Article conveyance system
The article conveying system addresses the challenge of transferring articles of varying heights and stacks by using a robot and synchronized support base adjustments to prevent damage during conveyance, ensuring stable and efficient transport.
Patent Information
- Authority / Receiving Office
- WO · WO
- Patent Type
- Applications
- Current Assignee / Owner
- FANUC LTD
- Filing Date
- 2024-10-29
- Publication Date
- 2026-05-07
AI Technical Summary
Conventional conveying robots struggle to transfer articles of varying heights or stacked articles without causing damage during conveyance.
An article conveying system comprising a robot with a hand, a support base moving device, and a control device that uses 3D image sensors to adjust the support base's height and synchronize the robot's movements to prevent article dropping.
Effectively transports articles of varying heights and stacked configurations by minimizing contact and collision risks, ensuring stable and efficient conveyance.
Smart Images
Figure JP2024038441_07052026_PF_FP_ABST
Abstract
Description
Article conveying system
[0001] The present disclosure relates to an article conveying system.
[0002] Conventionally, a conveying robot that conveys luggage from a shelf at the loading location to a shelf at the unloading location is known (see, for example, Patent Document 1). This conveying robot includes a lifting mechanism that temporarily places and lifts luggage, a robot arm mounted on the lifting mechanism that grips the luggage, and an image acquisition unit that acquires the height information of the shelf.
[0003] Japanese Patent Application Laid-Open No. 2015-178141
[0004] When articles stacked in multiple stages are loaded, and / or when articles of different heights are loaded, it is not possible to transfer the load to the destination only with the height information of the shelf on which the articles are placed. Therefore, even in such cases, it is desired to convey the articles that have been loaded at the loading location to the unloading location while effectively protecting them from damage due to dropping during conveyance.
[0005] One aspect of the present disclosure is an article conveying system including a robot installed on an installation surface, the robot picking up an article that has been loaded at the loading location with a hand attached to the tip, a support base moving device including a support base movable with respect to the installation surface, and a control device that controls the robot and the support base moving device so as to move the article from the loading location to the unloading location.
[0006] This is a perspective view showing an article transport system according to one embodiment of the present disclosure. This is a perspective view showing an example of a support platform lifting device provided in the article transport system of Figure 1. This is a flowchart explaining the operation of the article transport system of Figure 1. This is a schematic diagram showing the heights of the top surface of an article picked up by the hand of the article transport system of Figure 1, the support surface, and the top surface of the roller conveyor. This is a flowchart explaining the contents of step S2 in Figure 3. This is a schematic diagram showing the heights of the top surface of an article picked up by the hand of the article transport system of Figure 1, the top surface of a foreground article, the support surface, and the top surface of the roller conveyor. This is a schematic diagram showing the height of the location where the article picked up by the hand of the article transport system of Figure 1 was placed and the height dimension of the article. This is a schematic diagram explaining the operation of bringing the support surface into contact with or close to the bottom surface of an article being picked up by the hand in the article transport system of Figure 1. This is a schematic diagram explaining the operation of raising an article to the height of the roller conveyor while maintaining the relationship between the bottom surface of the article and the support surface in the article transport system of Figure 1. This is a flowchart explaining the operation of a modified version of the article transport system of Figure 1. This is a schematic diagram showing another modified version of the article transport system of Figure 1. This is a flowchart explaining the operation of the article transport system of Figure 9. This is a schematic diagram illustrating the operation of another modified version of the item handling system in Figure 1. This is a schematic diagram illustrating the operation of the item handling system in Figure 11 following Figure 11. This is a schematic diagram illustrating the operation of the item handling system in Figure 11 following Figure 12. This is a perspective view showing a modified version of the support platform lifting device in Figure 2. This is a perspective view showing another modified version of the support platform lifting device in Figure 2. This is a perspective view showing another modified version of the support platform lifting device in Figure 2. This is a flowchart illustrating the operation of a modified version of the item handling system in Figure 1 where the robot and the support platform lifting device are not synchronized. This is a flowchart illustrating the operation of another modified version of the item handling system in Figure 1 where the robot and the support platform lifting device are not synchronized.
