Robot system

Abstract

This robot system (100) is provided with a container (20) that comprises a workpiece storage space (S) surrounded by: a pair of first inclined surfaces (21) having a lower-end side (21a) that touches a straight line (A) extending along a predetermined direction (X); and a pair of second inclined surfaces (22) each having a pair of sides (22a) connected to an end of the lower-end side (21a) of the pair of first inclined surfaces (21).

Description

Robot System

[0001] This disclosure relates to robotic systems.

[0002] Conventionally, robot systems equipped with a hand for holding workpieces placed in a container have been disclosed. Japanese Patent Application Laid-Open Publication No. 2017-201276 discloses a robot system for holding bulk-stacked workpieces. This robot system includes a chuck-type hand for holding the workpieces and a robot arm to which the hand is attached. In Japanese Patent Application Laid-Open Publication No. 2017-201276, the workpieces are placed in a container. The bottom surface of the container includes a square bottom surface along the horizontal direction and four inclined surfaces connected to each side of the square bottom surface and intersecting the bottom surface. As a result, since the container includes the inclined surfaces, the bulk-stacked workpieces are gathered in the center of the bottom surface of the container. This makes it possible for the hand to hold the workpieces gathered in the center of the bottom surface without the robot arm moving significantly.

[0003] Japanese Patent Application Laid-Open No. 2017-201276

[0004] The bottom surface of the container disclosed in JP 2017-201276 A includes a horizontally oriented square bottom surface and four inclined surfaces connected to each side of the square bottom surface and intersecting the bottom surface. In this case, the workpiece may stop near the boundary between the horizontally oriented bottom surface and the inclined surfaces, and may not move to the horizontally oriented bottom surface. Furthermore, because the bottom surface is horizontally oriented, it is not possible to determine at which position on the horizontally oriented bottom surface the workpiece will stop. This variation in the position of the workpiece poses a problem in that the robot arm must move relatively far to hold the workpiece in the hand.

[0005] This disclosure has been made to solve the above-mentioned problems, and one objective of this disclosure is to provide a robot system that can hold a workpiece placed in a container without moving the robot arm significantly.

[0006] A robot system according to one aspect of this disclosure includes a robot arm, a hand attached to the robot arm and configured to hold a workpiece, a container including a workpiece storage space surrounded by a pair of first inclined surfaces whose lower edge portions meet on a line extending in a predetermined direction when viewed from above, and a pair of second inclined surfaces each having a pair of edges connected to the ends of the lower edge portions of the pair of first inclined surfaces, and a control unit that executes control to cause the hand to hold a workpiece placed in the workpiece storage space of the container.

[0007] In one aspect of the present disclosure, the robot system includes a container including a workpiece storage space surrounded by a pair of first inclined surfaces whose lower edges meet on a line extending in a predetermined direction when viewed from above, and a pair of second inclined surfaces, each of which has a pair of edges connected to the ends of the lower edges of the pair of first inclined surfaces. This gives the workpiece storage space a shape with a pointed tip due to the pair of first inclined surfaces whose lower edges meet. Therefore, unlike a container having a bottom surface aligned horizontally, the workpiece moves along the first inclined surfaces or the second inclined surfaces to a relatively fixed position where the lower edges of the pair of first inclined surfaces meet. This allows the robot arm to hold the workpiece placed in the container without moving the robot arm significantly.

[0008] The robot system of the present disclosure can hold a workpiece placed in a container without moving the robot arm significantly.

[0009] 1 is a diagram showing a robot system according to an embodiment; FIG. 1 is a diagram showing a container according to an embodiment as viewed from above; FIG. 2 is a cross-sectional view taken along line 200-200 of the container shown in FIG. 2; FIG. 3 is a diagram showing a container with a marker placed thereon according to an embodiment; FIG. 4 is a diagram showing a robot according to an embodiment; FIG. 5 is a diagram showing a state in which a chuck according to an embodiment is fully open; FIG. 6 is a control block diagram of a robot system according to an embodiment; FIG. 7 is a diagram showing a workpiece placed at a position where the lower edges of a pair of first inclined surfaces are in contact with each other; FIG. 8 is a diagram showing a marker imaged by an imaging unit showing a state in which no workpiece is placed; FIG. 9 is a diagram showing a marker imaged by an imaging unit showing a state in which a workpiece is placed; FIG. 10 is a diagram showing a state before workpieces are replenished by a robot arm; FIG. 11 is a diagram showing a state after workpieces have been replenished by a robot arm; FIG. 12 is a diagram showing a state in which workpieces are stopped on the first inclined surface side of the container; FIG. 13 is a diagram showing a state in which workpieces are stopped at the boundary between the first inclined surface and the second inclined surface of the container; FIG. 14 is a diagram showing a container according to a modified example as viewed from above; FIG. 15 is a diagram for explaining a method of supplying workpieces according to a modified example;

