Transportation planning system, transportation planning method, and program

Abstract

To sufficiently suppress computation time required for a conveyance plan.SOLUTION: A conveyance plan system comprises: conveyance request grouping means which respectively characterizes a plurality of conveyance requests including information on a set of a starting point node, which receives a package, and an ending point node, which shows a point to deliver the received package, using at least one of (a) both of the distantly positioned conveyance requests are an amount which becomes a distant value, and (b) both of the conveyance requests where conveyance paths of a plurality of carrier machines overlap are an amount which becomes a close value based on conveyance path information, which is information on a travel path including a plurality of nodes and edges and where the carrier machines travel, and groups the conveyance requests based on the characterized amount in response to the conveyance requests; conveyance request allocation means which allocates a set of the grouped conveyance requests to the respective carrier machines; and carrier machine route planning means which plans travel of the respective carrier machines so that collision between the respective carrier machines does not occur based on a set of the conveyance requests allocated to the respective carrier machines.SELECTED DRAWING: Figure 2

Description

[Technical field]

[0001] The present invention relates to a transportation planning system, a transportation planning method, and a program for planning transportation by a transportation machine. [Background technology]

[0002] When the number of nodes and edges that represent the transportation requirements, number of conveyors, and travel routes when transporting luggage and the like increases, the number of combinations increases explosively. This causes a problem that the calculation time required for optimal transportation planning becomes enormous. In response to this, a transportation planning system that uses a genetic algorithm to plan optimal transportation for each conveyor is known (for example, see Patent Document 1). [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2001-209430 A Summary of the Invention [Problem to be solved by the invention]

[0004] However, since the genetic algorithm searches for a solution by chance, even if the same transportation request is made, the transportation planning system may plan different transportation. Therefore, the calculation time required for the optimal transportation plan varies, and there is a risk that the calculation time cannot be sufficiently controlled.

[0005] The present invention has been made to solve the above problems, and a main object of the present invention is to provide a transportation planning system, a transportation planning method, and a program that can sufficiently reduce the calculation time required for a transportation plan. [Means for solving the problem]

[0006] In order to achieve the above object, one aspect of the present invention is to a transport request grouping means for characterizing a plurality of transport requests, each of which includes information on a pair of a start node where each transport device receives luggage and an end node that represents a location where each transport device delivers the luggage it has received, based on transport path information, which includes a plurality of nodes and edges and is information on paths along which a plurality of transport devices travel, using at least one of (a) an amount by which transport requests located at distant locations have different values, and (b) an amount by which transport requests whose transport paths overlap have similar values, and for grouping the transport requests based on the amount characterizing the transport requests; a transport request allocation means for allocating the groups of transport requests grouped by the transport request grouping means to each transport machine; a transport vehicle route planning means for planning the travel of each transport vehicle based on the set of transport requests assigned to each transport vehicle by the transport request assignment means so as to prevent collisions between the transport vehicles; A transportation planning system comprising: It is. In this one aspect, the transport request grouping means may characterize each of the multiple transport requests using (a) the amount by which transport requests located at distant locations have different values, and (b) the amount by which transport requests whose transport paths of the transport machines overlap have similar values. In this aspect, the transport request grouping means may, in response to the amount by which (a) transport requests located at distant locations become different in value, (a1) introduce the coordinates of the midpoint of a line connecting a start node and an end node of the transport request, and in response to the amount by which (b) transport requests whose transport paths of the transport machine overlap become close in value, (b1) weight nodes on the transport path from the start node to the end node in the transport request based on the number of transport paths that pass through the node, and introduce a value obtained by summing up the weights along the transport path. In this one aspect, the transport request grouping means may group the transport requests by clustering the transport requests based on the amount characterizing the transport requests so that the workload of each group of transport requests is equal to or less than a predetermined amount. In this one aspect, the transport request allocation means allocates groups of transport requests from the groups of transport requests grouped by the transport request grouping means in order from the transport vehicle with the earliest end time of the previous transport plan, and may assign to each transport vehicle the set of transport requests that is closest to the end point of the transport plan for that transport vehicle. In this one aspect, the conveyor route planning means may determine, as the conveyor travel route, a route that connects the shortest routes from the start node to the end node of each conveyor request included in the group of conveyor requests grouped by the conveyor request grouping means, in a predetermined order of processing the conveyor requests. In this one aspect, the conveying machine path planning means may combine Petri nets for the determined travel paths of all the conveying machines to create a Petri net for the entire conveying machine, and apply a predetermined token rule to the created Petri net for the entire conveying machine, thereby planning the travel timing of each conveying machine so as to prevent collisions between the conveying machines. In order to achieve the above object, one aspect of the present invention is to A step of characterizing a plurality of transport requests, each of which includes information on a pair of a start node where each transport device receives luggage and an end node representing a location where each transport device delivers the luggage, based on transport path information, which includes a plurality of nodes and edges and is information on the travel paths along which a plurality of transport devices travel, using at least one of (a) an amount by which transport requests located at distant locations have different values, and (b) an amount by which transport requests whose transport paths overlap have similar values, and grouping the transport requests based on the amount characterizing the transport requests; Allocating the grouped sets of transport requests to each transport device; A step of planning travel of each of the transport vehicles based on the set of transport requests assigned to each of the transport vehicles so that collisions between the transport vehicles do not occur; Transportation planning method including may be also possible. In order to achieve the above object, one aspect of the present invention is to A process of characterizing a plurality of transport requests, each of which includes information on a pair of a start node where each transport device receives luggage and an end node that represents a location where each transport device delivers the luggage, based on transport path information, which includes a plurality of nodes and edges and is information on the travel paths along which a plurality of transport devices travel, using at least one of (a) an amount by which transport requests located at distant locations have different values, and (b) an amount by which transport requests whose transport paths overlap have similar values, and grouping the transport requests based on the amount characterizing the transport requests; A process of allocating the grouped sets of transport requests to each transport device; A process of planning the travel of each of the transport vehicles based on the set of transport requests assigned to each of the transport vehicles so that collisions between the transport vehicles do not occur; A program that causes a computer to execute may be also possible. Effect of the Invention

