JP3585467B2 - Method and apparatus for measuring position and swing amount of ultrasonic probe - Google Patents

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a method and an apparatus for measuring a position and a swing amount of an ultrasonic probe.
[0002]
[Prior art]
In ultrasonic testing, in order to analyze the test results, identify the position of the reflection source, and image the test results, the position data of the ultrasonic probe (the amount of movement from the reference point) is required. . Further, the swinging scanning of the probe is mainly used in manual flaw detection, but it is difficult to quantitatively detect the swinging amount by the conventional flaw detection method.
[0003]
[Problems to be solved by the invention]
One of the methods for detecting the position of the ultrasonic probe is a method of directly measuring using a scale (a ruler) or the like. This is a method mainly used in a manual flaw detection test, and has problems in efficiency, accuracy, reproducibility and the like of the test. In addition, the detection method using a sensor includes a detection method in which the probe and the detection sensor are integrated, and a detection method in which the probe is separated from the sensor (that is, using an external sensor).
[0004]
In the former integrated detection method, there is a method of (1) incorporating a probe into a device similar to a computer mouse, a ball in the mouse comes into contact with a test object, and the ball is rotated when the probe moves. . The amount of rotation of the sphere is detected by two encoders in contact with the sphere, and the amount of movement in the vertical and horizontal directions is detected. The integrated detection method further includes (2) a method in which a barcode is attached to the surface of a test sample and the amount of movement is detected by a barcode sensor.
[0005]
However, in the method of (1) in this integrated detection method, if there is a couplant, the couplant enters the contact portion between the test sample and the mouse sphere or the contact portion between the mouse sphere and the encoder, The friction coefficient decreases, the ball slips, and the amount of movement cannot be detected. In the method (2), if a bar code is present on the surface of the test body, the surface state changes, which affects the flaw detection test result. In addition, since it is necessary to attach a barcode to the surface of the test specimen, the method cannot be applied to any place other than the place where the barcode is attached. Due to the characteristics of barcodes, only one-dimensional movement can be measured. Neither of the methods (1) and (2) can detect the swing amount of the probe.
[0006]
On the other hand, the latter separation type (using an external sensor) detection method includes the following five methods. (1) A method in which the probe is controlled and scanned from outside, and a sensor for detecting the amount of movement is also provided outside (mainly automatic flaw detection). The amount of movement of the probe is measured indirectly.
(2) A method of measuring the position of the probe with a scale (manual rule) (manual flaw detection).
(3) A method in which a mark such as an LED is attached to the probe, the position of the probe is calculated by a plurality of externally arranged cameras based on the principle of triangulation, and the amount of movement is detected.
(4) A method of measuring the position of the probe using sound waves according to the same principle as (3).
(5) A method of detecting the movement amount of a probe using two wire encoders (Japanese Patent Application Laid-Open No. 9-274024).
[0007]
In any of these methods, since the mouse and the ultrasonic probe are not integrated, the structure becomes complicated and direct measurement cannot be performed.
Accordingly, an object of the present invention is to provide a method and an apparatus for measuring the relative position (or the amount of movement) of a probe and the amount of swing of the probe without contacting a test object.
[0008]
[Means for Solving the Problems]
The method for measuring the position and swing amount of an ultrasonic probe according to the present invention includes providing at least one pair of optical non-contact in-plane displacement sensors at predetermined intervals on the ultrasonic probe, Determining the movement reference position of the probe above, recording the movement position of each sensor in XY rectangular coordinates, and calculating the position and swing amount of the probe as a function of the coordinate position of each sensor. Calculation.
[0009]
The function of the coordinate position of each sensor is determined by the following equation.
X direction position = δXa-m · sin θ
Y direction position = δYa + m · cos θ
Swing amount θ = sin ⁻¹ {(δXa−δXb) / L}
Where L is the distance between a pair of sensors,
m is the distance from one sensor to the point of incidence on the specimen surface,
δXa is the moving distance of one sensor in the X direction,
δXb is the moving distance of the other sensor in the X direction,
δYa is the movement distance of one sensor in the Y direction.
[0010]
An apparatus for measuring the position and swing amount of an ultrasonic probe according to the present invention includes an ultrasonic probe and at least one pair of optical non-contact in-plane displacements attached to the probe at a predetermined interval. The sensor includes a sensor, a start switch for determining a movement reference position of the probe on the surface of the test piece, an output terminal for outputting a position signal, and an output terminal for outputting a flaw detection signal.
