Holding system and control device

Abstract

To provide a holding system capable of shortening a time during which the holding system holds and releases an object.SOLUTION: A holding system (gripping system 1) includes a plurality of robots 10 for holding and releasing a part of an object T, and a control device 50 for controlling the operation of the plurality of robots 10, wherein the control device 50 makes each of the plurality of robots 10 hold a part of the object T (step S11), and makes a first robot holding a first object in which a weight value most rapidly falls within a predetermined range among the plurality of robots 10 release the first object (steps S13 and S14).SELECTED DRAWING: Figure 7

Description

Technical Field

[0001] The present invention relates to a holding system and a control device.

Background Art

[0002] Conventionally, a holding system including a robot for holding an object is known. For example, Patent Document 1 (Claim 9, etc.) discloses a gripping system that includes a robot for gripping an object, and when the object gripped by the robot does not conform to a specified amount, corrects the depth at which the physical quantity of the object is estimated to reach a predetermined amount, and inserts the gripping member of the robot to the corrected depth to grip the object again.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] In the above-described conventional holding system, there is a possibility that it may take time to hold an object of a target amount. For example, in Patent Document 1 above, until the object gripped by the robot conforms to a specified amount, the gripping member of the robot is inserted to the corrected depth to grip the object again, so there is a possibility that it may take time to grip an object of a target amount. Thus, in the holding system, it is desired to shorten the time for holding and releasing the object.

[0005] The present invention has been made by the inventors of the present application newly focusing on the above problems, and an object thereof is to provide a holding system and a control device capable of shortening the time for holding and releasing an object.

Means for Solving the Problems

[0006] A holding system according to an aspect of the present invention includes a plurality of robots that hold and release a part of an object, and a control device that controls the operations of the plurality of robots. The control device causes each of the plurality of robots to hold a part of the object, and causes a first robot that holds a first object whose weight value first falls within a predetermined range among the plurality of robots to release the first object.

[0007] A control device according to an aspect of the present invention is a control device that controls the operations of a plurality of robots that hold and release a part of an object. The control device causes each of the plurality of robots to hold a part of the object, and causes a first robot that holds a first object whose weight value first falls within a predetermined range among the plurality of robots to release the first object.

Advantages of the Invention

[0008] According to the holding system and the like in the present invention, it is possible to shorten the time for holding and releasing an object.

Brief Description of the Drawings

[0009]

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Embodiments for Carrying Out the Invention

[0010] A holding system according to an aspect of the present invention includes a plurality of robots that hold and release a part of an object, and a control device that controls the operations of the plurality of robots. The control device causes each of the plurality of robots to hold a part of the object, and releases the first object held by the first robot that first holds the first object whose weight value has fallen within a predetermined range among the plurality of robots.

[0011] According to this, in the holding system, the control device causes each of the plurality of robots to hold a part of the object, and releases the first object held by the first robot that first holds the first object whose weight value has fallen within a predetermined range. In this way, by causing the plurality of robots to compete to hold an object with a weight value within a predetermined range, the object with a weight value within a predetermined range can be held and released in a shorter time. Therefore, according to the holding system, it is possible to shorten the time for holding and releasing the object.

[0012] The control device may not release the second object held by a second robot different from the first robot until the first robot releases the first object.

[0013] If the first robot cannot release the first object, for example, due to a malfunction in the first robot, it will take time to cause other robots to hold the object again and then release it. For this reason, the control device does not release the second object held by the second robot until the first robot releases the first object. Thereby, even when the first robot cannot release the first object, for example, due to a malfunction in the first robot, the second robot can release the second object held by it. Therefore, according to the holding system, it is possible to shorten the time for holding and releasing the object.

[0014] The control device may release the second object held by a second robot different from the first robot and cause the second robot to hold a part of the object again.

[0015] According to this, the control device can cause the second robot to release the second object and hold a part of the object again, so that the second robot, which was slower than the first robot, can be prepared to release the object into the next container. As a result, according to the holding system, the object can be released into the next container earlier, so that the time for holding and releasing the object can be shortened.

[0016] The control device may cause the second robot that holds the second object whose weight value is outside the predetermined range to release the second object at the position where it holds the second object. After the second object is released at the held position, the depth from the surface of the object where the weight value of the second object is estimated to be within the predetermined range is corrected, and the second robot is inserted to the corrected depth to hold again at least a part of the released second object, including a part of the object.

[0017] According to this, the control device can cause the second robot that holds the second object whose weight value is outside the predetermined range to hold a part of the object again, so that the second robot can be prepared to release the object into the next container. As a result, according to the holding system, the object can be released into the next container earlier, so that the time for holding and releasing the object can be shortened. The control device can suppress the occurrence of unevenness on the surface of the object by causing the second robot to release the second object at the position where it holds the second object and hold again at least a part of the released second object, including a part of the object. The control device can correct the depth from the surface of the object, insert the second robot to the corrected depth, and hold again a part of the object by the second robot, so that an appropriate amount of the object can be held again.

[0018] When the control device determines that the weight value of the first object is smaller than the first predetermined value, the control device may cause any of the plurality of robots to hold a part of the object, and cause the third robot that holds the third object whose weight value has become the difference between the weight value of the first object and the first predetermined value earliest among the plurality of robots to release the third object.

[0019] According to this, when the control device determines that the weight value of the first object is smaller than the first predetermined value, the control device causes the third robot that holds the third object whose weight value has become the difference between the weight value of the first object and the first predetermined value earliest to release the third object. Thereby, even when the weight value of the first object is within a predetermined range but smaller than a more preferable value (equal to or greater than the first predetermined value), the weight value of the first object can be corrected to be equal to or greater than the first predetermined value in a shorter time. Therefore, according to the holding system, it is possible to shorten the time for holding and releasing the object.

[0020] When the control device determines that the weight value of the first object is greater than the second predetermined value, the control device may cause any one of the plurality of robots to hold a part of the first object, and cause the fourth robot that holds the fourth object whose weight value has become the difference between the weight value of the first object and the second predetermined value earliest among the plurality of robots to release the fourth object at a position different from the first object.

[0021] According to this, when the control device determines that the weight value of the first object is greater than the second predetermined value, the control device causes the fourth robot that holds the fourth object whose weight value has become the difference between the weight value of the first object and the second predetermined value earliest to release the fourth object at a position different from the first object. Thereby, even when the weight value of the first object is within a predetermined range but greater than a more preferable value (equal to or less than the second predetermined value), the weight value of the first object can be corrected to be equal to or less than the second predetermined value in a shorter time. Therefore, according to the holding system, it is possible to shorten the time for holding and releasing the object.

[0022] The control device may cause one of the plurality of robots to hold an object located in the first region, cause another robot to hold an object located in the second region, and cause the one robot to hold the object located in the second region under a predetermined condition.

[0023] According to this, under predetermined conditions, the control device causes a robot that holds an object located in the first area to hold an object located in the second area. For example, when the robot holds a large number of objects in the first area and the number of objects in the first area decreases, the control device causes the robot to hold the object in the second area. Thereby, the control device can cause the robot to hold the objects relatively evenly. Or, when the robot cannot hold the object in the first area well but can hold the object in the second area, the control device causes the robot to hold the object in the second area. Thereby, the control device can cause the robot to hold the objects efficiently.

[0024] The control device may cause one of the plurality of robots to hold an object located in the first area, cause other robots to hold objects located in the second area, and cause the one robot to hold an object located at a boundary portion between the first area and the second area under predetermined conditions.

[0025] According to this, under predetermined conditions, the control device causes a robot that holds an object located in the first area to hold an object located at a boundary portion between the first area and the second area. For example, since the objects at the boundary portion between the first area and the second area often remain without being held, when the robot holds a large number of objects in the first area and the number of objects in the first area decreases, the control device causes the robot to hold the object at the boundary portion. Thereby, the control device can cause the robot to hold the objects relatively evenly. Or, when the robot cannot hold the object in the first area well but can hold the object at the boundary portion, the control device causes the robot to hold the object at the boundary portion. Thereby, the control device can cause the robot to hold the objects efficiently.

[0026] The control device may detect the amount of the objects remaining in the first area and the amount of the objects remaining in the second area.

[0027] According to this, the control device can determine which area's object the robot should hold by detecting the amount of the object remaining in the first area and the amount of the object remaining in the second area. Thereby, the control device can cause the robot to hold the objects relatively evenly or cause the robot to hold the objects efficiently.

[0028] A control device according to an aspect of the present invention is a control device that controls the operations of a plurality of robots that hold and release a part of an object, causes each of the plurality of robots to hold a part of the object, and releases the first object held by the first robot that first held the first object whose weight value first fell within a predetermined range among the plurality of robots.

[0029] According to this, the control device causes each of the plurality of robots to hold a part of the object, and releases the first object held by the first robot that first held the first object whose weight value first fell within a predetermined range. Thereby, also in the control device, similar to the holding system, it is possible to shorten the time for holding and releasing the object.

[0030] The present invention can be realized not only as such a holding system and control device, but also as a holding method or control method including characteristic processing steps performed by the holding system or control device. The present invention can be realized as a program for causing a computer to execute the holding method or control method, or as a recording medium such as a computer-readable CD-ROM (Compact Disc-Read Only Memory) on which the program is recorded. And such a program can be distributed via a recording medium such as a CD-ROM and a transmission medium such as the Internet. The present invention can also be realized as an integrated circuit including a processing unit that performs the holding method or control method.

[0031] Hereinafter, with reference to the drawings, a holding system and a control device according to embodiments (including modifications thereof) of the present invention will be described. Each of the embodiments described below shows comprehensive or specific examples. The numerical values, shapes, materials, components, arrangement positions and connection forms of the components, each step in the method, the order of the steps, etc. shown in the following embodiments are merely examples and are not intended to limit the present invention. In each figure, the dimensions and the like are not shown precisely. In each figure, the same or similar components are denoted by the same reference numerals.

[0032] In the following description and drawings, as a holding system and a holding method for holding and releasing a part of an object, a gripping system 1 and a gripping method for gripping and releasing a part of an object will be described as an example. However, the holding in the holding system and the holding method is not limited to gripping. That is, in the holding system and the holding method, the object may be held by suction, the object may be scooped up and held, the object may be stabbed and held, or the object may be held by any other method. Thus, the gripping system 1 and the gripping method described below are examples of the holding system and the holding method, and the gripping members (in the following embodiments, the gripping members 100, 100a, 100b, 101, 101a, 101b, 102, 102a, 102b) provided in the gripping system 1 are examples of the holding members provided in the holding system. That is, the holding system may be provided with a holding member configured to hold the object by suction, scoop up the object and hold it, stab the object and hold it, etc., instead of the gripping member 100 or the like described later. In addition, the places described as "gripping" below can be appropriately read as "holding".

