JP7118535B2 - Three-dimensional shape measurement method, measurement device, and measurement program - Google Patents

Description

The present invention relates to a three-dimensional shape measuring method, a measuring apparatus, and a measuring program. More specifically, the present invention relates to a technique suitable for use in measuring the three-dimensional shape of the surface of an object and the thickness of the members forming the surface.

As a conventional technique for measuring the three-dimensional shape of the surface of an object using a laser scanner that irradiates a laser beam and receives the reflected light, the scan area is appropriately set according to the three-dimensional shape of the object. When the scanning by the laser scanner for each scan area is repeatedly performed for each scan area and the point cloud data is acquired for each scan area, each scan area is overlapped with each other, and the scan areas are overlapped with each other to obtain a reference point. A plurality of targets for three-dimensional shape measurement are attached to the overlapping portion of the scanning area, and the point cloud data for each scan area are combined with each other via a reference point to acquire the three-dimensional shape data of the target object. (Patent Document 1).

JP 2009-204449 A

However, with conventional three-dimensional shape measurement technology, although it is possible to measure the shape of the surface of an object, it is not possible to measure the shape on the opposite side of the surface or the shape of the interior. The thickness of the constituent members cannot be grasped.

Therefore, the present invention provides a three-dimensional shape measuring method, a measuring device, and a measuring program that can grasp the thickness of the members that make up the surface of the measurement object in addition to grasping the surface shape of the measurement object. intended to

In order to achieve such an object, the three-dimensional shape measuring method of the present invention selects a portion where the wall thickness is actually measured for each section having a different shape based on the reference dimensions of the members forming the surface of the object to be measured. a process of measuring the thickness at at least one of the thickness measurement points and specifying the position of the thickness measurement point; and the thickness measurement of the member constituting the surface of the measurement object. a process of generating a cross-sectional shape of the member based on the reference dimensions at the point ; A process of specifying the position of the cross-sectional shape and calculating the center position of the cross-sectional shape of the member, and the position separated from the surface of the measurement object by the actual thickness value of the member to the internal structure of the member. a process in which the cross section of the internal structure of the member is arranged so that the boundary of the cross section passes through; and a process of comparing the shape of the surface of the object to be measured and the shape of the internal structure of the member to obtain the thickness distribution .

In addition, the three-dimensional shape measuring apparatus of the present invention can measure the thickness of each section having a different shape based on the reference dimensions of the member forming the surface of the object to be measured. Means for actually measuring the thickness at at least one actual measurement location and specifying the position of the actual thickness measurement location; means for generating a cross-sectional shape of the member according to the above; means for calculating the central position of the cross-sectional shape of the member; means for locating a cross-section of the internal structure; and means for creating a shape of the internal structure of the member as a portion through which the cross-section of the internal structure of the member has moved relative to a center position with respect to the cross-sectional shape of the member; means for obtaining a thickness distribution by comparing the shape of the surface of the object to be measured and the shape of the internal structure of the member.

In addition, the three-dimensional shape measurement program of the present invention includes one thickness selected as a portion where the thickness is actually measured for each section having a different shape based on the reference dimensions of the member constituting the surface of the object to be measured. A process of actually measuring the thickness at at least one actual measurement location and specifying the position of the actual thickness measurement location; a process of generating a cross-sectional shape of the member according to the above, and fitting the cross-sectional shape of the member to the surface shape of the measurement object to specify the position of the cross-sectional shape of the member with respect to the surface shape of the measurement object; a process of calculating the central position of the cross-sectional shape of the member; arranging a cross-section of an internal structure; creating a shape of the internal structure of the member as a portion through which the cross-section of the internal structure of the member has moved relative to a center position with respect to the cross-sectional shape of the member; The computer is caused to perform a process of obtaining a thickness distribution by comparing the shape of the surface of the object to be measured and the shape of the internal structure of the member.

Therefore, according to the three-dimensional shape measuring method, the three-dimensional shape measuring device, and the three-dimensional shape measuring program, at least one thickness measurement point selected for each section having a different shape based on the reference dimension The thickness is actually measured at one point, and the position of the actual thickness measurement point is specified, and the cross-sectional shape of the member constituting the surface of the object to be measured is determined based on the reference dimensions at the actual thickness measurement point. After specifying, the shape of the surface of the object to be measured and the shape of the internal structure are compared with the boundary of the internal structure aligned with the position separated by the actual thickness value of the member. In addition to the surface shape of the object to be measured, the thickness distribution of the members forming the surface of the object to be measured can be grasped while making it possible to reduce the thickness data acquisition time .

According to the three-dimensional shape measuring method, the three-dimensional shape measuring apparatus, and the three-dimensional shape measuring program of the present invention, in addition to the surface shape of the object to be measured, the thickness distribution of the members constituting the surface of the object to be measured can be grasped, it is possible to improve the usefulness as a three-dimensional shape measuring method.

