JPS60161093A - Method of detecting obstacle - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION [Technical field to which the invention pertains] The present invention relates to an obstacle detection method that plays an important role in determining the movement path of an arm of an intelligent robot.

[Problems with conventional technology]

In order to move the robot's arm to the destination without hitting any obstacles, there are two ways to do this. All I had to do was set a course.

In the case of ■, if the operating speed is fast like an industrial robot, the time from detection to collision is very short.
Avoid failure in that short time! It[11] must be performed, which is very difficult and therefore impractical.

In the case of (3), there is no means for detecting obstacles on the track, and the robot itself is not intelligent enough, so there is no robot that can automatically generate a route. It didn't exist.

[Purpose of the invention]

An object of the present invention is to provide an obstacle detection method that can detect the presence or absence of an obstacle on the route and obtain information on the position and size of the obstacle, which is essential when automatically generating a movement route for an arm. It is in.

[Summary of the invention]

The present invention relates to means for detecting the presence or absence of obstacles on the movement path of a robot arm, and includes a light beam emitting device and a light beam emitting device that scans the path of the robot from the start point to the end point so as to pass through the movement path of the robot. A W& structure and a means for scanning control, two television cameras for measuring the distance to the reflection source point of the light beam, and a distance calculation means for processing the image signal of the television camera and calculating the distance. The robot is constructed of an obstacle discriminating means for discriminating the presence or absence of an obstacle on the movement path of the robot.

Now, as shown in FIG.
) −.

Assume that the robot's hand moves along the top of the robot (assuming that
Scan from point S to point G so as to pass over Y+2)=Q. At this time, if there is an obstacle on the straight line f(x, y, z)-〇 whose size is so small that it can be ignored, one reflected light point will be formed on this straight line. but.

When there is no obstacle on this path, the distance at which one reflected light point is from P to the straight line f is determined by the position on f(xty+z)-0. ) can be made in a more distant place. Therefore, for example, Q
Use a range finder at point (x, y, z) to measure the distance to the ah reflected light point, and measure where this is located on the straight line '<xhy*z)-o to identify obstacles on the path. The presence or absence can be detected automatically.

〔Effect of the invention〕

According to the present invention, it is possible to easily realize an intelligent robot that can automatically generate a movement path for an arm.

[Embodiments of the invention]

Here, an embodiment of the present invention will be described in detail for the case where the coordinates of point P and point Q shown in FIG. 1 are the same, that is, the case where the scanning origin ρ of the light beam emitting device and the installation point of the range finder are the same.

FIG. 2 is a basic configuration diagram of the means necessary to put the present invention into practice. In one unit, 1 is a joint angle calculating means, 2 is a joint angle driving means, and 3 is an optical unit 31 that integrates two television cameras and an original beam emitting device, and processes a video signal obtained by the television camera. This distance measuring means includes a distance calculation means 32 that calculates the distance to the reflected light point. Reference numeral 4 denotes an obstacle discrimination means for determining the presence or absence of an obstacle on the robot's movement path and determining the position and size of the obstacle.

FIG. 3 is an external view of the optical system and its scanning mechanism.

Reference numeral 31 denotes an optical section, which includes television cameras 31a and 31b and a source beam radiating device 31c, and is configured such that the depression angle (or elevation angle) θ of the optical axis of the optical section can be changed by a motor 5 attached to a support fitting 7. 6 is an encoder for measuring θ. A motor 8 and an encoder 9 are inserted into and layered on the support 10, and the support metal fitting 7 is attached to the rotating shaft of the motor 8, so that the optical part rotates around the support.

Therefore, the optical axis azimuth angle φ of the optical section can also be adjusted by the motor 8. Now, given the coordinates of S and G and the robot path f that connects these two points, when the origin of the optical section 3 is at P, scanning is performed to ensure that the original beam passes through the path f from point S to G. The joint angles θ and φ of the mechanism and the distance l from the point P to the path f are determined by the joint angle calculating means shown in FIG.

When θ and φ are equal, the signal is sent to the joint angle driving means to rotate each joint by the specified amount. This part is.

The concept is almost the same as the continuous path (CP) control of conventional robots.

Then, the distance from the point Pxr to the reflected light point of the light beam is measured by the distance measuring means 3, and the measurement 1 [L and the previously determined l are compared by the obstacle discriminating means 4, L -1) g.・・・・・・・・・・・・1st formula or L
−1<a ・・・・・・・・・・・・Determine whether it is the second formula. Here, 6 is a positive constant, and is a number that should be determined based on the size of the part of the robot that must take into account collisions with obstacles.

In the case of the first formula, there is no fear of obstacles, and in the case of the second formula, there is a problem.

If there is an obstacle, the large amount of the obstacle can be calculated from the φ and θ of the section according to the conditions of the second equation.

Starting from this information, it is possible to automatically determine how to detour around the set route.

Figure 4 shows the operation flow.

In this practical example, in order to facilitate understanding of the intention of the invention, the robot's path was assumed to be a straight line, but it is of course possible to use a curved line ζ. The degree of freedom of the scanning mechanism can also be increased as required.

Furthermore, if the working range of the robot cannot be covered by one optical section and scanning mechanism, a plurality of optical sections and scanning mechanisms may be used by switching between them.

Furthermore, if a robot system has a stereoscopic vision system for object recognition, it can be used as a distance measurement means.

[Brief explanation of drawings]

Fig. 1 is a detailed explanation of the present invention, Fig. 2 is a basic configuration diagram necessary for putting the present invention into practice, Fig. 3 is a diagram showing an actual example of the optical section and scanning structure, and Fig. FIG. 4 shows the operational flow when the present invention is modified. 1... Joint angle calculation means, 2... Joint angle driving means, 3
. . . distance measuring means, 31 . . . optical section, 32 . . . distance calculation means, 4 . Representative Patent Attorney Nori Chika Wl Yu (and 1 other person) Figure 1 Figure 2 Figure 3 Figure 1 Figure 4

Claims (1)

[Claims] so that the light beam emitting device and the original beam of the original beam emitting device always pass through the movement path of the arm of the robot,
The robot includes a scanning mechanism that scans from a starting point to an ending point of a moving path of the arm of the robot, scanning control means that scans this scanning mechanism, and distance measuring means that measures the position of a reflected light point of the original beam. An obstacle detection method characterized in that the presence or absence of an obstacle on the movement path of the robot arm is determined and the size of the obstacle is determined.