JP3511806B2 - 3D measuring device - Google Patents

Description

Description: BACKGROUND OF THE INVENTION [0001] 1. Field of the Invention
Non-contact measurement of object shape by irradiating detection light represented by
To a three-dimensional measuring device. [0002] A non-contact type called a range finder
Three-dimensional measuring device (three-dimensional camera)
Because high-speed measurement is possible, CG systems and CA
Data input to D system, body measurement, robot vision
It is used for recognition. [0003] As a measuring method suitable for a range finder,
The slit light projection method (also called the light cutting method) is known.
You. This method is based on the optical scanning of objects and the basis for triangulation.
Is a method of obtaining a distance image (three-dimensional image) based on the
Of an active measurement method that captures an object by irradiating detection light
It is a kind. The distance image is a three-dimensional image of multiple parts on the object
It is a set of pixels indicating a position. In slit light projection,
Slit light having a straight section is used as the detection light.
Spot light, step light, density pattern
A light projection method for projecting a turn light or the like is also known. Conventionally, the photographing distance can be arbitrarily selected.
The portable range finder measures the distance between the objectives and
Focusing (AF) function to set the focus position
(Japanese Patent Application Laid-Open No. 7-174536). Measurement
The distance information thus set is also used for setting the amount of projection light. SUMMARY OF THE INVENTION [0005]
Using an optical system for measurement
Distance measurement can be performed. It also has scanning means
Therefore, by irradiating detection light in multiple directions, the viewing angle of distance measurement
It is easy to spread. On the other hand, the range finder periodically
By providing the function to perform, the application range of three-dimensional measurement
spread. For example, shape inspection of goods on a production line of a factory
Inspection, visual recognition of mobile robots, security monitoring system, etc.
Can be more practical. With periodic 3D measurement
By comparing the obtained time series of distance images,
The longitudinal movement and the shape change can be easily distinguished. [0007] However, during measurement, avoid changes in shooting conditions.
Therefore, it is necessary to prohibit lens movement. For this reason,
In the distance measurement using the optical system for measurement,
The distance between the objects cannot be measured because the object moves during measurement.
Distance measurement system loses track of object when distance changes significantly
There was a problem. Set measurement conditions if you lose track
(Focusing, light intensity setting, etc.)
Cannot be performed, and the reliability of the setting is reduced. Also, when out of focus
When the measurement is performed, the accuracy of the distance image decreases. Once, the object
If you lose track of the object, you can change the
Even if you try, you can catch the object with one-way projection
Switching the projection direction to catch objects, not necessarily
May be necessary and the ranging may stagnate.
You. [0008] The present invention provides a method for performing periodic measurement.
To improve the reliability of setting measurement conditions
You. Means for Solving the Problems An optical system for measurement is used.
Both the distance measurement by the light projection method and the distance measurement by the distance measurement sensor are used.
Use. Accuracy of measurement by using optical system for measurement
And continuous measurement is performed by the distance measurement sensor. Ranging
The sensor is wider than the target range for distance measurement by the light projection method.
Use a device that can measure in a wide range. Obtained with a distance measurement sensor
If you select the projection direction with reference to the measured value, the efficiency
Distance measurement by the light projection method can be performed effectively. The apparatus according to the first aspect of the present invention irradiates a detection light.
Light projecting means for optically scanning an object by
Imaging means for receiving the detection light reflected by the
A three-dimensional measuring device that measures the shape of an object by the projection method.
Distance measuring sensor that outputs a signal corresponding to the distance between the objectives
When, Measured by light projection Measure according to the distance between the objectives
Control means for setting measurement conditions.
Measurement by light projection method as operation mode Is Object distance
After setting measurement conditions according to the distance, the output of the distance measurement sensor
Monitor the force and if the output change exceeds the allowable value
The projection direction is determined based on the output of the distance measurement sensor.
The distance between the objects is increased by the light projection method. again Measure and the result
Mode to reset measurement conditions based on
It is. FIG. 1 shows a measuring system according to the present invention.
1 is a configuration diagram. The measurement system 1 is a slit light projection
3D camera (Range-fi
2) and a camera for processing output data of the three-dimensional camera 2.
And a strike 3. The three-dimensional camera 2 includes a plurality of suns on the object Q.
Measurement data to specify the three-dimensional position of the pulling point (distance map
Image) together with a two-dimensional image showing the color information of the object Q.
