Configuration decision support method and configuration decision support device for logistics simulation device

Abstract

To provide a configuration determination support method and a configuration determination support device for a physical distribution simulation device, capable of configuring an accurate physical distribution simulation device without spending a lot of man hours.SOLUTION: A configuration determination support method for a physical distribution simulation device according to the present invention includes: an index calculation step for calculating an index by considering at least one of a combination of work assignment to each facility, a work efficiency determined by the work assignment to each facility, and work completion time determined by the work assignment to each facility by using information on a parcel to be moved; a determination step for determining which one of a work assignment rule for determining a work to be performed next by each facility or a work schedule which designates a facility for implementing each work and execution time of each work or work sequence is used for assigning a work to each facility on the basis of the index calculated by the index calculation step; and an output step for outputting the determination result in the determination step.SELECTED DRAWING: Figure 11

Description

[Technical Field]

[0001] The present invention relates to a configuration decision support method and a configuration decision support device for a logistics simulation device that visualizes the state of a logistics facility on a computer. [Background technology]

[0002] In general, in the manufacturing industry, products manufactured in factories are packaged and then transported to a product storage area (product yard or product warehouse) using transport vehicles or carts such as AGVs (Automatic Guided Vehicles), where they are stored until the day of removal. On the removal day, the products are removed from the product storage area and loaded onto transport vehicles or carriers using loading and unloading equipment, and then transported to a customer site, logistics center, or other location. The distance and time traveled by products up to the removal date are shorter than the time traveled by products after removal. Furthermore, the time required for product transportation after removal to a customer site, logistics center, or other location is significantly longer than other tasks (e.g., loading onto transport vehicles or carriers). Therefore, the route selection for product transportation is a major factor in achieving logistics efficiency and capacity expansion. Given this background, product logistics plans often focus on route selection methods.

[0003] However, when it comes to product movement up to the removal date, there is little difference in the processing time for loading and unloading operations at each facility, making it difficult to determine which operation is causing delays in the overall logistics process. Particularly in large factories, numerous and diverse pieces of equipment operate simultaneously, and products are moved by coordinating their work. For this reason, for example, a delay in the completion timing of a task can cause equipment to wait, which can lead to a chain reaction of delays in other tasks and result in significant delays across the entire facility. To prevent such delays, it is important to confirm in advance whether production plans are likely to cause delays, and to investigate the cause when delays occur during operation. However, with numerous and diverse pieces of equipment in operation, such tasks are difficult to perform manually.

[0004] To address these challenges, a technology has been proposed that uses a computer to simulate the progress of work across an entire facility and reflects the results in operations. Specifically, Patent Document 1 describes a technology related to a simulation system for guided vehicles that transport workpieces between processing equipment. The technology described in Patent Document 1 creates a schedule for guided vehicles, then runs a simulation to check for interference between the vehicles in advance and then modifies the schedule to avoid interference. Furthermore, Patent Document 2 describes a technology related to a simulation that determines the layout of processing lines in semiconductor factories. Since simulations that reproduce complex manufacturing processes require a long calculation time, the technology described in Patent Document 2 simplifies the target to reduce the calculation time. Specifically, the technology described in Patent Document 2 represents the target as a graph with processing equipment as vertices and transport paths as edges, and calculates the transport volume per unit time for each transport section using linear programming.

[0005] The technologies described in Patent Documents 1 and 2 both create transportation schedules and run simulations based on them. However, while computer programs are used to create transportation schedules, creating such programs often requires a great deal of effort. For example, when various complex constraints need to be satisfied, the computer programs tend to become complex and large-scale, requiring a great deal of man-hours to create. Furthermore, in the field of production logistics planning, the number of combinations of schedule candidates is often enormous, and the processing time of the computer programs tends to be long in order to examine each combination. On the other hand, while there are computer programs that can generate schedules in a short time regardless of the number of combinations, the processing time of such computer programs tends to be very complex.

[0006] For this reason, technologies for performing simulations without creating transportation schedules have also been proposed. Specifically, Patent Document 3 describes a technology for optimizing variables used in rule conditional expressions in operations for human-centered production lines, in which rules determine the next location and task that workers should perform. Patent Document 4 also describes a technology for performing simulations by determining tasks to be performed using rules based on the transportation load between processes. Both of the technologies described in Patent Documents 3 and 4 simulate the next tasks to be performed by personnel and equipment based on rules. The rules used here are for making short-term decisions, such as which product to transport next and where to transport that product. Therefore, the load on a computer to implement these methods is lower than scheduling, which determines the order of tasks for a target period and the execution times of multiple tasks. However, because decisions are made from a short-term perspective, these methods may result in inefficient task allocation compared to the technologies described in Patent Documents 1 and 2. [Prior art documents] [Patent documents]

[0007] [Patent Document 1] JP 2013-49500 A [Patent Document 2] Japanese Patent Application Laid-Open No. 2017-117397 [Patent Document 3] Japanese Patent Application Publication No. 11-306162 [Patent Document 4] Japanese Patent Application Laid-Open No. 2001-117624 [Patent Document 5] Japanese Patent Application Laid-Open No. 2005-350158 Summary of the Invention [Problem to be solved by the invention]

[0008] As described above, the technologies described in Patent Documents 1 to 4 all use only one of scheduling and rules to perform work allocation processing and visualize the status of work, but scheduling and rules each have their own advantages and disadvantages. Furthermore, since the criteria for appropriately using scheduling and rules in work allocation processing are unclear, there is a problem in that it is unclear which one should be used to simulate efficient operations. Therefore, the inventors of the present invention conceived of a way to configure a logistics simulation device that is accurate without incurring a large amount of man-hours by appropriately determining whether to use scheduling or rules in work allocation processing.

