JP6774929B2 - Three-dimensional measuring device - Google Patents

Description

The present invention relates to a three-dimensional measuring device that measures the shape of a measurement object by irradiating the measurement object with light and imaging the measurement object.

Conventionally, there is known a shape measuring device that measures the surface shape of a work by scanning the surface of an object to be measured (hereinafter referred to as "work") with a probe and capturing the position coordinates of each part of the work. As such a shape measuring device, a so-called stylus that is provided in contact with the surface of the work is provided to measure the position coordinates of the work, or a stylus is not brought into contact with the surface of the work by means of an optical system. A non-contact type that makes measurements is known.

Such a non-contact type surface shape measuring device is an irradiation optical system that irradiates a work with irradiation light along a predetermined plane from a predetermined irradiation direction, and an image pickup that captures the shape of the projected light projected on the surface of the work. It is equipped with a non-contact probe consisting of a device. The irradiation optical system includes a light source that irradiates a linear laser beam (point laser) toward the work, and an irradiation light adjusting means that adjusts the laser beam emitted by the light source into a flat surface (sheet shape). By this irradiation optical system, irradiation light (also called a line laser, a laser sheet, a laser light sheet, etc.) along a predetermined plane is irradiated toward the work surface at a position where the irradiation light and the work surface intersect. Is projected light according to its shape, that is, light having a contour shape of the work. The imaging device images a work (projected light projected on the surface) from a predetermined imaging direction different from the irradiation direction of the light source.

With the above configuration, projection is performed on the work surface using the triangulation method based on the irradiation direction of the irradiation optical system, the imaging direction of the imaging device, the distance between the irradiation optical system and the imaging device, and the captured image. It is possible to calculate the spatial coordinates of the projected light, that is, the contour shape of the work.

In such a non-contact type surface shape measuring device, as described above, the irradiation direction and the imaging direction of the irradiation optical system are different. Therefore, for example, if the distance between the probe and the work is too close or too far, the projected light projected on the surface of the work does not enter the imaging range of the imaging device, and imaging cannot be performed. .. It is possible to check from the display whether the distance between the probe and the workpiece is appropriate, but in that case, the operator must visually recognize both the display and the sample table, which leads to a decrease in operability. Was there.

Conventionally, in order to solve such a problem, in addition to the above probe, an instruction light emitting unit that irradiates an instruction light having a wavelength different from that of the laser is provided, and when the laser is out of the measurable range, By turning on the indicator light emitting unit and irradiating the workpiece with the indicator light, it is possible to confirm whether or not the laser beam is located within the measurable range of the workpiece (Patent Document 1).

Japanese Unexamined Patent Publication No. 2012-127805

However, in the method described in Patent Document 1, in order to confirm whether or not the laser beam is located within the imaging range of the work, it is necessary to separately provide an indicator light emitting unit having a wavelength different from that of the laser beam. There is a problem that the manufacturing cost of the laser increases. In addition, since the indicator light emitting part is turned on separately from the laser light, power consumption increases, which may cause heat drift or malfunction due to heat generation of the illumination light emitting part. Even if a cooling fan is attached, the cooling fan The vibration caused by the light is transmitted to the probe, which may reduce the measurement accuracy. Further, in such a case, it is necessary to provide an air hole for cooling in the measuring probe, which leads to a decrease in environmental resistance.

The present invention has been made in view of these points, and an object of the present invention is to provide a three-dimensional measuring device having excellent operability and environmental resistance at low cost.

The three-dimensional measuring device according to the present invention has an irradiation optical system that irradiates a work with irradiation light along a predetermined plane, and a plurality of image pickup elements arranged on an image pickup surface, and has a position different from the predetermined plane. It is provided with a non-contact probe having an image pickup device that images a work from the image sensor and a control unit that controls an irradiation optical system according to an output signal of the image pickup device. In addition, this control unit determines whether or not the image pickup element arranged in the predetermined image pickup region on the image pickup surface detects the projected light projected on the surface of the work by the irradiation light from the irradiation optical system, and performs imaging. When the image sensor arranged in the region detects the projected light, the light emitted from the irradiation optical system is turned on, and when the image sensor arranged in the imaging region does not detect the projected light. Blinks the irradiation light emitted from the irradiation optical system at a predetermined cycle.

In addition, the control unit has a threshold value for the amount of light received among the image pickup elements arranged in the image pickup region (referred to as the minimum amount of light received by the image pickup element, which is the same in the present specification). If there is an image sensor that exceeds the threshold value, it is determined that the image sensor arranged in the image pickup area is detecting the projected light, and among the image sensor elements arranged in the image pickup area, the received light amount exceeds the threshold value. When the image sensor is not present, it may be determined that the image sensor arranged in the image pickup region does not detect the projected light.