[0007] According to the present invention, it is possible to provide a transportation planning system, a transportation planning method, and a program that can sufficiently reduce the calculation time required for a transportation plan. [Brief description of the drawings]

[0008] [Figure 1] 1 is a block diagram showing a schematic system configuration of a transportation planning system according to an embodiment of the present invention. [Diagram 2] 1 is a block diagram showing a schematic configuration of a transportation planning apparatus according to an embodiment of the present invention. [Diagram 3] FIG. 13 is a diagram showing an example of a lattice-shaped travel path and a transport request. [Figure 4] 10 is a flowchart showing a flow of a method for grouping transport requests by clustering according to the present embodiment. [Diagram 5] 10 is a flowchart showing a specific flow of an allocation method for allocating a set of transport requests to each transport machine. [Figure 6] 2 is a block diagram showing a schematic system configuration of a transport vehicle path planning unit according to the present embodiment. FIG. [Figure 7] 10 is a flowchart showing a flow for determining an order in which transport requests are processed; [Figure 8] FIG. 11 is a diagram for specifically explaining a method for determining a driving route. [Figure 9] FIG. 2 is a diagram showing a travel route excluding an end node and an arrow from the end node. [Figure 10] FIG. 13 is a diagram showing a Petri net representing a travel path with the circles and bars of the travel path labeled, and the movement of a transport vehicle along the travel path. [Figure 11] This diagram shows an arrow connecting the place of the start node of a transportation request and a transition representing a movement from the start node. [Figure 12] This diagram shows an arrow connecting the place of the end node of a transportation request and a transition representing a movement from the end node. [Figure 13] FIG. 13 is a diagram illustrating a connection when the end node of a transport request and the start node of the next transport request are the same. [Figure 14] FIG. 13 is a diagram showing a case where a Petri net for delivery is added to all transportation requests. [Figure 15] FIG. 13 is a diagram showing a Petri net for delivery of a transport request to an end node; [Figure 16] FIG. 13 is a diagram showing a Petri net of a travel path. [Figure 17] FIG. 1 is a diagram showing a case where two conveyors A and B are on a traveling path. [Figure 18] FIG. 2 is a diagram showing Petri nets for conveyors A and B. [Figure 19] This is a diagram showing the Petri nets of transport machines A and B combined with a resource place pres,n. [Figure 20] FIG. 13 is a diagram for explaining rules for token movement. [Figure 21] 4 is a flowchart showing a flow of a transportation planning method according to the present embodiment. [Figure 22] FIG. 11 is a block diagram showing a configuration of a transportation planning system that does not include a transportation planning device. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0009] EMBODIMENT 1 Hereinafter, an embodiment of the present invention will be described with reference to the drawings. The transportation planning system according to the present embodiment assigns transportation requests, including information on the pick-up and delivery points of the luggage transported by the transport vehicles, to a plurality of transport vehicles running on a travel route, and determines the transportation route of each transport vehicle based on the assignment of the transportation requests. In addition, the transportation planning system according to the present embodiment obtains a quantity that represents the characteristics of the transportation requests, groups the transportation requests into small units based on the quantity, and assigns the groups of transportation requests to the transport vehicles to determine the transportation route.

[0010] This makes it possible to suppress an increase in the number of nodes and edges representing the transport vehicle's travel path, and an increase in the number of combinations, thereby significantly reducing the calculation time required to create an optimal transport plan.

[0011] 1 is a block diagram showing a schematic system configuration of a transport planning system according to the present embodiment. The transport planning system 1 according to the present embodiment includes a plurality of transport vehicles 2 and a transport planning device 3 that performs transport planning for each of the transport vehicles 2.

[0012] The multiple transport machines 2 and the transport planning device 3 are communicatively connected to each other via a wireless communication network 4, such as a local area network (LAN) or a wide area network (WAN).

[0013] The conveying machine 2 is configured as a conveying robot that has a plurality of sensors such as distance sensors and can move autonomously based on information from each sensor to convey luggage and the like.

[0014] The transportation planning device 3 plans the travel order, travel route, travel timing, etc. of each of the transport vehicles 2 when the transport vehicles 2 transport luggage. The transportation planning device 3 has a hardware configuration of a normal computer including, for example, a processor 11 such as a CPU (Central Processing Unit) or a GPU (Graphics Processing Unit), an internal memory 12 such as a RAM (Random Access Memory) or a ROM (Read Only Memory), a storage device 13 such as an HDD (Hard Disk Drive) or an SDD (Solid State Drive), an input / output I / F 14 for connecting peripheral devices such as a display, and a communication I / F 15 for communicating with devices outside the device.

[0015] 2 is a block diagram showing a schematic configuration of a transport planning device according to this embodiment. The transport planning device 3 according to this embodiment includes a transport path information storage unit 31, a transport vehicle information storage unit 32, a transport request grouping unit 33, a transport request allocation unit 34, and a transport vehicle route planning unit 35.

[0016] The transport path information storage unit 31 stores transport path information of the transport device 2. The transport path information is information on a travel path on which the transport device 2 can move. The travel path is configured as a grid-like graph including a plurality of nodes and edges. The transport path information is set in advance in the transport path information storage unit 31.

