JPS61120011A - Position detection device - Google Patents

Abstract

PURPOSE:To detect the corner part of an object with high precision by detecting the position of the corner part and by processing the level of a reflected signal obtained by transmitting and receiving an ultrasonic wave while varying the relative position relation between the object and an ultrasonic wave transmitting and receiving element at constant intervals of distance. CONSTITUTION:The received signal outputted by an ultrasonic wave transducer 53 is amplified 56 and converted by an A/D converter 57 into a digital value, which is stored in a memory 58. A data processing controller 51 consists of an interface control unit (ICU)59, a floppy disk drive (FDD), and a CPU61. The ICU59 is connected to the FDD60, the CPU61, an oscillator 55, and a memory 61. The data processing controller 51 outputs a control signal for operating the oscillator 55 and a control signal to a manipulator controller 52, and preprocesses input data from the memory 58, and the CPU61 detects the level of the reflected signal and performs the arithmetic processing of the position of the object an the arithmetic processing of the extent of movement of a manipulator 50.

Description

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

Configuration of the conventional example and its problems In the conventional production method, as shown in Fig. 1, the object 1
When the manipulator 3 performs work along the corner 2 of The information was entered in detail. However, the above configuration has the disadvantage that the jig for accurately positioning the object 1 at a predetermined position is expensive, and the manipulator 3
The disadvantage is that it takes a lot of time to input the position information of the object 1 into the controller. Moreover, when working with many types of objects, the above-mentioned drawbacks become even more serious.

Furthermore, as shown in Figure 1, if a positional error occurs in the shape of each corner or part of the object, if the manipulator is operated using NC data input to the manipulator controller in advance, it will follow the corner of the object. This had a major drawback in that it was impossible to do so, resulting in poor workmanship.

For this reason, the conventional ITV system has been proposed as a method to eliminate the above-mentioned drawbacks. This method optically inputs an image including the corner of the object using an ITV camera, and detects the angular position through image processing. It has the disadvantages of being susceptible to the effects of heat and being expensive, making it difficult to apply to manipulator work.

OBJECTS OF THE INVENTION It is an object of the present invention to eliminate the above-mentioned drawbacks and to provide a device capable of detecting the position of a corner of an object with high precision with a simple configuration.

Structure of the Invention The present invention provides means for determining a plurality of detection positions within a line segment connecting a work start point and a work end point on an object, and a means for determining a relative positional relationship between the object and an ultrasonic transceiver element at the detection positions. It consists of means for detecting and storing the position of a corner of the object by signal processing the reflected signal strength obtained by transmitting and receiving ultrasonic waves to and from the object while changing at constant distance intervals. ,
DESCRIPTION OF EMBODIMENTS Hereinafter, embodiments of the present invention will be described with reference to the drawings.

FIG. 2 is a system diagram schematically showing a position detecting device for a corner of an object according to an embodiment of the present invention.

Further, FIG. 3 is a perspective view of position detection using the position detection device according to the embodiment of the present invention, and FIG. 4 is a side view of the same.

In FIG. 3, 5o is a means (hereinafter referred to as a manipulator) for changing the relative positional relationship between the object 64 and the ultrasonic wave transmitting/receiving element 53 (hereinafter referred to as an ultrasonic transducer).

), whose operation is controlled by a control signal from a manipulator control device 61 via a manipulator control device 62. Also, on the manipulator 50, as shown in FIG. 53 is installed. Further, the manipulator control device 62 is configured to be able to operate the manipulator 6o in two orthogonal axes, the X and Y axes.

In FIG. 2, the ultrasonic transducer 53 uses an oscillator 65 to transmit ultrasonic waves of a predetermined frequency toward an object 64, and receives the reflected signal. Ultrasonic transducer? The received signal outputted by 53 passes through a received signal amplifier 66 and is then sent to an analog-to-digital converter 57 (hereinafter referred to as A/
It is called a D converter. ) is converted into a digital value and stored in the memory 68. Furthermore, the data processing control device 51
The data processing control device 61 includes an interface control unit 69 (hereinafter referred to as Icu), a floppy disk drive device 60 (hereinafter referred to as FDD), and a small electronic computer 61 (hereinafter referred to as CPU). ICU39 is FDDaO and C
It is connected to the PU 61 as well as the oscillator 66 and memory 68 described above. FDDaO 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 operating the oscillator 56.