1 is a flow chart explaining an example of an embodiment of a three-dimensional shape measuring method according to the present invention. FIG. 2 is a functional block diagram of a three-dimensional shape measuring apparatus realized by a three-dimensional shape measuring program when the three-dimensional shape measuring method of the embodiment is implemented using the program; FIG. 2 is a schematic diagram showing an object to be measured in the present invention; (A) is a schematic diagram showing an example of a tubular member. (B) is a schematic diagram showing an example of a member in which tubular members are connected. FIG. 10 is a schematic diagram illustrating a state in which the tubular portion is curved when the actual machine is in use; FIG. 4 is a schematic diagram for explaining <Method I> for arranging the cross section of the internal structure of the tubular portion; FIG. 4 is a schematic diagram for explaining <Method II> for arranging the cross section of the internal structure of the tubular part. FIG. 10 is a schematic diagram explaining <Method III> for arranging the cross section of the internal structure of the tubular part. FIG. 5 is a schematic diagram for explaining how to create the shape of the internal structure of the tubular portion;

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, the configuration of the present invention will be described in detail based on an example of an embodiment shown in the drawings.

1 to 8 show an embodiment of a three-dimensional shape measuring method, a three-dimensional shape measuring apparatus, and a three-dimensional shape measuring program according to the present invention.

The three-dimensional shape measurement method of the present embodiment is based on the reference dimensions of the member that constitutes the surface of the object to be measured. is generated (S4), and the shape of the surface of the object to be measured and the cross-sectional shape of the member (particularly, the portion of the external shape corresponding to the shape of the surface of the object to be measured) are fitted. A process of specifying the position of the cross-sectional shape of the member with respect to the surface shape of the measurement object and calculating the center position of the cross-sectional shape of the member (S5), and actually measuring the thickness of the member from the surface of the measurement object. A process (S6) of arranging the cross section of the internal structure of the member so that the boundary of the cross section of the internal structure of the member passes through the position separated by the value (S6); A process (S7) for creating the shape of the internal structure of the member as a portion that has been moved and passed in association with the center position regarding the shape, and comparing the shape of the surface of the measurement object and the shape of the internal structure of the member. (See FIG. 1).

Here, a single tubular (i.e., hollow) member (see FIG. 3A) is used as a measurement target (referred to as a "measurement target") for three-dimensional shape measurement using the present invention. Alternatively, a member in which a plurality of tubular (that is, hollow) members are arranged such that their longitudinal directions are parallel and these tubular members are connected (see FIG. 3(B)). Specifically, for example, piping in architectural structures such as buildings and mechanical structures such as plants (that is, a single tubular member as shown in FIG. 3A), power generation and garbage incinerators Boiler water wall tubes (that is, a member in which a plurality of tubular members are connected as shown in FIG. 3(B), for example) used for the side wall of a boiler furnace, and the like.

In the description of the present invention, for example, when a single tubular member as shown in FIG. When a member in which a plurality of tubular members are connected as shown in FIG. 3B is the object to be measured, each of the tubular members is called a "tubular portion".

The three-dimensional shape measuring method described above can be implemented by the three-dimensional shape measuring apparatus according to the present invention. The three-dimensional shape measuring apparatus of the present embodiment measures the cross-sectional shape of the member constituting the surface of the object to be measured (especially, the shape corresponding to the outer dimension) based on the reference dimension of the member. and fitting the shape of the surface of the object to be measured and the cross-sectional shape of the member (in particular, the portion of the external shape corresponding to the shape of the surface of the object to be measured) of the object to be measured. Means for specifying the position of the cross-sectional shape of the member with respect to the shape of the surface and calculating the center position of the cross-sectional shape of the member; means for arranging the section of the internal structure of the member so that the boundary of the section of the internal structure of the member passes; It has means for creating the shape of the internal structure of the member as a part, and means for comparing the shape of the surface of the object to be measured and the shape of the internal structure of the member.

The above three-dimensional shape measuring method and three-dimensional shape measuring apparatus can also be implemented and realized by executing a three-dimensional shape measuring program on a computer. Here, a case where a three-dimensional shape measuring program is executed on a computer to implement a three-dimensional shape measuring method and a three-dimensional shape measuring apparatus will be described.

FIG. 2 shows the overall configuration of a computer 10 (which is also the three-dimensional shape measurement apparatus 10 in this embodiment) for executing the three-dimensional shape measurement program 17 of this embodiment.

This computer 10 (three-dimensional shape measuring apparatus 10) includes a control section 11, a storage section 12, an input section 13, a display section 14, and a memory 15, which are connected to each other by a signal line such as a bus.

The control unit 11 controls the entire computer 10 according to a three-dimensional shape measurement program 17 stored in the storage unit 12 and performs calculations related to three-dimensional shape measurement. be.

The storage unit 12 is a device capable of storing at least data and programs, such as a hard disk.

The input unit 13 is an interface (that is, an information input mechanism) for giving at least an operator's command and various information to the control unit 11, and is, for example, a keyboard and a mouse. Note that the input unit 13 may have a plurality of types of interfaces such as both a keyboard and a mouse.

The display unit 14 draws and displays characters, figures, images, etc. under the control of the control unit 11, and is, for example, a display.

The memory 15 serves as a memory space that is a work area when the control unit 11 executes various controls and calculations, and is, for example, RAM (abbreviation for Random Access Memory).

