Shape measurement system

Abstract

To provide a shape measurement system capable of highly accurately measuring a three dimensional shape of an object conveyed by a carriage.SOLUTION: A shape measurement system 1 includes: one or more two dimensional scanners 40 that measure two dimensional shape data of a white body 2 being transported while being mounted on a carriage 10; a plurality of imaging devices 50 that images the carriage 10; a carriage position and posture calculation unit that calculates a position and a posture of the carriage 10 based on an imaging result of the plurality of imaging devices 50; a coordinate conversion unit that converts the two dimensional shape data from a three dimensional coordinates system based on the two dimensional scanners 40 to a three dimensional coordinates system corresponding to the imaging results of the plurality of imaging devices 50 based on calculation results of the carriage position and posture calculation unit 73b; and a shape calculation unit that calculates a three dimensional shape data of an object based on the converted two dimensional shape data and the calculation results of the carriage position and posture calculation unit.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to a technique for measuring the three-dimensional shape of an object. [Background technology]

[0002] During vehicle manufacturing, the shape of the body-in-white, which is the vehicle body before painting, is measured to correct scratches, dents, and assembly distortions on the vehicle body. The shape of a body-in-white as an object is measured by moving and rotating a scanner in a specific direction while the body-in-white is kept stationary. Such shape measurement methods have had problems in terms of measurement efficiency and cost, such as the need for a dedicated measurement space in which the body-in-white is placed in a stationary state, the time and effort required to move to and from the dedicated measurement space before and after measurement, the long measurement time required, and the need for dedicated measurement equipment.

[0003] In response to this, Patent Document 1 describes a technology in which, when measuring the three-dimensional shape of an object being transported, the amount of height fluctuation due to disturbances is estimated based on shape data, and the estimated amount of height fluctuation is subtracted to obtain the three-dimensional shape of the object. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Patent No. 6380667 Summary of the Invention [Problem to be solved by the invention]

[0005] In contrast, when transporting a white body (object) using a cart, not only vertical misalignment occurs, but also lateral misalignment relative to the direction of travel of the cart and misalignment in the direction of rotation (yaw, pitch, roll) of the cart, but the technology described in Patent Document 1 cannot deal with these misalignments.

[0006] The present invention has been made in view of the above points, and an object of the present invention is to provide a shape measurement system that can measure with high accuracy the three-dimensional shape of an object transported by a cart. [Means for solving the problem]

[0007] In order to solve the above-mentioned problems, the shape measurement system of the present invention is characterized by comprising one or more two-dimensional scanners that measure two-dimensional shape data of an object that is mounted on a cart and being transported; a plurality of imaging devices that image the cart; a cart position and orientation calculation unit that calculates the position and orientation of the cart based on the imaging results of the plurality of imaging devices; a coordinate conversion unit that converts the two-dimensional shape data from a three-dimensional coordinate system based on the two-dimensional scanner to a three-dimensional coordinate system that corresponds to the imaging results of the plurality of imaging devices based on the calculation results of the cart position and orientation calculation unit; and a shape calculation unit that calculates three-dimensional shape data of the object based on the converted two-dimensional shape data and the calculation results of the cart position and orientation calculation unit. [Effects of the Invention]

[0008] According to the present invention, the three-dimensional shape of an object is measured while correcting lateral deviations relative to the direction of travel of the carriage and deviations in the rotational (yaw, pitch, roll) directions of the carriage, thereby enabling the three-dimensional shape of the object to be measured with high accuracy. [Brief explanation of the drawings]

[0009] [Figure 1] FIG. 1 is a plan view schematically showing a shape measurement system according to an embodiment of the present invention. [Figure 2] 1 is a block diagram schematically illustrating a shape measurement system according to an embodiment of the present invention. [Figure 3] FIG. [Figure 4] 10 is a table schematically showing an example of measurement results of a two-dimensional scanner filed by the first terminal device. [Figure 5]10 is a table schematically showing an example of calculation results of the position and attitude of the cart, which are filed by the second terminal device. [Figure 6] FIG. 1 is a perspective view schematically showing measurement of an object by a two-dimensional scanner. [Figure 7] FIG. 1 is a perspective view schematically showing measurement of an object by a two-dimensional scanner, and is a diagram for explaining correction of a change in the posture of the object. DETAILED DESCRIPTION OF THE INVENTION

[0010] Next, an embodiment of the present invention will be described in detail with reference to the drawings, taking as an example a case where the shape measurement system of the present invention is applied to measuring the shape of a vehicle body (white body). In the following description, the same components are given the same reference numerals, and duplicated explanations will be omitted.

