JPS633311A - Three-dimensional position detector - Google Patents

Abstract

PURPOSE:To improve the teaching efficiency and accuracy by controlling the relative position between a reference original point and each luminescent point with visual reference to the pictures displayed on a display monitor and then controlling the relative distance and the counter postures between a work and a head. CONSTITUTION:An operator looks at the screen of a display monitor 2 and a display unit 6 and at the same time operates a teaching pendant to move a teaching head 1 along the surface of a work 7 so that the coincidence is secured between a teaching point P0 and a reference original point 0 displayed fixedly on the monitor 2. When the coincidence is secured between the picture of the point P0 and the display position of the point 0, the head 1 is moved again to secure coincidence between the numeric value of a display unit 6 and the prescribed numeric value. When the relative position is set between the head 1 and the point P0, the positional relations between luminescent point S0-S4 and a reference straight line are controlled so that these relations have the same distances from each orthogonal reference axis. In such a way, the three-dimensional position of the head 1 is set.

Description

[Detailed Description of the Invention] [Object of the Invention] (Industrial Application Field) The present invention provides a method for adjusting the three-dimensional position of a head to a predetermined relative positional relationship with respect to a position setting point displayed on an object (workpiece). The present invention relates to a three-dimensional position detection device used when setting

(Prior art) For example, in an industrial robot installed in a part machining process, a material cutting process, a product assembly process, etc. on a production line, the work head is set on the robot before it actually operates. It is necessary to teach the movement path and operation procedure according to the three-dimensional shape of the workpiece. This work of teaching the three-dimensional movement of the work head is called teaching, and this teaching is generally performed by the operator's hands. For example, when teaching a CO2 laser cutting robot, the operator moves the machining head close to the teaching point of the trace line drawn on the surface of the workpiece while operating the teaching pendant, and then moves the machining head's tertiary direction toward the teaching point. Teaching is performed by setting the original position so that it has a predetermined relative positional relationship and storing three-dimensional positional information at this time.

However, in such conventional teaching work, the worker directly visually observes the relative positional relationship between the workpiece and the head, which requires time and effort for teaching, and also requires accurate (li2 installation window) The drawback is that it requires skill to configure.

Therefore, recently, in order to improve the efficiency of teaching work, for example, a magnetic sensor is placed near the processing head, and this magnetic sensor detects the eddy current generated in the workpiece to determine the Y1 distance between the head and the workpiece surface. is being carried out. However, when such a position setting device is used, although the opposing distance between the head and the workpiece can be easily determined, the attitude control of the head relative to the workpiece must still be determined visually by the operator. Therefore, a significant improvement in teaching head efficiency and accuracy could not be expected.

(Problems to be Solved by the Invention) As described above, in the conventional teaching work for robots, the work of approaching the teaching point was done visually and by trial and error, which not only required a lot of effort and time, but also Only a highly skilled person can perform accurate position setting. Furthermore, even if a magnetic sensor is used to detect the magnitude of eddy current generated in the workpiece and determine the facing distance between the workpiece and the head, the head posture control still has to rely on visual inspection, which makes teaching work difficult. Also, there was a problem that the accuracy could not be sufficiently increased.

SUMMARY OF THE INVENTION Therefore, an object of the present invention is to provide a three-dimensional position detection device that can perform teaching accurately in a similar amount of time and without requiring skill, thereby significantly improving the efficiency and accuracy of teaching work. do.

[Structure of the Invention (Means for Solving Problems)] In order to achieve the above object, the present invention sets the three-dimensional position of the head to a predetermined relative positional relationship with respect to the position setting point displayed on the object. In the three-dimensional position information Hffi,
A camera provided in the head to closely image the surface of the object, a display monitor to display images captured by the camera, and a distance measurement device attached to the head to measure the distance to the object. 1. At least three attitude control sensors attached to the head to control the attitude of the head, and generating a reference pattern of reference points and reference lines serving as alignment targets for the head main axis; A reference Bakun generating device, a reference point and a reference line generated by this reference pattern generating device are displayed on the display monitor, and each position information of the distance measurement sensor and the attitude control sensor is displayed on the screen of the display monitor. This configuration includes a signal processing device that displays the image as a bright spot on the top.

