Robot system and robot control method

Abstract

To pack objects in a general container in a stable state.SOLUTION: A robot system 1 has: a robot 9 which transfers strawberries 5 held in a tray 3 to a pack 7; a movable mount table 13 on which the pack 7 is mounted and which is inclined to a horizontal surface at least in a front-rear direction; a tray camera 21 and a pack camera 23 which detect information associated with the tray 3 and pack 7; and a robot control part 41 of a higher controller 27 which controls the robot 9 to pack and place the strawberries 5, held by the robot 9, on an inclined mount surface 7a of the pack 7 from the lower side.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The disclosed embodiments relate to a robot system and a robot control method. [Background technology]

[0002] Patent document 1 describes a fruit and vegetable transport device that holds and transports fruit and vegetables arranged on a harvest tray without damaging them, sorts them into classes, and packs them into designated storage packs. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2002-52487 A Summary of the Invention [Problem to be solved by the invention]

[0004] The above-mentioned conventional fruit and vegetable transport device packs the fruit and vegetables on the harvest tray into a special storage pack with an uneven surface for placing the fruit and vegetables side by side at an angle. In this case, many different types of storage packs are used depending on the type, size, shape, etc. of the fruit and vegetables, which increases the installation space and cost of the storage packs. For this reason, there has been a demand for a system that can pack the target items into general-purpose containers in a stable state.

[0005] The present invention has been made in consideration of these problems, and has an object to provide a robot system and a robot control method that are capable of stably packing objects into general-purpose containers. [Means for solving the problem]

[0006] In order to solve the above problem, according to one aspect of the present invention, a robot system is applied, which includes a robot that transfers an object contained in a first container to a second container, a mounting section on which the second container is placed and which is inclined in at least a first direction with respect to a horizontal plane, a detector that detects information regarding the first container and the second container, and a robot control section that controls the robot so that the object held by the robot is packed and placed on the inclined mounting surface of the second container from below.

[0007] According to another aspect of the present invention, a robot system is provided that includes a robot that transfers an object contained in a first container to a second container, a detector that detects information about the first container and the second container, a storage planning unit that plans a storage state of the object in the second container based on a detection state of the object contained in the first container detected by the detector, a state detection unit that detects a state of the object held by the robot, a quality judgment unit that judges the quality of the object based on the detection state of the object in at least one of the detector and the state detection unit, a temporary placement unit on which the object that does not conform to the storage state plan is temporarily placed, and a robot control unit that controls the robot to hold the object contained in the first container, based on the storage state plan, through a judgment of the quality in the quality judgment unit, and then placed in the second container.

[0008] According to another aspect of the present invention, a robot control method is applied that controls a robot that transfers an object contained in a first container to a second container, the method comprising: controlling the robot so that the object held by the robot is placed from below on an inclined support surface of the second container, the second container being placed on a support section that is inclined in at least a first direction with respect to a horizontal plane, based on information about the first container and the second container detected by a detector.

[0009] According to another aspect of the present invention, there is provided a robot control method for controlling a robot of a robot system having a robot that transfers an object contained in a first container to a second container, a detector that detects information relating to the first container and the second container, a storage planning unit that plans a storage state of the object in the second container based on a detection state of the object contained in the first container detected by the detector, a state detection unit that detects a state of the object held by the robot, and a quality judgment unit that judges the quality of the object based on the detection state of the object in at least one of the detector and the state detection unit, the robot control method comprising the steps of: temporarily placing the object that does not conform to the storage state plan on a temporary placement unit, and controlling the robot to hold the object contained in the first container, based on the storage state plan, through a judgment of the quality in the quality judgment unit, and then placing it in the second container. Effect of the Invention

[0010] According to the robot system etc. of the present invention, an object can be packed in a general-purpose container in a stable state. [Brief description of the drawings]

[0011] [Figure 1] 1 is a system configuration diagram illustrating an example of an overall configuration of a robot system. [Diagram 2] FIG. 2 is a block diagram illustrating an example of a functional configuration of a higher-level control device. [Diagram 3] FIG. 1 is a diagram showing an example of grading standards for strawberries. [Figure 4] 13 is a diagram showing a specific example of a storage pattern of strawberries in a pack planned by a storage planning unit. FIG. [Diagram 5] 13 is a diagram showing a specific example of a storage pattern of strawberries in a pack planned by a storage planning unit. FIG. [Figure 6] 10 is an explanatory diagram showing a specific example of position control when packing strawberries into containers. FIG. [Figure 7]10 is an explanatory diagram showing a specific example of position control when packing strawberries into containers. FIG. [Figure 8] 11A and 11B are diagrams illustrating a configuration of a movable stage and a specific example of tilt control by a tilt control unit. [Figure 9] 11A and 11B are diagrams illustrating a configuration of a movable stage and a specific example of tilt control by a tilt control unit. [Figure 10] 4 is a flowchart illustrating an example of a processing procedure executed by a higher-level control device. [Figure 11] 13 is a flowchart illustrating an example of detailed contents of an accommodation planning process. [Figure 12] 13 is a flowchart illustrating an example of details of a remaining amount transfer process. [Figure 13] FIG. 13 is a diagram illustrating an example of the configuration of a robot system according to a modified example that detects the posture of a strawberry held by the robot. [Figure 14] 13 is a flowchart illustrating an example of a processing procedure executed by a host control device in a modified example for detecting the posture of a strawberry held by a robot. [Figure 15] FIG. 2 is a block diagram illustrating an example of a hardware configuration of a higher-level control device. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0012] Hereinafter, an embodiment will be described with reference to the drawings. In the embodiment, directions such as up, down, left, right, front, back, etc. may be appropriately used for convenience in explaining the configuration of a robot system, etc., but this does not limit the orientation or position of each component.

[0013] <1. Robot system configuration> An example of the configuration of a robot system 1 according to an embodiment will be described with reference to FIG.

[0014] The robot system 1 is a system for transferring objects 5 stored in a tray 3 to a pack 7 and packing them into containers. There are no particular limitations on the objects 5 as long as they are objects to be packed into containers. For example, the objects 5 may be fruits and vegetables, fresh foods, processed foods, food ingredients, confectioneries, etc. Alternatively, the objects 5 may be industrial products such as machine parts and electronic parts. In the embodiment, a case will be described in which the objects 5 are, for example, strawberries (suitably referred to as "strawberries 5").

[0015] As shown in FIG. 1, the robot system 1 includes a robot 9, a force sensor 10, a weight scale 11, a movable platform 13, a temporary platform 15, a mirror 17, a waste box 19, a tray camera 21, a pack camera 23, a robot camera 25, a host control device 27, and a robot controller 29.

[0016] The tray 3 (an example of a first container) is a container from which the object 5 to be packed is transferred, and in the embodiment, is a container in which a plurality of strawberries 5 are stored. The tray 3 is preferably a box-shaped container without a lid, such as a food box. For example, the strawberries 5 are stored in the tray 3 with the tip side opposite to the stem facing upward. The strawberries 5 may also be stored with the stem side facing upward. The tray 3 is carried into the robot system 1 with the strawberries 5 stored therein, and is carried out from the robot system 1 when it is empty. The tray 3 may be carried in and out by a worker, a transport device such as a conveyor, or the robot 9 or another robot. The tray 3 is disposed near the robot 9 (for example, on the left side).

[0017] The pack 7 (an example of a second container) is a container to which the object 5 to be packed is transferred, and in the embodiment, is a container made of, for example, polystyrene foam in which a plurality of strawberries 5 are accommodated. The pack 7 is a thin container having a flat placement surface 7a on which the strawberries 5 are placed, and is configured as a general-purpose container capable of accommodating strawberries 5 of various shapes or sizes. For example, the strawberries 5 are placed in the pack 7 with the tip side opposite to the stem facing upward. The strawberries 5 may be placed with the stem side facing upward. The pack 7 may be configured to accommodate a wide variety of objects other than strawberries. As an example, the pack 7 is placed on a pack stand 8 made of, for example, transparent resin. The pack stand 8 may be omitted, and the pack 7 may be placed directly on the movable placement table 13. The pack 7 is carried into the robot system 1 in an empty state, and is carried out from the robot system 1 in a state in which the strawberries 5 transferred from the tray 3 are accommodated and packed in the container. The packs 7 may be carried in and out by a worker, by a transport device such as a conveyor, or by the robot 9 or another robot. The packs 7 are disposed near the robot 9 (for example, on the right front side).

[0018] The robot 9 is disposed at approximately the center of the robot system 1, and transfers the strawberries 5 contained in the tray 3 to the packs 7. As an example, the robot 9 includes a vertical multi-joint arm 9a having, for example, six joints, and an end effector capable of holding the strawberries 5. In the embodiment, a suction hand 31 that suctions and holds the strawberries 5 is provided as the end effector. The end effector may be a gripper that grasps an object. The robot 9 may be a vertical multi-joint type other than six axes (for example, five axes or seven axes), or may be a horizontal multi-joint type. The robot 9 may be a general-purpose robot, or may be a dedicated working machine designed specifically for container filling work, equipped with an actuator that can move in XYZθ directions, such as a gantry mechanism.

[0019] The force sensor 10 is installed between the tip of the arm 9a of the robot 9 and the suction hand 31. The force sensor 10 is, for example, a six-axis force sensor, and detects the force components in the directions of the X-axis, Y-axis, and Z-axis, and the torque components acting around each axis, thereby detecting the reaction force that the suction hand 31 receives from the outside. The detection information of the force sensor 10 is transmitted to a higher-level control device 27.