[0007] Below, an article transport system 100 according to one embodiment of the present disclosure will be described with reference to the drawings. The article transport system 100 according to this embodiment is a system that, for example as shown in Figure 1, picks up one by one multiple articles W that have been brought into the loading area by a flat pallet 200 and transports them to a roller conveyor 300 which is the loading area. In the example shown in Figure 1, the articles W are rectangular parallelepiped corrugated cardboard boxes, stacked in multiple layers on the flat pallet 200. Although the same shape of corrugated cardboard boxes is shown, there may be a mix of boxes with different widths, depths, or heights. Articles W may be other articles besides corrugated cardboard boxes. The article W is not limited to a rectangular parallelepiped shape, and any article W that can be picked up or grasped by the hand 17 described later may be used.
[0008] The item transport system 100 comprises a robot 1 installed on the surface to be installed, for example, the floor, a support platform lifting device (support platform moving device) 2 also installed on the floor next to the robot 1, and a control device 3. The item transport system 100 also includes a three-dimensional image sensor (height information acquisition means) 4 positioned downwards above the loading area.
[0009] In the example shown in Figure 1, robot 1 is a vertical six-axis articulated robot, but the type of robot 1 can be any type selected depending on the size, weight, and operating range of the item W to be transported. The robot 1 in Figure 1 comprises a base 11 installed on the floor, a slewing body 12 rotatably supported relative to the base 11 around a vertical first axis, and a first arm 13 rotatably supported relative to the slewing body 12 around a horizontal second axis. The robot 1 also comprises a second arm 14 rotatably supported relative to the first arm 13 around a third axis parallel to the second axis, and a three-axis wrist unit 15 attached to the tip of the second arm 14.
[0010] The rotating body 12, the first arm 13, the second arm 14, and the wrist unit 15 are each driven by a motor and a reduction gear (not shown). This allows the robot 1 to position the flange 16 at the tip of the wrist unit 15 in any position and orientation within its operating range.
[0011] Furthermore, the robot 1 includes a hand 17 attached to the flange 16 at the tip of the wrist unit 15. The hand 17 includes, for example, a suction pad 18 that attracts an article W by negative pressure. If the article W is made of a magnetic material, a hand equipped with an electromagnet that attracts it by magnetic force may be used. Also, the hand 17 is not limited to one that attracts the article W, but may also be one that grips the article W.
[0012] The support base lifting device 2 is a single-axis linear motion mechanism that moves a flat plate-shaped support base 21, which has a support surface 2a arranged substantially horizontally, in a linear manner vertically. As shown in Figure 2, the support base lifting device 2 comprises a columnar base 22 installed on the floor surface, a guide rail 23 and a ball screw 24 extending vertically within the base 22, and a slider 25 supported on the guide rail 23 so as to be able to move up and down. A motor 26 is fixed to the base 22, and the motor 26 rotates the ball screw 24 around its axis. The nut 27 of the ball screw 24 is fixed to the slider 25, and the slider 25 can be raised or lowered depending on the rotation direction of the ball screw 24.
[0013] The support base 21 is fixed to the slider 25 in a cantilevered manner. As shown in Figure 1, the support base lifting device 2 is installed so that the support base 21 extends across the space between the robot 1 and the loading area. The tip of the cantilevered support base 21 is positioned horizontally close to the roller conveyor 300, which is the unloading area. In the figure, reference numeral 28 denotes a wall provided along the edge of the support base 21 on the robot 1 side, which prevents further movement of the item W mounted on the support surface 2a toward the robot 1. As an example of a support base moving device, the support base lifting device 2 is shown to raise and lower the support base 21, but a device that also includes a mechanism to move the support base 21 horizontally or rotates may be adopted.
[0014] The 3D image sensor 4 acquires a 3D image of the top surface of the item W inside the flat pallet 200 that has been brought into the loading area. The 3D image includes shape, orientation, and height information of the top surface of the item W.
[0015] The control device 3 comprises at least one processor, memory, and storage unit. The processor consists of a CPU (Central Processing Unit) or a quantum processor, etc. The memory consists of DRAM (Dynamic Random Access Memory), etc., and temporarily stores data necessary for the processor to perform processing. The storage unit consists of a hard disk, SSD (Solid State Drive), flash memory, etc. The storage unit stores the operation program to be executed by the processor and the data necessary for its operation.
[0016] The control device 3 is connected to the robot 1, the support platform lifting device 2, and the 3D image sensor 4. The control device 3 controls the robot 1 and the support platform lifting device 2 based on the information acquired by the 3D image sensor 4.
