JPS61223505A - Apparatus for detecting position of fin - Google Patents

Abstract

PURPOSE:To detect the position and direction of an object with high accuracy within a short time, by detecting the positions of optical cutting lines and calculating the position, cross-sectional area and direction of the projection on the object from the distance between the detected positions. CONSTITUTION:Beams emitted from beam sources 8a, 8b are projected on a casting base material 1 by deflection scanning apparatus 12 through a projection mirror 13 to form cutting lines 14, 14b and condensed to the beam receiving surface of a two-dimensional semiconductive position decetector 16 by a lens 15 and the position signals (x), 9y) of an X-axis and Y-axis are outputted as beam spots in an interface circuit 20. The output signal (y) is separated into components dependent on the beam sources 8a, 8b by a sample hold circuit 21 and extracted to obtain position signals ya, yb detecting a fin 1a. a judge processing part 25 operates a differentiation value with respect to the detected signal ya, yb and said value is compared with a preliminarily given threshold value D to calculate the position corresponding to the fin 1a.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention is a flash position detection device, particularly in the trajectory control of a deburring robot, etc. This invention relates to an accurate detection device.

[Conventional technology]

The removal of castings, etc. is a work that is carried out in a harsh environment due to dust and noise, so mechanization using automatic machines such as industrial robots is required. In order to operate the tool optimally, it is necessary to accurately detect the position and shape of the burr formed on the casting.

Figure 5 is a perspective view of a conventional casting flash position detection device, which was published by Etchi, G.E., Werneck et al., entitled ``Smoothing of Castings by Sensor-Controlled Industrial Robots'', 1.
10th International Symposium on Industrial Robots in 980 (H*J,%rnecke etaA@CtAa
naming of casting mth 5e
nser-OontrsparsedIndustrialRo
bots', 10th International
aj 栖poaiun on Industryaj
Bobo-ts S 1980).

In the figure, (1) is the casting base material, and (1a) is the casting base material (
1) Streams generated on the top, (2) the entire casting beam position detection device, (4) the potentiometers installed in parallel between the frames (3) and (3a), and (5) the respective potentiometers. (4) rod, (6) is a contact attached to the tip of each rod (5), (7) is a potentiometer (4)
These are coil springs interposed between the contactor (6) and the contactor (6).

The conventional casting flash position detection device (2) is constructed as described above, and when each contactor (6) is pressed against the casting base material (1), the rod (5) detects the casting flash (corresponding to the 1aXD shape Cζ). The position of each contactor (6) follows the shape of the casting hole (1a).
) The contact (6) contacts the tip of the protrusion (5) of the rod (5).
Since the displacement is the maximum, if the potentiometer (4) shows the maximum value of displacement output is identified, the casting hole (1
0 position can be detected.

Further, by detecting the difference between the maximum value of the change output of this potentiometer (4) and the other potentiometers (4), the height of the casting hole (1a) from the casting base material (1) can be detected.

(Problems to be Solved by the Invention) The casting flash position detection device (2) using the conventional contact method as described above has the advantage of being simple and inexpensive, but due to long-term use, the contact (6) are worn out, and since each contact (6) is attached to the tip of the rod (5) of a parallel potentiometer (4), the contact (6)
A certain distance is required between them, resulting in very poor resolution.

In addition, there are various problems such as the inability to detect the direction in which the pouring (1a) is occurring.

This invention was made in order to solve this problem, and aims to provide a casting flash position detection device that can detect the casting flash shape and position as well as the direction of occurrence in a non-contact manner with high precision. purpose.

(Means for Solving Problem c) The casting beam position detection device according to Jin's invention includes a plurality of light sources and a condensed beam from these light sources that is deflected while projecting it onto the surface of a target object from an oblique direction. a deflection scanning device for scanning; a means for continuously detecting the two-dimensional position of the optical image formed on the surface of the target object by the scanning and outputting a position signal;
The apparatus includes a determination processing section that discriminates the peak signal from the output signal and calculates the cross-sectional area, position, and direction of the protrusion of the object based on the discriminated signal.

[Effect]

In the invention, since the object is scanned with condensed beams from a plurality of light sources using the same deflection scanning device, a plurality of light cutting lines are generated on the object during one scanning cycle. Therefore, the position, cross-sectional area, direction, etc. of the protrusion on the object can be calculated from the position detection of the optical cutting line and the distance image between the detected positions.

