JPH09287927A - Projecting-point moving type range finder - Google Patents

Abstract

PROBLEM TO BE SOLVED: To measure the range data of a work without shadow part with high accuracy in a short time. SOLUTION: An image pickup holder 11 having the image pickup system of a lens 9 and a CCD 10 is supported by a fixing case 13 and a rotary stage 15 is supported by the fixing case 13 in such a way that they can be rotated about a central axis 29, respectively. A galvanmo-mirror 20 having a projecting point 32 is provided at the rotary stage 15, and the structuring light is scanned and projected on a work. The projected image reflected from the work is inputted into the CCD 10 separated by a center distance (m). The rotary stage 15 is rotated in the direction where the magnitude of the shadow by the scanning projection becomes minimum through an optical encoder 24 for detecting the rotating angle. The range-image data are composited by the structuring light, which is sequentially projected from the projecting point 32 at the arbitrarily specified angle. The range-image wherein the shadow part becomes minimum, is obtained by a triangulation method.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a projection point moving type range finder (three-dimensional shape measuring apparatus), and more specifically, it is mounted on the tip of an industrial robot, or
It is a measuring device that is fixed at an arbitrary position and measures the three-dimensional shape of a known object, and can be suitably used for a three-dimensional shape input device (three-dimensional digitizer).

[0002]

2. Description of the Related Art A recognition function for recognizing a three-dimensional shape is indispensable for an intelligent robot such as an industrial robot, a robot for ultimate work, or a surveillance robot. It depends. A distance image obtained by measuring a three-dimensional position on the object surface is basically used as a means for recognizing a three-dimensional shape, and a distance image is measured from a point of time when a laser light pulse is emitted. There is a light propagation time method such as obtaining from the time until the light is received or the phase difference between the projected light and the reflected light of the modulated laser beam. However, the optical propagation time method has a characteristic that the measurement accuracy is constant, but it has a problem that the device is complicated and the measurement time is long. Therefore, at present, the method based on triangulation between the projected light and the observed image is often used. Has been.

The method based on the triangulation method scans (projects) slit light (structured light) onto an object, observes the projected light from different angles, and measures the distance from the position of the slit image by the triangulation method. It seeks an image. As described above, as a conventional technique related to the structure of the three-dimensional shape measuring apparatus that scans and projects the structured light onto the unknowable object to measure the three-dimensional shape of the unknowable object, “distance image input by spatial coding” (electronic IEICE Transactions 1985 / 3.VS.J68-DNO3) and "Measurement time of three-dimensional shape measuring device" (Nikkei Mechanical: 19
94.12.26) and the "three-dimensional information extraction method" described in Japanese Patent Application Laid-Open No. 06-117835.

The above-mentioned "image input by space coding" is to project a binary pattern light in the form of vertical stripes, which has been subjected to alternating binary coding, from a pattern light projector to a suspicious object to make the object space into a thin wedge shape. CCD (charge cvapled Dev), which is a divided pattern light, is formed at a distance d from the pattern light projector.
The image is taken with a camera, and the range image is obtained by the triangulation method by minimizing the coding error at the boundary between the light and dark parts of the pattern light.

On the other hand, in the "measurement time of the three-dimensional shape measuring apparatus", the light emitted from the light source is made into structured light by a cylindrical lens or the like and irradiated onto an object while being scanned by a carbano mirror or the like, and the reflected light is reflected by a CCD or the like. This is a method of detecting a distance direction of an object by triangulation by imaging with a light receiving element, and the light receiving element C of the image input device with respect to the light emission position as in the case of "image input by spatial coding" described above.
The positional relationship of CDs is fixed.

[3] In the three-dimensional information extraction method, a symmetric object is placed on a turntable and rotated, and a plurality of images are processed by photographing with a TV camera from different angles of the symmetric portion, and a feature point is drawn from each image. Then, each feature point is connected to the projection center of the image, a straight line in the three-dimensional space is calculated, and a three-dimensional voxel assumed in the three-dimensional space where the object representing the feature point exists is drawn.

