Object operating device, articulated robotic arm, and moving robot

Abstract

To provide an object operating device that can perform object operation in a position apart from a substrate in a depth direction and the like.SOLUTION: An object operating device includes: a substrate 51; a first linear motion body linearly moving along a first axis relative to the substrate; and a second linear motion body linearly moving along a second axis parallel to the first axis relative to the first linear motion body and including an end effector for operating an object, where the first linear motion body and the second linear motion body are drive independently to each other.SELECTED DRAWING: Figure 2

Description

[Technical field]

[0001] The present invention relates to an object manipulation device, and more particularly to an object manipulation device that can be mounted on a mobile manipulator or the like. [Background technology]

[0002] In recent years, transport robots (or mobile manipulators) have been used for automating warehouses (for example, Patent Documents 1 and 2). As an example, this type of transport robot performs a process of acquiring (picking) an object placed on a shelf or a table in a warehouse, moving within the warehouse, and placing (placing) the object in another location. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2015-178141 A [Patent Document 2] JP 2019-048375 A Summary of the Invention [Problem to be solved by the invention]

[0004] However, in this type of conventional device, object manipulation at a position distant from the base in the depth direction, etc., was not anticipated or not sufficiently considered, making it difficult to manipulate an object at a deep position on the shelf or table in the depth direction using the conventional device.

[0005] The present invention has been made in view of the above-mentioned technical background, and has an object to perform object manipulation at a position separated from a base body in the depth direction or the like. [Means for solving the problem]

[0006] The above-mentioned technical problems can be solved by an object manipulation device, a multi-joint robot arm, a mobile robot, or the like having the following configuration.

[0007] In other words, the object manipulation device of the present invention comprises a base, a first linear body that moves linearly along a first axis relative to the base, and a second linear body that moves linearly along a second axis parallel to the first axis relative to the first linear body and has an end effector that manipulates an object, and the first linear body and the second linear body are driven independently.

[0008] With this configuration, the end effector can be freely linearly displaced by the independently driven multi-stage linear bodies, making it possible to manipulate objects at positions far from the base in the depth direction. For example, with the base placed in front of the shelf, it is possible to approach an object located deep on the shelf in the depth direction. Effect of the Invention

[0009] According to the present invention, it is possible to perform object manipulation at a position separated from the base body in the depth direction or the like. [Brief description of the drawings]

[0010] [Figure 1] FIG. 1 is a perspective view showing the overall configuration of a mobile manipulator. [Diagram 2] FIG. 2 is an enlarged perspective view of the external appearance of the object manipulation unit. [Diagram 3] FIG. 3 is an explanatory diagram showing an example of gripping an object by a gripper. [Figure 4] FIG. 4 is a conceptual plan view of a gripper in which the left and right claws are independently driven. [Diagram 5] FIG. 5 is a functional block diagram of the mobile manipulator. [Figure 6] FIG. 6 is a flowchart for picking up an object on a shelf by a mobile manipulator. [Figure 7]FIG. 7 is a conceptual diagram showing how the first camera recognizes the marker. [Figure 8] FIG. 8 is a conceptual diagram showing how the second camera recognizes the code. [Figure 9] FIG. 9 is a conceptual diagram showing an example of a series of operations related to picking. [Figure 10] FIG. 10 is a conceptual diagram of a case where a pre-operation process is performed on a group of objects formed by piling up objects. [Figure 11] FIG. 11 is a conceptual diagram showing an example of an operation when picking an object from a group of objects formed by piling up objects. [Figure 12] FIG. 12 is a flowchart regarding placing of an object at a deep position on a shelf board in the depth direction by the mobile manipulator. [Figure 13] FIG. 13 is an explanatory diagram showing an example of a pre-placing operation on a shelf board. [Figure 14] FIG. 14 is an explanatory diagram showing an example of a series of operations when a plurality of objects are pre-placed on a shelf board and then actual placement is performed. [Figure 15] FIG. 15 is an explanatory diagram showing another example of the operation of placing an object on an object. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0011] Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings.

[0012] 1. First Embodiment As a first embodiment, an example in which the present invention is applied to a mobile robot that manipulates and transports objects, that is, a mobile manipulator 100, will be described.

[0013] (1.1 Configuration of the mobile manipulator) 1 is an external perspective view showing the overall configuration of a mobile manipulator 100 according to this embodiment. A coordinate system consisting of three mutually orthogonal axes (x-axis, y-axis, and z-axis) is displayed in the lower left of the figure, and hereinafter, the positive direction of the x-axis may be referred to as the forward direction, the negative direction as the backward direction, the positive direction of the y-axis as the leftward direction, the negative direction as the rightward direction, the positive direction of the z-axis as the upward direction, and the negative direction as the downward direction.

