Patent Description:
Automated Storage and Retrieval Systems (ASRS), such as ASRS product lifts and automated shuttles configured to move along shuttle guide tracks, are used as material handling systems to facilitate movement of high volumes of articles and maximize the use of valuable storage space. ASRSs are key components in material handling environments by combining automation, software, and labor to optimize the productivity and throughput in a variety of operations. Furthermore, ASRSs provide flexibility and speed allowing use in applications ranging from e-commerce and omnichannel fulfillment to article distribution. Applicant has identified several technical challenges associated with utilizing automated shuttles in an ASRS to retrieve objects stored at discrete storage locations within a storage rack arrangement. Through applied effort, ingenuity, and innovation, many of these identified challenges have been overcome by developing solutions that are included in embodiments of the present invention, many examples of which are described in detail herein.

<CIT> discloses an automated warehouse storage system including a multilevel storage array with storage distributed along multiple aisles. Each aisle of which has a set of storage levels and each level has storage locations distributed along the aisle. There is a guideway network extending through the multilevel storage array and is configured for autonomous vehicles to move along the guideway network within the multilevel storage array. The guideway network includes an inter-aisle guideway spanning at least two of the multiple aisles and a set of guideway levels extending in an aisle of the multiple aisles and disposed so that each guideway level is at a different one of the storage levels and the vehicles on the guideway level can access the storage locations distributed along the aisle.

<CIT> discloses an order fulfillment system including a multi-level tote storage structure, one or more autonomous mobile robots configured to pick, transport and place one or more tote; one or more workstations configured to accommodate a picker that transports one or more caches from a tote on one of the autonomous mobile robots to a "put" location. The autonomous mobile robots are configured to move from level to level in the order fulfillment apparatus.

<CIT> discloses a track arrangement for self-driven carriages in a storage rack arrangement for automatically storing and accessing objects. The storage rack arrangement comprises a plurality of storage sites being arranged in at least one rack extending over k storage levels. The track arrangement connects each storage level with at least one Interaction site for automatically processing stored objects and/or automatically issuing objects to be stored.

Various embodiments are directed to an automated storage and retrieval system and methods of using the same. Various embodiments are directed to an automated storage and retrieval system according to claim <NUM> comprising: a plurality of storage aisles, each storage aisle comprising a plurality of storage locations positioned adjacent to an aisle track that extends along an aisle length; a plurality of shuttles configured to travel throughout the automated storage and retrieval system to execute a materials handling operation; at least one vertical lift; a plurality of inter-aisle shuttle outlet tracks configured to facilitate shuttle traffic flow in at least substantially the same direction, the plurality of inter-aisle shuttle outlet tracks comprising: a first inter-aisle shuttle outlet track configured to facilitate shuttle traffic flow to the at least one vertical lifts via at least one lift interface position defined along the first inter-aisle shuttle outlet track; and a second inter-aisle shuttle outlet track arranged in an at least substantially parallel configuration relative to the first inter-aisle shuttle outlet track; wherein the plurality of inter-aisle shuttle outlet tracks is configured to enable a transfer of at least one of the plurality of shuttles between the first inter-aisle shuttle outlet track and the second inter-aisle shuttle outlet track at one or more transfer locations along the first inter-aisle shuttle outlet track; wherein the aisle track of each storage aisle of the plurality of storage aisles is configured to facilitate shuttle traffic flow along the aisle length thereof in a first shuttle travel direction such that each of the plurality of storage aisles is defined in part by a unidirectional shuttle traffic flow pattern.

In various embodiments, the automated storage and retrieval system may further comprise a central controller configured to transmit instructional signals to each of the plurality of shuttles to cause the plurality of shuttles to travel throughout the automated storage and retrieval system. In various embodiments, the plurality of storage aisles may be defined by further comprising a rack arrangement comprising a plurality of storage racks, each storage rack being defined by a plurality of storage shelves arranged in a vertically stacked configuration such that the rack arrangement comprises a plurality of rack arrangement levels, wherein each of the plurality of storage aisles is provided within a first rack arrangement level. In certain embodiments, the plurality of storage racks may be arranged in an at least substantially parallel configuration such that each of the plurality of storage aisles is parallel to one another.

According to the invention, the automated storage and retrieval system further comprises an inter-aisle shuttle inlet track operatively connected to a respective aisle inlet end of each of the plurality of storage aisles. In certain embodiments, the inter-aisle shuttle inlet track is operatively connected to the respective aisle inlet end of each of the plurality of storage aisles such that each of the plurality of storage aisle is accessible to the plurality of shuttles via the inter-aisle shuttle inlet track. The inter-aisle shuttle inlet track is configured to facilitate unidirectional shuttle traffic flow along a shuttle inlet track length thereof. The automated storage and retrieval system further comprises a shuttle transport track extending from the plurality of inter-aisle shuttle outlet tracks to the inter-aisle shuttle inlet track. In certain embodiments, the shuttle transport track is configured to facilitate transportation of the plurality of shuttles from the plurality of inter-aisle shuttle outlet tracks to the inter-aisle shuttle inlet track. Further, in certain embodiments, the automated storage and retrieval system may be configured to enable a shuttle recirculation traffic flow pattern defined at least in part by respective unidirectional shuttle traffic flow patterns along each of the shuttle transport track, the inter-aisle shuttle inlet track, the plurality of inter-aisle shuttle outlet tracks, and at least one of the plurality of storage aisles.

In various embodiments, the automated storage and retrieval system may further comprise a shuttle storage position that is defined by a shuttle guide track segment along which the automated storage and retrieval system is configured to store one or more of the plurality of shuttles that are configured in a standby configuration at a particular instance. In certain embodiments, the shuttle storage position may be defined along a secondary shuttle transport track extending at least partially between the plurality of inter-aisle shuttle outlet tracks and an inter-aisle shuttle inlet track operatively connected to each of the plurality of storage aisles. In various embodiments, the first inter-aisle shuttle outlet track may be defined at least in part by a first track length and the second inter-aisle shuttle outlet track is defined at least in part by a second track length that is at least substantially equal to the first track length.

Various embodiments are directed to a method according to claim <NUM> of operating an automated storage and retrieval system using a unidirectional shuttle traffic flow pattern, the method comprising: providing an automated storage and retrieval system comprising a first storage aisle, the first storage aisle comprising an aisle track extending along an aisle length and a plurality of storage locations positioned at least substantially adjacent the aisle track, wherein the aisle track is configured to facilitate movement of a plurality of shuttles along the first storge aisle in a shuttle travel direction defined along the aisle length; causing a first shuttle to travel to a first storage location provided within the first storage aisle such that the first shuttle moves along an aisle track of the first storage aisle in a first shuttle travel direction; causing a second shuttle to travel to a second storage location provided within the first storage aisle such that the second shuttle moves along the aisle track of the first storage aisle in the first shuttle travel direction and such that both the first shuttle and the second shuttle are positioned within the first storage aisle at a first instance; and causing the first shuttle to travel in the first shuttle travel direction from the first storage location to a first storage aisle outlet of the first storage aisle.

In various embodiments, the method may further comprise causing the second shuttle to travel along the aisle track in the first shuttle travel direction to the first storage aisle outlet. In various embodiments, the method may further comprise accessing, via the first shuttle, a first vertical lift of a plurality of vertical lifts by causing the first shuttle to travel from the first storage aisle to a first lift interface position defined along a first inter-aisle shuttle outlet track. Further, according to the invention, the method comprises determining that the first shuttle is stopped along the first inter-aisle outlet track at a first lift interface position; identifying that the second shuttle traveling along the first inter-aisle outlet track is in an upstream position relative to the first shuttle; and causing the second shuttle to transfer from the first inter-aisle outlet track to a second inter-aisle outlet track arranged in an at least substantially parallel configuration relative to the first inter-aisle shuttle outlet track.

In various embodiments, the method may further comprise determining a system bandwidth of the automated storage and retrieval system based at least in part on a number of shuttles of the plurality of shuttles determined to be executing a materials handling operation at a measurement instance; identifying a third shuttle of the plurality of shuttles this is configured in a standby configuration; providing instructions to the third shuttle to execute a third materials handling operation, so as to increase the number of shuttles of the plurality of shuttles in operation within the automated storage and retrieval system. In various embodiments, the method may further comprise upon determining that that the first shuttle has executed a first materials handling operation, providing instructions to the first shuttle to execute a second materials handling operation, including causing the first shuttle to travel to a third storage location provided within the first storage aisle such that the first shuttle moves along the aisle track of the first storage aisle in the first shuttle travel direction. Further, in certain embodiments, the automated storage and retrieval system comprises a plurality of storage aisles, and wherein the method may further comprise identifying that first storage aisle outlet of the first storage aisle is arranged in an upstream position from a first lift interface portion corresponding to a first vertical lift relative to a unidirectional shuttle recirculation traffic flow pattern defined by the automated storage and retrieval system; and wherein causing the first shuttle to travel to the first storage location provided within the first storage aisle comprises selectively causing the first shuttle to travel to the first storage aisle of the plurality of storage aisles based at least in part on the upstream position of the first storage aisle outlet relative to the first lift interface portion corresponding to the first vertical lift.

The present disclosure more fully describes various embodiments with reference to the accompanying drawings. It should be understood that some, but not all embodiments are shown and described herein. Indeed, the embodiments may take many different forms, and accordingly this disclosure should not be construed as limited to the embodiments set forth herein. Rather, these embodiments are provided so that this disclosure will satisfy applicable legal requirements.

