Weighing method

Abstract

A method of weighing a storage container to determine an amount of items in the storage container, in particular to determine the amount of items in a source storage container after completion of a picking operation at a picking station that transfers items from the source storage container to a target container, such as to a delivery package.

Description

Technical Field

[0001] The present invention relates to an automatic storage and retrieval system for storing and retrieving containers, and more particularly to a method for weighing a storage container to determine the content of the container. Background Art

[0002] FIG. 1 discloses a prior art automated storage and retrieval system having a frame structure 100 , and FIGS. 2 , 3 and 4 disclose three different prior art container handling vehicles 201 , 301 , 401 suitable for operating on such a system 1 .

[0003] The frame structure 100 comprises upright members 102 and a storage volume comprising storage columns 105 arranged in rows between the upright members 102. In these storage columns 105, storage containers 106 (also called boxes) are stacked one on top of the other to form stacks 107. The members 102 may generally be made of metal, such as extruded aluminum profiles.

[0004] The frame structure 100 of the automatic storage and retrieval system 1 includes a rail system 108 arranged across the top of the frame structure 100, on which a plurality of container handling vehicles 201, 301, 401 can be operated to lift storage containers 106 from the storage row 105 and lower the storage containers 106 into the storage row, and can also transport the storage containers 106 above the storage row 105. The rail system 108 includes a first parallel rail group 110 and a second parallel rail group 111, the first parallel rail group is arranged to guide the container handling vehicles 201, 301, 401 to move in a first direction X across the top of the frame structure 100, and the second parallel rail group is arranged perpendicular to the first rail group 110 to guide the container handling vehicles 201, 301, 401 to move in a second direction Y perpendicular to the first direction X. The containers 106 stored in the row 105 are accessed by the container handling vehicles 201, 301, 401 through access openings 112 in the rail system 108. The container handling vehicles 201 , 301 , 401 can move laterally above the storage row 105 , ie in a plane parallel to the horizontal plane XY.

[0005] Upright members 102 of frame structure 100 may be used to guide storage containers during the process of raising and lowering containers from and into row 105. Stack 107 of containers 106 is generally self-supporting.

[0006] Each container handling vehicle 201, 301, 401 of the prior art comprises a body 201a, 301a, 401a and first and second wheel sets 201b, 201c, 301b, 301c, 401b, 401c, which respectively enable the container handling vehicle 201, 301, 401 to move laterally in the X direction and in the Y direction. In Figures 2, 3 and 4, the two wheels in each set are fully visible. The first wheel set 201b, 301b, 401b is arranged to engage with two adjacent tracks of the first track set 110, and the second wheel set 201c, 301c, 401c is arranged to engage with two adjacent tracks of the second track set 111. At least one of the wheel sets 201b, 201c, 301b, 301c, 401b, 401c can be raised and lowered so that the first wheel set 201b, 301b, 401b and / or the second wheel set 201c, 301c, 401c can engage with the corresponding track set 110, 111 at any time.

[0007] Each container handling vehicle 201, 301, 401 of the prior art also includes a lifting device for vertically transporting storage containers 106, for example, lifting and lowering storage containers 106 from and into the storage row 105. The lifting device includes one or more clamping / engaging devices adapted to engage the storage container 106, and these clamping / engaging devices can be lowered from the vehicle 201, 301, 401 so that the clamping / engaging devices can be adjusted relative to the position of the vehicle 201, 301, 401 in a third direction Z orthogonal to the first direction X and the second direction Y. Components of the clamping device of the container handling vehicle 301, 401 are indicated by reference numerals 304, 404 in Figures 3 and 4. The clamping device of the container handling device 201 is located in the vehicle body 201a in Figure 2 and is therefore not shown.

[0008] Conventionally, and also for the purposes of the present application, Z=1 identifies the uppermost level available for storage containers below the rails 110, 111, i.e., the level immediately below the rail system 108, Z=2 identifies the second level below the rail system 108, Z=3 identifies the third level, and so on. In the exemplary prior art disclosed in FIG. 1, Z=8 identifies the lowest, bottom level of storage containers. Similarly, X=1...n and Y=1...n identify the position of each storage column 105 in a horizontal plane. Thus, as an example, using the Cartesian coordinate system X, Y, Z shown in FIG. 1, the storage container identified as 106' in FIG. 1 can be said to occupy storage position X=17, Y=1, Z=6. The container handling vehicles 201, 301, 401 can be said to travel in level Z=0, and the individual storage columns 105 can be identified by their X and Y coordinates. Thus, the storage containers shown in FIG. 1 extending above the rail system 108 can also be said to be arranged in level Z=0.

