JPS60131414A - Detecting method of position of object to be measured - Google Patents

Abstract

PURPOSE:To detect the position of a small-diameter hole at a high speed with high precision by detecting a center position in one axial direction from a reflected signal obtained by varying the relative position relation with an ultrasonic wave transmitting and receiving element and a center position in the other axial direction from plural ultrasonic transmitting and receiving elements. CONSTITUTION:While an ultrasonic wave transmitting and receiving element 53A sends an ultrasonic wave of specific frequency to an objective body 54, a reflected signal from the objective body 54 is stored in a memory 58. Then, it is transferred to a CPU61 through an interface control unit 59 to detect and store the level PA of the reflected signal 68 from the objective body 54. Further, ultrasonic wave transmitting and receiving elements 53B and 53C transmit an ultrasonic wave of specific frequency to the objective 54 and the levels PB and PC of reflected signals from the objective body 54 are stored. The center position of a hole 65 in an X-axial direction is detected on the basis of the level of the reflected signal 68 from the objective 54. Then the Y-axial center position of the hole 65 is detected on the basis of the levels P1, P2, and P3 of reflected signals from the hole 65.

Description

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

Conventional configuration and its problems The conventional method for detecting the shape of an object to be measured is to detect the position and orientation of the object from the reflected signal strength obtained by rotating and scanning an ultrasonic transceiver element with respect to the object. There are things that detect □. The outline of the contents will be explained below.

FIG. 1 is a system diagram showing the general configuration of a conventional device. FIG. 2 is a perspective view showing position detection using a conventional device. In FIG. 1, when a high voltage pulse 17 shown in FIG. 3 is applied to the ultrasonic transceiver element 1, an ultrasonic pulse of a predetermined frequency is emitted into the air. This ultrasonic beam is reflected by the target object 13 in FIG.
The reflected signal from 4, 15° 16 reaches the ultrasonic transceiver element 1, is amplified by the receiving signal amplifier 3, and then is converted into an analog signal.
It is digitally converted and stored in the memory 6. Figure 3 shows
It shows the operating waveforms of the ultrasonic transceiver element 1 stored in the memory 5, and shows the reflected signals from each side 14, 15, 16 of the target object 13, respectively. The reflected signal stored in the memory 5 is transferred to a small electronic computer 6, and the reflected signal 37. shown in FIG.
38,390 propagation time 40°41.42 and reflected signal strength 43,44.45 are detected.

In addition, in FIG.
1 and a pulse motor 1O in the directions of arrows A and B. While the ultrasonic transceiver element 1 is rotated at a predetermined angle, the propagation time of the reflected signal and the Detecting the intensity. FIG. 4 shows the rotation angle of the ultrasonic wave transmitting/receiving element, with the horizontal axis representing the intensity of the reflected signal from the object 13 when the ultrasonic wave transmitting/receiving element 1 is rotated and scanned.
The reflected signal intensity is plotted on the vertical axis.

46, 47, and 48 are each side 14 of the object to be measured 13, respectively.
15. The reflected signals from 16 are organized, and each side 1411 of the object to be measured 13 is calculated from the rotational scanning angle of the ultrasonic transceiver element 1 when the intensity of each reflected signal is maximum.
6.16 direction is detected. Furthermore, since the distance to each side of the object to be measured can be obtained from the propagation time of the reflected signal mentioned above, the coordinates of each side 13, 14, 15 of the object to be measured 13 can be determined, and the position of the object to be measured 13 can be determined. 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. Furthermore, when detecting the position of a large-diameter hole using the conventional example, it is necessary to rotate and scan the ultrasonic wave transmitting/receiving element 1 in two axes, which is a major problem in high-speed position detection of a large-diameter hole. It had become.

OBJECTS OF THE INVENTION It is an object of the present invention to eliminate the above-mentioned drawbacks and to provide a position detection method for detecting a large diameter position at high speed and with high accuracy.

Structure of the Invention The present invention changes the relative positional relationship of a plurality of ultrasonic wave transmitting/receiving elements arranged at predetermined intervals in one axis direction and the other axis perpendicular thereto, and a measured object in the one axis direction. detecting the central position of the object to be measured in one axial direction from a plurality of minimum values of the reflected signal intensity from the object to be measured, which are obtained by sequentially transmitting and receiving ultrasonic waves using the ultrasonic wave transmitting/receiving element; and detecting the center position of the other axial direction of the object to be measured from the minimum value of the plurality of minimum values, thereby obtaining a method for detecting the position of the object to be measured at high speed and with high accuracy. be.