[0017] The conveyance unit information storage unit 32 stores the conveyance unit information. The conveyance unit information includes a node indicating the current location of the conveyance unit 2 and a transportation plan for the conveyance unit 2 to perform transportation. The conveyance unit information is transmitted from each conveyance unit 2 and stored in the conveyance unit information storage unit 32.

[0018] The transport path information storage unit 31 and the transport machine information storage unit 32 are configured, for example, by the internal memory 12 and the storage device 13. The transport path information storage unit 31 and the transport machine information storage unit 32 are configured as separate entities, but are not limited to this and may be configured as an integrated entity.

[0019] The transport request grouping unit 33 groups a plurality of transport requests based on the transport route information stored in the transport route information storage unit 31. A transport request is information including a start node where the transport unit 2 receives the luggage and an end node indicating a location where the transport unit 2 delivers the luggage it has received. A transport request is generated, for example, by a server or a user that issues a transport instruction, and input to the transport request grouping unit 33. The transport request may be set in advance in the transport route information storage unit 31, the transport unit information storage unit 32, the transport request grouping unit 33, or the like.

[0020] The transport request allocation unit 34 allocates the sets of transport requests grouped by the transport request grouping unit 33 to each transport vehicle 2. The transport vehicle path planning unit 35 plans transport for each transport vehicle 2 based on the transport requests allocated to each transport vehicle 2 by the transport request allocation unit 34 so as to prevent collisions between the transport vehicles 2.

[0021] Next, the above-mentioned transport request grouping unit 33, transport request allocation unit 34, and transport vehicle path planning unit 35 will each be described in detail.

[0022] [Transportation request grouping part] First, a method for grouping transport requests by the transport request grouping unit 33 will be described. The transport request grouping unit 33 groups a plurality of transport requests based on the following basic grouping concepts (i) and (ii).

[0023] (i) In order to prevent the travel distance of the conveyor 2 from becoming too long, conveyance requests located far away from each other are grouped into different pairs as much as possible. (ii) In order to reduce the possibility of congestion of the conveyor 2, transfer requests with overlapping transfer paths are grouped into the same pair as much as possible. For this reason, the transportation request grouping unit 33 (a) The amount by which transport requests at distant locations have different values ​​(corresponding to (i)), and (b) The amount of transport requests whose transport paths of the transport device 2 overlap each other that are close to each other (corresponding to (ii)), We use the following to characterize each of the transport requests: In this way, by characterizing each transportation request using the two quantities (a) and (b), it is possible to reduce congestion of the transportation device 2 while shortening the travel distance of the transportation device 2, thereby improving transportation efficiency.

[0024] The transport request grouping unit 33 performs clustering so that the workload of each group of transport requests, which are grouped based on the amount characterized by the transport requests, is equal to or less than a predetermined amount, thereby performing grouping of the transport requests. The transport request grouping unit 33 performs clustering to integrate similar transport requests as the same among a plurality of transport requests, thereby performing grouping of the transport requests. The transport request grouping unit 33 uses, for example, a mean shift method as the clustering process.

[0025] By grouping the transport requests as described above, the number of combinations of transport requests can be reduced, and the calculation time required for the transport plan can be reduced. Furthermore, by clustering the transport requests so that the workload of each group is equal to or less than a predetermined amount, and by determining the upper limit of the workload per group of transport requests, it becomes possible to easily estimate the workload of the transport requests.

[0026] As an example of a specific quantity that satisfies (a) above, (a1) the coordinates (x, y) of the midpoint of the line connecting the start node and end node of the transport request are introduced. Also, as an example of a specific quantity that satisfies (b) above, (b1) weighting the nodes on the transport path from the start node to the end node in the transport request based on the number of transport paths that pass through the node, and introducing a value w that sums up these weights along the transport path. The set of these quantities (x, y, w) is the quantity that characterizes the transport request.

[0027] The amount w indicating the degree of overlap of the transport requests (hereinafter, overlap degree) in (b1) above will be described in more detail using the example of transport requests shown in Fig. 3. Fig. 3 is a diagram showing an example of a lattice-shaped travel path and transport requests. A transport request is given as a pair (O, D) where O represents the start node of the transport and D represents the end node of the transport. In Fig. 3, five transport requests are given: (O1, D1), (O2, D2), (O3, D3), (O4, D4), and (O5, D5).

[0028] The transport request grouping unit 33 calculates the overlapping degree w of the above five transport requests by the following (1) to (3).

[0029] (1) The transport request grouping unit 33 finds a representative shortest route for each of the five transport requests (O1, D1), (O2, D2), (O3, D3), (O4, D4), and (O5, D5). Hereinafter, this shortest route for the transport requests is referred to as a representative route. In FIG. 3, dotted and dashed lines other than the solid lines indicate the representative routes for each transport request that were actually found. Note that, if there are multiple shortest routes, the transport request grouping unit 33 arbitrarily selects one of the multiple shortest routes.

[0030] (2) Based on the determined representative route, the transportation request grouping unit 33 sets the weight of the node to a value obtained by subtracting 1 from the number of representative routes that pass through the node. However, as shown in FIG. 3, the weight of a node that does not have even one representative route is set to 0.

[0031] For example, node D3 is passed through by the representative routes of three transport requests (O1, D1), (O2, D2), and (O3, D3). Therefore, the node weight of D3 is 2, which is the number of representative routes that pass through node D3 minus 1.

[0032] (3) The transportation request grouping unit 33 calculates the sum of the weights of the nodes included in the representative route of each transportation request as the degree of overlap w of each transportation request.

