Holding device and control method of the same

Abstract

To provide a holding device which enables improvement of transport capacity, and to provide a control method of the holding device.SOLUTION: A holding device includes: a holding part having a suction surface capable of suctioning upper surfaces of one or more articles; a connection part which connects a tip of an arm of a transport device with the holding part; and a control device which sets a holding center position which is a position in a horizontal direction of the tip of the arm relative to the holding part based on a barycentric position of the articles to be held.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present invention relates to a gripping device and a method for controlling a gripping device. [Background technology]

[0002] There are known conveying devices such as palletizing devices and depalletizing devices that load articles onto pallets, unload articles from pallets, or transfer articles from one pallet to another. For example, Patent Document 1 discloses a gripping device that is an end effector of a robot arm and grips a target object at its bottom. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2021-030431 A Summary of the Invention [Problem to be solved by the invention]

[0004] Incidentally, the gripping device of Patent Document 1 has multiple (e.g., three) grippers, and is capable of not operating some of the grippers and suctioning and gripping a load using only the other grippers, and it is preferable to grip one load with one gripper without using multiple grippers. However, if the load is unevenly distributed with respect to the entire gripper, the center of gravity of the load and the gripping center position (TCP: Tool Centering Point) are misaligned, generating a moment, which increases the load on the robot arm and reduces the conveying speed.

[0005] The present disclosure is devised to solve the above-mentioned problems, and aims to provide a gripping device and a control method for a gripping device that can improve conveying capacity. [Means for solving the problem]

[0006] In order to achieve the above-mentioned objective, a gripping device according to one embodiment of the present disclosure comprises a gripping section having an adsorption surface capable of adsorbing to the upper surface of one or more articles, a connection section that connects the tip of an arm of a conveying device to the gripping section, and a control device that sets a gripping center position, which is the horizontal position of the tip of the arm relative to the gripping section, based on the center of gravity position of the article to be gripped.

[0007] In order to achieve the above-mentioned objective, a control method for a gripping device according to one embodiment of the present disclosure includes a transport target data acquisition step of acquiring transport target data including at least data on the dimensions and weight of an item to be gripped by the gripping device, an image data acquisition step of acquiring image data of a specified area including the item to be gripped, a center of gravity position calculation step of calculating the center of gravity position of the item to be gripped based on the transport target data and the image data, and a gripping center position setting step of setting the gripping center position based on the center of gravity position. Effect of the Invention

[0008] According to the present disclosure, it is possible to obtain the effect of improving the transport capacity. [Brief description of the drawings]

[0009] [Figure 1] FIG. 1 is a schematic diagram of a gripping device according to the present embodiment. [Diagram 2] FIG. 2 is a schematic diagram showing an aspect in which the gripping center position of the gripping device shown in FIG. 1 has been adjusted. [Diagram 3] FIG. 3 is a schematic block diagram of the gripping device shown in FIG. [Figure 4] FIG. 4 is a flowchart illustrating a process flow of the control device. [Diagram 5] FIG. 5 is a plan view for explaining the position of the center of gravity of an article to be grasped. [Figure 6] FIG. 6 is a plan view for explaining the position of the center of gravity of an article to be grasped.

[0010] (Embodiment) Hereinafter, the embodiments according to the present disclosure will be described in detail with reference to the drawings. Note that the present invention is not limited to these embodiments. In addition, 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 will be described, and other components will be omitted, and the same components will be given the same reference numerals, and different components will be given different reference numerals.

[0011] FIG. 1 is a schematic diagram of a gripping device according to this embodiment. FIG. 2 is a schematic diagram showing an aspect in which the gripping center position of the gripping device shown in FIG. 1 is adjusted. FIG. 3 is a schematic block diagram of the gripping device shown in FIG. 1. The gripping device 1 shown in FIGS. 1 to 3 is a device that is attached to the tip of an arm RA of 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 gripping device 1 can simultaneously grip and convey multiple articles R whose upper surfaces are located on the same horizontal plane.