[0011] 1, a shape measurement system 1 according to an embodiment of the present invention is a system for measuring the three-dimensional shape of a body-in-white 2 as an object. In this embodiment, the shape measurement system 1 measures the three-dimensional shape of the outer surface of the body-in-white 2 and determines the presence or absence of scratches, dents, assembly distortions, etc. on the body-in-white 2 by comparing the measured three-dimensional shape with a pre-stored three-dimensional design shape (vehicle body data).

[0012] <White body (target object)> The body-in-white 2 is a vehicle body that has been assembled (welded) but has not yet been painted during the automobile manufacturing process. The three-dimensional shape system 1 determines whether the three-dimensional shape of the body-in-white 2, which is a vehicle body before painting, is acceptable, thereby enabling vehicle body correction to be achieved in a shorter time and at lower cost than when the shape of the vehicle body is measured and corrected after painting.

[0013] As shown in FIGS. 1 and 2, the shape measurement system 1 includes a carriage 10, a jig 20, a synchronization device 30, one or more (in this embodiment, multiple) two-dimensional scanners 40, multiple image capture devices 50, a first terminal device 60, a second terminal device 70, and a third terminal device 80. As shown in FIG. 2, the synchronization device 30 is communicatively connected to the one or more two-dimensional scanners 40 and the multiple image capture devices 50. The one or more two-dimensional scanners 40 are communicatively connected to the first terminal device 60. The multiple image capture devices 50 are communicatively connected to the second terminal device 70, and together with the second terminal device 70, constitute a motion capture system that analyzes the three-dimensional movement of an object. The first terminal device 60 and the second terminal device 70 are each communicatively connected to the third terminal device 80.

[0014] <Cart> As shown in Fig. 1, the bogie 10 is a device that can run on a floor surface 3 or on rails 4 laid on the floor surface 3 with a body-in-white 2 placed on it. The bogie 10 includes a loading platform 11, a plurality of wheel units 12, and a plurality of markers 13.

[0015] <Cargo area> The loading platform 11 is a plate-shaped metal member on which the body-in-white 2 can be placed.

[0016] <Wheel section> The wheel unit 12 is attached to each of the four corners of the bottom surface of the loading platform 11 so as to be rotatable in both forward and reverse directions and to be able to steer. The wheel unit 12 rotates on the rails 4, thereby moving the loading platform 11 along the rails 4.

[0017] Marker The marker 13 is attached to the side of the loading platform 11. In this embodiment, the marker 13 has a hemispherical shape that protrudes from the loading platform 11, and is a reflective sphere that can reflect light (infrared rays).

[0018] Such a carriage 10 includes a drive source (not shown), a power transmission unit that transmits the power generated by the drive source to the wheel unit 12, etc., and automatically travels on the rail 4 based on the operation of an operator.

[0019] <X’Y’Z’ coordinate system> Here, the X’Y’Z’ coordinate system, which is one of the three-dimensional coordinate systems, will be described. The X’Y’Z’ coordinate system is a coordinate system based on the carriage 10 and is used when obtaining the position and orientation of the carriage 10 in the XYZ coordinate system based on the jig 20 described later. The X’Y’Z’ coordinate system is composed of an origin O’ and an X’ axis, a Y’ axis, and a Z’ axis that are orthogonal to each other and pass through the origin O’. The origin O’ is a reference position set on the carriage 10 (the center of the upper surface of the loading part 11 (the mounting surface on which the white body 2 is placed)). The X’ axis is an axis extending in the front-rear direction of the carriage 10. The Y’ axis is an axis extending in the vertical direction. The Z’ axis is an axis extending in the width direction of the carriage 10. When the carriage 10 travels on the rail 4, the position of the origin O’ moves with respect to the XYZ coordinate system described later. Also, the X’ axis, Y’ axis, and Z’ axis may be inclined with respect to the X axis, Y axis, and Z axis, respectively.

