JP2012058076A - Three-dimensional measurement device and three-dimensional measurement method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a three-dimensional measurement device and a three-dimensional measurement method, capable of measuring the features without omission for the three-dimensional shape of the whole visual field by photographing of one time.SOLUTION: A laser pattern comprising a plurality of straight and/or curved laser lines in a plurality of directions is projected to a measurement object from laser projection means, the measurement object to which the laser pattern is projected is photographed from different directions to acquire a first image and a second image, and the laser lines are extracted from the first image and the second image. The three-dimensional coordinates of the corresponding point candidates of the laser line point of the second image corresponding to the laser line point of the first image are obtained respectively, the three-dimensional coordinates are transformed to a projection means coordinate system set to the laser projection means, whether or not respective projection points projected to a laser pattern plane where the laser pattern is configured are on the laser pattern is determined, and thus the corresponding point is obtained.

Description

  The present invention relates to a three-dimensional measurement apparatus and a three-dimensional measurement method for performing three-dimensional measurement by irradiating a measurement target with a laser pattern.

  Conventionally, as a method for obtaining a three-dimensional shape of an object, for example, a method of measuring the distance to each point by projecting a laser beam of one line onto a measurement object and measuring the reflected light, A light cutting method (for example, refer to Patent Document 1) that measures the three-dimensional shape of a measurement object by projecting pattern light onto the measurement object and measuring the shape of the pattern projected onto the measurement object. There is an active method. Further, in order to measure the shape of the measurement object, a stripe pattern is projected onto the object, and the stripe pattern is imaged a plurality of times while being phase-shifted. Identify the corresponding pixels among multiple images obtained by photographing the measurement object with two or more cameras, the so-called phase shift method that measures the object and the reference camera and reference camera provided at different positions Then, by applying the principle of triangulation to the difference (parallax) between the position of the pixel on the associated standard image and the pixel on the reference image, the measurement object corresponding to the pixel on the measurement object is applied. There is a so-called stereo method for measuring the distance to a point.

  However, in the light cutting method, a moving mechanism is required, and it takes time to measure the measurement object, and thus it is difficult to measure the moving object. In addition, there is a three-dimensional measurement system using two orthogonal line lasers as an extension of this, but as in the case of using a single line laser, the three-dimensional shape of the entire measurement object is measured. A moving mechanism is required. Further, in the phase shift method, it is necessary to photograph the measurement target object a plurality of times while shifting the fringe pattern, so that it is difficult to measure the moving object and the fringe pattern needs to be switched. Further, in the conventional stereo method, when the measurement target is an object having almost no feature such as a white wall, it is difficult to perform the association between images.

  Therefore, in order to extract feature points even from image information of a measurement object with few feature points, a plurality of pieces of image information are obtained from the imaging means by irradiating the measurement object with pattern light consisting of a plurality of parallel slit lights. In addition, a plurality of bright points are extracted as feature points from the image information, the feature points of the image information are associated with each other, and the three-dimensional shape of the measurement object is detected based on the associated feature points A detection device is disclosed (for example, see Patent Document 2).

JP 2008-292434 A JP 2009-066986 A

  However, in Patent Document 2, since pattern light composed of a plurality of parallel slit lights is used, there is a problem that one-way parallel slit light cannot always sufficiently exhibit the characteristics of the three-dimensional shape.

  The present invention has been made in view of the above problems, and a three-dimensional measurement apparatus and a three-dimensional measurement capable of measuring the characteristics of a three-dimensional shape of the entire field of view without omission in one shooting. It aims to provide a method.

  In order to achieve the above object, the three-dimensional measurement apparatus according to claim 1, a laser projection unit that projects a laser pattern constituted by a plurality of straight lines and / or curved laser lines in a plurality of directions onto a measurement object; A first imaging unit that captures a measurement object on which the laser pattern is projected and acquires a first image, and a measurement object on which the laser pattern is projected from a different direction from the first imaging unit. A stereo camera having a second imaging means for acquiring an image, a laser line extraction means for extracting the laser line from the first image and the second image, and a laser line point of the first image Corresponding point search means for obtaining corresponding points of the laser lines of the second image.