[0014] As is clear from the figure, the mobile manipulator 100 includes a main body 10 having an overall shape of a substantially rectangular parallelepiped with long sides in the vertical direction, a multi-joint robot arm unit 30 attached to the front end of the upper end of the main body 10, and an object manipulation unit 50 attached to the tip of the multi-joint robot arm unit 30. The left and right side surfaces of the main body 10 are parallel to the x-axis (xz plane), and the front and back surfaces are parallel to the y-axis (yz plane). In this embodiment, the multi-joint robot arm unit 30 and the object manipulation unit 50 are referred to separately, but they may be collectively referred to simply as a multi-joint robot arm.

[0015] As is clear from the figure, in this embodiment, the articulated robot arm unit 30 is disposed on the center line of the left-right width of the main body unit.

[0016] This configuration provides a good left-right weight balance for the mobile manipulator 100. Also, the left-right width of the mobile manipulator can be made smaller than when, for example, the articulated robot arm unit 30 is attached to the side surface.

[0017] On the front surface of the main body 10, object storage sections 15 each having seven rectangular parallelepiped spaces for storing objects are aligned vertically with their openings facing forward. Each space of the object storage section 15 has a size large enough to store at least one object.

[0018] According to this configuration, since the object storage unit 15 has multiple storage spaces, multiple objects can be transported simultaneously. In addition, since the spaces for storing objects are arranged vertically, the width of the mobile manipulator 100 can be reduced. This enables movement through narrow passages, etc.

[0019] The articulated robot arm unit 30 is attached above (vertically above) the object accommodation unit 15.

[0020] According to this configuration, the articulated robot arm unit 30 can be used to access the object storage unit 15 from above.

[0021] A LiDAR device 13 is installed on the top surface of the main body 10 at a position higher than the main body 10 via an upside-down U-shaped rod-like support member 12. The LiDAR device 13 is, for example, a LiDAR unit, and can detect the distance, position, shape, etc. of an object.

[0022] According to such a configuration, sensing can be performed from a high position using the LiDAR device 13. As a result, even if there is a shelf or the like in the vicinity, self-location estimation can be performed more reliably.

[0023] The bottom surface of the main body 10 is provided with a moving mechanism 20 consisting of two wheels (W1, W2) that are controlled and driven independently on the left and right sides. In addition, passive wheels W' that rotate passively are arranged at the four corners of the bottom surface.

[0024] According to this configuration, a low-cost movement mechanism can be realized by utilizing the differential two wheels.

[0025] In this embodiment, the articulated robot arm unit 30 has four rotationally driven joints (J1 to J4). One end (or base end) of a rod-shaped first link 31 is swingably connected to the upper and front end of the main body unit 10 via the first joint (J1). At this time, the central axis of rotation of the first joint (J1) is a horizontal axis (or pitch axis) extending in the left-right direction.

[0026] One end (or base end) of the rod-shaped second link 32 is swingably connected to the other end (or tip) of the first link 31 via a second joint (J2). At this time, the rotation center axis of the second joint (J2) is a horizontal axis (or pitch axis) extending in the left-right direction.

[0027] One end (base end) of the third link 33, which is bent shorter than the first link 31 and the second link 32, is swingably connected to the other end (or tip) of the second link 32 via a third joint (J3). At this time, the rotation center axis of the third joint (J3) is a horizontal axis (or pitch axis) extending in the left-right direction.

[0028] According to such a configuration, the hand position of the third link 33 can be freely positioned on a plane (xz plane) parallel to the side surface of the main body unit 10. This increases the degree of freedom in the positioning of the object manipulation unit 50.

[0029] The object manipulator 50 is rotatably attached via a fourth joint (J4) to the tip of the third link 33. The rotation center axis of the fourth joint (J4) is parallel to the normal to the top surface of the object manipulator 50, and is parallel to the vertical axis in the example shown in the figure.

[0030] An extension line of the rotation central axis of the fourth joint (J4) passes through a placement portion (described later) for an object formed on the base body 51. In the example shown in the figure, the extension line of the fourth joint (J4) is perpendicular to the plane formed by the placement portion.

[0031] According to this configuration, the radius of rotation when the base body 51 is rotated at the fourth joint (J4) can be made small. This makes it possible to perform work in a narrow space. In particular, when the rotation center axis of the fourth joint (J4) is perpendicular to the plane of the mounting part, the positional relationship can be simplified, which makes it easier to perform posture calculations, for example.

[0032] In this embodiment, the object manipulation unit 50 has four drive joints (J5 to J8).

[0033] 2 is an enlarged external perspective view of the object manipulator 50. In this embodiment, the object manipulator 50 has a substantially U-shaped base body 51 that is laid on its side in the figure. A first slide member 52 is slidably attached to one side of the bottom surface of the base body 51 via a first linear joint (JL1) (or a fifth joint (J5)).

[0034] A second slide member 53 is slidably attached to the top surface side of the first slide member 52 via a second translation joint (JL2) (or a sixth joint (J6)). The axes of the first translation joint (JL1) and the second translation joint (JL2) are parallel to each other.

[0035] At this time, the first prismatic joint (JL1) and the second prismatic joint (JL2) are controlled independently and are not interlocked.

[0036] According to such a configuration, the manner in which an object is gripped can be freely controlled, and the first slide member 52 can be prevented from interfering with the object to be gripped.

[0037] In this embodiment, the second slide member 53 is provided with a gripper as an end effector, which includes left and right claws (55L, 55R) and left and right drive units (551L, 551R) that linearly move the claws in the opening and closing directions. These drive units (551L, 551R) respectively constitute a third translation joint (JL3) (or a seventh joint (J7)) and a fourth translation joint (or an eighth joint (J8)). The left and right claws (55L, 55R) are provided with sensors (not shown) that detect contact or force.

[0038] A first camera 56 is provided at the upper end of the base 51 and oriented in an axial direction parallel to the first linear axis (JL1) or the second linear axis (JL2). The first camera 56 has, for example, a function as an RGB camera and a function as a ToF (Time of Flight) camera. As described later, the first camera 56 can be used to recognize markers, objects, and surrounding spaces (gaps) of objects.

[0039] The second slide member 53, particularly near the center of the gripper, is provided with a distance sensor 58 oriented in an axial direction parallel to the first linear axis (JL1) or the second linear axis (JL2). By using this distance sensor 58, it is possible to detect the relative distance between the object and the gripper. This makes it possible to detect whether or not slippage occurs between the object and the jaws 55 when gripping the object.

[0040] A second camera 57 is provided directly above the distance sensor 58 and is oriented in an axial direction parallel to the first linear axis (JL1) or the second linear axis (JL2). The second camera 57 is, for example, a monochrome camera, and captures an identifier such as a barcode attached to an object. Based on this captured image, for example, identification or recognition processing of the object or its contents is performed. Note that the second camera 57 may have a higher resolution and a narrower angle of view than the first camera 56.

[0041] It should be noted that the sensors attached to object manipulation unit 50 are not limited to these sensors (first camera 56, second camera 57, distance sensor 58). Therefore, various known sensors may also be employed.

[0042] 3 is an explanatory diagram showing an example of object gripping by a gripper. In the example shown in FIG. 3, object 201 to be gripped is a box having a rectangular parallelepiped shape. FIG. 3(A) illustrates how object 201 is gripped (or held) by a gripper attached to the tip of slide members (52, 53) extending from base body 51. FIG. 3(B) illustrates a state in which object 201 is pulled into object manipulation unit 50 with slide members (52, 53) placed within base body 51.

[0043] That is, as shown in Fig. 1A, object 201 is gripped by grippers at the tips of slide members (52, 53) extended in multiple stages in the depth direction from base body 51, and then, by pulling the slide members (52, 53) with object 201 gripped onto a planar placement portion on first slide member 52, object 201 can be held in object manipulation unit 50. That is, object manipulation unit 50 as a whole functions as an object holding mechanism.

[0044] According to such a configuration, it becomes possible to, for example, drag object 201 and pull it into object manipulation unit 50, thereby reducing the load on the gripper (or end effector) during object manipulation.

[0045] 4 is a conceptual plan view of a gripper in which left and right claws (55L, 55R) are independently driven. In this embodiment, the left and right claws (55L, 55R) of the gripper are independently driven by respective drive units (551L, 551R).

[0046] As an example, consider a case where a box-shaped object 202 with a rubber band 2021 around the center is gripped by a gripper. The initial state of the gripper and the object 202 is shown in FIG. 1A. When gripping by the gripper starts in this initial state, the left and right claws (55L, 55R) move at the same speed in the closing direction (FIG. 1B). Since the object 202 is positioned slightly shifted to the left of the gripper center in FIG. 1C, the left claw 55L comes into contact with the object 202 first (FIG. 1C). Here, the rubber band 2021 is attached to the object 202, and due to friction with the placement surface, it is not easily moved by the force from the claw 55L. Therefore, the left claw 55L detects a reaction force, and the left claw 55L stops its movement in response to this detection. Thereafter, the right claw 55R moves until it contacts the object 202 in the same manner (FIG. 1D). This completes the gripping.