[0020] <Jig> The jig 20 is a tool (alignment jig) for aligning the XYZ coordinate system, which is a three-dimensional coordinate system in the imaging results of the plurality of imaging devices 50, and the xyz coordinate system, which is a three-dimensional coordinate system in the measurement results of the two-dimensional scanner 40. As shown in FIG. 3, the jig 20 includes a frame part 21 and a plurality of markers 22 arranged on the frame part 21.

[0021] The frame part 21 has a substantially right-angled isosceles triangular frame shape and defines the origin of the three-dimensional coordinate system at the corner part presenting a right angle. The frame part 21 is attached to the support part 5 that can be installed at a desired position on the floor surface 3 via a bracket 6 so that the posture of the frame part 21 can be changed.

[0022] The marker 22 is attached to the frame portion 21. In the present embodiment, the marker 22 has a hemispherical shape protruding from the frame portion 21 and is a reflecting sphere capable of reflecting light (infrared rays).

[0023] <XYZ coordinate system> Here, the XYZ coordinate system, which is one of the three-dimensional coordinate systems, will be described. The XYZ coordinate system is a coordinate system for describing the position and orientation of an object (the carriage 10) imaged by a plurality of imaging devices 50. The XYZ coordinate system is composed of an origin O and an X-axis, a Y-axis, and a Z-axis that pass through the origin O and are orthogonal to each other. The origin O is a position defined by a jig (not shown). The X-axis is an axis extending in the traveling direction of the carriage 10 (the laying direction of the rail 4). The Y-axis is an axis extending in the vertical direction. The Z-axis is an axis extending in a direction orthogonal to the traveling direction of the carriage 10 (the laying direction of the rail 4) in a plan view.

[0024] As a preliminary preparation for shape measurement, the control unit 73 of the second terminal device 70 described later calculates the posture and relative positions of the plurality of imaging devices 50 based on the imaging results of a jig called a wand (or calibrator) by the plurality of imaging devices 50. Further, the control unit 73 of the second terminal device 70 defines the origin O of the XYZ coordinate system and the X-axis, Y-axis, and Z-axis based on the imaging results of a jig called a grand plane (or calibration square) by the plurality of imaging devices 50.

[0025] <Synchronization device> The synchronization device 30 is a device for synchronizing the measurement timing of one or more two-dimensional scanners 40 and the imaging timing of the plurality of imaging devices 50. In the present embodiment, the synchronization device 30 synchronizes the emission timings of one or more two-dimensional scanners 40 and the plurality of imaging devices 50 as the measurement timing and imaging timing described above. As shown in FIG. 2, the synchronization device 30 includes an operation unit 31 and a control unit 32.

[0026] ≪Operation unit≫ The operation unit 31 is configured with buttons and the like, and outputs a control signal (operation result) to the control unit 32 based on an operation of the operation unit 31 by an operator.

[0027] <Control Unit> The control unit 32 is composed of a CPU (Central Processing Unit), ROM (Read-Only Memory), RAM (Random Access Memory), input / output circuits, etc. The control unit 32 transmits pulse signals for synchronization to the two-dimensional scanner 40 and the multiple imaging devices 50 based on the operation of the operation unit 31 by the operator.

[0028] <2D scanner> As shown in Fig. 1, the two-dimensional scanner 40 is a device that measures the distance from the two-dimensional scanner 40 to an object (body-in-white 2). A plurality of two-dimensional scanners 40 are arranged on a semicircle surrounding the dolly 10 when viewed from the direction of travel of the dolly 10. Note that Fig. 1 shows two two-dimensional scanners 40 arranged on the outer sides of the dolly 2 in the width direction. As shown in Fig. 2, the two-dimensional scanner 40 includes a light-emitting unit 41, a light-receiving unit 42, and a control unit 43.

[0029] <Light-emitting part> The light emitting unit 41 periodically irradiates the body-in-white 2 with an infrared laser based on a control signal from the control unit 33. The infrared laser has, for example, a linear shape extending in the vertical direction.

