JPH06331326A - Three-dimensional shape measuring apparatus - Google Patents

Abstract

PURPOSE:To measure a three-dimensional shape even when a large object to be measured is vibrated by constituting an imaging means of a polyhedral split type optical sensor equipped with a plurality of imaging surfaces outputting the electric signals corresponding to the intensities of the spot images caught by the respective imaging surfaces. CONSTITUTION:A second theodolite 15 is constituted of a polyhedral split type optical sensor 14 having a plurality of imaging surfaces corresponding to the image receiving areas of the spot images caught by the respective imaging surfaces. The spot images on the image receiving surfaces are moved by a second drive part 18 and the spot lights 10 applied to a vibrated object 2 to be measured are imaged by the optical sensor 14 and the difference signal of the output signals from the respective imaging surfaces is detected and the position coordinates of the spot lights are operated on the basis of the imaging angle of the second theodolite 15 wherein the difference signal attains a predetermined balance state. By this constitution, even in such a state that the object 2 to be measured is vibrated, the position coordinates of the spot lights can be operated on the basis of an imaging angle wherein the different signal attains a predetermined balance state.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to improvement of a three-dimensional shape measuring device, and more particularly, to the shape of a large object to be measured such as a building structure, car body, hull, pressure vessel, etc. The present invention relates to a three-dimensional shape measuring device capable of simply measuring high precision and high speed.

[0002]