[0033] In the case of Figure 3, the overlapping degree of the five transport requests (O1, D1), (O2, D2), (O3, D3), (O4, D4), and (O5, D5) is w (O1、D1) =6, w (O2、D2) =5, w (O3、D3) =3, w (O6、D6) =1, w (O5、D5) =1.

[0034] Next, a method of grouping transport requests by clustering using the quantities (x, y, w) characterizing the transport requests described above will be described with a specific example.

[0035] First, when clustering the transport requests, an upper limit value of the size of grouping per group is set. The upper limit value is, for example, an upper limit of the total value of the representative path lengths of the transport requests included in the grouping, and is an upper limit of the workload per group. The upper limit value may be set in advance in the transport request grouping unit 33, etc.

[0036] FIG. 4 is a flowchart showing the flow of a method for grouping transport requests by clustering according to this embodiment.

[0037] The transport request grouping unit 33 sets all the transport requests as S (step S401). The transport request grouping unit 33 clusters the transport requests in the collection S of transport requests into two groups based on an amount that characterizes the transport requests (step S402).

[0038] The transport request grouping unit 33 calculates the size of each of the two clusters obtained by the clustering and checks whether the size of each cluster is equal to or smaller than the upper limit value set above. The transport request grouping unit 33 records a cluster whose size is equal to or smaller than the upper limit value as OK, and a cluster whose size exceeds the upper limit value as NG (step S403).

[0039] The transport request grouping unit 33 checks whether or not there is an NG cluster in the recorded clusters (step S404). If there is an NG cluster (YES in step S404), the transport request grouping unit 33 extracts one NG cluster, sets the set of transport requests of that cluster to S (step S405), and returns to the above (step S402).

[0040] If there is no NG cluster (NO in step S404), the transport request grouping unit 33 outputs the OK cluster as a group of transport requests to the transport request allocation unit 34, and ends this process (step S406).

[0041] In the above description, the transport request grouping unit 33 characterizes each of the multiple transport requests using (a) the amount by which transport requests located at different positions are different from each other and (b) the amount by which transport requests whose transport paths of the transport machines overlap are close to each other, but is not limited to this. The transport request grouping unit 33 may characterize each of the multiple transport requests using at least one of (a) the amount by which transport requests located at different positions are different from each other and (b) the amount by which transport requests whose transport paths of the transport machines overlap are close to each other.

[0042] For example, when the number of conveyors 2 conveying luggage is small, the conveyance request grouping unit 33 may (a) characterize each of the multiple conveyance requests by using only the amount by which the conveyance requests at distant positions have different values. This simplifies the calculation and further reduces the calculation time required to determine the conveyance plan.

[0043] [Transportation Request Allocation Department] The transport request allocation unit 34 allocates the groups of transport requests grouped by the transport request grouping unit to each transport machine 2. The transport request allocation unit 34 acquires the end times at which all previous transport plans end from the transport machine information of each transport machine 2 stored in the transport machine information storage unit 32. The transport request allocation unit 34 allocates the groups of transport requests in the order starting from the transport machine 2 with the earliest end time of the previous transport plan.

[0044] The transport request allocation unit 34 allocates, to each transport unit 2, a set of transport requests that is closest to the end point of the transport unit 2, based on the transport unit information of each transport unit 2 in the transport unit information storage unit 32. This makes it possible to minimize the travel distance of the transport unit 2 and improve transport efficiency.

[0045] FIG. 5 is a flow chart showing a specific flow of an allocation method for allocating the above-mentioned set of transport requests to each transport machine.

[0046] The transport request allocation unit 34 obtains, from the transport machine information of each transport machine 2 stored in the transport machine information memory unit 32, the node (end node) where each transport machine 2 will be located when all transport plans for each transport machine 2 are completed (step S501).

[0047] The transportation request allocation unit 34 calculates the shortest distance from the end node to the start node of an unallocated transportation request (step S502).

[0048] The transport request allocation unit 34 finds a transport request with the shortest distance from the end node to the start node, and allocates a set of transport requests including the found transport request to the transport device 2 (step S503).

[0049] The transport request allocation unit 34 outputs the results of the set of transport requests allocated to each transport machine 2 to the transport machine path planning unit 35 as described above.

[0050] [Conveyor Path Planning Department] The conveying machine route planning unit 35 determines the order, driving route, and driving timing when each conveying machine 2 processes each transport request of the assigned set of transport requests based on the set of transport requests assigned to each conveying machine 2 by the transport request allocation unit 34.

[0051] 6 is a block diagram showing a schematic system configuration of the conveyor path planning unit according to the present embodiment. The conveyor path planning unit 35 according to the present embodiment includes a process order determination unit 351 that determines the order of conveyance requests, a travel path determination unit 352 that determines the travel path of the conveyor 2, and a travel timing determination unit 353 that determines the travel timing of the conveyor 2.

[0052] [Processing order determination part] The processing order determination unit 351 determines the order in which each transport request is processed among the set of transport requests assigned to each transport machine 2. FIG. 7 is a flowchart showing the flow for determining the order in which each transport request is processed. Note that a number indicating the processing order is set in advance for the assigned transport request. The larger this number, the later the processing order. A transport request for which no number is set is regarded as an undetermined transport request. The processing order determination unit 351 determines the order in which the transport machine 2 processes the undetermined transport requests as follows.

[0053] The processing order determination unit 351 records the largest number among the transport requests whose orders have been determined, and sets the recorded number as k (step S701).

[0054] The processing order determination unit 351 calculates the shortest path length from the end node of the recorded transfer request with the number k to the start nodes of all pending transfer requests, and acquires the pending transfer request with the shortest shortest path length (step S702).

[0055] The processing order determination unit 351 sets the number of the acquired pending transfer request to k+1 (step S703).

