in FIG. [Figure 15] 13A illustrates an example in which the mounting angle of a distance sensor around the vertical axis (zs axis) is calibrated using the calibration method of the present invention, where (a) is a diagram superimposing coordinate transformation values obtained by coordinate-transforming three-dimensional shape measurement data obtained by measuring a square along measurement path a shown in Figure 13 at the designed mounting angle of the distance sensor θz = 45° and coordinate transformation values obtained by coordinate-transforming three-dimensional shape measurement data obtained by measuring a square along measurement path b shown in Figure 13 at the designed mounting angle of the distance sensor θz = 45°, and (b) is a diagram superimposing coordinate transformation values obtained by coordinate-transforming three-dimensional shape measurement data obtained by measuring a square along measurement path a shown in Figure 13 at the mounting angle of 42.5°, which is changed by Δθz = -2.5° from the designed mounting angle of the distance sensor θz = 45°, and coordinate transformation values obtained by coordinate-transforming three-dimensional shape measurement data obtained by measuring a square along measurement path b shown in Figure 13 at the mounting angle of 42.5°, which is changed by Δθz = -2.5° from the designed mounting angle of the distance sensor θz = 45°. [Figure 16] 1A and 1B are diagrams for explaining methods of measuring the shape of a thick plate in a comparative example in which the shape of the thick plate after cutting is measured before the mounting angle of the distance sensor is calibrated in the automatic cutting device shown in FIG. 1, and in an embodiment in which the shape of the thick plate after cutting is measured after the mounting angle of the distance sensor is calibrated in the automatic cutting device shown in FIG. [Figure 17] 10 is a graph showing measurement results according to a comparative example. [Figure 18] 10 is a graph showing measurement results according to an example. DETAILED DESCRIPTION OF THE INVENTION

[0012] Hereinafter, embodiments of the present invention will be described with reference to the drawings. The embodiments shown below are examples of devices and methods for embodying the technical concept of the present invention, and the technical concept of the present invention is not limited to the materials, shapes, structures, arrangements, etc. of the components in the embodiments described below. Furthermore, the drawings are schematic. Therefore, it should be noted that the relationships and ratios between thicknesses and planar dimensions may differ from the actual ones, and the drawings may also contain portions where the relationships and ratios of dimensions differ from one another. (Overall configuration of the automatic cutting device) FIG. 1 shows a schematic configuration of an automatic cutting device as an automatic processing device according to one embodiment of the present invention.

[0013] The automatic cutting device 1 shown in Figure 1 is a gate-type cutting machine, and is equipped with a gate-type cart 3 that can run on wheels (not shown) on a pair of rails 2 laid out to extend in the x direction (horizontal direction). A tool 4 is mounted on the side of the carriage 3, and is capable of linear movement in the y direction (a horizontal direction perpendicular to the x direction). A distance sensor 5 serving as a three-dimensional measuring device is attached to the tool 4 via an attachment angle adjustment mechanism 7 so as to be capable of linear movement in the z direction (vertical direction). The tool 4 is also provided with a cutting torch 6 serving as a processing device for cutting a thick plate S placed on a base 1a (see FIG. 4(a)) by thermal cutting such as gas cutting, laser cutting, or plasma cutting. The cutting torch 6 is attached to the tool 4 so as to be capable of linear movement in the z direction (vertical direction). Both the distance sensor 5 and the cutting torch 6 are attached to the tool 4 so as to be capable of linear movement, but they do not need to move synchronously, and each can be independently moved linearly in the z direction.

[0014] The distance sensor 5, which serves as a three-dimensional shape measuring device, is a non-contact distance sensor that uses a light-section method to measure the distance to the object (the thick plate S, the surface plate 13, and the calibration block 14, which will be described later) by irradiating a line of laser light onto the object to be measured. As shown in FIGS. 3 to 7 , the distance sensor 5 measures the two-dimensional shape of the object by irradiating a laser light 5c onto the object, capturing an image of the projected laser light 5c with a camera (not shown), and calculating the projection position of the laser light 5c on the image. The distance sensor 5 is then moved in the x and y directions by the carriage 3 and the tool 4, and the three-dimensional shape of the object is measured by sequentially calculating the position coordinates of the tool 4 and the measurement data of the two-dimensional shape measured by the distance sensor 5. In other words, the distance sensor 5 measures the three-dimensional shape of the object by having the function of moving it in the x and y directions by the carriage 3 and the tool 4. The three-dimensional shape measuring device attached to the carriage 3 is not limited to the distance sensor 5 using the light-section method, and other devices capable of measuring two-dimensional shape measurement data of the object may also be used. Other devices capable of measuring two-dimensional shape measurement data include, for example, sensors that use a TOF (Time of Flight) method as the measurement principle, such as a two-dimensional LiDAR sensor.

[0015] The mounting angle adjustment mechanism 7 adjusts the mounting angle of the distance sensor 5 relative to the tool 4. As shown in Figures 3(a), (b), and (c), the mounting direction of the distance sensor 5 is set horizontally and the line direction of the laser light 5c (optical axis 5b) of the distance sensor 5 (the direction in which the laser light 5c spreads) is set along a single horizontal axis (x s The horizontal direction and the horizontal single axis (x s The direction perpendicular to the horizontal axis (y s Furthermore, the laser beam 5c is set to a direction parallel to the optical axis 5b and horizontally along a single axis (x s axis) and horizontal two axes (y s The direction perpendicular to each of the directions is the vertical axis (z s axial) direction. The mounting angle adjustment mechanism 7 is configured to adjust the horizontal axis (x sSimilarly, the mounting angle adjustment mechanism 7 has a rotation axis 7c (see FIG. 3(c)) that rotates the distance sensor 5 around the horizontal two axes (y 1 , y 2 , y 3 ) as mounting direction axes with respect to a coordinate system based on the laser beam 5c of the distance sensor 5. s Similarly, the mounting angle adjustment mechanism 7 is provided with a rotation axis 7b (see FIG. 3(a)) that rotates the distance sensor 5 around a vertical axis (z axis) as a mounting direction axis with respect to a coordinate system based on the laser beam 5c of the distance sensor 5. s The distance sensor 5 is provided with a rotation axis 7a (see FIG. 3(b)) around which the distance sensor 5 is rotated.