[0010] An embodiment of the present disclosure that embodies the present disclosure will be described below with reference to the drawings. In this specification, the up-down direction is referred to as the Z direction. The upper side is referred to as the Z1 side, and the lower side is referred to as the Z2 side. The direction perpendicular to the Z direction is referred to as the X direction. One side of the X direction is referred to as the X1 side, and the other side is referred to as the X2 side. The direction perpendicular to the Z direction and the X direction is referred to as the Y direction. One side of the Y direction is referred to as the Y1 side, and the other side is referred to as the Y2 side. The X direction is an example of a predetermined direction.

[0011] The configuration of a robot system 100 will be described. As shown in Fig. 1, the robot system 100 includes a robot 10 and a container 20. The robot system 100 performs an operation of holding a workpiece 1 placed in the container 20 and transferring it to another container 30. The workpiece 1 is, for example, a fastening member such as a bolt. A container supply unit 40 is also disposed near the robot 10 and the container 20.

[0012] (Container) The configuration of the container 20 will be described. As shown in FIG. 2 , in this embodiment, the container 20 includes a pair of first inclined surfaces 21 and a pair of second inclined surfaces 22. The pair of first inclined surfaces 21 have a trapezoidal shape. The pair of second inclined surfaces 22 have a triangular shape. When viewed from above, the lower edge 21 a of each of the pair of first inclined surfaces 21 is tangent to a line A extending along the X direction. As shown in FIG. 1 , when the sides of the box-shaped container 20 are arranged so that they extend along the X direction, the direction in which the line A extends is the X direction, but the direction in which the line A extends changes depending on the orientation of the container 20. The first inclined surface 21 also includes an upper edge 21 b opposite the lower edge 21 a and a side edge 21 c connecting the lower edge 21 a and the upper edge 21 b. Each of the pair of second inclined surfaces 22 has a pair of sides 22a connected to the ends of the lower edges 21a of the pair of first inclined surfaces 21. The ends of the lower edges 21a of the first inclined surfaces 21 refer to the ends of the lower edges 21a on the X1 and X2 sides. The second inclined surfaces 22 also include upper edges 22b connected to the pair of sides 22a. As shown in FIG. 3 , the container 20 includes a workpiece storage space S surrounded by the pair of first inclined surfaces 21 and the pair of second inclined surfaces 22. The workpiece storage space S has a shape recessed toward the Z2 direction. The pair of first inclined surfaces 21 have the same shape. The pair of second inclined surfaces 22 have the same shape. In FIG. 2 , the lower edges 21a of the first inclined surfaces 21 and the edges 22a of the second inclined surfaces 22 are indicated by the same line. A mark 24, which will be described later, is omitted from FIG. 2 and other figures.

[0013] 1, the container 20 includes a box-shaped main body 23 on which the pair of first inclined surfaces 21 and the pair of second inclined surfaces 22 are arranged. The pair of first inclined surfaces 21 and the pair of second inclined surfaces 22 may be formed integrally with the main body 23 or may be formed separately.

[0014] 4, the container 20 includes a marker 24 disposed across the pair of first inclined surfaces 21 and the pair of second inclined surfaces 22. Specifically, the marker 24 is disposed across the lower edge 21a of each of the pair of first inclined surfaces 21 and the Z2-side portion of each of the pair of edges 22a of each of the pair of second inclined surfaces 22. The marker 24 has a rectangular shape when viewed from the Z1 direction.

