Goods transport facility

Abstract

To appropriately perform route selection, taking into account a route shape formed by a plurality of links.SOLUTION: A goods transport facility 100 comprises a control system 2. The control system 2 executes: a route extraction process that extracts multiple candidate routes R by referring to map information M; a cost correction amount derivation process that derives a cost correction amount Cc for each candidate route R based on a combination of shapes of each of the multiple links L that constitute the candidate route R for each of the multiple candidate routes R; and a route selection process for calculating route costs Ct of each candidate route R and selecting the candidate route R with the smallest route costs Ct from the multiple candidate routes R as a travel route for a carrier 1 based on a sum of reference costs Cs for all links L included in the candidate route R, and a cost correction amount Cc determined for each candidate route R through the cost correction amount derivation process.SELECTED DRAWING: Figure 5

Description

[Technical Field]

[0001] The present invention relates to an item transport facility that includes a predetermined route, a transport vehicle that travels along the route to transport items, and a control system that specifies a destination and a route to the destination for the transport vehicle. [Background technology]

[0002] For example, International Publication No. 2023 / 132101 (Patent Document 1) discloses a technique for selecting, from among a plurality of routes from a departure point to a destination, a route with the lowest cost as the travel route for a transport vehicle.

[0003] In the technology disclosed in Patent Document 1, the cost of curved routes is set higher than the cost of straight routes, and a travel route for a transport vehicle is selected so that the total cost of the route from the departure point to the destination is minimized. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] International Publication No. 2023 / 132101 Summary of the Invention [Problem to be solved by the invention]

[0005] As described above, in technologies for selecting a travel route with the minimum total route cost, such as that disclosed in Patent Document 1, the cost of the travel route is usually calculated by adding up predetermined link costs for each link, excluding dynamically changing costs such as congestion. The link cost of each link is set to a different value depending on whether the link is straight or curved. However, even if the total link costs set for multiple links are the same, the shape of the route formed by the multiple links will differ depending on the order of the multiple links (e.g., the order of multiple straight links and multiple curved links). The ease of travel for a transport vehicle varies depending on the shape of the route formed by such multiple links. From the perspective of selecting an appropriate route that takes into account the shape of the route formed by the multiple links, there is room for improvement in previous technologies.

[0006] In view of the above situation, it is desirable to realize a technology that can appropriately select a route while taking into consideration the shape of the route formed by multiple links. [Means for solving the problem]

[0007] a predetermined route; a transport vehicle that travels along the route to transport an item; a control system that specifies a destination and a route to the destination for the transport vehicle; An article conveying facility comprising: the path includes a plurality of nodes and a plurality of links connecting adjacent nodes; a reference cost corresponding to a required time for the transport vehicle to pass through the link is set in advance for each of the plurality of links; The control system includes: a route extraction process for extracting a plurality of candidate routes that are candidates for the route along which the transport vehicle travels from the origin to the destination, by referring to map information that is information about the route; a cost correction amount derivation process for deriving a cost correction amount for each of the plurality of candidate routes based on a combination of the shapes of the plurality of links constituting the candidate route; a route selection process that calculates a route cost of each of the candidate routes based on a sum of the reference costs for all of the links included in the candidate routes and the cost correction amount calculated for each of the candidate routes by the cost correction amount derivation process, and selects, from among the plurality of candidate routes, the candidate route with the smallest route cost as the movement route of the transport vehicle; Execute.

[0008] According to this configuration, a cost correction amount for each candidate route is derived based on the combination of the shapes of the multiple links that make up the candidate route, and the route cost is calculated using this cost correction amount. The route cost calculated in this manner can take into account not only the base cost set for each of the multiple links, but also the route shape formed by the multiple links that make up the candidate route. Therefore, according to this configuration, it is possible to select an appropriate route in the route selection process, taking into account the route shape formed by the multiple links.

[0009] Further features and advantages of the techniques according to the present disclosure will become more apparent from the following description of exemplary and non-limiting embodiments, which proceeds with reference to the drawings. [Brief explanation of the drawings]

[0010] [Figure 1] Plan view showing a part of the article transport facility [Figure 2] 10 is a flowchart showing the processing procedure for cost correction amount derivation processing. [Figure 3] A diagram showing the route cost of the first route [Figure 4] A diagram showing the route cost of the second route [Figure 5] A diagram showing the route cost of the third route DETAILED DESCRIPTION OF THE INVENTION

[0011] Hereinafter, an embodiment of an article transport facility will be described with reference to the drawings.