[0007]

The above-mentioned conventional range finder has the following problems.

First Problem In the range finder of the prior art, since the projection point of the structured light and the position of the CCD for detecting the reflected light are fixed, the shadow portion where the structured light is not illuminated when measuring an object. Occurs, and if the characteristic point or the characteristic line to be extracted is in the shadow portion, the target characteristic point or the characteristic line cannot be extracted.

Second Problem When the structured light has a plurality of shooting points, a plurality of optical systems for forming the structured light are provided, or one light source is used and the light emitted from the light source is divided. As a result, the optical system becomes large, the range finder becomes large, and the weight becomes large.

Third Problem In the prior art, the positions of the projection point and CCD are fixed, and the direction of structured light (longitudinal direction) and the image direction of CCD (either X or Y direction) are matched. However, because of the fixing method, the adjustment is difficult and the assembly time is long.

Fourth Problem When the CCD mounting position is fixed and a plurality of structured lights are used, for example, when there are two structured lights, 90 °, 180 ° and 270 ° are arranged in the same plane as an arrangement for eliminating shaded portions. However, the assembly time is required for the number of emitted lights, and
As with the above problem, it takes assembling time.

Fifth Problem The pixel array of the CCD is fixed (for example, the pixel array is X: 5).
12, Y: 256), and therefore the resolution for each direction is also fixed. Therefore, if the mounting position of the CCD is fixed, the detection resolution with respect to a plurality of structured lights becomes high and low, and uniform measurement resolution cannot be obtained, resulting in deterioration of accuracy.

Sixth Problem In the case of the conventional technique, the area of the shadow portion changes depending on the position of the object within the measurement visual field. (In the field of view, the closer to the projection point,
The shadow is small). Therefore, in order to acquire the data of the area of the shadow portion, it is necessary to move the entire apparatus or move the object itself, which requires a moving mechanism and increases the apparatus cost.

Seventh Problem In the case of the conventional technique, in order to obtain the distance image of the shadow portion, it is necessary to move the entire apparatus to capture a plurality of pieces of image data and to obtain the distance data of the shadow portion. However, the processing time becomes long and the measurement takes time.

The present invention has been made in view of the above-mentioned circumstances, and it is possible to obtain distance data having no shadow portion with high accuracy and high reliability.
Moreover, it is an object of the present invention to provide an inexpensive and small range finder that can be measured in a short time and that facilitates various adjustments such as the irradiation direction of structured light with respect to the pixel direction of the CCD.

[0016]

According to a first aspect of the present invention, there is provided a measuring device for measuring a three-dimensional shape of an unknown object, which comprises an optical system for forming structured light and the structured light for the unknowable object. In a range finder having a projection mechanism for scanning and projecting, and an imaging system for detecting reflected light from the object, the projection point of the structured light is on a plane perpendicular to the central axis of the imaging system from the central axis. The present invention is characterized in that it can be set within an arbitrary predetermined angle range separated by a certain distance, so that distance data without shadow can be obtained, and measurement reliability is improved and accuracy is improved.

According to a second aspect of the present invention, in the projection point moving type range finder according to the first aspect, the optical system and the projection mechanism are integrally attached to a rotary table, and the rotary table is mounted on the central axis of the image pickup system. It is characterized in that it is rotatably supported around it, so that it is possible to eliminate the optical system necessary for projecting a plurality of points and to downsize the apparatus.

According to a third aspect of the present invention, in the projection point moving type range finder according to the first or second aspect, an optical encoder having a slit is attached to the rotary table, and the reflected light detecting element of the image pickup system and the detecting element. It is characterized in that the rotation angle position of the projection point can be detected, so that the direction of the structured light can be easily aligned with the pixel direction of the CCD and the assembling time can be shortened.

According to a fourth aspect of the present invention, in the projection point moving type range finder according to the first or second aspect, a fixed case for rotatably supporting the rotary table is provided with a rotary motor for rotationally driving the rotary table. It is characterized by having a control means capable of arbitrarily controlling the angular position of the projection point with respect to the detection element of the reflected light, so that the angular relationship between the projection point and the CCD at a plurality of positions can be easily adjusted. Is shortened.