[0011]
The sensors are preferably mounted on the front and rear sides or the left and right sides of the ultrasonic probe. Further, the sensors may be attached to one of the front and rear sides and one of the left and right sides of the ultrasonic probe, and the sensors may be attached to the front and rear sides and the left and right sides of the ultrasonic probe, respectively. Alternatively, one pair of sensors may be attached to the front and rear sides of the ultrasonic probe and two pairs of sensors may be attached to the left and right sides.
[0012]
BEST MODE FOR CARRYING OUT THE INVENTION
With reference to FIGS. 1-6, a description will be given of an embodiment of a method and an apparatus for measuring the position and swing amount of an ultrasonic probe according to the present invention.
[0013]
As shown in FIGS. 1-4, the measuring device for measuring the position and swing amount of the ultrasonic probe according to the present invention includes:
An ultrasonic probe 1, at least one pair of optical non-contact in-plane displacement sensors 2 a and 2 b attached to the probe 1 at a predetermined interval, and a probe on the surface of the test piece 3 A start switch 4 for determining a movement reference position, an output terminal 5 for outputting a position signal, and an output terminal 6 for outputting a flaw detection signal. Here, the in-plane displacement refers to a displacement along a plane or a curved surface.
[0014]
As shown in FIG. 1, the output terminal 5 is connected to a computer 7, and the output terminal 6 is connected to an ultrasonic flaw detector 8. The computer 7 is connected to the ultrasonic flaw detector 8 and exchanges signals with each other. A vibrator 11 is provided inside the ultrasonic flaw detector 1.
[0015]
When performing an ultrasonic test, a specific position is designated as a reference position by a switch 4 attached to the ultrasonic probe 1, and a signal of the switch 4 is output to a computer 7 through an output terminal 5. At this time, the outputs of the sensors 2a and 2b are returned to the initial values. The displacement output from the sensors 2a and 2b indicates the amount of movement of the sensor, and is output to the computer 7 as an electric signal through the output terminal 5. The sensors 2a and 2b are fixed to peripheral side surfaces excluding the upper and lower surfaces of the ultrasonic probe 1. In the example shown in FIG. 1, the sensors 2a and 2b are fixed to the front and rear side surfaces of the ultrasonic probe 1, and are disposed apart from each other by a predetermined distance L.
[0016]
FIG. 4 is a plan view showing various modified examples of the ultrasonic probe 1 based on the present invention. The sensors 2a and 2b are fixed to the front and rear surfaces of the ultrasonic probe 1 ((A) in FIG. 4), fixed to the left and right side surfaces ((B) or (D) in FIG. 4), and Whether it is fixed to one of the side surfaces and one of the left and right side surfaces ((C) or (E) of FIG. 4), or is fixed to each of the front and rear side surfaces and the left and right side surfaces in pairs (FIG. ) Or (G)), one pair on the front and rear sides and two pairs on the left and right sides, respectively (FIG. 4H).
[0017]
In the method for measuring the position and the amount of swing of the ultrasonic probe according to the present invention, at least a pair of optical non-contact in-plane displacement sensors 2a and 2b are provided on the ultrasonic probe 1 at a predetermined interval L. Determining the movement reference position of the probe 1 on the surface of the test body 3, recording the movement position of each sensor 2a, 2b in XY rectangular coordinates, and searching as a function of the coordinate position of each sensor 2a, 2b. It consists of calculating the position of the tentacle 1 and the amount of swing.
[0018]
The computer 7 receives the electric signal output from the sensors 2a and 2b via the output terminal 5, and calculates the position and the swing amount of the ultrasonic probe 1 as follows based on the method of the present invention. I do.
[0019]
With reference to FIGS. 4 and 5, a method of measuring the position and the swing amount of the ultrasonic probe 1 according to the present invention will be described. In the following calculation, as an example, the sensors 2a and 2b are attached to the front and rear side surfaces of the probe 1, the distance between the sensors 2a and 2b is L, and the distance from the sensor 2a to the incident point on the surface of the specimen 3 is m. I do. The swing angle is positive in the clockwise direction. Note that the same principle can be used to calculate the case where the arrangement of the sensors changes.
[0020]
A specific position (e.g., a measurement start point, a start start point, etc.) is determined as a reference position, and the X and Y components of the amount by which the sensors 2a and 2b have moved from the reference position are δXa and δYa for the sensor 2a. 2b is δXb and δYb.
[0021]
When the probe 1 does not perform swiveling scanning, δXa = δXb and δYa = δYb. The amount of movement of the probe 1 at that time is δXa and δYa for each component.
[0022]
On the other hand, when the probe 1 performs head swing scanning (head swing angle θ), δXa ≠ δXb or δYa ≠ δYb. The swing amount θ is sin ⁻¹ {(δXa−δXb) / L} or cos ⁻¹ [{L− (δYa−δYb)} / L] . When the head 1 is swung, the moving amount of the probe 1 is δXa−m · sin θ for the X component and δYa + m · cos θ for the Y component.