That is, in the three-dimensional measuring device according to the present invention, when the image pickup device arranged in the image pickup region detects the projected light, the irradiation light emitted from the irradiation optical system is turned on and arranged in the image pickup region. When the image sensor does not detect the projected light, the irradiation light emitted from the irradiation optical system blinks at a predetermined cycle. Therefore, when the distance between the probe and the work is out of the predetermined distance range and the projected light is no longer imaged by the image pickup element arranged in the image pickup region of the light receiving surface of the image pickup device, the irradiation light emitted from the irradiation optical system. Flashes. Therefore, the operator can confirm whether or not the distance between the probe and the work is appropriate only by visually observing the probe and the work, and it is possible to provide a three-dimensional measuring device having excellent operability. is there. Further, when the amount of light received by the image sensor arranged in the image pickup region of the light receiving surface of the image pickup device is below the threshold value, the shape of the work cannot be measured, so that the light emitted from the irradiation optical system is emitted. Blinking does not affect the measurement.

Further, according to the present invention, since it is not necessary to provide the probe with an indicator light emitting unit, it is possible to suppress various problems caused by the above heat generation, and the probe can be downsized and reduced in cost by reducing the number of parts. It is possible to make it.

The three-dimensional measuring device according to the embodiment of the present invention detects the distance between the probe and the work by the position of the image sensor that detects the projected light in a predetermined observation area wider than the predetermined image pickup area on the image pickup surface. When the image sensor arranged in the image pickup region does not detect the projected light, the irradiation light emitted from the irradiation optical system blinks at a cycle corresponding to the detected distance. In the three-dimensional measuring device according to such an embodiment, since the distance between the probe and the work is detected by the image sensor in the observation region, the distance between the probe and the work can be adjusted more preferably.

The three-dimensional measuring device according to another embodiment of the present invention can be selectively operated by the first operation mode and the second operation mode, and the control unit is a control unit of each image pickup device arranged in the image pickup region. The amount of light received is detected, and in the first operation mode, if there is an image sensor whose amount of light received exceeds the threshold value among the image sensors arranged in the image pickup region, the irradiation is irradiated from the irradiation optical system. The light is turned on, and when there is no image sensor whose light receiving amount exceeds the threshold value among the image sensors arranged in the image pickup region, the irradiation light emitted from the irradiation optical system is blinked at a predetermined cycle. In addition, in the second operation mode, when the light receiving amount of each image pickup element in the image pickup region is saturated, the control unit is subjected to the irradiation optical system at the time of the next light reception. The amount of irradiation light to be irradiated is reduced, and when there is no image sensor whose light reception amount is saturated, the light amount of irradiation light emitted from the irradiation optical system at the time of the next light reception is increased. Further, when the light amount of the irradiation light emitted from the irradiation optical system reaches the maximum light amount at the time of receiving light from the image pickup element and the light receiving amount is below the threshold value, the light is emitted from the irradiation optical system at the time of the next light receiving. The amount of irradiation light is set to the minimum amount.

In the three-dimensional measuring device according to such an embodiment, the first operation mode is a manual operation measurement mode in which the probe is manually operated to perform measurement, and the second operation mode is the automatic probe. It is also possible to set the automatic operation measurement mode in which measurement is performed by operating. For example, when the three-dimensional measuring device is driven by CNC operation, it is conceivable to first teach the three-dimensional measuring device and then automatically operate the three-dimensional measuring device. Here, when teaching, the operator needs to visually recognize the probe and the work, and the teaching can be easily performed by applying the first operation mode. On the other hand, when the three-dimensional measuring device is driven by CNC operation, the probe is automatically driven according to the result of teaching, so that the operator does not need to visually check the distance between the probe and the work one by one. Further, in this case, by applying the second operation mode and automatically adjusting the amount of irradiation light emitted from the irradiation optical system, it is possible to perform suitable measurement. It is also possible to switch between the first operation mode and the second operation mode when the operator operates the probe, for example, such as teaching.

It should be noted that the present invention can be realized at low cost by software, firmware, or the like, and can also be applied to an existing three-dimensional measuring device. Further, for example, when the present invention is realized by software or the like and the instruction light emitting unit mounted on the existing device is turned off by the software or the like, the problem due to the above heat also occurs when the existing device is used. It is possible to improve the operability while avoiding the above.

According to the present invention, it is possible to provide a three-dimensional measuring device having excellent operability and environmental resistance at low cost.

