Article arrangement system and warehouse system of physical distribution system
The item placement system optimizes storage area allocation based on co-occurrence frequencies to reduce transport distances and enhance efficiency in logistics systems by grouping items for simultaneous shipping, addressing inefficiencies in existing systems.
Patent Information
- Application Number
- JP2024082374
- Authority / Receiving Office
- JP · JP
- Patent Type
- Applications
- Current Assignee / Owner
- Filing Date
- 2024-05-21
- Publication Date
- 2025-12-04
AI Technical Summary
Existing logistics systems face inefficiencies in resource consumption due to long transport distances when items stored far apart are shipped simultaneously, despite grouping items with high logistics co-occurrence for reduced retrieval costs.
An item placement system that utilizes a first co-occurrence acquisition unit to group items based on simultaneous shipping frequency, allocates storage areas to maximize second co-occurrence between groups, and assigns storage locations within these areas to optimize simultaneous shipping distances, using a combination of machine learning and optimization algorithms.
This approach significantly reduces transport distances and improves work efficiency by increasing the probability of simultaneous shipping among adjacent items, thereby minimizing resource consumption and preventing device interference.
Smart Images

Figure 2025176323000001_ABST
Abstract
Description
[Technical Field]
[0001] The present invention relates to an item placement system for a logistics system, and a warehouse system using the item placement system. [Background technology]
[0002] Japanese Patent Publication No. 2021-88427 (Patent Document 1) discloses that in a logistics warehouse, a logistics co-occurrence degree relating to the logistics co-occurrence between items is defined, and multiple items whose logistics co-occurrence degree is equal to or greater than a threshold are grouped. In Patent Document 1, locations close to each other are determined as storage locations for the grouped items, and the items are stored in the determined locations. Patent Document 1 claims that it is possible to prevent the consumption of resources (time, energy, etc.) related to movement when retrieving items, i.e., the distance the items must travel. [Prior art documents] [Patent documents]
[0003] [Patent Document 1] Patent Publication No. 2021-88427 Summary of the Invention [Problem to be solved by the invention]
[0004] Logistics co-occurrence is an index related to the frequency with which items x and y are shipped at the same time (item x and item y exist in a shipping unit (one order)). For this reason, in Patent Document 1, when items included in a group are shipped at the same time, the consumption of resources related to movement during retrieval (picking) can be reduced. However, when items included in a different group stored far away from the group are shipped at the same time, there is a concern that the transport distance of the items during retrieval will be long, resulting in increased resource consumption.
[0005] An object of the present disclosure is to improve work efficiency by shortening the transport distance of items when items stored in a storage location are shipped simultaneously. [Means for solving the problem]
[0006] 1) The item placement system of the logistics system of the present disclosure includes a first co-occurrence acquisition unit that acquires, for a plurality of items, a first co-occurrence, which is a parameter indicating how often a first item and a second item included in the plurality of items are shipped simultaneously; a grouping unit that divides the items into a plurality of groups based on the first co-occurrence; a second co-occurrence acquisition unit that acquires, for the plurality of groups, a second co-occurrence, which is a parameter indicating how often an item included in the first group divided by the grouping unit and an item included in the second group are shipped simultaneously, based on the first co-occurrence of each of the plurality of items; a first allocation unit that allocates a storage area to each of the plurality of groups based on the second co-occurrence; and a second allocation unit that allocates, to each of the plurality of items, a storage location within the storage area of the group to which the item belongs.
[0007] According to this configuration, the item placement system of the logistics system includes a first co-occurrence acquisition unit, a grouping unit, a second co-occurrence acquisition unit, a first allocation unit, and a second allocation unit. The first co-occurrence is a parameter indicating how often a first item and a second item are shipped simultaneously. The first co-occurrence acquisition unit acquires the first co-occurrence between all items stored in a storage location. The grouping unit divides each item into a plurality of groups based on the first co-occurrence. The grouping unit divides each item into a plurality of groups so that the first co-occurrence between items included in each group is high.
[0008] The second co-occurrence is a parameter that indicates how often items included in the first group and the second group are shipped at the same time. The second co-occurrence acquisition unit acquires the second co-occurrence between all groups. The first allocation unit allocates storage areas to all groups based on the second co-occurrence. A storage area is an area (region) in which a group is located. The first allocation unit allocates storage areas to each group based on the second co-occurrence. The second allocation unit allocates storage locations within the storage area to items included in the group.
[0009] The second co-occurrence is a parameter that indicates how often items included in two groups (the first group and the second group) are shipped simultaneously. Therefore, by using the second co-occurrence, the first allocating unit can allocate storage areas for each group so that when items included in different groups are shipped simultaneously, the probability that items included in groups in adjacent storage areas will be shipped simultaneously increases. Therefore, when items stored in storage locations are shipped simultaneously, it is possible to shorten the transport distance of the items, thereby improving work efficiency.