[0023]
FIG. 5 shows a flowchart of the measurement of the position of the probe and the amount of swinging, summarizing the above results.
In the present invention, the sensor mounting position may be variously modified as shown in FIG. 4, but in any of the examples, the above-described calculation formula can be basically applied.
[0024]
INDUSTRIAL APPLICABILITY The present invention can be applied to an ultrasonic inspection test for a metal material, a welded portion of a metal, and an ultrasonic inspection test for a ceramic, a composite material, and the like.
[0025]
【The invention's effect】
According to the present invention, the following effects can be obtained.
(1) In the ultrasonic flaw detection test, the swing amount can be quantitatively measured, and a tilted defect can be detected and quantitatively evaluated.
(2) In manual flaw detection, the position of the probe, which was previously measured using a scale, can now be measured without using a scale, improving the efficiency of flaw detection work, improving accuracy, reliability, and reproducibility. it can.
(3) In manual flaw detection, the feasibility of recording flaw detection results is improved, and the flaw detection results can be imaged even in areas where automatic UT is difficult, so that the feasibility of recording flaw detection results, reproducibility, and reliability are improved.
(4) Even in a portion having a curved surface or a three-dimensional shape, the movement amount of the probe can be directly measured along the surface shape, and the recordability and reproducibility of the flaw detection result can be improved.
(5) By using a non-contact optical sensor, the amount of movement of the probe can be measured even if the couplant is attached to the surface of the test piece, and the recordability and reproducibility of the flaw detection result can be improved.
(6) A process such as attaching a bar-code-like pattern to the surface of the test body becomes unnecessary, and the reliability, recordability, and reproducibility of the flaw detection result can be improved.
[Brief description of the drawings]
FIG. 1 is a front view of an ultrasonic probe according to the present invention.
FIG. 2 is a perspective view of the ultrasonic probe shown in FIG. 1 as viewed from one end face side.
FIG. 3 is a perspective view of the ultrasonic probe shown in FIG. 1 as viewed from a bottom surface side.
FIG. 4 is a plan view showing various modifications of the ultrasonic probe according to the present invention.
FIG. 5 is an explanatory diagram showing the principle of measuring the moving amount and the swing amount of the ultrasonic probe according to the present invention.
FIG. 6 is a flowchart showing a procedure for calculating the amount of movement and the amount of swing of the ultrasonic probe according to the present invention.
[Explanation of symbols]
1: Ultrasonic probe, 2a, 2b: Sensor, 3 specimens, 4 Start switch,
5: output terminal, 6 output terminal, 7: computer, 8: ultrasonic flaw detector.

Claims (8)

Providing at least one pair of optical non-contact in-plane displacement sensors at predetermined intervals on the ultrasonic probe; determining a movement reference position of the probe on the surface of a test object; moving each of the sensors Measuring the position and swing amount of the ultrasonic probe, comprising recording the position in XY rectangular coordinates, and calculating the position and swing amount of the probe as a function of the coordinate position of each sensor. Method. The measuring method according to claim 1, wherein the function of the coordinate position of each sensor is determined by the following equation.
X direction position = δXa-m · sin θ
Y direction position = δYa + m · cos θ
Swing amount θ = sin ⁻¹ {(δXa−δXb) / L}
Where L is the distance between a pair of sensors,
m is the distance from one sensor to the point of incidence on the specimen surface,
δXa is the moving distance of one sensor in the X direction,
δXb is the moving distance of the other sensor in the X direction,
δYa is the movement distance of one sensor in the Y direction. An ultrasonic probe, at least one pair of optical non-contact in-plane displacement sensors attached to the probe at a predetermined interval, and defining a movement reference position of the probe on the surface of the test object An apparatus for measuring the position and swing amount of an ultrasonic probe, comprising a start switch, an output terminal for outputting a position signal, and an output terminal for outputting a flaw detection signal. The measuring device according to claim 3, wherein the sensor is attached to front and rear side surfaces of the ultrasonic probe. The measuring device according to claim 3, wherein the sensors are attached to left and right side surfaces of the ultrasonic probe. The measuring device according to claim 3, wherein the sensor is attached to one of front and rear side surfaces and one of left and right side surfaces of the ultrasonic probe. The measuring device according to claim 3, wherein a pair of the sensors is attached to each of front and rear side surfaces and left and right side surfaces of the ultrasonic probe. The measuring device according to claim 3, wherein one pair of the sensors is attached to front and rear sides of the ultrasonic probe and two pairs of sensors are attached to left and right sides of the ultrasonic probe.

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