In addition, a signal line such as a bus or a wide area network line is used to enable the computer 10 to transmit and receive signals such as data and control commands (i.e., input and output) to and from the computer 10 as necessary. A data server 20 may be connected. Moreover, the computer 10 may be configured to be able to access a cloud server (not shown) via a network such as the Internet, if necessary.

Then, the control unit 11 of the computer 10 (hereinafter referred to as the "three-dimensional shape measuring apparatus 10") executes a three-dimensional shape measurement program 17 to obtain the three-dimensional shape of the surface of the object to be measured. A data reading unit 11a and a mesh creation unit 11b that perform processing related to the creation of mesh data corresponding to , and the cross-sectional shape of the member (especially, the outer shape in the a cross-sectional shape generation unit 11c that performs processing for generating a shape corresponding to the outer dimension), the shape of the surface of the object to be measured and the cross-sectional shape of the member (particularly, the shape of the object to be measured out of the outer shape) The position of the cross-sectional shape of the member with respect to the surface shape of the object to be measured is specified by fitting the part corresponding to the shape of the surface of the object to be measured, and the center position calculation is performed to calculate the center position of the cross-sectional shape of the member and a process of arranging the section of the internal structure of the member so that the boundary of the section of the internal structure of the member passes through a position separated from the surface of the object to be measured by the actual thickness value of the member. an internal structure cross-section arrangement portion 11e, and an internal structure that performs a process of creating a shape of the internal structure of the member as a portion through which the cross section of the internal structure of the member moves and passes in association with the central position of the cross-sectional shape of the member. A shape creating section 11f and a thickness distribution calculating section 11g for performing a process of comparing the shape of the surface of the object to be measured and the shape of the internal structure of the member are configured.

Then, as a procedure for implementing the three-dimensional shape measuring method, first, point cloud data is prepared (S1).

In the present invention, a point cloud relating to the surface shape of a measurement target as a three-dimensional shape measurement target is used. As the point cloud data used in the present invention, existing data may be used and organized, or newly acquired and organized data may be used.

As the point group data in the present invention, for example, a light irradiation unit having a light source such as a semiconductor laser and a light receiving element such as a CCD (Charge Coupled Device) are provided and arranged apart from each other. Three-dimensional coordinate group/point group data generated using data acquired by measurement performed using a measuring means having a pair of light receiving units configured to construct a stereo camera (in other words, multiple coordinate points in three dimensions) may be used.

A method for creating point cloud data is not limited to a specific method, and an appropriate method is appropriately selected according to the acquired and arranged data (in other words, available data).

For example, as the above measuring means, for example, the triangulation method is used as a measurement principle, and a measurement light such as a laser is irradiated toward the measurement object, and the reflected light reflected by the measurement light on the surface of the measurement object is detected. A non-contact measuring instrument that measures the three-dimensional shape using the data obtained by this (in other words, acquires data on the three-dimensional shape of the surface of the object to be measured) may be used.

In the triangulation method, point cloud data (i.e., object surface coordinate data), and uses the fact that the imaging position varies depending on the distance to the object to geometrically calculate the distance from the imaging position to the object (for example, Toru Yoshizawa, "Latest Optical Three-Dimensional Measurement," Asakura Shoten, 2006).

In addition, a plurality of multi-viewpoint images (in other words, a Multi-viewpoint information) may be stereo-matched to create three-dimensional point cloud data of the object to be measured.

In the present embodiment, the coordinate group data related to the point cloud, which is a set of three-dimensional coordinate values related to the measurement surface of the measurement target, prepared as three-dimensional point cloud data related to the surface shape in the process of S1 is stored in the data file. It is recorded and saved in the storage unit 12 as a point cloud data file 18 .

Next, the thickness is actually measured (S2).

The thickness is used as a reference for specifying the position of the cross section of the internal structure of the tubular portion of the object to be measured with respect to the surface shape in the surface shape data of the measurement result in the process of S6, which will be described later.

Here, in the measurement object, the surface forming the shape on the opposite side of the measurement surface (in other words, the surface facing the measurement surface) and the inner surface viewed from the measurement surface (that is, the photographing/measurement by the measuring means) The surface that cannot be recognized in the original is called the “back surface”.

The number of locations where the wall thickness is actually measured is not limited to a specific number, but is appropriately set to an appropriate number after considering the procedure and method in the processing of S6, which will be described later.

In the actual thickness measurement, the thickness is actually measured and the position coordinates are specified for each location selected and set as the location where the thickness is actually measured (referred to as “measured thickness location”).

The positional coordinates of the actual thickness measurement points are the coordinate system common (in other words, the same) as the coordinate system (specifically, the three-dimensional orthogonal coordinate system) of the point group data/coordinate group data prepared in the processing of S1. , or may be specified as coordinate values in a unique coordinate system and then coordinate values in the coordinate system of the point cloud data/coordinate group data arranged in the processing of S1 A conversion may be performed.

The equipment and methods used to measure wall thickness are not limited to specific equipment or methods. Appropriate ones are appropriately selected from non-contact measuring instruments and methods. Specifically, the actual measurement of the thickness may be performed using an ultrasonic thickness gauge, for example, just as an example.

