JPS60131415A - Detecting method of shape of object to be measured - Google Patents

Abstract

PURPOSE:To improve precision by comparing the coefficient of an approximate curve near the minimum value of the level of a reflected signal from a body to be measured with the coefficient of the approximate curve of every objective body which is stored previously in a storage device. CONSTITUTION:The minimum value of the level of the reflected signal obtained by making a parallel scan through the center position of a detection hole while slanting the wave transmission and reception surface of an ultrasonic wave transducer 73 at a specific angle to the objective body 81 in the scanning direction is detected. The coefficient (a) of a secondary curve obtained by carrying out interpolation using secondary recurrence as to the circumference of the minimum value. While the ultrasonic wave transducer 73 sends the ultrasonic wave of specific frequency to the body 81 to be measured, the reflected signal from the objective body 81 is stored in a memory 76 and its level P1 is detected. Then, the center position of a hole 82 to be detected is detected on the basis of the level of the reflected signal from the objective body 81 including the objective hole 82.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to a method for detecting the shape of an object to be measured using ultrasonic waves.

Configuration of conventional example and its problems Conventional methods for detecting the shape of an object to be measured include the position and orientation of the object from the reflected signal intensity obtained by rotating and scanning an ultrasonic transceiver element with respect to the object to be measured. There is something that detects

The outline of the contents will be explained below.

FIG. 1 is a system diagram showing the general configuration of a conventional device. Figure 2 is a perspective view showing position detection using a conventional device. In Figure 1, when the high voltage pulse 17 shown in Figure 3 is applied to the ultrasonic transmitting and receiving element 1, a predetermined An ultrasonic pulse with a certain frequency is emitted.◎This ultrasonic pulse is reflected by the target object 13 in FIG. After being amplified by the received signal amplifier 3, it is analog-to-digital converted and stored in the memory 5. Figure 3 shows the operating waveform of the ultrasonic transceiver element 1 stored in the memory 6. 3.7. 38 and 39 indicate reflected signals from each side 14, 15 and 16 of the target object 13, respectively. The reflected signal stored in the memory 6 is transmitted to a small electronic computer 6.
reflected signals 37, 38, 39 shown in Figure 3.
propagation time of 4°, 41.42 and reflected signal strength of 43.4
4. 45 〇 Also, in FIG.
1 and a pulse motor 10 to rotate and scan in the directions of arrows A and B.

Figure 4 shows the detection of the propagation time and intensity of the reflected signal between the objects to be measured while stepping the ultrasonic transceiver element 1 at a predetermined angle. The intensity of the reflected signal from the object to be measured 13 is plotted with the horizontal axis representing the rotation angle of the ultrasonic transceiver element and the vertical axis representing the reflected signal intensity. 46, 47, and 48 are organized reflection signals from each side 14, 15, and 16 of the object to be measured 13, respectively, and □ the ultrasonic wave transmitting/receiving element 1 when each reflected signal intensity is maximum. The direction of each side 14, 15, 16 of the object to be measured 13 is detected from the rotational scanning angle. Furthermore, since the distance to each side of the object to be measured can be obtained from the propagation time of the reflected signal described above, each side 13 of the object to be measured 13,
14 and 15 can be determined, and the position of the object to be measured 13 can be detected.

However, when a conventional position detection device is applied to detect the position of a hole, it is possible to detect the position of a large diameter hole;
In a small diameter hole, reflected signals from each side of the hole are superimposed, so there is a problem that position detection cannot be performed unless the attenuation of the ultrasonic wave transmitting/receiving element is significantly improved.

In order to solve the above-mentioned conventional problems, the present inventors have already proposed a shape detecting device for an object to be measured. FIG. 6 is a system diagram of an apparatus for detecting the shape of an object to be measured, which has already been proposed by the present inventors. Further, FIG. 6 is a perspective view when the present shape detection device is applied to detect the position of the hole 82. FIG. 7 is a plan view of the same. In FIG. 6, the ultrasonic transmitting/receiving element 3 is attached to the manipulator 72 so as to face the target object 81 with an O1 inclination, and is moved in parallel in the X-axis direction.

