JP7180163B2 - Roundness measuring device - Google Patents

Description

The present invention relates to a roundness measuring device for measuring the roundness of the inner peripheral surface of a segment ring.

In the shield construction method, an excavation process and a segment assembly process are alternately repeated. In the excavation process, the shield machine is moved forward by taking a reaction force from the existing segment ring while excavating the natural ground with the shield machine. In the segment assembly process, after excavation by the shield machine, a new segment ring is assembled in front of the existing segment ring by an erector.

In splicing a new segment ring in front of the existing segment ring, it is necessary to assemble the new segment ring while keeping the segment ring perfectly circular with high accuracy. For this purpose, it is necessary to measure the roundness of the segment ring, and a technique for measuring the roundness is disclosed in, for example, Patent Document 1. According to the description of Patent Document 1, an annular frame is attached to a frame at the rear of the shield machine, a non-contact ranging sensor is attached to the frame, and the distance from the ranging sensor to the segment ring is measured. Measured by a distance sensor.

Japanese Patent No. 4682168

However, in the technique described in Patent Document 1, the annular frame interferes with segment assembly work and the like.

SUMMARY OF THE INVENTION Accordingly, it is an object of the present invention to provide a roundness measuring apparatus that does not interfere with work.

In order to solve the above problems, a roundness measuring device for measuring the roundness of the inner peripheral surface of a segment ring installed behind a shield machine that excavates the ground and constructs a tunnel is the segment ring A three-dimensional measuring device for measuring the three-dimensional coordinates of each point on the inner peripheral surface of the segment ring, and from the three-dimensional coordinates of each point measured by the three-dimensional measuring device, the roundness of the inner peripheral surface of the segment ring is determined. a computing computer;

According to the above, the three-dimensional coordinates of each point on the inner peripheral surface of the segment ring are measured by a three-dimensional measuring instrument, and the roundness of the inner peripheral surface of the segment ring is calculated from the three-dimensional coordinates of each measured point. , the three-dimensional measuring instrument and computer can be installed with a high degree of freedom, and the three-dimensional measuring instrument and computer do not interfere with work.

There are a plurality of the three -dimensional measuring instruments, and at least one of them is installed so that the X-axis, Y-axis, or Z-axis of the coordinate system is parallel to the axis of the tunnel, and the three-dimensional measuring instrument is positioned within the segment ring. an acquisition process in which the three-dimensional coordinates of each point on the surface of the obstacle are measured, and the computer acquires the three-dimensional coordinates of each point measured by each of the three-dimensional measuring instruments for each of the three-dimensional measuring instruments; , a synthesizing process for synthesizing the point groups for each of the three-dimensional measuring instruments as a set of points for each of the three-dimensional measuring instruments, the three-dimensional coordinates of which are acquired by the acquiring process; and the points synthesized by the synthesizing process. a first extraction process for extracting a point group on the inner peripheral surface of the segment ring from the group; a second extraction process for extracting a set of points existing on the surface of the inner circumference as a point group of the inner circumference circle; Based on the center point identification process for calculating the three-dimensional coordinates of the center point of the inner circumference circle, and the three-dimensional coordinates of each point of the point group of the inner circumference circle and the three-dimensional coordinates of the center point of the inner circumference circle, a radius calculation process for calculating the radius of the inner circumference circle for each circumferential position of the inner circumference circle; and a radius calculated by the radius calculation process and the segment ring for each circumferential position of the inner circumference circle and a roundness calculation process of calculating a difference from the design radius and using the difference as the roundness of the inner peripheral surface of the segment ring.

According to the above, even if the three-dimensional coordinates of each point cannot be measured over the entire circumference of the inner peripheral surface of the segment ring with one three-dimensional measuring instrument, the inner circumference of the segment ring can be measured by using a plurality of three-dimensional measuring instruments. The three-dimensional coordinates of each point can be measured over the entire circumference of the surface.
Since point groups for each three-dimensional measuring instrument are combined by combining processing, the coordinate system of each point group can be unified.
Since the point group of the inner peripheral surface of the segment is extracted by the first extraction process, the roundness of the inner peripheral surface of the segment ring can be accurately measured without being affected by obstacles.
Since the point group of the inner peripheral circle is extracted by the second extraction process, the processing load on the computer can be reduced.

The first extraction process includes a joint point group extraction process of extracting a point group of joints that are joints of the segment rings from the point group synthesized by the synthesis process by a feature extraction process, and a process of extracting a set of points near the joint point group extracted by the joint point group extraction process from the obtained point group as a point group of the inner peripheral surface of the segment ring.

According to the above, since the point group of the joint which is the joint of the segment ring is used, the extracted point group accurately expresses the inner peripheral surface of the segment.