And output data necessary for calibration. triangle
Calculation processing to find the coordinates of sampling points using surveying method
Is carried by the host 3. The host 3 includes a CPU 3a, a display 3
b, keyboard 3c, mouse 3d, etc.
Computer system. The measurement data is stored in the CPU 3a.
Data processing software is installed. E
Between the strike 3 and the three-dimensional camera 2
Data transfer is performed. FIG. 2 is a view showing the appearance of the three-dimensional camera 2.
You. A light emitting window 20a and a light receiving window 2 are provided on the front of the housing 20.
0b is provided. The light emitting window 20a is connected to the light receiving window 20b.
It is located on the upper side. Internal optical unit OU emits
Slit light (a band-shaped laser beam having a predetermined width w) U
Is transmitted to the object (subject) to be measured through the light emitting window 20a.
Heading. The radiation angle φ in the length direction M1 of the slit light U is fixed.
It is fixed. Part of the slit light U reflected on the surface of the object
The light enters the optical unit OU through the light receiving window 20b. light
Unit OU properly adjusts the relative relationship between the emitting axis and the receiving axis
And a two-axis adjustment mechanism. On the upper surface of the housing 20, a zooming
Tons 25a, 25b, manual focusing button 26
a, 26b and start / stop button 27
Have been. As shown in FIG.
On the surface, a liquid crystal display 21, a cursor button 22,
Select button 23, cancel button 24, analog
Output terminals 31 and 32 and digital output terminal 33 are provided.
Have been. From the analog output terminal 31, measurement data
And the distance image DG is output.
Output a two-dimensional image DM. Output of analog signal
The format is, for example, the NTSC format. Digital output terminal 3
Reference numeral 3 denotes, for example, an RS232-C terminal,
Used for DS output. A liquid crystal display (LCD) 21 operates
It is used as a screen display means and an electronic finder.
The photographer can set the shooting mode by using the buttons 22 to 24 on the back.
Can be set. FIG. 3 is a block diagram showing the functional configuration of the three-dimensional camera 2.
It is a lock figure. Solid arrows in the figure indicate the flow of electrical signals.
The dashed arrows indicate the flow of light. 3D camera 2
Is a light-emitting side and a light-receiving side constituting the optical unit OU described above.
It has two optical systems 40 and 50 on the side. Optical system 40
, The wavelength 6 emitted by the semiconductor laser (LD) 41
The 70 nm laser beam passes through the projection lens system 42
The slit light U, and the galvanomirror
(Scanning means) 43. Semiconductor laser 4
1; a driver 44; a driving system 45 of the projection lens system 42;
The drive system 46 of the galvanomirror 43 is
Controlled by the roller 61. In the optical system 50, a zoom unit 51
Is collected by the beam splitter 52.
It is split. The light in the oscillation wavelength band of the semiconductor laser 41 is
The light enters the sensor 53 for measurement. Light in the visible band
Incident on the color sensor 54 for the color filter. Sensor 53 and power
Color sensors 54 are both CCD area sensors.
You. The zoom unit 51 is a focus type, and a part of the incident light.
Are used for auto-focusing (AF). AF machine
The structure is a passive system used in single-lens reflex cameras.
Yes, the AF sensor 57, lens controller 58 and
And a focusing driving system 59. Zoomin
The driving system 60 is provided for electric zooming.
You. For passive distance measurement by the AF sensor 57,
Measurable distance compared to the active distance measurement described
It is possible to repeat the measurement in a short period with a wide range
There are advantages. However, the passive range finding accuracy (decomposition
Noh) is not enough. The information captured by the sensor 53 is transmitted to the driver 5
5 to the output processing circuit 62 in synchronization with the clock from
It is. For each pixel of the sensor 53 by the output processing circuit 62
Is generated and stored in the memory 63.
Will be delivered. Thereafter, the slit data is read from the memory 63.
It is extracted and sent to the center-of-gravity calculation circuit 64. Center of gravity calculation circuit
64 is a high-resolution distance image based on slit data
Generate The distance image passes through the NTSC conversion circuit 65.
Measurement data in the form of a frame-synchronous video signal.
Output online. The center of gravity calculation circuit 64 includes a system
Bit data for control by the system controller 61
CTRL register R1 for storing (GCALC) is provided
Have been. On the other hand, image pickup information by the color sensor 54
Performs color processing in synchronization with the clock from the driver 56.
