JP4552907B2 - Form measuring device deviation amount acquisition method, deviation amount acquisition program, and deviation amount acquisition reference workpiece - Google Patents

Description

  The present invention relates to a deviation from a reference coordinate system of a coordinate system defined in a shape measuring instrument that irradiates light toward a measurement object and receives reflected light to measure the external shape of the measurement object. The present invention relates to a method for acquiring an amount, a program used for acquiring the amount of deviation, and a reference work (object for acquiring an amount of deviation) used for acquiring the amount of deviation.

  When measuring the external shape of a measurement object with a shape measuring instrument, the coordinate system (camera coordinate system) defined in the shape measuring instrument is different from the reference coordinate system (reference coordinate system) defined by the measurement object. If shape measurement is performed in such a state, a relative error occurs between the measurement data and the CAD data of the measurement object, and it is evaluated whether the measurement object is correctly designed. It cannot be done properly. In order to prevent such a problem, calibration of the shape measuring instrument is performed before the shape measurement, the amount of deviation of the camera coordinate system from the reference coordinate system is acquired, and the posture and position of the shape measuring instrument are corrected. .

With respect to such calibration, Patent Document 1 discloses a method of performing calibration by measuring a reference workpiece having a plurality of reference positions with a shape measuring instrument and adjusting the relative relationship between the plurality of reference positions. Are listed.
Japanese Patent Laid-Open No. 03-187579

  The method described in Patent Document 1 can be applied when shape measurement is performed by capturing an entire image at once by a CCD camera. However, a method of measuring the entire outer shape by repeatedly performing two-dimensional measurement, for example, irradiating the measurement target with light in a slit shape or linearly scanning with laser light or the like. Thus, when shape measurement is performed by a method of measuring the shape from position information in the irradiated portion, it is difficult to grasp the reference position by a single scan. Therefore, the method described in Patent Document 1 is unsuitable for calibration with respect to those performing this kind of shape measurement method.

  The present invention has been made to cope with the above problem, and its purpose is efficiency in the case of performing a shape measuring method for measuring the outer shape of a measurement object by irradiating the measurement object with light in a straight line. For obtaining a deviation amount of a camera coordinate system with respect to a typical reference coordinate system, a deviation amount acquisition program for realizing the method, and a deviation amount acquisition reference required for executing such deviation amount acquisition The object is to provide a workpiece (an object for obtaining a deviation amount).

  In order to achieve the above object, the feature of the present invention is that the measurement object is measured by linearly irradiating the measurement object and receiving the reflected light of the irradiated light and calculating the coordinate point of the received reflected light. A shape measuring instrument shift amount acquisition method for acquiring a shift amount of a shape measuring instrument for measuring a three-dimensional shape of a target object with respect to the measurement target, wherein the first direction defines a z axis whose normal direction is one coordinate axis. A plane part and a second plane part defining an x-axis that is a coordinate axis perpendicular to the z-axis, and a plane perpendicular to the z-axis and the first plane part Y has a third plane portion and a fourth plane portion where intersecting lines are formed on different planes, and is a coordinate axis orthogonal to the z-axis, the x-axis, and both the z-axis and the x-axis For a reference workpiece that defines a reference coordinate system (reference coordinate system) by axis An irradiation step of irradiating light linearly so as to pass through the first plane portion, the second plane portion, the third plane portion, and the fourth plane portion, and the light irradiated on the reference workpiece in the irradiation step Point cloud data acquisition step for acquiring point cloud data of the coordinate point of the irradiation point irradiated on the reference workpiece in the coordinate system (camera coordinate system) defined in the shape measuring instrument by the information obtained from the reflected light of A deviation for detecting a deviation amount of the coordinate system (camera coordinate system) defined in the shape measuring instrument with respect to the reference coordinate system (reference coordinate system) based on the point cloud data obtained in the point cloud data obtaining step. And a method of obtaining a deviation amount of the shape measuring instrument including the amount detection step.

  According to the method of the present invention described above, by irradiating the reference workpiece linearly so as to pass through the first plane portion, the second plane portion, the third plane portion and the fourth plane portion of the reference workpiece, Information on the position of the light irradiated on each flat surface portion can be acquired. Here, since the reference workpiece can define a reference coordinate system by the first plane portion, the second plane portion, the third plane portion, and the fourth plane portion, each of the plane portions is irradiated. From the information regarding the position of the light, it is possible to detect the shift amount of the coordinate system defined in the shape measuring instrument with respect to the coordinate system serving as a reference defined by the reference workpiece. In this way, the deviation amount of the shape measuring instrument can be acquired.

  In this case, the intersecting line may be parallel to the y-axis. Further, the shift amount detection step includes, based on the point cloud data acquired in the point cloud data acquisition step, the first plane part, the second plane part, and the first plane part in a coordinate system defined in the shape measuring instrument. A straight line calculation step for calculating a straight line equation indicating a cutting line of light irradiated on any two or more plane portions of the three plane portions and the fourth plane portion, and two or more calculated in the straight line calculation step And a shift amount calculating step for calculating the shift amount based on the straight line equation. The amount of deviation can be derived from the cutting line of the light applied to each plane portion by the geometric relationship. In addition, in order to obtain | require a linear equation from point cloud data, it can calculate by the least squares method etc. based on the coordinate point of the point cloud data acquired in each plane part.

  The deviation amount includes a deviation angle and a deviation position. The deviation angle is the angle formed by the coordinate axis of the coordinate system defined in the shape measuring instrument with respect to the coordinate axis of the reference coordinate system, specifically, the x-axis, y-axis, and z-axis defined by the reference workpiece In addition, there are displacement angles θx, θy, and θz, which are angles at which the coordinate axes of the coordinate system defined in the shape measuring instrument are inclined. The displacement position is a displacement amount of the coordinate axis of the coordinate system defined in the shape measuring instrument with respect to the coordinate axis of the reference coordinate system, and specifically, in the x-axis, y-axis, and z-axis directions defined by the reference workpiece. Displacement positions Δx, Δy, and Δz, which are displacement amounts of coordinate axes of the coordinate system defined in the shape measuring instrument.

  In calculating the deviation angle θx, in the straight line calculation step, the point cloud data of the irradiation point in the first plane part, the point cloud data of the irradiation point in the third plane part, and the fourth plane part From the point cloud data of the irradiation point, the equation of the first straight line showing the cutting line of the light irradiated to the first plane part in the coordinate system defined by the shape measuring instrument, the cutting line of the light irradiated to the third plane part And a third straight line equation indicating a cutting line of light irradiated on the fourth plane part, and calculating the first straight line equation calculated in the deviation amount calculating step, The shift angle θx can be calculated by calculating the shift angle θx based on the equation of the three lines and the equation of the fourth line.

  Further, in calculating the deviation angle θz, in the straight line calculation step, from the point cloud data of the irradiation point in the first plane part and the point cloud data of the irradiation point in the second plane part to the shape measuring instrument. Calculate the equation of the first straight line indicating the cutting line of the light irradiated to the first plane part and the equation of the second straight line indicating the cutting line of the light irradiated to the second plane part in the defined coordinate system, and the deviation In the quantity calculation step, the deviation angle θz can be calculated by calculating the deviation angle θz based on the calculated equation of the first straight line and the equation of the second straight line.

  In calculating the displacement position Δy, in the straight line calculation step, from the point cloud data of the irradiation point in the first plane part and the point cloud data of the irradiation point in the second plane part, Calculate the equation of the first straight line indicating the cutting line of the light irradiated to the first plane part and the equation of the second straight line indicating the cutting line of the light irradiated to the second plane part in the defined coordinate system, and the deviation In the quantity calculating step, the shift position Δy can be calculated by calculating the shift position Δy based on the calculated equation of the first straight line and the equation of the second straight line.

  In calculating the deviation angle θy, in the straight line calculation step, the point cloud data of the irradiation point in the first plane part, the point cloud data of the irradiation point in the third plane part, and the fourth plane part From the point cloud data of the irradiation point, the equation of the first straight line showing the cutting line of the light irradiated to the first plane part in the coordinate system defined by the shape measuring instrument, the cutting line of the light irradiated to the third plane part And an equation of a fourth straight line indicating a cutting line of light irradiated on the fourth plane portion, and calculating the first straight line equation calculated in the deviation amount calculating step, The deviation angle θy can be calculated by calculating the deviation angle θy based on the equation of the three lines and the equation of the fourth line.