  3. The three-dimensional measurement apparatus according to claim 2, wherein a stereo camera coordinate system set in the stereo camera and the laser projection unit are set using a plane calibration board having a plane on which the laser pattern is projected in advance by the laser projection unit. And a first calibration unit that calibrates the rotation and translation between the projection unit coordinate system set to the projection unit coordinate system, and the corresponding point search unit includes the second image corresponding to the laser line point of the first image. A laser pattern plane in which the laser pattern is formed by obtaining the three-dimensional coordinates of the corresponding point candidates of the laser line and converting the three-dimensional coordinates into the projection unit coordinate system based on the result obtained by the first calibration unit. It is characterized in that a corresponding point is obtained by determining whether or not each projected point projected onto is on the laser pattern.

  The three-dimensional measurement apparatus according to claim 3, wherein a stereo camera coordinate system set in the stereo camera using a non-planar calibration object having a non-planar shape onto which the laser pattern is projected in advance by the laser projection unit, and the A second calibration unit that calibrates the rotation and translation between the projection unit coordinate system set in the laser projection unit, and the corresponding point search unit includes the second line corresponding to the laser line point of the first image. The three-dimensional coordinates of the corresponding point candidates of the laser line in the image are respectively obtained, and the three-dimensional coordinates are converted into the projection means coordinate system based on the result obtained by the second calibration means, thereby forming the laser pattern. It is characterized in that a corresponding point is obtained by determining whether or not each projection point projected onto a laser pattern plane is on the laser pattern.

  The three-dimensional measurement method according to claim 4, wherein a laser projection step of projecting a laser pattern constituted by a plurality of straight and / or curved laser lines in a plurality of directions onto a measurement object by a laser projection means, and the laser pattern projects A stereo image acquisition step of acquiring the first image and the second image by capturing the measured object by the first imaging unit and the second imaging unit of the stereo camera; and the first image and the second image A laser line extracting step for extracting the laser line from the image; and a corresponding point searching step for obtaining a corresponding point of the laser line of the second image corresponding to the laser line point of the first image. It is said.

  6. The three-dimensional measurement method according to claim 5, wherein a stereo camera coordinate system set on the stereo camera and the laser projection unit are set using a plane calibration board having a plane on which the laser pattern is projected in advance by the laser projection unit. A first calibration step for calibrating rotation and translation with respect to the projection unit coordinate system set to, and in the corresponding point search step, the second image corresponding to the laser line point of the first image A laser pattern plane in which the laser pattern is formed by obtaining three-dimensional coordinates of corresponding point candidates of the laser line and converting the three-dimensional coordinates into the projection unit coordinate system based on the result obtained in the first calibration step. It is characterized in that a corresponding point is obtained by determining whether or not each projected point projected onto is on the laser pattern.

  The three-dimensional measurement method according to claim 6, wherein a non-planar calibration object having a non-planar shape onto which the laser pattern is projected in advance by the laser projection unit, and a stereo camera coordinate system set in the stereo camera, A second calibration step for calibrating rotation and translation with respect to the projection unit coordinate system set in the laser projection unit, and in the corresponding point search step, the second corresponding to the laser line point of the first image. The three-dimensional coordinates of the corresponding point candidates of the laser line of the image in (2) are respectively obtained, and the three-dimensional coordinates are converted into the projection means coordinate system based on the result obtained in the second calibration step, whereby the laser pattern is configured. It is characterized in that a corresponding point is obtained by determining whether or not each projection point projected onto a laser pattern plane is on the laser pattern.

  According to the first and fourth aspects of the invention, since an image obtained by photographing a measurement object on which a laser pattern composed of a plurality of straight lines and / or curved laser lines in a plurality of directions is projected is used, a stereo camera is used. Thus, measurement can be performed with one shooting, and even if the measurement target having almost no feature is a moving object, the correlation can be performed with high accuracy.

  According to the second and fifth aspects of the present invention, the stereo camera coordinate system and the laser projection set in the stereo camera using the plane calibration board having a plane in advance before performing the processing of the three-dimensional measurement of the measurement object. Since the rotation and translation with respect to the projection unit coordinate system set in the unit are calibrated, the accuracy of association can be improved. In addition, by projecting the laser line point of the corresponding point candidate onto the laser pattern plane where the laser pattern is configured and determining whether it is on the laser pattern or not, the corresponding point is searched for, so the virtual image is surely excluded as the corresponding point. It is possible to perform association more reliably.

