Robot system and workpiece transfer method using transfer robot

Abstract

To enable a conveyance robot to accurately estimate its own position.SOLUTION: The robot system 1 includes a robot (work robot 2) installed in the work area 13, a transfer robot (AMR6) that transfers a workpiece (body 11) to the work area and stops by autonomously traveling while estimating its own position using the map 661 and a sensor (scanner 65), and an object (71, 72) that is detected by the sensor and included as a wall in the map and is located between the robot and the transfer robot in the work area both when the transfer robot creates a map using the sensor and when the transfer robot transfers a workpiece using the map and the sensor.SELECTED DRAWING: Figure 8

Description

[Technical Field]

[0001] The technology disclosed herein relates to a robot system and a method for transporting a workpiece using a transport robot. [Background technology]

[0002] Patent Document 1 describes a conventional robot system. The conventional robot system is used in an assembly line for automobile bodies. The conventional robot system includes a multi-axis robot. The multi-axis robot performs body welding. The conventional robot system also includes an AGV (Automatic Guided Vehicle). The AGV carries the body into an assembly area by traveling along a magnetic tape on the floor. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Patent No. 6887738 Summary of the Invention [Problem to be solved by the invention]

[0004] Instead of AGVs, it is conceivable that autonomous mobile robots (AMRs) will transport workpieces. AMRs have SLAM (Simultaneous Localization and Mapping) functionality, which allows AMRs to navigate autonomously using maps and sensors. The use of AMRs eliminates the need for magnetic tape on the floor.

[0005] AMRs create maps. As they travel through factory buildings, AMRs create maps by detecting walls with sensors. Here, a wall refers to an object on the map that indicates the boundary of the area within which the AMR can travel. Walls are not limited to structural walls of the building. While transporting a workpiece, the AMR estimates its own position by comparing the position of walls detected by the sensor with the map.

[0006] When an AMR creates a map, a robot that performs work on a workpiece is often installed inside the building. However, when creating the map, the AMR's sensors do not necessarily detect the robot as a wall, and the robot is not necessarily included in the map. Also, because the robot moves when performing work on the workpiece, even if the robot is included in the map as a wall, there is a risk that the robot's position detected by the AMR's sensors will differ from the robot's position on the map. The robot itself is difficult to use to estimate the AMR's self-location.

[0007] On the other hand, when an AMR transports a workpiece, its sensors may be unable to detect, or have difficulty detecting, walls included in the map due to being blocked by robots installed in the work area. If the sensors are unable to detect walls, the accuracy of the AMR's self-location estimation may decrease. AMRs are particularly keen to stop at precise positions in the work area, as the workpiece must be positioned correctly relative to the robot in the work area. High accuracy is required for estimating the AMR's self-location in the work area. However, as multiple robots are installed in the work area, it becomes even more difficult for the AMR's sensors to detect walls. [Means for solving the problem]

[0008] The technology disclosed herein relates to a robot system. a robot installed in a work area where work is performed on the workpiece; a transport robot that has a map of a specific area including the work area and a sensor that detects a surrounding situation, and that transports the work to the work area by autonomously traveling in the specific area while estimating its own position using the map and the sensor, and that stops in the work area until the work on the work is completed; an object that is detected by the sensor and included as a wall in the map both when the transport robot creates the map of the specific area using the sensor and when the transport robot transports the workpiece using the map and the sensor, and that is located between the robot and the transport robot in the work area; Equipped with. [Effects of the Invention]

[0009] In the robot system, the transport robot's sensor detects objects in the work area, which are included as walls on the map, allowing the transport robot to accurately estimate its own position. [Brief explanation of the drawings]

[0010] [Figure 1] Figure 1 shows part of an automobile manufacturing plant where a robot system has been installed. [Figure 2] FIG. 2 is a perspective view of the work area. [Figure 3] FIG. 3 is a rear view of the work area. [Figure 4] FIG. 4 is a block diagram of the robot system. [Figure 5] FIG. 5 is a block diagram of the AMR. [Figure 6] FIG. 6 is a perspective view of the locator with the first object attached. [Figure 7] FIG. 7 is a perspective view of the locator with a second object attached. [Figure 8] FIG. 8 is a plan view showing the arrangement of objects in the first working area and the arrangement of objects in the second working area. [Figure 9]FIG. 9 is a flowchart relating to the control of the AMR. DETAILED DESCRIPTION OF THE INVENTION

[0011] Hereinafter, an embodiment of a robot system and a method for transporting a workpiece using a robot will be described with reference to the drawings. The robot system and the method for transporting a workpiece described here are merely examples.

[0012] (Overall structure of the robot system) Fig. 1 shows a part of an automobile manufacturing plant to which a robot system 1 is applied. Fig. 2 shows an example of a work area 13 in the manufacturing plant where work is performed on a workpiece. Fig. 3 shows the work area 13 from a different angle than that shown in Fig. 2.

[0013] A manufacturing line 10 is installed in a building 12 of a manufacturing plant. The inside of the building 12 is an example of a specific area. The illustrated manufacturing line 10 is a line where welding, more specifically spot welding, is performed on an automobile body 11. The body 11 is the workpiece.

[0014] A robot system 1 is installed in the manufacturing line 10. The robot system 1 includes an autonomous mobile transport robot (AMR) 6, which will be described later. In the manufacturing line 10, a body 11 is transported by the AMR 6. A working area 13 refers to an area where a workpiece transported by the AMR 6 stays to receive work. The working area 13 is part of the manufacturing line 10. The manufacturing line 10 in the illustration has a first working area 131 and a second working area 132. The first working area 131 is located relatively upstream in the direction of travel of the AMR 6, and the second working area 132 is located relatively downstream in the direction of travel of the AMR 6. The number of working areas 13 included in the manufacturing line 10 is not limited to a specific number.