[0012] As shown in FIG. 1, the item conveying equipment 100 includes a predetermined route R, a transport vehicle 1 that travels along the route R to transport items (not shown), and a control system 2 that specifies a destination T and a route to the destination T for the transport vehicle 1.

[0013] In this embodiment, the route R is configured using rails. For example, the rails that configure the route R are installed near the ceiling of the facility. In this case, the transport vehicle 1 is configured as a so-called ceiling transport vehicle that travels along the route R installed near the ceiling.

[0014] Various items are handled by the item transport equipment 100. For example, the item transport equipment 100 is used in a semiconductor manufacturing factory. Therefore, the items include substrate containers (so-called FOUPs: Front Opening Unified Pods) that store substrates (wafers, panels, etc.), reticle containers (so-called reticle pods) that store reticles, magazines, trays, etc. In this case, the transport vehicle 1 transports items such as substrate containers and reticle containers along the route R between each process.

[0015] Although detailed illustration is omitted, the article transport equipment 100 has a plurality of transfer target locations to which the transport vehicle 1 transfers articles. The plurality of transfer target locations are arranged along the route R. The transfer target locations are locations where the transport vehicle 1 hands over articles or locations where the transport vehicle 1 receives articles. Examples of transfer target locations include processing ports provided in semiconductor substrate processing equipment, buffers for temporarily storing articles along the route R, and inlet ports and outlet ports located adjacent to an automated warehouse that stores articles.

[0016] The control system 2 includes a storage device that stores information input to the input device, a processing device that retrieves information from the storage device, performs arithmetic processing, and stores the arithmetic results in the storage device, and a control device that issues commands to each device. The control system 2 is configured using one or more CPUs. These CPUs are elements included in a control device fixedly installed within the facility or a control device mounted on the transport vehicle 1.

[0017] The control system 2 issues a transport command to the transport vehicle 1. The transport command includes information on the current location of the transport vehicle 1 to which the command is issued, and information on the origin and destination of the item. Upon receiving the transport command, the transport vehicle 1 moves from its current location to the origin to receive the item for which the command is issued, and after receiving the item, transports the item from the origin to the destination. The origin and destination include the above-mentioned transfer target locations.

[0018] As described above, the control system 2 specifies the destination T and the route to the destination T for the transport vehicle 1. The route is the route R from the origin F of the transport vehicle 1 to the destination T. The transport command described above also includes information about the route. The origin F is the current position of the transport vehicle 1 that is the target of the command, or the target transfer location where the item to be transported is located. The destination T is the target transfer location where the item to be transported is located, or the target transfer location to which the item to be transported is to be transported.

[0019] For example, in order to have a transport vehicle 1 that is not holding an item receive an item, the control system 2 designates the transfer target location where the item to be transported is located as the destination T, and specifies to the transport vehicle 1 a movement route from the current position (origin F) of the transport vehicle 1 to the destination T. Alternatively, the control system 2 designates the transfer target location where the item to be transported is located as the origin F, and the transfer target location to which the item to be transported is to be transported as the destination T, and specifies to the transport vehicle 1 a movement route from the origin F to the destination T.

[0020] As shown in FIG. 1, a route R includes a plurality of nodes N and a plurality of links L connecting adjacent nodes N. In FIG. 1, the plurality of nodes N are indicated by "A to H," and the plurality of links L are indicated by "L1 to L7." In the following description, when referring to a specific node N, it will be expressed as node A, node B, etc., and when there is no particular distinction between them, it will be expressed as "node N." Furthermore, when referring to a specific link L, it will be expressed as link L1, link L2, etc., and when there is no particular distinction between them, it will be expressed as "link L."

[0021] In this embodiment, the links L include straight links La and curved links Lb. The straight links La are links L formed in a straight line. The curved links Lb are links L formed in a curved line. The curved links Lb are links L with at least a smaller radius of curvature than the straight links La. In this example, if at least a portion of a single link L is formed in a curved line, the link L is classified as a curved link Lb. For example, the N-shaped link L connecting nodes A and E in the figure is classified as a curved link Lb because the branching points and merging points with other links L are formed in curved lines.

