JPS6162808A - Apparatus for detecting position of object to be measured - Google Patents

Abstract

PURPOSE:To make it possible to detect the central position of a minute projection with high accuracy, by simple constitution such that the direction of an ultrasonic transducer is changed to detect a position where the reflected wave from an objective body takes a max. value. CONSTITUTION:The ultrasonic transducer 53 of a manipulator 50 transmits a predetermined ultrasonic wave to an objective body by an oscillator 55 and receives the reflected signal thereof. The manipulator 50 is made operable in X-and Y-axis directions by a manipulator control apparatus 52 and the center position of the minute projection of the objective body is detected from the change amount of the relative positional relation of the ultrasonic transducer 53 and the objective body when a receiving signal shows a max. value.

Description

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

Configuration of the conventional example and its problems A conventional position detection device for a measured object detects the circumference of the measured object from the maximum value of the reflected signal obtained by rotationally scanning an ultrasonic wave transmitting/receiving element with respect to the measured object. There is a device that detects the position and orientation of the object to be measured by detecting the azimuth angle and the distance from the propagation time of the reflected signal to the periphery of the object to be measured. The outline of the contents will be explained below.

FIG. 1 is a stem diagram showing the general configuration of a conventional device. FIG. 2 is a perspective view showing shape detection using a conventional device. When a high voltage pulse 17 shown in FIG. 3 is applied to the ultrasonic transceiver element 1 in FIG. 1, an ultrasonic pulse of a predetermined frequency is emitted into the air. This ultrasonic pulse is reflected by the target object 13 in FIG.
After reaching the receiving signal amplifier 3 and being amplified, the signal is analog-to-digital converted and stored in the memory 15 . FIG. 3 shows operating waveforms of the ultrasonic transceiver element 1 stored in the memory 16, where 37°, 38.39 indicate reflected signals from each side of the target object 13 at 14°, 16.16, respectively.

The reflected signals stored in the memory 16 are transferred to the small computer 6, and the propagation times 40, 41, 42 and reflected signal strengths 43.4 of the reflected signals 37, 38, and 39 shown in FIG.
4.45 is detected.

1. In FIG.
The configuration is such that the ultrasonic transceiver element 1 is rotated and scanned in the directions of arrows A and B via the pulse motor 1o, and the propagation time of the reflected signal and 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 vertical axis represents the reflected signal strength. 46, 47, and 48 are the reflected signals from each side 14, 15, and 16 of the object to be measured 13, respectively, and are the rotational scans of the ultrasonic transceiver element 1 when the respective reflected signal strengths are maximum. Each side 14 of the object to be measured 13 from the angle
, 15.16 directions are 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 described above, the coordinates of each side 13, 14, 15 of the object to be measured 13 can be determined, and the position and orientation of the object to be measured 13 can be determined. can be detected.

However, in order to apply the above-mentioned conventional position detection device to detect the position of minute protrusions and obtain changes in reflected signal intensity corresponding to the presence of minute protrusions, it is necessary to significantly improve the attenuation of the ultrasonic transceiver element. Fortune-telling was necessary.

The present inventors have made extensive studies on a device for detecting the position of these minute protrusions, and have used an ultrasonic transceiver element to transmit and receive ultrasonic waves to and from the minute protrusions. Focusing on the fact that the reflected signal intensity obtained by parallel scanning changes greatly due to the presence of the minute protrusions, The center position of the minute protrusion can be detected from the amount of change in the relative position of the object, and the ultrasonic wave transmitting/receiving element is tilted with respect to the central axis of the minute protrusion and is set in a direction oblique to the minute protrusion. Focusing on the fact that the intensity of the reflected signal obtained by simultaneously transmitting and receiving ultrasonic waves and scanning parallel to the minute protrusions changes even more greatly due to the presence of the minute protrusions, The inventors have discovered that the center position of the minute protrusion can be detected from the amount of change in the relative position of the ultrasonic wave transmitting/receiving element and the minute protrusion when a value is indicated, and that all of the problems of the conventional structure described above can be solved, leading to the present invention. It was.

OBJECTS OF THE INVENTION It is an object of the present invention to eliminate the above-mentioned drawbacks and provide a simple structure.