[0009] The present invention has been made to solve the above-mentioned problems, and its object is to provide a configuration decision support method and a configuration decision support device for a logistics simulation device that can configure a highly accurate logistics simulation device without requiring many man-hours. [Means for solving the problem]

[0010] The configuration determination support method for a logistics simulation device according to the present invention is a configuration determination support method for a logistics simulation device that visualizes on a computer the status of each piece of equipment in a logistics facility that includes equipment for transporting luggage, equipment for storing luggage, and equipment for transferring luggage, and includes: an index calculation step that uses information about luggage to be moved to calculate an index that takes into account at least one of the combination of work assignments to each piece of equipment, the work efficiency determined by the work assignments to each piece of equipment, and the work completion time determined by the work assignments to each piece of equipment; a determination step that determines, based on the index calculated in the index calculation step, whether to assign work to each piece of equipment in accordance with a work assignment rule that determines the next piece of work to be performed by each piece of equipment, or a work schedule that specifies the equipment in charge of each piece of work and the execution time or order of each piece of work; and an output step that outputs the result of the determination in the determination step.

[0011] The index calculation step preferably calculates at least one index from the number of combinations of work assignments to each piece of equipment, the work efficiency distribution for each combination of work assignments to each piece of equipment that satisfies the constraints when simultaneously assigning multiple pieces of equipment to one task, and the distribution of the time required for the equipment to complete the task when the task is assigned to the equipment.

[0012] The decision step may include a step of calculating a centralized evaluation value that can determine whether it is better to select the work assignment rule or the work schedule, and selecting the work assignment rule or the work schedule according to a threshold value of the evaluation value.

[0013] The equipment for transporting the cargo is a transport vehicle whose towing unit and pallet can be separated, and when determining a method for allocating transport vehicles to pallet transport work and a method for allocating transport lots to pallets, the index calculation step and the determination step can be executed.

[0014] The configuration decision support device for a logistics simulation device according to the present invention is a configuration decision support device for a logistics simulation device that visualizes on a computer the status of each piece of equipment in a logistics facility that includes equipment for transporting luggage, equipment for storing luggage, and equipment for transferring luggage, and is equipped with an index calculation means that uses information about luggage to be moved to calculate an index that takes into account at least one of the combination of work assignments to each piece of equipment, the work efficiency determined by the work assignments to each piece of equipment, and the work completion time determined by the work assignments to each piece of equipment, based on the index calculated by the index calculation means, a decision means that decides whether to assign work to each piece of equipment according to a work assignment rule that determines the next piece of work that each piece of equipment will perform, or a work schedule that specifies the equipment in charge of each piece of work and the execution time or work order of each piece of work, and an output means that outputs the decision result of the decision means.

[0015] The index calculation means preferably calculates at least one index from the number of combinations of work assignments to each piece of equipment, the work efficiency distribution for each combination of work assignments to each piece of equipment that satisfies the constraints when simultaneously assigning multiple pieces of equipment to one piece of work, and the distribution of the time required for the equipment to complete the work when the work is assigned to the equipment.

[0016] The decision means may calculate a unified evaluation value that can determine whether it is better to select the work assignment rule or the work schedule, and select the work assignment rule or the work schedule according to a threshold value of the evaluation value.

[0017] The equipment for transporting the cargo is a transport vehicle in which the towing unit and the pallet can be separated, and the index calculation means and the determination means preferably perform processing when determining a method for allocating transport vehicles to pallet transport work and a method for allocating transport lots to pallets. [Effects of the Invention]

[0018] According to the configuration decision support method and configuration decision support device for a logistics simulation device of the present invention, a highly accurate logistics simulation device can be configured without requiring many man-hours. [Brief explanation of the drawings]

[0019] [Figure 1] FIG. 1 is a schematic diagram showing the configuration of a logistics facility that is the target of a logistics simulation device according to one embodiment of the present invention. [Figure 2] FIG. 2 is a schematic diagram showing an example of the configuration of the transporter vehicle shown in FIG. [Figure 3] FIG. 3 is a block diagram showing the configuration of a logistics simulation device for visualizing the state of each piece of equipment in the logistics facility shown in FIG. [Figure 4] FIG. 4 is a diagram illustrating an example of transportation lot information. [Figure 5] FIG. 5 is a flowchart showing the flow of a logistics simulation performed by the logistics simulation device shown in FIG. [Figure 6] FIG. 6 is a diagram showing the operations that occur for each transport lot. [Figure 7] FIG. 7 is a diagram showing an example of a transportation work schedule. [Figure 8] FIG. 8 is a diagram showing an example of a transportation work schedule. [Figure 9] FIG. 9 is a diagram showing an example of a list of pallets available to the transport vehicle. [Figure 10] FIG. 10 is a diagram showing an example of an efficiency value record for a combination of work assignments. [Figure 11] FIG. 11 is a block diagram showing the configuration of a configuration decision support device for a logistics simulation system according to one embodiment of the present invention. DETAILED DESCRIPTION OF THE INVENTION

[0020] A configuration decision support method and a configuration decision support device for a logistics simulation device according to an embodiment of the present invention will be described below with reference to the drawings.