It should be understood at the outset that although illustrative implementations of one or more aspects are illustrated below, the disclosed assemblies, systems, and methods may be implemented using any number of techniques. The disclosure should in no way be limited to the illustrative implementations, drawings, and techniques illustrated below, but may be modified within the scope of the appended claims. While values for dimensions of various elements are disclosed, the drawings may not be to scale.

The words "example," or "exemplary," when used herein, are intended to mean "serving as an example, instance, or illustration. " Any implementation described herein as an "example" or "exemplary embodiment" is not necessarily preferred or advantageous over other implementations.

The words "lateral," longitudinal," and "vertical," when used herein, are intended to be used for referential and/or illustrative purposes in order to provide context for one or more aspects of the present invention, and should be strictly interpreted as being limited a particular universal direction. By way of non-limiting example, as described herein with reference to the directional references provided in the figures, the "lateral" direction may extend along an x-axis, a "longitudinal" direction may extend perpendicularly within at least substantially the same plane as a lateral direction, such as, for example, along a y-axis, and a "vertical" direction may extend perpendicularly within an at least substantially perpendicular plane relative to both the lateral and longitudinal directions, such as, for example, along an a z-axis.

The components illustrated in the figures represent components that may or may not be present in various embodiments of the invention described herein such that embodiments may include fewer or more components than those shown in the figures while not departing from the scope of the invention.

Automated storage and retrieval systems may utilize various material handling products such as various carriages, carts, lifts, conveyors, and/or the like to facilitate the transportation of objects to a desired delivery location within a factory or a warehouse. For example, automated shuttles may be used to transport objects to and/or from various storage locations organized along storage aisles arranged within a storage environment. Further, a vertical lift assembly may be used to facilitate the vertical transportation of one or more objects between different levels of a storage rack or other storage environment. Various automated storage and retrieval systems may include a shuttle provided within each storage aisle of the system that is configured execute a retrieval operation by moving in a first direction along the storage aisle to a storge location, retrieving an object disposed within the storage location, and returning to a vertical lift provided adjacent the storage aisle by moving in a second direction opposite the first direction along the storage aisle to the vertical lift. For example, such automated storage and retrieval systems may provide a vertical lift adjacent each storage aisle defined therein such that the shuttle configured for bidirectional travel within that particular storage aisle can access a respective vertical lift adjacent thereto in order to facilitate the transportation of an object between the storage aisle and a remote location within a materials handling environment.

The present invention relates to an automated storage and retrieval system comprising a plurality of storage aisles, each comprising an aisle track configured to facilitate shuttle traffic flow of a plurality of shuttles along the aisle length thereof in a first shuttle travel direction such that each of the plurality of storage aisles is defined in part by a unidirectional shuttle traffic flow pattern. As described herein, the exemplary AS/RS is configured such that the plurality of shuttles are transported throughout the AS/RS according to a shuttle recirculation traffic flow pattern defined at least in part by the unidirectional shuttle traffic flow pattern of each of the plurality of parallel storage aisles. The present invention is preferrable to automated storage and retrieval systems comprising shuttles that are limited to bidirectional travel along respective storage aisles, as the unidirectional shuttle traffic flow pattern in each of the storage aisles of the AS/RS at least substantially eliminates the risk of gridlock and/or traffic backup caused by two shuttles simultaneously positioned within the same storage aisle that are moving in opposing directions and/or along conflicting shuttle traffic paths. As such, the present invention allows for the AS/RS to be operated such that a plurality of shuttles executing respective materials handling operations may be positioned within the same storage aisle at the same time, thereby increasing system output by minimizing the inefficiencies associated with the travel time of bidirectional shuttles to and from various storage locations within a single storage aisle.

Further, the present invention includes an AS/RS comprising a plurality inter-aisle shuttle outlet tracks configured to facilitate shuttle traffic flow in at least substantially the same direction, including a first inter-aisle shuttle outlet track configured to facilitate shuttle traffic flow to each of a plurality of vertical lifts via corresponding lift interface positions defined along the first inter-aisle shuttle outlet track, and a second inter-aisle shuttle outlet track arranged in an at least substantially parallel configuration relative to the first inter-aisle shuttle outlet track. As described herein, the plurality of inter-aisle shuttle outlet tracks is configured to enable a transfer of at least one of the plurality of shuttles between the first inter-aisle shuttle outlet track and the second inter-aisle shuttle outlet track at one or more transfer locations along the first inter-aisle shuttle outlet track. In such an exemplary configuration, the plurality of inter-aisle shuttle outlet tracks of the AS/RS may embody parallel passing lanes that provide access for each of the plurality of shuttles within a particular level of the AS/RS to access each of the plurality of vertical lifts for executing various storage and/or retrieval operations, thereby maximizing the efficiency and collective output of the plurality of vertical lifts. Further, the plurality of inter-aisle shuttle outlet tracks of the present invention, as described herein, may facilitate an at least substantially continuous flow of shuttle traffic throughout the AS/RS by providing the second inter-aisle shuttle outlet track that may be selectively used as a passing lane to which at least a portion of the shuttles may be transferred (e.g., from the first inter-aisle shuttle outlet track) to avoid a shuttle stopped at a lift interface position along the first inter-aisle shuttle outlet track, thereby at least substantially maximizing system throughput by minimizing bottlenecks that my result from traffic interferences within the AS/RS.

In various embodiments, a material handling system may include an exemplary automated storage and retrieval system (AS/RS) comprising a rack arrangement comprising a plurality of storage racks. For example, a storage rack of the AS/RS may be defined as a series of vertically arranged shelves, each supported by a support frame (e.g., a post and beam rack). The support frame may comprise vertical support members separating various levels within the storage rack, and horizontal support members supporting individual shelves. Each shelf may define and/or comprise a plurality of storage locations (e.g., separated into one or more bays) configured for storing at least one object (e.g., a storage container, a product, a spool, and/or other object configurations) therein. In various embodiments, wherein the rack arrangement of the AS/RS comprises a plurality of storage racks, the rack arrangement may be defined at least in part by a plurality of rack arrangement levels, each corresponding to a respective level of the rack arrangement defined within a corresponding at least substantially horizontal plane. For example, in an exemplary circumstance wherein a rack arrangement of an exemplary AS/RS comprises a plurality of storage racks, each comprising a plurality of storage shelves arranged in a vertically stacked configuration such that each storage rack is defined by a plurality of storage rack levels, a rack arrangement level may be defined collectively by each of the storage rack levels from the storage racks of the rack arrangement that are defined within a common (e.g., at least substantially the same) horizontal plane (e.g., level). Further, a rack arrangement level defined within an at least substantially horizontal plane may be defined by each storage shelf (e.g., each of the storage locations provided therein) of the plurality of storage racks that is provided within the least substantially horizontal plane.

In various embodiments, the plurality of racks of a rack arrangement of the AS/RS may be arranged such that two adjacent storage racks are provided in an at least substantially parallel configuration relative to one another. As described in further detail herein, two adjacent storage racks may be arranged such that an aisle is provided therebetween. For example, the aisle may be defined at least in part by the perpendicular separation distance between adjacent storage racks.

Further, as described herein, an exemplary AS/RS may comprise a plurality of shuttle guide tracks extending along and/or between each of the plurality of storage racks of the rack arrangement. The plurality of shuttle guide tracks may be configured such that a plurality of automated shuttles configured for travel thereon may move along the tracks between various racks (e.g., storage locations) within the rack arrangement. In various embodiments, the plurality of shuttle guide tracks of the AS/RS may comprise a plurality of aisle tracks, each provided along a respective aisle length between a respective pair of two adjacent storage racks. As described in further detail herein, an exemplary AS/RS may comprise a plurality of storage aisles, each comprising a first storage shelf and a second storage shelf, defined by respective portions of adjacent first and second storage racks that are provided in the same rack arrangement level (e.g., within at least substantially the same horizontal plane), and an aisle track extending between the first storage shelf and the second storage shelf along an aisle length such that each of the storage locations within the first and second storage shelves are accessible to a shuttle via the aisle track provided therebetween.

In various embodiments, a shuttle of the AS/RS may be configured for movement along each of the plurality of shuttle guide tracks provided within a rack arrangement level of the system (e.g., within a singular horizontal plane). For example, the plurality of shuttle guide tracks may comprise a first plurality of shuttle guide tracks provided within a first rack arrangement level and configured to enable shuttle transportation of a first plurality of shuttles to and/or from a first storage aisle defined by a first storage shelf, a second storage shelf, and a first aisle track provided within the first rack arrangement level. In such an exemplary circumstance, the plurality of shuttle guide tracks of the same AS/RS may further comprise a second plurality of shuttle guide tracks provided within a second rack arrangement level and configured to enable shuttle transportation of a second plurality of shuttles to and/or from a second storage aisle defined by a third storage shelf, a fourth storage shelf, and a second aisle track provided within the second rack arrangement level. Further, in various embodiments, as described in further detail herein, a rack arrangement of an exemplary AS/RS may comprise a plurality of storage racks arranged such that each rack arrangement level of the AS/RS comprises a plurality of storage aisles, each of which may be accessible to a shuttle configured to travel along the plurality of shuttle guide tracks within the rack arrangement level.

