Automatic guided vehicle and method

Abstract

To allow a smart automatic guided vehicle to store and retrieve inventory items according to instructions.SOLUTION: An automatic guided vehicle moves between two warehouse shelves and is configured to use a material conveying device to store one or more inventory items in any warehouse shelf or to retrieve one or more inventory items from any warehouse shelf. A shift detection device is configured to detect a position shift of the inventory item compared to a position of the inventory item obtained from a command received by the automatic guided vehicle. A drive unit is configured to drive the automatic guided vehicle on the basis of the position shift and to adjust a position of the automatic guided vehicle to compensate for the position shift.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] CROSS-REFERENCE TO RELATED APPLICATIONS This application claims priority to CN201711141498.3, filed on November 14, 2017 and entitled "Method and System for Automatically Loading and Retrieving Cargo," and CN201711135812.7, filed on November 14, 2017 and entitled "Robotics," the entire contents of which are incorporated herein by reference.

[0002] FIELD OF THE DISCLOSURE This disclosure relates generally to warehouse automation systems, and more specifically to automated guided vehicles (AGVs) and methods for transporting, storing, and retrieving inventory items in a warehouse. [Background technology]

[0003] In warehouses, machines are used to transport goods from the warehouse to the loading dock and vice versa. Machines were initially used to transport heavy or bulky items and relieve humans from hard work, but the latest developments in Artificial Intelligence (AI) and robotics have given birth to advanced machines that can replace humans in many areas, not only in industrial environments but also in daily life.

[0004] While there are many articles about advances in automation and AI, precision and agility remain two areas of robotics where humans still lag behind. In a warehouse environment, fully automated machines can take orders and go to the warehouse to pick up items from inventory and deliver them to the designated location, which is more science fiction than reality. Some known systems, for example, the KIVA system, can complete simple mechanical movements of transporting heavy shelves from one designated location to another. However, the capabilities of a fully automated system, for example, being able to pick up inventory items from designated shelves and place them in the warehouse while simultaneously navigating through a crowded warehouse full of obstacles and transporting inventory items that have already shifted to a location, are yet to be realized in a commercial warehouse robotic system. Summary of the Invention [Problem to be solved by the invention]

[0005] Thus, one objective of the present disclosure is to direct a smart automated guided vehicle to store and retrieve inventory items as directed. The AGV disclosed herein is an agile, efficient, fault tolerant system, and is particularly suited for use in warehouses filled with storage shelves. [Means for solving the problem]

[0006] In some embodiments, an automated guided vehicle (AGV) designed for storing or retrieving inventory items is disclosed that includes a drive unit, a multi-layer framework, and a material handling device. The drive unit is configured to drive the AGV. In some embodiments, the drive unit may include a motor and one or more drive wheels. In some embodiments, the multi-layer framework includes one or more storage plates for storing one or more inventory items. The multi-layer framework further includes a lifting device for raising and lowering the material handling device. The material handling device includes a tray, an extendable device, and a lateral device. The tray is configured to store the inventory items. The extendable device is connected to the tray and configured to be extendable and retractable. The lateral device is configured to move the tray to the right or left. As the extendable device extends, the extendable device reaches inside the shelf to place an item on the shelf or retrieve an item from the shelf. In one embodiment, when the extendable device retracts, the lateral device returns to its original position. In another embodiment, the lateral device can return with one inventory item retrieved from a shelf and place said inventory item in one storage plate of the multi-tiered framework. The AGV is configured to travel between two warehouse shelves and use the material handling device to store inventory items on any shelf or retrieve inventory items from any shelf.

[0007] In some embodiments, the multi-layer framework is attached to the drive unit, and the multi-layer framework includes support columns for accommodating the lifting device. The lifting device may be configured to move along the support columns and to stop at each layer of the multi-layer framework. The lifting device may be configured to raise and lower the material transport device to a certain height for storing or removing an inventory item from a warehouse shelf. The height may be determined based on a position of the inventory item. The height may further be determined based on a position of one of the storage plates on the multi-layer framework. When the material transport device is raised and lowered to the height of the storage plate, the material transport device is configured to place the inventory item on the storage plate by contracting the extendable device or remove the inventory item from the shelf by extending the extendable device. In some embodiments, the extendable device can be extended to two or more positions. In one embodiment, the lateral direction device of the material transport device is configured to rotate the tray 90° to the right or left. In another embodiment, the lateral direction device of the material transport device is configured to translate the tray to the right or left. In some embodiments, the material transport device is configured to rotate 90 degrees and then extend to a second position to reach an interior portion of the shelf.

