JPS59112207A - Two-dimensional position detector - Google Patents

Abstract

PURPOSE:To obtain a simple, small-sized two-dimensional position detector by arranging two rotating mirrors for making scans on a target at specific distance, and finding anticipated angles from those two points to the target and finding the two-dimensional position of the target. CONSTITUTION:When the reflecting surface of a rotating mirror 9 for optical- path switching faces the side of a rotating mirror 8-2 for target scanning, reflected light from the rotating mirror 8-2 is incident to a photodetecting element 3. A picture processor 5 detects whether the target is in the center of the photodetection surface of the photodetecting element 3 or not, and when not, the rotating mirror 8-2 is rotated by a driving motor 6 to detect an anticipated angle beta. Then, the rotating mirror 9 for optical-path switching is rotated until its reflecting surface faces the reflecting surface side of the other rotating mirror 8-1 for target scanning. Similarly, the anticipated angle alpha of the target P from where the mirror 8-1 is placed is found. Those anticipated angles alpha and beta are used to find the two-dimensional coordinates (x) and (y) of the target P.

Description

DETAILED DESCRIPTION OF THE INVENTION [Object of the Invention] The present invention relates to a two-dimensional position detection device used in mobile robots, industrial robots, and the like.

[Prior art]

Target position information is important information when detecting the current position of a mobile robot, moving toward a target, or grasping a target and carrying it to a predetermined position, which is one of the basic movements of industrial robots. Chill with one of the.

Therefore, as a means for detecting the relative position from the robot to the target object, a position detection device as shown in FIG. 1 has conventionally been used. In Figure 1, P is the target, 1 and 2 are IT
V [industrial camera] placed at a distant point, 3.4 is ITVl.

The planar bone optical element 5-1.5-2 incorporated in 2 is an image processing device that determines whether a target object P is located at the center of the light-receiving surfaces of the light-receiving elements 3 and 4. Further, as shown in FIG. 2, the ITVI, 2 is mounted so that the light receiving surface of the light receiving element 3.4 is on the axis of the drive motor 6 that rotates the ITV, and similarly the rotation angle of the ITV is detected. A detector 7 is also attached to the shaft of the drive motor 6.

In FIG. 1, if the image processing device does not determine whether or not the center of the target object is at the center of the light-receiving surfaces of the light-receiving elements 3 and 4, the drive motor 6 is driven to perform ITVI.

Rotate 2. For example, as shown in Figure 1, the angle α.

Assuming that a target exists at the center of the light-receiving surface at β, the position of the target P can be determined by well-known triangulation as follows. That is, the distance a from ITV1 to target P
is determined by equation (1) using the sine theorem.

Therefore, considering the coordinate system X-0-Y as shown in FIG. 1, the position coordinates X, y of the target P are (2).

It is obtained using equation (3).

However, in the conventional device as shown in Fig. 1, the image processing device is
Having two sets of 1.5-2 increases the position detection speed, but it requires two sets of expensive ITVs, and the memory capacity of the detection device is large to handle image data, so it requires two sets of image processing devices. Having one increases the cost of the position detection device and is not suitable as a position detection device for a robot that is introduced with the hope of saving labor or reducing the cost of the product.

[Purpose of the invention]

Therefore, it is an object of the present invention to provide an economical two-dimensional position detection device.

[Vote points for invention]

The present invention is characterized by a two-dimensional position detecting device configured with a single image processing device, which is shared in a time-division manner to detect the position of a target object.

[Embodiments of the invention]

Hereinafter, embodiments of the present invention will be described in detail using FIG. 3.

In FIG. 3, 1 is a planar fluorescent element incorporating I'l'V, 31dITVK, 5 is an image processing device that detects that there is an image on the light-receiving surface of the light-receiving element 3, and 8-1.8-2 A rotating mirror 9 for scanning a target that can be rotated around the axes r11 and r2 placed at two points separated by a distance, and 9 can be rotated around the origin O of the coordinate system X-0-Y shown in FIG. Moreover, it is a rotating mirror for optical path switching to allow only the reflected light from one of the rotating mirrors 8-1 and 8-2 to enter the light-receiving element 3. Furthermore, the rotating mirror 8-1, 8-2 for scanning the target object and the rotating mirror 8-2 for optical path switching are arranged so that the reflection of the mirror and the center of the blood mark coincide with the axis of the drive motor 6 that rotates the mirror, as shown in FIG. , is attached to the shaft of the drive motor 6 together with the mirror rotation angle detection device 7.