2. Description of the Related Art Conventionally, various measuring methods such as an AM optical phase difference measuring method and a spot light projecting method have been proposed as a method for measuring a three-dimensional shape of an object to be measured without contact. Of which
The spot light projection method, which projects the spot light onto the non-measurement object, uses the principle of triangulation, and is generally known to be highly reliable and highly accurate. FIG. 7 shows an example of a three-dimensional shape measuring apparatus using the spot light projection method. The three-dimensional shape measuring apparatus 51 includes a theodolite 54 that projects a laser beam 53 on the object to be measured 52 with a variable projection angle, and a TV camera 56 that images the spot light 55 projected on the object to be measured 52.
It has and. The theodolite 54 and the TV camera 56 are arranged at a predetermined distance (for example, L) from each other as schematically shown in FIG. The theodolite 54
The spot light 55 formed by the laser beam 53 emitted from the TV camera 56 is imaged by the TV camera 56, and the TV camera 56 is rotationally controlled so as to come to a predetermined point (for example, the center point) of the TV camera 56, and the spot is spotted. The light 55 is tracked. In this three-dimensional shape measuring device 51, the image processing device 57 is used to perform image processing in real time in order to increase the rotation control speed. Then, the projection angle of the laser light 53 when the imaged spot image reaches the center point of the TV camera 56 (eg, θ 1 and φ 1 shown in FIG. 8),
The angle of the spot image captured by the TV camera 56 (θ2, φ2 in the figure), and the position of the spot light 55 on the DUT 52 whose origin is the midpoint 58 of the same distance L from the value of the distance L. Coordinates (X, Y, Z) are obtained based on the principle of triangulation, for example, according to the following equation, and the three-dimensional shape of the measured object 52 is measured. X = L (tan θ2 + tan θ
1) / 2 (tan θ2 −tan θ1) Y = Ltan θ2 tan θ1 / (tan θ2 −tan θ1) Z = Ltan θ2 tan θ1 tan φ1 / tan θ2 −tan θ1)
sin θ1 = Ltan θ2 tan θ1 tan φ2 / (tan θ2 −tan
θ1) sin θ2 In order to improve the accuracy and speed of such a three-dimensional shape measuring apparatus, the applicant of the present application has disclosed in Japanese Unexamined Patent Publication No. 3-2 shown in FIG.
The conventional technique disclosed in Japanese Patent No. 26615 is being developed. This three-dimensional shape measuring apparatus is a theodolite 6 for light projection, which projects a laser light 61 on a measured object 52 with a variable projection angle.
2 and the spot light 63 projected on the DUT 52.
The theodolites 62 and 64 for image reception for tracking and receiving the images are provided.
It is arranged at a predetermined distance L of m. Both theodolites 62, 64 are provided with encoders 65, 66 for reading the optical axis angles thereof.
Detection signal is input to the CPU 70. CPU70
Are the theodolites 6 based on the input detection signal.
The shape of the object to be measured 52 is measured by sampling the optical axis angles of 2, 64 and calculating the three-dimensional coordinate value of the spot light 63 on the object to be measured 52.
A light source 68 and a lens system 69 are built in the above-mentioned theodolite 62 for projecting light, and an output beam from the light source 68 is focused by the lens system 69 and projected as spot light 63 on the object to be measured 52. . On the other hand, the theodolite 64 for image reception has a four-division optical sensor 73 having a four-division image receiving surface.
And a lens system 74 are built in, and a detection signal on each image receiving surface of the four-division optical sensor 73 is output to the image position detecting section 71. As shown in FIG. 10, each image receiving surface a, b, c, d of the four-division optical sensor 73 is divided into four by two straight lines passing through the center of the four-division optical sensor 73 in both X-axis and Y-axis directions. The intensity of the incident light on each image receiving surface a, b, c, d can be individually detected. The detection signals of the image receiving surfaces a to d are amplified by the operational amplifiers 76 and 77 of the image position detection unit 75, and the outputs of both operational amplifiers 76 and 77 are the operational amplifier 78 for generating the sum signal and the operation for generating the difference signal. It is input to the amplifier 79. The operational amplifier 78 for generating the sum signal generates a sum signal by adding the outputs from all the image receiving surfaces a to d,
In the operational amplifier 79 for generating the difference signal, each image receiving surface a,
A difference signal between the output sum signal of b and the output sum signal of each of the image receiving surfaces c and d is generated. In such a three-dimensional shape measuring apparatus, the theodolite 64 for receiving the image is the spot light 63.
11A, each image-receiving surface a is tracked as shown in FIG.
The spot image 80 of the spot light 63 is moved from the position 81 to the position 82 on the upper part of FIG. At this time, as shown in FIG. 11B, the output signal V of the sum signal V1 and the difference signal V2 of the image position detector 71 changes with respect to the rotation angle θ of the image receiving theodolite 64. The output signal V of the sum signal V1 becomes substantially constant when the spot image 80 moves on each of the image receiving surfaces a to d, and the light receiving state of the spot image 80 is detected by the sum signal V1. On the other hand, the difference signal V2 indicates that the spot image 80 has a four-division optical sensor 73.
When located at the center of, the difference signal V2 becomes zero. Due to such a change in the difference signal V2, a one-dimensional displacement between the optical axis of the theodolite 64 and the projection position of the spot light 63 on the object to be measured 52 is detected. Therefore, the difference signal V2 from the image position detector 71 is input to the encoder 66, and the optical axis angle of the theodolite 64 is adjusted so that the difference signal V2 becomes zero. The three-dimensional shape of the object 52 is measured.

[0003]

In the prior art of the three-dimensional shape measuring apparatus shown in FIG. 9, the three-dimensional shape of the object to be measured 52 can be measured at high speed and with high accuracy.
It is not possible to measure a three-dimensional shape when the is vibrating. The reason is that in the above-mentioned conventional technique, the optical axis angle is controlled by the optical axis angle control system including the four-division optical sensor 73, the image position detector 71, and the encoder 66 so that the optical axis of the theodolite 64 coincides with the spot light 63. Although it is necessary, when the DUT 52 is vibrating, the above 4
The spot image 8 is formed on each of the image receiving surfaces a to d of the split optical sensor 73.
This is because 0 moves and the position of the spot image 80 changes, so that the optical axis angle cannot be normally controlled. For example, when the vibration frequency of the object to be measured 52 is lower than the response frequency of the optical axis control system, the optical axis of the theodolite 64 vibrates following the position change due to the vibration of the spot light 63. On the other hand, when the vibration frequency of the DUT 52 is higher than the response frequency of the optical axis control system,
The optical axis of the theodolite 64 cannot track the position of the spot light 63. As described above, in any case, when the DUT 52 is vibrating, the position of the spot light 63 cannot be calculated, and the three-dimensional shape measurement based on the above-described triangulation principle is impossible. There is a problem that becomes. In order to solve the problems in the conventional technique, the present invention can measure a three-dimensional shape even when a large object to be measured such as a building structure or a vehicle body is vibrating. The purpose of the present invention is to provide a shape measuring device.