[0033] (Embodiment) [1 General description of the gripping system 1] First, with reference to FIG. 1, a general description of the gripping system 1 in the present embodiment will be given. FIG. 1 is a perspective view showing the appearance of the gripping system 1 according to the present embodiment.

[0034] The gripping system 1 is a system that grips and releases an object and distributes the object. Examples of the object include food ingredients such as vegetables. For example, the gripping system 1 grips the food ingredient and releases it into a container 31 such as a container for a whole vegetable or a container for a lunch box, and distributes (arranges) the food ingredient into the container 31. For example, a plurality of gripping systems 1 are arranged, and various food ingredients are sequentially released into the container 31, so that various food ingredients are arranged in the container 31.

[0035] As shown in FIG. 1, the gripping system 1 includes a robot 10, an object storage unit 20, a container supply unit 30, a cover unit 40, and a control device 50. A belt conveyor 2 that automatically transports the container 31 is arranged at a position adjacent to the gripping system 1.

[0036] The robot 10 is an articulated robot such as a horizontal articulated robot or a vertical articulated robot, and grips and releases an object. The robot 10 includes a hand 11 and a robot arm 12. In the present embodiment, the gripping system 1 includes a plurality of robots 10 (specifically, robots 10a and 10b which are two robots 10). The plurality of robots 10 have the same configuration and the same functions, and each of the plurality of robots 10 includes a hand 11 and a robot arm 12.

[0037] The hand 11 is a part that grips and releases an object. The hand 11 is provided with a sensor (not shown) that acquires the amount of the object gripped or released, the reaction force from the contacted object, and the like. The sensor is a weight sensor that measures the weight of the object gripped or released, a force sensor that measures the reaction force from the contacted object (including the sense of force obtained by contacting the surface), and the like. In the present embodiment, the sensor is provided at the connection portion of the hand 11 with the robot arm 12 (connection portion 400 shown in FIG. 2). The data acquired by the sensor is output to the control device 50. A detailed description of the configuration of the hand 11 will be described later.

[0038] The robot arm 12 is a multi-joint arm that moves the hand 11 to a desired position within its range of motion. The robot arm 12 also has an axis at the connection part with the hand 11 that rotates the hand 11 in the twisting direction with respect to the robot arm 12. This allows the orientation of the hand 11 to be changed when the hand 11 grasps or releases an object, and the direction in which the hand 11 opens and closes can be adjusted.

[0039] The object storage unit 20 is a part that stores the objects grasped by the robot 10. The object storage unit 20 is a bat (weight), a tray, or the like. For example, the object storage unit 20 stores a plurality of servings (tens to hundreds of servings, etc.) of food ingredients. The robot 10 grasps the food ingredients from within the object storage unit 20 and releases them into the container 31, thereby portioning (plating) the food ingredients into the container 31.

[0040] The container supply unit 30 supplies the container 31 to the position P where the robot 10 releases the object. The container supply unit 30 stores a plurality of containers 31 inside and supplies the containers 31 to the position P one by one. A weight sensor (not shown) for measuring the weight of the container 31 is arranged at the position P. When an object is placed on the container 31 at the position P, the weight of the object (the increased weight before and after the placement of the object) is measured by the weight sensor. The data measured by the weight sensor is output to the control device 50. When the measurement by the weight sensor is completed, the container 31 with the object placed on it is carried out to the belt conveyor 2 by an extrusion mechanism (not shown) provided in the container supply unit 30.

[0041] The cover unit 40 is a cover that includes a plate-like member surrounding the perimeter and above the area where the robot 10, the object storage unit 20, and the container supply unit 30 are arranged. The plate-like member is formed of a transparent material such as glass or resin, and the operating status of the robot 10 and the like can be visually recognized from the outside of the cover unit 40. An opening / closing door is provided on the side wall of the cover unit 40, and various operations such as replacement of the object storage unit 20, addition of the container 31 to the container supply unit 30, or maintenance of the robot 10 and the like can be performed through the door.

[0042] The control device 50 is a device that controls the operation of the robot 10. The control device 50 controls the operation of at least one of the plurality of robots 10 (at least one of the robot 10a and the robot 10b). In the present embodiment, the control device 50 controls the operations of the plurality of robots 10 (both the robot 10a and the robot 10b). The control device 50 is a computer including a CPU (Central Processing Unit), a ROM (Read Only Memory), a RAM (Random Access Memory), an input unit (such as a keyboard, a touch panel, a mouse, a microphone, etc.), an output unit (such as a liquid crystal display, a speaker, etc.), a communication unit that communicates via a network, and a drive, etc., and executes various processes according to a program. The control device 50 may be realized by a general-purpose computer system such as a personal computer executing a program, or may be realized by a dedicated computer system such as a programmable controller.

[0043] The control device 50 is connected to the robot 10, the container supply unit 30, etc. by wire or wirelessly, and controls the operation of the entire gripping system 1 of the robot 10, the container supply unit 30, etc. For example, the control device 50 controls the operation of the container supply unit 30 supplying the container 31 to the position P, the operation of the robot 10 gripping an object from the object storage unit 20 and releasing it into the container 31, and the operation of the container supply unit 30 carrying out the container 31 to the belt conveyor 2, etc. The control device 50 may be arranged at a location away from the robot 10, etc., or may be arranged in the vicinity of the robot 10, etc., such as being attached to the cover unit 40. The gripping system 1 includes a plurality of sets of configurations in which the robot 10, etc. are housed in the cover unit 40, and the control device 50 may control the operations of the plurality of sets of robots 10, etc. A detailed description of the configuration of the control device 50 will be described later.

[0044] [Description of the hand 11 of the robot 10] Next, the configuration of the hand 11 of the robot 10 in the gripping system 1 of the present embodiment will be described in detail. FIG. 2 is a perspective view showing the configuration of the hand 11 of the robot 10 according to the present embodiment. In FIG. 2, the illustration of the configuration above the upper part of the connection portion 400 of the hand 11 with the robot arm 12 is omitted. FIG. 3 is a perspective view showing the configuration of the gripping member 100 of the hand 11 of the robot 10 according to the present embodiment. FIG. 4 is a front view showing the opening and closing operation of the gripping member 100 of the hand 11 of the robot 10 according to the present embodiment. Specifically, FIG. 4(a) shows a state where the two gripping members 100 are closed, and FIG. 4(b) shows a state where the two gripping members 100 are open. FIG. 5 is a schematic view showing the gripping member 100 of the hand 11 of the robot 10 (robot 10a and robot 10b) according to the present embodiment and the object housing portion 20.

[0045] In the following description and drawings, the direction in which the hand 11 (two gripping members 100) of the robot 10 faces forward is defined as the X-axis direction, the direction in which the two gripping members 100 open and close is defined as the Y-axis direction, and the vertical direction is defined as the Z-axis direction. These X-axis direction, Y-axis direction, and Z-axis direction are directions that intersect (orthogonal in the present embodiment) with each other. As described above, the hand 11 (two gripping members 100) is configured to be rotatable about an axis parallel to the Z-axis. However, when the hand 11 rotates, the X-axis and Y-axis will also rotate accordingly. Also, in the following description, the X-axis plus direction indicates the arrow direction of the X-axis, and the X-axis minus direction indicates the direction opposite to the X-axis plus direction. When simply referring to the X-axis direction, it indicates the two-way or one-way direction of the X-axis plus direction and the X-axis minus direction. The same applies to the Y-axis direction and the Z-axis direction. Expressions indicating relative directions or postures such as parallel and orthogonal include cases where they are not strictly in that direction or posture. For example, two directions being parallel means not only that the two directions are completely parallel, but also that they are substantially parallel, that is, including a difference of about several percent.

[0046] As shown in FIG. 2, in addition to the above-described connection portion 400, the hand 11 of the robot 10 includes two (a pair of) gripping members 100, two (a pair of) moving portions 200, and a guide portion 300.

[0047] The two gripping members 100 are members for gripping an object. Specifically, the two gripping members 100 grip and release the object. That is, the two gripping members 100 grip and release a part of the object accommodated in the object accommodating portion 20. In the present embodiment, the gripping member 100 is a member made of metal, but may be a member other than metal such as a resin member. As shown in FIG. 3, each of the two gripping members 100 has a plate-like portion 110 for gripping an object, a pair of side plate portions 120 disposed on both sides of the plate-like portion 110 and facing each other, and a top plate portion 130 disposed above the plate-like portion 110. Hereinafter, the gripping member 100 located in the minus Y-axis direction among the two gripping members 100 is also referred to as a gripping member 101, and the gripping member 100 located in the plus Y-axis direction is also referred to as a gripping member 102. That is, as shown in FIG. 3, the gripping member 101 has a plate-like portion 111, a pair of side plate portions 121, and a top plate portion 131. The gripping member 102 has a plate-like portion 112, a pair of side plate portions 122, and a top plate portion 132. The gripping member 101 and the gripping member 102 have a configuration that is symmetric with respect to the XZ plane.

[0048] The plate-like portions 111 and 112 are main body portions of the gripping members 101 and 102. When the gripping members 101 and 102 grip an object, they are disposed on both sides in the Y-axis direction of the object and sandwich the object in the Y-axis direction to grip the object. The plate-like portion 111 is a flat plate-like and rectangular portion that is inclined in the minus Y-axis direction from the XZ plane as it goes in the plus Z-axis direction. The plate-like portion 112 is a flat plate-like and rectangular portion that is inclined in the plus Y-axis direction from the XZ plane as it goes in the plus Z-axis direction. That is, the plate-like portions 111 and 112 are inclined so as to be separated from each other (the interval widens) as they go in the plus Z-axis direction. Note that as long as the object can be gripped by the plate-like portions 111 and 112, one or both of the plate-like portions 111 and 112 may not be inclined and may be a plate-like portion (vertical plate) parallel to the XZ plane.

[0049] The pair of side plate portions 121 are flat plate-like and reverse triangular portions parallel to the YZ plane that protrude in the plus Y-axis direction from both ends of the plate-like portion 111 in the X-axis direction. When the gripping members 101 and 102 grip an object, the pair of side plate portions 121 are arranged on both sides of the object in the X-axis direction and sandwich the object in the X-axis direction. The pair of side plate portions 122 are flat plate-like and reverse triangular portions parallel to the YZ plane that protrude in the minus Y-axis direction from both ends of the plate-like portion 112 in the X-axis direction. When the gripping members 101 and 102 grip an object, the pair of side plate portions 122 are arranged on both sides of the object in the X-axis direction and sandwich the object in the X-axis direction.

