Product transportation plan change device, program, and product transportation plan change method

Abstract

The product transportation plan change device (13) includes an input unit (13a) that receives input values including an initial product transportation plan and a product shipping plan and operation information including information on each facility; a destination change unit (13e) that, when it is determined that there is a destination that does not satisfy the constraints using the upper limit of product acceptance volume at each destination and the available time for warehousing work calculated based on the input values and the operation information, changes the destination that does not satisfy the constraints to another warehouse building for transportation work selected according to a predetermined first priority; and an allocation change unit (13g) that changes a transportation vehicle with a high transportation workload to another transportation vehicle when an evaluation value indicating the variation in workload among transportation vehicles exceeds an allowable upper limit.

Description

[Technical Field]

[0001] The present disclosure relates to a product transportation plan changing device, a program, and a product transportation plan changing method, and more particularly to a product transportation plan changing device, a program, and a product transportation plan changing method for a transport vehicle that transports products manufactured in a factory to a warehouse building. [Background technology]

[0002] Generally, in the manufacturing industry, products manufactured in factories are first stored in the factory's product yard. The products are then loaded onto transport vehicles and brought into the warehouse building. Once brought into the warehouse building, the products are stored there until they are shipped. Overhead cranes are often installed in the product yard and warehouse building to handle the loading and unloading of products.

[0003] When transporting products from a factory's product yard to a warehouse building, the products are loaded onto a transport vehicle. Most transport vehicles used for product transportation are designed to store a dolly carrying the product inside the vehicle. This allows the towing unit to move to perform other transportation tasks while the product is being loaded and unloaded in the product yard or warehouse building. There are also several types of dollies depending on the specifications of the product to be loaded.

[0004] In many cases, a specific type of trolley is used for each product yard in a factory where products are transported. Assigning one transport vehicle to transport products in one product yard reduces the likelihood of uneven distribution of trolley types, simplifies the transport vehicle's travel route, and results in a more efficient transportation plan. However, the number of product yards in a factory from which products are transported generally exceeds the number of transport vehicles used to transport the products. Therefore, it becomes necessary to assign one transport vehicle to transport products in multiple product yards. Depending on how the transport vehicles and product yards are combined in the product transportation plan, uneven distribution of the transport vehicle workloads can occur. Uneven distribution of the transport vehicle workloads can delay the completion time of vehicles with heavy workloads, adversely affecting the overall work efficiency of the transport vehicles. A decrease in the overall work efficiency of the transport vehicles can delay the transport of products from the product yard within the factory to the warehouse building. If the storage capacity of the factory's product yard reaches its upper limit and no more space is available, a product yard congestion occurs, resulting in a lack of storage space for manufactured products. As a result, the factory's production line must be stopped, which increases production costs or opportunity losses. Furthermore, interruptions to temperature control or continuous processes can have a negative impact on product quality. For this reason, factory production line stoppages due to product yard blockages must be avoided as much as possible. Therefore, in actual operations, in order to eliminate workload imbalances, transport vehicles with lighter workloads may be instructed to perform some of the work of transport vehicles with heavier workloads.

[0005] In recent years, algorithms have been proposed that allow computers to execute manual plan changes instead of manual processes to reduce the burden of manual work. For example, Patent Document 1 discloses a system that automatically learns and sets evaluation parameters for evaluating product transportation plans. Furthermore, Patent Document 2 discloses a system that takes into account qualitative constraints on vehicle allocation, which are the user's know-how, and supports the generation of more efficient product transportation plans. [Prior art documents] [Patent documents]

[0006] [Patent Document 1] Japanese Patent Application Laid-Open No. 2013-014387 [Patent Document 2] Japanese Patent Application Publication No. 2018-020897 Summary of the Invention [Problem to be solved by the invention]

[0007] To optimize product transportation plans, it is necessary to eliminate the workload imbalances of transport vehicles, as described above. Furthermore, when determining the destination warehouse for a product, it is necessary to calculate the overhead crane's outbound operation time at each warehouse and estimate the available time for inbound operations from that value. Furthermore, if a warehouse is overwhelmed with product storage, the warehouse may be unable to accept the product even if a transport vehicle delivers it to that warehouse. In other words, when determining the destination warehouse for a product, it is necessary to consider the maximum product acceptance volume at each warehouse. Thus, optimizing product transportation plans requires calculating the workload of each transport vehicle based on the initial plan and calculating the inbound operation capacity constraints at each destination warehouse. While each plan information changes constantly in response to operational fluctuations, changes to product transportation plans are often made manually.

[0008] Furthermore, even if the change process is automated, the systems of Patent Documents 1 and 2 have the following problems. The system of Patent Document 1 calculates an evaluation value for an automatically created product transportation plan, and resets weighting coefficients so that the evaluation value becomes the evaluation target value when manual corrections and the estimated value of the manually corrected plan are input as evaluation target values. However, the system of Patent Document 1 requires manual execution of the plan change process, making it impossible to eliminate personal factors from the plan change process. The system of Patent Document 2 inputs information about the plan change content, which is the user's know-how, and performs plan revisions probabilistically based on the frequency of qualitative corrections in the history of previously generated plans. However, the system of Patent Document 2 is unable to quantitatively evaluate the workload at each logistics facility in real time.

