Patent Application
20240262617
The present invention relates to the field of remotely operated load handling devices on tracks located on a grid framework structure for handling storage containers or bins stacked in the grid framework structure, more specifically to a grid framework structure for supporting the remotely operated load handling devices.
Storage systems comprising a three-dimensional storage grid structure, within which storage containers/bins are stacked on top of each other, are well known. PCT Publication No. WO2015/185628A (Ocado) describes a known storage and fulfilment system in which stacks of bins or containers are arranged within a grid framework structure. The bins or containers are accessed by load handling devices remotely operative on tracks located on the top of the grid framework structure. A system of this type is illustrated schematically in
As shown in
A majority of the grid columns are dedicated for the storage of storage containers (otherwise as ‘bins’ or ‘totes’) in stacks and therefore considered to be storage columns, to differentiate them from a port column. A grid framework structure typically has at least one grid column which is not used for the storage of storage containers in a stack, but is a location where the robotic load handling device can drop off and/or pick-up storage containers so that they can be moved to an access station where the contents of the storage containers can be accessed from outside of the grid framework structure. The location of the grid cell where a robotic load handling device can drop off/pick up a storage container is termed a ‘port’ and the grid column in which the port is located is termed a ‘port column’.
The top level of the grid framework structure 14 includes rails 22 arranged in a grid pattern across the top of the stacks 12. Referring additionally to
A known load handling device 30 shown in
The load handling device 30 is equipped with a lifting device or crane mechanism to lift a storage container from above. The crane mechanism comprises a winch tether or cable 38 wound on a spool or reel (not shown) and a grabber device 39. The lifting device comprises a set of lifting tethers 38 extending in a vertical direction and connected nearby or at the four corners of a lifting frame 39, otherwise known as a grabber device (one tether near each of the four corners of the grabber device) for releasable connection to a storage container 10. The grabber device 39 is configured to releasably grip the top of a storage container 10 to lift it from a stack of containers in a storage system of the type shown in
The wheels 34, 36 are arranged around the periphery of a cavity or recess, known as a container-receiving recess 40, in the lower part. The recess is sized to accommodate the container 10 when it is lifted by the crane mechanism, as shown in
One significant drawback of the prior art systems are that they can only use containers of one specified footprint. In addition, the height of the containers is often constrained by the design of the robotic load handlers. This typically constrains the use of such systems to such items which fit inside the containers. In typical applications, this means that 1-10% of the total volume of goods in the storage system needs a different handling method, typically manual. This means added complexity in the system, low productivity and inefficient use of space. WO2015/197709 (Ocado Innovation Limited) attempts to address this problem by providing a grid framework structure having different sized grid cells that is configured to accommodate different sized storage containers. Thus, larger items that cannot be stored in the smaller storage containers can be stored in larger storage containers and the smaller items can be stored in the smaller storage containers. Different sized load handling devices are operable on the grid and are able to move the different sized storage containers.
Restricting a portion of the grid to accommodate larger storage containers reduces the packing density for the storage of smaller items, which account for bulk of the fulfilled orders. Thus, the storage capacity of the grid framework structure may become compromised should there be an increase in demand for the smaller items that are able to be stored in the smaller storage containers. A grid framework structure is thus required that is flexible to store larger items and smaller items, but which does not compromise the storage capacity of the grid framework structure.
The access station may typically be used as a picking station, where one or more items are removed from the storage containers delivered to the picking station, or a stocking ‘decant’ station, where one or more items are placed in the storage containers to replenish stock. When the contents of the storage container are requested, a robotic load handling device operative on the grid is instructed to move to a grid location where the target storage container is located and retrieve the target storage container using the lifting device of the robotic load handling device. The target storage container is transported to a drop-off port in the grid where it is lowered through a port column to a drop-off area. At the drop-off area, the target storage container is transported to the access station. At the access station, one or more items are picked from the storage container. Once the contents of the storage container are retrieved from the container at the access station, the storage container is transported to a pick up station where the storage container is subsequently picked up by a robotic load handling device and either returned to its original storage location or a new storage location. A conveyor system comprising conveyors is typically used to transport the storage containers to the access station from the drop-off area when dropped off from the port column.
The rate at which the items are picked from the storage containers at the access station is dependent on the number of storage containers at the access station, which in turn is dependent on how fast the storage containers can be conveyed to the access station and exit the access station. In some circumstances, one or more storage containers are held in a queue at the access station waiting to be transported to the pick-up area and subsequently picked-up by a robotic load handling device operable on the grid. WO2018/233886 (Autostore Technology AS) tries to address this problem by providing a container handling station comprising a horizontal container carousel comprising a first straight conveyor section and a second straight conveyor section interconnected by two intermediate conveyor sections. Each of the conveyor sections comprises at least one conveyor device for accommodating and moving a container in a horizontal direction. The first straight conveyor section (25) is arranged directly below multiple port columns (19,20), such that any of the container handling vehicles (9) may transfer a container (6) between the top level of the grid and the first straight conveyor section (25) via any of the multiple port columns (19, 20). The second straight conveyor section (26) is arranged to allow access to a container (6) retrieved from the grid (4) via the first straight conveyor section (25). The container handling station is too complicated and requires multiple moveable parts to transport the storage container around the carousel. Moreover, the rate limiting step in processing the storage containers at the access station is dependent on how fast the storage containers can be transported around the carousel. In a majority of cases, an operator at the access station is left waiting until the storage containers at the access station is processed (i.e. items picked). Increasing the speed of the carousel to move the storage containers through the access station is limited by the speed at which the processed storage containers can be picked up from the pick-up area.
