Cargo handling devices

Abstract

A cargo handling device designed to operate at the top of a cube-shaped automated storage and retrieval system (ASRS). The cargo handling device has two wireless network interfaces, with one or more antennas connected to each wireless network interface. The cargo handling device can establish two simultaneous wireless communication links to different wireless access points. One of the links is used as the primary link for controlling the cargo handling device, and the other link is used as the secondary link.

Description

[Technical Field]

[0001] This application claims priority from UK Patent Application No. GB2311974.6, filed on 4 August 2023, and UK Patent Application No. GB2311965.4, filed on 4 August 2023, the contents of which are incorporated herein by reference.

[0002] This disclosure relates to a cargo handling device, and more particularly to a robotic cargo handling device that can operate on a grid within a warehouse facility while connected to a wireless local area network. [Background technology]

[0003] Grid-based automated storage and retrieval systems are well known in the art. In such systems, multiple robotic load handlers operate on a horizontal grid structure, below which multiple containers arranged in multiple stacks are received. The containers are used to hold products, and the load handlers are adapted to retrieve containers from one of the multiple stacks and place them in one of the stacks. The load handlers may be routed autonomously (or semi-autonomously) on the grid, but a wireless communication system is required to send commands to the load handlers and to enable each load handler to communicate with a management system. The apparatus, method, system, and computer program described in the claims are intended to provide improvements to a communication system for use in an automated storage and retrieval system using a fleet of robotic load handlers. [Overview of the project]

[0004] According to a first aspect of the present disclosure, a cargo handling device is provided for use in a storage system, the cargo handling device comprising a first network interface and a second network interface, the cargo handling device being configured to establish a first communication link to the storage system using the first network interface and a second communication link to the storage system using the second network interface when in use. One of the communication links may be a primary communication link, in which data transmitted and received via the first communication link is used to control the operation of the cargo handling device. The other communication link may be a secondary communication link, in which data transmitted and received via the secondary communication link is a copy of the data transmitted and received via the primary communication link.

[0005] The use of two simultaneous network connections allows one connection to be used to transmit data between the cargo handling device and the storage system, while the other connection remains ready for use. The other connection can be switched between wireless access points within the storage system, allowing the cargo handling device to move through the storage system without losing connectivity and reducing the risk of data loss.

[0006] A first communication link may exist between a first network interface and a first access point of a first access point group, and a second communication link may exist between a second network interface and a second access point of a first access point group. In particular, a first communication link may exist between a first network interface and a first access point of a first access point group, and a second communication link may exist between a second network interface and a first access point of a second access point group.

[0007] The first or second communication link may be designated as a primary communication link according to one or more measured parameters. The primary communication link may be transmitted between the first and second communication links according to one or more measured parameters.

[0008] The decision to designate the first or second communication link as the primary communication link may be made according to the location of the cargo handling device within the storage system. The cargo handling device may have a lookup table containing data on the network status at each storage system location, and this network status data is used in the decision to designate the first or second communication link as the primary communication link. The primary communication link may be transmitted between the first and second communication links according to the location of the cargo handling device within the storage system. The primary communication link may also be transmitted between the first and second communication links according to the direction of movement of the cargo handling device within the storage system.

[0009] The decision to designate the first or second communication link as the primary communication link may be made according to data received by the cargo handling device from the storage system. More specifically, the primary communication link may be transferred between the first and second communication links according to further data received by the cargo handling system from the storage system. The cargo handling device may be configured to change the first and / or second communication links in response to receiving control messages from the storage system. The cargo handling device may be configured to change the first and / or second communication links to different wireless access points within an existing group of access points. Alternatively, the cargo handling device may be configured to change the first and / or second communication links to wireless access points within a different group of access points. If the primary communication link is lost, the secondary communication link is designated as the primary link, but the existing connection to the wireless access point is maintained.

[0010] According to a second aspect of the present disclosure, a storage system is provided comprising: a first set of parallel tracks extending in the X direction and a second set of parallel rails extending in the Y direction traversing the first set, in a substantially horizontal plane, so as to form a grid pattern comprising a plurality of grid spaces; a plurality of stacks of storage containers located beneath the tracks and arranged such that each stack is located within the footprint of a single grid space; and at least one of the above-described loading handling devices, the at least one loading handling device positioned above the stacks on the tracks and positioned to move selectively in the X and Y directions, for transporting the storage containers.

[0011] According to a third aspect of the present disclosure, a communication network is provided for use in a storage system, the communication network comprising one or more wireless access point groups, the or each wireless access point group comprising a plurality of wireless access points.

[0012] The communication network may be configured to establish a first communication link to the cargo handling device via a first wireless access point and a second communication link to the cargo handling device via a second access point when in use. The first communication link may be established via wireless access points in a first wireless access point group. The second communication link may be established via wireless access points in a second wireless access point group. The first communication link may be used to transmit control signals and safety signals to the cargo handling device. The second communication link may be a backup link in case the first communication link is lost.

[0013] A further aspect of the present disclosure provides a method for establishing a communication link between a storage system and one or more cargo handling devices operating within the storage system, wherein the storage system comprises a plurality of wireless access points, and the method comprises: a) determining, for each location in the storage system, one or more parameter values ​​for each of the plurality of wireless access points, primarily at that location; and b) determining, for each location in the storage system, a preferred wireless access point for a cargo handling device to be used for a primary connection at that location, according to the one or more parameter values ​​determined in step a). The method may further comprise c) determining, for each location in the storage system, one or more wireless access points for a cargo handling device to be used for a secondary connection at that location, according to the one or more parameter values ​​determined in step a).

