JPH0755439A - Three-dimensional shape measuring equipment - Google Patents

Abstract

PURPOSE:To provide a three-dimensional shape measuring equipment in which automatic tracking operation is enabled even when the tracking distance of a spot image is long. CONSTITUTION:Rough distance between a laser pointer 1 and a spot image 5 can be operated based on the moving amount of focus lens 6 in the laser pointer 1 when a spot light therefrom is focused, as a spot image 5, at a required position of an object 4. Rough three-dimensional coordinate position of the spot image 5 is then operated based on the rough distance and the spot light projecting angle of the laser pointer 1. A laser tracker 2 is controlled based on the data of rough three-dimensional coordinate position to track the spot image 5 thus allowing automatic tracking of the spot image 5 even when the moving distance of the spot image 5 is long to cause deviation thereof from the image of the laser tracker 2.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a three-dimensional shape measuring apparatus using a spot light projection method, and more particularly, it has been improved so that the spot light projected on an object to be measured can be easily tracked. And a three-dimensional shape measuring device.

[0002]

2. Description of the Related Art A three-dimensional shape measuring apparatus using a spot light projection method is known as a non-contact apparatus for measuring a three-dimensional shape of an object to be measured. This three-dimensional shape measuring device projects a spot light onto a desired position of an object to be measured and measures the three-dimensional position onto which the spot light is projected according to the principle of triangulation to obtain the three-dimensional shape of the object to be measured. Can be measured. The conventional configuration of the three-dimensional shape measuring apparatus will be described below with reference to FIG. In FIG. 3, a three-dimensional shape measuring apparatus 51 having a conventional configuration includes a laser pointer 54 that projects a spot light 53 of a laser beam onto an object to be measured 52 and a spot image 55 projected on the object to be measured 52. A laser tracker 56 for imaging and a control device 58 for calculating the three-dimensional position of the object from the data obtained by controlling the laser pointer 54 and the laser tracker 56 are provided. The laser pointer 54 is an electronic theodolite equipped with a spot light projector, and the laser tracker 56 is also an electronic theodolite equipped with a TV camera. Has been done. Further, the control device 58 controls the laser pointer 54 and the electronic theodolite of the laser tracker 56 to operate each optical axis, and the image processing device 5 which detects the spot image obtained from the laser tracker 56.
7 and a computer 59 that controls these and performs measurement calculation
And is configured. In the above configuration, the laser pointer 54 projects the spot light 53 to form a spot image 55 on the object to be measured 52.
The image is taken with the TV camera of No. 6, and the control device 58 is taken from this image.
The image processing device 57 detects the position of the spot image 55 on the screen. The computer 59 is the image processing device 57.
The directional angle of the spot image 55 seen from the laser tracker 56 is calculated from the detection result of ## EQU1 ## The three-dimensional position of the spot image 55 on the object to be measured 52 can be obtained from the positional relationship of 1 by the principle of triangulation. Therefore, the data of the direction angle at which the laser pointer 54 projects the spot light 53, and the laser tracker 56 displays the spot image 55.
By providing a computer with a procedure for automatically tracking, the three-dimensional coordinates within a fixed area of the object to be measured 52 can be automatically measured throughout, and the shape of the object to be measured 52 is measured. .

[0003]

In the above conventional configuration, the procedure for the laser tracker to automatically track the spot image is executed as shown in the flowchart of FIG. In this spot image tracking procedure, when the laser tracker cannot detect the spot image (step 3 in the procedure shown in FIG. 4), the moving direction of the laser tracker is set to T.
It becomes impossible to know from the V image. At this time, the movement of the laser tracker (step 4 of the procedure shown in FIG. 4) is designated by the operator. However, since it is difficult for the operator to specify the tracking direction of the spot image, it is easy to make a mistake in the specified direction, and as a result, there is a problem that tracking fails and it takes time to correct the direction. The present invention was devised in view of the above problems, and an object of the present invention is to provide a three-dimensional shape measuring apparatus capable of automatic tracking operation even when the tracking distance of a spot image is large.

