JP2025027539A - Grip device and method - Google Patents

Abstract

A gripping device and method are provided that can improve transport capacity.
[Solution] The device comprises an upper surface gripping portion having a first adsorption surface capable of adsorbing to the upper surface of an object, a determination portion which determines whether the upper surface gripping portion can be adsorbed to multiple objects and raised depending on the area of the upper surface of the objects and the arrangement of the objects, and a control portion which controls the movement of the upper surface gripping portion depending on the determination result of the determination portion.
[Selected figure] Figure 4

Description

The present disclosure relates to a gripping device and method for gripping an object.

There are known conveying devices such as palletizing devices that stack items on trays such as pallets. For example, Patent Document 1 describes a gripping device in a conveying device that sucks and grips the top surface of an item.

Patent No. 6793428

Generally, multiple items are stacked on a pallet. The gripping device picks up and transports the multiple items stacked on the pallet one by one. This poses an issue of long transport time for the gripping device, which makes work less efficient.

The present disclosure aims to solve the above-mentioned problems and provide a gripping device and method that can improve transport capacity.

To achieve the above object, the gripping device of the present disclosure includes an upper gripping unit having a first suction surface capable of adsorbing to the upper surface of an object, a determination unit that determines whether the upper gripping unit can be lifted by adsorbing to a plurality of objects according to the area of the upper surface of the object and the arrangement of the object, and a control unit that controls the movement of the upper gripping unit according to the determination result of the determination unit.

The gripping method disclosed herein also includes a step of providing an upper gripping unit having a first suction surface capable of adhering to the upper surface of an object, determining whether the upper gripping unit can be adsorbed to a plurality of objects and raised according to the area of the upper surface of the object and the arrangement of the object, and controlling the movement of the upper gripping unit when it is determined that the upper gripping unit can be adsorbed to a plurality of objects and raised.

The gripping device and method disclosed herein can improve transport capacity.

FIG. 1 is a schematic diagram of a gripping device according to the present embodiment. FIG. 2 is a schematic diagram showing a 90° flip-up state of the gripping device shown in FIG. FIG. 3 is a schematic diagram showing a 180° flip-up state of the gripping device shown in FIG. FIG. 4 is a schematic block diagram of the gripping device shown in FIG. FIG. 5 is a flowchart illustrating a process flow of the control device. FIG. 6 is a plan view for explaining a typical unloading operation by the gripping device. FIG. 7 is a cross-sectional view taken along the line II-II shown in FIG. FIG. 8 is a cross-sectional view showing the state after FIG. FIG. 9 is a plan view for explaining a schematic result of a determination as to whether or not multiple objects can be picked up by the gripping device. FIG. 10 is a plan view for explaining a schematic result of a determination as to whether or not multiple objects can be picked up by the gripping device. FIG. 11 is a plan view for explaining a schematic result of a determination as to whether or not multiple objects can be picked up by the gripping device. FIG. 12 is a plan view for explaining a schematic result of a determination as to whether or not multiple objects can be picked up by the gripping device. FIG. 13 is a plan view for explaining a schematic result of a determination as to whether or not multiple objects can be picked up by the gripping device.

Below, the embodiments of the present disclosure are described in detail with reference to the drawings. Note that the present invention is not limited to these embodiments. Furthermore, the components in the following embodiments include those that are replaceable and easy for a person skilled in the art, those that are substantially the same, or those that are equivalent. Furthermore, the components in the following embodiments can be omitted, replaced, or modified in various ways without departing from the gist of the present disclosure. In the following embodiments, the components necessary for illustrating the embodiments are described, and other components are omitted. The same components are given the same reference numerals, and different components are given different reference numerals.

[Embodiment]
<Configuration of gripping device>
Fig. 1 is a schematic diagram of a gripping device according to this embodiment. Fig. 2 is a schematic diagram showing a 90° flip-up mode of the gripping device shown in Fig. 1. Fig. 3 is a schematic diagram showing a 180° flip-up mode of the gripping device shown in Fig. 1. Fig. 4 is a schematic block diagram of the gripping device shown in Fig. 1. The gripping device 1 shown in Figs. 1 to 4 is a device that is attached to a palletizing device as a conveying device, and stacks articles on a pallet, unloads articles from a pallet, or transfers articles from an arbitrary pallet to another pallet in a facility that is managed by logistics such as a warehouse.

The Japan Pallet Association defines a pallet as "a surface on which cargo can be placed in a single unit, and a structure that allows loading, transporting, and storage all by hand or by special vehicles such as forklifts. This includes those with superstructures." In this embodiment, a pallet refers to a container or platform on which goods R are loaded. In other words, the pallet referred to here is not limited to a so-called flat platform, but also includes a basket cart and may be of any shape. Goods R are loaded onto a pallet, such as goods to be shipped. The term "goods R" includes cardboard boxes and the like in which goods are packed. At least the top surface Ra of the goods R is flat, and in this embodiment, a cardboard box having a rectangular or cubic shape is assumed.

As shown in Figs. 1 to 3, the gripping device 1 includes a base 10, an upper gripping unit 20, a side gripping unit 30, a first arm 40, a second arm 50, and a flip-up mechanism 60. As shown in Fig. 4, the gripping device 1 further includes an imaging device 70, an input/output device 80, and a control device 90 that controls the operation of each part of the gripping device 1. Note that in this embodiment, the gripping device 1 including the imaging device 70, the input/output device 80, and the control device 90 includes an embodiment in which the functions of each device are configured as part of the functions of a palletizing device to which the gripping device 1 is attached, or a conveying system to which the palletizing device is deployed.

In this embodiment, the items R are stacked on a pallet, with the upper side in the vertical direction being the top surface Ra, and the side in the horizontal direction perpendicular to the vertical direction being the side surface Rb. The direction perpendicular to the second opposing surface 30a that faces the side surface Rb of the item R when the side gripping unit 30 supports the side surface Rb of the item R is defined as the X-axis direction, the direction parallel to the rotation axis A of the flip-up mechanism 60 is defined as the Y-axis direction, and the direction perpendicular to the X-axis and Y-axis directions and perpendicular to the first opposing surface 20a that faces the top surface Ra of the item R when the top gripping unit 20 supports the top surface Ra of the item R is defined as the Z-axis direction. At least during operation of the gripping device 1, the X-axis and Y-axis directions correspond to the horizontal direction, and the Z-axis direction corresponds to the vertical direction.