  According to the third and sixth aspects of the present invention, a non-planar calibration object that does not have a planar shape is used in advance before performing the process of three-dimensional measurement of the measurement object. The rotation and translation between the stereo camera coordinate system set for the stereo camera and the projection means coordinate system set for the laser projection means can be calibrated. Thereby, the precision of matching can be improved. In addition, by projecting the laser line point of the corresponding point candidate onto the laser pattern plane where the laser pattern is configured and determining whether it is on the laser pattern or not, the corresponding point is searched for, so the virtual image is surely excluded as the corresponding point. It is possible to perform association more reliably.

It is a schematic diagram showing an example of composition of a three-dimensional measuring device concerning a 1st embodiment of the present invention. It is a schematic diagram which shows an example of a laser pattern. It is a flowchart which shows the flow of the calibration process using a plane calibration board. It is a schematic explanatory drawing for demonstrating the method of calibration using a plane calibration board. It is a flowchart which shows the flow of the process by the three-dimensional measuring apparatus which concerns on the 1st Embodiment of this invention. It is a schematic explanatory drawing for demonstrating how to obtain | require a corresponding point. It is a schematic diagram which shows an example of a structure of the three-dimensional measuring apparatus which concerns on the 2nd Embodiment of this invention. It is a flowchart which shows the flow of the calibration process using a non-planar calibration object. It is a schematic explanatory drawing for demonstrating the method of calibration using a non-planar calibration object.

  Hereinafter, a three-dimensional measurement apparatus 1 according to a first embodiment of the present invention will be described with reference to the drawings. The three-dimensional measuring apparatus 1 performs a three-dimensional measurement by photographing a measurement object 2 onto which a laser pattern (lattice laser pattern) P is projected, and projects the laser pattern P onto the measurement object 2 as shown in FIG. The first imaging means 4a for capturing the first image and the second image (stereo image) by photographing the laser projection means 3 for performing the measurement and the measurement object 2 on which the laser pattern P is projected from different directions. And a stereo camera 4 having a second image pickup means 4b, and a computer 5 for performing arithmetic processing for three-dimensional measurement of the measurement object 2 using a stereo image input from the stereo camera 4.

  As shown in FIG. 2, the laser projection means 3 is for projecting a laser pattern P configured in a lattice shape by crossing a plurality of laser lines L in a plurality of directions onto the measurement object 2. In addition, a circular pattern T is formed at the center of the laser pattern P to facilitate the association. Note that the pattern T is not limited to a circular shape as shown in FIG. 2, but is for making it easy to distinguish adjacent laser lines L, and may have other shapes.

  The laser projection means 3 projects a laser pattern P using, for example, a dedicated DOE, and the laser pattern P has a pattern formed on a slide or the like in advance, and the measurement target is obtained by irradiating the laser through the slide. A laser pattern P1 is projected onto the surface of the object 2 as shown in FIG. In the laser pattern P shown in FIG. 2, the laser pattern P is configured in a lattice shape using a plurality of linearly formed laser lines L. However, the laser line L does not necessarily have to be a straight line and has a curved shape. The laser pattern P may be configured using a plurality of laser lines formed in the above. Further, the laser pattern P does not necessarily have a lattice shape, and is a laser pattern formed by a plurality of laser lines in a plurality of directions intersecting, and the shape may be defined in advance.

  Each of the first imaging unit 4a and the second imaging unit 4b of the stereo camera 4 includes an imaging device as a photographing unit and a lens that forms an image of the measurement object 2 on the imaging surface of the imaging device. As the image sensor, for example, an image sensor such as a charge coupled device (CCD) or a complementary metal-oxide semiconductor (CMOS) is used. The same lenses are used for the imaging means 4a and 4b, and the viewing angle and the resolution are set to be substantially the same. In addition, as the first imaging unit 4a and the second imaging unit 4b, those having substantially the same sensitivity are used. Further, when performing the three-dimensional measurement process of the measurement object 2, the camera parameters are adjusted in advance by calibrating the stereo camera 4.

  Stereo image data acquired by the stereo camera 4 is input to the computer 5. The computer 5 performs operations for obtaining three-dimensional information of the measurement object 2 using the stereo image data acquired by the stereo camera 4b, and includes a CPU (Central Processing Unit) 6, a hard disk 7, , An image processing unit 8, a RAM (Random Access Memory) 9, a display unit 10, an operation unit 11, and the like. Further, as shown in FIG. 1, these units are mutually connected to a system bus 12, and various data and the like are input / output via the system bus 12, and various processes are executed under the control of the CPU 6. The

  The hard disk 7 stores a processing program for performing three-dimensional measurement of the measurement object 2 using stereo image data or the like input from the stereo camera 4. In this embodiment, an example in which a processing program for performing three-dimensional measurement is stored in the hard disk 7 is shown, but instead, it is stored in a computer-readable storage medium (not shown). Alternatively, the processing program can be read from the recording medium.