[0030] ≪Light receiving part≫ The light receiving unit 42 receives reflected light that is emitted from the light emitting unit 41 (infrared laser) and reflected from the body-in-white 2. The light receiving unit 42 receives the reflected light for each of a plurality of pixels arranged in the vertical direction, and outputs the light reception result (received light intensity) for each pixel to the control unit 43.

[0031] <Control Unit> The control unit 43 is composed of a CPU, a ROM, a RAM, an input / output circuit, etc. The control unit 43 receives the synchronization signal transmitted by the synchronization device 20, and controls the light emitting unit 41 based on the received synchronization signal. The control unit 43 calculates the coordinates (0, y, z) of the white body 2 in the three-dimensional coordinate system (xyz coordinate system) with the two-dimensional scanner 30 as the origin, for each pixel, based on the time when the irradiation light is irradiated by the light emitting unit 41 and the time when the reflected light is received by the light receiving unit 42.

[0032] More specifically, the control unit 43 calculates the coordinate z, which is the distance to the white body 2, at predetermined intervals in the y-axis direction, for example, at 240 frames per second. Frame 0: (y0, z 0·0 ), (y1, z 0·1 ), …, (y N , z 0·N ) Frame 1: (y0, z 1·0 ), (y1, z 1·1 ), …, (y N , z 1·N ) … Frame F: (y0, z F·0 ), (y1, z F·1 ), …, (y N , z F · N ) Here, the subscript of the y coordinate represents the order n (n = 0, 1, 2, …, N) of the point cloud data arranged in the y-axis direction. The left side of the subscript of the z coordinate represents the order f (f = 0, 1, 2, …, F) of the frames. The right side of the subscript of the z coordinate represents the order n (n = 0, 1, 2, …, N) of the point cloud data arranged in the y-axis direction.

[0033] The control unit 43 transmits a set (point cloud data) of the calculated coordinates (0, y, z) (in this embodiment, since the x coordinate is always zero, the x coordinate is omitted as (y, z)) to the first terminal device 60 for each frame.

[0034] <xyz coordinate system> Here, we will explain the xyz coordinate system, which is one type of three-dimensional coordinate system. As shown in Fig. 1, the xyz coordinate system is a coordinate system based on one two-dimensional scanner 40, and is used to describe the shape of a scanned object as point cloud data. The xyz coordinate system is composed of an origin o and x-, y-, and z-axes that pass through the origin o and are perpendicular to each other. The origin o is the position where the two-dimensional scanner 40 is installed. The x-axis is an axis extending in a direction perpendicular to the width direction and irradiation direction of the infrared laser by the two-dimensional scanner 40. The y-axis is an axis extending in the width direction of the infrared laser of the two-dimensional scanner 40. The z-axis is an axis extending in the direction of irradiation of the infrared laser by the two-dimensional scanner 40.

[0035] Such an xyz coordinate system is set individually for each of the plurality of two-dimensional scanners 40.

[0036] <Imaging device> The imaging device 50 is a device that captures an image of the dolly 10 as a rigid body. The multiple imaging devices 50 are arranged to surround the traveling dolly 10 in a plan view, and are each fixed at a predetermined position. As shown in FIG. 2 , the imaging device 50 includes a light emitting unit 51, an imaging unit 52, and a control unit 53.

[0037] <Light-emitting part> The light emitting unit 51 periodically irradiates the carriage 2 with an infrared laser based on a control signal from the control unit 53 .

[0038] <Imaging unit> The imaging unit 52 includes a plurality of pixels arranged in a grid pattern on a plane. The imaging unit 52 outputs the imaging result (including the infrared laser light reception result) for each pixel to the control unit 53.

[0039] <Control Unit> The control unit 53 is configured with a CPU, a ROM, a RAM, an input / output circuit, etc. The control unit 53 receives a synchronization signal transmitted by the synchronization device 20, and controls the light emitting unit 51 based on the received synchronization signal. The control unit 53 acquires the imaging result output from the imaging unit 52, and transmits the acquired imaging result to the first terminal device 50.