[0022] The node N is a branch point or a junction of the route R, or a boundary point between the straight link La and the curved link Lb.

[0023] A reference cost Cs corresponding to the time required for the transport vehicle 1 to pass through the link L is set in advance for each of the multiple links L. The reference cost Cs is a fixed value set for each link L, and is set based on the surrounding environment of the link L, such as the length and structure of the link L, or the presence or absence of a station (a transfer target location). In this example, the unit of the reference cost Cs is "seconds (s)". In this embodiment, a straight-line distance, which is the length of the straight-line link La, is set for the straight-line link La. The reference cost Cs of the straight-line link La is set based on at least the straight-line distance. This allows the reference cost Cs of the straight-line link La to be set appropriately.

[0024] The control system 2 is configured to be able to refer to map information M, which is information about the route R. The map information M includes the shape of each link L that constitutes the route R, the connection relationship of each link L, the reference cost Cs of each link L, the length of each link L (for example, in meters [m]), etc. For example, the map information M is stored in a database (not shown). The control system 2 acquires the map information M from the database and executes various processes based on the map information M. When the map information M is updated by processing by the control system 2, the updated map information M is stored again in the database.

[0025] In the layout shown in FIG. 1, there are multiple routes R from the origin F to the destination T. The control system 2 selects the most rational route R from these routes R as the route along which the transport vehicle 1 should travel. The route R is selected based on the route cost Ct (see FIG. 3, etc.) calculated for each route R.

[0026] The control system 2 refers to map information M, which is information on the route R, and executes a route extraction process to extract a plurality of candidate routes R, which are candidates for the route R along which the transportation vehicle 1 travels from the origin F to the destination T.

[0027] In addition, the control system 2 executes a cost correction amount derivation process for each of the multiple candidate routes R, which derives a cost correction amount Cc (see Figure 3, etc.) for each candidate route R based on the combination of the shapes of the multiple links L that constitute the candidate route R.

[0028] Furthermore, the control system 2 calculates the route cost Ct of each candidate route R based on the sum of the reference costs Cs for all links L included in the candidate route R and the cost correction amount Cc obtained for each candidate route R by the cost correction amount derivation process, and performs a route selection process to select the candidate route R with the smallest route cost Ct from among the multiple candidate routes R as the travel route for the transport vehicle 1.

[0029] That is, the control system 2 does not simply calculate the route cost Ct from the reference cost Cs of each link L, but calculates the route cost Ct for each candidate route R using the cost correction amount Cc obtained by the cost correction amount derivation process. This makes it possible to select an appropriate route.

[0030] In this embodiment, a reference cost Cs is not set for the curved link Lb. In this embodiment, only the cost of the straight link La is considered. That is, the control system 2 calculates the route cost Ct based only on the cost of the straight link La in the route selection process. The traveling speed of the guided vehicle 1 tends to be relatively constant on the curved link Lb under any circumstances. Therefore, regardless of which route R is selected, as long as the guided vehicle 1 passes through the same curved link Lb, the time required for the guided vehicle 1 to travel on that curved link Lb will be relatively constant. Therefore, the cost on the curved link Lb can be ignored. From this perspective, in this embodiment, unnecessary cost calculations can be eliminated, thereby enabling rational route selection. However, the description in this specification does not exclude a configuration in which the route cost Ct is calculated taking the cost of the curved link Lb into consideration.

[0031] FIG. 2 shows the procedure for deriving the cost correction amount.

[0032] In this embodiment, a section of the candidate route R in which one or more straight links La are consecutively sandwiched between two curved links Lb is defined as a target straight section SA, and its length is defined as a continuous straight distance DA.

[0033] In the cost correction derivation process, first, it is determined whether or not a target straight section SA exists on candidate route R (step #1). If it is determined that a target straight section SA exists on candidate route R (step #1: Yes), it is determined whether or not the length of the target straight section SA, i.e., the continuous straight distance DA, is less than threshold value X (step #2).

[0034] If it is determined that the continuous straight-line distance DA is less than the threshold value X (step #2: Yes), a cost correction amount Cc is derived so as to increase the route cost Ct of the candidate route R (step #3). That is, in the cost correction amount derivation process, when the candidate route R includes a target straight-line section SA with a continuous straight-line distance DA less than the predetermined threshold value X, the cost correction amount Cc is derived so as to increase the route cost Ct of the candidate route R compared to when the candidate route R does not include a target straight-line section SA with a continuous straight-line distance DA less than the threshold value X. As a result, the candidate route R has a relatively large route cost Ct, making it less likely to be selected as the movement route of the transport vehicle 1 from the source F to the destination T.