[0020] The weighing scale 11 is disposed below the tray 3, and the tray 3 is placed on top of it. The weighing scale 11 measures the total weight of the tray 3, including the weight of the strawberries 5 contained therein, and transmits the measurement information to a higher-level control device 27. The higher-level control device 27 calculates the actual weight of the strawberries 5 held by the robot 9 based on the measurements of the weighing scale 11 before and after the robot 9 holds the strawberries 5.

[0021] The movable mounting table 13 (an example of a mounting section) includes a table 13a on which the pack stand 8 and the pack 7 are mounted. The movable mounting table 13 includes actuators 13A and 13B (see Figs. 8 and 9 described later) for tilting the table 13a, and is configured to be able to tilt the table 13a in the front-rear direction (an example of a first direction) and the left-right direction (an example of a second direction) with respect to a horizontal plane. This causes the mounting surface 7a of the pack 7 to be tilted in the front-rear direction and the left-right direction. The actuators 13A and 13B are controlled by a higher-level control device 27. In the embodiment, the front-rear direction corresponds to the longitudinal direction of the pack 7, and the left-right direction corresponds to the lateral direction of the pack 7. Fig. 1 shows a state in which the movable mounting table 13 tilts the mounting surface 7a of the pack 7 in the front-rear direction. The table 13a is provided with stoppers 13b for preventing the pack stand 8 from slipping at positions that become the lower side when tilted, for example, at the front side in the front-rear direction and at the left side in the left-right direction. The movable stage 13 may be configured to be tiltable only in the front-rear direction. Also, it does not necessarily have to be movable, and the table 13a may be a stage that is fixedly tilted with respect to the horizontal plane.

[0022] The temporary placement table 15 (an example of a temporary placement section) is a table on which the strawberries 5 are temporarily placed. Although details will be described later, if the strawberries 5 held by the robot 9 on the tray 3 do not meet a predetermined standard (for example, the weight or grade of the strawberries 5), the robot 9 temporarily places the strawberries 5 on the temporary placement table 15 without transferring them to the packs 7. A predetermined number of recesses 15a are formed on the temporary placement table 15 for placing the strawberries 5 individually. The temporary placement table 15 may have a flat placement surface similar to the packs 7, or may be a box-shaped container. The temporary placement table 15 is located near the robot 9 (for example, on the left front) on the transfer path along which the strawberries 5 are transferred from the tray 3 to the packs 7.

[0023] A plurality of mirrors 17 (for example, five mirrors) are arranged so as to reflect the state of the strawberry 5 held by the robot 9 at a predetermined inspection position from a plurality of directions (for example, five directions). The state of the strawberry 5 reflected by the mirror 17 is, for example, the shape and size of the underside (the surface on the stem side) and sides of the strawberry 5, the presence or absence of scratches or insect bites, etc. The number of mirrors may be one or more than five. Images reflected by the plurality of mirrors 17 are captured by a robot camera 25 provided on the robot 9. The mirror 17 is arranged near (for example, in front of) the robot 9 on the way of the transfer path for transferring the strawberry 5 from the tray 3 to the pack 7. The upper control device 27 judges the quality of the strawberry 5 held by the robot 9 based on the image captured by the robot camera 25.

[0024] The waste box 19 is a container in which strawberries 5 of poor quality are discarded. When the upper control device 27 judges that the strawberries 5 are of poor quality, the robot 9 transfers the strawberries 5 to the waste box 19 (an example of a place other than the first container and the second container) without transferring them to the packs 7. The waste box 19 is configured as, for example, a box-shaped container, and is carried into the robot system 1 in an empty state, and is carried out from the robot system 1 when a predetermined amount of discarded strawberries 5 is reached. The carrying in and carrying out of the waste box 19 may be performed by an operator, may be performed by a transport device such as a conveyor, or may be performed by the robot 9 or another robot. The waste box 19 is disposed near the robot 9 (for example, on the right side). The waste box 19 may not be a container, but may be a chute or transport device for transporting the strawberries 5 to a predetermined waste place.

[0025] The tray camera 21 (an example of a detector) is disposed above or diagonally above the tray 3, and captures an image of the tray 3 to detect information related to the tray 3. As an example, the tray camera 21 captures an image of the strawberries 5 contained in the tray 3 to detect the number, arrangement, state, etc. of the strawberries 5 contained therein. The state of the strawberries 5 detected by the tray camera 21 is, for example, the shape and size of the top surface of the strawberry 5 (the surface on the tip side opposite the stem), the presence or absence of scratches or insect bites, etc. The image captured by the tray camera 21 is transmitted to the upper control device 27. The tray camera 21 may be a 2D camera or a 3D camera, but a 3D camera capable of acquiring information in the depth direction is preferable.

[0026] Pack camera 23 (an example of a detector) is disposed above or diagonally above pack 7, and captures an image of pack 7 to detect information about pack 7. As one example, pack camera 23 captures an image of strawberries 5 placed on pack 7 to detect the number, arrangement, etc. of strawberries 5 placed. As another example, when strawberries 5 are placed at a predetermined position in pack 7, pack camera 23 captures an image of the distance from strawberry 5 held by robot 9 to the predetermined position. The image captured by pack camera 23 is transmitted to upper control device 27. Pack camera 23 may be a 2D camera or a 3D camera, but a 3D camera capable of acquiring information in the depth direction is preferable.

[0027] The robot camera 25 (an example of a state detection unit) is disposed near the tip of the arm 9a of the robot 9, and detects the state of the strawberries 5 by capturing an image of the tip side of the suction hand 31. As an example, the robot camera 25 detects the state of the strawberries 5 in the tray 3 that the robot 9 is to hold, and the state of the strawberries 5 held by the robot 9 at a predetermined inspection position through the mirror 17. The state of the strawberries 5 to be held is, for example, the shape, size, and presence or absence of scratches or insect marks on the top surface of the strawberry 5 (which may be the surface on the tip side opposite the stem, or the surface on the stem side). The state of the strawberries 5 held at the inspection position is, for example, the shape, size, and presence or absence of scratches or insect marks on the bottom surface of the strawberry 5 (which may be the surface on the stem side, or the surface on the tip side opposite the stem) and sides. The image captured by the robot camera 25 is transmitted to the upper control device 27. The robot camera 25 may be a 2D camera or a 3D camera, but a 3D camera capable of acquiring information in the depth direction is preferable.

[0028] The host controller 27 receives measurement information from the weighing scale 11, detection information from the force sensor 10, images captured by the tray camera 21, images captured by the pack camera 23, images captured by the robot camera 25, etc., and executes various processes based on the information. The host controller 27 transmits commands based on the results of the various processes to the robot controller 29. The host controller 27 is composed of, for example, a personal computer (PC), a motion controller, a programmable logic controller (PLC), etc.

[0029] The robot controller 29 controls the robot 9 based on commands from the upper control device 27. The robot controller 29 includes a servo amplifier 53 (see FIG. 2) that supplies driving power to the robot 9. The robot controller 29 controls the operation of the robot 9 by controlling the driving of a plurality of motors M1 to M6 (see FIG. 2) provided on the robot 9. The robot controller 29 may be disposed integrally with the robot 9 or may be disposed separately.

[0030] The configuration of the robot system 1 described above is an example, and is not limited to the above. For example, the locations of the tray 3 and the pack 7 may be swapped, or the locations of the temporary placement table 15 and the mirror 17 may be swapped, and other arrangements of the devices may be changed. The mirror 17 may be a camera or a sensor capable of detecting the state of the strawberries 5. At least one of the tray camera 21, the pack camera 23, and the robot camera 25 may be a sensor other than a camera capable of detecting the arrangement, shape, state, etc. of the strawberries 5. Instead of or in addition to the robot camera 25, a fixed camera (not shown) capable of capturing an image of the mirror 17 (an example of a state detection unit) may be installed.

[0031] <2. Functional configuration of the host control device> An example of the functional configuration of the upper controller 27 will be described with reference to FIG.

[0032] As shown in FIG. 2, the upper control device 27 has a grade determination unit 33, a weight estimation unit 35, a storage planning unit 37, a quality determination unit 39, a robot control unit 41, a weight measurement unit 43, a weight determination unit 45, a contact detection unit 47, and a tilt control unit 49.

[0033] The grade determination unit 33 determines the grade of the strawberries 5 stored in the tray 3 based on the captured image of the strawberries 5 stored in the tray 3 by the tray camera 21 (an example of the detection state of the object) and the grade standard of the strawberries 5 (an example of a predetermined standard related to the state of the object). The grade standard may be stored in an appropriate storage unit (e.g., the recording device 917, etc., see FIG. 15) of the upper control device 27, or may be acquired from an external device. FIG. 3 shows an example of the grade standard. As shown in FIG. 3, a plurality of grades A, B, and C are defined according to the shape of the strawberries 5. In the example shown in FIG. 3, grade A is the highest grade, grade C is the lowest grade, and grade B is intermediate between them. The grade determination unit 33 extracts the shape of each strawberry 5 by performing a predetermined image processing on the captured image by the tray camera 21, and compares it with the grade standard by, for example, pattern matching processing, etc., to determine the grade of each strawberry 5 for all the strawberries 5 stored in the tray 3. The grade determination unit 33 may include a learning model that has previously learned to determine grades by machine learning, deep learning, or the like, using, for example, captured images and actual grades.