[0056] The processing order determination unit 351 checks whether or not there is an undetermined transfer request (step S704). If the processing order determination unit 351 determines that there is an undetermined transfer request (YES in step S704), it records k+1 as k (step S705) and returns to the above processing (step S702). On the other hand, if the processing order determination unit 351 determines that there is no undetermined transfer request (NO in step S704), it ends this processing.

[0057] The processing order determination unit 351 outputs the processing order of each transport request determined as described above to the travel path determination unit 352 .

[0058] [Route determination unit] The travel path determination unit 352 determines a travel path of the conveyor 2 based on the order of processing the conveyance requests determined by the processing order determination unit 351.

[0059] Specifically, the travel route determination unit 352 selects the representative route of the transport request used by the transport request grouping unit 33 as the travel route. After the transport request is completed, the travel route determination unit 352 selects one of the shortest routes as the travel route to the start node of the next transport request. Then, the travel route determination unit 352 determines the route connected in the order of transport request processing as the travel route of the transport device 2. This allows the luggage to be efficiently transported via the shortest route in the set transport request processing order.

[0060] Fig. 8 is a diagram for specifically explaining a method for determining a travel route, Fig. 8(a) is an example of a lattice-shaped travel path, and Fig. 8(b) is an example of a transportation request.

[0061] As shown in Fig. 8(b), the travel route determination unit 352 selects the representative route (8→5→2) for the transfer request No. 2 (O1, D1) and the representative route (6→5→4→1) for the transfer request No. 3 (O2, D2), and after the transfer request No. 2 is completed, selects node 3, which is the shortest route, for the travel route toward the start node of the next transfer request No. 3. Then, as shown in Fig. 8(c), the travel route determination unit 352 determines the route (7→(8→5→2)→3→(6→5→4→1)) that connects these selected nodes from the previous end node 7 in the order of the processing of the transfer requests as the travel route for the transfer device 2.

[0062] The travel path determination unit 352 outputs the travel path of each conveyance machine 2 determined as described above to the travel timing determination unit 353.

[0063] [Drive timing determination section] The travel timing determination unit 353 determines the travel timing of each conveying unit 2 based on the travel route of each conveying unit 2 determined by the travel route determination unit 352 so as to prevent collisions between the conveying units 2 .

[0064] The travel timing determination unit 353 describes the travel routes of each conveyance unit 2 determined by the travel route determination unit 352, for example, using an expression method called a Petri net. The travel timing determination unit 353 combines the Petri nets for the travel routes of all conveyance units 2, and calculates the travel timing of each conveyance unit 2 that does not collide with each other. Note that the travel timing determination unit 353 stores the Petri nets created up to the last time, and is capable of reading them out.

[0065] First, a method for creating a Petri net will be specifically described using the travel path shown in FIG.

[0066] (Step 1) Create a driving route by removing the end node and the arrow from the end node from the driving route shown in FIG. 8(c) (FIG. 9).

[0067] (Step 2) In the travel route shown in Figure 9, replace the node numbers with circles (○) and the arrows (→) with the pair of an arrow and a bar "→ | →". Also, label the circles and bars as follows (Figure 10). Let p be the circle corresponding to node number m in the transportation request with number n. n,m After the transportation request with number n is completed, the circle corresponding to node number k during the movement to the next transportation request is p *n,k The bar corresponding to the movement from node number m to node number m' in the transportation request number n is t n,m,m′ After the transportation request of number n is completed, the bar corresponding to the movement from node number k to k′ during the movement to the next transportation request is called t *n,k,k′ Let us assume that.

[0068] However, if there is a node where the end point of the transportation request with number n and the start point of the next transportation request are the same, the label of the corresponding circle is p′ n,m (m is the node number).

[0069] FIG. 10 shows a Petri net representing a travel path in which the circles and bars of the travel path in FIG. 9 are labeled as above, and the transport device 2 moves along the travel path.

[0070] The circles and bars in Figure 10 are called places and transitions, respectively, and represent the following: p n,m : The state where the transport machine 2 is in node number m while transporting the transport request number n p *n,m : After the transport machine 2 has completed the transport request with number n, it is in node number m while moving to the next transport request. ·t n,i,j : An event in which transport machine 2 moves from node number i to node number j while transporting a transport request with number n ·t *n,i,jAfter the transport machine 2 finishes the transport request with number n, it moves from node number i to node number j until the next transport request.

[0071] The arrows connecting the places and transitions in a Petri net represent the conditions and directions of state changes. For example, the arrows in Figure 10 2,8,5 represents "the state of movement from node number 8 to node number 5 in transportation request number 2."

[0072] (Step 3) A Petri net expressing receipt and delivery of luggage is added to the Petri net shown in Fig. 10. The following will explain the transportation request number 2 as an example.

[0073] First, we introduce the following transitions and places to represent the receipt of cargo for transport request number 2. Let t be the transition that represents the event of receiving a package at the starting node. 2,0 Let p be the place that represents the state where the receipt of the luggage is completed at the starting node. 2,0 Let us assume that.

[0074] Then, the place p of the starting node of the transport request number 2 2、8 and a transition t representing the movement from the starting node. 2,8,5 As shown in FIG. 11, and are connected with an arrow.

[0075] For baggage delivery, similar to the baggage receipt described above, the following places and transitions will be introduced. Let t be the transition that represents the event of receiving a package at the destination node. 2,D Let p be the place that represents the state where the package has been received at the end node. 2,D Let us assume that.

[0076] Then, the destination node of the transport request number 2 is the place p 2、D and a transition t representing the movement from the end node. *2,2,3As shown in Fig. 12(a), the nodes are connected by arrows. However, the transition t *2,2,3 If is not present, they bond as shown in FIG. 12(b).