It is an overall view of the system which comprises the 3D measuring apparatus which concerns on 1st Embodiment of this invention. It is a figure which shows the structure of the optical probe 17 in this apparatus. It is the schematic which shows the optical probe 17 of the apparatus and the irradiation light which irradiated using it. It is the schematic which shows the arrangement in the optical probe 17 of the irradiation optical system 172 and the image pickup apparatus 173 of the apparatus. It is a schematic diagram which shows the CMOS image sensor 1732 of the apparatus. It is a schematic diagram for demonstrating the image pickup area 321 and the observation area 322 of the CMOS image sensor 1732. It is a block diagram which shows the control system of the optical probe 17 of this apparatus. It is a flowchart for demonstrating the operation of the 3D measuring apparatus of this apparatus. It is a flowchart for demonstrating the operation of the 3D measuring apparatus which concerns on 2nd Embodiment of this invention. It is a schematic diagram for demonstrating the operation of this apparatus. It is a flowchart for demonstrating operation of this apparatus. It is a flowchart for demonstrating operation of the 3D measuring apparatus which concerns on 3rd Embodiment of this invention. It is the schematic which shows the arrangement in the optical probe 17 of the irradiation optical system 172'and the image pickup apparatus 173' of the 3D measuring apparatus which concerns on 4th Embodiment of this invention.

[First Embodiment]
Next, the three-dimensional measuring apparatus according to the first embodiment of the present invention will be described in detail with reference to the drawings. FIG. 1 is an overall view of a system constituting the three-dimensional measuring device according to the present embodiment. This three-dimensional measuring device is configured by mounting the non-contact optical probe 17 according to the present embodiment as a measuring probe of the three-dimensional measuring device 1. The three-dimensional measuring device includes a drive control device 2 for driving and controlling the three-dimensional measuring device 1 and taking in necessary measurement coordinate values from the three-dimensional measuring device 1, and the tertiary via the drive control device 2. The operation panel 3 for manually operating the original measuring device 1 and the part program instructing the measurement procedure in the drive control device 2 are edited and executed, and the measured coordinate values captured via the drive control device 2 are geometrically obtained. It is composed of a host system 4 having a function of performing calculations for fitting shapes and recording and transmitting part programs.

The three-dimensional measuring device 1 is configured as follows. That is, the surface plate 11 is placed on the vibration isolation table 10 so as to coincide with the horizontal plane with the upper surface as the base surface, and the arm supports 12a and 12b erected from both side ends of the surface plate 11 The X-axis guide 13 is supported at the upper end. The lower end of the arm support 12a is driven in the Y-axis direction by the Y-axis drive mechanism 14, and the lower end of the arm support 12b is movably supported on the surface plate 11 in the Y-axis direction by an air bearing. .. The X-axis guide 13 drives the Z-axis guide 15 extending in the vertical direction in the X-axis direction. The Z-axis guide 15 is provided so that the Z-axis arm 16 is driven along the Z-axis guide 15, and a non-contact optical probe 17 is attached to the lower end of the Z-axis arm 16. The optical probe 17 may be rotatable in a horizontal plane or may be rotatable in a plane perpendicular to the horizontal plane.

FIG. 2 is a schematic view showing the configuration of the optical probe 17 of the three-dimensional measuring device according to the present embodiment, and FIG. 3 is a perspective view as well. The optical probe 17 determines the amount of light emitted from the housing 171 and the irradiation optical system 172 arranged in the housing 171, the image pickup device 173 for imaging the work, and the irradiation optical system 172 according to the output of the image pickup device 173. It is configured to include a control circuit 174 for adjustment.

The irradiation optical system 172 irradiates the work 5 with irradiation light along a predetermined plane (irradiation surface) S3. The irradiation optical system 172 includes a laser light source 1721 and a beam expander 1723. The laser emitted from the laser light source 1721 is widened by the beam expander 1723 in the direction orthogonal to the paper surface to become the irradiation light along the predetermined plane S3. The beam expander 1723 is, for example, a rod lens or a cylindrical lens. In addition, when the term "irradiation light" is used in the present specification, it means the light after being irradiated from the irradiation optical system 172 and before reaching the surface of the work 5. In the present embodiment, a point light source is combined with a cylindrical lens or the like to generate irradiation light along a predetermined plane, but the LEDs are arranged linearly and combined with an optical system such as a frost to form a linear shape. Other methods may be used, such as those that produce the light of.

The projected light projected on the surface of the work 5 spreads linearly or curvedly along a straight line or a curve formed by a set of intersections of a predetermined plane S3 and the surface of the work 5. In other words, the projected light is projected onto the contour of the cut surface when the work 5 is cut by the predetermined plane S3. When the term "projected light" is used in the present specification, it means the linear light that can be imaged when the irradiation light reaches the surface of the work 5 and is reflected by the surface.

The image pickup apparatus 173 includes an optical system 1731 provided with a bandpass filter 1731a and a lens 1731b for passing the wavelength of the projected light, and a CMOS sensor 1732 that captures an image of the work 5 via the optical system 1731. The work 5 is imaged from a position different from that of S3. That is, the projected light projected on the surface of the work 5 and reflected along the shape of the surface of the work 5 is received by the image pickup apparatus 173 from a predetermined angle. The bandpass filter 1731a is effective in that it shields noise light other than the projected light and transmits only the projected light to improve the measurement accuracy, but it is not essential and can be omitted. Is.