[0012] Here, the definition of a pallet by the Japan Pallet Association is "a surface on which cargo is placed in a single unit, and has a structure that allows loading, transporting, and storage all by hand or by a dedicated vehicle such as a forklift, including those with a superstructure." In this embodiment, a pallet refers to a container or platform on which the goods R are loaded. In other words, the pallet referred to here is not limited to a so-called flat platform, but may also include a basket cart or the like, and may be of any shape. The goods R are loaded onto the pallet, such as goods to be shipped. The goods R are also referred to as cardboard boxes in which goods are packed. The goods R have at least a flat top surface, and in this embodiment, a rectangular cardboard box is assumed.

[0013] 1 to 3, the gripping device 1 includes a base 10, a connection unit 20, an adjustment mechanism 30, and a gripping unit 40. 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. In this embodiment, the gripping device 1 including the imaging device 70, the input / output device 80, and the control device 90 includes a mode in which the functions of each of the devices 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.

[0014] In this embodiment, the X-axis direction is a direction parallel to the suction surfaces (first suction surface 42a and second suction surface 44a) of the gripping device 1 that grip the top surface of the article R, the Y-axis direction is a direction parallel to the suction surfaces (first suction surface 42a and second suction surface 44a) of the gripping device 1 that grip the top surface of the article R and perpendicular to the X-axis direction, and the Z-direction is a direction perpendicular to the X-axis and Y-axis directions. At least during operation of the gripping device 1, the X-axis and Y-axis directions correspond to the horizontal direction, and the Z direction corresponds to the vertical direction.

[0015] 1 and 2 is connected to a tip of an arm RA of a palletizing device to which the gripping device 1 is attached via a connection part 20. The connection part 20 connects the tip of the arm RA of the palletizing device to which the gripping device 1 is attached to the base part 10 so as to be relatively movable in the X and Y directions. The connection part 20 connects the tip of the arm RA to a gripping part 40 via the base part 10. Note that in the example shown in FIGS. 1 and 2, only a configuration that is relatively movable in the X direction is shown, and a configuration that is relatively movable in the Y direction is omitted. The connection part 20 has a linear guide part 22, a movable connection part 24, and a coupling part 26.

[0016] The linear motion guide portion 22 guides linear motion of the movable connection portion 24 in the X direction relative to the base portion 10. The linear motion guide portion 22 is realized, for example, by a linear guide fixed to the upper surface of the base portion 10, or a groove or rail formed on the upper surface side of the base portion 10. In the example shown in Figs. 1 and 2, the linear motion guide portion 22 supports the lower end portion of the movable connection portion 24 and regulates linear motion of the movable connection portion 24 in the Y direction and the Z direction relative to the base portion 10. In addition, the linear motion guide portion 22 regulates rotational motion of the movable connection portion 24 relative to the base portion 10.

[0017] The movable connection part 24 is supported at its lower end so as to be linearly movable in the X direction relative to the linear guide part 22. The movable connection part 24 moves linearly in the X direction relative to the linear guide part 22 between directly above the center of a gripping part 40 (described below) and directly above the center of a second suction part 44 by an adjustment mechanism 30. A connecting part 26 is fixed to the upper end of the movable connection part 24. The connecting part 26 is connected to the tip of an arm RA of a palletizing device to which the gripping device 1 is attached.

[0018] For example, if the palletizing device to which the gripping device 1 is attached is a multi-joint robot, the cooperative operation of multiple axes of the multi-joint robot realizes the lifting and lowering movement of the gripping device 1 in the Z direction and the rotational movement about the Z axis via the tip of the arm RA. For example, if the palletizing device to which the gripping device 1 is attached is a Cartesian coordinate robot, the lifting and lowering movement of the gripping device 1 in the Z direction is realized via the tip of the arm RA by the operation of the vertical translatory joint of the Cartesian coordinate robot.