In FIG. 6, 83 indicates the center position of the ultrasonic beam transmitted from the ultrasonic transceiver element 73, and the ultrasonic transceiver element 73 moves from the scanning start position 84 to the scanning end position 86 at regular distance intervals. Moves while transmitting and receiving waves. FIG. 8 shows the reflected signal intensity from the target object 81 when the ultrasonic transceiver element 73 is scanned in parallel in the X-axis direction, the horizontal axis is the amount of parallel scanning of the ultrasonic transceiver element 73, and the vertical axis is the reflected signal intensity. is plotted. Here, the amount of parallel scanning of the ultrasonic wave transmitting/receiving element 73 when the reflected signal intensity takes the minimum value is detected.
By adding the parallel scanning amount to the coordinates of the scanning start position 84 of the ultrasonic wave transmitting/receiving element 73, the center position of the hole 82 on the X-axis can be detected. The center position of the hole 82 on the Y-axis can also be detected in the same way.

On the other hand, when detecting the shape of a hole using the shape detection device configured as described above, it is difficult to realize the function of detecting the diameter information of the hole.

OBJECTS OF THE INVENTION An object of the invention is to eliminate the above-mentioned problems in detecting the shape of an object to be measured using the ultrasonic transceiver element and to provide a method for detecting diameter information of an object to be measured.

Structure of the Invention The present invention provides a method for changing the relative positional relationship between the ultrasonic transceiver element and the object to be measured, and transmitting and receiving ultrasonic waves by the ultrasonic transceiver element to obtain an intensity of a reflected signal from the object to be measured. The process of detecting the approximate curve coefficients near the minimum value and the process of detecting the shape of the object by comparing the coefficients of the approximate curve for each object stored in advance in a storage device. DESCRIPTION OF THE PREFERRED EMBODIMENTS A method for detecting diameter information of an object to be measured - Description of Embodiments A first embodiment of the present invention will be described below with reference to the drawings.

The schematic system diagram of the hole shape detection device according to the first embodiment of the present invention is the same as that shown in FIG. 5 described above, and its configuration will be described below.

In FIG. 5, 72 is a means (hereinafter referred to as a manipulator) for changing the relative positional relationship between the object to be measured and an ultrasonic wave transmitting/receiving element (hereinafter referred to as an ultrasonic transducer), and is controlled by a control signal from the data processing control device 7O. The operation is controlled via a manipulator control device 71. Further, an ultrasonic transducer 73 for transmitting and receiving waves is installed on the manipulator 72.

The ultrasonic transducer 73 uses an oscillator 8O to transmit ultrasonic waves of a predetermined frequency toward a target object, and receives a reflected signal thereof. Ultrasonic transducer 73
The transfer signal outputted by the converter passes through a received signal amplifier 74, is converted into a digital value by an analog-to-digital converter-r5 (referred to as a %A/D converter), and is stored in a memory 76.

Furthermore, a data processing control device 7o is provided.

This data processing control device 7o is composed of an interface control unit 77 (hereinafter referred to as ICU), a front desk drive device 78 (hereinafter referred to as FDD), and a small electronic computer 79 (hereinafter referred to as CPU). The ICU 77 is connected to the FDI 7B and the CPU 79, and the 0FDD 78, which is connected to the oscillator 8O and the memory 76, inputs a program or various conditions for performing position detection using this position detection device. This data processing control device 70 outputs control signals for operating the oscillator 80 and outputs control signals to the manipulator control device 1 for controlling the operation of the manipulator 72, and also transfers human power data from the memory 76. The CPU 79 detects the reflected signal intensity, calculates the position of the hole in the target object, and calculates the amount of movement of the manipulator 72 according to the nfC program input in advance from the FDD 78.

Next, we will explain the entire operation of the shape detection device configured as above.In this embodiment, the diameter of the ultrasonic transducer 73 shown in FIGS. 6 and 7 is 36 lungs, and the target object 81 and the ultrasonic The distance between the transducer 73 is 75 mm and the diameter of the hole 82 in the target object 81 is 6111+I+, and the transmitting and receiving wave surface of the ultrasonic transducer 73 is aligned with the X axis of the target object 81 or [
A predetermined angle 61 with respect to the Y axis (Ifh'+ in this example)
O.) A case will be described in which the scanner is arranged so as to be inclined, and one parallel scan is performed in the stepwise X-axis or X-axis direction of 1Tm while maintaining a constant distance from the target object 81.