[0050] The top plate portion 131 is a flat plate-like and rectangular portion parallel to the XY plane that protrudes in the plus Y-axis direction from the plus Z-axis direction end of the plate-like portion 111. The top plate portion 132 is a flat plate-like and rectangular portion parallel to the XY plane that protrudes in the minus Y-axis direction from the plus Z-axis direction end of the plate-like portion 112. The top plate portions 131 and 132 are arranged in the plus Z-axis direction of the object when the gripping members 101 and 102 grip the object.

[0051] The two moving portions 200 are portions configured to be movable (slidable) in the Y-axis direction with respect to the guide portion 300. The two moving portions 200 are connected to the plus Z-axis direction ends of the two gripping members 100 and move (slide) the two gripping members 100 in the Y-axis direction. Hereinafter, among the two moving portions 200, the moving portion 200 located in the minus Y-axis direction is also referred to as the moving portion 201, and the moving portion 200 located in the plus Y-axis direction is also referred to as the moving portion 202. The moving portion 201 is connected to the plus Z-axis direction end of the gripping member 101 and moves (slides) the gripping member 101 in the Y-axis direction. The moving portion 202 is connected to the plus Z-axis direction end of the gripping member 102 and moves (slides) the gripping member 102 in the Y-axis direction.

[0052] As shown in FIG. 4, the moving parts 201 and 202 move away from each other or approach each other in the Y-axis direction, thereby increasing or decreasing the distance between the gripping members 101 and 102 to open or close the gripping members 101 and 102. In the present embodiment, the moving parts 201 and 202 are configured to be able to move stepwise with respect to the guide part 300, and the distance between the gripping members 101 and 102 can be adjusted stepwise. Only one of the moving parts 201 and 202, instead of both, may be configured to be movable with respect to the guide part 300.

[0053] The guide part 300 is a guide that guides the two moving parts 200 to be movable (slidable) in the Y-axis direction. In the present embodiment, the guide part 300 has a linear rail extending in the Y-axis direction, and the two moving parts 200 move (slide) in the Y-axis direction along this rail.

[0054] As shown in FIG. 4(a), in the state where the gripping member 101 and the gripping member 102 are completely closed, the minus Z-axis direction end of the plate-like part 111 and the minus Z-axis direction end of the plate-like part 112 are in contact, and the side plate part 121 and the side plate part 122 are in contact. Thereby, the gripping members 101 and 102 have an inverted isosceles triangle container shape when viewed from the X-axis direction. In the present embodiment, slight gaps are formed at both ends in the Z-axis direction of the side plate part 121 and the side plate part 122, but these gaps may not be formed. The gripping members 101 and 102 may be opened and closed by the moving parts 201 and 202 rotating around an axis parallel to the X-axis. However, when the moving parts 201 and 202 move in the Y-axis direction, the gripping members 101 and 102 can grip more objects at a deep position in the object accommodating part 20.

[0055] As described above, the gripping system 1 includes two robots 10a and 10b that have the same configuration and the same functions. For this reason, as shown in FIG. 5, the robot 10a has two gripping members 100a (101a and 102a) as two gripping members 100 (101 and 102). The robot 10b has two gripping members 100b (101b and 102b) as two gripping members 100 (101 and 102). The two gripping members 100a (101a and 102a) grip the object T1 accommodated in the region R1 among the objects T accommodated in the region R in the object accommodation unit 20. The two gripping members 100b (101b and 102b) grip the object T2 accommodated in the region R2 among the objects T accommodated in the region R in the object accommodation unit 20. Also, hereinafter, the distance between the two gripping members 100 (101 and 102) is also referred to as the distance L. The distance between the two gripping members 100a (101a and 102a) is also referred to as the distance La, and the distance between the two gripping members 100b (101b and 102b) is also referred to as the distance Lb.

[0056] [Explanation of the Functional Configuration of the Control Device 50] Next, the functional configuration of the control device 50 will be described in detail below. FIG. 6 is a block diagram showing the functional configuration of the control device 50 according to the present embodiment.

[0057] As shown in FIG. 6, the control device 50 includes a first control unit 51, a second control unit 52, and a storage unit 54. The first control unit 51 is a processing unit that controls a plurality of robots 10 and causes the two gripping members 100 included in the robot 10 to grip and release the object T. The second control unit 52 is a processing unit that controls various devices other than the robot 10 in the gripping system 1. The storage unit 54 is a memory that stores data and the like for performing various controls in the gripping system 1. Hereinafter, each of these processing units will be described in detail.

[0058] The first control unit 51 causes each of the plurality of robots 10 to grip a part of the object T, and causes the first robot that has gripped the first object, among the plurality of robots 10, whose weight value has first fallen within a predetermined range, to release the first object. Specifically, the first control unit 51 causes each of the plurality of robots 10 to grip a part of the object T in the object storage unit 20, and causes the first robot that has gripped the first object, among the plurality of robots 10, whose weight value has first fallen within a predetermined range, to release the first object into the container 31. Further, the first control unit 51 causes a second robot different from the first robot among the plurality of robots 10 to release the gripped second object and grip a part of the object T again. Specifically, the first control unit 51 causes the second robot to release the gripped second object into the object storage unit 20 and grip a part of the object T in the object storage unit 20 again. The second object is the same type of object (such as food ingredients) as the first object.

[0059] Further, when the first control unit 51 determines that the weight value of the first object grasped and released by the first robot is smaller than the first predetermined value although it is within the predetermined range, the first control unit 51 causes any one of the plurality of robots 10 to grasp a part of the object T. Then, the first control unit 51 causes the third robot that has grasped the third object whose weight value has become the difference between the weight value of the first object and the first predetermined value among the plurality of robots 10 to release the third object. Specifically, the first control unit 51 causes the third robot to release the third object into the container 31 from which the first robot has released the first object. Alternatively, when the first control unit 51 determines that the weight value of the first object grasped and released by the first robot is larger than the second predetermined value although it is within the predetermined range, the first control unit 51 causes any one of the plurality of robots 10 to grasp a part of the first object. Then, the first control unit 51 causes the fourth robot that has grasped the fourth object whose weight value has become the difference between the weight value of the first object and the second predetermined value among the plurality of robots 10 to release the fourth object at a position different from the first object. Specifically, the first control unit 51 causes the fourth robot that has grasped the fourth object from within the container 31 from which the first robot has released the first object to release the fourth object at a position different from the container 31. Note that since the fourth object is a part of the first object, it is an object (such as food ingredients) of the same type as the first object.

[0060] Further, the first control unit 51 causes one of the plurality of robots 10 to grasp the object T located in the first region and causes the other robots 10 to grasp the object T located in the second region. Then, the first control unit 51 detects the amount of the object T remaining in the first region and the second region, and causes one of the robots 10 to grasp the object T located in the second region or the object T located at the boundary between the first region and the second region under predetermined conditions.

[0061] Also, when the first control unit 51 causes the robot 10 to grip and then release a part of the object T, it performs the following processing. The first control unit 51 changes the distance L between the two gripping members 100 of the robot 10. Specifically, the first control unit 51 changes the distance L between the two gripping members 100 of the robot 10 to a third distance different from the first distance during the opening operation and the second distance during the closing operation when the two gripping members 100 grip or release the object T. The first distance is the maximum distance (maximum opening width) between the two gripping members 100 during the opening operation when the two gripping members 100 grip or release the object T. The second distance is the minimum distance (minimum opening width (closing width)) between the two gripping members 100 during the closing operation when the two gripping members 100 grip the object T. That is, the third distance is a width (distance) different from the maximum and minimum opening widths during the gripping and releasing operations of the two gripping members 100. The third distance is not a fixed value and is appropriately changed according to the situation. Here, the gripping system 1 includes two robots 10, namely robot 10a and robot 10b. Therefore, the first control unit 51 performs the above operation (the operation of changing the distance between the two gripping members 100 to a width (distance) different from the maximum and minimum opening widths during the gripping and releasing operations) on at least one of the robot 10a and the robot 10b. In the present embodiment, the first control unit 51 performs the above operation on both the robot 10a and the robot 10b.

[0062] Further, the first control unit 51 determines the depth at which the two gripping members 100 are inserted into the object T according to the distance between the two gripping members 100. Here, the "distance between the two gripping members 100" refers to the maximum distance (maximum opening width) between the two gripping members 100 during the opening operation when the two gripping members 100 grip the object T. That is, the first control unit 51 determines the depth at which the two gripping members 100 are inserted into the object T according to the maximum opening width during the gripping operation of the two gripping members 100. Also, the "depth of insertion into the object T" refers to the depth of penetration into the object T, the depth of insertion (penetration distance) from the surface of the object T, or the depth after contacting the object T, etc. The first control unit 51 may determine the depth after both of the two gripping members 100 contact the object T, but in this embodiment, it is determined to be the depth after at least one of the gripping members 100 contacts the object T. The first control unit 51 performs the above determination (determines the depth at which the two gripping members 100 are inserted into the object T according to the distance between the two gripping members 100) for at least one of the robot 10a and the robot 10b. In this embodiment, the first control unit 51 performs the above determination for both the robot 10a and the robot 10b.

[0063] The second control unit 52 controls devices not controlled by the first control unit 51 in the gripping system 1. That is, the first control unit 51 controls the operation of the robot 10, and the second control unit 52 controls devices other than the robot 10 such as the container supply unit 30. Specifically, the second control unit 52 controls the operation of the container supply unit 30 supplying the container 31 to the position P, and the operation of the container supply unit 30 carrying out the container 31 from the position P to the belt conveyor 2, etc.

[0064] The storage unit 54 is composed of a hard disk or a DRAM (Dynamic Random Access Memory), etc., and is a memory that stores data, etc. for controlling various operations in the gripping system 1. Specifically, the storage unit 54 stores control data 54a including data, etc. for the control device 50 to control the operation of the robot 10 (robot 10a and robot 10b).

[0065] [Explanation of the Processing Flow of the Control Device 50] Next, the control processing performed by the control device 50 will be described. In particular, the processing in which the first control unit 51 of the control device 50 controls the operations of a plurality of robots 10 (robot 10a and robot 10b) will be described in detail. FIG. 7 is a flowchart showing the processing in which the control device 50 according to the present embodiment controls the operation of the robot 10.

[0066] As shown in FIG. 7, first, the first control unit 51 of the control device 50 causes each of the plurality of robots 10 to grip a part of the object T (step S11). That is, the first control unit 51 causes each of the two gripping members 100 of each of the plurality of robots 10 to grip a part of the object T in the object storage unit 20. For example, the first control unit 51 causes the two gripping members 100a of the robot 10a to grip the object T1 located in the region R1 in the object storage unit 20, and causes the two gripping members 100b of the robot 10b to grip the object T2 located in the region R2 in the object storage unit 20. At this time, the first control unit 51 changes the distance between the two gripping members 100 to a distance different from the distance during a normal gripping operation, or determines the depth at which the two gripping members 100 are inserted into the object T according to the distance between the two gripping members 100. A detailed description of the processing in step S11 will be described later.