[0040] <First terminal device> The first terminal device 60 is a device that manages the measurement results of the two-dimensional scanner 40. The first terminal device 60 includes an operation unit 61, a display unit 62, and a control unit 63.

[0041] ≪Operation section≫ The operation unit 61 is configured with a keyboard, a mouse, a touch panel, etc., and outputs a control signal (operation result) to the control unit 63 based on an operation of the operation unit 61 by an operator.

[0042] ≪Display section≫ The display unit 62 is configured by a monitor or the like, and displays files (described later) in response to the operation of the operation unit 61 by the operator.

[0043] <Control Unit> The control unit 63 is composed of a CPU, ROM, RAM, input / output circuits, etc. The control unit 63 acquires the measurement results of the two-dimensional scanner 40 and transmits the acquired measurement results to the second terminal device 80. The control unit 63 also generates a file containing the acquired measurement results based on the operation result of the operation unit 61 by the operator, and stores the generated file in the storage unit 63a (see FIG. 4). In the file shown in FIG. 4, multiple measurement results in the y-axis direction are stored arranged horizontally, and these multiple measurement results are stored arranged vertically for each frame.

[0044] <Second terminal device> The second terminal device 70 is a device that manages the imaging results of the multiple imaging units 50. The second terminal device 70 includes an operation unit 71, a display unit 72, and a control unit 73.

[0045] The operation unit 71 is configured with a keyboard, a mouse, a touch panel, etc., and outputs a control signal (operation result) to the control unit 73 based on an operation of the operation unit 71 by an operator.

[0046] The display unit 72 is configured by a monitor or the like, and displays files (described later) in response to the operation of the operation unit 71 by the operator.

[0047] <Control unit> The control unit 73 is configured with a CPU, a ROM, a RAM, an input / output circuit, etc. The control unit 73 includes a carriage position and attitude calculation unit 73b as a functional unit.

[0048] <Carriage position and attitude calculation unit> The dolly position and orientation calculation unit 73b acquires imaging results from the multiple imaging devices 50, and calculates the position and orientation of the reference position (center) of the dolly 10 in a three-dimensional coordinate system (XYZ coordinate system) based on the acquired imaging results. The dolly position and orientation calculation unit 73b identifies markers 13 included in the imaging results from the multiple imaging devices 50, and aligns the identified markers 13. The dolly position and orientation calculation unit 73b calculates the position and orientation of the dolly 10 as a rigid body based on the alignment result of the markers 13. Furthermore, the dolly position and orientation calculation unit 73b tracks the movement (changes in position and orientation) of the dolly 10 by tracking the markers 13 over multiple consecutive frames.

[0049] The carriage position and attitude calculation unit 73b calculates the rotations RX, RY, RZ, and W of the reference position (center) of the carriage 10 as the attitude of the carriage 10. RX is the rotation angle of the X' axis of the cart 10 relative to the X axis of the XYZ coordinate system. RY is the rotation angle of the Y' axis of the carriage 10 relative to the Y axis of the XYZ coordinate system. RZ is the rotation angle of the Z' axis of the carriage 10 relative to the Z axis of the XYZ coordinate system. W is a quaternion corresponding to the above-mentioned RX, RY, and RZ, and is used for the rotation matrix described below.

[0050] Moreover, the carriage position and attitude calculation unit 73b calculates the coordinates X, Y, and Z of the reference position (center) of the carriage 10 as the position of the carriage 10. X is the coordinate in the X-axis direction of the XYZ coordinate system. Y is the coordinate in the Y-axis direction of the XYZ coordinate system. Z is the coordinate in the Z-axis direction of the XYZ coordinate system.

[0051] That is, the carriage position and orientation calculation unit 73b calculates the position and orientation of the reference position (center) of the carriage 10 at, for example, 240 frames per second. 0th frame: (RX0,RY0,RZ0,W0,X0,Y0,Z0) 1st frame: (RX1, RY1, RZ1, W1, X1, Y1, Z1) … F frame: (RX F ,RY F ,RZ F ,W F ,X F ,Y F ,Z F )

[0052] The cart position and attitude calculation unit 73b generates a file having the calculated position (X, Y, Z) and attitude (RX, RY, RZ, W) of the cart 10 based on the result of the operator's operation of the operation unit 71, and stores the generated file in the storage unit 73a (see FIG. 5). In the file shown in FIG. 5, the calculation results of the position and attitude of the cart 10 are stored arranged horizontally, and the calculation results are stored arranged vertically for each frame. Furthermore, the carriage position and attitude calculation unit 73b transmits the calculated position (X, Y, Z) and attitude (RX, RY, RZ, W) of the carriage 10 to the third terminal device 80 for each frame.

