JP6309938B2 - 3D position measurement system, 3D position measurement probe, and calibrator - Google Patents

Description

  The present invention relates to a three-dimensional position measurement system, a three-dimensional position measurement probe, and a calibrator.

  Recently, a three-dimensional position measurement system that measures the position of a specific point of a probe (a position in a three-dimensional coordinate) in an imaging target space (image-capable space) in which a plurality of cameras are installed has been developed. For example, in a motion capter device, in a space to be imaged formed by a plurality of cameras, the infrared (light) emitted from the cameras is reflected by a spherical reflection marker attached to a human joint or the like and reflected. An image is taken with a camera. Based on at least two pieces of imaging data, the position of the reflective marker on the three-dimensional coordinates is measured by the principle of triangulation. A technique related to the motion captor is described in, for example, Japanese Patent Application Laid-Open No. 2014-211404. The three-dimensional position measurement system is a system that measures (measures) the position of a specific point of a probe on a three-dimensional coordinate according to the same principle as that of a motion captor device.

  The current three-dimensional position measurement system is, for example, a camera set in which two cameras are always fixed at a predetermined distance, a probe provided with a plurality of reflective markers, and two cameras. And an arithmetic unit that calculates the position of a specific point of the probe based on the triangulation principle based on the imaging data of the reflection marker. The arithmetic device is mainly composed of a computer and measurement software installed in the computer. The probe is a handy probe and is configured to be carried by the user. This three-dimensional position measurement system is used, for example, for measuring / inspecting the dimensions of each part of an industrial product (such as an automobile or its parts). As a technique relating to such a three-dimensional coordinate measurement, for example, it is described in Japanese Patent Application Publication No. 2013-528795 and Japanese Patent Application Laid-Open No. 2015-125641.

Japanese Patent Application Laid-Open No. 2014-211404 Special table 2013-528795 gazette JP2015-125641A

  In the above three-dimensional position measurement system, since the distance between the two cameras is constant and the two cameras use a camera set that images in a certain direction, position measurement and Calibration can be performed relatively easily and with high accuracy.

  However, in this three-dimensional position measurement system, since the two camera positions and orientations are fixed, it is difficult to form a free imaging target space. Therefore, the inventor has conceived that the imaging target space can be formed more freely by using a plurality of cameras that can be installed independently, such as a motion captor device. And the inventor came up with a new problem based on such an idea.

  Specifically, in the above-described three-dimensional position measurement system, when a specific position (for example, the position of each part of an industrial product) is measured from all directions by the probe in an imaging target space formed by a plurality of freely arranged cameras, The accuracy decreases depending on the imaging direction of the camera. This is probably because the probe is configured on the premise of the camera configuration of the camera set. Infrared reflection imaging data is not stable. On the other hand, there are spherical reflective markers that can reflect in all directions, but spherical reflective markers require advanced technology for true sphere processing, and have problems in terms of manufacturing accuracy and cost. . From the viewpoint of position measurement accuracy, the spherical shape error of the reflective marker can be a displacement of position measurement.

  The present invention has been made in view of such circumstances, and even in a system in which the positions of a plurality of cameras can be changed, the position on a three-dimensional coordinate of a specific part can be obtained by a probe that can be easily manufactured. It is an object of the present invention to provide a three-dimensional position measurement system capable of accurately measuring the three-dimensional position measurement probe and a three-dimensional position measurement probe and calibrator used therefor.

  The three-dimensional position measurement system of the present invention includes a plurality of cameras capable of infrared irradiation, a base, a plurality of reflective markers provided on the base, a probe having a position specifying unit provided on the base, and the plurality of In the three-dimensional position measurement system comprising: an arithmetic unit that calculates the position of the position specifying unit in three-dimensional coordinates based on the triangulation principle based on imaging data regarding the plurality of reflective markers acquired from the camera, the base unit Comprises a first surface, a cylindrical portion projecting cylindrically from the first surface, and a reflection suppression region formed around at least the cylindrical portion of the first surface, and the reflective marker Is arranged on the protruding end surface so as to cover the protruding end surface of the cylindrical part.