<FIG> illustrates a schematic view of an exemplary automated storage and retrieval system according to various embodiments described herein. In particular, <FIG> illustrates a schematic view of an exemplary rack arrangement level <NUM> of an AS/RS <NUM>, the rack arrangement level <NUM> comprising a storage aisle <NUM>. As shown, a storage aisle <NUM> may be defined by various components of an exemplary rack arrangement that are provided within at least substantially the same horizontal plane, including, for example, a first storage shelf <NUM> and a second storage shelf <NUM> of adjacent first and second storage racks, respectively. As illustrated, the first and second storage shelves <NUM>, <NUM> of an exemplary storage aisle <NUM> may each extend in an at least substantially longitudinal direction, such as, for example, in the y-direction, as illustrated, and may be arranged in an at least substantially parallel configuration relative to one another. An exemplary storage aisle <NUM> further includes an aisle track <NUM> extending between the first and second storage shelves <NUM>, <NUM> in at least substantially the same longitudinal direction as the first and second storage shelves <NUM>, <NUM> provided on either side thereof. For example, the aisle track <NUM> of a storage aisle <NUM> may be arranged in an at least substantially parallel configuration relative to one or both of the first and second storage shelves <NUM>, <NUM> adjacent thereto. As shown, an aisle track <NUM> may be defined at least in part by an aisle length that extends between the first aisle end <NUM> and the second aisle end <NUM> thereof.

The AS/RS <NUM> comprises a plurality of automated shuttles <NUM> configured to travel along the plurality of shuttle guide tracks provided within a rack arrangement level to facilitate the retrieval, storage, and/or transportation of various objects throughout the AS/RS <NUM>. In various embodiments, a plurality of shuttles <NUM> may be disposed along each rack arrangement level of the rack arrangement. As such, the shuttle(s) <NUM> may be configured to move along the plurality of shuttle guide tracks provided within a rack arrangement level <NUM> in order to selectively remove and/or place objects into a storage location within a storage shelf (e.g., first storage shelf <NUM>, second storage shelf <NUM>) provided within the rack arrangement level <NUM>. As illustrated, an exemplary aisle track <NUM> is configured to enable shuttle traffic along the aisle length thereof in order to facilitate movement of one or more of the plurality of automated shuttles <NUM> to and/or from one or more storage locations within the storage aisle <NUM>. In such an exemplary configuration, a shuttle <NUM> may travel along aisle track <NUM> in order to retrieve and/or dispose an object into one of the plurality of storage locations provided within either the first storage shelf <NUM> (e.g., first storage location 101a, second storage location 101b, third storage location 101n, and/or the like) or the second storage shelf <NUM>.

In various embodiments, the shuttle <NUM> may be any type of one-level shuttle (OLS) vehicle typically used in a AS/RS, such as a shuttle, a carrier, a bot, and/or the like. In various embodiment, the shuttle <NUM> may be a self-contained unit, receiving power (e.g., <NUM> VDC) from a bus bar located inside a shuttle guide track that may be mounted to the storage rack. In various embodiments, the power guide track (e.g., <NUM> VDC power supplied to the track) may be powered from a DC power panel. In various embodiments, a single DC power panel can power a plurality of shuttles (e.g., up to six shuttles). In various embodiments, the shuttle <NUM> may receive control system commands over a Wireless Local Area Network (WLAN). In various embodiments, a shuttle <NUM> may have one or more wheels to facilitate movement thereof along a shuttle guide track via a motor. In various embodiments, the shuttle guide track may be affixed to the storage rack. However, it should be understood that any of a variety of movement mechanisms may be utilized for moving the shuttle <NUM> (e.g., belt-drive systems, magnetic movement mechanisms, chain-drive systems, and/or the like). Moreover, it should be understood that the movement mechanisms may be defined within the shuttle <NUM> (e.g., a motor positioned on the shuttle) or within the storage rack (e.g., motors within the storage rack). In various embodiments, an exemplary shuttle <NUM> may comprise one or more sensors configured movement of the shuttle <NUM> to an intended storage location and/or engagement of the shuttle <NUM> with a particular object in a given storage location. For example, the shuttle <NUM> may be equipped with a proximity sensor to determine the longitudinal and/or lateral position of the shuttle <NUM> within a given rack arrangement level (e.g., by identifying the storage aisle in which the shuttle <NUM> is positioned, identifying one or more storage locations disposed at least substantially adjacent the shuttle <NUM>, and/or the like, or any combination thereof), and/or the position of the shuttle <NUM> relative to one or more other shuttles of the plurality provided within the same rack arrangement level <NUM>. In various embodiments, the shuttle <NUM> may also be equipped with sensors and onboard devices, such as Wi-Fi antenna for communication with a Warehouse Control System (WCS) and/or Warehouse Execution System (WES), overload protection, one or more power supplies (e.g., <NUM> Volt power supply and/or <NUM> volt power supply), digital input and output modules, and/or the like.

Further, an exemplary AS/RS <NUM> may comprise a plurality of vertical lifts <NUM> configured to facilitate the vertical transportation of objects between the multiple levels of the AS/RS <NUM>. At least a portion of the plurality of lifts <NUM> of the AS/RS <NUM> may be configured to receive an object retrieved by a shuttle <NUM> from a storage aisle <NUM> provided within a rack arrangement level <NUM> (e.g., from an exemplary storage location 101a within a first storage shelf <NUM> of the storage aisle <NUM>) and vertically move (e.g., lower) the retrieved object to a lift drop-off station <NUM>. The lift drop-off station <NUM> may be connected to an out-feed conveyor <NUM> that is configured to deliver the object retrieved by the shuttle <NUM> from within the rack arrangement level <NUM> to a downstream location, such as, for example, a destination location within a manufacturing environment. Alternatively, and/or additionally, at least a portion of the plurality of lifts <NUM> of the AS/RS <NUM> may be configured to receive an object to be stored at a storage location within the first rack arrangement level <NUM> of the AS/RS <NUM> at the lift drop-off station <NUM>, wherein the object to be stored may be delivered to the lift drop-off station <NUM> via an in-feed conveyor <NUM> configured to deliver the object to be stored from an upstream location to the lift drop-off station <NUM>. At least a portion of the plurality of lifts <NUM> may be configured to vertically move (e.g., raise) the object to be stored from the lift drop-off station <NUM> to a first rack arrangement level <NUM>, wherein it may be transferred to one of the plurality of shuttles <NUM> provided along the plurality of tracks within the rack arrangement level <NUM> and delivered to a storage location within an exemplary storage aisle <NUM>. As described in further detail herein, at least a portion of the plurality of lifts provided within the AS/RS <NUM> may be positioned in an at least substantially aligned configuration, such as, for example, along a second aisle end (e.g., an aisle outlet end) such that the plurality of shuttles provided in the AS/RS <NUM> may access the at least a portion of the plurality of lifts <NUM> upon exiting a storage aisle (e.g., storage aisle <NUM>). Additionally, in various embodiments, one or more of the plurality of lifts may be positioned along an aisle length of one or more storage aisles (e.g., adjacent one or more of the storage shelves aligned along the corresponding aisle track), so as to embody an intra-aisle lift that may be accessed by a shuttle travelling in a shuttle travel direction along the corresponding aisle track.

An exemplary AS/RS <NUM> is operated such that each shuttle <NUM> that is moved throughout a storage aisle <NUM> travels in the same singular direction (e.g., a shuttle travel direction) along the aisle track <NUM> from the first aisle end <NUM> to the second aisle end <NUM>. As such, each storage aisle <NUM> of an exemplary AS/RS <NUM> is defined in part by a unidirectional shuttle traffic flow pattern that is defined along the aisle track <NUM> thereof. For example, in various embodiments, the plurality of shuttle guide tracks within a particular rack arrangement level of an AS/RS <NUM> may be configured such that a shuttle <NUM> executing a retrieval operation relating to an object disposed within a storage location 101a provided within the storage aisle <NUM> may be received by the aisle track <NUM> of the storage aisle <NUM> at a first aisle end <NUM> thereof. The storage aisle <NUM> is configured to facilitate a unidirectional shuttle traffic flow along the aisle length of the aisle track <NUM>, such that each shuttle <NUM> traveling along the aisle track <NUM> moves in a shuttle travel direction, such as, for example, in a first longitudinal direction <NUM> (e.g., in the negative y-direction as illustrated). For example, the shuttle <NUM> may stop at a position along the aisle track <NUM> that is adjacent to the designated storage location 101a defined within the first storage shelf <NUM> of the storage aisle <NUM> in order to access to object disposed therein. In such an exemplary configuration, upon retrieving the object from the storage location 101a, the shuttle <NUM> may continue travelling in the shuttle travel direction (e.g., the first longitudinal direction <NUM>) towards the second aisle end <NUM> of the aisle track <NUM>. As described herein, in an exemplary circumstance wherein an AS/RS <NUM> is operated such that each storage aisle <NUM> provided therein defines a unidirectional shuttle traffic flow pattern from a first aisle end <NUM> to a second aisle end <NUM>, a plurality of shuttles <NUM> may at least substantially simultaneously travel to a respective plurality of storage locations (e.g., storage locations 101a, 101b, 101n) with the same storage aisle <NUM> such that the plurality of shuttles <NUM> are each positioned along the aisle track <NUM> at substantially the same time. By operating the AS/SR <NUM> that each of the shuttles <NUM> travel along the aisle track <NUM> of a storage aisle <NUM> in the same shuttle travel direction (e.g., the first longitudinal direction <NUM>) the risk of shuttle collision and/or shuttle traffic flow bottlenecks caused by two or more shuttles <NUM> being moved along intersecting, overlapping, and/or otherwise incompatible shuttle travel paths along the same aisle track <NUM> may be at least substantially mitigated.

