JPH09273923A - Data-processing apparatus and displacement sensor using the apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a displacement sensor which can measure a displacement of a surface to be measured with the use of a data-processing apparatus capable of moving an input signal waveform by the amount of a shift to a reference signal waveform. SOLUTION: An input signal waveform (actually measured waveform) representing a displacement pattern of a surface to be detected is induced by a control part 19 from measuring results of a measuring part 15 consisting of a light beam-scanning means 1, a photodetecting means 14, etc. The presence/absence of candidate points on the actually measured waveform which show approximately the same positional relationship as that of a plurality of characteristic points on a reference signal waveform set by a setting part 22 (reference waveform) is checked by a processing part 23. If there are candidate points, the actually measured waveform is moved until the candidate points come to the same position as the corresponding characteristic points. At this time, a ratio of an absolute value of a difference between a reference difference which is a difference of signal value of the characteristic points and a difference of signal value of the candidate points to the reference difference is calculated by the processing part 23, weighed in a predetermined manner and turned to scores. A minimum score is decided as the candidate point.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a data processing device for obtaining a deviation of an analog input signal waveform from a reference signal waveform and moving the input signal waveform by the deviation, and a data processing device using the data processing device. The present invention relates to a displacement meter that measures displacement.

[0002]

2. Description of the Related Art As a device for measuring the displacement of an object, there is an optical displacement measuring device to which a triangulation method is applied, which is composed of a combination of a light emitting element and a position detecting element (PSD). Is a light emitting diode or a semiconductor laser. In this optical displacement measuring device, the light from the light emitting element is condensed by the light projecting lens and applied to the object, and a part of the reflected light from the object is connected to the spot on the position detecting element by the light receiving lens. Since the position of the spot on the position detecting element moves each time the object moves, the amount of displacement to the object is measured by detecting the position of the spot.

[0003]

However, in the case of the conventional displacement measuring apparatus of this kind, since there is only one measuring point, the one-dimensional displacement of the object can be measured, but the two-dimensional displacement can be measured. It cannot be measured.

On the other hand, even in the case of an apparatus for measuring a two-dimensional displacement, when an object is conveyed on a line by a conveyor or the like, the object conveyed by the swell of the conveyor or the like may be moved in the vertical direction or Since the position of the object changes for each measurement due to the position change in the left-right direction, if the position of the object changes for each measurement in this way, for example, the property such as unevenness of the object surface may be as predetermined. There is a problem in that it is not possible to make an accurate and stable determination when making a determination as to whether or not an abnormality such as adhesion of foreign matter on the surface of an object is made.

A problem to be solved by the present invention is to provide a data processing device capable of moving an input signal waveform by a shift amount with respect to a reference signal waveform, and a device for accurately and stably displacing an object surface using the data processing device. It is to provide a displacement meter that can measure.

[0006]

According to the first aspect of the present invention,
An input waveform storage unit that stores a waveform of an input signal, a reference waveform storage unit that stores in advance a reference signal waveform that serves as a comparison reference of the input signal waveform, and a plurality of waveforms that characteristically change on the reference signal waveform. The presence / absence of a candidate point on the input signal waveform that has substantially the same positional relationship as the positional relationship between the setting unit for setting and operating the individual characteristic points and each of the characteristic points set by the setting unit is checked. When there are these candidate points, the processing unit moves the input signal waveform to the same position as the characteristic point corresponding to the candidate point.

At this time, the processing unit has a function of comparing and determining the input signal waveform after the movement with the reference signal waveform as described in claim 2, or as described in claim 3, It is preferable to have means for displaying or outputting the fact when there is no candidate point.

Further, according to a fourth aspect of the present invention, the processing unit causes the reference value of the difference value between the reference difference, which is the difference between the signal values of the feature points, and the difference between the signal values of the candidate points, respectively. It is effective to have a function of calculating a ratio with respect to the difference, weighting the calculated ratio by a predetermined weight to make a score, and making a candidate having a minimum integrated value of the scores.

