JPS59155705A - Inspecting equipment of interval of lattice object - Google Patents

Abstract

PURPOSE:To measure intervals and bends of rod-shape objects arranged in lattice form automatically and with high accuracy in an image measurement system using an ITV camera by providing an analog/digital conversion means, an initial threshold determination means, a comparator which binary-encodes the image information, an arithmetic means and a memory which stores interval values of the lattice object. CONSTITUTION:An output signal A (analog) from an ITV camera 1 is separated into a vertical synchronizing signal B and a horizontal synchronizing signal C by a synchronizing signal separation circuit 2. A horizontal synchronous counter 4 counts the horizontal synchronizing signal C and gives an A/D converter 5 an enable signal E when the scanning line is identical to the one directed by a scanning line disignation unit 16. When the enable signal E is on-state, a video signal D is converted into a digital signal F by the A/D converter 5 and taken into an image memory 6. A comparator 9 compares the data H of the memory 6 with the threshold I determined by an initial threshold determination circuit 8 and if H>I, a pulse M is transmitted to a white level counter 11.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a grid-like object spacing inspection device for measuring spacing, bending, etc. of fuel rods in a nuclear power plant using an industrial television system.

Typically, in nuclear power plants and the like, it is extremely important to measure the spacing and bending of fuel rods during use. Such measurements traditionally use industrial television (
Images of the fuel rods are reproduced on a television monitor using a camera (ITV), and the operator places a scale on the screen of the television monitor to perform visual inspection. For this reason, periodic inspection of the fuel rods requires a lot of time, which has the disadvantage of increasing the burden on the workers. Furthermore, when an ITV camera is used, there is a drawback that measurement errors are large due to changes in the illuminance of the object (fuel rod).

The present invention has been made in view of the above circumstances, and its purpose is to automatically and accurately measure the spacing and bending of rod-shaped objects arranged in a grid in an image measurement system using an ITV camera. An object of the present invention is to provide a grid-like object spacing inspection device that can be used to inspect the distance between objects.

An embodiment of the present invention will be described below with reference to the drawings. FIG. 1 is a block diagram showing the configuration of a grid-shaped object spacing inspection device according to the present invention.

Reference numeral 1 denotes an ITV camera that captures image information of a grid-like object to be measured, and transmits its output signal (analog signal) to a synchronization signal separation circuit 2 and a sample-and-hold circuit 3. The synchronization signal separation circuit 2 separates a horizontal synchronization signal C and a vertical synchronization signal B from the output signal A of the TV camera 1 and outputs the separated signals. The sample-and-hold circuit 3 samples and holds the analog signal A at an appropriate period to produce a discrete signal. 4 is a horizontal synchronization counter, and horizontal synchronization signal C
It has a function that allows it to count the video count of any scanning line. This horizontal synchronization counter 4 is reset by the vertical synchronization signal B. 5 is an analog-to-digital converter (A/D converter), which is enabled from the horizontal synchronization counter 4 +! It operates by an FE and converts the video signal (analog signal) D given from the sample/hold circuit 3 into a digital signal F and outputs it to the image memory 6.

This 1iin image memory 6 stores a digital signal) which is an image signal from the A, /I) converter 5. The comparator 9 is operated by a control signal K from the th control unit 7, compares the data (image signal F) H at each address in the image memory 6 and a preset threshold value, and performs an operation according to the magnitude relationship. Outputs a medium pulse (binarization coefficient). In this case (that is, when an image is binarized), the initial threshold value ■ is set by the initial threshold setting circuit 8. 1
0 is a black level counter, which counts the number of pulses output in the comparator 9 when the data H from the image memory 6 is smaller than the threshold value. In addition, 1 is a white level counter, and the comparator 9 uses the image memory 6 from the threshold value.
If the data H from 6 is thick, count the number of pulses output.

The black level pixel number register 12 stores the count value 0 of the black level counter 10 at a different address each time the output of the comparator 9 changes from the black level to the white level. Furthermore, when the output of the comparator 9 changes from the white level to the black level, the white level pixel number register 1 stores the current value of the white level counter 1 at a different address each time the output changes. Reference numeral 14 denotes a calculation unit which is operated by a control signal from the control unit 7, continuously outputs the data of the pixel number when the level changes from the pixel memory 15, calculates the width of the white level, and calculates the width of the white level set in advance. It performs a comparison operation with the width and outputs control signals J, , J, to the threshold value setting section in the comparator 9. The coordinate memory 15 stores the black level and white level pixel count registers 12 and 13.
Calculated from and store the pixel number when the novel changes. Reference numeral 16 denotes a scanning line specifying section which instructs the horizontal synchronization counter 4 to specify a scanning line in accordance with control from an external, for example, a host computer.

The operation of this basic configuration will be explained.

An output signal A (analog) from the ITV camera 1 is separated into a vertical synchronizing signal B and a horizontal synchronizing signal C after passing through a synchronizing signal separation circuit 2.