[0035] In this embodiment, if it is determined in step #1 that the candidate route R does not have a target straight section SA (step #1: No), the cost correction amount Cc is set to zero. Also, if it is determined in step #2 that the continuous straight-driving distance DA is equal to or greater than the threshold value X (step #2: No), the cost correction amount Cc is set to zero.

[0036] The calculation of the route cost Ct of the candidate route R will be specifically described with reference to Figs. 3 to 5. In the layout shown in Fig. 1, there are three candidate routes R heading from the source F to the destination T. Of these candidate routes R, Fig. 3 shows the first route, Fig. 4 shows the second route, and Fig. 5 shows the third route. In this example, the control system 2 can extract the first route, the second route, and the third route in the route extraction process.

[0037] 3, the first route is a route R from the source F to the destination T, on which nodes A, B, C, D, and H are arranged in this order. In this case, the first route is configured to include link L1, link L2, link L3, link L4, and link L5.

[0038] First, it is determined whether the first route includes a target straight section SA. In the first route shown in FIG. 3, only a curved link Lb exists between node C and node D, and no other curved links Lb exist. The condition for the target straight section SA to exist in the candidate route R (hereinafter referred to as the "target straight section existence condition") is that at least two or more curved links Lb exist in the candidate route R, and that a straight link La exists between these curved links Lb. In the first route shown in FIG. 3, there is only one curved link Lb, so the above condition is not satisfied. Therefore, the first route does not include the target straight section SA, and as described above, in this embodiment, the cost correction amount Cc in this case is set to zero.

[0039] The route cost Ct of the first route is calculated simply by adding up the reference costs Cs of each link L that constitutes the first route. In this example, the route cost Ct of the first route is calculated as "18s" by adding up the reference cost Cs of link L1, "4s," the reference cost Cs of link L2, "6s," the reference cost Cs of link L3, "1s," the reference cost Cs of link L4, and the reference cost Cs of link L5, "2s" (4s + 6s + 5s + 1s + 2s = 18s).

[0040] 4, the second route is a route R from the source node F to the destination node T, in which node A, node E, node F, node G, and node H are arranged in this order. In this case, the second route is configured to include link L1, link L6, link L7, and link L5.

[0041] First, it is determined whether the second route includes a target straight section SA. The second route shown in FIG. 4 has a curved link Lb between node A and node E, and a curved link Lb between node G and node H. Furthermore, links L6 and L7, which are straight links La, are located between these two curved links Lb. Therefore, the second route shown in FIG. 4 satisfies the target straight section existence condition. Therefore, it is determined that the second route includes a target straight section SA.

[0042] Since the second route includes the target straight section SA, it is next determined whether the continuous straight distance DA, which is the length of the target straight section SA, is less than the threshold value X. The threshold value X is a fixed value determined in advance through experiments or the like, but it may also be a variable value that can change depending on the operation of the facility and the situation at the time. In this example, the threshold value X is a fixed value, set to, for example, 6 meters (m).

[0043] 4, the continuous straight-ahead distance DA of the target straight section SA including links L6 and L7 is calculated as 8 m by adding together the length of link L6 (5 m) and the length of link L7 (3 m) (5 m + 3 m = 8 m). Therefore, the continuous straight-ahead distance DA of the second route (8 m) is equal to or greater than the threshold value X (6 m), and as described above, in this embodiment, the cost correction amount Cc in this case is set to zero.

[0044] The route cost Ct of the second route is calculated simply by adding up the reference costs Cs of each link L that makes up the second route. In this example, the route cost Ct of the second route is calculated as 16s by adding up the reference cost Cs of link L1, which is 4s, the reference cost Cs of link L6, which is 6s, the reference cost Cs of link L7, which is 4s, and the reference cost Cs of link L5, which is 2s (4s + 6s + 4s + 2s = 16s).

[0045] 5, the third route is a route R from the source F to the destination T, in which node A, node B, node F, node G, and node H are arranged in this order. In this case, the third route is configured to include link L1, link L2, link L7, and link L5.