  According to the present invention, since the reflective marker is arranged at a position protruding from the first surface, even if the reflective marker is arranged in a direction deviated from the front in the imaging direction (infrared irradiation direction) of the camera, In addition to better reflecting the irradiation, a clearer contour between the reflection marker and the reflection suppression region can be provided to the arithmetic unit. Thereby, even when the relative positions of a plurality of cameras can be changed, the calculation device can calculate the position of the reflective marker with high accuracy, and by extension, can accurately measure the position on the three-dimensional coordinate of the position specifying unit of the probe. can do. Moreover, since it is a structure provided with a cylindrical part and the reflective marker which covers the said end surface as a probe, an advanced processing technique is not required for the manufacture, and a probe can be manufactured simply and accurately.

It is a block diagram which shows the structure of the three-dimensional position measurement system of this embodiment. It is a block diagram which shows the structure of the probe of this embodiment. It is sectional drawing for demonstrating the structure of the probe of this embodiment. It is a block diagram which shows the structure of a convex-shaped calibrator. It is a block diagram which shows the structure of a spherical calibrator. It is explanatory drawing which shows the measurement result of the spherical calibrator in Experimental example 1. FIG. It is explanatory drawing which shows the measurement result of the convex calibrator in Experimental example 1. FIG. It is a block diagram which shows the structure of the spherical probe in Experimental example 2. It is explanatory drawing for demonstrating the Y-axis rotation in Experimental example 2. FIG. It is explanatory drawing for demonstrating the X-axis rotation in Experimental example 2. FIG. It is explanatory drawing which shows the measurement result of the Y-axis rotation of the spherical probe in Experimental example 2. It is explanatory drawing which shows the measurement result of the Y-axis rotation of the probe 2 in Experimental example 2. FIG. It is explanatory drawing which shows the measurement result of the X-axis rotation of the spherical probe in Experimental example 2. It is explanatory drawing which shows the measurement result of the X-axis rotation of the probe 2 in Experimental example 2. FIG. It is explanatory drawing which shows the measurement result of the Y-axis rotation of the probe which has a concave target in Experimental example 2. FIG. It is explanatory drawing which shows the measurement result of the X-axis rotation of the probe which has a concave target in Experimental example 2. FIG.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. However, the drawings are conceptual diagrams for explanation, and dimensions and the like are not strict. In particular, in FIG. 3, the probe 2 is greatly extended in the vertical direction (thickness direction).

  As shown in FIG. 1, the three-dimensional position measurement system A of the present embodiment includes a plurality of cameras 1, probes 2, and an arithmetic device 3. Since the camera 1 and the arithmetic device 3 are known devices, detailed description thereof is omitted. The camera 1 includes an imaging unit 11 that captures an image and an irradiation unit 12 that irradiates infrared rays. The camera 1 is a camera sensor or an optical camera, for example. The camera 1 is fixed to a wall surface (ceiling etc.) of a room, for example. Each camera 1 may be a stand type (for example, a tripod type) that can be moved independently. An imaging target space S is formed by the plurality of cameras 1.

  The probe 2 is a unit for transmitting a signal to be measured, and provides data (information) about its own position to the arithmetic device 3 by being imaged by the camera 1. The probe 2 is a handy type probe that the user can carry with one hand in the imaging target space S. The probe 2 is a three-dimensional position measurement probe.

  Specifically, as shown in FIGS. 2 and 3, the probe 2 includes a base portion 21, a plurality of reflection markers 22 provided on the base portion 21, and a position specifying portion 23 provided on the base portion 21. The base portion 21 is a prismatic member (for example, a resin member) as a whole, and includes a first surface 21a, a prismatic portion 211, a plurality of columnar portions 212, a reflection suppressing region 213, and a pin-shaped portion 214. And a rod-shaped part 215. The first surface 21 a is one surface of the prismatic part 211. The shape of the prismatic part 211 is arbitrary. As an example, the prismatic portion 211 of the present embodiment is formed in a pentagonal prism shape (planar view is a pentagonal shape). The first surface 21a is one of the pentagonal surfaces. The probe 2 is provided with a grip portion (not shown) for the user to hold on the opposite side of the first surface 21a, for example.