(Function) Therefore, in the three-dimensional position detecting device having such a configuration, the reference pattern of the reference points and reference lines that are the alignment targets of the head main axis generated by the reference pattern generator is displayed on the display monitor, and the reference pattern is used for distance measurement. Sensor and figure 9! ! I
Each position information of the sensor for 11111 is displayed as a bright spot on the screen of the display monitor, and the relative position of each bright spot and the reference origin is adjusted without visually checking the image on the display monitor to determine the position of the head relative to the workpiece. By adjusting the relative distance and facing attitude, the three-dimensional position of the head can be set accurately and with high precision.

(Example) An embodiment of the present invention will be described below with reference to the drawings.

FIG. 1 shows an example of the configuration of a three-dimensional position detection device according to the present invention. As shown in FIG. 1, the three-dimensional position detecting device according to this embodiment is composed of a teaching head 1 and a CRT display that displays an image signal taken by a camera provided in the teaching head 1, the details of which will be described later. A few drops of the display monitor 2, the reference pattern generation circuit 3 that generates a reference position pattern on the monitor 2, and the opposing distance and opposing position to the workpiece 7 detected by the touch sensor attached to the teaching head 1. A display unit 6 that displays the value as shown in FIG. It consists of a microprocessor 4 that converts into

The teaching head 1 is attached with one distance-measuring touch sensor 8 and four attitude-control touch sensors 12 each consisting of, for example, a potentiometer. As shown in FIG. 2, the distance measuring touch sensor 8 is attached to the outer peripheral surface of the head housing 16 corresponding to the workpiece 7, and a holder is attached at α6 position, which is 180 degrees different from this. 9 is installed. A substantially U-shaped arm 10 is provided between the distance fenestration touch sensor 8 and the holder 9, and the - one leg of the arm 10 is inserted into the hollow part of the distance measurement touch sensor 8, while the other leg is inserted into the hollow part of the distance measurement touch sensor 8. The legs of the arm 10 are inserted into the hollow part of the holder 9, and the arm 10 can move up and down with respect to the distance measuring touch sensor 8 and the holder 9. A contact probe 11 is attached to the tip of a rod that hangs down from the center of the arm 10.

Furthermore, the four posture control touch sensors 12 are held by sensor holders 18 that are respectively attached at appropriate intervals to appropriate parts of the inner wall surface of the head housing 16. Similarly to the above, a rod having a contact probe 11 attached to its tip is inserted through the rod so as to be movable up and down. Therefore, depending on the position where the welding probe 11 of the distance measuring touch sensor 8 contacts the workpiece 7, the arm 10
When the rod moves up and down depending on the position where the contact probe 11 of the attitude control head 12 contacts the workpiece 7, the distance setting touch sensor 8 and the attitude control touch sensor 12 move the distance setting touch sensor 8 and the attitude control touch sensor 12 relative to the workpiece 7. An electrical signal corresponding to the opposing distance and opposing position of the head 1 is input to the display unit 6, where the electrical signal is displayed as a numerical value indicating the opposing distance and opposing position with respect to the workpiece 8.

Furthermore, the teaching head 1 includes a semiconductor laser device 4 which illuminates the surface of the workpiece 7 on the inner wall surface of the head housing 16.
The peripheral illumination light sources 13 are each held by one light source holder provided at appropriate intervals.

Furthermore, a solid-state image sensor CC is located in the center of the head housing 16.
A camera 15 with a built-in D15a is attached by a camera holder 17, and this camera 15 is connected to the illumination light source 1.
Monitor 2 displays the surface condition of workpiece 7 illuminated by
It is something that is reflected in the image. In addition, 14 is a base for attaching the head housing 16, 20 is a dustproof optical filter, 2
Reference numeral 1 denotes a signal line cable for transmitting the video signal captured by the camera 15.

The reference pattern generating circuit 3 generates two orthogonal straight lines used to control the facing attitude with respect to the workpiece 7, and these straight lines are arranged at predetermined positions on the screen of the display monitor 2 as shown in FIG. The intersection point of the two straight lines is the origin of the head posture ill m. In addition, the A/D converter 5 converts the position information displayed on the display unit 6 into A/D.
Further, the microprocessor 4 processes the position information of the distance 31Il measurement touch sensor 8 and the attitude control touch sensor 12 output from the A/D converter 5 to display the position information on the reference straight line of the display monitor 2. It is displayed as a bright spot.

Next, the operation of the apparatus of this embodiment configured as described above will be explained in accordance with the order of position setting operations.
For the teaching point Pa on the scale IK displayed on the surface of
An example of setting the three-dimensional position of the teaching head 1 will be described.

