Robot hand and item pick-up system

Abstract

To provide a robot hand of an article takeout system which can hold an article taken out from an article placement part after its attitude is changed to a target attitude with a simple structure.SOLUTION: A robot hand includes: a pickup part 41 which separately takes out an article 10 from an article group 10W placed on an article placement part 2 and holds the article 10 in a releasable state; and an article holding part 42 which has a storage groove T immediately below the pickup part 41 and receives the article 10 in the storage groove T when the pickup part 41 releases the article 10. The article holding part 42 includes: an attitude change part 42x which utilizes external force acting on the article 10 in a non-contact manner to cause the article 10 to roll in the storage groove T when the article holding part 42 receives the article 10 in the storage groove T and restricts rolling of the article 10 in the storage groove T at that time to change an attitude of the article 10 to a target attitude; and a holding part 42y which holds the article 10 whose attitude is changed to the target attitude in the storage groove T.SELECTED DRAWING: Figure 4

Description

[Technical field]

[0001] The present disclosure relates to a robot hand and an article picking system. [Background technology]

[0002] Conventionally, an item picking system using an industrial robot is known in which a large number of items randomly stacked on an item placement section (e.g., inside an item storage box) are recognized by an imaging section (e.g., a camera device), and the robot hand is used to grasp and transport each item, and then place it in a specific posture on a specified installation target. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2017-052094 A Summary of the Invention [Problem to be solved by the invention]

[0004] In this type of item picking system, when an item is picked individually from a pile of bulk items, it is required to place the item accurately without misalignment and with the correct posture. However, in a pile of bulk items, the posture of each item is random, and the item to be picked may overlap or touch other items, making it difficult for the robot hand to pick it up properly.

[0005] Against this background, for example, Patent Document 1 proposes an article-taking system that uses gravity to change the posture of an article that has been grasped in a robot hand. The article-taking system in Patent Document 1 describes a method of grasping a position where a moment is generated in the article and rotating the article by changing the gripping force of the robot hand.

[0006] However, in the method described in Patent Document 1, since the posture of the article is changed while sliding the article in the robot hand, the gripping force needs to be delicately controlled when changing the posture of the article, which causes a problem that the control of the robot hand and the robot arm becomes complicated. In addition, this method has a problem that the gripping position of the article is easily shifted, which causes a variation in the placement position when placing the article.

[0007] The present disclosure has been made in consideration of the above-mentioned problems, and aims to provide a robot hand and an item removal system that have a simple configuration and are capable of holding an item removed from an item loading section after changing its posture to a target posture. [Means for solving the problem]

[0008] The present disclosure, which solves the above-mentioned problems, is a pickup unit that picks up an individual article from a group of articles placed on the article placement unit and holds the article in a releasable state; an article holding section having a storage groove directly below the pickup section, the article holding section receiving the article in the storage groove when the pickup section releases the article; The article holding portion is a posture changing unit that, when receiving the object in the storage groove, rolls the object in the storage groove by utilizing an external force acting on the object in a non-contact manner, and changes the object to a target posture by regulating the rolling manner of the object in the storage groove; a gripping portion that grips the article that has been changed to the target posture in the storage groove, This is a robot hand for an article pick-up system.

[0009] In other respects, An article picking system having the above robot hand. Effect of the Invention

[0010] According to the robot hand of the present disclosure, with a simple configuration, it is possible to hold an article taken out from an article placement section after changing its posture to a target posture. [Brief description of the drawings]

[0011] [Figure 1] FIG. 1 is a diagram showing an overall configuration of an article pick-up system according to a first embodiment; [Diagram 2] FIG. 1 is a diagram showing a configuration of a control system of an article pickup system according to a first embodiment; [Diagram 3] FIG. 1 is a diagram showing an article to be picked up by the article pick-up system according to the first embodiment; [Figure 4] FIG. 1 is a diagram showing a configuration of a robot hand according to a first embodiment; [Diagram 5] FIG. 1 is a diagram showing the configuration of an item holding portion (accommodation groove) of a robot hand according to a first embodiment; [Figure 6] FIG. 1 is a diagram showing an example of a manner in which an article rolls in a storage groove formed by an article holding portion of a robot hand according to a first embodiment; [Figure 7] 1 is a flowchart showing an example of a process performed by a control unit when operating a robot hand according to a first embodiment. [Figure 8] FIG. 13 is a diagram showing an example of the configuration of a robot hand according to a second embodiment. [Figure 9] FIG. 13 is a diagram showing the configuration of an item holding portion (accommodation groove) of a robot hand according to a second embodiment; [Figure 10] FIG. 13 is a diagram showing an example of a manner in which an article rolls in a storage groove formed by an article holding portion of a robot hand according to a second embodiment; [Figure 11] 10 is a flowchart showing an example of a process performed by a control unit when operating a robot hand according to a second embodiment. [Figure 12] FIG. 13 is a diagram showing an example of the configuration of a robot hand according to a third embodiment. [Figure 13] FIG. 13 is a diagram showing an example of a manner in which an article rolls in a storage groove formed by an article holding portion of a robot hand according to a third embodiment; [Figure 14]13 is a flowchart showing an example of a process performed by a control unit when operating a robot hand according to a third embodiment. [Figure 15] FIG. 13 is a diagram showing an example of the configuration of a robot hand according to a fourth embodiment. [Figure 16] FIG. 13 is a diagram showing an example of a manner in which an article rolls in a storage groove formed by an article holding portion of a robot hand according to a fourth embodiment; [Figure 17] FIG. 13 is a diagram showing an example of the configuration of a robot hand according to a fifth embodiment. [Figure 18] FIG. 13 is a diagram showing an example of a manner in which an article rolls in a storage groove formed by an article holding portion of a robot hand according to a fifth embodiment; [Figure 19] 13 is a flowchart showing an example of a process performed by a control unit when operating a robot hand according to a fifth embodiment. [Figure 20] FIG. 13 is a diagram showing an example of the configuration of a robot hand according to a sixth embodiment. [Figure 21] FIG. 13 is a diagram showing an example of the configuration of a robot hand according to a sixth embodiment. [Figure 22] FIG. 13 is a diagram for explaining the operation of a robot hand according to the seventh embodiment. [Figure 23] FIG. 13 is a diagram for explaining the operation of a robot hand according to the seventh embodiment. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0012] Hereinafter, preferred embodiments of the present disclosure will be described in detail with reference to the accompanying drawings. In this specification and the drawings, components having substantially the same functions are denoted by the same reference numerals, and redundant description will be omitted.

[0013] In addition, in each drawing, unless otherwise specified, the upward direction in the drawing represents the vertical upward direction, the downward direction in the drawing represents the vertical downward direction, and the horizontal direction in the drawing represents the horizontal direction. In the following description, the upward direction in the drawing will be referred to as the "upward direction", the downward direction in the drawing will be referred to as the "downward direction", and the horizontal direction in the drawing will be referred to as the "horizontal direction".

[0014] (First embodiment) <Overall configuration of the item pick-up system> Hereinafter, a configuration of an article pick-up system according to one embodiment of the present invention will be described with reference to FIGS.