Such a unidirectional shuttle traffic flow pattern of each storage aisle <NUM> within a rack arrangement level <NUM> is enabled by a looped track configuration of the plurality of shuttle guide tracks provided within the rack arrangement level <NUM>. For example, the plurality of shuttle guide tracks provided within a rack arrangement level <NUM> may be arranged so as to define an looped track circuit comprising an at least partially closed looped configuration, wherein an exemplary shuttle <NUM>, upon having travelled along the aisle length of the aisle track <NUM> in the first longitudinal direction <NUM> to the second aisle end <NUM>, may exit the storage aisle <NUM> and travel along at least a portion of the looped track circuit to be recirculated to the first aisle end <NUM> of the aisle track <NUM>. In various embodiments, an exemplary AS/RS <NUM> comprising a storage aisle <NUM> provided within a rack arrangement level <NUM> and configured to facilitate shuttle transportation along an aisle track <NUM> thereof according to a unidirectional shuttle traffic flow pattern defined at least in part by the first longitudinal direction <NUM> may further include a plurality of shuttle guide tracks provided within the rack arrangement level <NUM> that collectively facilitate a shuttle recirculation traffic flow pattern. As illustrated in <FIG>, such an exemplary rack arrangement level <NUM> of an AS/RS <NUM> includes a plurality of shuttle guide tracks comprising the aisle track <NUM> of the storage aisle <NUM>, a shuttle transport track <NUM>, an inter-aisle shuttle inlet track <NUM>, and a plurality of inter-aisle shuttle outlet tracks <NUM>.

The aisle track <NUM> of a storage aisle <NUM>, the shuttle transport track <NUM>, the inter-aisle shuttle inlet track <NUM>, and the plurality of inter-aisle shuttle outlet tracks <NUM> provided within the rack arrangement level <NUM> collectively define a looped track circuit configured such that the plurality of shuttles <NUM> provided within the rack arrangement level <NUM> may travel along the aforementioned shuttle guide tracks so as to define a shuttle recirculation traffic flow pattern defined at least part by a plurality of shuttles <NUM> serially travelling along the aisle track <NUM> in the first longitudinal direction <NUM> (e.g., from the first aisle end <NUM> to the second aisle end <NUM>). For example, the shuttle recirculation traffic flow pattern exhibited by the illustrated plurality of shuttles <NUM> travelling throughout the rack arrangement level <NUM> may be defined at least in part by two or more shuttles <NUM> of the plurality being at least substantially simultaneously positioned within the storage aisle <NUM> (e.g., travelling along the aisle track <NUM> in the first longitudinal direction <NUM>) at respective positions along the aisle length thereof. In various embodiments, each of the plurality of shuttle guide tracks that define at least a portion of the looped track circuit provided within a rack arrangement level <NUM> may be configured to define a unidirectional shuttle traffic flow pattern along the track length thereof. For example, each of the shuttle transport track <NUM>, the inter-aisle shuttle inlet track <NUM>, and the plurality of inter-aisle shuttle outlet tracks <NUM> are configured for unidirectional shuttle traffic along their respective track lengths such that a shuttle travelling thereon moves in a respective singular direction along the length of the shuttle guide track. Accordingly, in various embodiments wherein the shuttle transport track <NUM>, the inter-aisle shuttle inlet track <NUM>, the plurality of inter-aisle shuttle outlet tracks <NUM>, and the aisle track <NUM> are arranged in an at least substantially continuous looped track circuit that connects the second aisle end <NUM> of the aisle track <NUM> to the first aisle end <NUM>, as illustrated in <FIG>, the plurality of shuttle guide tracks within the rack arrangement level <NUM> are configured to facilitate an at least generally clockwise-or, alternatively, counterclockwise-shuttle recirculation traffic flow pattern through the looped track circuit, as described herein.

A plurality of inter-aisle shuttle outlet tracks <NUM> collectively defines a segment of shuttle guide tracks extending between a second aisle end <NUM> of a storage aisle <NUM> and a shuttle transportation track <NUM>. Further, the plurality of inter-aisle shuttle outlet tracks <NUM> is arranged so as to facilitate transportation of a shuttle <NUM> from a storage aisle <NUM> and to each of a plurality of vertical lifts <NUM> provided within an AS/RS <NUM>. For example, the plurality of inter-aisle shuttle outlet tracks <NUM> may be arranged so as to extend in a direction that at least substantially intersects a second aisle end <NUM> of each of the storage aisles <NUM> provided within a rack arrangement level <NUM> (e.g., in an at least substantially a perpendicular direction relative to the aisle length). Accordingly, in various embodiments, the plurality of inter-aisle shuttle outlet tracks <NUM> may be at least substantially immediately downstream from each of the storage aisles <NUM> within the rack arrangement level <NUM> such that a shuttle <NUM> travelling along the aisle track <NUM> according to the unidirectional shuttle traffic flow pattern, as described herein, may exit the storage aisle <NUM> via a respective second aisle end <NUM> and be received by the plurality of inter-aisle shuttle outlet tracks <NUM>. Further, the plurality of inter-aisle shuttle outlet tracks <NUM> may be arranged to extend at least substantially between each of the plurality of lifts <NUM> of the AS/RS <NUM> such that each of the plurality of lifts <NUM> is accessible to a shuttle <NUM> via the plurality of inter-aisle shuttle outlet tracks <NUM>. Each of the plurality of lifts <NUM> is accessible to a shuttle <NUM> via a corresponding lift interface position defined along the plurality of inter-aisle shuttle outlet tracks <NUM>, such that a shuttle <NUM> travelling in the first lateral direction <NUM> along the plurality of inter-aisle shuttle outlet tracks <NUM> may be stopped at a lift interface position thereon in order to dispense and/or retrieve an object from a corresponding lift <NUM> adjacent thereto.

As illustrated in <FIG>, an exemplary AS/RS <NUM> may comprise a plurality of lifts <NUM> arranged in an at least substantially aligned configuration in one or more directions, such as, for example, in a substantially lateral distribution (e.g., distributed along the x-axis, as illustrated). As such, the plurality of inter-aisle shuttle outlet tracks <NUM> may be arranged in an at least substantially perpendicular configuration relative to the aisle track <NUM> such that a shuttle <NUM> traveling along one of the plurality of inter-aisle shuttle outlet tracks <NUM> moves along the track length thereof in a first lateral direction <NUM> (e.g., in the negative x-direction as illustrated). The plurality of inter-aisle shuttle outlet tracks <NUM> comprises a first inter-aisle shuttle outlet track <NUM> and a second inter-aisle shuttle outlet track <NUM> arranged in an at least substantially parallel configuration relative to one another. Each of the first inter-aisle shuttle outlet track <NUM> and the second inter-aisle shuttle outlet track <NUM> may be configured to define a unidirectional shuttle traffic flow pattern along a respective track length thereof. For example, both the first inter-aisle shuttle outlet track <NUM> and the second inter-aisle shuttle outlet track <NUM> may be configured such that exemplary shuttles <NUM> travelling along the respective inter-aisle shuttle outlet tracks <NUM>, <NUM> may move in a first lateral direction <NUM>.

As illustrated, the first inter-aisle shuttle outlet track <NUM> of the plurality <NUM> may extend at least substantially between the plurality of lifts <NUM> of the AS/RS <NUM> such that each of the plurality of lifts <NUM> may be accessed by a shuttle <NUM> travelling along the first inter-aisle shuttle outlet track <NUM> via a corresponding plurality of lift interface positions defined along the first inter-aisle shuttle outlet track <NUM>. As described herein, a shuttle <NUM> travelling in the first lateral direction <NUM> along the first inter-aisle shuttle outlet track <NUM> may stop along the first inter-aisle shuttle outlet track <NUM> at a lift interface position adjacent a corresponding lift (e.g., adjacent a first vertical lift 200a or a second vertical lift 200b of the plurality <NUM>) in order to dispense and/or retrieve an object from the corresponding lift of the plurality <NUM>. As further illustrated in <FIG>, the second inter-aisle shuttle outlet track <NUM> of the plurality of inter-aisle shuttle outlet tracks <NUM> is arranged at least substantially adjacent the first inter-aisle shuttle outlet track <NUM> and configured to extend at least substantially parallel direction relative to the first inter-aisle shuttle outlet track <NUM>. A plurality of inter-aisle shuttle outlet tracks <NUM> defined by such an exemplary configuration may enable parallel shuttle traffic flow patterns in the first and second inter-aisle shuttle outlet tracks <NUM>, <NUM> that are defined by respective unidirectional traffic flows in the first lateral direction <NUM> along each of the parallel track lengths. The plurality of inter-aisle shuttle outlet tracks <NUM> are configured such that a shuttle <NUM> travelling in the first lateral direction <NUM> along either the first inter-aisle shuttle outlet track <NUM> or the second inter-aisle shuttle outlet track <NUM> may be selectively transferred to the adjacent, parallel inter-aisle shuttle outlet track of the plurality <NUM>. For example, in various embodiments, wherein a first shuttle <NUM> is traveling in the first lateral direction <NUM> along the first inter-aisle shuttle outlet track <NUM> and a second shuttle <NUM> is stopped along the first inter-aisle shuttle outlet track <NUM> in a downstream position relative to the first shuttle <NUM> at a lift interface position corresponding to a second vertical lift 200b, the plurality of inter-aisle shuttle outlet tracks <NUM> may be configured such that the first shuttle <NUM> may be transferred to the second inter-aisle shuttle outlet track <NUM>. Upon being moving from the first inter-aisle shuttle outlet track <NUM> to the second inter-aisle shuttle outlet track <NUM>, the first shuttle <NUM> may continue to travel in the first lateral direction <NUM> (e.g., along the second inter-aisle shuttle outlet track <NUM>) according to the shuttle recirculation traffic flow pattern, thereby avoiding a traffic stoppage along the first inter-aisle shuttle outlet track <NUM> that may result from the at least temporarily stationary second shuttle <NUM> being engaged with the second lift 200b.