The shape detection program is carried out according to the procedure of the shape detection program shown in the flowchart of FIG. 9, which is pre-introduced from the shape detection i FDD 78. In the flowchart of FIG. The approximate curve coefficients for each detection hole diameter are stored internally. In this embodiment, the transmitting/receiving surface of the ultrasonic transducer 73 is tilted at a predetermined angle θ (1o0 in this embodiment) in the scanning direction with respect to the target object 81, so that the center of the ultrasonic beam is at a distance between 75 and 75. After detecting the minimum value of the reflected signal intensity obtained by parallel scanning through the center position of a certain detection hole, interpolation processing using quadratic regression is performed on the vicinity of the minimum value, resulting in a quadratic curve. (y=ax+bx+c)+7) The coefficient a of the quadratic equation is memorized, and when the diameter of the detection hole 82 is between 5 and 5, a=152. If the diameter is 41+I+I+, it is a-96. If the diameter is 3-, it is a-47. Next, in step 2, the data processing control device 70 controls the manbulator control device 71 to
- move the ultrasonic transducer 73 to the sensing start position 84 by driving the transducer 72; At this time, the wave transmitting/receiving surface of the ultrasonic transducer 73 is inclined by 100 fp in the X-axis direction with respect to the target object 81. In FIG. 6, 83 indicates the center position of the ultrasonic beam transmitted from the ultrasonic transducer 73.
-jfc85 indicates the intersection of the center position of the ultrasonic beam and the target object 81 when sensing is completed, and sensing in the X-axis direction is performed within this section. In the embodiment, the sensing interval is 10 times.

Next, in step 3, the oscillator 80 is operated by the control signal from the data processing control device 7O, and the ultrasonic transducer 73 transmits ultrasonic waves of a predetermined frequency toward the object to be measured 81. At the same time, A/D conversion is performed. Vessel 76/Memo IJ 7
6 is operated to store the reflected signal from the target object 81 in the memory 76. In FIG. 10, the reflected signal intensity stored in the memory 76 90 indicates the reflected signal from the target object 81. In FIG.

Next, in step 4, the ninth-order reflected signal 1I is stored in the memory 76.
The signal is transferred to the CPU 79 via the CU 77, and the CPU 79 detects the reflected signal intensity Pl of the reflected signal 9o from the target object 81 according to a program preloaded from the FDD 78.

Next, in step 6, the manipulator 72'i is moved 1fi in the X-axis direction, and the steps 2 and 9 are repeated to complete the predetermined number of sensing operations (10 times in this embodiment), and then the process proceeds to step 6. In the tube 6, the detection target hole 82 is detected based on the intensity of the reflected signal from the target object 81 including the detection target hole 82 obtained in steps 2 and 3 above.
Detect the center position of In Figure 11, the diameter is 3611II.
++ ultrasonic transducer 73 to the target object.

01-100 The reflected signal intensity from the target object 81 when tilted and parallel scanned in the X-axis direction, the horizontal axis is the parallel scanning amount of the ultrasonic transducer 73, and the vertical axis is the reflected signal intensity. Every point is a pro 9.
Then, according to the program inputted in advance from the FDD 78, all the minimum values of the reflected signal intensity are detected to detect the center position of the hole 82 in the X-axis direction.Next, in step 7, the manipulator is used to sense the Y-axis direction. 72 to operate the ultrasonic transducer 73
Move to the sensing start position on the Y axis. At this time, the X coordinate of the intersection between the center position of the ultrasonic beam and the target object 81 is set to be the same as the center position coordinate of the hole 82 detected by sensing in the X-axis direction described above. Further, the wave transmitting/receiving surface of the ultrasonic transducer 73 is inclined by 100 in the Y-axis direction with respect to the target object 81. In FIG. 6, 86 indicates the intersection of the center position of the ultrasonic beam and the target object 21 at the start of one sensing, and 87 indicates the intersection of the center position of the ultrasonic beam and the target object 21 at the end of sensing, and sensing in the Y-axis direction is performed within this section. Note that in this embodiment, the sensing section is 10M.