[0077] As shown in FIG. 13(a), when the end node of the transport request numbered 2 and the start node of the next transport request numbered 3 are the same, that is, node number 2, they are connected as shown in FIG. 13(b).

[0078] If the above-mentioned receiving and handing Petri nets are added to all transportation requests, the result will be as shown in FIG. 14.

[0079] (Step 4) Finally, the Petri net of the transport unit 2 itself is combined with the Petri net of Fig. 13. In the case of the travel route shown in Fig. 8, the Petri net of the transport unit 2 is a Petri net for handing over the end node of the transport request numbered 1 as shown in Fig. 15. Note that in Fig. 15, parts other than those necessary for explanation are omitted for ease of understanding.

[0080] By combining the Petri net of the transport machine 2 shown in Fig. 15 with the Petri net shown in Fig. 14 using the above method (steps 2 and 3), a Petri net of the travel route shown in Fig. 16 is created. Note that some parts are omitted in Fig. 16 for ease of understanding.

[0081] Next, a method for obtaining the travel timing from the Petri net created as described above will be explained for the case where there are two conveyors A and B on the travel path as shown in Fig. 17. Fig. 18 shows the Petri nets of the conveyors A and B in Fig. 17.

[0082] (Step 1) For every node number in Figure 17, assign a corresponding place p res,n (n= 1, 2, . . . , 9). res,n is a place indicating that the node number n is in a state where the transport unit 2 can enter. res means a resource that can receive the transport unit 2. res,nis called a resource place.

[0083] Resource Place res,n Arrows are added to the transitions of the Petri net of each transport vehicle 2 according to the following rules. A transition from node number n to another node to resource place p res,n Add an arrow to Resource Place res,n An arrow is attached to a transition representing movement from a node other than node number n to node number n.

[0084] The Petri net of the transporters A and B shown in FIG. 18 and the resource place p res,n When and are combined, they are combined as shown in FIG. 19.

[0085] (Step 2) For all Petri nets connected as described above, add a black dot token ● to represent the current state.

[0086] This token ● is placed inside a place ○, and the state indicated by the place in which the token is placed represents the current state.

[0087] As shown in FIG. 17, the transport machine A has completed receiving the package at node number 7, so as shown in FIG. 19, the place p A1,7 And, place p A1,0 Similarly, as shown in FIG. 17, since the transporter B is at node number 6, the place p B1,6 A token is placed in the place p res,n A token is also placed on the

[0088] (Step 3) Tokens on the Petri net are moved according to rules. Tokens on a place in a Petri net can be changed according to the following rules. For a transition t, if all places with arrows pointing to t have one or more tokens, remove one token from all places with arrows pointing to t and add one token to all places with arrows pointing from t.

[0089] This is a rule that expresses the transition from the current state to the next state, and by observing the changes in the token, it is possible to simulate the movement of the transport machine 2.

[0090] As an example, transition t in Fig. 19 A1,7,8 As shown in FIG. 20(a), the transition t A1,7,8 Place p with an arrow pointing to A1,0 , p A1,7 , p res,8 Therefore, according to the token movement rules, the position of the token will be as shown in Figure 20(b).

[0091] This means that the current state of Figure 20(a) is ·Transporter A is at node number 7 (p A1,7 ), · The receipt of the package has been completed (p A1,0 ), · It is possible for conveyor 2 to enter node number 8 (p res,8 ) This shows the state of the device (Figure 20(b)). Also, t A1,7,8 The event "Transporter A moves from node number 7 to 8" is possible, and the next state after this event occurs is Transporter A is at node number 8 (p A1,8 ) The state where transporter 2 can enter node number 7 (p res,7 ) (Figure 20(b)).

[0092] The important point is that according to this token change rule, when node number n has carrier 2, resource place p res,ndoes not have a token. Therefore, until the transport unit 2 at node number n moves, another transport unit 2 cannot move to node number n, and collisions between transport units 2 do not occur.

[0093] For example, the resource place p of node number 5 shown in FIG. res,5 It can be seen that no collision will occur between conveyors A and B. Therefore, by applying this rule of token change to the Petri net of all conveyors 2 and recording the token changes, it is possible to determine the travel timing at which conveyors 2 do not collide with each other.

[0094] As described above, the travel timing determination unit 353 combines the Petri nets for the travel routes of all the conveyance units 2 determined by the travel route determination unit 352 to create a Petri net for the entire conveyance units 2. The travel timing determination unit 353 then applies the token rules to the created Petri net for the entire conveyance units 2 to plan the travel timing of each conveyance unit so that collisions between the conveyance units do not occur. This allows the Petri net to be used to plan optimal travel timing for each conveyance unit 2 so that collisions between the conveyance units do not occur. The travel timing determination unit 353 may use any method other than the Petri net to plan optimal travel timing for each conveyance unit 2 so that collisions between the conveyance units do not occur.

[0095] Next, the transport planning method according to this embodiment will be described in detail. Fig. 21 is a flowchart showing the flow of the transport planning method according to this embodiment.

[0096] The transport request grouping unit 33 groups a plurality of transport requests based on the transport path information stored in the transport path information storage unit 31, and outputs the grouped requests to the transport request allocation unit 34 (step S211).

[0097] The transport request allocation unit 34 allocates the groups of transport requests grouped by the transport request grouping unit 33 to each transport machine 2 (step S212), and outputs the allocation result to the transport machine path planning unit 35.