In such an exemplary configuration, wherein the plurality of inter-aisle shuttle outlet tracks <NUM> are arranged in an at least substantially parallel configuration and configured for unidirectional shuttle traffic thereon in the same direction (e.g., the first lateral direction <NUM>), the plurality of inter-aisle shuttle outlet tracks <NUM> may function as parallel passing lanes between which an exemplary shuttle <NUM> may be transferred in order to facilitate shuttle engagement with each of a plurality of lifts <NUM> of the AS/RS <NUM> via the lift interface positions defined along the first inter-aisle shuttle outlet track <NUM>, while simultaneously enabling an at least substantially continuous shuttle traffic flow of at least a portion of the plurality of shuttles <NUM> travelling from the storage aisle <NUM> (e.g., the second aisle end <NUM>) to the shuttle transport track <NUM>. The plurality of inter-aisle shuttle outlet tracks <NUM> is configured such that a shuttle <NUM> travelling there along may be selectively transferred between the first inter-aisle shuttle outlet track <NUM> and the second inter-aisle shuttle outlet track <NUM> (e.g., from the first inter-aisle shuttle outlet track <NUM> to the second inter-aisle shuttle outlet track <NUM> and/or from the second inter-aisle shuttle outlet track <NUM> to the first inter-aisle shuttle outlet track <NUM>) in order to avoid a shuttle interference that is detected along one of the plurality of inter-aisle shuttle outlet tracks <NUM>. For example, the parallel passing lanes defined by the configuration of the plurality of inter-aisle shuttle outlet tracks <NUM> enables the plurality of shuttles <NUM> provided within the rack arrangement level <NUM> to access each of the plurality of lifts <NUM> for executing various storage and/or retrieval operations, while avoiding shuttle traffic bottlenecks that impede the shuttle recirculation traffic flow pattern during the use of one or more of the lifts <NUM> by using the passing lane configuration of the second inter-aisle shuttle outlet track <NUM> to facilitate the at least substantially continuous flow of shuttle traffic along the plurality of inter-aisle shuttle outlet tracks <NUM>.

As a non-limiting example, <FIG> is a flowchart that illustrates an exemplary operation of an automated storage and retrieval system using a unidirectional shuttle traffic flow pattern and a plurality of parallel inter-aisle shuttle outlet tracks, such described herein in reference to <FIG>, in accordance with various embodiments. Referring to Block <NUM> of <FIG>, the exemplary method <NUM> of operating the automated storage and retrieval system <NUM> includes accessing, via a first shuttle, a first vertical lift of a plurality of vertical lifts by causing the first shuttle to travel from a first storage aisle to a first lift interface position defined along a first inter-aisle shuttle outlet track. Referring now to Block <NUM> of <FIG>, the method <NUM> of operating the AS/RS <NUM> includes determining that the first shuttle is stopped along the first inter-aisle outlet track at a first lift interface position. Referring now to Block <NUM>, the method <NUM> further includes identifying a second shuttle traveling along the first inter-aisle outlet track in an upstream position from the first shuttle relative to the unidirectional shuttle traffic flow pattern of the first inter-aisle outlet track. The method <NUM> further includes causing the second shuttle to transfer from the first inter-aisle outlet track to a second inter-aisle outlet track arranged in an at least substantially parallel configuration relative to the first inter-aisle shuttle outlet track, as shown at Block <NUM>. Referring now to Block <NUM>, the method <NUM> of operating the AS/RS <NUM> may include, upon determining that the second shuttle has moved along the second inter-aisle shuttle outlet track so as to pass the first shuttle, causing the second shuttle to transfer from the second inter-aisle outlet track to the first inter-aisle outlet track. Further, the method <NUM> may include accessing, via the second shuttle, a second vertical lift of the plurality of vertical lifts by causing the second shuttle to travel to a second lift interface position defined along the first inter-aisle shuttle outlet track, wherein the second lift interface position is arranged downstream from the first lift interface position along the first inter-aisle shuttle outlet track, as shown at Block <NUM>.

Although the plurality of inter-aisle shuttle outlet tracks <NUM> shown in the exemplary embodiment depicted in <FIG> comprises two inter-aisle shuttle outlet tracks (e.g., the first inter-aisle shuttle outlet track <NUM> and the second inter-aisle shuttle outlet track <NUM>), it should be understood that the plurality of inter-aisle shuttle outlet tracks <NUM> may comprise at least substantially more than two inter-aisle shuttle outlet tracks arranged in an at least substantially parallel configuration so as to embody parallel passing lanes. As a non-limiting example, in various embodiments, the plurality of inter-aisle shuttle outlet tracks <NUM> may comprise three, four, five, seven, ten, or any number of inter-aisle shuttle outlet tracks sufficient to facilitate the operability of the AS/RS described herein.

Further, in various embodiments, the selective transfer of a shuttle <NUM> between the plurality of inter-aisle shuttle outlet tracks <NUM> (e.g., from the first inter-aisle shuttle outlet track <NUM> to the second inter-aisle shuttle outlet track <NUM>, or from the second inter-aisle shuttle outlet track <NUM> to the first inter-aisle shuttle outlet track <NUM>) may be enabled by one or more transfer tracks extending between the first inter-aisle shuttle outlet track <NUM> and the second inter-aisle shuttle outlet track <NUM>. For example, in various embodiments, one or more of the transfer tracks 201a, 201b may enable a bidirectional traffic flow therethrough, such that a shuttle <NUM> traveling along the plurality of inter-aisle shuttle outlet tracks <NUM> may be transferred in either a first transfer direction from the first inter-aisle shuttle outlet track <NUM> to the second inter-aisle shuttle outlet track <NUM>, or a second transfer direction from the second inter-aisle shuttle outlet track <NUM> to the first inter-aisle shuttle outlet track <NUM>. In various embodiments, the one or more transfer tracks 201a, 201b may be defined within the plurality inter-aisle shuttle outlet tracks <NUM>, as illustrated in the exemplary rack arrangement level <NUM> shown in <FIG>. Alternatively, or additionally, as illustrated in the exemplary rack arrangement level <NUM> shown in <FIG>, the one or more transfer tracks 201a, 201b may comprise distinct shuttle track guide segments extending in an at least partially perpendicular direction between the first and second inter-aisle shuttle outlet tracks <NUM>, <NUM>.

As further illustrated in <FIG>, the plurality of shuttle guide tracks provided within an exemplary rack arrangement level <NUM> of an AS/RS <NUM> includes a shuttle transport track <NUM> extending between the plurality of inter-aisle shuttle outlet tracks <NUM> and the inter-aisle shuttle inlet track <NUM> so as to facilitate transportation of the plurality of shuttles <NUM> from the plurality of inter-aisle shuttle outlet tracks <NUM> to the inter-aisle shuttle inlet track <NUM>. In various embodiments, the shuttle transport track <NUM> may be defined at least in part by a track length that extends between a first track end connected to one or more of the plurality of inter-aisle shuttle outlet tracks <NUM> and a second track end connected to the inter-aisle shuttle inlet track <NUM>. As illustrated, an exemplary shuttle transport track <NUM> is configured to enable shuttle traffic along the track length thereof so as to define a portion of a looped track circuit and facilitate a shuttle recirculation traffic flow pattern relative to one or more storage aisles <NUM> provided within a given rack arrangement level <NUM> of an AS/RS <NUM>. As described herein, the shuttle transport track <NUM> is configured to define a unidirectional shuttle traffic flow pattern along the track length thereof. For example, the shuttle transport track <NUM> may be configured such that exemplary shuttles <NUM> travelling along the shuttle transport track <NUM> (e.g., from the plurality of inter-aisle shuttle outlet tracks <NUM> to the inter-aisle shuttle inlet track <NUM>) may move in a second longitudinal direction <NUM>. As illustrated, the second longitudinal direction <NUM> may be defined by a longitudinal direction that is at least partially opposite the first longitudinal direction <NUM> defined by the aisle track <NUM> of a storage aisle <NUM>, such as, for example, in the positive-y direction, as illustrated. For example, as shown, the shuttle transport track <NUM> may be configured to facilitate movement of a shuttle <NUM> there along in the second longitudinal direction <NUM> in order to direct the movement of the shuttle <NUM> received from the plurality of inter-aisle shuttle outlet tracks <NUM> towards the first aisle end <NUM> of the aisle track <NUM> of storage aisle <NUM> (e.g., towards the inter-aisle shuttle inlet track <NUM>).

