Transport vehicle system

Abstract

To make an allocation of conveyance so that an upstream-side conveyance vehicle does not have to wait due to a loading of a downstream-side conveyance vehicle, in a conveyance vehicle system in which multiple conveyance vehicles and multiple stations are arranged on a lap route.SOLUTION: A conveyance vehicle system (100) comprises: a lap route (L); a loadable conveyance vehicle (v) running one way along the lap route (L); multiple stations (ST) arranged along the lap route (L), which can load goods to or unload goods from multiple conveyance vehicles (v); and a vehicle dispatch controller (10) that can make allocation of multiple stations (ST) receiving multiple conveyance requests to multiple loadable conveyance vehicles (v).SELECTED DRAWING: Figure 1A

Description

[Technical field]

[0001] The present disclosure relates to a guided vehicle system that assigns guided vehicles on a circular route to stations having transportation requests. [Background technology]

[0002] In warehouses, factories, and the like, automated guided vehicle systems are used to transport goods on a circular route. There are automated guided vehicles that use tracked vehicles, linear motor-type tracked vehicles, and automated guided vehicles (AGVs). The automated guided vehicle system includes a circular route, a vehicle that travels in one direction on the circular route to transport goods, and a station that is arranged on the circular route and unloads the goods. Loading and unloading are performed between the station and the vehicle. Here, loading refers to loading goods from the station onto the vehicle, and unloading refers to unloading goods from the vehicle to the station. In an automated guided vehicle system having multiple stations and multiple vehicles, it is an issue to determine which vehicle to assign to which station. Patent Document 1 discloses one assignment method in a vehicle system. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2010-064806 A Summary of the Invention [Problem to be solved by the invention]

[0004] In a transport vehicle system, a method of allocating transport vehicles to stations is generally used in which "the transport vehicles are allocated to the transport vehicles closest to the stations in the order in which transport requests are generated at the stations." Here, as a simple case, let us assume two stations that are ready to load goods at the same time, and two transport vehicles capable of loading goods that are consecutive to the upstream side of the two stations. If the downstream transport vehicle closest to the upstream station is allocated first, the upstream transport vehicle will be allocated to the remaining downstream stations. When loading is performed in this way, the downstream transport vehicle will arrive at the upstream station first and load the goods. The upstream transport vehicle cannot proceed further and has to stop until the downstream transport vehicle finishes loading. In other words, the upstream transport vehicle cannot reach the downstream station easily. With the conventional method, efficient loading is not possible overall.

[0005] The present disclosure aims to provide a transport vehicle system that allows for efficient transport of goods by allocating a plurality of transport vehicles to a plurality of stations. [Means for solving the problem]

[0006] In order to solve the above problems, the transport vehicle system of the present disclosure includes: A circular route, A plurality of transport vehicles capable of carrying articles and traveling in one direction along the circular route; a plurality of stations disposed along the circular path and capable of loading or unloading the plurality of transport vehicles; a vehicle dispatch controller that assigns a plurality of stations having transportation requests to a plurality of vehicles capable of loading cargo; Equipped with The dispatch controller, A starting point is obtained based on the positions of a plurality of stations having transportation requests and the positions of a plurality of transport vehicles capable of loading cargo; The starting point is (1) The station where the transport request is made, (2) A vehicle capable of carrying cargo; or (3) A circuit path between the station with the transportation request and the nearest downstream transport vehicle that can load the load; When the station with the transportation request set as the starting point is set as the first station and the carrier that can be loaded set as the starting point is set as the first carrier, Allocating a transport vehicle capable of loading a load to a station having a transport request in order from the first station to the upstream side, starting from a second transport vehicle capable of loading a load that is closest to the upstream side of the starting point, or For a transport vehicle capable of loading a cargo, stations having a transport request on the downstream side are allocated in order from the first transport vehicle to the second station having a transport request that is closest downstream from the starting point.

[0007] In this disclosure, the downstream side refers to the direction in which the transport vehicle travels on the circuit route, and the upstream side refers to the direction in which the transport vehicle has traveled on the circuit route. In other words, the front side of the transport vehicle in the traveling direction is the downstream side, and the rear side of the transport vehicle in the traveling direction is the upstream side.

[0008] The transportation means loading of goods from a station onto a transport vehicle, the transport vehicle loaded with the goods traveling along a circuitous route to another station, and the process of unloading the goods from the transport vehicle to the other station.