FIG. 1 is an explanatory diagram of an embodiment of the present invention.

In the figure, (8m) and (8b) are arranged facing each other,
The light sources (9a) = (9b), (10m), (10b) such as semiconductor lasers that are lit in a complementary manner convert the respective beams emitted from the light sources (8m) and (8b) into parallel lights. Convert = remade lens, (11) is a mirror that projects the beams emitted from the light sources (8a) and (8b) in the same direction.

A-yu is a deflection scanning device that scans multiple beams simultaneously.

A projection mirror (14a) projects the plurality of beams reflected from the deflection scanning device a toward the object from an oblique direction.
(14b) is a light cutting line generated on the surface of the casting base material (1) by the light sources (9a), (9b) and the deflection scanning device (2).

a! 9 is a condenser lens, and αe is a two-dimensional semiconductor device detection device.

A is a shape detection head in which each device (8&) to αe is housed, or a scanning drive device that drives one deflection scanning device a (11 is a light source (8m), complementary to (8b) Light source driving device for blinking, the handle is a two-dimensional semiconductor device detection device a
The interface circuit consists of an analog circuit that calculates the image position from the output of 0, and the sample hold that samples the output of the interface head in synchronization with the blinking operation signal of the light source drive unit.

(2) is a multiplexer, (to) is an analog-to-digital conversion 4S, (b) is a storage device, and (c) is a judgment processing section.

The flash position detection device configured as described above detects the position or shape of the flash by the operation described below.

The beams emitted from the light sources (8a), (8b) such as semiconductor lasers, = remate lenses (9a), (9b) s(
10a) It is converted into parallel light by s (10b) and projected in the same direction by a projection mirror (11), and is driven by a deflection scanning device α driven by a high-speed (100f(Z)) sine signal from a scanning drive device aQ. A light cutting line (14a) as shown in FIG. 1 is projected onto the casting base material (1) through a projection mirror (11).

FIG. 2 is a diagram showing the situation in which the light sources (8a) and (8b) on which semiconductor laser light or the like is projected are turned on in accordance with changes over time as described above. In the figure, symbol Ta indicates a drive signal that turns ON and OFF the light source (8aXD light source drive device) according to changes over time.

Also, symbol T Kamoma light source (8b) I7) Light source drive device α1 (
7) Indicates a drive signal that turns on and off. In this way, when the light source (8a) is 1 off, the light source (8b) is on, and the light sources (8a) and (8b) are lit in a complementary manner. (
The optical images of the optical cutting lines (14a) and (14b) formed by beams such as laser light from 8a) and (8b) are formed by the lens (
), the light is focused on the light receiving surface of the two-dimensional semiconductor device detector ae, and the interface circuit outputs X-axis and Y-axis position signals X and y as a light spot.

The line labeled y in Figure 82 shows the output signal y at this time. The output signal indicated by the line with symbol y is as follows.

Since components that respond to each of the light source (8a) and light source (8b) are mixed, the output signal y is a sample hold 0.
In step 1), the components existing in the light source (8&) and the light source (8b) are separated and extracted. Note that in order to separate and extract the output signal y with the sample hold (21), a light source (8a),
Since the light source drive signal (8b) is required, the light source drive device←l outputs the light source drive signals T& and Tb corresponding to the light sources (8a) and (8b), and the light source drive signal Ta
, Tb fall from the on state to sample the output signals X and y of the two-dimensional semiconductor device detector ae.

The symbol e shown in FIG. 2 indicates a state in which the output signal y is sampled at the sample hold (21) at the falling edge of the light source drive signal Ta when it changes from on to off. Further, the symbol f indicates a state in which the output signal y is sampled at the falling edge of the light source drive signal Tb when it changes from on to offI. Further, e' and fl correspond to symbols e and f. The signal separated and extracted by the sample-hold Q force in this way is represented by the symbol 1&e'lb in Figure 82.
The position signal will be as shown in the pattern below. Note that the output signal X of the two-dimensional semiconductor device detection device ae is similarly separated and extracted to obtain position signals Xa and Xb. The position signal obtained in this way.