The base 10 shown in Figures 1 to 3 is connected to the tip of the arm of the palletizing device to which the gripping device 1 is attached via a pivoting shaft 12, a rotation mechanism 14, and a lifting mechanism 16. The pivoting shaft 12 is fixed to the upper surface side of the base 10 so that its axis is parallel to the Z-axis direction. The base 10 and the pivoting shaft 12 are supported rotatably in a rotational direction φ around the axis of the pivoting shaft 12 relative to the arm of the palletizing device.

The turning mechanism 14 shown in FIG. 4 turns the base 10 and the turning shaft 12 in a rotation direction φ. For example, if the palletizing device is a multi-joint robot, the turning of the turning shaft 12 by the turning mechanism 14 corresponds to the operation of the sixth axis of the multi-joint robot. The turning mechanism 14 is realized by a well-known mechanism such as a rotary actuator including a motor, a rack-and-pinion mechanism including an air cylinder, or a wire or link mechanism. The operation of the turning mechanism 14 is controlled by the control unit 96 of the control device 90.

The lifting mechanism 16 linearly moves the base 10 and the swivel shaft 12 in the vertical direction V parallel to the Z-axis direction. For example, if the palletizing device is a multi-joint robot, the linear movement of the swivel shaft 12 by the lifting mechanism 16 is achieved by the cooperative operation of multiple axes of the multi-joint robot. If the palletizing device is a Cartesian coordinate robot, the linear movement of the swivel shaft 12 by the lifting mechanism 16 corresponds to the operation of a vertical linear joint of the Cartesian coordinate robot. In this case, the lifting mechanism 16 is achieved by a well-known mechanism such as a linear actuator including a motor and an air cylinder, a rack and pinion mechanism, etc. The operation of the lifting mechanism 16 is controlled by the control unit 96 of the control device 90.

The top gripping part 20 is provided on the lower part of the base 10. The top gripping part 20 has a first opposing surface 20a on its lower surface that faces the top surface Ra of the item R. The top gripping part 20 is fixed to the base 10 so that the first opposing surface 20a is perpendicular to the Z-axis direction. The top gripping part 20 rises and falls and rotates in accordance with the rising and lowering movements and rotation movements of the base 10 and the rotating shaft part 12. The top gripping part 20 has a first suction part 22 on the first opposing surface 20a that can suction the item R.

In the examples shown in Figs. 1 to 3, the first suction unit 22 is depicted as a single block shape, but may be, for example, a plurality of suction pads protruding downward from the first opposing surface 20a of the upper gripping unit 20. The first suction unit 22 has a first suction surface 22a at its lower end. When the first suction surface 22a is in contact with the upper surface Ra of the article R, the first suction mechanism 24 shown in Fig. 4 is activated, so that the first suction surface 22a of the first suction unit 22 is suctioned to the upper surface Ra of the article R. The first suction mechanism 24 includes, for example, a vacuum generator that is connected to the first suction surface 22a via an air pipe (not shown) and sucks air from the first suction surface 22a. For example, when the first suction unit 22 is composed of a plurality of suction pads, each suction pad is connected to the first suction mechanism 24, which is a vacuum generator, via an air pipe. The operation of the first suction mechanism 24 is controlled by the control unit 96 of the control device 90.

The side gripping unit 30 is provided on the side of the base 10 in the X-axis direction via the first arm 40, the second arm 50, and the flip-up mechanism 60. The side gripping unit 30 has a second opposing surface 30a that faces the side surface Rb of the article R. The side gripping unit 30 can move in the longitudinal direction of the first arm 40 relative to the base 10 by the first telescopic mechanism 44 described later. The side gripping unit 30 can also move in the longitudinal direction of the second arm 50 relative to the base 10 by the second telescopic mechanism 54 described later. The side gripping unit 30 can also rotate in a rotation direction θ around the rotation axis A of the flip-up mechanism 60 relative to the base 10 by the flip-up mechanism 60. The rotation axis A is a horizontal axis parallel to both the first suction surface 22a of the upper gripping unit 20 and the second suction surface 32a of the side gripping unit 30.

The side gripping unit 30 can move relative to the top gripping unit 20 in the X-Z plane by the first telescopic mechanism 44, the second telescopic mechanism 54, and the flip-up mechanism 60. In other words, the first telescopic mechanism 44 and the second telescopic mechanism 54 are movement mechanisms that move the side gripping unit 30 relative to the top gripping unit 20. The side gripping unit 30 of this embodiment does not move relative to the top gripping unit 20 in the Y-axis direction, but may be configured to be able to move relative to the Y-axis direction. The side gripping unit 30 has a second suction unit 32 on the second opposing surface 30a that can suction the item R.

In the examples shown in Figs. 1 to 3, the second suction portion 32 is depicted as a single block shape, but may be, for example, a plurality of suction pads protruding from the second opposing surface 30a of the side gripping portion 30. The second suction portion 32 has a second suction surface 32a at the end opposite to the second opposing surface 30a side. When the second suction surface 32a is in contact with the side surface Rb of the article R, the second suction mechanism 34 shown in Fig. 4 is activated, so that the second suction surface 32a of the second suction portion 32 is suctioned to the side surface Rb of the article R. The second suction mechanism 34 includes, for example, a vacuum generator that is connected to the second suction surface 32a via an air pipe (not shown) and sucks air from the second suction surface 32a. For example, when the second suction portion 32 is composed of a plurality of suction pads, each suction pad is connected to the second suction mechanism 34, which is a vacuum generator, via an air pipe. The operation of the second suction mechanism 34 is controlled by the control unit 96 of the control device 90.