[0015] In this embodiment, the mark 24 includes paint applied to the container 20. For example, the paint is paint or the like. The color of the mark 24 is different from the colors of the pair of first inclined surfaces 21 and the pair of second inclined surfaces 22. For example, the color of the mark 24 is green, and the color of the pair of first inclined surfaces 21 and the pair of second inclined surfaces 22 is white. In FIG. 4, the color of the mark 24 is represented by hatching.

[0016] (Robot) The configuration of the robot 10 will be described. As shown in FIG. 5 , the robot 10 includes a robot arm 11, a hand 12, an imaging unit 13, a cart unit 14, a moving unit 15, and a control unit 16. The robot arm 11 is a vertically articulated robot arm having multiple joints. For example, the robot arm 11 is a six-axis vertically articulated arm. The robot arm 11 has a driving unit 11a shown in FIG. 7 that serves as a driving source for each of the multiple joints. The driving source of the robot arm 11 includes, for example, a servo motor.

[0017] The hand 12 is an end effector disposed at the tip of the robot arm 11. The hand 12 holds the workpiece 1. In this embodiment, the hand 12 includes a chuck 12a. When a pair of claws of the chuck 12a are arranged along the X direction, the chuck 12a opens and closes along the X direction. As shown in FIG. 6 , the length L2 of the opening and closing range of the chuck 12a along the X direction is equal to or greater than the length L1 of the lower edge 21a of the first inclined surface 21 of the container 20 shown in FIG. 2 . The length L2 of the opening and closing range of the chuck 12a along the X direction is the length between the pair of claws. The hand 12 also includes a drive unit 12b shown in FIG. 7 that opens and closes the chuck 12a. The drive unit 12b includes a servo motor, an encoder, and a reducer.

[0018] 5 , in this embodiment, the imaging unit 13 captures two-dimensional images of the workpiece 1 and the marker 24 placed in the container 20. The imaging unit 13 includes an image sensor such as a charge coupled device (CCD) or a complementary metal oxide semiconductor (CMOS). The imaging unit 13 is disposed in the hand 12, for example. The two-dimensional image captured by the imaging unit 13 is transmitted to the control unit 16.

[0019] The cart unit 14 is a box-shaped housing. The moving unit 15 moves the cart unit 14. The moving unit 15 has a plurality of wheels that rotate while supporting the cart unit 14, and a servo motor that drives the plurality of wheels. In addition, the robot arm 11 is disposed on the upper surface of the cart unit 14. The control unit 16 executes a process of moving the robot arm 11 by the moving unit 15 to the vicinity of the container 20. For example, the control unit 16 executes a process of moving the robot arm 11 by the moving unit 15 to the vicinity of the workbench 50 shown in FIG. 11 on which the container 20 is placed.

[0020] The configuration of the control unit 16 will be described. The control unit 16 is a robot controller. As shown in FIG. 7 , the control unit 16 includes a main control unit 16a, a servo control unit 16b, a drive circuit unit 16c, and a storage unit 16d. The main control unit 16a and the servo control unit 16b each include, for example, a central processing unit (CPU). The main control unit 16a controls the drive unit 11a of the robot arm 11 and the drive unit 12b of the hand 12. The servo control unit 16b controls the power supplied to the drive unit 11a of the robot arm 11 and the drive unit 12b of the hand 12 based on commands from the main control unit 16a. The drive circuit unit 16c supplies drive power to the drive unit 11a of the robot arm 11 and the drive unit 12b of the hand 12. The drive circuit unit 16c is provided for each of the drive units 11a of the robot arm 11. Each of the driving units 11a includes a servo motor, an encoder, and a reducer. The storage unit 16d stores programs executed by the control unit 16 and the like.