[0019] The adjustment mechanism 30 linearly moves the base 10 and the gripping part 40 in the X direction relative to the connecting part 26 and the arm RA via the movable connecting part 24. In other words, the adjustment mechanism 30 adjusts the position of the gripping part 40 in the X direction relative to the arm RA. The adjustment mechanism 30 is realized by a known mechanism such as a linear actuator including a motor or an air cylinder, or a rack and pinion mechanism. In this embodiment, the adjustment mechanism 30 has a fixed part 32, a movable part 34, and an adjustment drive part 36 (see FIG. 3). The fixed part 32 is fixed to the base 10. The fixed part 32 supports the movable part 34 so that the movable part 34 can move linearly in the X direction within a predetermined range. The movable part 34 can move in the X direction relative to the fixed part 32. The movable part 34 is fixed to the movable connecting part 24.

[0020] For example, when the adjustment mechanism 30 includes an air cylinder, the fixed part 32 is a cylinder, the movable part 34 is a rod, and the adjustment drive part 36 is an air supply mechanism. The adjustment mechanism 30 has a locking mechanism (not shown) that can determine the horizontal position of the gripping part 40 relative to the arm RA by determining the position of the movable part 34 in the X direction relative to the fixed part 32. 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.

[0021] 1 and 2 show the connection part 20 and the adjustment mechanism 30 that can relatively move the base part 10 and the tip of the arm RA in the X direction, but the connection part 20 and the adjustment mechanism 30 of the present invention may be provided to relatively move the base part 10 and the tip of the arm RA in the X direction and the Y direction. For example, the linking part 26 may be provided to be relatively movable in the Y direction with respect to the movable connection part 24, and the second adjustment mechanism 30 may be provided to linearly move the linking part 26 with respect to the movable connection part 24. In other words, the adjustment mechanism 30 adjusts the horizontal position of the grip part 40 with respect to the arm RA.

[0022] The gripping part 40 is provided on the lower part of the base 10. The gripping part 40 has an opposing surface 40a on its lower surface that faces the upper surface of the article R. The gripping part 40 is fixed to the base 10 so that the opposing surface 40a is perpendicular to the Z direction. The gripping part 40 moves up and down and rotates in accordance with the lifting and rotating movements of the base 10 and the connection part 20. The gripping part 40 has a plurality of suction parts on the opposing surface 40a that can suction the article R.

[0023] The plurality of suction portions are arranged in line in the X direction, and in the example shown in Fig. 1 and Fig. 2, there are two suction portions, a first suction portion 42 and a second suction portion 44, but in the present invention, there may be three or more suction portions. The plurality of suction portions may also be arranged in line in the X direction and the Y direction. In the example shown in Fig. 1 and Fig. 2, the first suction portion 42 and the second suction portion 44 are each depicted as a single block shape, but may be, for example, a plurality of suction pads protruding downward from the opposing surface 40a of the gripping portion 40.

[0024] The first suction unit 42 has a first suction surface 42a at a lower end, which is an end opposite to the opposing surface 40a. When the first suction surface 42a is in contact with the upper surface of the article R, the first suction unit 42 is suctioned to the upper surface of the article R by the operation of a first suction mechanism 46 shown in FIG. 3. The first suction mechanism 46 includes, for example, a vacuum generator that is connected to the first suction surface 42a via an air pipe (not shown) and sucks air from the first suction surface 42a. For example, when the first suction unit 42 is composed of a plurality of suction pads, each suction pad is connected to the first suction mechanism 46, which is a vacuum generator, via an air pipe. The operation of the first suction mechanism 46 is controlled by a control unit 96 of the control device 90.

[0025] The second suction portion 44 has a second suction surface 44a at the lower end, which is the end opposite to the opposing surface 40a. When the second suction surface 44a is in contact with the side surface of the article R, the second suction mechanism 48 shown in FIG. 3 is activated, so that the second suction portion 44 adheres to the side surface of the article R with the second suction surface 44a. The second suction mechanism 48 includes, for example, a vacuum generator that is connected to the second suction surface 44a via an air pipe (not shown) and sucks air from the second suction surface 44a. For example, when the second suction portion 44 is composed of a plurality of suction pads, each suction pad is connected to the second suction mechanism 48, which is a vacuum generator, via an air pipe. The operation of the second suction mechanism 48 is controlled by the control unit 96 of the control device 90.