[0017] Specifically, as shown in Figure 3, the control device 3 uses a three-dimensional image sensor 4 to acquire a three-dimensional image of the item W on the flat pallet 200 that has been brought to the loading location from above (step S1). As a result, as shown in Figure 4, the shape, direction, and height A of the top surface of the item W to be picked up by the robot 1, as well as height information of objects around the item W, can be acquired.
[0018] Then, the control device 3 sets the height B of the support stand 21 to be moved (step S2). Specifically, as shown in Figure 5, first, it is determined whether or not the maximum height of the item W on the flat pallet 200 is known (step S21). If the maximum height is unknown, the height B of the support stand 21 to be moved is set to the lowest position of the support stand lifting device 2 (step S22).
[0019] Next, if the maximum height of the item W is known in step S21, the control device 3 determines from the image acquired by the 3D image sensor 4 whether or not there is an item Wf in front of it (step S23). The item Wf in front is the item located between the item W to be picked up and the robot 1, that is, in front of the item W. If there is no item Wf in front of it, the control device 3 sets the height B of the support surface 2a of the support stand 21 to be moved to a lower height than the estimated height of the bottom surface of the item W (the height when the item W has its maximum height) (step S24). This allows the item W to be moved onto the support surface 2a without the bottom surface of the item W coming into contact with the support surface 2a, even when the item W with its maximum height is pulled out horizontally.
[0020] Furthermore, if it is determined in step S23 that there is an item Wf in front of the user, the control device 3 determines whether the estimated height of the bottom surface of the item W to be picked up is lower than the height G of the top surface of the item Wf in front of the user (step S25). Figure 6 shows the height G of the top surface of the item Wf in front of the user.
[0021] In step S25, if it is determined that the estimated height of the bottom surface of item W is greater than or equal to the height G of the top surface of the item Wf in front, the process proceeds to step S24. In step 25, if it is determined that the estimated height of the bottom surface of item W is lower than the height G of the top surface of the item Wf in front, the control device 3 activates the robot 1. The robot then moves the item W, which is being held by the hand 17, to a position where the height of the bottom surface of item W is higher than the height G of the top surface of the item Wf in front (step S26). This allows item W to be positioned at a height where it can be pulled horizontally towards the front, even if it has its maximum height, over the top surface of the item Wf in front. In this case, the height B of the support surface 2a of the support base 21 to be moved is set to the height G of the top surface of the item Wf in front (step S27).
[0022] Next, the control device 3 controls the support base lifting device 2 to move the support base 21 to the height B of the support surface 2a set in step S2 (step S3). Furthermore, the control device 3 controls the robot 1 to position the hand 17 above the item W in a position and orientation that matches the shape and orientation of the upper surface of the item W acquired by the 3D image sensor 4. Then, as shown in Figure 6, the hand 17 is lowered so that the suction pad 18 of the hand 17 comes into contact with the upper surface of the item W, and the suction pad 18 is activated to allow the hand 17 to suction the upper surface of the item W.
[0023] Furthermore, as shown in Figure 7, the control device 3 controls the robot 1 to position the item W picked up by the hand 17 vertically above the support surface 2a of the support base 21 (step S4). In this case, it is preferable for the robot 1 to slightly lift the item W on the flat pallet 200 and move it above the support base 21. By separating the contact between the bottom surface of the item W and the item W below it, the ease of transport is improved and the possibility of the picked-up item W falling is reduced. As a result, one item W is removed from the loading area.
[0024] In this state, the height C of the location where the picked-up item W was placed is obtained from the 3D image acquired by the 3D image sensor 4 at this point (step S5). Then, the height dimension (A-C) of the picked-up item W is obtained by subtracting height C from height A. Since the height D of the top surface of the item W being held by the hand 17 is known from the position information of each axis of the robot 1, the height dimension (A-C) of the item W is subtracted from height D. This allows the height of the bottom surface of the item W being held by the hand 17 to be calculated (step S6).
[0025] Next, as shown in Figure 8, the control device 3 controls the support platform lifting device 2 to raise the support surface 2a to directly below the bottom surface of the article W being held by the hand 17 (step S7). The support surface 2a may be raised to a position where it contacts the bottom surface of the article W, or it may be raised to a position where it is positioned below the bottom surface of the article W with a predetermined small gap between them. Positioning the support surface 2a below the bottom surface of the article W with a small gap between them prevents the support surface 2a from colliding with the bottom surface even if the height of the bottom surface of the article W cannot be accurately calculated due to detection errors in the 3D image sensor 4.