The first extraction process calculates an average value of each component of the three-dimensional coordinates of each point of the point group synthesized by the synthesis process, thereby specifying the center axis of the inner peripheral surface of the segment ring. From the point group synthesized by the axis specifying process and the synthesizing process, a set of points whose distance from the central axis specified by the central axis specifying process is equal to or greater than a predetermined threshold value is selected from the inner peripheral surface of the segment ring. and a process of extracting as a point group.

According to the above, the central axis of the inner peripheral surface of the segment ring is specified by the average value of each component of the three-dimensional coordinates of each point of the point group synthesized by the synthesizing process, and the distance from the central axis is determined by the predetermined threshold. Since the set of points that is greater than or equal to the value is extracted, the set of extracted points accurately represents the inner peripheral surface of the segment.

The three-dimensional measuring device measures the color information of each point on the inner peripheral surface of the segment ring and on the surface of the obstacle in the segment ring, and the first extraction processing is synthesized by the synthesis processing. a process of referring to the color information of each point of the point group and extracting a set of points whose color information has a predetermined color as the point group of the inner peripheral surface of the segment ring.

Since the inner peripheral surface of the segment has a different color from that of the obstacle, the point cloud extracted by the above processing accurately expresses the inner peripheral surface of the segment.

The three-dimensional measuring instrument is installed so that the X-axis, Y-axis or Z-axis of the coordinate system is parallel to the axis of the tunnel, and measures three-dimensional data of each point on the surface of the obstacle within the segment ring. Acquisition processing in which coordinates are measured and the computer acquires the three-dimensional coordinates of each point measured by the three-dimensional measuring instrument, and a point group as a set of points for which the three-dimensional coordinates are acquired by the acquisition processing a first extraction process for extracting a point group of the inner peripheral surface of the segment ring from the point group of the inner peripheral surface of the segment ring extracted by the first extraction process; A second extraction process for extracting a set of points existing on the surface as a point group of the inner circumference circle, and from the three-dimensional coordinates of each point of the point group of the inner circumference circle extracted by the second extraction process Based on the center point identification process for calculating the three-dimensional coordinates of the center point of the inner circumference circle, and the three-dimensional coordinates of each point of the point group of the inner circumference circle and the three-dimensional coordinates of the center point of the inner circumference circle, a radius calculation process for calculating the radius of the inner circumference circle for each circumferential position of the inner circumference circle; and a radius calculated by the radius calculation process and the segment ring for each circumferential position of the inner circumference circle and a roundness calculation process of calculating a difference from the design radius and using the difference as the roundness of the inner peripheral surface of the segment ring.

According to the above, since the point group of the inner peripheral surface of the segment is extracted by the first extraction process, it is possible to accurately measure the roundness of the inner peripheral surface of the segment ring without being affected by obstacles. .
Since the point group of the inner peripheral circle is extracted by the second extraction process, the processing load on the computer can be reduced.

The center point identifying process connects the nearest points of the point group of the inner circumference circle extracted by the second extraction process with a line to generate a closed curve composed of these lines, and the center of gravity of the closed curve. as the three-dimensional coordinates of the center point of the inner circumference circle.

According to the above, it is possible to accurately calculate the three-dimensional coordinates of the center point of the inner peripheral circle.

The center point characteristic processing calculates the average value of each component of the three-dimensional coordinates of each point of the point group of the inner circumference circle extracted by the second extraction processing as each of the three-dimensional coordinates of the center point of the inner circumference circle. Includes processing to calculate as a component.

According to the above, it is possible to accurately calculate the three-dimensional coordinates of the center point of the inner peripheral circle.

The center point identifying process obtains an approximate circle from the three-dimensional coordinates of each point of the point group of the inner circumference circle extracted by the second extraction process, and determines the three-dimensional coordinates of the center point of the approximate circle to the inner circle. It is calculated as the three-dimensional coordinates of the center point of the circumference.

According to the above, it is possible to accurately calculate the three-dimensional coordinates of the center point of the inner peripheral circle.

According to the present invention, it is possible to provide a roundness measuring device that does not interfere with work.

It is the figure which showed the shield machine used for tunnel construction work. It is a block diagram of a roundness measuring device. FIG. 4 is a drawing showing a point group composed of points whose three-dimensional coordinates and color information are measured by a reference three-dimensional measuring instrument; FIG. 3 is a drawing showing a point cloud composed of points whose 3D coordinates and color information are measured by an accompanying 3D measuring device; FIG. 5 is a drawing showing a combined point group obtained by combining the point groups shown in FIGS. 3 and 4; FIG. It is drawing which showed the synthesized point group and the point group of the inner peripheral circle included in it. It is drawing which showed the point cloud of an inner peripheral circle. It is drawing which showed the point group of an inner peripheral circle, and a closed curve.

Hereinafter, embodiments of the present invention will be described with reference to the drawings. However, although various technically preferable limitations are attached to the embodiments described below in order to carry out the present invention, the scope of the present invention is not limited to the following embodiments and illustrated examples.