  Further, in calculating the displacement position Δx, in the straight line calculation step, from the point cloud data of the irradiation point in the third plane part and the point cloud data of the irradiation point in the fourth plane part to the shape measuring instrument. Calculate the deviation of the third straight line equation indicating the cutting line of the light irradiated to the third plane portion in the defined coordinate system and the fourth straight line equation indicating the cutting line of the light irradiated to the fourth plane portion, and shift them. In the quantity calculation step, the shift position Δx can be calculated by calculating the shift position Δx based on the calculated equation of the third straight line and the equation of the fourth straight line.

  Further, in calculating the displacement position Δz, in the straight line calculation step, from the point cloud data of the irradiation point in the third plane part and the point cloud data of the irradiation point in the fourth plane part, Calculate the deviation of the third straight line equation indicating the cutting line of the light irradiated to the third plane portion in the defined coordinate system and the fourth straight line equation indicating the cutting line of the light irradiated to the fourth plane portion, and shift them. In the quantity calculation step, the shift position Δz can be calculated by calculating the shift position Δz based on the calculated equation of the third straight line and the equation of the fourth straight line.

  In this case, it is preferable to calculate the deviation angles θx, θy, θz, and deviation positions Δx, Δy, Δz sequentially by the above method, and to calculate deviation amounts at all angles and positions. At this time, it is preferable to correct the posture of the shape measuring instrument automatically or manually so that the calculated amount of deviation is zero after the calculation of each amount of deviation. Further, when the correction is made, it is preferable to perform the irradiation step and the point cloud data acquisition step each time to reacquire the point cloud data. In this way, the position and inclination of the shape measuring instrument with respect to the measurement object can be accurately corrected. In addition, it is preferable to obtain the deviation angle and obtain the inclination of the shape measuring instrument before obtaining the deviation position. If the shift amount is acquired and corrected in this order, it is possible to prevent the shift of the shift amount due to the correction from being adversely affected.

  Hereinafter, embodiments of the present invention will be described. FIG. 1 shows an overall schematic diagram of a shape measuring system according to the present embodiment. As shown in FIG. 1, the shape measuring system of the present embodiment includes a shape measuring device 10 and an attitude control device 20. The shape measuring instrument 10 measures the three-dimensional surface shape of an object located on the front side of the object and outputs information representing the measured three-dimensional surface shape. For example, according to the triangulation method using laser light. It measures the three-dimensional surface shape of an object.

  The outer shape of the shape measuring instrument 10 is constituted by a rectangular housing 11. In the housing 11, a laser light source, an irradiation direction changing device, and a light receiving device are accommodated. The laser light source emits laser light to the outside, and any kind of laser light source can be used as long as stimulated emission is possible, but miniaturization can be achieved by using a laser diode. The irradiation direction changing device changes the emission direction of the laser light emitted from the laser light source to the horizontal direction, and may have any structure as long as it has such a function. For example, a mechanism that swings the laser light source itself in the horizontal direction can also be used. Alternatively, the irradiation direction changing device may be configured by a galvano mirror and an electric motor that swings the galvano mirror about a vertical axis, and the optical path of the laser beam is changed in the horizontal direction by the swing of the galvano mirror. it can. The light receiving device receives scattered light scattered on the surface of the measurement object when the measurement object is irradiated with laser light, and generates an electrical signal. CCDs (Charge Coupled Devices) and the like are arranged in a line. A line sensor or the like is used. In addition, an optical device for improving the light receiving accuracy, for example, an imaging lens for forming an image of scattered light from the measurement object on the light receiving device is appropriately disposed in the housing.

  The posture control device 20 includes a support unit 21, a position adjuster 22 attached to the upper end of the support unit 21, and an angle adjuster 23 disposed on the upper surface of the position adjuster 22. The column unit 21 includes an outer cylinder 211 and an inner cylinder 212 inserted into the outer cylinder 211 so as to be movable in the axial direction. The inner cylinder 212 is rotatable in the direction around the axis within the outer cylinder 211. A screw hole 211a is formed in the side periphery of the outer cylinder 211, and a bolt 211b is attached to the screw hole 211a. Therefore, the axial movement and rotation of the inner cylinder 212 in the outer cylinder 211 can be restricted by rotating the bolt 211 b and bringing the tip of the bolt 211 b into contact with the outer periphery of the inner cylinder 212.

  As shown in the figure, the position adjuster 22 is configured in a rectangular parallelepiped shape, and a first slit 221 and a second slit 222 are formed on two side surfaces of the four side surfaces. In addition, a first lever 223 and a second lever 224 are attached to the position adjuster 22, and the first lever 223 is connected to a link mechanism (not shown) incorporated in the position adjuster 22 through the first slit 221. The second lever 224 is connected to the link mechanism through the second slit 222. The link mechanism is connected to the lower surface of the angle adjuster 23 so that the angle adjuster 23 can be moved in the front-rear and left-right directions. Therefore, by moving the first lever 223 in the horizontal direction along the first slit 221, the angle adjuster 23 connected to the link mechanism is against the measurement object facing the front of the shape measuring instrument 10. Move left and right. Further, by moving the second lever 224 in the horizontal direction along the second slit 222, the angle adjuster 23 moves in the front-rear direction with respect to the measurement object.

  In the present embodiment, the angle adjuster 23 is formed by overlapping two disk-shaped members (a lower disk member 231 and an upper disk member 232) at a predetermined interval. Both the lower disk member 231 and the upper disk member 232 have the same disk shape. The bottom disc member 231 has three bottomed holes 231a formed at equal intervals in the circumferential direction. The bottomed hole 231a opens at the upper surface of the lower disk member 231 and is closed at the lower surface. Three screw holes 232a are formed through the upper disk member 232 at equal intervals in the circumferential direction. The bottomed holes 231a and the screw holes 232a are aligned in the vertical direction of the bottomed holes 231a and the screw holes 232a when the lower disk member 231 and the upper disk member 232 are vertically stacked. The lower disk member 231 and the upper disk member 232 are respectively formed so as to be able to take a state to be performed. And both the disk members 231 and 232 are overlapped so as to be in the above state. Further, a bolt 233 is attached to the bottomed hole 231a and the screw hole 232a whose axial centers coincide with each other in the vertical direction.

  As the bolt 233 rotates, the screwed state of the bolt 233 and the screw hole 232a changes, and the relative height position of the upper disk member 232 with respect to the lower disk member 231 is changed. Therefore, the inclination of the upper disk member 232 is adjusted by independently rotating the bolts 233 attached to the bottomed holes 231a and the screw holes 232a. As shown in the figure, since the shape measuring instrument 10 is placed on the upper surface of the upper disk member 232, the inclination of the shape measuring instrument 10 with respect to the measurement object can be adjusted by rotating each bolt 233. .

  The measurement object is arranged to face the front of the shape measuring instrument 10. In the present embodiment, the measurement object is a rotating object having an axis, such as a crankshaft used in a vehicle. When actually measuring the external shape of such an object to be measured using the shape measuring system of this embodiment, the shape measuring instrument 10 linearly emits laser light in a direction along the axis of the object to be measured. Irradiate and measure the cross-sectional profile through the axis of the measurement object. At the same time, the measuring object rotates around its own axis. By measuring in this way, it is possible to measure the cross-sectional outline of the entire measurement object. In performing such shape measurement, a support mechanism that supports the axis of the measurement object in a horizontal state is necessary. In the present embodiment, the support mechanism 30 is composed of two long plate-like members 31, 31 erected facing each other at a predetermined interval. On the upper surface of the long plate-like member 31, a recess 31a is formed which is cut out in a semicircular cross section as shown in FIG. The measurement object is supported so that both end portions of the shaft are respectively placed in recesses 31a formed in the two long plate-like members 31, and the shaft is horizontal.

  As described above, when measuring the outer shape of the measurement object, the laser light emitted from the shape measuring instrument 10 is linearly applied to the measurement object along the axis of the measurement object. At this time, if the irradiation direction of the laser beam is deviated or tilted from the position along the axis, it is not possible to measure an accurate outer shape, and it is not possible to evaluate an appropriate outer shape. For this reason, before actually measuring the shape of the measurement object, the outer shape of the reference workpiece is first measured and defined as a shape measuring instrument for the coordinate system (reference coordinate system) that is the reference of the measurement object. It is necessary to acquire the shift amount of the coordinate system (camera coordinate system). When acquiring the deviation amount, a reference workpiece (an object for obtaining deviation amount) 40 as shown in FIG. 1 is placed on the support mechanism 30.