[0026] In this state, the control device 3 synchronously controls the robot 1 and the support platform lifting device 2, and raises and lowers the article W and the support platform 21 while maintaining the relationship between the article W and the support surface 2a, as shown in Figure 9 (step S8). The example shown in the figure shows the case where the bottom surface of the article W at the loading location is lower than the height F of the top surface of the roller conveyor 300 at the unloading location. The height F of the top surface of the roller conveyor 300 is known.
[0027] Therefore, the control device 3 synchronizes the control of the robot 1 and the support base 21 to move the height of the bottom surface of the item W to the height F of the top surface of the roller conveyor 300 (step S8). Then, the control device 3 controls the robot 1 to move the item W horizontally above the roller conveyor 300 (step S9), releases the suction by the hand 17, and transfers the item W onto the roller conveyor 300 (step S10). In this way, one item W is transported from the loading area to the unloading area. If multiple items W are loaded into the loading area, the process from step S1 is repeated.
[0028] As described above, according to this embodiment, during transport by the robot 1 from the flat pallet 200, which is the loading location, to the roller conveyor 300, which is the unloading location, the support surface 2a is positioned in contact with or close to the bottom surface of the item W. As a result, even if the item W is about to fall from the hand 17 during transport due to incomplete suction by the hand 17, the support surface 2a supports the bottom surface of the item W, preventing it from falling completely. Even in an incomplete suction state, as long as the item W is supported by the support surface 2a, the robot 1 can drag the item W along the support surface 2a and transport it to the roller conveyor 300.
[0029] Furthermore, since the handle 17 does not have a mechanism to support the bottom surface of the item W, it is possible to prevent the handle 17 from becoming too large. Also, in this embodiment, a flat pallet 200 is used as the loading area, but a cage trolley may be used instead. This allows the handle 17 to be used without interfering with the item W or surrounding objects such as the cage trolley, even in narrow loading areas such as those with cage trolleys.
[0030] Furthermore, according to this embodiment, the height of the bottom surface of the item W to be transported is obtained. Therefore, even if an item W of an unknown height is brought into the loading location, or if multiple items W are stacked in multiple layers, the items W can be transported while preventing them from falling during transport.
[0031] Furthermore, according to this embodiment, the height of the bottom surface of the item W is detected using the three-dimensional image sensor 4 that detects the item W at the loading location, so there is no need to prepare a separate sensor, and the configuration can be simplified.
[0032] Furthermore, according to this embodiment, before moving the article W above the support surface 2a, the support surface 2a is positioned slightly lower than the bottom surface of the article W and as close as possible. This reduces the time required to bring the support surface 2a into contact with or close to the bottom surface of the article W in the next step, thereby shortening the cycle time.
[0033] Furthermore, according to this embodiment, by synchronously controlling the robot 1 and the support platform lifting device 2, the item W is raised and lowered while maintaining a state in which the support surface 2a is in contact with or close to the bottom surface of the item W. As a result, when moving the support surface 2a to the height F of the upper surface of the roller conveyor 300, the raising or lowering of the item W by the robot 1 and the raising or lowering of the support surface 2a can be performed simultaneously, thus enabling efficient transport.
[0034] In this embodiment, the control device 3 may detect when the support surface 2a, which has been raised based on the torque of the motor 26, collides with the bottom surface of the article W, and control the support surface 2a so as not to apply excessive force to it.
[0035] In this embodiment, a height information acquisition means is configured to acquire height information of the bottom surface of the item W using a three-dimensional image sensor 4 positioned vertically above the loading area. Alternatively, a height information acquisition means may be configured using one or more sensors (not shown) that have light-emitting and light-receiving units positioned at both ends in the width direction of the support surface 2a, forming a beam that extends parallel to the support surface 2a slightly above the support surface 2a.