  The image processing unit 8 performs arithmetic processing and the like for performing three-dimensional measurement of the measurement object 2 under the control of the CPU 6 based on a processing program stored in the hard disk 7. The RAM 9 temporarily stores a processing program read from the hard disk 7 and is used as a work area for the CPU 5.

  The display unit 10 is composed of a liquid crystal display or the like, and displays an image or the like acquired by the first imaging unit 4a and the second imaging unit 4b. The operation unit 11 includes a mouse, a keyboard, and the like, and is used by an operator to input various data and operation commands.

  Hereinafter, the flow of processing for performing the three-dimensional measurement of the measurement object 2 by the three-dimensional measurement apparatus 1 will be described with reference to the flowcharts of FIGS. 3 and 5. 3 and 5 is executed by the image processing unit 8 and the like under the control of the CPU 6 in accordance with a processing program stored in the hard disk 7.

  First, in performing the three-dimensional measurement processing of the measurement object 2, in order to obtain the position and the attitude of the laser projection means 3, a plane calibration board 13 as shown in FIG. The rotation and translation between the stereo camera coordinate system set for the stereo camera 4 and the projection means coordinate system set for the laser projection means 3 are calibrated by one calibration means 81. As shown in FIG. 4, the plane calibration board 13 used for calibrating the rotation and translation between the stereo camera coordinate system and the projection means coordinate system only needs to have a planar shape, and the material and the like are not particularly limited. It is not limited.

  As shown in the flowchart of FIG. 3, in performing the calibration process, first, the laser pattern P is projected onto the flat calibration board 13 by the laser projection means 3 (S101). Then, a stereo image is obtained by photographing the plane calibration board 13 on which the laser pattern P1 is projected on the surface with the stereo camera 4 (S102). The stereo image acquired in this way is input to the computer 5. The projection timing of the laser pattern P by the laser projection means 3 and the photographing timing by the stereo camera 4 are controlled to be synchronized by a timing synchronization means (not shown) of the computer 5.

Next, the first calibration unit 81 in the image processing unit 8 performs three-dimensional measurement based on the acquired stereo image and performs plane fitting on the three-dimensional coordinates of the lattice intersection M. By performing the plane fitting, a three-dimensional coordinate system of the plane calibration board 13 including an axis perpendicular to the plane calibration board 13 is obtained. Further, by projecting the grid intersection M onto the fitting plane, the two-dimensional coordinates of the grid intersection M on the plane of the plane calibration board 13 can be obtained. Then, a rotation matrix R _CS and a translation vector t _CS between the stereo camera coordinate system and the three-dimensional coordinate system of the plane calibration board 13 obtained by the above-described plane fitting are obtained from the following formula (1) (S103). Here, three-dimensional measurement is performed and plane fitting is performed on the three-dimensional coordinates of the lattice intersection M. However, with respect to the three-dimensional coordinates of feature points appearing on at least three or more planes other than the lattice intersection M. Then, the plane fitting may be performed.

  Next, the correspondence between the laser pattern P1 projected on the plane calibration board 13 and the laser pattern P on the laser pattern plane of the laser projection means 3 is obtained (S104). Specifically, for example, a pattern T1 projected on the plane calibration board 13 is first extracted from the acquired stereo image, and this point is associated with the pattern T on the laser pattern P on the laser pattern plane. Then, by associating the two laser lines L1 passing through the pattern T1 with the laser lines L on the laser pattern plane, the planes can be associated with each other. Here, the laser pattern plane is a plane on which the laser pattern P of the laser projection means 3 is formed, and this plane is defined in advance when the laser pattern P is formed.

Then, as represented by the following mathematical formula (2), the two-dimensional coordinates of the lattice intersection M of the laser pattern P1 on the plane calibration board 13 obtained based on the stereo image acquired by the stereo camera 4 and the laser pattern plane A homography transformation matrix H established between the two-dimensional coordinates of the corresponding point is obtained, and a rotation matrix R _lpc and a translation vector t _lpc between the calibration board coordinate system and the projection unit coordinate system are calculated from the homography transformation matrix. (S105). The homography matrix H can be obtained if n is 4 or more. Further, the focal length f of the laser projection means 3 can also be obtained from the homography matrix H at the same time as shown in Equation (2).