The horizontal synchronization counter 4 counts the lk auxiliary signal C, and when the scanning line specified by the scanning line specification section 16 is reached, the A/D
Issue enable=@w to converter 5. At this time, the vertical synchronization signal B acts as a reset signal for the counter 4. When the enable signal E is turned on, the video signal is converted into a digital signal F by the A/l) converter 5 and taken into the image memory 6. The above operations can be performed by manual switch operations or by commands from a host computer, and all processing after data has been added to the image memory 6 is performed based on the contents of the memory. Next, the comparator 9 uses the content H of the image memory 6 and the threshold value set by the initial threshold value setting circuit 8.
If H>I, the 4th pulse M is transmitted to the white level counter 1. Conversely, if H≦■, the nozzle L is sent to the black level counter 10. each counter 70
, 11 count this number and store the contents of the counter in registers 2 and 13, respectively, each time the level changes. At this time, reading memory 6, register 2.13
The control unit 7 controls the timing of writing to, etc. From the contents of register 2.13, the order when counting from the picture collection at the left end of the screen in #il when the black and white level changes (
The coordinates of the edges of the fuel rods are determined and stored in the coordinate memory 5. The calculation unit 14 reads data from the coordinate memory 5, calculates the width of the first white level counting from the left edge of the screen, compares it with the preset width of the fuel rod, and if it is outside the allowable range, sends a message to the comparator 9. Issue a command for threshold operation. If it is within the normal range, the next data in the coordinate memory 5 is accessed and the width of the white level is calculated. Similarly, a command is issued to the comparator 9 or procedures are taken to access the next data. Here, the casting part 14 is configured as shown in FIG. 2, for example. That is, the calculation unit 14 reads out the coordinate data S in accordance with the control signal R, and outputs the subtraction result T to the comparators 19 and 20. If the radius of the fuel rod is d, then the reference signal generator 18.2
From 1, d-Δd, respectively.

The signal d+Δd is used as a reference signal by comparators 19 and 20.
Served on. From the subtraction result T, the reference signal d−Δd,d+
If Δd is small, U and W are turned on, and if T is small, ■ and X are turned on. If the AND signal of jJl, l, U and W is turned on, the signal J2 is sent to the comparator 9 to increase the threshold value, and if the AND signal of V and X is turned on, the signal J1 is sent to the comparator 9 to make the threshold value smaller. Served. Also, if the AND of U and X is turned on, the scolding memory 15
A signal Y is sent to the control unit 7 to read the next data above. Comparator 9 receives signal J (Jl, J
! ), the data in the image memory 6 and the threshold are compared again. V lower, black and white level counting, loading into the monument memory 15, and threshold operation are repeated, but the rewriting of the coordinate memory 15 is performed by the cup number counter 22.
Replace only the data corresponding to . That is, when an instruction to capture an image is issued by manual operation or from a host computer, the trial counter 23 and the cup number counter 22
are both reset, and in this state, coordinate memory 1
5 are all rewritten, and the number of gold bars is recorded in the coordinate memory 15 according to the number of black and white level changes K.

Thereafter, the trial counter 23 is incremented each time the threshold value is operated, and if both the counters 22 and 23 are not zero, only the data corresponding to the cup number counter 22 is rewritten. When the number of gold bars recorded in the cup number counter 22 and the coordinate memory 15 match, the interval between the bars can be determined from the contents of the memory 15. Also, coordinate memory 1
5 stores the results of the above calculation for unbent fuel rods, and later stores the results for the fuel rods in use.
By comparing the results of the above calculations with a host computer, it is easy to see if the fuel rods are moving laterally, that is, if they are bent.

In this way, it is possible to measure the spacing and bending of fuel rods used in nuclear power plants and the like. In this case, as shown in FIG. 3, if the grid-shaped object spacing inspection device 32 of the present invention and the host computer 33 are connected online, the spacing and bending of the fuel rods 30 can be automatically measured. Therefore, the worker only needs to monitor the monitor TV 94 that displays the images sent from the TV camera 3, the inspection device 32 and the host computer 33.
Through this data processing, the spacing and bending of the fuel rods 30 can be confirmed very easily. Further, in the present invention, since the threshold value (threshold value of the comparator 9) is operated for each fuel rod 30, even if the illuminance differs somewhat from rod to rod, it can be prevented from affecting the measurement results. That is, as shown in FIG. 4, the video signal of the camera 31 (D in FIG. 1) is set to a predetermined voltage level! 1. ! 2. ! When an image is binarized in Step 3, by making the binarization threshold variable, the difference between the white level width P' and the bar diameter d can always be kept constant. Therefore, even if the illuminance varies from fuel rod to rod, measurement errors can be significantly reduced.

As described in detail above, according to the present invention, (1) In an image measurement system using a TV camera, it is possible to automatically and highly accurately measure the spacing and bending of rod-shaped objects arranged in a grid. Therefore, when inspecting fuel rods, etc. in a nuclear power plant, the burden on workers can be significantly reduced, and inspections can be performed with high precision.

[Brief explanation of drawings]

FIG. 1 is a block diagram showing the configuration of a grid-like object inspection device according to an embodiment of the present invention, FIG. 2 is a block diagram showing the specific configuration of the calculation section in FIG. 1, and FIG. 3 is the same as in FIG. 1. FIG. 4 is a block diagram showing the configuration of an online system for explaining the operation of FIG. 1, and FIG. 4 is a waveform diagram for explaining the operation of FIG. 1... ITV camera, 5... Analog-digital converter, 9... Comparator, 14... Arithmetic unit,
15...Coordinate memory.

Claims (1)

[Claims] In an image measurement system using an industrial television system, an analog-to-digital conversion means converts image information of a grid-like object to be measured into a digital signal, and a threshold value is used to convert the image information into a digital signal. an initial threshold setting means for setting an initial value; a converter for binarizing the box/image information based on a predetermined threshold including the initial threshold from the initial threshold setting means and the digital signal; Calculating means for calculating the ratio gN between the binary signal output from the gridter and the preset interval value of the grid-like object, and setting the threshold value based on the calculation result;
A grid-like object spacing inspection device comprising: a memory for storing spacing values of the grid-like objects based on a binary signal output from the comparator.