WO2023037647A1 - Robot hand and picking system - Google Patents

Abstract

This robot hand is provided with a holding unit, a holding drive unit, and a drive power transmission mechanism which movably supports the holding unit and which transmits drive power from the holding drive unit to the holding unit. Further, this drive power transmission mechanism has multiple links and causes the holding surface contacting the article in the holding unit to always move in the same orientation.

Description

Robot hand and picking system

The present invention relates to a robot hand and a picking system equipped with this robot hand.

In recent years, there has been known a picking system in which a transport robot holds an article brought in from a process upstream of a predetermined place and carries it out to a predetermined place. Further, the carry-out robot is provided with a robot hand for gripping the article.

For example, Patent Document 1 describes a technology related to a robot hand that grips an object. Patent Document 1 describes a technique including a fingertip link, a base link, a multiple bar finger link mechanism, and an actuator connected to the base link and rotating the multiple bar finger link mechanism around the base link. there is

Japanese Patent Publication No. 2018-507116

However, in the technique described in Patent Document 1, the two fingertip links are rotatably supported by the base link, and the base link is rotated, so that the force is sufficiently transmitted to the tip of the fingertip link. I wasn't able to. Therefore, with the technique described in Patent Document 1, there is a possibility that the grasped article may fall out of the robot hand when being conveyed.

In consideration of the above problems, the present purpose is to provide a robot hand and a picking system that can reliably grip articles.

In order to solve the above problems and achieve the object, a robot hand includes a gripping section for gripping an article, a gripping driving section for driving the gripping section, a gripping section for movably supporting the gripping section, and a driving force from the gripping driving section. and a driving force transmission mechanism for transmitting to the grip portion. The driving force transmission mechanism has a plurality of links, and always moves the gripping surface of the gripping portion that contacts the article in the same posture.

The picking system also includes a transport robot that transports articles and a robot hand provided on the transport robot. Further, the robot hand described above is used as the robot hand.

According to the robot hand and picking system configured as described above, it is possible to reliably grasp an article.

1 is a schematic configuration diagram showing a picking system according to an embodiment; FIG. 1 is a front view showing a robot hand according to an embodiment; FIG. FIG. 4 is a front view showing a state in which the grasping portion of the robot hand according to the embodiment is opened; FIG. 4 is a front view showing a state in which the telescopic mechanism of the robot hand according to the embodiment is extended; FIG. 3 is a perspective view showing a grasping portion of the robot hand according to the embodiment; FIG. 11 is a front view showing an example of gripping a bottle-shaped article with the gripping portion of the robot hand according to the embodiment; FIG. 10 is a top view showing an example of gripping a bottle-shaped article with the gripping portion of the robot hand according to the embodiment; FIG. 7 is a front view showing an example of gripping articles arranged side by side by the gripping portion of the robot hand according to the embodiment; FIG. 7 is a front view showing an example of gripping an article having a small width with the gripping portion of the robot hand according to the embodiment; FIG. 7 is a front view showing an example of gripping a wide article with the gripping portion of the robot hand according to the embodiment; 11A to 11D are explanatory diagrams showing the picking operation in the first control mode in the picking system and the robot hand according to the embodiment. 12A to 12C are explanatory diagrams showing the picking operation in the second control mode in the picking system and the robot hand according to the embodiment. 13A to 13C are explanatory diagrams showing the picking operation in the third control mode in the picking system and the robot hand according to the embodiment.

Embodiments of the robot hand and picking system will be described below with reference to FIGS. 1 to 13. FIG. In addition, the same code|symbol is attached|subjected to the member which is common in each figure.

1. Embodiment 1-1. Configuration Example of Picking System First, the configuration of a picking system according to an embodiment (hereinafter referred to as "this example") will be described with reference to FIG.
FIG. 1 is a schematic configuration diagram showing the picking system of this example.

As shown in FIG. 1, the picking system 50 includes a transport robot 51, a carry-in conveyor 52 that carries the article 100 into the transport robot 51, a moving mechanism 53, an imaging device 55, and a carry-out conveyor 54. The picking system 50 uses the transport robot 51 to transport the article 100 in the storage cardboard 200 transported by the loading conveyor 52 to the loading container 56 on the loading conveyor 54 . The picking system 50 also has a control device 57 that controls the transfer robot 51 , the carry-in conveyor 52 , the moving mechanism 53 , the imaging device 55 , and an information storage device 58 . The information storage device 58 is connected to the control device 57 . The information storage device 58 stores information about the article 100 such as the shape and size of the article 100 to be handled and the posture of the article 100 placed on the carry-in conveyor 52 .

The transport robot 51 is, for example, a vertical articulated robot with 6-axis joints. An arm of the transport robot 51 is provided with a robot hand 1 that sucks and grips an article 100 . Details of the robot hand 1 will be described later.

The imaging device 55 is arranged above the position where the transport robot 51 grips the article 100 using the robot hand 1 . The imaging device 55 photographs the article 100 carried in from the carry-in conveyor 52 . Then, the imaging device 55 outputs the captured information to the control device 57 . The control device 57 determines information about the article 100 such as the position of the article 100 and the size of the article 100 based on the information acquired from the imaging device 55 . The control device 57 controls the operations of the transport robot 51 and the robot hand 1 based on the information regarding the article 100 .

In the picking system 50 of this example, an example in which the imaging device 55 is provided above the position where the article 100 is gripped has been described, but the present invention is not limited to this. For example, the imaging device 55 may be provided in the transport robot 51 or the robot hand 1, or may be arranged on the side of the position where the article 100 is gripped.

Further, an example has been described in which the control device 57 determines the size, type, etc. of the article 100 based on the information captured by the imaging device 55, but the present invention is not limited to this. For example, information on the size, type, etc. of the article 100 may be stored in the information storage device 58 in advance, and the control device 57 may acquire information on the article 100 from the information storage device 58 .

The transport robot 51 is supported by a moving mechanism 53 so as to be movable in one axial direction. The moving mechanism 53 is arranged between the carry-in conveyor 52 and the carry-out conveyor 54 . An input conveyor 52 is arranged on one side of the moving mechanism 53 in the moving direction, and an unloading conveyor 54 is arranged on the other side of the moving mechanism 53 in the moving direction.

The carry-in conveyor 52 conveys the storage cardboard 200 containing a plurality of articles 100 from the upstream process of the picking system 50 to a predetermined position. The carry-out container 56 provided on the carry-out conveyor 54 stores the articles 100 carried out by the transport robot 51 and the robot hand 1 . Then, the unloading conveyor 54 conveys the unloading container 56 containing the articles 100 to a predetermined position in the downstream process of the picking system 50 .

Although an example in which the transport robot 51 is moved by the moving mechanism 53 has been described, the present invention is not limited to this, and the transport robot 51 itself may be provided with a moving mechanism, or the transport robot 51 may be fixed. .

Although an example of storing the articles 100 in the carry-out container 56 has been described as the picking system 50, the picking system 50 is not limited to this. As the picking system 50, for example, the article 100 gripped by the robot hand 1 of the transfer robot 51 may be transferred onto the unloading conveyor 54, or may be stored in a storage shelf (not shown). shall apply.

Also, an example in which a vertically articulated robot having 6-axis joints is applied as the transport robot 51 has been described, but it is not limited to this. As the transport robot 51, a two-axis robot that rotates in the horizontal direction and moves in the vertical direction may be applied, and other various robots can be applied.

1-2. Configuration Example of Robot Hand Next, the detailed configuration of the robot hand 1 provided in the transport robot 51 will be described with reference to FIGS. 2 to 4. FIG.
FIG. 2 is a front view showing the robot hand 1. FIG. FIG. 3 is a front view showing a state in which a grasping portion of the robot hand 1 described later is opened, and FIG. 4 is a front view showing a state in which an expansion mechanism of the robot hand 1 described later is extended.

As shown in FIGS. 2 to 4, the robot hand 1 includes a body portion 2 attached to a transport robot 51, an adsorption portion 3 that adsorbs an article 100, an expansion mechanism 4, a first gripping portion 5A, a second It has a gripping portion 5B and a gripping driving portion 7 . The robot hand 1 also has a first driving force transmission mechanism 20A and a second driving force transmission mechanism 20B.

The body part 2 is composed of a substantially T-shaped member. The main body 2 has a base 2a attached to the transport robot 51 and a support 2b provided at the tip of the base 2a. The base portion 2a is connected to the intermediate portion of the support portion 2b. An extension mechanism 4 is installed in the main body portion 2 .

A linear actuator, for example, is applied as the telescopic mechanism 4 . The expansion mechanism 4 expands and contracts along the longitudinal direction, which is the direction in which the base portion 2a of the body portion 2 extends, and protrudes from the intermediate portion of the support portion 2b of the body portion 2 in the direction opposite to the base portion 2a. . A suction unit 3 is installed at the tip of the extension mechanism 4 . And the extension mechanism 4 supports the adsorption|suction part 3 so that extension is possible.

The adsorption part 3 is formed in a bellows shape from a member having flexibility. A negative pressure generator (not shown) is connected to the suction unit 3 . When the adsorption unit 3 contacts the article 100 and the negative pressure generating device is driven, the adsorption section 3 adsorbs the article 100 as shown in FIG. 11 .

In addition, a swing shaft may be provided at a location where the adsorption section 3 is installed in the extension mechanism 4 . Then, the adsorption portion 3 may be oscillated around the oscillating axis.

Although an example in which a linear actuator driven by pneumatic pressure or electric power, for example, is applied to the telescopic mechanism 4, other various telescopic mechanisms such as gears, motors, and cylinders may be applied as long as similar effects can be obtained. Further, the expansion mechanism 4 is restricted in its rotation by a guide mechanism (not shown) so that it does not rotate about the expansion and contraction shaft, so that the adsorption section 3 does not rotate.

Also, in this example, an example in which the expansion mechanism 4 for expanding and contracting the adsorption portion 3 is provided has been described, but the expansion mechanism 4 may not be provided.

[Grip drive unit/driving force transmission mechanism]
Next, the configurations of the grip drive unit 7, the first driving force transmission mechanism 20A, and the second driving force transmission mechanism 20B will be described.
A grip drive unit 7 is installed at one end of the support portion 2b. The grip drive unit 7 is, for example, a motor with a speed reducer. A drive shaft of the grip drive unit 7 is provided with a main driving force transmission unit 8A. The main driving force transmission portion 8A is configured by, for example, a gear. The main driving force transmission portion 8A meshes with a first driving force transmission portion 8B, which will be described later, and transmits the driving force of the grip driving portion 7 to the first driving force transmission portion 8B.

The first driving force transmission mechanism 20A is arranged on one end side of the support portion 2b, and the second driving force transmission mechanism 20B is arranged on the other end portion side of the support portion 2b. The adsorption portion 3 is arranged between the first driving force transmission mechanism 20A and the second driving force transmission mechanism 20B. The first driving force transmission mechanism 20A is provided with a first gripping portion 5A, and the second driving force transmission mechanism 20B is provided with a second gripping portion 5B. The first gripping portion 5A and the second gripping portion 5B are supported by the first driving force transmission mechanism 20A and the second driving force transmission mechanism 20B and arranged to face each other.

The first driving force transmission mechanism 20A has a first link 6A, a second link 6C, a third link 6B, and a first driving force transmission portion 8B. The first driving force transmission portion 8B is rotatably supported by one end portion of the support portion 2b. The first driving force transmission portion 8B is composed of a gear, like the main driving force transmission portion 8A. The first driving force transmission portion 8B meshes with the main driving force transmission portion 8A and a second driving force transmission portion 8C, which will be described later.

A link node 9A, which is one end of the first link 6A, is fixed to the first driving force transmission portion 8B. As the first driving force transmission portion 8B rotates, the first link 6A swings around the link node 9A.

A link node 9D, which is one end of the second link 6C, is rotatably supported by one end of the support portion 2b. The first link 6A and the second link 6C are arranged parallel to each other. A link node 9B, which is the other end of the first link 6A, and a link node 9C, which is the other end of the second link 6C, are rotatably connected to the third link 6B. A first grip portion 5A is provided on the third link 6B. When the first driving force transmission portion 8B rotates, the quadrangle connecting the link nodes 9A, 9B, 9C, and 9D swings while maintaining a parallelogram, and the first gripping portion 5A provided on the third link 6B moves. do.

Like the first driving force transmission mechanism 20A, the second driving force transmission mechanism 20B has a first link 6D, a second link 6F, a third link 6E, and a second driving force transmission portion 8C. there is The second driving force transmission portion 8C is rotatably supported by the other end portion of the support portion 2b. The second driving force transmission portion 8C is composed of gears, like the main driving force transmission portion 8A and the first driving force transmission portion 8B. The second driving force transmission portion 8C meshes with the first driving force transmission portion 8B, and rotates together with the rotation of the first driving force transmission portion 8B. Although an example in which the main driving force transmission portion 8A, the first driving force transmission portion 8B, and the second driving force transmission portion 8C are configured by gears has been described, the present invention is not limited to this. For example, other various transmission mechanisms such as pulleys and belts or chains may be applied.

A link joint 9E, which is one end of the first link 6D, is fixed to the second driving force transmission section 8C. As the second driving force transmission portion 8C rotates, the first link 6D swings around the link node 9E.

A link node 9H, which is one end of the second link 6F, is rotatably supported on the other end side of the support portion 2b. The first link 6D and the second link 6F are arranged parallel to each other. A link node 9F, which is the other end of the first link 6D, and a link node 9G, which is the other end of the second link 6F, are rotatably connected to the third link 6E. A second grip portion 5B is provided on the third link 6E. When the second driving force transmission portion 8C rotates, the quadrangle connecting the link nodes 9E, 9F, 9G, and 9H swings while maintaining a parallelogram, and the second gripping portion 5B provided on the third link 6E moves. do.

In the example shown in FIG. 2, when the first driving force transmission portion 8B rotates clockwise, the second driving force transmission portion 8C rotates counterclockwise. Therefore, the first gripping portion 5A and the second gripping portion 5B move toward each other. Then, the first gripping portion 5A and the second gripping portion 5B are closed.

On the other hand, when the first driving force transmission portion 8B rotates counterclockwise, the second driving force transmission portion 8C rotates clockwise. Therefore, the first gripping portion 5A and the second gripping portion 5B move away from each other as shown in FIG. Then, the first gripping portion 5A and the second gripping portion 5B are opened. As described above, according to the robot hand 1 of the present embodiment, the first gripping portion 5A and the second gripping portion are driven by the first driving force transmission mechanism 20A and the second driving force transmission mechanism 20B by driving the gripping driving portion 7. 5B opens and closes. The first driving force transmission portion 8B and the second driving force transmission portion 8C are configured by gears having the same number of teeth so that the first gripping portion 5A and the second gripping portion 5B open and close at the same speed. .

Note that the first gripping portion 5A and the second gripping portion 5B of this example are movably supported by a first driving force transmission mechanism 20A and a second driving force transmission mechanism 20B, which are parallel links. Therefore, gripping contact portions 11A and 11B, which are surfaces of the first gripping portion 5A and the second gripping portion 5B facing each other, move parallel to each other. That is, the driving force transmission mechanisms 20A and 20B move the gripping portions 5A and 5B while keeping the gripping contact portions 11A and 11B, which are the gripping surfaces of the gripping portions 5A and 5B, in the same posture. Thereby, the gripping contact portions 11A and 11B can be pressed against the article 100 from a substantially vertical direction.

Also, the link nodes 9A, 9E of the first links 6A, 6D that constitute the driving force transmission mechanisms 20A, 20B are directly connected to the first driving force transmission portion 8B or the second driving force transmission portion 8C. Thereby, the driving force from the grip driving portion 7 can be directly transmitted to the first links 6A and 6D via the first driving force transmitting portion 8B and the second driving force transmitting portion 8C. As a result, the driving force from the gripping driving portion 7 can be reliably transmitted to the first gripping portion 5A and the second gripping portion 5B, and the force for sufficiently gripping the article 100 can be ensured.

It should be noted that the reduction ratio of the motor with a speed reducer, which is an example of the grip drive section 7, is sufficiently larger than the reduction ratios of the main driving force transmission section 8A and the first driving force transmission section 8B. As a result, the dimensions of the main driving force transmission portion 8A, the first driving force transmission portion 8B and the second driving force transmission portion 8C can be reduced.

Here, as shown in FIGS. 2 and 3, the lower end of the suction portion 3 is positioned above the first gripping portion 5A and the second gripping portion 5B when the telescopic mechanism 4 is contracted. Thereby, as shown in FIG. 2, when closing the first gripping portion 5A and the second gripping portion 5B, it is possible to prevent the first gripping portion 5A and the second gripping portion 5B from coming into contact with the suction portion 3. . If it is known in advance that the article 100 to be handled has a thickness equal to or greater than the width of the suction surface of the suction portion 3, it is not necessary to close the gripping portions 5A and 5B as shown in FIG. Therefore, since the gripping portions 5A and 5B may be opened wider than the suction portion 3, the lower end of the suction portion 3 does not have to be above the gripping portions 5A and 5B when the telescopic mechanism 4 is contracted.

Further, as shown in FIG. 4, when the telescopic mechanism 4 is extended, the lower end of the suction portion 3 protrudes downward from the lower ends of the gripping portions 5A and 5B. As a result, the gripping portions 5A and 5B do not interfere with the suction of the article 100 by the suction portion 3 . When extending the telescopic mechanism 4, the gripping portions 5A and 5B are opened wider than the adsorption portion 3 as shown in FIG.

[Grip part]
Next, detailed configurations of the first gripping portion 5A and the second gripping portion 5B will be described with reference to FIG.
FIG. 5 is a perspective view showing grips 5A and 5B. The first gripping portion 5A and the second gripping portion 5B have the same configuration.
As shown in FIG. 5, the first grip portion 5A has a base 10A and a grip contact portion 11A. Similarly, the second gripping portion 5B has a base 10B and a gripping contact portion 11B.
In addition, since the first gripping portion 5A and the second gripping portion 5B have the same configuration, the first gripping portion 5A will be described in the following description.

The base 10A is formed in a substantially L shape. The base 10A has a first surface portion 10a and a second surface portion 10b. The first surface portion 10a and the second surface portion 10b are each formed in a substantially flat plate shape. The first surface portion 10a is fixed to the third links 6B, 6E of the driving force transmission mechanisms 20A, 20B. A second surface portion 10b is provided at a substantially right angle from an end portion of the first surface portion 10a. When the gripping portions 5A and 5B are attached to the driving force transmission mechanisms 20A and 20B, the second surface portion 10b of the first gripping portion 5A and the second surface portion 10b of the second gripping portion 5B face each other. A gripping contact portion 11A is fixed to the second surface portion 10b.

The gripping contact portion 11A is a substantially flat member. The gripping contact portion 11A has elasticity and is deformed by an external force. The gripping contact portion 11A is formed of a member having a surface with a relatively high coefficient of friction. For example, the gripping contact portion 11A may be made of rubber or the like. When gripping the article 100 , the gripping contact portion 11A contacts the article 100 . At this time, the gripping contact portion 11A is elastically deformed, and the article 100 can be stably gripped by the frictional force of the gripping contact portion 11A. Furthermore, the article 100 can be prevented from being damaged due to the elastic deformation of the gripping contact portion 11A.

Furthermore, a plurality of (four in this example) protrusions 11C are provided on the surface of the gripping contact portion 11A that contacts the article 100 . 11 C of protrusions are provided in the four corners of the surface of 11 A of holding contact parts. 11 C of protrusions are formed in substantially hemispherical shape. The shape of the protrusion 11C is not limited to a hemispherical shape, and may be conical, pyramidal, columnar, or any other shape. Furthermore, the number of projections 11C is not limited to four, and may be three or less, or five or more. Further, the positions where the projections 11C are arranged are not limited to the four corners of the gripping contact portion 11A, and can be arranged at various other positions.

6 and 7 are diagrams showing an example of gripping a bottle-shaped article 101, where FIG. 6 is a front view and FIG. 7 is a top view.
As shown in FIGS. 6 and 7 , the first gripping portion 5A and the second gripping portion 5B sandwich both sides of the mouth portion, which is the tip portion of the article 101 . At this time, as shown in FIG. 7, the plurality of projections 11C provided on the gripping contact portions 11A and 11B are positioned so as to surround the mouth portion of the article 101. As shown in FIG. Then, as shown in FIG. 6, of the plurality of projections 11C provided on the gripping contact portions 11A and 11B, the projection 11C located on the lower side in the vertical direction is caught in the opening of the article 101. As shown in FIG. By providing the protrusion 11C in this way, even when the bottle-shaped article 101 is to be gripped, it can be securely gripped. In addition, it is preferable to set the size of the projection 11C and the interval between the adjacent projections 11C according to the size of the article to be gripped.