[0021] In this embodiment, the control unit 16 executes control to cause the hand 12 to hold the workpiece 1 placed in the workpiece storage space S of the container 20. Specifically, as shown in FIG. 8 , the control unit 16 executes a process to cause the chuck 12a to hold the workpiece 1 placed at position P where the lower edge 21a of the pair of first inclined surfaces 21 contact each other. That is, the control unit 16 does not detect the position or shape of the workpiece 1 using a 3D camera or the like, but is instructed in advance to hold the workpiece 1 at position P where the lower edge 21a of the pair of first inclined surfaces 21 contact each other. That is, the control unit 16 executes control to repeatedly hold the workpiece 1 placed at position P where the lower edge 21a of the pair of first inclined surfaces 21 contact each other and transfer the held workpiece 1 to another container 30. The position P where the lower edges 21 a of the pair of first inclined surfaces 21 meet is a line segment where the lower edge 21 a of the first inclined surface 21 located on the Y1 side and the lower edge 21 a of the first inclined surface 21 located on the Y2 side meet when viewed from above. Furthermore, since the length L2 of the opening and closing range of the chuck 12 a is equal to or greater than the length L1 of the lower edge 21 a of the first inclined surface 21 of the container 20, the workpiece 1 can be held by the chuck 12 a regardless of the position of the line segment at position P where the workpiece 1 is located. Furthermore, since the container 20 includes the first inclined surface 21 and the second inclined surface 22, when one workpiece 1 is moved from the container 20 to the container 30, another workpiece 1 moves to position P. This allows multiple workpieces 1 to be held and moved continuously at position P.

[0022] In this embodiment, the control unit 16 determines whether the workpiece 1 is placed on the marker 24 based on a two-dimensional image of the workpiece 1 and the marker 24 placed in the container 20 captured by the imaging unit 13. Specifically, as shown in FIG. 9 , the shape of the image of the marker 24 when the workpiece 1 is not placed on the marker 24 is pre-stored in the memory unit 16d. The control unit 16 extracts the shape of the marker 24 from the image captured by the imaging unit 13. If the shape of the extracted marker 24 does not match the shape of the image of the marker 24 stored in the memory unit 16d, the control unit 16 determines that the workpiece 1 is placed on the marker 24. For example, as shown in FIG. 10 , if the workpiece 1 is placed on the marker 24, the shape of the extracted marker 24 is such that the shape of the workpiece 1 is cut out. If the shape of the extracted marker 24 matches the shape of the image of the marker 24 stored in the memory unit 16d, the control unit 16 determines that the workpiece 1 is not placed on the marker 24. That is, the control unit 16 determines that no workpiece 1 remains in the container 20.

[0023] In this embodiment, when the control unit 16 determines that no workpiece 1 is placed on the marker 24, it causes the robot arm 11 to execute an operation to replenish the workpiece 1. Specifically, as shown in FIG. 11 , a container supply unit 40 is disposed near the robot arm 11. A roller 41 is disposed in the container supply unit 40, and the container 20 is disposed on the roller 41. The container supply unit 40 is rotatable around a rotation axis B. A weight 42 is also attached to the container supply unit 40. When the control unit 16 determines that no workpiece 1 is placed on the marker 24, it causes the empty container 20 to move to a predetermined location. Note that the movement unit 15 may also move the robot 10 to move the container 20 to a predetermined location. Then, as shown in FIG. 12 , the control unit 16 tilts the container supply unit 40 using the robot arm 11 and the hand 12. For example, the hand 12 presses the container supply unit 40 downward. As a result, the container 20 slides on the rollers 41 and is moved to the upper surface of the work table 50. When the hand 12 is released from pressing down on the container supply unit 40, the weight of the weight 42 causes the container supply unit 40 to return to a horizontal position. Another container 20 containing a workpiece 1 is replenished in the container supply unit 40 that has returned to a horizontal position.

[0024] In this embodiment, when the control unit 16 determines, based on the image captured by the imaging unit 13, that the workpiece 1 is positioned at a position displaced from the position P where the lower edges 21 a of the pair of first inclined surfaces 21 contact each other, the control unit 16 executes a process of moving the workpiece 1 by the chuck 12 a to the position P where the lower edges 21 a of the pair of first inclined surfaces 21 contact each other. For example, as shown in FIG. 13 , the workpiece 1 may be stopped at a position displaced toward the Y1 side from the position P. The control unit 16 determines that the workpiece 1 is displaced from the position P by image processing or the like from the image captured by the imaging unit 13. Then, the control unit 16 executes a process of moving the robot arm 11 and moving the workpiece 1 to the position P by the chuck 12 a. For example, the control unit 16 slides the workpiece 1 to the position P by the chuck 12 a.