[0015] The front Fr, rear Rr, right Rt, left Lt, top Up, and bottom Lw of the robot system 1 are defined as follows, with the body 11 of the work target in the work area 13 as the reference.

[0016] The front Fr of the robot system 1 is the left rear side in the direction connecting the right front and left rear of the paper in Figure 2. The front Fr of the robot system 1 corresponds to the front of the automobile body 11, and the rear Rr of the robot system 1 corresponds to the rear of the automobile body 11. As will be described later, the front-to-rear direction corresponds to the conveyance direction of the body 11.

[0017] The right side Rt of the robot system 1 is the far right side in the direction connecting the front left and rear right of the paper in Figure 2. The right side Rt of the robot system 1 corresponds to the right side of the automobile body 11. The left side Lt of the robot system 1 corresponds to the left side of the automobile body 11. The left-right direction is a direction that is horizontally perpendicular to the front-rear direction.

[0018] The top (Up) of the robot system 1 is the top side of the paper in Fig. 2, and the bottom (Lw) of the robot system 1 is the bottom side of the paper. The top and bottom of the robot system 1 correspond to the top and bottom of the automobile body 11. The up-down direction is a direction perpendicular to the front-rear direction.

[0019] The above definitions are used to explain the robot system 1, and are not used to limit the structure or configuration of the robot system 1 and the elements included in the robot system 1 disclosed herein.

[0020] 2 or 3, robots 2 and 4 are installed in the work area 13. The robots 2 and 4 perform spot welding on the body 11 in the work area 13.

[0021] The robot 2 is a working robot 2 that performs work on a workpiece transported to the work area 13. The work that the working robot 2 performs on the body 11 is welding.

[0022] The working robot 2 is a vertical articulated robot having five to seven axes. As shown in Figure 3, the working robot 2 has a welding gun 21 as an end effector. However, the working robot 2 is not limited to a vertical articulated robot.

[0023] A plurality of work robots 2 are installed in the work area 13. The plurality of work robots 2 are positioned on either side of the automobile body 11. On the right side of the body 11, the plurality of work robots 2 are lined up in the fore-and-aft direction of the body 11. Similarly, on the left side of the body 11, the plurality of work robots 2 are lined up in the fore-and-aft direction of the body 11. Each work robot 2 performs welding at a different location on the body 11. The number of work robots 2 is not limited to a specific number. Furthermore, the arrangement of the work robots 2 is not limited to a specific arrangement.

[0024] The robot 4 is a locator 4 that serves as a support robot. Multiple locators 4 are installed in the work area 13. The multiple locators 4 are located on either side of the body 11. The locators 4 are located between the work robot 2 and the AMR 6. Note that the relative positions of the work robot 2, locator 4, and AMR 6 in the work area 13 are not limited to the example in FIG. 3.

[0025] As shown by the dashed dotted line in Figure 3, the locator 4 lifts and supports the body 11 while the work robot 2 is working. The locator 4 in the illustration is a three-axis Cartesian robot. The locator 4 has a rod 45 that engages with the body 11. The rod 45 extends horizontally. The tip of the rod 45 engages with the body 11. The locator 4 changes the position of the tip of the rod 45 back and forth, left and right, and up and down. The structure of the locator 4 will be described later.

[0026] The robot system 1 includes one or more AMRs 6. The AMRs 6 transport workpieces to a work area 13. The AMRs 6 travel on a flat floor in a factory. The path 15 of the AMRs 6 is not predetermined, but the approximate path is determined as shown by the two-dot chain line in FIG. 1.

[0027] As shown in FIG. 3, the body 11 is placed on a bogie 14. The AMR 6 is located below the bogie 14 and engages with the bogie 14. The AMR 6 transports the body 11 via the bogie 14. Note that the AMR 6 may directly support the body 11 without using the bogie 14. The AMR 6 has a substantially flat upper surface and a low height that allows it to be positioned below the bogie 14. Note that the appearance of the AMR 6 shown in FIG. 2 or 3 is an example. The structure of the AMR 6 will be described later.

[0028] 4 is a block diagram of the robot system 1. The robot system 1 includes a system controller 16. The system controller 16 controls the entire robot system 1. However, the system controller 16 is not an essential element of the robot system 1.

[0029] The robot system 1 includes a robot controller 17. Note that the robot controller 17 is not an essential element of the robot system 1. The robot controller 17 is electrically connected to the system controller 16. The electrical connection includes a wired or wireless connection. The robot controller 17 is also electrically connected to the work robot 2. The robot controller 17 and the work robot 2 are connected in a one-to-one relationship. The robot system 1 includes the same number of robot controllers 17 as the number of work robots 2.

[0030] The robot controller 17 controls the work robot 2. More specifically, the robot controller 17 receives a control signal from the system controller 16 and outputs a control signal to the work robot 2. The work robot 2 receives the control signal from the robot controller 17 and performs welding work on the body 11 in this example.

[0031] The robot system 1 includes a locator controller 18. Note that the locator controller 18 is not an essential element of the robot system 1. The locator controller 18 is electrically connected to the system controller 16. The electrical connection may be a wired or wireless connection. The locator controller 18 is also electrically connected to the multiple locators 4.

[0032] The locator controller 18 controls the locator 4. More specifically, the locator controller 18 receives a control signal from the system controller 16 and outputs a control signal to the locator 4. The locator 4 receives the control signal from the locator controller 18 and positions and supports the body 11 delivered from the AMR 6 at a predetermined position.