[0008] In some embodiments, the AGV further includes a transceiver for sending instructions to and receiving instructions from the warehouse server, and a processor configured to control the AGV. The transceiver is configured to receive instructions to transport the inventory item. The processor is configured to parse the instructions to obtain a position of the inventory item. In one embodiment, the position of the inventory item includes an x ​​coordinate, a y coordinate, an orientation and a height of the inventory item.

[0009] In some embodiments, the AGV includes a navigation unit configured to detect obstacles and determine a path of travel for the AGV based on the positions of the inventory items. The navigation unit may be further configured to read navigation signs posted inside the warehouse for navigation purposes. Illustrative examples of navigation signs may include bar codes, two-dimensional bar codes, and other identification codes.

[0010] In one embodiment, when the AGV navigates toward the inventory position, the processor is configured to command the material handling device to move to a specified height of the inventory position before the AGV reaches the inventory position.

[0011] In one embodiment, when the AGV reaches the inventory position, the extendable device of the material handling device extends the tray to reach the inventory. In one embodiment, the tray is configured to grip the inventory item to move the inventory item onto or off of the tray. In another embodiment, the tray is configured to slide underneath the inventory item to raise or lower the inventory item. The tray may further include some mechanism to push or pull the inventory item. For example, the tray may be equipped with a mechanical boom or fork that can open or fold to grip, pull, or lift the item.

[0012] In some embodiments, the AGV further includes a shift detection device configured to detect a position shift of the inventory item compared to a position obtained by an instruction received from the AGV. Based on the position shift, the processor is configured to adjust a position of the AGV or a position of the material handling device to enable the material handling device to reach and transport the inventory item. The shift detection device can use one or more of a laser device, a radar device, a lighting device, a barcode reader, and a pattern recognition device to detect the position shift.

[0013] In some embodiments, an automated guided vehicle (AGV) system for storing or retrieving inventory items in a warehouse may include a drive unit configured to drive the AGV, a multi-layer framework including one or more storage plates for storing one or more inventory items, and a lifting device. The AGV may further include a material handling device, a transceiver, and one or more processors. The material handling device may further include a tray, an extendable device, and a lateral device. The tray is for storing the inventory items. The lateral device is configured to move the tray laterally to the right or left side of the AGV system. The extendable device is configured to extend or retract perpendicular to the lateral direction. In some embodiments, the lateral device rotates the tray to the left or right. In some embodiments, the lateral device translates the tray parallel to the left or right. The transceiver is configured to communicate with a warehouse server, and the one or more processors are configured to control the AGV. The AGV system is configured to navigate between and laterally reach storage shelves within a warehouse. The lifting device of the multi-layer framework is configured to move the material conveying device vertically and stop at each layer of the multi-layer framework or at a specified height. In one embodiment, the lateral direction device of the material conveying device is configured to rotate the lifting device 90° to the right or left.

[0014] In some embodiments, the transceiver is configured to receive an instruction to transport an inventory item, and the one or more processors are configured to derive a position of the inventory item from the received instruction.

[0015] In some embodiments, the AGV system may further include a shift detection device for detecting a position shift of the inventory item. The one or more processors are configured to adjust a position of the AGV and a position of the lifting device based on the position shift to allow the material device to reach and transport the inventory item. The shift detection device may use one or more of the following devices to detect the position shift: a laser device, a radar device, a lighting device, a barcode reader, and a pattern recognition device.