Now, on the display screen of the display monitor 2, two orthogonal straight lines generated from the reference pattern generation circuit 3 and their intersections are displayed fixed at a predetermined position as shown in FIG. do. In this state, when the operator operates the teaching pendant and touches the workpiece 7 with the contact probe 11 provided on the distance measuring touch sensor 8, a numerical value is displayed on the display unit 6. The distance between the teaching head 1 and the surface of the workpiece 7 can be set at a predetermined position based on this value.

- On the other hand, the probe 11 provided on the touch sensor 12 for posture control also comes into contact with the surface of the workpiece 7, and the numerical values are displayed as 81 to S4 on the display unit 6, and at the same time the A/D converter 5 and the microprocessor 4, the bright spots S1 to S4 are also displayed on the display monitor 2.

Now, in this state, the operator operates the teaching pendant while visually checking the screen of the display monitor 2 and the display unit 6 to teach the teaching point Pa to match the reference origin O fixedly displayed on the display monitor 2. The head 1 is moved along the surface of the workpiece 7. Then, when the display position of the reference origin O coincides with the first stroke of the teaching point Pa, the teaching head 1 is moved again so that the numerical value on the display unit 6 coincides with a predetermined numerical value.

When the setting of the facing distance between the teaching head 1 and the teaching point PG is completed in this way, the operator moves to the bright points So to S4.
The posture of the teaching head 1 with respect to the workpiece is determined from the positional relationship between these bright spots Sa to S4 and the two orthogonal lines used as references, and the teaching pendant is operated while visually observing the screen of the display monitor 2. Each of the above bright spots So
~Adjust so that the positional relationship between S4 and the reference straight line is equidistant with respect to each orthogonal reference axis.

For example, FIG. 3(a) shows a case where the workpiece 7 is a flat surface,
If the posture of the teaching head 1 is adjusted so that Sl, S3, S2, and S4 are equidistant from the origin as shown in FIG. It can be determined that the person is taking a posture.

Next, in the case of Fig. 4(a), the surface of the workpiece 7 is a cylindrical convex surface, and the bright spots S and S3 are equidistant from the origin, but 82.34 is shifted to the left on the screen. There is. in this case,
Judging that the teaching head 1 is tilted to the right with respect to the normal line of the workpiece 7, the operator operates the teaching pendant to change the state from the state shown in FIG. 4(b) to the state shown in FIG. 5(b). By adjusting S2.84 so that it is equidistant from the reference origin ○, it is possible to control the teaching direction in the normal direction to the workpiece 7 including the teaching rod 1 as shown in FIG.

In addition, although Fig. 6 (a) shows the case where the surface of the workpiece 7 is a cylindrical concave surface, by the same operation as in the case of the convex surface described above, S2 and S4 shown in Fig. 6 (b) are placed equidistant from the reference origin ○. By adjusting so that teaching head 1
The posture of the workpiece 7 can be controlled in the normal direction to the workpiece 7.

Furthermore, although the example in FIG. 7(a) is a case where the workpiece 7 is a three-dimensional curved surface, the bright spot St as shown in FIG. 7(b).

The teaching pendant can be used to adjust the teaching pendant so that S3 and the bright spot S2.84 are equidistant from the reference origin 0, and the teaching head 1 can be controlled to be in the normal direction to the workpiece 7.

In this embodiment, the operator can use the display unit 6
The three-dimensional position of the teaching head 1 with respect to the surface of the workpiece 7 can be controlled by operating the teaching pendant while visually observing the numerical value of and the position of the bright spot Sl to $4 on the display monitor 2. As a result, the facing distance Both the position and the facing position can be set accurately and in a short time without relying on the worker's ribs, thereby greatly improving the efficiency and accuracy of teaching.