Transferred to the circuit 67. Color-processed imaging information
(Two-dimensional image DM) is transmitted to the NTSC conversion circuit 70 and the analog
The data is output online through the log output terminal 32. 2D
The image DM has the same angle of view as the distance image obtained by the sensor 53.
It is a color image and the application on the host 3 side
It is used as reference information during processing. It should be noted that the system controller 61
On the screen of the LCD 21 with respect to the lactator generator 71
Displays the appropriate characters and symbols according to the current operating state
Give instructions to do. FIG. 4 shows a three-dimensional position in the measurement system 1.
It is a principle diagram of calculation of. On the imaging surface S2 of the sensor 53,
A relatively wide slit light U corresponding to several pixels is converted into an object Q.
Irradiation. Specifically, the width of the slit light U is set to 5 pixels.
I do. The slit light U is applied to the imaging surface S every sampling cycle.
2 from top to bottom so as to move by one pixel pitch pv on
The object Q is scanned.
One field from the sensor 53 for each sampling cycle
The photoelectric conversion information is output. Focusing on one pixel g on the imaging surface S2,
5 samples out of N samples performed during scanning
In this case, effective light receiving data can be obtained. These five times
The target pixel g
The optical axis of the slit light U passes through the object surface ag in the range of glare.
Timing (time centroid Npeak: of the pixel of interest g)
The time at which the amount of received light is maximized) is determined. In the example of FIG.
Is the time between the nth time and the previous (n-1) th time.
The received light amount is the largest in the ringing. The calculated time center of gravity Npeak
Direction of the slit light at
The position of the object Q based on the relationship with the incident direction of the lit light
(Coordinates). Thereby, the pixel pitch of the imaging surface
Measurement with higher resolution than the resolution specified by pv is possible
Become. The irradiation direction of the slit light is the same as the irradiation start direction.
If the deflection angular velocity is known, the time center of gravity Npeak is used.
Is uniquely identified. The incident direction is the sensor 53
It is specified by the positional relationship information between the camera and the light receiving lens. The amount of light received by the target pixel g depends on the reflectance of the object Q.
Exist. However, the relative amount of each received light amount of 5 samplings
The ratio is constant regardless of the absolute amount of received light. In other words, the object
Color shading does not affect measurement accuracy. In the measuring system 1 of the present embodiment, the three-dimensional
The pixel of the sensor 53 is calculated by the center-of-gravity calculation circuit 64 of the camera 2.
When the time center of gravity Npeak is calculated for each g and the number of effective pixels
The center of gravity Npeak is used as a distance image in NTSC format.
Transmitted to port 3. Thereby, light reception for 5 fields
Data is sent to the host 3 and the time center of gravity Np is
transmission data volume is significantly smaller than when eak is determined.
Time required for serial transmission using analog signals
Can be shortened. The time center of gravity Npeak
And equipment conditions required to determine the coordinates of the object
Is connected to the digital output terminal 33 in parallel with the transmission of the distance image.
Is transmitted to the host 3 via the. FIG. 5 shows the output processing circuit 62 and the memory 63.
FIG. 6 is a block diagram showing the reading range of the sensor 53.
is there. The output processing circuit 62 outputs the photoelectric signal output from the sensor 53.
AD converter that converts the conversion signal to 8-bit light reception data
620, four delay memories 621 to 621 connected in series
624, comparator 626, and field number
(Sampling number) Generator 62 indicating FN
7. The memory 63 has 5 effective
To store the received light data (slit data)
Of the five memory banks 63A to 63E,
Bank for storing field number FN
63F and address designation of the memory banks 63A to 63F.
And a memory control means (not shown) for performing
You. Each of the memory banks 63A to 63E is used for sampling of measurement.
The same number of received light as the number of points (that is, the number of effective pixels of the sensor 53)
It has a capacity to store data. Data is stored in the four delay memories 621 to 624.
By performing the data delay, it is possible to obtain 5 pixels for each pixel g.
At the same time as the memory bank 63A-
E can be stored. The sensor 5
Reading of one field in 3 is performed on the entire imaging surface S2.
However, in order to increase the speed, as shown in FIG.
Of the effective light receiving area (band image) Ae
Will be The effective light receiving area Ae is accompanied by the deflection of the slit light U.
Shift by one pixel for each field. This embodiment
Then, the number of pixels in the shift direction of the effective light receiving area Ae becomes 32.