[0021] [Logistics equipment] First, with reference to FIG. 1, the configuration of a physical distribution facility that is the target of a physical distribution simulation device according to one embodiment of the present invention will be described.

[0022] FIG. 1 is a schematic diagram showing the configuration of a logistics facility that is the target of a method for configuring a logistics simulation device according to one embodiment of the present invention. The cargo handled by the logistics facility 1 shown in FIG. 1 is coils C, which are steel products. The cargo-moving equipment is broadly classified into cargo handling equipment and transportation equipment. The cargo handling equipment is an overhead crane 2 and a loading crane 3, and the transportation equipment is a transport vehicle 4. The coils C manufactured in the factory are transported into product warehouses 5a-5c by the transport vehicle 4. The product warehouses 5a-5c serve as buffers for temporarily storing the coils C until shipment and are located along the shipping berths (berths A-C) where a transport ship 6 is moored. Each of the product warehouses 5a-5c is configured with multiple adjacent buildings (buildings), and each building is equipped with a vehicle entrance / exit 7, which is an area through which an overhead crane 2 and one transport vehicle 4 can enter. The overhead crane 2 is used to move the coils C transported by the transport vehicle 4 within the building and to transport coils C that are close to being shipped to the shipping berth. When a transport ship 6 loading the coils C is anchored far from the building where the coils C are stored, the overhead crane 2 loads the coils C onto a transport vehicle 4, and the transport vehicle 4 moves the coils C to the shipping berth where the transport ship 6 is anchored.

[0023] FIG. 2 shows an example of the configuration of the transport vehicle 4. As shown in FIG. 2, the transport vehicle 4 has a structure in which the towing unit 4a and the pallet 4b, which is the cargo loading unit, can be separated. The towing unit 4a connects a pallet 4b loaded with coils C at the factory and transports the pallet 4b to the designated product warehouse. When the towing unit 4a arrives at the product warehouse, it enters the vehicle entrance / exit 7 and unloads the pallet 4b. After unloading the pallet 4b, the towing unit 4a either connects another pallet 4b placed in the same vehicle entrance / exit 7 or moves out of the vehicle entrance / exit 7 to the vehicle entrance / exit 7 where the pallet 4b is placed to transport another pallet 4b. The coils C loaded on the pallet 4b placed in the product warehouse are moved into the product warehouse by the overhead crane 2 (this process is called warehousing). Once all of the coils C loaded on the pallet 4b have been moved into the product warehouse, the towing unit 4a loads an empty pallet 4b onto the pallet 4b and exits the vehicle entrance / exit 7. This towing unit 4a may be different from the towing unit 4a that carried the pallet 4b to the vehicle entrance 7.

[0024] Because the transport vehicle 4 has a structure in which the towing unit 4a and the pallet 4b can be separated, the towing unit 4a can move (travel) and load onto the pallet 4b simultaneously. Vehicles with a structure in which the towing unit and the load carrying unit cannot be separated, such as a typical truck, must stop during loading and unloading operations. Compared to such vehicles, a separable vehicle allows for more efficient transport. However, the transport operations of a separable vehicle are easily affected by other transport operations. This is because the same pallet 4b is used by multiple towing units 4a. For example, in an operation in which towing unit V1 transports pallet P1 loaded with a certain product from a factory to a product warehouse, and then towing unit V2 transports pallet P1, which has already unloaded the product at the product warehouse, back to the factory to load another product. In this case, if the work of towing unit V1 is delayed, causing a delay in the transport of pallet P1, this delay can lead to a chain reaction of delays in the loading (unloading) operations at the product warehouse and subsequent delays in the work of towing unit V2. In addition, since multiple towing units and pallets enter the vehicle entrance and exit of the same factory or product warehouse, the logistics facility 1 shown in Figure 1 is configured in such a way that work delays at each facility are likely to affect each other.

[0025] In a logistics facility 1 with this type of configuration, if a certain piece of equipment is delayed, it is difficult to determine the root cause, as the delays have a chain reaction that affects other pieces of equipment. For this reason, an approach is sometimes taken in which the status of each piece of equipment in the logistics facility 1 is visualized on a computer through simulation, and the cause of the work delay is analyzed. In the case of simulations targeting production, logistics, etc., it is necessary to determine which equipment the work required for production or logistics should be assigned to, and in what order or at what time the work should be performed. In this respect, simulations targeting production, logistics, etc. differ from physical model simulations, in which the movement of the target can be expressed using equations, etc.

[0026] [Logistics simulation device] Next, with reference to FIGS. 3 and 4, the configuration of a logistics simulation device for visualizing the state of each facility in the logistics facility 1 shown in FIG. 1 will be described.

[0027] Fig. 3 is a block diagram showing the configuration of a logistics simulation device for visualizing the state of each piece of equipment in the logistics facility 1 shown in Fig. 1. As shown in Fig. 3, the logistics simulation device is used to check the situation that occurs in each piece of equipment in the logistics facility 1 in response to a given situation (waiting, occurrence of downtime, full storage space, etc.), and is equipped with an information storage device 100. The information storage device 100 is a storage device that stores information required for creating plans and executing simulations, and is equipped with a facility information database (facility information DB) 100a, a baggage information database (baggage information DB) 100b, and a work information database (work information DB) 100c.

[0028] The equipment information DB 100a stores information on the transportation equipment that transports the coil C, the storage equipment that stores the coil C, and the loading and unloading equipment that transfers the coil C. Specifically, the equipment information DB 100a stores operation information for each piece of equipment, information on the specifications of each piece of equipment, information on work allocation constraints for each piece of equipment, and information on work allocation rules for each piece of equipment. The operation information for each piece of equipment includes information on the number, current location, and downtime / maintenance of each piece of equipment (overhead crane 2, loading crane 3, and transport vehicle 4). The information on the specifications of each piece of equipment includes information on the cycle time (in the case of a crane), traveling speed, maximum transport weight, and capacity (in the case of a product warehouse and storage yard) of each piece of equipment. The work allocation constraint information for each piece of equipment includes information on constraints, such as limiting the combination of equipment that can perform work simultaneously. The information on the work allocation rules for each piece of equipment includes information on rules that determine the next work that equipment will perform based on work priority, etc., without creating a work plan.

[0029] The cargo information DB 100b stores information about the coils C that are scheduled to be moved. Specifically, the cargo information DB 100b stores transport lot information and scheduled shipping product information. The transport lot information includes information about the coils C that are being transported from the factory to the product warehouse, organized into pallets. The scheduled shipping product information includes information about the carrier, hold, berth, and loading crane used to transport the coils C, as well as information about the order in which the coils C will be loaded onto the carrier and the scheduled loading time.

[0030] The work information DB 100c stores information about required transportation work and performance data of past transportation work. Specifically, the work information DB 100c stores a completed work list, a scheduled work list, and a work plan. The completed work list includes information about the target product, equipment used, transport source, transport destination, start time, and end time for completed work. The scheduled work list includes information about the target product, equipment used, transport source, transport destination, scheduled start time, and scheduled end time for work to be performed. The work plan includes information about the work plan to be executed in the logistics simulation.

[0031] The contents of each database in the information storage device 100 are updated as the work status of each facility changes. When a transport vehicle 4 starts or finishes its assigned transport work or passes a set point, it transmits that information to the information storage device 100 via a transport vehicle communication device 101 installed on the transport vehicle 4. The information storage device 100 updates each database according to the transmitted information. Similar communication devices (overhead crane communication device 102, loading crane communication device 103) are also installed on the overhead crane 2 and loading crane 3, and transmit information to the information storage device 100 when the crane starts or finishes movement or when cargo is loaded or unloaded.

[0032] The logistics simulation device of this embodiment includes an input unit 104. The input unit 104 is a device for inputting various operational conditions to be applied when performing a logistics simulation. In this embodiment, the input unit 104 includes a simulation condition input unit 104a and a rule input unit 104b.

[0033] The simulation condition input unit 104a is a device for inputting situations that may occur in future operations. Examples of information to be input include time periods when the loading crane 3 will be stopped due to rain or strong winds, time periods when the loading crane 3 will be stopped due to equipment failure, information regarding the addition of priority shipping products (shipping deadline date, product quantity setting, etc.), and information regarding changes in the proportion of production types (change amount, change time period, etc.). This makes it possible to visualize, through a logistics simulation, what phenomena will occur throughout the logistics facility 1 if the above situations occur. Of course, it is also possible to run a logistics simulation assuming that the current operating conditions continue without change.

[0034] The rule input unit 104b inputs rules that each piece of equipment follows when performing work. For example, the rule input unit 104b sets rules that determine which product the overhead crane 2 should prioritize in handling work, or which piece of equipment to select when there is multiple equipment that can perform the work. The set rules are stored as work allocation rules in the equipment information DB 100a of the information storage device 100.

[0035] The logistics simulation device of this embodiment includes an operation generation unit 105 and a simulation plan generation unit 106. The operation generation unit 105 generates operation data for one operation unit using data stored in the information storage device 100. For example, for an operation by a transport vehicle 4, the operation generation unit 105 generates operation data using transport lot information. An example of transport lot information is shown in FIG. 4. As shown in FIG. 4, records of transport lot information are generated for each product (product ID), and a transport lot ID that groups each product together for each pallet is assigned. The type of pallet that can carry each transport lot is also specified. In the example shown in FIG. 4, the transport lot information includes information regarding the transport lot ID, total lot weight, product ID, pallet type, number of products in the lot, origin entrance, destination warehouse building number, and scheduled removal time.

[0036] The simulation plan generation unit 106 generates a work plan by determining the equipment that will perform the work and the order or date and time of execution for the work generated by the work generation unit 105. The work generation unit 105 stores the work plan created by the simulation plan generation unit 106 in the work information DB 100c of the information storage device 100.

[0037] The logistics simulation device of this embodiment includes a simulation unit 107. The simulation unit 107 executes a computer simulation of work at each piece of equipment in the logistics facility 1, based on the work data for each work unit generated by the work generation unit 105, the work plan generated by the simulation plan generation unit 106, and the work allocation rules for the equipment stored in the information storage device 100.

[0038] The simulation unit 107 stores model group A and model group B, which are computer programs that model the behavior of each piece of equipment and run them on a computer. The simulation unit 107 executes these computer programs. Model group A determines the task allocation, execution order, or execution date and time based on the task allocation rules. Model group B determines the task allocation, execution order, or execution date and time based on the task plan generated by the simulation plan generation unit 106. The task schedule may not be generated but may be provided externally. The results of the computer simulation are visualized by the simulation information output unit 108, providing the necessary information to the user of the logistics simulation device.

[0039] [Flow of logistics simulation] Next, the flow of the logistics simulation performed by the logistics simulation device will be described with reference to FIG.