[0015] Fig. 1 is a diagram showing an overall configuration of an article pick-up system 1 according to the present embodiment. Fig. 2 is a diagram showing a configuration of a control system of the article pick-up system 1 according to the present embodiment. Fig. 3 is a diagram showing an article 10 to be picked up by the article pick-up system 1 according to the present embodiment.

[0016] The item removal system 1 of this embodiment is a system for removing items 10 (i.e., workpieces) that are bulk-stacked on an item loading section 2 (e.g., a container), holding and transporting the removed items 10, and placing them in an aligned state on the installation target 20.

[0017] In the article take-out system 1 according to this embodiment, the bolt member is the article 10 (hereinafter simply referred to as "article 10") to be taken out from the article placement section 2. The article 10 (bolt member) has a long and thin leg 10a and a head 10b formed at one end of the leg 10a and wider than the leg 10a. The installation target 20 is formed with, for example, a plurality of holes 21 through which the legs 10a of the article 10 can be inserted. After taking out the article 10 from the article placement section 2, the article take-out system 1 changes the position of the article 10 to a position corresponding to the hole shape of the hole 21 of the installation target 20, and then installs the article 10 in the hole 21 of the installation target 20.

[0018] In this embodiment, the target posture of the article 10 is one in which the head 10b faces upward and the legs 10a faces downward in accordance with the shape of the hole 21 of the installation target 20 (hereinafter simply referred to as the "target posture").

[0019] The article pickup system 1 includes a robot arm 30, a robot hand 40, an imaging unit 50, and a control unit 60.

[0020] <Imaging unit> The imaging unit 50 is, for example, a camera device that captures an image of the group of articles 10W placed on the article placement section 2 and outputs image data obtained by the imaging to the control unit 60. Note that the imaging unit 50 performs imaging multiple times while shifting the imaging position so that the position and orientation of the articles 10 placed on the article placement section 2 in three-dimensional space can be detected from the image data. The imaging unit 50 may also be configured with an imaging device capable of acquiring distance data from the imaging unit 50 to the articles 10, such as a stereo camera or a radar device.

[0021] The imaging unit 50 may also be disposed so as to be able to capture an image of the article 10 held by the robot hand 40. This makes it possible to detect the state of the article 10 held by the robot hand 40 (i.e., the position and posture of the article 10 in the storage groove T, which will be described later) from image data obtained by imaging by the imaging unit 50.

[0022] <Control Unit> The control unit 60 is, for example, a microcomputer including a CPU (Central Processing Unit), a ROM (Read Only Memory), a RAM (Random Access Memory), an input port, an output port, etc. The control unit 60 communicates with each unit (the robot arm 30, the robot hand 40, and the imaging unit 50) of the article pickup system 1 to control them and receive data from them.

[0023] The control unit 60, for example, acquires image data from the imaging unit 50, and detects the position and orientation in three-dimensional space of one or more articles 10 among the group of articles 10W placed on the article placement unit 2 based on the image data. Then, the control unit 60 determines, for example, the article 10 located at the top of the group of articles 10W placed on the article placement unit 2 as the article to be removed, and controls the robot arm 30 and the robot hand 40 based on the position and orientation of the article 10. That is, through such control, the control unit 60 causes the robot hand 40 to hold the article 10 and place the held article 10 in the hole 21 of the placement target 20.

[0024] <Robot arm> The robot arm 30 is, for example, a vertical articulated robot arm, and changes the position and orientation of the robot hand 40 in three dimensions.

[0025] The robot arm 30 includes, for example, a base 31 placed on a floor surface or the like, a plurality of links 32 connected in series to the base 31, a plurality of joints 33 provided at the connecting portions, and a plurality of joint motors 34 (see FIG. 2) that drive the joints 33.

[0026] <Robot hand> The robot hand 40 is provided at the tip of the robot arm 30 via a joint 33, and picks up the articles 10 one by one from the group of articles 10W placed on the article placement unit 2, and holds the articles 10. Then, the robot hand 40 changes the posture of the article 10 to a target posture (a posture in which the head 10b of the article 10 faces upward and the leg 10a of the article 10 faces downward), and then carries the article 10 to the installation target 20 and places the article 10 in the hole 21 of the installation target 20.

[0027] Fig. 4 is a diagram showing the configuration of a robot hand 40 according to this embodiment. Fig. 4A to Fig. 4C show the state of each part in chronological order from when the robot hand 40 picks up an item 10 to when the item 10 is gripped.

[0028] Fig. 5 is a diagram showing the configuration of the article holding part 42 (storage groove T) of the robot hand 40 according to this embodiment. Fig. 5A is a diagram showing the article holding part 42 as viewed diagonally from above, Fig. 5B is a diagram showing the article holding part 42 as viewed from above, and Fig. 5C is a diagram showing the article holding part 42 as viewed from the side. Note that Fig. 5C shows a state in which an article 10 is gripped by the article holding part 42.

[0029] Fig. 6 is a diagram showing an example of a manner in which the article 10 rolls in the storage groove T formed by the article holding part 42 of the robot hand 40 according to this embodiment. Fig. 6A to Fig. 6E show an example of a manner in which the article 10 rolls in time series from when the article 10 is dropped from the pickup part 41 into the storage groove T of the article holding part 42 until it is grasped by the article holding part 42.

[0030] The robot hand 40 includes a pickup unit 41, an item holding unit 42, and a sensor unit 43 (see FIGS. 2 and 4).

[0031] The pickup unit 41 is, for example, an air-type or magnetic-type suction head, and picks up the article 10 individually from the group of articles 10W placed on the article placement unit 2 (hereinafter referred to as a "picking operation") (see FIG. 4A). The pickup unit 41 then holds the article 10 in a releasable state. The suction head can generate a suction force at the head tip (i.e., the nozzle tip) to suction one surface (e.g., the upper surface) of the article 10 located at a position opposite the suction head, and hold the article 10, so that the article 10 can be picked up individually without being affected by differences in the posture of the article 10. The pickup unit 41 is, for example, configured in a nozzle shape, and extends downward from the center position of the hand base 40T attached to the tip of the robot arm 30. The pickup unit 41 may be configured to be movable up and down.

[0032] The group of articles 10W placed on the article placement section 2 is in a bulk state, and each article 10 is placed in various postures. From this viewpoint, the robot hand 40 according to this embodiment is configured to first individually pick up the articles 10 placed in various postures from the article placement section 2 at the pickup section 41.

[0033] The picking operation of the pickup unit 41 is executed under the control of the control unit 60. For example, the control unit 60 determines the approach posture of the pickup unit 41 with respect to the item 10 based on the position and posture in three-dimensional space of the item 10 to be picked up, and operates the robot arm 30 according to the approach posture. Then, when the pickup unit 41 faces the item 10, the control unit 60 causes the pickup unit 41 to hold the item 10 by generating a suction force on the pickup unit 41. Then, when the item holding unit 42 forms a storage groove T directly below the pickup unit 41, the control unit 60 causes the pickup unit 41 to release the holding state of the item 10 (see FIG. 4B).