Structure of the Invention The present invention provides a means for transmitting and receiving ultrasonic waves to an object to be measured using an ultrasonic wave transmitting/receiving element, a means for changing the relative positional relationship between the ultrasonic wave transmitting/receiving element and the object to be measured, and means for detecting the thickest value of the intensity of the reflected signal from the object to be measured so as to detect the position of the object by using changes in the intensity of the reflected signal near the center position of the object; An apparatus for detecting the position of the object to be measured, which is comprised of a signal processing means having a means for detecting the center position of the object from an amount of change in the relative positional relationship between an ultrasonic transceiver element and the object to be measured. It is.

DESCRIPTION OF EMBODIMENTS Hereinafter, embodiments of the present invention will be described with reference to the drawings.

FIG. 6 is a system diagram schematically showing a position detection device for a microprotrusion in an embodiment of the present invention. Further, FIG. 6 is a perspective view of a position W frame using a position detection device according to an embodiment of the present invention.
5 is the same plane M, and in FIG. 5, 50 refers to the minute protrusion 66 of the object to be measured C and below in this embodiment, the object 54. ) and the ultrasonic transducer element 53 (hereinafter referred to as the ultrasonic transducer) (hereinafter referred to as a manipulator). The operation is controlled by

On the manipulator 60, as shown in FIG. 6, an ultrasonic transducer 63 for both transmitting and receiving waves is installed. ! , the manipulator control device 62 is configured to be able to operate the manipulator 60 in two orthogonal axes, the X and Y axes.

The ultrasonic transducer 53 uses an oscillator 66 to transmit ultrasonic waves of a predetermined frequency toward a minute protrusion 65 of a target object 64, and receives the reflected signal. The received signal output from the ultrasonic transducer 63 passes through a received signal amplifier 66, is converted into a digital value by an analog-to-digital converter 57 (hereinafter referred to as an A/D converter), and is stored in a memory 58. . Furthermore, a data processing control device 61 is provided; however, this data processing control device 51
1d (interface control unit 69 (hereinafter referred to as work C)) floppy disk drive device 60 (
Hereinafter referred to as FDD. ) and a small electronic computer 61 (hereinafter referred to as CPU). ICU39 is FDD
60 and CPUel, and also connected to the aforementioned oscillator 55 and memory IJ58. The FDD 60 inputs a program or various conditions for performing position detection using this position detection device. This data processing control device 5
1, outputs a control signal for operating the oscillator 66, outputs a control signal to the manipulator control device 52 for controlling the operation of the manipulator 50, and preprocesses input data transferred from the memory 58, The C1PU 61 detects the reflected signal intensity, calculates the position of the minute protrusion of the target object, and performs calculations on the manipulator 6 according to a program pre-installed from the FDD 6o.
The amount of movement of o is calculated.

Next, the operation of the position detection device configured as described in Section 2 will be explained. In this embodiment, the diameter of the ultrasonic transducer 53 shown in FIGS. 6 and 7 is 36#1. Drive frequency is 66 KHz (wavelength λ-6,14 h), target object is 54
and the distance between the ultrasonic transducer 63 is 10011 m
+ The diameter of the minute protrusions 65 of the target object 64 is 2 and the height is 2, and the transmission/reception wave surface of the ultrasonic transducer 63 is at a predetermined angle θ with respect to the target object 54. A description will be given of a case where parallel scanning is performed while maintaining a constant distance from the target object 54 in steps of Q and 1711 m.

The position detection is performed in accordance with the procedure of the position detection program shown in the flowchart of FIG. 8, which is preloaded from the FDD 60. In the flowchart of FIG. 8, first, in step 1, the manipulator 60 is driven via the manipulator control device 62 by a control signal from the data processing control device 51, and the ultrasonic transducer 53 is set to the X-axis direction sensing start f device 63. Moving. In FIG. 6, 62 indicates the center position of the ultrasonic beam transmitted from the ultrasonic transducer 53, and 64 indicates the intersection of the center position 62 of the ultrasonic beam and the target object 54 when sensing is completed, and the X-axis Direction sensing is performed within this interval. In this embodiment, the sensing interval is 20 mm, and the sensing interval is determined so that the minute protrusion 65 is present within this interval.