[0009] In consideration of these circumstances, the purpose of the present disclosure is to provide a product transportation plan change device, program, and product transportation plan change method that can automatically equalize the workload at the destination and the workload of the transport vehicle. [Means for solving the problem]

[0010] (1) A product transportation plan change device according to an embodiment of the present disclosure includes: A product transportation plan change device that changes an initial product transportation plan for a transportation vehicle from a transportation source to a transportation destination in a target time period for optimization, an input unit that receives input values including the initial product transportation plan and the product shipping plan and operation information including information on each facility; a destination change unit that, when determining that there is a destination that does not satisfy the constraints using the upper limit of product acceptance volume at each destination and the available time for warehousing work calculated based on the input values and the operation information, changes the destination that does not satisfy the constraints to another warehouse building for transportation work selected according to a predetermined first priority; and an allocation change unit that changes a delivery vehicle with a high delivery workload to another delivery vehicle when an evaluation value indicating a variation in workload among the delivery vehicles exceeds an allowable upper limit value.

[0011] (2) As one embodiment of the present disclosure, in (1), The system includes an integration unit that creates an integrated plan based on the initial product transportation plan and additional transportation work that is added at the time of execution of the change process.

[0012] (3) As one embodiment of the present disclosure, in (2), The predetermined first priority includes lowering the priority of transportation work that requires urgent transportation, lowering the priority of transportation work in descending order of the value of the product transportation work completion time for each transportation source, lowering the priority of transportation work for which the linking of the product number of the product to be transported has not been completed, and lowering the priority of the additional transportation work.

[0013] (4) As an embodiment of the present disclosure, in (2) or (3), The integration unit integrates the initial product transportation plan and the additional transportation work, and then the destination change unit performs a process to change the destination warehouse building and the allocation change unit performs a process to change the assigned transportation vehicle, and an output unit outputs an integrated product transportation plan in which the transportation order has been adjusted according to a predetermined second priority.

[0014] (5) As an embodiment of the present disclosure, in (4), The predetermined second priority includes increasing the priority in ascending order of the start time of the work time slot for each transportation task, decreasing the priority of transportation tasks for which the assigned transportation vehicle has been changed, decreasing the priority of the additional transportation tasks, and increasing the priority in ascending order of the transportation order originally set in the initial product transportation plan and the additional transportation tasks.

[0015] (6) As an embodiment of the present disclosure, in any one of (1) to (5), The evaluation value is the standard deviation of the values indicating the transportation workload.

[0016] (7) A program according to an embodiment of the present disclosure includes: a product transportation plan modification device that modifies an initial product transportation plan by a transportation vehicle from a transportation source to a transportation destination during a target time period for optimization; receiving input values including the initial product transportation plan and product shipping plan and operation information including information on each facility; When it is determined that there is a destination that does not satisfy the constraints using the upper limit of product acceptance volume at each destination and the available time for warehousing work calculated based on the input values and the operation information, for transportation work selected according to a predetermined first priority, change the destination that does not satisfy the constraints to another warehouse building; If the evaluation value indicating the variation in workload among the transport vehicles exceeds an allowable upper limit, the transport vehicle with a high transport workload is changed to another transport vehicle.

[0017] (8) A method for changing a product transportation plan according to an embodiment of the present disclosure includes: A method for changing a product transportation plan for optimizing an initial product transportation plan by a transportation vehicle from a transportation source to a transportation destination during a target time period, comprising: receiving input values including the initial product transportation plan and product shipping plan and operation information including information on each facility; When it is determined that there is a destination that does not satisfy the constraints using the upper limit of product acceptance volume at each destination and the available time for warehousing work calculated based on the input values and the operation information, for transportation work selected according to a predetermined first priority, change the destination that does not satisfy the constraints to another warehouse building; When the evaluation value indicating the variation in workload among the transport vehicles exceeds an allowable upper limit, the transport vehicle with a high transport workload is changed to another transport vehicle. [Effects of the Invention]

[0018] According to the present disclosure, it is possible to provide a product transportation plan modification device, program, and product transportation plan modification method that can automatically equalize the workload at the destination and the workload of the transportation vehicle. [Brief explanation of the drawings]

[0019] [Figure 1] FIG. 1 is a schematic diagram showing a logistics system including a product yard, a warehouse building, and transport vehicles. [Figure 2] FIG. 2 is a schematic diagram illustrating the input / output configuration of a product transportation plan change device according to an embodiment of the present disclosure. [Figure 3] FIG. 3 is a block diagram showing the configuration of a product transportation plan change device. [Figure 4] FIG. 4 is a diagram showing an example of an initial product transportation plan. [Figure 5] FIG. 5 is a diagram illustrating an example of an additional transportation operation. [Figure 6] FIG. 6 is a diagram illustrating an example of a product shipping plan. [Figure 7] FIG. 7 is a diagram illustrating an example of product inventory. [Figure 8] FIG. 8 is a diagram illustrating an example of transport vehicle travel time information. [Figure 9] FIG. 9 is a diagram illustrating an example of destination priority information. [Figure 10] FIG. 10 is a diagram showing an example of each piece of facility information. [Figure 11] FIG. 11 is a diagram showing an example of a plan in which additional transportation work is integrated into the initial product transportation plan. [Figure 12] FIG. 12 is a diagram showing an example of a plan in which the process of changing the destination warehouse building is performed on the plan of FIG. [Figure 13] FIG. 13 is a diagram showing an example of a plan in which the process of changing the assigned transport vehicles has been performed on the plan of FIG. [Figure 14] FIG. 14 is a flowchart showing the process of the product transportation plan change method. [Figure 15] FIG. 15 is a diagram showing the results of comparing the ratio of the transportation task completion time to the target time length in the examples. [Figure 16] FIG. 16 is a diagram showing the results of comparing the transportation task completion times in the examples. DETAILED DESCRIPTION OF THE INVENTION

[0020] Hereinafter, a product transportation plan change device 13 (see FIG. 2), a program, and a product transportation plan change method according to an embodiment of the present disclosure will be described with reference to the drawings.