In the present embodiment, the thickness actually measured in the process of S2 is associated with the coordinates of the positions of the actual thickness measurement points (in other words, the combination of the position coordinates of the actual thickness measurement points and the actual thickness values data) and stored in the storage unit 12 as a wall thickness actual measurement value data file 19 .

Then, as a procedure when the three-dimensional shape measuring program is executed, in other words, as a process in the three-dimensional shape measuring apparatus 10, the coordinate group data relating to the point cloud relating to the measurement surface of the object to be measured is read. .

Specifically, the data reading unit 11a of the control unit 11 reads three-dimensional coordinate group data related to the point cloud related to the measurement surface of the measurement target recorded in the point cloud data file 18 stored in the storage unit 12. Coordinate values are read.

Then, the data reading unit 11a causes the memory 15 to store the coordinate group data relating to the point group regarding the measurement surface of the measurement object.

Next, mesh data of the measurement surface of the object to be measured is created (S3).

In this process, the point cloud data prepared by the process of S1 is converted into surface format data, and mesh data corresponding to the three-dimensional shape of the measurement surface of the object to be measured is created.

A technique for converting point cloud data into surface format data is not limited to a specific conversion method, and an appropriate conversion method may be appropriately selected from conventional or new conversion methods. Specifically, for example, conversion processing may be performed using Delaunay triangulation as a computational principle, and point cloud data may be converted into surface format data.

The mesh data created by the process of S3 is called "measurement result surface shape data". The surface shape data of the measurement result is composed only of information on the shape of the surface of the object to be measured.

In the present embodiment, as processing in the three-dimensional shape measuring apparatus 10, the coordinate group data relating to the point cloud relating to the measurement surface of the measurement object stored in the memory 15 is read by the mesh creation unit 11b of the control unit 11. .

Subsequently, mesh data (that is, surface shape data of measurement results) relating to the loaded point group (coordinate group) is calculated by the mesh creation unit 11b.

Then, the calculated surface shape data of the measurement result is stored in the memory 15 by the mesh creation unit 11b.

Next, the cross-sectional shape of the tubular portion of the object to be measured is generated (S4).

In this process, shape data is generated for each longitudinal orthogonal cross-section that is continuous in the longitudinal direction of the tubular portion that constitutes and forms the measurement surface of the object to be measured.

The shape of the cross section perpendicular to the longitudinal direction of the tubular portion is generated based on, for example, design values and initial dimensions at each position in the longitudinal direction of the tubular portion. A design value is a design dimension described in a design drawing or the like of a tubular portion of an object to be measured. The initial dimensions are the dimensions actually measured before being assembled into an actual machine and used (that is, before the start of service and before thinning due to corrosion, wear, etc.). A standard dimension, such as a design value or an initial dimension, which is used when the shape of the cross section perpendicular to the longitudinal direction of the tubular portion is generated is called a "standard dimension."

The data related to the cross-sectional shape based on the reference dimensions generated in the process of S4 is called "cross-sectional shape data".

Only one type of cross-sectional shape data is generated when the shape based on the reference dimensions at each position in the longitudinal direction of the tubular portion of the measurement object is constant/same regardless of the position in the longitudinal direction. If different depending on the position in the direction, a plurality of types are generated (in other words, they are generated for each section/range where the shape based on the reference dimension is different, and the cross-sectional shape is treated as constant/same within the section/range. can be used).

In the present embodiment, data relating to the reference dimensions of the member (at least, the portion corresponding to the tubular portion) forming the measurement surface of the object to be measured is recorded in a data file and stored in the storage unit 12.

Then, as processing in the three-dimensional shape measuring apparatus 10, the cross-sectional shape generation unit 11c of the control unit 11 configures and forms the measurement surface of the measurement object recorded in the data file stored in the storage unit 12. Reads the data for the basic dimensions of the members that are

Subsequently, the cross-sectional shape generation unit 11c uses the read reference dimensions to generate a cross-sectional shape orthogonal to the longitudinal direction (that is, cross-sectional shape data) of the tubular portion of the measurement object that is different from the shape based on the reference dimensions. generated for each interval/range

Then, the generated cross-sectional shape data is stored in the memory 15 by the cross-sectional shape generation unit 11c.

Next, the center position of the cross-sectional shape of the tubular portion of the object to be measured is calculated (S5).

In the present invention, the surface shape data of the measurement results obtained in the processing up to S3 and the internal structure data created in the processing of S7 described later based on the cross-sectional shape data generated in the processing of S4 are compared. , the wall thickness of the tubular section is calculated.

Here, the tubular part of the object to be measured that is actually installed and used in an architectural structure such as a building or a mechanical structure such as a plant (in other words, in the state of actual machine use) In other words, even if the shape is straight based on the standard dimensions, it may actually be curved instead of the shape as designed (in other words, the shape according to the standard dimensions) (Fig. 4). reference). For example, boiler water wall tubes used in side walls of boiler furnaces, particularly for power generation and waste incinerators, may be curved due to expansion due to high heat.

Therefore, if the actual curvature of the tubular portion of the object to be measured is not taken into account when the actual machine is in use, the curvature that actually occurs becomes a measurement error.

