JPH06171760A - Depalletization - Google Patents

Abstract

PURPOSE:To shorten the time for recognizing the position of a work by using a visual sensor for carrying out depalletization. CONSTITUTION:(a) The whole of one stage portion of the works piled on a pallet is recognized as one piece, and the positions of four apexes are obtained (Step S11). (b) The side of the whole of one stage portion of the works and the length of the diagonal line are obtained from the positions of four apexes which are obtained from the procedure (a), and compared with the previously inputted values, and it is judged if one stage portion of the works is in an arranged state or not (S12 and S13). (c) In case of arrangement, each position of the work is obtained from the positions of four apexes obtained by the procedure (a) and the previously inputted data such as the dimension of the work, and depalletizing is carried out (S14-S15). In case of disarrangement, each work is recognized and the position is obtained and depalletizing is carried out (S17-S19).

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a depalletizing method for recognizing the position of an object by a visual sensor and performing depalletizing (an operation of taking out works stacked on a pallet).

[0002]

2. Description of the Related Art FIG. 2 is a schematic configuration diagram showing a conventional depalletizing system, and FIG. 3 is an explanatory diagram showing a field of view of a camera in the system. 2 and 3, 1 is a robot, 2 is a robot controller, 3 is a calculation unit (image processing device) of a visual sensor, 4 is a camera of the visual sensor, 5 is recognized by the visual sensor, and depalletized by the robot 1. Work 6 is a pallet on which the work 5 is placed. Also, 7
Is the visual sensor field of view.

The conventional depalletizing system has the above-mentioned structure, and the work 5 is projected by the camera 4 of the visual sensor.
The position is calculated by the calculation unit 3 of the visual sensor, and the robot controller 2 controls the robot 1 based on the calculated position information to depalletize the work 5.

FIG. 4 is a flow chart showing the recognition procedure by the arithmetic unit 3 and the depalletizing procedure by the robot controller 2 of the conventional depalletizing system described above. The operation of the conventional depalletizing system will be described based on the flowchart shown in FIG. The work 5 stacked on the pallet 6 is depalletized by the following procedure.

(A) One work is recognized by a visual sensor to obtain the position (step S41). (A) One piece of work is depalletized by the robot 1 according to the position obtained in (a) (step S4).
2). (C) The steps (A) and (A) are repeated to perform depalletizing until there is no more than one step of the work (step S43). In order to depalletize all the works 5 on the pallet 6 according to the above procedure, this process is repeated for the number of stages of the works 5.

[0006]

In the conventional depalletizing system, all the workpieces 5 must be recognized by the visual sensor one by one as described above, and the positions must be obtained to depalletize them. It took a long time to recognize the work 5 of.

The present invention has been made to solve the above problems, and an object of the present invention is to obtain a depalletizing method capable of performing depalletizing while shortening the recognition time of a work.

[0008]

A depalletizing method according to the present invention includes a camera for displaying a work stacked on a pallet, a calculation unit for processing an image displayed by the camera to obtain a position of the work. In a depalletizing system equipped with a robot for depalletizing based on the position information of the work by the arithmetic unit, (a) the entire one stage of the work stacked on the pallet is recognized as one, and Procedure for obtaining position (b) From the positions of the vertices obtained in step (a),
Procedure for determining whether or not one work is aligned by calculating the length of the entire side of one work and the length of the diagonal line and comparing it with the value input in advance (c) One work is aligned If yes, then step (a)
The position of each work is de-palletized from the positions of the vertices obtained by the above and the data such as the size of the work input in advance, and the work is recognized one by one when the positions are not aligned. Is performed and depalletizing is performed according to the above steps (a) to (c).

[0009]

In the depalletizing method according to the present invention, the entire one stage of the work stacked on the pallet is recognized as one lump, and it is determined whether or not the work is aligned based on the length of the side and the diagonal line. However, if the workpieces are aligned, the position of each workpiece is calculated based on the pre-entered data, and if not aligned, the workpieces are recognized by the camera and the positions of the workpieces are calculated as in the conventional case. When recognizing and depalletizing, the position is recognized and the position is determined without taking time.