[0036] In this case, instead of steps S5 to S7 in Figure 3, steps S11 to S13 may be used as shown in Figure 10. That is, the control device 3 controls the robot 1 to position the item W picked up by the hand 17 above the support surface 2a, and then controls the support base lifting device 2 to raise the support base 21 (step S11). Then, it determines whether the sensor has detected the bottom surface of the item W based on whether the sensor beam is blocked by the item W (step S12), and if it has not detected it, it repeats the process from step S11. If it has detected it, the control device 3 controls the support base lifting device 2 to stop the support base 21 from rising (step S13).
[0037] Since the sensor directly detects the bottom surface of the item W, the support surface 2a can be brought into contact with or close to the bottom surface of the item W more easily and accurately.
[0038] Alternatively, instead of one or more sensors forming a beam, a distance sensor 5 having an upward-facing optical axis may be placed at the end of the support base 21, as shown in Figure 11, slightly above the support surface 2a. In this case, steps S14 to S16 may be used instead of steps S4 to S6 in Figure 3, as shown in Figure 12. That is, the control device 3 controls the robot 1 to move the object W picked up by the hand 17 vertically upward to expose the bottom surface of the object W (step S14).
[0039] In this state, the distance sensor 5 detects the distance to the bottom surface of the item W (step S15). After this, the control device 3 controls the robot 1 and the support stand lifting device 2 based on the distance detected by the distance sensor 5 to move the item W above the support surface 2a (step S16). At this time, the item W can be moved directly to a position where its bottom surface is in contact with the support surface 2a or is close to it with a small gap (step S7). In this example, since the item W is raised and transferred to the roller conveyor 300 in the next step S8, it is preferable to raise both the item W and the support stand 21 while bringing the bottom surface of the item W into contact with or close to the support surface 2a.
[0040] Alternatively, instead of the distance sensor 5, as shown in Figure 13, a photoelectric sensor (optical sensor) 6 having a beam extending in the longitudinal direction of the support base 21 (in the direction perpendicular to the plane of the paper in Figure 13) may be placed on the edge of the support base 21 slightly above the loading area. In this example, as shown in Figure 14, the item W held by the hand 17 is dragged without being lifted until only a portion of the bottom surface of the item W is positioned vertically above the support surface 2a.
[0041] Since the shape of the top surface of the object W to be picked up is detected by the 3D image sensor 4, the horizontal center of gravity O of the object W can also be calculated. When moving the object W so that only a portion of its bottom surface is exposed, as shown in Figure 14, it is moved by an amount that does not cause the center of gravity O to exceed the edge of the object W below. This allows the object W to be picked up to be supported and transported more stably.
[0042] In this state, as shown in FIG. 15, the support base 21 is raised, and the support base 21 is stopped at a position where the beam is blocked by the bottom surface of the article W, so that the support surface 2a can be arranged at a position close to the bottom surface of the article W. Then, by controlling the robot 1 to further slide the article W toward the robot 1 side, the entire article W can be arranged above the support surface 2a.
[0043] By configuring in this way, the distance between the bottom surface of the article W and the support surface 2a during the conveyance of the article W can be minimized, and the fall of the article W can be more reliably prevented.
[0044] Also, in the present embodiment, instead of the photoelectric sensor 6, an area sensor that forms a sheet-like beam parallel to the support surface 2a may be arranged slightly above the support surface 2a. Then, when the support surface 2a is raised to directly below the bottom surface of the article W adsorbed by the hand 17, the raising of the support surface 2a may be stopped at the moment when the beam of the area sensor is blocked by the article W. By detecting the proximity of the bottom surface of the article W to the support surface 2a, it is possible to prevent the support surface 2a from colliding with the bottom surface of the article W.
[0045] Also, in the present embodiment, the support surface 2a of the support base 21 is assumed to be substantially horizontal, but instead, as shown in FIG. 16, it may be inclined so as to descend toward the tip in the length direction. By inclining the support surface 2a, a moving mechanism is configured.
[0046] In this case, the control device 3 may control the robot 1 and the support base lifting device 2 to release the adsorption of the article W by the hand 17 at a position where the support surface 2a contacts or approaches the bottom surface of the article W. The article W is transferred from the hand 17 onto the support surface 2a and moves in the length direction along the inclination by gravity and is conveyed to the roller conveyor 300.
[0047] Also, in this case, it is preferable that means for reducing friction with the placed article W is provided on the support surface 2a. Examples of the means for reducing friction include coating the support surface 2a with a low-friction material such as tetrafluoroethylene. Further, the support surface 2a may be constituted by rollers or balls, or air may be jetted from a plurality of fine holes provided in the support surface 2a.