[0009] The storage volume of the frame structure 100 is generally referred to as a grid 104, and the possible storage positions within the grid are referred to as storage cells. Each storage column can be identified by its position in the X and Y directions, and each storage cell can be identified by the container number in the X, Y and Z directions.

[0010] Each container handling vehicle 201, 301, 401 of the prior art includes a storage compartment or space for receiving and loading the storage container 106 when transporting the storage container 106 across the track system 108. The storage space may include a cavity arranged inside the vehicle body 201a, 401a, as shown in Figures 2 and 4, as described in, for example, WO 2015 / 193278A1 and WO 2019 / 206487A1, the contents of which are incorporated herein by reference.

[0011] Figure 3 shows an alternative configuration of a container handling vehicle 301 having a cantilever structure. Such a vehicle is described in detail, for example, in NO 317366, the contents of which are also incorporated herein by reference.

[0012] The cavity container handling vehicle 201 shown in Figure 2 may have a footprint that covers an area having dimensions in the X and Y directions, which area is generally equal to the lateral extent of the storage row 105, for example, as described in WO 2015 / 193278A1, the contents of which are incorporated herein by reference. The term "lateral" as used herein may refer to "horizontally".

[0013] Alternatively, the footprint of the cavity container handling vehicle 401 can be larger than the lateral area defined by the storage row 105 shown in Figures 1 and 4, for example, as disclosed in WO 2014 / 090684A1 or WO 2019 / 206487A1.

[0014] The track system 108 generally includes a track with a groove, and the wheels of the vehicle run in the groove. Alternatively, the track may include an upwardly protruding element, where the wheels of the vehicle include flanges to prevent derailment. These grooves and upwardly protruding elements are collectively referred to as tracks. Each track may include a track, or each track 110, 111 may include two parallel tracks. In other track systems 108, each track in one direction (e.g., X direction) may include a track, and each track in another vertical direction (e.g., Y direction) may include two tracks. Each track 110, 111 may also include two track members fastened together, each track member providing one of a pair of tracks provided by each track.

[0015] WO 2018 / 146304A1 shows a general configuration of a track system 108, which includes tracks and parallel tracks in the X and Y directions, the contents of which are incorporated herein by reference.

[0016] In the frame structure 100, most of the columns 105 are storage columns 105, i.e., columns 105 where storage containers 106 are stored at stacks 107. However, some columns 105 may have other purposes. In FIG. 1 , columns 119 and 120 are special purpose columns used by container handling vehicles 201, 301, 401 to unload and / or pick up storage containers 106 in order to transport the storage containers to access stations (not shown) where storage containers 106 may be accessed from outside the frame structure 100 or transferred out of or into the frame structure 100. In the art, such locations are often referred to as "ports," and the columns in which the ports are located may be referred to as "port columns" 119, 120. Transportation to the access stations may be in any direction, i.e., horizontal, inclined, and / or vertical. For example, storage containers 106 may be placed in random or dedicated rows 105 within the frame structure 100 and then picked up by any container handling vehicle and transported to port rows 119, 120 for further transport to an access station. Transport from the port to the access station may require movement in different directions by means of delivery trucks, trolleys or other transport routes. Note that the term "inclined" refers to the transport of storage containers 106 with a general transport direction between horizontal and vertical.

[0017] In Figure 1, the first port column 119 can be, for example, a dedicated unloading port column, at which the container handling vehicles 201, 301, 401 can unload the storage containers 106 to be transported to the access station or the transfer station, and the second port column 120 can be a dedicated picking port column, at which the container handling vehicles 201, 301, 401 can pick up the storage containers 106 that have been transported from the access station or the transfer station.