Further, the plurality of shuttle guide tracks provided within an exemplary rack arrangement level <NUM> of an AS/RS <NUM> includes an inter-aisle shuttle inlet track <NUM> extending between the shuttle transport track <NUM> and a first aisle end <NUM> of the aisle rack <NUM> of each of the storage aisles <NUM> defined within the rack arrangement level <NUM>. The inter-aisle shuttle inlet track <NUM> is configured to operatively connect the shuttle transport track <NUM> to aisle track <NUM> of a storage aisle <NUM> (e.g., the first aisle end <NUM>) in order to facilitate transportation of the plurality of shuttles <NUM> from shuttle transport track <NUM> to the aisle track <NUM> of a particular storage aisle <NUM>. In various embodiments, the inter-aisle shuttle inlet track <NUM> may be defined at least in part by a track length that extends between a first track end connected to the shuttle transport track <NUM> and a second track end connected to the first aisle end <NUM> of an aisle track <NUM> defining part of a storage aisle <NUM>. As illustrated, an exemplary inter-aisle shuttle inlet track <NUM> is configured to enable shuttle traffic along the track length thereof so as to define a portion of a looped track circuit, as described herein, and facilitate a shuttle recirculation traffic flow pattern relative to one or more storage aisles <NUM> provided within a given rack arrangement level <NUM> of an AS/RS <NUM>. For example, the inter-aisle shuttle inlet track <NUM> may be arranged so as to extend in a direction that at least substantially intersects a first aisle end <NUM> of each of the storage aisles <NUM> provided within a rack arrangement level <NUM> (e.g., in an at least substantially a perpendicular direction relative to the aisle length). Accordingly, in various embodiments, the inter-aisle shuttle inlet track <NUM> may be at least substantially immediately upstream from each of the aisle track <NUM> provided within the rack arrangement level <NUM> such that a corresponding storage aisle <NUM> may selectively be accessed by a shuttle <NUM> via the inter-aisle shuttle inlet track <NUM>. As described herein, the inter-aisle shuttle inlet track <NUM> is configured to define a unidirectional shuttle traffic flow pattern along the track length thereof. For example, the inter-aisle shuttle inlet track <NUM> may be configured such that exemplary shuttles <NUM> travelling along the inter-aisle shuttle inlet track <NUM> (e.g., from the shuttle transport track <NUM> to an aisle track <NUM> of a particular storage aisle <NUM>) may move in a second lateral direction <NUM>. As illustrated, the second lateral direction <NUM> may be defined by a lateral direction that is at least partially opposite the first lateral direction <NUM> defined by the plurality of inter-aisle shuttle outlet tracks <NUM>, such as, for example, the positive-x direction, as illustrated. For example, as shown, the inter-aisle shuttle inlet track <NUM> may be configured to facilitate movement of a shuttle <NUM> there along in the second lateral direction <NUM> in order to direct the movement of the shuttle <NUM> received from the shuttle transport track <NUM> towards a first aisle end <NUM> of an aisle track <NUM> of storage aisle <NUM>. For example, a shuttle <NUM> travelling along the inter-aisle shuttle inlet track <NUM> in the second lateral direction <NUM> according to the unidirectional shuttle traffic flow pattern thereof may be directed to one or more positions along the track length of the inter-aisle shuttle inlet track <NUM> that are connected to a first aisle end <NUM> of an aisle track <NUM>, such that the shuttle <NUM> may access the corresponding storage aisle <NUM> therefrom. The aisle track <NUM> of each storage aisle <NUM> may be configured to receive a shuttle <NUM> transferred thereto from the inter-aisle shuttle inlet track <NUM> such that movement of the shuttle <NUM> is redirected from the second lateral direction <NUM> to the first longitudinal direction <NUM> as the shuttle <NUM> travels along the aisle track <NUM>.

<FIG> illustrates a schematic view of an exemplary automated storage and retrieval system according to various embodiments described herein. In particular, <FIG> illustrates a schematic view of an exemplary rack arrangement level <NUM> of an AS/RS <NUM>, the rack arrangement level <NUM> comprising a plurality of storage aisles <NUM>. In various embodiments, the rack arrangement of an exemplary AS/RS <NUM> may comprise a plurality of storage racks arranged so as to define a plurality of adjacent storage rack pairs, each adjacent storage rack pair defining a central aisle provided between the adjacent storage racks, as described herein. In such an exemplary circumstance, as shown in the exemplary embodiment illustrated in <FIG>, an exemplary rack arrangement level <NUM> comprises a plurality of storage aisles <NUM> provided therein, each of which may be accessible to a shuttle <NUM> configured traveling along the plurality of shuttle guide tracks within the rack arrangement level <NUM> according to the shuttle recirculation traffic flow pattern, as described herein. The exemplary rack arrangement level <NUM> illustrated in <FIG> includes a plurality of storage aisle <NUM> comprising a first storage aisle 100a, a second storage aisle 100b, a third storage aisle 100c, and a fourth storage aisle 100d. In various embodiments, each of the plurality of storage aisles <NUM> within a rack arrangement level <NUM> may comprise a first storage shelf and a second storage shelf of adjacent storage racks, respectively. In the illustrated exemplary embodiment, the first storage aisle 100a comprises a first storage shelf <NUM> and a second storage shelf <NUM>, the second storage aisle 100b comprises a third storage shelf <NUM> and a fourth storage shelf <NUM>, the third storage aisle 100c comprises a fifth storage shelf <NUM> and a sixth storage shelf <NUM>, and the fourth storage aisle 100d comprises a seventh storage shelf <NUM> and an eight storage shelf <NUM>. Further, the first, second, third, and fourth storage aisles 100a, 100b, 100c, and 100d of the plurality of storage aisles <NUM> provided in the rack arrangement level <NUM> comprise a first aisle track 110a, a second aisle track 110b, a third aisle track 110c, and a fourth aisle track 110d, respectively, each of which may extend along a respective aisle length between the two storage shelves of the corresponding storage aisle in at least substantially the same longitudinal direction as the storage shelves provided on either side thereof.

In various embodiments, the rack arrangement of the AS/RS <NUM> may comprise a plurality of racks provided in a laterally distributed arrangement wherein each of the plurality of racks is arranged in an at least substantially parallel configuration relative to one another, such that each of the respective storage shelves provided within the rack arrangement level <NUM> (e.g., first storage shelf <NUM>, second storage shelf <NUM>, third storage shelf <NUM>, fourth storage shelf <NUM>, fifth storage shelf <NUM>, sixth storage shelf <NUM>, seventh storage shelf <NUM>, eighth storage shelf <NUM>) are similarly arranged in an at least substantially parallel configuration relative to one another. Accordingly the storage aisles of the plurality of storage aisles <NUM> may be arranged in a parallel configuration, wherein the aisle length of each of the plurality of storage aisles <NUM> is parallel to each of the other aisle lengths defined by the other storage aisles of the plurality <NUM>. For example, as illustrated in <FIG>, the first, second, third, and fourth storage aisles 100a, 100b, 100c, 100d may each extend in an at least substantially longitudinal direction, such as, for example, in the y-direction, as illustrated.

According to the invention, an exemplary rack arrangement level <NUM> is configured such that each of the plurality of storage aisles <NUM> provided within the rack arrangement level <NUM> comprises a respective aisle track 110a, 110b, 110c, 110d that extends along an aisle length thereof in a longitudinal direction that is at least substantially parallel to the adjacent storage shelves of the corresponding storage aisle. As illustrated in <FIG>, the aisle tracks 110a, 110b, 110c, 110d of each of the plurality of storage aisles 100a, 100b, 100c, 100d are configured to enable shuttle traffic of at least one shuttle provided within the storage aisle along the aisle length thereof in a first shuttle travel direction in order to facilitate movement of one or more of the plurality of automated shuttles <NUM> to and/or from one or more storage locations provided within the storage aisle <NUM>. For example, as illustrated, each of the aisle tracks 110a, 110b, 110c, 110d are configured to enable shuttle traffic of at least one shuttle <NUM> along the respective aisle length thereof in a first shuttle travel direction, such as, for example, the first longitudinal direction <NUM> (e.g., in the negative-x direction, as illustrated). In various embodiments, each of the plurality of storage aisles <NUM> provided within a rack arrangement level <NUM> is configured to facilitate shuttle transportation along a corresponding aisle track thereof (e.g., aisle tracks 110a, 110b, 110c, 110d) according to a unidirectional shuttle traffic flow pattern, wherein the unidirectional shuttle traffic flow pattern is defined by the movement of each of the plurality of shuttles <NUM> along the corresponding aisle track thereof in at least substantially the same shuttle travel direction, such as, for example, in the first longitudinal direction <NUM>.