FIG. 3 shows the irradiation light and the projected light irradiated by the optical probe 17. As shown in FIG. 3A, when the projected light L is projected onto the work 5 by the irradiation optical system 172, the projected light is deformed along the uneven shape of the surface of the work 5, and the work 5 is cut by the irradiation surface S3. The outline is illuminated. As shown in FIG. 3B, the image pickup apparatus 173 images the work 5 from a position different from the predetermined irradiation surface S3, and acquires an image of the projected light L seen from the position as L'.

FIG. 4 is a schematic view showing the arrangement of the irradiation optical system 172 and the imaging device 173 in the optical probe 17. In FIG. 4, the bandpass filter 1731a is omitted.

The principle of Scheimpflug is used for the optical probe 17 according to the present embodiment, and as shown in FIG. 4, the surface including the imaging surface of the CMOS sensor 1732 (hereinafter, referred to as “imaging surface S1”). The main plane S2 including the main point of the lens 1731b and the irradiation surface S3 of the irradiation light irradiated to the work 5 are located at the point P and intersect with each other by one line orthogonal to the paper surface. In the present embodiment, with such an arrangement, the entire image plane S1 of the CMOS sensor 1732 is in focus with respect to the irradiation surface S3. Here, the distance between the irradiation optical system 172 and the image pickup apparatus 173 is known, and the angle between the image pickup surface S1 and the irradiation surface S3 is also known. Further, the distance between the position of the surface of the work 5 on which the projected light is projected and the irradiation optical system 172 is specified from the position of the image sensor that receives the projected light reflected on the surface of the work 5. Therefore, from the distance between the irradiation optical system 172 and the image pickup device 173, the angle between the image pickup surface S1 and the irradiation surface S3, the position of the surface of the work 5 irradiated with the irradiation light, and the distance between the irradiation optical system 172, the optical method is used. The positional relationship between the probe 17 and the portion of the work 5 on which the projected light is projected can be calculated. Further, the positional relationship between the optical probe 17 and the surface plate 11 is specified by an encoder or the like mounted inside the X-axis guide 13, the Y-axis drive mechanism 14, the Z-axis guide 15, and the like. Therefore, it is possible to calculate the position of the portion of the work 5 on which the projected light is projected on the surface plate 11.

FIG. 5 is a schematic view showing the CMOS image sensor 1732 according to the present embodiment. The CMOS image sensor 1732 includes a plurality of image pickup elements arranged in a matrix on the light receiving surface, and in the present embodiment, the direction in which the irradiation light spreads (the line of intersection between the irradiation surface S3 and the image pickup surface S1 in FIG. 4 is It has, for example, 1024 image sensors (CMOS cells) in the extending direction, and 1280 image sensors (CMOS cells) in the direction orthogonal to the 1024 image sensors. Further, the CMOS image sensor 1732 has a rolling shutter function. The rolling shutter function simultaneously receives only the image sensors arranged in one or more rows (or columns), and sequentially receives the light in each row (or column) in the column direction (or row direction). The method. For example, in FIG. 5, the light receiving of the image sensor (the image sensor highlighted by the thick frame) arranged in the first row is performed at the same time. When this light receiving operation is completed, light reception is sequentially performed in the second row and the third row.

FIG. 6 is a schematic diagram for explaining the imaging region 321 and the observation region 322 of the CMOS image sensor 1732. In the three-dimensional measuring apparatus according to the present embodiment, in the CMOS image sensor 1732, a predetermined area mainly used for imaging the work 5 is an imaging area 321 and the entire area of the CMOS image sensor 1732 including the imaging area 321 is an observation area. When the detailed measurement is performed with 322, the three-dimensional measurement is performed using only the image sensor arranged in the image pickup region 321. This makes it possible to increase the frame rate of the CMOS image sensor 1732. The imaging region 321 and the observation region 322 are regions on the imaging surface of the CMOS image sensor 1732.

FIG. 7 is a block diagram showing a control system of the optical probe 17 according to the present embodiment. The control circuit 174 includes a CPU 1741, a program storage unit 1742 connected to the CPU 1741, a work memory 1743, and a multi-valued image memory 1744. The image information acquired by the CMOS image sensor 1732 is stored in the multi-valued image memory 1744. The CPU 1741 adjusts the light amount of the irradiation optical system 172 via the light amount control unit 1724 with reference to the image information stored in the multi-valued image memory 1744.

Next, the operation of the three-dimensional measuring device configured in this way will be described. As shown in FIG. 4, in the present embodiment, the image pickup apparatus 173 is arranged at a position different from the irradiation surface S3. Therefore, the direction of the irradiation light toward a certain portion of the surface of the work 5 and the direction of the projected light reflected at the portion toward the image pickup apparatus 173 are different. Therefore, for example, if the distance between the optical probe 17 and the work 5 is too close or too far apart, the projected light irradiated on the surface of the work 5 will be out of the imaging range of the imaging device 173, and imaging will be performed. Cannot be done. When confirming from the display of the host system 4 whether or not the projected light is received in the imaging region 321 of the imaging device 173, the operator must visually recognize both the display and the work 5 on the surface plate 11. It causes a decrease in operability.