[0004]

In order to achieve the above object, the present invention detects a light projecting means for projecting a spot light onto an object to be measured with a variable light projecting angle, and detecting the light projecting angle of the spot light. Projection angle detection means, imaging means arranged at a predetermined distance from the projection means, for imaging the spot image projected on the object to be measured, and the imaging means for rotating the imaging means. An image moving means for moving the imaged spot image, and an imaging angle detecting means for detecting a rotation amount of the imaging means to detect an imaging angle of the spot image are provided. The spot image is moved to a predetermined position of the image pickup means, at which time the light projection angle of the spot light detected by the light projection angle detection means, the image pickup angle of the spot image detected by the image pickup angle detection means, and the light projection means Imaging above In a three-dimensional shape measuring apparatus for calculating the position coordinates of spot light on an object to be measured from the value of the distance from the step, an electric signal corresponding to the intensity of the spot image captured by each of the image capturing means on each image capturing surface. A multi-faceted optical sensor having a plurality of image pickup surfaces for outputting, and moving the spot image by the image moving means, and causing the spot light on the vibrating object to be measured to be the multi-faceted optical sensor. And detecting the difference signal of the output signals from the respective image pickup surfaces, and calculating the position coordinates of the spot light based on the image pickup angle at which the difference signal is in a predetermined balanced state. It is configured as a three-dimensional shape measuring device. The predetermined balance state can be understood as a state in which the DC component of the difference signal of the spot image detection signal is zero. The predetermined balance state can be understood as a state in which the ratio of the time when the voltage of the difference signal becomes a positive voltage and the time when the voltage of the difference signal becomes a negative voltage in one cycle of the vibration of the measured object becomes constant. Further, the predetermined balance state can be understood as a state in which the amplitude ratio becomes constant when the voltage of the difference signal oscillates in both the positive and negative directions due to the vibration of the measured object.

[0005]

According to the present invention, the image pickup means is composed of a multi-plane split type optical sensor having a plurality of image pickup surfaces corresponding to the image receiving areas of the spot images captured on the respective image pickup surfaces, and the image moving means is provided on the image receiving surface. While moving the above spot image in
Imaging means for picking up the vibrating spot light on the object to be measured by the multifaceted optical sensor to detect a difference signal of the output signals from the respective image pickup surfaces, and the difference signal being in a predetermined balance state. Since the position coordinates of the spot light are calculated based on the image pickup angle of, the position coordinates of the spot light are calculated based on the image pickup angle at which the difference signal is in a predetermined balanced state even when the object to be measured is vibrating. It becomes possible to calculate. As a result, even when the measured object is vibrating, the position coordinates of the spot light are calculated, and the three-dimensional shape of the vibrating measured object can be measured. For example, the position coordinate of the spot light on the vibrating object to be measured can be calculated with the state where the DC component of the difference signal of the spot image detection signal becomes zero as the balance state of the difference signal. Also, the ratio of the time when the voltage of the difference signal becomes a positive voltage and the time when the voltage of the difference signal becomes a negative voltage in one cycle of vibration of the DUT vibrates as a balanced state of the difference signal when the ratio is constant. It is also possible to calculate the position coordinates of the spot light on the object. Furthermore, when the voltage of the difference signal oscillates in both the positive and negative directions due to the vibration of the DUT, the position of the spot light on the DUT that vibrates is defined as the state where the amplitude ratio is constant as the balance state of the difference signal. It is possible to calculate the coordinates.