[0009] A transportation request is a request from a station or the like to a vehicle dispatch controller to transport an item prepared at the station. An item being prepared at a station means that the item is placed at a loading position for a transport vehicle at the station.

[0010] A station with a transportation request means a station where an item is prepared or being prepared in a position where it can be loaded onto a transport vehicle, and does not include a station where an item is not prepared or a station for unloading an item from a transport vehicle.

[0011] A loadable transport vehicle is a transport vehicle that is not loaded with an item. Alternatively, a loadable transport vehicle is a transport vehicle that is not loaded with an item, or a transport vehicle that is currently loaded with an item but is scheduled to be unloaded in the future.

[0012] The transport vehicle system of the present disclosure can allocate transport so that an upstream transport vehicle is not forced to wait due to loading of cargo on a downstream transport vehicle.

[0013] A more preferable method for setting the starting point is to The vehicle dispatch controller determines a starting point based on the positions of all stations with transportation requests within a circular route and the positions of all transport vehicles available for loading.

[0014] By setting the starting point in this way, it is possible to more appropriately allocate transport.

[0015] The first transport vehicle can be set as follows: The multiple loadable transport vehicles on the circular route may be classified into consecutive transport vehicle groups on the circular route without including any station with a transport request in between, and the loadable transport vehicle most upstream among the loadable transport vehicles of one of the transport vehicle groups may be designated as the first transport vehicle.

[0016] By setting the first transporting vehicle in this manner, a starting point is set, and an allocation method suitable for at least the selected group of transporting vehicles can be provided.

[0017] Also, the method for setting up the first station is as follows: The stations for which the transport request is made may be classified into consecutive station groups on the circular route without any transport vehicles capable of loading cargo therebetween, and the station for which the transport request is made furthest downstream among the stations for which the transport request is made in one of the station groups may be designated as the first station.

[0018] By setting the first station in this manner, a starting point is set, and an allocation method suitable for at least the selected group of stations can be provided.

[0019] Another method for setting the first transport vehicle is as follows: classifying the plurality of loadable transport vehicles on the circular route into a group of continuous transport vehicles on the circular route without including any station having a transport request therebetween; classifying the stations for which the transportation request is made into a group of consecutive stations on the circular route without including a transporting vehicle capable of loading cargo therebetween; A ratio is calculated by dividing the number of vehicles capable of loading cargo in the group of vehicles by the number of stations having transportation requests in the group of stations that is closest to the group of vehicles downstream; Among the group of transporting vehicles having the largest value of the ratio, the transporting vehicle most upstream capable of loading cargo is set as the first transporting vehicle.

[0020] By setting the first transporting vehicle in this way and setting the starting point, even if there are multiple groups of transporting vehicles that can be continuously loaded on the circuit route, it is possible to set an optimal starting point for the entire circuit route. In other words, it is possible to set a better starting point than when focusing on one group arbitrarily selected from multiple transporting vehicle groups.

[0021] Another way to set up the first station is classifying the plurality of loadable transport vehicles on the circular route into a group of continuous transport vehicles on the circular route without including any station having a transport request therebetween; classifying the stations for which the transportation request is made into a group of consecutive stations on the circular route without including a transporting vehicle capable of loading cargo therebetween; A second ratio is calculated by dividing the number of stations in the group of stations with a transport request by the number of transport vehicles capable of loading cargo in the group of transport vehicles closest to the group of stations upstream, and the station with the transport request furthest downstream among the group of stations with the largest second ratio value is designated as the first station.

[0022] By setting the first station in this way and setting the starting point, even if there are multiple station groups with consecutive transport requests on the circuit route, it is possible to set an optimal starting point for the entire circuit route. In other words, it is possible to set a better starting point than when focusing on one station group arbitrarily selected from multiple station groups.

[0023] Another way to set the origin is An arbitrary point on the transport path is set as an origin, and the origin is assigned a zero point; If there is a transport vehicle that can load cargo on the upstream side of the transport route from the origin, +1 point is added, and the added point is given to the transport vehicle. If there is a station with a transport request on the upstream side, -1 point is added, and the added point is given to the station. Among all the transport vehicles capable of loading cargo, the one with the highest score is designated as the first transport vehicle, and the first transport vehicle is used as the starting point.

[0024] In this setting method, even if the origin is set to a different number or the number or sign of the added points is changed, a calculation method that ultimately selects the same origin is an equivalent method.

[0025] In this manner, by using a method of setting the starting point by setting the first transporting vehicle, it is possible to set an optimal starting point for the entire circuit route.

[0026] When the dispatch controller performs allocation again after performing allocation once, the dispatch controller may perform allocation including transportation requests that have been allocated once but have not yet been loaded.

[0027] By performing reallocation in this manner, transportation can be more reliably allocated so as to prevent an upstream transportation vehicle from having to wait.

[0028] When setting the starting point, the dispatch controller may add transportation requests predicted to occur in the near future to the starting point calculation.

[0029] A transport request predicted to occur in the near future means that an item is being prepared at a station. An item is being prepared at a station means that the item will be placed at a loading position for a transport vehicle at the station within a predetermined time. The predetermined time is, for example, from 0 seconds to 3 seconds.

[0030] By adding transport requests that are predicted to occur in the near future to the origin calculation, frequent recalculation can be avoided. Effect of the Invention

[0031] According to the transport vehicle system of the present disclosure, transport can be allocated so that an upstream transport vehicle is not forced to wait due to loading of cargo by a downstream transport vehicle. [Brief description of the drawings]

[0032] [Figure 1A] 1 is a schematic diagram showing a configuration of a guided vehicle system 100 according to a first embodiment. [Figure 1B] FIG. 2 is a diagram showing grouping of stations and vehicles in the vehicle system 100 of FIG. 1A. [Diagram 2] 10 is a flowchart showing a process (up to starting point setting by a first starting point setting method) of allocating a station having a transportation request to a carrier capable of loading a cargo according to the first embodiment. [Diagram 3] 4 is a flowchart showing a process (a first allocation method after setting a starting point) of allocating a station having a transportation request to a carrier capable of loading a cargo according to the first embodiment. [Figure 4] 13 is a flowchart showing a process (up to starting point setting by a second starting point setting method) of allocating a station having a transportation request to a carrier capable of loading a cargo in the first embodiment. [Figure 5A] FIG. 11 is a schematic diagram showing the configuration of a guided vehicle system 100a according to a second embodiment. [Figure 5B]FIG. 5B is a diagram showing a virtual position of a guided vehicle v3 carrying an article in the guided vehicle system 100a of FIG. 5A. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0033] 1. First embodiment (1) Configuration of the carrier system 100 The guided vehicle system 100 of the first embodiment includes a circuit route L, a plurality of guided vehicles v1 to v6, a plurality of stations ST1 to ST12, and a vehicle allocation controller 10, as shown in FIG. 1A.

[0034] The transport vehicle system 100 transports an article from one of the stations ST1 to ST12 to another station via one of the transport vehicles v1 to v6. Here, transport refers to loading an article from one station onto one transport vehicle, traveling the circular route L to another station, and unloading the article from the one transport vehicle to the other station.

[0035] The circular route L may be tracked or trackless.

[0036] The circular route L may include a branch and merge. A transport vehicle may flow in and out of a branch route. However, even if a branch and merge is present, the present disclosure is applicable if one transport is completed within the circular route L. In other words, the present invention is applicable if a transport vehicle loaded within the circular route travels along the circular route L with goods loaded, and in principle unloads the goods within the circular route L. Conversely, if a transport vehicle flows into the circular route L from a branch, it is sufficient to perform a recalculation.

[0037] The transport vehicles v1 to v6 travel in one direction on the circular route L with or without loaded goods. The state where no goods are loaded is also referred to as a loading-ready state. There are two or more transport vehicles v1 to v6. There is no particular upper limit to the number of transport vehicles v1 to v6, but generally, the number is 100 or less. In the transport vehicle system 100 of FIG. 1, there are six transport vehicles v1 to v6. When the transport vehicle system 100 is used in a factory, the goods are products or parts for manufacturing products. An example of the parts is a semiconductor wafer. When the transport vehicle system 100 is used in logistics, the goods are cargo. The cargo is a product, a container for storing the product, or a pallet for carrying the product. An example of the container is a case, a tray, a cardboard box, or a folding container. The transport vehicles v1 to v6 may be driven by a rotary motor or a linear motor.

[0038] Normally, the guided vehicles do not overtake the preceding guided vehicle on the circular route L. In addition, the guided vehicles v1 to v6 basically have the same performance.

[0039] Stations ST1 to ST12 are arranged along a circular route L. Articles are loaded onto transport vehicles v1 to v6 from stations ST2, ST4, ST6, ST8, ST11, and ST12, and conversely, the transport vehicles v1 to v6 carrying the articles unload the articles at stations ST1, ST3, ST5, ST7, ST9, and ST10.

[0040] Stations ST1 to ST12 may be entry stations or delivery stations for the automated warehouse. Articles are transported from the entry stations to the automated warehouse and stored in the automated warehouse. Conversely, articles delivered from the automated warehouse are transported to the delivery stations.

[0041] The stations ST1 to ST12 may be picking stations. The articles unloaded from the transport vehicles v1 to v6 to the picking stations are selected and sorted. The articles selected and sorted at the picking stations are loaded onto the transport vehicles from the loading positions of the picking stations.

[0042] As described above, the stations ST1 to ST12 may have other functions, but in relation to the transport vehicles v1 to v6 on the circular route L, they have at least one of the functions of loading articles from the stations ST1 to ST12 to the transport vehicles v1 to v6 and unloading articles from the transport vehicles v1 to v6 to the stations ST1 to ST12. The stations ST1 to ST12 may have both the functions of loading and unloading articles.

[0043] The vehicle dispatch controller 10 assigns all stations with transportation requests to multiple transport vehicles capable of loading. A station with a transportation request means a station where an article is prepared or a station where an article is being prepared. A transport vehicle capable of loading means a transport vehicle that is not loaded with an article.

[0044] The dispatch controller 10 is a computer. The computer includes a processor, a storage device, and various interfaces. The processor is, for example, a CPU. The storage device is, for example, a ROM, a RAM, a HDD, an SSD, etc. The various interfaces are, for example, an A / D converter, a D / A converter, and a communication interface.

[0045] The vehicle allocation controller 10 communicates with all the transport vehicles v1 to v6. The vehicle allocation controller 10 obtains information such as the position, speed, and loading status of each of the transport vehicles v1 to v6 from each of the transport vehicles v1 to v6. Instead of obtaining this information from each of the transport vehicles v1 to v6, it may be obtained from a sensor that monitors each of the other transport vehicles v1 to v6.

[0046] Each of the stations ST1 to ST12 is equipped with a sensor that detects the placement status of the goods, etc. The placement information of the goods acquired by the sensor is sent to the dispatch controller 10.

[0047] In general, the vehicle allocation controller 10 is connected to a higher-level controller for the entire automated warehouse. The higher-level controller is, for example, a warehouse control system (WCS). Information (transport information) on where to send an item is collected in the higher-level controller. Such item transport information is transmitted from the higher-level controller to the vehicle allocation controller 10.

[0048] The vehicle allocation controller 10 receives transport information sent from a higher-level controller, information on the placement status of items obtained from sensors in each station ST1-ST12, and information on each transport vehicle v1-v6, and then allocates all stations with transport requests to multiple transport vehicles that can load cargo. After the allocation, it instructs each transport vehicle v1-v6 to which station ST1-ST12 it should head next.

[0049] (2) A method for allocating stations with transportation requests to transport vehicles A method of allocating stations with transportation requests to a plurality of carriers capable of loading cargo in the carrier system of this embodiment will be described.

[0050] Specifically, the description will be given assuming that the guided vehicle system 100 of this embodiment includes 12 stations ST1 to ST12 and six guided vehicles v1 to v6, and that each station and each guided vehicle is in the state shown in FIG. 1A.

[0051] (2-1) How to set the first starting point In the allocation method of this embodiment, a starting point is set on a circuit route first. The method of setting the starting point will be described with reference to the flowchart of FIG.

[0052] First, as a preparation, a station for which a transport request is made, a transport vehicle capable of loading a cargo, and its location are identified (S101).

[0053] A station with a transportation request means a station where an item is prepared or a station where an item is being prepared. A station where an item is prepared means that an item has arrived at a position where the item is loaded from the station to a transport vehicle. In FIG. 1A, stations ST2 and ST11 are applicable. A station where an item is being prepared means that an item will arrive in the near future (within a specified time) at a position where the item is loaded from the station to a transport vehicle. In FIG. 1A, stations ST4, ST6, ST8, and ST12 are applicable. At station ST4, an item is currently on the station and is scheduled to arrive at the loading position in 1 second. Similarly, at station ST6, an item is currently on the station and is scheduled to arrive at the loading position in 2 seconds, and at stations ST8 and ST12, an item is currently on the station and is scheduled to arrive at the loading position in 3 seconds.

[0054] In this manner, in the present disclosure, by adding the station where the article is being prepared, in other words, the transport request that is predicted to occur in the near future, to the origin calculation, it is possible to prevent frequent recalculation. The origin calculation may be performed only based on the transport request that has occurred when the article is prepared.

[0055] In this embodiment, the loadable transport vehicles are transport vehicles that are not loaded with articles. In Fig. 1, all transport vehicles v1 to v6 are applicable. Alternatively, in this embodiment, transport vehicles that are loaded with articles are not taken into consideration.

[0056] In step S101, the position on the circuit path of the transport vehicle where loading is possible is specified. The position on the circuit path of the transport vehicle may be the position at the time when the starting point is determined (current time). However, the position of the transport vehicle where loading is possible is preferably the shortest position at which the transport vehicle can be stopped by applying the brakes at the current time. In other words, it may be the shortest position at which loading is possible.

[0057] The reason why the position of the transport vehicle capable of loading is set to such a position is as follows. Even if the transport vehicle capable of loading is located upstream of the station where the transport request is made, if the transport vehicle is close to the station, the transport vehicle may not be able to stop suddenly. Therefore, the position of the transport vehicle capable of loading is set to the shortest position at which the transport vehicle can be stopped by applying the brakes at the current time (the time when the starting point is determined). Note that in this embodiment, for the sake of simplicity of explanation, the transport vehicle is assumed to be one that can be stopped instantly. Therefore, the position of the transport vehicle capable of loading is set to the current position.

[0058] In this way, stations ST2, ST4, ST6, ST8, ST11, and ST12 for which transportation requests are made, and transport vehicles v1 to v6 available for loading, and their positions, have been identified.

[0059] Next, as shown in FIG. 1B (showing the grouping of stations and vehicles in FIG. 1A), a plurality of vehicles capable of loading on the circular route L are classified into continuous vehicle groups that do not include stations with transportation requests between them (S102). Here, a group means one or more vehicles, and even a single vehicle is called a group. Since the vehicles are capable of loading, vehicles that are already loaded are not included. In the example of FIG. 1B, all vehicles v1 to v6 are capable of loading. There are no vehicles that are loaded. In the example of FIG. 1B, stations with transportation requests are stations ST2, ST4, ST6, ST8, ST11, and ST12. Stations ST1, ST3, ST5, ST7, ST9, and ST10 without transportation requests are not considered. A continuous vehicle group includes a group consisting of one vehicle. In the example of FIG. 1B, the groups of continuous vehicles are groups GV1 and GV2. Group GV1 is composed of three vehicles v6, v1, and v2. Group GV2 is composed of three guided vehicles v3, v4, and v5.

[0060] Similarly, stations with transport requests are classified into groups of consecutive stations on the circular route that do not include a transport vehicle capable of loading cargo between them (S103). The station groups include groups consisting of a single station. In the example of FIG. 1B, the groups of consecutive stations that do not include a transport vehicle capable of loading cargo between them are groups GST1 and GST2. The station group GST1 is composed of four stations, ST2, ST4, ST6, and ST8. The station group GST2 is composed of two stations, ST11 and ST12.

[0061] In the first starting point setting method according to the present disclosure, not limited to this embodiment, the above steps S102 and S103 may be performed in such a manner that step S103 is performed first and then step S102, or may be performed simultaneously or in parallel.

[0062] Next, for each group of transport vehicles capable of loading, a ratio R1 is calculated by dividing the number of transport vehicles capable of loading in the group of transport vehicles by the number of stations with transport requests in the group of stations with transport requests closest to the group of transport vehicles downstream (S104).

[0063] In the example of Fig. 1B, the following calculation is performed: In Fig. 1B, the groups of transport vehicles that can be loaded are group GV1 and group GV2.

[0064] In the group GV1, the number of vehicles v6, v1, and v2 that can load is 3. The station group with a transport request closest to the downstream side of the group GV1 is the station group GST2. The number of stations ST11 and ST12 with a transport request in the station group GST2 is 2. Therefore, when the above ratio value R1 is calculated for the group GV1, it is 3 / 2.