[0026] The gripping device 1 includes a plurality of suction mechanisms (first suction mechanism 46 and second suction mechanism 48) that respectively operate to suction the suction surface (first suction surface 42a and second suction surface 44a) that is divided into a plurality of regions. For example, as shown in FIG. 1, two articles R may be gripped by the first suction portion 42 and the second suction portion 44, respectively. Also, for example, as shown in FIG. 2, one article R may be gripped by the second suction portion 44. At this time, suction on the first suction surface 42a of the first suction portion 42 can be stopped by stopping the first suction mechanism 46.

[0027] The imaging device 70 captures images of a pallet on which the article R is to be loaded or unloaded, the article R loaded on the pallet, and the stacked arrangement of the articles R, and outputs image data that can identify the position and individual objects of the imaged objects to the control device 90. The imaging device 70 is disposed in a position where the pallet and the article R loaded on the pallet can be observed. The imaging device 70 includes one or more cameras.

[0028] The input / output device 80 includes an input device through which an operator inputs various pieces of information for operating the gripping device 1, and an output device for presenting various pieces of information to the operator. The input device is realized by, for example, a keyboard, a mouse, a physical switch, a button, a touch panel, or the like. The output device is realized by, for example, a display device including a liquid crystal display device, an organic EL (Electro Luminescence) display device, or the like, a light-emitting device including an LED (Light Emitting Diode), or a speaker, or the like. The input / output device 80 may be an information terminal capable of inputting and outputting various pieces of information.

[0029] 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, and a control unit 96. 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 acquired 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 an HDD (Hard Disk Drive).

[0030] The control unit 96 is an arithmetic processing device, and includes 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.

[0031] 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, dimensions, perforations of boxes, number of glued items, number of items R, arrangement of each item R on the pallet or the position where the items R are stacked on the pallet, the order in which the items R are unloaded from the pallet or the order in which they are stacked 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.

[0032] The control unit 96 calculates the position of the center of gravity G of the article R to be gripped based on the image data and the transport target data. The control unit 96 sets the gripping center position TCP (the horizontal position of the tip of the arm RA) based on the calculated position of the center of gravity G. The control unit 96 controls the adjustment drive unit 36 ​​to adjust the horizontal position of the gripping center position TCP. The control unit 96 operates at least one of the first suction mechanism 46 and the second suction mechanism 48 to cause the gripper 40 to suck and grip the article R. The control unit 96 executes control for moving the gripping device 1 itself in the palletizing device to which the gripping device 1 is attached. When the palletizing device is a multi-joint robot, the movement of the gripping device 1 itself is realized by the cooperative operation of multiple axes of the multi-joint robot.

[0033] 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 warehouse control system (WCS) or a warehouse management system (WMS), 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 in the facility in which the gripping device 1 is deployed, or may be installed at a location remote from the facility to manage the facility from the remote location.

[0034] (Control unit processing) Next, a process flow for adjusting the gripping center position TCP 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. 4 is a flowchart illustrating the process flow of the control device. The process shown in FIG. 4 is executed by the control unit 96 of the control device 90 based on programs and data pre-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 proceeds to step S10 shown in FIG. 4 to start the process.

[0035] 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 on the dimensions and weight of each item R to be grasped.

[0036] The control device 90 acquires captured image data (step S12). In this embodiment, the control device 90 causes the imaging device 70 to capture an image of a predetermined area including the object R to be grasped. 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 installed, for example. The control device 90 performs image processing on the captured image data to recognize the position, shape, dimensions, etc. of the object R to be grasped.

[0037] The control device 90 calculates the position of the center of gravity G of the object R to be grasped (step S14). The control device 90 identifies the position of the center of gravity G of the object R to be grasped based on the position, shape, and dimensions of the object R to be grasped extracted based on the captured image data acquired in step S12. The gripping device 1 is capable of grasping multiple objects R at once if the height dimensions of the objects R are the same. When grasping multiple objects R at once, the control device 90 calculates the position of the combined center of gravity of the multiple objects R to be grasped based on the positions of the centers of gravity G of all the objects R to be grasped and the weight data of the objects R included in the transport object data acquired in step S10.