In the state shown in FIG. 1 where the longitudinal direction of the first arm 40 is parallel to the X-axis direction and the longitudinal direction of the second arm 50 is parallel to the Z-axis direction, the second opposing surface 30a of the side gripping portion 30 faces the side surface Rb of the article R. At this time, the second suction surface 32a of the second suction portion 32 faces the side surface Rb of the article R. Also, at this time, the entire surface of the second suction surface 32a is located below the first suction surface 22a. In the state shown in FIG. 2 where the longitudinal direction of the first arm 40 is parallel to the Z-axis direction and the longitudinal direction of the second arm 50 is parallel to the X-axis direction, the second opposing surface 30a faces vertically downward. At this time, the second suction surface 32a of the second suction portion 32 faces vertically downward. Also, at this time, the second suction surface 32a is located above the first suction surface 22a by a distance B.

The first arm 40 is provided on the side of the base 10 in the X-axis direction via the second arm 50 and the flip-up mechanism 60. The first arm 40 has a first support 42 and a first telescopic mechanism 44. The first support 42 is located at one end side of the longitudinal direction of the first arm 40. The first support 42 is connected to the second arm 50. The first support 42 supports the first telescopic mechanism 44 and is connected to the side grip 30 via the first telescopic mechanism 44. In this embodiment, the first support 42 has a frame shape that accommodates and supports the first fixed portion 44a of the first telescopic mechanism 44. The first telescopic mechanism 44 extends along the longitudinal direction of the first arm 40 and is telescopic in a first telescopic direction F1, which is the longitudinal direction of the first arm 40. In the state shown in FIG. 1, in which the longitudinal direction of the first arm 40 is parallel to the X-axis direction and the longitudinal direction of the second arm 50 is parallel to the Z-axis direction, the first extension mechanism 44 is expanded and contracted in advance to match the width dimension w of the article R so that the second suction surface 32a abuts against the side surface Rb of the article R.

In this embodiment, the first telescopic mechanism 44 includes a first fixed part 44a and a first movable part 44b. The first fixed part 44a is fixed to the first support part 42. The first fixed part 44a supports the first movable part 44b so that the first movable part 44b can move linearly in the first telescopic direction F1 within a predetermined range. The first movable part 44b can move in the first telescopic direction F1 relative to the first fixed part 44a. One end side of the first movable part 44b in the longitudinal direction is supported by the first fixed part 44a. The other end side of the first movable part 44b in the longitudinal direction is fixed to the side grip part 30. The first telescopic mechanism 44 is realized by a well-known mechanism such as a cylinder having a cylindrical first fixed part 44a and a rod-shaped first movable part 44b, an electric actuator, a wire, or a link mechanism.

The second arm 50 is provided on the side of the base 10 in the X-axis direction via a flip-up mechanism 60. The second arm 50 has a second support 52 and a second telescopic mechanism 54. The second support 52 is located at one end of the longitudinal direction of the second arm 50. The second support 52 is connected to the flip-up mechanism 60. The second support 52 supports the second telescopic mechanism 54 and is connected to the first support 42 of the first arm 40 via the second telescopic mechanism 54. In this embodiment, the second support 52 has a frame shape that accommodates and supports the second fixed portion 54a of the second telescopic mechanism 54. The second telescopic mechanism 54 extends along the longitudinal direction of the second arm 50 and is telescopic in a second telescopic direction F2, which is the longitudinal direction of the second arm 50. In the embodiment shown in FIG. 1, in which the longitudinal direction of the first arm 40 is parallel to the X-axis direction and the longitudinal direction of the second arm 50 is parallel to the Z-axis direction, the second extension mechanism 54 is pre-extended to match the height dimension h of the article R so that the second suction surface 32a abuts at a suitable height position on the side surface Rb of the article R.

In this embodiment, the second telescopic mechanism 54 includes a second fixed part 54a and a second movable part 54b. The second fixed part 54a is fixed to the second support part 52. The second fixed part 54a supports the second movable part 54b so that the second movable part 54b can move linearly in the second telescopic direction F2 within a predetermined range. The second movable part 54b can move in the second telescopic direction F2 relative to the second fixed part 54a. One end side of the second movable part 54b in the longitudinal direction is supported by the second fixed part 54a. The other end side of the second movable part 54b in the longitudinal direction is fixed to the first support part 42 of the first arm part 40. The second telescopic mechanism 54 is realized by a well-known mechanism such as a cylinder having a cylindrical second fixed part 54a and a rod-shaped second movable part 54b, an electric actuator, a wire, or a link mechanism.

The flip-up mechanism 60 can be switched between a first state (as shown in FIG. 1) in which the side gripping portion 30 is positioned below the lower end of the upper gripping portion 20 (in this embodiment, the first suction surface 22a of the first suction portion 22) and a second state (as shown in FIGS. 2 and 3) in which the side gripping portion 30 is positioned above the lower end of the upper gripping portion 20. The flip-up mechanism 60 is connected to the upper gripping portion 20 via the base 10. The flip-up mechanism 60 is also connected to the side gripping portion 30 via the first arm portion 40 and the second arm portion 50. The flip-up mechanism 60 of this embodiment is provided on the side of the base 10 in the X-axis direction. The flip-up mechanism 60 rotates the second arm portion 50, the first arm portion 40, and the side gripping portion 30 relative to the base 10 in a rotation direction θ around a rotation axis A parallel to the Y-axis direction.

In this embodiment, the flip-up mechanism 60 has a fixed part 62 and a rotating part 64. The fixed part 62 is fixed to the connecting part 10a of the base 10. That is, the fixed part 62 moves integrally with the base 10 and the upper grip part 20. The rotating part 64 can rotate in a rotation direction θ around the rotation axis A relative to the fixed part 62. The rotating part 64 is fixed to the second support part 52 of the second arm part 50. The flip-up mechanism 60 is realized by a well-known mechanism such as a rotary actuator including a motor, a rack and pinion mechanism including an air cylinder, a wire or link mechanism, etc. The flip-up mechanism 60 has a locking mechanism (not shown) that can position the position of the rotation direction θ of the rotating part 64 relative to the fixed part 62. The locking mechanism is realized by a well-known mechanism such as an air lock using high-pressure air, a mechanical lock using a motor drive, or a solenoid lock using an electromagnetic solenoid.