  The cylindrical part 212 is a part protruding in a cylindrical shape from the first surface 21 a of the prismatic part 211. The protruding length (height) of the cylindrical portion 212 from the first surface 21a is set to 1 mm. This protruding length is preferably 0.5 mm to 1.5 mm. When measuring the position of the reflective marker 22, the measuring instrument can be easily positioned by abutting (engaging) the measuring instrument and the side surface of the cylindrical part 212, and the position of the cylindrical part 212 can be determined more accurately. It can be measured. Therefore, a protruding amount is required such that a measuring instrument (for example, a rod-shaped instrument) is caught (engaged) with the side surface of the cylindrical portion 212. From the viewpoint of ease of this position measurement operation, the protruding length of the cylindrical portion 212 is preferably 0.5 mm or more. Then, as the protruding length of the cylindrical part 212 increases, the possibility of overlapping with the other cylindrical part 212 increases when imaging is performed from an oblique direction. From the viewpoint of machining accuracy, it is difficult to maintain the columnar machining accuracy as the protrusion length increases. From these viewpoints, the protruding length of the cylindrical portion 212 is preferably 1.5 mm or less. The cylindrical part 212 may be formed integrally with the prismatic part 211 as in the present embodiment, and a through hole (or female screw hole) is provided in the prismatic part 211 and is fitted (screwed) there. It may be a separate cylindrical member.

  Five cylindrical portions 212 are formed on the first surface 21a. The five cylindrical portions 212 are arranged so that their trajectories are substantially V-shaped (or substantially U-shaped) so that the arithmetic device 3 can recognize the orientation of the probe 2. Note that the two cylindrical portions 212 other than the three outermost shells (three points forming the maximum triangle) allow the arithmetic unit 3 to recognize the orientation and inclination of the probe 2 in the three-dimensional space. They are provided for the purpose and are arranged unevenly.

  The reflection suppression region 213 is formed around at least the cylindrical portion 212 of the first surface 21a. In the present embodiment, the reflection suppression region 213 is formed on the entire first surface 21a. The reflection suppression region 213 is a region in which a black color paint is applied to the first surface 21a (or formed of a black color member) in order to suppress infrared reflection. The black color means a color that hardly reflects infrared rays (light) such as black or dark blue. That is, in this embodiment, the 1st surface 21a including the circumference | surroundings of the cylindrical site | part 212 is a black color.

  The pin-shaped portion 214 is a pin-shaped portion (for example, a convex shape, a convex arc shape, a cylindrical shape, or a conical shape) that protrudes through the reflective marker 22 from the center of the protruding end surface 212a of the cylindrical portion 212. The pin-shaped portion 214 of the present embodiment is a columnar member that is separate from the base portion 21. A concave portion 212b is formed in the cylindrical portion 212 at the center position of the projecting end surface 212a having a circular shape. The pin-shaped part 214 is detachably fitted (press-fitted here) to the recess 212b. That is, the pin-shaped part 214 is detachably fixed to the recess 212b. The protruding length (height) of the pin-shaped portion 214 from the protruding end surface 212a is set to about 5 mm. Further, the radius of the pin-shaped portion 214 is about 1.5 mm. The pin-shaped part 214 is removable and is removed after the reflection marker 22 is arranged, and is operated so as not to exist on the probe 2 at the time of position measurement. Note that the pin-shaped portion 214 may be formed integrally with the columnar portion 212.