[0010] 2) Preferably, the first allocation unit may determine combinations of storage areas and multiple groups so as to maximize the sum of the second co-occurrence degrees between groups of adjacent storage areas, and allocate the storage areas to the multiple groups.
[0011] According to this configuration, the first allocating unit finds a combination of storage areas and groups that maximizes the sum of the second degrees of co-occurrence between groups allocated to adjacent storage areas. Then, the first allocating unit allocates storage areas to groups so that the sum of the second degrees of co-occurrence between groups allocated to adjacent storage areas is maximized. Since storage areas are allocated to groups so that the sum of the second degrees of co-occurrence between groups in adjacent storage areas is maximized, it is possible to allocate storage areas for each group so that when items included in different groups are shipped simultaneously, the probability that items included in groups in adjacent storage areas will be shipped simultaneously increases.
[0012] 3) Preferably, in the above 1 and 2, the second co-occurrence acquisition unit may acquire the average or sum of the first co-occurrence degrees between all the items included in the first group and the second group as the second co-occurrence degree.
[0013] According to this configuration, the second co-occurrence degree is calculated by integrating two groups (first group and second group) and calculating the "average value" or "sum" of the first co-occurrence degrees of all items included in the integrated group (two groups). The "average value" and "sum" of the first co-occurrence degrees of all items are suitable indicators of the frequency with which items included in the two groups (first group and second group) are shipped simultaneously, and the second co-occurrence degree can be suitably obtained.
[0014] 4) Preferably, in the above items 1 to 3, the second allocating unit may allocate a storage location closer to the collection location to an item with a higher shipping frequency.
[0015] According to this configuration, an item with a higher loading frequency is allocated to a storage location closer to the collection location, thereby shortening the transport distance of the item when it is shipped.
[0016] 5) A warehouse system disclosed herein is a warehouse system that uses the item placement system of the logistics system described above in 1 to 4. The warehouse system includes a conveying device that conveys items stored in a storage location to a collection location provided within the warehouse. A plurality of aisles along which the conveying device moves are provided within the warehouse, and storage locations are provided on both sides of the aisles along which the conveying device moves, and the areas where the storage locations provided on both sides of the aisles are located may be defined as storage areas.
[0017] According to this configuration, the warehouse system includes a conveying device that conveys items stored in a storage location to a collection location provided within the warehouse. A plurality of aisles along which the conveying device moves are provided within the warehouse. Storage locations are provided on both sides of the aisle along which the conveying device moves. Storage areas are areas in which the storage locations provided on both sides of the aisle are located. Because the warehouse system uses the item placement systems 1 to 4 above, it is possible to shorten the transport distance of items when simultaneously shipping items from each storage area provided on both sides of the aisle, thereby improving work efficiency.
[0018] 6) A warehouse system of the present disclosure is a warehouse system that uses the item placement system of the logistics system described above in 1 to 4. The warehouse system includes a plurality of collection locations provided within the warehouse, and a plurality of conveying devices that convey items from storage locations to the plurality of collection locations.
[0019] According to this configuration, the warehouse system includes a plurality of conveying devices that convey items from storage locations to each of a plurality of collection locations provided within the warehouse. Because the warehouse system uses the item placement system described in 1 to 4 above, when items belonging to different groups are shipped simultaneously, there is a high probability that items belonging to groups in adjacent storage areas will be shipped simultaneously. This shortens the travel distance of each conveying device, thereby reducing the chances of the conveying devices interfering with each other during their movement and preventing a decline in work efficiency in the warehouse.
[0020] 7) A warehouse system of the present disclosure is a warehouse system that uses the item allocation system of the logistics system described above in 1 to 4. The warehouse system includes a plurality of collection locations provided within the warehouse, and a plurality of conveying devices that transport the items from storage locations to the plurality of collection locations. The item allocation system of the logistics system further includes a frequency acquisition unit that calculates, for each of a plurality of groups divided by the grouping unit, a group shipping frequency, which is the shipping frequency of the group, based on the shipping frequencies of the items included in the group. The first allocation unit allocates storage areas so that groups with group shipping frequencies equal to or greater than a threshold are not adjacent to each other, and allocates storage areas for groups based on a second co-occurrence degree of groups with group shipping frequencies less than the threshold.