[0016] That is, as shown in FIG. 3(a), the mounting angle adjustment mechanism 7 is configured to rotate the rotation axis 7b so that the rotation axis 7b is perpendicular to the optical axis 5b of the distance sensor 5 along two horizontal axes (y s As shown in FIG. 3(b), the mounting angle adjustment mechanism 7 can rotate the distance sensor 5 around a vertical axis (z axis) that is parallel to the optical axis 5b of the distance sensor 5 by using the rotation axis 7a. s 3(c), the mounting angle adjustment mechanism 7 can rotate the distance sensor 5 around a horizontal axis (x axis) that is parallel to the line direction (measurement width direction) of the laser light 5c of the distance sensor 5 by using the rotation axis 7c. s It is possible to rotate the distance sensor 5 around the rotation axes 7a to 7c. In this way, by making the mounting angle of the distance sensor 5 variable using the rotation axes 7a to 7c, it is also possible to correct the actual mounting angle of the distance sensor 5 when calculating the mounting errors Δθx, Δθy, and Δθz of the distance sensor 5, which will be described later.

[0017] The automatic cutting device 1 also includes a control device 8. As shown in Figures 1 and 2, the control device 8 includes a control unit 9, a calibration device 10, and an output unit 11. The control device 8 is a computer system with a processing function, and executes the functions of the control unit 9, the calibration device 10, and the output unit 11 according to instructions from a computer program installed in a storage device (not shown). Here, the control unit 9 controls the operations of each member of the automatic cutting device 1 such as the carriage 3, the tool 4, the distance sensor 5, and the cutting torch 6. Furthermore, the calibration device 10 calculates the installation error of each of the three installation direction axes of the distance sensor 5 as a three-dimensional shape measuring device. Specifically, the calibration device 10 calculates the installation error of each of the three installation direction axes of the distance sensor 5 as a three-dimensional shape measuring device. s axis), two horizontal axes (y s axis), and vertical axis (z s axis), the horizontal axis (x s axis), two horizontal axes (y s axis), and vertical axis (z s When calculating each of these installation errors Δθx, Δθy, Δθz, the horizontal axis (x s axis), two horizontal axes (y s axis), and vertical axis (z s A different calculation method is used for each axis.

[0018] As shown in Fig. 2, the calibration device 10 includes an installation error calculation unit 10a and an installation error output unit 10b. The installation error calculation unit 10a calculates the installation error along a single horizontal axis (x s axis), two horizontal axes (y s axis), and vertical axis (z s A horizontal axis (x axis) is calculated using a different calculation method. s axis), two horizontal axes (y s axis), and vertical axis (z s The installation error output unit 10b calculates the installation errors Δθx, Δθy, and Δθz around the horizontal axis (x s axis), two horizontal axes (y s axis), and vertical axis (z s The mounting errors Δθx, Δθy, and Δθz around each axis are output, and this information is displayed on a display device such as a monitor. The output unit 11 outputs the coordinate transformation value Σ obtained by the coordinate transformation performed by the coordinate transformation unit 5a of the distance sensor 5. R (the position of the workpiece in the xyz (movement) coordinate system in which the tool 4 is located) is acquired, and its coordinate transformation value Σ R and outputs the coordinate transformation value Σ as the 3D shape measurement data of the object to be measured. R is displayed on a display device such as a monitor.

[0019] The distance sensor 5 as the three-dimensional shape measuring device and the calibration device 10 constitute a three-dimensional shape measuring device 12. 1, the distance sensor 5 is provided with a coordinate conversion unit 5a. The coordinate conversion unit 5a converts the measurement values (three-dimensional shape measurement data) in the sensor coordinate system measured by the distance sensor 5 into coordinate conversion values in the moving coordinate system of the tool 4 (the position of the object to be measured in the xyz (moving) coordinate system in which the tool 4 is placed) using the following equation (1). The coordinate conversion unit 5a is a computer with an arithmetic processing function, and executes the coordinate conversion function in accordance with the instructions of a computer program installed in a storage device (not shown).

[0020] Σ R =M s +R x ·R y ·R z ·Σ s …(1) Here, Σ R is the coordinate transformation value of the moving coordinate system of the tool 4 (the position of the workpiece in the xyz coordinate system in which the tool 4 is placed). M s is the position coordinate of tool 4. R x is the horizontal axis of the sensor coordinate system (x s coordinate transformation matrix around the axis, R y are the horizontal axes (y s coordinate transformation matrix around the axis, R z is the vertical axis of the sensor coordinate system (z s is the coordinate transformation matrix around the Σ s is the measurement value in the sensor coordinate system (3D shape measurement data). And R x , R y , R z are expressed by the following equations (2) to (4), respectively.

[0021]

number

[0022] First, the thick plate S is placed on a base 1a between a pair of rails 2 of the automatic cutting device 1, as shown in FIG. 4(a). Then, as shown in Figure 4(b), the control unit 9 controls the carriage 3 and the tool 4 to move the distance sensor 5 in a zigzag pattern in a planar view relative to the thick plate S to be measured, as indicated by the arrow A, and the distance sensor 5 measures the three-dimensional shape of the thick plate S. Then, the measurement value (three-dimensional shape measurement data) Σ in the sensor coordinate system measured by the distance sensor 5 s are converted into coordinate transformation values in the moving coordinate system of the tool 4 (the position of the workpiece in the xyz (moving) coordinate system in which the tool 4 is placed) in the coordinate conversion unit 5a using the above-mentioned equation (1).

[0023] In addition, the distance sensor 5 is designed to have a single horizontal axis (x s axis), the mounting angle θx around the horizontal two axes (y s The mounting angle θy around the vertical axis (z s The mounting angle θz around the axis is input in advance by an operator to the coordinate conversion unit 5a via an input device (not shown). In addition, the position coordinates M of the tool 4 in the x, y and z directions sThe amount of rotation of the actuator in each direction is obtained by a rotary encoder, and the obtained information is input to the coordinate conversion unit 5a. Then, the coordinate transformation value of the moving coordinate system of the tool 4 transformed by the coordinate transformation unit 5a (the position of the thick plate S in the xyz coordinate system where the tool 4 is arranged) Σ R is sent to the output unit 11, which outputs the coordinate transformation value Σ R and outputs the coordinate transformation value Σ as the 3D shape measurement data of the object to be measured. R is displayed on a display device such as a monitor. (Method for calibrating distance sensor installation errors) When the mounting angle of the distance sensor 5 relative to the tool 4 is different from the designed mounting angles θx, θy, θz, the coordinate transformation value of the moving coordinate system of the tool 4 (the position of the workpiece (thick plate S) in the xyz coordinate system where the tool 4 is located) Σ R Therefore, when the horizontal axis (x s The mounting error Δθx of the mounting angle around the horizontal two axes (y s The mounting error Δθy of the mounting angle around the vertical axis (z s It is necessary to calculate the mounting error Δθz of the mounting angle around the axis and calibrate that error.