  The rod-shaped portion 215 is a rod-shaped portion protruding from the side surface of the prismatic portion 211 (the side surface corresponding to one vertex of the first surface 21a). The tip of the rod-shaped part 215 is formed in a convex arc shape (for example, a spherical shape). The tip of the rod-shaped part 215 may be conical or pyramidal.

  The reflective marker 22 is for reflecting infrared rays, and is disposed on the protruding end surface 212a so as to cover the protruding end surface 212a of the cylindrical portion 212. That is, each of the five reflection markers 22 is disposed on the corresponding cylindrical portion 212. The reflection marker 22 is at least an exposed portion formed in a white color. The reflective marker 22 is formed in a circular shape that matches the shape of the protruding end surface 212a. The reflective marker 22 and the protruding end surface 212a are perfect circles, and are formed to have the same diameter (for example, a radius of 10 to 30 mm) in this embodiment. The reflective marker 22 of the present embodiment is a circular sheet-like seal having a white-colored surface and a back surface that can be bonded, and having a through hole 22a formed in the center. The surface of the reflective marker 22 (white color) is formed of a known reflective material, for example, a glass-based material (or paint). In addition, a through hole 22 a through which the pin-like portion 214 is inserted is formed at the center position of the reflective marker 22. That is, the reflection marker 22 can be said to be a donut-shaped (annular) seal. The reflective marker 22 and the protruding end surface 212a are bonded and fixed in a state where the pin-shaped portion 214 is inserted into the through hole 22a. As described above, one cylindrical portion 212 and one reflective marker 22 form one convex target T. That is, the probe 2 of the present embodiment has five convex targets T.

  The position specifying part 23 is set at the tip (protruding end) of the rod-shaped part 215. In other words, the tip of the rod-shaped part 215 is the position specifying part 23. The position specifying unit 23 is a target for measuring a three-dimensional position by the arithmetic device 3, and is set to an arbitrary part of the probe 2. The user contacts the position specifying unit 23 with a position where the measurement target (for example, industrial product) B is to be measured, and the arithmetic device 3 measures the position of the position specifying unit 23 so that the position of the measurement target B is measured. can do.

  The arithmetic device 3 calculates the position of the position specifying unit 23 in the three-dimensional coordinates (X, Y, Z) based on the triangulation principle based on the imaging data regarding the plurality of reflection markers 22 acquired from the plurality of cameras 1. Device. Specifically, the arithmetic device 3 includes a computer 31 having a CPU, a memory, and the like, and measurement software 32 that operates on the computer 31. As the measurement software 32, for example, commercially available software (software related to three-dimensional position measurement and motion capture) can be used. The computer 31 is communicably connected to all the cameras 1.

  The computing device 3 computes the contour (contour line) on the image (on the pixel) of the reflective marker 22 from the imaging data received from the camera 1. The contour is determined based on the black and white border. The computing device 3 computes the center of gravity (center) position of the contour shape from the computed contour shape. The calculation device 3 recognizes the calculated barycentric position as the position of the reflection marker 22. The arithmetic unit 3 is set to measure a three-dimensional position on the assumption that the center position of the reflective marker 22 is recognized as the position of the reflective marker 22. For example, in the imaging data received from one camera 1, when the contour is circular, the center of the circle is the position of the reflection marker 22, and thus the arithmetic device 3 determines the center position (two-dimensional coordinates) of the contour. Is calculated. For example, when the outline is elliptical, the computing device 3 computes the position of the center of gravity (two-dimensional coordinates) from the ratio of the ellipse and sets it as the position of the reflective marker 22. The outline is determined based on, for example, pixels in which black and white coexist. That is, the clearer the contour, the more accurately the position of the reflective marker 22 is measured.