According to a fifth aspect of the present invention, in the projection point moving type range finder according to the first or second aspect, the entire imaging system is supported by the fixed case so as to be rotatable about a central axis of the imaging system. As a feature, the fixed position of the CCD can be freely selected, and the device resolution is increased in the direction in which accuracy is required to improve the accuracy.

According to a sixth aspect of the present invention, in the projection point moving type range finder according to the first or second aspect, the structured light is projected on the unknowable object by sequentially changing the angular position from the plurality of projection points. Characterized by having control means for detecting and controlling the angular position that minimizes the shadow area,
The device can be provided inexpensively without the need for an external object moving mechanism.

According to a seventh aspect of the invention, in the projection point moving type range finder according to the first or second aspect, the range image data obtained by sequentially projecting the structured light from a plurality of the projection points is synthesized. The present invention is characterized in that a processing unit for generating a distance image of a shadow portion is provided so that the time required for measurement can be shortened.

[0023]

1 is a view for explaining an example of a robot handling system having a projection point moving type range finder according to the present invention, in which 1 is a projection point moving type range finder, Hereinafter, it will be referred to as a range finder.) 2 is a hand, 3 is a robot, 4 is a work,
Reference numeral 5 is a stand, 6 is an image processing apparatus, 7 is a robot controller, and 8 is a host computer.

In the robot handling system shown in FIG. 1, a range finder 1 is mounted on the tip of the robot 3, and the range finder 1 is attached to the tip of the robot 3 based on image information obtained from the range finder 1. Hand 2
Thus, the work 4 placed on the stand 5 in an irregular posture is handled. The image processing information obtained from the range finder 1 is sent to the host computer 8 via the image processing device 6, the posture of the work 4 is calculated, and the grip position of the work 4 is calculated. These calculation results are sent to the robot controller 7, and the robot controller 7 drives the robot 3 and the hand 2 to hold the work 4.

FIG. 2 is a view for explaining an example of the embodiment of the projection movement type range finder according to the present invention.
2A is a plan view and FIG. 2B is a view BB of FIG. 2A.
2C is a perspective view of the optical encoder 24, FIG. 2D is a perspective view showing the shadow of the work 4, and FIG. 2E is a plan view showing the relationship between the CCD 10 and structured light. In the figure, 9 is an image pickup system lens, 10 is an image pickup system CCD, and 11
Is an image pickup holder for housing the lens 9 and the CCD 10,
14 is a bearing, 13 is a fixed case, 15 is a turntable, 16 is a driven gear attached to the turntable 15, and 17 is the turntable 1.
5 is a drive gear, 18 and 22 are laser diodes (hereinafter,
LD)), 19 is an optical system cylindrical lens,
Reference numeral 20 is a carbano mirror of the optical scanning mechanism, and 21 is a light receiving element 2.
3, support arm 23, light receiving element 23, optical encoder 24,
Reference numeral 5 is a rotary motor for driving the rotary base 15, 26 is a drive motor for the carbano mirror 20, 27 is a fixing screw for the imaging holder 11, 28 is structured light (slit light), 29 is a central axis of the imaging system, and 30 is an optical system. , 31 is an optical scanning mechanism (hereinafter referred to as a scanning mechanism), and 32 is a projection point.

In the range finder 1 shown in FIG. 2, the optical axis of the image pickup system including the lens 9 and the CCD 10 is the central axis 2.
9, an imaging holder 11 accommodating the imaging system, a fixed case 13 that coaxially supports the imaging holder 11, a rotary table 15 that is supported by the fixed case 13 and rotates coaxially with a central axis 29, and a rotary table. The optical system 30 and the optical scanning mechanism 31 are attached to the optical system 15.