[0048] Further, instead of inclining the support surface 2a and moving the article W in the length direction of the support surface 2a by gravity, the support base 21 may be constituted by a conveyor mechanism (transfer mechanism). The adsorption of the article W by the hand 17 can be released, and the article W transferred onto the support surface 2a can be conveyed to the roller conveyor 300 by the operation of the conveyor mechanism.
[0049] Also, as shown in FIG. 17, the support base 21 may be connected to the slider 25 by a hinge 29 so as to be rotatable about a horizontal axis. That is, the support base 21 can displace the tip in the length direction upward from the state of being supported by the slider 25 in a horizontally cantilevered beam shape. Thereby, when the support base 21 is lowered, if there is an obstacle below the support base 21, the tip of the support base 21 can be displaced upward to reduce the impact on the obstacle.
[0050] Also, in the present embodiment, one end in the length direction of the support base 21 is fixed to the slider 25. However, as shown in FIG. 18, one end in the width direction of the support base 21 may be fixed to the slider 25 at an intermediate position in the length direction of the support base 21. Thereby, the unloading places can be arranged on both sides in the length direction of the support base 21, and the article W can be conveyed. For example, when the quality of the article W can be determined during conveyance, the good products may be conveyed to one unloading place and the defective products may be conveyed to the other unloading place.
[0051] Furthermore, in this embodiment, a flat pallet 200 is used as the loading area and a roller conveyor 300 as the unloading area, but the invention is not limited to these. Any loading and unloading area such as a cage trolley, flat pallet, belt conveyor, or roller conveyor may be used. In addition, since the height of the support base 21 can be changed by the support base lifting device 2, two or more unloading areas with different heights may be provided.
[0052] Furthermore, while a single-axis linear motion mechanism was exemplified as the support platform lifting device 2, any mechanism capable of raising and lowering the support surface 2a, such as a multi-axis robot, may be used. Also, while the example shows the base 11 of the robot 1 and the base 22 of the support platform lifting device 2 being installed on the floor, the invention is not limited to this, and the base 22 of the support platform lifting device 2 may be attached to the base 11 of the robot 1. It may also be attached to a location other than the base 11 of the robot 1 (for example, the slewing cylinder 12, the first arm 13, or the second arm 14).
[0053] In this embodiment, the robot 1 and the support platform lifting device 2 are controlled in synchronous manner to raise and lower the article W while maintaining a state in which the support surface 2a is in contact with or close to the bottom surface of the article W. Alternatively, as shown in Figure 19, after step S7 in which the support surface 2a is raised to directly below the bottom surface of the article W, it may be determined whether the height F of the upper surface of the roller conveyor 300 is higher than the height B of the support surface 2a (step S31).
[0054] If height F is higher than height B, the robot 1 starts raising the item W, then starts raising the support base 21, moving the item W to height F (step S32). On the other hand, if height F is less than or equal to height B, the support base 21 starts descending, then the robot 1 starts descending the item W, moving the item W to height F (step S33). By setting the lifting speeds of the robot 1 and the support base 21 to be approximately the same, the item W can be raised and lowered while keeping the support surface 2a close to the bottom surface of the item W, without synchronizing the robot 1 and the support base 21.
[0055] Alternatively, as shown in Figure 20, after determining whether height F is higher than height B (step S31) in the same manner as in Figure 19, the robot 1 and the support base 21 may be raised and lowered in the reverse order of Figure 19. That is, if it is determined in step S31 that height F is higher than height B, the support base 21 located below is made to start rising before the robot 1 (step S34).
[0056] As a result, the support surface 2a of the support base 21 comes into contact with the bottom surface of the item W and presses it upward, so that force acts on the robot 1 and increases the torque of the robot 1's motor. The robot 1 follows suit and starts moving in a direction that reduces the torque, and continues moving until the support surface 2a is positioned at height F (step S35).
[0057] On the other hand, in step S34, if it is determined that height F is less than or equal to height B, the robot 1 positioned above is made to start descending before the support base 21 (step S36). As a result, the bottom surface of the item W comes into contact with the support surface 2a and presses it downward, and this force acts on the support base 21, increasing the torque of the motor 26 of the support base lifting device 2. The support base 21 follows suit and starts moving in a direction that reduces the torque, and continues moving until the support surface 2a is positioned at height F (step S37). This also allows the item W to be raised and lowered while keeping the support surface 2a close to the bottom surface of the item W, without synchronizing the robot 1 and the support base lifting device 2.