An example of gripping an article 101 in which a plurality of articles 101 are arranged will be described with reference to FIG. FIG. 8 is a front view showing an example in which articles 101 arranged side by side are gripped by gripping portions 5A and 5B.
As shown in FIG. 8, when gripping an article 101 in which a plurality of articles 101 are arranged side by side, it is necessary to prevent the gripping portions 5A and 5B from interfering with adjacent articles 101. FIG. On the other hand, as described above, the bases 10A and 10B constituting the gripping portions 5A and 5B are formed in a substantially L shape, and the portions where the gripping contact portions 11A and 11B are provided are formed in a flat plate shape. It is Thereby, the grasping portions 5A and 5B can be inserted between the articles 101 without interfering with the adjacent articles 101. As shown in FIG. As a result, even when a plurality of articles 101 are arranged side by side, the articles 101 can be reliably gripped.

In order to insert the gripping portions 5A and 5B between the articles 101 and 101, the thickness of the gripping contact portions 11A and 11B and the second surface portions 10b of the bases 10A and 10B should be It is set sufficiently thinner than

In this example, an example in which the bases 10A and 10B are formed in a substantially L shape has been described, but the bases 10A and 10B are not limited to this, and may be formed in various other shapes such as a triangular shape and a square shape. .
However, as described above, it is preferable to form the bases 10A and 10B in a substantially L shape in order to grip the article 101 in which a plurality of articles 101 are arranged side by side.

An example of gripping an article 102 having a small width will be described with reference to FIG. FIG. 9 is a front view showing an example in which an article 102 having a small width is gripped by gripping portions 5A and 5B.
The article 102 shown in FIG. 9 has a tapered shape toward the tip, and the width of the tip is reduced. Here, as described above, the gripping portions 5A and 5B are movably supported by the driving force transmission mechanisms 20A and 20B each composed of a plurality of links. do. Therefore, as shown in FIG. 9, the surfaces of the gripping contact portions 11A and 11B can be brought into contact with the article 102 in the vertical direction. Then, the protrusions 11C provided on the gripping contact portions 11A and 11B can be brought into contact with the article 102 reliably.

As described above, when the telescopic mechanism 4 is contracted, the lower end of the suction portion 3 is positioned above the first gripping portion 5A and the second gripping portion 5B (see FIGS. 2 and 3). As a result, even if the gripping portions 5A and 5B are closed to a position where the gripping contact portions 11A and 11B of the gripping portions 5A and 5B are in contact with each other, the suction portion 3 does not interfere with the first gripping portion 5A and the second gripping portion 5B. do not have. As a result, even an article 102 having a small width as shown in FIG. 9 can be reliably gripped by the first gripping portion 5A and the second gripping portion 5B.

An example of gripping an article 100 having a large width will be described with reference to FIG. FIG. 10 is a front view showing an example in which an article 100 having a large width is gripped by gripping portions 5A and 5B.
As shown in FIG. 10, even with an article 100 having a large width, the surfaces of the gripping contact portions 11A and 11B can be brought into contact with the article 102 in the vertical direction. As shown in FIG. 10, when it is known in advance that the width of the article 100 is equal to or greater than the width of the suction surface of the suction portion 3, the gripping portions 5A and 5B are closed as shown in FIG. No need. Therefore, the lower end of the suction portion 3 does not have to be above the holding portions 5A and 5B when the expansion mechanism 4 is contracted.

As shown in FIGS. 6 to 10 described above, according to the robot hand 1 of this example, the gripping surfaces of the gripping portions 5A and 5B, which are the gripping surfaces of the gripping portions 5A and 5B, can grip objects 100, 101, and 102 of various shapes and sizes. The contact portions 11A and 11B can be brought into contact with the articles 100, 101 and 102 reliably.
Thereby, the articles 100, 101 and 102 can be reliably gripped by the gripping portions 5A and 5B.

Furthermore, the link joint 9A of the first link 6A among the plurality of links constituting the driving force transmission mechanisms 20A and 20B is connected to the first driving force transmission portion 8B to which the driving force from the grip driving portion 7 is transmitted. there is A link node 9E of the first link 6D is connected to a second driving force transmission portion 8C to which the driving force of the first driving force transmission portion 8B is transmitted. As a result, the driving force from the gripping driving portion 7 can be transmitted to the gripping contact portions 11A and 11B of the first gripping portion 5A and the second gripping portion 5B, and the force for sufficiently gripping the articles 100, 101, and 102 can be obtained. can be secured.

Next, a method of controlling the grip drive unit 7 will be described. Articles handled by the picking system 50 have various degrees of hardness, and there are articles that should not be crushed by the gripping portions 5A and 5B. For this reason, the robot hand 1 of this example controls the gripping drive section 7 so as to change the gripping force of the gripping sections 5A and 5B according to the article.

The torque of the gripping drive unit 7 is limited so that the gripping force of the article by the gripping units 5A and 5B is a predetermined value (gripping force) F. Then, the grip drive unit 7 stops when this torque limit is exceeded. It should be noted that the predetermined gripping force F is determined in advance according to the articles to be handled by the picking system 50 . The determination of the article is performed in the control device 57 based on the information of the article photographed by the imaging device 55 and the information of the article 100 stored in the information storage device 58 .

The control device 57 continues to drive the grip drive unit 7 up to a predetermined grip force F when driving the grip drive unit 7 . Then, the control device 57 stops the gripping driving section 7 when the reaction force from the article reaches the gripping force F. FIG. Further, since the gripping portions 5A and 5B and the gripping driving portion 7 are connected via the driving force transmission mechanisms 20A and 20B, the reaction force from the article generated in the gripping portions 5A and 5B is transferred to the gripping driving portion 7 as a driving force. It can be transmitted via the transmission mechanisms 20A, 20B. By controlling the grip drive unit 7 in this manner, the article can be reliably gripped with a predetermined gripping force F regardless of the width of the article. That is, there is no need to control the drive of the gripping driving section 7 according to the width dimension of the article, and the control of the gripping driving section 7 by the control device 57 can be easily performed.

Furthermore, the article can be gripped with an appropriate gripping force F without complicated control such as feedback control in which pressure sensors are provided in the gripping contact portions 11A and 11B of the gripping portions 5A and 5B. This makes it possible to easily control the grip drive unit 7 .

In the robot hand 1 of this example, an example in which two gripping portions 5A and 5B are provided has been described, but the number of gripping portions is not limited to two, and three or more gripping portions may be provided. good. Even when three or more gripping portions are provided, the driving force transmission mechanism including the link mechanism allows the gripping portions to move with the gripping surfaces in contact with the article always facing each other.

Furthermore, although an example in which one grip driving unit 7 is provided has been described, the present invention is not limited to this.
For example, the gears of the driving force transmission portion 8B and the driving force transmission portion 8C may be prevented from meshing, and two gripping driving portions 7 may be provided to independently drive the gripping portions 5A and 5B. Thereby, the first gripping portion 5A and the second gripping portion 5B can be moved independently. That is, even if the article sucked by the suction section 3 is biased to the left or right, the first gripping section 5A and the second gripping section 5B can be driven in accordance with the position of the side surface of the article. As a result, the gripping contact portions 11A and 11B, which are the gripping surfaces of the gripping portions 5A and 5B, can be vertically pressed against the side surfaces of the article, and the article can be gripped appropriately.

2. Operation Example of Picking System Next, an operation example of the picking system 50 having the configuration described above will be described with reference to FIGS. 11 to 13 .

Here, the control device 57 that controls the robot hand 1 has a first control mode, a second control mode, and a third control mode. The first control mode is a control mode in which an article is held by being gripped by the gripping portions 5A and 5B and by suction by the suction portion 3. FIG. A second control mode is a control mode in which an article is held only by gripping by the gripping portions 5A and 5B. The third control mode is a control mode in which the article is held only by suction by the suction section 3 .

The control device 57 switches the control mode based on information related to the article, such as the shape and size of the article and the orientation of the article placed on the carry-in conveyor 52 . The information about the article is created based on the information about the article photographed by the imaging device 55 or the information about the article stored in advance in the information storage device 58, for example. In addition, before the picking operation is performed, the control mode for the current picking operation is stored in the information storage device 58, and the control device 57 controls the robot hand 1 based on the control mode stored in the information storage device 58. You may make it

2-1. First Control Mode First, an example of picking operation in the first control mode will be described with reference to FIGS. 11A to 11D.
11A to 11D are explanatory diagrams showing the picking operation in the first control mode.

First, as shown in FIG. 11A, the control device 57 controls the transport robot based on the information captured by the imaging device 55 (see FIG. 1) and the information about the article 100 stored in the information storage device 58 (see FIG. 1). 51 (see FIG. 1). Then, the control device 57 controls the transport robot 51 to move the robot hand 1 above the article 100 to be transported. Here, the position to which the robot hand 1 is moved is a position where the article 100 can be sucked by the suction section 3 when the extension mechanism 4 is extended.

At this time, based on the information captured by the imaging device 55 and the information about the article 100 stored in the information storage device 58, the control device 57 determines that the distance between the gripping portions 5A and 5B is slightly larger than the width of the gripped article 100. Drive the grip drive unit 7 so as to increase the size. As a result, it is possible to shorten the operating time of the gripping drive unit 7 in gripping operations for gripping an article 100 with the gripping units 5A and 5B, which will be described later (see FIG. 11D). As a result, the picking work time can be shortened, and the throughput of the picking system 50 is improved.

Next, as shown in FIG. 11B, the control device 57 controls the telescopic mechanism 4 to extend the telescopic mechanism 4 toward the article 100. Then, as shown in FIG. Thereby, the adsorption part 3 can be brought closer to the article 100 . Further, as shown in FIG. 11A, since the gripping portions 5A and 5B are opened in advance, it is possible to prevent the suction portion 3 from contacting the gripping portions 5A and 5B when the extension mechanism 4 is extended. Then, when the adsorption unit 3 contacts the article 100 , the control device 57 drives a negative pressure generator (not shown), and the adsorption section 3 adsorbs the article 100 .

Next, the control device 57 drives the telescopic mechanism 4 to contract it. Thereby, as shown in FIG. 11C, the article 100 is pulled out from the storage cardboard box 200 . Also, the control device 57 controls the transport robot 51 to raise the article 100 together with the robot hand 1 . The retraction operation of the expansion mechanism 4 and the lifting operation of the robot hand 1 by the transport robot 51 may be performed simultaneously. Alternatively, the telescopic mechanism 4 may be contracted after the robot hand 1 has been lifted by the transport robot 51 .