[0004]

In order to achieve the above object, the means adopted by the present invention are a spot light source for projecting spot light on an object to be measured, and a light source drive for changing the projection angle of the spot light source. A mechanism, an image pickup device arranged at a predetermined distance from the spot light source for picking up a spot image formed by the spotlight on the object to be measured, and an image pickup device drive mechanism for changing an image pickup angle of the image pickup device. Then
The position coordinates of the spot image projected on the object to be measured are calculated from the projection angle of the spot light source, the imaging angle of the imaging device, and the distance between the spot light source and the imaging device by the principle of triangulation. A detecting means for detecting a controlled variable of a focusing mechanism provided in the spot light source, in a three-dimensional shape measuring device for measuring a three-dimensional shape of an object to be measured by sequentially moving the projection position of the spot light; ，
Calculation means for calculating the approximate three-dimensional coordinate position of the spot image on the object to be measured from the detection value by the detection means and the projection angle of the spot light by the light source drive mechanism, and the focusing mechanism provided in the imaging device. Focusing mechanism drive means for controlling the image pickup device, and control for controlling the image pickup device drive mechanism and the focusing mechanism drive means based on the output from the calculation means so that the image pickup device tracks a spot image on the object to be measured. It is configured as a three-dimensional position shape measuring apparatus characterized by comprising:

[0005]

According to the present invention, when the spot light projected from the spot light source is imaged as a spot image at a desired position on the object to be measured, the spot light source and the object to be measured can be determined from the control amount of the focusing mechanism of the spot light source. The approximate distance to the spot image on the object can be calculated. Therefore, the approximate three-dimensional coordinate position of the spot image is calculated from the spot light projection angle of the spot light source by the light source driving mechanism and the approximate distance between the calculated spot light source and the spot image on the object to be measured. It If the focusing mechanism driving means and the imaging device driving mechanism are controlled by the calculated data of the approximate three-dimensional coordinate position of the spot image, the imaging device is moved in the direction for tracking the spot image by the imaging device driving mechanism. The spot image that is almost focused by the focusing mechanism driving means is captured on the image. Therefore, even if the spot image is moved a long distance by the spot light source and the spot image deviates from the image of the image pickup device, the spot image is automatically tracked without relying on the tracking operation by the operator.

[0006]

Embodiments of the present invention will be described below with reference to the accompanying drawings for the understanding of the present invention. The following embodiments are examples of embodying the present invention and do not limit the technical scope of the present invention. 1 is a schematic diagram showing the configuration of a three-dimensional shape measuring apparatus according to the first embodiment of the present invention, and FIG. 2 is a schematic diagram showing the configuration of a three-dimensional shape measuring apparatus according to the second embodiment of the present invention. Is. In Figure 1,
The three-dimensional shape measuring apparatus 20 according to the first embodiment is configured to include a laser pointer 1, a laser tracker 2, and a control device 3. The laser pointer 1 is
A spot light source 7 for projecting spot light by a laser beam and a light source driving mechanism 8 for driving the spot light source 7 to move the projection direction of the spot light in an arbitrary direction are provided. Driving mechanism (not shown) of the light source focusing lens 6 for adjusting the focal length of the light source lens, and a light source lens moving amount detector (light source lens moving amount detecting means-not shown) for detecting a moving amount of the focusing lens 6 by the driving mechanism. ) And are provided. The laser tracker 2 includes a TV camera (imaging device) 9 and a camera driving mechanism (imaging device driving mechanism) 15 that moves the imaging direction of the TV camera 9 in an arbitrary direction. A driving mechanism (focusing mechanism driving means-not shown) for the camera focusing lens 16 for adjusting the focal length of the captured image is provided. Further, the control device (control means) 3 includes a projection angle control unit 10 for driving and controlling the light source driving mechanism 8, a light source lens control unit 18 for driving and controlling the driving mechanism of the light source focusing lens, and the camera. An imaging angle control unit 17 that drives and controls the drive mechanism 15, and a camera lens control unit 19 that drives and controls the drive mechanism of the imaging focusing lens.
And an image processing unit 11 that processes the image captured by the TV camera 9 and a three-dimensional position shape calculation using each input data, and the control data or operator 13 associated with the calculation is operated from the operation unit. A computer 12 that outputs drive data to each of the control units 10, 17, 18, and 19 based on input input data is provided.