[0016] The present disclosure further discloses a method for controlling a warehouse robot to store or retrieve an inventory item from a shelf. The method includes the following steps: First, the warehouse robot receives an instruction to transport an inventory item. The robot obtains a position of the inventory item from the received instruction. The position of the inventory item includes a location of the inventory item and an orientation of the inventory item. After analyzing the instruction, the warehouse robot moves to the location of the inventory item. Before reaching the inventory item, the warehouse robot can try and detect a position shift of the inventory item from the obtained position. The position shift can include a position deviation and / or a change in orientation and / or a height deviation of the inventory item. In some embodiments, the processor is configured to report the position shift to a server. If a position shift occurs, the warehouse robot adjusts its position and / or a position of a material handling device. In some embodiments, the warehouse robot can adjust itself to compensate for the shift in orientation and / or position and / or height of the inventory item. After compensating for the position shift, the warehouse robot reaches the inventory item and retrieves the inventory item from the storage shelf. The warehouse robot then transports the inventory item to its destination. When the warehouse robot reaches inside the shelf to place or remove the inventory item, the lateral direction device of the material transport device moves along the lateral direction, so that the warehouse robot does not need to turn around to face the shelf before reaching the inventory item.

[0017] In some embodiments, adjusting the position of the warehouse robot to compensate for the position includes comparing the position shift to a threshold, adjusting the position of the warehouse robot based on the position shift if the position shift is greater than the threshold, measuring the position shift again, and adjusting the position of the warehouse robot until the detected position shift is less than the threshold.

[0018] In some embodiments, the shelves used in the warehouse allow for two or more rows of inventory items to be placed on the shelves. In such warehouses, the warehouse robot and the position information for each inventory item storage are modified or adapted to accommodate the multiple row deep shelves. In a method of controlling a warehouse robot to store or retrieve inventory items for placement on such shelves, the warehouse robot first receives an instruction to transport a first inventory item. The instruction may include a position of the first inventory item, such as, for example, the location, depth, and orientation of the first inventory item. If the depth of the first inventory item indicates that the item is in a front row of the shelf, the robot's retrieval process is the same as the process described above. If the depth of the first inventory item indicates that the item is in a back row of the shelf, the robot's retrieval process may require the robot to remove an inventory item in the front row to reach the first inventory item in the back row. In some configurations, the robot removes the second inventory item from the front row and places it on one empty tray of the robot, then removes the first inventory item from the back row and places it on another empty tray of the robot. The robot then returns to the front row to retrieve the items from the front row. In fact, if the robot is instructed to retrieve the first inventory item and the second inventory item at the same time, and they are just in the same position on different rows, the robot does not need to return to the shelf to retrieve the second inventory item. [Brief description of the drawings]

[0019] These and other features of the present disclosure will become apparent upon further review of the following specification and drawings, in which like reference characters designate corresponding parts in all drawings, and in which the components in the drawings are not necessarily drawn to scale, emphasis instead being placed upon clearly illustrating the principles of the present disclosure. [Figure 1] FIG. 1 is a schematic diagram of an exemplary AGV design for a warehouse. [Diagram 2] FIG. 2 is an exploded view of an exemplary AGV robot. [Diagram 3] FIG. 2 is an exemplary schematic diagram of a lifting device as part of a multi-layer framework. [Figure 4] FIG. 2 is an exemplary schematic diagram of a drive unit. [Diagram 5] FIG. 2 is an exemplary schematic diagram of a motor for use in the drive unit. [Figure 6a] 1 is a schematic diagram of parts of an exemplary material handling device. [Figure 6b] 1 is a schematic diagram of parts of an exemplary material handling device. [Figure 6c] 1 is a schematic diagram of parts of an exemplary material handling device. [Figure 6d] 1 is a schematic diagram of parts of an exemplary material handling device. [Figure 7] 1 is a schematic diagram of a first embodiment of a lateral direction device of an exemplary material conveying device. [Figure 8] 2 is a schematic diagram of a second embodiment of a lateral direction device of an exemplary material conveying device. [Figure 9] 1 is a flowchart of a process in which a warehouse AGV processes an order for picking inventory items. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0020] Hereinafter, the embodiments of the present disclosure will be described more fully with reference to the drawings in which preferred embodiments of the present disclosure are shown. However, various embodiments of the present disclosure may be embodied in many different forms and should not be construed as being limited to the embodiments set forth herein. On the contrary, these embodiments are provided so that the disclosure will be thorough and complete, and the scope of the disclosure will be fully conveyed to those skilled in the art.