1. Shield Machine and Segment Ring FIG. 1 is a diagram showing a shield machine 10 for excavating natural ground. The skin plate 11 constitutes the outer shell of the shield machine 10 . Skin plate 11 is reinforced by ring girder 12 . A rotating cutter 13 is provided at the tip of the skin plate 11 . Inside the skin plate 11, a cutter drive mechanism 14, a shield jack 15, a work platform 16, a soil unloading device 17, an erector 18, and the like are provided. A work platform 16 protrudes rearward, and a holding device 25 is attached to the work platform 16. - 特許庁The existing segment ring 20 is held in a perfect circle by the holding device 25 .

In the tunnel construction work, the excavation process of the shield machine 10 and the assembly process of the segment ring 20 are alternately repeated.
During excavation of the shield machine 10, when the rotary cutter 13 is rotationally driven by the cutter drive mechanism 14, the natural ground is excavated. Earth and sand generated by excavation is stored in the chamber 19 and discharged from the chamber 19 by the earth removing device 17 . During excavation of the natural ground, the shield machine 10 obtains propulsion force by extending the shield jack 15 while pressing the shield jack 15 against the constructed segment ring 20 to take reaction force from the segment ring 20.例文帳に追加
After excavating the shield machine 10, the shield jack 15 is contracted. Then, a new segment ring 20 is assembled by assembling the segments in a ring shape in front of the existing segment ring 20 by the erector 18 .

As described above, the excavation process of the shield machine 10 and the assembly process of the segment rings 20 are alternately and repeatedly performed to arrange the segment rings 20 in the axial direction of the tunnel. A joint 21 that serves as a joint between the adjacent segment rings 20 is formed on the inner peripheral surface of the arrangement of the segment rings 20 . The shape of the joint 21 is circular, and the circle is perpendicular to the axial direction of the tunnel.

A roundness measuring device 30 shown in FIG. 2 is used to measure the roundness of these segment rings 20, especially the segment rings 20 near the face during the tunnel construction work as described above.

2. Roundness Measuring Device FIG. 2 is a block diagram of the roundness measuring device 30 .

The roundness measuring device 30 includes a computer 31, a display device 32, an input device 33, a storage section 34, a plurality of three-dimensional measuring instruments 35, and the like.
The computer 31 has a CPU, GPU, ROM, RAM, system bus, hardware interface, and the like.
The display device 32 is, for example, a liquid crystal display device, an organic EL display device, or a projector. The computer 31 generates a video signal through arithmetic processing and outputs the video signal to the display device 32 . Then, a screen according to the video signal is displayed on the display device 32 . The display device 32 and the computer 31 may be integrated or separate.
The input device 33 is, for example, a switch, keyboard or pointing device or a combination thereof. The input device 33 may be a touch panel provided on the surface of the display device 32 . When operated, the input device 33 outputs a signal to the computer 31 according to the content of the operation.

The storage unit 34 is a storage device such as a semiconductor memory or a hard disk drive. The storage unit 34 may be built in the computer 31 or may be externally attached to the computer 31 . The storage unit 34 stores a program 40 readable and executable by the computer 31 . The functions and arithmetic processing of the computer 31 are implemented by the program 40 .

The three-dimensional measuring device 35 measures the three-dimensional coordinates and color information of many points on the surface of the object to be measured without contact. The three-dimensional coordinates of each point measured by the three-dimensional measuring device 35 are represented by an orthogonal coordinate system defined by mutually orthogonal X-, Y-, and Z-axes. That is, the three-dimensional coordinates of each point measured by the three-dimensional measuring device 35 consist of X, Y and Z coordinates. The color information of each point measured by the three-dimensional measuring device 35 consists of R value, G value and B value. Note that the color space of the color information may be HSV or HLS, for example, other than RGB.

The three-dimensional measuring device 35 includes an infrared irradiator that irradiates an object to be measured with infrared rays, a distance image camera (depth image camera) or a three-dimensional laser scanner, a color image camera, and a distance image camera or a three-dimensional laser scanner. and a microcomputer for converting the output signal and the output signal of the color image camera into three-dimensional coordinates and color information of each point by signal processing. However, the three-dimensional measuring instrument 35 does not have a microcomputer or the like, and the output signal of the three-dimensional measuring instrument 35 is processed by the computer 31, so that the computer 31 outputs the output signal of the three-dimensional measuring instrument 35 to the three-dimensional It may be converted into original coordinates and color information.

Here, the distance image camera measures the distance from the distance image camera to each point on the surface of the object to be measured, and the value of each pixel of the image obtained by imaging with the distance image camera represents the distance. The distance measurement method of the range image camera may be a TOF (Time of Flight) method or a light coding method.