[0021] According to this configuration, the warehouse system includes a plurality of conveying devices that convey items from storage locations to each of a plurality of collection locations provided within the warehouse. The warehouse system uses the item placement systems described above in 1 to 4. The frequency acquisition unit of the item placement system calculates a group shipping frequency, which is the shipping frequency of each group divided by the grouping unit, based on the shipping frequencies of the items included in the group. The first allocation unit allocates storage areas so that groups with a group shipping frequency equal to or greater than a threshold are not adjacent to each other. The first allocation unit allocates storage areas to groups with a group shipping frequency less than the threshold based on the second co-occurrence of the groups.
[0022] Groups with a group shipping frequency equal to or greater than the threshold are assigned storage areas that are not adjacent to each other, reducing the chance of interference between the transport devices during shipping of items. Also, groups with a group shipping frequency less than the threshold are assigned storage areas based on the second co-occurrence, increasing the probability that items in groups in adjacent storage areas will be shipped simultaneously when the items in these groups are shipped simultaneously, thereby reducing the travel distance of each transport device. [Effects of the Invention]
[0023] According to the present disclosure, when items stored in a storage location are shipped simultaneously, the transport distance of the items can be shortened and work efficiency can be improved. [Brief explanation of the drawings]
[0024] [Figure 1] 1 is a schematic diagram illustrating an example of the overall configuration of a logistics system according to an embodiment of the present invention. [Figure 2] FIG. 10 is a diagram illustrating an example in which grouped items are stored in adjacent storage locations in a comparative example. [Figure 3] FIG. 2 is a diagram illustrating functional blocks of the item placement system according to the present embodiment. [Figure 4] FIG. 10 is a diagram illustrating an allocation pattern in the present embodiment. [Figure 5] 10 is a diagram illustrating a storage location when a storage area is allocated to a group by a first allocation unit. FIG. [Figure 6] FIG. 1 is a diagram illustrating an example in which the item placement system is applied to storing items between warehouses. [Figure 7] FIG. 10 is a diagram illustrating functional blocks of an item placement system in a first modified example. [Figure 8] 2, this is a diagram illustrating an example in which grouped items are stored in adjacent storage locations in a comparative example. [Figure 9] FIG. 10 is a diagram illustrating functional blocks of an item placement system 100A in a second modification. DETAILED DESCRIPTION OF THE INVENTION
[0025] Hereinafter, embodiments of the present disclosure will be described in detail with reference to the drawings. In the drawings, the same or corresponding parts are designated by the same reference numerals, and description thereof will not be repeated.
[0026] FIG. 1 is a schematic diagram showing an example of the overall configuration of a logistics system 1 according to this embodiment. The logistics system 1 includes a warehouse 10, a control device 200, and a server 300. In this embodiment, the warehouse 10 is an indoor warehouse that stores items 20, and the items 20 are laid flat on the floor. The control device 200 is installed inside a building of the warehouse 10. The control device 200 manages the items 20 and controls the conveying device 13. The server 300 can communicate with the control device 200 via a network NW. The server 300 functions as a host system of the control device 200 and, for example, manages the logistics of multiple warehouses 10. The control device 200 and the server 300 are computers configured with a CPU (Central Processing Unit), memory, etc.
[0027] In the warehouse 10, dashed squares Sq indicate the travel route of the conveying device 13, and the conveying device 13 travels (moves) along the squares Sq. In this embodiment, the items 20 are stored on the floor of the storage space 11. The storage space 11 is partitioned for each item 20, and is partitioned into two rows along the aisle 12 along which the conveying device 13 travels. In this embodiment, the storage space 11 is partitioned into 10 units (10 sections), with 5 sections per row. A plurality of storage spaces 11 partitioned into two rows are installed with the aisle 12 between them. FIG. 1 illustrates an area in which four storage spaces 11 (11a to 11d) are installed with three aisles 12 (12a to 12c) between them. The areas in the storage space 11 partitioned for each item 20 are storage locations for the items 20. The items 20 may be placed on pallets and stored in storage locations (sections), or may be stored in storage boxes or the like provided in the storage location.
[0028] The conveying device 13 conveys items 20 stored in a storage location (storage space 11) to a collection location 14. The conveying device 13 is controlled by a control device 200. The control device 200 specifies items to be picked by the conveying device 13 for each shipping unit. The specified items are also referred to as requested items. The conveying device 13 travels (moves) along the grid Sq and conveys requested items stored in the storage location to the collection location 14. If the shipping unit contains multiple requested items, this transport is repeated. The conveying device 13 may be, for example, an automated guided vehicle (AGV), an autonomous mobile robot (AMR), etc.
[0029] When there are multiple requested items in a shipping unit (one order) (multiple items to be shipped at the same time), the items can be grouped and stored in storage locations close to each other, thereby improving work efficiency at the time of shipping. Figure 2 is a diagram illustrating an example of storing grouped items in storage locations close to each other in a comparative example. In Figure 2, items 20 are stored in all of the storage locations (sections) of storage spaces 11a to 11d, and the symbols A to J represent specific items 20 and the storage locations of those items 20.