[0038] The control device 90 sets the gripping center position TCP (step S16). More specifically, the control device 90 sets the gripping center position TCP corresponding to the tip of the arm RA based on the position of the center of gravity G of the article R to be gripped calculated in step S14, and sets the amount of movement adjustment by the adjustment mechanism 30 for positioning the movable connection part 24 at a position corresponding to the gripping center position TCP.

[0039] For example, as shown in FIG. 1, when two articles R of the same size and weight are gripped by the first suction portion 42 and the second suction portion 44, the combined center of gravity of the two articles R is located directly below the center of the gripping portion 40. In this case, for example, the gripping center position TCP is set directly above the combined center of gravity, and a movement adjustment amount is set so that the X-direction position of the movable connection portion 24 is located directly above the center of the gripping portion 40. Also, as shown in FIG. 2, when one article R is gripped by the second suction portion 44, the center of gravity G of the article R is located directly below the center of the second suction portion 44. In this case, the gripping center position TCP is set directly above the center of gravity G, and a movement adjustment amount is set so that the X-direction position of the movable connection portion 24 is located directly above the center of the second suction portion 44.

[0040] The control device 90 adjusts the gripping center position TCP and grips the article R to be gripped (step S18). The control device 90 first controls the arm RA to move and rotate the gripping device 1 to a position where the upper surface of the article R to be gripped faces the area of ​​the first suction surface 42a and the second suction surface 44a that grips the article R. The control device 90 then controls the adjustment drive unit 36 ​​to move the movable connection part 24 in the X direction along the linear guide part 22 by the movement adjustment amount set in step S16, thereby adjusting the gripping center position TCP.

[0041] The control device 90 then lowers the gripping device 1 to bring the top surface of the article R to be gripped into contact with the areas of the first suction surface 42a and the second suction surface 44a that grip the article R. The control device 90 then activates at least one of the first suction mechanism 46 and the second suction mechanism 48 to cause the top surface of the article R to be suctioned to at least one of the first suction surface 42a and the second suction surface 44a. This causes the gripping device 1 to grip the article R with the gripping portion 40.

[0042] The control device 90 transports (unloads) the article R (step S20). The control device 90 controls the arm RA to raise the gripping device 1 gripping the article R, transports it to a predetermined position, and unloads the article R from the pallet. The control device 90 repeatedly executes the processes from step S10 to step S20 shown in Fig. 4 until, for example, all of the articles R are unloaded from the pallet.

[0043] In the process of this embodiment shown in FIG. 4, step S12 has been described as being performed for each transport, but for example, when the items R are arranged in a plane on the pallet, that is, when multiple items R are not stacked vertically, step S12 of imaging all the items R on the pallet may be performed only once at the beginning. Similarly, step S10 may also be performed by first acquiring transport target data for all the items R stacked on the pallet. In addition, although the above description has been given of the process for unloading the items R from a pallet on which multiple items R are stacked, the process of this embodiment shown in FIG. 4 can also be applied to the case of stacking multiple items R on a pallet or transferring items from a pallet to another pallet.

[0044] In the above, the gripping center position TCP is adjusted only in the X direction, but if the adjustment mechanism 30 of the gripping device 1 allows adjustment in the Y direction as well, the gripping center position TCP may also be adjusted in the Y direction based on the Y-direction position of the center of gravity G of the object R to be gripped. In addition, if there is a deviation in the center of gravity position of the gripping device 1 itself with respect to the suction surfaces (first suction surface 42a and second suction surface 44a), it is preferable to set the gripping center position TCP based on the composite center of gravity of the gripping device 1 and the center of gravity G of the object R to be gripped, rather than the center of gravity G (composite center of gravity) of only the object R to be gripped.