[0034] The weight estimation unit 35 calculates an estimated weight for each strawberry 5 based on an image of the strawberries 5 stored in the tray 3 captured by the tray camera 21. As an example, the weight estimation unit 35 extracts the volume of each strawberry 5 by performing a predetermined image processing on the image captured by the tray camera 21, and multiplies the volume by the density of the strawberries 5 to calculate an estimated weight for each strawberry 5 for all the strawberries 5 stored in the tray 3. The density of the strawberries 5 may be stored in an appropriate storage unit (e.g., the recording device 917, etc. See FIG. 15) of the upper control device 27, or may be acquired from an external device. Note that the density of the strawberries 5 may use different values ​​depending on the season or time of year. The weight estimation unit 35 may include a learning model that has previously learned weight estimation by machine learning, deep learning, or the like using the captured image and the measured actual weight.

[0035] The storage planning unit 37 plans the storage state of the strawberries 5 in the pack 7 based on the image of the strawberries 5 stored in the tray 3 captured by the tray camera 21. The storage state includes, for example, the total weight of the pack 7 after storage is completed, the arrangement, grade, number of strawberries 5, etc. As an example, the storage planning unit 37 plans the storage state so that the total weight (accumulated estimated weight) of the pack 7 after storing the strawberries 5 is within a predetermined specified weight range. As another example, the storage planning unit 37 plans the storage state so that strawberries 5 of a common grade are stored in each pack 7. For example, in the case of the grades shown in FIG. 3, the storage is planned so that only one type of strawberries 5, grade A, grade B, or grade C, is stored in one pack 7, that is, two or more types of grades A, grade B, and grade C are not mixed in one pack 7. As yet another example, when there are strawberries 5 temporarily placed on the temporary placement table 15, the storage planner 37 plans a storage mode such that the strawberries 5 temporarily placed on the temporary placement table 15 are preferentially stored in the pack 7 over the strawberries 5 stored in the tray 3. As a result, the robot control unit 41 controls the robot 9 to hold the strawberries 5 temporarily placed on the temporary placement table 15 preferentially over the strawberries 5 stored in the tray 3. The storage planner 37 may include a learning model that learns a storage plan in advance by machine learning, deep learning, or the like using, for example, the captured image and the storage mode planned by the worker. Note that, as the storage mode, a plurality of patterns including elements such as the total weight, arrangement, grade, and number may be set in advance, and may be stored in an appropriate storage unit (for example, the recording device 917, etc.; see FIG. 15) of the upper control device 27, or may be acquired from an external device. In this case, the storage planner 37 may plan the storage mode by selecting one of the patterns based on the captured image by the tray camera 21.

[0036] 4 and 5 show specific examples of the storage state of strawberries 5 in packs 7 planned by the storage planning unit 37. Fig. 4 shows a case where the strawberries 5 are relatively large, for example, a case where eight grade A strawberries 5 are planned to be stored. Fig. 5 shows a case where the strawberries 5 are relatively small, for example, a case where twelve grade A strawberries 5 are planned to be stored. In either case, the total weight is planned to be within a predetermined specified weight range (for example, 260g to 270g).

[0037] Returning to FIG. 2, the quality determination unit 39 (an example of a determination unit) determines whether the strawberries 5 held by the robot 9 satisfy a predetermined standard. As an example, the quality determination unit 39 determines whether the quality of the strawberries 5 (an example of a predetermined standard) is good or bad based on an image of the strawberries 5 held by the robot 9 captured by the robot camera 25 through the mirror 17. As another example, the quality determination unit 39 may determine whether the quality of the strawberries 5 is good or bad based on an image of the strawberries 5 in the tray 3 that the robot 9 is to hold captured by the robot camera 25. As yet another example, the quality determination unit 39 may determine whether the quality of the strawberries 5 contained in the tray 3 is good or bad based on an image captured by the tray camera 21. The quality determination unit 39 may include a learning model that has previously learned quality determination by machine learning, deep learning, or the like using, for example, the captured image and the actual quality.

[0038] The robot control unit 41 controls the operation of the robot 9 by transmitting a position command indicating, for example, the hand position of the arm 9a of the robot 9 (the position of the suction hand 31) to the robot controller 29. As one example, the robot control unit 41 controls the robot 9 so that the strawberries 5 held by the robot 9 are packed from the bottom onto the inclined placement surface 7a of the pack 7. As another example, the robot control unit 41 controls the robot 9 so that the strawberries 5 are transferred to the pack 7 based on the storage plan planned by the storage plan unit 37. As yet another example, the robot control unit 41 controls the robot 9 so that the strawberries 5 held by the robot 9 are moved to an inspection position above the mirror 17, and if the quality of the strawberries 5 is determined to be good by the quality determination unit 39, the robot control unit 41 controls the robot 9 so that the strawberries 5 are transferred to the pack 7, and if the quality of the strawberries 5 is determined to be bad, the robot control unit 41 controls the robot 9 so that the strawberries 5 are transferred to the waste box 19.

[0039] The weight measuring unit 43 measures the actual weight of the strawberries 5 held by the robot 9. As an example, the weight measuring unit 43 calculates the actual weight of the strawberries 5 held by the robot 9 by subtracting the measurement value of the weight scale 11 after the robot 9 holds the strawberries 5 from the measurement value of the weight scale 11 before the robot 9 holds the strawberries 5 on the tray 3.

[0040] The weight determination unit 45 (an example of a determination unit) determines whether the strawberries 5 held by the robot 9 satisfy a predetermined standard. As an example, the weight determination unit 45 calculates the difference between the estimated weight calculated by the weight estimation unit 35 and the actual weight calculated by the weight measurement unit 43 for the strawberries 5 held by the robot 9, and determines whether the difference is greater than a predetermined threshold value (an example of a predetermined standard). When the weight determination unit 45 determines that the difference is greater than the predetermined threshold value, the robot control unit 41 controls the robot 9 to transfer the strawberries 5 to the temporary placement table 15 (an example of a place other than the first container and the second container). In the embodiment, when the weight determination unit 45 determines that the difference is greater than the predetermined threshold value and the quality determination unit 39 determines that the quality of the strawberries 5 is good, the robot control unit 41 controls the robot 9 to transfer the strawberries 5 to the temporary placement table 15.

[0041] The contact detection unit 47 detects contact between the strawberry 5 held by the robot 9 and another object based on detection information by the force sensor 10 when the robot 9 places the strawberry 5 on the placement surface 7a of the pack 7. The other object includes other strawberries 5 already placed on the placement surface 7a of the pack 7 and the inner wall 7b of the pack 7. The robot control unit 41 switches the control of placing the strawberry 5 from position control to force control at the timing when the contact is detected by the contact detection unit 47. The force control may be controlled based on detection information by the force sensor 10. Note that the contact detection unit 47 may detect contact when the strawberry 5 held by the robot 9 approaches another object to a distance close to 0 based on, for example, an image captured by the robot camera 25 or the pack camera 23 instead of or in addition to the detection information by the force sensor 10. In this case, the force sensor 10 may be omitted. In addition, the contact detection unit 47 detects contact between the strawberry 5 to be held and the suction hand 31 when the robot 9 holds the strawberry 5 from the tray 3. After detecting the contact, the robot 9 starts the suction operation of the suction hand 31 to hold the strawberry 5 .

[0042] 6 and 7 show a specific example of placing strawberries 5 in a pack 7. Figs. 6 and 7 correspond to the storage mode in which, for example, eight strawberries 5 shown in Fig. 4 are stored. In Figs. 6 and 7, the first strawberry 5 to be placed is indicated by reference numeral 5(1), the second strawberry 5 to be placed is indicated by reference numeral 5(2), the third strawberry 5 to be placed is indicated by reference numeral 5(3), and the fourth strawberry 5 to be placed is indicated by reference numeral 5(4). Also, in Figs. 6 and 7, illustrations of robots 9 such as suction hands 31 are omitted.

[0043] The robot control unit 41 performs position control on the robot 9 so that the first strawberry 5(1) is placed at the left front corner position of the pack 7. In the position control, the robot control unit 41 calculates the distance to the target position where the strawberry 5 is to be placed based on the image captured by the pack camera 23, and controls the robot 9 so that the calculated distance becomes approximately zero (visual feedback control). Furthermore, if the robot control unit 41 detects contact with another strawberry 5 or the inner wall 7b of the pack 7 while moving the strawberry 5 to the target position, it switches from position control to force control. In the force control, the strawberry 5 is placed at the target position while moving the strawberry 5 a predetermined distance in the direction opposite to the contact direction (the direction to escape from the force of contact). When the robot control unit 41 detects that the strawberry 5(1) has contacted both the left inner wall 7b and the front inner wall 7b, it switches from position control to force control and gently places the strawberry 5(1) at the left front corner position of the pack 7 so as not to apply a force of a predetermined magnitude or more. Similarly, the robot control unit 41 performs position control on the robot 9 so as to place the second strawberry 5(2) in the front right corner of the pack 7, and when it detects that the strawberry 5(2) has come into contact with both the right inner wall 7b and the front inner wall 7b, it switches from position control to force control and gently places the strawberry 5(2) in the front right corner of the pack 7 without applying more than a predetermined amount of force.