  The reference workpiece 40 includes a shaft part 41, a positioning part 42, and a measurement part 43. The shaft portion 41 has a long rod shape, and both ends thereof are fitted into the recessed portions 31 a formed on the upper surface of the support mechanism 30, and the positions thereof are fixed. The positioning portion 42 is formed in a semi-cylindrical shape in which a hollow cylindrical member is divided in half, and covers the outer periphery of the shaft portion 41 only on the inner periphery at the both ends of the shaft portion 41. Each is attached. Further, the distance between the positioning portions 42 attached to both ends of the shaft portion 41 is equal to the facing distance between the two long plate members 31, 31 constituting the support mechanism 30. Therefore, by placing the portion of the shaft portion 41 to which the positioning portion 42 is attached in the recess 31 a of the support mechanism 30, the planar portion of the positioning portion 42 becomes the upper end surface of the long plate member 31 as shown in FIG. 2. Abut. By this contact, rotation of the shaft portion 41 in the direction around the axis is restricted.

  As shown in FIG. 1, the measuring unit 43 is formed in a flat plate shape, and a surface other than the surface facing the shape measuring instrument 10 is formed flat, but on the surface facing the shape measuring instrument 10. Has six plane portions. These surfaces are a first plane part 43a, a second plane part 43b, a third plane part 43c, a fourth plane part 43d, a fifth plane part 43e and a sixth plane part 43f from the left in the figure, and a shape measuring instrument These surfaces are arranged in a row in the horizontal direction when viewed from the 10 side. FIG. 3A is a front view of the measuring unit 43, FIG. 3B is a plan view, and FIG. 3C is a side view.

  In FIG. 3A, the first flat portion 43a formed at the left end in the drawing and the sixth flat portion 43f formed at the right end in the drawing are formed on the same plane. Further, the first flat surface portion 43a and the sixth flat surface portion 43f are arranged such that the normal vector n1 is directed to the shape measuring instrument 10 in a state where the reference workpiece 40 is supported by the support mechanism 30 as shown in FIG. They are arranged vertically so as to be in the horizontal direction. Here, the direction of the normal vector n1 defines the direction of the z axis in the reference workpiece 40. The sixth plane portion 43f is provided for accurately calculating the first straight line L1 described later, and is omitted if the first straight line L1 can be calculated with high accuracy only by the first plane portion 43a. Also good.

  In FIG. 3A, the second plane part 43b formed on the right side of the first plane part 43a and the fifth plane part 43e formed on the left side of the sixth plane part 43f are formed on the same plane. ing. Further, as shown in FIG. 1, the second plane part 43b and the fifth plane part 43e are inclined in the z-axis direction defined by the reference workpiece 40 from the upper end to the lower end in the figure. In the present embodiment, as shown in FIG. 1, the lower end sides of the second plane portion 43 b and the fifth plane portion 43 e are inclined so as to protrude from the upper end side with respect to the shape measuring instrument 10, but this relationship is reversed. But it ’s okay.

  Further, when the plane on which the first plane portion 43a and the sixth plane portion 43f are formed is the virtual plane A, and the plane on which the second plane portion 43b and the fifth plane portion 43e are formed is the virtual plane B, the virtual plane A is assumed. The plane A and the virtual plane B are different planes, and the direction vector n2 of the line of intersection of the planes A and B is in a relationship orthogonal to the normal vector n1 of the first plane portion 43a and the sixth plane portion 43f. That is, the second plane part 43b and the fifth plane part 43e rotate the first plane part 43a and the sixth plane part 43f by a predetermined angle φ (see FIG. 3C) around an axis orthogonal to the z-axis. There is a relationship. For this reason, the direction of the direction vector n2 defines the direction of the x axis orthogonal to the z axis. Since the directions of the x axis and the z axis are defined in this way, the direction of the y axis orthogonal to these axes is also defined. Note that the fifth plane portion 43e is provided for accurately calculating the second straight line L2 described later, and is omitted if only the second plane portion 43b can calculate the second straight line L2 with high accuracy. May be.

  The 3rd plane part 43c is a surface formed right next to the 2nd plane part 43b in Fig.3 (a), and as shown to FIG.1 and FIG.3 (b), it is z-axis direction from the illustration left end to a right end It is inclined to. Further, the fourth plane portion 43d is a surface formed on the right side of the third plane portion 43c in FIG. 3A, and is inclined in the z-axis direction from the left end to the right end in the drawing similarly to the third plane portion 43c. is doing. In the present embodiment, as shown in FIG. 1, the right end of the third plane portion 43c is inclined so as to protrude toward the shape measuring instrument 10 with respect to the left end, and the left end of the fourth plane portion 43d is relative to the right end. Are inclined so as to protrude toward the shape measuring instrument 10. Therefore, an intersection line 43g between the third plane part 43c and the fourth plane part 43d is formed so as to protrude in the z-axis direction with respect to the shape measuring instrument 10. The intersecting line 43g may be a plane orthogonal to the z axis and formed in a plane different from the virtual plane A.

The normal vector n1 and the direction vector n2 define the directions of the x-axis, y-axis, and z-axis in the reference coordinate system, but the positions of the x-axis, y-axis, and z-axis in the reference coordinate system are coordinate axes in the reference coordinate system. It is defined by defining the origin as follows: The origin of the coordinate axes in the reference coordinate system is parallel to the normal vector n1, and in a straight line parallel to the normal vector n1 passing through the intersection of the plane 43g including the center line lx of the reference work 40 shown in FIG. , The distance from the intersection is defined as a point at a distance of Z ₀ on the shape measuring instrument side. If the distance from the center line of the shaft portion 41 of the reference workpiece 40 to the shape measuring device (more precisely, the distance to the coordinate axis origin of the coordinate system defined in the shape measuring device) is set, the distance Z ₀ is this set value. To the radius of the shaft portion 41 of the reference workpiece 40 and the distance from the plane on which the first plane portion 43a and the sixth plane portion 43f are formed to the intersection line 43g.

  In the present embodiment, the third plane portion 43c is a plane rotated by a predetermined angle ψ (see FIG. 3B) around the y axis with respect to the first plane portion 43a and the sixth plane portion 43f. The fourth plane portion 43d is a plane rotated by a predetermined angle ψ around the y axis with respect to the first plane portion 43a and the sixth plane portion 43f and on the opposite side to the third plane portion 43c. Therefore, the intersection line 43g between the third plane part 43c and the fourth plane part 43d is a straight line parallel to the y-axis. However, the intersecting line 43g is not necessarily parallel to the y axis.

  As shown in FIG. 1, a computer device 51 is electrically connected to the shape measuring instrument 10. The computer device 51 includes a CPU, a ROM, a RAM, a hard disk, and the like. The computer device 51 executes a deviation amount acquisition program, which will be described later, according to an input instruction from an operator, and a deviation amount (angle, Length) is output to the display device 52. The display device 52 includes a display or a printer, and displays or prints the shift amount input from the computer device 51 on the display.

  Next, the control when acquiring the deviation amount of the shape measuring instrument 10 using the reference workpiece 40 configured as described above will be described. First, when an operator inputs an instruction to execute acquisition of the deviation amount of the shape measuring instrument 10 to the computer apparatus 51, the computer apparatus 51 executes the deviation amount acquisition program of FIG. In this case, the deviation amount acquisition program to be executed may be stored in advance in the ROM of the computer device 51, or may be recorded on a recording medium such as a CD-ROM or a flexible disk. However, the information recorded on these recording media may be read and executed.

  The deviation amount acquisition program is started in step S10 of FIG. 4, and a calculation processing program of the deviation angle θx is executed in step S11. As shown in FIG. 12, the deviation angle θx is formed by a line segment LS1 indicating the incident direction of the laser beam from the shape measuring instrument 10 to the reference workpiece 40 in the yz plane defined by the reference workpiece 40 and the z axis. The shift angle θx is an angle, and indicates the angle at which the shape measuring instrument 10 is inclined around the x axis defined by the reference workpiece 40. This θx calculation processing program is shown in the flowchart of FIG.