The three-dimensional measuring instrument 35 does not have a color image camera, the color information of each point on the surface of the object to be measured is not measured by the three-dimensional measuring instrument 35, and the three-dimensional coordinates of each point are may be measured.

As shown in FIG. 1, the three-dimensional measuring device 35 is installed at the rear portion of the work platform 16 while facing the inner peripheral surface of the front segment ring 20 near the face. The measurement ranges of each three-dimensional measuring device 35 partially overlap each other. When the installation position and orientation of the three-dimensional measuring instrument 35 are determined, the position of the origin of the orthogonal coordinate system and the orientation of each axis are determined. It is installed so that the Z-axis is parallel to the axis of the tunnel. One three-dimensional measuring instrument 35 installed so that the X-axis, Y-axis or Z-axis is parallel to the axis of the tunnel is called a reference three-dimensional measuring instrument 35A, and the other three-dimensional measuring instruments 35 are attached. It is called a three-dimensional measuring device 35B. In the following description, it is assumed that the Z-axis of the coordinate system of the reference three-dimensional measuring device 35A is parallel to the axis of the tunnel, the X-axis is horizontal, and the Y-axis is vertical.

Since the three-dimensional measuring device 35 is directed toward the inner peripheral surface of the segment ring 20 in front of the face near the face, the three-dimensional coordinates and color information of many points on the inner peripheral surface of these segment rings 20 are obtained by the three-dimensional measuring device. Measured by 35. The measurement range of each three-dimensional measuring device 35 also includes various devices such as the work platform 16, the erector 18, the earth removing device 17, and the holding fixture 25. Hereinafter, among the measurement objects included in the measurement range of each three-dimensional measuring device 35, objects other than the segment ring 20 are referred to as obstacles. The color of the inner peripheral surface of the segment ring 20 is gray, but the color of obstacles such as the work platform 16 is often other than gray.

Since a plurality of three-dimensional measuring instruments 35 are installed as described above, these three-dimensional measuring instruments 35 can measure the inner peripheral surface of the segment ring 20 over the entire circumferential direction.

1, the three-dimensional measuring device 35 may be installed on the ring girder 12 in a direction away from the face. Also, the three-dimensional measuring device 35 may be installed on the holding device 25 .

3. Processing Executed by Computer The program 40 causes the computer 31 to execute processing described below, and the computer 31 calculates the roundness of the segment ring 20 . Prior to processing according to the program 40 , the operator installs the three-dimensional measuring device 35 and connects the three-dimensional measuring device 35 to the computer 31 .

(1) Measurement Processing/Acquisition Processing First, the computer 31 controls each three-dimensional measuring device 35 so that each three-dimensional measuring device 35 measures the inner peripheral surface of the segment ring 20 and the surface of the obstacle. Then, each three-dimensional measuring device 35 transfers the measurement results to the computer 31, and the computer 31 obtains the three-dimensional coordinates and color information of each point on the inner peripheral surface of the segment ring 20 and the surface of the obstacle. Get every 35. Here, the process of converting the measurement result of each three-dimensional measuring device 35 into three-dimensional coordinates and color information as described above may be performed by the microcomputer of each three-dimensional measuring device 35 or by the computer 31. good.

The set of three-dimensional coordinates and color information acquired by the computer 31 includes not only the three-dimensional coordinates and color information of each point on the inner peripheral surface of the segment ring 20, but also points on the surface of the obstacle. Also, since the computer 31 acquires a set of three-dimensional coordinates and color information of each point for each three-dimensional measuring device 35, the number of sets is equal to the number of three-dimensional measuring devices 35. FIG.

Hereinafter, a set of points whose three-dimensional coordinates and color information are measured by the three-dimensional measuring device 35 will be referred to as a point cloud. Also, the point group measured by the reference three-dimensional measuring device 35A is called a reference point group, and the point group measured by the auxiliary three-dimensional measuring device 35B is called an accompanying point group. 3 shows an example of the reference point group 91, and FIG. 4 shows an example of the associated point group 92. As shown in FIG. In FIGS. 3 and 4, each point on the inner peripheral surface of the segment ring 20 is illustrated and each point on the surface of the obstacle is omitted. includes not only points on the inner peripheral surface of the segment ring 20 but also points on the surface of the obstacle.

(2) Synthesis processing The computer 31 expresses the coordinates of each point of the reference point group 91 and the coordinates of each point of the associated point group 92 in a common coordinate system, thereby synthesizing the associated point group 92 with the reference point group 91. do. Specifically, when the computer 31 executes the following feature amount calculation processing, matching processing, and coordinate conversion processing, the attached point group 92 is combined with the reference point group 91 .