[0044] FIG. 6 is an example of placing the third strawberry 5(3). As shown in FIG. 6, the robot control unit 41 calculates the closest point between the contours of the first strawberry 5(1) and the second strawberry 5(2) and the contour of the third strawberry 5(3), and performs position control on the robot 9 so as to move the strawberry 5(3) forward along the placement surface 7a while maintaining a position where the distances d1 and d2 between those points are equal based on the image captured by the pack camera 23. When the robot control unit 41 detects that the strawberry 5(3) has come into contact with both the strawberry 5(1) and the strawberry 5(2), it switches from position control to force control and gently places the strawberry 5(3) against the strawberry 5(1) and the strawberry 5(2) without pressing the strawberry 5(3) with a force of a predetermined magnitude or more. In addition, when performing position control, the robot 9 may be controlled based on an image captured by the robot camera 25 instead of or in addition to the pack camera 23.

[0045] FIG. 7 is an example of placing the fourth strawberry 5(4). As shown in FIG. 7, the robot control unit 41 performs position control on the robot 9 so that the distance d3 between the fourth strawberry 5(4) and the left inner wall 7b becomes a predetermined distance close to 0 based on the image captured by the pack camera 23, and the strawberry 5(4) moves forward along the placement surface 7a while maintaining the distance. When the robot control unit 41 detects that the strawberry 5(4) has come into contact with both the strawberry 5(3) and the left inner wall 7b, it switches from position control to force control and gently places the strawberry 5(4) against the strawberry 5(3) and the left inner wall 7b without pressing the strawberry 5(4) with a force of a predetermined magnitude or more. In addition, when performing position control, the robot 9 may be controlled based on an image captured by the robot camera 25 instead of or in addition to the pack camera 23.

[0046] The fifth strawberry 5(5) is placed in the same manner as the fourth strawberry 5(4). That is, the robot control unit 41 performs position control on the robot 9 so that the distance between the fifth strawberry 5(5) and the right inner wall 7b becomes a predetermined distance close to 0 based on the image captured by the pack camera 23, and the strawberry 5(5) moves forward along the placement surface 7a while maintaining the distance. When the robot control unit 41 detects that the strawberry 5(5) has come into contact with both the strawberry 5(3) and the right inner wall 7b, it switches from position control to force control, and gently places the strawberry 5(5) against the strawberry 5(3) and the right inner wall 7b without pressing the strawberry 5(5) with a force of a predetermined magnitude or more. The sixth to eighth strawberries 5 are placed in the same manner as the third to fifth strawberries 5 described above. In addition, when performing position control, the robot 9 may be controlled based on an image captured by the robot camera 25 instead of or in addition to the pack camera 23.

[0047] Returning to FIG. 2, the tilt control unit 49 controls the tilt of the movable placement table 13 so that the tilt angle in the left-right direction is changed according to the placement position when the strawberry 5 held by the robot 9 is placed on the placement surface 7a of the pack 7. FIGS. 8 and 9 show the configuration of the movable placement table 13 and a specific example of tilt control by the tilt control unit 49. In FIGS. 8 and 9, the first strawberry 5 to be placed is indicated by the reference symbol 5(1), the second strawberry 5 to be placed is indicated by the reference symbol 5(2), and the third strawberry 5 to be placed is indicated by the reference symbol 5(3). As an example, each strawberry 5 is placed with the tip opposite the stem facing upward and the tip tilted downward (forward) from the vertically upward direction.

[0048] As shown in Figures 8 and 9, the movable table 13 has a table 13a, an intermediate table 13c, a base 13d, and actuators 13A and 13B. The table 13a and the intermediate table 13c are tilted in the front-rear direction by the actuator 13A via a rotating shaft 13e provided at the front end of the base 13d. The table 13a is tilted in the left-right direction by the actuator 13B via a rotating shaft 13f provided at the left end of the intermediate table 13c. The actuators 13A and 13B are not particularly limited, and any suitable type of actuator can be used, such as a pantograph type, a shaft delivery type, or a type that rotates and drives the rotating shafts 13e and 13f.

[0049] FIG. 8 is an example of the case where, for example, eight strawberries 5 shown in FIG. 4 are stored. As shown in FIG. 8, when the first strawberry 5(1) is placed at the left front corner position of the pack 7, the tilt control unit 49 controls the movable placement table 13 so that the left front corner position of the pack 7 is the lowest by tilting the table 13a by a predetermined angle in the left-right direction in addition to the front-rear direction. This makes it possible to make the strawberry 5(1) less likely to roll by utilizing its own weight. Next, the tilt control unit 49 controls the movable placement table 13 so that the left-right tilt of the table 13a is set to 0 before the second strawberry 5(2) is placed at the right front corner position of the pack 7, so that the pack 7 is inclined only in the front-rear direction. In this state, the strawberry 5(2) is placed at the right front corner position of the pack 7. This allows the strawberry 5(2) to be placed at the right front corner position while leaving a gap between the strawberry 5(1) and the strawberry 5(2). Thereafter, the tilt control unit 49 maintains the state in which the pack 7 is tilted only in the front-rear direction while keeping the left-right tilt of the table 13a at zero. In this state, the third and subsequent strawberries 5 are placed one after another. In this way, eight strawberries 5 are placed on the inclined placement surface 7a of the pack 7, packed from the bottom up.

[0050] FIG. 9 is an example of the case where, for example, the twelve strawberries 5 shown in FIG. 5 are stored. As shown in FIG. 9, when the first strawberry 5(1) is placed at the left front corner position of the pack 7, the tilt control unit 49 controls the movable placement platform 13 so that the left front corner position of the pack 7 is lowest by tilting the table 13a by a predetermined angle in the left-right direction in addition to the front-rear direction. This makes it difficult for the strawberry 5(1) to roll by utilizing its own weight. Next, when the second strawberry 5(2) is placed to the right of the strawberry 5(1), the tilt control unit 49 maintains the tilted state of the table 13a. This makes it difficult for the strawberry 5(2) to roll by utilizing its own weight. Next, before the third strawberry 5(3) is placed at the right front corner position of the pack 7, the tilt control unit 49 controls the movable placement platform 13 so that the tilt in the left-right direction of the table 13a is 0, and the pack 7 is in a state in which it is tilted only in the front-rear direction. In this state, the strawberry 5(3) is placed at the right front corner position of the pack 7. This allows the strawberry 5(3) to be placed at the right front corner position so as to contact the right and front inner walls 7b of the pack 7. After that, the tilt control unit 49 maintains the pack 7 in a state in which the left-right tilt of the table 13a is set to zero and the pack 7 is tilted only in the front-rear direction. In this state, the fourth and subsequent strawberries 5 are placed one after another. In this way, twelve strawberries 5 are placed on the inclined placement surface 7a of the pack 7, packed from the bottom up.

[0051] Returning to Fig. 2, the robot controller 29 has a motion control unit 51 and a servo amplifier 53. Based on a position command received from the robot control unit 41 of the higher-level control device 27, the motion control unit 51 calculates target rotation angles and the like of the motors M1 to M6 of the robot 9 required to move the end point position of the arm 9a of the robot 9 (the position of the suction hand 31) to the position specified by the position command, and outputs motor position commands corresponding to the motors M1 to M6 based on the target rotation angles and detection values ​​and the like of the encoders E1 to E6 of the motors M1 to M6.

[0052] The servo amplifier 53 controls the drive power supplied to each of the motors M1 to M6 based on the motor position command input from the motion control unit 51, and controls the operation of the robot 9.

[0053] The above-mentioned processes in the class determination unit 33, weight estimation unit 35, storage planning unit 37, quality determination unit 39, robot control unit 41, weight measurement unit 43, weight determination unit 45, contact detection unit 47, tilt control unit 49, etc. of the upper control device 27 are not limited to the examples of division of the processes. For example, the processes may be performed by a smaller number of processing units (for example, one processing unit), or may be performed by a processing unit that is further divided. In addition, the functions of each of the above-mentioned processing units do not all need to be executed by the upper control device 27, and some or all of the functions may be executed by the robot controller 29. For example, the functions of the robot control unit 41 may be executed by either the upper control device 27 or the robot controller 29, or may be executed by both. When all of the functions of each of the above-mentioned processing units of the upper control device 27 are executed by the robot controller 29, the upper control device 27 may be omitted. The functions of each of the above processing units of the upper control device 27 may be implemented by a program executed by a CPU 901 (see FIG. 15) described later, or some or all of the functions may be implemented by actual devices such as ASICs, FPGAs, or other electrical circuits.

[0054] <3. Processing procedure of upper control device> 10 to 12, an example of the processing procedure (robot control method) executed by the upper controller 27 will be described. Note that the flowcharts shown in Fig. 10 to 12 are processing procedures for one tray 3, and it is assumed that the tray 3 containing strawberries 5 is carried into the robot system 1 before the flow is started, and that the emptied tray 3 is carried out from the robot system 1 after the flow is completed.

[0055] 10, in step S5, the host controller 27 causes the robot 9 to prepare for the container filling operation via the robot control unit 41. The preparation is, for example, setting new packs 7 and pack stands 8 on the movable placement table 13. Note that the preparation may be performed by a device other than the robot 9, or may be performed by a worker.

[0056] In step S100, the upper control device 27 executes a storage planning process for planning a storage state of the strawberries 5 in the packs 7. The storage planning process will be described later in detail (FIG. 11).

[0057] In step S10, the upper control device 27 determines whether the strawberries 5 to be transferred next should be taken out from the tray 3 or the temporary placement table 15, based on the storage state planned in the above step S100. If the upper control device 27 determines that the strawberries 5 should be taken out from the temporary placement table 15 (step S10: NO), the process proceeds to step S15.