It should be noted that the present invention is not limited to the embodiments described above and shown in the drawings, but can be implemented with various modifications without changing the gist thereof.For example, in the embodiments described above, the display monitor 2 and the display unit Although it is separate from 6,
By inputting the input signal to the display unit to the display monitor 2 and displaying the numeric position, both can be integrated. Further, although the facing distance and the facing fiL position with respect to the work surface are detected by the touch sensor, a proximity switch may be used instead of the touch sensor, and the number of such switches is one distance measuring sensor and four. Although three or more posture control sensors are used, the object of the present invention can be achieved with any number of posture control sensors, as long as it is three or more. Furthermore, in the above embodiment, the case where the illumination light source is built into the head housing has been described, but an external light source may be used for illumination, and reference marks are provided on the two reference straight lines to facilitate adjustment work. You may try to make it easier. In addition, if a hole is made in the center of the probe 11 and the point P on the surface of the workpiece 7 can be photographed with a camera through this hole and viewed directly on the display monitor 2, the work efficiency of position setting will be increased. You can also do that.

Furthermore, the display monitor 2 is equipped with an image processing circuit and an arithmetic circuit, and this image processing circuit calculates the three-dimensional position of the teaching head 1 from the position coordinate values of each bright spot on the display screen, and quantitatively determines the position of the head relative to the workpiece. The facing posture may be determined and adjusted. It goes without saying that an industrial television camera may be used as the camera, and a liquid crystal display other than a CRT may be used as the display monitor.

[Effects of the Invention] As detailed above, the present invention provides a three-dimensional position detection device that sets the three-dimensional position of a head in a predetermined relative positional relationship with respect to a position setting point displayed on a target object. a camera installed on the head to take an image of the surface of the object; a display monitor for displaying an image taken by the camera; a distance measurement sensor attached to the head for measuring the distance to the object; at least three attitude control sensors attached to the head for controlling the attitude of the head; a reference pattern generator for generating a reference pattern of reference points and reference lines serving as alignment targets for the head main axis; , a signal that causes the reference point and reference line generated by the reference pattern generator to be displayed on the display monitor, and also displays each position information of the distance measurement sensor and the attitude control sensor as a bright spot on the screen of the display monitor. The configuration includes a processing device that displays on a display monitor a reference pattern of reference points and reference lines that serve as alignment targets for the head main axis generated by a reference pattern generator, and also displays a distance measurement sensor and an attitude control sensor. Position information is displayed as bright spots on the screen of the display monitor, and the relative distance and facing attitude of the head to the workpiece are determined by adjusting the relative position of each bright spot and the reference origin without visually checking the image on the display monitor. By adjusting each, the three-dimensional position of the head can be set.

Therefore, according to the present invention having such a configuration, a three-dimensional position detection device that can perform teaching accurately in a short time and without requiring any skill, thereby greatly improving the efficiency and accuracy of teaching work. can be provided.

[Brief explanation of the drawing]

FIG. 1 is a perspective view showing the configuration of an embodiment of a three-dimensional position detecting device according to the present invention, and FIG. 2 is a perspective view showing the configuration of a teaching head in the same embodiment. Cross-sectional views in the direction of arrows, Fig. 3 (a>, (b) to Fig. 7 (a)
, (b) are for explaining the operation of the same embodiment, each figure (a) is a schematic diagram showing the positional relationship between the head and the workpiece, and each figure (b) is a display image on the display monitor. It is a schematic diagram. 1...Teaching head, 2...Display monitor, 3...Reference pattern generation circuit, 4...
...Microprocessor, 5...A/D
Converter, 6...Display unit, 7...
Workpiece, 8...Touch sensor for distance measurement, 9.
...Holding body, 1o...Arm, 11...
...Probe, 12...-touch sensor for posture control, 13...Light source for illumination, 14...
・Base, 15...Camera, 15a...
・Solid @ Machine element, 16...Head housing, 17.
...Camera holder, 18...Sensor holder, 19...Light source holder, 20...Optical filter, 21...Signal line cable. Application agent Patent attorney Takehiko Suzue 2nd figure (b) ≧1 (b) (b) Figure 2

Claims (1)

[Claims] A three-dimensional position detection device that sets the three-dimensional position of a head in a predetermined relative positional relationship with respect to a position setting point displayed on a target object, comprising: a camera provided in the head and configured to image the surface of the target object; a display monitor that displays an image captured by the head; a distance measurement sensor that is attached to the head and measures the distance to the object;
at least three attitude control sensors attached to the head to control the attitude of the head; a reference pattern generator that generates a reference pattern of reference points and reference lines that serve as alignment targets for the head main axis; Signal processing that causes the reference point and reference line generated by this reference pattern generator to be displayed on the display monitor, and also displays each position information of the distance measurement sensor and attitude control sensor as a bright spot on the screen of the display monitor. A three-dimensional position detection device comprising: