JP6904106B2 - Picking system - Google Patents

Description

The present invention relates to a picking system for picking articles from a group of articles composed of a plurality of stacked articles.

There is a picking system that picks articles one by one from the top by a picking robot for a group of articles composed of a plurality of stacked articles (for example, Patent Document 1).

In such a picking system, the picking robot holds the upper surface of the article by using a sensor that measures the distance from the picking robot to the upper surface of the article. Further, when releasing the article held by the picking robot, a sensor such as a photoelectric sensor for measuring the height of the article held is separately provided, and the height of the article held by the picking robot is set to the side. After measuring with a sensor from the side, the release height of the article is determined.

Japanese Unexamined Patent Publication No. 07-277512

As described above, the information regarding the height of the article held by the picking robot is necessary for releasing the article without dropping the article from a high place and without crushing the article.

However, the process of measuring the height of an article with a dedicated sensor is a factor that lowers the picking efficiency in the picking system. In addition, a place for arranging a dedicated sensor is required, which causes an increase in the size of the picking system.

The present invention has been made in view of the above problems, and relates to a picking system capable of acquiring the height of an article without using a dedicated sensor for measuring the height of the article.

In order to achieve the above object, the picking system, which is one of the present inventions, is a picking system for picking an article from a group of articles composed of a plurality of stacked articles, and the control device and the article group are moved upward. The control device includes a camera that captures images from the above, and a distance measuring means that measures a top surface distance, which is a distance from a reference height to the top surface of an article arranged at the top of the article group in the vertical direction. The height of the article group is calculated based on the step number calculation unit that calculates the number of steps, which is the number of articles per step of the article group, based on the image information acquired from the camera, and the upper surface distance acquired from the distance measuring means. The number of stages of the article group is calculated by dividing the number of stages calculated from the total number of articles acquired, the total number of articles acquisition unit for acquiring the total number of articles included in the article group, and the article group height calculation unit. By dividing the number of stages from the height of the article group obtained by the article group height calculation unit and the article group height calculation unit, the article height, which is the height per article included in the article group, is calculated. It is characterized by having an article height calculation unit.

As a result, the image from the upper surface of the article group, the measurement of the distance from the reference height above the article group to the upper surface of the article group, and the total number of articles in the article group normally possessed by the picking system can be obtained. Can be used to determine the height of one of the articles. Therefore, a dedicated sensor for measuring the height of the article and an extra operation for measuring the height are not required, and the picking ability can be improved. In addition, a sensor or the like that measures the height of the article from the side is not required, and the entire picking system can be miniaturized.

Further, a picking robot for picking an article from the article group is provided, and the article height calculation unit starts the operation of holding the first article of the article group by the picking robot until it is released. May be calculated.

As a result, since the height of the article held during the picking operation is calculated, the time required for the picking operation can be shortened and the picking efficiency can be improved.

Further, a picking robot for picking an article from the above-mentioned article group may be provided, and the picking robot may release an article held by the picking robot based on the acquired height of the article.

According to this, the picking robot can release the article without crushing the article without dropping the article from a high position, and damage to the article can be avoided.

Further, a picking robot for picking an article from the article group may be provided, and the picking robot may hold an article from the article group using the acquired article height.

According to this, when holding each article, it is not necessary to separately measure the height to the upper surface of the article for each article, and it is possible to improve the picking efficiency.

It should be noted that the implementation of the present invention also corresponds to the implementation of a program for causing a computer to execute each process included in the picking system. Of course, implementing a recording medium on which the program is recorded also corresponds to the implementation of the present invention.

According to the picking system of the present invention, information indicating the height of an article can be obtained without separately providing a dedicated sensor.

FIG. 1 is a perspective view showing a picking system. FIG. 2 is a block diagram showing each processing unit of the control device together with the mechanism unit. FIG. 3 is a flowchart showing the operation flow of the picking system.

Next, an embodiment of the picking system according to the present invention will be described with reference to the drawings. The following embodiments are merely examples of the picking system according to the present invention. Therefore, the present invention is defined by the wording of the claims with reference to the following embodiments, and is not limited to the following embodiments. Therefore, among the components in the following embodiments, the components not described in the independent claims indicating the highest level concept of the present invention are not necessarily necessary for achieving the object of the present invention, but more. Described as constituting a preferred form.

In addition, the drawings are schematic views in which emphasis, omission, and ratio are adjusted as appropriate to show the invention of the present application, and may differ from the actual shape, positional relationship, and ratio.

FIG. 1 is a perspective view showing a picking system.

As shown in the figure, the picking system 100 can automatically perform a picking operation of taking out at least one article 201 from an article group 200 composed of a plurality of stacked articles 201 and moving it to another place. The system includes a control device 101, a camera 102, a distance measuring means 103, and a picking robot 104.

The article 201 to be picked by the picking system 100 is not particularly limited, and examples thereof include pharmaceuticals, daily necessities, and foods contained in a package. The external shape of the article 201 is not particularly limited, but as shown in FIG. 1, a rectangular parallelepiped including a cube is often the target of picking. Further, an article group 200 is a state in which the articles 201 are arranged in a horizontal plane (XY plane in the drawing) and the arranged articles 201 are stacked in a plurality of stages in the vertical direction (Z-axis direction in the drawing). The arrangement of the articles 201 in the first stage of the article group 200 may be one row or a plurality of rows.

In order to stably stack the articles 201 in the vertical direction, the arrangement of the articles 201 in each stage is preferably the same, but if the number of articles 201 arranged in one stage is the same in each stage, the front, back, left and right. It may be arranged in such a way that the numbers are changed for each stage. In addition, the article group 200 may include a container, a packing material, or the like that accommodates the entire stacked articles 201 and has an open top. In this case, it is very difficult to measure the height of each article 201 from the side of the article group 200 before picking the article 201, and the picking system 100 of the present embodiment is particularly effective.

The camera 102 is a device that captures an image of the upper surface portion of the article group 200 in which the articles 201 are arranged and stacked from above the article group 200. The type of the camera 102 is not particularly limited, and for example, a digital camera capable of acquiring an image in the visible light region as an image signal can be shown. The camera 102 may be one capable of acquiring an image in an infrared region, a camera 102 capable of acquiring an image in an ultraviolet region, or the like.

In the case of the present embodiment, the image signal acquired by the camera 102 is also used as a signal for detecting the position and orientation of the article 201 to be picked by the picking robot 104.

The camera 102 may be arranged at a position where the article group 200 being transported to the picking position where the picking robot 104 is installed can be imaged, and the upper surface of the article group 200 may be imaged during the transportation.

The distance measuring means 103 is arranged above the article group 200, and is a vertical distance from a reference height set above the article group 200 to the upper surface of the article 201 arranged at the uppermost stage of the article group 200. It is a device that measures the distance. The distance measuring method of the distance measuring means 103 is not particularly limited, and examples thereof include those using laser light, those using light other than laser light, and those using ultrasonic waves.

In the case of the present embodiment, the reference height is the height at which the distance measuring means 103 is arranged. The distance measuring means 103 outputs the vertical distance from the upper surface of the article 201 arranged at the uppermost stage of the article group 200 to the distance measuring means 103 as the upper surface distance. Further, the top surface distance, which is the information output by the distance measuring means 103, is used for the operation of the picking robot 104 to hold the article 201.

The distance measuring means 103 is not only present at a position where the upper surface of the article group 200 arranged at a position where the camera 102 can take an image can be measured as in the present embodiment, but is also conveyed to the picking robot 104. It may be arranged at a position where the distance to the upper surface of the article group 200 in the middle can be measured, and the distance may be measured for the article group 200 in the middle of transportation.

The picking robot 104 is a robot capable of picking one or a plurality of articles 201 from the article group 200 at the same time. In the case of the present embodiment, the articulated robot is exemplified as the picking robot 104, but the picking robot 104 is not limited to this, and is configured by combining a parallel link robot and a plurality of linear motion mechanisms. It may be a robot or the like that does not have a joint.

FIG. 2 is a block diagram showing each processing unit of the control device together with the mechanism unit.

As shown in the figure, the control device 101 calculates the height of the article 201 based on the image information acquired from the camera 102, the top surface distance acquired from the distance measuring means 103, and the total number acquired from the host controller or the like. It is an apparatus, and includes a stage number calculation unit 121, an article group height calculation unit 131, a total number acquisition unit 111, a stage number calculation unit 112, and an article height calculation unit 113.

Specifically, for example, the control device 101 is a device that executes each process by operating the processor according to an instruction included in a computer program stored in the storage device, and a hardware circuit that executes each process. It is a device equipped with at least one. Further, the hardware circuit is a circuit including at least one of a digital circuit and an analog circuit.