The flip-up mechanism 60 allows the side gripping portion 30, the first arm portion 40, and the second arm portion 50 to rotate in the rotation direction θ around the rotation axis A between the 0° position shown in FIG. 1, the 90° position shown in FIG. 2, and the 180° position shown in FIG. 3. In addition, the side gripping portion 30, the first arm portion 40, and the second arm portion 50 can be positioned at any position between the 0° position shown in FIG. 1 and the 180° position shown in FIG. 3 by a locking mechanism (not shown). In the 0° position shown in FIG. 1, the first arm portion 40 is located lower than the second arm portion 50, and the second suction surface 32a of the side gripping portion 30 is located lower than the first suction surface 22a of the upper gripping portion 20 and faces the side surface Rb of the article R. In the 90° position shown in FIG. 2, the second suction surface 32a of the side gripping portion 30 faces vertically downward and is located a distance B above the first suction surface 22a of the upper gripping portion 20. In the 180° position shown in FIG. 3, the second suction surface 32a of the side gripping portion 30 faces the X-axis direction opposite the base portion 10, and the first arm portion 40 is positioned above the second arm portion 50.

The imaging device 70 captures an image of a pallet on which the item R is to be loaded or unloaded, the items R loaded on the pallet, and the stacked arrangement of the items R, and outputs image data that can identify the position and individual items of the imaged objects to the control device 90. The imaging device 70 is disposed in a position where the pallet and the items R loaded on the pallet can be observed. At this time, the imaging device 70 captures an image of all (multiple) items R loaded on the pallet, thereby capturing an image of the stacked arrangement of the multiple items R, that is, the layout of the multiple items R. The imaging device 70 may be attached to the gripping device 1, or may be disposed separately from the gripping device 1. The imaging device 70 includes one or more cameras.

The input/output device 80 includes an input device through which the worker inputs various pieces of information for operating the gripping device 1, and an output device for presenting the various pieces of information to the worker. The input device is realized, for example, by a keyboard, a mouse, a physical switch, a button, or a touch panel. The output device is realized, for example, by a display device including a liquid crystal display device, an organic EL (Electro Luminescence) display device, a light-emitting device including an LED (Light Emitting Diode), or a speaker. The input/output device 80 may be an information terminal capable of inputting and outputting various pieces of information.

The control device 90 is a computer that controls the gripping device 1. The control device 90 has a communication unit 92, a storage unit 94, a control unit 96, and a determination unit 97. The communication unit 92 is a module used by the control unit 96 to communicate with an external device such as the management device 100, and may include, for example, an antenna. In this embodiment, the communication method by the communication unit 92 is assumed to be wireless communication, but the communication method may be arbitrary. The storage unit 94 is a memory that stores the calculation contents and programs of the control unit 96, and various information obtained from the management device 100 via the communication unit 92, and includes, for example, at least one of a RAM (Random Access Memory), a main storage device such as a ROM (Read Only Memory), and an external storage device such as a HDD (Hard Disk Drive).

The control unit 96 is an arithmetic processing device, and includes, for example, an arithmetic circuit such as a CPU (Central Processing Unit). The control unit 96 executes various processes by reading and executing programs (software) from the storage unit 94. The control unit 96 may execute processes using one CPU, or may be provided with multiple CPUs and execute processes using the multiple CPUs.

The control unit 96 acquires upstream data from the management device 100 via the communication unit 92. The upstream data includes, for example, transport target data such as the type, weight, and dimensions of the items R to be loaded on the pallet, the perforations or zipper parts of the box, the number of glued items, the number of items R, the arrangement of each item R on the pallet or the position where the items R are loaded on the pallet, the order in which the items R are unloaded from the pallet or the order in which they are loaded on the pallet, etc. The control unit 96 causes the imaging device 70 to capture an image at any timing and acquires image data. The control unit 96 processes the acquired image data to recognize the number, position, shape, size, etc. of the items R present in the image data.

The control unit 96 determines the transport parameters of the upper gripping unit 20 and the side gripping unit 30 based on the image data and the transport target data. In this case, the image data does not need to be used. Here, the transport parameters include the rotation speed and rotation acceleration of the upper gripping unit 20 and the side gripping unit 30 by the rotation mechanism 14, the rising speed and rising acceleration of the upper gripping unit 20 and the side gripping unit 30 by the lifting mechanism 16, the suction pressure and suction time of the item R by the first suction mechanism 24, and the suction pressure and suction time of the item R by the second suction mechanism 34. In addition, the control unit 96 determines the transport parameters of the side gripping unit 30 based on the image data and the transport target data. Here, the transport parameters include whether or not the side gripping unit 30 needs to grip the side, and the flip-up direction and angle of the side gripping unit 30. In this case, the image data is used. That is, the transport parameters are whether or not the first telescopic mechanism 44, the second telescopic mechanism 54, and the flip-up mechanism 60 need to be operated, and the telescopic speed and telescopic acceleration. The control unit 96 controls the turning mechanism 14, the lifting mechanism 16, the first suction mechanism 24, the second suction mechanism 34, the first telescopic mechanism 44, the second telescopic mechanism 54, and the flip-up mechanism 60 based on the transport parameters. The control unit 96 also executes control to move the gripping device 1 itself in the horizontal direction in the palletizing device to which the gripping device 1 is attached. When the palletizing device is a multi-joint robot, the horizontal movement of the gripping device 1 itself is achieved by the cooperative operation of multiple axes of the multi-joint robot.

Like the control unit 96, the determination unit 97 is an arithmetic processing device, and includes an arithmetic circuit such as a CPU (Central Processing Unit). The determination unit 97 executes various processes by reading and executing a program (software) from the storage unit 94. The determination unit 97 may be integrated with the control unit 96 and provided as one of the functions of the control unit 96.

The determination unit 97, like the control unit 96, acquires upstream data from the management device 100 via the communication unit 92. The upstream data includes transport target data such as at least the weight of the items R to be stacked on the pallet, the perforations or zipper parts of the box, and the number of glue points. The determination unit 97 executes imaging by the imaging device 70 at any timing and acquires image data. The determination unit 97 processes the acquired image data to recognize the arrangement (layout), size, etc. of the multiple items R present in the image data. The determination unit 97 may acquire the transport target data, image data, etc. from the control unit 96.

The determination unit 97 determines whether the upper surface gripping unit 20 can be lifted by adsorbing to multiple objects R, depending on the area of the upper surface Ra of the objects R and the arrangement (layout) of the objects R. The determination unit 97 outputs the determination result to the control unit 96. The control unit 96 controls the movement of the upper surface gripping unit 20 depending on the determination result of the determination unit 97. That is, the determination unit 97 determines whether the upper surface gripping unit 20 can be lifted by adsorbing to multiple objects R, or whether the upper surface gripping unit 20 cannot be lifted by adsorbing to multiple objects R, and can only be lifted by adsorbing one object R. When the determination unit 97 determines that the upper surface gripping unit 20 can be lifted by adsorbing to multiple objects R, the control unit 96 moves the upper surface gripping unit 20 to a position facing the upper surfaces Ra of the multiple objects R. On the other hand, when the determination unit 97 determines that the upper surface gripping unit 20 is capable of adsorbing and lifting to one item R, the control unit 96 moves the upper surface gripping unit 20 to a position facing the upper surface Ra of the single item R.

At this time, the determination unit 97 compares the suction area of the upper gripping unit 20 with the total area of the upper surfaces Ra of the multiple objects R, and when the suction area is equal to or greater than the determination ratio (e.g., 70%) of the total area, it determines that the upper gripping unit 20 can suction the multiple objects R and rise. Here, the suction area of the upper gripping unit 20 is the area of the first suction surface 22a of the first suction portion 22 of the upper gripping unit 20. Also, when multiple objects R are arranged adjacent to each other, it is the total area of the upper surfaces Ra of each object R. In this case, when multiple objects R are arranged adjacent to each other and there is a gap between adjacent objects R, the total area includes the area of the upper surfaces of the gap. In this embodiment, the determination ratio is set to 70%, but is not limited to this value. For example, the determination ratio may be adjusted according to the weight of one object R. For example, if the weight of one item R is greater than the reference value, the judgment ratio is set to greater than 70%, and if the weight of one item R is less than the reference value, the judgment ratio is set to less than 70%.

The determination unit 97 also determines whether or not side gripping by the side gripping unit 30 is necessary based on the image data and the transport object data. The control unit 96 controls the movement of the side gripping unit 30 according to the determination result of the determination unit 97. Specifically, the determination unit 97 determines that suction to the side Rb of the item R by the side gripping unit 30 is necessary when the length of the perforation or zipper portion of the upper surface Ra of the item R is longer than the length of one side of the upper surface Ra of the item R. The length of the perforation or zipper portion or one side of the item R may be image data or transport object data. Here, the perforation or zipper portion of the upper surface Ra of the item R and one side of the upper surface Ra of the item R are approximately parallel. Also, the length of the perforation or zipper portion of the upper surface Ra of the item R is not the length along one side of the upper surface Ra of the item R, but the actual length. In addition, when the number of perforations or zippers on the top surface Ra of the article R is greater than a preset reference number, the determination unit 97 determines that the side gripping unit 30 needs to adhere to the side surface Rb of the article R. It is preferable to set the reference number in advance through experiments, simulations, etc.

In addition, when the number of glue points on the top surface Ra of the item R is less than a preset reference number, the determination unit 97 determines that the side gripping unit 30 needs to adhere to the side surface Rb of the item R. Here, the number of glue points on the top surface Ra of the item R is the transport target data, and the reference number is set in advance through experiments, simulations, etc.

The management device 100 is a system that manages the operation of each device in a logistics management facility in which the gripping device 1 of this embodiment is deployed. The management device 100 is, for example, a WCS (Warehouse Control System) or a WMS (Warehouse Management System), but is not limited to a WCS or a WMS and may be any system, for example, a back-end system such as other production management systems. The location at which the management device 100 is installed is arbitrary, and it may be installed within the facility in which the gripping device 1 is deployed, or it may be installed at a location away from the facility to manage the facility from that location.

<Processing of the control device>
Next, a process flow for determining whether or not side gripping by the side gripping unit 30 is required during transportation by the gripping device 1 will be described. Here, a case where a plurality of items R stacked on a pallet is unloaded will be described. FIG. 5 is a flowchart illustrating a process flow of the control device. The process shown in FIG. 5 is executed by the control unit 96 of the control device 90 based on a program and data previously stored in the memory unit 94. For example, the control device 90 receives a predetermined control signal from the management device 100 instructing the driving of the gripping device 1, and then proceeds to step S10 shown in FIG. 5 to start the process.

The control device 90 acquires the transport target data (step S10). In this embodiment, the control device 90 acquires the transport target data from the management device 100 via the communication unit 92. In this process, the transport target data includes at least data that serves as a basis for determining whether the upper gripping unit 20 can adsorb and lift multiple objects R when lifting each object R to be unloaded by the gripping device 1, and data that serves as a basis for determining whether side gripping by the side gripping unit 30 is necessary. For example, if the object R is small and light, side gripping is not necessary. The transport target data also includes data indicating the number and position (coordinates on the pallet) of each object R to be unloaded, and the order of unloading.

The control device 90 sets the execution count i to i=1 and starts the loop process (step S12). In the loop process, while i≦n is true, the process from step S14 to step S20 is repeated n times. Note that n is the number of items R loaded on the pallet, and i indicates the order in which the items R are unloaded from the pallet.

The control device 90 acquires the captured image data (step S14). In this embodiment, the control device 90 causes the imaging device 70 to capture an image of a predetermined area including the i-th item R to be unloaded. In this case, the imaging device 70 outputs captured image data indicating data of the captured image to the control device 90. The captured image data may be linked to coordinate data of a coordinate system based on a predetermined position of the gripping device 1 or the facility in which the gripping device 1 is deployed. The control device 90 processes the captured image data to recognize the position, shape, size, arrangement (layout), etc. of the i-th item R to be unloaded.