[0047] According to such a configuration, the holding position of the object with respect to the gripper can be varied, and therefore it is possible to cope with a situation where the object to be gripped does not slide well. In addition, since a gripper having a pair of planar claws (55L, 55R) facing each other in parallel is used, the posture of the object 202 can be corrected.

[0048] Although the present embodiment employs a gripper as the end effector, other mechanisms may be employed, such as a suction mechanism or an electromagnetic mechanism.

[0049] 5 is a functional block diagram of the mobile manipulator 100. As is clear from the diagram, the mobile manipulator 100 has many components described below, which are connected to each other via a bus.

[0050] The mobile manipulator 100 includes a control unit 101, a memory unit 102, a communication unit 103, and a LiDAR device 13.

[0051] The control unit 101 is a calculation device such as a CPU, and executes various processes described below according to a program read from the storage unit 102. The storage unit 102 is a storage device such as a ROM, a RAM, or a flash memory, and stores programs and various data. The communication unit 103 is a communication unit for wireless communication, and transmits and receives information to and from an external device. The LiDAR device 13 is a sensor unit, and acquires the distance, position, shape, and the like of the environment. The acquired information is stored in the storage unit 102, etc., and is used by the control unit 101.

[0052] The articulated robot arm unit 30 is provided with an arm driver 105 including an actuator used to drive the joints, and an arm sensor 106 that acquires the state of the articulated robot arm unit 30 such as the joint angles.

[0053] A wheel drive unit 107, which is a drive circuit for driving the drive wheels (W1, W2), and a wheel sensor 108 for detecting the rotation state of the drive wheels (W1, W2) are provided within the moving mechanism 20. Information detected via the sensor is stored in the memory unit 102 or used by the control unit 101.

[0054] The object manipulating unit 50 is equipped with a left claw driving unit 109 and a right claw driving unit 110 in order to independently drive each joint (JL3, JL4) of the left and right claws (55L, 55R). Also, in order to drive the first linear joint (JL1) and the second linear joint (JL2), the object manipulating unit 50 is equipped with a first linear shaft driving unit 111 and a second linear shaft driving unit 112, which are circuits that drive the first linear joint (JL1) and the second linear joint (JL2), respectively. In addition to this, the object manipulating unit 50 is equipped with a sensor (not shown) that detects force or contact acting on the claw 55.

[0055] In addition, the object manipulation unit 50 is equipped with various sensors, namely, a first camera 56, a second camera 57, and a distance sensor 58, and information obtained via the sensors is stored in the memory unit 102 or used by the control unit 101.

[0056] It should be noted that the above configurations are merely examples, and it goes without saying that various configurations may be realized by adding, modifying, or deleting elements from the configurations.

[0057] (1.2 Mobile manipulator operation) (1.2.1 Picking Operation) FIG. 6 is a flowchart regarding acquisition (picking) of an object on a shelf by the mobile manipulator 100.

[0058] When the process starts, the mobile manipulator 100 uses the moving mechanism 20 to move to the front of a shelf where a target object is located (S11). At this time, the mobile manipulator 100 moves autonomously while estimating its own position using the LiDAR device 13 by so-called Simultaneous Localization and Mapping (SLAM).

[0059] When the mobile manipulator 100 moves in front of the target shelf, it controls the articulated robot arm unit 30 to face the object manipulation unit 50 directly toward the target shelf, and performs recognition processing of the marker attached to the shelf using the first camera 56 provided on the base 51 of the object manipulation unit 50 (S12).

[0060] 7 is a conceptual diagram showing how the first camera 56 recognizes the marker 901. In the figure, for example, a collection of box-shaped objects 203 stacked in two layers is arranged at the front and rear in the depth direction on the shelf board of the shelf 900. A one-dimensional code consisting of a barcode that serves as an identifier for the object 203 (or its contents) is attached to each object 203. A marker 901 is attached to the shelf board of the shelf 900 on the surface facing the mobile manipulator 100. The first camera 56 captures an image of the marker 901, and the control unit 101 performs a process of recognizing the marker 901 in the captured image.

[0061] When the marker recognition process is completed, the control unit 101 of the mobile manipulator performs a process of calculating the difference between the target hand position and the current hand position for predetermined correction based on the position and content of the marker in the image (S13).

[0062] After the difference calculation process, the control unit 101 also performs a process of recognizing whether or not there are gaps on both sides of the object 203 large enough to insert the gripper, based on the image captured by the first camera 56 (S15).