[0021] 1, an exemplary AGV 100 includes a driving unit 110, a multi-layered framework 120, and a material conveying device 130. The driving unit 110 is configured to drive and propel the AGV 100. The multi-layered framework 120 includes one or more storage plates 122 and a lifting device 124. The lifting device 124 can be connected to the material conveying device 130 to lift or lower the material conveying device 130. The tray, lateral device, and extendable device included in the material conveying device 130 are described in the latter part of this disclosure, as shown in FIGS. 6a-6d.

[0022] FIG 2 is an exploded view of an exemplary AGV 100. FIG 2 shows the internal components inside the cover 202. In FIG 2, the multi-layer framework 120 is shown to include an upright framework 226, a shelf 228 that houses the storage plate 122, and a lifting device 124. FIG 3 shows further details of the upright framework 226 and the lifting device 124. The upright framework 226 includes two support columns 315 and a number of support rods 316. The lifting device 124 includes two synchronous pulley drives 343 and one lifting drive mechanism 342.

[0023] Two synchronous pulley drives 343 are attached to the support column 315. In some embodiments, the lifting device 124 may include more than one synchronous pulley drive 343. As shown in FIG. 3, each synchronous pulley drive 343 includes a tension pulley 331, a synchronous drive pulley 330, and a synchronous belt 332. The synchronous pulley drive 343 is connected to a lifting drive mechanism 342. The lifting drive mechanism 342 drives the synchronous drive pulley 330 to move the belt 332, thereby lifting the material conveying device 130 up and down along the multi-layered framework 120. In FIG. 3, the exemplary lifting drive mechanism 342 includes an electric motor 320, a drive shaft 321, and a gear box 322. In some embodiments, the electric motor 320 can be replaced with a hydraulic drive system or a pneumatic motor or any other type of motor. The drive shaft 321 connects the synchronous drive pulley 330 and the electric motor 320 through the gear box 322, and transfers the kinetic energy from the electric motor 320 to the synchronous drive pulley 330 to drive the lifting device 124. In some embodiments, the drive shaft 321 connects to two synchronous drive pulleys (not shown) to ensure the synchronous movement of the two pulleys. In FIG. 3, two counterweights 333 are attached on the top of the multi-layered framework 120. Due to the weight loaded on the counterweights 333, the counterweights can move along the support columns 315 and control and buffer the movement and momentum of the lifting device 124. It should be noted that in FIG. 3, the lifting device 124 is realized as a synchronous pulley drive system. Other mechanisms such as sprockets, rack and gears, worm gears and / or lifting screws may also be used to realize the lifting device 124.

[0024] After moving the material conveying device 130 aside, the drive unit 110 is in an open state as shown in Fig. 2. Details of the drive unit 110 are shown in the exploded view of the drive unit 110 in Fig. 4. The drive unit 110 in Fig. 4 includes a base 422, a shaft seat 415 and a shock absorber bracket 425. The support column 315 is fixed to the base 422 so that the multi-layer framework 120 can be attached to the drive unit 110.

[0025] The base 422 has two surfaces, namely, an upper surface 421 and a lower surface 420. On the upper surface 421 of the base 422, an axle seat 415 and a shock absorber bracket 425 are provided for receiving two driving wheels 413 via a driving wheel socket 423 and a mounting socket 424. The mounting socket 424 is in the center of the base 422, and the two driving wheels 413 are below the mounting socket 424 to support the base 422. Four driven wheels 412 are also mounted on the four corners of the base 422 to provide support and facilitate movement. The four driven wheels 412 are mounted in driven wheel sockets 426. In some embodiments, there may be more or less than four driven wheels. The driven wheels may be swivel wheels or other types of steering wheels.

[0026] FIG. 5 shows one embodiment of the driving wheel 413. The driving wheel 413 includes a driving wheel bracket 530, a driving wheel body 531, a hub drive 532, and a hub reduction gear 533. The driving wheel bracket 530 includes a pair of wheel brackets 534, an axle 535, and a pair of shock absorbers 536. The hub drive 532 is mounted at the center of the driving wheel bracket 530 along the central axis S2. The hub drive 532 connects to the driving wheel body 531 and provides driving force to push the driving wheel 413. The hub drive 532 is located between the wheel brackets 534. Two shock absorbers 536 are located on the sides of each wheel bracket 534, respectively. The shock absorbers 536 connect to the shock absorber bracket 425 through the mounting socket 424 as shown in FIG. 4. The wheel bracket 534 connects to the axle 535, which in turn connects to the axle seat 415 via the mounting socket 424. The shock absorber 536 and the wheel bracket 534 form an angle. Such a structure can absorb shock or centrifugal forces, especially when the AGV 100 rotates. In some embodiments, the hub drive 532 can be an electric motor, a hydraulic drive system, a pneumatic motor, or other type of motor.