[0006]

Embodiments of the present invention will be described below with reference to the accompanying drawings for the understanding of the present invention. Note that the following embodiments are examples of embodying the present invention and are not of a nature limiting the technical scope of the present invention. 1 is a block diagram showing a schematic configuration of a three-dimensional shape measuring apparatus according to a first embodiment of the present invention, FIG. 2 (A) is a configuration diagram showing an image position detector, and FIG. 2 (B) is a DC component detector. Circuit diagram showing
3A is an explanatory view schematically showing a four-division optical sensor, FIG.
(B) is a graph showing the change of the difference signal due to the vibration of the object to be measured. As shown in FIG. 1, this three-dimensional shape measuring device 1
Is a first theodolite 8 that projects, for example, a laser beam 4 from a light source 3 onto the vibrating DUT 2 through lenses 5, 6 and 7, and spot light projected on the DUT 2. The second theodolite 15 includes a four-division optical sensor 14 that images 10 through the lenses 11, 12, and 13. The control circuit of the three-dimensional shape measuring apparatus 1 is configured with a control unit 16 including a microcomputer CPU or the like as a center, and the control unit 16 includes a first drive unit 17 for rotationally driving the first theodolite 8 and the first drive unit 17. The second drive unit 18 that rotationally drives the 2 theodolite 15, the image position detection unit 19 that processes the output signal from the four-division optical sensor 14, and the four-division optical sensor 14 even when the DUT 2 vibrates. A DC component detector 20 for detecting a predetermined balance state from the difference signal is connected. The first driving unit 17 rotationally drives the first theodolite 8 as shown in FIG. 1, and controls the projection angle (θ1, φ1) of the laser beam 4. The first theodolite 8 and the first drive unit 17, which realize the function of projecting the laser light 4 in a variable projection angle, are an example of a projecting unit. Further, the projection angle (θ1, φ1) of the laser beam 4 is detected by encoders 17a and 17b attached to the motor built in the first driving unit 17, and is input to the control unit 16. The encoders 17a and 17b are an example of the projection angle detection means. The second theodolite 15 is arranged at a predetermined distance (for example, L) from the first theodolite 8, and images the spot light 10 on the image receiving surface of the four-division optical sensor 14 via the lens 11 and the like. The second theodolite 15 is an example of the image pickup means.

The four-division optical sensor 14 is composed of, for example, a silicon photodiode or the like, and as shown in FIG. 3 (A), its light detection surface is divided into four in both the X-axis direction and the Y-axis direction, and four image-receiving surfaces are formed. 14a, 14b, 14c, 14d
Are formed. Therefore, the received light intensity of each image receiving surface can be detected independently. The position of the spot image picked up on the image receiving surface of the four-division optical sensor 14 is determined by the image position detection unit 1 described above.
9 is converted into binary information in the X and Y axis directions (FIG. 3A), and after the influence of the vibration of the DUT 2 included in the binary signal is processed by the DC component detector 20, , Is input to the control unit 16 via the second drive unit 18. The second theodolite 15 is rotationally driven by the second driving unit 18 as shown in FIG. 1, and the position of the spot image picked up on the image receiving surface of the four-division optical sensor 14 is moved. The second drive unit 18 that rotates the second theodolite 15 to move the position of the captured spot image is an example of an image moving unit. The rotation amount of the second theodolite 15 is detected by encoders 18a and 18b attached to a motor built in the second driving unit 18, and an imaging angle of a spot image captured on the image receiving surface of the four-division optical sensor 14. (Θ2, φ2) is detected. Encoders 18a and 18b for detecting the imaging angle (θ2, φ2)
Is an example of the imaging angle detection means. The detection signals of the image receiving surfaces 14a to 14d of the four-division optical sensor 14 are as shown in FIG.
As shown in (A), the operational amplifier 3 of the image position detector 19
Amplified by 0 and 31, the outputs of both operational amplifiers 30 and 31 are input to an operational amplifier 32 for generating a sum signal and an operational amplifier 33 for generating a difference signal. The operational amplifier 32 for generating the sum signal generates a sum signal by adding the outputs from all the image receiving surfaces 14a to 14d, and the operational amplifier 33 for generating the difference signal generates the sum signal output from the image receiving surfaces 14a and 14b. A difference signal from the output sum signals of the image receiving surfaces 14c and 14d is generated. The DC component detector 20 is shown in FIG.
As shown in (B), it is configured as a low-pass filter including resistors 21a, 21b and 21c, capacitors 22a and 22b, and an operational comparator 23, and the DC component detector 20 outputs the image position detector 19 The AC component is removed from the signal, that is, the difference signal, and only the DC component of the difference signal is input to the second drive unit 18.