Therefore, in this process, based on the surface shape data of the measurement results, the center position of each longitudinal orthogonal cross-section continuous in the longitudinal direction of the tubular portion of the object to be measured in the state of actual machine use is obtained. The bending state of the tubular portion is grasped as a sequence of positions. This eliminates the influence of the curvature of the tubular portion itself on the calculation of the shape of the tubular portion.

The center position of the shape of the cross section orthogonal to the longitudinal direction of the tubular portion is obtained by fitting the surface shape data of the measurement results obtained in the processing up to S3 and the cross-sectional shape data generated in the processing of S4.

That is, the central position of the shape of the cross section orthogonal to the longitudinal direction of the tubular part is the outer shape (in other words, the shape corresponding to the outer dimension) of the surface shape data and the cross-sectional shape data of the measurement result. After fitting the part corresponding to the surface shape data at the position, it is determined as the center position of the outer shape.

The object to be measured in the present invention is a single tubular portion or a plurality of connected tubular portions, and the shape of the cross section perpendicular to the longitudinal direction in the surface shape data of the measurement result is circular or arc-shaped. Therefore, the center position of the cross-sectional shape of the tubular portion of the object to be measured, which is obtained in the process of S5, is specifically the center of a circle or the center of an arc.

The method of fitting circles to circles or arcs to arcs is not limited to a specific method. Such a method is also acceptable. Specifically, for example, the difference between the surface shape data of the measurement result (in other words, the coordinate group related to the surface shape of the tubular portion) and the portion of the cross-sectional shape data corresponding to the surface shape data is minimized. is calculated by the method of least squares.

The tubular portion of the object to be measured in the present invention has a hollow cylindrical shape, and the shape of the cross section perpendicular to the longitudinal direction in the surface shape data of the measurement result is circular or arc-shaped, and the outer shape of the cross section perpendicular to the longitudinal direction in the cross-sectional shape data. are also circular or arcuate. Then, the circumference or arc as the surface shape of the tubular portion of the measurement object and the circumference or arc as the cross-sectional shape, or a portion of the circumference corresponding to the arc of the surface shape (that is, the arc) are fitted. After that, the position of the center of the cross-sectional circle or arc is obtained.

In the present embodiment, the center position calculation unit 11d of the control unit 11 reads the surface shape data of the measurement result stored in the memory 15 in the process of S3, and the cross-sectional shape data stored in the memory 15 in the process of S4. is loaded.

Subsequently, the center position calculation unit 11d performs fitting between the surface shape in the surface shape data of the measurement result and the portion corresponding to the surface shape in the cross-sectional shape data, and specifies the position of the cross-sectional shape that fits the surface shape. .

Further, the center position calculation unit 11d calculates the center position (specifically, the position of the center of the circle or arc) with respect to the cross-sectional shape whose position is specified by the fitting process.

Here, the fitting of the surface shape data and the cross-sectional shape data of the measurement results in the processing of S5 and the calculation of the center position regarding the cross-sectional shape are performed within the range that the resolution of these data (in other words, the reproduction density) can support. It is preferable that the measurement is performed at every cross-sectional position spaced as closely as possible along the longitudinal direction of the tubular portion of the object to be measured. The cross-sectional shape data is generated for each section/range in which the shape is different based on the reference dimensions at each position in the longitudinal direction of the tubular portion of the measurement object in the process of S4, and the measurement result of the fitting object Depending on the surface shape data of , calculation of the center position is performed with respect to cross-sectional shape data that differs for each section/range.

A connection of the center positions of the cross-sectional shape of each section/range in the longitudinal direction of the tubular portion of the measurement object calculated by the above process (that is, the trajectory of the center position) is the tubular portion of the measurement object. This is a trajectory reflecting the actual curved state (referred to as a “cross-sectional center trajectory”).

Then, the center position calculation unit 11d causes the memory 15 to store the data regarding the calculated trajectory of the center of the cross section.

Next, the cross-section of the internal structure of the tubular portion of the object to be measured is arranged (S6).

Since the tubular portion of the object to be measured has a hollow cylindrical shape, the hollow portion forming the communicating space is the internal structure of the tubular portion, and the cross-sectional shape of the internal structure of the tubular portion in the cross section perpendicular to the longitudinal direction of the tubular portion. is circular.

In this process, the data on the trajectory of the center of the cross section calculated in the process of S5 and the wall thickness actually measured in the process of S2 are used to obtain the surface shape in the surface shape data of the measurement results obtained in the process of S3. A circle, which is the cross-sectional shape of the internal structure of the tubular portion of the object to be measured, is arranged.

Arrangement of circles as a cross-section of the internal structure of the tubular portion of the object to be measured may be performed, for example, by any one of <Method I> to <Method III> below.

<Method I> Align the central position of the cross section of the internal structure with the central position of the cross sectional shape.

In the process of S2, the thickness is actually measured at the position of the thickness measurement point whose position coordinates are specified.

In <Method I>, a circle centered on the central position of the cross-sectional shape of the tubular portion at the position of the actual thickness measurement location and passing through a point separated from the surface of the measurement object by the thickness is the internal structure. Determined as a cross section.