[0063] If the recognition fails or if there are no gaps on either side of the object 203 (S16 YES), the control unit 101 performs error processing (S17). Error processing is, for example, stopping picking and moving to a specified position, or switching the target object to a new object.

[0064] On the other hand, if a gap large enough to insert a gripper is detected on both sides of the object 203 (S16NO), the control unit 101 performs a process of moving the hand, i.e., the object manipulation unit 50, to the reference target hand position based on the difference between the target hand position and the current hand position (S18).

[0065] After the hand movement process, the mobile manipulator 100 performs a predetermined pre-operation process on the object using the articulated robot arm unit 30 and the object manipulation unit 50 (S19). In this embodiment, this pre-operation is an operation to rearrange the object in the depth direction. This pre-operation can stabilize the picking operation described later.

[0066] After the pre-operation process, a process is performed in which second camera 57 provided on second sliding member 52 of object operating unit 50 recognizes the code attached to the object (S20).

[0067] 8 is a conceptual diagram showing how a code 2031 made of a barcode is recognized by the second camera 57. In the figure, the barcode 2031 attached to an object is included in the field of view of the second camera 57. The content of this barcode is recognized from image information, thereby performing a process of recognizing or identifying the object.

[0068] After the recognition process of the code 2031, it is determined whether the object 203 is a target object to be picked, and if it is not a target object to be picked (S21 NO), the control unit 101 performs error processing (S17). On the other hand, if it is a target object to be picked (S21 YES), the mobile manipulator 100 performs a picking operation (S22).

[0069] When the picking operation is completed, mobile manipulator 100 performs an operation to store the picked object in object storage unit 15 (S23). Specifically, mobile manipulator 100 changes the posture of articulated robot arm unit 30 to face the opening face of object manipulation unit 50 directly toward object storage unit 15, and stores the object in object storage unit 15 by controlling the slide members (52, 53) and the gripper. This completes the preparation for transporting the picked object.

[0070] After the storing operation, the mobile manipulator 100 performs an operation of moving together with the stored object (S24), thereby enabling the transportation of the object.

[0071] Fig. 9 is a conceptual diagram showing an example of a series of operations related to picking. In the diagram, a rubber band 2051 is attached around the center of an object 205 to be picked. This rubber band creates a large friction between the object 205 and the surface on which it is placed.

[0072] As a premise, before reaching the state of FIG. 13(A), the mobile manipulator 100 executes a series of processes (S11 to S18) from moving to the front of the shelf to moving the hand.

[0073] As shown in Fig. 1A, when the object pre-operation process (S19) starts, object manipulator 50 reaches out to object 205 located deep in the depth direction, and performs an operation to grip object 205 from the left and right with gripper claws 55. When performing the reaching, object manipulator 50 performs an operation to slide first slide member 52 and second slide member 53 relative to base 51 in a direction increasing the depth in the depth direction. This operation puts gripper claws 53 in a state where they can grip object 205.

[0074] At this time, first sliding member 52 slides at a position higher than the placement surface of object 205.

[0075] With this configuration, the linear motion mechanism can hold the object 205 located deep in the depth direction.

[0076] After grasping the object 205, as shown in the same figure (B), the object manipulation unit 50 performs a pre-manipulation of the object (S19) by lifting the object 205 vertically upward using the articulated robot arm unit 30 to such an extent that a part of the grasped object 205 remains in contact with the placement surface.

[0077] With this configuration, even when the friction between object 205 and the surface on which it is placed is large, for example when rubber band 2051 is wrapped around the center of object 205, object 205 can be moved with a smaller force.

[0078] After lifting object 205, as shown in FIG. 1C, object manipulation unit 50 performs a pre-manipulation (S19) of the object by moving the grasped object 205 to a position toward the front in the depth direction so that part of its bottom surface rubs against the placement surface, and then releasing the gripper to place the object.

[0079] According to such a configuration, the object 205 at the back is temporarily moved to a shallower (closer) position in the depth direction and placed there, and then the object 205 is manipulated again. This makes it possible to keep the various conditions for the object manipulation again constant, thereby realizing stable object manipulation.

[0080] After performing the operations shown in (A) to (C) of the same figure, i.e., the pre-operation processing of the object (S19), the mobile manipulator 100 uses the second camera 57 to perform a recognition process of the code attached to the surface of the object 205 (S20), and performs a determination process of whether the object 205 is an object to be picked (S21).

[0081] According to this configuration, the object recognition conditions can be made constant by rearranging the object in a predetermined position, and stable object recognition can be realized. For example, the recognition process can be performed based on an image generated in an environment where the shooting conditions such as brightness and focus are constant, and the recognition process can be stabilized.