[0018] The access station can generally be a picking station or a deposit station 406, where product items are removed from or placed into the storage container 106. In the picking station or the deposit station, the storage container 106 is usually not removed from the automatic storage and retrieval system 1, but is returned to the frame structure 100 again after being accessed. The port can also be used to transfer the storage container to another storage facility (e.g., another frame structure or another automatic storage and retrieval system), a transport vehicle (e.g., a train or a truck), or a production facility.

[0019] A conveying system including a conveyor is typically used to transport the storage containers between the port rows 119, 120 and the access station.

[0020] If the port rows 119, 120 and the access station are located at different levels, the conveying system may include a lifting device with a vertical component for vertically transporting the storage container 106 between the port rows 119, 120 and the access station.

[0021] The conveying system may be arranged to transfer storage containers 106 between different frame structures, for example as described in WO 2014 / 075937 A1, the contents of which are incorporated herein by reference.

[0022] When a storage container 106 stored in one of the columns 105 disclosed in FIG. 1 is to be accessed, one of the container handling vehicles 201, 301, 401 is instructed to take the target storage container 106 from its position and transport it to the discharge port column 119. This operation involves moving the container handling vehicle 201, 301, 401 to a position above the storage column 105 where the target storage container 106 is located, taking the storage container 106 from the storage column 105 using the lifting device (not shown) of the container handling vehicle 201, 301, 401, and transporting the storage container 106 to the discharge port column 119. If the target storage container 106 is located deep in the stack 107, i.e., one or more other storage containers 106 are placed above the target storage container 106, the operation also involves temporarily moving the storage container located above before lifting the target storage container 106 from the storage column 105. This step, sometimes referred to in the art as "digging," may be performed with the same container handling vehicle or one or more other cooperating container handling vehicles that are subsequently used to transport the target storage container to the discharge port row 119. Alternatively or in addition, the automated storage and retrieval system 1 may have a container handling vehicle 201, 301, 401 that is specifically designed for the task of temporarily removing a storage container 106 from a storage row 105. Once the target storage container 106 has been removed from the storage row 105, the temporarily removed storage container 106 may be relocated to the original storage row 105. Alternatively, however, the removed storage container 106 may be relocated to another storage row 105.

[0023] When a storage container 106 is to be stored in one of the rows 105, one of the container handling vehicles 201, 301, 401 is instructed to pick up the storage container 106 from the pickup port row 120 and transport the storage container to a position above the storage row 105 where it is to be stored. After any storage container 106 placed at or above the target position within the stack 107 is removed, the container handling vehicle 201, 301, 401 places the storage container 106 at the desired position. The removed storage container 106 can then be lowered back into the storage row 105 or relocated to another storage row 105.

[0024] In order to monitor and control the automatic storage and retrieval system 1, such as monitoring and controlling the positions of the corresponding storage containers 106 within the frame structure 100, the contents in each storage container 106, and the movement of the container handling vehicles 201, 301, 401, so as to deliver the desired storage container 106 to the desired location at the desired time without causing the container handling vehicles 201, 301, 401 to collide with each other, the automatic storage and retrieval system 1 includes a control system 500, which is generally computerized and generally includes a database for tracking the storage containers 106.

[0025] Container weighing

[0026] Many containers used for storing and retrieving goods in the above-mentioned system contain multiple items. The weight of each individual item is a known variable, as is the weight of the container itself. Therefore, the number of items in the container can be determined by weighing the container. In practice, it is known to weigh the source storage container as a control operation after the picking operation at the picking station to confirm that the correct number of items are removed from the source storage container (S) by the operator and placed in the target container (T). As used herein and in connection with the present invention, the term "picking station" refers to a workstation where a picker accesses the contents of the source storage container (S) in order to remove one or more items or to re-deposit the items into the container. The term picking station should also be understood to include operational infrastructure directly related to the picking station, such as conveyors, access doors, tipping devices, and weighing devices. As used herein and in connection with the present invention, the term "target container" refers to any container to which items from a source container are transferred. An example of a target container is a delivery package. The term "picker" refers to a human worker or an automatic picking device.