DESCRIPTION OF EMBODIMENTS An embodiment of the present invention will be described below with reference to the drawings.

5A is a synumatic diagram schematically showing a position detection device for an object to be measured in an embodiment of the present invention. In Figure 5,
5O indicates the object to be measured and the ultrasonic transceiver elements 53A, 63. B,
53C (hereinafter referred to as a manipulator), and its operation is controlled via a manipulator control device 62 in response to a control signal from the data processing control device 51. In addition, ultrasonic wave transmitting/receiving elements 53 and 5
3B.

53G is installed on the manipulator 5○ as shown in FIG.

The ultrasonic transceiver elements 53A, 53B, and 53G are the oscillator 5
5, the ultrasonic waves of predetermined frequencies are sequentially transmitted toward the target object 64, and the reflected signals thereof are received. The received signals output by the ultrasonic transmitting/receiving elements 53453B and 5sc pass through the received signal amplifier 56, are converted into digital values by the analog-to-digital converter 57 (hereinafter referred to as MU/D converter), and are stored in the memory 58. be done. Furthermore, a data processing control device 51 is provided, and this data processing control device 51 is an ink face control /L/
It consists of a J-nit 59 (hereinafter referred to as XGU), a floppy disk drive device 60 (hereinafter referred to as FDD), and a small electronic computer 61 (hereinafter referred to as CPU). ICU39 has FDD6○ and CPU61
is connected to the oscillator 55 and the memo IJ5.
Connected to q. The FDD 60 inputs a program or various conditions for performing position detection using this position detection device. This data processing control device 61 outputs a control signal for selecting the ultrasonic transceiver elements 53 A, 53 B, and 53 Ci, outputs a control signal for operating the oscillator 55, and controls the operation of the manipulator 50. At the same time, the input data transferred from the memory 58 is preprocessed, and the CPU 61 detects the intensity of the reflected signal and determines the position of the object to be measured according to the program input from FDDeo in advance. , and the amount of movement of the manipulator 60.

Next, Fujiaki will explain the operation of the position detection device configured as described above. In this embodiment, a target object 54 and ultrasonic wave transmitting/receiving elements 53A and 53B shown in FIG.

53C distance is 100 words, measured object 6 on target object 54
5 (hereinafter referred to as a hole) has a diameter of 5u, and the wave transmitting/receiving surfaces of the ultrasonic wave transmitting/receiving elements 63A, 53B, 53G face the target object 54, and the ultrasonic wave transmitting/receiving elements 53A, 53B
, 53C in the Y-axis direction is 3B, and the ultrasonic wave transmitting/receiving elements 53A, 53B, 53G are explained in parallel to the target object 54 in two steps.

The position detection is carried out according to the procedure of the position detection program shown in the flowchart of FIG. 7, which is preloaded from the FDD 60. In flowchart ~1 in Figure 7,
First, in step 1, the manipulator 5o is driven by the control signal from the data processing control device 51 via the shim manipulator control device 52, and the ultrasonic wave transmitting/receiving elements 53 and 53B are
, 630 to the sensing start position.

In FIG. 6, 62mm, 62B, and 62Cij indicate the center positions of the ultrasonic beams transmitted from the ultrasonic wave transmitting/receiving elements 53mm, 53B, and 53G, respectively. Also 6 3 A, 6
3 B, 63 G are 64 people at the start of sensing,
64B and 64G indicate the intersection of the center position of the ultrasonic beam transmitted from the ultrasonic transmitting/receiving elements 53, 53B, and 53G and the target object 54 when sensing is completed, and sensing is performed within this section.

In this embodiment, the sensing section in the X-axis direction is 1QwI.
It is L.

Next, in step 2, the oscillator 66 is operated by the control signal from the data processing control device 51, and the ultrasonic wave transmitting/receiving element 53A is operated.
At the same time, the A/D converter 67 and the memory 68 are operated to store the reflected signal from the target object 64 in the memory 58. FIG. 8 shows the reflected signal stored in the memory 58. Reference numeral 68 indicates a reflected signal from the target object 54.