[0034] The article holding unit 42 forms a storage groove T directly below the pickup unit 41, and receives the article 10 dropped from the pickup unit 41 in the storage groove T. The article holding unit 42 changes the article 10 to a target posture by regulating the rolling behavior of the article 10 in the storage groove T (see FIG. 6) using an external force (here, gravity) acting on the article 10 without contact, and then grasps the article 10 that has been changed to the target posture. Note that the article pick-up system 1 according to this embodiment is configured to regulate the rolling behavior of the article 10 in the storage groove T using gravity acting on the article 10, but the external force for regulating the rolling behavior of the article 10 may be another external force, such as a magnetic force, a centrifugal force, an inertial force, or a fluid pressure (see, for example, the third to sixth embodiments described later).

[0035] The article holding section 42 is composed of, for example, a pair of gripping members 42A, 42B arranged in a pair below the hand base 40T. The storage groove T is formed in the spatial region between the gripping members 42A and 42B by butting the opposing surfaces of the gripping members 42A and 42B, which have uneven shapes. The left gripping member 42A and the right gripping member 42B of the pair of gripping members 42A, 42B are arranged on the left and right of the pickup section 41, respectively.

[0036] The pair of gripping members 42A, 42B are connected to a gripping member drive mechanism that adjusts the lateral distance between the left gripping member 42A and the right gripping member 42B (hereinafter referred to as the "inter-member distance"), and performs opening and closing operations under the control of the control unit 60. The gripping member drive mechanism may have any configuration, and is, for example, configured by a link mechanism driven by a motor or a cylinder. In the following, the operation of bringing gripping member 42A and gripping member 42B close to each other is referred to as the "closing" operation, and the operation of moving gripping member 42A and gripping member 42B away from each other is referred to as the "opening" operation.

[0037] The general operation of the article pick-up system 1 is as follows (see FIG. 4), for example.

[0038] First, the article pickup system 1 performs a picking operation of the article 10 using the pickup unit 41. In this stage, the article pickup system 1 holds the pair of gripping members 42A, 42B in a state where they are lifted above the lower end of the pickup unit 41 (i.e., in an open state) so that the lower end of the pickup unit 41 protrudes downward (see FIG. 4A).

[0039] Next, the article taking out system 1 controls the pair of gripping members 42A, 42B to operate in the "closed side", and the opposing surface of the left gripping member 42A and the opposing surface of the right gripping member 42B butt against each other to form a storage groove T for receiving the article 10 directly below the pickup unit 41. Then, the article taking out system 1 causes the pickup unit 41 to release the holding state of the article 10, and causes the article holding unit 42 to receive the article 10 that falls from the pickup unit 41 in the storage groove T (see FIG. 4B). At this time, the article 10 rolls along the groove shape of the storage groove T due to an external force (here, gravity) acting on the article 10 without contact, changes to a target posture, and is positioned at a predetermined position (fitting groove Tb shown in FIG. 5C) in the storage groove T (described later with reference to FIG. 6).

[0040] Next, in a state where the article 10 is positioned in the storage groove T by the article holding section 42 in a target posture, the article take-out system 1 controls the pair of gripping members 42A, 42B to further move to the "closed side" to cause the pair of gripping members 42A, 42B to grip the article 10 in the storage groove T (see FIG. 4C). Note that the "gripped state" referred to here means a state where the pair of gripping members 42A, 42B clamp and fix the article 10 (the same applies below). In the article take-out system 1 according to this embodiment, the article 10 is held in a gripped state (i.e., fixed state) in the storage groove T, thereby stabilizing the holding state of the article 10, and then, it becomes possible to insert the article 10 into the hole 21 of the installation target 20.

[0041] Here, the detailed configuration of the article holding portion 42 will be described with reference to Figs.

[0042] The item holding section 42 has a posture change section 42x that, when receiving the item 10 in the storage groove T, uses an external force acting on the item 10 without contact to roll the item 10 within the storage groove T and regulates the rolling manner of the item 10 within the storage groove T at that time, thereby changing the item 10 to a target posture, and a gripping section 42y that grips the item that has been changed to the target posture within the storage groove T.

[0043] In this embodiment, the posture changing section 42x is formed in an area (here, an area on the top surface of the storage groove T) (hereinafter referred to as the "receiving area") where the article 10 dropping from the pickup section 41 in the storage groove T first lands, and includes a guide groove Ta that guides the article 10 from the receiving area to the fitting groove Tb. The gripping section 42y is formed in an area guided by the guide groove Ta in the storage groove T, and includes a fitting groove Tb that positions the article 10 whose posture has been changed to the target posture. The gripping section 42y grips the article 10 in the fitting groove Tb by pinching the article 10 positioned in the fitting groove Tb from both sides.

[0044] In other words, in this embodiment, when the opposing surfaces of the gripping members 42A and 42B are butted against each other, the guide groove Ta and the fitting groove Tb formed in the spatial region between them form the storage groove T. The storage groove T according to this embodiment has a groove structure that uses gravity to roll the article 10 from above to below, and has a guide groove Ta in the region where the article 10 dropping from the pickup unit 41 of the storage groove T first lands, and a fitting groove Tb directly below the guide groove Ta.

[0045] More specifically, the guide groove Ta has an inclined surface Taa and a posture change guide hole Tab (see Figs. 5A and 5B). Note that the guide groove Ta according to this embodiment has a structure in which, for example, in a plan view, the posture change guide hole Tab is formed vertically so as to divide the guide groove Ta into two at the center, and the inclined surfaces Taa are formed adjacent to both sides of the posture change guide hole Tab.

[0046] The inclined surface Taa is inclined with respect to the horizontal direction, and has a surface shape that restricts the movement direction of the article 10 that lands on the inclined surface Taa so that the article 10 rolls toward the posture change guide hole Tab due to the action of gravity. More specifically, the inclined surface Taa restricts the rolling manner of the article 10 so that the longitudinal direction of the article 10 is aligned with the formation direction of the posture change guide hole Tab.

[0047] The posture change guide hole Tab changes the posture of the article 10 guided from the inclined surface Taa to a target posture (here, a posture in which the head 10b of the article 10 faces upward and the legs 10a face downward). The posture change guide hole Tab has a hole shape (for example, a through hole having a width larger than the width of the legs 10a and smaller than the width of the head 10b) through which only the legs 10a of the article 10 can pass and the head 10b of the article 10 cannot pass, and is configured such that the head 10b of the article 10 guided from the inclined surface Taa to the posture change guide hole Tab gets caught at the entrance of the posture change guide hole Tab and only the legs 10a fall into the posture change guide hole Tab by the action of gravity. As a result, the article 10 is guided to change its posture to one in which the head 10b faces upward and the legs 10a face downward while passing through the posture change guide hole Tab.

[0048] After the article 10 has been changed to the target posture by the posture change guide hole Tab, the head 10b of the article 10 caught at the entrance of the posture change guide hole Tab is released from the caught state by, for example, promoting forced movement by opening the pair of gripping members 42A, 42B or applying vibration to the pair of gripping members 42A, 42B using the robot arm 30, and the head 10b is moved further toward the fitting groove Tb (here, the lower side of the storage groove T).

[0049] The fitting groove Tb has a shape that fits with the article 10 that has been changed to the target posture (a posture in which the head 10b of the article 10 faces upward and the legs 10a face downward), and positions the article 10 in the target posture by fitting with the article 10. Note that the fitting groove Tb according to this embodiment is formed directly below the posture change guide hole Tab, and the article 10 that has been changed to the target posture by the posture change guide hole Tab falls downward in the same posture due to the action of gravity, thereby fitting into the fitting groove Tb.