Fixed. A part of the captured image of the CCD area sensor
The method of reading only the data is described in Japanese Patent Application Laid-Open No. 7-174536.
It has been disclosed. The AD conversion unit 620 outputs 3
The received light data D620 for two lines are arranged in the arrangement order of the pixels g.
Realistic output. Each delay memory 621 to 624
Is a FIFO having a capacity of 31 (= 32-1) lines
It is. The pixel of interest output from the AD converter 620
g of received light data D620 is delayed by two fields.
At that time, the comparator 626 activates the memory bank.
In the past received light data for the pixel of interest g stored in the
Data D620. Delayed receiving data
Data D620 (output of delay memory 622)
If the value is larger than the maximum value, the AD converter 620 at that time
And the outputs of the delay memories 621 to 624 are
Memory banks 63E, 63D, 63C, 63B, 63A
And stored in the memory banks 63A to 63E.
The contents are rewritten. At the same time, the memory bank 63F
Is the received light data D620 stored in the memory bank 63C.
Is stored as the field number FN. That is, the n-th (n <N) field
When the received light amount of the pixel of interest g is maximized,
The data of the (n-2) th field is stored in the bank 63A.
And stored in the memory bank 63B.
Field data is stored in memory bank 63C.
The data of the first field is stored in the memory bank 63
D stores the data of the (n + 1) th field,
The data of the (n + 2) th field is stored in the memory bank 63E.
Is stored in the memory bank 63F.
You. FIG. 7 is a block diagram of the center-of-gravity calculating circuit 64.
You. The center-of-gravity calculation circuit 64 includes five multipliers 641 to 64
5, a total of three adders 646 to 648, a divider 649, and
And a delay circuit 640. (N-2) to (n +
2) 5 field numbers (that is, when sampling
Time) are weighted -2, -1, 0, 1, 2, respectively.
Addition to the received light data from each of the memory banks 63A to 63E.
Perform a weighted average calculation. Weighted average output of divider 649
The values are the nth sampling time and the time centroid Npeak
(See FIG. 4B). This time
Deviation and field number from memory bank 63F
By adding FN, the time barycenter Npeak is obtained. Late
The extension circuit 640 determines the field number at the same time as the time shift amount.
Provided to input the FN to the adder 648;
Delay field number FN by the time required for weighted average calculation
Extend. Corresponding to each pixel from memory banks 63A-F
The read data is sequentially read and input to the centroid operation circuit 64.
By this, the distance image DG which is the measurement information for one time is
Generated. The distance image DG is, for example, 30 times per second.
It is output repeatedly in a cycle. Next, a basic method of measurement by the three-dimensional camera 2
The order will be described. In the measurement system 1, the three-dimensional camera 2
The arrangement relationship with the measurement target is variable. That is, the user
Is to change the shooting distance and angle appropriately according to the application
Can be. For this reason, prior to measurement,
Pre-processing for setting the shooting conditions by checking the positional relationship (shooting preparation)
Is done automatically. FIG. 8 shows the relationship between each point of the optical system and the object Q.
FIG. Direct operation or three-dimensional camera 2
A zooming instruction is given by remote control by the host 3.
When the variator of the zoom unit 51 moves
Focusing by moving the focusing unit
Done. Approximate objective distance during focusing
Separation d ₀ Is measured. For driving such a light receiving system lens
In response, the calculation of the amount of movement of the variator lens on the projecting side is
And lens movement control is performed based on the calculation result.
You. However, during shooting, the shooting conditions
Zooming and focusing to avoid changes
Is forbidden. The system controller 61 includes a lens controller.
The focusing drive system 59 is driven through the
Encoder output (feed amount Ed) and zooming drive system
Read 60 encoder outputs (zoom increment fp)
No. In the system controller 61, distortion correction
The difference table, principal point position table, and image distance table
Referenced and corresponds to the feed amount Ed and zoom increment value fp
The obtained photographing condition data is output to the host 2. Here
The photographing condition data includes a front principal point position, an image distance, and the like. The system controller 61 includes a semiconductor
Of the output (laser intensity) of the body laser 41 and the slit light U
Calculate deflection conditions (projection start angle, projection end angle, deflection angular velocity)
Set. First, the approximate distance between the objects d ₀ On a flat object
Assuming that the body exists, the reflected light is
Set the projection angle to receive light. Next, calculate the laser intensity.