The image pickup holder 11 accommodating the image pickup system is coaxially fixed to the fixed case 13 whose rotational position is adjusted via a bearing 12 in a cylindrical fixed case 13. That is, the image pickup holder 11 is provided with a fixing screw 27, and the fixing screw 27 can be rotated and fixed to the fixing case 13. A coaxial bearing 14 is provided outside the cylindrical fixed case 13, and a rotary base 15 is rotatably supported by the fixed case 13 via the bearing 14.

On the rotary table 15, the optical system 3 is arranged so that its optical axis is parallel to the plane perpendicular to the central axis 29 of the image pickup system.
0 and the scanning mechanism 31 are fixed. The optical system 30 comprises an LD 18 and a cylindrical lens 19, a scanning mechanism 31 has a carbano mirror 20 which is driven to rotate by a drive motor 26, and a projection point 32 of the galvanometer mirror 20.
A constant distance m is maintained between the image pickup system central axis 29 and the image pickup system central axis 29. Further, the driven gear 16 and the optical encoder 24, which are coaxial with the central shaft 29, are fixed to the rotary base 15, and the fixed case 13
A rotary motor 25 having a drive gear 17 fixed to a shaft is attached to the drive gear 17, and the drive gear 17 and the driven gear 16 fixed to the rotary base 15 are arranged at a meshing position.

The optical encoder 24 has an annular shape as shown in FIG. 2C and has a slit 2 having a constant width in the radial direction from the center.
The LDs 4a are provided at equal intervals and are mounted on the fixed case 13, and the support arm 2 is provided at a position facing the LD22.
It is set between the light receiving element 23 and the light receiving element 23 fixed to 1.
On the other hand, the laser light emitted from the LD 18 of the optical system 30 is beam-shaped by the cylindrical lens 19 into structured light (slit light) 38, reflected at the projection point 32 of the carbano mirror 20, and projected downward in the plane of FIG. To be done.

With the above construction, the rotary motor 25
When the rotary table 15 is rotated coaxially with respect to the fixed case 13 by applying a control signal, the projection point 32 can be set at an arbitrary angular position with respect to the CCD 10 while maintaining a fixed distance m. Further, by loosening the fixing screw 27 provided on the image pickup holder 11 and rotating the image pickup holder 11 with respect to the fixed case 13, the rotational position of the CCD 10 can be freely changed. With the above configuration, the position of the work 4 is shown in FIG.
Even if a shadow portion is generated when the structured light is projected at the position shown in, the stepped portion 4a of the work 4 which is hidden in the shadow can be measured, for example, when the rotary table 15 is rotated by 180 °. Further, by rotating the image pickup holder 11 and changing the angle of the projection point 32 with respect to the CCD 10, it is possible to change the angle shown in FIG.
As shown in (E), it is possible to easily adjust the structured light 28 for the CCD 10 so as to coincide with the direction of the arrow Y. Next, the projection point angular position control means will be described.

FIG. 3 is a block diagram for explaining an embodiment of the projection point angle control means relating to the projection point moving type range finder of the present invention, in which 33 is the projection point angular position control means and 34 is the projection point angle position control means. A pulse counter, 35 is a motor driver.

Projection point angular position control means 33 shown in FIG.
Is composed of a pulse counter 34 and a motor driver 35, and the rotary motor 25 is connected to and driven by the motor driver 35. For example, when a pulse motor is used as the rotary motor 25, the target pulse number 34b is set in advance in the pulse counter 34 of the projection point angular position control means 33, and the encoder signal 3 from the optical encoder 24 is set.
Enter 4a. The target pulse number 34b is set to, for example, the number of pulses at which the projection point angular position is 90 °, 180 °, 270 °, and is set by comparing this with the signal pulse number of the encoder signal 34a from the encoder 24. A stop signal can be sent to the rotary motor 25 when the rotation angle corresponding to the generated number of pulses is reached. Here, since the entire image pickup system is rotatable with respect to the central axis 29, even if the number of pixels of the CCD 10 in the X and Y directions is different, it is possible to manually select the resolution. Here, when it is desired to always optimize the directional resolution, the imaging holder 11 may be rotatable with respect to the fixed case 13 by a motor or the like.