[0014] In step a), one or more parameter values ​​may be measured, and the measurement may be performed by one or more cargo handling devices. Alternatively, one or more parameter values ​​may be calculated based on a theoretical model. One or more of the multiple cargo handling devices operating within the storage system may periodically report the measured parameter values, and the reported measured parameter values ​​are used to update the parameter values ​​determined in step a).

[0015] One or more parameter values can be used to generate a lookup table that holds one or more parameter values for each location within the storage system. The lookup table can be periodically transmitted to one or more of a plurality of load handling devices operating within the storage system. Alternatively, a portion of the lookup table is periodically transmitted to one or more of a plurality of load handling devices operating within the storage system. The lookup table may include identification information of one or more wireless access points suitable for supporting a primary connection for each location within the storage system. The lookup table may further include identification information of one or more wireless access points suitable for supporting a secondary connection for each location within the storage system. Alternatively, the lookup table may include identification information of one or more wireless access points that are not suitable for supporting a primary or secondary connection for each location within the storage system.

Brief Description of the Drawings

[0016] Referring to an example, the load handling device will be described in detail. [Figure 1] FIG. 1 schematically illustrates a storage structure and a container. [Figure 2] FIG. 2 schematically illustrates a track above the storage structure illustrated in FIG. 1. [Figure 3] FIG. 3 schematically illustrates a load handling device above the storage structure illustrated in FIG. 1. [Figure 4] FIG. 4 schematically illustrates a single load handling device in which the container lifting unit is in a lowered configuration. [Figure 5] FIG. 5 schematically illustrates a cutaway view of a single load handling device in which the container lifting unit is in a raised and lowered configuration. [Figure 6] FIG. 6 shows a schematic diagram of a communication system according to the present invention. [Figure 7] FIG. 7 shows a schematic diagram of a bot for use with the communication system of the present disclosure. [Figure 8]FIG. 8 shows a schematic diagram of a grid covered by a first coverage area and a second coverage area. [Figure 9] FIG. 9 shows a schematic diagram of a further configuration in which the grid is covered using four WiFi coverage areas. [Figure 10] FIG. 10 shows a schematic diagram of a computer device that can be used to execute the method according to the present disclosure.

DETAILED DESCRIPTION OF THE INVENTION

[0017] The following embodiments represent the preferred examples of the applicant of how to implement a communication system for use with robots in a warehouse, but they are not necessarily the only examples of how it can be achieved.

[0018] FIG. 1 illustrates a storage structure 1 comprising a vertical member 3 and horizontal members 5, 7 supported by the vertical member 3. The horizontal members 5 extend parallel to each other and to the illustrated x-axis. The horizontal members 7 extend parallel to each other and to the illustrated y-axis and transversely to the horizontal members 5. The vertical members 3 extend parallel to each other and to the illustrated z-axis and transversely to the horizontal members 5, 7. The horizontal members 5, 7 form a grid pattern that defines a plurality of grid cells. In the illustrated example, the container 9 is arranged in a stack 11 under a grid cell defined by the grid pattern, with one stack 11 of the container 9 per grid cell.

[0019] Figure 2 shows an enlarged plan view of a section of a track structure 13 that forms part of the storage structure 1 shown in Figure 1 and is located above the horizontal members 5, 7 of the storage structure 1 shown in Figure 1. The track structure 13 may be provided by the horizontal members 5, 7 themselves (for example, formed within or on the surface of the horizontal members 5, 7) or by one or more additional components attached to the top of the horizontal members 5, 7. The illustrated track structure 13 comprises x-direction tracks 17 and y-direction tracks 19, i.e., a first set of tracks 17 extending in the x direction and a second set of tracks 19 extending in the y direction, traversing the tracks 17 in the first set of tracks 17. The tracks 17, 19 define an opening 15 in the center of the grid cell. The opening 15 is sized to allow containers 9 located below the grid cell to be lifted and lowered through the opening 15. The x-direction tracks 17 are provided in pairs separated by channels 21, and the y-direction tracks 19 are provided in pairs separated by channels 23. Other arrangements of the track structure may also be possible.

[0020] Figure 3 shows a plurality of load handling devices 31 moving over the storage structure 1 illustrated in Figure 1. The load handling devices 31, which may also be called robots 31 or bots 31, are provided with a set of wheels for engaging with corresponding x-direction tracks 17 or y-direction tracks 19, enabling the bots 31 to move across the track structure 13 and reach specific grid cells. The illustrated pairs of tracks 17, 19, separated by channels 21, 23, allow the bots 31 to occupy (or pass through) neighboring grid cells without colliding with each other.

[0021] As illustrated in detail in Figure 4, the bot 31 comprises a body 33 in which one or more components are attached or attached thereto, enabling the bot 31 to perform its intended function. These functions may include moving across the storage structure 1 on the track structure 13 and raising or lowering containers 9 (e.g., from or to stack 11), thereby enabling the bot 31 to retrieve or place containers 9 at specific locations defined by the grid pattern.

[0022] The illustrated bot 31 comprises a first set of wheels 35 and a second set of wheels 37, which are mounted on the body 33 of the bot 31, allowing the bot 31 to move along tracks 17 and 19 in the x and y directions, respectively. In particular, two wheels 35 are provided on the shorter side of the bot 31 as seen in Figure 4, and two additional wheels 35 are provided on the opposite short side of the bot 31 (the side and the additional two wheels 35 are not visible in Figure 4). The wheels 35 engage with the track 17 and are rotatably mounted on the body 33 of the bot 31, allowing the bot 31 to move along the track 17. Similarly, two wheels 37 are provided on the longer side of the bot 31 as seen in Figure 4, and two additional wheels 37 are provided on the opposite long side of the bot 31 (the side and the additional two wheels 37 are not visible in Figure 4). The wheels 37 engage with the track 19 and are rotatably mounted on the body 33 of the bot 31, allowing the bot 31 to move along the track 19.

[0023] Bot 31 also includes a container lifting unit 39 configured to raise and lower the container 9. The illustrated container lifting unit 39 comprises four tapes or reels 41, which are connected at their lower ends to a container engagement assembly 43. The container engagement assembly 43 comprises an engagement mechanism configured to engage with the features of the container 9 (this may be provided, for example, at the corners of the assembly 43 near the tapes 41). For example, these containers 9 may have one or more openings on their upper sides into which the engagement mechanism can engage. Alternatively or additionally, the engagement mechanism may be configured to hook under the rim or lip of the container 9 and / or clamp or grip the container 9. The tapes 41 may be wound up or unwound as needed to raise or lower the container engagement assembly. One or more motors or other means may be provided to wind up or unwind the tapes 41.

[0024] As can be seen in Figure 5, the body 33 of the illustrated bot 31 has an upper part 45 and a lower part 47. The upper part 45 is configured to accommodate one or more operating components (not shown). The lower part 47 is located below the upper part 45. The lower part 47 has a container receiving space or cavity for accommodating at least a portion of the container 9 lifted by the container lifting unit 39. The container receiving space is sized so that the container 9 fits sufficiently inside the cavity, allowing the bot 31 to move across the track structure 13 on top of the storage structure 1 without the lower side of the container 9 getting caught on the track structure 13 or another part of the storage structure 1. When the bot 31 reaches its intended destination, the container lifting unit 39 controls the tape 41 to lower the container gripping assembly 43 and the corresponding container 9 out of the cavity in the lower part 47 to the intended position. The intended location may be the stack 11 of containers 9 or the exit point of the storage structure 1 (or, if the bot 31 has moved to collect containers 9 for storage within the storage structure 1, the entry point of the storage structure 1). In the illustrated example, the upper portion 45 and the lower portion 47 are separated by a physical partition, but the upper portion 45 and the lower portion 47 may not be physically separated by certain components or parts of the body 33 of the bot 31. As will be understood by those skilled in the art, the bots shown in Figures 3 to 5 are cavity bots in which containers are received into a cavity inside the bot, but this disclosure is equally relevant to cantilever bots or other bots or autonomous vehicles in a storage system communicating via a wireless LAN.

[0025] To enable the bot 31 to move in first and second directions over different wheels 35, 37, the bot 31 includes a wheel positioning mechanism for selectively engaging a first set of wheels 35 with a first set of wheels 17, or a second set of wheels 37 with a second set of wheels 19. The wheel positioning mechanism is configured to raise and lower the first set of wheels 35 and / or the second set of wheels 37 relative to the body 33, thereby enabling the load handling device 31 to selectively move across the tracks 17, 19 of the storage structure 1 in either a first or second direction.

[0026] The wheel positioning mechanism may include one or more linear actuators, rotating components, or other means for raising and lowering at least one set of wheels 35, 37 relative to the body 33 of the bot 31, thereby removing at least one set of wheels 35, 37 from the tracks 17, 19 and bringing it into contact with the tracks 17, 19. In some examples, only one set of wheels may be configured to raise and lower, where the action of lowering one set of wheels can effectively lift the other set of wheels away from the corresponding tracks, while the action of raising one set of wheels can effectively lower the other set of wheels into contact with the corresponding tracks. In other examples, both sets of wheels may be raised and lowered, which is advantageous as it means the body 33 of the bot 31 remains at substantially the same height and therefore the weight of the body 33 and any components mounted thereon does not need to be raised and lowered by the wheel positioning mechanism.

[0027] To remove container 9 from the top of stack 11, bot 31 is moved in the X and Y directions as necessary so that the container gripping assembly 43 is positioned above stack 11. The container gripping assembly 43 is then lowered vertically in the Z direction to engage with container 9 at the top of stack 11. The container gripping assembly 43 grips container 9 and is then pulled upward along tape 41 with container 10 attached. At the top of its vertical movement, the container 9 is housed beneath the vehicle body 32 and held on the level of the truck. In this manner, the loading handling device 30 can be moved to different positions in the XY plane to transport the container 9 to a different location, carrying the container 9 together with the loading handling device 30. The tape 41 is long enough so that the loading handling device 30 can take and place the container from any level of the stack 11, including the floor level. The weight of the vehicle may include some batteries used to power the drive mechanisms of the wheels 35, 37.

[0028] As shown in Figure 3, multiple cargo handling devices 31 are provided, and each bot 31 can operate simultaneously to increase the system throughput. The system illustrated in Figure 3 may include specific locations known as ports, where containers 9 can be transferred to or from the system. Additional conveyor systems (not shown) are associated with each port, so that containers 9 transported to a port by a bot 31 can be transported by the conveyor system to another location, for example, a picking station (not shown). Similarly, containers 9 can be moved by the conveyor system from an external location to a port, for example, a container filling station (not shown), and then transported by a bot 31 to a stack 11 to replenish inventory in the system.

[0029] Each bot 31 can lift and move one container 9 at a time. If it is necessary to retrieve a container that is not located on top of the stack 11 ("target container"), the lying containers 10 ("non-target containers") must first be moved to allow access to the target container 10. This is achieved in an operation referred to below as "digging". During the digging operation, one of the bots 31 sequentially lifts each non-target container 9a from the stack 11 containing the target container 9b and places them in an empty position in another stack 11. The target container 9b can then be accessed by bot 31 and moved to a port for further transport.

[0030] Each of the bots 31 is under the control of the grid controller. Each individual container 9 in the system is tracked, and the appropriate container 9 can be retrieved, transported, and replaced as needed. For example, the location of each non-target container is logged so that non-target containers can be tracked during digging operations.

[0031] The system described with reference to Figures 1 to 5 has many advantages and is suitable for a wide range of storage and retrieval operations. In particular, it allows for very dense storage of products and provides a very economical way to store a large range of different items in container 9, while also allowing rational and economical access to all of container 9 when needed for picking.

[0032] It should be understood that messages need to be sent to the bot. These may be short messages, such as an instruction to move a container from a first location to a second location, or longer messages, such as updates to the computer code used to operate the bot or its components. Similarly, the bot may need to send messages to a central management system to report, for example, operational parameter values, operational status reports, etc. Examples of usable communication systems are disclosed in the applicant's international patent application WO2015 / 185726.

[0033] Figure 6 shows a schematic diagram of the communication system 100 according to the present disclosure, and the fulfillment center comprises a grid 50 on which multiple bots 31 (not shown) move and operate, as described above with reference to Figures 1 to 5. The communication system 100 comprises two wireless access point groups 300A and 300B, each having associated coverage areas 310A and 310B (indicated by dashed lines). It should be understood that the shapes of the coverage areas are merely illustrative and are not intended to represent the coverage areas achieved within the communication system according to the present disclosure.

[0034] It is found that wireless access point groups 300A and 300B are positioned relative to grid 50 such that the entire grid is covered by at least one of the access point groups. Furthermore, it is found that the first coverage area 310A overlaps with the second coverage area 310B to a portion of the grid. A bot operating within the first coverage area 310A can communicate with the first wireless access point group 300A. A bot operating within the second coverage area 310B can communicate with the second wireless access point group 300B. A bot operating within the overlapping area of ​​the grid can communicate with either or both of the wireless access point groups 310A and 310B.

[0035] Each of the wireless access point groups 300A and 300B is connected to a gateway 350, which is communicatively connected to a central computing system 400. The central computing system controls and coordinates the operation of the bot and other entities active within the storage system. Each access point group comprises multiple access points. In the example shown in Figure 6, each of the first and second access point groups comprises two access points. In particular, the first access point group 300A comprises the first access point 302 11 and the second access point 302 12 The second access point group is equipped with the third access point 302 21 and the 4th access point 302 22 It includes the following. Please understand that each access point group can have more access points. Figure 6 shows that each access point in an access point group is located in the same place, but please understand that this is not required, and they may be located separately.

[0036] Notwithstanding the above description relating to Figures 4 and 5, Figure 7 shows a schematic diagram of a bot 31 for use with the communication system of the present disclosure. The bot 31 further comprises a first wireless antenna 32a, a second wireless antenna 32b, a first wireless network card 42a, a second wireless network card 42b, a security receiver 36, a real-time controller 38, and a bot PC 40. The first and second wireless antennas 32a and 32b are located outside the bot body 33 and are configured to receive signals transmitted by the access point. The first wireless antenna 32a is connected to the first wireless network card 42a so that data received via the first wireless network card 42a is routed to the security receiver 36 and the bot PC 40. Similarly, the second wireless antenna 32b is connected to the second wireless network card 42b so that data received via the second wireless network card 42b is routed to the security receiver 36 and the bot PC 40. In an alternative configuration, the first and second wireless network cards 42a and 42b may each be connected to their respective antenna groups. For example, the first and second wireless network cards 42a and 42b may each be connected to their respective antenna groups, each containing two antennas, thereby allowing each antenna in the antenna group to form a spatial stream.

[0037] The signal received by the bot comprises both a control signal and a safety signal. In one example, the control signal may be generated and transmitted separately from the safety signal. In an alternative example, the control signal and safety signal may be transmitted together as a composite signal. In such a case, additional components may be provided to separate the control signal and the safety signal (not shown in Figure 7).

[0038] The received control signals are processed by the bot PC 40. The bot PC 40 communicates with the first set of wheels 35 and the second set of wheels 37, and can send signals to activate the first set of wheels or the second set of wheels as appropriate. The bot PC 40 also communicates with the container lifting unit 39 (see Figures 4 and 5) and can control the container lifting unit for purposes such as lifting a container from a stack in the grid structure into the bot, or lowering a container from inside the bot into a stack in the grid. Thus, the bot PC can interpret and execute control signals so that the bot can operate efficiently as part of a group of bots operating on the surface of the grid.

[0039] The received safety signal is processed by the safety receiver 36. If safety conditions are detected by the safety receiver, the safety receiver may cause the real-time controller 38 to send a safety control signal to the bot PC 40. Receipt of the safety control signal from the real-time controller invalidates the control signal received by the bot PC from the grid controller so that the bot's operation stops. If the bot is in the process of moving from a first grid position to a second grid position, the bot stops at its current position. A stationary bot in the process of lifting or lowering a container can complete its action, but will not take any further action until the safety control signal is invalidated.

[0040] During operation, the bot may use one of the wireless network cards to establish a first connection with one of the access points in the access point group via one or more antennas associated with that network card. The bot may also use other wireless network cards (and one or more antennas associated with that wireless network card) to establish a second connection with further access points in the access point group. One of the connections, for example, the first connection, may be considered a primary connection, used to receive control and safety signals from the central computing system (and to send data back to the central computing system). In such an example, the second connection may be designated as a backup connection, used to receive a second copy of the control and safety signals from the central computing system.

[0041] If the first connection is lost or interrupted, control signals and safety signals received via the second connection can be processed by the bot PC and safety receiver to operate the bot, and any data that needs to be sent to the central computing system can be transmitted using the second connection. Thus, the use of two parallel connections is seen to reduce the risk of the link between the bot and the central computing system being lost. In an alternative configuration, the secondary connection may be a channel used only when the primary connection is lost, and control signals and safety signals can be transmitted via the secondary connection.