[0021] FIG. 1 is a schematic diagram showing a logistics system including a product yard, warehouse building, and transport vehicles, which are targets of a product transportation plan that is changed by a product transportation plan change device 13 according to this embodiment. Changing the product transportation plan refers to a change for optimization. Here, the source and destination of transportation targeted by the product transportation plan change device 13 are not limited to specific locations, but this embodiment will be described using the product yard and warehouse building in the logistics system of FIG. 1 as an example. In FIG. 1, reference numeral 1 denotes a factory, reference numerals 1a to 1d denote factory buildings, reference numeral 2 denotes a warehouse, and reference numerals 2a to 2c denote warehouse buildings (warehouse buildings). Reference numerals 3a to 3d and 4a to 4c denote overhead cranes, reference numerals 5a and 5b denote transport vehicles, reference numerals 6a to 6c denote product transport carts, reference numeral 7 denotes a loading crane, and reference numeral 8 denotes a transport ship.

[0022] The factory and warehouse are made up of buildings (1a-1d and 2a-2c) for storing products. The factory buildings (1a-1d) are also called "product yards." Each building is equipped with overhead cranes (3a-3d and 4a-4c) for storing and retrieving products. Products produced in the factory are loaded onto carts (6a and 6b), which are then loaded onto a transport vehicle (5a) and transported to the destination warehouse building. As the shipping date approaches, the stored products are either loaded into the temporary shipping storage area (2d) by the overhead crane, or loaded onto a transport vehicle (5b) with the cart (6c) and moved to a quay near the loading crane (7) and loaded onto a transport ship (8).

[0023] FIG. 2 is a schematic diagram showing the configuration of a product transportation plan modification device 13 according to this embodiment. The arrows in FIG. 2 and FIG. 3, which will be described later, simply indicate the flow of data input / output and processing. As shown in FIG. 2, the product transportation plan modification device 13 acquires an initial product transportation plan 9, a product shipment plan 11, and a warehouse inventory amount 12 as input values, and executes processing of a product transportation plan modification method (e.g., processing such as reassigning to a more appropriate transportation vehicle). Here, the input values may further include an additional transportation task 10. Details of the additional transportation task 10 will be described later. The initial product transportation plan 9 is a plan for initial product transportation to which transportation vehicles are provisionally assigned, and a specific example will be described later. The product shipment plan 11 is a plan for shipment from a warehouse to a transport ship or the like, and a specific example will be described later. The warehouse inventory amount 12 is the amount of product inventory in a warehouse building, and a specific example will be described later.

[0024] Here, the product transportation plan modification device 13 performs processing by referring to the operation database 14. The product transportation plan modification device 13 calculates the workload at the destination and the workload of the transportation vehicle, performs processing such as reassigning the work to a more appropriate transportation vehicle so as to automatically equalize these workloads, and outputs the modified plan. Here, when an additional transportation task 10 occurs and is included as an input value, the product transportation plan modification device 13 integrates the additional transportation task 10, optimizes the plan, and outputs it. Therefore, the modified plan generated by the product transportation plan modification device 13 performing processing is called an integrated product transportation plan 15.

[0025] Product transportation plan modification device 13 is configured with an information processing device and modifies the product transportation plan for a time period specified by a user (hereinafter referred to as the "target time period"). FIG. 3 is a block diagram showing the configuration of product transportation plan modification device 13. As shown in FIG. 3, product transportation plan modification device 13 functions as each component when an arithmetic processing device (processor) inside the information processing device (computer) reads and executes a computer program. In other words, the program causes the arithmetic processing device to function as input unit 13a, integration unit 13b, constraint condition derivation unit 13c, workload calculation unit 13d, delivery destination change unit 13e, load leveling calculation unit 13f, allocation change unit 13g, delivery order adjustment unit 13h, and output unit 13i. The functions of each of these units will be described later.

[0026] The product transportation plan change device 13 may constitute a product transportation plan change system together with devices connected via a network. The network may be, for example, the Internet. The network may also be configured to include, for example, a local area network (LAN) in part.

[0027] The product transportation plan modification system may be configured to include a terminal device used by an operator operating the product transportation plan modification device 13 or an operator of a transportation vehicle to confirm a plan or command for product transportation. The terminal device has at least a function of informing the operator of the modified product transportation plan output from the product transportation plan modification device 13. The terminal device may be, but is not limited to, a general-purpose mobile terminal such as a general-purpose personal computer, smartphone, or tablet. Here, the terminal device has a communication function and can obtain information regarding the modified product transportation plan from the product transportation plan modification device 13 via a network.

[0028] The initial product transportation plan 9 describes the planned product transportation to be carried out during a certain scheduled work time period, and stores information such as the product yard from which the product will be transported, the warehouse building to which the product will be transported, and the type of cart. As mentioned above, transportation vehicles are provisionally assigned to the initial product transportation plan 9. Figure 4 shows an example of the initial product transportation plan 9. The meaning of each item in the initial product transportation plan 9 shown in Figure 4 is as follows:

[0029] The work time period (start time) is the scheduled start time of the product transport. The work time period (end time) is the scheduled end time of the product transport. The product yard (source) is the name of the product yard from which the product transport is to be carried out. The warehouse building (destination) is the name of the warehouse building to which the product transport is to be carried out. The transport vehicle model is the model of the transport vehicle that will transport the product. The trolley type is the type of trolley used to transport the product. The assigned transport vehicle is the transport vehicle assigned to the product transport, and each transport vehicle is indicated by a unique identification code. The number of products is the number of products that can be carried in the product transport. The urgent flag is a flag attached to work that requires immediate transport to the destination in the product transportation plan. The confirmed flag is a flag attached to work in the product transportation plan where the linking of the transport work and the product part number to be transported has been completed. The urgent flag and confirmed flag are applicable if they are "TRUE" and not applicable if they are "FALSE". For example, a work with an urgent flag of "TRUE" indicates that it requires immediate transport to the destination. Furthermore, for example, an operation in which the confirmation flag is "FALSE" indicates that the linking of the product number of the product to be transported has not been completed.