Next, in step 2, the oscillator 55 is operated by the control signal from the data processing control device 61, and the ultrasonic transducer 53 transmits ultrasonic waves of a predetermined frequency toward the target object 54. At the same time, the A/D The converter 67 and the memory 68 are operated to store the reflected signal from the target object 64 in the memory 68. FIG. 9 shows the reflected signal stored in the memory 58.

Reference numeral 69 indicates a reflected signal from the target object 64.

Next, in step 3, the reflected signal stored in the memory 6B is
The CPU 61, which transfers the signal to cptrel via the CU 39, detects the reflected signal intensity P1 of the reflected signal 69 from the target object 64 according to a program installed in advance from the FDD 60.

Next, in step 4, move the manipulator 60 in the X-axis direction.
．． Move 1 mm and repeat step 2 above. When step 3 is repeated and a predetermined number of sensing operations (200 times in this embodiment) are completed, the process proceeds to step 5.

In step 6, the minute protrusion 66 to be detected is detected based on the intensity of the reflected signal from the target object 64 including the minute protrusion 66 to be detected obtained in step 2 and step 3 of ``2''.
Detect the center position in the X-axis direction. Figure 10 has a diameter of 3
6ffJ, driving frequency is 66 KHz (wavelength λ-5,
The intensity of the reflected signal from the target object 54 when the wave transmitting surface 66 of the ultrasonic transducer 63 of 14) is scanned parallel to the X-axis direction by θ1-100 in the X-axis direction with respect to the target object 64. , the scanning amount of the ultrasonic transducer 63 is plotted on the horizontal axis and the reflected signal intensity is plotted on the vertical axis every 10 points. Extreme value of signal strength and ultrasonic transducer 63 at this time
Detect the amount of parallel scanning. In FIG. 10, the hole detection sensitivity S1 was 8.8 dB.

Note that the hole detection sensitivity S is defined as follows.

That is, the minimum value of the reflected signal from the target object 54 is Pl,
If the maximum value of the reflected signal from the target object 54 is P2, the detection sensitivity S (dB) of the minute protrusion 66 to be detected is 5=20noq (P1/P2) (dB)
(1).

The parallel scanning amount of the ultrasonic transducer 63 at this time is 9.8T1m, and the center position of the detection target hole 66 in the X-axis direction is The above parallel scanning amount (9,8m
It could be detected by adding m).

Next, in step 6, it is determined whether sensing in the Y-axis direction necessary to detect the center position of the detection target hole 65 of the target object 64 has been completed.
In Steps 1 to 6, sensing in the Y-axis direction is performed similarly to the above-described sensing in the X-axis direction to detect the center position of the minute protrusion 66 to be detected.

In the Y-axis direction sensing, the wave transmitting/receiving surface 66 of the ultrasonic transducer 1-63 is tilted θ=100 in the Y-axis direction with respect to the target object 64 and scans parallel to the Y-axis direction. Center position 62 of the sound wave beam and target object 5
4 and the sensing start point 68 is set as the +nnning completion point, and sensing in the Y-axis direction is performed within this section where the minute protrusion 65 exists (20 mm in this embodiment).

FIG. 11 shows the intensity of the reflected signal from the target object 64 when the transmitting surface 66 of the ultrasonic transducer 53 is tilted by θ1-10° in the Y-axis direction and scanned parallel to the Y-axis direction. , the scanning amount of the ultrasonic transducer 53 is plotted on the horizontal axis, and the reflected signal intensity is plotted on the vertical axis every 10 points. The maximum value of and the amount of parallel scanning of the ultrasonic transducer 63 at this time are detected. In FIG. 11, the hole detection sensitivity S2 was 8.8 dB. Also at this time, the ultrasonic transgi
The center position of the detection target hole 65 in the Y-axis direction could be detected by adding the parallel scanning amount (14.2 mm) to the Y coordinate of the sensing start position 67 of the two ultrasonic transducers 63.