[0040] FIG. 5 is a flowchart showing the flow of a logistics simulation performed by the logistics simulation device shown in FIG. 3. When performing a logistics simulation, first, the work generation unit 105 extracts necessary data from three types of databases in the information storage device 100 (step S1). Next, the work generation unit 105 generates work and constraint conditions for each piece of equipment during the time period to be visualized based on the extracted data (step S2). Next, the simulation plan generation unit 106 generates a plan for the generated work (step S3). Next, the simulation unit 107 performs a computer simulation using the work schedule or work allocation rules (step S4). Finally, the simulation information output unit 108 outputs the results of the computer simulation (step S5).

[0041] Here, it is necessary to determine the configuration of the logistics simulation device by determining whether to use the work schedule or the work allocation rules to execute the work assignment process. Below, a description is given of a configuration determination support method and a configuration determination support device for a logistics simulation device that support the determination of whether to use the work schedule or the work assignment rules to execute the work assignment process.

[0042] <Configuration decision support method and configuration decision support device for logistics simulation device> First, the work schedule and work allocation rules that are to be determined when the work allocation process is executed will be described.

[0043] [Work Schedule] First, an example of a work schedule will be described with reference to FIGS.

[0044] Patent Document 5 describes a technology for creating a work schedule for a transport vehicle with separable pallets. Patent Document 5 also describes a method for creating a work schedule for a generated transport lot, which determines the allocation of pallets to load the transport lot and the transport vehicle to move the pallet, as well as the execution time of each task. Because the technology described in Patent Document 5 can accommodate a very large number of task assignment combinations, it employs three types of calculation processing steps to minimize the schedule generation time. If a computer program for performing such planning processing is available before building a simulation device, the simulation device can be built using that computer program. However, if such a computer program is not available, a computer program for complex processing must be developed from scratch, which places a heavy burden on building the simulation device.

[0045] In the case of transport vehicle operations, products with the same origin and destination are loaded onto a single pallet, and the products are transported from the origin to the destination in pallet units. When transporting one pallet's worth of products (transport lot), operations 1 to 5 shown in Figure 6 occur for each transport lot. Of these, operations 1, 3, and 5 are performed by the transport vehicle. For a single transport lot, operations 1, 3, and 5 corresponding to that lot do not all have to be performed by the same transport vehicle; each operation can be performed by a different transport vehicle. An example of a transport work schedule is shown in Figure 7. In the transport work schedule shown in Figure 7, one record stores the movement work from one departure location to one arrival location. In the "Operation Type" field, "Single Travel" refers to travel by the towing unit alone without a pallet loaded, "Empty Pallet Transport" refers to travel by transporting a pallet without a transport lot loaded (corresponding to operations 1 and 5 in Figure 6), and "Transport Lot Transport" refers to travel by a pallet loaded with a transport lot (corresponding to operation 3 in Figure 6). The pallet ID is assigned by selecting the record of the pallet type specified in the transport lot record (Fig. 4).

[0046] [Work allocation rules] Next, an example of a work allocation rule will be described with reference to FIGS.

[0047] Unlike a work schedule, work allocation rules do not determine in advance which equipment will perform a task; instead, they determine which equipment to allocate tasks to based on factors such as priority and the situation at the time the simulation is run. Here, we will explain an example of using work allocation rules to determine which pallets to load transport lots on. However, when allocating transport lots to transport vehicles, it is assumed that the transport lots to be handled by each transport vehicle, the work order, and the desired transport start time are determined in advance as part of a transport work schedule, as shown in Figure 8. It is also assumed that the pallets currently available to each transport vehicle are determined as shown in the list in Figure 9. Pallets included in the list in Figure 9 cannot be used (transported) by any vehicle other than the one assigned to them, but this list information is updated during the simulation based on the work allocation rules, so available pallets change as needed. An example of a work allocation rule related to pallets is shown below.

[0048] (1) Pallet shortage determination rules (2) Pallet selection rules for transport lot allocation (3) Rules for releasing unnecessary pallets

[0049] The pallet shortage determination rule (1) is a rule that adds usable pallets when there are not enough usable pallets in each transport vehicle. The pallet shortage determination rule collects transport lot information (FIG. 8) assigned to each transport vehicle and executes the processing of steps S11 and S12 below.

[0050] Step S11: On the condition that an empty pallet for loading the target transport lot has not been brought into the transport source of the target transport lot, the earliest operation in the operation sequence that satisfies the following conditions is extracted from the transport lot.

[0051] Step S12: If pallets of the pallet type corresponding to the extracted transport lot have been assigned to the target transport vehicle (Fig. 9), and the next transport lot to be loaded on at least one of those pallets has not yet been determined, the rule processing is terminated as there is no pallet shortage. Otherwise, the rule processing is terminated as there is a pallet shortage (the pallet type corresponding to the extracted transport lot in the previous step is designated as the "missing pallet type").

[0052] The transport lot allocation pallet selection rule (2) is a rule for allocating pallets to the transport lot extracted in step S11 above. If the pallet shortage determination rule determines that there is a pallet shortage, the pallet that is closest to the current position of the transport vehicle is selected from among the pallets of the corresponding pallet type that are not available to any transport vehicle. On the other hand, if the pallet shortage determination rule does not determine that there is a pallet shortage, the pallet that has finished unloading the transport lot the earliest from among the pallets available to the target transport vehicle is selected.

[0053] The rule for releasing unnecessary pallets (3) sets an upper limit on the number of pallets that each transport vehicle can use, and if both of the following conditions 1 and 2 are met, the pallet that has finished unloading the transport lot the earliest is removed from the list of available pallets.

