Work-piece takeout device

Abstract

To provide a work-piece takeout device that can take out a work-piece with a high success rate.SOLUTION: A work-piece takeout device described in the present disclosure, which takes out a work-piece one by one out of a plurality of linear work-pieces placed in a three-dimensional space, comprises a first gripping part configured to be able to grip the work-piece, a second gripping part configured to be able to grip the workpiece, a control part that controls respective motion of the first gripping part and the second gripping part, and a gripping-state determining part that determines a gripping state of the work-piece by the first gripping part. When the gripping-state determining part determines that the first gripping part is gripping an end part of the work-piece, the control part makes the second gripping part grip the work-piece gripped by the first gripping part and take out the work-piece from the three-dimensional space.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present disclosure relates to a workpiece removal device for removing a workpiece. [Background technology]

[0002] Patent Document 1 discloses a workpiece extraction device that grips and extracts workpieces one by one from among multiple linear workpieces placed in a three-dimensional space. This workpiece extraction device includes a gripping means for gripping the workpiece, and a control means for controlling the gripping means so that the workpiece gripped by the gripping means traces a circular or rectangular trajectory after the gripping means grips the workpiece. This allows the workpiece extraction device to easily untangle the workpieces from each other and prevent failure to grip the workpieces. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2023-73828 A Summary of the Invention [Problem to be solved by the invention]

[0004] However, the workpiece removal device disclosed in Patent Document 1 had the problem that when the end of a linear workpiece is gripped by the gripping means, it may not be possible to efficiently transmit force to the workpiece gripped by the gripping means, and as a result, the workpiece cannot be removed with a high success rate.

[0005] The present disclosure has been made in consideration of the above background, and has an object to provide a workpiece removal device that is capable of removing a workpiece with a high success rate. [Means for solving the problem]

[0006] The workpiece removal device according to the present disclosure is a workpiece removal device that removes workpieces one by one from a plurality of linear workpieces placed in a three-dimensional space, and includes a first gripping unit configured to be able to grip the workpiece, a second gripping unit configured to be able to grip the workpiece, a control unit that controls the operation of each of the first gripping unit and the second gripping unit, and a gripping state determination unit that determines the gripping state of the workpiece by the first gripping unit, and when the gripping state determination unit determines that the first gripping unit is gripping an end of the workpiece, the control unit causes the second gripping unit to grip the workpiece gripped by the first gripping unit and remove it from the three-dimensional space. As a result, even when the end of the linear workpiece is gripped by the first gripping unit, the second gripping unit can grip the center of the workpiece gripped by the first gripping unit, so that the workpiece removal device can efficiently transmit force to the workpiece to be removed, and as a result, the workpiece can be removed with a high success rate.

[0007] In addition, in the workpiece removal device according to the present disclosure, when the gripping state determination unit determines that the first gripping unit is gripping an end of the workpiece, the control unit causes the second gripping unit to grip the workpiece gripped by the first gripping unit and remove it from the three-dimensional space so as to draw a circular or rectangular trajectory. This allows the workpiece removal device to efficiently transmit force to the workpiece to be removed and to easily untangle the entangled workpiece, thereby enabling the workpiece to be removed with an even higher success rate. Effect of the Invention

[0008] According to the present disclosure, it is possible to provide a workpiece removal device capable of removing a workpiece with a high success rate. [Brief description of the drawings]

[0009] [Figure 1] 1 is a diagram showing a schematic system configuration of a workpiece removal device according to the present disclosure; [Diagram 2]1 is a block diagram showing a schematic system configuration of a control device according to the present disclosure. [Diagram 3] 5 is a flowchart showing an example of an operation of the workpiece removal device according to the present disclosure. [Figure 4] 10 is a flowchart showing another example of the operation of the workpiece extraction device according to the present disclosure. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0010] Hereinafter, specific embodiments to which the present invention is applied will be described in detail with reference to the drawings. However, the present invention is not limited to the following embodiments. In addition, the following description and drawings are appropriately simplified for clarity of explanation.

[0011] <Embodiment 1> 1 is a diagram showing a schematic system configuration of a workpiece extraction device 1 according to the present disclosure. The workpiece extraction device 1 is a device that grips and extracts workpieces one by one from among a plurality of linear workpieces arranged in a three-dimensional space. The linear workpiece is, for example, a cable-like workpiece having a connector, a branching section, etc. The multiple workpieces are linear parts randomly piled up in a box, on a plane, etc.