The present invention has mitigated the above problem by providing an inventory handling station assembly comprising a plurality of access stations that are vertically spaced at different levels or heights so that more storage containers can be presented to an operator or a robotic picking device at the inventory handling station assembly. The storage containers are arranged at different heights so that the operator can easily reach into the storage containers at the different levels and pick the items from the storage containers. In comparison to presenting the storage containers at the same level, having the storage containers presented to the operator at different heights increases the speed by which the operator can reach into and pick items from the storage containers since more of the storage containers are presented to an operator at any one time. Thus, the present invention provides a storage and retrieval system comprising:
A plurality of upright columns can be arranged to form the plurality of storage columns for one or more of the storage containers to be stored in vertical stacks between and to be guided by the plurality of upright columns in a vertical direction. The upper level port column is arranged to drop off/pick up storage containers into and out of the first access station at a first level, and the lower level port column is arranged to drop off/pick up storage containers into and out of the second access station at a second level, the second level being below the first level. The upper level port column can be a vertical chute having a first opening for receiving a storage container lowered by at least one robotic load handling device operable on the track system through a grid cell and a second opening to allow the storage container to enter the first access station at the first level. Similarly, the lower level port column through which the storage containers can transferred between the track system and the inventory handling station assembly can be a vertical chute such that a robotic load handling device operative on the track system can drop off and/or pick up a storage container to or from the second access station at the second level. Alternatively, the upper level and/or the lower level port column can comprise a storage container lifting or lowering device through which the storage container can be automatically transferred between the track system and the first and second access station respectively.
To increase the visibility of the contents of the vertically spaced storage containers at the first and second access station, optionally the first access station is laterally offset from the second access station. To limit the footprint of the inventory handling station assembly, optionally the first access station at least partially overlays the second access station. Each level of the first and second level of the inventory handling station assembly is divided or segregated so that preferably, the first level of the inventory handling station assembly comprises a drop-off area and a pick-up area arranged below the upper level port column for transferring storage containers between the track system and the drop-off and the pick-up area at the first level; and the second level of the inventory handling station assembly comprises a drop-off area and a pick-up area arranged below the lower level port column for transferring storage containers between the track system and the drop-off and the pick-up area at the second level. For the purpose of definition, the term ‘drop-off area’ can sometimes be referred to ‘drop-off station’ and the term ‘pick-up area’ can sometimes be referred to ‘pick-up station’. As a result, the terms ‘drop-off station’ and ‘drop-off area’ can be used interchangeably in the patent specification to mean the same feature. Equally, the terms ‘pick-up area’ and ‘pick-up station’ can be used interchangeably in the patent specification to mean the same feature. Optionally, the upper and lower level port columns comprise a drop-off port column for allowing storage containers to be lowered from the track system to the drop-off area and a pick-up port column for allowing storage containers to be picked up from the pick-up area towards the track system. The upper and lower level port columns are configured with a drop-off port column through which a storage container can be dropped off to the respective drop-off area at the first level and the second level of the inventory handling station assembly. Similarly, the upper and lower port columns are configured with a pick-up port column through which a storage container can be picked up from their respective pick-up area at the first and second level of the inventory handling station assembly.
In order for the drop-off port column and the pick-up port column of the upper level port column and the lower level port column to drop off and pick up storage containers to and from the respective drop-off area and the pick-up area at the first level and the second level, preferably, the drop-off area at the first level is laterally offset from the drop-off area at the second level. Similarly, preferably the pick-up area at the first level is laterally offset from the pick-up area at the second level. As a result, the drop-off and pick-up areas at each of the first and second level are arranged below their respective upper level port column and lower level port column. The drop-off and pick-up areas at the first level being laterally offset from the drop-off and pick-up areas at the second level enables the drop-off port columns and the pick-up port columns of the upper and the lower level port columns to drop off and pick up storage containers directly to or from their drop-off and pick-up areas respectively.
To convey storage containers from the drop-off area to the pick-up area via the access station where the storage container is paused to enable the contents to be picked from or decanted into the storage containers at each of the first and second level of the inventory handling station assembly, preferably the first level comprises a first conveyor system configured to convey one or more storage containers from the drop-off area to the pick-up area via the first access station, and the second level comprises a second conveyor system configured to convey one or more storage containers from the drop-off area to the pick-up area via the second access station.
More preferably, each of the first and second conveyor systems comprises an entry conveyor unit, an exit conveyor unit, and at least one access conveyor unit, wherein the entry conveyor unit is arranged in the drop-off area and arranged to transport a storage container in a first transport direction from the drop-off area to the first or second access station,
The at least one access conveyor unit is configured to pause a storage container at the access station in order for items to be picked from or decanted into the storage container prior to the storage container being conveyed to the pick-up area.
To conserve space, and thus the footprint of the inventory handling station assembly, optionally the entry conveyor unit and the exit conveyor are arranged such that the first transport direction of the entry conveyor unit is opposite and parallel to the second transport direction of the exit conveyor unit, and the third transport direction of the at least one access conveyor unit is orthogonal to both the first transport direction of the entry conveyor unit and the second transport direction of the exit conveyor unit. In other words, the storage containers travel in a substantially “U” shaped direction from the drop-off area to the pick-up area via the access station. Alternatively, the conveyor system can be arranged such that the first transport direction of the entry conveyor unit is substantially orthogonal to both the second transport direction of the exit conveyor unit and the third transport direction of the at least one access conveyor unit such that the storage containers travel in a substantially ‘L’ shaped direction from the drop-off area to the pick-up area via the access station.