[0046] First, it is determined whether the third route includes a target straight section SA. The third route shown in Figure 5 has a curved link Lb between node B and node F, and a curved link Lb between node G and node H. Then, link L7, which is a straight link La, is sandwiched between these two curved links Lb. Therefore, the third route shown in Figure 5 satisfies the target straight section existence condition. Therefore, it is determined that the third route includes a target straight section SA.

[0047] Since the third route includes the target straight section SA, it is next determined whether the continuous straight distance DA, which is the length of the target straight section SA, is less than the threshold value X. As described above, in this example, the threshold value X is set to "6 meters (m)."

[0048] In the third route shown in Figure 5, the continuous straight-line distance DA of the target straight section SA including link L7 is equal to the length of link L7, which is 3 m. Therefore, the continuous straight-line distance DA is calculated as 3 m (3 m = 3 m). Therefore, the continuous straight-line distance DA of the third route (3 m) is less than the threshold value X (6 m).

[0049] The cost correction amount Cc when the continuous straight-driving distance DA is less than the threshold value X is set to a value greater than the cost correction amount Cc (zero in this example) when the continuous straight-driving distance DA is equal to or greater than the threshold value X. Therefore, in this embodiment, the cost correction amount Cc when the continuous straight-driving distance DA is less than the threshold value X is set to 1 second (s) or greater. Here, the cost correction amount Cc in this case is set to a fixed value, which is set to "3s" in this example.

[0050] The route cost Ct of the third route is calculated based on the reference cost Cs and the cost correction amount Cc of each link L constituting the third route. In this embodiment, the route cost Ct is calculated by adding the cost correction amount Cc to the sum of the reference costs Cs of each link L. In this example, the route cost Ct of the third route is calculated as "19s" by adding the cost correction amount Cc of "3s" to the sum of the reference cost Cs of link L1 of "4s," the reference cost Cs of link L2 of "6s," the reference cost Cs of link L7 of "4s," and the reference cost Cs of link L5 of "2s" (4s + 6s + 4s + 2s + 3s = 19s).

[0051] From the above, when the first to third routes exemplified in FIGS. 3 to 5 are set as candidate routes R, the second route (route cost Ct=16s) with the smallest route cost Ct is selected as the movement route of the transport vehicle 1 from the source F to the destination T. The route selection process is performed by sequentially extracting possible route R patterns from the source F to the destination T. However, without being limited to this, the route selection process may be performed by extracting all candidate routes R from the source F to the destination T, and then calculating the route cost Ct for each of these candidate routes R.

[0052] In the above example, the second route and the third route each include only one target straight section SA. However, the candidate route R may include multiple target straight sections SA.

[0053] Therefore, in the cost correction amount derivation process according to this embodiment, a cost correction amount Cc is derived for each target straight section SA. Then, the sum of the reference costs Cs for all links L included in each target straight section SA is defined as the target straight section reference cost Csa. In the route selection process, the route cost Ct of each candidate route R is calculated based on the target straight section reference cost Csa of each target straight section SA included in the candidate route R corrected using the cost correction amount Cc derived for each target straight section SA. For example, the third route shown in FIG. 5 includes one target straight section SA, and the target straight section reference cost Csa of the target straight section SA is set to "7s," which is the sum of the reference cost Cs of link L7, "4s," and the cost correction amount Cc, "3s."

[0054] That is, in this embodiment, when one candidate route R includes multiple target straight sections SA, a cost correction amount Cc is derived for each target straight section SA, and all of the derived cost correction amounts Cc are reflected in the route cost Ct of the candidate route R. In this example, the route cost Ct is calculated by adding up all of the cost correction amounts Cc.

[0055] Other Embodiments Next, other embodiments will be described.

[0056] (1) In the above embodiment, an example has been described in which the route cost Ct is calculated by adding the cost correction amount Cc to the sum of the reference costs Cs of each link L. However, without being limited to this example, the route cost Ct may be calculated by multiplying the sum of the reference costs Cs of each link L by the cost correction amount Cc. Note that, depending on the method for deriving the cost correction amount Cc, the derived cost correction amount Cc may be subtracted or divided.