Then, the rotation and translation between the stereo camera coordinate system and the projection unit coordinate system are calibrated via the plane calibration board 13 (S106). Specifically, the following formula (3) is obtained by substituting the formula (1) into the formula (2). By substituting 3-dimensional coordinates in the stereo camera coordinate system X _S in the equation (3), two-dimensional coordinates X _lpc corresponding Rezapatan _plane, it is possible to calculate the y _lpc. Therefore, the corresponding points can be obtained by using the mathematical formula (3).

  Thus, before performing the three-dimensional measurement process of the measurement object 2, the rotation and translation between the stereo camera coordinate system and the projection unit coordinate system are calibrated in advance using the plane calibration board 13. Then, three-dimensional measurement of the measurement object 2 is performed as shown in the flowchart of FIG.

  As shown in FIG. 5, first, the three-dimensional measuring apparatus 1 projects the laser pattern P onto the measurement object 2 by the laser projection means 3 (S201). Then, the first object and the second image (stereo image) are obtained by photographing the measurement object 2 on which the laser pattern P1 is projected on the surface with the first imaging unit 4a and the second imaging unit 4b (stereo camera 4). ) Is acquired (S202). The stereo image acquired in this way is input to the computer 5.

  Next, the laser line L is extracted from the stereo image acquired by the laser line extraction means 82 in the image processing unit 8 (S203). Then, in the corresponding point search means 83, all the laser line points within the predetermined parallax range along the epipolar line of the second image per one point of the laser line L of the first image extracted in this way. Is the corresponding point candidate, and the three-dimensional coordinate calculation means 83a obtains the three-dimensional coordinates for the laser line point of each corresponding point candidate (S204). In FIG. 6, for each point A of the laser line L of the first image, the laser line points A ′ and B ′ along the epipolar line of the second image are taken as corresponding point candidates, and similarly, the laser line of the first image An example is shown in which laser line points A ′ and B ′ along the epipolar line of the second image are used as corresponding point candidates for one point B of L.

The coordinate conversion unit 83b converts the coordinate system of the obtained three-dimensional coordinates of the laser line point into the projection unit coordinate system (S205). Then, the projection unit 83c projects the laser line point converted into the projection unit coordinate system onto the laser pattern plane as shown in FIG. 6 (S206). Specifically, by substituting the 3-dimensional coordinates X _S of the corresponding point candidate in the formula (3) obtained by the first calibration means 81, the coordinates of the projection point to the corresponding Rezapatan plane is determined.

  The corresponding point determining means 83d determines whether or not the projection point thus obtained is on the laser pattern P on the laser pattern plane (S207). If the corresponding point determining unit 83d determines that the projected point is on the laser pattern P (S207: YES), the corresponding point candidate is accepted and the result is output (S208).

  On the other hand, when the corresponding point determining means 83d determines that the projected point is not on the laser pattern (S207: NO), it is determined whether or not other corresponding point candidates remain (S209). When it is determined that there are candidates remaining (S209: YES), the coordinates of the points projected onto the laser pattern plane are obtained using Equation (3) for the corresponding point candidates (S206, S207), and the projected points are determined. It is determined again whether it is on the laser pattern P on the laser pattern plane (S207). This process is repeated until a corresponding point is found, thereby searching for a corresponding point. In the example shown in FIG. 6, the point A on the laser line L in the first image coincides with the laser pattern P when AA ′ is projected onto the laser pattern plane, so that A ′ in the second image is Accepted as a corresponding point, B 'is rejected. Further, the point B on the laser line L in the first image matches the laser pattern P when BB ′ is projected onto the laser pattern plane, so that B ′ in the second image is accepted as a corresponding point. , A 'is rejected. By performing such processing, it is possible to prevent an erroneous corresponding point such as a virtual image from being selected as the corresponding point, and it is possible to perform the association with high accuracy.

  In the present embodiment, three-dimensional coordinates of corresponding point candidates of the laser line of the second image corresponding to the laser line point of the first image are obtained, respectively, and the mathematical formula obtained by the first calibration unit 81 is obtained. Corresponding points are obtained by determining whether or not each projected point that has been converted into the projection means coordinate system based on (3) and projected onto the laser pattern plane is on the laser pattern P. You may comprise so that the matching process of this may be performed.