[0027] The weight of the source storage container (S) as well as the unit weight and number of items therein are known. Therefore, before picking, the initial weight of the source storage container (S) is known. At the picking station, a predetermined number of items of known weight will be removed from (S) and transferred to (T). Therefore, after the picking is completed, the number of items removed can be determined by weighing the source storage container (S). This operation is currently performed by the weighing equipment of the picking station immediately after / in connection with the picking operation, where the operator confirms that the source storage container (S) has the expected weight before sending the source storage container (S) out of the picking station and returning it to the stacking.

[0028] However, weighing at the picking station immediately after / in connection with the picking operation can introduce a non-negligible delay to the overall effectiveness of the storage and retrieval system, partly because of the known "lag" in the response of the weighing equipment. In practice, the operator has to wait for a period of time before the display of the weighing equipment shows the result of the weighing operation. If the weighing operation is automated, a certain "lag" will be introduced into the system while the control system records the weight. Picking operations are usually completed within a few seconds, so the cumulative effect of even small delays caused by weighing can have a significant impact on the overall throughput of the system. Since the vast majority of picking operations are actually performed correctly, the delay caused by weighing these correctly picked totes may be regarded as wasted time. Summary of the invention

[0029] The invention is set forth and characterized in the independent claim, while the dependent claims describe further characteristics of the invention.

[0030] In one aspect, the present invention relates to a method for weighing a storage container to determine the quantity of items in the storage container, in particular to determine the number of items in a source storage container after a picking operation is completed at a picking station, which transfers the items from the source storage container to a target container, such as to a delivery package.

[0031] In one aspect, the method includes weighing the source storage container (S) after the picking operation is completed to determine the number of items therein. The weighing is performed at a time and / or location away from the picking station and / or the picking operation, thereby eliminating or improving the negative impact on throughput due to any time delay associated with the weighing operation. The control system selects the time and / or location of the weighing operation to avoid or at least reduce any negative impact on throughput. As used herein, the term "at a time removed from the picking operation" should be understood to refer to the amount of time from the completion of the picking operation to the extent that the source container (S) has been sent from the picker so that a new picking operation can be started. In other words, the amount of time that the picker's actions and / or decisions are no longer affected by the weighing of the source container, and a new picking operation can be started without considering the weighing operation. As used herein, the term "at a location away from the picking station" refers to a location that is far enough away from the picking station and a new picking operation can be started without considering the weighing operation.

[0032] Various non-limiting examples of the control system selecting the time and / or location of a weighing operation include:

[0033] Move the source storage container to a buffer associated with the picking station (called the "exit buffer"), but delay the weighing operation to a time calculated to have less negative impact on throughput. The buffer will have a weighing device, such as a section of a conveyor with a weighing area, or a weighing device adjacent to the conveyor, onto which the source container is pushed.

[0034] • Moving the source container to a separate staging area physically away from the picking station with a weighing device similar to the one described above, where the source container waits to be transported back to the pallet.

[0035] • Weighing of source containers on an automated vehicle equipped with a weighing device during their transport from the picking station.

[0036] According to one aspect of the method, the control system of the storage and retrieval system records a "dependency" between the storage container S and the target container T, to which the items from S will be transferred. The term "dependency" refers to any form of conceptual, temporary association between the source container (S) and the target container (T). This dependency can be implemented by a computer, for example, recorded in a memory, or implemented by the control system 500 in a manner known in the art of computerized control systems.

[0037] The "dependency" between S and T includes information about the number of items to be removed from S and placed in T, and the expected weight of S after the picking operation. In one aspect, the expected weight of S is expressed as an expected weight range. The range may be based on a percentage to account for slight deviations or errors in weighing. In another aspect, the weight range may be based on the statistical variation in the weight of individual items, such as the weight variation of specific vegetables or fruits, etc. For example, a standard weight may be assigned to such items with variable weight, and the weight range takes into account the statistical deviation of individual items from the standard weight.

[0038] The recording of dependencies is an automatic step and does not cause delays in the picking operation.

[0039] A given target container (T) may have multiple dependencies from multiple different source containers (S).

[0040] When the source container (S) is moved to a location to be weighed after the picking operation, the target delivery container (T) is sent to the destination. An example of a destination is a delivery staging area in preparation for final delivery. An example of a delivery staging area is a dedicated space at or near a loading dock where delivery containers are loaded onto delivery trucks. Alternatively, the delivery staging area may be a storage room or a designated section of a storage grid. The target container (T) awaits the results of a weighing operation on one or more source storage containers (S) on which it depends, either while in transit or at the destination (e.g., in a delivery staging area).