That is, in the position coordinates specified in the process of S2, centering on the central position of the cross-sectional shape of the tubular portion calculated in the process of S5, and in the surface shape data of the measurement result obtained in the process of S3 A circle whose circumference passes through a position spaced in the thickness direction toward the inner side of the tubular portion from the position of the surface by the thickness actually measured in the process of S2 is arranged (see FIG. 5).

In <Method I>, the thickness actually measured in the process of S2 is based on the reference dimensions at each position in the longitudinal direction of the tubular portion of the object to be measured. It may be measured at the top of the tubular portion, preferably at the top of the tubular portion.

<Method II> Arrange them at positions separated by the measured wall thickness.

In the process of S2, the thickness is actually measured at the position of the thickness measurement point whose position coordinates are specified.

In <Method II>, a circle passing through a point separated by the thickness from the surface of the measurement object at the position of the actual thickness measurement location and having a diameter equal to the reference dimension is determined as the cross section of the internal structure. .

That is, at the position coordinates specified in the process of S2, from the position of the surface in the surface shape data of the measurement result obtained in the process of S3, the inner side of the tubular portion is increased by the thickness actually measured in the process of S2. The diameter dimension of a circle that passes through a position separated in the thickness direction from 1 to , and is the cross-sectional shape of the internal structure among the cross-sectional shapes generated in the process of S4 (i.e., in the reference dimension of the tubular part A circle having a diameter equal to the inner diameter) is arranged (see FIG. 6).

In <Method II>, the thickness actually measured in the process of S2 is based on the reference dimensions at each position in the longitudinal direction of the tubular portion of the object to be measured. It may be measured at the top of the tubular portion, or it may be measured at at least two locations.

<Method III> Arrange so that it passes through a position separated by the measured wall thickness.

In the process of S2, the thickness is actually measured at the position of the thickness measurement point whose position coordinates are specified.

In <Method III>, a circle passing through a point separated by the thickness from the surface of the object to be measured at the position of the actual thickness measurement point is determined as the section of the internal structure.

That is, at the position coordinates specified in the process of S2, from the position of the surface in the surface shape data of the measurement result obtained in the process of S3, the inner side of the tubular portion is increased by the thickness actually measured in the process of S2. A circle whose circumference passes through a position spaced apart in the thickness direction toward the center is placed (see FIG. 7).

In <Method III>, the thickness actually measured in the process of S2 is based on the reference dimensions at each position in the longitudinal direction of the tubular portion of the object to be measured. It is preferable that the top portion of the tubular portion is included.

Here, cross-sectional shape data is generated for each section/range in which the shape is different based on the reference dimension at each position in the longitudinal direction of the tubular portion of the measurement object (S4), and the center position regarding the cross-sectional shape is calculated. (S5). Also, when the cross section of the internal structure is arranged, the actually measured thickness is used. For these reasons, the cross-sectional arrangement of the internal structure is arranged for each section/range where the shape is different based on the reference dimension at each position in the longitudinal direction of the tubular portion of the measurement object and for each section where the wall thickness is actually measured. done. The actual measurement of the wall thickness in the process of S2 may be performed at the above-mentioned number of points for each section/range having different shapes based on the reference dimensions at each position in the longitudinal direction of the tubular portion of the object to be measured. preferable. In addition, the shape based on the reference dimensions at each position in the longitudinal direction of the tubular part of the object to be measured is the same over the entire length of the tubular part in the longitudinal direction, and there is one place where the wall thickness is actually measured. , the placement of the cross-section of the internal structure is made only at the locations where the thickness measurements have been taken.

In the present embodiment, the internal structure cross-section arrangement unit 11e of the control unit 11 is used to correspond to any of the above-described <Method I> to <Method III> as examples of how to arrange the cross-section of the internal structure. Then, the section of the internal structure of the tubular portion is arranged by any one of the following procedures (1) to (3).

(1) When <Method I> is used to arrange cross sections of the internal structure. Combined data of the position coordinates of the actual thickness measurement locations and the actual thickness values recorded in the actual thickness measurement value data file 19 stored in the unit 12 are read.

Subsequently, the internal structure cross-section placement unit 11e uses the read locus of the center of the cross-section and the actual measurement value of the wall thickness to obtain the cross-section of the internal structure of the tubular portion of the measurement object by the above <Method I>. A calculation is made of where the circle will be placed.

Then, the internal structure cross-section placement unit 11e causes the memory 15 to store data on the calculated diameter of the circle as the cross-section of the internal structure of the tubular portion of the object to be measured and the position where the circle is placed.

(2) When <Method II> is used to arrange the cross section of the internal structure The thickness recorded in the actual thickness data file 19 stored in the storage unit 12 by the internal structure cross section placement unit 11e The combined data of the position coordinates of the actually measured locations and the actual measured values of the wall thickness are read, and the data of the member forming the measurement surface of the object to be measured recorded in the data file stored in the storage unit 12 is read. Data related to basic dimensions are read.

Subsequently, the internal structure cross-section placement unit 11e uses the read measured values of wall thickness and the reference dimensions to obtain a circle as a cross-section of the internal structure of the tubular portion of the measurement object by <Method II>. A placement calculation is made.

Then, the internal structure cross-section placement unit 11e causes the memory 15 to store data on the calculated diameter of the circle as the cross-section of the internal structure of the tubular portion of the object to be measured and the position where the circle is placed.