Next, the control device 57 drives the grip driver 7 to close the grips 5A and 5B. Further, the control device 57 controls the gripping force of the gripping drive unit 7 to reach the predetermined gripping force F according to the article 100 as described above. Thereby, as shown in FIG. 11D, the side surfaces of the article 100 can be gripped by the gripping portions 5A and 5B.

In this way, the upper surface of the article 100 is sucked by the suction section 3, and after the article 100 is pulled up to a predetermined height, the side surfaces of the article 100 are held by the holding sections 5A and 5B. As a result, as shown in FIGS. 11A to 11D , even when the articles 100 are aligned and the gripping sections 5A and 5B cannot be inserted between the adjacent articles 100, the gripping sections 5A and 5B can hold the article 100. can be grasped.

Also, after gripping the article 100 by the gripping units 5A and 5B, the control device 57 controls the transport robot 51 to transport the article 100 to the unloading container 56 . At this time, the article 100 is held by the robot hand 1 by being sucked by the sucking section 3 and gripped by the gripping sections 5A and 5B.
Therefore, it is possible to prevent the article 100 from falling out of the robot hand 1 due to centrifugal force and inertial force generated during transportation.

If the article 100 is light in weight, after the operation shown in FIG. 11D, the adsorption by the adsorption unit 3 is stopped, and the article 100 is transported to the unloading container 56 by the transport robot 51 only by gripping the gripping units 5A and 5B. You may In this case, the driving energy of the adsorption part 3 can be reduced.

2-2. Second Control Mode Next, a picking operation example in the second control mode will be described with reference to FIGS. 12A to 12C.
12A to 12C are explanatory diagrams showing the picking operation in the second control mode.

Here, the second control mode is performed for an article 101 whose upper surface, that is, the size of the suction surface is smaller than that of the suction unit 3, such as the article 101 shown in FIGS. 12A to 12C.

First, as shown in FIG. 12A, the control device 57 controls the transport robot based on the information captured by the imaging device 55 (see FIG. 1) and the information about the article 101 stored in the information storage device 58 (see FIG. 1). 51 (see FIG. 1). Then, the control device 57 controls the transport robot 51 to move the robot hand 1 above the article 101 to be transported. Here, the position to which the robot hand 1 is moved is the position where the article 101 can be gripped when the gripping portions 5A and 5B are closed.

Based on the information captured by the imaging device 55 and the information on the article 101 stored in the information storage device 58, the control device 57 adjusts the distance between the gripping portions 5A and 5B to be slightly larger than the width of the article 101 to be gripped. , the grip drive unit 7 is driven. Further, the control device 57 controls the transport robot 51 to insert the gripping portions 5A and 5B so that the gripping portions 5A and 5B do not contact the adjacent articles 101 .

At this time, the expansion mechanism 4 is in the most contracted state, the suction unit 3 is in a state in which the negative pressure generating device (not shown) is stopped, and the article 101 is not suctioned.

　Next, as shown in FIG. 12B, the control device 57 drives the grip driver 7 to close the grips 5A and 5B. Further, the control device 57 controls the gripping force of the gripping drive unit 7 to reach the predetermined gripping force F according to the article 101 as described above. As a result, the side surfaces of the article 101 (in the example shown in FIG. 12B, the mouth of the article 101) can be gripped by the gripping sections 5A and 5B.

Next, as shown in FIG. 11C, the control device 57 controls the transport robot 51 to raise the article 101 together with the robot hand 1. Thereby, the article 101 can be pulled out from the storage cardboard box 200 .

Thus, by controlling the transport robot 51 and the robot hand 1 by the control device 57, the article 101 to be stored in the storage cardboard box 200 can be gripped only by the gripping portions 5A and 5B. Further, by gripping the side surface (mouth portion) of the article 101 as in this example, the article 101 such as a bottle or a PET bottle whose upper surface cannot be adsorbed by the adsorption portion 3 can be reliably gripped.

2-3. Third Control Mode Next, a picking operation example in the third control mode will be described with reference to FIGS. 13A to 13C.
13A to 13C are explanatory diagrams showing the picking operation in the third control mode.

Here, in the third control mode, for example, like the article 104 shown in FIGS. is also performed on the long article 104 .

First, as shown in FIG. 13A, the control device 57 controls the transport robot based on the information captured by the imaging device 55 (see FIG. 1) and the information on the article 104 stored in the information storage device 58 (see FIG. 1). 51 (see FIG. 1). Then, the control device 57 controls the transport robot 51 to move the robot hand 1 above the article 104 to be transported. Here, the position to which the robot hand 1 is moved is a position where the article 104 can be sucked by the suction section 3 when the extension mechanism 4 is extended.

The control device 57 drives the grip driving section 7 so that the distance between the gripping sections 5A and 5B is greater than the width of the suction section 3. Thereby, it is possible to prevent the suction portion 3 from coming into contact with the grip portions 5A and 5B when the extension mechanism 4 is extended.