[0045] (How to calculate the center of gravity) A method for calculating the position of the center of gravity G of multiple objects R to be grasped will be described below. When multiple objects R are to be grasped at once, it is necessary that the heights of the upper surfaces of the multiple objects R are the same.

[0046] A method for calculating a composite center of gravity G when two objects R1 and R2 are aligned in only one direction in a plan view and their respective centers of gravity G1 and G2 are on the same straight line will be described. FIG. 5 is a plan view that illustrates the center of gravity position of an object to be grasped. In the example shown in FIG. 5, the center of gravity G1 of the object R1 and the center of gravity G2 of the object R2 are aligned in the X direction in a plan view. If the weight of the object R1 is m1, the weight of the object R2 is m2, the distance between the composite center of gravity G of the two objects R1 and R2 and the center of gravity G1 is L1, the distance between the center of gravity G and the center of gravity G2 is L2, and the distance between the center of gravity G1 and the center of gravity G2 is L, the distances L1 and L2 are expressed by the formulas (1) and (2).

[0047]

number

[0048]

number

[0049] Next, a method for calculating a composite center of gravity G will be described, which is not limited to the example shown in FIG. 5 and can be applied even when the centers of gravity G1, G2, and G3 of multiple items R1, R2, and R3 are not on the same line. FIG. 6 is a plan view that illustrates the position of the center of gravity of an item to be grasped. In the example shown in FIG. 6, the center of gravity G1 of item R1, the center of gravity G2 of item R2, and the center of gravity G3 of item R3 are not on the same line in a plan view. Also, the coordinates of the center of gravity G1 of item R1 are (x G1 , y G1 ), and the coordinates of the center of gravity G2 of the item R2 are (x G2 , y G2 ), and the coordinates of the center of gravity G3 of the item R3 are (x G3 , y G3 ) The number of items is n, and the weights of the n items R1, . . ., Ri, . . ., Rn are m1, . . ., m i , , m n Then, the coordinates of the combined center of gravity G of n items R1, . . ., Ri, . . ., Rn (x G , y G ) is shown by equations (3) and (4).

[0050]

number

[0051]

number

[0052] (Effects of the embodiment) The gripping device 1 and the control method of the gripping device 1 described in the embodiment can be understood, for example, as follows.

[0053] The gripping device 1 of the first embodiment comprises a gripping unit 40 having suction surfaces (first suction surface 42a and second suction surface 44a) capable of being adsorbed to the upper surface of one or more articles R, a connection unit 20 that connects the tip of an arm RA of a conveying device to the gripping unit 40, and a control device 90 that sets a gripping center position TCP, which is the horizontal position of the tip of the arm RA relative to the gripping unit 40, based on the position of the center of gravity G of the article R to be gripped.

[0054] The gripping device 1 according to the first embodiment can set the gripping center position TCP based on the position of the center of gravity G of the article R to be gripped, and therefore can adjust the gripping center position TCP to a suitable position even when gripping articles R of various sizes and numbers all at once. Therefore, the moment load due to the center of gravity G of the article R to be gripped relative to the gripping center position TCP can be suppressed. This reduces the load on the gripping device 1 and mechanical parts such as bearings and sliding parts of the conveying device to which the gripping device 1 is attached, and also improves the maximum conveying speed by reducing load shaking, thereby improving the conveying capacity.

[0055] In the gripping device 1 of the second embodiment, the control device 90 calculates the combined center of gravity G position of all items R to be gripped based on transport object data that includes at least dimensional and weight data of all items R to be gripped, and image data capturing an image of a specified area including all items R to be gripped.

[0056] The gripping device 1 according to the second embodiment calculates the position of the center of gravity G of the object R to be gripped for setting the gripping center position TCP based on the transport object data and the captured image data. The transport object data can be included in the order data handled in the transport system, so this can be realized without the need to build a new system. Similarly, the imaging device 70 that captures the captured image can use, for example, an imaging device for monitoring or the like that is installed in the transport system, so this can be realized without the need for a new device.