FIG. 8 is a flowchart for showing the operation of the three-dimensional measuring device according to the present embodiment. In the present embodiment, it is possible to indicate whether or not the projected light is received in the imaging region 321 of the imaging device 173 by the blinking state of the projected light. That is, in the three-dimensional measuring device according to the present embodiment, the work 5 is irradiated with the irradiation light at the time of measurement, and the projected light is imaged in the image pickup area 321 in the image pickup surface of the CMOS image sensor 1732, for example, the image pickup area 321. It is confirmed whether or not the light receiving amount of the image sensor arranged inside exceeds the threshold value (step S101), and among the image pickup elements arranged in the image pickup region 321, the image sensor whose light receiving amount exceeds the threshold value is If it exists, the light emitted from the irradiation optical system 172 is turned on (step S102), and among the image pickup elements arranged in the image pickup region 321 when there is no image pickup element whose light receiving amount exceeds the threshold value. Flashes the light emitted from the irradiation optical system 172 at a predetermined cycle at a light amount visible to the operator (for example, a light amount near 0 and a predetermined light amount) (step S103). In step S101, the determination may be made based on the ratio of all the image pickup elements in the image pickup region 321 whose light receiving amount exceeds the threshold value.

In such an embodiment, the projected light is turned on when the distance between the optical probe 17 and the work 5 is within a distance range in which the projected light projected on the surface of the work 5 by the imaging device 173 can be imaged. Then, when the distance between the optical probe 17 and the work 5 exceeds the distance range, the projected light blinks. Therefore, the operator can confirm whether or not the distance between the optical probe 17 and the work 5 is appropriate only by visually recognizing the state of the projected light applied to the surface of the work 5, and the operability is excellent. It is possible to provide a three-dimensional measuring device. Further, if the distance between the optical probe 17 and the work 5 is not appropriate, the shape of the work 5 cannot be measured. Therefore, even if the light emitted from the irradiation optical system 172 is blinked at such a timing. It does not affect the measurement.

It should be noted that the above-mentioned "lighting" is a state in which the irradiation light or the projected light is continuously emitted from the viewpoint of the operator or the like, and the above-mentioned "blinking" is recognized as blinking when viewed from the operator or the like. It is in a state of being. Therefore, even when the irradiation optical system 172 is controlled by, for example, PWM control, if it can be determined from the operator or the like that the irradiation optical system is continuously emitting light, it is not "blinking" but "lighting". It is assumed that it is.

Further, according to the present invention, since it is not necessary to provide the optical probe 17 with a laser pointer or another illumination light source, it is possible to suppress various problems caused by the above-mentioned heat generation, and by reducing the number of parts. It is also possible to reduce the size and cost of the optical probe 17. Further, since the irradiation optical system blinks in a situation where measurement is impossible, power consumption can be suppressed.

Further, the method according to the present embodiment can be realized at low cost by software, firmware, or the like, and can be applied to an existing three-dimensional measuring device. Further, for example, when the present invention is realized by software or the like and the instruction light emitting unit mounted on the existing device is turned off by the software or the like, the problem due to the above heat also occurs when the existing device is used. It is possible to improve the operability while avoiding the above.

[Second Embodiment]
Next, the three-dimensional measuring apparatus according to the second embodiment of the present invention will be described in detail with reference to the drawings. FIG. 9 is a flowchart for explaining the three-dimensional measurement method according to the present embodiment. In the three-dimensional measurement method according to the present embodiment, the operation mode selection process is first performed (step S1), and the first operation mode (step S2) or the second operation mode (step S3) is set according to the selection operation. It differs in that it is selected to adjust the amount of light of the irradiation optical system 172. The first operation mode is, for example, a manual operation measurement mode in which the probe is manually operated to perform measurement, and the second operation mode is, for example, an automatic operation measurement mode in which the probe is automatically operated to perform measurement. is there. In the first operation mode, the amount of irradiation light described with reference to FIG. 8 is adjusted.

Next, the second operation mode will be described. FIG. 10 is a schematic diagram for explaining the second operation mode. The upper figure of FIG. 10 shows the image captured by the image pickup apparatus 173, and the lower figure shows the relationship between the output of the irradiation optical system 172 and the time in the image pickup cycle for one frame of the CMOS image sensor 1732. In addition, the upper and lower figures correspond to each other, indicating that the images for one row in the upper figure were captured at the time shown in the lower figure using the output of the irradiation optical system 172 shown in the lower figure. There is.