[0012] Specifically, the workpiece removal device 1 includes robot arms 2 and 3, three-dimensional vision sensors 4 and 5, force sensors 6 and 7, and a control device 8.

[0013] The robot arm 2 is a specific example of a gripping means (grip section). The robot arm 2 is a so-called multi-joint arm, and has, for example, a plurality of links 21, joint sections (wrist joints, elbow joints, shoulder joints, etc.) 22 that rotatably connect the links 21, and an end effector 23 provided at the tip of the links 21 to grip a workpiece.

[0014] Each joint 22 is provided with a rotation sensor such as an encoder that detects rotation information of the joint 22, an actuator such as a servo motor that drives the joint 22, and a force sensor that detects the operating force of the joint 22. The force sensor is, for example, a torque sensor that detects the torque of the joint 22. Each joint 22 is provided with a reduction mechanism or the like. The end effector 23 has, for example, a plurality of fingers. The fingers are provided with joints, actuators, and the like, and each finger is configured to be able to grip a workpiece.

[0015] The robot arm 3 is a specific example of a gripping means (grip unit). The robot arm 3 is a so-called multi-joint arm, and has, for example, a plurality of links 31, joints (wrist joints, elbow joints, shoulder joints, etc.) 32 that rotatably connect the links 31, and an end effector 33 provided at the tip thereof to grip a workpiece.

[0016] Each joint 32 is provided with a rotation sensor such as an encoder that detects rotation information of the joint 32, an actuator such as a servo motor that drives the joint 32, and a force sensor that detects the operating force of the joint 32. The force sensor is, for example, a torque sensor that detects the torque of the joint 32. Each joint 32 is provided with a reduction mechanism or the like. The end effector 33 has, for example, a plurality of fingers. The fingers are provided with joints, actuators, and the like, and each finger is configured to be able to grip a workpiece.

[0017] The three-dimensional vision sensor 4 is a specific example of an acquisition means. The three-dimensional vision sensor 4 acquires three-dimensional information of a plurality of workpieces. The three-dimensional information of the workpieces includes information such as the shape, position (three-dimensional coordinates, etc.) and posture of each workpiece. The three-dimensional vision sensor 4 is provided, for example, on the end effector 23 or link 21 of the robot arm 2. The three-dimensional vision sensor 4 is composed of a camera, a laser sensor, etc. The three-dimensional vision sensor 4 outputs the acquired three-dimensional information of the workpieces to the control device 8.

[0018] The three-dimensional vision sensor 5 is a specific example of an acquisition means. The three-dimensional vision sensor 5 acquires three-dimensional information of a plurality of workpieces. The three-dimensional information of the workpieces includes information such as the shape, position (three-dimensional coordinates, etc.) and posture of each workpiece. The three-dimensional vision sensor 5 is provided, for example, on the end effector 33 or link 31 of the robot arm 3. The three-dimensional vision sensor 5 is composed of a camera, a laser sensor, etc. The three-dimensional vision sensor 5 outputs the acquired three-dimensional information of the workpieces to the control device 8.

[0019] The force sensor 6 is provided, for example, between the link tip side of the robot arm 2 and the end effector 23. When the end effector 23 grips a workpiece, the weight of the workpiece is applied to the end effector 23. The force sensor 6 detects the weight of the workpiece gripped by the end effector 23.

[0020] The force sensor 7 is provided, for example, between the link tip side of the robot arm 3 and the end effector 33. When the end effector 33 grips a workpiece, the weight of the workpiece is applied to the end effector 33. The force sensor 7 detects the weight of the workpiece gripped by the end effector 33.

[0021] The control device 8 performs various types of arithmetic processing and control processing for the robot arms 2 and 3. The control device 8 has a hardware configuration of a normal computer including, for example, a processor 8a such as a CPU (Central Processing Unit) or a GPU (Graphics Processing Unit), an internal memory 8b such as a RAM (Random Access Memory) or a ROM (Read Only Memory), a storage device 8c such as an HDD (Hard Disk Drive) or an SDD (Solid State Drive), an input / output I / F 8d for connecting peripheral devices such as a display, and a communication I / F 8e for communicating with devices outside the device.