First, the computer 31 calculates feature amounts for the reference point group 91 . Similarly, the computer 31 calculates feature amounts for the associated point cloud 92 .
Next, based on the feature amount of the reference point group 91 and the feature amount of the associated point group 92, the computer 31 calculates the point of the reference point group 91 and the associated point group representing the three-dimensional coordinates and color information of the same point to be measured. Match 92 points.
Next, the computer 31 obtains a coordinate transformation matrix from the X, Y, and Z coordinates of the matched points, and converts the coordinates of each point of the attached point group 92 to the coordinates of the reference point group 91 based on the coordinate transformation matrix. Convert to system.
As a result, the attached point group 92 and the reference point group 91 are expressed in a common coordinate system, and the attached point group 92 is combined with the reference point group 91 to generate the point group 93 as shown in FIG. When there are three or more three-dimensional measuring instruments 35, there are a plurality of associated point groups 92, so the computer 31 synthesizes the remaining associated point groups 92 into the reference point group 91 in the same manner. In FIG. 5, illustration of the point cloud on the surface of the obstacle is omitted. A surface point cloud is also included.

The computer 31 then filters the composite point cloud 93 to remove noise.

By synthesizing the point groups for each three-dimensional measuring device 35 by the above synthesizing process, the coordinate system of each point group can be unified with the coordinate system of the reference point group 91 .

(3) Processing for Extracting Point Cloud of Segment Inner Peripheral Surface Next, the computer 31 extracts a point group of the inner peripheral surface of the segment ring 20 from the synthesized point cloud 93 . As a result, the influence of obstacles inside the segment ring 20 can be reduced.
The processing for extracting the point group of the inner peripheral surface of the segment ring 20 from the synthesized point group 93 is, for example, any of the following (3-1) to (3-3). Note that the following (3-3) is applicable when the color of the obstacle is other than gray.

(3-1)
First, the computer 31 extracts the point group 94 of the joint 21 from the composite point group 93 by performing feature extraction processing.
Next, the computer 31 extracts points approximated to the XY coordinates of each point of the point group 94 of the joint 21 from the synthesized point group 93 . Specifically, using the XY coordinates of each point of the combined point group 93 and the XY coordinates of each point of the point group 94 of the joint 21, each point of the combined point group 93 is converted to each point of the joint 21 point group 94 Find the distance to a point. Then, the computer 31 extracts points where the obtained distance is equal to or less than a predetermined threshold value. A set of extracted points is the point group of the inner peripheral surface of the segment ring 20 .
Since the point group 94 of the joint 21 is used as described above, the extracted point group accurately expresses the inner peripheral surface of the segment ring 20 .

(3-2)
First, the computer 31 calculates the average value of the X coordinate, the average value of the Y coordinate, and the average value of the Z coordinate of each point of the combined point group 93 . The average value of the X coordinates and the average value of the Y coordinates represent the temporary position of the central axis of the inner peripheral surface of the segment ring 20 .
Next, the computer 31 uses the XY coordinates of each point of the synthesized point cloud 93 and the XY coordinates of the temporary position of the central axis of the inner peripheral surface of the segment ring 20 to segment from each point of the synthesized point cloud 93. A distance to the temporary position of the central axis of the inner peripheral surface of the ring 20 is obtained. Then, the computer 31 extracts points where the obtained distance is equal to or greater than a predetermined threshold value. Since the predetermined threshold value is a value slightly smaller than the design radius of the inner peripheral surface of the segment ring 20 , the set of extracted points is the point group of the inner peripheral surface of the segment ring 20 .
Since a set of points whose distance from the central axis of the inner peripheral surface of the segment ring 20 is equal to or greater than a predetermined threshold value is extracted, the extracted set of points accurately represents the inner peripheral surface of the segment ring 20 .

(3-3)
First, the computer 31 refers to the color information of each point in the combined point group 93 and extracts points whose color information is gray. Since the color of the inner peripheral surface of the segment ring 20 is gray, the set of extracted points is the point group of the inner peripheral surface of the segment ring 20 .
The point cloud extracted as described above accurately expresses the inner peripheral surface of the segment.

(4) Extraction processing of point group on the inner peripheral circle of the segment ring Next, as shown in FIG. Extract the points that exist in . Specifically, the computer 31 designates a predetermined value and extracts points having the predetermined Z coordinate from the point group 95 on the inner peripheral surface of the segment ring 20 . As shown in FIGS. 6 and 7, a set 96 of these points is the point group of the inner peripheral circle of the segment ring 20. FIG.

The predetermined value is, for example, the average value of the Z coordinates of the points of the point group 94 of the adjacent joints 21 and calculated by the computer 31 . That is, the computer 31 performs feature extraction processing to extract the point group 94 of the adjacent joints 21 from the combined point group 93 and calculates the average value of the coordinates of each point of the point group 94 .

Similarly, the computer 31 extracts the point group 96 of the inner circumference existing on another XY plane. The processing described below is performed for each point group 96 of the inner circumferential circle existing on the common XY plane.