According to the invention, an exemplary rack arrangement level <NUM> comprising a plurality of storage aisles <NUM> provided therein comprises a plurality of inter-aisle shuttle outlet tracks <NUM>, as described herein, that extends in a direction is at least substantially perpendicular to at least a portion of the parallelly-configured plurality of storage aisles <NUM> (e.g., in a lateral direction, such as the x-direction, as illustrated) and is arranged so as to be connected to each of the plurality of storage aisles <NUM> (e.g., at the second aisle end of each respective aisle track). Accordingly, the plurality of inter-aisle shuttle outlet tracks <NUM> comprises a second inter-aisle shuttle outlet track <NUM> that is at least substantially immediately downstream from each of the plurality of storage aisles <NUM> within the rack arrangement level <NUM> such that a plurality of shuttles <NUM> travelling along any one of the aisle tracks 110a, 110b, 110c, 110d according to the unidirectional shuttle traffic flow pattern defined by each of the plurality of storage aisles <NUM>, as described herein, may be received by the second inter-aisle shuttle outlet track <NUM> upon plurality of shuttles <NUM> being transported beyond the second aisle end of the aisle track of a storage aisle <NUM>. Further, the first inter-aisle shuttle outlet track <NUM> of the plurality of inter-aisle shuttle outlet tracks <NUM> is configured to facilitate transportation of the plurality of shuttles <NUM> from each of the plurality of storage aisles <NUM> provided within the rack arrangement level <NUM> to one or more of a plurality of vertical lifts <NUM> of the AS/RS <NUM>. The first inter-aisle shuttle outlet track <NUM> defines a vertical lift access track along which a plurality of shuttles <NUM> may be received from at least one of the plurality of storage aisles <NUM> (e.g., 100a, 100b, 100c, 100d) and transported according to a unidirectional shuttle traffic flow pattern in a first latitude direction <NUM> (e.g., in the negative-x direction, as illustrated) to one of a plurality of lift interface positions defined along the first inter-aisle shuttle outlet track <NUM>, as described herein, from which a shuttle <NUM> may access an adjacent lift 200a, 200b, 200c, 200d of the plurality of lifts <NUM>.

As described herein in further detail in reference to the plurality of inter-aisle shuttle outlet tracks <NUM> of the exemplary rack arrangement level <NUM> depicted in <FIG>, the plurality of inter-aisle shuttle outlet tracks <NUM> is configured to facilitate transportation of the plurality of shuttles <NUM> from the plurality of storage aisles <NUM> to one or more of the plurality of lifts <NUM>, or, alternatively and/or additionally, to the shuttle transport track <NUM> as the result of the shuttle recirculation traffic flow pattern defined within the rack arrangement level <NUM>. For example, the first inter-aisle shuttle outlet track <NUM> and the second inter-aisle shuttle outlet track <NUM> may be configured to facilitate a respective unidirectional shuttle traffic flow pattern defined at least in part along a respective track length thereof in the first lateral direction <NUM> (e.g., the negative-x direction, as illustrated). As described herein, the second inter-aisle shuttle outlet track <NUM> spans laterally across each of the plurality of storage aisles <NUM> provided within the rack arrangement system <NUM>, and is arranged in an at least substantially parallel and adjacent configuration relative to the first inter-aisle shuttle outlet track <NUM> such that the second inter-aisle shuttle outlet track <NUM> embodies a parallel passing track that functions as an alternative shuttle travel path to that of the first inter-aisle shuttle outlet track <NUM>. The plurality of inter-aisle shuttle outlet tracks <NUM> is configured such that a shuttle <NUM> travelling there along may be selectively transferred between the first inter-aisle shuttle outlet track <NUM> and the second inter-aisle shuttle outlet track <NUM> in order to facilitate an at least substantially continuous (e.g., unobstructed) shuttle traffic flow towards the shuttle transport track <NUM>. Further, an exemplary second inter-aisle shuttle outlet track <NUM> embodying a parallel passing track may be utilized for transportation of at least a portion of the plurality of shuttles <NUM> determined to be executing a portion of a storage and/or retrieval operation that does not require access to one of the plurality of lifts <NUM>. For example, such exemplary shuttles <NUM> may be transported along the second inter-aisle shuttle outlet track <NUM> directly to the shuttle transport track <NUM> without being transferred to the first inter-aisle shuttle outlet track <NUM>, thereby minimizing the risk that the movement of said exemplary shuttles <NUM> along the plurality of inter-aisle shuttle outlet tracks <NUM> will be impeded and/or slowed by another shuttle <NUM> of the plurality that is stopped at a lift interface position along the first inter-aisle shuttle outlet track <NUM>.

As further illustrated in <FIG>, an exemplary rack arrangement level <NUM> comprising a plurality of storage aisles <NUM> provided therein comprises an inter-aisle shuttle inlet track <NUM>, as described herein, that extends in a direction is at least substantially perpendicular to at least a portion of the parallelly-configured plurality of storage aisles <NUM> (e.g., in a lateral direction, such as the x-direction, as illustrated) and is arranged so as to be connected to each of the plurality of storage aisles <NUM> (e.g., at the first aisle end of each respective aisle track). The inter-aisle shuttle inlet track <NUM> is configured to operatively connect the shuttle transport track <NUM> to each of the plurality of storage aisles 100a, 100b, 100c, 100d (e.g., each of the respective aisle tracks 110a, 110b, 110c, 110d) at a respective first aisle end thereof in order to facilitate transportation of the plurality of shuttles <NUM> from shuttle transport track <NUM> to a particular storage aisle of the plurality of storage aisles <NUM>. In various embodiments, the inter-aisle shuttle inlet track <NUM> may be defined at least in part by a track length that extends between a first track end connected to the shuttle transport track <NUM> and a second track end operatively connected to first aisle end of the storage aisle of the plurality <NUM> that is arranged in a position farthest away from the shuttle transport track <NUM>, such as, for example, the fourth storage aisle 100d in the exemplary rack arrangement <NUM> illustrated in <FIG>. Accordingly, in various embodiments, the inter-aisle shuttle inlet track <NUM> may be arranged at least substantially immediately upstream (e.g., relative to the shuttle recirculation traffic flow pattern, as described herein) from each of the aisle tracks 110a, 110b, 110c, 110d provided within the rack arrangement level <NUM> such that one or more shuttles <NUM> instructed (e.g., via a central controller of the AS/RS <NUM>) to execute a storage and/or retrieval operation with respect to an object stored at a storage location provided within a particular storage aisle of the plurality <NUM> may travel along the inter-aisle shuttle inlet track <NUM> in the second lateral direction <NUM> according to the unidirectional shuttle traffic flow pattern thereof to a position at least substantially adjacent a first aisle end of the particular storage aisle, where the one or more shuttles <NUM> may turn into the particular storage aisle comprising the designated storage location.

In various embodiments, the plurality of vertical lifts <NUM> of an exemplary AS/RS <NUM> may include a first portion of the plurality of vertical lifts <NUM> that may be operatively connected to a first conveyor configured to transport objects between the AS/RS <NUM> and a first remote location, and a second portion of the plurality of vertical lifts <NUM> that may be operatively connected to a second conveyor configured to transport objects between the AS/RS <NUM> and a second remote location. For example, as illustrated, the plurality of vertical lifts <NUM> may comprise a first portion of the plurality of vertical lifts <NUM> including a first vertical lift 200a and a second vertical lift 200b that are operatively connected to a first conveyor <NUM> that is configured to transport objects between the AS/RS <NUM> and a first remote conveyor <NUM>. As illustrated, the plurality of vertical lifts <NUM> may further include a second portion of vertical lifts including a third vertical lift 200c and a third vertical lift 200d that are operatively connected to a second conveyor <NUM> that is configured to transport objects between the AS/RS <NUM> and a second remote conveyor <NUM>. In such an exemplary circumstance, one or more shuttles of the plurality of shuttles <NUM> instructed to execute a storage and/or retrieval operation that requires accessing either the first vertical lift 200a or the second vertical lift 200b may be selectively transported along the second inter-aisle shuttle outlet track <NUM> in the first lateral direction <NUM> so as to pass the lift interface positions corresponding to the third vertical lift 200c and the fourth vertical lift 200d. The one or more shuttles <NUM> may be selectively transferred from the second inter-aisle shuttle outlet track <NUM> to the first inter-aisle shuttle outlet track <NUM> so as to avoid track interferences caused by other shuttles of the plurality <NUM> being positioned in the lift interface positions corresponding to the third vertical lift 200c and the fourth vertical lift 200d, while facilitating the transportation of the one or more shuttles to a particular one of the designated vertical lifts 200a, 200b.

Similarly, in an exemplary circumstance wherein a shuttle <NUM> is executing a storage and/or retrieval operation that requires the shuttle <NUM> to access a particular lift of the plurality of lifts <NUM>, such as, for example, the fourth lift 200d, the shuttle <NUM> may be selectively transported along the inter-aisle shuttle inlet track <NUM> to a particular storage aisle of the plurality of storage aisles <NUM>, such as, for example, the fourth storage aisle 100d, that defines a portion of the shuttle recirculation traffic flow pattern defined within the rack arrangement level <NUM> that is in an upstream position relative to the lift interface position corresponding to the particular vertical lift to be accessed (e.g., the fourth lift 200d).