[0082] If it is determined that the object 205 is a picking target (S21 YES), as shown in FIG. 3(D), the articulated robot arm unit 30 performs a picking operation (S22). That is, after performing an operation of moving the entire object manipulation unit 50 vertically downward, the second slide member 53 is used to grasp the object 205 and pull it onto the first slide member 52 (see also FIG. 3(B)). This completes the picking operation.

[0083] The amount of movement at this time is such that the object 205 can be grasped using the second slide member 53 and the first slide member 52 is positioned lower than the placement surface of the object 205.

[0084] According to this configuration, the object 205 can be smoothly placed on the first slide member 52 and manipulated, thereby reducing the load on the gripper.

[0085] After this picking operation, the mobile manipulator 100 performs a process of storing the object 205 in the object storage unit 15 (S23), and then moves (S24).

[0086] The basic picking operation of the mobile manipulator 100 according to this embodiment has been described above, but object manipulation can be performed in various forms depending on the situation.

[0087] (Example of object manipulation for stacked objects (part 1)) 10 is a conceptual diagram of a case where a pre-operation process (S19) is performed on a group of objects formed by piling up objects (206, 207). Each object (206, 207) has a rubber band (2061, 2071) attached around the center thereof.

[0088] As shown in the same figure (A), when the object pre-manipulation process (S19) begins, the object manipulation unit 50 reaches out to the lowest object 207 among the objects located deep in the depth direction, and grasps the object 207 from the left and right with the gripper claws 55.

[0089] After grasping the object 205, as shown in the same figure (B), the object manipulation unit 50 performs a pre-manipulation of the object (S19) by lifting the object 207 vertically upward using the articulated robot arm unit 30 to such an extent that a portion of the grasped object 207 remains in contact with the placement surface.

[0090] After lifting object 205, as shown in FIG. 1C, object manipulation unit 50 performs a pre-manipulation (S19) of the object by moving grasped object 207 to a position toward the front in the depth direction so that part of its bottom surface rubs against the placement surface, and then releasing the gripper to place it.

[0091] According to this configuration, the object (206, 207) at the back is moved to a shallower (nearer) position in the depth direction and placed there, and then the object (206, 207) is manipulated again. This makes it possible to keep the various conditions for the object manipulation again constant, thereby realizing stable object manipulation. In addition, multiple objects can be handled efficiently.

[0092] (Example of picking operations for stacked objects (part 2)) In the above example, a configuration has been shown in which the object is first pre-operated, that is, the object is repositioned to a shallower position in the depth direction, and then the object is recognized and operated, but this is not essential.

[0093] 11 is a conceptual diagram showing an example of an operation when picking an object from a group of objects formed by piling up objects (206, 207) at a deep position in the depth direction. Each object (206, 207) has a rubber band (2061, 2071) attached around its center.

[0094] As shown in Fig. 1A, first, the mobile manipulator 100 reaches out to the uppermost object 206 among the objects located deep in the depth direction. At this time, the height of the first sliding member 52 is approximately the same as the placement surface of the object 206 on the second tier (i.e., the top surface of the object 207 on the first tier).

[0095] After reaching, the mobile manipulator 100 performs a recognition process of the code attached to the surface of the object 206 using the second camera 57, and performs a determination process of whether the object 206 is an object to be picked. If it is determined that the object 206 is an object to be picked, an operation of gripping the object 206 with the gripper claws 55 is performed.

[0096] After the grasping operation, as shown in the same figure (B), the object manipulation unit 50 performs an operation of lifting the grasped object 207 vertically upward using the articulated robot arm unit 30 so that a portion of the grasped object 207 remains in contact with the placement surface.

[0097] After lifting object 206, as shown in FIG. 1C, object manipulator 50 moves gripped object 207 to a predetermined position on first slide member 52 so that part of its bottom surface rubs against the placement surface and first slide member 52. Then, the gripper is released.

[0098] By repeating such an operation, the piled up objects may be stored in the object storage section 15.

[0099] (1.2.2 Placement Operation) FIG. 12 is a flowchart regarding placing of an object by the mobile manipulator 100 at a deep position on a shelf board in the depth direction.

[0100] When the process starts, the mobile manipulator 100 that has stored the object moves to the front of the shelf where the target placement position is located by using the moving mechanism 20 (S31). At this time, the mobile manipulator 100 moves autonomously while estimating its own position using the LiDAR device 13 by so-called SLAM (Simultaneous Localization and Mapping).

[0101] When the mobile manipulator 100 moves in front of the target shelf, it controls the articulated robot arm unit 30 to face the object manipulation unit 50 directly toward the target shelf, and performs a recognition process of the marker attached to the shelf using the first camera 56 provided on the base 51 of the object manipulation unit 50 (S32) (see also Figure 7).