In a three-dimensional measuring device using a triangulation method, for example, when the reflectance or the like differs depending on the location of the surface of the work 5, various problems may occur due to fluctuations in the amount of received light. For example, when the reflectance of a part of the surface of the work 5 is extremely high, the amount of light projected from the surface of the work 5 incident on the CMOS image sensor 1732 is the maximum amount of light capable of suitable imaging. If it exceeds the limit, saturation may occur and the measurement accuracy may be impaired. Further, when the reflectance of a part of the surface of the work 5 is extremely low, the received amount of the projected light incident on the CMOS image sensor 1732 may not reach the threshold value, and the light may not be received. However, in the second measurement mode, as shown in the right portion of FIG. 10, the control circuit 174 adjusts the output of the irradiation optical system 172 according to the amount of light received by the CMOS image sensor 1732. This solves various problems associated with the fluctuation of the amount of received light.

Further, in a three-dimensional measuring device using the triangulation method, for example, when the surface of the work 5 has irregularities of a predetermined value or more, a part of the projected light is not incident on the CMOS image sensor 1732 in the first place, and the portion is not incident on the CMOS image sensor 1732. It may not be able to receive light. In such a case, the control circuit 174 determines that light reception is not performed due to insufficient output of the irradiation optical system 172, raises the output of the irradiation optical system 172 to the maximum value, and may continue to maintain this state. Therefore, there is a risk of deterioration of the light source and increase of power consumption. However, in the second measurement mode, when the CMOS image sensor 1732 does not receive light even though the output of the irradiation optical system 172 is maximum, the left portion of FIG. 10 (the reflected light in the above figure). As shown in the portion where there is no image and the portion where the laser output in the figure below is “0”), the output of the irradiation optical system 172 is minimized to realize a longer life of the light source, lower power consumption, and the like.

FIG. 11 is a flowchart for explaining the operation mode. In the second operation mode, first, one row (or one row) of the CMOS image sensor 1732 receives light, and one-dimensional image information is acquired (S201), and whether or not there is a saturated image sensor is present. Confirm (S202). If there is an image sensor that has been saturated, the output of the irradiation optical system 172 is reduced (S203). If saturation is not detected in step S202, the output of the irradiation optical system 172 is confirmed (S205), and if the output of the irradiation optical system 172 is neither the maximum nor the minimum, at the corresponding position in the next scan. The output of the irradiation optical system 172 of the above is increased (S204). When the output of the irradiation optical system 172 is maximum, it is further confirmed whether or not the amount of light received by the CMOS image sensor 1732 is equal to or less than the threshold value (S206). Here, the minimum measurable light receiving amount may be set as the threshold value. When the amount of light received by the CMOS image sensor 1732 is below the threshold value, the output of the irradiation optical system 172 at the corresponding position at the next scan is minimized (S207), and when it is not below the threshold value, the output of the irradiation optical system 172 is minimized. Leave at maximum. By the above processing, it is possible to minimize the output of the irradiation optical system 172 when measuring the non-detection portion of the work 5, thereby suppressing heat generation, reducing power consumption, and extending the life of the light source. It is possible to plan. When the output of the irradiation optical system 172 is the minimum in step S205, the output of the irradiation optical system 172 at the corresponding position at the time of the next scan is maximized (S208).

The above operation is sequentially performed for each row of the CMOS image sensor 1732 shown in FIG. Although it is conceivable to mainly use the image sensor arranged in the image pickup area 321 in the second operation mode, it is also possible to use the image sensor arranged in the observation area 322.

The output of the irradiation optical system 172 in the non-detection unit may repeat the maximum value and the minimum value for each scan as described above, but for example, n scans are performed while the output of the irradiation optical system 172 remains the minimum. In such a case (n is an arbitrary integer), the maximum value may be switched. Further, the switching from the output minimum value of the irradiation optical system 172 may be an intermediate value between the minimum value and the maximum value instead of the maximum value.

Further, CAD data or the like may be input in advance, and the measurement start position and the measurement end position may be set accordingly. In this case, the CAD data may be input to the host system 4 in advance and stored in the program storage unit 1742 or the like through the drive control circuit 2, or the settings stored in the program storage unit 1742 in advance may be recalled. ..

The three-dimensional measuring device according to the present embodiment can be selectively operated by the first operation mode and the second operation mode. Therefore, for example, when the three-dimensional measuring device is driven by CNC operation, it is conceivable to first teach the three-dimensional measuring device and then automatically operate the three-dimensional measuring device. Here, when teaching, the operator needs to visually recognize the optical probe 17 and the work 5, but the application of the first operation mode eliminates the need to visually recognize the display of the host system 4. Therefore, the operator only needs to visually recognize the optical probe 17 and the work 5, and teaching can be easily performed. On the other hand, when the three-dimensional measuring device is driven by CNC operation, the optical probe 17 is automatically driven according to the teaching result, so that the operator needs to visually recognize the optical probe 17, the work 5, and the like one by one. There is no. Further, in this case, by automatically adjusting the amount of irradiation light, it is possible to perform suitable measurement. Further, it is also possible to switch between the first operation mode and the second operation mode and selectively use the optical probe 17 when the operator operates the optical probe 17, for example, such as teaching.