[0042] Figure 8 shows a schematic diagram of grid 50, which is a simplified diagram of the grid described above with respect to Figure 6. The grid is covered by a first coverage area 310A and a second coverage area 310B, which are associated with a first access point group 300A and a second access point group 300B (neither of which are shown in Figure 8 for clarity). Consider a scenario in which a bot is instructed to move from location A to location B in order to retrieve a container stored at location B. The bot must then move to location C so that the container can be placed at location C. At location A, the bot is within the second coverage area 310B and therefore can only connect to the second access point group 300B. For example, the bot's first wireless network card 42a and third wireless access point 302 21 A first connection can be made between the second wireless network card 42b and the fourth wireless access point 302. 22 A second connection can be made between them.

[0043] As the bot moves from location A to location B, the bot moves from a location where it can connect only to access points in the second access point group to a location where it can connect to access points from either the first or second access point group (i.e., the bot is moving into overlapping territory). Upon reaching such a point, the bot may request to release one of the first or second connections and make a further connection to one of the access points in the first access point group. For example, the bot may decide to release the connection with the lowest performance metric value. This may be, for example, the connection with the lowest RSSI (Received Signal Strength Indicator) value. It should be understood that other parameters or measurements of signal strength and / or quality may be used. The wireless network card associated with the released connection is the first wireless access point 302 11or to the second wireless access point 302 12 Connect to either one. The connection to either the first wireless access point or the second wireless access point can be made according to the value of the performance metric. For example, the connection can be made to the wireless access point that can provide the highest RSSI value for the relevant connection. For example, the bot can maintain a first connection between the first wireless network card 42a and the third wireless access point 302 21 and may establish a second connection between the second wireless network card 42b and the second wireless access point 302 12

[0044] After the container is removed at position B, the bot moves to position C. When the bot exits the overlapping area, it can no longer connect to the access points within the second access point group 300B. As a result of this movement, the first connection between the first wireless network card 42a and the third wireless access point 302 21 can no longer be maintained and is dropped. In this case, the bot forms a further connection between the first wireless network card 42a and the first wireless access point 302 11 There is

[0045] From the above example, it can be seen that the bot maintains two connections when moving across the grid. At position A, the bot has a first connection to the third wireless access point 302 21 and a second connection to the fourth wireless access point 302 22 The bot assigns one of these connections as the primary connection and the other connection as the secondary connection. When the bot moves into the overlapping area when approaching position B, the secondary connection to the wireless access points within the second access point group 300B is dropped and reconnected to the wireless access points within the first access point group 300A.

[0046] ​ As the bot moves toward position C, and as the bot moves further away from the second access point group 300B and approaches the first access point group 300A, the strength of the secondary connection increases relative to the strength of the primary connection. When the ratio of signal strengths reaches a predetermined level, the secondary connection becomes the primary connection, and the previous primary connection becomes the secondary connection. For example, this can occur when the signal strength of the secondary connection becomes equal to the signal strength of the primary connection, but it should be understood that different thresholds or conditions may be used.

[0047] As the bot moves further toward position C, it leaves the overlapping area, and therefore the secondary connection to the wireless access point in the second access point group 300B is dropped, and it reconnects to the wireless access point in the first access point group 300A, resulting in both primary and secondary connections being between the bot and the first access point group 300A. During the bot's movement, the primary connection is used to send and receive data used to control the bot's movement and operation, and the secondary connection is maintained in case the primary connection is lost. It should be understood that when the bot is moving through an area where both connections are to the same first access point group, the bot may reconfigure itself so that the first connection becomes secondary from being primary, and therefore the second connection becomes primary from being secondary.

[0048] Figure 9 shows a schematic diagram of a further configuration in which grid 50' is covered using four WiFi coverage areas 310A, 310B, 310C, and 310D. Since grid 50' in Figure 9 covers a larger area than grid 50 in Figure 8, such an arrangement may be required because more bots will be operating on grid 50' in Figure 9, or for some other reason. Bots moving from a first coverage area to a second coverage area, moving to or passing through one or more overlapping areas, manage the first and second network connections using the same principles described above with reference to Figure 8. It should be understood that the number of WiFi access point groups (and therefore the number of coverage areas) required to cover the grid of the automated storage and retrieval system will vary depending on the size and shape of the grid.

[0049] In one example of this disclosure, the signal strength and / or quality in each grid cell may be calculated using a theoretical model, depending on the size and shape of the storage system grid, the number of installed access point groups and their positions relative to the grid, the number of access points within each access point group (which may vary between access point groups), and the position and size of structural elements within the grid (e.g., columns supporting the roof). Based on these calculations, it is possible to generate a list of access points accessible from each grid location, thereby allowing the access points to be used by the cargo handling device for either primary or secondary connections.

[0050] In an alternative example of this disclosure, once the storage system is constructed, a small number of bots may be guided onto the storage system's grid and then controlled to move around the grid, thereby measuring signal strength and / or quality for each grid location. The measured data is then reported to and collated in a central computing system. The collated data can then be used to generate a list of access points accessible from each grid location, thereby allowing the access points to be used by cargo handling devices for either primary or secondary connections.

[0051] In a further example, a list of access points may be calculated based on a theoretical model, and then a small number of bots may be used to measure signal strength and / or quality at each grid location, with the measured data being compared to the theoretical calculations. The list of access points may be updated according to the measured data. The measured data may also be used to modify and update the theoretical model used to calculate signal strength and / or quality.

[0052] The access point list can be used to generate a mapping table that can be sent to each bot that can be used with the storage system. The mapping table can take the form of one or more preferred access points for primary connections and one or more preferred access points for secondary connections for each grid location in the storage system.