[0058] Furthermore, in this embodiment, a support platform lifting device 2 that supports the article W from the bottom surface is used, but instead, a device that supports the article W from the side by suction or the like may be used.
[0059] While embodiments and modifications of the present disclosure have been described above, the article transport system 100 of the present disclosure is not limited to the embodiments and modifications described above, and various modifications are possible without departing from the spirit of the present disclosure.
[0060] The following additional information is disclosed with respect to the above embodiments and modifications. (Addendum 1) An article transport system comprising: a robot installed on a surface to be installed, which picks up articles brought into a loading area with a hand attached to its tip; a support base moving device equipped with a support base that is movable relative to the surface to be installed; and a control device that controls the robot and the support base moving device to move the articles from the loading area to the loading area.
[0061] (Note 2) The article transport system according to Note 1, comprising height information acquisition means for acquiring height information of the bottom surface of the article to be picked up by the hand, wherein the control device controls the robot and the support base moving device to move the article from the loading location to the unloading location, while bringing the support surface of the support base into contact with or close to the bottom surface of the picked up article, based on the height information acquired by the height information acquisition means.
[0062] (Note 3) The article transport system according to Note 2, wherein the control device synchronously controls the robot and the support base moving device so as to move the article while maintaining the bottom surface of the article and the support surface in contact or in close proximity with a predetermined distance between them.
[0063] (Note 4) The article transport system according to Note 2, wherein the control device controls the movement of the support base moving device or the robot in a direction that reduces the force that the support surface or the robot receives from the outside in the vertical direction.
[0064] (Note 5) The article transport system according to any one of Notes 2 to 4, wherein the control device controls the support base moving device so that, when the maximum height of the article is known, the bottom surface of the article picked up by the hand does not come into contact with the support surface and waits in a close position.
[0065] (Note 5) The article transport system according to any one of Notes 2 to 5, wherein the support base moving device includes a moving mechanism for moving the article placed on the support surface toward the transport location, and the control device controls the robot and the support base moving device to bring the bottom surface of the article into contact with or close to the support surface, and then controls the robot to release the article that was being held by the hand.
[0066] (Note 7) The article transport system according to Note 6, wherein the moving mechanism is a conveyor mechanism for transporting the article mounted on the support surface.
[0067] (Note 8) The article transport system according to Note 6, wherein the moving mechanism is configured by inclining the support surface so that it becomes lower toward the unloading location.
[0068] (Note 9) The article transport system according to any one of Notes 2 to 5, wherein the support surface is provided with means for reducing friction between it and the article placed on it, and the control device controls the robot and the support base moving device to bring the bottom surface of the article into contact with the support surface, and then controls the robot to move the article toward the discharge location.
[0069] (Note 10) The article transport system according to any one of Notes 2 to 9, wherein the support base moving device comprises a slider that can be raised and lowered, and the support base is connected to the slider by a hinge in a cantilevered manner and so that its tip can be displaced upward when subjected to an external force from below.
[0070] (Note 11) The article transport system according to any one of Notes 2 to 110, wherein the height information acquisition means is a three-dimensional image sensor positioned above the loading location and acquiring height information of the article at the loading location, and the height information of the bottom surface of the article is acquired based on the height information of the top surface of the article before it is picked up by the robot and the height information of the surface on which the article was placed after it is picked up.
[0071] (Note 12) The article transport system according to any one of Notes 2 to 10, wherein the height information acquisition means is a distance sensor provided on the support base for detecting the distance from the support surface to the bottom surface of the article.
[0072] (Note 13) The article transport system according to any one of Notes 2 to 10, wherein the height information acquisition means is a sensor provided on the support base that detects the proximity of the bottom surface of the article to the support surface.
[0073] (Note 14) The article transport system according to Note 13, wherein the sensor is an area sensor that forms a sheet-like beam parallel to the support surface slightly above the support surface, and the proximity of the bottom surface of the article to the support surface is detected when the beam of the area sensor is shielded by the article.
[0074] (Note 15) The article transport system according to Note 13, wherein the sensor is an optical sensor that forms one or more linear beams slightly above the support surface, and the proximity of the bottom surface of the article to the support surface is detected when the beam of the optical sensor is shielded by the article.