[0053] <Third terminal device> The third terminal device 80 is a device that measures the shape of the cart 10 based on the measurement results of the two-dimensional scanner 40 and the imaging results of the multiple imaging devices 50, and judges whether the measured shape of the cart 10 is good or bad. The third terminal device 80 includes an operation unit 81, a display unit 82, and a control unit 83.

[0054] ≪Operation section≫ The operation unit 81 is configured with a keyboard, a mouse, a touch panel, etc., and outputs a control signal (operation result) to the control unit 83 based on an operation of the operation unit 81 by an operator.

[0055] ≪Display section≫ The display unit 82 is configured by a monitor or the like, and displays the determination results described below in response to the operation of the operation unit 81 by the operator.

[0056] <Control Unit> The control unit 83 is composed of a CPU, ROM, RAM, input / output circuits, etc. The control unit 83 receives the measurement results of the two-dimensional scanner 40 transmitted by the first terminal device 60, and also receives the position and attitude of the cart 10 transmitted by the second terminal device 70. The control unit 83 includes, as functional units, a calibration unit 83b, a transformation matrix generation unit 83c, a coordinate conversion unit 83d, a shape calculation unit 83e, and a shape determination unit 83f.

[0057] ≪Storage section≫ The storage unit 83a stores vehicle body data (for example, CAD data) that is data indicating the shape of the body-in-white 2 in advance.

[0058] ≪Calibration section≫ The calibration unit 83b calculates the coordinates (X, Y, Z) of the origin o of the two-dimensional scanner 40 in the XYZ coordinate system based on the measurement results of the jig 20 by the two-dimensional scanner 40 and the measurement results of the jig 20 by the multiple imaging devices 50. A ,Y A ,Z A ) is calculated.

[0059] In the calibration stage, the operator places the jig 20 at an arbitrary position by moving the support part 5, and changes the posture of the jig 20 multiple times by manipulating the bracket 6. The calibration unit 83b acquires the three-dimensional coordinates in the xyz coordinate system of multiple points P1, P2, and P3 as measurement results by the two-dimensional scanner 40 in each posture, and acquires the three-dimensional coordinates in the XYZ coordinate system of multiple points Q1, Q2, and Q3 as calculation results by the imaging device 50 in each posture. Here, P1 and Q1 are the same point, P2 and Q2 are the same point, and P3 and Q3 are the same point. The calibration unit 83b aligns the xyz coordinate system and the XYZ coordinate system by utilizing the fact that the measurement result P and the calculation result Q in the same posture are the same point. Through this alignment, the calibration unit 83b aligns the coordinates (X A ,Y A ,Z A ) is calculated.

[0060] The calibration unit 83b calculates the coordinates (X A ,Y A ,Z A ) is calculated.

[0061] <Transformation matrix generation section> The transformation matrix generation unit 83c calculates the three-dimensional coordinates (X A ,Y A ,Z A ) and the calculation results (RX, RY, RZ, W, X', Y', Z') of the carriage coordinate calculation unit 53b, a transformation matrix A is generated for each frame. X ,A Y ,A Z ,A S It is expressed by a combination (product) of the above. A X is a transformation matrix related to rotation around the X axis, and is expressed by the following equation. A Y is a transformation matrix related to rotation around the Y axis, and is expressed by the following equation. A Zis a transformation matrix related to rotation around the Z axis, and is expressed by the following equation. A S is a transformation matrix relating to shifts in the X-axis, Y-axis, and Z-axis directions, and is expressed by the following equation.

[0062]

number

[0063] The transformation matrix generation unit 83c generates the transformation matrix A (the transformation matrix A for each frame). f ) to the coordinate conversion unit 83d.