[Third Embodiment]
Next, the three-dimensional measuring device according to the third embodiment of the present invention will be described with reference to the drawings. The three-dimensional measuring device according to the present invention is basically configured in the same manner as the three-dimensional measuring device according to the first embodiment, but the method for adjusting the amount of light of the irradiation optical system 172 is different.

FIG. 12 is a flowchart for explaining the three-dimensional measuring apparatus according to the present embodiment. In the present embodiment, the work 5 is irradiated with the irradiation light at the time of measurement, it is confirmed whether or not the projected light is received by the image pickup element arranged in the image pickup region 321 (step S301), and the projected light is received. If so, the image sensor 173 is set to the measurement mode (step S302), and the projected light emitted from the irradiation optical system 172 is turned on (step S303). In the measurement mode, the size of the ROI (region for reading an image from the image sensor) of the imaging device 173 is limited to the imaging region 321 and the frame rate is set at high speed.

When the projected light is not received by the image sensor arranged in the image pickup area 321, the image pickup device 173 is set to the observation mode. (Step S304). In the observation mode, the size of the ROI of the image pickup apparatus 173 is set to the maximum (observation area 322), and the frame rate is set to be slower than the frame rate in the measurement mode.

Next, it is confirmed whether or not the projected light is received by the image sensor arranged in the observation area 322 (step S305), and the projected light is received by any of the image pickup elements arranged in the observation area 322. In this case, the projected light is made to blink at a cycle corresponding to the distance between the image pickup region 321 and the image sensor on which the projected light is received (distance on the light receiving surface of the image pickup device 173) (step S306). For example, the closer the projected light is to the imaging region 321 the shorter the blinking cycle, and the farther the image sensor that receives the projected light is from the imaging region 321 is the longer the blinking cycle, and vice versa. , It can be set in various modes that can be visually recognized by the operator.

If the projected light is not received even in the observation area 322, the projected light emitted from the irradiation optical system 172 is blinked at a constant cycle (step S307).

That is, in the three-dimensional measuring apparatus according to the present embodiment, the blinking cycle of the projected light is adjusted by the distance between the image pickup region 321 and the image pickup device that has received the projected light on the image pickup surface. Therefore, the operator can more easily adjust the distance between the optical probe 17 and the work 5 according to the blinking cycle of the projected light.

When the projected light is received in the imaging range 321, it is possible to perform suitable measurement by performing CMOS imaging at a high frame rate. Further, normally, when an image sensor outside the imaging range 321 is not used for measurement, the frame rate is set when the projected light is not received in the imaging range 321 and the projected light is received in the observation range 322. Lowering it does not affect the measurement.

[Fourth Embodiment]
Next, the three-dimensional measuring device according to the fourth embodiment of the present invention will be described. A Scheimpflug optical system has been adopted for the three-dimensional measuring apparatus according to each of the above embodiments. However, it is not always necessary to adopt the Scheimpflug optical system. In this embodiment, a telecentric optical system is used. For example, as shown in FIG. 13, an image pickup device 173'a and an image pickup device 173' formed by arranging the main plane S2'including the main points of the image pickup surface S1'and the lens 1731b' of the CMOS image sensor 1732 or the CCD image sensor in parallel. (More preferably, the visual field range of the light receiving element arranged in the imaging region 321), and the irradiation light is irradiated along the plane S3'passing through the region which is the focusing range of the lens 173b'. It is also possible to adopt an irradiation optical system 172'. When the optical system is adopted, the depth of focus of the lens 1731b'in FIG. 13 should be larger than the depth of focus of the lens 1731b in FIG. 4 in order to focus on the projected light projected on the surface of the work 5. Can be considered. Even when this configuration is used, it is possible to preferably perform three-dimensional measurement by the principle of triangulation.

[Other Embodiments]
In each of the above embodiments, the imaging device 173 uses a CMOS image sensor, but other imaging devices such as a CCD image sensor can also be adopted. It is also possible to use the second operation mode and the first operation mode in the second embodiment together. In this case, for example, when the output of the irradiation optical system 172 is maximum and the amount of light received is equal to or less than the threshold value for all the image pickup elements, it is determined that the distance between the optical probe 17 and the work 5 is inappropriate. It is also conceivable to blink the irradiation light. Further, for example, when the three-dimensional measuring device has another configuration (camera, sensor, etc.) capable of recognizing the position of the optical probe 17, the distance between the optical probe 17 and the work 5 is recognized by the other configuration. It is also possible to let it.