[0054] Condition 1: The number of pallets that the target transport vehicle can use is the upper limit. Condition 2: The pallet shortage judgment rule determines that there is a pallet shortage.

[0055] By using such work allocation rules, it is possible to configure a logistics simulation device with less effort than with work scheduling. Note that for work allocation processes that satisfy the following conditions in actual operations, a logistics simulation device that implements the same processes as in actual operations can be configured.

[0056] - A computer program is used to create a work assignment plan, or the work assignment plan is created manually, but the procedure is clearly defined (applies to work schedules) - Work is assigned automatically by operational rules, or by manual operation with clearly defined operational rules (work assignment rules are applied)

[0057] [Procedure for determining the work allocation method] Regarding the task allocation method, when detailed criteria for task scheduling and task allocation rules are not defined, it becomes difficult to perform task allocation processing using the above-mentioned approach. In this embodiment, a method for determining whether to use a task schedule or task allocation rules when allocating transport vehicles to pallet transport tasks and allocating transport lots to pallets is described. The following three indices are used in this determination.

[0058] Index 1: Number of combinations of work assignments to each facility Index 2: Work efficiency distribution information for each combination of work assignments to each facility that satisfies the constraints when simultaneously assigning multiple facilities to one task Indicator 3: Distribution information of the time required for a piece of equipment to complete a task when that task is assigned to that equipment

[0059] [Calculation method for indicator 1] The calculation method for index 1 when allocating pallet transport work to transport vehicles is explained below. Now, let us assume that the total number of transported lots is N l , the total number of transport vehicles is n v In this case, there are three types of work that a transport vehicle performs per transport lot (see Figure 6), so the number of tasks that a transport vehicle is responsible for is 3N l And, the number of combinations that can allocate all transport vehicles without any constraints is 3N l n vTherefore, this can be used as index 1. The data required for the calculation can be obtained from the facility information DB 100a, the cargo information DB 100b, and the work information DB 100c. Note that the number of combinations can be reduced to index 1 by setting a minimum number of tasks that can be assigned to one vehicle or by adding various operational constraints. If the allocation of transport vehicles is not completely free and the following constraints are imposed, the number of work allocation combinations will be smaller. These constraints can be specified by the work allocation constraint information for equipment in the facility information DB in the information storage device 100. For example, suppose the following constraints are present for the allocation of transport vehicles:

[0060] · Routes of transport lots (from source to destination) are grouped, and the same transport vehicle is responsible for transporting the transport lots of the same group (number of groups: N g ). The transport vehicle in charge of transporting empty pallets (tasks 1 and 5) is the same as the transport vehicle in charge of the corresponding transport task (task 3).

[0061] In this case, the number of combinations is N g n v The number of combinations will be even smaller if an upper limit is set on the number of groups that one transport vehicle is responsible for. Note that if the number of combinations is so large that it is not possible to calculate the number of combinations accurately, it is possible to set index 1 by calculating the number of combinations approximately. If index 1 is large, this means that there are many combinations of work assignments, which increases the burden of creating a computer program that creates a work schedule. Therefore, if there is not enough time to develop such a program, adopting a work assignment rule will enable the construction of a more realistic logistics simulation device.

[0062] [Calculation method for indicator 2] For example, in task 3 shown in Figure 6, a pallet to load the transport lot and a transport vehicle to move each pallet are assigned to the transport lot. The following explains how to calculate index 2 when the following constraints exist regarding the allocation of this heterogeneous equipment (pallets, transport vehicles).

[0063] [Allocation Constraints] The pair of transport vehicle and pallet specified for each time period will be responsible for the same transport lot. An example of allocation constraints is shown below. For example, for the i-th time period, starting time: 2022 / 8 / 3 7:00~end time: 2022 / 8 / 3 12:00, the pair of transport vehicle and pallet is set as shown below.

[0064] (1) Transport vehicle 1: Pallet AK001, Pallet AK002, Pallet AK005, Pallet BK001, Pallet BK002 (2) Transport vehicle 2: Pallet AK003, Pallet AK004, Pallet AK006, Pallet BK003, Pallet BK004 (3) Transport vehicle 3: Pallet AK007, Pallet AK008, Pallet AK009, Pallet BK005, Pallet BK006

[0065] In this case, for example, when transport lot NN10017 is assigned to transport vehicle 2 in the ith time slot, if the pallet type for loading transport lot NN10017 is limited to AK, then one of pallets AK003, AK004, or AK006 must be selected (group (2) will be selected). When calculating index 2, the impact of changing the assigned pallet to pallet AK003, AK004, or AK006 is quantified. The process can be summarized as follows:

[0066] (1) Data on the transport lots to be transported during a certain time period is generated based on past performance data, etc. (2) Generate a large number of combinations of these transport lots and vehicles. (3) For the combinations assigned in (2), further combinations of pallets to load each transport lot are generated.

[0067] The calculation flow will be explained using a specific example. First, 50 transport lots are generated, and combinations are generated by allocating these to three transport vehicles (transport vehicle 1 to transport vehicle 3). When generating these combinations, all possible combinations may be generated, or only combinations that have actually been allocated in the past may be generated. Then, combinations are generated in which the pallets responsible for the 50 transport lots allocated to the transport vehicles are allocated to pallets that satisfy the allocation constraints above. For each combination, combinations in which a large number of tasks are allocated disproportionately to a small number of pallets may be excluded.