In this three-dimensional shape measuring apparatus 1, when the laser beam 4 is projected onto the object to be measured 2 by the first theodolite 8, the spot light 10 projected onto the object to be measured 2 is converted into the second theodolite 15. An image is picked up on the image receiving surface of the four-division optical sensor 14 via the lens 11 and the like. Outputs from the image receiving surfaces 14a, 14b, 14c, 14d of the four-division optical sensor 14 even when the image on the image-receiving surface of the four-division optical sensor 14 moves with the vibration of the DUT 2. The second drive unit 18 is drive-controlled so that the signals are in a predetermined balanced state, for example, all become uniform, and the DC component of the difference signal output from the DC component detector 20 becomes zero, and the second theodolite 15 is The orientation of is controlled. While the DUT 2 is vibrating, as shown in FIG. 3A, the spot image 35 of the spot light 10 received on the four-division optical sensor 14 by the lens 11 of the second theodolite 15 or the like.
Moves from the position 36 to the position 37 due to the vibration of the DUT 2. At this time, as shown in FIG. 3B, the difference signal output from the image position detector 19 is synchronized with the vibration of the DUT 2 and is a positive voltage during the time T1 or a negative voltage during the time T2. Wave to. Such an image position detector 1
When the difference signal 9 is input to the DC component detector 20, the DC component detector 20 removes the AC component from the difference signal of the image position detector 19 and inputs only the DC component to the second driver 18. To do. The DC component from the DC component detector 20 is the second drive unit 1.
8 is input to the encoder 18 of the second drive unit 18.
a and 18b are optical axis angles of the second theodolite 15 (θ2,
φ2), the optical axis angle (θ2, φ2) is adjusted so that the output of the DC component detector 20, that is, the DC component of the difference signal becomes zero. By adjusting the optical axis angles (θ2, φ2) of the second theodolite 15 in this way, the DUT 2 vibrates and the difference signal of the image position detection unit 19 synchronizes with the vibration of the DUT 2. Even if it fluctuates, the optical axis angle of the second theodolite 15 (θ
2, φ2) is adjusted and the optical axis angle (θ2, φ2) of the second theodolite 15 is normally controlled even when the DUT 2 is vibrating. As described above, in the three-dimensional shape measuring apparatus 1, even when the DUT 2 is vibrating,
The spot image 35 moves on each of the image receiving surfaces 14a to 14d of the split optical sensor 14 and the position of the spot image 35 changes, so that the optical axis angle (θ2, φ) of the second theodolite 15 changes.
2) There is no risk of becoming uncontrollable, and the optical axis angle (θ2, φ2) of the second theodolite 15 can be controlled so that the optical axis of the second theodolite 15 coincides with the spotlight 10, and the vibration will occur. It becomes possible to measure the three-dimensional shape of the DUT 2 under measurement.