  The θx calculation processing program is started in step S110 in FIG. 5, and in step S111, the computer apparatus 51 instructs the shape measuring instrument 10 to irradiate laser light. As a result, the shape measuring instrument 10 is activated, and laser light is emitted from the laser light source housed in the housing 11. Further, the emission direction of the laser light emitted from the laser light source is changed along the horizontal direction by the irradiation direction changing device. For this reason, the laser light is emitted linearly substantially along the x-axis direction of the reference workpiece 40. The laser light emitted from the laser light source is the first flat surface portion 43a, the second flat surface portion 43b, the third flat surface portion 43c, the fourth flat surface portion 43d, and the fifth flat surface portion 43e of the reference workpiece 40 facing the shape measuring instrument 10. And it irradiates to the 6th plane part 43f, respectively.

  When laser light is irradiated on each of the above planar portions, the laser light is irregularly reflected at the irradiated portion. The reflected light passes through the imaging lens in the shape measuring instrument 10, and the reflected light imaged by the imaging lens is received by the light receiving device. Further, the light receiving device is disposed in the shape measuring instrument 10 in such a posture that the light receiving position changes according to the distance from the laser light source to the irradiation spot on the reference workpiece 40. Furthermore, the irradiation angle ξ of the laser beam by the irradiation direction conversion device can be obtained by detecting or calculating the rotation angle of an electric motor that drives the galvano mirror, for example. Accordingly, in step S112, the computer device 51 calculates the distance ln from the laser light source to the irradiation spot of the reference workpiece 40 based on the triangulation principle based on the distance information and the angle information.

Then, the computer device 51, at step S113, the x-z coordinate system as viewed from the shape measuring apparatus 10 calculates the respective irradiation spots of the x-z coordinate point _{N (x n, z n)} . The xz coordinate system used at this time is a coordinate system defined by the shape measuring instrument 10, and specifically, the origin position when measuring the distance ln to the irradiation spot is the origin of the coordinate axis, and the laser beam is irradiated. The laser beam irradiation direction when the angle is 0 ° is the z-axis direction, the direction perpendicular to the z-axis and the laser beam irradiation direction is changed is the x-axis direction, and these z-axis and x-axis directions are perpendicular to the z-axis direction. Of the coordinate systems in which the coordinate data is represented by coordinate axes with the direction as the y-axis direction, this is a coordinate system represented by the xz plane (hereinafter, distinguished from the xz coordinate system defined by the reference workpiece 40). Therefore, the xz coordinate system defined in the shape measuring instrument 10 is referred to as a camera xz coordinate system). In this case, since the laser beam scans the reference workpiece 40 substantially horizontally, a plurality of coordinate points N (x _n , z _n ) in the horizontal direction of the reference workpiece 40 are calculated. The calculation of the coordinate point N (x _n , z _n ) can be determined based on the distance ln and the irradiation angle ξ. For example, the coordinate point of the irradiation spot (irradiation point) whose distance is ln and irradiation angle is ξ can be determined as (ln · cos ξ, ln · sin ξ).

Next, in step S114, the computer device 51 calculates equations of three straight lines (first straight line L1, third straight line L3, fourth straight line L4) from the coordinate point N (x _n , z _n ) of the irradiation spot. Here, the coordinate point N (x _n , z _n ) calculated in step S113 is the first, second, third, fourth, and fourth of the reference workpiece 40 as shown in FIG. 11 in the camera xz coordinate system. The cross-sectional outlines of the fifth and sixth plane portions 43a, 43b, 43c, 43d, 43e, and 43f are scanned. In this case, when the irradiation spot is switched from the first plane portion 43a to the second plane portion 43b, or when the irradiation spot is switched from the second plane portion 43b to the third plane portion 43c, the coordinates at the time of switching A large shift occurs in the points. Therefore, when this deviation (distance between adjacent coordinate points) is less than a predetermined value, it is recognized as point cloud data within the same plane portion, and when the deviation is greater than or equal to a predetermined value, point cloud data within the same plane portion. Recognize it is not. By performing such recognition for each adjacent coordinate point, the point group data G1 belonging to the first plane part 43a, the point group data G2 belonging to the second plane part 43b, and the point group data G3 belonging to the third plane part 43c. The point group data G4 belonging to the fourth plane part 43d, the point group data G5 belonging to the fifth plane part 43e, and the point group data G6 belonging to the sixth plane part 43f can be acquired.

After the point cloud data is acquired separately for each plane portion as described above, the point cloud data G1 belonging to the first plane portion 43a and the point cloud data G6 belonging to the sixth plane portion 43f are used to obtain the second by the least square method. The equation of the straight line L1 is calculated. Further, the equation of the third straight line L3 is calculated by the least square method using the point cloud data G3 belonging to the third plane part 43c. Further, the equation of the fourth straight line L4 is calculated by the least square method using the point cloud data G4 belonging to the fourth plane part 43d. In the present embodiment, the equations of the first, third, and fourth straight lines L1, L3, and L4 are expressed as the following equations 1, 3, and 4, respectively. The equation of the second straight line L2 calculated by the least square method using the point group data G2 belonging to the second plane part 43b and the point group data G5 belonging to the fifth plane part 43e is as shown in the following formula 2. Let's represent.

Next, in step S115, the computer device 51 calculates the coordinate point C (x _c , z _c ) of the intersection of the third straight line L3 and the fourth straight line L4. The coordinate point C can be solved by combining the equation of the third straight line L3 (Equation 3) and the equation of the fourth straight line L4 (Equation 4), and the solution is as shown in Equation 5 below.

Next, in step S116, the computer device 51 calculates the distance S between the coordinate point C (x _c , z _c ) and the first straight line L1. The distance S is obtained from the formula of the distance between the point and the straight line, and is expressed by the following formula 6.

Subsequently, the computer device 51 calculates the shift angle θx using the distance S in step S117. In this case, the shift angle θx is an angle formed by the line segment LS1 indicating the incident direction of the laser beam on the reference workpiece 40 in FIG. 12 and the z axis defined by the reference workpiece 40 as described above. The coordinate point C of the intersection is the coordinate point of the intersection of the line segment LS1 and the intersection line 43g in the figure, and the distance S is the first plane portion 43a and the sixth plane from the coordinate point C in the line segment LS1. The distance to the plane on which the portion 43f is formed is shown. Since the shortest distance from the intersection line 43g to the plane on which the first flat surface portion 43a and the sixth flat surface portion 43f are formed can be measured from the reference workpiece 40, if this distance (shortest distance) is m, the deviation angle The sine of θx can be expressed by the ratio of the distance S and the distance m, and using this relationship, the deviation angle θx can be calculated as shown in Equation 7 below.

  After calculating the deviation angle θx in this way, the computer device 51 ends the execution of the θx calculation processing program in step S118. The obtained deviation angle θx is displayed on the display device 52. The operator adjusts the inclination of the shape measuring instrument 10 by rotating the bolt 233 attached to the angle adjuster 23 so that the displayed deviation angle θx becomes zero. As a result, the shift angle θx is adjusted. Since the above equation 7 can be directly calculated from the equations of m and the first, third and fourth straight lines L1, L3 and L4, these coefficients are used after the equations of each straight line are determined. If the deviation angle θx is directly calculated by Equation 7, the above Equations 5 and 6 can be omitted. As described above, the shift angle θx is the equation of the first straight line L1 that is the cutting line of the laser light in the first flat surface portion 43a and the sixth flat surface portion 43f, and the third straight line that is the cutting line of the laser light in the third flat surface portion 43c. It can be obtained based on the equation of L3 and the equation of the fourth straight line L4 that is the cutting line of the laser beam in the fourth plane portion 43d.

  Since the distance S and the distance m have only positive values in the above formula 7, θx is always a positive value, and the incident direction of the laser light on the reference workpiece 40 is θx above the z axis defined by the reference workpiece 40. It cannot be determined from the calculated shift angle θx whether it is shifted or shifted downward by θx. Accordingly, the operator needs to execute the θx calculation processing program while repeatedly adjusting the deviation angle θx to grasp the direction in which the deviation angle θx is shifted.