[0053] In an alternative configuration, each access point accessible from a grid location can be classified. For example, each accessible access point may be classified as red, yellow, or green. Access points classified as red are accessible from a grid location, but their signal strength and / or quality does not provide a reliable connection. Access points classified as yellow have signal strength and / or quality that is suitable for use as a secondary connection, but is not considered to be of sufficient quality to support a primary connection. Access points classified as green have signal strength and / or quality that is of sufficient quality to support a primary connection. Therefore, a bot may use a green access point for its primary connection and a yellow access point for its secondary connection. If sufficient network capacity is available, a bot may be able to use a green access point for its secondary connection.

[0054] If the creation of a mapping table indicates that a grid area has relatively insufficient coverage, for example, a low ratio of green access points to yellow access points, this information can be used when reconfiguring the network. For example, one or more additional access points may be added to the access point group, or beamforming may be used if the wireless access points include MIMO (multiple input multiple output) antennas. It should be understood that the mapping table can take a different form than those described above.

[0055] Once a mapping table is generated, it can be sent by the central computing system to each of the active bots in the storage system. When a bot is guided onto the grid, the mapping table is checked to ensure it is up-to-date, and if not, the central computing system can push an update. It will be understood that when the storage system is operational, the presence of many bots on the grid (large storage systems may have hundreds of active bots) can affect signal strength due to reflection or other interference. Some or all of the active bots may periodically report their measured signal strength to the central computing system, and the reported data may be used to update the mapping table. The updated areas of the mapping table can then be sent to the active bots.

[0056] From Figure 8 and the above description of the bot's movement from location A to location C, it is clear that the bot needs to connect to an access point within the first group of access points. It is desirable to minimize the number of reconnections that occur while the bot moves from A to C. Once the bot's route is determined (e.g., supplied to the bot from a central computing system or determined by the bot PC), the route data can be compared with a mapping table. If possible, when the bot moves to an overlapping area, secondary connections are made to access points that can support secondary connections in the overlapping area (i.e., access points classified as green or yellow in the above example), and to access points that can also support primary connections near and at location C (i.e., access points classified as green in the above example). If this is not possible, the access points may be selected to minimize the number of reconnections required while the bot moves along a predetermined route. Furthermore, the data held by the mapping table may be used to initiate a handover from the first access point to the second access point, thereby ensuring that secondary connections are maintained at a desirable quality level, for example, by initiating a handover to avoid connections to red access points for part of the route.

[0057] The operation of the storage system can lead to situations where an unbalanced number of bots are clustered in a relatively small area of ​​the grid. In such cases, too many bots may attempt to connect to access points suitable for supporting primary connections (i.e., access points classified as green in the example above). An excessive number of connection attempts can degrade network performance. In such cases, the central computing system can initiate load balancing procedures to ensure that primary connections are more evenly distributed across access points suitable for supporting primary connections. Furthermore, one or more bots may cause their primary connections to be remade to access points suitable for use as secondary connections under normal conditions (i.e., access points classified as yellow in the example above). In some cases, it may also be necessary to recreate one or more secondary connections to lower-quality access points (i.e., access points classified as red in the example above) so that there is capacity to reallocate one or more primary connections.

[0058] As an alternative to, or in addition to, this load balancing procedure, the network may be reconfigured to provide temporary additional capacity, for example, by reconfiguring MIMO antennas to provide more bandwidth to areas where bots are concentrated, or by activating inactive access points within an access point group. After the bots have been distributed, the load balancing and / or network reconfiguration may be reversed.

[0059] Please understand that frequent calls for load balancing and / or network reconfiguration may be used as an instruction that permanent changes to the network configuration may be required, such as installing one or more new access point groups, relocating one or more existing access point groups, or adding one or more new access points to existing access point groups.

[0060] There are several situations in which the connection between the bot and one of the access points may be lost. For example, the access point supporting the connection may fail, or there may be a failure in the bot related to, for example, one of the wireless antennas 32 or one of the wireless network interfaces 42. If the bot fails, it needs to be recovered for maintenance activities. The bot can be remotely controlled to move to and from a maintenance area using one operational connection. When the bot moves to an overlapping area, the bot needs to terminate the operational connection and then make a new connection to the access point in the area where the bot will move. This process needs to be repeated when the bot navigates across the grid.

[0061] If an access point fails, the bot attempts to establish a connection using the antenna and network interface previously connected to the access point. Referring to the example described above with respect to Figure 8, the bot is near location A and the fourth wireless access point 302 22 If the connection to the first wireless access point 302 is lost, the bot will attempt to establish a secondary connection to the first wireless access point 302. 11 or second wireless access point 302 12 It attempts to connect to one of the following. If such a secondary connection is possible, the bot may continue moving to location C to complete its action. If an access point fails, the bot's behavior may be modified so that a lower quality connection can be used for the primary and / or secondary connection. Using the example above, a potential connection classified as yellow may be used for the primary connection. Similarly, a potential connection classified as red may be used for the secondary connection.

[0062] When an access point fails, the group of access points associated with that access point will experience a reduction in network capacity. In such a situation, the central computing system can modify the routing algorithm used to determine the route of bots from one location to another so that fewer bots are routed through the area covered by the affected group of access points. Where possible, some of the capacity loss can be mitigated, for example, by activating an additional access point or by activating beamforming on other access points. Once the access point is restored, the storage system can return to normal operation.

[0063] Referring again to the example above, the bot is at the first wireless access point 302 11 or second wireless access point 302 21 If it is unable to connect to any of the access points, the bot will be left with only a single operational connection. This is equivalent to a situation where the bot's antenna or network interface has failed. In such a case, the bot can be remotely controlled using the operational connection until it can be routed to a location where a secondary connection to a further access point can be established. Once the secondary connection is established, the bot can continue normal operation.