  The arithmetic device 3 calculates the three-dimensional coordinates of the reflection marker 22 based on the triangulation principle based on the imaging data of two or more cameras 1. For example, the arithmetic device 3 can calculate the (X, Y,...) Of the reflection marker 22 based on the position data of the reflection marker 22 on the (X, Y) coordinates and the position data of the reflection marker 22 on the (Y, Z) coordinates. Z) Calculate the position on the coordinates. The arithmetic device 3 calculates the three-dimensional coordinates of all the reflection markers 22, grasps the position and orientation of the probe 2 therefrom, and calculates the position of the position specifying unit 23 on the three-dimensional coordinates. The positional relationship between the reflection marker 22 and the position specifying unit 23 in the probe 2 is measured in advance and stored (set) in the arithmetic device 3. The positional relationship is preferably measured, for example, with a highly accurate three-dimensional measuring device (for example, a three-dimensional laser scanner). It can be said that the calculation device 3 includes a contour calculation unit and a gravity center calculation unit as functions.

(Experimental example 1)
Here, the measurement accuracy of the pitch between two points of the convex calibrator (corresponding to a “calibrator”) 8 having the target T (projection length 1 mm) and the spherical calibrator 9 having a spherical target of the present embodiment. Compare in terms of The pitch between two points is obtained by measuring the three-dimensional coordinates of two target points and calculating the distance from the coordinates. As shown in FIG. 4, the convex calibrator 8 is provided with three targets T <b> 1, T <b> 2, and T <b> 3 that are separated from each other on one surface of a rectangular parallelepiped portion 81. The target T1 is disposed at one end of the region 81, the target T2 is disposed at the other end of the region 81, and the target T3 is not located at an intermediate point on the straight line connecting the target T1 and the target T2 (near the target T1). Has been placed.

  As shown in FIG. 5, the spherical calibrator 9 is provided with targets P1, P2, and P3 spaced apart from each other in a bar-shaped portion 91. The targets P <b> 1 to P <b> 3 are configured by installing a spherical reflective marker 93 at the tip of a rod-shaped part 92 protruding in the same direction (orthogonal direction) from the part 91. The target P1 is disposed at one end of the region 91, the target T2 is disposed at the other end of the region 91, and the target P3 is not located at an intermediate point on the straight line connecting the target P1 and the target P2 (closer to the target P1). Has been placed. A separation distance t (a pitch between two points) between the target T1 and the target T2 and a separation distance p between the target P1 and the target P2 are the same (or substantially the same). Separately, the actual size (true value) of the separation distances t and p measured by the measuring device was 499.94 mm.

  In the same three-dimensional position measurement system as described above, the separation distances t and p were measured in two directions at which the calibrators 8 and 9 were rotated (Y-axis rotation). The orientation is 0 ° position (positions where the targets T1, P1 are on the right side and targets T2, P2 are on the left side when viewed from the predetermined front), and 180 ° positions (the targets T1, P1 are on the left side when viewed from the predetermined front). The positions where the targets T2 and P2 are on the right side). In the measurement space (imaging target space S), the calibrators 8 and 9 were fixed by hand and sampled at intervals of 30 seconds.

  As shown in FIGS. 6 and 7, the measurement result of the convex calibrator 8 (FIG. 7) is smaller than the measurement result of the spherical calibrator 9 (FIG. 6) in the separation distance p at the 0 ° position and the 180 ° position. Differences in measurement values, variation, and deviation from true values are small. The difference from the true value was 0.07 mm for the spherical calibrator 9 and 0.03 mm for the convex calibrator 8. The variation was 0.2 mm for the spherical calibrator 9 and 0.04 mm for the convex calibrator 8. The difference in volume accuracy was 0.15 mm for the spherical calibrator 9 and 0.02 mm for the convex calibrator 8. Further, in the measurement result of the convex calibrator 8, spike noise that appeared in the measurement result of the spherical calibrator 9 did not appear. Thus, it has been found that the convex calibrator 8 having the target T of this embodiment is more advantageous in three-dimensional position measurement than the spherical calibrator 9 having a spherical target. In particular, even when the measurement is performed by hand, the convex calibrator 8 has small variations in measurement values of the calibrator, so that the accuracy of camera calibration is improved, and as a result, the position of the position specifying unit 23 can be measured with high accuracy. .