In the case where one or more items are required from a target storage container located deep within a stack of storage containers in a storage column, i.e. a plurality of storage containers are positioned above a target storage container in the storage column, it is necessary that one or more storage containers above the target storage container would need to be temporarily moved in order for a robotic load handling device operative on the track system to access the target storage container. This process of accessing a target storage container within a stack in a storage column is known in the industry as “digging”. The process of digging a target storage container from a stack of storage containers in a storage column can be performed by the same robotic load handling device that is subsequently used to move the target storage container to the drop-off port, or by a plurality of robotic load handling devices that work together with one robotic load handling device instructed to remove one or more storage containers from the target storage container and another robotic load handling device to remove the target storage container for delivery to the inventory handling station assembly via the drop-off port. The removed storage containers from the stack can be repositioned in the original storage column, or alternatively, relocated to another storage column. The process of ‘digging’ a target storage container from a stack in a storage column is both time consuming and requires at least one additional operation in order to access the target storage container.
To present invention has mitigated the problem of digging by providing a second track system arranged above a second plurality of storage columns, so that the storage containers can be spread out through different areas of the grid framework structure, reducing the need to dig out storage containers. For example, the storage containers can be divided out into a first or a second plurality of storage columns so that the more frequently requested storage containers are in one area of the grid framework structure and the other area of the grid framework structure is arranged to store the less frequently requested storage containers. More specifically, the grid framework structure further comprises:
For the purposes of this description, the track system will be referred to as a first track system. Another benefit of segregating the grid framework structure into a first area comprising the (first) track system and a second area comprising the second track system is an increase in the throughput of storage containers to the inventory handling station assembly as the different areas of the grid framework structure comprising the first and second track systems respectively are able to take advantage of the multiple access stations at the different levels of the inventory handling station assembly. Like the first track system, the second upper level port column extends from the second track system to the first access station at the first level for transferring storage containers between the second track system and the inventory handling station assembly; and the second lower level port column extends from the second track system to the second access station at the second level for transferring storage containers between the second track system and the inventory handling station assembly. As discussed above, the second upper level port column can be a vertical chute having a first opening for receiving a storage container lowered by at least one load handling device operable on the second track system through a grid cell, and a second opening to allow the storage container to enter the first access station at the first level. Similarly, the second lower level port column through which the storage containers can be transferred between the second track system and the inventory handling station assembly can be a vertical chute such that a robotic load handling device operative on the track system can drop off and/or pick up a storage container from the second access station at the second level.
In an example where the track system is arranged vertically above the second track system and to accommodate the upper and lower level port columns of both track systems (track and second track systems), optionally, at least a portion of the track system (first track system) overhangs the second track system. As a result, the at least portion of the track system overhanging the second track system comprises the upper level port column for transferring storage containers between the track system and the first access station of the inventory handling station assembly and/or the second lower level port column for transferring storage containers between the track system and the second access station of the inventory handling station assembly. In this way, a robotic load handling device operable on the track system (first track system) is able to transfer storage containers directly to the first and/or second access stations at the different levels of the inventory handling station assembly via their respective upper level port column and lower level port column without the need to extend through one or more grid cells of the second track system below. Alternatively, the upper and/or lower level port columns from the track system can extend through the one or more grid cells of the second track system to transfer one or more storage containers to the first and second access stations of the inventory handling station assembly via their respective upper and lower level port columns. A robotic load handling device operable on the second track system is able to transfer storage containers to the first and second access stations of the inventory handling station assembly via their respective upper level port column (second upper level port column) and lower level port column (second lower level port column). In other words, both the track system and the second track system can share the same or have a common inventory handling station assembly due to having at least a portion of the upper track system overhanging the second track system to enable a robotic load handling device having access to the inventory handling station assembly below. An additional benefit of the first and second track systems at different levels is that they offer a neat and compact way of bringing both chilled and ambient items to the same inventory handling station assembly. For example, the different areas of the grid framework structure comprising the first and second track systems respectively can be arranged with separate chilled and ambient areas of the grid framework structure. The different areas of the grid framework structure can be increased to include a third area comprising a frozen section. For the purpose of definition, the ambient area covers temperatures in the range 21° C. to 50° C., chilled temperatures covers the temperature range 2° C. to 8° C. and the freezer temperatures cover the temperature range −21° C. to −16° C. Additionally, the plurality of tracks can be arranged such that the track system and/or the second track system comprises:
The small cell portion comprises a first set of parallel tracks extending in a first direction and a second and third sets of parallel tracks extending in a second direction, the second direction being substantially perpendicular to the first direction. The first, second and third sets of parallel tracks being arranged in a grid pattern to define a first set of grid cells, each grid cell of the first set of grid cells having a dimension extending in the first direction and a dimension extending in the second direction to define a first type grid cell opening. The large cell portion comprises a second set of grid cells, the second set of grid cells being defined by the first and second sets of parallel tracks, each grid cell of the second set of grid cells having a dimension extending in the first direction and a dimension extending in the second direction to define a second type grid cell opening. In the first direction, the dimension of the second type grid cell opening is a multiple of the dimension of the first type grid cell opening, and in the second direction, the dimension of the first type grid cell opening is substantially equal to the dimension of the second type grid cell opening. The multi-cell sizes of the track system and/or the second track system provide different grid cell openings through which different sized storage containers can exit or be lowered through the grid cell. The different sized storage containers can be used to store different sized items, and thereby increase the flexibility to extend the storage facility of the storage and retrieval system of the present invention to general merchandise. The plurality of parallel sets of tracks can be arranged such that either the first or second track systems comprise the first and second sets of grid cells or both the first and second track systems comprise the first and second sets of grid cells. Alternatively, the track system comprises both the first and second sets of grid cells and the second track system comprises the first set of grid cells. To enable a robotic load handling device to move on the track system and the second track system, the storage and retrieval system further comprises:
Further features and aspects of the present invention will be apparent from the following detailed description of an illustrative embodiment made with reference to the drawings, in which:
As shown in
The rail or tracks are typically profiled to guide a load handling device on the grid structure and are typically profiled to provide either a single track surface so as to allow a single load handling device to travel on the track or a double track so as to allow two load handling devices to pass each other on the same track. In the case where the tracks are profiled to provide a single track, the track comprises opposing lips (one lip on one side of the track and another lip at the other side of the track) along the length of the track to guide or constrain each wheel from lateral movement on the track. In the case where the profile is a double track, the track comprises two pairs of lips along the length of the track to allow the wheels of adjacent load handling devices to pass each other in both directions on the same track. To provide two pairs of lips, the track typically comprises a central ridge or lip and a lip either side of the central ridge.