[0041] If, when S is finally weighed, the weight is within the expected range (statistically, it is the majority of the time), the "dependency" between T and S is removed and T is "cleared" to continue its delivery path, such as being cleared to be loaded onto a delivery truck. In one embodiment, the target container T may include a barcode, Q-code, or other machine-readable code that allows the delivery person to scan the code of the delivery container to determine that the container has been cleared to be loaded onto the truck. The source storage container (S) is also "cleared" to be returned to the stack, and its new weight is recorded by the control system.

[0042] However, if the weight of S exceeds the expected value (i.e., is outside the expected range), both S and T are marked or "tagged" for manual inspection and corrective repackaging if necessary. In one aspect, the storage container S and / or the target container T can be transported to a dedicated location for inspection. In another aspect, S and / or T can be inspected in their respective staging areas.

[0043] It will be appreciated that the present invention eliminates or at least improves any delay caused by the weighing operation by decoupling the weighing operation from the picking operation and performing the weighing operation at a time or location that has less impact on throughput.

[0044] According to another aspect of the invention, the target container (T) can be weighed as a further control of the picking operation, for example in a delivery buffer. In this respect, the control system can compare the results of the weighing operation of the source container (S) and the target container (T) to confirm that the number of items removed from (S) has actually been placed in (T). This comparison may be important, for example, if the items are of high value and there is a risk of theft or misplacement of items.

[0045] According to one aspect, the present invention comprises:

[0046] A method for weighing storage containers in an automated storage and retrieval system to determine the amount of items in the storage containers, in particular determining the number of items in a source storage container (S) after a picking operation for transferring items from a source storage container (S) to a target container (T) is completed, the automated storage and retrieval system comprising an automated vehicle and a picking station, the automated vehicle being adapted to remove storage containers from a storage stack and to reposition storage containers into a storage stack and to transport the storage containers, the picker at the picking station transferring items from a source storage container (S) to a target container (T), the method comprising the following steps:

[0047] a. transporting the source storage container (S) to the picking station,

[0048] b. transferring a predetermined amount of items from said source storage container (S) to said target container (T),

[0049] c. establishing an estimated weight range for the source storage container after transfer, the estimated weight range being based on the number of items of known weight expected to be transferred to the target container,

[0050] d. Recording the dependency relationship between the source storage container and the target container,

[0051] e. transporting the source storage container to a weighing location,

[0052] f. transporting the target container to the delivery staging area,

[0053] g. weighing the source storage container to obtain the weight of the source storage container and any remaining items in the storage container, the weighing of the source container occurring when removed from the picking operation,

[0054] h. determining whether the weight is within the expected weight range based on the weight of the source storage container and any remaining items in the source storage container, and:

[0055] (a) if the weight is within the expected weight range, removing the dependency between the source storage container and the target container, thereby clearing the source storage container for return to the storage stack and clearing the target container for delivery to the intended destination, or

[0056] (b) If the weight is outside the expected weight range, the source storage container and the destination container are marked for inspection and, if necessary, corrective repackaging. BRIEF DESCRIPTION OF THE DRAWINGS

[0057] The following drawings are attached to facilitate understanding of the present invention. The drawings illustrate embodiments of the present invention which will now be described by way of example only, wherein:

[0058] FIG. 1 is a perspective view of a frame structure of a prior art automatic storage and retrieval system.

[0059] 2 is a perspective view of a prior art container handling vehicle having an internally disposed cavity for carrying storage containers therein.

[0060] 3 is a perspective view of a prior art container handling vehicle having a cantilever for carrying storage containers underneath.

[0061] 4 is a perspective view (from below) of a prior art container handling vehicle having an internally disposed cavity for carrying storage containers therein.

[0062] Figure 5 is a perspective view of a prior art picking station.

[0063] Figure 6 It is a diagram showing steps in an embodiment of the present invention.