[0058] In step S15, the host control device 27 causes the robot control unit 41 to move the suction hand 31 of the robot 9 to the top of the temporary placement table 15, and causes the robot 9 to hold the strawberries 5 to be transferred that are determined based on the storage state planned in step S100 among the strawberries 5 temporarily placed on the temporary placement table 15. Then, the process proceeds to step S65 described later.

[0059] On the other hand, in the above step S10, if the upper control device 27 determines that the strawberries 5 are to be removed from the tray 3 (step S10: YES), the process proceeds to step S20.

[0060] In step S20, the host controller 27 causes the robot control unit 41 to move the suction hand 31 to above the strawberry 5 to be transferred, which has been determined based on the storage state planned in step S100 among the strawberries 5 stored in the tray 3. The host controller 27 causes the quality determination unit 39 to determine whether the quality of the strawberry 5 to be transferred is good or bad, based on the image of the top surface of the strawberry 5 captured by the tray camera 21 or the robot camera 25.

[0061] In step S25, the host controller 27 causes the robot control unit 41 to hold the strawberry 5, which has been subjected to the quality inspection in step S20, by the suction hand 31 of the robot 9.

[0062] In step S30, the host controller 27 causes the weight measuring unit 43 to measure the actual weight of the strawberry 5 held by the robot 9 based on the measurements of the weighing scale 11 before and after the robot 9 holds the strawberry 5.

[0063] In step S35, the host controller 27 judges whether or not the robot 9 was able to hold the strawberry 5. As an example, if the actual weight of the strawberry 5 measured in the above step S30 is 0 or a value close to 0, the host controller 27 judges that the robot 9 was unable to hold the strawberry 5 (step S35: NO) and returns to the above-mentioned step S100. On the other hand, if the actual weight of the strawberry 5 is greater than a predetermined value, the host controller 27 judges that the robot 9 was able to hold the strawberry 5 (step S35: YES) and proceeds to step S40.

[0064] In step S40, the host controller 27 causes the robot control unit 41 to move the strawberry 5 held by the robot 9 to above the mirror 17. The host controller 27 causes the quality determination unit 39 to determine whether the quality of the strawberry 5 is good or bad, based on the images of the side and bottom of the strawberry 5 captured by the robot camera 25 through the mirror 17.

[0065] In step S45, the higher-level control device 27 determines whether or not the quality inspections in both steps S20 and S40 have been determined to be good, using the quality determination unit 39. If the quality inspections in either one or both of them have been determined to be bad (step S45: NO), the process proceeds to step S50.

[0066] In step S50, the host controller 27 causes the robot control unit 41 to move the strawberries 5 held by the robot 9 to the disposal box 19 for disposal. After that, the process returns to the above-mentioned step S100.

[0067] On the other hand, in the above step S45, if the quality inspections in both steps S20 and S40 determine that the product is good (step S45: YES), the process proceeds to step S55.

[0068] In step S55, the upper control device 27 causes the weight determination unit 45 to calculate the weight difference between the estimated weight calculated in step S100 (see step S130 in FIG. 11) and the actual weight calculated in step S30 for the strawberry 5 held by the robot 9 in step S25, and determines whether the weight difference is smaller than a predetermined threshold value. If the weight difference is larger than the predetermined threshold value (step S55: NO), the upper control device 27 proceeds to step S60.

[0069] In step S60, the host controller 27 causes the robot control unit 41 to move the strawberries 5 held by the robot 9 to the temporary placement table 15 and place them temporarily. At this time, the host controller 27 records information on the strawberries 5 temporarily placed on the temporary placement table 15, such as the grade, actual weight, and quality (good), in an appropriate memory unit (such as the recording device 917; see FIG. 15) of the host controller 27, for example, in association with the temporary placement location of the strawberries 5. Thereafter, the process returns to the above-mentioned step S100.

[0070] On the other hand, in step S55, if the weight difference is smaller than the predetermined threshold value (step S55: YES), the host controller 27 proceeds to step S65.

[0071] In step S65, the host controller 27 controls the robot control unit 41 to move the strawberries 5 held by the robot 9 to the pack 7 and place them on the inclined placement surface 7a from below.

[0072] In step S70, the upper control device 27 judges whether or not the packing of the strawberries 5 into the packs 7 has been completed based on the storage state planned in the above step S100. If the packing of the strawberries 5 into the packs 7 has not been completed (step S70: NO), the process returns to the above step S100. On the other hand, if the packing of the strawberries 5 into the packs 7 has been completed (step S70: YES), the process proceeds to step S75.

[0073] In step S75, the host controller 27 causes the robot 9 to carry out the packs 7 in which the strawberries 5 have been packed into containers, via the robot control unit 41. Note that the carrying out may be performed by a device other than the robot 9, or may be performed by an operator.

[0074] In step S80, the upper control device 27 judges whether the remaining amount of strawberries 5 on the tray 3 is less than the minimum number of strawberries 5 that can be accommodated in one pack 7 based on the image captured by the tray camera 21. The minimum number of strawberries 5 is the number of strawberries 5 in the storage mode that has the smallest number of strawberries 5 among the storage modes that can be planned by the storage planning unit 37. If the remaining amount of strawberries 5 on the tray 3 is equal to or greater than the minimum number of strawberries 5 that can be accommodated in one pack 7 (step S80: NO), the process returns to the above-mentioned step S5. On the other hand, if the remaining amount of strawberries 5 on the tray 3 is less than the minimum number of strawberries 5 that can be accommodated in one pack 7 (step S80: YES), the process proceeds to step S200.

[0075] In step S200, the upper controller 27 executes a remaining amount transfer process for transferring all the strawberries 5 remaining on the tray 3 to the temporary placement table 15. The remaining amount transfer process will be described in detail later (FIG. 12). Then, this flow chart ends.

[0076] FIG. 11 is a flowchart showing an example of the detailed contents of the accommodation planning process in step S100.

[0077] As shown in FIG. 11, in step S110, the host controller 27 acquires an image captured by the tray camera 21.

[0078] In step S120, the upper control device 27, through the grade determination unit 33, determines the grade of each strawberry 5 contained in the tray 3 based on the image captured by the tray camera 21 acquired in step S110 above and the grade criteria for the strawberries 5.

[0079] In step S130, the upper control device 27 calculates, via the weight estimation unit 35, an estimated weight for each strawberry 5 contained in the tray 3 based on the image captured by the tray camera 21 acquired in step S110 above.

[0080] In step S140, the upper control device 27 determines, based on the information recorded in the above-mentioned step S60, whether or not there are strawberries 5 temporarily placed on the temporary placement table 15. If there are strawberries 5 temporarily placed (step S140: YES), the process proceeds to step S150.

[0081] In step S150, the host controller 27 plans the storage mode by the storage planning unit 37 so that the strawberries 5 temporarily placed on the temporary placement table 15 are preferentially stored in the packs 7 over the strawberries 5 stored in the tray 3. At this time, the host controller 27 plans the storage mode based on the information recorded in the above-mentioned step S60. Then, the process returns to step S10 in FIG. 10.

[0082] On the other hand, in the above step S140, if there are no strawberries 5 temporarily placed on the temporary placement table 15 (step S140: NO), the process proceeds to step S160.

[0083] In step S160, the host controller 27 causes the storage planning unit 37 to plan the storage manner of the packs 7 based on the strawberries 5 stored in the tray 3. After that, the process returns to step S10 in FIG.

[0084] FIG. 12 is a flowchart showing an example of the details of the remaining amount transfer process in step S200.

[0085] As shown in FIG. 12, in step S210, the upper control device 27 has the grade determination unit 33 determine the grade of each strawberry 5 remaining on the tray 3 based on the image captured by the tray camera 21 and the grade criteria for the strawberries 5.

[0086] In step S220, the host controller 27 controls the robot control unit 41 to make the suction hand 31 of the robot 9 hold any one of the strawberries 5 remaining on the tray 3.

[0087] In step S230, the host controller 27 causes the weight measuring unit 43 to measure the actual weight of the strawberry 5 held by the robot 9 based on the measurements of the weighing scale 11 before and after the robot 9 holds the strawberry 5.

[0088] In step S240, the upper control device 27 judges whether or not the robot 9 was able to hold the strawberry 5. If the robot 9 was unable to hold the strawberry 5 (step S240: NO), the process returns to step S210. On the other hand, if the robot 9 was able to hold the strawberry 5 (step S240: YES), the process proceeds to step S250.

[0089] In step S250, the host controller 27 causes the robot control unit 41 to move the strawberry 5 held by the robot 9 to above the mirror 17. The host controller 27 causes the quality determination unit 39 to determine whether the quality of the strawberry 5 is good or bad, based on the images of the side and bottom of the strawberry 5 captured by the robot camera 25 through the mirror 17.

[0090] In step S260, the higher-level controller 27 determines whether or not the quality inspection in step S250 has determined the quality to be good by the quality determination unit 39. If the quality inspection has determined the quality to be bad (step S260: NO), the process proceeds to step S270.

[0091] In step S270, the host controller 27 causes the robot control unit 41 to move the strawberries 5 held by the robot 9 to the disposal box 19 for disposal. Then, the process returns to step S210.

[0092] On the other hand, in the above step S260, if the quality inspection in step S250 determines that the product is good (step S260: YES), the process proceeds to step S280.