[0024] In this embodiment, the calibration device 10 detects the horizontal axis (x s axis), two horizontal axes (y s axis), and vertical axis (z s axis), the horizontal axis (x s axis), two horizontal axes (y s axis), and vertical axis (z s When calculating each of these installation errors Δθx, Δθy, Δθz, the horizontal axis (x s axis), two horizontal axes (y s axis), and vertical axis (z s A different calculation method is used for each axis. A. The horizontal two axes (y s Calculation method for mounting error Δθy around the axis The two horizontal axes (y s A method for calculating the mounting error Δθy around two horizontal axes (y s This explains how to calculate the installation error of a distance sensor around two horizontal axes (y axis). (a) is an explanatory diagram of the state in which the distance sensor is irradiating laser light onto the top surface of a surface plate used as a calibration member, and (b) is an explanatory diagram of the state in which the distance sensor is irradiated with laser light onto the top surface of a surface plate used as a calibration member, and (c) is an explanatory diagram of the state in which the distance sensor is irradiated with laser light onto the top surface of a surface plate used as a calibration member, and (d) is an explanatory diagram of the state in which the distance sensor is irradiated with laser light onto the top surface of a surface plate used as a calibration member, and (e) is an explanatory diagram of the state in which the distance sensor is irradiated with laser light onto the top surface of a surface plate used as a calibration member, and (f ... s 8 is an explanatory diagram of a state in which a distance sensor attached to a tool irradiates laser light onto the top surface of a surface plate as a calibration member in the presence of an installation error Δθy around two horizontal axes (y s 10 is a flowchart illustrating a process for calculating an installation error around an axis.

[0025] First, in step S1 shown in Fig. 8, an operator places a surface plate 13 serving as a calibration member having a leveled horizontal surface 13a (see Figs. 5(a) and (b)) on the base 1a of the automatic cutting device 1. It is desirable that the surface plate 13 be portable and have an adjuster that can adjust the inclination of the surface plate 13. Next, in step S2, the operator sets the control unit 9, the calibration device 10, and the coordinate conversion unit 5a of the distance sensor 5 to the horizontal two axes (y s A command to calculate the mounting error Δθy around the axis is input, and the three-dimensional shape measuring device 12 is started. Next, in step S3, the distance sensor 5 as a three-dimensional shape measuring device measures the horizontal surface 13a of the surface plate 13 (surface plate measuring step). At this time, the control unit 9 controls the carriage 3 and the tool 4, and controls the position of the distance sensor 5.

[0026] Next, in step S4, the installation error calculation unit 10a of the calibration device 10 acquires shape data of the horizontal surface 13a of the surface plate 13 having the leveled horizontal surface 13a measured by the distance sensor 5 in step S3. Then, the installation error calculation unit 10a approximates the acquired shape data of the horizontal surface 13a to a linear function to calculate the inclination of the horizontal surface 13a, thereby obtaining the two horizontal axes (y s The mounting error Δθy around the axis is calculated (calculation step). Here, if an error occurs in the mounting angle of the distance sensor 5, the shape data of the horizontal surface 13a of the surface plate 13 measured by the distance sensor 5 is output with an inclination of the mounting error Δθy of the distance sensor 5, as shown in FIG. 5(b). The coordinate conversion unit 5a of the distance sensor 5 does not perform coordinate conversion on the shape data of the horizontal surface 13a measured by the distance sensor 5, and sends the shape data to the mounting error calculation unit 10a of the calibration device 10. The mounting error calculation unit 10a acquires the shape data of the horizontal surface 13a of the surface plate 13, approximates the acquired shape data of the horizontal surface 13a to a linear function, and calculates the inclination of the horizontal surface 13a, thereby obtaining the shape data of the horizontal two axes (y s Calculate the mounting error Δθy around the axis.

[0027] Next, in step S5, the installation error output unit 10b of the calibration device 10 outputs the horizontal two-axis (y s The mounting error Δθy around the axis is output, and the information is displayed on a display device such as a monitor (mounting error output process). B. The horizontal axis (x s Calculation method for mounting error Δθx around the axis The horizontal axis (x s A method for calculating the mounting error Δθx around a horizontal axis (x axis) will be described with reference to FIGS. 6 and 9. s This explains how to calculate the mounting error of a distance sensor around a horizontal axis (x axis). (a) is an explanatory diagram of the state in which the distance sensor is irradiating laser light onto two horizontal surfaces of a calibration block placed on a surface plate as a calibration member, and (b) is an explanatory diagram of the state in which the distance sensor is irradiating laser light onto two horizontal surfaces of a calibration block placed on a surface plate as a calibration member s (c) shows the known height difference h between the two horizontal surfaces of the calibration block and the horizontal axis (x s9 is a diagram showing the geometric relationship between the difference in height herr of the two horizontal planes of the calibration block when a distance sensor attached to a tool irradiates laser light onto the two horizontal planes of the calibration block in the presence of an installation error Δθx around the horizontal axis (x axis). s 10 is a flowchart illustrating a process for calculating an installation error around an axis.

[0028] First, in step S11 shown in FIG. 9, an operator places a calibration block 14, which serves as a calibration member, on a surface plate 13 and has two horizontal surfaces 14a, 14b (see FIGS. 6(a), (b), and (c)) that are parallel to each other but have different heights and whose difference in leveled height h is known. Next, in step S12, the operator sets the control unit 9, the calibration device 10, and the coordinate conversion unit 5a of the distance sensor 5 to a horizontal axis (x s A command to calculate the mounting error Δθx around the axis is input, and the three-dimensional shape measuring device 12 is started. Next, in step S13, the distance sensor 5 serving as a three-dimensional shape measuring device measures the height difference herr (see FIG. 6(c)) between the two horizontal surfaces 14a, 14b of the calibration block 14 (height difference measurement step). At this time, the control unit 9 controls the carriage 3 and the tool 4 to control the position of the distance sensor 5. Note that in the example shown in FIGS. 6(a), (b), and (c), the two horizontal surfaces 14a, 14b of the upper and middle stages of the two-stage calibration block 14 are the measurement targets, but the two horizontal surfaces, the upper stage horizontal surface 14a of the one-stage calibration block 14 and the horizontal surface of the surface plate 13, may also be the measurement targets.