[0098] The conveying vehicle path planning unit 35 plans the conveying of each conveying vehicle 2 so that collisions between the conveying vehicles 2 do not occur, based on the set of conveying requests assigned to each conveying vehicle 2 by the conveying request assignment unit 34 (step S213).

[0099] As described above, the transportation planning system 1 of this embodiment 1 is equipped with a transportation request grouping unit 33 that characterizes multiple transportation requests, including information on pairs of a start node where each transportation device 2 receives luggage and an end node representing a location where each transportation device 2 delivers the luggage it has received, based on transportation path information, which includes multiple nodes and edges and is information on the paths along which multiple transportation devices 2 travel, using at least one of (a) an amount by which transportation requests located at different locations have different values, and (b) an amount by which transportation requests whose transportation paths overlap have similar values, and classifies the transportation requests based on the amount characterized for the transportation requests; a transportation request allocation unit 34 that assigns the sets of transportation requests grouped by the transportation request grouping unit 33 to each transportation device 2; and a transportation device path planning unit 35 that plans the travel of each transportation device 2 so as to prevent collisions between the transportation devices 2 based on the sets of transportation requests assigned to each transportation device 2 by the transportation request allocation unit 34.

[0100] According to the transport planning system 1 of the present embodiment 1, the transport requests are characterized using at least one of (a) an amount by which transport requests at distant positions have different values, and (b) an amount by which transport requests whose transport paths of the transport device 2 overlap have similar values, and the transport requests are grouped based on the amount by which the transport requests are characterized. This makes it possible to reduce the number of combinations of transport requests and the calculation time required for the transport plan.

[0101] EMBODIMENT 2 In the above-described transportation planning system 1, the functions provided in the transportation planning device 3 and the transportation machine 2 may be arranged on either device side depending on the use. At least one of the transportation path information storage unit 31, the transportation machine information storage unit 32, the transportation request grouping unit 33, the transportation request allocation unit 34, and the transportation machine path planning unit 35 of the transportation planning device 3 may be arranged on the transportation machine 2 side.

[0102] 22, the transportation planning system 10 may not include the transportation planning device 3. In this case, the transportation machine 30 includes a transportation path information storage unit 31, a transportation machine information storage unit 32, a transportation request grouping unit 33, a transportation request allocation unit 34, and a transportation machine path planning unit 35.

[0103] Although some embodiments of the present invention have been described, these embodiments are presented as examples and are not intended to limit the scope of the invention. These novel embodiments can be implemented in various other forms, and various omissions, substitutions, and modifications can be made without departing from the spirit of the invention. These embodiments and their modifications are included in the scope and spirit of the invention, and are included in the scope of the invention and its equivalents described in the claims.

[0104] The present invention can also be realized by causing a processor to execute a computer program to perform the processing shown in FIG.

[0105] The program can be stored and provided to a computer using various types of non-transitory computer readable media. The non-transitory computer readable media includes various types of tangible storage media. Examples of the non-transitory computer readable media include magnetic recording media (e.g., flexible disks, magnetic tapes, hard disk drives), magneto-optical recording media (e.g., magneto-optical disks), CD-ROMs (Read Only Memory), CD-Rs, CD-R / Ws, and semiconductor memories (e.g., mask ROMs, PROMs (Programmable ROMs), EPROMs (Erasable PROMs), flash ROMs, and RAMs (random access memories)).

[0106] The program may be provided to the computer by various types of transitory computer readable media. Examples of the transitory computer readable medium include an electric signal, an optical signal, and an electromagnetic wave. The transitory computer readable medium can provide the program to the computer via a wired communication path such as an electric wire and an optical fiber, or via a wireless communication path.

[0107] Each unit constituting the transportation planning device 3 according to each of the above-mentioned embodiments can be realized not only by a program, but also in part or in whole by dedicated hardware such as an ASIC (Application Specific Integrated Circuit) or an FPGA (Field-Programmable Gate Array). [Explanation of symbols]

[0108] REFERENCE SIGNS LIST 1 Transportation planning system, 2 Conveyor, 3 Transportation planning device, 4 Wireless communication network, 10 Transportation planning system, 11 Processor, 12 Internal memory, 13 Storage device, 30 Conveyor, 31 Transportation path information storage unit, 32 Conveyor information storage unit, 33 Transportation request grouping unit, 34 Transportation request allocation unit, 35 Conveyor path planning unit, 351 Processing order determination unit, 352 Travel path determination unit, 353 Travel timing determination unit

Claims

1. a transport request grouping means for characterizing a plurality of transport requests, each of which includes information on a pair of a start node where each transport device receives luggage and an end node that represents a location where each transport device delivers the luggage it has received, based on transport path information, which includes a plurality of nodes and edges and is information on paths along which a plurality of transport devices travel, using (a) an amount by which transport requests located at distant positions have different values, and (b) an amount by which transport requests whose transport paths overlap have similar values, and for grouping the transport requests based on the amount by which the transport requests are characterized; a transport request allocation means for allocating the groups of transport requests grouped by the transport request grouping means to each transport machine; a transport vehicle route planning means for planning the travel of each transport vehicle based on the set of transport requests assigned to each transport vehicle by the transport request assignment means so as to prevent collisions between the transport vehicles; Equipped with The transportation request grouping means In response to the amount by which transport requests located at different positions have different values, (a1) introduces coordinates of the midpoint of a line connecting the start node and the end node of the transport request, In response to the amount of overlapping transport requests of the transport machine in the (b) transport path being close to each other, (b1) weighting the nodes on the transport path from the start node to the end node in the transport request based on the number of transport paths passing through the node, and introducing a value obtained by summing the weights along the transport path; based on the amount characterizing the transport requests, the transport requests are grouped by clustering the transport requests so that the workload of each group of transport requests is equal to or less than a predetermined amount, the workload of the group of transport requests being a total value of the shortest distance between a start node and an end node of each transport request included in the group of transport requests; The transportation request allocation means Among the groups of transport requests grouped by the transport request grouping means, the groups of transport requests are allocated in order starting from the transport device having the earliest end time of the previous transport plan, and Allocating to each of the transport vehicles a set of transport requests in which the end point of the transport plan of each of the transport vehicles and the start node are located at the shortest distance; The conveyor path planning means determining, as a travel route for the transport vehicle, a route obtained by connecting the shortest routes from the start node to the end node of each transport request included in the group of transport requests grouped by the transport request grouping means in a predetermined order of processing the transport requests; Based on the determined travel route of each of the transport vehicles, when the transport vehicle is at the node, a travel timing of each of the transport vehicles is determined so as to prevent collision between the transport vehicles by not causing an event in which another transport vehicle moves to the node until the transport vehicle at the node moves. Transportation planning system.