[0093] In step S280, the host controller 27 causes the robot control unit 41 to move and temporarily place the strawberries 5 held by the robot 9 on the temporary placement table 15. At this time, the host controller 27 records information on the grade, actual weight, quality (good), etc. of the strawberries 5 temporarily placed on the temporary placement table 15 in an appropriate memory unit (e.g., the recording device 917, etc.; see FIG. 15 ) of the host controller 27, for example, in association with the temporary placement location of the strawberries 5.

[0094] In step S290, the host controller 27 determines whether the tray 3 is empty or not based on the image captured by the tray camera 21. If the tray 3 is not empty (step S290: NO), the process returns to step S210. On the other hand, if the tray 3 is empty (step S290: YES), the process returns to FIG. 10 and ends the flow chart.

[0095] The above-described processing procedure is an example, and at least some of the above procedures may be deleted or changed, or procedures other than those described above may be added. Furthermore, the order of at least some of the above procedures may be changed, or multiple procedures may be combined into a single procedure. For example, step S20 in FIG. 10 may be omitted. In that case, in step S45, it is sufficient to judge only the result of the quality inspection in step S40.

[0096] <4. Effects of the embodiment> As described above, in the robot system 1 of the embodiment, the pack 7 to which the strawberries 5 stored in the tray 3 are transferred is placed on the movable placement table 13 that is inclined at least in the front-rear direction with respect to the horizontal plane. The robot control unit 41 of the upper control device 27 controls the robot 9 so that the strawberries 5 held by the robot 9 are packed from the bottom onto the inclined placement surface 7a of the pack 7. By packing the strawberries 5 from the bottom onto the inclined placement surface 7a of the pack 7, the strawberries 5 can be stored in a stable state without gaps even if the placement surface 7a of the pack 7 is flat. Therefore, a general-purpose container capable of storing a wide variety of objects can be used as the pack 7. Therefore, compared to using a dedicated container with unevenness formed according to the type, size, shape, etc. of the object, the installation space and cost of the pack 7 can be reduced. Therefore, the object can be stably packed into a general-purpose container.

[0097] In the embodiment, the tilt control unit 49 of the host controller 27 may control the tilt of the movable placement table 13 so as to change the left-right tilt angle according to the placement position when the strawberries 5 held by the robot 9 are placed on the placement surface 7a of the pack 7. In this case, it becomes possible to actively adjust the left-right tilt of the placement surface 7a according to the state of the strawberries 5 placed on the placement surface 7a of the pack 7. As a result, even if the placement surface 7a is flat, the placed strawberries 5 are less likely to roll, and can be stored in a more stable state.

[0098] In the embodiment, the contact detection unit 47 of the upper control device 27 may detect contact between the strawberry 5 held by the robot 9 and another object, and the robot control unit 41 may switch the control for placing the strawberry 5 from position control to force control at the timing when the contact is detected by the contact detection unit 47. In this case, the strawberry 5 can be gently placed in the pack 7, and even if the object is soft like a strawberry, it can be packed into the container without any gaps and without being damaged.

[0099] In an embodiment, the quality determination unit 39 and the weight determination unit 45 of the host controller 27 may determine whether the strawberries 5 held by the robot 9 meet a predetermined standard, and the robot control unit 41 may control the robot 9 to transfer the strawberries 5 to a location other than the tray 3 and the pack 7 when it is determined that the strawberries 5 do not meet the predetermined standard. In this case, it is possible to prevent the strawberries 5 that do not meet the predetermined standard from being packed into the pack 7.

[0100] In the robot system 1 of the embodiment, the tray camera 21 detects the state of the strawberries 5 stored in the tray 3, and the weight estimation unit 35 of the upper control device 27 calculates an estimated weight for each strawberry 5 based on the detection state of the strawberries 5 by the tray camera 21. In this case, if there is a large difference between the estimated weight and the actual weight, there is a possibility that the total weight of the packs 7 after storage is completed will not fall within the specified weight range.

[0101] Therefore, the weight measuring unit 43 may measure the actual weight of the strawberries 5 held by the robot 9, and when the weight determining unit 45 determines that the difference between the estimated weight and the actual weight is greater than a threshold value, the robot control unit 41 may control the robot 9 to transfer the strawberries 5 to a location other than the tray 3 and the pack 7. In this case, the strawberries 5 can be packed into containers so that the total weight of the pack 7 falls within a specified weight range. In addition, by transferring the strawberries 5 with a large difference between the estimated weight and the actual weight to another location without returning them to the tray 3, the strawberries 5 for which weight estimation and weight measurement have not been completed can be distinguished from the strawberries 5 for which weight estimation and weight measurement have been completed. This makes it possible to avoid duplicate weight estimation and weight measurement, thereby improving the efficiency of the container packing work.

[0102] In the embodiment, the robot control unit 41 may control the robot 9 to transfer the strawberries 5 to the temporary placement table 15 when the weight determination unit 45 determines that the difference between the estimated weight and the actual weight is greater than a predetermined threshold value. In this case, the strawberries 5 whose difference between the estimated weight and the actual weight is greater than the threshold value can be temporarily placed without being packed in a container. This makes it possible to pack the strawberries 5 whose difference between the estimated weight and the actual weight is large into other packs 7 without discarding them, thereby reducing waste.

[0103] In an embodiment, the tray camera 21 may detect the state of the strawberries 5 stored in the tray 3, the robot camera 25 may detect the state of the strawberries 5 held by the robot 9, and the quality determination unit 39 may determine the quality of the strawberries 5 based on the detection state of the strawberries 5 by at least one of the tray camera 21 and the robot camera 25. In that case, the robot control unit 41 may control the robot 9 to transfer the strawberries 5 to a location other than the tray 3 and the pack 7 when the quality determination unit 39 determines that the strawberries 5 are of poor quality. In this case, it is possible to prevent poor-quality strawberries 5 from being packed into the pack 7.

[0104] In an embodiment, the robot control unit 41 may control the robot 9 to transfer the strawberries 5 to the temporary placement table 15 when the weight determination unit 45 determines that the difference between the estimated weight and the actual weight is greater than the threshold value and the quality determination unit 39 determines that the quality of the strawberries 5 is good. In this case, since it is known that there is no problem with the quality of the temporarily placed strawberries 5, the temporarily placed strawberries 5 can be immediately transferred to the packs 7 without quality determination when they are packed into the next packs 7. This makes it possible to avoid duplicate quality determinations, thereby improving the efficiency of the packing work.

[0105] In the embodiment, the robot control unit 41 may control the robot 9 to hold the strawberries 5 temporarily placed on the temporary placement table 15 with priority over the strawberries 5 contained in the tray 3. In this case, the number of strawberries 5 temporarily placed on the temporary placement table 15 can be reduced, and the installation space of the temporary placement table 15 can be reduced. Also, it is possible to avoid a situation where the number of strawberries 5 on the temporary placement table 15 becomes too large, making it impossible to temporarily place new strawberries 5 thereon.

[0106] In an embodiment, the storage planning unit 37 of the host control device 27 may plan the storage state of the strawberries 5 in the packs 7 based on the detection state of the strawberries 5 by the tray camera 21, and the robot control unit 41 may control the robot 9 to transfer the strawberries 5 based on the planned storage state. In this case, it is possible to eliminate the trouble of the user planning the storage state in the packs 7 based on the strawberries 5 stored in the trays 3 and inputting the planned storage state, thereby saving labor and improving user convenience.

[0107] In an embodiment, the storage planner 37 may plan the storage state so that the total weight of the packs 7 after storing the strawberries 5 falls within a predetermined range of specified weight. In this case, the user can be saved from the trouble of selecting the strawberries 5 in advance so that the weight falls within the specified weight range and planning the storage state of the packs 7, thereby saving labor and improving user convenience.

[0108] In an embodiment, the grade determination unit 33 of the higher-level control device 27 may determine the grade of each strawberry 5 based on the detection state of the strawberries 5 by the tray camera 21 and the grade criteria, and the storage planning unit 37 may plan the storage mode so that strawberries 5 of a common grade are stored in each pack 7. In this case, even if strawberries 5 of different grades are mixed and stored in the tray 3, the strawberries 5 can be classified and packaged in packs 7 according to their grades.

[0109] In the embodiment, the storage planning unit 37 may plan the storage mode such that, when there are strawberries 5 temporarily placed on the temporary placement table 15, the strawberries 5 temporarily placed on the temporary placement table 15 are preferentially stored in the pack 7 over the strawberries 5 stored in the tray 3. In this case, the number of strawberries 5 temporarily placed on the temporary placement table 15 can be reduced, and the installation space for the temporary placement table 15 can be reduced. Also, it is possible to avoid a situation in which the number of strawberries 5 on the temporary placement table 15 increases too much, making it impossible to temporarily place new strawberries 5 thereon.

[0110] <5. Modifications> The disclosed embodiments are not limited to those described above, and various modifications are possible without departing from the spirit and technical concept thereof.

[0111] For example, a detector capable of detecting the posture of the strawberry 5 held by the robot 9 may be provided at an appropriate location in the robot system 1. As an example, the posture includes roll (rotation around a front-to-back axis relative to the direction of movement of the strawberry 5), pitch (rotation around a left-to-right axis relative to the direction of movement of the strawberry 5), yaw (rotation around an up-to-down axis relative to the direction of movement of the strawberry 5), etc. The detector is, for example, a camera. In this case, the robot control unit 41 can adjust the posture of the strawberry 5 according to the detected posture before placing it in the pack 7, so that the strawberries 5 can be stored in a more stable state.