After the execution of the θx calculation processing program is completed, the computer device 51 executes the θz calculation processing program in step S12. As shown in FIG. 14, the deviation angle θz is formed by a line segment LS <b> 2 indicating a cutting line from the shape measuring instrument 10 to the reference workpiece 40 on the xy plane defined by the reference workpiece 40 and the x axis. This shift angle θz is an angle at which the shape measuring instrument 10 is inclined around the z axis defined by the reference workpiece 40. A calculation processing program of the shift angle θz is shown in the flowchart of FIG. This θz calculation processing program is started in step S120 of FIG. 6, and laser light is irradiated from the shape measuring instrument 10 to the reference workpiece 40 in step S121. Next, in step S122, the distance ln from the laser light source to the irradiation spot of the reference workpiece 40 is calculated by the principle of triangulation. Subsequently, at step S123, the camera x-z of the radiation spot in a coordinate system x-z coordinate point N (x _n, z _n) to calculate the at step S124, the point cloud data belonging to the first plane portion 43a And the first straight line L1 is calculated based on the point cloud data belonging to the sixth plane part 43f, and the second straight line L2 is calculated based on the point cloud data belonging to the second plane part 43b and the point cloud data belonging to the fifth plane part 43e. calculate. The first straight line L1 and the second straight line L2 can be expressed as in the above formulas 1 and 2.

ここで、θ_L1の正接tanθ_L1は第一直線Ｌ１の傾き（−ａ₁／ｂ₁）に等しく、θ_L2の正接tanθ_L2は第二直線Ｌ２の傾き（−ａ₂／ｂ₂）に等しいので、上記式８は第一直線Ｌ１および第二直線Ｌ２の方程式から計算することができる。なお、θzが０でない場合は、図１４に示すようにレーザー光が基準ワーク４０に対して斜めに照射していることになるので、第二平面部４３ｂおよび第五平面部４３ｅにおける照射スポットのｚ軸方向位置がｘ軸方向に沿って変化し、第一および第六平面部４３ａおよび４３ｆとの相対距離が変化する。このため第二直線Ｌ２が第一直線Ｌ１に交差する。 Next, in step S125, the computer apparatus 51 calculates an angle θ _L1-L2 formed by the first straight line L1 and the second straight line L2. As shown in FIG. 13, the angle θ _{L1 -L2} is an angle formed by the first straight line L1 and the x axis in the camera xz coordinate system is θ _L1, and an angle formed by the second straight line L2 and the x axis is θ _L2. and when equal to the angle theta _L1 - [theta] _L2 of the difference between the angle theta _L1 and the angle theta _L2. Therefore, θ _L1−L2 is calculated by the following equation 8 by the addition theorem of trigonometric functions.

Here, the tangent tan θ _L1 of θ _L1 is equal to the slope (−a ₁ / b ₁ ) of the _first straight line L1, and the tangent tan θ _L2 of θ _L2 is equal to the slope (−a ₂ / b ₂ ) of the second straight line L2. The above equation 8 can be calculated from the equations of the first straight line L1 and the second straight line L2. If θz is not 0, the laser beam is radiated obliquely to the reference workpiece 40 as shown in FIG. 14, so the irradiation spots of the second plane part 43b and the fifth plane part 43e are The z-axis direction position changes along the x-axis direction, and the relative distance between the first and sixth plane portions 43a and 43f changes. For this reason, the second straight line L2 intersects the first straight line L1.

ここで、ｎは、基準ワーク４０のｙ軸方向長さ、ｐは、第二平面部４３ｂおよび第五平面部のｚ軸方向への変化量である（図１４参照）。ｎおよびｐは、基準ワーク４０から測定することができる。上記式９は、以下のように導出される。 Subsequently, in step S126, the computer apparatus calculates θz by executing the calculation of the following formula 9.

Here, n is the length of the reference workpiece 40 in the y-axis direction, and p is the amount of change in the z-axis direction of the second plane part 43b and the fifth plane part (see FIG. 14). n and p can be measured from the reference workpiece 40. Equation 9 is derived as follows.

First, when θz is not 0 and the laser beam is irradiated obliquely with respect to the reference workpiece 40 as shown in FIG. 14, the y-axis of the irradiation spot H at the left end of the second flat portion 43b in the drawing is shown. the height T _H along is different from the height T _J along the y axis of radiation spots J illustrated right end of the fifth flat portion 43e. The difference between both heights is ΔT (= T _H −T _J ). In addition, since the second plane portion 43b and the fifth plane portion 43e are formed to be inclined in the z-axis direction, the depth length (the first length along the z-axis is different if the height position along the y-axis is different. The distance to the plane on which the plane 43a and the sixth plane 43f are formed is also different. Therefore, as shown in FIG. 15 which is an enlarged view of the reference workpiece 40 viewed from the yz plane, the depth length D _H at the irradiation spot _H and the depth length D _J at the irradiation spot J are also different. Let ΔD be the difference between the two depth lengths.

ここで、図１４に示すように、第二平面部４３ｂから第五平面部４３ｅまでのｘ軸方向長さをｑとすると、ｑ’はｑ／cosθzで表されるが、近似的にcosθz＝１とすると、上記式１０は式１１のようになる。

また、相似の関係から、ΔＤとΔＴについて、式１２の関係が成立する。

また、θzの正接tanθzは、図１４から明らかなように下記式１３のように表すことができる。

したがって、式１１を式１２に代入してΔＤを消去し、さらにその式を式１３に代入してΔＴを消去することにより、上記式９が導かれる。 In this case, while the laser beam travels on the reference workpiece 40 from the irradiation spot H to the irradiation spot J (the distance when the laser beam travels from H to J is q ′), the depth length is ΔD. This means that the rate of change is represented by the difference in slope between the first straight line L1 and the second straight line L2, that is, the tangent of θ _L1 -L2. Therefore, the following formula 10 is established.

Here, as shown in FIG. 14, when the length in the x-axis direction from the second plane portion 43b to the fifth plane portion 43e is q, q ′ is expressed by q / cos θz, but approximately cos θz = Assuming 1, Equation 10 above becomes Equation 11.

Further, from the similar relationship, the relationship of Expression 12 is established for ΔD and ΔT.

Further, the tangent tan θz of θz can be expressed as the following Expression 13 as is apparent from FIG.

Therefore, by substituting Equation 11 into Equation 12 to eliminate ΔD, and further substituting the equation into Equation 13 to eliminate ΔT, Equation 9 is derived.

After calculating the deviation angle θz in this way, the computer device 51 ends the execution of the θz calculation processing program in step S127. The obtained deviation angle θz is displayed on the display device 52. The operator rotates each bolt 233 of the angle adjuster 23 so that the displayed deviation angle θz becomes 0, and adjusts the inclination of the shape measuring instrument 10 with respect to the reference workpiece 40. As a result, the shift angle θz is adjusted. In addition, tanθ _L1-L2 in the above equation 9 can also be obtained directly from the equations of the first straight line L1 and the second straight line L2. In this case, the calculation of Equation 8 can be omitted. As described above, the deviation angle θz is the equation of the first straight line L1 that is the cutting line of the laser light in the first plane part 43a and the sixth plane part 43f, and the second that is the cutting line of the laser light in the second plane part 43b. It can be obtained based on the equation of the straight line L2.

After the execution of the θz calculation processing program is completed, the computer device 51 executes the Δy calculation processing program in step S13. As shown in FIG. 17, the shift position Δy includes a center line lx along the x-axis direction in the xy plane of the reference workpiece 40, and a line segment LS <b> 2 indicating a cutting line of the laser light irradiated on the reference workpiece 40. This displacement position Δy indicates the amount by which the shape measuring instrument 10 is displaced in the y-axis direction with respect to the reference workpiece 40. This Δy calculation processing program is started in step S130 of FIG. 7, and laser light is irradiated from the shape measuring instrument 10 toward the reference workpiece 40 in step S131. Next, in step S132, the distance ln from the laser light source to the irradiation spot of the reference workpiece 40 is calculated by the principle of triangulation. Subsequently, at step S133, the camera x-z of the radiation spot in a coordinate system x-z coordinate point N (x _n, z _n) to calculate a first linear L1 in step S134, the equation of the second straight line L2 calculate. The first straight line L1 and the second straight line L2 can be expressed as in the above formulas 1 and 2.

Next, in step S135, the computer apparatus 51 calculates the distance t between the first straight line L1 and the second straight line L2. Here, it is assumed that θz is corrected in the θz calculation program, and the first straight line L1 and the second straight line L2 are in a parallel relationship. The distance t can be obtained by executing the calculation of the following equation (14).