Set. Semiconductor with minimum strength in consideration of human safety
Lights the laser 41 in pulses and captures the output of the sensor 53
No. The projection angle at this time is the distance d ₀ On the basis of the
The set angle. Between the captured signal and the appropriate level
The ratio is calculated, and a temporary laser intensity is set. Set temporary
The pulse is turned on again at the laser intensity, and the output of the sensor 53 is taken.
Embed. Until the output of the sensor 53 becomes a value within the allowable range.
Then, the temporary setting of the laser intensity and the confirmation of suitability are repeated. What
When the received light intensity is insufficient even when lit at the maximum intensity
Performs exposure control to extend the charge accumulation time of the sensor 53.
U. Subsequently, the projection angle and the light receiving position of the slit light U
Then, the distance d between the objects is determined by triangulation. Soshi
Finally, based on the determined inter-object distance d, the deflection
Calculate the condition. When calculating the deflection conditions,
The rear principal point H ′ of the light receiving system, which is the distance measurement reference point at a distance d, is
An offset doff from the starting point A is considered. Also scanning
The same measurable distance range as the center at the end in the direction
To secure d ', a predetermined amount (for example, for 8 pixels) of
Perform a bar scan. The projection start angle th1
The firing end angle th2 and the deflection angular velocity ω are represented by the following equations. Th1 = tan ^-1 [Β × pv (np / 2 +
8) + L) / (d + doff)] × 180 / π th2 = tan ^-1 [−β × pv (np / 2 + 8) + L)
/ (D + doff)] × 180 / π ω = (th1−th2) / np β: imaging magnification (= d / effective focal length freal) pv: pixel pitch np: number of effective pixels in the horizontal direction of the imaging surface S2 L: base line Actual measurement is performed under the conditions calculated in this way.
Device information including the specifications of the sensor 53 and the shooting conditions
Transmission from the 3D camera 2 to the host 3 together with the separated image DG
Is done. However, in the continuous mode described later,
In other words, the device information is transmitted only at the time of the first measurement. Table 1
Summarizes the main data that the 3D camera 2 sends to the host 3.
It is a thing. [Table 1] Hereinafter, the operation of the measurement system 1 will be described in more detail. The operation of the three-dimensional camera 2 corresponds to a start instruction.
One-shot mode in which measurement is performed only once in response,
After receiving the start instruction, the lap
Continuous mode for continuous measurement (continuous shooting mode)
). AF mode in continuous mode
As modes, there are a variable mode and a fixed mode. Variable mode
During the period excluding measurement, the AF sensor 57
In this mode, focusing is performed according to the force. Fixed module
Mode performs focusing only during the first measurement.
Mode. AF sensor in either mode
The measurement of the distance between the objects by 57
Will be implemented. When the magnification of shooting is large (telephoto state)
Provides a clear range image because defocus is likely to occur.
Variable mode is suitable above. Also, depending on the variable mode
For example, if the object moves greatly,
Can be On the other hand, according to the fixed mode,
The drive control can be omitted. FIGS. 9 and 10 show continuous mode.
Is a time chart showing the operation of the three-dimensional camera 2 in FIG.
is there. Table 2 shows the contents of the control signals. [Table 2] Here, the system controller 61 is focused on
Explain the work. [1] Turn on the start / stop button 27
In response to a start command input from the
Then, shooting preparation (pre-processing) is started. Preparation for shooting
As described above, the object distance d is obtained by the light projection method, and
Active AF (A-AF) / Projection angle setting / Laser intensity
This is processing for performing settings and the like. [2] When the photographing preparation is completed, the CTRL
The RUN bit of the register R1 is set to 1. And SSt
Wait for the art bit to become 1. [3] First VSync after RUN bit becomes 1
The SStart bit is set to 1 in response to
Reset the frame counter. The SStart bit is
The value is returned to 0 at the next VSync. [4] [5] SStart bit becomes 1
Lens movement is prohibited to fix the shooting conditions,
Start scanning (photographing) of the object with the cut light U
You. During the period of about 0.8 seconds thereafter, the system
Controller 61 is dedicated to scanning control, lens
The controller 58 executes the distance measurement by the AF sensor 57
I do. In this distance measurement, the next scan
Predict the distance between objectives at the start of canning
You. [6] [7] When scanning is completed,
The GCALC bit of the CTRL register R1 is set to 1.
In response to this, the center-of-gravity calculating circuit 64 sets the time center of gravity Npeak.
The calculation of is started. The GCALC bit is the distance image DG
Is completed by the center-of-gravity calculation circuit 64 when the generation of
Set. The lens is moved to the lens controller 58.
Allow the movement to resume. In response, the lens control
The lens 58 measures the inter-object distance with the AF sensor 57.
Start passive AF (P-AF) for lens movement
You. [8] [9] The GCALC bit becomes 0
In response to the first later VSync, the NextI bit is set to 1
And switch the frame memory to
The output of the separated image DG is started. After this, the next scan
Is performed until a new distance image DG is generated.
The distance image DG having the same content is repeatedly output. Next
The I bit returns to 0 at the first VSync after being set to 1.
You. [10] A port (data) different from the distance image DG
From the digital output terminal 33).
Output to strike 3. The host 3 receives this signal,
It recognizes that the latest distance image DG has been output.
When the specified data output is completed,
To calculate the distance and exposure conditions for the next shot.
And wait until the SStart bit becomes 1. In addition,
At this stage, if the above variable mode
The change in the distance between the objectives is detected based on the output of the black AF.
And when the distance between the objectives exceeds the allowable value
High-precision distance measurement using the light projection method
Calculate focusing and shooting conditions. [11] When the count value of the frame counter is
When the value reaches one less than the designated value (OPR), the next V
Reset the count value with Sync, and
Set the art bit to 1. SS at the next VSync
Set the start bit back to 0. The OPR is on the host side.
Set manually. In other words, the user sets the desired measurement cycle
Can be set. [12] [13] SStart bit is set to 1
If this happens, the lens movement is prohibited and scanning is performed as in [4] and [5].
Start the shooting. After that, [6]-[1
1], and every time the SStart bit becomes 1
Then, the measurement operations [3] to [11] are repeated. However,
In the second and subsequent measurements counted from the start instruction,
Output of device information is omitted. [14] [15] As shown in FIG.
Turn on the start / stop button 27 or from the host 3
The RUN bit is set to 0 in response to the input of the stop command.
Return to When the stop instruction is issued during the center of gravity calculation
Resets the GCALC bit to 0 at that time. At what point
Even if a stop instruction is given, the distance image obtained last
The output of the DG is continued. FIG. 11 shows the third order in the one-shot mode.
6 is a time chart illustrating the operation of the original camera 2. [21] to [29] Enter the continuous mode described above.
The same operation as [1] to [9] is performed. [30] When the NextI bit becomes 1,
Reset the RUN bit to 0. [31] Photographing conditions and device from digital output terminal 33
The information is output to the host 3. After that, a start instruction is given
Until the new range image DG is obtained.
The output of the distance image DG is continued. FIG. 12 shows the system controller of the three-dimensional camera 2.
6 is a main flowchart of the operation of the roller 61. Power supply
Is input, the bit of the CTRL register R1 is included.
Initial setting of control parameters is performed (# 1). Button operation
Or, set the mode according to the command from the host 3.
(# 2). At this time, the user
Set the measurement cycle in the mode in frame units
Can be. When the start instruction is received, the operation moves to the measuring operation.
(# 3). If the AF mode is the variable mode, the first scan
Execute the sequence (# 4, # 5)
For example, the second scan sequence is executed (# 6). FIG. 13 shows the first scan sequence and the second scan sequence.
6 is a flowchart of a scan sequence. FIG.
In the first scan sequence as shown in FIG.
Start the sib AF, and move the object relative to the three-dimensional camera 2.
The focusing lens position according to the movement
(# 51). When receiving a start instruction,
Stop passive AF to prevent lens movement during
To stop and prohibit zooming (# 52, 5
3). Scanning for obtaining distance image DG
Executes processing, and after scanning ends, passive AF
And cancel the ban on zooming (#
54-56). After receiving command input and operation,
The count value of the frame synchronization signal VSync reaches the set value
To check whether the end is appropriate (# 57-5)
9). In one shot mode or continuous
When the end instruction is received in the
Return to Chin. In continuous mode
If there is no end instruction, the flow returns to step # 52 to repeat the measurement.
Return. On the other hand, as shown in FIG.
In the sequence, first, passive AF is started,
Upon receiving the instruction, the passive AF is stopped and zoom
Is prohibited (# 61 to # 63). Scanning process
Is executed, the prohibition of zooming is released (# 64,
65). Passive AF does not resume. Command input and
Accepts the operation and counts the frame synchronization signal VSync.