[0050] At the lower end side of the fitting groove Tb, a through hole Tbb (see FIG. 5C) is formed through which the leg portion 10a of the article 10 can be inserted so that the leg portion 10a of the article 10 protrudes downward from the fitting groove Tb. In other words, when the article 10 is fitted into the fitting groove Tb, the leg portion 10a protrudes downward from the through hole Tbb of the fitting groove Tb, and the head portion 10b is held in the fitting groove Tb in a state in which the leg portion 10a is in contact with the bottom and side surfaces of the fitting groove Tb.

[0051] The movement of the article 10 from the posture change guide hole Tab to the fitting groove Tb is induced, for example, by the opening and closing operation of the pair of gripping members 42A, 42B. For example, by slightly expanding the distance between the pair of gripping members 42A, 42B, the article 10 can be moved from the posture change guide hole Tab to the fitting groove Tb by the action of gravity. On the other hand, the movement of the article 10 may be promoted by applying vibration to the article holding unit 42 using the robot arm 30, so that the article 10 is guided from the posture change guide hole Tab to the fitting groove Tb. These operations are performed under the control of the control unit 60.

[0052] The behavior of the article 10 that has fallen into the storage groove T is as shown in Figs. 6A to 6E.

[0053] The article 10 released from the holding state by the pickup unit 41 first lands in the guide groove Ta. Then, the article 10 that has landed in the guide groove Ta rolls along the inclined surface Taa in the guide groove Ta due to the action of gravity (FIG. 6A). At this time, the rolling manner of the article 10 is restricted by the inclined surface Taa, and the article 10 is guided to the posture change guide hole Tab so that its longitudinal direction is aligned with the longitudinal direction of the posture change guide hole Tab (FIG. 6B). Since the head 10b of the article 10 cannot pass through the posture change guide hole Tab, the leg 10a of the article 10 falls below the posture change guide hole Tab, and the head 10b of the article 10 gets caught in the posture change guide hole Tab, and the posture of the article 10 is changed to a state in which the leg 10a faces downward and the head 10b faces upward (FIG. 6C). In this state, the distance between the pair of gripping members 42A, 42B is slightly increased, and the article 10 fits into the fitting groove Tb with the legs 10a facing downward and the head 10b facing upward (FIG. 6D). Thereafter, under the control of the control unit 60, the pair of gripping members 42A, 42B are operated in the closing direction, whereby the article 10 is gripped in the fitting groove Tb (FIG. 6E).

[0054] The sensor unit 43 detects that the article 10 is fitted into the fitting groove Tb (see FIG. 4C). The sensor unit 43 is, for example, configured as a light transmission type object detection sensor in which a light emitting unit and a light receiving unit are arranged to face each other with the fitting groove Tb therebetween.

[0055] By providing the sensor unit 43, it is possible to detect that the article 10 released from the pickup unit 41 becomes stuck midway while moving to the fitting groove Tb in the storage groove T. In other words, this makes it possible to retry the rolling motion of the article 10 as necessary. The rolling motion of the article 10 can be retried, for example, by controlling the robot arm 30 to tilt the storage groove T of the article holding unit 42, moving the article 10 in a direction different from when it was dropped into the guide groove Ta, and then returning the position of the article holding unit 42 to its original position (for example, the position of the article holding unit 42 to the horizontal direction).

[0056] <Example of item pick-up system operation> Next, a description will be given of an example of the operation of the article pick-up system 1. The article pick-up system 1 according to this embodiment operates under the control of the control unit 60.

[0057] FIG. 7 is a flowchart showing an example of a process performed by the control unit 60 when operating the robot hand 40 according to this embodiment.

[0058] In step S1, the control unit 60 causes the imaging unit 50 to capture an image of the group of articles 10W placed on the article placement section 2. The control unit 60 then acquires image data from the imaging unit 50 and recognizes the state of the group of articles 10W placed on the article placement section 2 using the image data. At this time, the control unit 60 determines, for example, based on the positions of each article 10 in the group of articles 10W, one article 10 that is easy to remove from the group of articles 10W (for example, the article 10 located at the top of the group of articles 10W) ​​as the item to be removed, and detects the position and attitude of the article 10.

[0059] In step S2, the control unit 60 controls the robot arm 30 to bring the robot hand 40 closer to the article 10 determined to be picked up in step S1. Then, the control unit 60 generates a suction force in the pickup unit 41, causing the pickup unit 41 to adsorb the upper surface of the article 10, and after the pickup unit 41 holds the article 10, the control unit 60 causes the robot hand 40 to retreat from the article placement unit 2 (FIG. 4A).

[0060] In step S3, the control unit 60 closes the pair of gripping members 42A, 42B of the article holding unit 42 to form a storage groove T directly below the pickup unit 41. The control unit 60 adjusts the inter-member distance between the pair of gripping members 42A, 42B based on, for example, a preset size of the article 10.

[0061] In step S4, the control unit 60 causes the pickup unit 41 to release the article 10, and causes the article 10 to drop from the pickup unit 41 into the storage groove T formed by the article holding unit 42 (FIG. 4B). At this time, the article 10 lands in the area of ​​the guide groove Ta in the storage groove T, and naturally moves from the guide groove Ta to the fitting groove Tb due to the action of gravity. Note that in this step S4, the control unit 60 may, for example, perform control to slightly increase the inter-member distance between the pair of gripping members 42A, 42B or to apply vibration to the pair of gripping members 42A, 42B after a predetermined time has elapsed after causing the pickup unit 41 to release the article 10, in order to promote the movement of the article 10 from the posture change guide hole Tab of the guide groove Ta to the fitting groove Tb.

[0062] In step S5, the control unit 60 determines whether or not the article 10 has been fitted into the fitting groove Tb and changed to the target posture based on the sensor signal from the sensor unit 43 after a predetermined time has elapsed since the pickup unit 41 released the article 10 in step S4. If the article 10 has changed to the target posture (S5: YES), the control unit 60 proceeds to step S7, and if the article 10 has not changed to the target posture (S5: NO), the control unit 60 proceeds to step S6.

[0063] In step S6, the control unit 60 causes the article 10 to retry the rolling motion. In this step S6, the control unit 60 temporarily tilts the storage groove T of the article holding unit 42 so that the article 10 moves in a direction opposite to the direction in which the article 10 is expected to move in the guide groove Ta, and then returns the article holding unit 42 to its original position (for example, the position of the article holding unit 42 is horizontal). This eliminates the state in which the article 10 was caught midway before fitting into the fitting groove Tb. The control unit 60 then returns to step S5 again and determines whether the article 10 has changed to the target position based on the sensor signal from the sensor unit 43.

[0064] In step S7, the control unit 60 controls the pair of gripping members 42A, 42B to further narrow the inter-member distance, causing the pair of gripping members 42A, 42B to grip the article 10 fitted in the fitting groove Tb.