The stage number calculation unit 121 acquires image information in which the entire upper surface of the article group 200 imaged by the camera 102 is captured, and based on the acquired image information, determines the number of stages, which is the number of articles per stage of the article group 200. It is a processing unit to calculate. The calculation method for calculating the number of steps of the step number calculation unit 121 is not particularly limited, but for example, the image information acquired from the camera 102 is subjected to image processing to recognize the area of the upper surface of the article 201 and to recognize the area of the upper surface of the article 201. It may be obtained by recognizing the area of the upper surface of the article group 200 and dividing the area of the upper surface of the article 201 from the area of the upper surface of the article group 200. Further, the image information acquired from the camera 102 may be subjected to image processing to recognize the boundary line of the adjacent article 201, and the number of steps may be counted from the number of boundary lines.

The article group height calculation unit 131 calculates the height of the article group 200 based on the upper surface distance, which is the distance from the reference height obtained from the distance measuring means 103 to the upper surface of the article 201 arranged at the uppermost stage of the article group 200. It is a processing unit to be processed.

In the case of the present embodiment, as an initial setting, the article group height calculation unit 131 measures the distance from the mounting surface, which is the surface on which the article group 200 is mounted, in the state where the article group 200 is not mounted. The distance to the distance is acquired in advance by the distance measuring means 103, and the obtained information is held as a reference height. Then, the height of the article group 200 is calculated by subtracting the upper surface distance, which is the distance to the upper surface of the article group 200 acquired by the distance measuring means 103, from the holding reference height.

Further, when the article group 200 is placed on a pallet or is housed in a container, a packing material, or the like, the article group height calculation unit 131 determines the thickness of the pallet existing below the article group 200 and the thickness of the pallet. The height of the article group 200 is calculated by subtracting the thickness of the container, the packing material, and the like. Information on these thicknesses may be acquired in advance and held by the article group height calculation unit 131, or may be acquired from a host controller or the like.

The total number acquisition unit 111 is a processing unit that acquires the total number of articles 201 included in the article group 200 from a host controller or the like based on communication or the like. Here, the host controller is a controller that outputs order information such as the number of articles 201 to be picked from the article group 200 to the picking system 100, for example. Further, the host controller may output order information or the like to a plurality of picking systems 100.

The stage number calculation unit 112 is a processing unit that calculates the number of stages of the article group 200 by dividing the number of stages calculated by the stage number calculation unit 121 from the acquired total number. In the case of this embodiment, the number of stages calculation unit 112 outputs a natural number as the number of stages by rounding up after the decimal point.

The article height calculation unit 113 divides the number of steps calculated by the step number calculation unit 112 from the height of the article group 200 obtained by the article group height calculation unit 131, thereby dividing the height per article included in the article group 200. It is a processing unit that calculates the height of the article. In the case of the present embodiment, the article height calculation unit 113 includes a communication means for outputting the article height as information to the picking robot 104 or the like.

Next, the operation of the picking system 100 will be described.

FIG. 3 is a flowchart showing the operation flow of the picking system.

First, the article group 200 is carried into the picking position (S101). The carry-in method is not particularly limited, but for example, the article group 200 is carried to the picking position by being carried by a conveyor or the like. Further, the packing style of the article group 200 to be carried in is, for example, when the articles 201 are stacked on the pallet, or the articles 201 in the stacked state are housed in a case, a box for packing, or the like. Can show the condition.

With the article group 200 arranged at the picking position, the camera 102 takes an image of the entire article 201 arranged at the top of the article group 200 (S102).

Further, the distance measuring means 103 measures the distance to the upper surface of the article 201 arranged at the uppermost stage of the article group 200 (S013).

The imaging step (S102) by the camera 102 and the distance measuring step (S103) by the distance measuring means 103 are performed substantially at the same time. Further, the order of the imaging process by the camera 102 and the distance measuring process by the distance measuring means 103 is not limited.

At this stage, the picking robot 104 starts an operation for holding the first article 201 from the article group 200 (S104).

In parallel with the picking robot 104 starting the picking operation, the stage number calculation unit 121 calculates the stage number from the image information acquired by the camera 102 (S105).

Further, in parallel with the calculation of the number of steps, the article group height calculation unit 131 calculates the height of the article group 200 based on the upper surface distance acquired from the distance measuring means 103 (S106).

Further, in parallel with the calculation of the height of the article group 200, the total number acquisition unit 111 acquires the total number from the host controller or the like (S107). The timing of acquiring the total number is not limited to this, and may be acquired, for example, while the article group 200 is being carried into the picking position.