Further, in each of the above embodiments, the work 5 is arranged on the surface plate 11 and is optically operated by the arm supports 12a and 12b, the X-axis guide 13, the Y-axis drive mechanism 14, the Z-axis guide 15 and the Z-axis arm 16. The position of the formula probe 17 is controlled. However, the present invention is not limited to such an embodiment, for example, a three-dimensional measuring device in which an optical probe 17 is attached to the tip of an articulated arm, a robot arm, or the like, or a camera or the like that positions the optical probe 17. It can be applied to various aspects as long as it is a three-dimensional measuring device that acquires the positions of the optical probe 17 and the work 5 by using a triangulation method, such as a three-dimensional measuring device that is acquired by another configuration. is there.

Further, in each of the above embodiments, the light emitted from the light source is spread by a cylindrical lens or the like to generate the irradiation light along the predetermined plane S3, but the irradiation light along the predetermined plane S3 is generated. Can also be generated, for example, by scanning the light from a light source with a scanning mirror (galvano mirror, polygon mirror, etc.). In the case where the scanning mirror generates the irradiation light along the predetermined plane S3 and the CMOS image sensor is adopted as the image pickup apparatus 173, the scanning cycle of the irradiation light and the imaging of the CMOS image sensor are performed. It is conceivable to synchronize with the cycle.

1 ... 3D measuring device, 2 ... Drive control device, 3 ... Operation panel, 4 ... Host system, 10 ... Vibration isolation table, 11 ... Plate, 12a, b ... Arm support, 13 ... X-axis guide, 14 ... Y-axis drive mechanism, 15 ... Z-axis guide, 16 ... Z-axis arm, 17 ... optical probe, 171 ... housing, 172 ... irradiation optical system, 173 ... imaging device, 174 ... control circuit, 321 ... imaging area, 322 ... Observation area, 1721 ... Laser light source, 1723 ... Beam expander, 1724 ... Light amount control unit, 1731 ... Optical system, 1732 ... CMOS image sensor, 1741 ... CPU, 1742 ... Program storage unit, 1743 ... Work memory, 1744 ... Many Value image memory, 1731a ... bandpass filter, 1731b ... lens.

Claims (6)

A three-dimensional measuring device that measures the surface shape of a work by scanning the surface of the work with a non-contact probe.
The probe
An irradiation optical system that irradiates the work with irradiation light along a predetermined plane,
An image pickup device that has a plurality of image pickup elements arranged on an image pickup surface and images the work from a position different from that on a predetermined plane.
A control unit for controlling the illumination optical system in accordance with an output signal of said imaging device,
The irradiation optical system and the housing for accommodating the imaging device are provided.
The control unit
A step of determining whether or not an image sensor arranged in a predetermined image pickup region on the image pickup surface has detected the projected light projected on the surface of the work by the irradiation light from the irradiation optical system.
When the image pickup element arranged in the image pickup region detects the projected light, the step of turning on the irradiation light emitted from the irradiation optical system and measuring the work.
When the image pickup device arranged in the image pickup region does not detect the projected light, the step of blinking the irradiation light emitted from the irradiation optical system at a predetermined cycle is repeated. measuring device. The control unit
When there is an image sensor whose light receiving amount exceeds the threshold value among the image sensors arranged in the image pickup region, it is determined that the image sensor arranged in the image pickup region detects the projected light. ,
If there is no image sensor whose light receiving amount exceeds the threshold value among the image sensors arranged in the image pickup area, it is determined that the image sensor arranged in the image pickup area does not detect the projected light. The three-dimensional measuring device according to claim 1, wherein the three-dimensional measuring device is characterized. The control unit
The distance between the probe and the work is detected by the position of the image sensor that detects the projected light in a predetermined observation region wider than the predetermined imaging region on the imaging surface.
When the image pickup device arranged in the image pickup region does not detect the projected light, the irradiation light emitted from the irradiation optical system is blinked at a cycle corresponding to the detected distance. Item 3. The three-dimensional measuring device according to item 1 or 2. An observation area wider than the predetermined image pickup area is provided on the image pickup surface of the image pickup device.
When the image sensor arranged in the image pickup region does not detect the projected light, the control unit acquires the distance from the image sensor in the observation area where the projected light is detected to the image pickup region. The three-dimensional measuring device according to claim 1 or 2, wherein the irradiation light emitted from the irradiation optical system is blinked at a cycle corresponding to this distance. An observation area wider than the predetermined image pickup area is provided on the image pickup surface of the image pickup device.
The control unit
When the image sensor arranged in the image pickup area detects the projected light, the image is read out from the predetermined image pickup area.
The three-dimensional measuring apparatus according to claim 1 or 2, wherein when the image pickup device arranged in the image pickup region does not detect the projected light, an image is read out from the observation region. The control unit
When the image pickup device arranged in the image pickup region detects the projected light, the frame rate of the image pickup device is set to the first frame rate.
When the image sensor arranged in the image pickup region does not detect the projected light, the frame rate of the image pickup device is set to a second frame rate slower than the first frame rate. The three-dimensional measuring device according to claim 5.

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