[0029] Next, in step S14, the installation error calculation unit 10a of the calibration device 10 acquires data on the height difference herr between the two horizontal surfaces 14a, 14b of the calibration block 14, which has two horizontal surfaces 14a, 14b with a known leveled height difference h, measured by the distance sensor 5 in step S13. Then, the installation error calculation unit 10a calculates the height difference herr based on the known height difference h and the acquired height difference herr data. distanceThe horizontal axis (x s The mounting error Δθx around the axis is calculated (calculation step). child Therefore, the coordinate conversion unit 5a of the distance sensor 5 sends the data of the height difference herr measured by the distance sensor 5 to the installation error calculation unit 10a of the calibration device 10 without performing coordinate conversion on the data of the height difference herr.

[0030] Next, in step S15, the installation error output unit 10b of the calibration device 10 outputs the horizontal axis (x s The mounting error Δθx around the axis is output, and the information is displayed on a display device such as a monitor (mounting error output process). C. The vertical axis (z s Calculation method for mounting error Δθz around the axis The vertical axis (z s A method for calculating the mounting error Δθz around the vertical axis (z axis) will be described with reference to FIGS. 7 and 10. s This explains how to calculate the installation error of a distance sensor around the vertical axis (z axis). (a) is an explanatory diagram of the state in which the distance sensor is irradiating laser light onto two horizontal surfaces of a calibration block placed on a surface plate as a calibration member, and (b) is an explanatory diagram of the state in which the distance sensor is irradiating laser light onto two horizontal surfaces of a calibration block placed on a surface plate as a calibration member s (c) is a plan view of the distance sensor attached to the tool with an installation error Δθz around the vertical axis (z s FIG. 10 is an explanatory diagram of measuring a calibration block along measurement paths a and b in two different directions by a distance sensor attached to a tool in the presence of an installation error Δθz around the vertical axis (z axis), and (d) is a diagram for explaining a method for calculating an installation angle at which the coordinate transformation values of the two moving coordinate systems coincide by superimposing the coordinate transformation values of the moving coordinate systems obtained by coordinate transformation for each of two three-dimensional shape measurement data obtained by measuring the calibration block along measurement paths a and b in two different directions using the method in (c). s 10 is a flowchart illustrating a process for calculating an installation error around an axis.

[0031] 10, the operator places a calibration block 14, which has horizontal surfaces 14a and 14b and is square in plan view as a calibration member, on the surface plate 13, as shown in FIG. 7(a). The shape of the calibration block 14 is not limited to a three-dimensional shape having horizontal surfaces 14a and 14b and is square in plan view, but may also be a cube, a cylinder, a rectangular parallelepiped, or the like. Next, in step S112, the operator sets the vertical axis (z s The operator inputs a command to calculate the mounting error Δθz around the axis (axis) and starts the three-dimensional shape measuring device 12. The operator also inputs information on the mounting angles θx, θy, θz of the designed distance sensor 5 and the minute angle dθz in the range of the mounting angle θz±θ of the designed distance sensor 5 to be coordinate converted to the coordinate conversion unit 5a of the distance sensor 5.

[0032] Next, in step S113, the distance sensor 5 as a three-dimensional shape measuring device measures the calibration block 14 from measurement paths a and b in two different, perpendicular directions, as shown in Fig. 7(c) (calibration block different direction measurement step). At this time, the control unit 9 controls the carriage 3 and tool 4 to control the position of the distance sensor 5. Note that the measurement directions of the measurement paths a and b are perpendicular to each other, but this is not necessarily the case. Next, in step S114, the coordinate conversion unit 5a of the distance sensor 5 performs coordinate conversion using equation (1) for each of the two pieces of three-dimensional shape measurement data measured in step S113 (two pieces of data measured along measurement path a and measurement path b). During this coordinate conversion, the coordinate conversion is performed using equation (1) for each small angle dθz within the range of ±θ from the design mounting angle θz. Then, the coordinate conversion values Σ of the two moving coordinate systems are calculated. r,a , Σ r,b(coordinate transformation step). At this time, the information on the mounting angles θx, θy, θz of the designed distance sensor 5 and the minute angle dθz in the range of the mounting angle θz±θ of the designed distance sensor 5 to be coordinate transformed, which are introduced into the equation (1), are input to the coordinate transformation unit 5a in step S112. s The amount of rotation of the actuator in each of the x-direction, y-direction, and z-direction is obtained by a rotary encoder, and the obtained information is input to the coordinate conversion unit 5a.

[0033] The two pieces of three-dimensional shape measurement data measured in step S113 (two pieces of data measured along measurement path a and measurement path b) are each subjected to coordinate conversion using equation (1) at the design mounting angle θz, and the coordinate conversion value Σ of the moving coordinate system is obtained as shown in FIG. 7(d). r,a , Σ r,b If there is an error in the mounting angle (θz) of the distance sensor 5, the shape of the measured calibration block 14 is calculated as distorted, as shown in figures 15a and 15b in Figure 7(d). The distortion of the shape differs depending on the measurement path. Therefore, in this embodiment, in step S114, the coordinate conversion unit 5a of the distance sensor 5 converts the coordinates of each of the two three-dimensional shape measurement data measured in step S113 for each minute angle dθz in the range of ±θ from the designed mounting angle θz using equation (1), to obtain coordinate conversion values Σ of the two moving coordinate systems. r,a , Σ r,b Then, in the next step S115, the calibration device 10 calculates the coordinate transformation value Σ r,a , Σ r,b The mounting angle at which the distance sensor 5's vertical axis (z s The mounting error Δθz around the axis is calculated.

[0034] Next, in step S115, the installation error calculation unit 10a of the calibration device 10 calculates the coordinate transformation values Σ of the two moving coordinate systems that were transformed by the coordinate transformation unit 5a of the distance sensor 5 in step S114. r,a (Figure 7(d) shown by reference numeral 15a), Σr,b (Figure indicated by reference numeral 15b in FIG. 7(d)). Then, the installation error calculation unit 10a calculates the coordinate transformation values Σ r,a , Σ r,b The coordinate transformation value Σ of the two moving coordinate systems is obtained by superimposing r,a , Σ r,b The mounting angle is calculated so that the vertical axis (z s The mounting error Δθz around the axis is calculated (calculation step). In FIG. 7(d), the coordinate transformation value Σ r,a , Σ r,b are respectively the figures indicated by the reference numerals 16a and 16b.