[0064] <Coordinate conversion section> The coordinate conversion unit 83d converts the measurement result of the two-dimensional scanner 40 transmitted by the first terminal device 60 and the transformation matrix A (the transformation matrix A for each frame) output from the transformation matrix generation unit 83c. f ) and by using the transformation matrix A, the measurement results of the two-dimensional scanner 40 are transformed from the xyz coordinate system to the XYZ coordinate system for each frame.

[0065]

number

[0066] The coordinate conversion unit 83d outputs the measurement results of the two-dimensional scanner 40 for each frame, which have been converted into the XYZ coordinate system, to the shape calculation unit 83e.

[0067] Such coordinate conversion by the coordinate conversion unit 83d can correct a change in the posture of the cart 10. For example, when the cart 10 rotates around the Y axis (FIG. 6 → FIG. 7), the coordinate conversion unit 83d can correct the measurement result as if measuring the shape of the body-in-white 2 from the same angle as before the two-dimensional scanner 40 rotated around the Y axis (see FIG. 6) (see FIG. 7).

[0068] ≪Shape calculation section≫ The shape calculation unit 83e acquires the converted measurement results output from the coordinate conversion unit 83d, and calculates three-dimensional coordinates (point cloud data) representing the shape of the body-in-white 2 by combining the acquired converted measurement results with the X coordinate of the bogie 10 corresponding to the measurement results for each synchronized frame. 0th frame: (X0, Y0, Z 0·0 ),(X0,Y1,Z 0·1 ),…,(X0,Y N ,Z 0·N ) 1st frame: (X1,Y0,Z 1·0 ),(X1,Y1,Z 1·1 ),…,(X1,Y N ,Z 1·N ) … F frame: (X F ,Y0,Z F·0 ),(X F ,Y1,Z F·1 ),…,(X F ,Y N ,Z F · N ) Here, the subscript of the X coordinate represents the frame order f (f=0, 1, 2, ..., F). The subscript of the Y coordinate indicates the order n (n=0, 1, 2, . . . , N) of the point cloud data arranged in the Y axis direction. The left side of the Z coordinate subscript represents the frame order f (f=0, 1, 2, ..., F). The right side of the Z coordinate subscript represents the order n (n=0, 1, 2, ..., N) of the point cloud data arranged in the y-axis direction.

[0069] The shape calculation unit 83e outputs the calculated three-dimensional coordinates (point cloud data) representing the shape of the body-in-white 2 to the shape determination unit 83f.

[0070] ≪Shape determination section≫ The shape determination unit 83f determines whether the shape of the body-white 2 is acceptable by comparing the three-dimensional coordinates (point cloud data) representing the shape of the body-white 2 output from the shape calculation unit 83e with the vehicle body data (CAD data) stored in the storage unit 93a. The shape determination unit 83f meshes the point cloud data, projects the meshed point cloud data onto the vehicle body data (CAD data) using a three-point best fit method, and compares them. If there is a deviation of a predetermined value (e.g., 1 mm) or more between the calculated three-dimensional coordinates (point cloud data) and the stored vehicle body data, the shape determination unit 83f determines that the shape of the corresponding part of the body-white 2 is unacceptable. If there is no deviation of a predetermined value (e.g., 1 mm) or more between the calculated three-dimensional coordinates (point cloud data) and the stored vehicle body data, the shape determination unit 83f determines that the body-white 2 is acceptable. The shape determination unit 83f displays the determination result on the display unit 82.