[0022] 2 is a block diagram showing a schematic system configuration of the control device 8. The control device 8 has a candidate calculation unit 81, a robot control unit 82, and a gripping state determination unit 83.

[0023] The candidate calculation unit 81 calculates at least one gripping candidate point that is a candidate for the gripping point of the workpiece when the end effector 23 of the robot arm 2 grips the workpiece, based on the three-dimensional information of the workpiece acquired by the three-dimensional vision sensor 4. In addition, the candidate calculation unit 81 calculates at least one gripping candidate point that is a candidate for the gripping point of the workpiece when the end effector 33 of the robot arm 3 grips the workpiece, based on the three-dimensional information of the workpiece acquired by the three-dimensional vision sensor 5.

[0024] For example, the candidate calculation unit 81 calculates depth information indicating the height position of each workpiece based on the three-dimensional information of the workpiece acquired by the three-dimensional vision sensor 4. The candidate calculation unit 81 detects a convex portion protruding in the height direction based on the calculated depth information of each workpiece. Based on the calculated depth information, the candidate calculation unit 81 binarizes, for example, a point at a predetermined height or higher as 1 and a point at a height less than the predetermined height as 0, and detects a point at which the value is 1 as a convex portion. The candidate calculation unit 81 may set the convex portion detected as described above as a grip candidate point. Thereby, a convex portion that is easy to grip by the end effector 23 can be set as a grip candidate point. Similarly, the candidate calculation unit 81 may calculate the depth information of each workpiece based on the three-dimensional information of the workpiece acquired by the three-dimensional vision sensor 5, and set the convex portion detected based on the calculation result as a grip candidate point for the end effector 33. The candidate calculation unit 81 outputs a plurality of grip candidate points calculated as described above to the robot control unit 82.

[0025] The robot control unit 82 is a specific example of a control means. The robot control unit 82 controls the operation of each of the robot arms 2 and 3. The robot control unit 82 feedback-controls the robot arm 2 by controlling the actuators of each joint in the robot arm 2 based on, for example, rotation information (rotation angle, etc.) from a rotation sensor of each joint in the robot arm 2 and an operation force from a force sensor of each joint. The robot control unit 82 also feedback-controls the robot arm 3 by controlling the actuators of each joint in the robot arm 3 based on, for example, rotation information (rotation angle, etc.) from a rotation sensor of each joint in the robot arm 3 and an operation force from a force sensor of each joint. Thereby, the robot control unit 82 can move the end effectors 23 and 33 of the robot arms 2 and 3 to desired positions.

[0026] Furthermore, the robot control unit 82 controls the actuators of the fingers of the end effectors 23, 33 to control gripping and releasing of the workpiece by each of the end effectors 23, 33. As a result, the robot control unit 82 can control each of the robot arms 2, 3 to grip and move the workpiece.

[0027] Here, the robot control unit 82 selects one gripping candidate point from the multiple gripping candidate points calculated by the candidate calculation unit 81. Then, the robot control unit 82 controls the robot arm 2 so that the end effector 23 of the robot arm 2 grips the workpiece at the gripping candidate point, based on the three-dimensional information of the workpiece acquired by the three-dimensional vision sensor 4. Similarly, the robot control unit 82 controls the robot arm 3 so that the end effector 33 of the robot arm 3 grips the workpiece at the gripping candidate point, based on the three-dimensional information of the workpiece acquired by the three-dimensional vision sensor 5.

[0028] The gripping state determination unit 83 determines the gripping state of the workpiece by each of the end effectors 23 and 33. Specifically, the gripping state determination unit 83 determines which part of the workpiece the end effector 23 is gripping. Similarly, the gripping state determination unit 83 determines which part of the workpiece the end effector 33 is gripping.

[0029] For example, when the weight of the workpiece lifted to a predetermined height position by the end effector 23 is less than a predetermined weight W1, the gripping state determination unit 83 determines that the robot arm 2 is not efficiently transmitting force to the workpiece, that is, the end effector 23 is gripping the end of the workpiece. Further, when the weight of the workpiece lifted to a predetermined height position by the end effector 23 is equal to or greater than the predetermined weight W1 and less than a predetermined weight W2 (where W1 < W2), the gripping state determination unit 83 determines that the robot arm 2 is efficiently transmitting force to the workpiece, that is, the end effector 23 is gripping the central part of the workpiece. Furthermore, when the weight of the workpiece lifted to a predetermined height position by the end effector 23 is equal to or greater than the predetermined weight W2, the gripping state determination unit 83 determines that the end effector 23 is gripping the entangled workpiece. Similarly, the gripping state determination unit 83 also determines the gripping state of the workpiece gripped by the end effector 33 based on the weight of the workpiece. Then, the gripping state determination unit 83 outputs the determination result to the robot control unit 82. Note that the entangled workpiece is not limited to the workpiece that is entangled by itself, but also includes the workpiece that is entangled with other workpieces.