[0033] The robot system 1 includes an AMR control panel 19. Note that the AMR control panel 19 is not an essential element of the robot system 1. The AMR control panel 19 is electrically connected to the system controller 16. The electrical connection includes a wired or wireless connection. The AMR control panel 19 is also electrically connected to one or more AMRs 6.

[0034] The AMR control panel 19 controls the AMR 6. More specifically, the AMR control panel 19 receives a control signal from the system controller 16 and outputs the control signal to the AMR 6.

[0035] (AMR structure) Figure 5 shows the structure of AMR6. The structure of AMR6 in Figure 5 is an example of AMR6.

[0036] The AMR 6 has a plurality of wheels that roll on the floor surface, including two drive wheels 611 and 612 and a passive wheel 621 and a passive wheel 622.

[0037] The two drive wheels 611, 612 are independent. The AMR 6 is an independently driven transport vehicle. The drive wheel 611 is located on the left side of the midsection of the AMR 6 in the fore-and-aft direction. The drive wheel 612 is located on the right side of the midsection of the AMR 6. The rotation axes of the drive wheels 611 and 612 extend in the left-right direction and are coaxial.

[0038] Drive wheel 611 is mechanically connected to motor 631. Drive wheel 612 is mechanically connected to motor 632. Drive wheel 611 and drive wheel 612 can rotate independently of each other.

[0039] The motors 631, 632 are driven by power supplied from a battery. The battery is mounted on the AMR 6. The motors 631, 632 are driving sources for propelling the AMR 6. The driving force of the motors 631, 632 is transmitted to the drive wheels 611, 612, causing the drive wheels 611, 612 to rotate.

[0040] If the drive wheels 611 and 612 rotate in the same direction at the same rotation speed, the AMR 6 moves straight. If the drive wheels 611 and 612 rotate in the same direction at different rotation speeds, the AMR 6 changes direction. If the drive wheels 611 and 612 rotate in different directions, the AMR 6 turns on the spot, that is, rotates around a vertical axis.

[0041] The passive wheel 621 is located in the center in the left-right direction at the front end of the AMR 6. The passive wheel 622 is located in the center in the left-right direction at the rear end of the AMR 6. The passive wheels 621 and 622 can each change direction. Note that the AMR 6 may have a single passive wheel.

[0042] The AMR 6 has a scanner 65. The scanner 65 acquires information about the surroundings of the AMR 6. The scanner 65 is an example of a sensor. The scanner 65 includes, for example, a LiDAR (Light Detection And Ranging). The scanner 65 is not limited to a LiDAR. The scanners 65 are located at both the front end and the rear end of the AMR 6.

[0043] The AMR 6 has a storage 66. The storage 66 stores various data. The data stored in the storage 66 includes a map 661. The map 661 is a map of the inside of the building 12 including the production line 10. Before transporting the body 11, the AMR 6 autonomously travels inside the building 12 and creates the map 661 using the scanner 65 while traveling.

[0044] The AMR 6 has a communication circuit 67. The communication circuit 67 performs wireless communication with the AMR control panel 19. The communication circuit 67 can receive control signals from the AMR control panel 19. The communication circuit 67 can transmit, for example, position information of the AMR 6 to the AMR control panel 19.

[0045] The AMR 6 includes an AMR controller 69. The AMR controller 69 controls the AMR 6. The AMR controller 69 is electrically connected to the motors 631 and 632, the scanner 65, the storage 66, and the communication circuit 67.

[0046] During the creation of the map 661, the AMR controller 69 creates the map 661 based on the signal from the scanner 65 while outputting control signals to the motors 631 and 632 to move the AMR 6. The AMR controller 69 stores the created map 661 in the storage 66.

[0047] The AMR controller 69 receives control signals from the system controller 16 via the AMR control panel 19 and communication circuit 67, and causes the AMR 6 to perform an operation in accordance with the received control signal. The AMR 6 travels to a position specified by the system controller 16, that is, to the work area 13 of the work robot 2. When the AMR 6 travels, the AMR controller 69 sets a route 15 for the AMR 6 based on a map 661. While the AMR 6 is traveling, the AMR controller 69 estimates the AMR 6's own position based on the signal from the scanner 65 and the map 661. The AMR 6 autonomously travels to the work area 13 along the route 15, and the body 11 is transported to the work area 13.

[0048] (Locator structure) FIG. 6 is a perspective view of the locator 4. For the purpose of explaining the locator 4, the directions of the X-axis, Y-axis, and Z-axis are defined as follows. The X-axis is a horizontal axis, and corresponds to the left-right direction of the robot system 1 when the locator 4 is installed in the work area 13. The Y-axis is a horizontal axis, and is an axis perpendicular to the X-axis. The Y-axis corresponds to the front-rear direction of the robot system 1 when the locator 4 is installed in the work area 13. The Z-axis is a vertical axis, and is an axis perpendicular to the X-axis and Y-axis. The Z-axis corresponds to the up-down direction of the robot system 1 when the locator 4 is installed in the work area 13.

[0049] As described above, the locator 4 is a three-axis Cartesian robot. The rod 45 of the locator 4 supports the body 11 from below. The rod 45 extends in the direction of the X-axis.

[0050] The locator 4 has an engaging portion 46. The engaging portion 46 is located at the tip of the rod 45. The engaging portion 46 engages with the body 11.