The stage number calculation unit 112 calculates the number of stages in which the articles 201 are stacked in the article group 200 based on the total number acquired from the total number acquisition unit 111 and the stage number calculated by the stage number calculation unit 121 (S108).

After the number of steps is calculated, the article height calculation unit 113 calculates the article height, which is the height per article, based on the height of the article group 200 and the number of steps (S109). Further, the article height calculation unit 113 outputs the article height to the picking robot 104.

The picking robot 104 releases the article held based on the article height acquired from the article height calculation unit 113 at a predetermined position and height (S110).

As described above, a series of operations for picking the first article 201 after the article group 200 is brought into the picking position is completed.

By this operation, at least the article height calculation unit 113 can calculate the article height from the start of the operation of holding the first article 201 from the article group 200 by the picking robot 104 to the release, and the picking robot 104. Can safely release the article 201 without the time loss of separately measuring the article height.

Further, the step of measuring the height of the article 201 held by the picking robot 104 with a sensor or the like separately installed can be omitted, and the efficiency of the picking work can be improved. In addition, the entire picking system 100 can be miniaturized to save space.

When the picking robot 104 continuously picks the article 201 from the same article group 200, the next article 201 from the article group 200 can be held by using the calculated article height.

As a result, the picking robot 104 can efficiently hold the article 201 even for the article 201 arranged in the next stage.

The invention of the present application is not limited to the above-described embodiment. For example, another embodiment realized by arbitrarily combining the components described in the present specification and excluding some of the components may be the embodiment of the present invention. In addition, the present invention also includes modifications obtained by making various modifications that can be conceived by those skilled in the art within the scope of the gist of the present invention, that is, the meaning indicated by the wording described in the claims, with respect to the above-described embodiment. Is done.

For example, in the above embodiment, the camera 102 and the distance measuring means 103 have been described as separate devices, but a three-dimensional sensor such as a TOF (Time of Flight) camera, an LRF (Laser Range Finder), or a stereo camera is used. The upper surface of the article group 200 may be imaged by one device, and the distance from the reference height to the upper surface of the article group 200 may be measured.

Further, the distance measuring means 103 may be attached to the tip of an arm of the picking robot 104 or the like, and may measure the distance between the picking robot 104 and the article 201 when the picking robot 104 holds the article 201. In this case, the reference height fluctuates according to the operation of the picking robot 104.

Further, the operation of each processing unit of the control device 101 is not limited to the above-described embodiment, and may proceed at the same time, and the processing may be back and forth.

Further, although the control device 101 has been described as an integrated device, the control device 101 may be a combination of a plurality of devices. For example, the distance measuring means 103 may include the article group height calculating unit 131, and the article height calculating unit 113 may acquire information indicating the height of the article group 200 from the distance measuring means 103.

Further, the total number acquisition unit 111 may acquire the total number of articles 201 included in the article group 200 not from the host controller but from the controller that manages the inventory connected in the same row as the picking system 100. It may be acquired by providing a device for storing the total number in 100.

100 Picking system 101 Control device 102 Camera 103 Distance measuring means 104 Picking robot 111 Total number acquisition unit 112 Number of stages calculation unit 113 Article height calculation unit 121 Number of stages calculation unit 131 Article group height calculation unit 200 Article group 201 Articles

Claims (3)

A picking system that picks articles from a group of articles consisting of a plurality of stacked articles.
Control device and
A camera that captures the group of articles from above,
A distance measuring means for measuring the upper surface distance, which is the distance from the reference height to the upper surface of the article arranged at the uppermost stage of the article group in the vertical direction, is provided.
The control device is
A stage number calculation unit that calculates the number of stages, which is the number of articles per stage of the article group, based on the image information acquired from the camera.
An article group height calculation unit that calculates the height of the article group based on the top surface distance obtained from the distance measuring means, and
A total number acquisition unit for acquiring the total number of articles included in the article group, and
The number of stages calculation unit that calculates the number of stages of the article group by dividing the number of stages calculated from the total number of acquired items.
An article height calculation unit that calculates the article height, which is the height of each article included in the article group, by dividing the number of steps from the height of the article group obtained by the article group height calculation unit. ,
A picking robot that picks an article from the article group is provided.
The article height calculation unit
A picking system that calculates the height of an article from the start of the operation of holding the first article from the group of articles by the picking robot to the release of the article. The picking robot
The picking system according to claim 1, wherein the height at which the article held by the picking robot is released is set based on the acquired article height. The picking robot
The picking system according to claim 1 or 2 , wherein an article is held from the article group by using the acquired article height.

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