[0064] Access points and wireless network interfaces may be selected to comply with one of the wireless LAN standards, such as IEEE 8021.11n (sometimes called WiFi 4), 802.11ac (WiFi 5), or 802.11ax (WiFi 6). Further standards may be agreed upon and compliant devices released (e.g., 8021.11 [WiFi 7]). It will be understood that standards-compliant devices are selected to provide the desired level of network capacity and performance. From the above explanation, it will be understood that the native capabilities of access points and wireless network interfaces are used to manage channels and other aspects within the wireless LAN.

[0065] The system and method may be implemented in various embodiments. Appropriately configured computer devices, and associated communication networks, devices, software, and firmware may provide a platform for enabling one or more embodiments as described above. As an example, Figure 10 shows a schematic diagram of a computer device 1000 which may include a central processing unit ("CPU") 1002 connected to a storage unit 1014 and random access memory 1006. The CPU 1002 may process an operating system 1001, an application program 1003, and data 1023. The operating system 1001, the application program 1003, and the data 1023 may be stored in the storage unit 1014 and loaded into memory 1006 as needed. The computer device 1000 may further include a graphics processing unit (GPU) 1022 operably connected to the CPU 1002 and memory 1006 to offload intensive image processing calculations from the CPU 1002 and perform these calculations in parallel with the CPU 1002. Operator 1007 may interact with computer device 1000 using a video display 1008 connected by video interface 1005, and various input / output devices such as a keyboard 1015, mouse 1012, and disk drive or solid-state drive 1014 connected by I / O interface 1004. In known ways, the mouse 1012 may be configured to control the movement of a cursor in the video display 1008 and to operate various graphical user interface (GUI) controls that appear in the video display 1008 with mouse buttons. The disk drive or solid-state drive 1014 may be configured to accept computer-readable media 1016. Computer device 1000 may form part of a network via network interface 1011 to enable computer device 1000 to communicate with other appropriately configured data processing systems (not shown).One or more different types of sensors 1035 may be used to receive input from various sources.

[0066] The system and method may be implemented in substantially any way on a computer device, including a desktop computer, laptop computer, tablet computer, or wireless handheld. The system and method may also be implemented as a computer-readable / usable medium containing computer program code to enable one or more computer devices to perform each of the various process steps in a method according to the invention. When multiple computer devices perform the entire operation, the computer devices are networked to distribute the various steps of the operation. The terms computer-readable medium or computer-usable medium are understood to comprise one or more physical embodiments of any type of program code. In particular, a computer-readable / usable medium may comprise program code embodied on one or more portable storage products (e.g., optical disks, magnetic disks, tapes, etc.) or on one or more data storage portions of computing devices such as memory associated with a computer and / or storage system.

[0067] If a mobile device includes links to access web services rather than its own applications, the mobile application of the present invention may be implemented as a web service. The described functionality can be implemented on any mobile platform, including the Android platform, iOS platform, Linux® platform, or Windows® platform. In further embodiments, the disclosure provides systems, devices, methods, and computer program products that include a set of non-temporary machine-readable instructions for use in implementing such methods and enabling the functionality described above.

[0068] In one respect, the present disclosure provides a cargo handling device designed to operate on top of an automated storage and retrieval system for cubes. The cargo handling device comprises two wireless antennas, each having its own wireless network interface. The cargo handling device can establish two simultaneous wireless communication links to different wireless access points. One of the links is used as a primary link for control of the cargo handling device, and the other link is used as a secondary link.

Claims

1. A cargo handling device for use in a storage system, comprising a first network interface and a second network interface, wherein the cargo handling device is configured to establish a first communication link to the storage system using the first network interface and to establish a second communication link to the storage system using the second network interface when in use.

2. The cargo handling device according to claim 1, wherein one of the first or second communication links is a primary communication link, and data transmitted and received via the first communication link is used to control the operation of the cargo handling device.

3. The cargo handling device according to claim 2, wherein the other of the first or second communication link is a secondary communication link, and the data transmitted and received via the secondary communication link is a copy of the data transmitted and received via the primary communication link.

4. The cargo handling device according to any one of claims 1 to 3, wherein the first communication link is between the first network interface and the first access point of the first access point group, and the second communication link is between the second network interface and the second access point of the first access point group.

5. The cargo handling device according to any one of claims 1 to 3, wherein the first communication link is between the first network interface and the first access point of the first access point group, and the second communication link is between the second network interface and the first access point of the second access point group.

6. The cargo handling device according to any one of claims 1 to 5, wherein the first communication link or the second communication link is made into a primary communication link according to one or more measured parameters.

7. The cargo handling device according to claim 6, wherein the primary communication link is transmitted between the first communication link and the second communication link according to one or more measured parameters.

8. The cargo handling device according to any one of claims 1 to 5, wherein the decision to make the first communication link or the second communication link the primary communication link is made according to the location of the cargo handling device in the storage system.

9. The cargo handling device according to claim 8, comprising a lookup table having data relating to the network status at each storage system location, wherein the network status data is used in determining whether the first communication link or the second communication link is the primary communication link.

10. The cargo handling device according to claim 8 or 9, wherein the primary communication link is transmitted between the first communication link and the second communication link according to the position of the cargo handling device in the storage system.

11. The cargo handling device according to claim 8 or 9, wherein the primary communication link is transmitted between the first communication link and the second communication link in accordance with the direction of movement of the cargo handling device within the storage system.

12. The cargo handling device according to any one of claims 1 to 5, wherein the decision to make the first communication link or the second communication link the primary communication link is made in accordance with data received by the cargo handling device from the storage system.

13. The cargo handling device according to claim 12, wherein the primary communication link is transmitted between the first communication link and the second communication link according to further data received from the storage system by the cargo handling system.

14. The cargo handling device according to any one of claims 1 to 13, wherein the cargo handling device is configured to change the first communication link and / or the second communication link to the storage system in response to receiving a control message from the storage system.