Since the point group 96 of the inner circumference circle is extracted as described above, the number of points is reduced, and the subsequent processing load is reduced.

(5) Identifying the center point of the inner circumference circle Next, the computer 31 determines the center point of the inner circumference circle based on the XYZ coordinates of each point of the point group 96 of the inner circumference circle existing on the common XY plane. Calculate 97 XYZ coordinates. For example, any one of the following (5-1) to (5-3) is applicable, and in any of the following (5-1) to (5-3), the Z coordinate of the center point 97 is the inner peripheral circle is equal to the Z coordinate of each point in the point cloud 96 of . This is because the Z coordinates of the points of the point group 96 of the inner circumferential circle existing on the common XY plane are equal to each other.

(5-1)
First, as shown in FIG. 8, the computer 31 generates a closed curve 98 consisting of these lines by connecting each point of the point group 96 on the inner circumference with a line to the nearest point. The computer 31 then calculates the XYZ coordinates of the center of gravity of the closed curve 98 . The calculated XYZ coordinates are the XYZ coordinates of the center point 97 of the inner circumference circle. Through such processing, the XYZ coordinates of the center point 97 of the inner peripheral circle can be accurately calculated.

(5-2)
The computer 31 calculates the average value of the X coordinates, the average value of the Y coordinates, and the average value of the Z coordinates of each point of the point group 96 on the inner circumference circle. The calculated average value of the X coordinates is the X coordinate of the center point 97 of the inner circumference circle, the calculated average value of the Y coordinates is the Y coordinate of the center point 97 of the inner circumference circle, and the calculated average value of the Z coordinates is It is the Z coordinate of the center point 97 of the inner peripheral circle. Through such processing, the XYZ coordinates of the center point 97 of the inner peripheral circle can be accurately calculated.

(5-3)
The computer 31 obtains an approximate circle (especially its equation) from the XYZ coordinates of each point of the point group 96 of the inner circumference circle by regression analysis such as the least squares method. Then, the computer 31 obtains the XYZ coordinates of the center point of the approximate circle. The XYZ coordinates of the center point of the approximate circle are the XYZ coordinates of the center point 97 of the inner circumference circle. Through such processing, the XYZ coordinates of the center point 97 of the inner peripheral circle can be accurately calculated.

(6) Radius calculation Next, the computer 31 calculates the inner circumference circle for each position in the circumferential direction of the inner circumference circle based on the XYZ coordinates of each point of the point group 96 of the inner circumference circle and the XYZ coordinates of the center point 97 . Calculate the radius of For example, it is calculated by the following method (6-1) or (6-2).

(6-1)
The computer 31 calculates the distance to the center point 97 for each point of the point group 96 on the inner circumference circle according to the formula for the distance between two points. The calculated distance is the radius of the inner circumference circle.

(6-2)
First, the computer 31 extracts several points near the top of the inner circumference circle (points in area A shown in FIG. 7) from the point group 96 of the inner circumference circle. Next, the computer 31 obtains an approximate straight line (particularly its equation) from the XYZ coordinates of these points by regression analysis such as the method of least squares. Next, the computer 31 calculates the distance from the approximate straight line to the center point 97 according to the point-straight distance formula. The calculated distance is the radius of the inner circumference circle.

Similar processing is performed for each of the regions B to H shown in FIG. Here, region B represents the range near the bottom of the inner circumference circle, region C represents the range near one side of the inner circumference circle, and region D represents the range near the other side of the inner circumference circle. . Area E is between area A and area C, area F is between area B and area D, area G is between area D and area A, area H is between area C and area B. be. The regions A, F, C, H, B, E, D, and G are arranged in this order in the circumferential direction at a pitch of 45°.

(7) Roundness Calculation Process Next, the computer 31 calculates the difference between the radius calculated in the process (6) and the design value for each circumferential position of the inner circumference circle. The calculated difference is the roundness. The design value is the design radius of the inner peripheral surface of the segment ring 20 . The design values are stored in the storage unit 34 in advance, incorporated in the program 40 in advance, or input by the user using the input device 33 .

(8) Result Recording/Output Processing Next, the computer 31 records the calculated roundness in the storage unit 34 . Also, the computer 31 causes the display device 32 to display the circularity as a numerical value. When the computer 31 is connected to another computer via a network, the computer 31 may transmit the circularity to the other computer, and the circularity may be stored and managed by the other computer.

4. Advantageous Effect The three-dimensional coordinates of each point on the inner peripheral surface of the segment ring 20 are measured by the three-dimensional measuring device 35, and the roundness of the inner peripheral surface of the segment ring 20 is calculated from the three-dimensional coordinates of each measured point. Since the calculation is performed by the computer 31, the roundness measuring device 30 can be provided on a small scale. In addition, the three-dimensional measuring device 35 and the computer 31 can be installed with a high degree of freedom, and the three-dimensional measuring device 35 and the computer 31 do not interfere with work.