The first and second sets of parallel tracks arranged in a grid pattern define a set of grid cells, each grid cell comprising a grid opening or grid spacing through which one or more storage containers can pass through the grid opening. The containers are generally rectangular in shape having a length longer than its width.
In a typical grid framework structure, the size of each of the grid openings is uniform throughout the track system so as to accommodate a uniform sized storage container. As a result, the footprint of the robotic load handling defined by the wheel assembly of the robotic load handling device, comprising a first set of wheels and a second set of wheels which are able to engage with the first set of parallel tracks for movement of the robotic load handling device in the first direction and the second set of parallel tracks for movement of the robotic load handling device in the second direction.
One or more stacks of storage containers are arranged below the respective grid openings of the track system, so that a robotic load handling device operative on the track system can drop off and/or pick up a storage container from a stack. The track system is raised above ground level by being mounted to the plurality of upright columns 116 at the intersections or nodes 58 where the grid members 118, 120 cross so as to form a plurality of vertical storage locations 60 for the storage containers to be stacked between the upright columns 116 and be guided by the upright columns 116 in a vertical direction through the plurality of substantially rectangular frames 54. For the purpose of the present invention, a stack of containers can encompass a plurality of containers or one or more containers in a stack. The grid framework structure 114 can be considered as a rectilinear assemblage of upright columns 116 supporting the track system 50 formed from intersecting horizontal grid members 118, 120, i.e. a four wall shaped framework. Two or more of the upright columns can be braced by at least one diagonal bracing member to increase structural stability of the grid framework structure 114. For the purpose of the present invention, the terms “vertical upright column”, “upright column” and “upright member” are used interchangeably through the description. For the purpose of explanation of the present invention, the intersections 58 constitute nodes of the grid structure.
The upright columns 116 are spaced apart as shown in
In the particular embodiment of the present invention, each of the guides 72 is shown as V-shaped or has a 900 cross-sectional profile that is shaped to butt up against or accommodate the corner profile of the storage containers, which are generally rectangular in shape. As shown in
At least a portion of the plurality of the upright columns 116 are held in space relation with each other in the grid framework structure by one or more spacers or struts 74 connected between adjacent upright columns 116 (see
The spacers 74 are sized to fit between the corner sections comprising the guides 72 of the upright column 116 so as to allow the upright columns to accommodate a stack of containers between the adjacent upright columns 116, i.e. the spacers do not impede or cross the area (or vertical storage location) occupied by the guides 72 or guiding plates at the corners of the upright column. One or more spacers/struts 74 are distributed in spaced apart relation along the length of two adjacent upright columns 116 in the grid framework structure (see
Upon receipt of an order, a robotic load handling device operative to move on the tracks is instructed to pick up a storage container containing the item to fulfil the order from a stack in the grid framework structure and transport the storage container to an inventory handling station assembly whereupon the item can be retrieved from the storage container and transferred to one or more delivery containers. The term ‘robotic load handling device’ is sometimes referred to as a ‘bot’ and such terms are used interchangeably throughout the description to mean the same feature. Typically, the inventory handling station assembly comprises a container transport assembly to transport one or more storage containers to an access station where the contents of the containers can be accessed. The container transport assembly is typically a conveyor system comprising multiple adjacent conveyor units. Further detail of the inventory handling station assembly is discussed below.
A typical layout of a fulfilment centre for fulfilment of an order comprises two distinct grid areas known as an ambient grid area and a chill grid area. Each of the ambient grid area and the chill grid area comprises a grid framework structure, i.e. the ambient grid area comprises a first grid framework structure and the chill grid area comprises a second grid framework structure. The ambient grid area stores food and grocery commodities at an ambient controlled temperature. The ambient controlled temperature covers a range between substantially 4° C. to substantially 21° C., preferably substantially 4° C. to substantially 18° C. Likewise, the chill grid area stores food and grocery commodities at a chilled temperature. The chilled temperature covers a range between substantially 0° C. to substantially 4° C. The two grid areas—ambient and chill—are filled with containers (otherwise known as storage containers, totes, or bins) containing various grocery products. Storage containers or bins storing commodity and grocery items are transported by load handling devices operative on the grid to a pick station or pick area in the pick aisle, where one or more items are picked from the storage bin or container at the pick station or pick area and transferred to one or more delivery containers.
Depending on the type of item, each of the one or more items will be classified with a particular SKU or stock keeping unit. As is commonly known in the art, a SKU or stock keeping unit is used by retailers to identify and track its inventory or stock. A SKU is a unique code consisting of letters and numbers that identify characteristics about each item, such as manufacturer, brand, style, colour and size. This can be recorded in a barcode. The characteristic SKU of the items and the identification of the storage bin is stored in an inventory database which is accessible by a control system or storage control and communication system. When stocking the storage system with items or replenishing the inventory of the storage system, items delivered from a supplier are transported to a decant station or a supply station. Here, the items are removed from their packaging and depending on the type of item, registered with a unique stock keeping unit or SKU, and placed in storage bins at the decant station. At the decant station, the storage bins are transported to a bin lift device whereupon they are lifted to the track system at grid level to be retrieved by a load handling device and transported to a location within the grid framework structure. Typically, a particular SKU is dedicated to a storage container and there is little or no mixing of SKUs within a single storage container. As a result, one or more storage containers are dedicated to a particular SKU.