[0030] Referring to FIG. 2, storage areas in which grouped items 20 are stored adjacent to one another are set on both sides of aisles 12a to 12c. In FIG. 2, the storage areas are indicated by two-dot chain lines. Storage area a is set on both sides of aisle 12a, is composed of a right-hand row of storage spaces 11a in the illustration and a left-hand row of storage spaces 11b in the illustration, and includes ten storage locations (sections). Storage area b is set on both sides of aisle 12b, is composed of a right-hand row of storage spaces 11b in the illustration and a left-hand row of storage spaces 11c in the illustration, and includes ten storage locations (sections). Storage area c is set on both sides of aisle 12c, is composed of a right-hand row of storage spaces 11c in the illustration and a left-hand row of storage spaces 11c in the illustration, and includes ten storage locations (sections). Storage area a and storage area b are adjacent to each other, and storage area b and storage area c are adjacent to each other. Storage area a and storage area c are not adjacent to each other.
[0031] In Figure 2, items 20 included in a group are surrounded by a dashed line. Group 1 (Gr1) is assigned to storage area a, and items included in Gr1 are stored in the storage location of storage area a. Group 2 (Gr2) is assigned to storage area b, and items included in Gr2 are stored in the storage location of storage area b. Group 3 (Gr3) is assigned to storage area c, and items included in Gr3 are stored in the storage location of storage area c. Items A, B, C, and D are frequently shipped together and are included in Gr1. Items E, F, and G are frequently shipped together and are included in Gr2. Items H, I, and J are frequently shipped together and are included in Gr3.
[0032] When the control device 200 commands items A, C, and D included in Gr1 to be shipped simultaneously (as required items in a shipping unit), the travel distance (number of squares Sq) of the conveying device 13 is 34. The conveying device 13 starts picking from the initial position St, and after picking all the required items, returns to the initial position St. In this case, items A, C, and D are frequently shipped simultaneously and are included in Gr1, so they are stored in a storage location in storage area a, and the travel distance of the conveying device 13 can be shortened.
[0033] When the control device 200 commands items A and C in Gr1 and item H in Gr3 as requested items to be shipped simultaneously (although this is less frequent than commands for items A, C, and D), the travel distance (number of squares Sq) of the conveying device 13 is 50. Item H is in Gr3 and is stored in a storage location in storage area c. Storage area a, where items A and C in Gr1 are stored, is separated from storage area c (not adjacent), and when items 20 in storage area a and storage area c are shipped simultaneously, the travel distance of the conveying device 13 becomes longer.
[0034] In this embodiment, the travel distance of the conveying device 13 can be reduced by allocating storage areas for each group using a parameter representing the frequency with which items are shipped simultaneously between groups.
[0035] 3 is a diagram illustrating the functional blocks of the item placement system 100 in this embodiment. The item placement system 100 is configured by a control device 200 and / or a server 300. This functional block may be configured in either the control device 200 or the server 300, or may be configured by the control device 200 and the server 300 working together.
[0036] 3, the first co-occurrence obtaining unit 110 obtains the first co-occurrence using the shipping data X. The shipping data X is data on items shipped in a predetermined period (for example, 30 days, 90 days, etc.). The shipping data X includes data on items in shipping units (data on a combination of items shipped at the same time).
[0037] The first co-occurrence degree is a parameter indicating the frequency with which a first item (item x) and a second item (item y) are shipped simultaneously. The first co-occurrence degree acquiring unit 110 calculates the first co-occurrence degree using the probability P(x, y) that items x and y are shipped simultaneously, for example, by utilizing pointwise mutual information (PMI). (P(x, y) is also referred to as the co-occurrence probability.)
[0038] The first co-occurrence obtaining unit 110 obtains the probability P(x) that item x will be shipped, the probability P(y) that item y will be shipped, and the co-occurrence probability P(x, y) from the shipping data X, and calculates PMI(x, y) using the following formula 1. PMI(x,y)=log[P(x,y) / (P(x)*P(y))]...(Equation 1) Next, the first co-occurrence obtaining section 110 obtains the total positive self information (PPMI) from the following formula 2. PPMI(x, y)=max(0, PMI(x, y)...(Equation 2)
[0039] The first co-occurrence acquiring unit 110 calculates PPMI(x, y) for all items included in the shipping data X, and stores the PPMI(x, y) between all items in memory as first co-occurrence. First co-occurrence table 110A is an example of data stored in memory, and "*" indicates the value of the first co-occurrence (PPMI(x, y)).
[0040] The first co-occurrence degree may be, for example, the co-occurrence probability P(x, y) instead of PPMI(x, y). Alternatively, the cosine similarity (cos(x, y)) of P(x) and P(y) may be used as the first co-occurrence degree.