[0027] As shown in FIG. 1, an exemplary AGV 100 includes a multi-layer framework 120, as shown in FIGS. 2 and 3, a drive unit 110, as shown in FIG. 4, and a material handling device 130, as shown in FIGS. 6a-6d.

[0028] In Figure 6a, the material handling apparatus 130 is shown to include a tray 633, a boom 632, a support framework 631, two slide elements 610, a camera component 640, a primary lighting device 641, and a secondary lighting device 642. There are two booms 632, one on each side of the tray 633. However, only one boom is shown in Figure 6a. Also, only one of the two slide elements 610 is shown in Figure 6a.

[0029] FIG. 6a shows three axes S5, S6, and S7. The material conveying apparatus 130 can contract or extend along S6 by the movement of the slide element 610. The material conveying apparatus 130 can also move laterally in the lateral direction. In some embodiments, to achieve the lateral movement, the material conveying apparatus 130 can be configured to rotate around S5. In one embodiment, the material conveying apparatus 130 is configured to rotate the tray 633 90° to the left or right. In other embodiments, to achieve the lateral movement, the material conveying apparatus 130 can be configured to translate the tray 633 to the left or right. To translate the tray 633, the material conveying apparatus 130 moves the tray 633 in parallel along S7.

[0030] The boom 632 is configured to retract or extend along the slide element 610 and move the tray 633 along the S6 axis. The boom 632 includes a telescopic boom 636 and a push rod component 637 to complete the retraction and extension motion. FIG. 6b is an exploded view of an exemplary material conveying apparatus 130. The exploded view of FIG. 6b illustrates five parts of the material conveying apparatus 130 to show the detailed parts of each part. In FIG. 6a, the tray 633 is illustrated to be located on top of the slide element 610. As shown in FIG. 6b, the tray 633 has been moved aside to expose the structure of the slide element 610.

[0031] In FIG. 6b, the sliding element 610 is connected to a rotating component 638 and a lifting fork 639. The rotating component 638 is configured to rotate the tray 633 about an axis S6. Details of the rotating component 638 are described below, as shown in FIG. 7. In some embodiments, the material conveying apparatus 130 does not rotate the tray 633, but translates the tray 633, as shown in FIG. 8. The sliding element 610 is part of a retraction apparatus, as mentioned elsewhere in this disclosure. The rotating component 638 is part of a lateral apparatus, as mentioned elsewhere in this disclosure. Another embodiment of a lateral apparatus is shown in FIG. 8.

[0032] In FIG. 6b, the push bar component 637 is shown to include a fixed push bar 670, a moving push bar 671, a drive 672, and an inner boom 662. The inner boom 662 can be assembled to the middle boom 661, which can alternatively be assembled to the outer boom 660. The drive 672 can drive the moving push bar 671 to open or close relative to the inner boom 662. The moving push bar 671 can be used to move inventory items to or remove inventory items from the tray 633. A shroud 635 as shown in FIG. 6b can be attached around the periphery of the tray 633 to prevent the contents of the tray 633 from falling off.

[0033] FIG. 6c provides another close-up view of the material handling apparatus 130. Two outer booms 660 are mounted on either side of the tray 633. A camera component 640 and a primary lighting device 641 are mounted to the front of the material handling apparatus 130. FIG. 6c further illustrates a first drive 663 connected to the outer boom 660. FIG. 6d illustrates a second drive 664 connected to the intermediate boom 661. Either the first drive 663 or the second drive 664 includes a telescopic drive (3631, 3641, respectively) and a sprocket chain device (3630, 3640, respectively). In some embodiments, the first drive 663 may include a sprocket chain device and the second drive 664 may include a flat belt device (not shown). In some embodiments, instead of a sprocket chain device or flat belt device, the first drive device 663 or the second drive device 664 may include an open loop flat belt device (not shown) to facilitate extension or retraction movement of the material conveying device 130.