As the grid framework structure provides the ability to densely store storage containers, the size of the items in storage is very much limited by the size of the storage containers. The size of a storage container is given by its length×width×depth. A typical standard storage container is of approximately of size 600 mm×400 mm×350 mm. Whilst most grocery items are able to be accommodated within the storage containers, this cannot be said for some non-grocery items, e.g. electrical items or clothing. For a fulfilment system offering general merchandise, the grid framework structure may be required to store items that may not be able to be stored in a standard sized storage container. As a result, different sized storage containers would be required to store the larger items and this adds a new level of complexity to the grid framework structure and the robotic load handling devices operating on the track system. Even if larger storage containers are provided in the grid framework structure as taught in WO2015/197709 (Ocado Innovation Limited), there is little or no flexibility to convert the larger storage containers into smaller storage containers should there be a shift in consumer buying habits. Typically, 1-10% of the total sales volume in the retail of general merchandise represents large items and this can vary throughout a given year. One or more dedicated robotic load handling device having a bigger footprint than the footprint of the robotic load handling devices operating on the smaller grid cells are able to access the large storage containers below the bigger grid cells. Dedicating a proportion of the grid framework structure for the storage of large items reduces the effectiveness of the grid framework structure to increase the storage capacity for storing smaller items without mixing the SKUs in a single large storage container. Even if multiple different SKU items are stored in a single large storage container, it would be necessary for a robotic load handling device operating on the larger grid cells to pick up the entire storage container containing the unwanted SKU items from its storage column and transport it to a pick station. Either way, this represents a less efficient way to store items in the grid framework structure and removes the flexibility of the grid framework structure to vary the proportion of large and small grid cells.
Additionally, in the case where a majority of the items in storage occupy a relatively small fractional volume of a standard storage container, the remaining volume of the storage container is unused. As the storage containers are typically of a standard size and considering that hundreds or even thousands of storage containers are densely packed within a typical storage and retrieval system comprising the grid framework structure, the accumulation of this free space from multiple storage containers in storage can represent a relatively large proportion of the storage volume of the grid framework structure.
The present invention shown in
The second portion 226 of the track system comprises a combination of the first set of grid cells 228 and a second set of grid cells 230. Unlike the first set of grid cells 228, the second set of grid cells 230 are defined by only the first 218 and the second 220 sets of parallel tracks, whereby each grid cell 230 of the second set of grid set of grid cells has a dimension extending in the first direction and a dimension extending in the second direction to define a second type grid cell opening 54c. The third set of parallel tracks 220 divides the second type grid cell openings 54c to create the first set of grid cells 228. In the particular embodiment of the present invention shown in
In order for a robotic load handling device having a wheel assembly with a different footprint to move across both the first 54b and the second 54c type of grid openings, the dimension in one direction of the first and second type of grid openings are substantially equal. More specifically, in the first direction, the dimension of the second type grid cell opening 54c is a multiple of the dimension of the first type grid opening 54b and in the second direction, the dimension of the first type grid opening is substantially equal to the dimension of the second type grid opening. The wheel assembly of a robotic load handling device is tailored so that the separation of sets of pairs of wheels are able to engage with the first, second and third sets of parallel tracks when moving in the first and the second direction. This can be explained with reference to
The wheel assembly of a robotic load handling device can be described with respect to the wheel base and track width as shown in
For a wheel assembly having a different wheel base to move on the tracks so as to straddle across the first type (small) 54b and the second type (large) grid 54c openings, the track width of the wheel assembly is an important aspect of the wheel assembly. The track width, as demonstrated in
To accommodate a larger (second) type storage container in the track system, the second track width ‘F’ of the second set of wheels 236 of the large robotic load handling device is a multiple of the second track width ‘D’ of the second set of wheels 136 of the small robotic load handling device. The differences in dimension of the first and second track widths of the wheel assemblies of the small and large robotic load handling device is shown in
In operation, the smaller first type of robotic load handling device 30b is able to enter the second portion 226 of the track system via the smaller first type grid cell 228 in one direction, i.e. the second direction, such that its wheel assembly is able to straddle across the large second type grid opening 54c. In other words, the track width of its wheel assembly extends across the width of the larger second type grid cell 230. In the particular embodiment shown in
Since the first type robotic load handling device entered the second portion of the track system in a second direction, then it is able to move across the larger second type grid cell in the first direction. The movement of the first type robotic load handling device from the first portion 224 of the track system 214 into the second portion 226 of the track system and across the larger second type grid cells 230 is demonstrated by the dashed arrows shown in
One or more stacks of the different sized storage containers (e.g. first and second type) are arranged below their respective grid cell openings (first and second type) in the first, second and optionally, the third portion of the track system so that the first type and the second robotic load handling devices operative on the track system can drop off and/or pick up a storage container from a stack (see
To enable the smaller, first type robotic load handling device 30b to lift items from the larger, second type storage container when straddled over the second (larger) type grid cell opening 54c, two or more of the smaller, first type storage containers 110 can be nested within the larger, second type storage container (see
There are different arrangements of the smaller, first type storage containers that can be nested in the larger, second type storage container as demonstrated in
The ability to nest the smaller storage containers 110a, 110b in the larger storage containers 111 increase the flexibility by which the grid framework structure can store items of varying sizes, as the larger storage containers 111 can be used to accommodate the smaller storage containers 110a, 110b. For example, one or more of the larger storage containers 111 in the larger, second type storage columns 215 in the grid framework structure shown in
Optionally, one or more of the larger storage containers 111 comprising the nested smaller storage containers 110a, 110b can be moved to a storage location by a large bot 30c to the second type storage columns 215 below the third portion 328 of the track system 314. The third portion 328 of the track system 314 comprising largely the large grid cells 230 allows the storage and retrieval system of the present invention to provide a separate storage area for the large storage containers 111. The large storage containers 111 below the third portion 328 of the track system 314 can be used to store large items or can comprise the smaller storage containers 110a, 110b nested within the larger storage containers 111 for the storage of smaller items. This increases the capacity of the storage and retrieval system of the present invention to store the smaller items should there be a need to extend the storage capacity of smaller items beyond the stacks of storage containers below the first portion 224 of the track system.