[0067] Next, until the control is terminated (the work by the plurality of robots 10 is terminated), the first control unit 51 repeatedly performs the following processing (steps S13 to S17) (loop 1: steps S12 to S18).

[0068] First, the first control unit 51 determines the first robot that has grasped the first object whose weight value has first fallen within a predetermined range among the plurality of robots 10 (step S13). For example, the value of the predetermined range is pre-written in the control data 54a, and the first control unit 51 reads and acquires the predetermined range from the control data 54a. Further, the first control unit 51 measures and acquires the weight value of the object T grasped by the robot 10 by means of a weight sensor or the like provided on the hand 11. Thereby, the first control unit 51 compares the weight value of the object T grasped by each robot 10 with the predetermined range, and determines the robot 10 that has grasped the object T whose weight value has first fallen within the predetermined range as the first robot. The first control unit 51 writes the weight value of the object T grasped by each robot 10 and which robot 10 has been determined as the first robot into the control data 54a of the storage unit 54 and stores it in the storage unit 54.

[0069] For example, it is assumed that the robot 10a has grasped the object T1 whose weight value has fallen within the predetermined range earlier than the robot 10b. In this case, the first control unit 51 determines the robot 10a as the first robot and determines the object T1 grasped by the robot 10a as the first object. When a plurality of robots 10 grasp the object T having a weight value within the predetermined range at the same timing, the first control unit 51 determines the robot 10 that has grasped the object T having a weight value closest to the median value of the predetermined range as the first robot. When none of the robots 10 can grasp the object T having a weight value within the predetermined range, the first control unit 51 causes each robot 10 to grasp the object T again. Since the process by which the first control unit 51 causes the robot 10 to grasp the object T again is the same as the process performed in step S17 described later, a detailed description thereof is omitted.

[0070] Next, the first control unit 51 causes the first robot to release the first object (step S14). Specifically, the first control unit 51 causes the first object to be released into the container 31 by the two gripping members 100 of the first robot. For example, the first control unit 51 reads and acquires from the control data 54a in the storage unit 54 which robot 10 has been determined as the first robot, and causes the first robot to release the first object. Details of the processing in step S14 will be described later.

[0071] Next, the first control unit 51 adjusts the weight of the first object that the first robot has gripped and released (step S15). Specifically, the first control unit 51 adjusts the weight of the first object so that the weight value of the first object falls within a range that is further within the above-mentioned predetermined range and is greater than or equal to a first predetermined value and less than or equal to a second predetermined value. For this reason, when the weight value of the first object is smaller than the first predetermined value or larger than the second predetermined value, the first control unit 51 increases or decreases the amount of the first object by any of the plurality of robots 10. The first predetermined value and the second predetermined value are weight values within the above-mentioned predetermined range, and are, for example, pre-written in the control data 54a of the storage unit 54, and the first control unit 51 reads and acquires these values from the control data 54a. Details of the processing in step S15 will be described later.

[0072] Next, the first control unit 51 determines the area where the robot 10 grips the object T (step S16). Specifically, the first control unit 51 determines the area where the robot 10 grips the object T according to the amount of the object T remaining in the object storage unit 20. Details of the processing in step S16 will be described later.

[0073] Next, the first control unit 51 causes each of the plurality of robots 10 to grip a part of the object T again (step S17). Specifically, after the first robot releases the first object, the first control unit 51 causes the first robot to grip a part of the object T again. For robots 10 other than the first robot, if the gripped object has been released, the first control unit 51 causes them to grip a part of the object T again. That is, the first control unit 51 causes a second robot different from the first robot among the plurality of robots 10 to release the gripped second object and grip a part of the object T again. In the present embodiment, the first control unit 51 has decided not to cause a second robot different from the first robot to release the gripped second object until the first robot releases the first object. However, even before the first robot releases the first object, the second robot may be caused to release the second object and grip a part of the object T again. A detailed description of the processing in step S17 will be given later.

[0074] As described above, the first control unit 51 repeatedly executes the processing of steps S13 to S17 in loop 1 (steps S12 to S18). When loop 1 ends, the processing in which the first control unit 51 controls the operations of the plurality of robots 10 ends.

[0075] [4.1 Explanation of Step S11] Next, the processing (step S11 in FIG. 7) in which the first control unit 51 causes each of the plurality of robots 10 to grip a part of the object T will be described in detail. Since each robot 10 performs the same gripping operation, hereinafter, the processing in which the first control unit 51 causes one robot 10 to grip a part of the object T will be described. Also, unless otherwise specified, the gripping operations in other steps are the same as this step.

[0076] FIG. 8 is a flowchart showing the processing (step S11 in FIG. 7) in which the first control unit 51 according to the present embodiment causes the robot 10 to grip a part of the object T.

[0077] As shown in FIG. 8, first, the first control unit 51 changes the distance L between the two gripping members 100 of the robot 10 to a third distance different from the first distance during the opening operation and the second distance during the closing operation when the two gripping members 100 grip or release the object T (step S110). For example, the first control unit 51 changes the distance L between the two gripping members 100 to a third distance according to the object T gripped by the two gripping members 100. That is, when the first control unit 51 determines that it is difficult to grip the object T at the preset distance L because the size of the object T to be gripped is large or small, the object T has a distorted shape, or the object T is likely to collapse, the first control unit 51 changes the distance L to the third distance. Alternatively, when the first control unit 51 determines that the depth of the object T is equal to or less than a predetermined value (first depth), the first control unit 51 widens the distance L between the two gripping members 100. In this way, the first control unit 51 determines the distance L between the two gripping members 100 according to the object T. In the subsequent processing, when the first control unit 51 changes the distance L between the two gripping members 100, the first control unit 51 may appropriately determine the distance L according to the object T.

[0078] For example, information on the object T is written in the control data 54a, and the first control unit 51 can determine what value to change the distance L to by reading and acquiring the information on the object T from the control data 54a. The first control unit 51 can also acquire the depth of the object T in the process of detecting the shape of the object T in step S152 described later. The above-mentioned first distance, second distance, third distance, and first depth are respectively preset or determined by the first control unit 51 and written in the control data 54a of the storage unit 54 to be stored in the storage unit 54. When any of the first distance, second distance, third distance, and first depth is changed, the data written in the control data 54a is rewritten.

[0079] Next, the first control unit 51 determines the depth at which the two gripping members 100 are inserted into the object T according to the distance L between the two gripping members 100 (step S120). In the present embodiment, since the first control unit 51 changes the distance L between the two gripping members 100 to a third distance, the first control unit 51 determines the insertion depth corresponding to the case where the distance L is the third distance. For example, when the first control unit 51 widens the distance L between the two gripping members 100, in order to grip an object T of relatively fixed quantity, etc., the first control unit 51 shallows the depth at which the two gripping members 100 are inserted into the object T. To shallows the depth means to make it shallower than the depth (a preset value, an initial value, or, if the depth has been changed thereafter, the value after the change) immediately before the shallowing operation (immediately before the process, immediately before the judgment). The same applies to the case of deepening the depth.

[0080] In addition, when the first control unit 51 widens the distance L between the two gripping members 100 and determines that the object T is large and the object T cannot be gripped unless the insertion depth is deepened, the first control unit 51 may deepen the depth at which the two gripping members 100 are inserted into the object T. Thus, the first control unit 51 determines the depth at which the two gripping members 100 are inserted into the object T according to the situation of the object T, etc. In the subsequent processing, even when the first control unit 51 changes the depth at which the two gripping members 100 are inserted into the object T, the first control unit 51 may appropriately determine the insertion depth according to the situation of the object T, etc.

[0081] For example, the first control unit 51 can determine what value to set for the insertion depth by reading and obtaining the information of the object T from the control data 54a. The insertion depth and the relationship (relationship formula, etc.) between the distance between the two gripping members 100 and the insertion depth are preset or determined by the first control unit 51 and written into the control data 54a of the storage unit 54 for storage in the storage unit 54. When the insertion depth or the relationship (relationship formula, etc.) between the distance between the two gripping members 100 and the insertion depth is changed, the data written in the control data 54a is rewritten.

[0082] Next, the first control unit 51 moves the two gripping members 100 toward the object T (step S130). That is, the first control unit 51 changes the distance L between the two gripping members 100 to a third distance, and after determining the depth at which the two gripping members 100 are inserted into the object T, moves the two gripping members 100 toward the object T. Note that the first control unit 51 may change the distance L to the third distance or determine the insertion depth while moving the two gripping members 100 toward the object T.

[0083] Next, the first control unit 51 determines whether a force in a direction away from the object T is applied to at least one of the two gripping members 100 (step S140). Specifically, the first control unit 51 determines whether a force equal to or greater than a first stress (a value close to 0) in a direction away from the object T is applied to at least one of the gripping members 100. For example, the value of the first stress is pre-written in the control data 54a, and the first control unit 51 reads and acquires the first stress from the control data 54a, and acquires the force applied to the gripping member 100 by a weight sensor, a force sensor, or the like provided on the hand 11. Then, when the force applied to the gripping member 100 becomes equal to or greater than the first stress, the first control unit 51 determines that a force in a direction away from the object T is applied to the gripping member 100. The first control unit 51 moves the two gripping members 100 toward the object T until it determines that a force in a direction away from the object T is applied to at least one of the gripping members 100 (when NO in step S140, step S130 is repeated). When the first control unit 51 determines that a force in a direction away from the object T is applied to at least one of the two gripping members 100 (YES in step S140), it proceeds to the next step S150.

[0084] Then, the first control unit 51 changes the distance L between the two gripping members 100 and changes the depth at which the gripping members 100 are inserted into the object T (step S150). Hereinafter, this step S150 will be described in detail.

[0085] [4.1.1 Explanation of Step S150] FIG. 9 is a flowchart showing a process (step S150 in FIG. 8) in which the first control unit 51 according to the present embodiment changes the distance L between the two gripping members 100 and the depth at which the gripping member 100 is inserted into the object T. FIG. 10 is a schematic diagram for explaining a process (step S150 in FIG. 8) in which the first control unit 51 according to the present embodiment changes the distance L between the two gripping members 100 and the depth at which the gripping member 100 is inserted into the object T.