[0057] (2) In the above embodiment, the cost correction amount derivation process derives a cost correction amount Cc such that the route cost Ct of a candidate route R is larger when the candidate route R includes a target straight-line section SA with a continuous straight-line distance DA less than a predetermined threshold X than when the candidate route R does not include a target straight-line section SA with a continuous straight-line distance DA less than the threshold X. However, the present invention is not limited to this example, and the cost correction amount Cc may be derived using logic opposite to that described above. That is, in the cost correction amount derivation process, when the candidate route R does not include a target straight-line section SA with a continuous straight-line distance DA less than the predetermined threshold X, the cost correction amount Cc may be derived such that the route cost Ct of the candidate route R is smaller than when the candidate route R includes a target straight-line section SA with a continuous straight-line distance DA less than the threshold X. This also makes it less likely that a candidate route R with a high cost will be selected.

[0058] (3) In the above embodiment, an example has been described in which the cost correction amount Cc is a fixed value (3 seconds [s] in the above) when the continuous straight-line distance DA is less than the threshold value X. However, without being limited to such an example, the cost correction amount Cc may be a value obtained by adding a variable value set according to the number of guided vehicles 1 existing on the link L (congestion level) at the time when the cost correction amount derivation process is performed or at a future time (fixed value + variable value). Alternatively, the cost correction amount Cc may be set based on a learning value based on the past operating performance of the guided vehicles 1.

[0059] (4) In the above embodiment, an example has been described in which the value of the cost correction amount Cc changes depending on whether the continuous straight-driving distance DA is less than the threshold value X. However, without being limited to such an example, the cost correction amount Cc may be a variable value that changes gradually or in stages depending on the length of the continuous straight-driving distance DA, without depending on the threshold value X.

[0060] (5) In the above embodiment, an example has been described in which the transport vehicle 1 is configured as a so-called ceiling transport vehicle that travels along a route R installed near the ceiling. However, the transport vehicle 1 is not limited to this example, and may be a tracked vehicle or a trackless vehicle. If the transport vehicle 1 is a trackless vehicle (a so-called AGV), the route R may be configured using a magnetic tape installed on the floor or a two-dimensional code containing position information.

[0061] (6) The configurations disclosed in the above-described embodiments may be combined with configurations disclosed in other embodiments as long as no contradictions arise. Regarding other configurations, the embodiments disclosed in this specification are merely examples in all respects. Therefore, various modifications may be made as appropriate within the scope of the present disclosure.

[0062] [Summary of this embodiment] The summary of this embodiment will be described below.

[0063] a predetermined route; a transport vehicle that travels along the route to transport an item; a control system that specifies a destination and a route to the destination for the transport vehicle; An article conveying facility comprising: the path includes a plurality of nodes and a plurality of links connecting adjacent nodes; a reference cost corresponding to a required time for the transport vehicle to pass through the link is set in advance for each of the plurality of links; The control system includes: a route extraction process for extracting a plurality of candidate routes that are candidates for the route along which the transport vehicle travels from the origin to the destination, by referring to map information that is information about the route; a cost correction amount derivation process for deriving a cost correction amount for each of the plurality of candidate routes based on a combination of the shapes of the plurality of links constituting the candidate route; a route selection process that calculates a route cost of each of the candidate routes based on a sum of the reference costs for all of the links included in the candidate routes and the cost correction amount calculated for each of the candidate routes by the cost correction amount derivation process, and selects, from among the plurality of candidate routes, the candidate route with the smallest route cost as the movement route of the transport vehicle; Execute.

[0064] According to this configuration, a cost correction amount for each candidate route is derived based on the combination of the shapes of the multiple links that make up the candidate route, and the route cost is calculated using this cost correction amount. The route cost calculated in this manner can take into account not only the base cost set for each of the multiple links, but also the route shape formed by the multiple links that make up the candidate route. Therefore, according to this configuration, it is possible to select an appropriate route in the route selection process, taking into account the route shape formed by the multiple links.

[0065] The links include straight links and curved links, The length of a target straight section in the candidate route, which is a section in which one or more straight links sandwiched between two of the curved links are continuous, is defined as a continuous straight distance, In the cost correction amount derivation process, it is preferable that when the candidate route includes the target straight section with the continuous straight-line distance less than a predetermined threshold, the cost correction amount is derived so that the route cost of the candidate route is larger than when the candidate route does not include the target straight-line section with the continuous straight-line distance less than the threshold.