A typical layout of a storage and retrieval system 401 comprising a grid framework structure 402 supporting the track system 414 of the present invention is shown in
A majority of the grid columns in the grid framework structure 402 are storage columns, i.e. grid columns where storage containers are stored in stacks. However, a grid normally has at least one grid column which is used not for storing storage containers, but which comprises a location where the bots can drop off and/or pick up storage containers so that they can be transported to a location (not shown in the prior art figures) where the storage containers can be accessed from outside of the grid framework structure or transferred out of or into the track system. Within the art, such a location is normally referred to as a “port” and the grid column in which the port is located may be referred to as a “port column” through which the storage containers can be transferred between the top level of the track system and the inventory handling station assembly. The grid framework structure can comprise a single port column through which the storage containers can be delivered (dropped off) or retrieved (picked up) from the inventory handling station assembly or alternatively can comprise two port columns. The first port column may for example comprise a dedicated drop-off port where the bots can drop off storage containers to be transported through the first port column and further to an access or a transfer station of the inventory handling station assembly, and the second port column may comprise a dedicated pick-up port where the bots can pick up storage containers that have been transported through the second port column from an access or a transfer station. Storage containers are fed into the access station and exit the access station via the first port column and the second port column respectively. The first and second port column can be separate port columns for the drop off and pick up of storage containers respectively or a single port column for the drop off and pick up of storage containers. In the particular embodiment of the present invention shown in
Dedicated drop-off/pick-up port columns 406, 408, 410 are provided in the grid framework structure 402 for the smaller storage containers and the larger storage containers. These can be termed a first type port column 406, 408 through which the smaller storage containers can be transferred between the drop-off/pick-up port of the track system and the inventory handling station assembly 404, and a second type port column 410 through which the larger storage containers 111 can be transferred between the drop-off/pick-up port of the track system and the inventory handling station assembly 404. Each of the first type port column 406, 408 and/or the second type port column 410 comprises a drop-off port column through which the first type storage container and/or the second type storage container is lowered to the inventory handling station assembly and a pick-up port column through which the first type and/or second type storage container is picked up towards the track system. These can be separate port columns or a single port column for the drop off and pick up of storage containers. In the particular embodiment of the storage and retrieval system shown in
When the contents of a storage container in the grid framework structure are to be accessed, depending on the size of the storage container in storage, the smaller bot or larger bot is instructed to retrieve the target storage container from its position in the grid framework structure. The operation involves moving the relevant bot from its position on the track system to a grid location above the storage column in which the target storage container is positioned, picking up the storage container from its storage column using the bot's lifting device, and moving the storage containers to the drop-off port. The relevant bot depends on whether the target storage container is the smaller storage container, in which case the smaller bot is instructed to retrieve the target storage container, or the large storage container, in which case the larger bot is instructed to retrieve the target storage container. When a storage container is to be stored in the grid framework structure, depending on the size of the storage container, the relevant bot is instructed to pick up the storage container from the pick-up port and move it to a grid location in the track system above a storage column where it is lowered to be stored.
A single inventory handling station assembly 404 or separate inventory handling station assemblies can be provided for handling the smaller storage containers and the larger storage containers that are transferred from the respective drop-off/pick-up port columns of the first type port column 406, 408 and the second type port column 410. Typically, the inventory handling station assembly 404 known in the art comprises a port station or drop-off area 416 which cooperates with the drop-off port column 406 to receive storage containers, a pick-up area 418 which cooperates with the pick-up port column 408 through which storage container can be picked up towards the track system, and an access station 420 where the contents of the storage containers can be accessed. As shown in
The access station 420 of the inventory handling station assembly 404 of the present invention can double up as a supply station or decant station wherein inventory stored in the grid framework structure is replenished with fresh stock. A conveyor system 422 is configured to convey storage containers from the drop-off area 416 to the pick-up area 418 via the access station 420. The conveyor system 422 is configured such that storage containers are paused at the access station 420 for a predetermined amount of time to enable an operator 424 or a robotic arm to reach into and pick items from the storage containers at the access station 420. The conveyor system 422 can comprise an entry conveyor unit, an exit conveyor unit and at least one access conveyor unit, the entry conveyor unit being arranged in the drop-off area 416 and arranged to transport a storage bin or container dropped off from the drop-off port column 406 in a first transport direction to the at least one access conveyor unit. The exit conveyor unit is arranged in the pick-up area 418 and arranged to transport a storage bin or container from the at least one access conveyor unit to the pick-up area in a second transport direction, and the at least one access conveyor unit is arranged to transport a container from the drop-off area to the pick-up area in a third transport direction. Each conveyor unit may comprise any suitable arrangement of belt(s), chain(s) and/or rollers well known in the art of conveyor systems. Typically, one or more of the rollers of the at least one access conveyor unit and optionally, the entry conveyor unit and/or exit conveyor unit comprises an integrated driving motor (not shown), whilst the remaining rollers may be connected by belts (not shown) to the driving roller, or they may be passive. The entry conveyor unit and the exit conveyor unit are arranged such that the first transport direction of the entry conveyor unit is opposite and parallel to the second transport direction of the exit conveyor unit and wherein the third transport direction of the at least one access conveyor unit is orthogonal to both the first transport direction and the second transport direction of the entry conveyor unit and the exit conveyor unit respectively, i.e. U shaped trajectory (see
However, the rate limiting step of the throughput of storage containers through the storage and retrieval system is the ability of the storage containers to be processed, in the sense that one or more items can be picked or decanted into the storage containers at the access station. Known inventory handling station assemblies in the art suffer from the problem of presenting a limited number of storage containers at the access station. The present applicant has realised that an operator can pick from or decant one or more items into the storage containers much faster than the number of storage containers presented to the operator at the access station shown in FIG. 15. As a result, the access station becomes a bottleneck as the storage containers wait to be processed through the inventory handling station assembly. With the increasing development of automated picking and/or decanting systems such as robotic arms with the ability to pick and/or decant items at a faster rate than a human being, the bottleneck at the access station is becoming an increasing problem. Typically, the pick rate at the access station of known inventory handling station assemblies is around 400 items per hour, and some automated systems can pick in excess of 1000 items per hour. Attempts have been made to speed up the movement of the storage containers through the access station in order to increase the throughput and in some cases a carousel is used to move the storage containers through the access station at a faster rate as taught in the art, WO2018/233886 (Autostore Technology AS). Speeding up the movement of the storage containers through the access station just shifts the problem to the exit station, where one or more storage containers become accumulated waiting to be either lifted towards the track system for subsequent retrieval by a robotic load handling device operative on the track system, or retrieved by a robotic load handling device operative on the track system.