[0034] As described above, the material transport apparatus 130 may be configured to rotate the tray 633 or translate the tray 633 to achieve lateral movement in the process of storing or retrieving inventory items. In a crowded warehouse where storage shelves are arranged in rows, the material transport apparatus 130 that can move laterally to reach the inside of the storage shelves is very advantageous. When the AGV 100 moves between two storage shelves, the material transport apparatus 130 can rotate the tray 633 or translate the tray 633 to the right or left side without having to rotate the entire AGV 100. Since no space is required for the AGV 100 to turn, the space between the shelves can be as narrow as the width of the AGV 100. In this way, the space required when the AGV 100 moves between shelves to pick up or store inventory items is narrower than that of a normal warehouse robot. Figures 7 and 8 show two exemplary embodiments of the lateral movement of the material transport apparatus 130.

[0035] FIG. 7 illustrates a rotation component 638 as shown in FIG. 6b. In FIG. 7, the rotation component 638 includes a rotation drive 712 and a position device 714. The rotation drive 712 includes a drive motor (not shown) and a set of drive gears 724. Illustrative examples of the drive motor include an electric motor, a hydraulic drive system, or a pneumatic motor. Illustrative examples of the drive gears can include a worm shaft, a planetary gear, or other types of gears. The position device 714 includes a first angle sensor 716, a second angle sensor 720, a first proximity switch 726, a second proximity switch 728, and a detection plate 718. The position device 714 further includes a rotation controller, not shown in FIG. 7.

[0036] The first angle sensor 716 and the second angle sensor 720 are located on the circumference of the drive gear 724 and are spaced apart by a certain distance. The two sensors are for detecting whether the tray 633 of the material conveying device 130 has rotated to a previously specified position. When the tray 633 is driven by the drive device 712, the first proximity switch 726 and the second proximity switch 728 move together with the tray 633. By determining when the first or second angle sensor 716, 720 detects which of the first or second proximity switch 726, 728, the amount of angular rotation of the tray 633 can be detected and controlled by the rotation controller.

[0037] 7 controls the boom 632 and tray 633 to rotate 90 degrees to the right or left, thereby providing lateral movement to the material transport apparatus 130 to reach a shelf laterally to the right or left. FIG. 8 shows a different mechanism for the rotation component 638 that may also be used to provide lateral movement of the tray 633.

[0038] In FIG. 8, the boom 632 includes two slide mechanisms, 852 for x-axis movement and 854 for y-axis movement. The slide mechanism 852 moves the boom 632 to allow it to extend or retract. The slide mechanism 854 moves the boom 632 laterally to the left or right. In FIG. 8, two camera components 856 are mounted on either side of the boom 632 for optical detection. Compared to the material conveying apparatus 130 shown in FIG. 6a, which can be configured to rotate 90 degrees to the left or right, the material conveying apparatus 130 driven by the system shown in FIG. 8 can only slide to the left or right instead of rotating. Thus, in FIG. 6a, only one camera component 640 is needed at the front of the material conveying apparatus 130, whereas in FIG. 8, two camera components 856 are mounted on either side of the boom 632.

[0039] 1-8 show an advanced AGV 100 that is flexible and agile. FIG. 9 shows a flow chart of the process of the AGV 100 putting away or retrieving an inventory item. For the purpose of explanation, FIG. 9 shows only the process of retrieving an item. The process of putting away an inventory item is similar to the retrieving process and will not be described in detail for brevity. Those skilled in the art can derive the process of putting away an inventory item from the process of retrieving an inventory item shown in FIG. 9.

[0040] Referring to FIG. 9, the AGV 100 receives a command to pick an inventory item from a warehouse shelf. In some embodiments, the command can simply include an identification code of the inventory item, and the AGV 100 uses the identification code to search for the item's position information. In some embodiments, the command can include the inventory item's position, and the AGV 100 can retrieve the inventory item's position information based on the command. In one embodiment, the position information includes the inventory item's location, such as x and y coordinates or row and column numbers, and the inventory item's orientation and height, such as which layer of the shelf the inventory item is stored in. Based on the item's position information, the AGV 100 navigates around the warehouse to reach the inventory item's location.