[0025] In this embodiment, when the control unit 16 determines, based on the image captured by the imaging unit 13, that the workpiece 1 is positioned at a position where the pair of first inclined surfaces 21 and second inclined surfaces 22 contact each other, the control unit 16 executes a process of moving the workpiece 1 by the chuck 12a to position P where the lower edges 21a of the pair of first inclined surfaces 21 contact each other. For example, as shown in FIG. 14 , the workpiece 1 may be stopped at a position where the lateral edge 21c of the first inclined surface 21 contacts the edge 22a of the second inclined surface 22. The control unit 16 determines, based on the image captured by the imaging unit 13, by image processing or the like, that the workpiece 1 has shifted from position P. The control unit 16 then executes a process of moving the robot arm 11 and moving the workpiece 1 to position P by the chuck 12a. For example, by bringing the chuck 12a into contact with the workpiece 1, the workpiece 1 falls to position P due to its own weight.

[0026] [Effects of this embodiment] When viewed from above, the container 20 includes a workpiece storage space S surrounded by a pair of first inclined surfaces 21 whose lower edge 21 a contacts a straight line A extending along the X direction, and a pair of second inclined surfaces 22, each of which has a pair of edges 22 a connected to the ends of the lower edge 21 a of the pair of first inclined surfaces 21. As a result, the workpiece storage space S has a shape with a pointed tip downward due to the pair of first inclined surfaces 21 whose lower edge 21 a contacts each other, so the workpiece 1 moves along the first inclined surfaces 21 or the second inclined surfaces 22 to a relatively fixed position P where the lower edge 21 a of the pair of first inclined surfaces 21 contact each other. This makes it possible to hold the workpiece 1 placed in the container 20 without moving the robot arm 11 significantly.

[0027] The pair of first inclined surfaces 21 have a trapezoidal shape, and the pair of second inclined surfaces 22 have a triangular shape. As a result, the workpiece storage space S can be easily formed by connecting the lateral sides 21 c connecting the lower edge 21 a and the upper edge 21 b of each of the pair of trapezoidal first inclined surfaces 21 with the second inclined surfaces 22.

[0028] The hand 12 includes a chuck 12a that opens and closes along the X direction, and the length L2 of the opening and closing range of the chuck 12a along the X direction is equal to or greater than the length L1 of the lower edge 21a of the first inclined surface 21. This allows the workpiece 1 to be held by the chuck 12a no matter where the workpiece 1 is located on the lower edge 21a of the first inclined surface 21.

[0029] The control unit 16 executes a process of holding the workpiece 1, which is placed at a position P where the lower edges 21a of the pair of first inclined surfaces 21 contact each other, by the chuck 12a. As a result, the position where the workpiece 1 is held by the chuck 12a is fixed, and therefore the control burden on the control unit 16 can be reduced, unlike when the position of the workpiece 1 is detected by a 3D camera or the like and the robot arm 11 is moved to hold the workpiece 1 by the chuck 12a.

[0030] The robot system 100 includes an imaging unit 13 that captures a two-dimensional image of the workpiece 1 placed in the container 20. When the control unit 16 determines, based on the image captured by the imaging unit 13, that the workpiece 1 is placed at a position shifted from the position P where the lower edges 21 a of the pair of first inclined surfaces 21 contact each other, the control unit 16 executes a process of moving the workpiece 1 by the chuck 12 a to the position P where the lower edges 21 a of the pair of first inclined surfaces 21 contact each other. This makes it possible to move and hold the workpiece 1 even when the workpiece 1 is placed at a position shifted from the position P.

[0031] The robot system 100 includes an imaging unit 13 that captures a two-dimensional image of the workpiece 1 placed in the container 20. When the control unit 16 determines, based on the image captured by the imaging unit 13, that the workpiece 1 is placed at position P where the pair of first inclined surfaces 21 and second inclined surfaces 22 contact each other, the control unit 16 executes a process of moving the workpiece 1 by the chuck 12a to position P where the lower edges 21a of the pair of first inclined surfaces 21 contact each other. This allows the workpiece 1 to be moved and held even if the workpiece 1 is placed at a position displaced from position P.