(3) When <Method III> is used to arrange the cross section of the internal structure The thickness recorded in the actual thickness data file 19 stored in the storage unit 12 by the internal structure cross section placement unit 11e Combined data of the position coordinates of the actually measured locations and the actual measured values of the wall thickness is read.

Subsequently, the position where the circle as the cross section of the internal structure of the tubular portion of the object to be measured is arranged by the above <Method III> using the actual measured value of the read wall thickness by the internal structure cross section placement unit 11e. is calculated.

Then, the internal structure cross-section placement unit 11e causes the memory 15 to store data on the calculated diameter of the circle as the cross-section of the internal structure of the tubular portion of the object to be measured and the position where the circle is placed.

Next, the shape of the internal structure of the tubular portion of the object to be measured is created (S7).

In this process, the shape of the internal structure of the tubular portion of the object to be measured is determined using the data on the trajectory of the cross-section center calculated in the process of S5 and the circle as the cross-section of the internal structure arranged in the process of S6. created.

The shape of the internal structure of the tubular portion of the object to be measured is created by the following ( It is performed by one of the methods 1) to (3).

(1) When <Method I> is used in the process of S6 to arrange the cross section of the internal structure In this case, the trajectory of the center of the cross section calculated in the process of S5 (in other words, ) coincides with the position of the center of the circle as the cross section of the internal structure arranged in the process of S6.

Therefore, the circle as the cross section of the internal structure arranged in the process of S6 is moved over the entire length in the longitudinal direction of the tubular part so that the center of the circle follows the trajectory of the center of the cross section calculated in the process of S5. (See FIG. 8).

(2) When <Method II> is used in the process of S6 to arrange the cross section of the internal structure In this case, the trajectory of the cross-sectional shape calculated in the process of S5 (in other words, the ) and the position of the center of the circle as the cross section of the internal structure arranged in the process of S6 may be misaligned (and may be coincident).

Therefore, the circle as the cross section of the internal structure arranged in the process of S6 is adjusted so that the center of the circle and the trajectory of the center of the cross section calculated in the process of S5 maintain a constant distance. It is moved over the entire longitudinal length of the tubular portion parallel to the trajectory of the cross-sectional center.

(3) When <Method III> is used in the process of S6 to arrange the cross section of the internal structure In this case, the trajectory of the cross-sectional shape calculated in the process of S5 (in other words, the ) and the position of the center of the circle as the cross section of the internal structure arranged in the process of S6 may be misaligned (and may be coincident).

Therefore, the circle as the cross section of the internal structure arranged in the process of S6 is adjusted so that the center of the circle and the trajectory of the center of the cross section calculated in the process of S5 maintain a constant distance. It is moved over the entire longitudinal length of the tubular portion parallel to the trajectory of the cross-sectional center.

The part through which the circle as the cross section of the internal structure passes (that is, the shape of the cross section perpendicular to the longitudinal direction of the tubular part is circular) is communicated The internal structure of the tubular portion of the object to be measured is reproduced by the hollow portion that constitutes the space. This internal structure is then created in a shape that reflects the actual curved state of the tubular portion.

The data regarding the shape of the internal structure created by the process of S7 is called "internal structure data". The internal structure data is configured to have information on the internal structure/shape of which the position from the surface of the object to be measured is specified.

In this embodiment, the internal structural shape generator 11f of the control unit 11 reads the data related to the trajectory of the cross section center stored in the memory 15 in the process of S5, and the internal structure stored in the memory 15 in the process of S6. Data regarding the diameter of the circle as a cross-section of , and the position where the circle is located are read.

Subsequently, the internal structure shape creation unit 11f uses the read trajectory of the center of the cross section, the diameter of the circle, and the position where the circle is arranged, and selects one of the above-described <Method I> to <Method III>. The shape of the internal structure of the tubular portion of the object to be measured (that is, internal structure data) is created by a method corresponding to the method used in the process of S6.

Then, the created internal structure data is stored in the memory 15 by the internal structure shape creating section 11f.

Next, the surface shape data and the internal structure data of the measurement results regarding the tubular portion of the object to be measured are compared (S8).

In this process, the surface shape data and the internal structure data of the measurement results are superimposed, and the difference between the surface shape data and the internal structure data is calculated.

That is, with respect to the tubular portion of the object to be measured, the position of the back surface is specified as the shape of the internal structure (in other words, the boundary of the internal structure) with respect to the surface shape data of the measurement result by the processing of S6 and S7. Therefore, comparison in the thickness direction of the tubular portion is possible, and the difference between the surface shape in the surface shape data of the measurement result and the shape of the internal structure/shape of the back surface as the boundary in the internal structure data can be calculated. Through this calculation, the thickness distribution of the tubular portion of the object to be measured (in other words, the member forming the surface of the object to be measured) is obtained.

In this embodiment, the thickness distribution calculation unit 11g of the control unit 11 reads the surface shape data of the measurement result stored in the memory 15 in the process of S3, and the internal structure stored in the memory 15 in the process of S7. data is loaded.