[0035] Here, the coordinate transformation value Σ of the two moving coordinate systems r,a , Σ r,b is the coordinate transformation value of the moving coordinate system Σ r,a The edge of the 3D point cloud data and the coordinate transformation value Σ of the moving coordinate system r,b This means that the edge portions of the three-dimensional point cloud data overlap. Here, "overlapping" means that the distance between the edge portions is 1.0 mm or less. For example, if the designed mounting angle θz of the distance sensor 5 is 45° and coordinate transformation is performed in increments of 0.1° within a range of ±3°, the coordinate transformation values Σ of the two moving coordinate systems are 42.0°, 42.1°, 42.2°, . . . , 47.9°, and 48.0° in sequence. r,a , Σ r,b Then, the coordinate transformation value Σ of the two moving coordinate systems is calculated. r,a , Σ r,b Stacked Σ r,a , Σ r,b The angle when the edge portions of the three-dimensional point cloud data overlap is the mounting angle θz±mounting error Δθz.

[0036] Next, in step S116, the installation error output unit 10b of the calibration device 10 outputs the vertical axis (z s The mounting error Δθz around the axis is output, and the information is displayed on a display device such as a monitor (mounting error output process). D. Calibration of the mounting angle of distance sensor 5 In this embodiment, after the installation errors Δθx, Δθy, and Δθz are calculated by the above-described methods A to C, the installation angle of the distance sensor 5 is calibrated based on the calculated installation errors Δθx, Δθy, and Δθz.

[0037] As a method for calibrating the mounting angle of the distance sensor 5, for example, there is a method of directly correcting the mounting angle of the distance sensor 5 by the calculated mounting errors Δθx, Δθy, Δθz. Also, using the above-mentioned equation (1), the measurement value Σ in the sensor coordinate system is s The coordinate transformation value Σ of the moving coordinate system of tool 4 R (the position of the workpiece in the xyz coordinate system in which the tool 4 is located) x , R y , R z There is a way to correct this. In the former case of directly correcting the mounting angle of the distance sensor 5, the mounting angle of the distance sensor 5 is corrected by the calculated mounting errors Δθx, Δθy, Δθz, and then the distance sensor 5 is used to measure the three-dimensional shape of the object to be measured.

[0038] On the other hand, the latter coordinate transformation sequence R x , R y , R z When correcting the distance, the three-dimensional shape of the object to be measured is measured using the distance sensor 5 without correcting the mounting angle of the distance sensor 5. Then, the measurement value Σ in the sensor coordinate system is s When the coordinate conversion unit 5a converts the coordinates, the calculated installation errors Δθx, Δθy, and Δθz are taken into consideration and the coordinate conversion sequence R in the equation (1) is x , R y , R z Specifically, the calculated mounting errors Δθx, Δθy, and Δθz are added to the design mounting angles θx, θy, and θz in equations (2) to (4) to obtain the corrected coordinate transformation matrix R x , R y , R z is calculated using the following equations (6) to (8). Then, the corrected coordinate transformation matrix R x , R y , R z to the measured value in the sensor coordinate system Σ sand add the position coordinate of tool 4 to obtain the coordinate transformation value Σ of the moving coordinate system of tool 4 using equation (1). R (the position of the workpiece in the xyz coordinate system in which the tool 4 is placed) is calculated.

[0039]

number

[0040] Next, the thick plate S before cutting is placed on the base 1a of the automatic cutting device 1, and the three-dimensional shape of the thick plate S is measured using the distance sensor 5. Then, the measurement value Σ in the sensor coordinate system measured by the distance sensor 5 is s The coordinate conversion unit 5a converts the coordinates of the moving coordinate system of the tool 4 into the coordinate conversion value Σ R (the position of the plate S in the xyz coordinate system where the tool 4 is arranged). x , R y , R z If you want to correct the measured value Σ in the sensor coordinate system at this point, s When the coordinate conversion unit 5a converts the coordinates, the calculated installation errors Δθx, Δθy, and Δθz are taken into consideration and the coordinate conversion sequence R in the equation (1) is x , R y , R z Then, these corrected coordinate transformation matrix R x , R y , R z The measured value in the sensor coordinate system Σ s(3D shape measurement data measured by distance sensor 5) and add the position coordinate of tool 4 to obtain the coordinate transformation value Σ of the moving coordinate system of tool 4 using equation (1). R (The position of the thick plate S in the xyz coordinate system in which the tool 4 is placed) is calculated.

[0041] And the coordinate transformation value Σ of the moving coordinate system of tool 4 R The cutting position of the thick plate S is determined from the cutting position (the position of the thick plate S in the xyz coordinate system where the tool 4 is placed), and the automatic cutting device 1 aligns the tool 4 along the cutting position and cuts the thick plate S with the cutting torch 6. This cuts out a thick plate product of the specified product dimensions. Then, the three-dimensional shape of the cut thick plate product is measured again using the distance sensor 5, and the measurement value Σ in the sensor coordinate system measured by the distance sensor 5 is calculated. s The coordinate conversion unit 5a converts the coordinates of the moving coordinate system of the tool 4 into the coordinate conversion value Σ R The coordinate transformation matrix R is used to calibrate the mounting angle of the distance sensor 5. x , R y , R z If you want to correct the measured value Σ in the sensor coordinate system at this point, s When the coordinate conversion unit 5a converts the coordinates, the calculated installation errors Δθx, Δθy, and Δθz are taken into consideration and the coordinate conversion sequence R in the equation (1) is x , R y , R z Then, these corrected coordinate transformation matrix R x , R y , R z The measured value in the sensor coordinate system Σ s and add the position coordinate of tool 4 to obtain Σ R : Determine the moving coordinate system (the position of the thick plate S in the xyz coordinate system where the tool 4 is placed).

[0042] As described above, according to the method for calibrating a three-dimensional shape measuring device according to this embodiment, the calibration device 10 calibrates the three mounting direction axes (horizontal axis (x saxis), two horizontal axes (y s axis), and vertical axis (z s The calculation process includes a calculation step (step S14, step S4, step S115) for calculating the mounting error around each of the three mounting direction axes (horizontal axis (x s axis), two horizontal axes (y s axis), and vertical axis (z s The installation error around each of the three installation direction axes is calculated using a different calculation method for each axis. This allows the installation error of the distance sensor 5 as a three-dimensional shape measuring device to be calculated using the optimum calculation method corresponding to each installation direction axis, and the three installation direction axes of the distance sensor 5 (horizontal axis (x s axis), two horizontal axes (y s axis), and vertical axis (z s The mounting error around the axis can be calculated with high accuracy.