[0086] As shown in FIG. 9, when the first control unit 51 determines that a force in a direction away from the object T is applied to at least one of the two gripping members 100 (YES in step S140), the first control unit 51 determines that the gripping member 100 has come into contact with the object T (step S151). That is, as shown in FIG. 10(a), when the two gripping members 100 move in the negative Z-axis direction toward the object T and at least one of the gripping members 100 comes into contact with the object T, a force in the positive Z-axis direction is applied to the gripping member 100. Therefore, when the first control unit 51 determines that a force in the positive Z-axis direction is applied to at least one of the gripping members 100, the first control unit 51 determines that the gripping member 100 has come into contact with the object T.

[0087] Then, the first control unit 51 detects the shape of the object T (step S152). That is, the first control unit 51 detects the shape of the object T by determining that at least one of the two gripping members 100 has come into contact with the object T. When the gripping member 100 comes into contact with the object T, the first control unit 51 writes data such as which gripping member 100 has come into contact with the object T, and the position and height at which the gripping member 100 has come into contact with the object T into the control data 54a and stores it in the storage unit 54. Thereby, the first control unit 51 estimates the shape of the surface of the object T by accumulating the data in the control data 54a.

[0088] Next, the first control unit 51 determines whether or not a force equal to or greater than a predetermined value in a direction away from the object T is applied to at least one of the two gripping members 100 (step S153). Specifically, the first control unit 51 determines whether or not a force equal to or greater than a second stress (a value greater than the first stress) in a direction away from the object T is applied to at least one of the gripping members 100. For example, the value of the second stress is written in advance in the control data 54a, and the first control unit 51 reads and acquires the second stress from the control data 54a, and acquires the force applied to the gripping member 100 by a weight sensor, a force sensor, or the like provided in the hand 11. Then, when the force applied to the gripping member 100 becomes equal to or greater than the second stress, the first control unit 51 determines that a force equal to or greater than a predetermined value in a direction away from the object T is applied to the gripping member 100.

[0089] When the first control unit 51 determines that a force equal to or greater than a predetermined value in a direction away from the object T is applied to at least one of the two gripping members 100 (YES in step S153), the first control unit 51 changes the distance L between the two gripping members 100 and the depth at which the gripping member 100 is inserted into the object T (step S154).

[0090] For example, when the first control unit 51 determines that a force equal to or greater than a predetermined value is applied to at least one of the gripping members 100, since there is a possibility that the gripping member 100 is in contact with the object T at an inappropriate position, the first control unit 51 changes the distance L between the two gripping members 100 to a distance greater than a third distance. Specifically, as shown in FIGS. 10(a) and 10(b), the first control unit 51 changes the distance L between the two gripping members 100 to a distance L2 greater than the third distance L1.

[0091] Further, in the present embodiment, as shown in FIG. 10(a), the surface of the object T is uneven, and only one of the two gripping members 100, i.e., the gripping member 101, is in contact with the object T. In this case, if the object T is gripped with the value of the distance L between the two preset gripping members 100, the amount of the object T to be gripped may be reduced. Therefore, as shown in FIG. 10(b), the first control unit 51 increases the distance L between the two gripping members 100. That is, when the first control unit 51 determines that only one of the two gripping members 100, i.e., one gripping member 100, is in contact with the object T (a force equal to or greater than a predetermined value is applied), the first control unit 51 increases the distance L between the two gripping members 100.

[0092] Alternatively, as shown in FIG. 10(a), when only one gripping member 101 is in contact with the object T, if the object T is gripped with the preset value of the depth at which the gripping member 100 is inserted into the object T, the amount of the object T to be gripped may be reduced. Therefore, as shown in FIG. 10(c), the first control unit 51 increases the depth at which the gripping member 100 is inserted into the object T. That is, when the first control unit 51 determines that only one of the two gripping members 100, i.e., one gripping member 100, is in contact with the object T (a force equal to or greater than a predetermined value is applied), the first control unit 51 increases the depth at which the gripping member 100 is inserted into the object T.

[0093] In this way, the first control unit 51 changes the distance L between the two gripping members 100 or changes the depth at which the gripping member 100 is inserted into the object T. Note that the first control unit 51 may change both the distance L between the two gripping members 100 and the depth at which the gripping member 100 is inserted into the object T.

[0094] Further, when the first control unit 51 determines that a force equal to or greater than a predetermined value in the direction away from the object T is not applied to both of the two gripping members 100 (NO in step S153), the process ends. As described above, the process (step S150 in FIG. 8) in which the first control unit 51 changes the distance L between the two gripping members 100 and the depth at which the gripping member 100 is inserted into the object T ends.

[0095] Returning to FIG. 8, next, the first control unit 51 causes the two gripping members 100 to grip the object T (step S160). Hereinafter, this step S160 will be described in detail.

[0096] [4.1.2 Explanation of Step S160] FIG. 11 is a flowchart showing the process in which the first control unit 51 according to the present embodiment causes the two gripping members 100 to grip the object T (step S160 in FIG. 8). FIGS. 12 to 14 are schematic diagrams for explaining the process in which the first control unit 51 according to the present embodiment causes the two gripping members 100 to grip the object T (step S160 in FIG. 8).

[0097] As shown in FIG. 11, first, when the two gripping members 100 perform a closing operation to grip the object T, the first control unit 51 determines whether the two gripping members 100 grip the object T while the distance L between the two gripping members 100 remains the second distance (step S161).

[0098] When the first control unit 51 determines that the two gripping members 100 grip the object T while the distance L during the closing operation remains the second distance (YES in step S161), the first control unit 51 causes the two gripping members 100 to grip the object T and determines whether to change the distance L from the second distance (step S162). When the first control unit 51 determines not to change the distance L from the second distance (NO in step S162), the process ends. Specifically, as shown in FIGS. 12(a) to 12(c), when the two gripping members 100 perform a closing operation, the first control unit 51 closes the distance L from, for example, the distance L2 to the second distance L3 and causes the two gripping members 100 to grip the object T.

[0099] Here, in the state of (c) in FIG. 12, when the amount of the object T gripped by the two gripping members 100 is too large or in other cases where it is desired to reduce the amount of the object T gripped by the two gripping members 100, the first control unit 51 determines to change the distance L from the second distance (YES in step S162), and changes the distance L between the two gripping members 100 from the second distance to a third distance greater than the second distance (step S163). Then, the first control unit 51 returns the distance L between the two gripping members 100 to the second distance (step S164).

[0100] Specifically, as shown in (a) of FIG. 13, the first control unit 51 changes the distance L between the two gripping members 100 from the second distance L3 shown in (c) of FIG. 12 to a third distance L4 greater than the second distance L3. Thereby, the object T falls from between the two gripping members 100, and the amount of the object T gripped by the two gripping members 100 is reduced. Then, as shown in (b) of FIG. 13, the first control unit 51 returns the distance L between the two gripping members 100 to the second distance L3 and grips the object T. Thereby, the amount of the object T gripped by the two gripping members 100 is adjusted. Note that, from the state of (b) in FIG. 12, without lifting the two gripping members 100, by changing the distance L between the two gripping members 100 to the third distance L4, the object T may be dropped from between the two gripping members 100. As described above, the first control unit 51 changes the distance L between the two gripping members 100 during the closing operation to a third distance L4 greater than the second distance L3 after setting the distance L to the second distance L3, and then returns it to the second distance L3.

[0101] When the first control unit 51 determines that the two gripping members 100 will not grip the object T if the distance L during the closing operation remains the second distance (NO in step S161), the first control unit 51 changes the distance L between the two gripping members 100 during the closing operation from the second distance to a third distance greater than the second distance (step S165). That is, when the distance L during the closing operation makes it difficult for the two gripping members 100 to grip the object T if it remains the second distance, the first control unit 51 widens the distance L during the closing operation to make it easier for the two gripping members 100 to grip the object T. Then, the first control unit 51 causes the two gripping members 100 to grip the object T at the third distance (step S166). Specifically, as shown in FIG. 14, the first control unit 51 changes the distance L between the two gripping members 100 during the closing operation not to the second distance L3 but to a third distance L4 greater than the second distance L3, and causes the two gripping members 100 to grip the object T at the third distance L4.

[0102] In FIGS. 12 to 14, the second distance, which is the distance between the two gripping members 100 during the closing operation of the two gripping members 100, is set to L3 (a positive value) instead of 0, but the second distance may be 0 (the two gripping members 100 may be completely closed). Alternatively, the first control unit 51 may change the distance L between the two gripping members 100 during the closing operation of the two gripping members 100 from the second distance L3 to a third distance (such as 0) smaller than the second distance L3. Thus, the first control unit 51 may appropriately change the distance L between the two gripping members 100 during the closing operation according to the situation of the object T and the like.

[0103] Further, the first control unit 51 may lock the distance L between the two gripping members 100 at the second distance or the third distance during the closing operation so that the distance L does not become smaller (so that the closing width of the two gripping members 100 does not further shrink). That is, when the first control unit 51 determines the closing width of the two gripping members 100, it may prohibit further shrinkage from that width. Thereby, the closing operation of the two gripping members 100 can be appropriately performed.

[0104] In the manner described above, the process in which the first control unit 51 causes the two gripping members 100 to grip the object T (step S160 in FIG. 8) ends. In this way, the first control unit 51 causes a part of the object T to be gripped by the plurality of robots 10 (step S11 in FIG. 7).

[0105] [4.2 Explanation of Step S14] Next, the process in which the first control unit 51 causes the first robot to release the first object (step S14 in FIG. 7) will be described in detail. FIG. 15 is a flowchart showing the process in which the first control unit 51 according to the present embodiment causes the first robot to release the first object (step S14 in FIG. 7). Note that, unless otherwise specified, the same release operation as this step is performed for the release operations in other steps.

[0106] As shown in FIG. 15, first, when the two gripping members 100 of the first robot release the first object during the opening operation, the first control unit 51 determines whether to release the first object while the distance L between the two gripping members 100 remains the first distance (step S171).

[0107] When the first control unit 51 determines that the two gripping members 100 release the first object while the distance L during the opening operation remains the first distance (YES in step S171), the first control unit 51 sets the distance L between the two gripping members 100 to the first distance and causes the two gripping members 100 to release the first object.

[0108] When the first control unit 51 determines that the two gripping members 100 do not release the first object while the distance L during the opening operation remains the first distance (NO in step S171), the first control unit 51 changes the distance L between the two gripping members 100 during the opening operation from the first distance to a third distance smaller than the first distance (step S172). Then, the first control unit 51 causes the two gripping members 100 to release the first object at the third distance (step S173).