[0071] A shape measurement system 1 according to an embodiment of the present invention comprises one or more two-dimensional scanners 40 that measure two-dimensional shape data of an object being carried on a cart 10, a plurality of imaging devices 50 that capture images of the cart 10, a cart position and orientation calculation unit 73b that calculates the position and orientation of the cart 10 based on the imaging results of the plurality of imaging devices 50, a coordinate conversion unit 83d that converts the two-dimensional shape data from a three-dimensional coordinate system based on the two-dimensional scanner 40 to a three-dimensional coordinate system corresponding to the imaging results of the plurality of imaging devices 50 based on the calculation results of the cart position and orientation calculation unit 73b, and a shape calculation unit 83e that calculates three-dimensional shape data of the object based on the converted two-dimensional shape data and the calculation results of the cart position and orientation calculation unit 73b. Therefore, the shape measurement system 1 measures the three-dimensional shape of the object while correcting lateral deviations relative to the direction of travel of the cart 10 and deviations in the rotational (yaw, pitch, roll) directions of the cart 10, thereby enabling the three-dimensional shape of the object to be measured with high accuracy. Furthermore, the shape measurement system 1 measures the three-dimensional shape of an object being transported by the cart 10, so it is possible to measure the three-dimensional shape of an object in a small space, at low cost, and in a short time.

[0072] In the shape measurement system 1, one or more of the two-dimensional scanners 40 are fixed at positions where they can measure the object that is being carried on the carriage 10. Therefore, the shape measurement system 1 measures the three-dimensional shape of an object by moving the object without moving the two-dimensional scanner 40, thereby improving the freedom of installation of the two-dimensional scanner 40 and enabling high-precision and high-efficiency measurements to be achieved.

[0073] The shape measurement system 1 includes a synchronization device 30 that synchronizes the measurement timing of one or more of the two-dimensional scanners 40 with the image capturing timing of the plurality of image capturing devices 50. Therefore, the shape measurement system 1 can convert the two-dimensional shape data using the position and orientation of the cart 10 at the same time as the two-dimensional shape data, and efficiently calculate three-dimensional shape data of the object. In other words, the shape measurement system 1 can efficiently calculate three-dimensional shape data of the object without performing interpolation of the two-dimensional shape data and / or the position and orientation of the cart 10.

[0074] In the shape measurement system 1, the object is a vehicle body after assembly and before painting. Therefore, the shape measurement system 1 can achieve correction of the vehicle body in a short time and at low cost compared to the case where the shape of the vehicle body is measured and corrected after painting.

[0075] Although the embodiments of the present invention have been described above, the present invention is not limited to the above embodiments and can be modified as appropriate without departing from the spirit and scope of the present invention. For example, the target object is not limited to the body-in-white 2, but may be various objects whose three-dimensional surface shape needs to be measured. Furthermore, the first terminal device 60, the second terminal device 70, and the third terminal device 80 can be replaced with a single terminal device (such as a server) having these functions. Furthermore, the synchronization device 30 may be omitted, and the control unit 83 of the third terminal device 80 may be configured to include an interpolation unit that temporally interpolates at least one of the two-dimensional data and the transformation matrix (or the image data) to synchronize the time of the two-dimensional data and the transformation matrix. [Explanation of symbols]

[0076] 1. Shape measurement system 2. Body in white (vehicle, object) 10 carts 20 Jig 30 Synchronous Device 40 2D scanner 50 Imaging device 60 First terminal device 70 Second terminal device 73b Cart position and attitude calculation unit 80 Third terminal device 83b Calibration section 83c Transformation matrix generator 83d Coordinate conversion section 83e Shape calculation section

Claims

1. one or more two-dimensional scanners that measure two-dimensional shape data of an object being carried on a carriage; a plurality of imaging devices for imaging the dolly; a dolly position and orientation calculation unit that calculates the position and orientation of the dolly based on the imaging results of the plurality of imaging devices; a coordinate conversion unit that converts the two-dimensional shape data from a three-dimensional coordinate system based on the two-dimensional scanner to a three-dimensional coordinate system that corresponds to the imaging results of the plurality of imaging devices, based on the calculation result of the cart position and orientation calculation unit; a shape calculation unit that calculates three-dimensional shape data of the object based on the converted two-dimensional shape data and a calculation result of the carriage position and orientation calculation unit; A shape measurement system comprising:

2. One or more of the two-dimensional scanners are fixed at positions where they can measure the object being carried on the carriage.

2. The shape measurement system according to claim 1.

3. a synchronization device that synchronizes the measurement timing of one or more of the two-dimensional scanners with the image capturing timing of the plurality of image capturing devices; 2. The shape measurement system according to claim 1.

4. The object is a vehicle body after assembly and before painting.

2. The shape measurement system according to claim 1.

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