[0030] The additional transportation work 10 is transportation work that is added to a product transportation plan to be carried out during a certain scheduled work time slot at the time the product transportation plan modification device 13 executes its processing. While the initial product transportation plan 9 is a collection of transportation work that was already set as a plan at the time the product transportation plan modification device 13 executes its processing, the additional transportation work 10 is a collection of transportation work that has been added due to the occurrence of a plan change or other reason. Here, since the additional transportation work 10 is transportation work that occurred after the initial product transportation plan 9 was generated, it may include work that requires transportation to an urgent destination. Figure 5 shows an example of the additional transportation work 10. The meaning of each item of the additional transportation work 10 shown in Figure 5 is the same as in Figure 4.

[0031] The product shipping plan 11 records the number of products scheduled to be shipped from the warehouse building to the shipping quay during a certain scheduled work time period. Figure 6 shows an example of the product shipping plan 11. The meaning of each item in the product shipping plan 11 shown in Figure 6 is as follows:

[0032] The work time period (start time) is the start time of the work time period during which shipping work is carried out in the warehouse building. The work time period (end time) is the end time of the work time period during which shipping work is carried out in the warehouse building. The warehouse building is the name of the warehouse building where shipping work is carried out. The warehouse building name is indicated by an identification code unique to each warehouse building. The number of products shipped is the number of products that the warehouse building will ship during its work time period.

[0033] Warehouse inventory quantity 12 is the inventory quantity of products in a warehouse building. In each warehouse building, inventory quantity is measured using a known method. The inventory quantity of warehouse inventory quantity 12 fluctuates to reflect changes in the actual measured value. Figure 7 shows an example of warehouse inventory quantity 12. The meaning of each item of warehouse inventory quantity 12 shown in Figure 7 is as follows:

[0034] The warehouse building is the name of the warehouse building where the product is stored, and each warehouse building is indicated by a unique identification code. The product inventory amount is the number of products stored in the warehouse building.

[0035] The operation database 14 stores information (operation information) relating to the operation of each piece of target equipment. Examples of the operation information in this embodiment are shown in Figs.

[0036] Figure 8 shows "transport vehicle travel time information," which is information on the travel time of transport vehicles between each facility, such as a product yard and a warehouse building. The origin and destination are indicated by the product yard name or warehouse building name. Travel time (loaded with product) is the travel time when a product is loaded. Travel time (empty trolley transport) is the travel time when an empty trolley is being transported. Travel time (unloaded trolley) is the travel time when no trolley is loaded. Here, a value that does not depend on the type of transport vehicle may be used for each travel time. For example, a value obtained by averaging the travel time of transport vehicles based on past performance without distinguishing between vehicle types may be used, or an estimated value or calculated value using a travel simulator may be used.

[0037] Figure 9 shows "destination priority information," which is information on the priority of candidate destination warehouse buildings for product transportation work from the product yard. The fewer the number of candidates, the higher the priority. For example, destination (candidate 1) has a higher priority than destination (candidate 2).

[0038] Figure 10 shows the "Information on each facility" including the number of carts that can be accommodated in each product yard (factory building) and warehouse building, the cart change time for each building, the maximum product acceptance amount, the overhead crane product transport time, and whether or not an automatic crane is installed.

[0039] The integrated product transportation plan 15 is the result of a process performed by the product transportation plan modification device 13 to level the workloads of the destinations and the transport vehicles on the initial product transportation plan 9. The integrated product transportation plan 15 may be created by sequentially executing processes such as leveling, for example, as shown in FIGS. 11 to 13. FIG. 11 is a diagram showing an example of a plan obtained by integrating an additional transport task 10 (see FIG. 5) with the initial product transportation plan 9 (see FIG. 4). The transport vehicle assigned to the additional transport task 10 during integration may be set according to a predetermined rule (for example, a transport vehicle that exists at the source at the task start time is temporarily assigned). FIG. 12 is a diagram showing an example of a plan obtained by performing a process to change the destination warehouse building on the plan of FIG. 11. In the example of FIG. 12, the warehouse building (destination) for the task at the bottom has been changed from T3 to T4. FIG. 13 is a diagram showing an example of a plan obtained by performing a process to change the assigned transport vehicle on the plan of FIG. 12. In the example of FIG. 13, the transport vehicle assigned to the task at the bottom has been changed from V2 to V3. The plan in FIG. 13 may correspond to an integrated product transportation plan 15 that is the result of changes to the destination warehouse building and changes to the allocation of transportation vehicles that perform the work of transporting each product.

[0040] The product transportation plan modification device 13 executes the following process to create and automatically output an integrated product transportation plan 15 that levels out the workload. The operation of the product transportation plan modification device 13 will be described with reference to the flowchart shown in FIG.