[0109] That is, when the first control unit 51 determines that it is better to reduce the distance L during the opening operation because the size of the container 31 is small and there is a risk that the first object may protrude from the container 31, etc., the first control unit 51 changes the distance L to a third distance smaller than the first distance. For example, information on the container 31 is written in the control data 54a of the storage unit 54, and the first control unit 51 can determine what value to change the distance L to by reading and acquiring the information on the container 31 from the control data 54a. In this way, the first control unit 51 changes the distance L between the two gripping members 100 to a third distance according to the size of the container 31 from which the first object gripped by the two gripping members 100 is released.

[0110] In addition, the first control unit 51 may change the distance L between the two gripping members 100 during the opening operation to a third distance smaller than the first distance after setting the distance L to the first distance. Thereby, the first object can be more liberally released at the central part of the container 31. In particular, by raising the gripping member 100 while gradually narrowing the distance L until it reaches the third distance, the first object can be released in a mountain shape into the container 31 (the food ingredients can be arranged in a mountain shape), improving the appearance.

[0111] Further, the first control unit 51 may change the distance L between the two gripping members 100 from the first distance to a third distance larger than the first distance during the opening operation of the two gripping members 100. In this way, the first control unit 51 may appropriately change the distance L between the two gripping members 100 during the opening operation according to the situation of the first object or the container 31, etc.

[0112] In addition, during the opening operation, the first control unit 51 may lock the distance L between the two gripping members 100 so that the distance L does not increase (so that the opening width of the two gripping members 100 does not further widen) after setting the distance L to the first distance or the third distance. That is, when the first control unit 51 determines the opening width of the two gripping members 100, it may prohibit further widening from that width. Thereby, the opening operation of the two gripping members 100 can be appropriately performed.

[0113] As described above, the process in which the first control unit 51 causes the first robot to release the first object (step S14 in FIG. 7) ends.

[0114] [4.3 Explanation of Step S15] Next, the process in which the first control unit 51 adjusts the weight of the first object that the first robot has grasped and released (step S15 in FIG. 7) will be described in detail. FIG. 16 is a flowchart showing the process in which the first control unit 51 according to the present embodiment adjusts the weight of the first object that the first robot has grasped and released (step S15 in FIG. 7).

[0115] As shown in FIG. 16, first, the first control unit 51 determines whether the weight value of the first object that the first robot has grasped and released is less than a first predetermined value (step S201). The first control unit 51 reads and acquires the weight value of the first object and the first predetermined value from the control data 54a in the storage unit 54, and determines whether the weight value of the first object is less than the first predetermined value. When the first control unit 51 determines that the weight value of the first object is less than the first predetermined value (YES in step S201), it causes any one of the plurality of robots 10 to grasp a part of the object T (step S202). At this time, the first control unit 51 does not need to cause all the robots 10 to grasp a part of the object T, and it is sufficient to cause at least one robot 10 to grasp a part of the object T. Further, it is preferable that the first control unit 51 causes a robot other than the first robot to grasp a part of the object T.

[0116] Then, the first control unit 51 determines the third robot that has gripped the third object among the plurality of robots 10, the weight value of which has become the difference between the weight value of the first object and the first predetermined value earliest (step S203). The process by which the first control unit 51 determines the third robot is the same as the case where the "predetermined range" in the process by which the first control unit 51 determines the first robot is rephrased as the "difference between the weight value of the first object and the first predetermined value", and thus detailed description is omitted. Note that the first predetermined value may be a value within a certain range with a certain width. That is, the weight value of the third object only needs to fall within a certain range with a certain width. Also, in the present embodiment, since the gripping system 1 includes only two robots 10, either the robot 10a or the robot 10b becomes the third robot. However, if the gripping system 1 includes three or more robots 10, the third robot may be determined from among the three or more robots 10.

[0117] Then, the first control unit 51 causes the third robot to release the third object (step S204). That is, the first control unit 51 causes the third robot to release the third object into the container 31 from which the first robot has released the first object. Note that the third object is the same type of object (such as food ingredients) as the first object. The process by which the first control unit 51 causes the third robot to release the third object is the same as the process by which the first control unit 51 causes the first robot to release the first object (step S14), and thus detailed description is omitted.

[0118] When the first control unit 51 determines that the weight value of the first object is equal to or greater than the first predetermined value (NO in step S201), it determines whether the weight value of the first object is greater than the second predetermined value (step S205). The first control unit 51 reads and obtains the weight value of the first object and the second predetermined value from the control data 54a in the storage unit 54, and determines whether the weight value of the first object is greater than the second predetermined value. When the first control unit 51 determines that the weight value of the first object is greater than the second predetermined value (YES in step S205), it causes one of the plurality of robots 10 to grip a part of the first object (step S206). That is, the first control unit 51 causes one of the plurality of robots 10 to grip the first object in the container 31 from which the first robot has released the first object. At this time, the first control unit 51 does not need to cause all the robots 10 to grip a part of the first object, and it is sufficient to cause at least one robot 10 to grip a part of the first object. Further, it is preferable that a robot other than the first robot grips a part of the first object.

[0119] Then, the first control unit 51 determines the fourth robot that has gripped the fourth object whose weight value has become the difference between the weight value of the first object and the second predetermined value among the plurality of robots 10 at the earliest (step S207). The process in which the first control unit 51 determines the fourth robot is the same as the case where the "predetermined range" in the process in which the first control unit 51 determines the first robot is rephrased as the "difference between the weight value of the first object and the second predetermined value", and thus detailed description thereof is omitted. Note that the second predetermined value may be a value within a certain range. That is, the weight value of the fourth object only needs to fall within a certain range. Further, in the present embodiment, since the gripping system 1 includes only two robots 10, either the robot 10a or the robot 10b becomes the fourth robot. However, the gripping system 1 may include three or more robots 10, and the fourth robot may be determined from among the three or more robots 10.

[0120] Then, the first control unit 51 causes the fourth robot to release the fourth object at a position different from the first object (step S208). That is, the first control unit 51 causes the fourth robot to release the fourth object at a position different from the container 31 from which the first robot released the first object. Since the process of the first control unit 51 causing the fourth robot to release the fourth object is the same as the process of the first control unit 51 causing the first robot to release the first object (step S14), a detailed description thereof will be omitted.

[0121] When the first control unit 51 determines that the weight value of the first object is equal to or less than the second predetermined value (NO in step S205), the first control unit 51 ends the process. As described above, the process of the first control unit 51 adjusting the weight of the first object held and released by the first robot (step S15 in FIG. 7) ends.

[0122] [4.4 Explanation of Step S16] Next, a detailed explanation will be given of the process of the first control unit 51 determining the area where the robot 10 holds the object T (step S16 in FIG. 7). FIG. 17 is a flowchart showing the process of the first control unit 51 according to the present embodiment determining the area where the robot 10 holds the object T (step S16 in FIG. 7).

[0123] As shown in FIG. 17, first, the first control unit 51 detects the amount of the object T remaining in the first area within the area R and the amount of the object T remaining in the second area within the area R (step S301). The first area is an area where one of the plurality of robots 10 holds the object T, and the second area is an area where another of the plurality of robots 10 holds the object T. That is, the first control unit 51 causes one of the plurality of robots 10 (for example, robot 10a) to hold the object T (for example, object T1) located in the first area (for example, area R1), and causes another robot 10 (for example, robot 10b) to hold the object T (for example, object T2) located in the second area (for example, area R2).

[0124] For example, the first control unit 51 can detect the amount of the object T remaining in the first area and the amount of the object T remaining in the second area by acquiring the image of the object T remaining in the first area and the image of the object T remaining in the second area. Alternatively, the first control unit 51 can detect the amount of the object T remaining in the first area and the amount of the object T remaining in the second area from the history of the amount of the object T in the first area that one robot 10 has grasped or released and the history of the amount of the object T in the second area that another robot 10 has grasped or released.

[0125] Next, the first control unit 51 determines whether or not a predetermined condition is satisfied (step S302). When it is determined that the predetermined condition is satisfied (YES in step S302), the area for grasping the object is changed (step S303). For example, the first control unit 51 causes one robot 10 to grasp the object T located in the second area under a predetermined condition such that the amount of the object T remaining in the first area decreases or one robot 10 cannot successfully grasp the object T in the first area. Alternatively, the first control unit 51 may cause one robot 10 to grasp the object T located at the boundary between the first area and the second area under the same predetermined condition. The above-mentioned predetermined condition may be appropriately changed according to the situation of the object T or the like.

[0126] When the first control unit 51 determines that the predetermined condition is not satisfied (NO in step S302), the process ends. As described above, the process in which the first control unit 51 determines the area where the robot 10 grasps the object T (step S16 in FIG. 7) ends.

[0127] In addition, when the first control unit 51 determines that the amount of the object T has decreased (the depth has become shallower), the first control unit 51 may cause at least one of the gripping members 100 of the robot 10 to perform a leveling operation for flattening the surface of the object T. The leveling operation is an operation of bringing the tip of the gripping member 100 (the tip in the negative Z-axis direction of the plate-like portion 110) into contact with the surface portion of the object T and moving (reciprocating) the gripping member 100 in the Y-axis direction to flatten the surface of the object T. Alternatively, the first control unit 51 may cause at least one of the gripping members 100 of the robot 10 to perform a scraping operation for gathering the objects T. The scraping operation is an operation of inserting the gripping member 100 into a deep position of the object storage unit 20 and moving it in the Y-axis direction to gather the objects T.

[0128] [Explanation of Step S17 in 4.5] Next, a process in which the first control unit 51 causes each of the plurality of robots 10 to grip a part of the object T again (step S17 in FIG. 7) will be described in detail. The first control unit 51 performs a process of causing all the robots 10 that are not gripping the object T to grip a part of the object T again. Hereinafter, for convenience of explanation, a process of causing the second robot to grip a part of the object T again will be described.

[0129] FIG. 18 is a flowchart showing a process (step S17 in FIG. 7) in which the first control unit 51 according to the present embodiment causes the second robot to grip a part of the object T again.

[0130] As shown in FIG. 18, first, the first control unit 51 determines whether the second robot has grasped a second object whose weight value is outside a predetermined range (step S401). The first control unit 51 reads and acquires the weight value of the second object and the predetermined range from the control data 54a, and determines whether the weight value of the second object is outside the predetermined range. When the first control unit 51 determines that the second robot has grasped a second object whose weight value is outside the predetermined range (YES in step S401), the first control unit 51 causes the second robot to release the second object (step S402). Specifically, the first control unit 51 causes the second robot that has grasped the second object whose weight value is outside the predetermined range to release the second object at the position where it is grasped.