[0010]

【Example】

Example 1. FIG. 1 is a flow chart showing a depalletizing method according to an embodiment of the present invention and showing a procedure for recognizing a work 5 by the arithmetic unit 3 and a depalletizing procedure by the robot controller 2 in FIG. The procedure of this embodiment will be described based on this flowchart. In this embodiment, the work 5 on the pallet 6 is depalletized by the following procedure.

(A) All the works 5 corresponding to one stage of the work on the pallet 6 are recognized as one, and the four vertices are obtained by the arithmetic unit 3 (step S11).

(B) From the vertices obtained in step (a) by the computing unit 3, the side a or b of the rectangle shown in FIG. 3 and the diagonal line c
Calculates the length (step S12).

(C) In the arithmetic unit 3, the lengths of the sides and the diagonal lines obtained in the step (b) are compared with the values previously input to the memory in the arithmetic unit 3 (not shown), and the comparison difference between them is within a predetermined value. If it is, it is determined that one work is aligned, and if the comparison difference is equal to or more than a predetermined value, it is determined that the work 5 is disturbed (step S13).

(D) When the works are aligned, the position of each work is calculated from the position of the apex obtained in step (a) by the calculation unit 3 and the data such as the size of the work input in advance. Is calculated (step S14).

(E) Next, the calculation unit 3 performs the procedure (d).
The robot controller 2 depalletizes one work according to the position of the work obtained by the step S1.
5).

(F) The robot controller 2 repeats the procedure (e) until there is no work for one step (step S16).

(G) If the work is disturbed in step S13, the conventional recognition procedure is performed (steps S17 to S19). That is, step S1
7 to S19 are the same as steps S41 to S43 shown in FIG. 3, and depalletizing is performed as follows. (A) A single work is recognized by a visual sensor to obtain the position (step S41). (A) The robot 1 depalletizes one work according to the position obtained by the procedure (a) (step S4).
2). (C) The procedures (A) and (A) are repeated, and depalletizing is performed until there is no work for one step (step S43). In order to depalletize all the works 5 on the pallet 6 according to the above procedure, this process is repeated for the number of stages of the works 5.

Therefore, according to the above embodiment, the pallet 6
Recognize the entire work 5 for one step above as a block, find the positions of the four vertices, judge whether the work for one step is aligned, and if aligned, the entire four vertices. The position of each work is calculated and the position of each work is calculated as before when it is not aligned.Even when recognizing many works and depalletizing, it does not take time. It is possible to obtain the position by recognizing.

[0019]

As described above, according to the present invention, the position of the work is obtained by calculation if one stage of the work is recognized as a group and aligned, and if the work is disturbed, one by one is recognized. Since the position is calculated by using the above method, the recognition time is shortened as a whole, and the work can be recognized even if the work is disturbed.

[Brief description of drawings]

FIG. 1 is a flowchart showing a recognition procedure and a depalletizing procedure of a depalletizing system according to an embodiment of the present invention.

FIG. 2 is a configuration diagram showing a depalletizing system.

FIG. 3 is an explanatory diagram showing a field of view of a camera 4 of the visual sensor shown in FIG.

FIG. 4 is a flowchart showing a recognition procedure and a depalletizing procedure of a conventional depalletizing system.

[Explanation of symbols]

 1 robot 2 robot controller 3 computing unit 4 camera of visual sensor 5 work 6 pallet

Claims (1)

[Claims] 1. A camera for displaying a work stacked on a pallet, a calculation unit for processing an image displayed by this camera to obtain a position of the work, and depalletizing based on position information of the work by the calculation unit. In a depalletizing system equipped with a robot, (a) a step of recognizing the whole one stage of the work stacked on the pallet as one and determining the position of the vertex (b) by the step (a) From the obtained vertex position,
Procedure for determining whether or not one work is aligned by calculating the length of the entire side of one work and the length of the diagonal line and comparing it with the value input in advance (c) One work is aligned If yes, then step (a)
The position of each workpiece is de-palletized from the position of the vertices obtained by the above and the data such as the size of the workpiece input in advance and depalletizing is performed. And a depalletizing procedure for depalletizing the workpiece according to the above steps (a) to (c).