A procedure for measuring a three-dimensional shape using the three-dimensional shape measuring apparatus 20 having the above structure will be described below in order. (1) When the operator 13 inputs measurement point designation data from the operation unit, drive data is input from the computer 12 to the light projection angle control unit 10, and the light projection angle control unit 10 drives the light source drive mechanism 8 by a driving amount. Is output. The light source drive mechanism 8 changes the light projection angle of the spot light source 7 based on this driving amount, so that the laser beam from the spot light source 7 is projected to a desired measurement point on the DUT 4. At this time, the operator 13 performs a focusing operation of the spot image 5 projected on the desired measurement point. This operation is performed by driving the light source focusing lens 6 according to the control amount output from the light source lens control unit 18. (2) The direction data of the spot light source 7 and the position data of the focusing lens 6 when the spot light is projected to a desired measurement point are transmitted to a computer via a projection angle control unit 10 and a light source lens control unit 18, respectively. Take in 12. (3) The computer 12 uses the captured spot light source 7
The approximate three-dimensional coordinate position of the spot image 5 is calculated from the direction data of 1 and the position data of the focusing lens 6.
This calculation is performed by preparing a relational expression using known focal length data of the light source focusing lens 6 in the computer 12. (4) The value calculated by the computer 12 is output to the imaging angle control unit 17 and the camera lens control unit 19.
The imaging angle control unit 17 outputs the drive amount of the camera drive mechanism 15 to move the TV camera 9 in the spot image 5 direction.
Further, the camera lens controller 19 outputs the driving amount of the camera lens driving mechanism to focus an image. (5) With the above operation, the spot image 5 is displayed on the TV camera 9
Is well within the field of view, and the image is in focus. The image of the spot image 5 is captured by the image processing unit 11. (6) The image processing unit 11 obtains the image coordinates of the spot image 5 on the captured image. (7) The computer 12 calculates the direction of the spot image 5 from the image coordinate value and the value of the imaging direction. (8) The coordinate position of the spot image 5 is calculated based on the preset distance between the laser pointer 1 and the laser tracker 2 and the calculated value according to (7).

In the above series of procedures, the operator 1
It is only necessary to specify the measurement point in item (1), which requires the operation in step 3. After that, the laser tracker 2 automatically tracks the spot image 5, and the three-dimensional coordinates of the position of the spot image 5 are calculated each time. Therefore, even if the position of the spot image 5 is largely apart from the viewing angle of the laser tracker 2, automatic tracking is performed, so that the operator 13 determines the projection position of the spot light without paying attention to the posture of the laser tracker 2. be able to. Next, a second embodiment of the present invention will be described. In this embodiment, the laser pointer 1 and the laser tracker 2 in the first embodiment are coaxially and integrally formed, and a three-dimensional shape measuring apparatus is used. In FIG. 2, the three-dimensional shape measuring apparatus 37 is provided with a spot light source 21 that projects a spot light and an optical axis of the spot light from the spot light source 21 that is orthogonal to the optical axis of the spot light. A projecting mirror 25, which is rotatably mounted as a center, reflects the spot light projected from the spot light source 21 and projects the spot light onto an object 35 to be measured, and the projecting mirror 25 with the spot light source 21 interposed therebetween. And the spot light source 21 are provided integrally with the light receiving mirror 28, which is provided in the opposite direction to the light receiving mirror 28 and is rotatably mounted about an axis parallel to and integrally formed with the axis of the light projecting mirror 25. An image pickup unit 22 having an image pickup element 26 for picking up a spot image 36 on the object 35 to be measured reflected by the light receiving mirror 29 and detecting the position of the spot image 36 picked up. The light projecting mirror 25 is rotated to project spot light on the object 35 to be measured, and the spot image 36 projected on the object 35 to be measured is rotated on the light receiving mirror 28 to be imaged on the image pickup device 26. From the rotation angle of the light projecting mirror 25, the rotation angle of the light receiving mirror 28 and the distance between the axis of the light projecting mirror 25 and the axis of the light receiving mirror 28 when the image forming point reaches a predetermined position, The calculation CPU 32 for calculating the position coordinates of the spot image on the DUT 35 is provided. In the above configuration, the spot light source 21 has a light source focusing lens 24, and the imaging unit 22 has an imaging focusing lens 27.
And a lens drive mechanism (not shown) are provided. Further, the light projecting mirror 25 and the light receiving mirror 28 are provided with a mirror driving mechanism (not shown). Further, the projecting mirror 25 and the receiving mirror 28
An encoder (not shown) for detecting each rotation angle, an unillustrated encoder for detecting each lens position of the light source focusing lens 24 and the imaging focusing lens 27, and the rotation drive mechanism 2
The encoder 9 is provided with an encoder (not shown) that detects the rotation angle of the rotation drive mechanism 29.