[0068] Then, the work efficiency is calculated for all the above combinations. Values ​​such as "makespan" are used as an indicator of work efficiency. Makespan refers to the time from the start of transport of the earliest transported lot to the end of transport of the latest transported lot. Makespan refers to the total time it takes to complete all work, and if work assignments are sufficiently leveled, the makespan value will be small. Conversely, if work is concentrated on a certain piece of equipment, the work completion time of the equipment where the work is concentrated will be delayed, and the makespan value will be large. An estimated makespan value is calculated for each combination using a computer program, etc., and the efficiency value for each combination is calculated according to the formula below.

[0069]

number

[0070] For the combination with the smallest makespan, the efficiency value is 100 (maximum value). Next, an efficiency value record is created for each combination, and the records are sorted in descending order (see FIG. 10). Then, from all the records, the record that is the set value (20%, 40%, 60% in this embodiment) is selected, and the efficiency value of that record is obtained. If the total number of records (all combinations) is 100, the 20th, 40th, and 60th efficiency values ​​from the top are obtained and set as the set value 2.

[0071] When using this setting value 2, if the 20th, 40th, and 60th values ​​are small relative to the maximum value (100), this means that work efficiency will drop sharply if the work assignment differs from the optimal work assignment (number 1). When using work assignment rules, the work assignment is often not necessarily optimal. For this reason, in such situations, the work efficiency executed in the simulation may deviate significantly from actual operations and become poor, so it is better to use a work schedule when assigning work. Conversely, if the 20th, 40th, and 60th values ​​are not too far from 100, work efficiency will not decrease even if the work assignment differs slightly from the optimal work assignment (number 1), so there is little chance of work efficiency decreasing even when using work assignment rules.

[0072] [Calculation method for indicator 3] When tasks are assigned to transport vehicles, the time required to complete tasks 1, 3, and 5 in Figure 6 is calculated based on performance data, etc., to generate distribution information, and the generated distribution information is used as index 3. For example, the following values ​​can be used as the distribution information.

[0073] Average time required to complete a task The maximum constant τ1 that makes the number of actual records that satisfy the task completion time ≦ τ1 less than 25% of the total number of records The maximum constant τ2 that makes the number of actual records that satisfy the task completion time ≦ τ2 75% or less of the total number of records

[0074] When index 3 is a small value, work can be completed with a small number of pieces of equipment. On the other hand, when index 3 is a large value, a large number of pieces of equipment are required, and large-scale calculations are necessary when allocating work. Generally, large-scale calculations require complex work schedule creation programs. For this reason, when there is not enough man-hours to set up a logistics simulation device, work allocation rules are used to simplify the process.

[0075] Once the calculation of indicators 1 to 3 is completed as described above, a function is set using indicators 1 to 3 as variables as shown in the following formula (2). If the value of the function is equal to or greater than the set value, work scheduling is applied in the work allocation of the simulation program, and if the value of the function is less than the set value, a work allocation rule is applied in the work allocation of the simulation program.

[0076]

number

[0077] The variables in the above formula (2) have the following meanings: Although there are seven variables in formula (2), the number of variables is not limited to this.

[0078] X: Index 1 Y 20 :Efficiency value of the 20th record of index 2 Y 40 :Efficiency value of the 40th record of index 2 Y 60 :Efficiency value of the 60th record of index 2 Z1: Average time required to complete the task for index 3 Z2: The maximum constant τ1 such that the number of actual records that satisfy the required time for completing the task in index 3 ≦ τ1 is 25% or less of the total number of records. Z3: The maximum constant τ2 for which the number of actual records that satisfy the required time for completing the task for index 3 ≦ τ2 is 75% or less of the total number of records.

[0079] The function F may be expressed as a linear expression of variables, or may be defined as a nonlinear function.Furthermore, the function F may be defined using a rule with an if statement, as shown in the following formulas (3) and (4).

[0080]

number

[0081]

number

[0082] In formulas (3) and (4), p k ,q k (k=1,…,6) and r k (k=1, 2) are the parameters and constant terms multiplied by each indicator variable, respectively.

[0083] By using such criteria, it is possible to determine whether to use a work schedule or a work allocation rule when allocating work to each facility in a logistics simulation, thereby enabling the construction of a logistics simulation device with the minimum necessary load.

[0084] [Configuration of the configuration decision support device] Fig. 11 is a block diagram showing the configuration of a configuration determination support device for a logistics simulation device, which is one embodiment of the present invention. As shown in Fig. 11, configuration determination support device 200 for a logistics simulation device, which is one embodiment of the present invention, is configured by an information processing device such as a personal computer, and includes an information storage unit 201, an index calculation unit 202, a configuration determination unit 203, and an output unit 204. The functions of index calculation unit 202, configuration determination unit 203, and output unit 204 are realized by an arithmetic processing unit within the information processing device executing a computer program.

[0085] The information storage unit 201 is configured with a nonvolatile storage device such as a ROM, and stores a facility information DB 201a, a package information DB 201b, and a work information DB 201c. The facility information DB 201a, package information DB 201b, and work information DB 201c store the same types of data as the data stored in the facility information DB 100a, package information DB 100b, and work information DB 100c shown in Fig. 3. The facility information DB 100a, package information DB 100b, and work information DB 100c shown in Fig. 3 may be shared.

[0086] The index calculation unit 202 calculates the above indexes 1 to 3 using the performance data stored in the equipment information DB 201a, the baggage information DB 201b, and the work information DB 201c, and outputs information on the calculated indexes 1 to 3 to the configuration determination unit 203.