  Next, a three-dimensional measurement apparatus 1a according to the second embodiment will be described with reference to FIGS. As shown in FIG. 7, the three-dimensional measurement apparatus 1 a has substantially the same configuration as the three-dimensional measurement apparatus 1 according to the first embodiment, and includes a second calibration unit 81 a instead of the first calibration unit 81. Is. Therefore, the same reference numerals are given to the same components and the like as those of the three-dimensional measurement apparatus 1 according to the first embodiment, and detailed description thereof is omitted.

  In the three-dimensional measuring apparatus 1a, as shown in FIG. 9, a stereo camera coordinate system and a projection unit coordinate system are used by a second calibration unit 81a using a non-planar calibration object 14 having a non-planar shape instead of the plane calibration board 13. Calibrate rotation and translation between The non-planar calibration object 14 is not limited to an object having a curved surface shape as shown in FIG. 9, and it is possible to use an object obtained by bending the planar shape.

  Hereinafter, the flow of the calibration process by the second calibration unit 81a using the non-planar calibration object 14 will be described with reference to the flowchart of FIG. In performing the calibration process, first, the laser projection unit 3 projects the laser pattern P onto the non-planar calibration object 14 (S301). Then, a stereo image is acquired by photographing the non-planar calibration object 14 on which the laser pattern P1 is projected on the surface with the stereo camera 4 (S302).

  Next, the second calibration unit 81a in the image processing unit 8 performs three-dimensional measurement of the lattice intersection M of the laser pattern P1 projected on the non-planar calibration object 18 based on the acquired stereo image (S303). Then, the correspondence relationship between the laser pattern P1 projected on the non-planar calibration object 14 and the laser pattern P on the laser pattern plane of the laser projection means 3 is obtained (S304).

Then, a projection matrix P established between the three-dimensional coordinates of the lattice intersection M of the laser pattern P1 measured by the process of S303 and the two-dimensional coordinates of the corresponding points on the laser pattern plane is calculated using the following formula (4). (S305).

As shown in Equation (5), the rotation matrix R _lps and the translation vector t _lps between the stereo camera coordinate system and the projection unit coordinate system are obtained from the projection matrix P (S306). The projection matrix P can be obtained if n in the formula (4) is 6 or more.

Then, the following formula (6) is obtained by substituting the formula (5) into the formula (4). By substituting 3-dimensional coordinates in the stereo camera coordinate system X _S in the equation (6), two-dimensional coordinates X _lpc corresponding Rezapatan _plane, it is possible to calculate the y _lpc. Therefore, the corresponding points can be obtained by using the equation (6).

  In this way, the rotation and translation between the stereo camera coordinate system and the projection unit coordinate system using the non-planar calibration object 14 having a non-planar shape instead of the plane calibration board 13 by the processing by the second calibration unit 81a. Can also be calibrated.

  Note that the embodiment of the present invention is not limited to the above-described embodiment, and it is needless to say that the embodiment can be appropriately changed without departing from the scope of the idea of the present invention.

  The three-dimensional measuring apparatus and the three-dimensional measuring method according to the present invention can be effectively used as a technique for performing three-dimensional measurement of a static or dynamic measurement object with high accuracy.

DESCRIPTION OF SYMBOLS 1, 1a Tertiary measuring device 2 Measurement object 3 Laser projection means 4 Stereo camera 4a First imaging means 4b Second imaging means 81 First calibration means 81a Second calibration means 82 Laser line extraction means 83 Corresponding point search means 13 Plane Calibration board 14 Non-planar calibration object P Laser pattern (grating laser pattern)
L Laser line

Stereo image data acquired by the stereo camera 4 is input to the computer 5. Computer 5, which performs arithmetic operations for obtaining three-dimensional information of the measurement object 2 by using the stereo image data obtained by the stereo camera 4b, a CPU (Central Proceessing Unit) 6, the hard disk 7 An image processing unit 8, a RAM (Random Access Memory) 9, a display unit 10, an operation unit 11, and the like. Further, as shown in FIG. 1, these units are mutually connected to a system bus 12, and various data and the like are input / output via the system bus 12, and various processes are executed under the control of the CPU 6. The

In the hard disk 7 stores a processing program for performing three-dimensional measurement of the measurement object 2 by using the stereo image data or the like input from the stereo camera 4. In this embodiment, an example in which a processing program for performing three-dimensional measurement is stored in the hard disk 7 is shown, but instead, it is stored in a computer-readable storage medium (not shown). Alternatively, the processing program can be read from the recording medium.