[0051] The locator 4 has a base 47. The base 47 is fixed to the floor surface. The locator 4 has a displacement mechanism 410. The displacement mechanism 410 displaces the rod 45 in the X-axis, Y-axis, and Z-axis directions. The displacement mechanism 410 has a first stage 411, a second stage 412, and a third stage 413. The first stage 411 moves relative to the base 47 in the X-axis direction. The second stage 412 moves relative to the first stage 411 in the Y-axis direction. The third stage 413 moves relative to the second stage 412 in the Z-axis direction.

[0052] The multiple locators 4 support the body 11 handed over from the AMR 6. More specifically, after the AMR 6 stops in the work area 13, the multiple locators 4 each adjust the position of the rod 45 in the horizontal plane and engage the engagement portion 46 with the body 11. The multiple locators 4 then synchronously raise the rod 45 to lift the body 11 to a position for welding. Note that when the body 11 is welded, the body 11 moves upward away from the carriage 14. After the work by the work robot 2 is completed, the multiple locators 4 hand over the body 11 to the AMR 6. More specifically, the multiple locators 4 synchronously lower the rod 45 to lower the body 11 from the welding position to a position where it can be placed on the carriage 14. Once the handover of the body 11 to the carriage 14 is complete, the multiple locators 4 each move the rod 45 to its initial position and stop.

[0053] (Map creation using AMR) As described above, the AMR 6 autonomously travels within the building 12 and creates a map 661 using the scanner 65 while traveling. The scanner 65 detects, for example, the walls 121, 122, 123, 124, and 125 of the building 12. The walls 121, 122, 123, 124, and 125 are included in the map 661. The walls 121, 122, 123, 124, and 125 indicate the boundaries of the area in which the AMR 6 can travel. While the AMR 6 autonomously travels to transport the body 11, the AMR 6 detects the walls 121, 122, 123, 124, and 125 using the scanner 65 and compares the positions of the detected walls 121, 122, 123, 124, and 125 with the map 661 to estimate its own location.

[0054] When the AMR 6 is creating the map 661, the work robot 2 and locator 4 are often installed in the work area 13. However, there is a possibility that the conditions for the AMR controller 69 to determine that the work robot 2 and locator 4 detected by the scanner 65 are a wall on the map 661 are not met. Alternatively, even if the work robot 2 and locator 4 are included in the map 661 as a wall, the work robot 2 or locator 4 may move during transport of the body 11, causing a discrepancy between the position of the work robot 2 or locator 4 detected by the scanner 65 and the position of the work robot 2 or locator 4 on the map 661. The work robot 2 and locator 4 are unlikely to be used to estimate the AMR 6's own position. On the other hand, there are also cases when the AMR 6 is creating the map 661 and the work robot 2 and locator 4 are not installed in the work area 13. The work robot 2 and locator 4 are not included in the map 661. Not including the work robot 2 and locator 4 in the map 661 has the advantage of increasing the freedom in placing the work robot 2 and locator 4, since the map 661 does not need to be recreated even if the positions of the work robot 2 and locator 4 are changed.

[0055] However, when the AMR 6 transports the body 11, the work robot 2 or locator 4 installed in the work area 13 is positioned between the AMR 6 and the walls 121, 122, 123, 124, and 125. The light emitted by the scanner 65 of the AMR 6 may be blocked by the work robot 2 or locator 4, making it difficult or impossible for the scanner 65 to detect the walls 121, 122, 123, 124, and 125. If the scanner 65 cannot detect the walls 121, 122, 123, 124, and 125, the accuracy of the estimation of the AMR 6's own position may be reduced. The AMR 6 particularly wants to stop at an accurate position in the work area 13. This is because the body 11 must be positioned accurately relative to the work robot 2 or locator 4. High accuracy is required for estimating the AMR 6's own position in the work area 13. However, as shown in FIG. 2 or 3, since a large number of work robots 2 or locators 4 are installed in work area 13, it is difficult for scanner 65 to detect walls 121, 122, 123, 124, and 125.

[0056] The robot system 1 disclosed herein is characterized by the creation of a map 661 for the AMR 6, which improves the accuracy of estimating the self-position of the AMR 6. Specifically, as shown in Fig. 8, in the work area 13, objects 71 and 72, which are included as walls in the map 661, are located between the work robot 2 and locator 4 and the AMR 6. Note that for ease of understanding, the shapes of the work robot 2 and locator 4 are shown in a simplified form in Fig. 8.

[0057] FIG. 6 shows a first object 71. The first object 71 is attached to the locator 4. In the example of FIG. 6, the first object 71 is attached to the first stage 411. As the first stage 411 is displaced in the X-axis direction, the first object 71 moves in the X-axis direction. Note that the first object 71 is not limited to being attached to the first stage 411. The first object 71 may also be attached to the second stage 412, which is displaced in the horizontal direction. The first object 71 may also be attached to the base 47 so as not to move even when the rod 45 moves.

[0058] The first object 71 is formed of, for example, a plate. The first object 71 has surfaces 711 and 712 that reflect light from the scanner 65. The surfaces 711 and 712 are not surfaces that reflect light poorly, such as matte black surfaces. Furthermore, the surfaces 711 and 712 are not transparent. Both the surfaces 711 and 712 are flat surfaces. However, the surfaces 711 and 712 are not limited to flat surfaces.

[0059] The surfaces 711 and 712 have a size that allows the AMR 6 to determine the surfaces 711 and 712 as walls. More specifically, the surface 711 has a first height H1 and a first length L1, and the surface 712 has a first height H1 and a second length L2. The first height H1 may be, for example, 0.2 m or more. If the first height H1 is too high, there is a risk of interference with the locator 4 or the carriage 14. The first height H1 may be set based on the height of the AMR 6. The first length L1 and the second length L2 may each be, for example, 0.4 m or more.