A method for detecting the position of the target P according to FIG. 3 will be described.

Now, assuming that the reflective surface of the rotating mirror 90 for optical path switching is facing the rotating mirror 5-8-2111 for target object set meals as shown by the solid line in FIG. The reflected light from 8-2 is incident. The image processing device 5 detects whether a target object is present at the center of the light receiving surface of the light receiving element 3. If it does not exist, the drive motor 6 rotates the target scanning rotating mirror 8-2.

For example, as shown in FIG.
When the angle between the vertical line of the reflecting surface of −2 and the X axis, that is, the rotation angle of the rotating mirror 8-2, becomes β/2, if the target P is present at the center of the light receiving surface, the target object scan Since the viewing angle β from the point where the rotating mirror 8-2 for scanning the target object has been detected, the rotating mirror 9 for optical path switching is then rotated by a predetermined angle θ to rotate the reflecting surface of the mirror for scanning the target object. Direct it toward the reflective surface of mirror 8-1. Then, the same process as above is performed to obtain the viewing angle α of the target P from the point where the target scanning rotating mirror 8-1 is placed. At this time,
The rotation angle of the rotating mirror 8-1 is α/2.

In this way, once the viewing angles α and β of the target P from the rotating mirror 8-1°8-2 for target scanning are found, the above-mentioned (
By using equations 1) to (3), the two-dimensional locus 1i1J X, y of the target object P can be determined. (1)～
Equation (3) can be easily calculated using a microcomputer or the like.

Furthermore, a rotary encoder, a potentiometer, or the like can be used as the rotation angle detector 7 of the rotating mirror for scanning the target object.

Next, as a method for determining whether the target object has come to the center of the light-receiving surface of the light-receiving element, for example, as shown in Figure 5, find the center of the object and check whether the center coincides with the center of the light-receiving surface. There are possible ways.

To find the center of the target, set the light receiving surface to N as shown in Figure 5.
The light receiving surface is divided into XM pixels and scanned in the scanning direction. As a result, both ends of the target object, that is, Llal I□
, the center of the object can be found by (I-t-+I-piece/2), and the difference d from the center position T of the light-receiving surface is d=T-(I-mount+■□piece/2 ... Mountain... Since it is obtained from (4), when d = Q, the center of the target and the center of the light receiving surface coincide.When d = 0, the rotation of the rotating mirror for scanning the target is determined by the sign and size of dρ. The direction and rotation angle command values can be estimated and the drive motor can be driven.Other judgment methods include calculating the moment of the center line of the light receiving surface, or finding the center of gravity of the target and determining the center of gravity and the light receiving surface. There are methods for detecting coincidence of surface centers.

〔Effect of the invention〕

As explained above, the secondary position detection device according to the present invention can be configured easily and compactly.

[Brief explanation of drawings]

Fig. 1 shows a conventional two-dimensional position detection device, Fig. 2 shows an ITV rotating machine groove, Fig. 3 shows a two-dimensional position detection device according to an embodiment of the present invention, Fig. 4 shows a mirror rotation mechanism, and Fig. 5 FIG. 2 is an explanatory diagram of one method for determining whether or not a target object exists at the center of the light-receiving surface.

Claims (1)

[Claims] 1. Two sets of optical systems including a rotating mirror for scanning a target object and a mirror rotating detector working in conjunction with this mirror, a planar bone optical element, and the two sets of rotating mirrors. an optical path switching device that selects only the reflected light of one of the rotating mirrors from among the reflected lights and allows the light to enter the planar bone optical element; and detecting that an image is present on the light receiving surface of the planar bone optical element. and an image processing device, the two sets of rotating mirrors are arranged at a predetermined distance apart, and the two-dimensional position of the target is determined by determining the viewing angle to the target from these two points. Position detection device.