In addition, as described in claim 5, the processing unit displays a warning when there are a plurality of the candidate points derived for each of the feature points set by the operation of the setting unit, or It is preferable to have an output means.

By the way, a sixth aspect of the present invention is a displacement meter using the data processing device according to the first, third, fourth or fifth aspect, which is for converting a physical change amount of an object into an electric signal. Section, an input signal waveform deriving section for deriving an input signal waveform based on the electric signal, a light beam scanning means for scanning a light beam in a predetermined scanning plane, and a light beam by the light beam scanning means for subject surface. And a measuring unit including a light receiving unit that receives reflected light from the object when the light is projected onto the object and outputs a light receiving signal, and represents a displacement pattern of each light projecting point on the surface of the object based on the light receiving signal. An input signal waveform deriving unit for deriving an input signal waveform, and determining whether or not there is a deviation portion in the input signal waveform after being moved by the processing unit that exceeds an allowable range with respect to the reference signal waveform. The pair It is characterized in that it comprises a quality determination unit for performing quality determination of the object.

According to such a displacement meter, the object is always conveyed by, for example, a conveyor, and even if the position of the object changes for each measurement such as vertical and horizontal changes due to the swell of the conveyor, the reference is always maintained. The input signal waveform after moving at the same position as the signal waveform can be compared with the reference signal waveform, and whether the input signal waveform is abnormal or not is judged regardless of the fluctuation of the object due to the swell of the conveyor etc. It becomes possible to make a judgment.

[0012]

DESCRIPTION OF THE PREFERRED EMBODIMENTS One embodiment of the present invention will be described.
This will be described with reference to FIGS. 1 to 7. First, FIG. 1 shows a schematic configuration of a displacement meter. In FIG. 1, reference numeral 1 is a light beam scanning means for scanning a light beam within a predetermined scanning plane, for example, a laser diode driven by a driver 2 or the like. A light beam generator 3 for generating a light beam, which comprises a combination of the light emitting element and the collimator lens of
It is composed of a scanning control unit 4 including a motor and its control circuit, and a reflecting mirror 5 that is driven by the scanning control unit 4 and deflects the light beam from the light beam generator 3. An object (hereinafter referred to as a work) 8 that is scanned in a horizontal plane) and has a groove 7 on the surface and is conveyed by a conveyor such as a conveyor (not shown) is irradiated with light so that the scanning direction is substantially orthogonal to the direction of the groove 7. The beam is projected.

Further, 11 is a condenser lens for condensing the light beam reflected by the work 8, and 12 is a condenser lens 11.
A position detection element (hereinafter referred to as PSD) that outputs a light reception signal according to the spot position of the reflected light condensed by
Is an amplifying section for amplifying the output signal of the PSD 12, and the light receiving means 14 is constituted by the condensing lens 11, the PSD 12 and the amplifying section 13. The light receiving means 14 and the light beam scanning means 1 are provided on the surface of the work 8. A measurement unit 15 is configured as a conversion unit that measures a displacement that is a physical change amount at each light projection point.

Reference numeral 17 is an A / D converter for analog / digital converting the signal amplified by the amplifier 13.
Is a control signal generator that generates a control signal for the motor of the scan controller 4 and adjusts its span and shift amount.
Reference numeral 9 denotes a control unit composed of a logic array, a microcomputer, etc., which has a function of controlling the driver 2 and the control signal generation unit 18, and is displaced by unevenness of each projection point on the work 8 from the measurement result by the measurement unit 15. A measured waveform storage section that is an input waveform storage section that has a function as an input signal waveform deriving section that derives an analog input signal waveform that represents a pattern (hereinafter referred to as an actually measured waveform), and stores the derived actually measured waveform; A built-in reference waveform storage unit that stores in advance a reference signal waveform (hereinafter referred to as a reference waveform) that serves as a comparison reference of the actually measured waveform. The actual measurement storage unit and the reference storage unit do not necessarily have to be built in the control unit 19, and may be external ones.