上記式１５は、以下のように導出される。まず、図１７に示すように、距離ｔは、ｙ−ｚ平面における、第二平面部４３ｂおよび第五平面部４３ｅ上へのレーザー光の照射点Ｋから、第一平面部４３ａおよび第六平面部４３ｆが形成される平面までの距離である。一方、Δyは、ｙ−ｚ平面における基準ワーク４０の中心線lxが第二平面部４３ｂおよび第五平面部４３ｅを通過する点Ｌと、上記点Ｋとの間の距離のｙ軸方向成分である。したがって、相似の関係から、ｎ：ｐ＝（ｎ／２−Δy）：ｔとなる。この関係を変形することにより、上記式１５が導かれる。 Subsequently, in step S136, the computer apparatus 51 calculates the displacement position Δy by executing the calculation of the following formula 15.

The above equation 15 is derived as follows. First, as shown in FIG. 17, the distance t is the first plane portion 43 a and the sixth plane from the irradiation point K of the laser beam on the second plane portion 43 b and the fifth plane portion 43 e in the yz plane. This is the distance to the plane on which the portion 43f is formed. On the other hand, Δy is a y-axis direction component of a distance between a point L where the center line lx of the reference workpiece 40 in the yz plane passes through the second plane part 43b and the fifth plane part 43e, and the point K. is there. Therefore, n: p = (n / 2−Δy): t from the similar relationship. The above formula 15 is derived by modifying this relationship.

  After calculating the displacement position Δy in this way, the computer device 51 ends the execution of this Δy calculation processing program in step S137. The obtained shift position Δy is displayed on the display device 52. The operator moves the inner cylinder 212 of the column unit 21 in the axial direction so that the displayed displacement position Δy becomes 0, and adjusts the height of the column unit 21. As a result, the shift position Δy is adjusted. Note that the shift position Δy can also be directly calculated from the equations of the first straight line L1 and the second straight line L2, and in this case, the calculation of the above equation 14 can be omitted. Thus, the shift position Δy is an equation of the first straight line L1 that is a cutting line of the laser light in the first plane part 43a and the sixth plane part 43f, and a second that is a cutting line of the laser light in the second plane part 43b. It can be obtained based on the equation of the straight line L2.

After the execution of the Δy calculation processing program is completed, the computer device 51 executes the θy calculation processing program in step S15. As shown in FIG. 19, the deviation angle θy is a line indicating the incident direction of the laser light when the laser light is incident on the intersecting line 43 g of the reference workpiece 40 from the shape measuring instrument 10 in the xz plane of the reference workpiece 40. The angle formed by the minute LS3 and the z-axis, and the shift angle θy indicates an angle at which the shape measuring instrument 10 is inclined about the y-axis defined by the reference workpiece 40. This θy calculation processing program is started in step S140 of FIG. 8, the laser beam is irradiated from the shape measuring instrument 10 to the reference workpiece 40 in step S141, and the reference workpiece from the laser light source is determined in accordance with the principle of triangulation in step S142. The distance ln to 40 irradiation spots is calculated, the xz coordinate point N (x _n , z _n ) of the irradiation spot in the camera xz coordinate system is calculated in step S143, and the first straight line L1 is calculated in step S144. , The equations of the third straight line L3 and the fourth straight line L4 are calculated. The first straight line L1, the third straight line L3, and the fourth straight line L4 can be expressed as in the above formulas 1, 3, and 4. Thereafter, in step S145, an intersection C (x _c , z _c ) between the third straight line L3 and the fourth straight line L4 is calculated. The intersection point C can be expressed as Equation 5 above.

Next, the computer apparatus 51 calculates the 5th straight line L5 which passes along the intersection C and is perpendicular | vertical to the 1st straight line L1 in step S146. The fifth straight line L5 is orthogonal to the first straight line L1 and can pass through the intersection point C and can be expressed as the following Expression 16.

上記式１７は、上記式１６によって表される第五直線Ｌ５および上記式１によって表される第一直線Ｌ１が共に点Q(x_q,y_q)を通ることに基づいて導かれる。 Subsequently, in step S147, the computer apparatus 51 calculates the coordinate point Q (x _q , y _q ) of the intersection of the fifth straight line L5 and the first straight line L1. The coordinate point Q (x _q , y _q ) is obtained by executing the calculation of Equation 17 below.

The above equation 17 is derived based on the fact that the fifth straight line L5 represented by the above equation 16 and the first straight line L1 represented by the above equation 1 both pass through the point Q (x _q , y _q ).

上記式１８は、以下のようにして導かれる。第一直線Ｌ１，第三直線Ｌ３，第四直線Ｌ４および第五直線Ｌ５がカメラｘ−ｚ座標系において図１８に示す状態のように計測された場合、第三直線Ｌ３と第四直線Ｌ４との交点Cと、第五直線Ｌ５と第一直線Ｌ１との交点Qとを結ぶ線分CQと、カメラｘ−ｚ座標系におけるｚ軸とのなす角がずれ角度θyである。この場合、ずれ角度θyの正弦は、線分ＣＱの長さと、座標点Ｃと座標点Ｑとのｘ軸方向成分の差x_c-x_qとの比によって表される。ここで、線分ＣＱの長さは、基準ワーク４０の交線４３ｇから第一平面部４３ａおよび第六平面部４３ｆが形成される平面までの距離ｍであり、基準ワーク４０から測定することができる。したがって、ずれ角度θyの正弦sinθyは、（x_c−x_q）／ｍと表すことができる。式１８は、この関係に基づき導かれる。 After obtaining the point Q (x _q , y _q ), the computer device 51 calculates θy by executing the following equation 18 in step S148.

The above equation 18 is derived as follows. When the first straight line L1, the third straight line L3, the fourth straight line L4 and the fifth straight line L5 are measured as shown in FIG. 18 in the camera xz coordinate system, the third straight line L3 and the fourth straight line L4 The angle formed by the line segment CQ connecting the intersection C, the intersection Q of the fifth straight line L5 and the first straight line L1, and the z axis in the camera xz coordinate system is the shift angle θy. In this case, the sine of the deviation angle θy is represented by the ratio between the length of the line segment CQ and the difference x _c -x _{q in} the x-axis direction component between the coordinate point C and the coordinate point Q. Here, the length of the line segment CQ is a distance m from the intersection line 43g of the reference workpiece 40 to the plane on which the first plane portion 43a and the sixth plane portion 43f are formed, and can be measured from the reference workpiece 40. it can. Therefore, the sine sin θy of the deviation angle θy can be expressed as (x _c −x _q ) / m. Equation 18 is derived based on this relationship.

After calculating the deviation angle θy in step S148, the computer device 51 ends the execution of the θy calculation processing program in step S149. The obtained shift angle θy is displayed on the display device 52. The operator rotates the inner cylinder 212 of the column unit 21 so that the displayed deviation angle θy becomes zero. As a result, the shift angle θy is adjusted. Note that x _c -x _q in the above equation 18 can also be directly obtained from the equations of the first straight line L1, the third straight line L3, and the fourth straight line L4. Therefore, x _c -x _q is directly calculated from the equations of the first straight line L1, the third straight line L3, and the fourth straight line L4, and θy is calculated without obtaining the fifth straight line L5 and the intersection point Q based on the equation. be able to. In this case, calculation of the above formula 16 and the above formula 17 can be omitted. As described above, the shift angle θy is the equation of the first straight line L1 that is the cutting line of the laser light in the first plane part 43a and the sixth plane part 43f, and the third that is the cutting line of the laser beam in the third plane part 43c. It can be obtained based on the equation of the straight line L3 and the equation of the fourth straight line L4 that is the cutting line of the laser beam in the fourth plane part 43d.

After the execution of the θy calculation processing program is completed, the computer device 51 executes the Δx calculation processing program in step S16. The shift position Δx is a shift amount in the x-axis direction of the shape measuring instrument 10 from the center line lz of the reference workpiece 40 in the xz plane of the reference workpiece 40 as shown in FIG. The Δx calculation processing program is started in step S150 of FIG. 9, and laser light is irradiated from the shape measuring instrument 10 to the reference workpiece 40 in step S151. Next, in step S152, the distance ln from the laser light source to the irradiation spot of the reference workpiece 40 is calculated by the principle of triangulation. Subsequently, in step S153, an xz coordinate point N (x _n , z _n ) of the irradiation spot in the camera xz coordinate system is calculated, and equations of the third straight line L3 and the fourth straight line L4 are calculated in step S154. Calculate The third straight line L3 and the fourth straight line L4 can be expressed as in the above formulas 3 and 4. Thereafter, in step S155, the coordinate point of the intersection C (x _c , z _c ) between the third straight line L3 and the fourth straight line L4 is calculated. The coordinate point of the intersection point C can be calculated as shown in Equation 5 above.