[0060] Surfaces 711 and 712 intersect. Surfaces 711 and 712 have different angles as viewed from the AMR 6. The angles as viewed from the AMR 6 are angles based on the light emitted by the AMR 6. Surface 711 extends in the X-axis direction, and surface 712 extends in the Y-axis direction. Surfaces 711 and 712 are orthogonal to each other. More precisely, surfaces 711 and 712 intersect orthogonally, with the AMR 6 as the reference, so as to be concave away from the AMR 6. The first object 71 is L-shaped when viewed from above. The scanning light of the scanner 65, indicated by the two-dot chain arrow in FIG. 6, is emitted across surfaces 711 and 712, as indicated by the dotted arrow. The scanner 65 detects the first object 71 by observing the reflected light from surfaces 711 and 712. The scanner 65 is more likely to detect a first object 71 having intersecting surfaces 711 and 712.

[0061] FIG. 7 shows a second object 72. The second object 72 is attached to the locator 4. In the example of FIG. 7, the second object 72 is attached to the first stage 411. The second object 72 moves in the X-axis direction as the first stage 411 is displaced in the X-axis direction. Note that the second object 72 is not limited to being attached to the first stage 411. The second object 72 may also be attached to the second stage 412, which is displaced in the horizontal direction. The second object 72 may also be attached to the base 47 so as not to move even when the rod 45 moves.

[0062] The second object 72 is formed by, for example, a plate. The second object 72 has a surface 721 that reflects light from the scanner 65. The surface 721 is not a surface that reflects light poorly, such as a matte black surface. Furthermore, the surface 721 is not transparent. The surface 721 is a flat surface. However, the surface 721 is not limited to a flat surface. The surface 721 extends in the direction of the Y axis. The second object 72 is I-shaped compared to the first object 71, which is L-shaped.

[0063] The surface 721 has a size that allows the AMR 6 to determine the surface 721 as a wall. More specifically, the surface 721 has a third height H3 and a third length L3. The third height H3 may be, for example, 0.2 m or more. The third height H3 may be set based on the height of the AMR 6. The third length L3 may be, for example, 0.4 m or more.

[0064] FIG. 8 shows an example of the arrangement of objects 71, 72 in the first work area 131 and the second work area 132. The work robot 2 and the locator 4 are located on either side of the AMR 6 in the left-right direction. Objects 71, 72 are attached to each of the multiple locators 4 on the right side of the AMR 6. Objects 71, 72 are also attached to each of the multiple locators 4 on the left side of the AMR 6. Objects 71, 72 are located between the work robot 2 and the AMR 6 in the work area 131 or 132. Furthermore, objects 71, 72 do not overlap with the locator 4 when viewed from the AMR 6. The light emitted by the scanner 65 toward objects 71, 72 is not blocked by the locator 4.

[0065] In the first working area 131, the objects 71 and 72 are positioned so as to be line-symmetrical with respect to a center line extending from the front to the rear of the first working area 131. In addition, in the second working area 132, the objects 71 and 72 are positioned so as to be line-symmetrical with respect to a center line extending from the front to the rear of the second working area 132. The arrangement of the objects 71 and 72 in the first working area 131 is not limited to being line-symmetrical. The arrangement of the objects 71 and 72 in the second working area 132 is also not limited to being line-symmetrical.

[0066] The arrangement of the objects 71, 72 in the first working area 131 is different from the arrangement of the objects 71, 72 in the second working area 132. Specifically, in the first working area 131, the L-shaped first object 71 is attached to the rearmost locator 4 of the multiple locators 4 lined up in the front-to-rear direction. The I-shaped second object 72 is attached to the remaining locators 4. In the second working area 132, the L-shaped first object 71 is attached to the rearmost locator 4 and the second-to-last locator 4 of the multiple locators 4 lined up in the front-to-rear direction. The I-shaped second object 72 is attached to the remaining locators 4. Note that the arrangement of the objects 71, 72 in the first working area 131 shown in FIG. 8 is an example, and the arrangement of the objects 71, 72 in the second working area 132 is also an example.

[0067] Next, a process for creating a map 661 by the AMR 6 and a process for transporting the body 11 using the map 661 and the scanner 65 will be described. FIG. 9 is a flowchart related to the control of the AMR 6. Steps S1 to S5 in the flow of FIG. 9 are steps related to the creation of the map 661 by the AMR 6. First, in step S1, the AMR controller 69 determines whether or not to create the map 661. If the map 661 is to be created, the process of FIG. 9 proceeds to step S2. In step S2, the AMR controller 69 travels within a specific area, i.e., the factory building 12, using the scanner 65. In the subsequent step S3, the AMR controller 69 creates the map 661 based on the detection of the scanner 65. When creating the map 661, at least a locator 4 having objects 71 and 72 is installed in the work area 13. The scanner 65 detects the objects 71 and 72, and the AMR controller 69 determines that the detected objects 71 and 72 are walls. The map 661 includes objects 71 and 72. In step S4, the AMR controller 69 determines whether creation of the map 661 is complete, and if not, the AMR controller 69 repeats steps S2 and S3. If creation of the map 661 is complete, the AMR controller 69 stores the created map 661 in the storage 66 in step S5.