(Experimental example 2)
In Experimental Example 2, the probe 2 of this embodiment and the spherical probe 7 were compared. As shown in FIG. 8, the spherical probe 7 includes a rod-like portion 71, four targets 72, and a position specifying portion 73. The target 72 includes a rod-shaped branch portion 721 and a spherical reflective marker 722 disposed at the tip of the rod-shaped branch portion 721. In Experimental Example 2, as shown in FIGS. 9 and 10, the probes 2 and 7 are positioned in a state where the position specifying parts 23 and 73 are positioned with respect to a predetermined camera front (centering on the position specifying parts 23 and 73). Is rotated around the Y axis (rotated in the direction 1 → 2 → 3 in FIG. 9), and separately rotated around the X axis (rotated in the direction 1 → 2 in FIG. 10). And position measurement. The Y-axis rotation means horizontal swing (left-right swing) with respect to the camera lens, and the X-axis rotation means vertical swing (back-and-forth swing) with respect to the camera lens. Specifically, in the experiment of the Y-axis rotation, sampling is performed 10 times in the first direction (1 in FIG. 9), sampling is performed 10 times in the second direction (2 in FIG. 9) rotated 45 ° from the first direction, Sampling was performed 10 times in the third direction (3 in FIG. 9) rotated 45 ° from the second direction. In the experiment of X-axis rotation, sampling was performed 30 times continuously while moving from horizontal (upward) to vertical (frontward) (while rotating from 1 to 2 in FIG. 10).

  As shown in FIGS. 11 and 12, it was found that the measurement result of the probe 2 (FIG. 12) has less variation in the Y-axis rotation than the measurement result of the spherical probe 7 (FIG. 11). Similarly, as shown in FIGS. 13 and 14, the measurement result of the probe 2 (FIG. 14) was found to have less variation in the X-axis rotation than the measurement result of the spherical probe 7 (FIG. 13). . That is, the position measurement accuracy can be maintained high even if the orientation of the probe 2 changes. As shown in FIGS. 15 and 16, when the probe 2 is compared with a probe having a plurality of concave targets on a flat base, the measurement result of the probe 2 having the convex target T (FIGS. 12 and 12). 14) It is understood that the position measurement accuracy is superior to the measurement results (FIGS. 15 and 16) of the probe having the concave target. Any unevenness of the target enables contact with the measuring instrument, and improves the position accuracy (measurement accuracy) of the target in the probe. As described above, in the probe 2 having the target T, even when the orientation is deviated from the front of the camera, the contour of the reflective marker 22 is accurately read, and the position measurement accuracy of the central coordinates of the reflective marker 22 analyzed by the computer is high. .

(Function and effect)
According to the present embodiment, even when the reflective marker 22 does not face the front (a position that looks circular) with respect to the camera 1, that is, even when the reflective marker 22 is imaged obliquely, the reflective marker 22 is Since it is a position that protrudes from one surface 21a and the periphery thereof is a part that suppresses reflection (black color part), the camera 1 can more clearly capture the outline (for example, elliptical shape) of the reflective marker 22. . Therefore, even when the arrangement (distance between cameras, etc.) and orientations of the plurality of cameras 1 are freely set within a range where the reflective marker 22 can be imaged (assumed work range), the position of the reflective marker 22 is detected with high accuracy. As a result, the position of the position specifying unit 23 can be measured with high accuracy. Specifically, by using the probe 2, the arithmetic device 3 can more accurately determine the contour of the reflective marker 22 based on the imaging data of the camera 1, thereby accurately determining the center of gravity of the contour, that is, the center position of the reflective marker 22. It can measure well. Then, the calculation device 3 calculates the three-dimensional coordinates of the reflection markers 22 based on the positions of the plurality of reflection markers 22 calculated with high precision, and the three-dimensional coordinates of the position specifying unit 23 from the three-dimensional coordinates of the plurality of reflection markers 22. Measure coordinates. Therefore, according to this embodiment, the position on the three-dimensional coordinate of the position specifying unit 23 can be measured with higher accuracy.