The image processing unit 8 performs arithmetic processing and the like for performing three-dimensional measurement of the measurement object 2 under the control of the CPU 6 based on a processing program stored in the hard disk 7. The RAM 9 temporarily stores a processing program read from the hard disk 7 and is used as a work area for the CPU 6 .

Claims (6)

Laser projection means for projecting a laser pattern constituted by a plurality of straight and / or curved laser lines in a plurality of directions onto a measurement object;
A first imaging unit that captures a measurement object on which the laser pattern is projected and acquires a first image, and a measurement object on which the laser pattern is projected from a different direction from the first imaging unit. A stereo camera having second imaging means for acquiring an image;
Laser line extraction means for extracting the laser line from the first image and the second image;
And a corresponding point search means for obtaining corresponding points of the laser lines of the second image corresponding to the laser line points of the first image. Between a stereo camera coordinate system set for the stereo camera and a projection means coordinate system set for the laser projection means, using a plane calibration board having a plane on which the laser pattern is projected in advance by the laser projection means. First calibration means for calibrating the rotation and translation of
The corresponding point search means obtains three-dimensional coordinates of corresponding point candidates of the laser line of the second image corresponding to the laser line point of the first image, and the three-dimensional coordinates are obtained by the first calibration means. Based on the obtained result, it is converted to the projection means coordinate system, and it is determined whether or not each projection point projected onto the laser pattern plane on which the laser pattern is configured is on the laser pattern, thereby determining the corresponding point. The three-dimensional measuring apparatus according to claim 1, wherein the three-dimensional measuring apparatus is obtained. A stereo camera coordinate system set for the stereo camera and a projection means coordinate system set for the laser projection means using a non-planar calibration object having a non-planar shape, onto which the laser pattern has been projected in advance by the laser projection means. Second calibration means for calibrating rotation and translation between
The corresponding point search means obtains three-dimensional coordinates of corresponding point candidates of the laser lines of the second image corresponding to the laser line points of the first image, and the three-dimensional coordinates are obtained by the second calibration means. Based on the obtained result, it is converted to the projection means coordinate system, and it is determined whether or not each projection point projected onto the laser pattern plane on which the laser pattern is configured is on the laser pattern, thereby determining the corresponding point. The three-dimensional measuring apparatus according to claim 1, wherein the three-dimensional measuring apparatus is obtained. A laser projection step of projecting a laser pattern constituted by a plurality of straight lines and / or curved laser lines in a plurality of directions onto a measurement object by a laser projection unit;
A stereo image acquisition step of acquiring the first image and the second image by capturing the measurement object on which the laser pattern is projected by the first imaging unit and the second imaging unit of the stereo camera;
A laser line extraction step of extracting the laser line from the first image and the second image;
And a corresponding point search step for obtaining a corresponding point of the laser line of the second image corresponding to the laser line point of the first image. Between a stereo camera coordinate system set for the stereo camera and a projection means coordinate system set for the laser projection means, using a plane calibration board having a plane on which the laser pattern is projected in advance by the laser projection means. A first calibration step for calibrating the rotation and translation of
In the corresponding point search step, three-dimensional coordinates of corresponding point candidates of the laser line of the second image corresponding to the laser line point of the first image are respectively obtained, and the three-dimensional coordinates are obtained in the first calibration step. Based on the obtained result, it is converted to the projection means coordinate system, and it is determined whether or not each projection point projected onto the laser pattern plane on which the laser pattern is configured is on the laser pattern, thereby determining the corresponding point. The three-dimensional measurement method according to claim 4, wherein the three-dimensional measurement method is obtained. A stereo camera coordinate system set for the stereo camera and a projection means coordinate system set for the laser projection means using a non-planar calibration object having a non-planar shape, onto which the laser pattern has been projected in advance by the laser projection means. A second calibration step for calibrating rotation and translation between
In the corresponding point search step, three-dimensional coordinates of corresponding point candidates of the laser line of the second image corresponding to the laser line point of the first image are obtained, respectively, and the three-dimensional coordinates are obtained in the second calibration step. Based on the obtained result, it is converted to the projection means coordinate system, and it is determined whether or not each projection point projected onto the laser pattern plane on which the laser pattern is configured is on the laser pattern, thereby determining the corresponding point. The three-dimensional measurement method according to claim 4, wherein the three-dimensional measurement method is obtained.

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