Even if a worker accidentally touches the auxiliary three-dimensional measuring device 35B and the auxiliary three-dimensional measuring device 35 is displaced, the roundness can be measured. This is for converting the coordinate system of the auxiliary three-dimensional measuring device 35B into the coordinate system of the reference three-dimensional measuring device 35A.

Since the point group 96 of the inner circumference circle is extracted for each XY plane, the roundness of the inner circumference circle can be measured in a plurality of vertical cross sections. For example, if the roundness of the inner circumference circle is measured at the vertical cross section closest to the face, the roundness is the measured value at the stage immediately after assembly, and the roundness of the inner circumference circle at the vertical cross section second closest to the face. If the roundness is measured, the roundness is the measured value immediately after the tail of the shield machine 10 passes through. Roundness is a measured value at the stage immediately after injection of the back-filling material.

5. Modifications Although the embodiments for carrying out the present invention have been described above, the above-described embodiments are for facilitating understanding of the present invention, and are not intended to limit and interpret the present invention. In addition, the present invention can be modified and improved without departing from its spirit, and the present invention also includes equivalents thereof. Below, changes from the above embodiment will be described. The modifications described below may be applied in combination wherever possible.

(1) In the above embodiment, a plurality of three-dimensional measuring instruments 35 are used. On the other hand, if a single three-dimensional measuring instrument 35 can measure the three-dimensional coordinates and color information of the entire inner peripheral surface of the segment ring 20 in the circumferential direction, one three-dimensional measuring instrument 35 may be used. In this case, the three-dimensional measuring device 35 is installed so that the X-axis, Y-axis or Z-axis of the coordinate system is parallel to the axis of the tunnel, and the three-dimensional measuring device 35 is the reference three-dimensional measuring device. 35A. In addition, the processing of the computer 31 is changed from the above-mentioned “(1) measurement processing/acquisition processing” to “(3) extraction processing of the point group of the inner peripheral surface of the segment” by omitting “(2) synthesis processing”. Transition. Then, in "(3) point group extraction processing on the inner peripheral surface of the segment" and "(4) point group extraction processing on the inner peripheral circle of the segment ring", the reference point group 91 is used instead of the synthetic point group 93. used. In other words, the “composite point cloud 93” in the descriptions of “(3) extraction processing of the point cloud on the inner peripheral surface of the segment” and “(4) extraction processing of the point cloud on the inner peripheral circle of the segment ring” is replaced with “reference point cloud 91”.

(2) In the above embodiment, the Z-axis of the coordinate system of the reference three-dimensional measuring device 35A was parallel to the axis of the tunnel, but this need not be the case. In this case, a target parallel to the axis of the tunnel is placed within the segment ring 20, and the three-dimensional coordinates and color information of each point on the target are measured by the three-dimensional measuring instrument 35. Then, the computer 31 calculates a coordinate transformation matrix from the XYZ coordinates of each point of the target included in the synthesized point cloud 93, and transforms the synthesized point cloud 93 into a coordinate system in which the Z axis is parallel to the axis of the tunnel. Coordinate transformation by matrix.

DESCRIPTION OF SYMBOLS 10... Shield machine 20... Segment ring 21... Joint 30... Roundness measuring device 31... Computer 35... Three-dimensional measuring instrument 91... Reference point group 92... Associated point group 93... Composite point group 94... Joint point group 95... Point group of inner peripheral surface of segment ring 96 Point group of inner peripheral circle 97 Center point of inner peripheral circle 98 Closed curve

Claims (8)