The control device 90 determines whether the upper gripping portion 20 can be lifted by adsorbing multiple objects R (step S16). In this embodiment, the control device 90 determines whether multiple objects R can be picked up based on the image data acquired in step S14. For example, when the suction area of the upper gripping portion 20 is equal to or greater than a determined proportion (e.g., 70%) of the total area of the upper surface Ra of the multiple objects R, it is determined that the upper gripping portion 20 can be lifted by adsorbing multiple objects R. On the other hand, when the suction area of the upper gripping portion 20 is less than a determined proportion (e.g., 70%) of the total area of the upper surface Ra of the multiple objects R, it is determined that the upper gripping portion 20 cannot be lifted by adsorbing multiple objects R, and can only lift one object R. When the control device 90 determines that the upper gripping portion 20 is capable of adsorbing and lifting multiple items R, it moves the upper gripping portion 20 to a position facing the upper surface Ra of the multiple items R, and when it determines that the upper gripping portion 20 is capable of adsorbing and lifting one item R, it moves the upper gripping portion 20 to a position facing the upper surface Ra of the single item R.

The control device 90 determines whether side gripping is necessary (step S18). In this embodiment, the control device 90 determines whether side gripping is necessary based on the transport target data acquired in step S10. For example, if the i-th item R to be unloaded can be sufficiently lifted by the upper gripping unit 20 alone, it is determined that side gripping is unnecessary. If the control device 90 determines that side gripping is necessary (step S18; Yes), it proceeds to step S22. If the control device 90 determines that side gripping is not necessary (step S18; No), it proceeds to step S20.

When the control device 90 determines that side gripping is not necessary (step S18; No), it determines the flip-up direction and angle of the side gripping unit 30 based on the captured image data acquired in step S14 (step S20). The flip-up direction indicates the position of the side gripping unit 30 in the φ rotation direction. The flip-up angle indicates the position of the side gripping unit 30 in the θ rotation direction. If there is an obstacle around the i-th item R to be unloaded, the side gripping unit 30 may interfere with the obstacle. Specifically, if another item R is loaded adjacent to the side gripping unit 30 side of the item R (to the right as shown in FIG. 1), the side gripping unit 30 may interfere with the adjacent item R when the upper gripping unit 20 abuts against the upper surface Ra of the item R.

The positions of the side gripping unit 30 in the θ rotation direction and the φ rotation direction at the start of step S20 are, for example, the positions of the side gripping unit 30 when the i-1th item R is unloaded. In step S20, the control device 90 first acquires the position of the side gripping unit 30 in the φ rotation direction. The control device 90 then determines whether there are other items R that would be an obstacle in the direction of the side gripping unit 30 relative to the i-th item R, based on the captured image data acquired in step S14. If the control device 90 determines that there are no other items R that would be an obstacle, it decides to maintain the flip-up direction and angle of the side gripping unit 30, and proceeds to step S22.

When the control device 90 determines that there is another object R that is an obstacle, it determines the flip-up angle of the side gripping unit 30 so that the side gripping unit 30 can avoid the obstacle. When the control device 90 determines, for example, based on at least one of the transport target data and the captured image data, that the height dimension h of the other object R that is an obstacle is equal to or less than the height dimension h of the i-th object R, it determines the flip-up angle to be 90° (the position shown in FIG. 2). When the control device 90 determines, for example, based on at least one of the transport target data and the captured image data, that the height dimension h of the other object R that is an obstacle is greater than the height dimension h of the i-th object R and is smaller than a predetermined threshold, it determines the flip-up angle to be 180° (the position shown in FIG. 3). The predetermined threshold is set in advance by the configuration of the gripping device 1 other than the side gripping unit 30. For example, in the configuration of this embodiment, the predetermined threshold is set within a range where the second support unit 52 does not interfere at the 180° position shown in FIG. 3.

When the control device 90 determines, for example, based on at least one of the transport target data and the captured image data, that the height dimension h of the other obstructing object R is equal to or greater than a predetermined threshold, it decides to move the side gripping unit 30 in the φ rotation direction. The control device 90 determines the flip-up angle at which the side gripping unit 30 can avoid the other obstructing object R using the above procedure when the side gripping unit 30 has moved 90°, 180°, or 270° in the φ rotation direction. When the control device 90 determines the flip-up direction and angle of the side gripping unit 30, it proceeds to step S22.

The control device 90 transports (unloads) the i-th item R (step S22). The control device 90 first controls the swivel mechanism 14 and the flip-up mechanism 60 according to the flip-up direction and angle determined in step S18, and positions the side gripping unit 30 in a predetermined position. When performing side gripping by the side gripping unit 30, the control device 90 controls the first telescopic mechanism 44 and the second telescopic mechanism 54 to extend and retract the first arm 40 and the second arm 50 based on the width dimension w of the i-th item R (see FIG. 1) so that the side gripping unit 30 is positioned at a suitable position on the side Rb of the item R.

Next, the control device 90 controls the gripping device 1 to move horizontally until the first suction portion 22 of the upper gripping portion 20 faces the upper surface Ra of the article R. Next, the control device 90 controls the lifting mechanism 16 to lower the base 10 and the upper gripping portion 20 to a position where the first suction surface 22a of the first suction portion 22 abuts the upper surface Ra of the article R. Next, the control device 90 operates the first suction mechanism 24 to suction the upper surface Ra of the article R to the first suction surface 22a. If it is determined in step S16 that side gripping is necessary, the control device 90 operates the second suction mechanism 34 to suction the side surface Rb of the article R to the second suction surface 32a. As a result, the gripping device 1 supports the article R. The control device 90 uses the lifting mechanism 16 to raise the gripping device 1 gripping the article R, transports it to a predetermined position, and unloads the i-th item R from the pallet.

The control device 90 resets the execution count i in the loop process to i = i + 1, and returns to step S14 (step S24). After executing the processes from step S14 to step S22 n times and completing the unloading of n items R from the pallet, the loop process ends.

In the process of this embodiment shown in FIG. 5, step S14 is performed for each item R, but for example, when items R are arranged in a flat line on a pallet, i.e., when multiple items R are not stacked vertically, step S14 of imaging all items R on the pallet may be performed only the first time. Also, in the process of this embodiment, the number and position (coordinate) data of each item R are included in the transport target data, but the number and positions of items R may be obtained based on image data of all items R on the pallet.