""#3'a#)'bit w multiplexer (
2) and is selected at an appropriate timing by the selection signal given by the judgment processing section (to), and the selected position signal is sent to the analog-to-digital converter (to) and converted into a digital value. . And the digital value position data.

The data is stored in a storage device and analyzed as data for one scan by a judgment processing section.

In the above case, the position signals ya and yb that detected the casting hole (1&) in FIG.
The pattern jyl*1)j'h shown in FIGS.

The judgment processing unit (c) calculates the differential value of the detection signals ya and yb, and calculates the position corresponding to the casting hole (1a) by comparing the differential value with a predetermined threshold value. FIG. 3(B) shows a differential waveform of the detection signal differentiated by the judgment processing unit (c) (corresponding to the signal waveform Ya of Al. In the figure, Xm.

Xn+m indicates the positions of both ends of the differential waveform corresponding to the casting flash (1a) Iζ.

Next, the judgment processing unit (c) calculates the cross-sectional area of the casting hole (10) from both end positions - and
ltOt-Soerr(count=P"78 m J, is what is done.

Furthermore, xt=x%+i+1-X311l=o...
It is a road.

Furthermore, the judgment processing unit (c) calculates the center of gravity of the waveform ya in the interval [Xru,
ward, ■).

XS = c, x, o^Xi)/II −・・・−・
. . . ■ Fig. 4 shows a method of calculating the center of gravity value (XaJS) of this casting (1a).

Similar operations and calculations are also performed for waveform yb, and the center of gravity value (XS, yi) of the waveform corresponding to casting flash (1a) ζ in waveform ybtcb is calculated. As a result, the position of the casting hole (10) is determined by the center of gravity value (Xi, YC) of the casting hole (1a) in the waveform ya, and the direction of the casting hole (1a) is determined by setting the angle from the y-axis of the detected coordinates to θ. .

It is obtained from the following equation (4).

In the above embodiment, the case where the position and direction of the casting flash (1a) is detected has been described, but the present invention can similarly detect objects having other uneven shapes.

〔Effect of the invention〕

As explained above, in this invention, in order to scan a target object with condensed beams from a plurality of light sources using the same deflection scanning device, a plurality of light cutting lines are generated on the target object in one scan period. The position and direction of the object can be calculated in a short time by detecting the position of the optical cutting line and calculating the position cross-sectional area and direction of the protrusion on the object from the distance image between the detected positions. It has the effect of enabling high-precision detection.

[Brief explanation of drawings]

Figure #11 is a station diagram of an embodiment of the present invention, Figure 2 is a line diagram of drive signals of the light source driving device, and Figure 3 (AI is a line indicating the pattern of position signals shown in the storage device). figure,
Figure 3 (El is a diagram showing the differential waveform of the detection signal differentiated by the judgment processing section, Figure 4 is a diagram showing the calculation method for the center of gravity position of the casting flash, Figure 5 is the diagram showing the position of the conventional casting flash) It is a perspective view of an example of a detection device. In the figure, (1) is a casting base material, (1a) is a casting,
(8a) (8b) is a light source, (9a), (9b), (10
a), (10b) are collimating lenses, al) are mirrors, %υ is a deflection scanning device, (l is a projection mirror, (14)
a), (14b) are optical cutting lines, 1st is a condensing lens, aQ
is a two-dimensional semiconductor device detector, aη is a shape detection head,
aS is a scanning driver, a field is a light source driver, (to) is an interface circuit, al) is a sample hold, @ is a multiplexer, (2) is an analog-to-digital converter,
(F) is a storage device, and (C) is a judgment processing unit. In each figure, the same reference numerals indicate the same or corresponding parts. Agent: Patent Attorney Mitsuo Kimura Figure 1, Figure 21! 1 Timeline

Claims (1)

[Scope of Claims] A plurality of light sources, a deflection scanning device that deflects and scans a surface of an object while projecting a condensed beam from the light source from an obliquely upward direction, and a light beam that is imaged on the surface of the object. means for continuously detecting the two-dimensional position of the image and outputting a position signal; discriminating the peak of the signal from this output signal; and calculating the cross-sectional area of the protrusion on the object based on the discriminated signal; A casting flash position detection device comprising: a determination processing unit that calculates a position and a direction;