[0102] When the marker recognition process is completed, the control unit 101 of the mobile manipulator 100 performs a process of calculating the difference between the target hand position and the current hand position from the position of the marker in the image and its contents (S33).

[0103] After the difference calculation process, the control unit 101 performs a process of recognizing whether or not there is a space suitable for placing an object at the target placement position on the shelf, based on the image captured by the first camera 56 (S35).

[0104] If the recognition fails or if there is no suitable space (S36 YES), the control unit 101 performs error processing (S37). Error processing is, for example, a process of canceling the placement process and moving to a specified position, or a process of switching the target placement location to a new location.

[0105] On the other hand, if an appropriate space for placing an object is recognized on the shelf (S36 NO), the control unit 101 performs a process to take out one or more objects stored in the object storage unit 15 and place them in advance in the available space (S38). This pre-placement operation can stabilize the actual placement operation described below.

[0106] After the pre-placing process of the storage object, the mobile manipulator 100 performs the actual placing process, that is, the operation process of holding the placed object again and placing it at a deeper position in the depth direction (S40).

[0107] After the placement process is completed, the mobile manipulator 100 folds the articulated robot arm unit 30 so that it is suitable for movement, and performs a process of moving toward the next destination (S41).

[0108] 13 is an explanatory diagram showing an example of the pre-placing operation (S38) on the shelf board of the shelf 900. In the figure, a rubber band 2091 is attached around the center of the stored object 209. This rubber band creates a large friction between the object 209 and the placement surface.

[0109] When the pre-placing process (S38) of the stored object starts, first, as shown in FIG. 1A, the mobile manipulator 100 uses the articulated robot arm unit 30 and the object manipulator unit 50 to take out the object 209 from the object storage unit 15 with the gripper, and faces the object manipulator unit 50 directly to the empty space where the object is to be placed. At this time, the taken-out object 209 is in a state of being grasped by the gripper on the first slide member 52. In addition, the first slide member 52 is disposed at a position approximately the same height as the shelf board or slightly higher.

[0110] Furthermore, the gripper holds the object 209 in a state where it is lifted vertically upward to such an extent that a portion of the held object 209 maintains contact with the placement surface.

[0111] With this configuration, even when the friction between object 209 and the surface on which it is placed is large, for example when a rubber band 2091 is wrapped around the center of object 209, the object can be moved with a smaller force.

[0112] Thereafter, as shown in FIG. 1B, the mobile manipulator 100 moves only the second slide member 53 in the deeper depth direction, thereby moving the object 209 to a shallower position in the depth direction on the shelf board of the shelf 900. After completing this moving process, the mobile manipulator 100 releases the gripper from the object 209.

[0113] After releasing the hold of the object 209, the mobile manipulator 100 performs an operation of retracting the second slide member 55 to the front side in the depth direction, as shown in FIG.

[0114] Through this series of pre-placing operations, the mobile manipulator 100 can place the object 209 stored in the object storage unit 15 at a shallower position in the depth direction on the shelf board. After that, the mobile manipulator 100 again performs a process (S40) of placing the object 209 at a deeper position in the depth direction.

[0115] With this configuration, the object being held is first placed at a position closer to the user, and then placed again at a deeper position in the depth direction. This makes it possible to keep the various conditions for repositioning constant, thereby realizing stable object manipulation (especially placing of the object).

[0116] The basic operation of placing the mobile manipulator 100 according to this embodiment has been described above, but object manipulation can be performed in various forms depending on the situation.

[0117] (Example of placing multiple objects (part 1)) 14 is an explanatory diagram showing an example of a series of operations when multiple objects are placed on the shelf of the shelf 900 in advance and then actually placed on the shelf. In the figure, rubber bands (2051, 2161) are attached around the center of each stored object (215, 216). These rubber bands create a high friction between the objects (215, 216) and the placement surface.

[0118] As a premise, before reaching the state of FIG. 13A, the mobile manipulator 100 executes a series of processes (S31 to S36) from moving in front of the shelf to the recognition process.

[0119] When the object pre-placement process (S38) begins, first, the mobile manipulator 100, as shown in FIG. 1A, uses the articulated robot arm unit 30 and the object manipulation unit 50 to pick up the first object 215 from the object storage unit 15 with a gripper and place it on the shelf at a shallow depth position.

[0120] After placing the first object, the mobile manipulator 100 further uses the articulated robot arm unit 30 and the object manipulation unit 50 to take out the second object 216 from the object storage unit 15 with the gripper and place it on top of the first object, as shown in FIG. 1B. This completes the pre-placing process of the objects (215, 216) (S38).