[0041] The grouping unit 120 groups (groups) items based on the information on the first co-occurrence (PPMI(x, y)) in the first co-occurrence table 110A. The grouping unit 120 groups items with a high first co-occurrence. In this embodiment, one group includes 10 items, which is the capacity of the storage area, and the number of groups is 3, which is the number of storage areas. The grouping unit 120 groups items with a high first co-occurrence using machine learning clustering. As a result, the grouping unit 120 groups each item 20 so that the first co-occurrence between items included in the group is high (large). Alternatively, an optimization algorithm using simulated annealing or a determination algorithm using a rule-based method may be used. The group table 120A is a result of grouping and is an example of data stored in memory. Note that if there are items that are never shipped together (items with a first co-occurrence of 0 with any other item), these items may be divided into groups (non-co-occurrence groups).
[0042] The second co-occurrence acquiring unit 130 acquires the second co-occurrence from the information in the first co-occurrence table 110A and the group table 120A. The second co-occurrence is a parameter indicating the frequency with which items included in a first group (e.g., Gr1) and a second group (e.g., Gr2) are shipped simultaneously. In this embodiment, the second co-occurrence acquiring unit 130 acquires the average value of the first co-occurrence between the items included in the first group and the second group as the second co-occurrence. For example, Gr1 and Gr2 are integrated, and the average value of the first co-occurrence between all items (items A, B, E, F, etc., a total of 20 items) included in the integrated group (Gr1 and Gr2) is calculated as the second co-occurrence between Gr1 and Gr2. The second co-occurrence acquiring unit acquires the second co-occurrence between all groups. Second co-occurrence table 130A is an example of data stored in memory, and represents a case where the second co-occurrence degree between Gr1 and Gr2 is "0.1", the second co-occurrence degree between Gr1 and Gr3 is "1.2", and the co-occurrence degree between Gr2 and Gr3 is "0.8". Note that second co-occurrence acquiring section 130 may calculate the "sum" of the first co-occurrence degrees between all of the items included in the two combined groups as the second co-occurrence degree, or it may be the "variance" or "best value" between all of the items.
[0043] The first allocation unit 140 allocates storage areas to groups based on the information in the second co-occurrence table 130A. The first allocation unit 140 determines the combination of adjacent storage areas and groups that maximizes the sum of the second co-occurrence degrees, and allocates the storage areas to the groups. FIG. 4 is a diagram illustrating allocation patterns in this embodiment. Similar to FIG. 2, FIG. 4 shows an example in which storage areas a, b, and c are adjacent in this order as storage areas, and items 20 are grouped into three groups (Gr1 to Gr3), but the combinations of storage areas and groups are different.
[0044] 4, allocation pattern 1 is a pattern in which Gr1 is allocated to storage area a, Gr2 is allocated to storage area b, and Gr3 is allocated to storage area c (Gr1-Gr2-Gr3). Pattern 2 is a pattern in which Gr1 is allocated to storage area a, Gr3 is allocated to storage area b, and Gr2 is allocated to storage area c (Gr1-Gr3-Gr2). Pattern 3 is a pattern in which Gr2 is allocated to storage area a, Gr1 is allocated to storage area b, and Gr3 is allocated to storage area c (Gr2-Gr1-Gr3).
[0045] According to the second co-occurrence degrees in the second co-occurrence degree table 130A (see FIG. 3), the sum of the second co-occurrence degrees in pattern 1 is 0.9, the sum of the second co-occurrence degrees in pattern 2 is 2.0, and the sum of the second co-occurrence degrees in pattern 3 is 1.3. The first allocation unit 140 determines the combination of adjacent storage areas and groups so as to maximize the sum of the second co-occurrence degrees, and allocates storage areas a to c to groups (Gr1 to Gr3), so in this embodiment, an allocation pattern of pattern 2 is set. (Note that in this embodiment, since there is symmetry in the arrangement of storage areas a to c, pattern 1 (Gr1-Gr2-Gr3) is the same as pattern 4 (Gr3-Gr2-Gr1), and pattern 4 is not considered.)
[0046] The second allocation unit 150 allocates storage locations within the storage area to the items 20 included in each group. The second allocation unit 150 extracts the items included in the group by referring to the group table 120A. Then, for example, the storage location is allocated so that the higher the probability (shipping frequency) of an item being shipped, the closer the item is to be stored in a storage location (section) closer to the collection location 14. For example, if item A included in Gr1 has a higher shipping frequency than item C, item A is allocated a storage location closer to the collection location 14 than item C. In this embodiment, the shorter the travel distance of the conveying device 13 from the initial position St to the storage location, the closer the storage location is to be allocated to the collection location 14.