[0032] The container 20 includes a marker 24 arranged across a pair of first inclined surfaces 21 and a pair of second inclined surfaces 22. The robot system 100 includes an imaging unit 13 that captures two-dimensional images of the workpiece 1 and the marker 24 arranged in the container 20. The control unit 16 determines whether or not the workpiece 1 is arranged on the marker 24 based on the image captured by the imaging unit 13. This reduces the control burden on the control unit 16, unlike when determining whether or not the workpiece 1 is present based on a 3D image captured by a 3D camera or the like.

[0033] When the control unit 16 determines that the workpiece 1 is not placed on the marker 24, it causes the robot arm 11 to execute an operation to replenish the workpiece 1. As a result, the workpiece 1 is automatically replenished by the robot arm 11, and the burden of the worker in replenishing the workpiece 1 can be reduced.

[0034] The marker 24 includes paint applied to the container 20. The color of the marker 24 is different from the colors of the pair of first inclined surfaces 21 and the pair of second inclined surfaces 22. This prevents the workpiece 1 from getting caught on the marker 24 and being unable to move to the position P where the lower edges 21 a of the pair of first inclined surfaces 21 contact each other, unlike when the marker 24 is attached to the container 20 with tape or the like. Furthermore, because the color of the marker 24 is different from the colors of the pair of first inclined surfaces 21 and the pair of second inclined surfaces 22, the control unit 16 can easily determine whether or not the workpiece 1 is placed on the marker 24 based on the image captured by the imaging unit 13.

[0035] The robot system 100 includes a carriage unit 14 on which the robot arm 11 is placed, and a movement unit 15 that moves the carriage unit 14. The control unit 16 executes a process of moving the robot arm 11 to the vicinity of the container 20 using the movement unit 15. As a result, since the robot arm 11 is not fixed, even if the container 20 is placed in a separate location, the movement unit 15 can move the robot arm 11 to perform an operation of holding the workpiece 1. Furthermore, even if multiple containers 20 are located in separate locations, a single robot arm 11 can perform an operation of holding the workpiece 1.

[0036] [Modifications] The embodiments disclosed herein should be considered to be illustrative and not restrictive in all respects. The scope of the present disclosure is defined by the claims, not by the description of the above-mentioned embodiments, and includes all modifications (modifications) within the meaning and scope of the claims.

[0037] In the above embodiment, an example has been shown in which the robot arm 11 is a six-axis vertically articulated robot arm, but the present disclosure is not limited to this. For example, the robot arm 11 may be a vertically articulated robot arm having a number of axes other than six, or a horizontally articulated robot arm.

[0038] In the above embodiment, an example has been described in which the pair of first inclined surfaces 21 have the same shape and the pair of second inclined surfaces 22 have the same shape, but the present disclosure is not limited to this. For example, as in the container 120 according to a modified example shown in Fig. 15, the pair of first inclined surfaces 121 may have different shapes. This makes it possible to form a container 120 that is relatively long in the Y direction, as shown in Fig. 15.

[0039] In the above embodiment, an example has been described in which the hand 12 has the chuck 12a, but the present disclosure is not limited to this. For example, the hand 12 may be provided with a suction portion other than the chuck 12a.

[0040] In the above embodiment, the control unit 16 executes a process of causing the chuck 12a to hold the workpiece 1 placed at the position P where the lower edges 21a of the pair of first inclined surfaces 21 contact each other, but the present disclosure is not limited to this. For example, the control unit 16 may execute a process of causing the chuck 12a to hold the workpiece 1 placed at a position slightly shifted from the position P where the lower edges 21a contact each other.

[0041] In the above embodiment, the control unit 16 moves the workpiece 1 by the chuck 12a when it determines, based on the image captured by the imaging unit 13, that the workpiece 1 is positioned at a position shifted from the position P where the lower edges 21a of the pair of first inclined surfaces 21 contact each other, and when it determines that the workpiece 1 is positioned at a position where the pair of first inclined surfaces 21 and the second inclined surface 22 contact each other. However, the present disclosure is not limited to this. For example, when the control unit 16 determines as described above, it may execute a process of causing the chuck 12a to operate in a manner that stirs the workpiece 1.