Next, in step S156, the computer apparatus 51 calculates the shift position Δx. In this case, if the time x-axis component at the point of intersection C is zero is a reference position of the x-axis direction of the shape measuring device 10, the x-axis direction component x _c of intersection C calculated in step S155 The amount of deviation in the x-axis direction is shown as it is. Therefore, x _c acquired in the camera xz coordinate system as shown in FIG. 20 is set as a shift position Δx. After calculating the shift position Δx in this way, the computer device 51 ends the execution of the Δx calculation processing program in step S157. The obtained shift position Δx is displayed on the display device 52. The operator adjusts the first lever 223 of the position adjuster 22 so that the displayed displacement position Δx becomes 0 or a predetermined value. As a result, the shift position Δx is adjusted. As described above, the shift position Δx is expressed by the equation of the third straight line L3 that is the cutting line of the laser beam in the third plane portion 43c and the equation of the fourth straight line L4 that is the cutting line of the laser beam in the fourth plane portion 43d. Can be based on.

After the execution of the Δx calculation processing program is completed, the computer device 51 executes the Δz calculation processing program in step S17. As shown in FIG. 21, the displacement position Δz is the difference between the z-axis direction distance z _c from the intersection line 43g to the shape measuring instrument 10 and the reference distance z ₀ in the xz plane of the reference workpiece 40. is there. The Δz calculation processing program is started in step S160 of FIG. 10, and laser light is irradiated from the shape measuring instrument 10 to the reference workpiece 40 in step S161. Next, in step S162, the distance ln from the laser light source to the irradiation spot of the reference workpiece 40 is calculated by the principle of triangulation. Subsequently, at step S163, the camera x-z of the radiation spot in a coordinate system x-z coordinate point N (x _n, z _n) is calculated and the equation of the third straight line L3 and the fourth line L4 at step S164 Calculate The third straight line L3 and the fourth straight line L4 can be expressed as in the above formulas 3 and 4. Thereafter, in step S165, the coordinate point of the intersection C (x _c , z _c ) between the third straight line L3 and the fourth straight line L4 is calculated. The coordinate point of the intersection point C can be calculated as shown in Equation 5 above.

Next, the computer apparatus 51 calculates Δz in step S166. In this case, as shown in FIG. 20, the z-axis direction component z _c at the intersection C is the distance in the z-axis direction from the intersection line 43 g of the reference workpiece 40 to the shape measuring instrument 10. Therefore, the difference between the distance z _c and the reference distance z _{0 in the} z-axis direction becomes the shift position Δz as it is. Therefore, the shift position Δz can be obtained by executing the calculation of z ₀ -z _c . After calculating the shift position Δz in this way, the computer device 51 ends the execution of the Δz calculation processing program in step S167. The obtained shift position Δz is displayed on the display device 52. The operator adjusts the second lever 224 of the position adjuster 22 so that the displayed displacement position Δz becomes zero. As a result, the shift position Δz is adjusted. As described above, the shift position Δz is expressed by the equation of the third straight line L3 that is the cutting line of the laser beam in the third plane portion 43c and the equation of the fourth straight line L4 that is the cutting line of the laser beam in the fourth plane portion 43d. Can be based on.

  As described above, in this embodiment, θx, θy, θz, Δx, Δy, and Δz are detected, and all deviation angles and deviation positions are corrected, thereby measuring the shape in the reference coordinate system defined by the reference workpiece 40. The camera coordinate system of the device 10 can be matched. Therefore, it is possible to measure the shape of the workpiece with extremely high accuracy.

In the above embodiment, the shift angles θx, θy, θz and the shift positions Δx, Δy, Δz are calculated and displayed one by one, and the operator measures the shape based on the displayed shift angle or shift position. Although the example which adjusted the angle and position of the container was shown, it is possible that other shift angles or shift positions will change by adjusting one shift angle or shift position. In this case, the reference workpiece 40 is irradiated with laser light, and the xz coordinate point N (x _n , z _n ) of the irradiation point in the camera xz coordinate system is calculated, and then the deviation angle is calculated by the above calculation method. All of θx, θy, θz and displacement positions Δx, Δy, Δz may be calculated and displayed. When the shift angle or shift position adjusted so as to become zero first shifts from zero again, the operator may perform the previous adjustment work again.

  As mentioned above, although it demonstrated per embodiment of this invention, this invention is not limited to the said embodiment. For example, in the above embodiment, the configuration in which the six plane portions of the reference workpiece 40 are provided is shown, but the fifth plane portion 43e and the sixth plane portion 43f can be omitted. Moreover, it is good also as a structure which replaced the position of the 1st plane part 43a and the 2nd plane part 43b, or the position of the 5th plane part 43e and the 6th plane part 43f. The geometric relationship between the second plane part 43b and the fifth plane part 43e with respect to the first plane part 43a and the sixth plane part 43f is a virtual relationship including the first plane part 43a and the sixth plane part 43f as described above. A virtual plane B including the second plane portion 43b and the fifth plane portion 43e intersects the plane A, and the direction vector n2 of the intersection line is orthogonal to the vector n1 that is also a normal vector of the virtual plane A. As long as such a relationship is satisfied, the second plane portion 43b and the fifth plane portion 43e are formed at positions separated from the first plane portion 43a and the sixth plane portion 43f. Alternatively, these flat portions may intersect within the reference workpiece 40. Further, the intersecting line 43g may be any plane as long as it is a plane orthogonal to the normal vector n1 and located at a position different from the virtual plane A (provided that it is parallel to the direction vector n2). 1), and need not be parallel to the y-axis as shown in FIG. In the above embodiment, the shift angles θx, θy, θz and the shift positions Δx, Δy, Δz are all adjusted, but any important adjustment of the positions may be omitted. For example, if the shift position Δx and the shift position Δz are slightly shifted from 0, the shape measurement of the measurement object may be hardly affected. In such a case, adjustment of the shift angles θx, θy, θz and the shift position Δy may be performed, and adjustment of the shift positions Δx and Δz may be omitted.

1 is an overall schematic diagram of a shape measuring system according to an embodiment of the present invention. It is a figure which shows the part which mounts a reference | standard workpiece in the support mechanism which concerns on embodiment of this invention. It is a figure which shows the reference | standard workpiece | work which concerns on embodiment of this invention, (a) is a front view, (b) is a top view, (c) is a side view. It is a flowchart of the deviation | shift amount acquisition program which concerns on embodiment of this invention. It is a flowchart of the θx calculation program according to the embodiment of the present invention. It is a flowchart of the θz calculation program according to the embodiment of the present invention. 5 is a flowchart of a Δy calculation program according to the embodiment of the present invention. It is a flowchart of the θy calculation program according to the embodiment of the present invention. It is a flowchart of the Δx calculation program according to the embodiment of the present invention. It is a flowchart of (DELTA) z calculation program which concerns on embodiment of this invention. It is a figure which shows the irradiation image of the reference | standard workpiece | work in the camera xz coordinate system measured with the shape measuring device used in execution of a (theta) x calculation program. It is a figure which shows the geometric relationship of the reference | standard workpiece | work for calculating | requiring deviation | shift angle (theta) x. It is a figure which shows the irradiation image of the reference | standard workpiece | work in the camera xz coordinate system measured by the shape measuring device used in execution of a θz calculation program. It is a figure which shows the geometric relationship of the reference | standard workpiece | work for calculating | requiring deviation | shift angle (theta) z. It is an enlarged view showing a geometrical relationship for obtaining a deviation angle θz when the reference workpiece is viewed from the side. It is a figure which shows the irradiation image of the reference | standard workpiece | work in the camera xz coordinate system measured with the shape measuring device used in execution of a (DELTA) y calculation program. It is a figure which shows the geometric relationship of the reference | standard workpiece | work for calculating | requiring deviation | shift position (DELTA) y. It is a figure which shows the irradiation image of the reference | standard workpiece | work in the camera xz coordinate system measured by the shape measuring device used in execution of a θy calculation program. It is a figure which shows the geometric relationship of the reference | standard workpiece | work for calculating | requiring deviation | shift angle (theta) y. It is a figure which shows the irradiation image of the reference | standard workpiece | work in the camera xz coordinate system measured by the shape measuring device used in execution of a (DELTA) x calculation program and a (DELTA) z calculation program. It is a figure which shows the geometric relationship of the reference | standard workpiece | work for calculating | requiring deviation | shift position (DELTA) x and deviation | shift position (DELTA) z.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 ... Shape measuring device, 20 ... Attitude control device, 21 ... Post unit, 22 ... Position adjuster, 23 ... Angle adjuster, 40 ... Reference work, 43 ... Measuring part, 43a ... First plane part, 43b ... Second Plane portion, 43c ... third plane portion, 43d ... fourth plane portion, 43e ... fifth plane portion, 43f ... sixth plane portion, 43g ... intersection line, 51 ... computer device, 52 ... display device, L1 ... first straight line , L2 ... second straight line, L3 ... third straight line, L4 ... fourth straight line, L5 ... fifth straight line, Δx, Δy, Δz ... deviation position, θx, θy, θz ... deviation angle