15. The cargo handling device according to claim 14, wherein the cargo handling device is configured to change the first communication link and / or the second communication link to different wireless access points within an existing group of access points.

16. The cargo handling device according to claim 14, wherein the cargo handling device is configured to change the first communication link and / or the second communication link to wireless access points in different access point groups.

17. A cargo handling device according to any one of claims 2 to 16, wherein if the primary communication link is lost, the secondary communication link is designated as the primary link, but the existing connection to the wireless access point is maintained.

18. The storage system comprises a first set of parallel tracks extending in the X direction and a second set of parallel tracks extending in the Y direction traversing the first set in a substantially horizontal plane, forming a grid pattern comprising a plurality of grid spaces and a plurality of stacks of storage containers located beneath the tracks, with each stack positioned within the footprint of a single grid space. The aforementioned cargo handling device is A wheel assembly arranged to move selectively in the X direction or the Y direction, A cargo handling device according to any one of claims 1 to 17, comprising: a container lifting device arranged to lift a container from one of the plurality of stacks into the cargo handling device when in use.

19. A storage system, A grid pattern comprising multiple grid spaces is formed in a substantially horizontal plane, comprising a first set of parallel tracks extending in the X direction and a second set of parallel tracks extending in the Y direction traversing the first set, Multiple stacks of storage containers located beneath the aforementioned track, arranged such that each stack is located within a single grid space footprint, A storage system comprising at least one cargo handling device according to any one of claims 1 to 18, wherein the at least one cargo handling device is positioned above the stack on the truck to move selectively in the X and Y directions and is positioned to transport storage containers.

20. The storage system according to claim 19, further comprising a picking station which receives a storage container transported by the at least one cargo handling device and is positioned to transport items from the storage container into a delivery container.

21. A communication network for use in a storage system, wherein the communication network comprises one or more wireless access point groups, and each of the or each wireless access point group comprises multiple wireless access points.

22. The communication network according to claim 21, wherein the communication network is configured to establish a first communication link to a cargo handling device via a first wireless access point and a second communication link to the cargo handling device via a second access point when in use.

23. The communication network according to claim 22, wherein the communication network is configured to establish the first communication link via wireless access points in a first wireless access point group when in use.

24. The communication network according to claim 22 or 23, wherein the communication network is configured to establish the second communication link via wireless access points in a second wireless access point group when in use.

25. The communication network according to any one of claims 22 to 24, wherein, when in use, the first communication link is used to transmit control signals and safety signals to the cargo handling device.

26. The communication network according to any one of claims 22 to 25, wherein, during use, the second communication link is a backup link in the event that the first communication link is lost.

27. A method for establishing a communication link between a storage system and one or more cargo handling devices operating within the storage system, wherein the storage system comprises a plurality of wireless access points, and the method is a) For each location within the storage system, the step of determining one or more parameter values ​​for each of the plurality of wireless access points mainly located at that location, b) A method comprising determining, for each location in the storage system, a preferred wireless access point for a cargo handling bot to be used for primary connection at that location, according to the one or more parameter values ​​determined in step a).

28. c) The method of claim 27, further comprising the step of determining, for each location in the storage system, one or more wireless access points for a cargo handling device to be used for secondary connections at that location, according to the one or more parameter values ​​determined in step a).

29. The method according to claim 27 or 28, wherein in step a), one or more parameter values ​​are measured, and the measurement is performed by one or more cargo handling devices.

30. The method according to claim 27 or 28, wherein in step a), the one or more parameter values ​​are calculated based on a theoretical model.

31. The method according to any one of claims 27 to 30, wherein one or more of the multiple cargo handling devices operating within the storage system periodically reports measured parameter values, and the reported measured parameter values ​​are used to update the parameter values ​​determined in step a).

32. The method according to any one of claims 28 to 31, wherein the one or more parameter values ​​are used to generate a lookup table that holds the one or more parameter values ​​for each position in the storage system.

33. The method according to any one of claims 27 to 32, wherein the lookup table is transmitted to one or more of a plurality of cargo handling devices operating within the storage system.

34. The method according to claim 33, wherein a portion of the lookup table is periodically transmitted to one or more of the plurality of cargo handling devices operating within the storage system.

35. The method according to claim 33 or 34, wherein the lookup table comprises identification information of one or more wireless access points suitable for supporting a primary connection for each location in the storage system.

36. The method according to any one of claims 33 to 35, wherein the lookup table comprises identification information of one or more wireless access points suitable for supporting secondary connections for each location in the storage system.

37. The method according to any one of claims 33 to 36, wherein the lookup table comprises identification information of one or more wireless access points that are not suitable for supporting a primary or secondary connection for each location in the storage system.

38. A data carrier device comprising computer executable code for performing the method according to any one of claims 27 to 37.

39. A storage system, A grid pattern comprising multiple grid spaces is formed in a substantially horizontal plane, comprising a first set of parallel tracks extending in the X direction and a second set of parallel tracks extending in the Y direction traversing the first set, Multiple stacks of storage containers located beneath the aforementioned track, arranged such that each stack is located within a single grid space footprint, At least one cargo handling device, the at least one cargo handling device is positioned above the stack on the truck to move selectively in the X and Y directions and to transport storage containers. A storage system comprising one or more wireless access point groups, wherein the storage system is configured to perform the method according to any one of claims 27 to 37 when in use.

40. The storage system according to claim 39, wherein the aforementioned or each wireless access point group comprises a plurality of wireless access points.

41. The storage system according to claim 39 or 40, wherein each cargo handling device has a footprint that occupies only a single grid space in the storage system, and a cargo handling device occupying one grid space does not interfere with a cargo handling device occupying or traversing an adjacent grid space in the X and / or Y direction.

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