It outputs a control signal to the manipulator control device 52 that controls the operation of the manipulator 50, and also performs preprocessing on input data transferred from the memory 68.
The CPU 61 detects the intensity of the reflected signal, calculates the position of the object, and calculates the amount of movement of the manipulator 60 according to a program previously input from D 6o.

Next, the operation of the position detection device configured as described above will be explained. In this embodiment, the diameter of the ultrasonic transducer 53 shown in FIG. 3 is 36 squares, and the driving frequency is 66 KH.
z (wavelength λ = 6.14 mm), the distance between the object 54 and the ultrasonic transducer 53 is 50 mm, and the transmitting and receiving wave surface of the ultrasonic transducer 53 is at a predetermined angle θ1 with respect to the object 64 (this implementation In the example, 100 in the y-axis direction)
A case in which they are arranged at an angle will be explained. Further, in this embodiment, it is assumed that the position of the corner of the object 54 is detected within the section from the work start point 62 to the work end point 63 in FIG.

The position detection is carried out according to the procedure of the position detection program shown in the flowchart of FIG. S, which is pre-installed from FDDeO. In the flowchart of FIG. 5, first, in step 1, an accurate corner position in the Y-axis direction is detected based on the approximate corner positions at the work start point 62 and work end point 63 that have been input in advance to the manipulator control device 52. First, in detecting the position of the corner of the object 640 at the work starting point e2, the manipulator 50 is driven via the manipulator control device 52 by a control signal from the data processing control device 61, and the beam center of the ultrasonic transducer 53 is moved. The object 540 moves to the corner detection start position. Note that the detection target section in corner position detection is set to be equally divided in the Y-axis direction centering on the Y coordinate of the corner detection position, and is 3o- in this embodiment. In Figure 4, 64
66 is the center position of the ultrasonic beam transmitted from the ultrasonic transducer 63 at the start of corner position detection, and 66 is the ultrasonic beam transmitted from the ultrasonic transducer 63 at the end of corner position detection. indicates the center position of In addition, the ultrasonic sampling pitch for corner position detection is 1 in this embodiment.
It is a.

Next, the oscillator 66 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 64. At the same time, the A/D converter 57. The memory 68 is operated to store the reflected signal from the object 54 in the memory 63. FIG. 6 shows the reflected signal stored in memory 68. Reference numeral 69 indicates a reflected signal from the object 64.

Next, the reflected signal stored in the memory 63 is transferred to the CPU 61 via the I'CU 59. FDD6 for CPUel
The reflected signal intensity P1 of the reflected signal 69 from the object 64 is detected according to a program pre-installed from 0. Below, the manipulator 60 is moved 11 in the Y-axis direction to detect the corner position at the work starting point 62 of the object 54.
n! D and sequentially detect the intensity of the reflected signal from the object 54 in the same manner as above. (In this embodiment, the number of samples of the reflected signal intensity is 31.) Next, the position of the corner of the object 54 in the Y-axis direction is calculated based on the reflected signal intensity obtained above. FIG. 7 shows the reflected signal intensity from the object 54 when the ultrasonic transducer 63 is scanned parallel to the object 64 in the Y-axis direction, and the horizontal axis shows the scanning amount of the ultrasonic transducer 63 and the vertical axis The reflected signal strength is plotted on the axis, and in the CPU61, the FDD
The maximum value of the reflected signal intensity and the amount of parallel scanning of the ultrasonic transducer 53 at this time are detected according to a program input in advance from 6Q.

In this embodiment, the parallel scanning amount of the ultrasonic transducer 63 is 1 when the reflected signal intensity shows the maximum value in FIG.
12ffllll+, and the position in the Y-axis direction of the corner at the work starting point 62 of the object 54 can be determined by adding the above-mentioned parallel scanning amount to the Y-coordinate at the start of detecting the corner position of the ultrasonic transducer 53. Detect, CPUel or FD
Store in D60.

Note that the Y-axis position of the corner at the work end point 63 of the object S4 is also detected and stored in the same manner as described above, although detailed explanation will be omitted.