Next, the shadow area minimizing means and the shadow part distance data generation processing section will be described with reference to FIGS. 4 and 5.

FIG. 4 is a block diagram for explaining an embodiment of the shadow area minimization means of the projection point moving type range finder according to the present invention. In the figure, 36 is the shadow area minimization means, 3
7 is a D / A converter, 38 is a motor driver, 39 is a switch circuit, 40 is a laser diode (LD) driver, 41 is a static memory, and 42 is a microcomputer.

In FIG. 4, the shadow area minimizing means 36 is
An optical scanning mechanism driving means for driving the galvano mirror 20 of the optical scanning mechanism 31, an optical system driving means for driving the LD 18 of the optical system 30, and a projection angle control means 33 shown in FIG.
CCD 10 and static memory 41 for storing its brightness signal
And a microcomputer 42. In the above structure, the optical scanning mechanism driving means of the galvanometer mirror 20 is composed of the drive motor 26, the motor driver 38, and the D / A converter 37 that produces a control signal for the motor driver 38. The LD18 optical system driving means turns on the power source of the LD18.
It is composed of a switch circuit 39 for turning on / off and an LD driver 40. Next, the operation of the shadow area minimizing means 36 shown in FIG. 4 will be described with reference to FIG.

FIG. 5 is a diagram for explaining the operation of the shadow area minimizing means shown in FIG. As shown in FIG. 5A, the LD 1 is attached to the work (detection object) 4 on the stand 5.
When the laser beam emitted from 8 is irradiated through the galvano mirror 20, a shadow 5a is produced. For example, the shape of the work 4 is a simple square plate, the sides of the square are X and Y directions, and the height is Z direction. The brightness of the work 4 in the X axis direction is detected by the CCD 10. The luminance in the case of non-irradiation without emitting the laser light from the LD 18 is the luminance of the level shown by the dotted line LB ₀ in FIG. 5B, but when the laser light is emitted, it is shown in FIG. 5C.
A shadow 5a portion having a low level of luminance like LC ₁ is produced. The microcomputer 42 compares LB ₁ (solid line) obtained by adding a certain slight offset to the non-illuminated brightness LB ₀ with the brightness LC ₁ shown in FIG. 5C. This result shows that the non-irradiated luminance LB ₁ is larger than the total illuminated luminance LC ₁ in the section X _{1 to} X ₂ as shown in FIG. This operation is performed by driving the projection angle control means 33 to set a predetermined angle, for example, 0 °, 90 °, 180 °, 2
The projection point 32 is sequentially moved by rotating 70 °, and the angular position of the projection point 32 at which the shadow area is minimized is detected.

FIG. 6 is a diagram for explaining an embodiment of a shadow portion distance data generation processing unit of the projection point moving type range finder according to the present invention. FIG. 6A shows a shadow portion distance data generation processing unit. FIG. 6B is a perspective view showing a state in which the irradiation angle of structured light with respect to the work is changed.
In the figure, 43 is a distance data generation processing unit of a shadow portion, and 44 is 2
A digitization circuit, 45 is a space code memory, and 46 is a memory.

The distance data generation processing unit 43 of the shadow portion shown in FIG. 6 obtains the height on the Z axis of the work of the portion which produces the shadow based on the principle of the space coding method. The data generation processing unit 43 includes a binarization circuit 44, a space code memory 45, a static memory 41, a microcomputer 42 and a memory 46. The binarization circuit 44 and the space code memory 45 are connected in series, and are connected by switching the contacts on one side of the two-way selector switches SW ₁ and SW ₂ between the CCD 10 and the stationary memory 41. Is binarized by the binarization circuit 44, and this is binarized in the space code memory 4
It is converted into a binary code at 5 and input to the static memory 41. The contacts on the other side of the switches SW ₁ and SW ₂ are directly connected to each other, and a raw image which is not binary coded is input to the static memory 41 to eliminate the occurrence of a binarization error caused by a change in luminance of the raw image.