[0041] When the AGV 100 reaches the location (step 902), it opens the primary lighting device 641 (step 904). The AGV 100 attempts to read an identification code on the inventory item (step 906). In some embodiments, the identification code may be a two-dimensional bar code. In other embodiments, the identification code may be any bar code. If the AGV 100 is unable to read the identification code, it sends a report to the server and aborts the task (step 950). If the AGV 100 is able to identify the identification code, it calculates the position shift of the inventory item (step 908).

[0042] The AGV 100 is configured to report the acquired inventory item position shift to the server (step 910). The server is configured to use the position shift and the warehouse layout to determine the inventory item's correct location (step 912). The server then updates its database based on the inventory item's correct location (step 914).

[0043] Based on the position shift, the AGV 100 further determines whether the material handling device 130 can reach the inventory item directly from the AGV 100's location (step 924). If so, the AGV 100 further adjusts or fine-tunes the position of the material handling device 130 (step 932), and moves the AGV 100 to slightly adjust the inventory item's position or orientation (step 936) while extending the material handling device 130 (step 934). If so, the AGV 100 further detects whether the tray 633 is within the predetermined range (step 922). If not, the AGV 100 slightly adjusts the AGV's location (step 920) and tries to read the identification code again (step 906). If the tray 633 is within the predetermined range, the AGV 100 adjusts the position of the material handling device 130 to rotate the tray 633 (step 926). Before re-reading the identification code, it is determined whether the position shift is within a threshold (step 928). If the shift is within the threshold, the AGV 100 extends the material handling device 130 and acquires the inventory item (step 930). If the position shift is not reasonable or is not within the predetermined threshold, the AGV 100 extends the material handling device (step 934) and adjusts the position of the AGV 100 and the position of the inventory item (step 936).

[0044] In some embodiments, the AGV 100 is configured to search for and retrieve an inventory item hidden behind an object or another inventory item. The AGV 100 may be configured to receive an instruction from a server for a position of a first inventory item to be retrieved. The position includes a location, a depth, and an orientation of the first inventory item. The AGV 100 is configured to retrieve the first inventory item from a back row of the shelf if there is no inventory item in the previous row. If there is a second inventory item in the previous row, the AGV 100 is configured to retrieve the second inventory item and place the second inventory item in an empty first tray of the multi-layered framework 120. The AGV 100 then retrieves the first inventory item and places the first inventory item in an empty second tray of the multi-layered framework 120. After retrieving the first inventory item, the AGV 100 returns to the shelf housing the second inventory item.

[0045] In some embodiments, shelves used in warehouses may have two or more rows of inventory items placed or stored within them. In such warehouses, the position information for the AGV 100 and the storage of each inventory item may be modified or adjusted to accommodate the multiple rows of deep shelves. In a method of controlling the AGV 100 to store or retrieve inventory items for such shelves, the AGV 100 first receives a command to transport a first inventory item. The command may include the position of the first inventory item, e.g., the location, depth, and orientation of the first inventory item. If the depth of the first inventory item indicates that the item is in a front row of the shelf, the retrieval process by the AGV 100 is the same as the process described above. If the depth of the first inventory item indicates that the item is in a back row of the shelf, the retrieval process by the AGV 100 may require the AGV 100 to remove an inventory item from the front row to reach the first inventory item in the back row. In some configurations, the AGV 100 is configured to pick up a second inventory item located in a front row and place it in one empty tray of the AGV 100, and then pick up the first inventory item from a back row and place it in another empty tray of the AGV 100. The robot then returns the front row of items to the front row. In fact, if the AGV 100 is commanded to pick up the first inventory item and the second inventory item at the same time and they are just in the same position in different rows, the AGV 100 does not need to return to the shelf to pick up the second inventory item.

[0046] In some embodiments, the AGV 100 detects a position shift of the first or second inventory item and adjusts the attitude and position of the AGV 100 and reaches into the shelf to pick up the inventory item. The AGV 100 may be configured to adjust the position of the inventory item before acquiring (the first or second inventory item). In one embodiment, the AGV 100 may repeat the position adjustment process until the detected position shift is less than a threshold. In one embodiment, the AGV 100 may be configured to report the position shift to a server so that the server can update a map of the warehouse. The map of the warehouse may be used to describe the layout, i.e., where the shelves are and where the inventory items are stored.