Next step 3.4. 5.6, the ultrasonic transducer 73 is
The center position of the hole 82 in the Y-axis direction is detected based on the intensity of the reflected signal obtained by parallel scanning in the axial direction.

Next, in step 8, diameter information of the hole 82 is detected based on the reflected signal intensity including the reflected signal from the center position of the hole 82 of the target object 81 obtained by the above-described sensing in the Y-axis direction. FIG. 12 shows the ultrasonic transducer 7 S f
The reflected signal intensity from the target object 81 when parallel scanned in the Y-axis direction is plotted with the Y-axis parallel scanning amount of the ultrasonic transducer 73 on the horizontal axis and the reflected signal intensity on the vertical axis. In CPH10, after detecting the minimum value of the reflected signal intensity obtained by parallel scanning according to the program installed in advance from FDD60, quadratic regression was used for data at three points including the point showing the minimum value. Interpolation processing is performed to detect the coefficient a of the quadratic equation of the quadratic curve (y=ax+bx+c).

In FIG. 12, 91 is the result of interpolation processing using quadratic regression, and the coefficient a of the quadratic equation is 162.

By comparing this with the coefficient a of the quadratic equation stored in advance in step 1, it was possible to detect that the diameter of the hole 82 in the target object 81 was 61+Im. In this example, the hole 82 in the target object 81 The case where the diameter of the hole is 6 has been described, but if the diameter of the hole 82 is 4 mm +
In the case of 3+10++, when shape detection was performed according to the procedure of the shape detection program shown in the flowchart of Fig. 9, the coefficient of the quadratic equation was found to be f'L & = 9.
6, a = 47, and the diameter of the hole 82 could be detected.

Further, in this embodiment, the diameter of the hole 82 of the target object 81 is 5 mm*
Although the cases of 4 mm and 3 mm have been described, it goes without saying that if the coefficient ai of the quadratic equation is memorized for various hole diameters in step 1, hole diameters other than these can also be detected.

Effects of the Invention As described above, the present invention provides an object to be measured that is obtained by transmitting and receiving ultrasonic waves by changing the relative positional relationship between the ultrasonic transmitting and receiving element and the treasure to be measured. The coefficients of the approximation curve near the minimum value of the reflected signal intensity from Since the shape of the object is detected, a highly accurate shape detection method can be obtained, which has a great practical effect.

[Brief explanation of the drawing]

Figure 1 (1) is a system diagram showing the general configuration of a conventional ultrasonic shape detection device, Figure 2 is a perspective view of shape detection using the conventional device, and Figure 3 is a diagram showing operating waveforms of the conventional device. , 4th
Figure 6 is a diagram arranging the operating waveforms of the conventional device, Figure 6 is a system diagram showing the general configuration of the device for detecting the shape of the object to be measured, Figure 6 is a perspective view of the hole position detector, and Figure 7 is The same Moe drawing,
FIG. 8 is an explanatory diagram of operation waveforms, FIG. 9 is a flowchart showing an example of a program for hole position detection in the first embodiment of the present invention, and FIG. Figures 11 and 12 showing the operating waveforms of the device are as follows:
It is an explanatory diagram of the operation waveform.〇72"...Manbulator, 73...Ultrasonic e) Transducer, 79
...CPU, B2...hole. Name of agent: Patent attorney Toshio Nakao and one other person. Fig. 1 Fig. 2 Fig. 3 Fig. 4 Weak sound filter Q blue screen red scanning angle [pulling] Fig. 5 Fig. 6 Fig. 7 1/2 11/ Fig. 9 j~su's

Claims (1)

[Claims] An approximate curve near the minimum value of the reflected signal intensity from the object to be measured obtained by transmitting and receiving ultrasonic waves by the ultrasonic wave transmitting and receiving element while changing the relative positional relationship between the ultrasonic wave transmitting and receiving element and the object to be measured. A method for detecting the shape of an object to be measured, comprising the steps of: detecting the coefficients of the object to be measured; and detecting the shape of the object by comparing the coefficients of an approximate curve for each object stored in advance in a storage device. .