[0057] In the gripping device 1 of the third embodiment, the connection portion 20 connects the tip of the arm RA and the gripping portion 40 so that they can move horizontally relative to each other, and the gripping device 1 further includes an adjustment mechanism 30 that moves the gripping portion 40 horizontally relative to the tip of the arm RA, and the control device 90 controls the adjustment mechanism 30 based on the set gripping center position TCP.

[0058] The gripping device 1 according to the third embodiment can set the gripping center position TCP based on the position of the center of gravity G of the article R to be gripped, and can automatically move the gripping unit 40 in the horizontal direction so that the set gripping center position TCP coincides with the tip of the arm RA. This makes it possible to adjust the gripping center position TCP to a suitable position each time, even when gripping and transporting various articles R one after another. Therefore, the moment load caused by the center of gravity G of the article R to be gripped relative to the gripping center position TCP can be constantly suppressed, and transport capacity can be improved.

[0059] In the gripping device 1 of the fourth aspect, the connection part 20 connects the tip of the arm RA and the gripping part 40 so as to be movable relative to one another in one horizontal direction (X direction), and the gripping device 1 further includes an adjustment mechanism 30 that moves the gripping part 40 in one direction (X direction) relative to the tip of the arm RA, and the control device 90 controls the adjustment mechanism 30 based on the set gripping center position TCP.

[0060] The gripping device 1 according to the fourth embodiment can set the gripping center position TCP based on the position of the center of gravity G of the article R to be gripped, and can automatically move the gripping unit 40 in one direction (X direction) so that the set gripping center position TCP coincides with the tip of the arm RA. This makes it possible to adjust the gripping center position TCP to a suitable position each time, even when gripping and transporting various articles R one after another. Therefore, the moment load caused by the center of gravity G of the article R to be gripped relative to the gripping center position TCP can be constantly suppressed, and transport capacity can be improved.

[0061] In the gripping device 1 of the fifth aspect, the suction surface includes an suction surface divided into multiple regions (first suction surface 42a and second suction surface 44a), and the gripping device 1 further includes multiple suction mechanisms (first suction mechanism 46 and second suction mechanism 48) that each activate suction on the suction surface when the suction surface is in contact with the upper surface of the article R.

[0062] The gripping device 1 of the fifth aspect can activate the suction of each area of ​​the suction surface using multiple suction mechanisms, and therefore can stop suction of parts of the suction surface that are not in contact with the article R.

[0063] The gripping device 1 according to the sixth embodiment has a locking mechanism for determining the horizontal position of the gripping portion 40 relative to the arm RA.

[0064] The gripping device 1 according to the sixth aspect can fix the horizontal position of the gripping part 40 relative to the arm RA when gripping and transporting the article R with the gripping part 40, and therefore can prevent the position of the gripping part 40 relative to the arm RA from shifting during transport, and the central position TCP from shifting from the position of the center of gravity G. This allows the article to be transported stably.

[0065] The control method of the gripping device 1 in the seventh aspect is a control method of the gripping device 1 in any one of the first to sixth aspects, and includes a transport target data acquisition step (step S10) of acquiring transport target data including at least dimensional and weight data of the item R to be gripped by the gripping device 1, an image data acquisition step (step S12) of acquiring image data of a specified area including the item R to be gripped, a center of gravity position calculation step (step S14) of calculating the center of gravity G position of the item R to be gripped based on the transport target data and the image data, and a gripping center position setting step (step S16) of setting the gripping center position TCP based on the center of gravity G position.

[0066] The control method of the gripping device 1 according to the seventh aspect can calculate the position of the center of gravity G based on the dimensions and weight of the article R to be gripped and the arrangement of the article R based on the captured image data, and set the gripping central position TCP based on the position of the center of gravity G. This allows the gripping central position TCP to be adjusted to a suitable position, thereby suppressing the moment load due to the center of gravity G of the article R to be gripped relative to the gripping central position TCP. Therefore, the load on the gripping device 1 and mechanical parts such as bearings and sliding parts of the conveying device to which the gripping device 1 is attached is reduced, and the maximum conveying speed can be improved by reducing load shaking, thereby improving the conveying capacity.