[0047] Although the present disclosure has been illustrated and described with reference to specific implementations, the disclosure is not intended to be limited to the details shown. Rather, various modifications may be made in the details, within the scope and range of equivalence of the claims, without departing from the disclosure.

Claims

1. 1. An automated guided vehicle designed for storing or retrieving inventory items, comprising: a drive unit configured to drive the automated guided vehicle; a multi-layer frame attached to the drive unit, the multi-layer frame including a lifting device and one or more plates for receiving one or more inventory items; 1. A material conveying apparatus comprising: a tray configured to receive inventory items; a lateral direction device configured to move the tray laterally to the right or left side of the automated guided vehicle; and A stretchable device configured to stretch or contract; A material conveying device comprising: A shift detection device; Equipped with The lifting device is configured to lift and lower the material conveying device; the automated guided vehicle is configured to move between two warehouse shelves and to place one or more of the inventory items on any of the warehouse shelves or to retrieve one or more of the inventory items from any of the warehouse shelves using the material transport device; the shift detection device is configured to detect a shift in the position of the inventory item compared to a position of the inventory item obtained from commands received by the automated guided vehicle; the drive unit is further configured to drive the automated guided vehicle based on the position shift and adjust a position of the automated guided vehicle to compensate for the position shift. Automated guided vehicle.

2. the position obtained from the command received by the automated guided vehicle includes at least one of a location, a depth, a height, and an orientation of the inventory item; 2. The automated guided vehicle according to claim 1.

3. 1. A method for controlling a warehouse robot to store or retrieve inventory items on a shelf, comprising: receiving an order to transport the inventory items; obtaining a position of the inventory item from the received command, the position of the inventory item including a location of the inventory item and an orientation of the inventory item; directing the warehouse robot to move to the location of the inventory item; detecting a position shift of the inventory item away from the captured position based on the location and the orientation of the inventory item; adjusting a position of the warehouse robot to compensate for the position shift; removing the inventory item from the shelf; transporting the inventory to a destination; Including, method.

4. adjusting a position of the warehouse robot to compensate for the position shift, comparing the position shift to a threshold; adjusting a position of the warehouse robot based on the position shift if the position shift is greater than the threshold; measuring the position shift again; adjusting the position of the warehouse robot until the measured position shift is less than the threshold value; Further comprising: The method according to claim 3.

5. and transmitting a position update to a server to report the position shift. The method according to claim 3.

6. The inventory items on the shelf are arranged in two rows, a front row and a rear row, The method comprises: receiving an instruction to transport a first inventory item; obtaining a position of the first inventory item from the received order to transport the first inventory item, the position of the first inventory item including a location, a depth and an orientation of the first inventory item, the depth of the first inventory item indicating that the first inventory item is in the back row; directing the warehouse robot to move to the location of the first inventory item; determining whether a second inventory item is in the previous row in the same position as the first inventory item; extending a material handling device of the warehouse robot to reach the back row of shelves and retrieve the first inventory item if no inventory items are present in front of the first inventory item; if the second inventory item is in front of the first inventory item, removing the second inventory item from the previous row and taking the first inventory item from the subsequent row; Including, The method according to claim 3.

7. An automated guided vehicle, a transceiver configured to receive an instruction to transport an inventory item located on a warehouse shelf, the instruction indicating a position of the inventory item, the position of the inventory item including a location and an orientation of the inventory item; a drive unit configured to drive the automated guided vehicle to move to the location of the inventory item; a shift detection device configured to detect a position shift of the inventory item compared to the position of the inventory item indicated by the command, the shift detection device being further configured to drive the automated guided vehicle based on the position shift to adjust a position of the automated guided vehicle to compensate for the position shift; a material handling device configured to remove the inventory item from the warehouse shelf after the position shift has been compensated for; Equipped with Automated guided vehicle.

8. the shift detection device is configured to detect the position shift before the automated guided vehicle reaches the location of the inventory item.

8. The automated guided vehicle according to claim 7.

Images