[0047] FIG. 5 is a diagram illustrating storage locations when storage areas are assigned to groups by the first assignment unit 140. As described above, the first assignment unit 140 sets an assignment of pattern 2 that maximizes the sum of the second co-occurrence degrees. In pattern 2, as shown in FIG. 5, Gr1 is assigned to storage area a, Gr3 is assigned to storage area b, and Gr2 is assigned to storage area c. When storage areas are assigned to each group in this manner, when the control device 200 commands items A, C, and D included in Gr1 to be shipped simultaneously, the travel distance (number of squares Sq) of the conveying device 13 is 34, as in the case of FIG. 2. When the control device 200 commands items A, C, and H included in Gr1 to be shipped simultaneously, the travel distance (number of squares Sq) of the conveying device 13 is 44, which is shorter than the case of FIG. 2.
[0048] The first allocating unit 140 determines the combination of adjacent storage areas and groups so as to maximize the sum of the second co-occurrence degrees, and allocates storage areas a to c to the groups, so that the frequency with which items included in groups allocated to adjacent storage areas are shipped simultaneously increases compared to the allocation of storage areas in Fig. 2. This makes it possible to shorten the travel distance of the conveying device 13.
[0049] The second allocation unit 150 allocates an item within a group to a storage location closer to the collection location 14, the higher the shipping frequency of the items A to D included in Gr1 in FIG. 5, for example, the shipping frequency is "A>D>B>C", and the higher the shipping frequency, the closer the item is allocated to a storage location (section) closer to the collection location 14. The higher the shipping frequency, the closer the item is stored to the collection location 14, so it is possible to shorten the travel distance of the conveying device 13 during picking.
[0050] The items 20 may be stored (entered) into the storage location (section) using the conveying device 13, or may be entered using a conveying device for warehousing (not shown). Alternatively, a worker may enter (store) the items 20 into the storage location using an instruction sheet output from the item placement system 100, an electronic kanban, or the like. The warehouse 10 equipped with the conveying device 13, the control device 200, and the like corresponds to an example of the "warehouse system" of the present disclosure.
[0051] In the above embodiment, the item location system 100 of the logistics system 1 has been described as being applied to the storage of items in the warehouse 10. However, the item location system 100 can also be applied to cases where items are collected from multiple warehouses at a collection center. FIG. 6 is a diagram illustrating an example in which the item location system 100 is applied to the storage of items between warehouses. Referring to FIG. 6, a truck 510 collects items stored in multiple warehouses A to D and sends them to a collection center 500. In this example, the warehouses correspond to storage areas, with warehouse A set as storage area a, warehouse B set as storage area b, warehouse C set as storage area c, and warehouse D set as storage area d. Each of warehouses A to D is equipped with a control device 200 capable of communicating with the server 300 via a network NW, and constitutes the item location system 100.
[0052] As in the above embodiment, the item placement system 100 calculates the first co-occurrence between items from the shipping data X and groups the items based on the first co-occurrence. In the example of FIG. 6, there are four storage areas (warehouses), so the items are grouped into four groups (Gr1 to Gr4). Then, the second co-occurrence between the groups is calculated, and a combination of adjacent warehouses A to D (storage areas a to d) and groups is determined so as to maximize the sum of the second co-occurrence, and the storage areas a to d (warehouses A to D) are assigned to the groups (Gr1 to Gr4). Furthermore, the item placement system 100 assigns storage locations for items included in a group that are closer to the exits of each of the warehouses A to D the higher the shipping frequency.
[0053] According to this example, the combination of adjacent storage areas (warehouses A to D) and groups is determined so as to maximize the sum of the second co-occurrence degrees, and the storage areas (warehouses A to D) are assigned to the groups, so that items included in groups assigned to adjacent storage areas (warehouses A to D) are shipped simultaneously more frequently, which makes it possible to shorten the travel distance of truck 510.
[0054] (Variation 1) FIG. 7 is a diagram illustrating a warehouse 10A in a first modified example. The warehouse 10A in the first modified example further includes collection locations 14a and 14b, and conveying devices 13a and 13b in the warehouse 10 in the above embodiment. The warehouse 10A includes a plurality of collection locations 14, 14a, and 14b, and a plurality of conveying devices 13, 13a, and 13b. The conveying device 13 conveys stored items to the collection location 14. The conveying device 13a conveys stored items to the collection location 14a. The conveying device 13b conveys stored items to the collection location 14b. The storage location of each item is set by the item placement system 100 in the same manner as in the above embodiment.