At this time, the reference waveform to be stored in the reference waveform storage unit is such that the light beam from the light beam scanning means 1 is projected onto the reference work so that the scanning direction is orthogonal to the groove, and the reference work surface is covered. It may be either one obtained by measuring the displacement pattern of each light projecting point or one created by inputting waveform data by an input means such as a keyboard.

Further, in FIG. 1, reference numeral 21 is a display unit composed of an LCD or the like for displaying a reference waveform and an actually measured waveform on a display screen, and 22 is three characteristics in which irregularities which are characteristics thereof are characteristically changed on the reference waveform. Setting section for setting and operating points, 2
Reference numeral 3 denotes a processing unit, which examines the presence or absence of three candidate points on the measured waveform that have a positional relationship that is substantially the same as the positional relationship in the XY coordinate system between the respective feature points set by the setting unit 22, and checks these candidates. When there is a point, it has a function to move the measured waveform until one of the candidate points is at the same position as the corresponding characteristic point, and after the movement, compares the measured waveform with the reference waveform and The work 8 is judged by judging whether there is a deviation portion that exceeds the allowable range with respect to the reference waveform.
It has a function as a pass / fail determination unit for performing pass / fail determination.

By the way, the processing unit 23 calculates the ratio of the difference value between the reference difference, which is the difference between the signal values of the feature points, and the measured difference, which is the difference between the signal values of the candidate points, to the reference difference, Predetermined weighting is applied to the calculated ratio to make points, and whether or not each candidate point is determined by whether or not this score is smaller than a predetermined value. As an example of scoring by this weighting, for example, the above ratio is 2
0% or less 0 point, 4% or less 1 point, 6% or less 2
Non-linear weighting such as 4 points if less than 8%, 8 points if less than 10%, 20 points if less than 14%, 40 points if less than 20%, 100 points if more than 20% is considered. Not limited to this, weighting may be appropriately performed according to the characteristics of the measuring unit 15, and linear weighting may be performed in addition to non-linear weighting.

Next, the operation of detecting the candidate points on the actually measured waveform by the processing unit 23 will be described with reference to the flowchart of FIG.
This will be described with reference to the operation explanatory diagram of FIG.

Now, either one or both of the reference waveform K (see FIG. 3) and the actually measured waveform J (see FIG. 4) are selectively displayed on the display section 21, and work is performed based on the display screen of the reference waveform K. An operator operates the setting unit 22 to generate three characteristic points P1, whose characteristic waveform changes on the reference waveform K1.
When P2 and P3 are set, the time axis is the X axis and the signal value is Y.
As the axes, the coordinates of these characteristic points P1, P2, P3 are (X1, Y1), (X2, Y2), (X3, Y3), respectively, and the positional relationship between the characteristic points P2, P1 is shown in FIG. Is the difference between X and Y coordinate values ΔX (= X2-X1), ΔY (= Y2-Y
1) is calculated (step S1). This ΔY is
For example, it corresponds to a reference difference which is a difference in the signal value of the reference waveform K due to the step of the groove of the reference work.

Then, on the measured waveform J, both feature points P1 and P
Candidate points PA and PB having the same positional relationship as the positional relationship between the two
2, the X coordinate value XA of a certain point PA ′ on the measured waveform J is set to n and the point PA ′ is detected.
, The point PB 'at which the X coordinate value XB becomes (XA + ΔX) is derived (step S2), and the Y coordinate values YB and YA of the derived points PB' and PA 'are derived (step S3). ), Reference difference ΔY and Y of both points PA and PB
Difference value (= d1−) from the measured difference d1 (= YB−YA) of the coordinate values.
An absolute value d2 of ΔY) is calculated (step S4). Here, the reference difference ΔY is replaced with d3 in step S4.