[0121] After placing the two objects (215, 216) at shallow positions in the depth direction, the mobile manipulator 100 grasps the first object 215 that was initially placed on the shelf board using the gripper as a placement process (S40) as shown in Fig. 1C. After grasping, the mobile manipulator 100 moves the object to a deeper position on the shelf board in the depth direction as shown in Fig. 1D.

[0122] With this configuration, after stacking objects at a shallow depth (nearby position), the bottom object can be held and the group of objects can be moved together to a specified position at the back, enabling stable and efficient object manipulation.

[0123] (Example of placing multiple objects (part 2)) 15 is an explanatory diagram showing another example of the operation of placing an object on an object. In the figure, a rubber band (2111, 2141) is attached around the center of each object (211-214). The rubber band creates a large friction between the object (211-214) and the placement surface.

[0124] When the pre-placing operation (S38) starts, as shown in FIG. 11A, the gripper attached to the second slide member 53 grips the object 214. At this time, the gripper grips the object 214 in a state where it is lifted vertically upward to such an extent that a part of the gripped object 214 maintains a state of contact with the placement surface.

[0125] After gripping, the mobile manipulator 100 moves the second slide member 53 to near the tip of the first slide member 52, as shown in (B) of the same figure, and moves the second slide member 53 to above the object 213 to be placed, which is located at a shallow position in the depth direction of the shelf board. As a result, the lower object 213, the first slide member 52, the object 214 to be placed, and the gripper are aligned in the vertical direction.

[0126] Thereafter, the mobile manipulator 100 performs an operation of pulling only the first slide member 52 toward itself while keeping the position of the second slide member 53 relatively fixed on the object 213, as shown in FIG.

[0127] Finally, as shown in FIG. 13D, the mobile manipulator 100 opens the gripper claws 55 to release the grip, and performs an operation of sliding the second sliding member 52 towards the front.

[0128] With this configuration, the effect of the object 214 being placed on the object 213 being placed, such as the object being placed being pushed by friction, can be minimized, and the objects can be stacked stably.

[0129] (2. Modifications) In the above embodiment, a two-stage linear motion mechanism consisting of a first slide member and a second slide member is used, but the present invention is not limited to such a configuration. Therefore, for example, a multi-stage linear motion mechanism having three or more stages may be used.

[0130] In the above embodiment, the articulated robot arm unit 30 is exemplified as the displacement mechanism for displacing the object manipulation unit 50, but the present invention is not limited to such a configuration. Therefore, for example, other mechanisms such as an elevation mechanism may be adopted as the displacement mechanism.

[0131] Although the embodiments of the present invention have been described above, the above embodiments merely show some of the application examples of the present invention, and the technical scope of the present invention is not limited to the specific configurations of the above embodiments. Moreover, the above embodiments can be appropriately combined within a range where no contradiction occurs. [Industrial Applicability]

[0132] The present invention can be used in industries that manufacture robots and the like. [Explanation of symbols]

[0133] 10 Main body 20 Moving mechanism 30 Articulated robot arm 50 Object operation section 51 Base 52 First slide member 53 Second slide member 55 Claws 100 Mobile Manipulator

Claims

1. A substrate; A first linear moving body that moves linearly along a first axis relative to the base body; a second linear moving body that moves linearly with respect to the first linear moving body along a second axis parallel to the first axis and includes an end effector that manipulates an object; Equipped with The first linear body and the second linear body are driven independently. Object manipulation device.

2. The object manipulation device according to claim 1 , wherein the first linear body further comprises a planar placement portion configured so that the object can be placed thereon.

3. The object manipulation device according to claim 1 , wherein the end effector is a gripper consisting of a pair of claws that can be opened and closed in parallel.

4. The object manipulation device according to claim 3 , wherein the pair of claws are driven independently of each other.

5. The object manipulation device according to claim 3 , wherein each of the claws is provided with a sensor that detects a force acting on the claw.

6. The object manipulation device according to claim 1 , wherein the end effector further comprises a distance sensor oriented in a direction parallel to the second axis.

7. The object manipulation device according to claim 1 , wherein the base further comprises a first camera oriented in a direction parallel to the first axis.

8. The object manipulation device according to claim 1 , wherein the end effector further comprises a second camera oriented in a direction parallel to the second axis.

9. A multi-joint robot arm having an object manipulation device according to any one of claims 1 to 8 at its tip.

10. A mobile robot equipped with a multi-joint robot arm, the robot arm having an object manipulation device according to any one of claims 1 to 8 at its tip.

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