Wait for the default value to reach the set value and check the end
(# 66- # 68). In one shot mode,
Indicates that a termination instruction has been received in continuous mode.
If so, the process returns to the main routine. Continue
If there is no end instruction in the sleep mode, step # 63
Return to and repeat the measurement. FIG. 14 shows the scanning process (#) in FIG.
54 and # 64). As mentioned above
The distance to the object (object to be measured)
57 at all times. This distance (object distance)
Check the amount of change in the distance, and if the amount of change exceeds the
In this case, use the slit light projection method to find the distance between the objectives and shoot
A setting process for determining conditions is executed (# 100, 10
1). Even if the change does not exceed the tolerance,
During the first measurement in response to the
Execute (# 102). In other words, in principle, from the second time
Setting process (# 100) is omitted in the measurement of
The setting process is executed only when there is a large change in. This
As a result, the accuracy of three-dimensional measurement is ensured, and the burden of control is reduced.
It is reduced. Photographing conditions in continuous mode
If the distance calculation mode is specified as the setting mode for
In such a case, the distance image DG is obtained under the shooting conditions at that time.
After executing the running control,
To calculate the shooting conditions for the next measurement.
To calculate the projection angle and the amount of slit light (#
103-106). Also, if the brightness calculation mode is specified
If scanning is
The lit light amount is calculated (# 107 to # 109). Rangefinder
Calculation mode and brightness calculation mode are not specified.
In the one-shot mode,
Execute the running control and return to the main routine
(# 103, 107, 110). The next measurement is taken based on the immediately preceding photography information.
Preliminary measurement is performed for each measurement by calculating shadow conditions
Required for preliminary measurement compared to calculating shooting conditions
The measurement cycle can be shortened by the interval. In addition, measurement
Will give you detailed information on the space of the scanning range.
Use the measurement information of the next as preliminary measurement information of the next measurement
In such a case, for example, a preliminary projection of the slit light U in one direction is performed.
More accurate calculation of shooting conditions than measurement
It is possible. FIG. 15 is a flowchart for calculating the projection angle.
It is. First, the distance image is analyzed and the representative value of the inter-object distance is calculated.
Is determined (# 1051). The decision method is as follows
There are various methods including Pixels are sampled uniformly from the whole image
The shortest distance is set as a representative value. According to this, the image
It is possible to avoid errors that represent the distance of the background part inside as a representative value.
it can. A plurality of images arranged vertically and horizontally near the center of the image
Sample the elementary values and represent the average or intermediate value of the distance as the representative value
And This method also has the advantage of being less affected by noise.
One. Is a method that combines
Sample multiple pixels lined up vertically and horizontally from each divided area
It is something to do. Next, device conditions such as a representative value and a pixel pitch will be described.
And triangulation based on shooting conditions such as focal length
The actual distance is obtained by applying the principle of (# 1052).
Then, a predetermined range before and after the position of the obtained distance is a measurement target.
The starting angle of the projection in scanning
And the end angle. FIG. 16 is a flowchart for calculating the amount of slit light.
It is. The memory bank 63C of the memory 63 stores
Uniform light reception data (reflected light amount) in the nth field
And the largest sampled value is the representative value
And At this time, the largest sampling value is the upper limit
, That is, the amount of light received by the measurement sensor 53 is saturated.
, The attention of the (n ± 1) th field
Maximum light quantity by interpolation calculation based on light receiving data of pixels
And the result is set as a representative value (# 1061). Next, according to the representative value, the measuring sensor 53
Set the slit light amount so that the
Is increased or decreased (# 1062). At this time, if necessary,
At the time of exposure of the measurement sensor 53 together with the adjustment of the lit light amount
By adjusting the interval, the amount of received light is optimized. FIG. 17 is a flowchart of the setting process of FIG.
It is. Designation of shooting distance by operation or command input
If there is no, irradiate slit light U and based on shooting information
To obtain the distance between the objectives, and a predetermined range around the position of the obtained distance.
So that the surrounding area becomes the measurement target.
Set the start angle and end angle of the shooting (# 1011-1
015). And if there is no designation of slit light amount,
Optimal amount of light received by measurement sensor 53 based on shooting information
Increase or decrease the set value of the slit light amount so that the value becomes
015, 1019). When the photographing distance is specified and the slit light amount
If not specified, illuminate with slit light U
The set value of the slit light amount is increased or decreased based on the
-1019). FIG. 18 is a flowchart of the measurement processing of the host 3.