The light projecting / receiving device having the above-mentioned structure is disposed in the upper structure 30, and the upper structure 30 is rotatably supported by the rotation drive mechanism 29 on the support structure 31.
Further, each drive mechanism is configured to be controlled by a drive control unit 33 which outputs a drive signal based on a control signal from the arithmetic CPU unit 32. A procedure for measuring a three-dimensional shape using the three-dimensional shape measuring device 37 having the above configuration will be described below in order. (1) By the operator inputting measurement point designation data from the operation unit 23 attached to the arithmetic CPU unit 32,
Drive data is input to the drive control unit 33 from the arithmetic CPU unit 32, and the drive control unit 33 outputs the drive amount to the rotation drive mechanism 29, the drive mechanism of the projection mirror 25, and the focusing lens drive mechanism of the spot light source 21. Based on this driving amount, the light projecting mirror 25 reflects the spot light from the spot light source 21 toward the object 35 to be measured, so that the spot light is projected to a desired measurement point on the object 35 to be measured. Further, at the same time, the operator can see the spot image 3 projected on the desired measurement point.
6. Focusing operation 6 is performed. This operation is performed by driving the light source focusing lens 24 by the control amount output from the drive control unit 33. (2) When the spot light is projected to a desired measurement point, the calculation CPU unit 32 calculates the projection angle of the spot light from the encoder output of the projection mirror 25. (3) Similarly, the calculation CPU section 32 calculates the distance from the projection mirror 25 to the spot image 36 from the encoder output of the light source focusing lens 24. This calculation is
This is done by preparing in the computer 12 a relational expression using the known focal length data of the light source focusing lens 6. (4) The approximate three-dimensional position coordinates of the spot image 36 are calculated from the calculated projection angle of the spot light and the distance from the projection mirror 25 to the spot image 36. (5) From the calculated values of the approximate three-dimensional position coordinates of the spot image 36, the rotation angle of the light receiving mirror 28 and the position of the imaging focusing lens 27 are calculated by a relational expression prepared in advance in the calculation CPU section 32. (6) The calculated value is output to the drive control unit 33, and the drive mechanism of the light receiving mirror 28 and the imaging focusing lens 27 are output.
The light receiving mirror 28 and the imaging focusing lens 27 are driven by the driving mechanism of the above. (7) The image signal from the image sensor 26 is calculated by the arithmetic CPU unit 32.
Is input to, the angle of the light receiving mirror 28 is finely adjusted so that the imaged spot image 36 is formed at a predetermined position on the image pickup element 26. (8) The imaging angle of the spot image 36 is calculated from the encoder output of the light receiving mirror 28. (9) The rotation angle of the upper structure 30 is calculated from the encoder output of the rotary drive mechanism 29. (10) Three-dimensional position coordinates of the spot image 36 are calculated from the imaging angle of the spot image 36, the rotation angle of the upper structure 30, and the rotation center distance between the light projecting mirror 25 and the light receiving mirror 28. . In the above series of procedures, the operator only needs to specify the measurement points in (1). After that, the spot image 36 is automatically tracked, and calculation of three-dimensional position coordinates is automatically executed. As shown in the first and second embodiments, the three-dimensional position coordinates of the spot image formed by projecting the spot light at a desired position on the object to be measured are automatically calculated. The three-dimensional position of the object to be measured can be measured by forming spot images at a plurality of positions on the object to be measured and determining the position coordinates for each.