[0065] Similarly, in group GV2, the number of vehicles v3, v4, and v5 that can load is 3. The station group with a transport request closest to the downstream side of group GV2 is group GST1. The number of stations ST2, ST4, ST6, and ST8 with a transport request in group GST1 is 4. Therefore, when the above ratio value R1 is calculated for group GV2, it is 3 / 4.

[0066] Next, the ratio value R1 of each transport vehicle group calculated above is compared, and the transport vehicle group showing the highest ratio value R1 is selected (S105). In the example of Fig. 1B, the ratio value R1 of the transport vehicle group GV1 is 3 / 2, and the ratio value R1 of the transport vehicle group GV2 is 3 / 4, so the transport vehicle group GV1 with the larger ratio value R is selected.

[0067] Then, the most upstream transport vehicle capable of loading among the group of transport vehicles with the largest ratio value R1 is set as the starting point (S106). Here, the transport vehicle selected as the starting point is also referred to as the first transport vehicle. In the example of FIG. 1B, the most upstream transport vehicle v2 capable of loading among the group of transport vehicles GV1 is set as the starting point (first transport vehicle).

[0068] In this disclosure, the station on the circuit path L that is closest to the first transporting vehicle on the upstream side and has a transport request is called the first station. The starting point is set to the first transporting vehicle, the first station, or the circuit path between the first transporting vehicle and the first station. In other words, setting the starting point to the first transporting vehicle, setting the starting point to the first station, and setting the starting point to the circuit path between the first transporting vehicle and the first station are equivalent.

[0069] By setting the starting point in this way, even if there are multiple groups of continuous transport vehicles capable of loading cargo on the route, it is possible to set an optimal starting point for the entire route. In other words, it is possible to set a better starting point than when focusing on one group (e.g., GV1 in FIG. 1B) arbitrarily selected from the multiple transport vehicle groups.

[0070] Furthermore, in this embodiment, stations with transport requests include stations with transport requests predicted to occur in the near future (stations where items are being prepared at stations = stations where items will be placed at the loading position for the transport vehicle at the stations within a predetermined time). By adding transport requests predicted to occur in the near future to the starting point calculation, frequent recalculation can be prevented.

[0071] In the first starting point setting method of FIG. 2, steps S104 to S106 may be modified as follows.

[0072] For each station group with a transport request, a ratio value R2 is calculated by dividing the number of stations with a transport request in the station group by the number of vehicles in the transport vehicle group that is closest to the upstream side of the station group and can load cargo. Next, the ratio values ​​R2 of each station group calculated above are compared, and the station group showing the highest ratio value R2 is selected. Among the station groups with the largest ratio value R2, the station with the most downstream transport request is set as the first station and the starting point. In FIG. 1B, the station group showing the highest ratio value R2 is group GST1, and the first station that is the starting point is station ST8.

[0073] The starting point is not limited to the first transport vehicle, but may be set to the nearest station (first station) upstream of the first transport vehicle that has a transport request. The starting point may be set on the circular route between the first transport vehicle and the first station.

[0074] (2-2) First allocation method Next, a procedure in which the vehicle allocation controller 10 allocates stations with multiple transportation requests to multiple transportation vehicles capable of loading cargo will be described.

[0075] In this embodiment, there are two allocation methods.

[0076] The first method, as shown in the flowchart of Figure 3, is a method in which, for a station where a transport request has been made, the transport is assigned to an upstream transport vehicle capable of loading cargo, starting from the first station at or near the starting point, and then starting from the closest transport vehicle capable of loading cargo upstream from the starting point (called the second transport vehicle).

[0077] The above method is described in detail as follows. First, the first station, which is at or near the starting point, is assigned to the closest transport vehicle that can load cargo upstream from the starting point. This transport vehicle is designated as the second transport vehicle. Next, stations with transport requests are assigned to transport vehicles that can load cargo, in order from the first station toward the upstream side, starting from the second transport vehicle toward the upstream side.

[0078] In the example of FIG. 1B, first, the second transport vehicle v3 is assigned to the first station ST8, which is the starting point or close to the starting point (S111). Next, the transport vehicle v4 that is upstream of the second transport vehicle is assigned to the station ST6 with a transport request upstream of the first station (S112). Similarly, the transport vehicle v5 that is upstream of the second transport vehicle is assigned to the station ST4 with a transport request (S113), then the transport vehicle v6 that is upstream of the station ST2 with a transport request, the transport vehicle v1 that is upstream of the station ST12 with a transport request, and the transport vehicle v2 that is upstream of the station ST11 with a transport request, and the assignment is completed (S120).