[0041] FIG. 14 is a flowchart showing the processing of the product transportation plan change method according to this embodiment (product transportation plan change processing). The flowchart shown in FIG. 14 starts when the product transportation plan change device 13 receives input from the user (including the designation of the target time period). First, the product transportation plan change processing proceeds to the processing of step S1. The product transportation plan change device 13 extracts information about the operation of each piece of equipment from the operation database 14 and acquires the extracted information as operation information. The extracted information includes transportation vehicle travel time information, destination priority information, and information about each piece of equipment. The product transportation plan change device 13 also acquires the above input values. In this embodiment, the input values include input from the user, and specifically include the designated target time period.

[0042] In the process of step S1, the input unit 13a receives input values and operation information in the operation database 14, and outputs the received input values and operation information to the integration unit 13b.

[0043] The integrating unit 13b creates an integrated plan based on the initial product transportation plan 9 and the additional transportation tasks 10. At this time, transport vehicles are assigned to the additional transportation tasks 10 based on the vehicle allocation plan in the initial product transportation plan 9. Specifically, the integrating unit 13b first acquires information about the product yards that are the source of each transportation task in the additional transportation tasks 10. Based on the information about the product yards that are the source of each transportation task, the integrating unit 13b identifies the transport vehicles assigned to the source of each transportation task, and assigns transport vehicles with the same source to the transportation tasks in the additional transportation tasks 10. Furthermore, for transportation tasks in the additional transportation tasks 10 for which no transportation vehicles with the same source exist in the initial product transportation plan 9, the integrating unit 13b assigns transport vehicles with the fewest number of transportation tasks in the initial product transportation plan 9. In this way, the integrating unit 13b creates an integrated plan (see FIG. 11), completing the processing of step S1, and the processing transitions to step S2.

[0044] In the processing of step S2, constraints on the destination capacity of each destination warehouse building are generated based on the input values received by the input unit 13a, the operation information in the operation database 14, and the plan created by the integration unit 13b.

[0045] The constraint condition deriving unit 13c calculates the upper limit of the product acceptance amount and the available time for warehousing work at each destination.

[0046] The upper limit of product acceptance volume at each destination is calculated as follows. A maximum product acceptance volume is set for each destination warehouse building. Here, information on the maximum product acceptance volume can be extracted from the equipment information in the operation database 14. The constraint condition derivation unit 13c subtracts the product inventory volume (see Figure 7) from the maximum product acceptance volume at the destination warehouse building. In addition, each destination warehouse building has a shipping operation to remove stored products. Therefore, the constraint condition derivation unit 13c adds the number of products scheduled to be shipped in the target time period to the value obtained by subtracting the product inventory volume from the maximum product acceptance volume, and defines this as the upper limit of product acceptance volume at the destination warehouse building. Here, the number of products to be shipped can be extracted from the product shipment plan 11.

[0047] The available time for receiving work is calculated as follows. The time range for transportation work for which a change to the product transportation plan is made is defined as the target time period, and the length of the target time period is defined as the target time length. The time used for retrieval work at the destination warehouse building during the target time period is calculated by multiplying the number of products shipped at each destination warehouse building by the overhead crane product transport time of the destination warehouse building extracted from each equipment information (see Figure 10). This calculated value is the time used for retrieval work at each destination warehouse building. The available time for receiving work at each destination warehouse building can be obtained by subtracting the time used for retrieval work from the target time length.

[0048] Here, in warehouse buildings that are not equipped with automated cranes, overhead cranes are operated manually. On the other hand, in warehouse buildings that are equipped with automated cranes, overhead cranes are operated automatically. Therefore, warehouse buildings that are not equipped with automated cranes cannot continue operating during the operator's meal times and break times (hereinafter referred to as "break times, etc."). In contrast, warehouse buildings that are equipped with automated cranes can continue operating even during break times, etc.

[0049] If a warehouse building is not equipped with an automated crane and the target time period includes break times, etc., the available time of the warehouse building can be obtained by subtracting the shipping work usage time and break times, etc. from the target time length. On the other hand, if a warehouse building is equipped with an automated crane, the available time of the warehouse building can be obtained by subtracting the shipping work usage time from the target time length. Here, whether or not a warehouse building is equipped with an automated crane can be determined based on the equipment information in the operation database 14 (see Figure 10). This completes the processing of step S2, and the processing proceeds to step S3.

[0050] In the process of step S3, the workload calculation unit 13d determines whether all product receiving amounts in the target time period are equal to or less than the upper limit of product receiving amounts and whether the product receiving work time at each destination warehouse building is equal to or less than the available time for receiving work. If it is determined that there is even one warehouse building that does not satisfy the constraints (equal to or less than the upper limit of product receiving amounts and equal to or less than the available time for receiving work) (No in step S3), the process proceeds to step S4. If the constraints are satisfied (Yes in step S3), the process proceeds to step S5.

[0051] In the process of step S4, the destination change unit 13e changes the destination of the transportation work from the warehouse building that does not satisfy the constraint conditions to another warehouse building. The transportation work to be changed is selected according to the following priorities (priority keys S4-1 to S4-4, first priority). In addition, destination priority information (FIG. 9) is used.

[0052] The priority key S4-1 is to "lower the priority of transportation work that requires immediate transportation to the destination warehouse building." The priority key S4-2 is to "lower the priority of transportation work in descending order of the value of the product transportation work completion time for each transportation source." The priority key S4-3 is to "lower the priority of transportation work for which the linking of the product part number to be transported has not been completed." The priority key S4-4 is to "lower the priority of additional transportation work 10."

[0053] The priority key S4-1 means that if a change is made to a product transport task that requires immediate transport to the destination warehouse, the impact on the operation of the product yard or warehouse will be significant, so the priority of the task to be changed is lowered (as little as possible as a task to be changed). Here, whether immediate transport to the destination warehouse is required can be determined by the emergency flag.