[0068] Steps S6 to S11 in the flow of FIG. 9 are steps related to transporting the body 11 using the created map 661. If the AMR controller 69 determines NO in step S1, the AMR controller 69 determines in step S6 whether the body 11 is being transported. If the body 11 is not being transported, the process of FIG. 9 returns to step S1. If the body 11 is being transported, the AMR controller 69 determines in step S7 whether an instruction has been received from the system controller 16. If an instruction has not been received, the process of FIG. 9 returns to step S1. If an instruction has been received, the AMR controller 69 autonomously travels to the instructed work area 13 using the map 661 and the scanner 65 in step S8. While the AMR 6 is autonomously traveling to transport the body 11, a locator 4 having objects 71 and 72 is placed in the work area 13. The scanner 65 detects objects 71 and 72, and the AMR controller 69 compares the detected objects 71 and 72 with a map 661 to estimate its own position.

[0069] In step S9, the AMR controller 69 determines whether the AMR 6 has arrived at the work area 13. The AMR 6 continues autonomous traveling until it arrives at the work area 13 (see step S8). Once the AMR 6 arrives at the work area 13, in step S10, the AMR 6 stops at a predetermined position in the work area 13. The body 11 is handed over from the AMR 6 to the locator 4.

[0070] In step S11, the AMR controller 69 determines whether the work robot 2 has completed its task. The AMR 6 remains stopped until the task is completed. If the task is completed, the process in FIG. 9 returns to step S7. The AMR controller 69 determines whether the next instruction has been received, and if an instruction has been received, steps S8 to S11 are repeated. If an instruction has not been received, the process in FIG. 9 returns to step S1.

[0071] (Action and effect) The AMR 6 does not require a running guide. As shown in Figure 2 or 3, a production line 10 equipped with the AMR 6 has the advantage of not requiring the pits required in conventional production lines for laying body transport rails and body elevators. Another advantage is that, because the floor in the factory is flat, the production line 10 equipped with the AMR 6 can easily accommodate layout changes.

[0072] Furthermore, using an AMR6 in the production line 10 enables production adjustments by adjusting the number of AMR6s, thereby realizing flexible operation of the production line 10.

[0073] When the AMR 6 creates the map 661, objects 71 and 72 are attached to the locator 4 installed in the work area 13. The scanner 65 of the AMR 6 detects the objects 71 and 72 in addition to the walls 121, 122, 123, 124, and 125, and the AMR controller 69 includes the objects 71 and 72 as walls in the map 661 in addition to the detected walls 121, 122, 123, 124, and 125. The robot system 1 can include the objects 71 and 72 in the map 661.

[0074] Even when the AMR 6 transports the body 11, objects 71 and 72 are attached to the locator 4 installed in the work area 13. The scanner 65 of the AMR 6 detects the objects 71 and 72 in addition to the walls 121, 122, 123, 124, and 125, and the AMR controller 69 estimates the self-location of the AMR 6 by comparing the detected positions of the walls 121, 122, 123, 124, and 125 and the objects 71 and 72 with the map 661. As shown in FIG. 8 , the objects 71 and 72 are located between the work robot 2 and the AMR 6. Therefore, even if the light from the scanner 65 is blocked by the work robot 2 and does not reach the walls 121, 122, 123, 124, and 125, the light from the scanner 65 can still reach the objects 71 and 72. The scanner 65 can stably detect the objects 71 and 72. Stable detection of objects 71 and 72 included in map 661 improves the accuracy of AMR6's self-location estimation.

[0075] Objects 71 and 72 are attached to the robot. More specifically, objects 71 and 72 are attached to locator 4. Objects 71 and 72 change position when locator 4 operates. Because locator 4 does not support body 11 until AMR 6 reaches work area 13 and stops, rod 45 of locator 4 is located in its initial position. The positions of objects 71 and 72 correspond to the initial position of rod 45. When creating a map for AMR 6 and when AMR 6 transports body 11, the positions of objects 71 and 72 detected by scanner 65 correspond to their initial positions. Therefore, the detected positions of objects 71 and 72 can be used to estimate the self-location of AMR 6 by comparing them with map 661. Attaching objects 71 and 72 to locator 4 allows the distance between AMR 6 and locator 4 to be narrowed, contributing to a more compact work area 13.

[0076] Furthermore, objects 71 and 72 are located on both the left and right sides of the AMR 6 in the working area 13. A large number of objects 71 and 72 improves the accuracy of estimating the self-location of the AMR 6. Furthermore, the first object 71 is L-shaped. The L-shaped first object 71, which has surfaces 711 and 712, is stably detected by the scanner 65. The L-shaped first object 71 is advantageous for improving the accuracy of estimating the self-location of the AMR 6. Furthermore, since objects 71 and 72 have light-reflecting surfaces 711, 712, and 721, the scanner 65 can stably detect the objects 71 and 72.

[0077] Because the arrangement of the objects 71, 72 in the first working area 131 is different from the arrangement of the objects 71, 72 in the second working area 132, the AMR 6 can distinguish between the first working area 131 and the second working area 132 based on the detected objects 71, 72. As illustrated in FIG. 1 , particularly in a production line 10 where multiple working areas 13 are lined up, distinguishing between the multiple working areas 13 is advantageous for improving the accuracy of estimating the AMR 6's own position.

[0078] (Variation) The objects 71 and 72 may be attached to the work robot 2 instead of being attached to the locator 4. The objects 71 and 72 may be attached to both the locator 4 and the work robot 2. Furthermore, the objects 71 and 72 may be placed between the locator 4 and the AMR 6 without being attached to the locator 4.

[0079] The shapes of the objects 71 and 72 are not limited to the examples in Figures 6 and 7. The objects 71 and 72 may have various shapes. The surface 711 may be angled with respect to the X axis, and the surface 712 may be angled with respect to the Y axis. The surface 721 may be angled with respect to the Y axis.

[0080] The objects 71 and 72 do not necessarily have to be attached to all of the locators 4. The objects 71 and 72 may be attached to some of the locators 4 in the work area 13.