Next, in step 2, the Y-axis of the corner of the object 64 within the section between the work start point 62 and the work end point 63 detected in step 1 is detected and stored. The position detection interval in the X-axis direction within this section can be freely determined depending on the tracking accuracy required for the corners of the object 54, and is set at 2ml1ll pinch in this embodiment.

Thereafter, when the corner detection position on the object 54 is moved by 2M in the X-axis direction, the Y-axis position of the corner is detected in the same manner as in step 1 above and stored in the CPU 61 or FDD 6o. FIG. 8 shows the X-axis position of the beam center of the ultrasonic transducer 63 on the horizontal axis, which is the Y-axis position of the corner of the object 64 obtained by executing step 2, and the Y-axis position of the detected corner on the vertical axis. This is a plot of the axis position.

As described above, according to this embodiment, the work line start point 62 and the work end point 63 can be included by simply inputting the approximate position information of the work line start point 62 and the work end point 63 on the object 64 into the manipulator control device 62 in advance. At each corner detection position within the section, the wave transmitting/receiving surface 66 of the ultrasonic transducer 53 with a diameter of 36 strokes is tilted by 100 degrees to transmit and receive ultrasonic waves with a driving frequency of 66 KH2, and at the same time, the manipulator 5o is operated to detect the object 54. Ultrasonic transducer 53
By detecting the amount of parallel scanning of the ultrasonic transducer 53 when the intensity of the reflected signal from the object 54, which is obtained by scanning the object 54 at a constant distance, shows the maximum value, In this example, the position coordinates of can be detected with high precision. - Detection accuracy for 3 cylinders was achieved.

Furthermore, by correcting the relative position amount of the manipulator 5o and the ultrasonic transducer 53 to the position coordinates of the corner of the object 54 detected above, the work start point 62 on the object 54 is reached to the end point 63 of the work. It was possible to detect the trajectory that the manipulator 6o should take within the section.

Note that in this example, the object is an object l having convex corners.
(Although this has been explained, the object may have a concave corner. In short, the object changes its relative position with the ultrasonic transducer 53 to transmit and receive ultrasonic waves by the ultrasonic transducer 53.) The position of the corner can be detected if the intensity of the reflected signal increases due to the presence of the object.

Effects of the Invention As described above, the present invention allows each corner within the section between the work start point and the work end point to be adjusted by simply inputting rough positional information regarding the work start point and work end point on the object into the manipulator control device in advance. While changing the relative positional relationship between the target object and the ultrasonic wave transmitting/receiving element at fixed distance intervals at the detection position, the reflected signal strength obtained by transmitting and receiving ultrasonic waves to and from the target object is subjected to signal processing. Since the position of the corner of the object is detected and stored, it is possible to obtain a highly accurate corner position detection device with a simple configuration, and its effects are impressive.

[Brief explanation of drawings]

FIG. 1 is a diagram showing a conventional working state for a corner of an object, FIG. 2 is a system diagram showing a schematic configuration of an apparatus according to an embodiment of the present invention, and FIG. 3 is a diagram showing a schematic configuration of an apparatus according to an embodiment of the present invention. A perspective view of the detection state of the corner position of the object, FIG. 4 is a side view of the same, and FIG.
FIG. 6 is a flowchart showing an example of a program for detecting the corner position of an object in an embodiment of the present invention.
The figure shows operational waveforms of the position detecting device in the same embodiment of the present invention, and FIGS. 7 and 8 are diagrams summarizing the operation of the position detecting device in the same embodiment of the present invention. 53... Ultrasonic transducer, 54...
...Object, 6o... Manipulator, 61.
...Data processing control device. Name of agent: Patent attorney Toshio Nakao, 1 person, 2,000 people
Figure 5 Medication delivery Figure b

Claims (1)

[Claims] means for determining a plurality of detection positions within a line segment connecting a work start point and a work end point on a target object; and a means for determining a plurality of detection positions within a line segment connecting a work start point and a work end point on an object; A position detection device comprising means for detecting and storing the position of a corner of the object by signal processing a reflected signal intensity obtained by transmitting and receiving ultrasonic waves to and from the object while changing the intensity.