Thereafter, the upper limit value and the lower limit value of the reference difference d3 (= ΔY) are set to 5 mm and 1 mm, respectively, and the reference difference d
It is first judged whether or not 3 exceeds the upper limit value (step S5). If the judgment result is YES, the reference difference d
3 is replaced by the upper limit value of 5 mm (step S6),
If the determination result is NO, after the process of step S6, the process proceeds to step S7, and it is determined whether the reference difference d3 is smaller than the lower limit value of 1 mm (step S7).
7) If the determination result is YES, the reference difference d3 is replaced with the lower limit value of 1 mm (step S8), and if the determination result is NO, after the processes of steps S6 and S8, the next step S9 is performed. Move to.

The difference value calculated in step S4
The ratio of the absolute value d2 of (= d1−ΔY) to the reference difference d3 (= ΔY) is calculated, and the calculated ratio is given a predetermined weight to be scored (step S9). The same process as the scoring process from S1 to S9 is performed between the characteristic points P1 and P3 (step S10), and is also performed between the characteristic points P2 and P3 (step S11). It is determined whether or not the total of the respective scores obtained is smaller than the current optimal score (step S12), and the determination result is NO.
If so, it is determined that the points set on the measured waveform J cannot be candidate points for the characteristic points P1, P2, and P3 on the reference waveform K, the operation ends, and the determination result is YES. For example, it is determined that each point set on the actual measurement waveform J can be a candidate point for each of the characteristic points P1, P2, P3 on the reference waveform K. In this example, 1000 points of data are discretely captured as waveform data. Therefore, as will be described later, among the points that can be candidate points when the X coordinate value XA (= n) of the point PA ′ is sequentially changed from 0 to 999, the optimum point with the smallest total score is selected. The position and its score are updated and held (step S13), after which the candidate point detection processing operation ends.

Next, the matching processing operation of the measured waveform J with the reference waveform K will be described with reference to the flowchart of FIG. 5 and the operation explanatory diagrams of FIGS.

Now, a point P on the measured waveform J (see FIG. 6)
It is assumed that candidate point detection for each feature point is performed by sequentially changing the X coordinate value XA (= n) of A ′ from 0 to 999, for which purpose, as shown in FIG. The X coordinate value XA (= n) of'is set to 0 (step T1), the candidate point detection process shown in FIG. 2 is performed (step T2), and it is determined whether n = 999 (step T3). If the determination result is NO, n is replaced with (n + 1) and incremented (step T4), and then the process returns to step T2, and from the process of steps T2 to T4, n = 0 on the measured waveform J Candidate point detection processing is performed for each of the points up to 999, and the optimum points that can be candidate points are derived. Note that n
Is not limited to 999.

Then, the determination result of step T3 is YES.
If so, the process proceeds to the next step T5, and the optimum points obtained by such candidate point detection processing are evaluated, that is, the total number of these optimum points by the above weighting is 100.
It is determined whether or not it is less than or equal to the point (step T5), and if the determination result is NO, it is determined that the optimum point is not a candidate point and the measured waveform J does not match the reference waveform K, and all measurement conditions and data are determined. It is invalidated, and then the matching processing operation ends.

On the other hand, if the decision result in the step T5 is YES, it is decided that the optimum point is a candidate point and the actually measured waveform J can match the reference waveform K. For example, as shown in FIG. Point P1 and corresponding measured waveform J
Difference in X coordinate value with the above candidate point PA δX (= XA−X
The measured waveform is moved in the X-axis direction by the amount of 1) (step T6), and the Y coordinate value between the characteristic point P1 on the reference waveform K and the corresponding candidate point PA on the measured waveform J is changed. The measured waveform J is moved in the Y-axis direction by the amount of the difference δY (= YA−Y1), and the measured waveform J is moved to a position matching the reference waveform K as shown in FIG. 7 (step T
7) After that, the matching processing operation of the measured waveform J with respect to the reference waveform K ends.