[0064] Figure 7 It is a figure which shows the embodiment of this invention. DETAILED DESCRIPTION

[0065] In the following, embodiments of the present invention will be discussed in more detail with reference to the accompanying drawings. It should be understood, however, that the drawings are not intended to limit the present invention to the subject matter depicted in the drawings.

[0066] The present invention includes and is used in conjunction with the automatic storage and retrieval system as described in the background section of the present application. The frame structure 100 of the automatic storage and retrieval system 1 is constructed in a similar manner to the frame structure 100 of the prior art described above in conjunction with Figures 1 to 3. That is, the frame structure 100 includes a series of upright members 102 and includes a first upper track system 108 extending in the X direction and the Y direction.

[0067] The frame structure 100 further comprises storage compartments in the form of storage rows 105 arranged between the components 102 , wherein storage containers 106 are stackable in stacks 107 within the storage rows 105 .

[0068] The frame structure 100 may be of any size. In particular, it will be appreciated that the frame structure may be much wider and / or longer and / or deeper than that disclosed in FIG1. ​​For example, the frame structure 100 may have a horizontal extent of more than 700×700 columns and a storage depth of more than twelve containers.

[0069] Now refer to Figure 6 and Figure 7One embodiment of the present invention for an automatic storage and retrieval system according to the present invention is discussed in more detail.

[0070] In the foregoing description, various aspects of the present invention have been described with reference to exemplary embodiments. For ease of explanation, specific numbers, systems, and configurations are listed to provide a comprehensive understanding of the system and its operating principles. However, this description is not intended to be interpreted as having a limiting meaning. Various modifications and variations of the illustrative embodiments, as well as other embodiments of the system, that are obvious to those skilled in the art to which the disclosed subject matter belongs are considered to fall within the scope of the present invention.

[0071] According to one aspect, the present invention provides a method for weighing storage containers in an automatic storage and retrieval system to determine the quantity of items in the storage containers, in particular to determine the quantity of items in a source storage container (S) after a picking operation to transfer items from a source storage container (S) to a target container (T) is completed.

[0072] According to one embodiment of the method, the control system 500 of the automated storage and retrieval system initiates a delivery sequence in which one or more items are transferred from one or more source storage containers (S) to a target container (T). An example of such a delivery sequence is the fulfillment of a customer order, wherein the items included in the order are transferred to a delivery package. However, it should be understood that such a delivery sequence also includes any other transfer of items from a source container to a target container for other purposes, such as for re-storing or reorganizing the contents of a storage container. For simplicity, the present invention will be described in the context of items being transferred to a delivery package, however one skilled in the art will be able to infer the steps of the present invention for other purposes.

[0073] According to one embodiment of the present invention, a source storage container (S) is transported from a stack 107 to a picking station 406. The source storage container may be transported by an automated vehicle, by a conveyor, through a port, or any combination of the foregoing or by other means. The weight of the source container (S) is a known quantity and is recorded by the control system 500. The weight and number of individual items contained within the source container (S) are also known quantities and are recorded by the control system 500. The control system 500 also records information related to the picking operation 600. The information includes the number of items to be transferred to the target container (T). The control system 500 also records the estimated weight 602 that the source container (S) will have after the picking operation 600 has been completed. The estimated weight 602 may be a single value or a range of weights.

[0074] At the picking station 406, a picker 604 transfers items from a source container (S) to a target container (T). The picker 604 may be a manual picking operator or an automated picking device.

[0075] The control system 500 records the "dependency" between the source container (S) and the target container (T). As used herein, the term "dependency" refers to any form of conceptual, temporary association between a source container (S) and a target container (T). In one aspect, the dependency is a computer-implemented association. Such a dependency may be recorded in a memory or implemented by the control system 500 in a manner known in the art of computerized control systems. It should be understood that items from multiple source containers may be added to a target container (T), resulting in the target container (T) having multiple dependencies. For simplicity, the present invention will be described in conjunction with a single dependency between a single source container and a single target container.