A roundness measuring device for measuring the roundness of the inner peripheral surface of a segment ring installed behind a shield machine that excavates the ground and constructs a tunnel,
a three-dimensional measuring instrument for measuring the three-dimensional coordinates of each point on the inner peripheral surface of the segment ring;
a computer that calculates the roundness of the inner peripheral surface of the segment ring from the three-dimensional coordinates of each point measured by the three-dimensional measuring device;
There are a plurality of the three-dimensional measuring instruments , and at least one is installed so that the X-axis, Y-axis, or Z-axis of the coordinate system is parallel to the axis of the tunnel,
the three-dimensional measuring device measures the three-dimensional coordinates of each point on the surface of the obstacle within the segment ring;
the computer
Acquisition processing for acquiring the three-dimensional coordinates of each point measured by each of the three-dimensional measuring instruments for each of the three-dimensional measuring instruments;
a synthesizing process of synthesizing the point groups of each of the three-dimensional measuring instruments as a set of points of each of the three-dimensional measuring instruments, the three-dimensional coordinates of which are acquired by the acquiring process;
a first extraction process for extracting a point group of the inner peripheral surface of the segment ring from the point group synthesized by the synthesis process;
A second method for extracting a set of points existing on a plane perpendicular to the axis of the tunnel as a point group of an inner circumference circle from the point group of the inner circumference surface of the segment ring extracted by the first extraction process. an extraction process;
A center point identification process for calculating the three-dimensional coordinates of the center point of the inner circumference circle from the three-dimensional coordinates of each point of the point group of the inner circumference circle extracted by the second extraction process;
calculating the radius of the inner circumference circle for each position in the circumferential direction of the inner circumference circle based on the three-dimensional coordinates of each point of the point group of the inner circumference circle and the three-dimensional coordinates of the center point of the inner circumference circle; Radius calculation processing;
A difference between the radius calculated by the radius calculation process and the design radius of the segment ring is calculated for each position in the circumferential direction of the inner peripheral circle, and the difference is taken as the roundness of the inner peripheral surface of the segment ring. and a roundness measuring device for executing a roundness calculation process. The first extraction process includes
a joint point group extraction process for extracting a point group of joints that are joints of the segment rings from the point group synthesized by the synthesis process by a feature extraction process;
extracting , from the point group synthesized by the synthesis process, a set of points in the vicinity of the joint point group extracted by the joint point group extraction process as a point group of the inner peripheral surface of the segment ring. Item 2. The roundness measuring device according to item 1 . The first extraction process includes
central axis identification processing for identifying the central axis of the inner peripheral surface of the segment ring by calculating the average value of each component of the three-dimensional coordinates of each point of the point group synthesized by the synthesis processing;
A set of points whose distance from the central axis specified by the central axis specifying process is equal to or greater than a predetermined threshold value is extracted from the point group synthesized by the synthesizing process as a point group of the inner peripheral surface of the segment ring. The roundness measuring device according to claim 1 , comprising: The three-dimensional measuring device measures color information of each point on the inner peripheral surface of the segment ring and on the surface of the obstacle in the segment ring,
The first extraction process refers to the color information of each point of the point group synthesized by the synthesis process, and sets a set of points whose color information has a predetermined color as a point group of the inner peripheral surface of the segment ring. 3. The roundness measuring device according to claim 1 , further comprising a process of extracting. A roundness measuring device for measuring the roundness of the inner peripheral surface of a segment ring installed behind a shield machine that excavates the ground and constructs a tunnel,
a three-dimensional measuring instrument for measuring the three-dimensional coordinates of each point on the inner peripheral surface of the segment ring;
a computer that calculates the roundness of the inner peripheral surface of the segment ring from the three-dimensional coordinates of each point measured by the three-dimensional measuring device;
The three-dimensional measuring instrument is installed so that the X-axis, Y-axis or Z-axis of the coordinate system is parallel to the axis of the tunnel, and measures three-dimensional data of each point on the surface of the obstacle within the segment ring. measure the coordinates,
the computer
Acquisition processing for acquiring the three-dimensional coordinates of each point measured by the three-dimensional measuring device;
a first extraction process for extracting a point group of the inner peripheral surface of the segment ring from a point group as a set of points whose three-dimensional coordinates are acquired by the acquisition process;
A second extraction process for extracting a set of points existing on a plane perpendicular to the axis of the tunnel as a point group of an inner peripheral circle from the point group of the inner peripheral surface of the segment ring extracted by the first extraction process. an extraction process;
A center point identification process for calculating the three-dimensional coordinates of the center point of the inner circumference circle from the three-dimensional coordinates of each point of the point group of the inner circumference circle extracted by the second extraction process;
calculating the radius of the inner circumference circle for each position in the circumferential direction of the inner circumference circle based on the three-dimensional coordinates of each point of the point group of the inner circumference circle and the three-dimensional coordinates of the center point of the inner circumference circle; Radius calculation processing;
A difference between the radius calculated by the radius calculation process and the design radius of the segment ring is calculated for each position in the circumferential direction of the inner peripheral circle, and the difference is taken as the roundness of the inner peripheral surface of the segment ring. and a roundness measuring device for executing a roundness calculation process. The center point identification process is
A closed curve composed of these lines is generated by connecting the nearest neighbors of each point of the point group of the inner circumference circle extracted by the second extraction process with a line, and the three-dimensional coordinates of the center of gravity of the closed curve are The roundness measuring device according to any one of claims 1 to 5, further comprising a process of calculating the three-dimensional coordinates of the center point of the circumference. The center point identification process is
A process of calculating an average value of each component of the three-dimensional coordinates of each point of the point group of the inner circumference circle extracted by the second extraction process as each component of the three-dimensional coordinates of the center point of the inner circumference circle. The roundness measuring device according to any one of claims 1 to 5 . The center point identification process is
An approximate circle is obtained from the three-dimensional coordinates of each point of the point group of the inner circumference circle extracted by the second extraction process, and the three-dimensional coordinates of the center point of the approximate circle The roundness measuring device according to any one of claims 1 to 5, which is calculated as original coordinates.

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