2. The transportation planning system according to claim 1, the conveyance vehicle path planning means combines the Petri nets for the determined travel paths of all the conveyance vehicles to create a Petri net for the entire conveyance vehicles, and applies a predetermined token rule to the created Petri net for the entire conveyance vehicles, thereby planning the travel timing of each conveyance vehicle so as to prevent collision between the conveyance vehicles. Transportation planning system.

3. A transport request grouping means, based on transport path information which includes multiple nodes and edges and is information on the paths along which multiple transport vehicles travel, characterizes multiple transport requests, each of which includes information on pairs of start nodes where each transport vehicle receives luggage and end nodes representing locations to which each transport vehicle delivers the luggage it has received, using (a) an amount by which transport requests located at distant locations have different values, and (b) an amount by which transport requests whose transport paths overlap have similar values, and classifies the transport requests based on the amount characterizing the transport requests; A step in which a transport request allocation means allocates the group of transport requests to each transport machine; A step in which a conveying machine route planning means plans travel of each conveying machine based on a set of conveying requests assigned to each conveying machine so that collisions between the conveying machines do not occur; Including, the transport request grouping means, in response to the amount by which transport requests located at distant positions have different values, (a1) introduces coordinates of a midpoint of a line connecting a start node and an end node of the transport requests; In response to the amount of overlapping transport requests of the transport machine in the (b) transport path being close to each other, (b1) weighting the nodes on the transport path from the start node to the end node in the transport request based on the number of transport paths passing through the node, and introducing a value obtained by summing the weights along the transport path; Based on the amount of characteristic of the transport requests, the transport requests are clustered so that the workload of each group of transport requests is equal to or less than a predetermined amount, thereby classifying the transport requests; the workload of the set of transport requests is a sum of the shortest distances between a start node and an end node of each of the transport requests included in the set of transport requests; The transportation request allocation means allocates the group of transportation requests from the grouped groups of transportation requests in the order of the transportation device having the earliest end time of the previous transportation plan, and Allocating to each of the transport vehicles a set of transport requests in which the end point of the transport plan of each of the transport vehicles and the start node are located at the shortest distance; the conveyance vehicle route planning means determines, as a travel route for the conveyance vehicle, a route that connects the shortest routes from the start node to the end node of each of the conveyance requests included in the group of the grouped conveyance requests in a predetermined order of processing the conveyance requests; Based on the determined travel route of each of the transport vehicles, when the transport vehicle is at the node, a travel timing of each of the transport vehicles is determined so as to prevent collision between the transport vehicles by not causing an event in which another transport vehicle moves to the node until the transport vehicle at the node moves. Distribution planning method.

4. A process of characterizing a plurality of transport requests, each of which includes information on a pair of a start node where each transport device receives luggage and an end node that represents a location where each transport device delivers the luggage it has received, based on transport path information, which includes a plurality of nodes and edges and is information on the paths along which a plurality of transport devices travel, using (a) an amount by which transport requests located at distant locations have different values, and (b) an amount by which transport requests whose transport paths overlap have similar values, and then classifying the transport requests based on the amount by which the transport requests are characterized; A process of allocating the grouped sets of transport requests to each transport device; A process of planning the travel of each of the transport vehicles based on the set of transport requests assigned to each of the transport vehicles so that collisions between the transport vehicles do not occur; Run the following on your computer: In response to the amount by which transport requests located at different positions have different values, (a1) introduces coordinates of the midpoint of a line connecting the start node and the end node of the transport request, In response to the amount of overlapping transport requests of the transport machine in the (b) transport path being close to each other, (b1) weighting the nodes on the transport path from the start node to the end node in the transport request based on the number of transport paths passing through the node, and introducing a value obtained by summing the weights along the transport path; based on the amount characterizing the transport requests, the transport requests are grouped by clustering the transport requests so that the workload of each group of transport requests is equal to or less than a predetermined amount, the workload of the group of transport requests being a total value of the shortest distance between a start node and an end node of each transport request included in the group of transport requests; Among the groups of transport requests thus grouped, the groups of transport requests are allocated in order from the transport device having the earliest end time of the previous transport plan, and Allocating to each of the transport vehicles a set of transport requests in which the end point of the transport plan of each of the transport vehicles and the start node are located at the shortest distance; determining a travel route for the transport vehicle by connecting the shortest routes from the start node to the end node of each transport request included in the group of transport requests in a predetermined order of processing the transport requests; Based on the determined travel route of each of the transport vehicles, when the transport vehicle is at the node, a travel timing of each of the transport vehicles is determined so as to prevent collision between the transport vehicles by not causing an event in which another transport vehicle moves to the node until the transport vehicle at the node moves. program.

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