[0076] After the transfer of items is completed, the source container (S) is transported to a weighing location 606 including a weighing device 608. The weighing location 606 can be an area adjacent to the picking station or physically remote from the picking station. For example, the weighing location can be an area adjacent to the picking station, which is designated as an "exit buffer" where the containers are stored awaiting transport back to the stack 107. Alternatively, the weighing location 606 can be a dedicated storage staging area physically remote from the picking station, where the containers are stored awaiting transport back to the stack. Alternatively, the weighing location can be located on an automated transport vehicle including the weighing device 608. In connection with the "exit buffer" or "staging area" weighing location, the weighing device 608 can, for example, be integrated into a section of a conveyor belt, or can be adjacent to a conveyor belt with a pushing device that pushes the container onto the weighing device.

[0077] After the item is transferred, the transfer container (T) is transported to a delivery staging area 610. As used herein, the term "delivery staging area" refers to any designated location where the target container (T) is located while awaiting the results of a weighing operation 612, as described below. Non-limiting examples of a delivery staging area include a dedicated space at or near a loading dock where the delivery container is loaded onto a delivery truck. Alternatively, the delivery staging area may be a storage room or a designated section of a storage grid.

[0078] At the weighing location 606, a weighing operation 612 is performed on the source container (S). The weighing operation is performed at a time removed from the picking operation 600. As used herein, the term "at a time removed from the picking operation" should be understood to refer to the amount of time from the completion of the picking operation to the extent that the source container (S) has been sent from the picker so that a new picking operation can be started. In other words, the amount of time such that the actions and / or decisions of the picker are no longer affected by the weighing of the source container, and a new picking operation can be started without considering the weighing operation. In one aspect, the control system 500 calculates and determines the time of the weighing operation based on information related to the throughput of the storage and retrieval system, and the time is determined based on factors intended to eliminate or improve the reduction in throughput caused by any delays associated with the weighing operation 612. On the other hand, the "time removed from the picking operation" is an inherent result of the weighing location 606 being physically far away from the picking station 600.

[0079] If S is finally weighed in weighing operation 612, the weight is within the expected range (statistically, it is the majority of the time), then the "dependency" between T and S is removed and T is "cleared" to continue its delivery path, such as being cleared to be loaded onto a delivery truck. In one embodiment, the target container T may include a barcode, Q-code, or other machine-readable code 614 that allows the delivery personnel to scan the code of the delivery container to determine that the container has been cleared to be loaded onto the truck. The source storage container (S) is also "cleared" to be returned to the stack, and its new weight is recorded by the control system.

[0080] However, if the weight of S exceeds the expected value (i.e., is outside the expected range), both S and T are marked or "tagged" for manual inspection and corrective repackaging if necessary. In one aspect, the storage container S and / or the target container T can be transported to a dedicated location for inspection. In another aspect, S and / or T can be inspected in their respective staging areas.

[0081] According to another aspect of the invention, the target container (T) can be weighed as a further control of the picking operation, for example in a delivery buffer. In this respect, the control system can compare the results of the weighing operation of the source container (S) and the target container (T) to confirm that the number of items removed from (S) has actually been placed in (T). This comparison may be important, for example, if the items are of high value and there is a risk of theft or misplacement of items.

[0082] According to another aspect, the present invention includes a computer program product comprising instructions which, when executed on a control system 500 for an automatic storage and retrieval system, perform a method for weighing storage containers to determine the quantity of items in the storage containers, in particular to determine the number of items in a source storage container after a picking operation at a picking station is completed, which pick station transfers the items from the source storage container to a target container, for example to a delivery package.

[0083] According to this aspect of the invention, a series of terms are defined as follows:

[0084] definition:

[0085]

[0086]

[0087]

[0088] According to one aspect of the invention, cube-based storage includes a warehouse management system (WMS) 616 that is arranged to communicate with the cube control system 500 to track in which bins stock keeping units (SKUs) are located.

[0089] According to one aspect, the present invention includes the following different functions. They can be run at different locations and at different times and can be implemented by storing data in CCS. The final output is a list of storage bins that needs to be manually checked before being stored in CBS.