  Moreover, according to this embodiment, since there exists the said effect | action, the precision of the calibration using the probe 2 and the some camera 1 is also improved. When the distance between the two cameras 1 is always physically fixed, the position of the camera 1 can be accurately defined in advance in the arithmetic device 3. Therefore, in this case, the accuracy of calibration is maintained even with the conventional probe 2 configuration. However, the space to be imaged by a plurality of cameras that can be independently installed (the space to be imaged S can be changed), such as a stationary camera that is installed on a fixed object such as a wall or a camera that is fixed to a movable stand. When S is formed, the distance between the cameras cannot be set in advance, and it is difficult to maintain calibration accuracy. According to the present embodiment, even in such a case, the arithmetic device 3 can recognize the contour of the reflective marker 22 with high accuracy, so that the calibration accuracy can be maintained with high accuracy. For example, the calibration of the present embodiment is performed by the arithmetic device 3 based on the imaging data obtained by imaging the probe 2 with the two cameras 1.

  In addition, according to the present embodiment, the cylindrical portion 212 and the circular reflection marker 22 may be manufactured, and advanced technology (for example, forming the reflection marker 22 into a true sphere) is not necessary for manufacturing. In order to improve accuracy, it is required to improve the processing accuracy of the sphere. According to the present embodiment, the measurement accuracy can be improved with the simple probe 2. And since it is a simple shape, the probe 2 can be formed more accurately. Thereby, the accuracy of position measurement is also improved. In addition, in the case of the conventional spherical reflective marker, it is often arranged in the air, and its periphery is imaged whitish, and the clarity of the boundary may decrease. According to this embodiment, since the periphery of the reflection marker 22 is the reflection suppression region 213, the clarity of the boundary is ensured. The accuracy of determining the contour is lowered when the black-and-white boundary is blurred or missing. According to the present embodiment, the black-and-white boundary is clearer than the conventional probe.

  Further, according to the present embodiment, since the base portion 21 has the pin-shaped portion 214 and the reflective marker 22 has the through-hole 22a, when placing the reflective marker 22 (seal) on the protruding end surface 212a and bonding it, an operator The reflective marker 22 may be disposed so that the pin-shaped portion 214 passes through the through hole 22a. Thereby, the center of the projecting end face 212a and the center of the reflective marker 22 automatically coincide with each other, and the operator can easily and accurately install the reflective marker 22 coaxially with the cylindrical portion 212. That is, according to this embodiment, the workability of the work of fixing the reflective marker 22 can be improved. And since the pin-shaped site | part 214 is located in the center of the protrusion end surface 212a and the reflective marker 22, the influence on the reading (clarity) of the outline of the reflective marker 22 is suppressed. Even if the center portion of the reflection marker 22 is blurred in the imaging data, the outline reading is not affected. That is, according to the present embodiment, workability can be improved while maintaining position measurement accuracy.

  Further, according to the present embodiment, the pin-shaped portion 214 can be removed from the recess 212b after the arrangement of the reflective marker 22 is completed. By removing the pin-shaped part 214 before starting the position measurement, it is easy for the operator to work, and it is possible to eliminate the possibility that the pin-shaped part 214 obstructs the reflection of the reflection marker 22 by any chance. That is, according to the present embodiment, it is possible to more reliably eliminate the influence on the reading of the boundary. As described above, even if the concave portion 212b is exposed by removing the pin-shaped portion 214, it is the central portion of the reflective marker 22, so that there is no effect on the reading of the contour (that is, the reading of the position of the target T). .