[0055] In Modification 1, as in the above embodiment, the first allocation unit 140 determines the combination of adjacent storage areas and groups so as to maximize the sum of the second co-occurrence degrees, and allocates storage areas a to c to the groups. This increases the frequency with which items included in groups allocated to adjacent storage areas are shipped simultaneously, making it possible to shorten the travel distances of conveying devices 13, 13a, and 13b. This makes it possible to prevent backlogs on conveying devices when multiple conveying devices are used for shipping.
[0056] For example, assume that items A, C, and H are instructed to conveying device 13 as requested items to be shipped simultaneously (as requested items in a shipping unit), items H and I are instructed to conveying device 13a, and items G and E are instructed to conveying device 13b. Note that items H and I are grouped by the first co-occurrence degree so that items H and I are shipped simultaneously more frequently, and items G and E are shipped simultaneously more frequently.
[0057] Fig. 8 is a diagram illustrating an example of storing grouped items in a nearby storage location in a comparative example, similar to Fig. 2. In this case, as shown in Fig. 8, the travel paths of conveying device 13 and conveying devices 13a and 13b overlap (interfere), so there is a possibility that conveying devices 13a and 13b may become stuck on their travel paths, which may reduce work efficiency.
[0058] In contrast, in Modification 1, as shown in Fig. 7, the items picked by conveying device 13 are assigned to adjacent storage areas, so the warehouse routes of conveying device 13 and conveying device 13b do not overlap (interfere). This makes it possible to prevent conveying device 13b from being congested, and to prevent a decrease in work efficiency. Note that in Modification 1, some or all of Warehouses A to D may be used as storage areas for items or products in a factory or the like.
[0059] (Variation 2) 9 is a diagram illustrating the functional blocks of an item placement system 100A in Modification 2. The item placement system 100A in Modification 2 includes a frequency calculation unit 160 in addition to the functions of the item placement system 100 in the above embodiment. The functions of the first co-occurrence acquisition unit 110, the grouping unit 120, and the second assignment unit 150 are substantially the same as those in the above embodiment.
[0060] The frequency calculation unit 160 calculates the shipping frequency of the groups grouped by the grouping unit 120. For example, it extracts items included in the group by referring to the group table 120A (see FIG. 3). The frequency calculation unit 160 calculates the sum ΣP of the shipping probabilities (shipping frequencies) of all items included in the group, and sets the sum ΣP as the shipping frequency of the group. Then, it identifies a group whose sum ΣP is equal to or greater than a threshold α. Alternatively, the frequency calculation unit 160 may calculate the average Pave of the shipping probabilities (shipping frequencies) of all items included in the group, set the average Pave as the shipping frequency of the group, and identify a group whose average Pave is equal to or greater than a threshold β. Furthermore, it may be possible to determine the threshold α so that, for example, two or more groups can be identified that are ranked higher than the group with the highest sum ΣP.
[0061] The second co-occurrence obtaining section 130 obtains the second co-occurrence between groups for groups not identified by the frequency calculation section 160 (groups for which the sum ΣP is less than the threshold value α), in the same manner as in the above embodiment. Note that the second co-occurrence obtaining section 130 does not necessarily need to obtain information on groups not identified from the frequency calculation section 160. In that case, it is sufficient to obtain the second co-occurrence between all groups.
[0062] The first allocating unit 140 allocates storage areas to groups identified by the frequency calculating unit 160 (groups whose sum ΣP is equal to or greater than the threshold value α) so that the groups are not adjacent to each other. Furthermore, for groups for which the second co-occurrence degree has been acquired, the first allocating unit 140 determines a combination of adjacent storage areas and groups so that the sum of the second co-occurrence degrees is maximized, and allocates storage areas to the groups, in the same way as in the above embodiment.
[0063] The item placement system 100A of the second modification is applied to a warehouse equipped with multiple conveying devices, such as the warehouse 10A of the first modification. It is particularly suitable for a warehouse with five or more storage areas. In the second modification, groups whose items are frequently shipped together are assigned to distant storage areas. Therefore, in a warehouse equipped with multiple conveying devices, it is possible to prevent overlapping of the travel paths of the conveying devices, prevent the conveying devices from stagnating, and prevent a decrease in work efficiency. Furthermore, for groups whose items are relatively infrequently shipped together, a combination of adjacent storage areas and groups is determined so as to maximize the sum of the second co-occurrence degrees, and a storage area is assigned to the group, thereby making it possible to shorten the travel distance of the conveying devices.
[0064] In the above embodiment, the warehouse is a warehouse where items are laid out flat. However, it may be an automated warehouse with multiple shelves arranged vertically (up and down), and the conveying device may be a stacker crane or the like. In this case, the second allocating unit 150 may allocate items with a higher shipping frequency to a storage location that requires a shorter transport time to the collection location.