[0075] (Note 16) An article transport system according to any one of Notes 2 to 10, comprising a motor that drives the support base so as to be able to move up and down, wherein the height information acquisition means detects the torque of the motor and detects contact of the bottom surface of the article with the support surface based on the detected torque.
[0076] 1 Robot 2 Support platform lifting device (support platform moving device) 2a Support surface 3 Control device 4 3D image sensor (height information acquisition means) 5 Distance sensor (height information acquisition means) 17 Hand 21 Support platform 25 Slider 29 Hinge 100 Item transport system W Item
Claims
1. An article transport system comprising: a robot installed on a surface to be installed, which picks up articles brought into an entry point using a hand attached to its tip; a support base moving device equipped with a support base that is movable relative to the surface to be installed; and a control device that controls the robot and the support base moving device to move the articles from the entry point to the output point.
2. The article transport system according to claim 1, comprising height information acquisition means for acquiring height information of the bottom surface of the article to be picked up by the hand, wherein the control device controls the robot and the support base moving device to move the article from the loading location to the unloading location, while bringing the support surface of the support base into contact with or close to the bottom surface of the picked up article, based on the height information acquired by the height information acquisition means.
3. The article transport system according to claim 2, wherein the control device synchronously controls the robot and the support base moving device to move the article while maintaining the bottom surface of the article and the support surface in contact or in close proximity with a predetermined distance between them.
4. The article transport system according to claim 2, wherein the control device controls the movement of the support base moving device or the robot in a direction that reduces the force that the support surface or the robot receives from the outside in the vertical direction.
5. The article transport system according to any one of claims 2 to 4, wherein the control device controls the support base moving device so that, when the maximum height of the article is known, the bottom surface of the article picked up by the hand does not come into contact with the support surface and remains in a position close to it.
6. The article transport system according to any one of claims 2 to 5, wherein the support base moving device comprises a moving mechanism for moving the article placed on the support surface toward the transport location, and the control device controls the robot and the support base moving device to bring the bottom surface of the article into contact with or close to the support surface, and then controls the robot to release the article that was being held by the hand.
7. The article transport system according to claim 6, wherein the moving mechanism is a conveyor mechanism for transporting the article mounted on the support surface.
8. The article transport system according to claim 6, wherein the moving mechanism is configured to incline the support surface so that it becomes lower toward the unloading location.
9. The article transport system according to any one of claims 2 to 5, wherein the support surface is provided with means for reducing friction between it and the article placed on it, and the control device controls the robot and the support base moving device to bring the bottom surface of the article into contact with the support surface, and then controls the robot to move the article toward the discharge location.
10. The article transport system according to any one of claims 2 to 9, wherein the support base moving device comprises a slider that can be raised and lowered, and the support base is connected to the slider by a hinge in a cantilevered manner and so that its tip can be displaced upward when subjected to an external force from below.
11. The article transport system according to any one of claims 2 to 10, wherein the height information acquisition means is a three-dimensional image sensor positioned above the loading location and acquiring height information of the article at the loading location, and the height information of the bottom surface of the article is acquired based on the height information of the top surface of the article before it is picked up by the robot and the height information of the surface on which the article was placed after it is picked up.
12. The article transport system according to any one of claims 2 to 10, wherein the height information acquisition means is a distance sensor provided on the support base for detecting the distance from the support surface to the bottom surface of the article.
13. The article transport system according to any one of claims 2 to 10, wherein the height information acquisition means is a sensor provided on the support base for detecting the proximity of the bottom surface of the article to the support surface.
14. The article transport system according to claim 13, wherein the sensor is an area sensor that forms a sheet-like beam parallel to the support surface slightly above the support surface, and the proximity of the bottom surface of the article to the support surface is detected when the beam of the area sensor is shielded by the article.
15. The article transport system according to claim 13, wherein the sensor is an optical sensor that forms one or more linear beams slightly above the support surface, and the proximity of the bottom surface of the article to the support surface is detected when the beam of the optical sensor is shielded by the article.
16. The article transport system according to any one of claims 2 to 10, comprising a motor that drives the support base so as to be able to move up and down, wherein the height information acquisition means detects the torque of the motor and detects contact of the bottom surface of the article with the support surface based on the detected torque.