(Other)
The present invention is not limited to the above embodiment. For example, the shape of the base portion 21 is not limited to the above, and it is sufficient that the first surface 21a is formed. For example, the base portion 21 may have a polygonal plate shape or a disk shape. Moreover, the pin-shaped part 214, the recessed part 212b, and the through-hole 22a are not necessary. The reflective marker 22 may be formed on the protruding end surface 212a. For example, the reflective marker 22 may be formed by applying (arranging) a white-colored material (a reflective material or the like) to the protruding end surface 212a. However, by using the seal-like reflective marker 22, the operator can easily and accurately perform the pasting operation. Moreover, it is preferable that five or more targets T are formed from the viewpoint of detecting the orientation of the probe 2. Further, the pin-shaped portion 214 may be formed in a white color. Further, the pin-shaped portion 214 may be formed with a trough so that it can be removed at the root portion or the intermediate portion of the pin-shaped portion 214 after the reflection marker 22 is attached.

1: camera, 2: probe, 21: base, 21a: first surface,
212: cylindrical portion, 212a: protruding end surface, 213: reflection suppression region,
214: Pin-shaped part, 215: Bar-shaped part, 212b: Recessed part,
22: Reflective marker, 22a: Through hole, 8: Convex calibrator,
23: Position specifying unit, A: Three-dimensional position measurement system, S: Space to be imaged

Claims (8)

Multiple cameras capable of infrared irradiation,
A probe having a base, a plurality of reflective markers provided on the base, and a position specifying part provided on the base;
An arithmetic device that calculates the position of the position specifying unit in three-dimensional coordinates according to the principle of triangulation based on imaging data regarding the plurality of reflective markers acquired from the plurality of cameras;
In a three-dimensional position measurement system comprising
The base includes a first surface, a plurality of columnar portions protruding in a columnar shape from the first surface, and a reflection suppressing region formed around at least the columnar portion of the first surface. ,
The three-dimensional position measurement system, wherein the reflective marker is disposed on the protruding end surface so as to cover the protruding end surface of the cylindrical part. The base includes a pin-like portion protruding through the reflective marker from the center of the protruding end surface,
The three-dimensional position measurement system according to claim 1, wherein a through-hole through which the pin-like portion is inserted is formed at the center of the reflective marker.   3. The three-dimensional position measurement system according to claim 2, wherein the reflective marker is a circular sheet-like seal having a white-colored surface and a back surface that is an adhesive surface and having the through-holes formed therein. A concave portion is formed in the center of the protruding end surface in the cylindrical portion,
4. The three-dimensional position measurement system according to claim 2, wherein the pin-like portion is separate from the base and is detachably fixed to the recess. 5.   The three-dimensional position measurement system according to claim 1, wherein the plurality of cameras are separate from each other and can be independently installed.   The three-dimensional position measurement system according to any one of claims 1 to 5, wherein a protruding length of the cylindrical portion is 0.5 mm or more and 1.5 mm or less. A base, a plurality of reflective markers provided on the base, and a position specifying unit provided on the base, and based on imaging data regarding the plurality of reflective markers acquired from a plurality of cameras, triangulation According to a principle, a probe for measuring a three-dimensional position used in a three-dimensional position measuring system for calculating the position of the position specifying unit in three-dimensional coordinates,
The base includes a first surface, a plurality of columnar portions protruding in a columnar shape from the first surface, and a reflection suppressing region formed around at least the columnar portion of the first surface. ,
The reflective marker is a three-dimensional position measurement probe arranged on the protruding end surface so as to cover the protruding end surface of the cylindrical portion. Multiple cameras capable of infrared irradiation,
A probe having a plurality of markers and a position specifying unit;
Based on imaging data regarding the plurality of markers acquired from the plurality of cameras, an arithmetic device that calculates the position of the position specifying unit in three-dimensional coordinates according to the principle of triangulation;
A calibrator used for calibration with respect to a three-dimensional position measurement system comprising:
A base, and three or more reflective markers provided on the base,
The base includes a first surface, three or more cylindrical portions projecting in a cylindrical shape from the first surface, and a reflection suppressing region formed around at least the cylindrical portion of the first surface, Have
The reflective marker is a calibrator arranged on the protruding end surface so as to cover the protruding end surface of the cylindrical portion.