Further, for example, when foreign matter is attached in the groove 7 of the work 8, the reference waveform K is included in the measured waveform J.
However, since there is a deviation that exceeds the allowable range with respect to the reference waveform K, whether there is a deviation that exceeds the allowable range with respect to the reference waveform K in the actually measured waveform J after the movement (see FIG. 7). The determination is made by the processing unit 23, and the work 8
The pass / fail judgment is made. Although the falling edge at the right end of the waveform in FIG. 7 indicates that there is no data in the measured waveform J before the movement, even if there is no data in the calculation as described above, just before that. You may make it perform the process which hold | maintains data.

Therefore, even when the work 8 fluctuates vertically and horizontally due to, for example, undulations of the transfer conveyor,
Since the actually measured waveform J can be moved and corrected to a position overlapping the reference waveform K, the actually measured waveform J after the movement can always be compared with the reference waveform K at the same position as the reference waveform K, regardless of the variation of the work 8. It is possible to accurately and stably measure the presence or absence of abnormalities such as adhesion to the surface of the work 8 as well as the quality of the unevenness of the surface of the work 8.

Further, as described above, the processing unit 23 causes, for example, the Y coordinate values (signal values) of the feature points P1 and P2, respectively.
Difference ΔY (= Y2-Y1) which is the difference between the candidate points PA and P
Actual measurement difference d1 that is the difference between the Y coordinate values (signal values) of B
The ratio of the absolute value d2 of the difference value (d1-ΔY) with (= YA-YB) to the difference of the reference difference ΔY (= d3) is calculated, and the calculated ratio is given a predetermined weight to make a score. Depending on whether or not is smaller than a predetermined value, the candidate points PA, PB
Since it is determined whether or not there is a candidate point according to the characteristics of the measurement unit 15 and various measurement conditions.

Further, when setting three characteristic points on the reference waveform K, the third point P3 may be anywhere on the waveform as long as it is on the right side of the position shown in FIG. 3, and the setting of the third point P3. By this, the range to be searched is limited, and the speed of the candidate point detection processing can be increased, and at the same time, it is possible to protect when the measured waveform J is extremely shifted during the matching processing.

By the way, in the above-described embodiment, when the processing unit 23 has a plurality of candidate points obtained according to the procedure of the flow chart of FIG. 2 for each feature point set by the operation of the setting unit 22, In order to inform that the point cannot be set uniquely, it may have a function to drive warning warning means such as a buzzer or a lamp to give some warning. When an unskilled worker performs feature point setting work,
For example, when an attempt is made to set the third feature point, a warning is given and it is easily understood that the setting of the previous feature point is not appropriate, and it is possible to always easily set the optimum feature point.

Although the above embodiment has described the displacement meter having the function of performing the matching process of the actually measured waveform J with respect to the reference waveform K, the present invention is not limited to such a displacement meter. The data processing apparatus may have only the function of finding the deviation of the input signal waveform with respect to the reference signal waveform and moving the input signal waveform to match with the reference signal waveform. Further, such a data processing apparatus is used. It goes without saying that equipment other than the displacement gauge may be used.

Further, it goes without saying that the processing section 23 may be provided with means for displaying or outputting the fact when there is no candidate point.

In the above embodiment, the case where the number of characteristic points set in the reference waveform K is three has been described, but from the principle of matching the actually measured waveform J with the reference waveform K, only two characteristic points are required. On the other hand, it is a matter of course that four or more feature points may be set, and in this case, the candidate point is the one having the smallest integrated value of the points by weighting when the candidate point is detected. It is possible to further improve the matching accuracy of the actually measured waveform by setting the characteristic points equal to or more than the points.

Further, in the above-described embodiment, the work 8 has the groove 7.
Although the present invention has been described above, the present invention can be implemented in the same manner even if the groove is provided with a protrusion.