[0087] The configuration determination unit 203 calculates the value of the function F by substituting the indicators 1 to 3 calculated by the indicator calculation unit 202 into the function F, which has the indicators 1 to 3 as variables. If the value of the function F is equal to or greater than a set value, the configuration determination unit 203 determines to apply work scheduling in the work allocation of the simulation program. On the other hand, if the value of the function F is less than the set value, the configuration determination unit 203 determines to apply a work allocation rule in the work allocation of the simulation program.

[0088] The output unit 204 outputs information indicating the results determined by the configuration determination unit 203. Thereafter, the operator configures the logistics simulation device in accordance with the information output from the output unit 204. This makes it possible to configure the logistics simulation device with the minimum necessary load.

[0089] Although the present invention has been described above as an embodiment, the present invention is not limited to the descriptions and drawings that form part of the disclosure of the present invention. In other words, other embodiments, examples, and operational techniques that can be made by those skilled in the art based on the present invention are all included in the scope of the present invention. [Explanation of symbols]

[0090] 1 Logistics equipment 2 overhead crane 3. Loading Crane 4 Transport vehicles 4a Traction section 4b Palette 5a~5c Product warehouse 6. Carrier 7 Vehicle loading and unloading entrance 100 Information storage device 100a Facility Information Database (Facility Information DB) 100b Baggage Information Database (Baggage Information DB) 100c Work Information Database (Work Information DB) 101 Transport vehicle communication device 102 Ceiling crane communication device 103 Loading crane communication device 104 Input section 104a Simulation condition input section 104b Rule input section 105 Work generation section 106 Simulation Plan Generation Unit 107 Simulation Department 108 Simulation information output section 200 Logistics simulation device configuration decision support device 201 Information Storage Department 202 Indicator calculation section 203 Configuration Determination Department 204 Output section C coil

Claims

1. A configuration decision support method for a logistics simulation device that visualizes, on a computer, the state of each piece of equipment in a logistics facility that includes equipment for transporting goods, equipment for storing goods, and equipment for transferring goods, comprising: an index calculation step of calculating an index taking into consideration at least one of a combination of work assignments to each facility, work efficiency determined by the work assignments to each facility, and work completion time determined by the work assignments to each facility, using information about the cargo to be moved; a determination step of determining whether to allocate work to each piece of equipment according to a work allocation rule that determines the next work that each piece of equipment will perform based on the index calculated in the index calculation step, or according to a work schedule that specifies the equipment in charge of each work and the time or order in which each work will be performed; an output step of outputting a result of the determination step; A method for supporting determination of a configuration of a logistics simulation device, comprising:

2. 2. The method for supporting determination of a configuration for a logistics simulation device according to claim 1, wherein the index calculation step calculates at least one index from the number of combinations of task assignments to each piece of equipment, the work efficiency distribution for each combination of task assignments to each piece of equipment that satisfies constraints when simultaneously assigning a plurality of pieces of equipment to one task, and the distribution of time required for a piece of equipment to complete a task when the task is assigned to the equipment.

3. 2. The method for supporting determination of a configuration for a logistics simulation device according to claim 1, wherein the determination step includes a step of calculating a unified evaluation value that enables determination of whether it is better to select the work assignment rule or the work schedule, and selecting the work assignment rule or the work schedule in accordance with a threshold value of the evaluation value.

4. The configuration determination support method for a logistics simulation device according to any one of claims 1 to 3, wherein the equipment for transporting the cargo is a transport vehicle whose towing unit and pallet can be separated, and the index calculation step and the determination step are executed when determining a method for allocating transport vehicles to pallet transport work and a method for allocating transport lots to pallets.

5. A configuration decision support device for a logistics simulation device that visualizes on a computer the state of each facility in a logistics facility that includes facilities for transporting luggage, facilities for storing luggage, and facilities for transferring luggage, comprising: an index calculation means for calculating an index taking into consideration at least one of a combination of work assignments to each facility, work efficiency determined by the work assignments to each facility, and work completion time determined by the work assignments to each facility, using information about the cargo to be moved; a determination means for determining whether to allocate work to each piece of equipment in accordance with a work allocation rule that determines the next work that each piece of equipment will perform based on the index calculated by the index calculation means, or a work schedule that specifies the equipment in charge of each work and the time or order in which each work will be performed; an output means for outputting the determination result of the determination means; A configuration decision support device for a logistics simulation device, comprising:

6. 6. The configuration determination support device for a logistics simulation device according to claim 5, wherein the index calculation means calculates at least one index from the number of combinations of task assignments to each piece of equipment, the work efficiency distribution for each combination of task assignments to each piece of equipment that satisfies constraints when simultaneously assigning a plurality of pieces of equipment to one task, and the distribution of time required for a piece of equipment to complete a task when the task is assigned to the equipment.

7. 6. The configuration determination support device for a logistics simulation device according to claim 5, wherein the determination means calculates a unified evaluation value that can determine whether it is better to select the work allocation rule or the work schedule, and selects the work allocation rule or the work schedule according to a threshold value of the evaluation value.

8. The configuration determination support device for a logistics simulation device according to any one of claims 5 to 7, wherein the equipment for transporting cargo is a transport vehicle whose towing unit and pallet can be separated, and the index calculation means and the determination means execute processing when determining a method for allocating transport vehicles to pallet transport work and a method for allocating transport lots to pallets.

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