In the space coding method, structured light by laser light is projected over a measurement range from a projection point 32 located at a position m away from the central axis 29 of the image pickup system in the direction perpendicular to the axis,
This is a stereoscopic measurement system that obtains a distance image by the triangulation method from the image signal of the reflected light detected by the CCD 10. Specifically, first, the area of half the measurement range is not illuminated by turning off the structured light power, the next half area is optically scanned by turning on the power, and then, for each 1/4 of the measurement range. Turn structured power on and off to scan, then power on and off sequentially
The area interval is halved and the power of the image input signal is set to "0" and the ON state is set to "1", and is coded in a binary number. An image having a binary code having a digit of the number of times of scanning by the binary code for each scan is defined on the measurement surface. When the measurement surface is flat, the codes are arranged in order, but when there is a high portion in the solid, a shadow is generated and the binary code array is changed. Since this array depends on the height, the height can be obtained by a method similar to triangulation.

In the present invention, as shown in FIG. 6 (B), the work 4 is first subjected to structured light indicated by the solid line from the projection point 32 of the galvano mirror 20 to obtain the work from the illuminance data. The shadow detection position 4 and the end position are stored. Next, for example, the projection point 32 (not shown) at a position different by 180 ° from the position of the first projection point 32 shown by the solid line
In the distance data obtained by projecting the structured light shown by the dotted line, since the shadow start position approximately corresponds to the end position, the position data at this time is taken in and added to the first distance data. Here, it is desirable to set the shadow portion to 0 (zero) in the first distance data. Furthermore, since the illuminance data is obtained at the angular position that minimizes the shadow portion, it is not necessary to capture all of the second range image in the space coding method.
The measurement time can be shortened.

[0041]

【The invention's effect】

Effect corresponding to claim 1: A measuring device for measuring a three-dimensional shape of an unknown object, an optical system for forming structured light, and a projection mechanism for scanning and projecting the structured light onto the unknowable object.
In a range finder having an imaging system that detects reflected light from the object, the projection point of the structured light is at an arbitrary predetermined angle with a certain distance from the central axis of the imaging system on a plane perpendicular to the central axis. Since the range can be set, distance data without shadow can be obtained, and the reliability and accuracy of measurement can be improved.

Effect corresponding to claim 2: In the projection point moving type range finder according to claim 1, the optical system and the projection mechanism are integrally attached to a rotary base, and the rotary base is the center of the imaging system. The device can be miniaturized because it is rotatable about its axis and does not have an optical system necessary for projecting multiple points.

Effect corresponding to claim 3: In the projection point moving type range finder according to claim 1, an optical encoder having a slit is attached to the rotary table, and the detection element of the reflected light of the imaging system and the projection. Since the rotation angle position of the point can be detected, the direction of the structured light and the pixel array direction of the CCD can be easily matched, and the assembly time can be shortened.

Effect corresponding to claim 4: Claim 1 or 2
In the projection point moving type range finder described in (1), a fixed case that rotatably supports the rotary table is provided with a rotary motor that rotationally drives the rotary table, and the angular position of the projection point with respect to the detection element of the reflected light is arbitrary. Since the control means capable of controlling the above is provided, the angular relationship between the projection point and the CCD at a plurality of positions can be easily adjusted, and the assembly time can be shortened as in the above (3).

Effect corresponding to claim 5: claim 1 or 2
In the projection point movement type lens finder described in (3), since the entire image pickup system is rotatably supported by the fixed case around the central axis of the image pickup system, the fixed position of the CCD can be freely selected and the direction where accuracy is required is set. Therefore, the device resolution can be increased and the accuracy can be improved.

Effect corresponding to claim 6: Claim 1 or 2
In the projection point moving type range finder according to claim 7, a control means for detecting and controlling an angular position that minimizes a shadow area due to the structured light projected on the unknowable object by sequentially changing angular positions from a plurality of the projection points. Since the device is provided, the cost of the device can be reduced without the need for an external object moving mechanism.