[0065] In step S8, the control unit 60 causes the robot arm 30 to move the robot hand 40, and transports the article 10 held by the robot hand 40 from the article placement unit 2 to above the hole 21 of the installation target 20. The control unit 60 then inserts the leg 10a of the article 10 into the hole 21 of the installation target 20, and thereafter opens the pair of gripping members 42A, 42B to release the article 10 from its holding state by the pair of gripping members 42A, 42B. As a result, the article 10 is installed on the installation target 20 with the leg 10a accommodated in the hole 21 and the head 10b abutting against the periphery of the opening of the hole 21.

[0066] In step S9, the control unit 60 refers to the image data obtained from the imaging unit 50 and determines whether removal of all of the articles 10 from the article placement unit 2 has been completed. If removal of all of the articles 10 has been completed (S9: YES), the control unit 60 ends the series of operations in the flowchart of Fig. 7. On the other hand, if removal of all of the articles 10 has not been completed (S9: NO), the control unit 60 returns to step S1, determines the next article 10 to be removed from the group of articles 10W placed on the article placement unit 2, and performs the same process.

[0067] In the item pick-up system 1 of this embodiment, by performing the operations described above, it is possible to individually pick up items 10 from the group of items 10W placed on the item placement section 2 and place them in an aligned state on the installation target 20.

[0068] [effect] As described above, the robot hand 40 according to this embodiment has the following features: A pickup unit 41 that individually picks up an article 10 from a group of articles 10W placed on the article placement unit 2 and holds the article 10 in a releasable state; a storage groove T is formed directly below the pickup section 41, and an article holding section 42 is provided for receiving the article 10 in the storage groove T when the pickup section 41 releases the article 10; The article holding unit 42 is a posture changer 42x that, when receiving the article 10 in the storage groove T, rolls the article 10 in the storage groove T by utilizing an external force acting on the article 10 in a non-contact manner, and changes the article 10 to a target posture by regulating the rolling manner of the article 10 in the storage groove T at that time; and a gripping portion 42y that grips the article 10 that has been changed to the target posture in the storage groove T.

[0069] Therefore, the robot hand 40 according to this embodiment is capable of, with a simple configuration, picking up the article 10 placed in various postures, changing the posture to a target posture, and gripping the article. In particular, the robot hand 40 according to this embodiment is capable of suppressing deviations in the gripping position of the article 10, thereby reducing uncertainties in the movement of the article 10 and being useful in that it is possible to simplify the control of the robot hand 40. This also makes it possible to suppress variations in the placement position when placing the article 10 on the installation target 20.

[0070] Second embodiment Next, the configuration of an article pick-up system 1 according to a second embodiment will be described with reference to FIGS.

[0071] Fig. 8 is a diagram showing an example of the configuration of a robot hand 40 according to the second embodiment. Fig. 8A to Fig. 8D show the states of each part in chronological order from when the robot hand 40 picks up an article 10 to when the article 10 is gripped.

[0072] FIG. 9 is a diagram showing the configuration of an item holding portion 42 (storage groove T) of a robot hand 40 according to the second embodiment.

[0073] Fig. 10 is a diagram showing an example of a manner in which the article 10 rolls in the storage groove T formed by the article holding unit 42 of the robot hand 40 according to the second embodiment. Note that Fig. 10A to Fig. 10E show an example of a manner in which the article 10 rolls in time series from when the article 10 is dropped from the pickup unit 41 into the storage groove T of the article holding unit 42 until when the article 10 is fitted into the fitting groove Tb.

[0074] The article taking system 1 according to this embodiment differs from the article taking system 1 according to the first embodiment in that the robot arm 30 controls the inclination angle of the storage groove T with respect to the vertical direction in order to regulate and promote the movement of the article 10 that has dropped into the storage groove T. In other words, in the article taking system 1 according to this embodiment, the external force caused by gravity acting on the article 10 as it rolls in the storage groove T is controlled in accordance with the position of the article 10, thereby regulating the movement of the article 10 within the storage groove T. Note that a description of the configuration common to the first embodiment will be omitted (the same applies to the other embodiments below).

[0075] The operation of the article pick-up system 1 according to this embodiment is, for example, as follows.

[0076] First, the article pickup system 1 first performs a picking operation of the article 10 using the pickup unit 41. In this stage, the article pickup system 1 holds the pair of gripping members 42A, 42B in a state where they are lifted above the lower end of the pickup unit 41 (i.e., in an open state) so that the lower end of the pickup unit 41 protrudes downward (see FIG. 8A).

[0077] Next, the article take-out system 1 controls the pair of gripping members 42A, 42B to operate in the "closed side," and the opposing surfaces of the left gripping member 42A and the right gripping member 42B are butted together to form a storage groove T for receiving the article 10 directly below the pickup unit 41. Then, the article take-out system 1 causes the pickup unit 41 to release the holding state of the article 10, and causes the article 10 dropped from the pickup unit 41 to be received in the storage groove T formed by the article holding unit 42 (see FIG. 8B). In this embodiment, the state of the storage groove T when receiving the article 10 dropped from the pickup unit 41 is referred to as the "horizontal state," and the state in which the storage groove T is tilted 90 degrees vertically from this horizontal state is referred to as the "vertical state."

[0078] Next, the article take-out system 1 tilts the article holder 42 in stages so that the storage groove T changes from a horizontal state to a vertical state in stages (FIG. 8C). As a result, the article 10 rolls along the groove shape of the storage groove T due to an external force (here, gravity) acting on the article 10 without contact, changes to a target posture, and is positioned at a predetermined position (the fitting groove Tb shown in FIG. 9) in the storage groove T.

[0079] Next, the article pickup system 1 further operates the pair of gripping members 42A, 42B to the "closing side" to grip the article 10 positioned in the storage groove T (see FIG. 8D).

[0080] The article take-out system 1 according to this embodiment employs a structure of the storage groove T suitable for controlling the movement of the article 10 from the guide groove Ta to the fitting groove Tb by variably controlling the external force acting on the article 10.

[0081] Specifically, the storage groove T according to this embodiment has the guide groove Ta and the fitting groove Tb in the same curved rolling surface, and the groove formation direction of the guide groove Ta and the groove formation direction of the fitting groove Tb are configured to face in different directions (for example, they are perpendicular to each other) (see FIG. 9). That is, the storage groove T according to this embodiment is formed so that when the article 10 dropped from the pickup unit 41 is received in the storage groove T, the groove formation direction of the guide groove Ta faces the vertical direction (i.e., the article receiving area of ​​the guide groove Ta becomes a horizontal plane) (see FIGS. 10A and 10B), and when the article pick-up system 1 changes the inclination angle of the article holding unit 42 from the angle at which the storage groove T is formed, the groove formation direction of the fitting groove Tb faces the vertical direction. Also, the storage groove T according to this embodiment is formed so that the posture change guide hole Tab and the fitting groove Tb are communicated with each other.

[0082] The article 10 rolls in the storage groove T in the article pickup system 1 according to this embodiment as follows.

[0083] The article 10 first lands on the guide groove Ta from the pickup unit 41 (see FIG. 10A), and rolls along the groove shape of the guide groove Ta toward the position change guide hole Tab (see FIG. 10B). As the article take-out system 1 tilts the storage groove T vertically, the article 10 moves toward the position change guide hole Tab of the guide groove Ta, falls into the position change guide hole Tab, and changes to the target position (the leg 10a faces downward and the head 10b faces upward) (see FIGS. 10C and 10D). As the article take-out system 1 further tilts the storage groove T vertically, the article 10 moves from the position change guide hole Tab to the fitting groove Tb in the target position (see FIG. 10E).