Claims (13)

A shape measuring instrument that measures the three-dimensional shape of a measurement object by irradiating the measurement object with light in a straight line and receiving the reflected light of the irradiation light and calculating the coordinate point of the received reflected light. A method of obtaining a deviation amount of a shape measuring instrument for obtaining a deviation amount with respect to a measurement object,
A first plane portion defining a z-axis whose normal direction is one coordinate axis and an intersection line of a plane on which the first plane portion is formed define an x-axis which is a coordinate axis orthogonal to the z-axis. Two plane portions, and a third plane portion and a fourth plane portion that form intersecting lines on a plane that is orthogonal to the z-axis and that is different from the plane on which the first plane portion is formed, With respect to a reference workpiece defining a coordinate system serving as a reference by the z-axis, the x-axis, and the y-axis that is a coordinate axis orthogonal to both the z-axis and the x-axis, the first plane portion, the second An irradiation step of irradiating light in a straight line so as to pass through the plane portion, the third plane portion, and the fourth plane portion;
Point cloud data for obtaining point cloud data of the irradiation point of the light irradiated on the reference workpiece in the coordinate system defined in the shape measuring instrument by information obtained from the reflected light of the light irradiated on the reference workpiece in the irradiation step. An acquisition step;
Based on the point cloud data obtained in the point cloud data obtaining step, a deviation amount calculating step for calculating a deviation amount of the coordinate system defined in the shape measuring instrument with respect to the reference coordinate system;
A method for obtaining a deviation amount of a shape measuring instrument, comprising: In the shape measuring instrument shift amount acquisition method according to claim 1,
The method for obtaining a deviation amount of a shape measuring instrument, wherein the intersecting line is parallel to the y-axis. In the shape amount measuring device displacement acquisition method according to claim 1 or 2,
The deviation amount calculating step includes:
From the point cloud data acquired in the point cloud data acquisition step, the first plane part, the second plane part, the third plane part, and the fourth plane part in the coordinate system defined in the shape measuring instrument A straight line calculating step for calculating a straight line equation indicating a cutting line of light applied to any two or more plane portions;
And a deviation amount calculating step of calculating the deviation amount based on an equation of two or more straight lines calculated in the straight line calculating step. In the shape measuring instrument deviation amount acquisition method according to claim 3,
When the shift amount is a shift angle θx around the x axis of the coordinate system defined in the shape measuring instrument with respect to the reference coordinate system,
In the straight line calculation step, from the point group data of the irradiation point in the first plane part, the point group data of the irradiation point in the third plane part, and the point group data of the irradiation point in the fourth plane part, the shape measuring instrument The equation of the first straight line showing the cutting line of the light irradiated on the first plane part in the coordinate system defined in the above, the equation of the third straight line showing the cutting line of the light irradiated on the third plane part, and the fourth Calculate the equation of the fourth straight line showing the cutting line of the light irradiated to the plane part,
In the displacement amount calculating step, the displacement angle θx is calculated based on the calculated equation of the first straight line, the equation of the third straight line, and the equation of the fourth straight line. Deviation amount acquisition method. In the deviation amount acquisition method according to claim 3 or 4,
When the deviation amount is a deviation angle θz around the z-axis of the coordinate system defined in the shape measuring instrument with respect to the reference coordinate system,
In the straight line calculation step, from the point group data of the irradiation point in the first plane part and the point group data of the irradiation point in the second plane part, to the first plane part in the coordinate system defined in the shape measuring instrument Calculate a first straight line equation indicating the cutting line of the irradiated light and a second straight line equation indicating the cutting line of the light irradiated to the second plane part,
In the deviation amount calculating step, the deviation angle θz is calculated based on the calculated equation of the first straight line and the equation of the second straight line. In the deviation measuring method of the shape measuring instrument according to any one of claims 3 to 5,
When the deviation amount is the deviation position Δy in the y-axis direction of the coordinate system defined in the shape measuring instrument with respect to the reference coordinate system,
In the straight line calculation step, from the point group data of the irradiation point in the first plane part and the point group data of the irradiation point in the second plane part, to the first plane part in the coordinate system defined in the shape measuring instrument Calculate a first straight line equation indicating the cutting line of the irradiated light and a second straight line equation indicating the cutting line of the light irradiated to the second plane part,
In the deviation amount calculating step, the deviation position Δy is calculated based on the calculated equation of the first straight line and the equation of the second straight line. In the deviation amount acquisition method of the shape measuring instrument according to any one of claims 3 to 6,
When the deviation amount is a deviation angle θy around the y axis of the coordinate system defined in the shape measuring instrument with respect to the reference coordinate system,
In the straight line calculation step, from the point group data of the irradiation point in the first plane part, the point group data of the irradiation point in the third plane part, and the point group data of the irradiation point in the fourth plane part, the shape measuring instrument The equation of the first straight line showing the cutting line of the light irradiated on the first plane part in the coordinate system defined in the above, the equation of the third straight line showing the cutting line of the light irradiated on the third plane part, and the fourth Calculate the equation of the fourth straight line showing the cutting line of the light irradiated to the plane part,
In the displacement amount calculating step, the displacement angle θy is calculated based on the calculated equation of the first straight line, the equation of the third straight line, and the equation of the fourth straight line. Deviation amount acquisition method. In the deviation amount acquisition method of the shape measuring instrument according to any one of claims 3 to 7,
When the shift amount is the shift position Δx in the x-axis direction of the coordinate system defined in the shape measuring instrument with respect to the reference coordinate system,
In the straight line calculation step, from the point group data of the irradiation point in the third plane part and the point group data of the irradiation point in the fourth plane part, to the third plane part in the coordinate system defined in the shape measuring instrument Calculate the equation of the third straight line indicating the cutting line of the irradiated light and the equation of the fourth straight line indicating the cutting line of the light irradiated to the fourth plane part,
In the deviation amount calculating step, the deviation position Δx is calculated based on the calculated equation of the third straight line and the equation of the fourth straight line. In the deviation amount acquisition method of the shape measuring instrument according to any one of claims 3 to 8,
When the deviation amount is the deviation position Δz in the z-axis direction of the coordinate system defined in the shape measuring instrument with respect to the reference coordinate system,
In the straight line calculation step, from the point group data of the irradiation point in the third plane part and the point group data of the irradiation point in the fourth plane part, to the third plane part in the coordinate system defined in the shape measuring instrument Calculate the equation of the third straight line indicating the cutting line of the irradiated light and the equation of the fourth straight line indicating the cutting line of the light irradiated to the fourth plane part,
In the deviation amount calculating step, the deviation position Δz is calculated based on the calculated equation of the third straight line and the equation of the fourth straight line.   A program for causing a computer to execute the deviation amount acquisition method according to any one of claims 1 to 9.   A computer-readable recording medium storing the program according to claim 10. A shape measuring instrument that measures the three-dimensional shape of a measurement object by irradiating the measurement object with light in a straight line and receiving the reflected light of the irradiation light and calculating the coordinate point of the received reflected light. A reference work for obtaining a deviation amount used when obtaining a deviation amount,
A first plane portion defining a z-axis whose normal direction is one coordinate axis and a cross line between the plane on which the first plane portion is formed and an x-axis defining a coordinate axis orthogonal to the z-axis And having two plane portions and a third plane portion and a fourth plane portion that form a line of intersection on a plane orthogonal to the z-axis and different from the plane on which the first plane portion is formed. Characteristic reference work for obtaining deviation. In the reference | standard workpiece for deviation | shift amount acquisition of Claim 12,
A reference workpiece for obtaining a deviation amount, wherein the intersecting line is parallel to the y-axis.

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