[0090]

[0091]

[0092] List of reference numbers

[0093] Prior art (Figures 1 to Figure 5 )

[0094] 1. Automatic storage and retrieval system of the prior art 100 Frame structure

[0095] 102 Vertical members of frame structure

[0096] 104 Storage Grid

[0097] 105 Storage Rows

[0098] 106 Storage Container

[0099] 106' Specific location of storage container

[0100] 107 Stacking

[0101] 108 Track System

[0102] 110 Parallel tracks in the first direction (X)

[0103] 112 Access opening

[0104] 119 First port column

[0105] 120 Second port column

[0106] 201 Container handling vehicle of the prior art

[0107] 201a: body of container transport vehicle 201

[0108] 201b Drive device / wheel arrangement / first wheel set in first direction (X)

[0109] 201c Drive device / wheel arrangement / second wheel set in second direction (Y)

[0110] 301 Prior art cantilever container handling vehicle

[0111] 301a: body of container transport vehicle 301

[0112] 301b Driving device / first wheel set in the first direction (X)

[0113] 301c Driving device in the second direction (Y) / second wheel set

[0114] 304 Clamping equipment

[0115] 401 Container handling vehicle of the prior art

[0116] 401a: body of container transport vehicle 401

[0117] 401b Driving device / first wheel set in the first direction (X)

[0118] 401c Driving device in the second direction (Y) / second wheel set

[0119] 404 Clamping equipment

[0120] 404a Lifting belt

[0121] 404b Clamp

[0122] 404c Guide pin

[0123] 404d Lifting Frame

[0124] 405 Goods in the Workstation

[0125] 406 Picking station or "shipping" workstation

[0126] 500 Control System

[0127] X first direction

[0128] Y Second direction

[0129] Z third direction

[0130] 600 Picking Operations

[0131] 602 Estimated weight

[0132] 604 Picker

[0133] 606 Weighing position

[0134] 608 Weighing Equipment

[0135] 610 Delivery Staging Area

[0136] 612 Weighing Operation

[0137] 614 Machine readable code

[0138] 616 Warehouse management system.

Claims

1. A method for weighing a storage container in an automatic storage and retrieval system to determine the amount of items in the storage container, in particular determining the number of items in the source storage container (S) after a picking operation of transferring items from a source storage container (S) to a target container (T) is completed, the automatic storage and retrieval system comprising an automatic vehicle and a picking station (406), the automatic vehicle being adapted to remove the storage container from a storage stack and to reposition the storage container into the storage stack and to transport the storage container, a picker (604) transferring items from the source storage container (S) to the target container (T) at the picking station, the method comprising the following steps: a. transporting the source storage container (S) to the picking station, b. transferring a predetermined amount of items from said source storage container (S) to said target container (T), c. establishing an estimated weight range for the source storage container after transfer, the estimated weight range being based on the number of items of known weight expected to be transferred to the target container, d. Recording the dependency relationship between the source storage container and the target container, e. transporting the source storage container to a weighing location (606), f. transporting the target container to a delivery staging area (610), g. weighing the source storage container to obtain the weight of the source storage container and any remaining items in the storage container, the weighing of the source container occurring when removed from the picking operation, h. determining whether the weight is within the expected weight range based on the weight of the source storage container and any remaining items in the source storage container, and: (a) if the weight is within the expected weight range, removing the dependency between the source storage container and the target container, thereby clearing the source storage container for return to the storage stack and clearing the target container for delivery to the intended destination, or (b) If the weight is outside the expected weight range, the source storage container and the destination container are marked for inspection and, if necessary, corrective repackaging.

2. The method according to claim 1, wherein: Items from a plurality of said source storage containers (S) are transferred into said target container (T), said target container (T) having dependencies to each of said source storage containers which must be removed before said target container can be cleared for delivery.

3. The method according to one of the preceding claims, wherein: The weighing location is one of the following: a. an area adjacent to the picking station designated as an "exit buffer", b. a staging area physically remote from the picking station, c. Installed on an automatic transport vehicle.

4. The method according to claim 3, wherein: The weighing location (606) is an area adjacent to the picking station that is designated as an exit buffer.

5. The method according to claim 3, wherein: The weighing location is a staging area physically remote from the picking station.

6. The method according to claim 3, wherein: The weighing position is arranged on the automatic transport vehicle.

7. A computer program product for an automatic storage and retrieval system, wherein: The computer program product comprises instructions which, when executed on a computing device of a control system (500) operating the automated storage and retrieval system, direct the execution of the method according to any one of claims 1 to 6.

8. The computer program product according to claim 7, wherein: The instructions include:

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