Next, the reflected signal stored in the memory 68 is transferred to the CPU 61 via the ICU 39. FDD in advance with CPU61
In accordance with the program installed from 60, the reflected signal intensities of the reflected signal 68 from the target object 64 are detected and stored.

Next, in steps 3 and 4, similarly to step 2 above, ultrasonic waves of a predetermined frequency are transmitted toward the target object 64 by the ultrasonic wave transmitting/receiving elements 53B and 53G, respectively, and a reflected signal of the reflected signal from the target object 54 is transmitted. Memorize the strength PR+PC.

Next, in step 6, if the predetermined number of sensing has not been completed, the manipulator 6o is moved in the direction of the arrow, and step 2. Step 3 - Repeat step 4. When the predetermined number of sensing operations (5 times in this embodiment) is completed, the process proceeds to step 6.

In step 6, step 2. Step 3゜Reflection signal 6 from target object 64 obtained by repeating step 4
The center position of the hole 65 in the X-axis direction is detected based on the reflected signal strength of 8. FIG. 9 shows the intensity of the reflected signal from the target object 64 when the ultrasonic transmitting/receiving element 53A is parallel scanned in the direction of the arrow, the horizontal axis is the amount of parallel scanning of the ultrasonic transmitting/receiving element 53A, and the vertical axis is the reflected signal. The CPU 61 performs an interpolation process using quadratic regression on the reflected signal intensity obtained by parallel scanning according to a program inputted in advance from the FDD 60, and calculates the minimum value of the reflected signal intensity. And the amount of parallel scanning of the ultrasonic wave transmitting/receiving element 63A at this time is detected.

In FIG. 9, 69 is the result of interpolation processing using quadratic regression, and the minimum value P1 of the reflected signal intensity from the apex of the oscillator curve 69 is 2.
1900 mV, and the parallel scanning amount of the ultrasonic wave transmitting/receiving element 53A at this time is 6M. The center position of the hole 65 in the X-axis direction can be detected by adding the above-mentioned parallel scanning amount (6 points) to the X-coordinate of the sensing start position of the ultrasonic wave transmitting/receiving element 53A.

Further, in the same manner, the minimum value P2 of the reflected signal intensity from the target object 54 when the ultrasonic wave transmitting/receiving elements 53B and 53G are scanned in parallel in the direction of arrow A. P3, and the amount of parallel scanning of the ultrasonic wave transmitting/receiving elements 53B and 53G at this time is also detected. In this example, the minimum value P2 is 7○O (mV), and P3 is 1,300 (
mV). Moreover, the parallel scanning amount was 6 cranes each.

Next, in step 7, the intensity of the reflected signal from the hole 65 obtained in step 6 described above is P1. P2. The center position of the hole 65 in the Y-axis direction is detected based on P5.

FIG. 10 shows ultrasonic wave transmitting/receiving elements s3A, 53B.

The horizontal axis represents the reflected signal intensity from the target object 64 including the hole 65 when the SaC is scanned in parallel in the direction of arrow A, and Y when the ultrasonic transceiver elements 63 A, 53 B, and 53 C are scanned in parallel.
The axis position is plotted with the minimum value of the reflected signal intensity taken on the vertical axis.

The CPU 61 calculates the minimum value Pj + P2 of the reflected signal strength according to the program input from the FDD 60 in advance.
An interpolation process using quadratic regression is performed on rP5 to detect the minimum value P4 of the reflected signal strength.

In FIG. 10, 76 is the interpolation result, and the minimum value P4 of the reflected signal intensity from the apex of the polygonal curve 75 is s o o mV, and the Y-axis position of the ultrasonic transceiver element 63 during parallel scanning at this time is 4. It was detected that the virus was infected. The center position of the hole 65 in the Y-axis direction could be detected by adding the Y-axis position to the X coordinate of the sensing start position of the ultrasonic wave transmitting/receiving element 53A.

Further, the center position of the hole 65 in the X-axis direction is the position of the ultrasonic wave transmitting/receiving element 53 when the intensity of each reflected signal obtained by sensing the ultrasonic wave transmitting/receiving elements 53A, 53B, and 53G shows a minimum value.
It can be detected by adding the average value of the parallel scan amount of A (6 tuna in this example) to the X coordinate of the sensing start position of the ultrasonic wave transmitting/receiving element 53A, as shown in FIG. The center position of the hole 65 shown in 0. was able to be detected.