[0036]

As described above, according to the invention described in claim 1, since the input signal waveform can be moved to the same position as the reference signal waveform, after the movement as described in claim 2, It becomes possible to always compare the input signal waveform at the same position as the reference signal waveform when the input signal waveform is compared and judged with the reference signal waveform.

At this time, when the processing section is provided with a means for displaying or outputting the fact that there is no candidate point, the input signal waveform may not match the reference signal waveform. Easy to understand.

Further, as described in claim 4, by scoring by weighting, it becomes possible to judge the presence or absence of the candidate points according to the characteristics of the measuring unit and various measuring conditions.

Further, according to a fifth aspect, the processing unit issues a warning when there are a plurality of the candidate points derived for each of the feature points set by the operation of the setting unit, or a display unit or an output unit. With this feature, even an inexperienced worker can always easily set optimum feature points.

By the way, according to the displacement gauge of the sixth aspect, even when the position of the object changes every measurement,
You can always compare the input signal waveform after moving at the same position as the reference waveform with the reference signal waveform, and accurately check whether the unevenness of the surface of the object is good or not, and whether there is any abnormality such as adhesion of foreign matter to the surface of the object. It is possible to measure in a stable and stable manner.

[Brief description of drawings]

FIG. 1 is a block diagram of an embodiment of the present invention.

FIG. 2 is a flowchart for explaining the operation of the above.

FIG. 3 is an operation explanatory diagram of the above.

FIG. 4 is an operation explanatory view of the above.

FIG. 5 is a flowchart for explaining the same operation as above.

FIG. 6 is an operation explanatory view of the above.

FIG. 7 is an operation explanatory diagram of the above.

[Explanation of symbols]

 1 Light Beam Scanning Means 7 Grooves 8 Workpiece (Target) 14 Light Receiving Means 15 Measuring Section 19 Control Section 22 Setting Section 23 Processing Section K Reference Waveform (Reference Signal Waveform) J Measured Waveform (Input Signal Waveform) P1, P2, P3 Features Points PA, PB Candidate points

Claims (6)

[Claims] 1. An input waveform storage unit that stores a waveform of an input signal, a reference waveform storage unit that stores in advance a reference signal waveform that serves as a comparison reference of the input signal waveform, and the waveform is characterized on the reference signal waveform. A setting unit for setting and operating a plurality of characteristic points that change dynamically, and candidates on the input signal waveform that have substantially the same positional relationship as the positional relationship between each of the characteristic points set by the setting unit. A data processing apparatus, comprising: a processing unit that examines the presence or absence of a point and moves the input signal waveform to the same position as the characteristic point corresponding to the candidate point when the candidate point exists. 2. The data processing apparatus according to claim 1, wherein the processing section has a function of comparing and determining the input signal waveform after the movement with the reference signal waveform. 3. The data processing apparatus according to claim 1, wherein the processing section includes means for displaying or outputting when the candidate point does not exist. 4. The processing unit calculates a ratio of a difference value between a reference difference, which is a difference between signal values of the feature points, and a difference between signal values of the candidate points, to the reference difference,
4. The data processing apparatus according to claim 1, further comprising a function of assigning a predetermined weight to the calculated ratio to make a score, and making a candidate having a minimum integrated value of scores as a candidate point. . 5. The processing unit includes a display unit or an output unit that issues a warning when there are a plurality of candidate points derived for each feature point set by the operation of the setting unit. The data processing device according to claim 1, wherein the data processing device is a data processing device. 6. A conversion unit for converting a physical change amount of an object into an electric signal, an input signal waveform deriving unit for deriving an input signal waveform based on the electric signal, and the input after being moved by the processing unit. 7. A quality determination unit for determining whether the target object is good or bad by determining whether or not the signal waveform has a shift portion that exceeds an allowable range with respect to the reference signal waveform. A displacement meter using the data processing device according to 1, 3, 4 or 5.