[0084] Fig. 11 is a flowchart showing an example of processing performed by the control unit 60 when operating the robot hand 40 according to the second embodiment. The flowchart in Fig. 11 differs from the flowchart in Fig. 7 only in that processing of step S3a is added between steps S3 and S4, and processing of step S4a is added between steps S4 and S5.

[0085] That is, in step S3, the control unit 60 according to this embodiment first performs a process (step S3a) of changing the article holding unit 42 to a horizontal state so that the article 10 can be received from the pickup unit 41 after having the pickup unit 41 pick up the article 10. Then, in step S4, the control unit 60 performs a process (step S4a) of gradually changing the article holding unit 42 from a horizontal state to a vertical state while the article 10 is rolling in the guide groove Ta after having the pickup unit 41 release the article 10. As a result, the article 10 that has landed in the guide groove Ta moves to the fitting groove Tb of the storage groove T, as described with reference to Figs. 8 and 10.

[0086] As described above, the article take-out system 1 according to this embodiment is configured to regulate and promote the movement of the article 10 in the storage groove T by controlling the inclination angle of the storage groove T. This makes it possible to efficiently regulate the rolling behavior of the article 10 in the storage groove T and smoothly control the posture of the article 10.

[0087] (Third embodiment) Next, the configuration of an article pick-up system 1 according to a third embodiment will be described with reference to FIGS.

[0088] Fig. 12 is a diagram showing an example of the configuration of the robot hand 40 according to the third embodiment. Fig. 12A to Fig. 12D show the operation of the robot hand 40 according to the third embodiment in time series.

[0089] Fig. 13 is a diagram showing an example of a manner in which the article 10 rolls in the storage groove T formed by the article holding unit 42 of the robot hand 40 according to the third embodiment. Fig. 13A to Fig. 13E show an example of a manner in which the article 10 rolls in time series from when the article 10 is dropped from the pickup unit 41 into the storage groove T of the article holding unit 42 until when the article 10 is fitted into the fitting groove Tb.

[0090] The article taking system 1 according to this embodiment differs from the article taking system 1 according to the second embodiment in that it utilizes centrifugal force acting on the article 10 to regulate and promote the movement of the article 10 that has fallen into the storage groove T. In other words, in the article taking system 1 according to this embodiment, the external force acting on the article 10 that has fallen into the storage groove T is controlled by centrifugal force. Note that in the article taking system 1 according to this embodiment, the configuration of the article holding unit 42 (i.e., the shape of the storage groove T) is the same as that of the article holding unit 42 according to the second embodiment. Note that the centrifugal force acting on the article 10 can be controlled by the robot arm 30 rotating the robot hand 40.

[0091] The operation of the article pick-up system 1 according to this embodiment is, for example, as follows.

[0092] First, the article pickup system 1 first performs a picking operation of the article 10 by the pickup unit 41. In this stage, the article pickup system 1 holds the pair of gripping members 42A, 42B in a state where they are lifted above the lower end of the pickup unit 41 (i.e., in an open state) so that the lower end of the pickup unit 41 protrudes downward (see FIG. 12A).

[0093] Next, the article taking out system 1 controls the pair of gripping members 42A, 42B to operate in the "closed side", and the opposing surfaces of the left gripping member 42A and the right gripping member 42B are butted together to form a storage groove T for receiving the article 10 directly below the pickup unit 41. Then, the article taking out system 1 causes the pickup unit 41 to release the holding state of the article 10, and causes the article 10 dropped from the pickup unit 41 to be received in the storage groove T formed by the article holding unit 42 (see FIG. 12B). In this embodiment, the state of the storage groove T when receiving the article 10 dropped from the pickup unit 41 is referred to as the "horizontal state".

[0094] Next, the article pickup system 1 rotates the article holder 42 in a horizontal plane using the robot arm 30 while the storage groove T is facing horizontally (FIG. 12C). As a result, the article 10 rolls along the groove shape of the storage groove T due to an external force (here, centrifugal force) acting on the article 10 without contact, changes to a target posture, and is positioned at a predetermined position (the fitting groove Tb shown in FIG. 9) in the storage groove T (see FIG. 12D).

[0095] Next, the article pickup system 1 further operates the pair of gripping members 42A, 42B to the "closing side" to grip the article 10 positioned in the storage groove T (not shown).

[0096] The article 10 rolls in the storage groove T in the article pickup system 1 according to this embodiment as follows.

[0097] In the article pickup system 1 according to this embodiment, the article 10 first lands on the guide groove Ta from the pickup unit 41 (see FIG. 13A), and rolls along the groove shape of the guide groove Ta toward the posture change guide hole Tab (see FIG. 13B). Then, the article 10 falls into the posture change guide hole Tab of the guide groove Ta by the action of gravity, utilizing the effect of promoting movement due to centrifugal force (see FIG. 13C). Then, the article 10 that has fallen into the posture change guide hole Tab changes to a target posture (a posture in which the legs 10a face down and the head 10b faces up) (see FIG. 13D), and moves in that posture to the fitting groove Tb due to the influence of centrifugal force (see FIG. 13E).

[0098] Fig. 14 is a flowchart showing an example of processing performed by the control unit 60 when operating the robot hand 40 according to the third embodiment. The flowchart in Fig. 14 differs from the flowchart in Fig. 11 only in that processing in step S4b is added between steps S4 and S5 instead of processing in step S4a.

[0099] That is, the control unit 60 according to this embodiment is configured to perform a process (step S4b) of applying centrifugal force to the article holding unit 42 after releasing the article 10 from the pickup unit 41 in step S4. As a result, the article 10 that has landed in the guide groove Ta moves to the fitting groove Tb of the storage groove T, as described with reference to Figs. 12 and 13.

[0100] As described above, the article taking out system 1 according to this embodiment is configured to regulate and promote the movement of the article 10 in the storage groove T by controlling the centrifugal force acting on the article holding portion 42. This makes it possible to efficiently regulate the rolling behavior of the article 10 in the storage groove T and smoothly control the posture of the article 10.

[0101] (Fourth embodiment) Next, the configuration of an article pick-up system 1 according to a fourth embodiment will be described with reference to FIGS.

[0102] FIG. 15 is a diagram showing an example of the configuration of a robot hand 40 according to the fourth embodiment.

[0103] Fig. 16 is a diagram showing an example of a manner in which an article 10 rolls in a storage groove T formed by an article holding unit 42 of a robot hand 40 according to the fourth embodiment. Fig. 16A to Fig. 16C show an example of a manner in which the article 10 rolls in time series from when the article 10 is dropped from the pickup unit 41 into the storage groove T of the article holding unit 42 until when the article 10 is fitted into a fitting groove Tb.

[0104] The article taking system 1 according to this embodiment differs from the article taking system 1 according to the third embodiment in that the article taking system 1 according to this embodiment utilizes an inertial force acting on the article 10 to regulate and promote the movement of the article 10 that has dropped into the storage groove T. In other words, in the article taking system 1 according to this embodiment, the external force acting on the article 10 that has dropped into the storage groove T is controlled by an inertial force, thereby regulating and promoting the movement of the article 10 within the storage groove T.