Effect corresponding to claim 7: claim 1 or 2
In the projection point movement type range finder described in (1), since the processing unit that generates the distance image of the shadow portion by synthesizing the distance image data obtained by sequentially projecting the structured light from the plurality of the projection points is provided. The time required for measurement can be shortened.

[Brief description of drawings]

FIG. 1 is a robot handling system having a projection point moving type range finder according to the present invention.

FIG. 2 is a diagram for explaining an example of an embodiment of a projection movement type range finder according to the present invention.

FIG. 3 is a block diagram for explaining an embodiment of projection point angle control means according to the projection point moving type range finder of the present invention.

FIG. 4 is a block diagram for explaining an embodiment of shadow area minimizing means of the projection point moving type range finder according to the present invention.

FIG. 5 is a diagram for explaining the operation of the shadow area minimizing means of the block diagram shown in FIG.

FIG. 6 is a diagram for explaining an embodiment of a distance data generation processing unit of a shadow portion of a projection point moving type range finder according to the present invention.

[Explanation of symbols]

1 ... Range finder, 2 ... Hand, 3 ... Robot, 4
Work, 5 ... Stand, 6 ... Image processing device, 7 ... Robot controller, 8 ... Host computer, 9 ... Lens, 10 ... CCD, 11 ... Imaging holder, 12, 14 ... Bearing, 13 ... Fixed case, 15 ... Rotating table, 16 ... Driven gear, 17 ... Drive gear, 18 ... Laser diode (L
D), 19 ... Cylindrical lens, 20 ... Carbano mirror, 21 ... Support arm, 22 ... Laser diode, 23 ...
Light receiving element, 24 ... Optical encoder, 25 ... Rotation motor, 2
6 ... Drive motor, 27 ... Fixing screw, 28 ... Structured light, 2
9 ... Central axis of imaging system, 30 ... Optical system, 31 ... Scanning mechanism (scanning mechanism), 32 ... Projection point, 33 ... Projection point angular position control means, 34 ... Pulse counter, 35, 38 ... Motor driver, 36 ... Shadow portion minimizing means 37 ... D / A converter, 39 ... Switch circuit, 40 ... LD driver, 41
... static memory, 42 ... microcomputer, 43 ... distance data generation processing unit, 44 ... binarization circuit, 45 ... spatial code memory,
46 ... memory.

Claims (7)

[Claims] 1. A measuring device for measuring a three-dimensional shape of an unknown object, comprising: an optical system for forming structured light; a projection mechanism for scanning and projecting the structured light onto the unknowable object; In a range finder having an image pickup system for detecting reflected light, the projection point of the structured light can be set to an arbitrary predetermined angle range separated from the central axis of the image pickup system by a predetermined distance on the plane perpendicular to the central axis. This is a range finder with movable projection point. 2. The projection according to claim 1, wherein the optical system and the projection mechanism are integrally attached to a turntable, and the turntable is rotatably supported around a central axis of the image pickup system. Point move type range finder. 3. An optical encoder having a slit is attached to the rotary table so that a rotational angle position of the detection element of the reflected light of the imaging system and the projection point can be detected. The projection point moving type range finder described in. 4. A fixed case that rotatably supports the rotary table is provided with a rotary motor that rotationally drives the rotary table, and the angular position of the projection point with respect to the detection element of the reflected light can be arbitrarily controlled. The projection point moving type range finder according to claim 1 or 2, further comprising control means. 5. The projection point moving type range finder according to claim 1, wherein the entire imaging system is supported by the fixed case so as to be rotatable about a central axis of the imaging system. 6. A control means for detecting and controlling an angular position that minimizes a shadow area of the structured light projected on the unknowable object by sequentially changing angular positions from a plurality of the projection points. The projection point moving type range finder according to claim 1 or 2. 7. A processing unit for generating a distance image of a shadow portion by synthesizing distance image data obtained by sequentially projecting the structured light from a plurality of the projection points. The projection point moving type range finder described in 1 or 2.