　Next, as shown in FIG. 13B, the control device 57 controls the elastic mechanism 4 to extend the elastic mechanism 4 toward the article 100. Then, as shown in FIG. Thereby, the adsorption part 3 can be brought closer to the article 104 . Further, as shown in FIG. 13A, since the gripping portions 5A and 5B are opened in advance, it is possible to prevent the suction portion 3 from contacting the gripping portions 5A and 5B when the extension mechanism 4 is extended. Then, when the adsorption unit 3 contacts the article 104 , the control device 57 drives a negative pressure generator (not shown), and the adsorption section 3 adsorbs the article 104 .

Next, as shown in FIG. 13C , the control device 57 controls the transport robot 51 to move the robot hand 1 upward and lift the article 104 from the storage cardboard box 200 without contracting the expansion mechanism 4 . Here, when the expansion mechanism 4 is contracted, the article 104 may interfere with the gripping portions 5A and 5B. Therefore, by lifting the article 104 without contracting the telescopic mechanism 4, interference between the article 104 and the gripping portions 5A and 5B can be prevented. Furthermore, the operating time of the telescopic mechanism 4 can be shortened, and the picking work time can be shortened.

Thus, by controlling the transport robot 51 and the robot hand 1 with the control device 57, the article 104 to be stored in the storage cardboard box 200 can be transported by the suction unit 3 alone. By sucking the upper surface of the article 104 as in this example, it becomes possible to grip the article 104 having a width larger than the maximum width that can be gripped by the gripping portions 5A and 5B.

In the third control mode, since the side surfaces of the article 104 are not gripped by the gripping units 5A and 5B, the transport speed of the transport robot 51 is set lower than in the other first control mode and second control mode. . This can prevent the article 104 from falling out of the robot hand 1 .

Thus, in this example, by switching the control mode of the robot hand 1 to the first control mode, the second control mode, and the third control mode according to the shape, size, etc. of the articles 100, 101, 104, Various items 100, 101, 104 can be securely gripped.

It should be noted that the present invention is not limited to the embodiments described above and shown in the drawings, and various modifications are possible without departing from the gist of the invention described in the claims.

Also, an example in which the control device 57 that controls the entire picking system 50 is applied as the control device that controls the robot hand 1 has been described, but it is not limited to this. For example, a dedicated control device or information storage device for controlling the robot hand 1 may be provided.

In this specification, words such as "parallel" and "perpendicular" are used, but these do not strictly mean only "parallel" and "perpendicular", but include "parallel" and "perpendicular". Furthermore, it may be in a "substantially parallel" or "substantially orthogonal" state within the range where the function can be exhibited.

1...robot hand, 2...main body, 3...adsorption part, 4...extension mechanism, 5A, 5B...grip part, 6A, 6D...first link, 6B, 6E...third link, 6C, 6F...second link 7... Gripping drive part 8A... Main driving force transmission part 8B, 8C... Driving force transmission part 9A, 9B, 9C, 9D, 9E, 9F, 9G, 9H... Link joint 10A, 10B... Base, 10a ... first surface portion, 10b... second surface portion, 11A, 11B... gripping contact portion, 11C... protrusion, 20A, 20B... driving force transmission mechanism, 50... picking system, 51... transfer robot, 52... loading conveyor, 53... movement Mechanism 54 Unloading conveyor 55 Imaging device 56 Unloading container 57 Control device 58 Information storage device 100, 101, 102, 104 Articles 200 Storage cardboard

Claims (7)

1. a gripping portion for gripping an article;
   a grip drive unit that drives the grip unit;
   a driving force transmission mechanism that movably supports the gripping portion and transmits driving force from the gripping drive portion to the gripping portion;
   The driving force transmission mechanism has a plurality of links, and moves a gripping surface of the gripping portion that contacts the article in the same posture at all times.
2. an adsorption unit that adsorbs the article;
   a control device that controls driving of the adsorption unit and the grip drive unit;
   The control device has a first control mode in which the article is held by gripping by the gripping section and suction by the suction section, and a second control mode in which the article is held only by gripping by the gripping section.
   a third control mode in which the article is held by suction by the suction unit;
   The robot hand according to claim 1, wherein the control device switches between the first control mode, the second control mode, and the third control mode based on the information about the article.
3. further comprising a telescopic mechanism for telescopically supporting the suction part,
   When the telescopic mechanism is contracted, the suction part is positioned above the holding part in the vertical direction, and when the telescopic mechanism is expanded, the suction part is positioned below the holding part in the vertical direction. Item 3. The robot hand according to item 2.
4. A plurality of the gripping portions are provided,
   2. The robot hand according to claim 1, wherein the gripping surfaces of the plurality of gripping portions that contact the article always move in a state of facing each other due to the driving force transmission mechanism.
5. The robot hand according to claim 1, wherein a plurality of protrusions are provided on a gripping surface of the gripping portion that contacts the article.
6. The driving force transmission mechanism is
   a plurality of said links;
   a driving force transmission unit to which the driving force from the grip driving unit is transmitted;
   The robot hand according to claim 1, wherein at least one of the plurality of links is connected to the driving force transmission section.
7. a transport robot that transports an article;
   a robot hand provided on the transport robot,
   The robot hand
   a gripping portion that grips the article;
   a grip drive unit that drives the grip unit;
   a driving force transmission mechanism that movably supports the gripping portion and transmits driving force from the gripping drive portion to the gripping portion;
   The picking system, wherein the driving force transmission mechanism has a plurality of links, and always moves a gripping surface of the gripping unit that contacts the article in the same posture.

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