[0105] The inertial force acting on the article 10 can be controlled by accelerating the robot hand 40 with the robot arm 30. In the article pickup system 1 according to the present embodiment, for example, the article 10 can be rolled from the guide groove Ta toward the fitting groove Tb by accelerating the translational movement of the robot hand 40 in the direction opposite to the direction in which the guide groove Ta faces the fitting groove Tb.

[0106] As shown in Figures 15 and 16, the item taking out system 1 of this embodiment has the same configuration and operation as the item taking out system 1 of the third embodiment, except that the external force acting on the item 10 dropped into the storage groove T is controlled by inertial force instead of centrifugal force.

[0107] As described above, the article picking system 1 according to this embodiment is configured to regulate and promote the movement of the article 10 in the storage groove T by controlling the inertial force acting on the article 10. This makes it possible to efficiently regulate the rolling behavior of the article 10 in the storage groove T and smoothly control the posture of the article 10.

[0108] Fifth embodiment Next, the configuration of an article pick-up system 1 according to a fifth embodiment will be described with reference to FIGS.

[0109] Fig. 17 is a diagram showing an example of the configuration of a robot hand 40 according to the fifth embodiment. Fig. 17A to Fig. 17B show the operation of the robot hand 40 according to the fifth embodiment in chronological order.

[0110] Fig. 18 is a diagram showing an example of the manner in which the article 10 rolls in the storage groove T formed by the article holding unit 42 of the robot hand 40 according to the fifth embodiment. Fig. 18A to Fig. 18C show an example of the manner in which the article 10 rolls in time series from when the article 10 is dropped from the pickup unit 41 into the storage groove T of the article holding unit 42 until when the article 10 is fitted into the fitting groove Tb.

[0111] The article taking out system 1 according to the present embodiment differs from the article taking out system 1 according to the second embodiment in that it utilizes a magnetic force generated by a magnet MG disposed adjacent to or within the article holding unit 42 to regulate and promote the movement of the article 10 dropped into the storage groove T. In other words, in the article taking out system 1 according to the present embodiment, the external force acting on the article 10 dropped into the storage groove T is controlled by a magnetic force. Note that, in the article taking out system 1 according to the present embodiment, in addition to the external force due to the magnetic force generated by the magnet MG, the inclination angle of the storage groove T with respect to the vertical direction is controlled to regulate and promote the movement of the article 10 in the storage groove T, similar to the article taking out system 1 according to the second embodiment.

[0112] The operation of the article pick-up system 1 according to this embodiment is, for example, as follows.

[0113] First, the article taking out system 1 first performs a picking operation of the article 10 by the pickup unit 41. Then, the article taking out system 1 causes the pickup unit 41 to release the held state of the article 10, and causes the article 10 that falls from the pickup unit 41 to be received in the storage groove T of the article holding unit 42 (see Figs. 17A and 18A). Note that in the article taking out system 1 according to this embodiment, the article holding unit 42 is configured by a container-shaped member having the storage groove T. When the article 10 fits into the fitting groove Tb, the article holding unit 42 according to this embodiment grips the article 10 by covering the article 10 from above the container-shaped member with a separate gripping member 42C.

[0114] Next, while the article 10 is rolling in the storage groove T, the article take-out system 1 applies a magnetic force from the magnet MG to the article 10 to guide the article 10 to a predetermined position (here, a position facing the fitting groove Tb) and changes the posture of the article 10 to the target posture (see FIG. 18B). After the article 10 has changed to the target posture, the article take-out system 1 retracts the magnet MG from the article holding unit 42 and releases the magnetic force from the magnet MG. The article take-out system 1 then changes the article holding unit 42 to a vertical state. As a result, the article 10, having been changed to the target posture, fits into the fitting groove Tb in the storage groove T and is positioned within the fitting groove Tb (see FIGS. 17B and 18C).

[0115] Fig. 19 is a flowchart showing an example of processing performed by the control unit 60 when operating the robot hand 40 according to the fifth embodiment. The flowchart in Fig. 19 differs from the flowchart in Fig. 11 in that a process of step S4c is added immediately after the process of step S4, and in that a process of step S4d is added instead of the process of step S4a. In addition, in the article pickup system 1 according to this embodiment, the article holding unit 42 is configured by a container-shaped member having a storage groove T, and therefore the process of step S3 in the flowchart in Fig. 11 is omitted in the flowchart in Fig. 19.

[0116] That is, in step S4, after the control unit 60 according to this embodiment causes the pickup unit 41 to release the article 10, while the article 10 is rolling in the storage groove T, the control unit 60 attracts the article 10 with the magnet MG and changes the posture of the article 10 to the target posture (step S4c). The control unit 60 is then configured to perform a process (step S4d) of moving the magnet MG away from the article holding unit 42 and changing the article holding unit 42 to a vertical state. As a result, as described with reference to Figs. 17 and 18, the article 10 that has landed in the storage groove T moves to the fitting groove Tb.

[0117] The magnet MG may be a permanent magnet or an electromagnet. When the magnet MG is an electromagnet, the control unit 60 may variably control the magnetic force of the magnet MG to change the external force acting on the article 10.

[0118] As described above, the article picking system 1 according to this embodiment is configured to restrict and promote the movement of the article 10 in the storage groove T by controlling the magnetic force applied to the article 10 by the magnet MG. This makes it possible to accurately control the posture of the article 10 rolling in the storage groove T.

[0119] Sixth embodiment Next, the configuration of an article pick-up system 1 according to a sixth embodiment will be described with reference to FIGS.

[0120] 20 and 21 are diagrams showing an example of the configuration of a robot hand 40 according to the sixth embodiment.

[0121] The article taking out system 1 according to this embodiment differs from the article taking out system 1 according to the second embodiment in that the article taking out system 1 according to this embodiment utilizes fluid pressure generated by an air pump MF disposed adjacent to or within the article holding unit 42 in order to regulate and promote the movement of the article 10 dropped into the storage groove T. In other words, in the article taking out system 1 according to this embodiment, the external force acting on the article 10 dropped into the storage groove T is controlled by fluid pressure.

[0122] This makes it possible to accurately control the posture of the article 10 rolling within the storage groove T.

[0123] Seventh embodiment Next, the configuration of an article pick-up system 1 according to a seventh embodiment will be described with reference to FIGS.

[0124] 22 and 23 are diagrams for explaining the operation of the robot hand 40 according to the seventh embodiment.

[0125] The article pick-up system 1 according to the seventh embodiment differs from the article pick-up systems 1 according to the above embodiments in that the article pick-up system 1 according to the seventh embodiment can accommodate articles 10 of various sizes by variably controlling the distance between the members of the article holding section 42.

[0126] Depending on the manufacturing site of the product, there may be cases where the group of articles 10W placed on the article placement unit 2 includes articles 10 of different sizes, such as the articles 10s and 10t in FIG. 22. The articles 10s and 10t shown in FIG. 22 are the same type of articles 10 (e.g., bolt members) with different heights and widths (here, the article 10s has a height Hs and a width Ws, and the article 10t has a height Ht and a width Wt). In the article take-out system 1 according to the present embodiment, in order to be able to handle such a situation, the inter-member distance of the article holding unit 42 is changed according to the size of the article 10 to be taken out (see FIG. 23A and FIG. 23B). In the article take-out system 1 according to the present embodiment, the hole size of the posture change guide hole Tab of the storage groove T and the groove size of the fitting groove Tb are thereby changed, and it is possible to change the posture of the articles 10 of different sizes to the target posture and to hold the articles 10 in the target posture.