Although the above description is of the process for unloading multiple items R from a pallet on which they are stacked, the process of this embodiment shown in FIG. 5 can also be applied to the case of stacking multiple items R on a pallet. In this case, in step S14, an image of a predetermined area including the area on the pallet where the items R are to be stacked is captured. In addition, in step S20, when stacking the i-th item R at a predetermined position on the pallet, the direction and angle of the bounce are determined based on the presence and size of an obstacle in an area adjacent to the area where the item R is to be stacked. The obstacles in this case are the 1st to i-1th items R stacked.

The determination by the control device 90 of whether the upper gripping unit 20 can be lifted by adsorbing to multiple objects R (step S16) and the determination of whether side gripping by the side gripping unit 30 is required (step S18) are not limited to those described above. For example, when the control device 90 determines that the upper gripping unit 20 is adsorbed to multiple objects R and cannot be lifted, it executes a determination of whether side gripping by the side gripping unit 30 is required. In other words, if the side gripping unit 30 is gripping the side, the control device 90 determines whether the upper gripping unit 20 can be lifted by adsorbing to multiple objects R.

<Unloading operation>
FIG. 6 is a plan view for explaining the unloading operation by the gripping device. FIG. 7 is a cross-sectional view taken along the line II-II shown in FIG. 6. FIG. 8 is a cross-sectional view showing the state after FIG. 7. FIGS. 6 to 8 show the operation of unloading the item R4 among the items R1, R2, R3, and R4 arranged on the pallet P. The items R1, R2, R3, and R4 all have the same dimensions. The item R4 is arranged adjacent to the item R3 on the left side in the plan view shown in FIG. 6. Also, in FIGS. 6 to 8, only the upper gripping portion 20 and the side gripping portion 30 of the gripping device 1 are depicted. Also, the side gripping portion 30 is assumed to be in the 90° position shown in FIG. 2.

As shown in Figures 6 and 7, when the first suction portion 22 of the top gripping portion 20 is in contact with the top surface Ra of the item R4, the side gripping portion 30 is positioned above the item R3. At this time, the lower end of the second suction portion 32 of the side gripping portion 30 is positioned a distance B above the lower end of the first suction portion 22 (see Figure 2). Therefore, the second suction portion 32 of the side gripping portion 30 does not contact the item R3. As shown in Figure 8, the gripping device 1 of this embodiment can unload the item R4 only by suction with the first suction portion 22 of the top gripping portion 20.

<Multiple piece determination process>
9 to 13 are plan views for explaining the results of the determination of whether or not multiple objects can be picked up by the gripping device. Note that Fig. 9 to Fig. 13 show multiple objects R stacked on a pallet as viewed from above in the vertical direction. In Fig. 9 to Fig. 13, the objects R are indicated by solid lines, and the first suction surface 22a of the first suction portion 22 in the upper gripping portion 20 is indicated by a two-dot chain line. That is, in Fig. 9 to Fig. 13, the area indicated by the two-dot chain line is the suction area C of the upper gripping portion 20.

Figure 9 shows multiple (12 in this embodiment) items R stacked in a "block stack". In the case of "block stacking", the suction area C of the first suction surface 22a of the first suction portion 22 in the upper gripping portion 20 is 90% of the total area of the upper surface Ra of the four items R. Therefore, if the judgment ratio is set to 70%, the upper gripping portion 20 can suction and lift four items R at a time.

Figure 10 shows multiple (12 in this embodiment) items R stacked in an "alternate row". In other words, "alternate row stacking" is achieved by wrapping the arrangement of items R shown in Figure 9 and the arrangement of items R shown in Figure 10 alternately in the vertical direction. In the case of "alternate row stacking", the suction area C of the first suction surface 22a of the first suction portion 22 in the upper gripping portion 20 is 70% of the total area of the upper surface Ra of the six items R. Therefore, when the judgment ratio is set to 70%, the upper gripping portion 20 can suction and lift six items R at a time.

11 shows a "brick stack" of multiple (five in this embodiment) items R. That is, the "brick stack" is a stack of items R arranged as shown in FIG. 11(a) and as shown in FIG. 11(b) alternately wrapped in a vertical direction. In the case of the "brick stack", the suction area C1 of the first suction surface 22a of the first suction portion 22 in the upper gripping portion 20 in each step is 80% of the total area of the upper surface Ra of the two items R. Therefore, when the judgment ratio is set to 70%, the upper gripping portion 20 can lift up two items R at one time by suctioning them. However, in the case of the "brick stack", the suction area C2 of the first suction surface 22a of the first suction portion 22 in the upper gripping portion 20 in each step is 40% of the total area of the upper surface Ra of the two items R. Therefore, when the judgment ratio is set to 70%, the upper gripping portion 20 cannot lift up two items R at one time by suctioning them.

Figure 12 shows a case where multiple (four in this embodiment) articles R are stacked in a "window stack". In the case of "window stacking", the suction area C1 of the first suction surface 22a of the first suction portion 22 in the upper gripping portion 20 is 80% of the total area of the upper surface Ra of the two articles R. Therefore, if the judgment ratio is set to 70%, the upper gripping portion 20 can pick up and lift two articles R at a time. However, in the case of "window stacking", the suction area C2 of the first suction surface 22a of the first suction portion 22 in the upper gripping portion 20 is 50% of the total area of the upper surface Ra of the two articles R. Therefore, if the judgment ratio is set to 70%, the upper gripping portion 20 cannot pick up and lift two articles R at a time.

Figure 13 shows "double pinhole stacking" of multiple (four in this embodiment) articles R. In the case of "double pinhole stacking," the suction area C of the first suction surface 22a of the first suction portion 22 in the upper gripping portion 20 is 80% of the total area of the upper surface Ra of the two articles R. Therefore, when the judgment ratio is set to 70%, the upper gripping portion 20 can suction and lift two articles R at a time.

[Effects of this embodiment]
The gripping device of the first aspect comprises an upper surface gripping unit 20 having a first adsorption surface 22a capable of adsorbing to an upper surface Ra of an item R, a judgment unit 97 that judges whether the upper surface gripping unit 20 can be adsorbed to multiple items R and raised depending on the area of the upper surface Ra of the items R and the arrangement of the items R, and a control unit 96 that controls the movement of the upper surface gripping unit 20 depending on the judgment result of the judgment unit 97.