[0054] The priority key S4-2 is first used to set the product yard for which the product transportation task completion time is to be calculated. Among the transportation tasks in the product transportation plan that exist within the target time period, transportation tasks for which the product yard is the origin are extracted. The travel time of the transport vehicle when transporting the loaded cart from the origin product yard to the destination warehouse building for the extracted transportation task is extracted. This travel time, along with the time required for the transport vehicle to travel when transporting an empty cart or moving a cart without a load, which are separately required for each product transportation task, and the time required for cart replacement at the product yard or warehouse building, are added together to calculate the product transportation task completion time. The travel time for each transportation task can be extracted from the transport vehicle travel time information (see Figure 8). Furthermore, the cart replacement time can be extracted from each facility information (see Figure 10). It is desirable to lower the priority of origin product yards with long product transportation task completion times because they place a heavy burden on operations and the process of changing the destination warehouse building significantly impacts operations.

[0055] The priority order key S4-3 lowers the priority of transportation when the linking of the transportation work with the product to be transported has not been completed. In other words, the priority order key S4-3 lowers the priority of transportation work for which the candidate destination warehouse building has not been determined. Even if the destination of such transportation work is changed, the effect of load leveling at the destination warehouse building is unlikely to be achieved, so it is desirable to lower the priority order. Here, it is possible to determine whether the linking of the product part number of the product to be transported has been completed using the confirmation flag.

[0056] The priority key S4-4 lowers the priority of the additional transport task 10. Because the existing transport task (the transport task in the initial product transport plan 9) is scheduled for transport earlier, changing the destination of the additional transport task 10 will not have the effect of leveling the load on the destination warehouse building. Therefore, it is desirable to lower the priority of the additional transport task 10.

[0057] After the destination is changed in step S4 (the workload at the destination is leveled), the process returns to step S3, where a determination is made regarding the constraint conditions.

[0058] A specific example of the processing in step S4 is as follows. In the example of FIG. 11, the target time period is from 19:00 to 23:00. The set time length is four hours. Assume that the processing in step S3 determines that destination warehouse T3 does not satisfy the constraints. In FIG. 11, transport operations whose destination warehouse T3 exists are in the fifth, sixth, and eighth rows. Among these, the transport operation for which the destination warehouse change process is to be performed is determined based on the above priority order. First, the priority order of the transport operation whose emergency flag is TRUE (line 5) is lowered. Furthermore, the priority order of the transport operation (line 6) that is additional transport operation 10 is lowered, and the transport operation in line 8 becomes the target for the destination warehouse change process. Based on the candidate destinations with F5 as the source product yard in the destination priority information (FIG. 9), the destination warehouse of the transport operation in line 8 is changed from T3 to T4. FIG. 12 shows a plan in which the destination warehouse change process has been performed (hereinafter, this may be referred to as the "destination change plan").

[0059] In the processing of step S5, the load leveling calculation unit 13f calculates the product transportation work completion time of each transportation vehicle and determines a transportation workload value of each transportation vehicle based on the calculated value. The transportation workload value is a value indicating the transportation workload. The load leveling calculation unit 13f calculates an evaluation value based on the transportation workload value. The specific calculation method is as follows.

[0060] Among the transportation tasks that exist within the target time period of the product transportation plan, transportation tasks that have been assigned transportation vehicles and have been linked to the products to be transported are extracted. The product transportation task completion time for the extracted group of transportation tasks is calculated. The method for calculating the product transportation task completion time is the same as that described for priority key S4-2 above. The ratio of the product transportation task completion time for each transportation vehicle to the set time length is calculated, and this ratio is determined as the transportation workload value. The load leveling calculation unit 13f calculates the transportation workload value for all transportation vehicles assigned to transportation tasks within the target time period of the product transportation plan.

[0061] The load leveling calculation unit 13f calculates an evaluation value based on the transportation workload value of each transportation vehicle. Specifically, the evaluation value is calculated by subtracting the average transportation workload value from the transportation workload of each transportation vehicle, squaring the result, adding up all the squared values, and dividing the result by the number of transportation vehicles. The square root of this result is the evaluation value. In other words, in this embodiment, the evaluation value is the standard deviation of the transportation workload values.

[0062] In the process of step S6, it is determined whether the evaluation value of step S5 is equal to or less than a threshold value. If there is even one delivery vehicle whose evaluation value exceeds the threshold value (No in step S6), the process proceeds to step S7. If the evaluation value is equal to or less than the threshold value (Yes in step S6), the process proceeds to step S8.

[0063] In the process of step S7, the allocation change unit 13g changes some of the transport work of a transport vehicle with a high transport work load to another transport vehicle. The transport work to be changed is selected as the transport work that is scheduled to be transported at the latest time among the transport work that are the target of the process of changing the assigned transport vehicle. The transport vehicle to be changed is selected as the transport vehicle with the lowest transport work load.

[0064] After the assigned transport vehicles are changed in step S7 (the workloads of the transport vehicles are leveled), the process returns to step S5, where the transport workload value and evaluation value of each transport vehicle are calculated.

[0065] A specific example of the processing in step S7 is as follows. In the example of FIG. 12, first, transport work whose confirmation flag is TRUE is extracted from the transport destination change plan. In step S5, the transport workload value and evaluation value of each transport vehicle are calculated, and in step S6, it is determined that the evaluation value of the transport vehicle exceeds a threshold (the standard deviation is greater than a predetermined threshold, and the workload varies greatly among transport vehicles). Here, the threshold corresponds to the allowable upper limit of workload variation among transport vehicles, which is predetermined based on past performance data, etc. Furthermore, it is determined that the vehicle with the largest transport workload value is V2, and the transport work scheduled for transport at the latest time (line 8) is subject to the process of changing the assigned transport vehicle. Since it is determined that the transport vehicle with the smallest workload value is V3, the transport vehicle for the target transport work (line 8) is changed from V2 to V3. FIG. 13 shows a plan in which the process of changing the assigned transport vehicle has been performed.