[0030] Note that the gripping state determination unit 83 is not limited to determining the gripping state of the workpiece based on the weight of the workpiece lifted to a predetermined height position by either of the end effectors 23 and 33. For example, the gripping state of the workpiece may be determined based on the three-dimensional information of the workpiece acquired by either of the three-dimensional vision sensors 4 and 5.

[0031] Here, the robot control unit 82 controls the operations of the robot arms 2 and 3 based on the determination result of the gripping state determination unit 83.

[0032] For example, when the gripping status determination unit 83 determines that the end effector 23 is gripping an end of the workpiece, the robot control unit 82 causes the end effector 33 to grip the workpiece gripped by the end effector 23. At this time, since the end effector 23 is already gripping an end of the workpiece, the end effector 33 can grip the center of the workpiece with a high probability. After that, the robot control unit 82 releases the workpiece from the end effector 23.

[0033] Also, for example, when the gripping status determination unit 83 determines that the end effector 23 is gripping the center of the workpiece or that the end effector 23 is gripping a tangled workpiece, the robot control unit 82 does not cause the end effector 33 to grip the workpiece being gripped by the end effector 23, but rather causes the end effector 23 to continue gripping the workpiece.

[0034] Thereafter, the robot control unit 82 controls either the robot arm 2 or 3 so that the workpiece gripped by either the end effector 23 or 33 describes a circular trajectory. By controlling either the robot arm 2 or 3 so that either the end effector 23 or 33 describes a circular trajectory, the robot control unit 82 causes the workpiece gripped by either the end effector 23 or 33 to also describe a circular trajectory as described above.

[0035] For example, a linear workpiece such as a cable is often placed in a circularly wound state. Therefore, the robot control unit 82 can easily untangle the tangled workpiece by controlling either the robot arm 2 or 3 so that the workpiece grasped by either the end effector 23 or 33 moves in a circular trajectory.

[0036] The above-mentioned circular trajectory may include not only a perfect circle but also an ellipse. The robot control unit 82 may also control either the robot arm 2 or 3 so that the workpiece held by either the end effector 23 or 33 draws a rectangular trajectory. The robot control unit 82 may also control either the robot arm 2 or 3 so that the workpiece held by either the end effector 23 or 33 reciprocates along a circular or rectangular trajectory.

[0037] Furthermore, the robot control unit 82 may control either the robot arm 2 or 3 so that the workpiece gripped by either the end effector 23 or 33 rotates while revolving so as to describe a circular orbit, thereby enabling the robot control unit 82 to more easily untangle the tangled workpiece.

[0038] Furthermore, the robot control unit 82 may further control either the robot arm 2 or 3 so that the workpiece gripped by either the end effector 23 or 33 vibrates. This allows the robot control unit 82 to more easily untangle the workpiece. The magnitude of the vibration is preferably set according to the size of a portion of the workpiece where tangling is likely to occur, such as a connector or a branching portion.

[0039] For example, the robot control unit 82 may use a torque sensor (not shown) provided on either the end effector 23, 33 to detect the rotational torque when moving the workpiece along a circular trajectory, and control the vibration to be increased as the detected rotational torque increases.

[0040] Next, an example of the operation of the workpiece picking device 1 will be described with reference to Fig. 3. Fig. 3 is a flow chart showing an example of the operation of the workpiece picking device 1.

[0041] First, the workpiece picking device 1 acquires three-dimensional information of a plurality of workpieces using, for example, the three-dimensional vision sensor 4 (step S101). Then, the workpiece picking device 1 calculates a gripping candidate point of the workpiece to be picked based on the three-dimensional information of the plurality of workpieces using the candidate calculation unit 81 of the control device 8 (step S102). Then, the workpiece picking device 1 controls the robot arm 2 using the robot control unit 82 of the control device 8 so that the end effector 23 grips the workpiece to be picked at the gripping candidate point and lifts it up to a predetermined height (step S103).