[0010]

As described above, according to the present invention, the spot image formed at the desired position on the object to be measured is automatically tracked, so that the conventional apparatus does not appear on the image on the imaging side. Even if a large spot image moves, it can be easily tracked. Therefore, it is possible to provide the three-dimensional shape measuring apparatus in which the work that requires skill in the operation of tracking the spot image in the conventional three-dimensional position measurement is automated.

[Brief description of drawings]

FIG. 1 is a schematic diagram showing a configuration of a three-dimensional shape measuring apparatus according to a first embodiment of the present invention.

FIG. 2 is a schematic diagram showing a configuration of a three-dimensional shape measuring apparatus according to a second embodiment of the present invention.

FIG. 3 is a schematic diagram showing a configuration of a three-dimensional shape measuring apparatus according to a conventional example.

FIG. 4 is a flowchart showing a measurement procedure by a three-dimensional shape measuring apparatus according to a conventional example.

[Explanation of symbols]

 1 ... Laser pointer 2 ... Laser tracker 3 ... Control device (control means) 4, 35 ... Object to be measured 5, 36 ... Spot image 6, 24 ... Light source focusing lens 7, 21 ... Spot light source 8 ... Light source drive mechanism 9 ... TV Camera 10 ... Light source angle control section (control means) 15 ... Camera drive mechanism 16 ... Camera focusing lens 17 ... Imaging angle control section (control means) 18 ... Light source lens control section (control means) 19 ... Camera lens control section (control means) ) 20, 37 ... Three-dimensional shape measuring device 22 ... Imaging unit (camera) 25 ... Projection mirror (light source drive mechanism) 27 ... Imaging focusing lens 28 ... Receiving mirror (camera drive mechanism) 29 ... Rotation drive mechanism (light source and camera) Drive mechanism) 32 ... Arithmetic CPU section (control means) 33 ... Drive control section (control means)

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁶ Identification number Internal reference number FI Technical display location G06T 7/00 (72) Inventor Satoshi Yamazaki 1-5-5 Takatsukadai, Nishi-ku, Kobe-shi, Hyogo Stock Company Kobe Steel Works, Kobe Research Institute (72) Inventor Taizo Yoshida 4-5-22 Iwayakitamachi, Nada-ku, Kobe-shi, Hyogo Inside Shinko Plant Construction Co., Ltd.

Claims (1)

[Claims] 1. A spot light source for projecting a spot light onto an object to be measured, a light source driving mechanism for changing a projection angle of the spot light source, and a spot light source arranged on the object to be measured at a predetermined distance. An image pickup device for picking up a spot image formed by spotlight, and an image pickup device drive mechanism for changing an image pickup angle of the image pickup device, wherein a projection angle of the spot light source, an image pickup angle of the image pickup device, The position coordinates of the spot image projected on the object to be measured are calculated from the distance between the spot light source and the image pickup device by the principle of triangulation, and the object to be measured is moved by sequentially moving the projected position of the spot light. In the three-dimensional shape measuring device for measuring the three-dimensional shape, the detection means for detecting the control amount of the focusing mechanism provided in the spot light source, the detection value by the detection means, and Computing means for computing the approximate three-dimensional coordinate position of the spot image on the object to be measured from the projection angle of the spot light by the light source driving mechanism, and focusing mechanism driving means for controlling the focusing mechanism provided in the imaging device. A control means for controlling the image pickup device drive mechanism and the focusing mechanism drive means based on the output from the calculation means so that the image pickup device tracks a spot image on an object to be measured. A three-dimensional shape measuring device.