[0043] Furthermore, since only the mounting error around one axis in the mounting direction is calculated using one calculation method, the device configuration and calculation process for each calculation method can be simplified. Furthermore, according to the method for calibrating a three-dimensional shape measuring device according to the embodiment, the calibration device 10 calibrates the horizontal axis (x s In a calculation step (step S14) of calculating the mounting error around the horizontal axis, the following process is performed. That is, the calibration device 10 acquires data on the height difference herr between the two horizontal surfaces 14a, 14b of the calibration block 14, which serves as a calibration member having two horizontal surfaces 14a, 14b with a known leveled height difference h, measured by the distance sensor 5 (measured in step S13). Then, the calibration device 10 calculates the mounting error Δθx around the horizontal axis of the distance sensor 5 using the above-mentioned equation (5) based on the known height difference h and the acquired height difference herr data (step S14).

[0044] This makes it possible to calculate the mounting error Δθx of the distance sensor 5 around a single horizontal axis with high accuracy using a simple method. Furthermore, according to the method for calibrating a three-dimensional shape measuring device according to this embodiment, the calibration device 10 calibrates the horizontal two axes (y s In a calculation step (step S4) of calculating the mounting error around the two horizontal axes, the following process is performed. That is, the calibration device 10 acquires shape data of the horizontal surface 13a of the surface plate 13, which serves as a calibration member having a leveled horizontal surface 13a, measured by the distance sensor 5 (measured in step S3). Then, the calibration device 10 calculates the mounting error Δθy of the distance sensor 5 around the two horizontal axes by approximating the acquired shape data of the horizontal surface 13a to a linear function and calculating the tilt of the horizontal surface 13a (step S4).

[0045] This makes it possible to calculate the mounting error Δθy around the two horizontal axes of the distance sensor 5 with high accuracy using a simple method. Furthermore, according to the method for calibrating a three-dimensional shape measuring device according to this embodiment, the vertical axis (z s In the calculation process (step S115) for calculating the mounting error around the axis, the following process is performed. That is, the distance sensor 5 measures the calibration block 14 as a calibration member from two different measurement paths a and b, and two pieces of three-dimensional shape measurement data (measurement values in the sensor coordinate system) Σ s For each of these, two coordinate transformation values Σ are obtained by transforming the coordinates for each small angle dθz within the range of ±θ from the design mounting angle θz. r,a , Σ r,b The calibration device 10 then obtains the two coordinate transformation values Σ r,a , Σ r,b The two coordinate transformation values Σ r,a , Σ r,b By calculating the mounting angle at which these values match, the mounting error Δθz of the distance sensor 5 around the vertical axis is calculated (step S115).

[0046] This makes it possible to calculate the mounting error Δθz around the vertical axis of the distance sensor 5 with high accuracy using a simple method. Furthermore, the three-dimensional shape measuring device 12 according to this embodiment includes a distance sensor 5 as a three-dimensional shape measuring device for measuring the three-dimensional shape of an object to be measured, and a calibration device 10. The calibration device 10 calibrates the three mounting direction axes (horizontal axis (x s axis), two horizontal axes (y s axis), and vertical axis (z s For the horizontal axis (x axis), there are three mounting directions. s axis), two horizontal axes (y s axis), and vertical axis (z s When calculating each of these installation errors Δθx, Δθy, Δθz, the installation direction axis (horizontal axis (x s axis), two horizontal axes (y s axis), and vertical axis (z s A different calculation method is used for each axis.

[0047] This allows the calibration device 10 to calculate the installation error of the distance sensor 5 as a three-dimensional shape measuring device using the optimum calculation method corresponding to each installation direction axis. s axis), two horizontal axes (y s axis), and vertical axis (z s The mounting error around the axis can be calculated with high accuracy. Furthermore, the automatic cutting device 1 as an automatic processing device according to this embodiment includes the above-described three-dimensional shape measuring device 12 and a cutting torch 6 as a processing device that processes the thick plate S as the object to be measured. The distance sensor 5 as a three-dimensional shape measuring device measures the three-dimensional shape of the thick plate S at least one of before and after processing by the cutting torch 6.

[0048] This allows the calibration device 10 of the three-dimensional shape measuring device 12 to accurately calculate the installation error of the distance sensor 5 as a three-dimensional shape measuring device using the optimal calculation method corresponding to each installation direction axis, thereby enabling the three-dimensional shape of at least one of the thick plates S before and after processing by the cutting torch 6 to be measured with high accuracy. Although the embodiment of the present invention has been described above, the present invention is not limited to this and various modifications and improvements can be made. For example, the horizontal axis (x s axis), two horizontal axes (y s axis), and vertical axis (z s It is not necessary to calculate the installation error of the distance sensor 5 for all three axes (x axis), but it is sufficient to calculate the error for only the necessary axes. For example, when cutting a thick plate S by moving a cutting torch 6 installed in the vertical direction (z direction) in the horizontal direction (y direction), the distance sensor 5 is installed in the horizontal direction (x axis). s There is no need to consider the mounting error Δθx around the horizontal two axes (y s axis) and vertical axis (z s Only the installation errors around the two axes (axis) need to be calibrated.

[0049] The axis of the distance sensor 5 is horizontal (x s axis), two horizontal axes (y s axis), and vertical axis (z s However, it is not limited to three axes, and multiple axes are acceptable. In addition, although the case where distance sensor 5 as a three-dimensional measuring device is attached to automatic cutting device 1 and a thick plate S as a measurement object is cut has been described, it is also possible to install three-dimensional shape measuring device 12 independently. Also, three-dimensional shape measuring device 12 can be attached to various automatic processing devices for measurement objects other than automatic cutting device 1. Furthermore, the measurement object is not limited to thick plate S, and three-dimensional shape measuring device 12 can be adapted to measure the three-dimensional shapes of various objects.

[0050] Furthermore, the automatic cutting device 1 is not limited to a gate-type cutting machine as long as it is configured to be able to move the cutting torch 6 and the distance sensor 5 relative to the object to be measured. Furthermore, the distance sensor 5 as a three-dimensional shape measuring device measures the three-dimensional shape of the thick plate S as the object to be measured both before and after processing by the cutting torch 6 as a processing device. However, this is not limited to this case, and it is sufficient if the three-dimensional shape of the thick plate S is measured at least either before or after processing. Furthermore, when measuring the three-dimensional shape of a thick plate S using the automatic cutting device 1, as shown in Figure 11, multiple distance sensors 5 may be installed in the width direction of a gate-shaped cart 3, and each of the multiple distance sensors 5 may be scanned only in the direction of arrow B (x direction) to measure the three-dimensional shape of the thick plate S. [Example]