In various embodiments, the plurality of shuttles provided within a rack arrangement level of an exemplary AS/RS may include one or more shuttles that are at least temporarily in a standby configuration wherein the one or more shuttles are not being used to execute a storage and/or retrieval operation at a given time. For example, an exemplary AS/RS may comprise a central controller that is in communication with each of the plurality of shuttles <NUM> and configured to determine an optimal number of shuttles of the plurality <NUM> to be used in operation within a particular rack arrangement level at a given time based at least in part on an identified and/or estimated bandwidth of the AS/RS <NUM> (e.g., within the particular rack arrangement level at that time. For example, in various embodiments, the central controller of the AS/RS may identify that less than the total number of shuttles <NUM> in the plurality of shuttles provided at a rack arrangement level is needed to execute one or more storage and/or retrieval operations, and therefore, may cause at least a portion of the plurality of shuttles <NUM> to be transported to a shuttle storage position defined along a portion of the shuttle travel racks of the rack arrangement level. Further, in various embodiments, the central controller of the AS/RS may identify that the number of shuttles needed to execute one or more storage and/or retrieval operations is more than the total number of shuttles of the plurality <NUM> in operation at a given time, and therefore, may cause one or more shuttles of the plurality <NUM> that are being stored in a shuttle storage position within the rack level arrangement to be dispatched from the shuttle storage position for use in a storage and/or retrieval operation.

<FIG> illustrate various schematic views of exemplary automated storage and retrieval systems that include rack arrangement levels comprising a shuttle storage position according to various embodiments described herein. As illustrated in <FIG>, in various embodiments an exemplary rack arrangement level <NUM> may comprise a shuttle storage position <NUM> that is defined along the shuttle transport track <NUM> thereof. For example, at least a portion of the plurality of shuttles <NUM> provided within the rack arrangement level <NUM> may be at least temporarily stored at a shuttle storage position <NUM> defined along at least a portion of the track length of the shuttle transport track <NUM>. The at least a portion of the plurality of shuttles <NUM> being stored at the shuttle storage position <NUM> along the shuttle transport track <NUM> may be positioned in a serial arrangement along the track length thereof so as to define a queue of shuttles <NUM> that are not executing a storage and/or retrieval operation at a given time. In various embodiments, one or more shuttles <NUM> may be dispatched from the shuttle storage position as needed to execute one or more storage and/or retrieval operations. In such an exemplary circumstance, a central controller of the AS/RS <NUM> may provide instructions to at least the shuttle positioned in a frontmost position (e.g., furthest downstream, as defined along the unidirectional shuttle traffic flow) within the shuttle storage position <NUM> that may cause the shuttle to be transported (e.g., dispatched) from the shuttle storage position <NUM> to a designated storage aisle of the plurality <NUM> (e.g., via the inter-aisle shuttle inlet track <NUM>). For example, upon successfully executing the storage and/or retrieval operation, the shuttle <NUM> may be transported to the shuttle transport track <NUM> (e.g., via the plurality of inter-aisle shuttle outlet tracks <NUM>) such that it may returned to the shuttle storage position <NUM>. Such an exemplary shuttle <NUM> may be returned to the shuttle storage position <NUM> such that it is arranged in a back-most position in the queue of shuttles <NUM> provided within the shuttle storage position <NUM>.

As a further non-limiting example, <FIG> illustrates an exemplary rack arrangement level <NUM> comprising a shuttle storage position <NUM> that is defined along a secondary shuttle transport track 130a. In various embodiments, an exemplary rack arrangement level <NUM> may comprise a shuttle transport track <NUM>, as described herein in further detail with respect to <FIG> and <FIG>, and a secondary shuttle transport track 130a along which at least a portion of the plurality of shuttles <NUM> provided within the rack arrangement level <NUM> may be at least temporarily stored at a shuttle storage position <NUM>. For example, the at least a portion of the plurality of shuttles <NUM> being stored along the secondary shuttle transport track 130a may be positioned in a serial arrangement along the track length of the secondary shuttle transport track 130a so as to define a queue of shuttles <NUM> that are not executing a storage and/or retrieval operation at a given time. The secondary shuttle transport track 130a may comprise a distinct segment of shuttle guide track that is at least substantially separate from the shuttle transport track <NUM> such that the shuttles <NUM> provided at the shuttle storage position <NUM> along the secondary shuttle transport track 130a do not interrupt, interfere with, and/or otherwise obstruct the shuttle recirculation traffic flow pattern defined in part by the shuttle transportation track <NUM>. In various embodiments, upon determining that an additional shuttle <NUM> is required in order to execute a storage and/or retrieval operation, a central controller of the AS/RS <NUM> may provide instructions to the shuttle positioned in a frontmost position (e.g., furthest downstream, as defined along the unidirectional shuttle traffic flow) within the shuttle storage position <NUM> that may cause the shuttle to be transported (e.g., dispatched) from the shuttle storage position <NUM> to a designated storage aisle of the plurality <NUM> (e.g., via the inter-aisle shuttle inlet track <NUM>).

<FIG> is a flowchart that illustrates an exemplary operation of an automated storage and retrieval system using a unidirectional shuttle traffic flow pattern, such described herein in reference to <FIG>, in accordance with various embodiments. Referring to Block <NUM> of <FIG>, the exemplary method <NUM> of operating the automated storage and retrieval system <NUM> includes causing a first shuttle to travel to a first storage location provided within the first storage aisle such that the first shuttle moves along an aisle track of the first storage aisle in a first shuttle travel direction. In various embodiments, wherein the AS/RS <NUM> comprises a plurality of storage aisles, causing a first shuttle to travel to a first storage location provided within the first storage aisle may comprise selectively causing the first shuttle to travel to a storage location within the first storage aisle from the plurality of storage aisles based at least in part on a relative position of the first storage aisle within a unidirectional shuttle recirculation traffic flow pattern defined by the automated storage and retrieval system. Referring now to Block <NUM> of <FIG>, the method <NUM> of operating the AS/RS <NUM> includes causing a second shuttle to travel to a second storage location provided within the first storage aisle such that the second shuttle moves along the aisle track of the first storage aisle in the first shuttle travel direction and such that both the first shuttle and the second shuttle are positioned within the first storage aisle at a first instance. As described herein, the unidirectional shuttle traffic flow pattern defined by the first storage aisle enables an operation wherein the first shuttle executing a first materials handling operation and the second shuttle executing a second materials handling operation may each be positioned along the aisle track of the first storage aisle at the same time by eliminating the possibility that two shuttles simultaneously positioned within the same storage aisle are executing instructions to move in opposing directions and/or along conflicting shuttle traffic paths. Referring now to Block <NUM> of <FIG>, the method <NUM> of operating the AS/RS <NUM> includes causing the first shuttle to travel in the first shuttle travel direction from the first storage location to a first storage aisle outlet of the first storage aisle. Further, in reference to Block <NUM> of <FIG>, the method <NUM> of operating the AS/RS <NUM> may include causing the second shuttle to travel along the aisle track in the first shuttle travel direction to the first storage aisle outlet. As illustrated in the exemplary embodiment shown in <FIG>, the first storage aisle outlet of the first storage aisle <NUM> may be defined by the second aisle end <NUM>. Further, in various embodiments, the method <NUM> of operating the AS/RS <NUM> may include, upon determining that that the first shuttle has executed a first materials handling operation, providing instructions to the first shuttle to execute a second materials handling operation, as shown at Block <NUM> of <FIG>. In various embodiments, providing instructions to the first shuttle to execute the second materials handling operation may comprise causing the first shuttle to travel to a third storage location provided within the first storage aisle such that the first shuttle moves along the aisle track of the first storage aisle in the first shuttle travel direction.

Claim 1:
An automated storage and retrieval system comprising:
a plurality of storage aisles (<NUM>, 100a, 100b, 100c), each storage aisle comprising a plurality of storage locations (<NUM>, 101a, 101b, 101n) positioned adjacent to an aisle track (<NUM>, 110a, 110b, 110c, 110d) that extends along an aisle length;
a plurality of shuttles (<NUM>) configured to travel throughout the automated storage and retrieval system to execute a materials handling operation;
at least one vertical lift (<NUM>);
a plurality of inter-aisle shuttle outlet tracks (<NUM>) configured to facilitate shuttle traffic flow in at least substantially the same direction, the plurality of inter-aisle shuttle outlet tracks comprising:
a first inter-aisle shuttle outlet track (<NUM>) configured to facilitate shuttle traffic flow to the at least one vertical lifts (<NUM>) via at least one lift interface position defined along the first inter-aisle shuttle outlet track (<NUM>);
a second inter-aisle shuttle outlet track (<NUM>) arranged in an at least substantially parallel configuration relative to the first inter-aisle shuttle outlet track (<NUM>),
an inter-aisle shuttle inlet track (<NUM>) operatively connected to a respective aisle inlet end of each of the plurality of storage aisles; and
a shuttle transport track (<NUM>) extending from the plurality of inter-aisle shuttle outlet tracks (<NUM>) to the inter-aisle shuttle inlet track (<NUM>),
wherein the aisle track (<NUM>, 110a, 110b, 110c, 110d) of each storage aisle of the plurality of storage aisles, the shuttle transport track (<NUM>), the inter-aisle shuttle inlet track (<NUM>), and the plurality of inter-aisle shuttle outlet track define a looped track circuit configured to facilitate shuttle traffic flow along the aisle length thereof in a first shuttle travel direction such that each of the plurality of storage aisles is defined in part by a unidirectional shuttle traffic flow pattern,
the automated storage and retrieval system being characterized in that
the plurality of inter-aisle shuttle outlet tracks is configured to enable a transfer of at least one of the plurality of shuttles (<NUM>) between the first inter-aisle shuttle outlet track (<NUM>) and the second inter-aisle shuttle outlet track (<NUM>) at one or more transfer locations along the first inter-aisle shuttle outlet track (<NUM>).