As described above, according to this embodiment, the ultrasonic wave transmitting/receiving elements 63A and 63B are attached to the target object 64 having the hole 66.

53Ci is used to transmit and receive ultrasonic waves for scanning, interpolation processing is performed on the reflected signal intensity to detect the minimum values P1r, P2, p, and P3, and further, from these minimum values P4, the Y-axis direction of the hole 65 is determined. By detecting the center position of the hole 65 and also detecting the average value of the parallel scanning amount of the ultrasonic wave transmitting/receiving element 63 when the reflected signal intensity shows the minimum value in each parallel scan, the center position of the hole 65 ○1 can be detected, and in this example, a high positional accuracy of 0.05 m was achieved at 3.5.

Furthermore, the number of sensing times required to detect the position of the hole 65 in the sensing section (±5 m for both x and y axes) is 15 times, which is significantly reduced compared to the conventional example, and the hole position can be detected at high speed. was completed.

In this example, there are 53 ultrasonic wave transmitting and receiving elements.

Although the X coordinates of the scan start positions of 53B and 53G are the same, in this embodiment as well, if it is difficult to arrange the ultrasonic transmitting/receiving element when detecting a small diameter hole, a difference may occur. By adding the sensing start position to the calculated center position, the center position of the hole can be detected.

Effects of the Invention As described above, the present invention can reduce the minimum reflected signal intensity obtained by changing the relative positional relationship between the ultrasonic wave transmitting/receiving element and the object to be measured, as well as transmitting and receiving ultrasonic waves to and from the object to be measured. The central position of one of the axial directions of the object to be measured is detected from the value, and the relative positional relationship between the plurality of ultrasonic wave transmitting/receiving elements and the object to be measured is changed. Since the center position of the object to be measured is detected by detecting the minimum value of the minimum value and detecting the center position of the other axial direction of the object to be measured, the method of detecting the position of a small diameter hole with high speed and high accuracy can be performed. , its practical effects are enormous.

[Brief Description of the Drawings] Fig. 1 is a system diagram showing the general configuration of a conventional device for detecting the shape of an object to be measured, Fig. 2 is a perspective view of the conventional device, and Fig. 3 is an operating waveform of the conventional device. FIG. 4 is a diagram illustrating the operating waveforms of a conventional device, FIG. 5 is a system diagram showing a schematic configuration of a position detection device for an object to be measured in an embodiment of the present invention, and FIG. A perspective view of the device, FIG. 7 is a flowchart showing an example of a program for hole position detection, FIG. 8 is a diagram showing operating waveforms of the hole position detecting device, and FIG. 9 is a diagram showing operating waveforms and interpolation processing results. Figure 10 is a diagram showing the relationship between the amount of change and the minimum value of reflected signal intensity when the relative position of the ultrasonic transceiver element to the hole is changed in the Y-axis direction, and Figure 11 is a diagram showing the relationship between the minimum value of the reflected signal intensity and the Y axis of the hole. FIG. 3 is an explanatory diagram of a method for detecting the center position in the axial direction. 53A, 53B, 53G... Ultrasonic wave transmitting/receiving element, 65... Hole, 6o... Manipulator. Name of agent: Patent attorney Toshio Nakao and 1 other person
1 Figure 3 Figure 4 Figure #3 Ship investigation (Button 5 Figure 6 Figure 7) 8 Figure 9 No Taira Oj Cod Nene iff (
ml] Figure 10 Figure 11

Claims (1)

[Claims] A plurality of ultrasonic wave transmitting/receiving elements arranged at predetermined intervals in one axis direction and the other axis perpendicular thereto, and the relative positional relationship of the object to be measured is changed in the one axis direction to transmit and receive the ultrasonic waves. detecting the central position of one of the axial directions of the object to be measured from a plurality of minimum values of the reflected signal intensity from the object to be measured obtained by sequentially transmitting and receiving ultrasonic waves by the element; A method for detecting the position of an object to be measured, comprising the step of detecting the center position of the object to be measured in the other C-axis direction from a minimum value of a plurality of minimum values.