[0042] In the above embodiment, an example has been shown in which it is determined that no workpiece 1 remains in the container 20 by determining whether or not the workpiece 1 is placed on the sign 24 based on a two-dimensional image of the sign 24 captured by the imaging unit 13, but the present disclosure is not limited to this. For example, the control unit 16 may determine that no workpiece 1 remains in the container 20 based on an image of the inside of the container 20 captured by a 3D camera.

[0043] In the above embodiment, when the control unit 16 determines that the workpiece 1 is not placed on the mark 24, the control unit 16 causes the robot arm 11 to execute an operation to replenish the workpiece 1. However, the present disclosure is not limited to this. For example, when the control unit 16 determines that the workpiece 1 is not placed on the mark 24, the control unit 16 may notify the operator that no workpiece 1 remains in the container 20.

[0044] In the above embodiment, when it is determined that the workpiece 1 is not placed on the marker 24, the control unit 16 tilts the container supply unit 40 using the robot arm 11 and the hand 12 to move the container 20 to the upper surface of the work table 50, as shown in Fig. 12 , but the present disclosure is not limited to this. For example, as shown in Fig. 16 , the control unit 16 may tilt the container storage unit 140 in which the workpiece 1 is stored using the robot arm 11 and the hand 12, and supply the workpiece 1 from the container storage unit 140 to the container 20. In this way, it is sufficient to prepare one container 20 that includes an inclined surface.

[0045] In the above embodiment, the mark 24 is paint applied to the container 20, but the present disclosure is not limited to this. For example, the mark 24 may be tape or the like attached to the container 20.

[0046] In the above embodiment, an example has been described in which the robot arm 11 is placed on the cart unit 14, but the present disclosure is not limited to this. For example, the robot arm 11 may be fixed to the floor or a stationary platform.

[0047] The functions of the elements disclosed herein can be performed using circuits or processing circuits, including general-purpose processors, special-purpose processors, integrated circuits, ASICs (Application Specific Integrated Circuits), conventional circuits, and / or combinations thereof, configured or programmed to perform the disclosed functions. A processor is considered a processing circuit or circuit because it includes transistors and other circuitry. In this disclosure, a circuit, unit, or means is hardware that performs the recited functions or hardware that is programmed to perform the recited functions. The hardware may be hardware disclosed herein or other known hardware that is programmed or configured to perform the recited functions. Where the hardware is a processor, which is considered a type of circuit, the circuit, means, or unit is a combination of hardware and software, and the software is used to configure the hardware and / or processor.

[0048] Aspects It will be appreciated by those skilled in the art that the exemplary embodiments described above are examples of the following aspects.

[0049] (Mode 1) A robot system comprising: a robot arm; a hand attached to the robot arm and configured to hold a workpiece; a container including a workpiece storage space surrounded by a pair of first inclined surfaces whose lower edge portions meet on a line extending in a predetermined direction when viewed from above, and a pair of second inclined surfaces each having a pair of edges connected to the ends of the lower edge portions of the pair of first inclined surfaces; and a control unit that executes control to cause the hand to hold the workpiece placed in the workpiece storage space of the container.

[0050] (Aspect 2) The robot system according to aspect 1, wherein the pair of first inclined surfaces has a trapezoidal shape, and the pair of second inclined surfaces has a triangular shape.

[0051] (Aspect 3) The robot system according to Aspect 1 or Aspect 2, wherein the hand includes a chuck that opens and closes along the predetermined direction, and a length of a range of opening and closing of the chuck along the predetermined direction is equal to or greater than a length of a side of a lower end of the first inclined surface.

[0052] (Aspect 4) In the robot system according to aspect 3, the control unit executes a process of causing the chuck to hold the workpiece placed at a position where the lower edges of the pair of first inclined surfaces are in contact with each other.

[0053] (Aspect 5) A robot system according to Aspect 4, further comprising an imaging unit that captures a two-dimensional image of the workpiece placed in the container, wherein the control unit, when determining based on the image captured by the imaging unit that the workpiece is placed at a position shifted from the position where the lower end edges of the pair of first inclined surfaces contact each other, executes a process of moving the workpiece by the chuck to the position where the lower end edges of the pair of first inclined surfaces contact each other.