[0066] As the distance that a transport vehicle can travel continuously in a straight line increases, the average travel speed of the transport vehicle tends to increase, and as that distance decreases, the average travel speed of the transport vehicle tends to decrease. According to this configuration, when a candidate route includes a section where the continuous straight-line distance is relatively short, a cost correction amount is derived so that the route cost is higher than that of a candidate route that does not include such a section. Therefore, according to this configuration, in the route selection process, a candidate route that is likely to result in a low average travel speed of the transport vehicle is less likely to be selected, and a candidate route that is likely to result in a high average travel speed of the transport vehicle is more likely to be selected. This makes it possible to select an appropriate route that takes into account the route shape formed by multiple links.

[0067] A straight-line distance, which is the length of the straight-line link, is set for the straight-line link, Preferably, the reference cost of the straight-line link is set based on at least the straight-line distance.

[0068] The longer the straight-line link, the longer the time required for the transport vehicle to pass through that straight-line link, and therefore the larger the reference cost. With this configuration, the reference cost of the straight-line link is set to be larger as the straight-line distance of the straight-line link increases. Therefore, the reference cost of the straight-line link can be set appropriately.

[0069] In the cost correction amount derivation process, the cost correction amount is derived for each of the target straight line sections; The sum of the reference costs for all the links included in each of the target straight sections is defined as the target straight section reference cost, In the route selection process, it is preferable to calculate the route cost of each of the candidate routes based on a value obtained by correcting the target straight section reference cost of each of the target straight sections included in the candidate route using the cost correction amount derived for each of the target straight section.

[0070] According to this configuration, when a candidate route includes multiple target straight sections, a cost correction amount is derived for each target straight section, so that the route cost can be calculated appropriately even for such a candidate route. [Industrial Applicability]

[0071] The technology disclosed herein can be used in an item transport facility that includes a predetermined route, a transport vehicle that travels along the route to transport items, and a control system that specifies a destination and a route to the destination for the transport vehicle. [Explanation of symbols]

[0072] 100: Goods transport equipment 1: Transport vehicle 2: Control system Cc: Cost adjustment amount Cs: Baseline cost Csa: Standard cost of target straight section Ct: Route cost DA: Continuous straight distance F: Source T: Destination R: Route L: Link La: Linear link Lb: Curved link N: Node SA: Target straight section M: Map information X: Threshold

Claims

1. a predetermined route; a transport vehicle that travels along the route to transport an item; a control system that specifies a destination and a route to the destination for the transport vehicle; An article conveying facility comprising: the path includes a plurality of nodes and a plurality of links connecting adjacent nodes; a reference cost corresponding to a required time for the transport vehicle to pass through the link is set in advance for each of the plurality of links; The control system includes: a route extraction process for extracting a plurality of candidate routes that are candidates for the route along which the transport vehicle travels from the origin to the destination, by referring to map information that is information about the route; a cost correction amount derivation process for deriving a cost correction amount for each of the plurality of candidate routes based on a combination of the shapes of the plurality of links constituting the candidate route; a route selection process that calculates a route cost of each of the candidate routes based on a sum of the reference costs for all of the links included in the candidate routes and the cost correction amount calculated for each of the candidate routes by the cost correction amount derivation process, and selects, from among the plurality of candidate routes, the candidate route with the smallest route cost as the movement route of the transport vehicle; Implementing this, goods transport equipment.

2. The links include straight links and curved links, The length of a target straight section, which is a section in which one or more straight links sandwiched between two of the curved links are continuous, in the candidate route is defined as a continuous straight distance, 2. The item transport equipment according to claim 1, wherein in the cost correction amount derivation process, when the candidate route includes the target straight section with the continuous straight-line distance less than a predetermined threshold, the cost correction amount is derived so that the route cost of the candidate route is larger than when the candidate route does not include the target straight-line section with the continuous straight-line distance less than the threshold.

3. A straight-line distance, which is the length of the straight-line link, is set for the straight-line link, The article transport facility according to claim 2 , wherein the reference cost of the straight-line link is set based on at least the straight-line distance.

4. In the cost correction amount derivation process, the cost correction amount is derived for each of the target straight line sections; The sum of the reference costs for all the links included in each of the target straight sections is defined as the target straight section reference cost, 4. The item transport facility according to claim 2, wherein in the route selection process, the route cost of each of the candidate routes is calculated based on a value obtained by correcting the target straight section standard cost of each of the target straight sections included in the candidate route using the cost correction amount derived for each of the target straight section.

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