[0112] The above modification will be described in detail with reference to Fig. 13 and Fig. 14. Fig. 13 is a diagram showing an example of a configuration of a robot system 1A according to the above modification, and Fig. 14 is a flowchart showing an example of a processing procedure executed by the upper control device 27 in the above modification.

[0113] As described above, the strawberries 5 are stored in the tray 3 in a position where, for example, the tip side opposite the stalk faces upward, and the robot 9 holds and transports the strawberries 5 and places them in the pack 7 in a proper position. However, the position of the strawberries 5 in the tray 3 may not be uniform, and when the number of strawberries 5 in the tray 3 decreases, the position may change due to rolling or the like. Therefore, the tray 3 may contain not only strawberries 5 in a position where the tip side opposite the stalk faces upward, but also strawberries 5 in a position where the stalk faces upward and strawberries 5 in a position where the stalk faces sideways. If such strawberries 5 are placed in the pack 7 in this position, they will be packed in a container in an incorrect position.

[0114] Therefore, as shown in FIG. 13, the robot system 1A has a posture detection camera 55 in addition to the configuration of the robot system 1 according to the embodiment described above. The posture detection camera 55 (an example of a second detector) is arranged, for example, to the side or diagonally above the pack 7, and before the robot 9 places the strawberry 5 on the pack 7, it captures an image of the strawberry 5 held by the robot 9 to detect the posture of the strawberry 5. The posture detection camera 55 may be a 2D camera or a 3D camera, but a 3D camera capable of acquiring information in the depth direction is preferable. The posture detection camera 55 may be arranged anywhere as long as it can detect the posture of the strawberry 5 (for example, built into the body part of the robot 9). The posture detection camera 55 may be a sensor other than a camera as long as it can detect the posture of the strawberry 5. The image captured by the posture detection camera 55 is transmitted to the upper control device 27. The upper control device 27 determines whether the posture of the strawberry 5 is appropriate based on the received image. The proper posture is a posture that is determined in advance when packing the strawberries 5 into the packs 7, and is, for example, a posture in which the tip side opposite the stem of the strawberries 5 faces upward. Note that, for example, when the strawberries 5 are packed into the packs 7 with their stems facing upward, this posture may be determined as the proper posture.

[0115] The robot control unit 41 of the upper control device 27 controls the robot 9 to adjust the posture of the strawberry 5 based on the posture of the strawberry 5 detected by the posture detection camera 55. As an example, when the posture of the strawberry 5 detected by the posture detection camera 55 is a posture in which the stalk faces upward or the stalk faces sideways, the robot control unit 41 operates each joint of the arm 9a to change the posture of the strawberry 5 held by the suction hand 31 to a posture in which the tip side opposite the stalk faces upward, and places the strawberry 5 in the changed posture on the pack 7. Note that, when the posture of the strawberry 5 detected by the posture detection camera 55 is a posture in which the tip side opposite the stalk faces upward, the robot control unit 41 places the strawberry 5 in the pack 7 without changing the posture.

[0116] The configuration of the robot system 1A other than the above is similar to that of the robot system 1 according to the above embodiment, and therefore a description thereof will be omitted.

[0117] Fig. 14 shows an example of a processing procedure executed by the upper controller 27 in this modified example. The flowchart shown in Fig. 14 differs from the flowchart shown in Fig. 10 in that steps S61 and S63 are newly added.

[0118] Steps S5 to S60 are the same as those in Fig. 10, and therefore will not be described. In step S55, if the weight difference is smaller than the predetermined threshold value (step S55: YES), the upper controller 27 proceeds to the next step S61.

[0119] In step S61, the host controller 27 moves the strawberry 5 held by the robot 9 to or passes through the imaging position for the posture detection camera 55, and determines whether or not the posture of the strawberry 5 held by the robot 9 is correct based on the image received from the posture detection camera 55. If the host controller 27 determines that the posture is correct (step S61: YES), it proceeds to step S65 described below. On the other hand, if the host controller 27 determines that the posture is not correct (step S61: NO), it proceeds to the next step S63.

[0120] In step S63, the host controller 27 controls the robot 9 via the robot control unit 41 so as to change the strawberry 5 to an appropriate posture.

[0121] In step S65, the upper control device 27 causes the robot control unit 41 to move the strawberries 5 held by the robot 9 to the pack 7 and place them on the inclined placement surface 7a from the bottom. As a result, the strawberries 5 are placed in the pack 7 in the same posture if the posture is determined to be appropriate in the above step S61, and in the posture changed in the above step S63 if the posture is determined to be inappropriate in the above step S61. Note that, although steps S61 and S63 have been described as being performed between steps S55 and S65, this is not the only option. For example, the location where steps S61 and S63 are performed may be appropriately determined, such as between steps S35 and S40, or between steps S40 and S45.

[0122] Steps S70 and after are the same as those in FIG. 10 described above, and therefore the description will be omitted.

[0123] According to the modified example described above, the posture of the strawberries 5 can be adjusted according to the detected posture before being placed in the pack 7, so that the strawberries 5 can be stored in the pack 7 in a more stable state and the quality of the containerized packs 7 can be improved.

[0124] Although the above describes a case where camera 55 for posture detection is newly provided, for example, the posture of strawberry 5 held by robot 9 may be detected by pack camera 23 (an example of a detector). In this case, a drive device capable of changing the position and orientation of pack camera 23 may be provided as necessary, and the position and orientation of pack camera 23 may be changed when imaging pack 7 and when imaging the posture of strawberry 5. Robot control unit 41 of host control device 27 controls robot 9 to adjust the posture of strawberry 5 based on the posture of strawberry 5 detected by pack camera 23. In this modified example, pack camera 23 can also be used as a camera for detecting the posture of strawberry 5.

[0125] In the embodiment, the tilt control unit 49 of the host controller 27 controls the tilt of the movable placement platform 13 so as to change the tilt angle in the left-right direction according to the placement position when the strawberries 5 held by the robot 9 are placed on the placement surface 7a of the pack 7, but the tilt angle in the front-back direction may be changed in addition to or instead of the left-right direction. In this case, the tilt in the front-back direction can also be actively adjusted according to the state of the strawberries 5 placed on the placement surface 7a of the pack 7, so that the strawberries 5 can be stored in a more stable state.

[0126] In the embodiment, a case where a plurality of strawberries 5 are stored in the tray 3 has been described, but the robot system 1 does not necessarily have to have a tray 3. For example, a plurality of strawberries 5 may simply be arranged without being stored in a container, or may be arranged on a transport device such as a conveyor.

[0127] In the embodiment, the robot system 1 has the temporary stand 15, but the various effects described in the above embodiment may be achieved even if the temporary stand 15 is not present. Therefore, it goes without saying that the scope of the right also includes a case where the robot system 1 does not have the temporary stand 15, depending on the effect to be obtained. Furthermore, in the embodiment, the robot camera 25 is installed on the robot 9, but similarly, the various effects described in the above embodiment may be achieved even if the robot camera 25 is not present. Therefore, it goes without saying that the scope of the right also includes a case where the robot camera 25 is not installed on the robot 9, depending on the effect to be obtained.

[0128] Furthermore, in the embodiment, the case where the robot system 1 has the movable placement table 13 has been described, but depending on the effect to be obtained, the robot system 1 may not have the movable placement table 13. In this case, the pack 7 may be placed on a horizontal table. For example, the robot 9 may be controlled so that the strawberries 5 that do not conform to the storage mode plan are temporarily placed on the temporary placement table 15, and the strawberries 5 that conform to the storage mode plan are held in the tray 3 based on the plan, and are placed on the pack 7 via an inspection position (above the mirror 17) for quality judgment by the quality judgment unit 39. This allows the series of flows of the robot system 1 to be fully automated.

[0129] <6. Example of hardware configuration for host control device> An example of the hardware configuration of the upper level control device 27 will be described with reference to FIG.

[0130] 15, the upper control device 27 includes, for example, a CPU 901, a ROM 903, a RAM 905, a dedicated integrated circuit 907 constructed for a specific application such as an ASIC or an FPGA, an input device 913, an output device 915, a recording device 917, a drive 919, a connection port 921, and a communication device 923. These components are connected to each other via a bus 909 and an input / output interface 911 so as to be able to transmit signals to each other.

[0131] The program can be recorded in, for example, the ROM 903, the RAM 905, or the recording device 917 such as a hard disk.

[0132] The program may be temporarily or non-temporarily (permanently) recorded on a removable recording medium 925 such as a magnetic disk such as a flexible disk, an optical disk such as various CD / MO disks / DVDs, or a semiconductor memory. Such a recording medium 925 may be provided as a so-called package software. In this case, the program recorded on the recording medium 925 may be read by the drive 919 and recorded on the recording device 917 via the input / output interface 911, the bus 909, etc.

[0133] The program may be recorded, for example, on a download site, another computer, another recording device, or the like (not shown). In this case, the program is transferred via a network NW such as a LAN or the Internet, and the communication device 923 receives the program. The program received by the communication device 923 may then be recorded in the recording device 917 via the input / output interface 911, the bus 909, or the like.

[0134] The program may be recorded in, for example, an appropriate external connection device 927. In this case, the program may be transferred via an appropriate connection port 921 and recorded in the recording device 917 via the input / output interface 911, the bus 909, etc.