[0131] Then, after the second object is released at the grasped position, the first control unit 51 corrects the depth from the surface of the object T that is estimated to be within the predetermined range when the weight value of the second object becomes within the predetermined range (step S403). The first control unit 51 calculates and corrects the depth from the surface of the object T that is estimated to be within the predetermined range when the weight value of the second object becomes within the predetermined range, based on the process of detecting the shape of the object T in step S152 and the history of the second robot grasping the second object. The first control unit 51 writes the calculated depth into the control data 54a and stores it in the storage unit 54.

[0132] Then, the first control unit 51 inserts the second robot to the corrected depth (step S404). Specifically, the first control unit 51 reads and acquires the depth corrected (calculated) in step S403 from the control data 54a, and inserts the two grasping members 100 of the second robot from the surface of the object T to the depth. Note that the first control unit 51 inserts the second robot at the position where the second robot released the second object in step S402.

[0133] Then, the first control unit 51 causes the second robot to grasp a part of the object T again (step S405). Specifically, the first control unit 51 causes the second robot to grasp a part of the object T again, including at least a part of the second object released in step S402.

[0134] When the first control unit 51 determines that the second robot has grasped a second object whose weight value is within a predetermined range (NO in step S401), the process ends. As described above, the process in which the first control unit 51 causes each of the plurality of robots 10 to grasp a part of the object T again (step S17 in FIG. 7) ends. Note that even when the first control unit 51 determines that the second robot has grasped a second object whose weight value is within a predetermined range (NO in step S401), the first control unit 51 may execute a process of causing the second robot to grasp a part of the object T again (steps S402 to S405).

[0135] [Description of Effects] Next, the effects exhibited by the gripping system 1 in the present embodiment will be described. Note that, although the following describes the effects of the gripping system 1, these effects also apply to the control device 50.

[0136] The control device 50 causes each of the plurality of robots 10 to grasp a part of the object T, and releases the first object, which is the first object whose weight value has become within the predetermined range earliest, from the first robot that has grasped it. In this way, by causing the plurality of robots 10 to compete for grasping the object T having a weight value within the predetermined range, the object T having a weight value within the predetermined range can be grasped and released in a shorter time. Therefore, according to the gripping system 1, it is possible to shorten the time for grasping and releasing the object T.

[0137] If the first robot has a problem or the like and cannot release the first object, if the other robots 10 are caused to grasp the object T again and then released, it will take time. For this reason, the control device 50 does not release the grasped second object from the second robot until the first robot releases the first object. Thereby, even when the first robot has a problem or the like and cannot release the first object, the second robot can release the grasped second object. Therefore, according to the gripping system 1, it is possible to shorten the time for grasping and releasing the object T.

[0138] The control device 50 can cause the second robot to release the second object and grip a part of the object T again, so that the second robot, which is slower than the first robot, can prepare to release the object T into the next container 31. Thereby, according to the gripping system 1, the object T can be released into the next container 31 earlier, so that the time for gripping and releasing the object T can be shortened.

[0139] The control device 50 can cause the second robot, which has gripped a second object whose weight value is outside a predetermined range, to grip a part of the object T again, so that the second robot can prepare to release the object T into the next container 31. Thereby, according to the gripping system 1, the object T can be released into the next container 31 earlier, so that the time for gripping and releasing the object T can be shortened. The control device 50 can cause the second robot to release the second object at the gripped position and grip a part of the object T again including at least a part of the released second object, thereby suppressing the occurrence of unevenness on the surface of the object T. The control device 50 corrects the depth from the surface of the object T, inserts the second robot to the corrected depth, and grips a part of the object T again by the second robot, so that an appropriate amount of the object T can be regripped.

[0140] When the control device 50 determines that the weight value of the first object is smaller than the first predetermined value, it causes the third robot, which has gripped the third object whose weight value has become the difference between the weight value of the first object and the first predetermined value earliest, to release the third object. Thereby, even when the weight value of the first object is within a predetermined range but smaller than a more preferable value (equal to or greater than the first predetermined value), the weight value of the first object can be corrected to be equal to or greater than the first predetermined value in a shorter time. Therefore, according to the gripping system 1, the time for gripping and releasing the object T can be shortened.

[0141] When the control device 50 determines that the weight value of the first object is greater than the second predetermined value, the fourth robot that has grasped the fourth object whose weight value has become the difference between the weight value of the first object and the second predetermined value at the earliest is caused to release the fourth object at a position different from the first object. Thereby, even when the weight value of the first object is within a predetermined range but is greater than a more preferable value (equal to or less than the second predetermined value), the weight value of the first object can be corrected to be equal to or less than the second predetermined value in a shorter time. Therefore, according to the gripping system 1, it is possible to shorten the time for gripping and releasing the object T.

[0142] Under predetermined conditions, the control device 50 causes a first robot 10 that grips the object T located in the first area to grip the object T located in the second area. For example, when the first robot 10 has gripped a large number of objects T in the first area and the number of objects T in the first area has decreased, the control device 50 causes the first robot 10 to grip the object T in the second area. Thereby, the control device 50 can cause the robot 10 to grip the object T relatively evenly. Alternatively, when the first robot 10 cannot grip the object T in the first area well but can grip the object T in the second area, the control device 50 causes the first robot 10 to grip the object T in the second area. Thereby, the control device 50 can cause the first robot 10 to grip the object T efficiently.

[0143] The control device 50 causes the single robot 10 that grips the object T located in the first region to grip the object T located at the boundary between the first region and the second region under a predetermined condition. For example, since the object T at the boundary between the first region and the second region often remains ungripped, when the single robot 10 grips many objects T in the first region and the number of objects T in the first region decreases, the control device 50 causes the single robot 10 to grip the object T at the boundary portion. Thereby, the control device 50 can cause the robot 10 to grip the object T relatively evenly. Alternatively, when the single robot 10 cannot successfully grip the object T in the first region but can grip the object T at the boundary portion, the control device 50 causes the single robot 10 to grip the object T at the boundary portion. Thereby, the control device 50 can cause the single robot 10 to grip the object T efficiently.

[0144] The control device 50 can determine which region's object T the robot 10 should grip by detecting the amount of the object T remaining in the first region and the amount of the object T remaining in the second region. Thereby, the control device 50 can cause the robot 10 to grip the object T relatively evenly or cause the robot 10 to grip the object T efficiently.

[0145] The control device 50 changes the distance L between the two gripping members 100 having the plate-like portion 110 that grips the object T to a third distance different from the first distance during the opening operation and the second distance during the closing operation when the two gripping members 100 grip or release the object T. Thereby, even when the object T is gripped by the two gripping members 100 having the plate-like portion 110, the distance L between the two gripping members 100 can be changed to a more appropriate distance, so that it is possible to suppress the object T from being unnecessarily condensed or damaged. Also, the distance L between the two gripping members 100 can be changed to a more appropriate distance according to the shape and size of the object T. The object T can be applied to various things, such as food ingredients, things that are not food ingredients but are easily deformed or damaged, and things whose shape and size are not determined. Therefore, according to the gripping system 1, the object T can be gripped or released more appropriately.

[0146] Depending on the shape and size of the object T, when the object T cannot fit between the two gripping members 100 at the first distance during the opening operation of the two gripping members 100, or when it is desired to grip more objects T, etc., it may be possible to grip the object T more appropriately by changing the distance L between the two gripping members 100 and then gripping the object T. For this reason, after changing the distance L between the two gripping members 100 to a third distance, the control device 50 moves the two gripping members 100 toward the object T. Thereby, according to the gripping system 1, the object T can be gripped more appropriately.

[0147] When a force in a direction away from the object T is applied to the gripping member 100, it is conceivable that the object T may not fit between the two gripping members 100, or that the gripping member 100 may contact the object T at an inappropriate position depending on the shape of the object T. For this reason, when the control device 50 determines that a force equal to or greater than a predetermined value in a direction away from the object T is applied to at least one of the gripping members 100, the control device 50 widens the distance L between the two gripping members 100 to be greater than the third distance. Thereby, according to the gripping system 1, since the gripping member 100 can be arranged at a more appropriate position, the object T can be gripped more appropriately.

[0148] By the control device 50 changing the distance L between the two gripping members 100 during the closing operation to a third distance greater than the second distance, it is possible to suppress the object T from being deformed or crushed due to the distance L between the two gripping members 100 being made too small. Thereby, according to the gripping system 1, the object T can be gripped more appropriately.

[0149] Since each of the two gripping members 100 has a pair of side plate portions 120 on both sides of the plate-like portion 110, the object T can be gripped by the plate-like portion 110 and the pair of side plate portions 120, so it is easy to grip the object T. In this case, since there are fewer escape routes for the object T and there is a risk of deforming or crushing the object T, the effect of changing the distance L between the two gripping members 100 during the closing operation to a third distance greater than the second distance is high.

[0150] After the control device 50 sets the distance L between the two gripping members 100 during the closing operation to the second distance, and then changes it to a third distance greater than the second distance, when there are many objects T being gripped, some of the objects T can be released to reduce the amount of the objects T. Then, by the control device 50 returning the distance L between the two gripping members 100 to the second distance, an appropriate amount of the objects T can be gripped. Thereby, according to the gripping system 1, the objects T can be gripped more appropriately.

[0151] By the control device 50 changing the distance L between the two gripping members 100 to a third distance according to the size of the container 31, the objects T can be gripped or released more appropriately according to the size of the container 31. Thereby, it is possible to suppress the objects T from protruding from the container 31 or the amount of the objects T relative to the container 31 being too small.

[0152] By the control device 50 changing the distance L between the two gripping members 100 to a third distance according to the objects T, the objects T can be gripped or released (loaded) more appropriately by the two gripping members 100.

[0153] The control device 50 determines the weight value of the object T2 that the two gripping members 100b of the robot 10b grip or release by using the weight value of the object T1 that the two gripping members 100a of the robot 10a grip or release. Thereby, the object T that could not be gripped or released by the robot 10a can be gripped or released by the robot 10b. Therefore, according to the gripping system 1, since the accuracy of the weight value of the object T to be gripped or released can be improved, the object T can be gripped or released more appropriately.

[0154] The control device 50 determines the depth at which the two gripping members 100 are inserted into the object T according to the distance L between the two gripping members 100. Thereby, the control device 50 can change the distance L between the two gripping members 100 according to the shape and size of the object T, and determine the depth at which the two gripping members 100 are inserted into the object T according to the distance L. That is, the control device 50 can also determine the depth at which the two gripping members 100 are inserted into the object T according to the shape and size of the object T even for objects T having various shapes and sizes. Therefore, according to the gripping system 1, the object T can be gripped more appropriately.