[0065] In the above embodiment, a warehouse was used as an example, but the storage location of items determined by the item placement system 100 may also be applied to the placement of containers at ports, the placement of items and products (inventory) within factories, etc.
[0066] In the above embodiment, an example of picking using the conveying device 13 has been described, but it may be picking by a worker, joint picking by a worker and a conveying device (robot), picking using a forklift, etc. Also, an example of conveying device 13 conveying one item at a time has been described, but it may also be applied to a conveying device that can convey multiple items at a time.
[0067] In the above embodiment, the case where the number of storage areas is 3 to 5 has been described, but the number of storage areas may be any number equal to or greater than 3. Note that items for which a storage location is specified due to the characteristics of the items 20 do not need to be grouped by the grouping unit. For example, for items that require refrigeration, the storage location may be determined so that the items are stored in a storage area (warehouse) equipped with refrigeration equipment, and the items may be excluded from the storage area allocation targets of the present disclosure.
[0068] The item allocation system 100, 100A may set the allocation of storage locations for items periodically, for example, quarterly. Alternatively, the allocation of storage locations may be set each time a model change of the target item occurs. Once the second allocation unit 150 has received shipping frequency information from the shipping data X and grouping information from the grouping unit 120, it may determine the item allocation within the storage area without waiting for processing by the second co-occurrence acquisition unit 130 or the first allocation unit 140.
[0069] The embodiments disclosed herein should be considered to be illustrative in all respects and not restrictive. The scope of the present invention is defined by the claims, not by the description of the above embodiments, and is intended to include all modifications within the meaning and scope of the claims. [Explanation of symbols]
[0070] 1 Logistics system, 10, 10A warehouse, 11 storage space, 12 aisle, 13 conveying device, 14 storage location, 20 goods, 100, 100A goods placement system, 110 first co-occurrence acquisition unit, 120 grouping unit, 130 second co-occurrence acquisition unit, 140 first allocation unit, 150 second allocation unit, 160 frequency calculation unit, 200 control device, 300 server, 500 collection center, 410 truck.
Claims
1. a first co-occurrence degree acquiring unit that acquires a first co-occurrence degree, which is a parameter indicating a frequency with which a first item and a second item included in the plurality of items are shipped simultaneously; a grouping unit that divides the plurality of articles into a plurality of groups based on the first co-occurrence degree; a second co-occurrence degree acquiring unit that acquires, for the plurality of groups, a second co-occurrence degree, which is a parameter indicating a frequency with which an item included in a first group and an item included in a second group, which are divided by the grouping unit, are shipped simultaneously, based on the first co-occurrence degree of each of the plurality of items; a first allocation unit that allocates a storage area to each of the plurality of groups based on the second co-occurrence degree; and a second allocation unit that allocates, to each of the plurality of items, a storage location within the storage area of the group to which the item belongs.
2. 2. The item placement system of claim 1, wherein the first allocation unit determines combinations of the storage areas and the plurality of groups so as to maximize the sum of the second co-occurrence degrees between groups of adjacent storage areas, and allocates the storage areas to the plurality of groups.
3. 3. The item placement system of a logistics system according to claim 1, wherein the second co-occurrence acquisition unit acquires the average or sum of the first co-occurrences between all items included in the first group and the second group as the second co-occurrence.
4. 3. The item allocation system for a physical distribution system according to claim 1, wherein the second allocation unit allocates the storage location closer to a collection location to an item with a higher shipping frequency.
5. A warehouse system using the item placement system for a logistics system according to claim 1 or 2, a conveying device that conveys the items stored in the storage location to a collection location provided within the warehouse; A plurality of passages along which the conveying device moves are provided in the warehouse, the storage locations are provided on both sides of the passage along which the conveying device moves, A warehouse system in which the storage area is an area in which the storage locations provided on both sides of the aisle along which the conveying device moves are located.
6. A warehouse system using the item placement system for a logistics system according to claim 1 or 2, Multiple collection points set up within the warehouse, and a plurality of conveying devices that convey items from the storage location to the plurality of collection locations.
7. A warehouse system using the item placement system for a logistics system according to claim 1, Multiple collection points set up within the warehouse, a plurality of conveying devices that convey items from the storage location to the plurality of collection locations; The item placement system includes: a frequency acquisition unit that calculates a group shipping frequency, which is the shipping frequency of each of the plurality of groups divided by the grouping unit, based on the shipping frequencies of the items included in the group; The first allocation unit allocates the storage areas so that groups whose group shipping frequency is equal to or greater than a threshold are not adjacent to each other, and allocates the storage areas for groups whose group shipping frequency is less than the threshold based on the second co-occurrence degree of the groups.
Citation Information
Patent Citations
Physical distribution warehouse system and its method
JP2021088427A