[0054] (Aspect 6) A robot system according to Aspect 4 or Aspect 5, further comprising an imaging unit that captures a two-dimensional image of the workpiece placed in the container, wherein the control unit, when determining based on the image captured by the imaging unit that the workpiece is placed at a position where the pair of first inclined surfaces and the second inclined surface are in contact, executes a process of moving the workpiece by the chuck to a position where the lower edges of the pair of first inclined surfaces are in contact with each other.

[0055] (Aspect 7) A robot system according to any one of Aspects 1 to 6, wherein the container includes a marker arranged across the pair of first inclined surfaces and the pair of second inclined surfaces, and the robot system further includes an imaging unit that captures two-dimensional images of the workpiece and the marker placed on the container, and the control unit determines whether the workpiece is placed on the marker based on the image captured by the imaging unit.

[0056] (Aspect 8) In the robot system according to aspect 7, when it is determined that the workpiece is not placed on the marker, the control unit causes the robot arm to execute an operation of replenishing the workpiece.

[0057] (Aspect 9) The robot system according to Aspect 7 or Aspect 8, wherein the mark includes paint applied to the container, and a color of the mark is different from a color of the pair of first inclined surfaces and a color of the pair of second inclined surfaces.

[0058] (Aspect 10) The robot system according to any one of Aspects 1 to 9, further comprising: a carriage unit on which the robot arm is placed; and a movement unit that moves the carriage unit, wherein the control unit executes a process of moving the robot arm to a position near the container using the movement unit.

Claims

1. A robot system comprising: a robot arm; a hand attached to the robot arm and configured to hold a workpiece; a container including a workpiece storage space surrounded by a pair of first inclined surfaces whose lower edges meet on a line extending in a predetermined direction when viewed from above, and a pair of second inclined surfaces, each of which has a pair of edges connected to ends of the lower edges of the pair of first inclined surfaces; and a control unit that executes control to cause the hand to hold the workpiece placed in the workpiece storage space of the container.

2. The robot system according to claim 1, wherein the pair of first inclined surfaces has a trapezoidal shape, and the pair of second inclined surfaces has a triangular shape.

3. The robot system according to claim 1, wherein the hand includes a chuck that opens and closes along the predetermined direction, and the length of the range of opening and closing of the chuck along the predetermined direction is equal to or greater than the length of the lower edge of the first inclined surface.

4. A robot system as described in claim 3, wherein the control unit executes a process of holding the workpiece, which is placed at a position where the lower edges of the pair of first inclined surfaces are in contact with each other, by the chuck.

5. A robot system as described in claim 4, further comprising an imaging unit which captures a two-dimensional image of the workpiece placed in the container, and when the control unit determines based on the image captured by the imaging unit that the workpiece is placed in a position shifted from the position where the lower edges of the pair of first inclined surfaces contact each other, it executes a process of moving the workpiece by the chuck to the position where the lower edges of the pair of first inclined surfaces contact each other.

6. A robot system as described in claim 4, further comprising an imaging unit which captures a two-dimensional image of the workpiece placed in the container, and when the control unit determines based on the image captured by the imaging unit that the workpiece is placed at a position where the pair of first inclined surfaces and the second inclined surface are in contact, it executes a process of moving the workpiece by the chuck to a position where the lower edges of the pair of first inclined surfaces are in contact.

7. The robot system of claim 1, wherein the container includes a marker arranged across the pair of first inclined surfaces and the pair of second inclined surfaces, and the robot system is equipped with an imaging unit that captures two-dimensional images of the workpiece and the marker placed on the container, and the control unit determines whether or not the workpiece is placed on the marker based on the image captured by the imaging unit.

8. A robot system as described in claim 7, wherein the control unit, when determining that the workpiece is not placed on the marker, causes the robot arm to execute an operation to replenish the workpiece.

9. The robot system according to claim 7, wherein the marker includes paint applied to the container, and a color of the marker is different from a color of the pair of first inclined surfaces and a color of the pair of second inclined surfaces.

10. The robot system according to claim 1, comprising: a cart unit on which the robot arm is placed; and a movement unit that moves the cart unit, wherein the control unit executes a process of moving the robot arm to the vicinity of the container using the movement unit.

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