[0051] (1) The horizontal two axes (y s An embodiment in which the mounting angle of a distance sensor around two horizontal axes (y axis) is calibrated will be described with reference to FIG. 12. FIG. 12 shows the calibrated mounting angle of a distance sensor around two horizontal axes (y axis) by the calibration method of the present invention. s 10 is a graph for explaining the effect of an embodiment in which the mounting angle of the distance sensor around the axis is calibrated. The two horizontal axes (y s In the method for calculating the installation error Δθy around the horizontal two axes (y axis), the distance sensor 5 measures the horizontal surface 13a of the leveled surface plate 13, and the calibration device 10 acquires the shape data of the horizontal surface 13a measured by the distance sensor 5. Then, the calibration device 10 calculates the inclination of the horizontal surface 13a by approximating the acquired shape data of the horizontal surface 13a to a linear function. As a result, the inclination of the horizontal surface 13a was found to be 0.51°. This allows the calibration device 10 to calculate the inclination of the horizontal surface 13a around the two horizontal axes (y axis) of the distance sensor 5. s The mounting error Δθy around the axis was calculated to be 0.51°. Then, the worker moves along the horizontal two axes (y s The mounting angle of the distance sensor 5 around the axis was corrected by 0.51°, and the horizontal surface 13a of the surface plate 13 was measured. As a result, as shown in Fig. 12, the inclination of the horizontal surface 13a of the surface plate 13 was found to be close to 0°.

[0052] (2) The vertical axis (z sAn embodiment in which the mounting angle of a distance sensor around the vertical axis (z axis) is calibrated will be described with reference to Figs. 13 to 15. Fig. 13 shows the calibration method of the present invention. s 14(a) is an explanatory diagram showing three-dimensional shape measurement data obtained by measuring the square along the measurement path a shown in FIG. 13. FIG. 14(b) is an explanatory diagram showing three-dimensional shape measurement data obtained by measuring the square along the measurement path b shown in FIG. 13. FIG. 15(a) is a diagram superimposing coordinate transformation values obtained by converting the three-dimensional shape measurement data obtained by measuring the square along the measurement path a shown in FIG. 13 at a designed distance sensor mounting angle θz = 45° onto coordinate transformation values obtained by converting the three-dimensional shape measurement data obtained by measuring the square along the measurement path b shown in FIG. 13 at a designed distance sensor mounting angle θz = 45°. Figure 15(b) is a diagram superimposing coordinate copyright values obtained by transforming the three-dimensional shape measurement data measured with a square using measurement path a shown in Figure 13 at an installation angle of 42.5°, which is a change of Δθz = -2.5° from the designed installation angle of the distance sensor θz = 45°, and coordinate transformation values obtained by transforming the three-dimensional shape measurement data measured with a square using measurement path b shown in Figure 13 at an installation angle of 42.5°, which is a change of Δθz = -2.5° from the designed installation angle of the distance sensor θz = 45°.

[0053] The vertical axis (z s In the method for calculating the mounting error Δθz around the axis, the distance sensor 5 measured the square T from measurement paths a and b in two different, perpendicular directions, as shown in Fig. 13. As a result, the measurement value (three-dimensional shape measurement data) Σa in the sensor coordinate system when the square T was measured along measurement path a shown in Fig. 13 was as shown in Fig. 14(a), and the measurement value (three-dimensional shape measurement data) Σb in the sensor coordinate system when the square T was measured along measurement path b shown in Fig. 13 was as shown in Fig. 14(b). The coordinate conversion unit 5a of the distance sensor 5 converts the measurement value (three-dimensional shape measurement data) Σa of the sensor coordinate system measured by the distance sensor 5 (three-dimensional shape measurement data) Σb into a coordinate conversion value Σa of the moving coordinate system using equation (1) at a designed mounting angle of the distance sensor θz = 45°. r,a , Σ r,b In this case, the mounting angle θx of the distance sensor in the design was set to 0°, and θy was set to 0°.

[0054] Then, the calibration device 10 calculates both of the calculated coordinate transformation values Σ r,a , Σ r,b were obtained and superimposed as shown in Figure 15(a). As a result, both coordinate transformation values Σ r,a , Σ r,b There was an error of 4.07 mm between them. Furthermore, the coordinate conversion unit 5a of the distance sensor 5 converts the measurement value (three-dimensional shape measurement data) Σa of the sensor coordinate system measured by the distance sensor 5 (three-dimensional shape measurement data) Σb into a coordinate conversion value Σ of the moving coordinate system using equation (1) with the designed mounting angle of the distance sensor θz: 45° - mounting error Δθz: 2.5° = 42.5°. r,a ', Σ r,b In this case, the mounting angle θx of the distance sensor in design remains 0°, and θy remains 0°. Then, the calibration device 10 calculates both coordinate transformation values Σ r,a ', Σ r,b ' and superimposed them as shown in Figure 15(b). As a result, both coordinate transformation values Σ r,a ', Σ r,b The error between the vertical axis (z s The mounting error Δθz around the axis was calculated to be 2.5°. And the vertical axis (z s The mounting angle of the distance sensor 5 around the axis was corrected by 2.5°.

[0055] (3) Next, with reference to Figures 16 to 18, a comparative example will be described in which the shape of the thick plate S after cutting is measured before the mounting angle of the distance sensor 5 is calibrated in the automatic cutting device 1 shown in Figure 1, and an example will be described in which the shape of the thick plate S after cutting is measured after the mounting angle of the distance sensor 5 is calibrated in the automatic cutting device 1 shown in Figure 1. Fig. 16 is a diagram illustrating a method for measuring the shape of a thick plate in a comparative example in which the shape of the thick plate after cutting is measured before the mounting angle of the distance sensor 5 is calibrated in the automatic cutting device 1 shown in Fig. 1, and an example in which the shape of the thick plate after cutting is measured with the mounting angle of the distance sensor 5 calibrated in the automatic cutting device 1 shown in Fig. 1. Fig. 17 is a graph showing the measurement results in the comparative example. Fig. 18 is a graph showing the measurement results in the example. In the comparative example, in Fig. 16, before the mounting angle of the distance sensor 5 was calibrated, the shape of the thick plate S after cutting was measured along the direction indicated by the arrow C, and the longitudinal dimension lx and width dimension ly of the thick plate S were determined. Then, the shape of the thick plate S after cutting was measured manually using a tape measure, and the longitudinal dimension Lx and width dimension Ly of the thick plate S were determined.

[0056] The difference between Lx and Ly measured manually using a tape measure and lx and ly measured using the method of the comparative example was taken as the measurement errors dx and dy. dx=Lx-lx dy=Ly-ly The results of the measurement errors dx and dy are shown in FIG.