[0081] Furthermore, the number of objects 71, 72 in the first working area 131 and the number of objects 71, 72 in the second working area 132 may be different.

[0082] The robot system 1 may be equipped with an articulated robot that supports the body 11 instead of or in addition to the locator 4. In other words, the support robot is not limited to being a three-axis Cartesian robot. The objects 71, 72 may be attached to the articulated robot that supports the body 11. The locator 4, which is a three-axis Cartesian robot, is relatively small. The locator 4, which is located between the AMR 6 and the work robot 2, is less likely to interfere with the work robot 2, and by narrowing the gap between the locator 4 and the work robot 2, there is an advantage that the work area 13 can be made smaller.

[0083] The system controller 16 may be omitted from the robot system 1. The robot system 1 may perform welding work on the body 11 through mutual communication between the robot controller 17, the locator controller 18, and the AMR control panel 19.

[0084] It should be noted that the work performed by the robot system 1 disclosed herein in the manufacturing line 10 is not limited to welding. Furthermore, the workpiece that the robot system 1 acts on is not limited to the automobile body 11. Furthermore, the robot system 1 is not limited to application to the automobile manufacturing line 10.

[0085] The functions of the elements disclosed herein can be performed using circuits or processing circuits, including general-purpose processors, special-purpose processors, integrated circuits, ASICs (Application Specific Integrated Circuits), conventional circuits, and / or combinations thereof, configured or programmed to perform the disclosed functions. A processor is considered a processing circuit or circuit because it includes transistors and other circuitry. In this disclosure, a circuit, unit, or means is hardware that performs the recited functions or hardware that is programmed to perform the recited functions. The hardware may be hardware disclosed herein or other known hardware that is programmed or configured to perform the recited functions. Where the hardware is a processor, which is considered a type of circuit, the circuit, means, or unit is a combination of hardware and software, and the software is used to configure the hardware and / or processor.

[0086] (Aspect) The above-described embodiments are examples of the following aspects.

[0087] (Aspect 1) a robot (2, 4) installed in a work area (13) where work is performed on a workpiece (11); a transport robot (6) having a map (661) of a specific area including the work area (13) and a sensor (65) for detecting surrounding conditions, and transporting the work (11) to the work area (13) by autonomously traveling in the specific area while estimating its own position using the map (661) and the sensor (65), and stopping in the work area (13) until work on the work (11) is completed; objects (71, 72) that are detected by the sensor (65) and included as walls in the map (611), both when the transport robot (6) creates the map (611) of the specific area using the sensor (65) and when the transport robot (6) transports the workpiece (11) using the map (611) and the sensor (65), and that are located between the robots (2, 4) and the transport robot (6) in the work area (13); A robot system (1) comprising:

[0088] When the transfer robot 6 creates a map 611, the robot system 1 can include the objects 71, 72 as walls in the map 611. Since the objects 71, 72 in the work area 13 are easily detected by the sensor 65, the robot system 1 can improve the accuracy of estimating the self-position of the transfer robot 6 by comparing the positions of the detected objects 71, 72 with the map 611 when transferring the workpiece 11.

[0089] (Aspect 2) The object (71, 72) is attached to the robot (2, 4). The robot system (1) according to embodiment 1.

[0090] Attaching the objects (71, 72) to the robots (2, 4) improves the space efficiency of the work area (13). Furthermore, when changing the layout to change the positions of the robots (2, 4), the objects (71, 72) can be placed in positions that correspond to the positions of the robots (2, 4).

[0091] (Aspect 3) In the work area (13), a work robot (2) that performs work on the workpiece (11) and a support robot (4) that supports the workpiece (11) delivered from the transport robot (6) while the work robot (2) is working are installed; The object (71, 72) is attached to the support robot (4). The robot system (1) according to aspect 1 or 2.

[0092] (Aspect 4) the working robot (2) is located to the side of the transport robot (6) in a first direction perpendicular to the traveling direction of the transport robot (6) in the work area (13); The support robot (4) is located between the work robot (2) and the transport robot (6). A robot system (1) according to embodiment 3.

[0093] By positioning the support robot (4) between the work robot (2) and the transport robot (6), the support robot (4) and the work robot (2) can be efficiently arranged in the work area (13) while avoiding interference between the support robot (4) and the work robot (2).

[0094] By attaching the objects (71, 72) to the support robot (4), the sensor (65) of the transport robot (6) can stably detect the objects (71, 72) without being blocked by the work robot (2). Stable detection of the objects (71, 72) improves the accuracy of estimating the self-position of the transport robot (6).

[0095] (Aspect 5) the working robot (2) and the support robot (4) are located on a first side and a second side of the transport robot (6) in the first direction, respectively; The object (71, 72) is attached to the support robot (4) on the first side and the support robot (4) on the second side. The robot system (1) according to aspect 3 or 4.

[0096] The objects (71, 72) located on the first and second sides of the transport robot (6) increase the number of objects (71, 72) detected by the sensor (65). The increase in the number of objects (71, 72) improves the accuracy of estimating the self-position of the transport robot (6).

[0097] (Aspect 6) The support robot (4) is a three-axis Cartesian robot. A robot system (1) according to any one of aspects 3 to 5.

[0098] Because the three-axis Cartesian robot is relatively small, the support robot (4) and the work robot (2) can be efficiently arranged in the work area (13) while avoiding interference between them. Efficient arrangement of the support robot (4) and the work robot (2) narrows the distance between the support robot (4) and the work robot (2), making it difficult for the sensor (65) to detect walls. By placing objects (71, 72) in the work area (13), the transport robot (6) can accurately estimate its own position.