[0066] In the process of step S8, the transfer order adjustment unit 13h adjusts (rearranges) the transfer order based on the input values and the plan created by the allocation change unit 13g. The transfer order is rearranged according to the following priorities (priority order keys S8-1 to S8-4, second priority).

[0067] The priority key S8-1 is to "increase the priority in ascending order of the start time of the work time slot for each transportation task." The priority key S8-2 is to "decrease the priority of transportation tasks for which the assigned transportation vehicle has been changed." The priority key S8-3 is to "decrease the priority of additional transportation task 10." The priority key S8-4 is to "increase the priority in ascending order of the transportation order originally set in the initial product transportation plan 9 and additional transportation task 10."

[0068] The transportation order is adjusted according to the priority order keys S8-1 to S8-4. This completes the processing of step S8, and the result is output by the output unit 13i. Here, the processing of step S8 may be omitted. In this case, the plan in which the processing to change the assigned transportation vehicles has been carried out corresponds to the final integrated product transportation plan 15.

[0069] The integration unit 13b integrates the initial product transportation plan 9 and the additional transportation work 10, and then the destination change unit 13e changes the destination warehouse building and the allocation change unit 13g changes the assigned transportation vehicle. The output unit 13i outputs the integrated product transportation plan 15 in which the transportation order has been adjusted by the transportation order adjustment unit 13h.

[0070] The output unit 13i may output the integrated product transportation plan 15 with the adjusted transportation order via a network to a terminal device used by an operator operating the product transportation plan modification device 13 or an operator of a transport vehicle. Here, the terminal device is used by the operator operating the product transportation plan modification device 13 to confirm the changed product transportation plan, and by the operator of the transport vehicle to confirm the changed product transportation plan as a changed command.

[0071] The transport vehicle may be an automated guided vehicle that autonomously travels along a route set based on three-dimensional map data from a LiDAR (Light Detection and Ranging) sensor and information from a Global Navigation Satellite System. In this case, the output unit 13i may output the revised product transport plan to a vehicle control server that sets a travel route or instructs the automated guided vehicle to start and stop via wireless communication.

[0072] The effects of the present disclosure will be specifically described below based on examples, but the present disclosure is not limited to these examples.

[0073] This example shows the results of creating an integrated product transportation plan 15 using the method of the above embodiment for product transportation by transport vehicles from a product factory to a warehouse building where the products are stored. The integrated product transportation plan 15 was created for 44 target time periods, and as a comparative example, a product transportation plan was created manually for the same 44 target time periods.

[0074] A simulator was used that can model logistics facilities and perform simulations of product logistics on a computer. An integrated product transportation plan 15 based on the method of the above embodiment was input into the simulator, and simulation results were obtained. In the simulation, the time required for all transportation vehicles in each target time period from the start of product transportation to the completion of all transportation work was calculated. Hereinafter, this time value will be referred to as the transportation work completion time for each target time period. Similarly, manually created product transportation plan results were input into the simulator, and simulation results were obtained. Similarly, the transportation work completion time for each target time period was calculated and used for comparison.

[0075] In Figure 15, the horizontal axis shows the ratio of the transportation work completion time during the target time period to the target time length, divided into predetermined ranges. The number of corresponding cases is shown in a histogram as a ratio to the total number of cases (44 cases) during the target time period, and the comparative example and the example are compared within each range. Portions of the horizontal axis exceeding 100% indicate that the transportation work completion time exceeded the target time length (excess).

[0076] The results in Figure 15 show that in manual product transportation planning, approximately 84% of the transportation task completion times exceeded the set time length, whereas in product transportation planning using the method of the above embodiment, this was reduced to approximately 68%.

[0077] Figure 16 shows a scatter plot comparing the transportation task completion times for all target time periods. The horizontal axis represents the ratio of the transportation task completion time to the target time length for each target time period in the manual product transportation plan. The vertical axis represents the ratio of the transportation task completion time to the target time length for each target time period in the product transportation plan using the method of the above embodiment.

[0078] The points in the area above the diagonal line in Figure 16 indicate that the time to complete the transportation work using the manual product transportation plan is shorter. The points in the area below the diagonal line indicate that the time to complete the transportation work using the product transportation plan according to the method of the above embodiment is shorter (improved compared to the comparative example).

[0079] Furthermore, points within the region shown in (A) of Figure 16 indicate that the time required to complete the transportation work in the manual product transportation plan is shorter than (does not exceed) the target time length. Points within the region shown in (B) of Figure 16 indicate that the time required to complete the transportation work in the product transportation plan using the method of the above embodiment is shorter than (does not exceed) the target time length. Points outside both regions (A) and (B) (points within the regions surrounded by diagonal lines) indicate that the workload may be excessive at the initial product transportation plan 9 stage.

[0080] 16, it can be seen that in the comparative example, the workload distribution of the transport vehicles is insufficient, and as a result, the transport task completion time tends to exceed the target time length. On the other hand, in the example, there are fewer cases where the transport task completion time is greater than the target time length, and there are multiple cases where the transport task completion time is significantly reduced. Therefore, it is considered that the example is more likely to stably create a plan in which the load is appropriately leveled than the comparative example.