According to the gripping device of the first aspect, the determination unit 97 determines whether the upper gripping unit 20 can be lifted by adsorbing to multiple objects R, depending on the area of the upper surface Ra of the objects R and the arrangement of the objects R. When the upper gripping unit 20 can be lifted by adsorbing to multiple objects R, the control unit 96 moves the upper gripping unit 20 to a position facing the upper surfaces Ra of the multiple objects R, and when the upper gripping unit 20 cannot be lifted by adsorbing to multiple objects R, the control unit 96 moves the upper gripping unit 20 to a position facing the upper surface Ra of a single object R. Therefore, the upper gripping unit 20 can simultaneously grip and transport multiple objects R at once as necessary, improving transport capacity.

The gripping device according to the second aspect is the gripping device according to the first aspect, and further, the determination unit 97 compares the suction area of the upper surface gripping unit 20 with the total area of the upper surface Ra of the multiple objects R, and when the suction area is equal to or greater than a preset determination ratio of the total area, determines that the upper surface gripping unit 20 can be lifted by adsorbing to the multiple objects R. This makes it easy to determine whether the upper surface gripping unit 20 can be lifted by adsorbing to the multiple objects R.

The gripping device according to the third aspect is the gripping device according to the first or second aspect, and further includes a side gripping section 30 having a second suction surface 32a capable of adsorbing to the side surface Rb of the article R, and a flip-up mechanism 60 capable of switching between a first state in which the side gripping section 30 is positioned below the lower end of the top gripping section 20 and a second state in which the side gripping section 30 is positioned above the lower end of the top gripping section 20, and the control section 96 controls the movement of the side gripping section 30 according to the determination result of the determination section 97. As a result, the top gripping section 20 and the side gripping section 30 can simultaneously grip and transport multiple articles R at once as necessary, thereby improving the transport capacity.

The gripping device according to the fourth aspect is the gripping device according to the third aspect, and further, the determination unit 97 determines that the side gripping unit 30 needs to adhere to the side Rb of the article R when the length of the perforation or zipper portion on the top surface Ra of the article R is longer than the length of one side of the top surface Ra of the article R. This makes it easy to determine whether the side gripping unit 30 can adhere to multiple articles R and lift them up.

The gripping device according to the fifth aspect is the gripping device according to the third or fourth aspect, and further, when the number of glued points on the top surface Ra of the object R is less than a preset reference number, the determination unit 97 determines that the side gripping unit 30 needs to adhere to the side surface Rb of the object R. This makes it easy to determine whether the side gripping unit 30 can adhere to multiple objects R and lift them.

The gripping method according to the sixth aspect includes a step of providing an upper gripping unit 20 having a first suction surface 22a capable of being attracted to the upper surface Ra of the object R, and determining whether the upper gripping unit 20 can be attracted to and lifted by multiple objects R according to the area of the upper surface Ra of the object R and the arrangement of the object R, and a step of controlling the movement of the upper gripping unit 20 when it is determined that the upper gripping unit 20 can be attracted to and lifted by multiple objects R. This allows the upper gripping unit 20 to simultaneously grip and transport multiple objects R at once as necessary, improving transport capacity.

Although the embodiments of the present disclosure have been described above, the embodiments are not limited to the contents of these embodiments.

For example, in this embodiment, the side gripping portion 30, the first arm 40, and the second arm 50 rotate around the rotation axis A of the flip-up mechanism 60 to move the side gripping portion 30 between a position below and a position above the lower end of the upper gripping portion 20, but this may also be achieved by translational movement in the Z-axis direction.

LIST OF SYMBOLS 1 Grip device 10 Base 10a Connection 12 Swivel shaft 14 Swivel mechanism 16 Lifting mechanism 20 Top gripping portion 20a First opposing surface 22 First suction portion 22a First suction surface 24 First suction mechanism 30 Side gripping portion 30a Second opposing surface 32 Second suction portion 32a Second suction surface 34 Second suction mechanism 40 First arm 42 First support portion 44 First telescopic mechanism 44a First fixed portion 44b First movable portion 50 Second arm 52 Second support portion 54 Second telescopic mechanism 54a Second fixed portion 54b Second movable portion 60 Flip-up mechanism 62 Fixed portion 64 Rotating portion 70 Imaging device 80 Input/output device 90 Control device 92 Communication unit 94 Memory unit 96 Control unit 97 Judgment unit 100 Management device R Article Ra Top surface Rb Side surface

Claims (6)

An upper gripping portion having a first suction surface capable of being suctioned to an upper surface of an article;
a determination unit that determines whether the upper gripping unit can be attracted to and lifted by the plurality of articles based on the area of the upper surfaces of the articles and the arrangement of the articles;
a control unit that controls movement of the upper gripping unit in response to a determination result of the determination unit;
A gripping device comprising: the determination unit compares an adsorption area of the upper gripping portion with a total area of the upper surfaces of the plurality of articles, and determines that the upper gripping portion can be adsorbed to the plurality of articles and lifted when the adsorption area is equal to or greater than a predetermined determination ratio of the total area.
The gripping device according to claim 1 . A side gripping portion having a second adsorption surface capable of adsorbing to a side surface of the article;
The device further includes a flip-up mechanism that can switch between a first state in which the side gripping portion is positioned below a lower end of the upper gripping portion and a second state in which the side gripping portion is positioned above the lower end of the upper gripping portion,
The control unit controls the movement of the side grip unit in accordance with the determination result of the determination unit.
The gripping device according to claim 1 or 2. The determination unit determines that suction to the side surface of the article by the side gripping unit is necessary when a length of a perforation or a zipper portion on the top surface of the article is longer than a length of one side of the top surface of the article.
The gripping device according to claim 3. the determination unit determines that the side surface of the article needs to be suctioned by the side gripping unit when the number of glue points on the top surface of the article is less than a preset reference number.
The gripping device according to claim 3. An upper gripping portion having a first suction surface capable of being suctioned to an upper surface of an article,
determining whether the upper gripping portion can adsorb and lift the multiple articles according to the area of the upper surfaces of the articles and the arrangement of the articles;
controlling movement of the upper gripping portion when it is determined that the upper gripping portion is capable of adsorbing to the plurality of articles and being lifted;
The gripping method has the following features.

Images