[0057] [Table 1]

[0058] As shown in FIG. 17 and Table 1, the measurement errors dx and dy between Lx and Ly obtained by manual measurement using a tape measure and lx and ly obtained by measurement using the method of the comparative example were very large, with the maximum measurement error dx being approximately 3 mm and the maximum measurement error dy being approximately 7.5 mm. In contrast to this, in the example shown in Figure 16, after the installation angle of the distance sensor 5 was calibrated, the shape of the thick plate S after cutting was measured along the direction indicated by arrow C, and the longitudinal dimension lx and width dimension ly of the thick plate S were obtained. Then, the shape of the thick plate S after cutting was measured manually using a tape measure, and the longitudinal dimension Lx and width dimension Ly of the thick plate S were obtained. The difference between Lx and Ly measured manually using a tape measure and lx and ly measured by the method according to the embodiment was taken as the measurement errors dx and dy. dx=Lx-lx dy=Ly-ly The results of the measurement errors dx and dy are shown in FIG.

[0059] [Table 2]

[0060] As shown in FIG. 18 and Table 2, the measurement errors dx and dy between Lx and Ly obtained by manual measurement using a tape measure and lx and ly obtained by measurement using the method of the embodiment were approximately 0.86 mm at maximum and approximately 0.96 mm at maximum, confirming that the measurement errors were reduced compared to the comparative example. [Explanation of symbols]

[0061] 1 Automatic cutting device (automatic processing device) 1a Pedestal 2 Rails 3 carts 4 Tools 5. Distance sensor (3D shape measurement device) 5a Coordinate conversion section 5b Optical axis 5c Laser light 6 Cutting torch (processing equipment) 7 Mounting angle adjustment mechanism 7a Rotation axis 7b Rotation axis 7c rotation axis 8 Control Device 9 Control Unit 10 Calibration device 10a Installation error calculation section 10b Installation error output section 11 Output section 12 3D shape measuring device 13 Surface plate (calibration material) 13a horizontal plane 14 Calibration block (calibration member) 14a horizontal plane 14b horizontal plane S Thick plate (object to be measured)

Claims

1. 1. A calibration method for a three-dimensional shape measuring device for calibrating an installation error of the three-dimensional shape measuring device for measuring the three-dimensional shape of an object to be measured, comprising: a calculation step of calculating, by a calibration device, an installation error around each of a plurality of installation direction axes of the three-dimensional shape measuring device using a different calculation method for each of the installation direction axes; the three-dimensional shape measuring device is a distance sensor that irradiates a line-shaped laser beam onto the object to be measured and measures the distance to the object to be measured, and the multiple mounting direction axes are three axes: a horizontal axis that is horizontal and in the line direction of the laser beam, two horizontal axes that are horizontal and perpendicular to the horizontal axis, and a vertical axis that is parallel to the laser beam and perpendicular to the horizontal axis and the two horizontal axes; In the calculation step of calculating the installation error of the three-dimensional shape measuring device about the vertical axis by the calibration device, the calibration device acquires two coordinate transformation values by performing coordinate transformation for each small angle dθz in a range of ±θ from the design installation angle θz for each of two three-dimensional shape measurement data obtained by the three-dimensional shape measuring device measuring a calibration member from two different measurement paths, and then calculates the installation error Δθz about the vertical axis of the three-dimensional shape measuring device by superimposing the two coordinate transformation values acquired by the calibration device.

2. 2. The calibration method for a three-dimensional shape measuring instrument according to claim 1, wherein in the calculation step of calculating the installation errors of the three-dimensional shape measuring instrument about the two horizontal axes by the calibration device, the calibration device acquires shape data of the horizontal plane of a calibration member having a leveled horizontal surface measured by the three-dimensional shape measuring instrument, and calculates the installation error Δθy of the three-dimensional shape measuring instrument about the two horizontal axes by approximating the shape data of the horizontal plane acquired by the calibration device to a linear function to calculate the tilt of the horizontal plane.

3. a three-dimensional shape measuring device for measuring the three-dimensional shape of an object to be measured; a calibration device that calculates an installation error around each of a plurality of installation direction axes of the three-dimensional shape measuring device using a different calculation method for each of the installation direction axes, the three-dimensional shape measuring device is a distance sensor that irradiates a line-shaped laser beam onto the object to be measured and measures the distance to the object to be measured, and the multiple mounting direction axes are three axes: a horizontal axis that is horizontal and in the line direction of the laser beam, two horizontal axes that are horizontal and perpendicular to the horizontal axis, and a vertical axis that is parallel to the laser beam and perpendicular to the horizontal axis and the two horizontal axes; a calibration device for calculating an installation error about the vertical axis of the three-dimensional shape measuring instrument by the calibration device, the calibration device acquiring two coordinate transformation values by performing coordinate transformation for each small angle dθz in a range of ±θ from the design installation angle θz for each of two pieces of three-dimensional shape measurement data obtained by the three-dimensional shape measuring instrument measuring a calibration member from two different measurement paths, and then superimposing the two coordinate transformation values acquired by the calibration device to calculate an installation angle at which the two coordinate transformation values coincide, thereby calculating an installation error Δθz about the vertical axis of the three-dimensional shape measuring instrument.

4. a three-dimensional shape measuring device including: a three-dimensional shape measuring device that measures the three-dimensional shape of an object to be measured; and a calibration device that calculates installation errors about a plurality of installation direction axes of the three-dimensional shape measuring device using different calculation methods for each of the installation direction axes; a processing device for processing the object to be measured, the three-dimensional shape measuring device measures the three-dimensional shape of the object to be measured at least one of before and after processing by the processing device, the three-dimensional shape measuring device is a distance sensor that irradiates a line-shaped laser beam onto the object to be measured and measures the distance to the object to be measured, and the multiple mounting direction axes are three axes: a horizontal axis that is horizontal and in the line direction of the laser beam, two horizontal axes that are horizontal and perpendicular to the horizontal axis, and a vertical axis that is parallel to the laser beam and perpendicular to the horizontal axis and the two horizontal axes; the calibration device acquires two coordinate transformation values obtained by coordinate transformation for each small angle dθz in a range of ±θ from the design mounting angle θz for each of two pieces of three-dimensional shape measurement data obtained by the three-dimensional shape measuring device measuring a calibration member from two different measurement paths, and then superimposes the two coordinate transformation values acquired by the calibration device to calculate the mounting angle at which the two coordinate transformation values match, thereby calculating the mounting error Δθz of the three-dimensional shape measuring device about the vertical axis.

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