Subsequently, the thickness distribution calculator 11g calculates the difference between the surface shape in the surface shape data of the measurement result and the shape of the internal structure/shape of the back surface as the boundary in the internal structure data.

Then, the control unit 11 displays the thickness distribution of the tubular portion of the object to be measured calculated by the above-described processing, for example, on the display unit 14 or saves it as a data file or the like in the storage unit 12. The processing related to the measurement of the three-dimensional shape of the object to be measured that has been dealt with up to now ends (END).

According to the three-dimensional shape measuring method, the three-dimensional shape measuring apparatus, and the three-dimensional shape measuring program configured as described above, the surface shape of the object to be measured and the members forming the surface of the object to be measured can be measured. The thickness distribution can be grasped. Therefore, it is possible to improve the usefulness as a three-dimensional shape measuring method.

In addition, although the above-described embodiment is an example of a preferred mode for carrying out the present invention, the embodiment of the present invention is not limited to the above-described one, and the present invention can be used without departing from the scope of the present invention. Various modifications of the invention are possible.

For example, as described above, existing data may be used/organized and used as the point cloud data used in the present invention. Since they may be prepared and used, it is not an essential procedure in the present invention to prepare unique point cloud data and mesh data relating to the measurement surface of the measurement object. In this case, the actual measurement of the thickness of the tubular portion of the object to be measured is performed as a separate procedure from the processing related to the maintenance of the point cloud data (in other words, the measurement of the surface shape of the object to be measured). The actually measured positions are used in association with point group data (three-dimensional coordinate group) and mesh data relating to the measurement surface of the object to be measured.

10 computer/three-dimensional shape measuring device 11 control unit 11a data reading unit 11b mesh creation unit 11c cross-sectional shape generation unit 11d center position calculation unit 11e internal structure cross-section arrangement unit 11f internal structure shape creation unit 11g thickness distribution calculation unit 12 storage Unit 13 Input unit 14 Display unit 15 Memory 17 Three-dimensional shape measurement program 18 Point cloud data file 19 Thickness actual measurement value data file 20 Data server

Claims (3)

The thickness is measured at at least one point selected as the point where the thickness is actually measured for each section with a different shape based on the standard dimensions of the members that make up the surface of the object to be measured. A process in which the position of the actual thickness measurement location is specified while the
A process of generating a cross-sectional shape of the member constituting the surface of the object to be measured based on the reference dimension at the actual thickness measurement location of the member;
The shape of the surface of the object to be measured and the cross-sectional shape of the member are fitted to identify the position of the cross-sectional shape of the member with respect to the shape of the surface of the object to be measured, and to determine the cross-sectional shape of the member. a process in which the center position is calculated;
A process of arranging the cross section of the internal structure of the member so that the boundary of the cross section of the internal structure of the member passes through a position separated from the surface of the measurement object by the actual thickness value of the member;
a process in which the shape of the internal structure of the member is created as a portion through which the cross-section of the internal structure of the member has moved relative to the center position with respect to the cross-sectional shape of the member;
a three-dimensional shape measuring method, comprising: obtaining a thickness distribution by comparing the shape of the surface of the object to be measured and the shape of the internal structure of the member. Measure the thickness at at least one point selected as the point where the thickness is actually measured for each section with a different shape based on the standard dimensions of the members that make up the surface of the object to be measured. and a means for specifying the position of the actual thickness measurement location;
means for generating a cross-sectional shape of the member constituting the surface of the object to be measured based on the reference dimensions of the member at the actual thickness measurement location ;
fitting the shape of the surface of the object to be measured and the shape of the cross-section of the member to identify the position of the shape of the cross-section of the member with respect to the shape of the surface of the object to be measured, and the center of the shape of the cross-section of the member means for calculating position;
means for arranging the section of the internal structure of the member so that the boundary of the section of the internal structure of the member passes through a position separated from the surface of the object to be measured by the actual thickness value of the member;
means for creating the shape of the internal structure of the member as a portion through which the cross-section of the internal structure of the member has moved relative to the center position with respect to the cross-sectional shape of the member;
and means for obtaining a thickness distribution by comparing the shape of the surface of the object to be measured with the shape of the internal structure of the member. Measure the thickness at at least one point selected as the point where the thickness is actually measured for each section with a different shape based on the standard dimensions of the members that make up the surface of the object to be measured. Then, a process of specifying the position of the actual thickness measurement location;
A process of generating a cross-sectional shape of the member constituting the surface of the object to be measured based on the reference dimensions at the actual thickness measurement location of the member;
fitting the shape of the surface of the object to be measured and the shape of the cross-section of the member to identify the position of the shape of the cross-section of the member with respect to the shape of the surface of the object to be measured, and the center of the shape of the cross-section of the member a process of calculating a position;
A process of arranging the section of the internal structure of the member so that the boundary of the section of the internal structure of the member passes through a position separated from the surface of the measurement object by the actual thickness value of the member;
creating a shape of the internal structure of the member as a portion through which the cross-section of the internal structure of the member has moved relative to the center position with respect to the cross-sectional shape of the member;
A three-dimensional shape measurement program for causing a computer to perform a process of obtaining a thickness distribution by comparing the shape of the surface of the object to be measured with the shape of the internal structure of the member.

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