[0155] When the control device 50 widens the distance L between the two gripping members 100, by shallowing the depth at which the two gripping members 100 are inserted into the object T, an object T with relatively regular quantity can be gripped. By shallowing the depth at which the two gripping members 100 are inserted into the object T, the time until the gripping member 100 reaches the bottom of the object T can be lengthened. Thereby, the time and man-hours for leveling the object T or replenishing the object T can be reduced. Therefore, the time (tact time) for gripping and releasing the object T and placing the object T in the container 31 can be shortened. By these means, according to the gripping system 1, the object T can be gripped more appropriately.

[0156] When the control device 50 determines that the depth of the object T has become equal to or less than a predetermined value, by widening the distance L between the two gripping members 100, the time until the gripping member 100 reaches the bottom of the object T can be lengthened. Thereby, the time and man-hours for leveling the object T or replenishing the object T can be reduced, and the tact time can be shortened. Therefore, according to the gripping system 1, the object T can be gripped more appropriately.

[0157] When the control device 50 determines that the depth of the object T has become equal to or less than a predetermined value, by causing the gripping member 100 to perform a leveling operation, the surface of the object T can be leveled. As a result, the time until the gripping member 100 reaches the bottom of the object T can be lengthened, so that the tact time can be shortened or the like. Therefore, according to the gripping system 1, the object T can be gripped more appropriately.

[0158] When the control device 50 determines that the depth of the object T has become equal to or less than a predetermined value, by causing the scraping member 100 to perform a scraping operation, the depth of the object T can be increased. As a result, the time until the gripping member 100 reaches the bottom of the object T can be lengthened, so that the tact time can be shortened or the like. Therefore, according to the gripping system 1, the object T can be gripped more appropriately.

[0159] When the control device 50 determines that a force in a direction away from the object T has been applied to the gripping member 100, by determining that the gripping member 100 has come into contact with the object T, it is possible to easily detect that the gripping member 100 has come into contact with the object T.

[0160] When only one gripping member 100 is inserted into the object T after coming into contact with the object T, compared with the case where the two gripping members 100 are inserted into the object T to the same depth after coming into contact with the object T, the amount of the object T gripped by the two gripping members 100 will decrease. For this reason, when the control device 50 determines that only one gripping member 100 has come into contact with the object T, the depth at which the gripping member 100 is inserted into the object T is increased. As a result, it is possible to suppress a decrease in the amount of the object T gripped by the two gripping members 100. Therefore, according to the gripping system 1, the object T can be gripped more appropriately.

[0161] When only one gripping member 100 contacts the object T and then inserts into the object T, the amount of the object T gripped by the two gripping members 100 is less than when the two gripping members 100 contact the object T and then insert into the object T to the same depth. For this reason, when the control device 50 determines that only one gripping member 100 has contacted the object T, the control device 50 widens the distance L between the two gripping members 100. Thereby, it is possible to suppress a decrease in the amount of the object T gripped by the two gripping members 100. Therefore, according to the gripping system 1, the object T can be gripped more appropriately.

[0162] The control device 50 detects the shape of the object T by determining that at least one of the gripping members 100 has contacted the object T. For example, when the control device 50 determines that only one gripping member 100 has contacted the object T, the control device 50 can detect that the object T is on a slope. When the control device 50 determines that the two gripping members 100 have contacted the object T, the control device 50 can detect that the object T is relatively flat. Thus, according to the gripping system 1, by detecting the shape of the object T, the object T can be gripped more appropriately.

[0163] Since the control device 50 is configured to determine the depth at which the two gripping members 100 are inserted into the object T according to the distance L between the two gripping members 100, by determining the distance L between the two gripping members 100 according to the object T, the depth at which the two gripping members 100 are inserted into the object T can be determined according to the object T. Thereby, according to the gripping system 1, the object T can be gripped more appropriately according to the object T.

[0164] For example, when the object T is a food ingredient such as meat and potatoes, by widening the distance L between the two gripping members 100, damage to the food ingredient can be reduced and the appearance can be improved. In particular, when the gripping member 100 includes the plate-shaped portion 110, there is a possibility of cutting the food ingredient, so the effect is high. Also, when the object T is a fragile food ingredient such as a poached egg or scrambled eggs, if the distance L between the two gripping members 100 is wide, it may collapse from the middle when being gripped by the two gripping members 100, or if the two gripping members 100 are closed, the fragile food ingredient may be condensed. Therefore, it is preferable to narrow the distance L between the two gripping members 100. In this way, by determining the distance L between the two gripping members 100 so as not to roughen (not create unevenness) the surface of the object T (food ingredient, etc.) to be gripped, the next gripping accuracy can be improved. As a result, the frequency of depth adjustment of the object T can be reduced, so that the tact time can be shortened, etc. Therefore, according to the gripping system 1, the object T can be gripped more appropriately.

[0165] [Description of Modification Example 6] As described above, the gripping system 1 according to the present embodiment has been described. However, the present invention is not limited to the above embodiment. The embodiments disclosed this time are illustrative in all respects and not restrictive, and the scope of the present invention includes all modifications within the meaning and scope equivalent to the claims.

[0166] In the above embodiment, the object T is assumed to be a food ingredient, but it may be other than a food ingredient. That is, any object T can be applied as long as it can be gripped and released by the two gripping members 100.

[0167] In the above embodiment, the two robots 10 are assumed to have the same configuration, but they may have different configurations.

[0168] In the above-described embodiment, the robot 10 is assumed to have two gripping members 100, but it may have three or more gripping members 100. That is, the robot 10 may grip an object with three or more gripping members 100 (the object is gripped by the opening and closing operations of the three or more gripping members 100). In this case, the "two gripping members 100" such as the "distance between the two gripping members 100" in the above description indicates any two gripping members 100 among the three or more gripping members 100.

[0169] In the above-described embodiment, each of the gripping members 100 included in the robot 10 is assumed to have a plate-like portion 110, a pair of side plate portions 120, and a top plate portion 130. However, any one of the gripping members 100 may not have one or both of the side plate portions 120, or may not have the top plate portion 130. In addition to or instead of the plate-like portion 110, the gripping member 100 may have a non-plate-like member such as a rod shape (column shape) or a block shape.

[0170] In the above-described embodiment, the gripping system 1 is not necessarily limited to including all the above-described components such as the cover portion 40. The control device 50 is not necessarily limited to including all the above-described processing units such as not including the storage unit 54 and acquiring data from an external memory. The control device 50 is not necessarily limited to executing all the above-described steps, and each step executed by the control device 50 is not necessarily performed in the above-described order.

[0171] Furthermore, the present invention can be realized not only as the gripping system 1 and the control device 50, but also as a gripping method or a control method including characteristic processing steps performed by the gripping system 1 or the control device 50. The present invention can be realized as a program that causes a computer to execute steps included in the gripping method or the control method. That is, each component included in the control device 50 may be realized by a program execution unit such as a CPU or a processor reading and executing a software program recorded on a recording medium such as a hard disk or a semiconductor memory. Further, the present invention can be realized as a computer-readable non-transitory recording medium on which the program is recorded, for example, a flexible disk, a hard disk, a CD-ROM, an MO, a DVD, a DVD-ROM, a DVD-RAM, a BD (Blu-ray (registered trademark) Disc), a semiconductor memory, a flash memory, a magnetic storage device, an optical disk, a paper tape, or any other medium. And the program can be distributed via the recording medium and a transmission medium such as the Internet. Also, the present invention can be realized as an integrated circuit including a processing unit included in the control device 50. That is, each functional block of the control device 50 shown in FIG. 6 may be realized as a large-scale integration (LSI) which is an integrated circuit. These may be individually formed into one chip, or may be formed into one chip so as to include part or all of them. Thus, the control device 50 may be configured such that each component is composed of dedicated hardware, or may be realized by executing a software program suitable for each component.

[0172] A form constructed by arbitrarily combining the components included in the above-described embodiment and its modifications is also included in the scope of the present invention.

Explanation of Reference Numerals

[0173] 1 Gripping system 2 Belt conveyor 10, 10a, 10b Robot 11 Hand 12 Robot arm 20 Object storage unit 30 Container supply unit 31 Container 40 Cover part 50 Control device 51 First control unit 52 Second control unit 54 Memory unit 54a Control data 100, 100a, 100b, 101, 101a, 101b, 102, 102a, 102b Gripping members 110, 111, 112 Plate-like parts 120, 121, 122 Side plate parts 130, 131, 132 Top plate parts 200, 201, 202 Moving parts 300 Guide part 400 Connection part

Claims

1. A plurality of robots that hold and release a part of an object, and a control device that controls the operations of the plurality of robots, wherein the control device causes each of the plurality of robots to hold a part of the object, and releases the first object held by the first robot that first holds the first object among the plurality of robots when the weight value of the first object falls within a predetermined range holding system.

2. The control device does not release the second object held by a second robot different from the first robot until the first robot releases the first object The holding system according to claim 1.

3. The control device releases the second object held by a second robot different from the first robot and causes the second robot to hold a part of the object again The holding system according to claim 1 or 2.

4. The control device releases the second object held by the second robot when the weight value of the second object falls outside the predetermined range at the position where the second object is held, and after the second object is released at the held position, corrects the depth from the surface of the object at which the weight value of the second object is estimated to fall within the predetermined range, inserts the second robot to the corrected depth, and causes the second robot to hold a part of the object again including at least a part of the released second object The holding system according to claim 3.

5. When the control device determines that the weight value of the first object is smaller than a first predetermined value, it causes any one of the plurality of robots to hold a part of the object, and releases the third object held by the third robot that first holds the third object among the plurality of robots when the weight value of the third object becomes the difference between the weight value of the first object and the first predetermined value The holding system according to claim 1 or 2.

6. When the control device determines that the weight value of the first object is larger than a second predetermined value, it causes any one of the plurality of robots to hold a part of the first object, and releases the fourth object held by the fourth robot that first holds the fourth object among the plurality of robots when the weight value of the fourth object becomes the difference between the weight value of the first object and the second predetermined value at a position different from the first object The holding system according to claim 1 or 2.

7. The control device causes one of the plurality of robots to hold an object located in the first region, causes another robot to hold an object located in the second region, and causes the one robot to hold the object located in the second region under a predetermined condition. The holding system according to claim 1.

8. The control device causes one of the plurality of robots to hold an object located in the first region, causes another robot to hold an object located in the second region, and causes the one robot to hold the object located at the boundary between the first region and the second region under a predetermined condition. The holding system according to claim 1.

9. The control device detects the amount of the object remaining in the first region and the amount of the object remaining in the second region. The holding system according to claim 7 or 8.

10. A control device that controls the operations of a plurality of robots that hold and release a part of an object, causes each of the plurality of robots to hold a part of the object, and causes the first robot that holds the first object, which is the first object whose weight value first falls within a predetermined range among the plurality of robots, to release the first object. Control device.

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