Then, when the DC component of the difference signal output from the DC component detector 20 is in a balanced state in which the DC component is zero, the projection angles (θ1, φ1) of the laser beam 4 detected by the encoders 17a, 17b. ), The imaging angle (θ2, φ2) of the spot light 10 and the above theodolites 8 and 1
From the value of the distance L between the object 5 and the object to be measured 2, the position coordinates (X, Y, Z) of the spot light 10 on the object to be measured 2 are calculated using the above-described formula based on the principle of triangulation. Therefore, the three-dimensional shape of the DUT 2 can be measured even when the DUT 2 is vibrating. Next, a second embodiment of the present invention will be described with reference to FIG. In the second embodiment, the difference signal output from the image position detector 19 is input to the second driver 18 and the time ratio detector 40a, and the object to be measured 2 vibrated by the time ratio detector 40a. The difference signal is processed so that the three-dimensional shape can be measured. The time ratio detector 40a, as shown in FIG.
The comparator 41 to which the difference signal output from 9 is input, and the counters 42 and 43 and the counters 42 and 43 which count according to the positive / negative of the difference signal input to the comparator 41.
Generator 44 for generating the operating reference frequency of
Also, a calculation unit 45 that calculates the time ratio between the positive voltage time and the negative voltage time within one cycle of the vibration of the difference signal based on the output signals from the comparator 41 and the counters 42 and 43.
It is equipped with. As shown in FIG. 3 (B), the difference signal output of the image position detector 19 oscillates into a positive / negative voltage in synchronization with the vibration of the DUT 2, and the comparator 41 indicates that the difference signal is positive. When the voltage is a voltage, the counter 42 is operated, and when the difference signal is a negative voltage, the counter 43 is operated. Both counters 42 and 43 perform counting operation based on the operation reference frequency generated by the clock generator 44, and the frequency is set to a frequency sufficiently higher than the vibration frequency of the DUT 2. Then, the arithmetic unit 45 calculates the ratio of the number of clocks counted by the counters 42 and 43 for each one cycle of the vibration of the DUT 2 in synchronization with the output signal of the comparator 41, and after the calculation, the counters 42. , 43 is returned to zero. Such a time ratio detector 40
In a, the voltage corresponding to the ratio of the time when the difference signal of the image position detection unit 19 which is oscillated in synchronization with the vibration of the DUT 2 is positive and the time when it is negative within one cycle of vibration. From the operation unit 45 to the second drive unit 18 of the second theodolite 15.
Is output to.

In such a three-dimensional shape measuring apparatus 1, when the DUT 2 is stationary, the second theodolite 1 is used.
The second driving unit 18 of No. 5 sets the second theodolite 15 so that the image of the spot light 10 coincides with the center of the four-division optical sensor 14 so that the difference signal of the image position detector 19 becomes zero.
The optical axis angle (θ2, φ2) of is controlled. On the other hand, when the DUT 2 is vibrating, the optical axis angle of the second theodolite 15 is adjusted so that the output of the time ratio detector 19 becomes a predetermined balance state, that is, 1, and the spot light 10
So that the center of vibration of the second theodolite 15 coincides with the center of the image receiving surface of the four-division optical sensor 14 (θ2, φ
2) is controlled. Therefore, even when the DUT 2 is vibrating, it is possible to measure the three-dimensional shape of the DUT 2 without being affected by the vibration, as in the first embodiment. In the second embodiment, the positive / negative time ratio of the voltage of the difference signal is detected irrespective of the magnitude of the difference signal of the image position detector 19, so that the measurement can be performed with a constant sensitivity. . Next, a third embodiment of the present invention will be described with reference to FIG. 4 which is the same as the second embodiment. In this third embodiment,
The difference signal output from the image position detection unit 19 is used as the second drive unit 1.
8 and the amplitude ratio detector 40b, and the difference signal is processed so that the three-dimensional shape of the DUT 2 vibrating by the amplitude ratio detector 40b can be measured. In the amplitude ratio detector 40b, as shown in FIG. 6, the difference signal from the image position detector 19 is a positive voltage detection circuit 46 and a negative voltage detection circuit 47.
And a calculation unit 48. The positive voltage detection circuit 46 is composed of a diode 24 for positive voltage, a capacitor 25 and a resistor 26. Similarly, the negative voltage detection circuit 47 includes a diode 27 for negative voltage and a capacitor 2
8 and a resistor 29. The difference signal output of the image position detector 19 similar to that of the second embodiment is as shown in FIG.
As shown in (B), it oscillates into a positive / negative voltage in synchronism with the vibration of the DUT 2. At this time, the positive / negative detection circuit 4
Reference numerals 6 and 47 detect the difference signal for each of positive and negative voltages, and the calculation unit 48 calculates the output ratio of both detection circuits 46 and 47. Therefore, in the amplitude ratio detector 40b, a voltage corresponding to the amplitude ratio of the positive voltage and the negative voltage of the difference signal of the image position detecting section 14 which changes in synchronization with the vibration of the DUT 2 is output from the calculating section 48. It is output to the second driving unit 18 of the second theodolite 15.

