Robots – Counterbalance
Patent
1989-08-23
1993-03-02
Fleming, Michael R.
Robots
Counterbalance
395 86, 395 97, 901 3, G05B 1300, G05B 19415
Patent
active
051916398
DESCRIPTION:
BRIEF SUMMARY
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to a mirror image method for use in an industrial robot, and more particularly, to a method for preparing a mirror image program for mirror image drive.
2. Description of the Background Art
In an industrial robot, it is conventionally known to utilize a mirror image function of the robot so as to determine mirror image points of teaching points associated with one side of a work object. The determined mirror image points are used as teaching points associated with the other side of the work object. Operations, at opposite sides of the work object are carried out on the basis of the aforementioned two kinds of teaching points in a symmetrical manner with respect to a plane passing through an axis of the work object. As shown in FIG. 3, it is also known to symmetrically dispose, with respect to a work object 53 on a working line 52, a first robot 50 responsive to a teaching program, and a second robot 51 responsive to a program containing therein, as teaching points, mirror image points of teaching points contained in the teaching program. The robots 50 and 51 simultaneously carry out operations, symmetrical with each other with respect to the work object 53, at opposite sides of the work object 53.
Conventionally, in a robot of the above-mentioned type, a mirror image 54' of the position of a tool tip point 54 and a mirror image 55' of the position and attitude of a tool mounting center 55 are determined with respect to a mirror plane 56, as shown by way of example in FIG. 4. Then a program according to mirror images is prepared on the basis of these mirror images 54', 55' and a teaching program. In this respect, the conventional art entails drawbacks, e.g., the attitude of the mirror image T' is unsymmetrical with that of the tool T with respect to the mirror plane 56, as shown in FIG. 4.
SUMMARY OF THE INVENTION
The object of the present invention is to provide a mirror image method for use in a robot, which is capable of determining a mirror image attitude which is symmetrical with a tool attitude.
To achieve the aforementioned object, a mirror image method according to the present invention comprises steps of; (a) preparing a teaching program on the basis of teaching points represented by a first coordinate system; (b) setting a second coordinate system in a such a manner that two coordinate axes of said second coordinate system define a mirror plane; (c) effecting a coordinate transformation associated with a respective one of said teaching points from said first coordinate system to said second coordinate system; (d) determining, in said second coordinate system, a mirror image point which is symmetrical with said teaching point with respect to said mirror plane; and (e) effecting a coordinate transformation associated with said mirror image point from said second coordinate system to said first coordinate system.
According to the present invention, mirror image points in a second coordinate system, having two coordinate axes defining a mirror plane, are determined through a coordinate transformation, associated with a teaching point represented by a first coordinate system, from the first coordinate system to the second coordinate system. Then, a coordinate transformation, associated with a mirror image point, from the second coordinate system to the first coordinate system is carried out. Accordingly, it is possible to prepare a mirror image program and achieve mirror image drive, in which a mirror image attitude is symmetrical with a tool attitude.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a flowchart of a control program for executing a mirror image method according to an embodiment of the present invention;
FIG. 2 is a block diagram showing an essential part of an industrial robot to which the mirror image method of FIG. 1 is applied;
FIG. 3 is a schematic plane view showing, by way of example, an operation performed by a robot having a mirror image function; and
FIG. 4 is a schematic perspective view sho
REFERENCES:
patent: 4495588 (1985-01-01), Nio et al.
patent: 4613943 (1986-09-01), Miyake et al.
patent: 4639878 (1987-01-01), Day et al.
patent: 4683544 (1987-06-01), Hariki
Davis George
Fanuc Limited
Fleming Michael R.
LandOfFree
Mirror image method for use in a robot does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Mirror image method for use in a robot, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Mirror image method for use in a robot will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-132718