The present invention has mitigated this problem by providing an inventory handling station assembly 504 wherein the access station 520b, 520c is formed at two vertically spaced levels, namely a first access station 520b at a first level and a second access station 520c at a second level, the first level being vertically spaced from the second level (see
To enable an operator or robotic device to reach into the storage containers at the different levels, the first access station 520b is laterally displaced or offset from the second access station 520c such that the storage containers at the different levels are arranged in a step fashion. The lateral displacement of the storage containers at the first and second access station improves the presentation of the interior space of the storage containers to an operator or robotic device enabling the operator or robotic device to reach into the storage containers at the different levels (see
Also shown in
To prevent the first drop-off port column 506a clashing with the second drop-off port column 506b when dropping off a storage container to the drop-off area at the first level, the drop-off area 516a at the first level is laterally offset from the drop-off area 516b at the second level, i.e. set back from each other. In this way, the first drop-off port column 506a is able to cooperate with the drop-off area 516a at the first level and the second drop-off port column 506b is able to cooperate with the drop-off area 516b at the second level. Similarly, the pick-up area 518a at the first level is laterally offset from the pick-up area 518b at the second level. In this way, the first pick-up port column 508a is able to cooperate with the pick-up area 518a at the first level and the second pick-up port column 508b is able to cooperate with the pick-up area 518b at the second level. The first drop-off port column 506a and the second drop-off port column 506b are then able to feed storage containers to the first and second access stations 516a,b at the different levels at a much faster rate than if a single access station is used at one level. Similarly, the first 508a and second 508b pick-up port columns are able to transfer the storage containers into the grid framework structure so increasing the rate of movement of the storage containers through the first and second access stations at the different levels. However, the present invention is not limited to two access stations as shown in
To locate a storage container buried deep within a stack, it is necessary to instruct a robotic load handling device operative on the track system to remove one or more storage containers above the target storage container so that the target storage container is exposed for a robotic load handling device to lift the target storage container from its storage column. This operation is commonly known in the art as “digging”. The operation can be performed by the same robotic load handling device operative on the grid framework structure or a separate robotic load handling device specifically assigned to ‘dig” one or more storage containers from the target storage container for a subsequent robotic load handling device to retrieve the target storage container. The operational time to ‘dig’ a target storage container from a stack can represent a significant portion of the time to process the target storage container, which would involve moving the target storage container to an inventory handling station assembly and then returning the target storage container to the grid framework structure. The target storage container can be returned to its original location in a storage column or repositioned to a new location or new storage column.
To overcome or reduce the problem of “digging”, the grid framework structure according to the present invention comprises a second track system 614 as shown in
In the particular embodiment shown in
The portions of the grid framework structure comprising the first 212, 215 and the second 615 plurality of storage columns can optionally be designated to different temperature zones, e.g. ambient, chilled and/or frozen zones. For the purpose of the present invention, frozen temperature covers a range between substantially −25° C. to substantially 0° C., more preferably between substantially −21° C. to substantially −18° C.; the chilled temperature covers a range between substantially 0° C. to substantially 4° C., and the ambient controlled temperature coves a range between substantially 4° C. to substantially 21° C., preferably substantially 4° C. to substantially 18° C. The first plurality of storage columns can be designated for the storage of items that require a chilled environment and the second plurality of storage columns can be designated for the storage of items that require an ambient environment or vice versa. This is particularly important when fulfilling orders that are generally small comprising up to ten items, as is common in small convenience stores. Combining the chilled and the ambient zones into a single grid framework structure having a portion for the chilled zone and a portion for the ambient zone enables the grid framework structure to accommodate items necessary to fulfil such small orders.