[0127] The article pick-up system 1 according to the present embodiment may be configured to determine the inter-member distance of the article holding unit 42 according to the size of the article 10 specified by the user, but more preferably, when an article 10 to be picked is determined from the group of articles 10W placed on the article placement unit 2, the size of the article 10 is detected from image data obtained from the imaging unit 50, and the inter-member distance of the article holding unit 42 is adjusted based on the detected size of the article 10. This makes it possible to accurately change the posture of the article 10 to the target posture even when the group of articles 10W placed on the article placement unit 2 contains a mixture of articles 10 of different sizes.

[0128] As described above, the article pick-up system 1 according to this embodiment can be applied to articles 10 of different sizes with the same configuration.

[0129] (Other embodiments) The present invention is not limited to the above-described embodiment, and various modifications are possible. For example, the article pick-up system 1 may have a configuration in which the aspects shown in the respective embodiments are combined in various ways.

[0130] In addition, in the above embodiment, a bolt member is shown as an example of the article 10, but the article 10 may be any article other than a bolt member, and may be, for example, an L-shaped fastener, a cap, a cylindrical member attached to a part of a rod-shaped member, a cap, etc. However, from the viewpoint of changing the position by rolling in the guide groove Ta, the article 10 is preferably a member having a shape having a long and slender leg 10a and a head 10b formed at one end of the leg 10a and wider than the leg 10a.

[0131] In addition, in the above embodiment, a suction head is shown as an example of the configuration of the pickup unit 41, but the pickup unit 41 may be configured as a two-jaw hand that holds the article 10 by clamping the article 10 from the side. However, it is preferable that the pickup unit 41 is configured as a suction head, since the pickup unit 41 can pick up the article 10 placed in various positions without being affected by the differences in position.

[0132] Furthermore, in the above embodiment, one example of the configuration of the article holding part 42 has been shown, but the configuration of the article holding part 42 can be modified in various ways. For example, the article holding part 42 may be configured by combining a member forming a guide groove Ta that changes the posture of the article 10 to a target posture and a member forming a fitting groove Tb (i.e., a member that grips the article 10). Furthermore, instead of the article holding part 42 in which the storage groove T is formed by a pair of gripping members 42A, 42B, the article holding part 42 may be configured with a container-shaped article holding part 42 in which the storage groove T is formed in advance.

[0133] Although the specific examples of the present invention have been described in detail above, these are merely examples and do not limit the scope of the claims. The technology described in the claims includes various modifications and changes of the specific examples exemplified above. [Industrial Applicability]

[0134] According to the robot hand of the present disclosure, with a simple configuration, it is possible to hold an article taken out from an article placement section after changing its posture to a target posture. [Explanation of symbols]

[0135] 1. Item retrieval system 2. Item placement section 10 Goods 10W article group 20 Installation Target 21 Hole 30 Robot Arm 40 Robot Hand 40T Hand base 41 Pickup section 42 Article holding part 42A, 42B gripping member 42C Gripping member 42x Posture change unit 42y grip part 43 Sensor section 50 Imaging unit 60 Control section MF Air Pump MG Magnet T-shaped groove Ta Guide groove Taa slope Tab Posture change guide hole Tb fitting groove Tbb through hole

Claims

1. a pickup unit that picks up an individual article from a group of articles placed on the article placement unit and holds the article; an article holding section that receives the article released by the pickup section; The article holding portion is a posture changing unit that changes the posture of the article to a target posture by rolling the article released from the pickup unit and regulating the rolling manner of the article; a gripping unit that grips the article whose posture has been changed to the target posture, Robot hand for item picking system.

2. the position change unit is formed in a receiving area in a storage groove formed directly below the pickup unit where the article released from the pickup unit lands, and includes a guide groove that changes the position of the article to the target position while rolling the article; The gripping portion is formed in a region guided by the guide groove in the storage groove, and includes a fitting groove for positioning the article changed to the target posture. The robot hand according to claim 1 .

3. The article has an elongated leg and a head formed at one end of the leg and wider than the leg; The guide groove includes a posture change guide hole that does not allow the head of the article to pass through and allows the leg of the article to pass through in a path that guides the article from the receiving area to the fitting groove, and changes the posture of the article to the target posture in the process of the article passing through the posture change guide hole. The robot hand according to claim 2.

4. A sensor unit for detecting whether the article is fitted in the fitting groove is provided. The robot hand according to claim 2 or 3.

5. The article holding portion holds the article such that a portion of the article protrudes from a storage groove formed by the article holding portion directly below the pickup portion. The robot hand according to any one of claims 1 to 4.

6. The force that rolls the article in the posture changing section includes gravity. The robot hand according to any one of claims 1 to 5.

7. The force that rolls the article in the posture changing section includes a magnetic force generated by a magnet disposed adjacent to or within the article holding section. The robot hand according to any one of claims 1 to 6.

8. The force that rolls the article in the posture changing section includes a centrifugal force generated by the rotational motion of the article holding section. The robot hand according to any one of claims 1 to 7.

9. The force that rolls the article in the posture changing section includes an inertial force generated by the accelerated motion of the article holding section. The robot hand according to any one of claims 1 to 8.

10. The force that rolls the article in the position changing section includes a fluid pressure generated by an air pump disposed adjacent to or within the article holding section. The robot hand according to any one of claims 1 to 9.

11. The article holding section is composed of a pair of gripping members arranged opposite to each other and abutting their respective opposing surfaces to form a storage groove directly below the pickup section, The distance between the pair of gripping members can be controlled by a control unit that controls the article pick-up system. The robot hand according to any one of claims 1 to 10.

12. By adjusting the inter-member distance between the pair of gripping members, a gripping state and a non-gripping state of the article in the article holding portion are changed. The robot hand according to claim 11.

13. The movement of the article in the storage groove is restricted by adjusting the distance between the pair of gripping members. The robot hand according to claim 11 or 12.

14. The distance between the pair of gripping members is adjusted based on the size of the article. The robot hand according to any one of claims 11 to 13.

15. The inclination angle of the storage groove formed by the article holding unit directly below the pickup unit with respect to the vertical direction can be controlled by a control unit that controls the article pick-up system. The robot hand according to any one of claims 1 to 14.

16. The inclination angle of the storage groove is adjusted to restrict movement of the article within the storage groove. The robot hand according to claim 15.

17. By adjusting the inclination angle of the storage groove, the article is caused to perform a retry of the rolling motion in the storage groove. The robot hand according to claim 15 or 16.

18. The article holding unit is configured to be capable of vibrating, and the vibrating motion promotes movement of the article within a storage groove that the article holding unit forms directly below the pickup unit. A robot hand according to any one of claims 1 to 17.

19. The pickup unit is constituted by a suction head. A robot hand according to any one of claims 1 to 18.

20. An article pick-up system comprising the robot hand according to any one of claims 1 to 19.

Images