In the three-dimensional shape measuring apparatus 1 as described above, when the object 2 to be measured is stationary as in the second embodiment, the second driving unit 18 of the second theodolite 15 causes the image position to be changed. In order to make the difference signal of the detector 19 zero, the optical axis angle (θ2, φ2) of the second theodolite 15 is controlled so that the image of the spot light 10 coincides with the center of the four-division optical sensor 14. On the other hand, when the DUT 2 is vibrating, the optical axis angle of the second theodolite 15 is adjusted so that the output of the time ratio detector 19 becomes a predetermined balance state, that is, 1, and the spot light 10 Of the second theodolite 1 so that the center of vibration of the same coincides with the center of the image receiving surface of the four-division optical sensor 14.
The optical axis angles (θ2, φ2) of 5 are controlled. Therefore, even when the object to be measured 2 is vibrating, it is possible to measure the three-dimensional shape of the object to be measured 2 without being affected by the vibration, as in the first embodiment. In the third embodiment, the image position detector 14 that changes in proportion to the magnitude of vibration of the DUT 2
Since the amplitude of the difference signal is detected, the spot light 10 does not depend on the way the DUT 2 vibrates intermittently.
It is possible to accurately measure the vibration center position of. The present invention is not limited to the above-described three embodiments and can be variously modified. For example, when each of the image receiving surfaces 14a to 14d of the four-division optical sensor 14 is divided into four in the X-axis and Y-axis directions. Without being limited to this, by dividing into two in one direction of the X-axis direction or the Y-axis direction, the vibration of the spot light 10 on the DUT 2 is replaced by the movement in the one-dimensional direction on the four-division optical sensor 14, The vibration center position of the spot light 10 may be measured.

[0012]

As described above, the three-dimensional shape measuring apparatus according to the present invention is a multifaceted optical system having a plurality of image pickup surfaces corresponding to the image receiving area of the spot image captured by the image pickup means on each image pickup surface. The spot image on the object to be measured is imaged by the multifaceted optical sensor while moving the spot image on the image receiving surface by the image moving means, and is imaged from each of the image pickup surfaces. Is detected, and the position coordinate of the spot light is calculated on the basis of the image pickup angle of the image pickup means that brings the difference signal into a predetermined balanced state. With respect to the position coordinates of the upper spot light, the position coordinates of the spot light can be calculated based on the imaging angle at which the difference signal is in a predetermined balanced state. As a result, even when the DUT is vibrating, the position coordinates of the spot light are calculated without being affected by the vibration, and the vibrating DUT 3
The dimensional shape measurement is performed as in the case of a stationary object. Therefore, even when a large object to be measured such as a building structure is vibrating, its three-dimensional shape can be measured.

[Brief description of drawings]

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

FIG. 2A is a block diagram showing a schematic configuration of an image position detection unit, and FIG. 2B is a block diagram showing a schematic configuration of a DC component detector.

FIG. 3 (A) is a configuration diagram showing movement of an image on a 4-division image receiving surface of a 4-division optical sensor, and FIG. 3 (B) is a graph showing a change in difference signal output with respect to time.

FIG. 4 is a block diagram showing a schematic configuration of a three-dimensional shape measuring apparatus according to second and third embodiments of the present invention.

FIG. 5 is a block diagram showing a schematic configuration of a time ratio detector according to a second embodiment of the present invention.