[0042] Thereafter, the workpiece unloading device 1 uses the gripping status determination unit 83 of the control device 8 to determine the gripping status of the workpiece by the end effector 23. Specifically, the workpiece unloading device 1 uses the gripping status determination unit 83 of the control device 8 to determine whether the end effector 23 is gripping an end of the workpiece based on whether the weight of the workpiece gripped by the end effector 23 and lifted to a predetermined height position is less than a predetermined weight W1 (step S104).

[0043] For example, if the weight of the workpiece gripped by the end effector 23 and lifted to a predetermined height is less than the predetermined weight W1 (YES in step S104), the gripping state determination unit 83 determines that the robot arm 2 cannot efficiently transmit force to the workpiece, that is, that the end effector 23 is gripping the end of the workpiece. In this case, the workpiece extraction device 1 uses the robot control unit 82 of the control device 8 to make the end effector 33 grip the workpiece gripped by the end effector 23 (step S105). At this time, since the end effector 23 has already gripped the end of the workpiece, the end effector 33 can grip the center of the workpiece with a high probability. After that, the workpiece extraction device 1 uses the robot control unit 82 of the control device 8 to make the end effector 23 release the workpiece.

[0044] On the other hand, if the weight of the workpiece gripped by the end effector 23 and lifted to the predetermined height is equal to or greater than the predetermined weight W1 (NO in step S104), the gripping state determination unit 83 determines that the end effector 23 is gripping the center of the workpiece or gripping a tangled workpiece. In this case, the workpiece unloading device 1 uses the robot control unit 82 of the control device 8 to not cause the end effector 33 to grip the workpiece gripped by the end effector 23, but to keep the end effector 23 gripping the workpiece.

[0045] Thereafter, the workpiece unloading device 1 uses the robot control unit 82 of the control device 8 to control either the robot arm 2 or 3 so that the workpiece gripped by either the end effector 23 or 33 draws a circular trajectory (step S106).

[0046] Then, the workpiece unloading device 1 uses the robot control unit 82 of the control device 8 to take out the workpiece gripped by either the end effector 23, 33 from the three-dimensional space and move it to a desired position (step S107).

[0047] In this way, with the workpiece removal device 1 disclosed herein, even if one end effector grips the end of a linear workpiece, the other end effector can grip the center of the workpiece gripped by one gripping portion, thereby efficiently transmitting force to the workpiece to be removed, and as a result, the workpiece can be removed with a high success rate.

[0048] Moreover, the workpiece removal device 1 according to the present disclosure controls the robot arm so that the workpiece gripped by any of the end effectors moves in a circular or rectangular trajectory, which not only enables the workpiece removal device 1 according to the present disclosure to efficiently transmit force to the workpiece to be removed, but also makes it possible to easily untangle the workpiece, thereby enabling the workpiece to be removed with a higher success rate.

[0049] <Embodiment 2> Next, another example of the operation of the workpiece picking device 1 will be described with reference to Fig. 4. Fig. 4 is a flow chart showing another example of the operation of the workpiece picking device 1.

[0050] First, the workpiece picking device 1 acquires three-dimensional information of a plurality of workpieces using, for example, the three-dimensional vision sensor 4 (step S201). Then, the workpiece picking device 1 calculates a gripping candidate point of the workpiece to be picked based on the three-dimensional information of the plurality of workpieces using the candidate calculation unit 81 of the control device 8 (step S202). Then, the workpiece picking device 1 controls the robot arm 2 using the robot control unit 82 of the control device 8 so that the end effector 23 grips the workpiece to be picked at the gripping candidate point and lifts it up to a predetermined height (step S203).

[0051] Thereafter, the workpiece unloading device 1 uses the gripping state determining unit 83 of the control device 8 to determine the gripping state of the workpiece by the end effector 23.

[0052] Specifically, first, the workpiece removal device 1 uses the gripping status determination unit 83 of the control device 8 to determine whether the end effector 23 is gripping an end of the workpiece based on whether the weight of the workpiece gripped by the end effector 23 and lifted to a predetermined height position is less than a predetermined weight W1 (step S204).

[0053] For example, if the weight of the workpiece gripped by the end effector 23 and lifted to a predetermined height is less than the predetermined weight W1 (YES in step S204), the gripping status determination unit 83 determines that the robot arm 2 cannot efficiently transmit force to the workpiece, that is, that the end effector 23 is gripping the end of the workpiece. In this case, the workpiece extraction device 1 uses the robot control unit 82 of the control device 8 to make the end effector 33 grip the workpiece gripped by the end effector 23 (step S205). At this time, since the end effector 23 is already gripping the end of the workpiece, the end effector 33 can grip the center of the workpiece with a high probability. After that, the workpiece extraction device 1 uses the robot control unit 82 of the control device 8 to make the end effector 23 release the workpiece.

[0054] Thereafter, the workpiece unloading device 1 uses the gripping status determination unit 83 of the control device 8 to determine whether the end effector 33 is gripping an end of the workpiece based on whether the weight of the workpiece gripped by the end effector 33 and lifted to a predetermined height is less than a predetermined weight W1 (step S204). The processes of steps S204 to S205 are repeated until the weight of the workpiece gripped by either of the end effectors 23, 33 and lifted to a predetermined height becomes equal to or greater than the predetermined weight W1.

[0055] If the weight of the workpiece grasped by either of the end effectors 23, 33 and lifted to a predetermined height is equal to or greater than the predetermined weight W1 (NO in step S204), then the workpiece removal device 1 uses the gripping status determination unit 83 of the control device 8 to determine whether or not the end effector 23 is gripping a tangled workpiece based on whether the weight of the workpiece grasped by either of the end effectors 23, 33 and lifted to a predetermined height is less than the predetermined weight W2 (step S206).

[0056] For example, if the weight of the workpiece gripped by either of the end effectors 23, 33 and lifted to a predetermined height is equal to or greater than the predetermined weight W2 (NO in step S206), the gripping status determination unit 83 determines that either of the end effectors 23, 33 is gripping a tangled workpiece. In this case, the workpiece extraction device 1 uses the robot control unit 82 of the control device 8 to control either of the robot arms 2, 3 so that the workpiece gripped by either of the end effectors 23, 33 draws a circular trajectory (step S207). This allows the workpiece extraction device 1 to easily untangle the tangled workpiece gripped by either of the end effectors 23, 33. After that, the workpiece extraction device 1 returns to the process of step S204.

[0057] When the weight of the workpiece grasped by either of the end effectors 23, 33 and lifted to a predetermined height is equal to or greater than the predetermined weight W1 and less than the predetermined weight W2 (YES in step S206), the grasping state determination unit 83 determines that either of the robot arms 2, 3 is efficiently transmitting force to the workpiece, that is, either of the end effectors 23, 33 is grasping the center of the workpiece without entanglement. In this case, the workpiece unloading device 1 uses the robot control unit 82 of the control device 8 to take out the workpiece grasped by either of the end effectors 23, 33 from the three-dimensional space and move it to a desired position without moving it along a circular trajectory (step S208).

[0058] In this way, with the workpiece removal device 1 disclosed herein, even if one end effector grips the end of a linear workpiece, the other end effector can grip the center of the workpiece gripped by one gripping portion, thereby efficiently transmitting force to the workpiece to be removed, and as a result, the workpiece can be removed with a high success rate.

[0059] Moreover, the workpiece picking device 1 according to the present disclosure controls the robot arm so that the workpiece gripped by any of the end effectors traces a circular or rectangular trajectory only when the workpiece gripped by any of the end effectors is entangled. This allows the workpiece picking device 1 according to the present disclosure to reduce the processing load.

[0060] In the present disclosure, a part or all of the processing of the workpiece removal device 1 can be realized by causing a CPU (Central Processing Unit) to execute a computer program.

[0061] The above-mentioned program includes a set of instructions (or software code) for making the computer perform one or more functions described in the embodiment when the program is loaded into the computer. The program may be stored in a non-transitory computer-readable medium or a tangible storage medium. By way of example and not limitation, the computer-readable medium or the tangible storage medium includes a random-access memory (RAM), a read-only memory (ROM), a flash memory, a solid-state drive (SSD) or other memory technology, a CD-ROM, a digital versatile disc (DVD), a Blu-ray® disk or other optical disk storage, a magnetic cassette, a magnetic tape, a magnetic disk storage or other magnetic storage device. The program may be transmitted on a transitory computer-readable medium or a communication medium. By way of example and not limitation, the transitory computer-readable medium or the communication medium includes an electrical, optical, acoustic, or other form of propagating signal.