[0135] The CPU 901 executes various processes according to the programs recorded in the recording device 917, thereby realizing processes by the above-mentioned class determination unit 33, weight estimation unit 35, storage planning unit 37, quality determination unit 39, robot control unit 41, weight measurement unit 43, weight determination unit 45, contact detection unit 47, tilt control unit 49, etc. The CPU 901 may, for example, directly read out and execute the programs from the recording device 917, or may execute the programs after loading them once into the RAM 905. When the CPU 901 receives a program via the communication device 923, the drive 919, or the connection port 921, for example, the CPU 901 may directly execute the received program without recording it in the recording device 917.

[0136] The CPU 901 may perform various processes as necessary based on signals and information input from an input device 913 such as a mouse, keyboard, and microphone (not shown).

[0137] The CPU 901 may output the results of the above-mentioned processing from an output device 915, such as a display device or an audio output device. The CPU 901 may transmit the processing results via a communication device 923 or a connection port 921, as necessary. The CPU 901 may record the processing results in the recording device 917 or recording medium 925.

[0138] In the above description, when "vertical", "parallel", "plane" and the like are used, the meanings are not strict. The terms "vertical", "parallel" and "plane" mean "substantially vertical", "substantially parallel" and "substantially plane" with allowance for design and manufacturing tolerances and errors.

[0139] In the above description, when the external dimensions, size, shape, position, etc. are described as "same", "equal", "different", etc., these descriptions are not intended to be strict. The terms "same", "equal", and "different" mean "substantially the same", "substantially the same", "substantially equal", and "substantially different", allowing for design and manufacturing tolerances and errors.

[0140] For example, when there is a description of a threshold value (see the flowchart in FIG. 10, etc.), a reference value, or other value that serves as a specific judgment criterion or a dividing line, the terms "same," "equal," "different," etc., used in relation to such a value have a strict meaning, unlike the above.

[0141] In addition to the above, the methods according to the above-mentioned embodiments and each modified example may be appropriately combined and used. Although not illustrated individually, the above-mentioned embodiments and each modified example may be implemented with various modifications without departing from the spirit thereof.

[0142] The problems and effects that the above-described embodiments and modifications are intended to solve are not limited to those described above. The embodiments and modifications may solve problems or achieve effects that are not described above, or may solve only some of the problems or achieve only some of the effects that are described. [Explanation of symbols]

[0143] 1. Robot System 1A Robot System 3 Tray (an example of the first container) 5. Strawberries (example of target object) 7 pack (example of second container) 7a Placement surface 7b Inner wall 8 pack stand 9. Robot 9a Arm 10 Force Sensor 11 Weight scale 13 Movable placement table (an example of a placement section) 15 Temporary placement table (an example of a temporary placement section) 17 mirror 19 Waste Box 21 Tray camera (an example of a detector) 23 Puck camera (an example of a detector) 25 Robot camera (an example of a state detection unit) 27 Upper control device 29 Robot Controller 31 Suction Hand 33 Grade Judgment Department 35 Weight estimation section 37 Containment Planning Department 39 Quality judgment unit (an example of a judgment unit) 41 Robot control unit 43 Weight measurement section 45 Weight determination unit (an example of a determination unit) 47 Contact detection unit 49 Tilt control section 51 Motion control section 53 Servo amplifier 55 Attitude detection camera (an example of the second detector)

Claims

1. a robot that transfers an object contained in a first container to a second container; a placement portion on which the second container is placed and which is inclined in at least a first direction with respect to a horizontal plane; a detector for detecting information regarding the first container and the second container; a robot control unit that controls the robot so as to place the object held by the robot on the inclined placement surface of the second container from below; A robot system having the above configuration.

2. a tilt control unit that controls the tilt of the placement unit so as to change a tilt angle in a second direction different from the first direction depending on a placement position when the object held by the robot is placed on the placement surface of the second container, The robot system of claim 1 .

3. a contact detection unit that detects contact between the object held by the robot and another object when the robot places the object on the placement surface of the second container, The robot control unit and switching control of placing the object from position control to force control at a timing when the contact is detected by the contact detection unit. The robot system of claim 1 .

4. a determination unit that determines whether the object held by the robot satisfies a predetermined criterion; The robot control unit includes: When the determination unit determines that the object does not satisfy the predetermined criterion, the robot is controlled to transfer the object to a location other than the first container and the second container. The robot system of claim 1 .

5. The detector comprises: Detecting a state of the object contained in the first container; The robot system includes: a weight estimation unit that calculates an estimated weight for each of the objects based on a detection state of the object by the detector; a weight measuring unit that measures an actual weight of the object held by the robot; a weight determination unit that determines whether a difference between the estimated weight and the actual weight of the object is greater than a predetermined threshold value; The robot control unit includes: When the weight determination unit determines that the difference is greater than the predetermined threshold value, the robot is controlled to transfer the object to a location other than the first container and the second container. The robot system according to claim 4 .

6. The apparatus further includes a temporary placement section on which the object is temporarily placed, The robot control unit includes: When the weight determination unit determines that the difference is greater than the predetermined threshold value, the robot is controlled to transfer the object to the temporary placement unit. The robot system according to claim 5 .

7. The detector comprises: Detecting a state of the object contained in the first container; The robot system includes: a state detection unit that detects a state of the object held by the robot; a quality determination unit that determines a quality of the object based on a detection state of the object by at least one of the detector and the state detection unit, The robot control unit includes: When the quality determination unit determines that the object is of poor quality, the robot is controlled to transfer the object to a location other than the first container and the second container. The robot system according to claim 4 .

8. The robot system includes: a weight estimation unit that calculates an estimated weight for each of the objects based on a detection state of the object by the detector; a weight measuring unit that measures an actual weight of the object held by the robot; a weight determination unit that determines whether a difference between the estimated weight and the actual weight of the object is greater than a predetermined threshold value; a temporary placement section on which the object is temporarily placed; and The robot control unit includes: When the weight determination unit determines that the difference is greater than the predetermined threshold value and the quality determination unit determines that the quality of the object is good, the robot is controlled to transfer the object to the temporary placement unit. The robot system according to claim 7.

9. The robot control unit includes: controlling the robot so as to hold the object temporarily placed on the temporary placement unit with priority over the object contained in the first container; The robot system according to claim 8.

10. The detector comprises: Detecting a state of the object contained in the first container; The robot system includes: The method further includes a storage planning unit that plans a storage mode of the object in the second container based on a detection state of the object by the detector, The robot control unit includes: controlling the robot so that the robot transfers the object based on the storage mode plan; The robot system according to any one of claims 1 to 4.

11. The accommodation planning unit includes: The storage mode is planned so that a total weight of the second container after storing the object is within a predetermined range of a specified weight. The robot system of claim 10.

12. The robot system includes: The apparatus further includes a class determining unit that determines a class for each of the objects based on a detection state of the object in the detector and a predetermined criterion related to a state of the object, The accommodation planning unit includes: The storage mode is planned so that each of the second containers stores the object of the same class. The robot system of claim 10.

13. The robot system includes: The apparatus further includes a temporary placement section on which the object is temporarily placed, The accommodation planning unit includes: When the object is temporarily placed on the temporary placement section, the storage mode is planned so that the object temporarily placed on the temporary placement section is preferentially stored in the second container over the object stored in the first container. The robot system of claim 10.

14. a second detector for detecting a posture of the object held by the robot; The robot control unit includes: controlling the robot to adjust the posture of the object based on the posture of the object detected by the second detector; The robot system according to any one of claims 1 to 3.

15. The detector comprises: Detecting the posture of the object held by the robot; The robot control unit includes: controlling the robot so as to adjust the posture of the object based on the posture of the object detected by the detector; The robot system according to any one of claims 1 to 3.

16. a robot that transfers an object contained in a first container to a second container; a detector for detecting information regarding the first container and the second container; a storage planning unit that plans a storage state of the object in the second container based on a detection state of the object stored in the first container detected by the detector; a state detection unit that detects a state of the object held by the robot; a quality determination unit that determines a quality of the object based on a detection state of the object by at least one of the detector and the state detection unit; a temporary placement section on which the object not conforming to the storage mode plan is temporarily placed; a robot control unit that controls the robot so that the object contained in the first container is held, the quality is determined in the quality determination unit, and the object is placed in the second container based on the plan of the storage mode; A robot system having the above configuration.

17. The second container is placed on a placement portion inclined relative to a horizontal plane. The robotic system of claim 16.

18. A robot control method for controlling a robot that transfers an object contained in a first container to a second container, comprising: controlling the robot so as to place the object held by the robot from below on an inclined placement surface of the second container, the second container being placed on a placement part that is inclined in at least a first direction with respect to a horizontal plane, based on information regarding the first container and the second container detected by a detector; A robot control method comprising the steps of:

19. a robot that transfers an object contained in a first container to a second container; a detector for detecting information regarding the first container and the second container; a storage planning unit that plans a storage state of the object in the second container based on a detection state of the object stored in the first container detected by the detector; a state detection unit that detects a state of the object held by the robot; a quality determination unit that determines a quality of the object based on a detection state of the object by at least one of the detector and the state detection unit; A robot control method for controlling a robot in a robot system comprising: controlling the robot to temporarily place the object that does not conform to the plan of the storage mode on a temporary placement unit, and to hold the object stored in the first container based on the plan of the storage mode, through a process of determining the quality in the quality determination unit, and then to place the object in the second container; A robot control method comprising the steps of:

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