As described above, according to this embodiment, the wave transmitting/receiving surface 66 of the ultrasonic transducer 63 having a diameter of 36 mm is tilted by 100 degrees with respect to the target object 64 having the minute protrusions 65 to transmit ultrasonic waves with a driving frequency of 66 KHz. The intensity of the reflected signal from the target object-4 obtained by scanning the ultrasonic transducer 53 at a constant distance with respect to the target object 64 by operating the manipulator 50 at the same time as transmitting and receiving waves is determined by the ultrasonic transducer. The beam center position of 63 is the minute protrusion 6
5, the reflected signal strength increases significantly compared to the reflected signal strength when the beam center position of the ultrasonic transducer 53 is located further away than the microprotrusion 66. X of the minute protrusion 66 by detecting the amount of parallel scanning of the ultrasonic transducer 63 when .

The center position in the Y-axis direction could be detected, and a detection accuracy of 0.1 was obtained in this example.

In this embodiment, the object to be measured has been described as a minute protrusion 65 of the target object 54, but it may also be a band-shaped protrusion other than this embodiment provided on the target object 64. In short, the object to be measured is an ultrasonic transducer. If the intensity of the reflected signal obtained by transmitting and receiving ultrasonic waves by the ultrasonic transducer 53 by changing the relative positional relationship of the user 53 increases due to the presence of the object to be measured, the center position of the object can be detected. .

In this embodiment, the wave transmitting/receiving surface 66 of the ultrasonic transducer 63 is tilted 1o0 in the scanning direction with respect to the target object 64. The optimum value is given by the shape of 65, and in this example, 10° is the optimum value, and the shape of minute protrusion 6
The detection sensitivity 1is of 5 showed the maximum value.

Effects of the Invention As described above, in the present invention, an ultrasonic wave transmitting/receiving element transmits and receives ultrasonic waves to and from an object to be measured, and at the same time, the relative positional relationship of the ultrasonic wave transmitting/receiving element to the object to be measured is changed. The intensity of the reflected signal from the object to be measured, which is obtained by changing the intensity of the reflected signal from the object to be measured, changes in the vicinity of the center position of the object to be measured, and when this shows an extremely thick value, the relative positional relationship between the ultrasonic transceiver element and the object to be measured changes. Since the center position of the object to be measured is detected from the amount of change, a highly accurate position detection device can be obtained with a simple configuration, and its practical effects are great.

[Brief explanation of drawings]

Fig. 1 is a system block diagram showing the general configuration of a conventional ultrasonic position detection device, Fig. 2 is a perspective view of position detection using the conventional device, and Fig. 3 is a diagram showing operating waveforms of the conventional device. , FIG. 4 is a diagram arranging the operating waveforms of a conventional device, FIG. 5 is a system diagram showing a schematic configuration of the device in an embodiment of the present invention, and FIG. 6 is a diagram showing a microprotrusion in an embodiment of the present invention. 7 is a plan view of the same, FIG. 8 is a flowchart 1 diagram showing an example of a program for detecting the position of a microprotrusion in an embodiment of the present invention, and FIG. This figure shows the operating waveforms of the position detection device in the same embodiment of the present invention, and FIGS. 63 ・Ultrasonic transducer, 66 ・・Minute projection, 50 ・・Manipulator, 61 ・・・Data processing control device. Name of agent: Patent attorney Toshio Nakao and 1 other person No. 1
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Claims (3)

[Claims] (1) means for transmitting and receiving ultrasonic waves to and from the object to be measured using an ultrasonic wave transmitting and receiving element; means for changing the relative positional relationship between the ultrasonic wave transmitting and receiving element and the object to be measured; A means for detecting a maximum value of the intensity of the reflected signal from the object to be measured so as to detect the position of the object by using a change in the intensity of the reflected signal near the center position, the ultrasonic transceiver element, and the object to be measured. A position detecting device for an object to be measured, comprising a signal processing means having a means for detecting the center position of the object from the amount of change in the relative positional relationship of the objects. (2) The means for changing the relative positional relationship between the ultrasonic transmitting/receiving element and the object to be measured comprises means for moving the ultrasonic transmitting/receiving element parallel to the object to be measured. Measured object position detection device. (3) The device for detecting the position of a measured object according to claim 1, wherein the ultrasonic wave transmitting/receiving element is provided at an angle with respect to the central axis of the measured object.