[0099] (Aspect 7) The sensor (65) is a LiDAR (Light Detection And Ranging) sensor, The objects (71, 72) have surfaces (711, 712, 721) that reflect light. A robot system (1) according to any one of aspects 1 to 6.

[0100] Having surfaces (711, 712, 721) on the objects (71, 72) that reflect light emitted by the LiDAR is advantageous for stable detection of the objects (71, 72) by the sensor (65).

[0101] (Aspect 8) The first object (71) has a first surface (711) and a second surface (712), The first surface (711) and the second surface (712) are at different angles when viewed from the transport robot (6). A robot system (1) according to embodiment 7.

[0102] The sensor 65 can stably detect the first object 71 having a first surface 711 and a second surface 712 at different angles. The first object 71 improves the accuracy of estimating the self-position of the transport robot 6.

[0103] (Aspect 9) The working area (13) includes a first working area (131) and a second working area (132), The arrangement of the objects (71, 72) in the first working area (131) is different from the arrangement of the objects (71, 72) in the second working area (132). A robot system (1) according to any one of aspects 1 to 8.

[0104] If the arrangement of the objects (71, 72) in the first working area (131) differs from the arrangement of the objects (71, 72) in the second working area (132), the transfer robot (6) can distinguish between the first working area (131) and the second working area (132) based on the arrangement of the detected objects (71, 72), which is advantageous in improving the accuracy of estimating the self-position of the transfer robot (6).

[0105] (Aspect 10) The objects (71, 72) include a first object (71) and a second object (72) having a shape different from that of the first object (71). A robot system (1) according to any one of aspects 1 to 9.

[0106] When a first object (71) and a second object (72) having different shapes are combined and placed in the working area (13), the transport robot (6) can accurately estimate its own position based on the differences in the characteristics of the first object (71) and the second object (72) detected by the sensor (65).

[0107] (Aspect 11) The transport robot (6) uses a sensor (65) for detecting the surrounding conditions to create a map (661) of a specific area including a work area (13) where the robots (2, 4) are installed and where work is performed on the workpiece (11); the transport robot (6) transports the workpiece (11) to the working area (13) by autonomously traveling in the specific area while estimating its own position using the map (661) and the sensor (65); The transport robot (6) stops in the work area (13) until the work on the workpiece (11) is completed, When the transport robot (6) creates the map (661) using the sensor (65) and when the transport robot (6) transports the workpiece (11) using the map (661) and the sensor (65), an object (71, 72) detected by the sensor (65) and included as a wall in the map (661) is located between the robots (2, 4) and the transport robot (6) in the work area (13). A method for transporting a workpiece (11) using a transport robot (6).

[0108] The sensor (65) of the transport robot (6) detects the objects (71, 72) in the work area (13) that are included as walls in the map (661), allowing the transport robot (6) to accurately estimate its own position. [Explanation of symbols]

[0109] 1. Robot System 11 Body (work) 13 Work Area 131 First Work Area 132 Second Work Area 2. Work robots 4 Locator (support robot) 6 AMR (Transport Robot) 65 Scanner (sensor) 661 Map 71 Object 711 sides 712 sides 72 objects 721 sides

Claims

1. a robot installed in a work area where work is performed on the workpiece; a transport robot that has a map of a specific area including the work area and a sensor that detects a surrounding situation, and that transports the work to the work area by autonomously traveling in the specific area while estimating its own position using the map and the sensor, and that stops in the work area until the work on the work is completed; an object that is detected by the sensor and included as a wall in the map both when the transport robot creates the map of the specific area using the sensor and when the transport robot transports the workpiece using the map and the sensor, and that is located between the robot and the transport robot in the work area; Equipped with Robot system.

2. 2. The robot system according to claim 1, the object is attached to the robot; Robot system.

3. 3. The robot system according to claim 2, a work robot that performs work on the workpiece and a support robot that supports the workpiece delivered from the transport robot while the work robot is working are installed in the work area; the object is attached to the support robot; Robot system.

4. 4. The robot system according to claim 3, the working robot is positioned to the side of the transport robot in a first direction perpendicular to a traveling direction of the transport robot in the work area, the support robot is located between the work robot and the transport robot; Robot system.

5. The robot system according to claim 4, the working robot and the support robot are located on a first side and a second side of the transport robot in the first direction, the object is attached to the support robot on a first side and the support robot on a second side; Robot system.

6. 6. The robot system according to claim 3, The support robot is a three-axis Cartesian robot. Robot system.

7. 2. The robot system according to claim 1, The sensor is a LiDAR (Light Detection And Ranging) sensor, The object has a surface that reflects light. Robot system.

8. The robot system according to claim 7, the object has a first surface and a second surface; the first surface and the second surface are at different angles as seen from the transport robot; Robot system.

9. 2. The robot system according to claim 1, the work area includes a first work area and a second work area; The arrangement of the objects in the first working area is different from the arrangement of the objects in the second working area. Robot system.

10. 2. The robot system according to claim 1, The objects include a first object and a second object having a shape different from that of the first object. Robot system.

11. The transport robot uses a sensor that detects the surrounding conditions to create a map of a specific area including a work area where the robot is installed and where work is performed on the workpiece; the transport robot transports the workpiece to the work area by autonomously traveling in the specific area while estimating its own position using the map and the sensor; the transport robot stops in the work area until the work on the workpiece is completed, an object detected by the sensor and included as a wall in the map is located between the robot and the transport robot in the work area both when the transport robot creates the map using the sensor and when the transport robot transports the workpiece using the map and the sensor; A method for transporting workpieces using a transport robot.

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