[0081] As described above, the product transportation plan modification device 13, program, and product transportation plan modification method according to this embodiment use the above-described configuration and processes to automatically modify the allocation of transportation vehicles from source to destination and change the workload at the destination. In other words, this embodiment can automatically equalize the workload at the destination and the workload of the transportation vehicles. Furthermore, because workload leveling can be performed automatically, the burden of manually modifying product transportation plans, which has traditionally been done manually, is eliminated. This also reduces the risk of congestion in the factory's product yard, making it possible to avoid, as much as possible, factory production line stoppages and adverse effects on product quality.

[0082] Although the embodiments of the present disclosure have been described based on the drawings and examples, it should be noted that those skilled in the art would easily be able to make various modifications or alterations based on the present disclosure. Therefore, it should be noted that these modifications and alterations are included within the scope of the present disclosure. For example, the functions included in each component or step can be rearranged so as not to cause logical inconsistencies, and multiple components or steps can be combined or divided into one. The embodiments of the present disclosure can also be realized as a storage medium (e.g., a non-transitory computer-readable recording medium) on which a program executed by a processor included in an apparatus is recorded. It should be understood that these are also included within the scope of the present disclosure. [Explanation of symbols]

[0083] 1. Factory 1a~1d Factory building (product yard) 2 Warehouse 2a~2c Warehouse building (warehouse building) 2d Temporary shipping storage area 3a~3d, 4a~4c Overhead crane 5a, 5b Transport vehicles 6a~6c Cart 7. Loading Crane 8. Carrier 9. Initial Product Transportation Plan 10 Additional transportation work 11 Product Shipping Plan 12 Warehouse inventory 13 Product transportation plan change device 13a Input section 13b Integration Department 13c Constraint condition derivation part 13d Workload calculation part 13e Destination Change Section 13f Load level calculation section 13g Allocation change section 13h Transport order adjustment section 13i output section 14 Operational Database 15 Integrated Product Transportation Planning

Claims

1. A product transportation plan change device that changes an initial product transportation plan for a transportation vehicle from a transportation source to a transportation destination in a target time period for optimization, an input unit that receives input values including the initial product transportation plan and the product shipping plan and operation information including information on each facility; a destination change unit that, when determining that there is a destination that does not satisfy the constraints using the upper limit of product acceptance volume at each destination and the available time for warehousing work calculated based on the input values and the operation information, changes the destination that does not satisfy the constraints to another warehouse building for transportation work selected according to a predetermined first priority; and an allocation change unit that changes a transport vehicle with a high transport workload to another transport vehicle when an evaluation value indicating the variation in workload among the transport vehicles exceeds an allowable upper limit value.

2. 2. The product transportation plan change device according to claim 1, further comprising an integration unit that creates an integrated plan based on the initial product transportation plan and additional transportation work that is added at the time of execution of the change process.

3. 3. The product transportation plan change device according to claim 2, wherein the predetermined first priority includes lowering the priority of transportation work that requires urgent transportation, lowering the priority of transportation work in descending order of the value of the product transportation work completion time for each transportation source, lowering the priority of transportation work for which linking of product numbers of products to be transported has not been completed, and lowering the priority of the additional transportation work.

4. 4. The product transportation plan change device according to claim 2 or 3, further comprising an output unit that outputs an integrated product transportation plan in which the transportation order is adjusted according to a predetermined second priority, after the integration unit integrates the initial product transportation plan and the additional transportation work, and the destination change unit performs a process to change the destination warehouse building and the allocation change unit performs a process to change the assigned transportation vehicle.

5. 5. The product transportation plan change device according to claim 4, wherein the predetermined second priority includes increasing the priority in ascending order of the start time of the work time slot of each transportation task, decreasing the priority of transportation tasks for which the assigned transportation vehicle has been changed, decreasing the priority of the additional transportation tasks, and increasing the priority in ascending order of the transportation order originally set in the initial product transportation plan and the additional transportation tasks.

6. The product transportation plan change device according to claim 1 , wherein the evaluation value is a standard deviation of the value indicating the transportation workload.

7. A product transportation plan change device as described in claim 4, wherein the evaluation value is the standard deviation of the value indicating the transportation workload.

8. A product transportation plan change device as described in Claim 5, wherein the evaluation value is the standard deviation of the value indicating the transportation workload.

9. a product transportation plan modification device that modifies an initial product transportation plan by a transportation vehicle from a transportation source to a transportation destination during a target time period for optimization; receiving input values including the initial product transportation plan and product shipping plan and operation information including information on each facility; When it is determined that there is a destination that does not satisfy the constraints using the upper limit of product acceptance volume at each destination and the available time for warehousing work calculated based on the input values and the operation information, for transportation work selected according to a predetermined first priority, change the destination that does not satisfy the constraints to another warehouse building; and when the evaluation value indicating the variation in workload among the transport vehicles exceeds an allowable upper limit, changing the transport vehicle with a high transport workload to another transport vehicle.

10. A method for changing a product transportation plan for optimizing an initial product transportation plan by a transportation vehicle from a transportation source to a transportation destination during a target time period, comprising: receiving input values including the initial product transportation plan and product shipping plan and operation information including information on each facility; When it is determined that there is a destination that does not satisfy the constraints using the upper limit of product acceptance volume at each destination and the available time for warehousing work calculated based on the input values and the operation information, for transportation work selected according to a predetermined first priority, change the destination that does not satisfy the constraints to another warehouse building; and changing a transport vehicle with a high transport workload to another transport vehicle when an evaluation value indicating the variation in workload among the transport vehicles exceeds an allowable upper limit value.