One or more robotic load handling devices 30b,c operative on the second track system 614 can be controlled by the same or a separate controller instructing the robotic load handling devices on the first track system. One or more of the robotic load handling devices remotely operable on the first track system and second track system is configured to receive instructions from a master controller to a retrieve a storage container from a particular storage location within the grid framework structure. Wireless communications and networks may be used to provide the communication infrastructure from the master controller via one or more base stations to the one or more robotic load handling devices operative on the first and second track system. A controller in the robotic load handling device in response to receiving the instructions is configured to control various driving mechanisms to control the movement of the robotic load handling device. For example, the robotic load handling device may be instructed to retrieve a container from a storage column at a particular location on the first track system and/or second track system. The instruction can include various movements in an X-Y direction on the first track system and/or second track system. Once at the storage column, the lifting mechanism is then operated to grab the storage container and lift it into a container receiving space of the robotic load handling device where it is subsequently transported to a another location on the first track system and/or second track system commonly known as a drop-off port. The container is lowered to a suitable inventory handling station assembly to allow retrieval of the item from the storage container.
Like the first track system 514, the second track system 614 comprises a drop-off and/or pick-up port where the bots can drop off and/or pick up storage containers so that they can be transported to the inventory handling station assembly where the content of the storage containers can be accessed from outside of the grid framework structure. The columns extending below the drop-off and/or pick-up ports to the inventory handling device are termed the drop-off port column and the pick-up port column respectively. In addition to the upper port column and the lower port column for transferring storage containers between the first track system and the different levels of the inventory handling station assembly, the grid framework structure further comprises a second upper level port column extending between the second track system and the first access station at the first level, and a second lower level port column extending between the second track system and the second access station at the second level of the inventory handling station assembly. Like the upper level port column for transferring storage containers between the first track system 514 and the drop-off/pick-up areas at the first level, and the lower level port column for transferring storage containers between the first track system 514 and the drop-off/pick-up areas at the second level, the second upper level port column is configured for transferring storage containers between the second track system 614 and the drop-off/pick-up areas of the first access station at the first level, and the second lower level port column is configured for transferring storage containers between the second track system 614 and the drop-off/pick-up areas of the first access station at the second level. Again, the second upper and lower port columns can each be a single port column for dropping off and picking up storage containers to the respective drop-off and pick-up areas at the different first and second levels on the inventory handling station assembly. In other words, a single second upper level port column may be provided, through which storage containers are dropped off and picked up at the drop-off and pick-up areas of the first access station at the first level. Similarly, a single second lower level port column may be provided, through which storage containers are dropped off and picked up at the drop-off and pick-up areas of the second access station at the second level. In the particular embodiment shown in
The conveyor system 522b,c at the different levels of the inventory handling system assembly, namely the entry conveyor unit and the exit conveyor unit at the first and second level, extends into the grid framework structure sufficiently for the second upper level port column and the second lower level port column below the second track system 614 to drop-off and/or pick-up storage containers to their respective conveyor systems at the different levels. The entry conveyor unit and the exit conveyor unit at the first and second level of the inventory handling station assembly extend into the grid framework structure such that the entry conveyor unit at the first level extends into the first and second upper level port columns below the first track system 514 and the second track system 614. This enables one or more robotic load handling devices operative on the first track system 514 and the second track system 614 to drop off storage containers to the entry conveyor unit at the first and second levels for transport to their respective access stations of the inventory handling station assembly. Similarly, one or more robotic load handling devices operative on the first track system 514 and the second track system 614 are able to pick up storage containers on the exit conveyor unit at the first and second levels of the inventory handling station assembly.
For the first track system to port into the access stations at the different first and second levels, at least a portion of the first track system is shown in
For a robotic load handling device operational on the first track system 514 to port one or more storage container to the inventory handling station assembly below, in one example of the present invention shown in
The same principle applies when transferring storage containers from the pick-up area at the first level and the second level towards the first 514 and second 614 track system via respective pick-up port columns. In this way, the first and second track systems and their respective first and drop-off and pick-up port columns share a common inventory handling station assembly. The entry conveyor unit at the drop-off area 516b at the lower second level of the inventory handling station assembly is not only set back from the first level to receive storage containers from the first track system, the entry conveyor units at the drop-off areas 516a,b at the first level and second level are laterally displaced such that the upper level portal column extending from the first track system to the drop-off and/or pick-up areas do not obstruct movement of the bot (robotic load handling device) on the second track system. In this way, storage containers lowered onto either the entry conveyor units at the first ‘upper’ level and second ‘lower’ level can be conveyed to their respective access stations at the different levels where they are paused for one or more items to be picked from the storage containers, before being conveyed to their respective exit conveyor units. Similarly, the exit conveyor units at the pick-off areas 518a,b at the first level and second level are laterally displaced such that the upper level portal column extending from the first track system to the drop-off and/or pick-up areas do not obstruct movement of the bot (robotic load handling device) on the second track system. In the particular embodiment shown in
The direction of travel from the drop-off area to the pick-up area via the access station at each of the first and second level is shown to adopt a substantially ‘U’ shaped trajectory where the storage containers are conveyed into and out of the access station in a first and a third transport direction that are equal and opposite. The storage containers are conveyed in a second transport direction along the access station; the second transport direction being substantially perpendicular to the first and third transport direction such that the storage containers change direction twice when travelling from the drop-off area to the pick-up area via the access station. However, other trajectory shapes of the storage containers from the drop-off area to the pick-up area via the access station are applicable in the present invention, so as to enable storage containers to be transferred between the upper level first track system and the lower level second track system and the different first and second levels of the access station.
Whilst, the preferred embodiments of the present invention have been described in detail above, however, it should be understood that various modifications of the storage container encompassing different features described above are applicable within the scope of the present invention as defined in the claims. For example, the size of the grid cell openings of the second track system can be similar to arrangements of the grid cell openings of the track system described with reference to
| Number | Date | Country | Kind |
|---|---|---|---|
| 2107894.4 | Jun 2021 | GB | national |
| Filing Document | Filing Date | Country | Kind |
|---|---|---|---|
| PCT/EP2022/064660 | 5/30/2022 | WO |