[0067] The control method of the gripping device 1 in the eighth aspect further includes an adjustment gripping step (step S18) in which the gripping portion 40 is moved horizontally relative to the tip of the arm RA so that the tip of the arm RA coincides with the set gripping center position TCP, and the article R is gripped by the suction surface (first suction surface 42a and second suction surface 44a) of the gripping portion 40, and a transport step (step S20) in which the article R is transported in a gripped state.

[0068] The control method of the gripping device 1 according to the eighth aspect can automatically move the gripping part 40 in the horizontal direction so that the set gripping center position TCP coincides with the tip of the arm RA. This makes it possible to adjust the gripping center position TCP to a suitable position each time, even when various articles R are gripped and transported one after another. Therefore, the moment load due to the center of gravity G of the article R to be gripped relative to the gripping center position TCP can be constantly suppressed, and the transport capacity can be improved.

[0069] Although the embodiments of the present disclosure have been described above, the embodiments are not limited to the contents of the description of these embodiments. [Explanation of symbols]

[0070] 1 Gripping device 10 base 20 Connection 22 Linear guide section 24 Movable joint 26 Connecting part 30 Adjustment mechanism 32 Fixed part 34 Moving parts 36 Adjustment drive unit 40 Gripping part 40a Opposite surface 42 1st suction part 42a 1st suction surface 44 2nd suction part 44a 2nd suction surface 46 1st suction mechanism 48 Second suction mechanism 70 Imaging Device 80 I / O Devices 90 Control device 92 Communications Department 94 Memory section 96 Control Unit 100 Management device RA Arm R, R1, R2, R3 Goods G, G1, G2, G3 Center of gravity L, L1, L2 distance

Claims

1. A gripping portion having an adsorption surface capable of adsorbing to an upper surface of one or more articles; a connection portion that connects a tip of an arm of a transport device and the gripping portion; a control device that sets a gripping center position, which is a horizontal position of the tip of the arm relative to the gripping unit, based on a center of gravity position of an article to be gripped; A gripping device comprising:

2. The control device calculates a combined center of gravity position of all the objects to be grasped based on transport object data including at least data on dimensions and weights of all the objects to be grasped and image data obtained by imaging a predetermined area including all the objects to be grasped. The gripping device according to claim 1 .

3. the connecting portion connects the tip of the arm and the gripping portion so as to be relatively movable in a horizontal direction; The gripping portion is further provided with an adjustment mechanism for horizontally moving the gripping portion relative to the tip of the arm, The control device controls the adjustment mechanism based on the set grip center position. The gripping device according to claim 1 .

4. the connecting portion connects the tip of the arm and the gripping portion so as to be relatively movable in one horizontal direction, The gripping portion may be moved in the one direction relative to the tip of the arm. The control device controls the adjustment mechanism based on the set grip center position. The gripping device according to claim 1 .

5. The adsorption surface includes an adsorption surface divided into a plurality of regions, The apparatus further includes a plurality of suction mechanisms each of which activates suction on the suction surface when the suction surface is in contact with the upper surface of the article. The gripping device according to claim 1 .

6. A lock mechanism is provided for determining the horizontal position of the gripping portion relative to the arm. The gripping device according to claim 1 .

7. A method for controlling a gripping device according to any one of claims 1 to 6, comprising the steps of: a transport object data acquisition step of acquiring transport object data including at least data on dimensions and weight of an object to be gripped by the gripping device; A captured image data acquisition step of acquiring captured image data of a predetermined area including an article to be grasped; a center of gravity position calculation step of calculating a center of gravity position of an object to be grasped based on the transport object data and the captured image data; a gripping center position setting step of setting the gripping center position based on the center of gravity position; A method for controlling a gripping device, comprising:

8. an adjustment gripping step of gripping the article with the suction surface of the gripping part in a state in which the gripping part is moved in a horizontal direction relative to the tip of the arm so that the tip of the arm coincides with the set gripping center position; a conveying step of conveying the article in a gripped state; The method of claim 7 further comprising:

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