[0062] Although the present disclosure has been described above with reference to the embodiments, the present disclosure is not limited to the above-mentioned embodiments. Various modifications that can be understood by a person skilled in the art can be made to the configuration and details of the present disclosure within the scope of the present disclosure. Furthermore, each embodiment can be appropriately combined with other embodiments.

[0063] A part or all of the above-described embodiments can be described as, but is not limited to, the following supplementary notes.

[0064] (Appendix 1) A method for removing a workpiece by a workpiece removal device that removes a workpiece one by one from a plurality of linear workpieces placed in a three-dimensional space, comprising the steps of: The workpiece is gripped by a first gripping portion, Determining a gripping state of the workpiece by the first gripping unit; When it is determined that the first gripping unit is gripping the end portion of the workpiece, a second gripping unit is caused to grip the workpiece gripped by the first gripping unit and to remove the workpiece from the three-dimensional space. How to remove the workpiece.

[0065] (Appendix 2) When it is determined that the first gripping unit is gripping the end portion of the workpiece, the second gripping unit is caused to grip the workpiece gripped by the first gripping unit and to take the workpiece out of the three-dimensional space so as to draw a circular or rectangular trajectory. The method for removing the workpiece described in Appendix 1.

[0066] (Appendix 3) A control program for causing a computer to execute a workpiece removal process in a workpiece removal device that removes workpieces one by one from a plurality of linear workpieces placed in a three-dimensional space, A process of gripping the workpiece by a first gripping unit; A process of determining a gripping state of the workpiece by the first gripping unit; When it is determined that the first gripping unit is gripping an end portion of the workpiece, a process of causing a second gripping unit to grip the workpiece gripped by the first gripping unit and remove the workpiece from the three-dimensional space; A control program that causes a computer to execute the above.

[0067] (Appendix 4) When it is determined that the first gripping unit is gripping the end portion of the workpiece, the computer executes a process of causing a second gripping unit to grip the workpiece gripped by the first gripping unit and to remove the workpiece from the three-dimensional space so as to draw a circular or rectangular trajectory. 4. The control program according to claim 3. [Explanation of symbols]

[0068] REFERENCE SIGNS LIST 1 workpiece removal device, 2,3 robot arm, 4,5 three-dimensional vision sensor, 6,7 force sensor, 8 control device, 21,31 link, 22,32 joint, 23,33 end effector, 81 candidate calculation unit, 82 robot control unit, 83 gripping state determination unit

Claims

1. A workpiece removal device that removes workpieces one by one from a plurality of linear workpieces placed in a three-dimensional space, A first gripping portion configured to be able to grip the workpiece; A second gripping portion configured to be able to grip the workpiece; A control unit that controls the operation of each of the first gripping unit and the second gripping unit; A gripping state determination unit that determines a gripping state of the workpiece by the first gripping unit; Equipped with When the gripping state determination unit determines that the first gripping unit is gripping an end portion of the workpiece, the control unit causes the second gripping unit to grip the workpiece gripped by the first gripping unit and remove the workpiece from the three-dimensional space. Work removal device.

2. When the gripping state determination unit determines that the first gripping unit is gripping an end of the workpiece, the control unit causes the second gripping unit to grip the workpiece gripped by the first gripping unit and to remove the workpiece from the three-dimensional space so as to draw a circular or rectangular trajectory. The workpiece removal device according to claim 1 .

3. The gripping state determination unit determines that the first gripping unit is gripping an end of the workpiece when the weight of the workpiece received by the first gripping unit is less than a first predetermined weight in a state in which the workpiece gripped by the first gripping unit is lifted to a predetermined height position. The workpiece removal device according to claim 1 .

4. When the gripping state determination unit determines that the first gripping unit is gripping the center of the workpiece, the control unit causes the first gripping unit to remove the gripped workpiece from the three-dimensional space. The workpiece removal device according to claim 1 .

5. The gripping state determination unit further determines a gripping state of the workpiece by the second gripping unit, When the gripping state determination unit determines that the second gripping unit is gripping the center of the workpiece, the control unit causes the second gripping unit to remove the gripped workpiece from the three-dimensional space. The workpiece removal device according to claim 1 .

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