It is. Start command for 3D camera 2
And waits for input of shooting condition data DS (# 31,
32). In response to the input of the photographing condition data DS, the distance
The separated image DG is captured as one measurement information (# 3
3). Then, information processing for the distance image DG is performed.
(# 34). This information processing includes the distance image DG and
Coordinate calculation based on shadow conditions and storage of distance image DG
And so on. Predetermined termination conditions (time,
Shooting condition data until the acquisition number end operation) is satisfied
Capture the latest range image DG in response to DS input
repeat. When the end condition is satisfied, the three-dimensional camera 2
Sends a stop command to end the measurement process
(# 35). In addition, the user operates the display of the host 3.
A distance image DG is displayed on a 3b to monitor the measurement situation.
Can be Range image DG and two-dimensional color
It is also possible to display a captured image. According to the above embodiment, the photographing condition data
DS is used as a control signal for capturing the range image DG.
Therefore, there is no need to separately provide a capture control signal.
The user can select the measurement mode in continuous mode.
Period can be changed in frame units depending on the application.
You. According to the first aspect of the present invention, periodic measurement is performed.
The reliability of setting measurement conditions when performing
Can be.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a configuration diagram of a measurement system according to the present invention. FIG. 2 is a diagram illustrating an appearance of a three-dimensional camera. FIG. 3 is a block diagram illustrating a functional configuration of a three-dimensional camera. FIG. 4 is a principle diagram of calculation of a three-dimensional position in the measurement system. FIG. 5 is a block diagram of an output processing circuit and a memory. FIG. 6 is a diagram showing a reading range of a sensor. FIG. 7 is a block diagram of a center-of-gravity calculation circuit. FIG. 8 is a diagram showing a relationship between each point of the optical system and an object. FIG. 9 is a time chart showing the operation of the three-dimensional camera in the continuous mode. FIG. 10 is a time chart showing the operation of the three-dimensional camera in the continuous mode. FIG. 11 is a time chart showing the operation of the three-dimensional camera in the one-shot mode. FIG. 12 is a main flowchart of the operation of the system controller of the three-dimensional camera. FIG. 13 is a flowchart of a first scan sequence and a second scan sequence. FIG. 14 is a flowchart of the scanning process of FIG. 13; FIG. 15 is a flowchart of calculation of a projection angle. FIG. 16 is a flowchart of calculation of a slit light amount. FIG. 17 is a flowchart of a setting process of FIG. 14; FIG. 18 is a flowchart of a host measurement process. [Explanation of Signs] 2 Three-dimensional camera (three-dimensional measuring device) 40 Light projecting system (light projecting means) 53 Measurement sensor (imaging means) 61 System controller (control means) Q Object U Slit light (detection light)

────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Eiichi Ide 2-3-1 Azuchicho, Chuo-ku, Osaka-shi, Osaka Inside Osaka International Building Minolta Co., Ltd. (56) References JP-A-2-118538 (JP, A) JP-A-8-5344 (JP, A) JP-A-7-174536 (JP, A) JP-A 8-136225 (JP, A) JP-A-9-325509 (JP, A) JP-A-9 -325010 (JP, A) JP-A-9-325018 (JP, A) JP-A-9-325019 (JP, A) (58) Fields investigated (Int. Cl. ⁷ , DB name) G01B 11/00- 11/30 102 G01C 3/00-3/32 G02B 7/28-7/40 G03B 13/32-13/36 G06T 1/00-9/40

Claims (1)

(57) Claims 1. A light projecting means for irradiating a detection light to optically scan an object, and an imaging means for receiving the detection light reflected by the object. A three-dimensional measuring device for measuring an object shape by a light projection method, comprising: a distance measuring sensor for outputting a signal corresponding to the distance between the objects; and a measuring condition according to the distance between the objects measured by the light projection method. Control means for setting, as an operation mode of the control means,
After setting measurement conditions according to the distance between the objects measured by the light projection method, the output of the distance measuring sensor is monitored, and when the amount of change in the output exceeds an allowable value, the output of the distance measuring sensor is A three-dimensional measuring device provided with a mode in which a projection direction is determined based on the distance, a distance between objects is measured again by a light projection method, and a measurement condition is reset based on the result.