FIG. 6 is a block diagram showing a schematic configuration of an amplitude ratio detector according to a third embodiment of the present invention.

FIG. 7 is a block diagram showing an example of a conventional three-dimensional shape measuring apparatus using a spot light projection method.

FIG. 8: Theodolite and TV of the same three-dimensional shape measuring device
Explanatory schematic diagram which shows the positional relationship of a camera etc.

FIG. 9 is a block diagram showing a schematic configuration of a conventional three-dimensional shape measuring apparatus that improves accuracy and speed of three-dimensional shape measurement.

FIG. 10 is a block diagram showing a schematic configuration of an image position detection unit in the same three-dimensional shape measuring apparatus.

11A is a configuration diagram showing movement of an image on a 4-division image receiving surface of a 4-division optical sensor, and FIG. 11B is an output signal of the 4-division optical sensor with respect to a rotation angle of an image receiving theodolite. The graph which shows the fluctuation of.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... Three-dimensional shape measuring device 2 ... Object to be measured 4 ... Laser light 8 ... 1st theodolite (a part of light projecting means) 10 ... Spot light 14 ... 4 division | segmentation optical sensor 15 ... 2nd theodolite (imaging means) 16 ... Control unit 17a, 17b ... Encoder (projection angle detection unit) 18 ... Second drive unit (image moving unit) 18a, 18b ... Encoder (imaging angle detection unit) 19 ... Image position detection unit 35 ... Spot image 20 ... DC component Detector 40a ... Time ratio detector 40b ... Amplitude ratio detector

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Sato Yamaguchi 1-5-5 Takatsukadai, Nishi-ku, Kobe City, Hyogo Prefecture Kobe Steel Co., Ltd., Kobe Research Institute (72) Inventor Taizo Yoshida, Nada-ku, Kobe City, Hyogo Prefecture Iwayakitamachi 4-5-22 Shinko Plant Construction Co., Ltd.

Claims (4)

[Claims] 1. A light projecting means for projecting a spot light onto an object to be measured with a variable light projecting angle, a light projecting angle detecting means for detecting a projecting angle of the spot light, and a predetermined device for the light projecting means. Image pickup means arranged to be spaced apart from each other, for picking up a spot image projected on the object to be measured, image moving means for rotating the image pickup means to move the spot image picked up by the image pickup means, and the image pickup Image pickup angle detecting means for detecting the rotation amount of the means and detecting the image pickup angle of the spot image, and moving the spot image picked up by the image pickup means by the image moving means to a predetermined position of the image pickup means, On the object to be measured from the projection angle of the spot light detected by the projection angle detection means, the imaging angle of the spot image detected by the imaging angle detection means, and the value of the distance between the projection means and the imaging means. The spot of light In a three-dimensional shape measuring device for calculating a positional coordinate, the image pickup means is composed of a multi-faceted optical sensor having a plurality of image pickup surfaces for outputting an electric signal according to the intensity of the spot image captured on each image pickup surface. Then, the spot image is moved by the image moving means, and the vibrating spot light on the object to be measured is imaged by the multi-faceted split type optical sensor to detect the difference signal of the output signals from the respective image pickup surfaces. Then, the three-dimensional shape measuring apparatus is characterized in that the position coordinates of the spot light are calculated based on the imaging angle at which the difference signal is in a predetermined balanced state. 2. The three-dimensional shape measuring apparatus according to claim 1, wherein the predetermined balance state is a state in which the DC component of the difference signal of the spot image detection signals is zero. 3. The predetermined balance state is a state in which a ratio of a time when the voltage of the difference signal is a positive voltage and a time when the voltage of the difference signal is a negative voltage in one cycle of vibration of the DUT is constant. Item 3. The three-dimensional shape measuring apparatus according to item 1. 4. The three-dimensional structure according to claim 1, wherein the predetermined balance state is a state in which the amplitude ratio is constant when the voltage of the difference signal oscillates in both positive and negative directions due to the vibration of the object to be measured. Shape measuring device.