[0079] The allocation is performed by the vehicle dispatch controller 10, and the determined allocation is communicated to each transportation vehicle, which then carries out the transportation.

[0080] By carrying out the above-mentioned allocation, it is possible to allocate transportation so that an upstream transportation vehicle is not made to wait due to loading from a station of a downstream transportation vehicle.

[0081] (2-3) Second allocation method In this embodiment, the second method of allocation is as follows.

[0082] For transport vehicles that can load cargo, stations with transport requests downstream are assigned, starting from the first transport vehicle at or near the starting point, in order from the closest station (called the second station) with a transport request downstream from the starting point.

[0083] The above method is described in detail as follows. First, a first transport vehicle at or near the starting point is assigned to the closest station downstream from the starting point that has a transport request. This station is called the second station. Next, transport vehicles that can be loaded are assigned in order from the first transport vehicle toward the downstream side to stations that have a transport request, in order from the second station toward the downstream side.

[0084] In the example of FIG. 1B, first, the second station ST11 is assigned to the first transporting vehicle v2 that is at or near the starting point. Next, the station ST12 downstream of the second station ST11 with a transport request is assigned to the loadable transporting vehicle v1 downstream of the first transporting vehicle v2. Similarly, the station ST2 with a transport request is assigned to the loadable transporting vehicle v6, then the station ST4 with a transport request is assigned to the loadable transporting vehicle v5, the station ST6 with a transport request is assigned to the loadable transporting vehicle v4, and the station ST8 with a transport request is assigned to the loadable transporting vehicle v3, and the assignment is completed.

[0085] The allocation is performed by the vehicle dispatch controller 10, and the determined allocation is communicated to each transportation vehicle, which then carries out the transportation.

[0086] Similarly to the first allocation method, the second allocation method also makes it possible to allocate transportation so that upstream transport vehicles are not kept waiting due to loading of cargo on downstream transport vehicles.

[0087] In this embodiment, in the transport vehicle system 100 of FIG. 1, the allocation result is the same whether the allocation is performed by the first method or the second method. The reason is that the number of stations with transport requests and the number of transport vehicles that can be loaded are the same. When the number of stations with transport requests and the number of transport vehicles that can be loaded are different, the result will differ depending on whether the first method or the second method is selected. Regardless of which method is used for allocation, transport can be allocated so that upstream transport vehicles are not kept waiting due to loading by downstream transport vehicles.

[0088] As described above, once allocation is performed by the vehicle dispatch controller 10, a command is issued to the vehicle, and the vehicle starts traveling to execute the transport command, the loading status of the vehicle, the position, and the preparation status of the item at the station change. In the vehicle system 100 of this embodiment, reallocation is performed when a new transport request occurs at any station. This reallocation includes transport requests that have been allocated once but have not yet been loaded. In other words, reallocation is performed for all stations where items are prepared or are being prepared at the time of reallocation. From the viewpoint of the vehicle, this includes vehicles that have been allocated once but have not yet been loaded.

[0089] By performing reallocation in this manner, transportation can be more reliably allocated so as to prevent an upstream transportation vehicle from having to wait.

[0090] (2-4) How to set the second starting point A method for applying the second starting point setting method to the guided vehicle system 100 of FIG. 1A will be described with reference to the flowchart of FIG.

[0091] First, in the same manner as in the first starting point setting method, a station for which a transportation request has been made, a transportation vehicle capable of loading a cargo, and its location are identified (S121).

[0092] Next, in the second starting point setting method, an origin O is set at an arbitrary point on the circuit path L, and 0 points are assigned to the origin O (S122). Then, from the origin O, points are assigned to vehicles that can be loaded and stations with transport requests in order from the origin O to the upstream side (S123). If there is a vehicle that can be loaded upstream of the origin O, +1 point is added, and the resulting point is assigned to the vehicle. If there is a station with a transport request upstream, -1 point is added, and the resulting point is assigned to the station. Then, the circuit path L goes around once until it returns to the origin, and the vehicle that can be loaded and has been assigned the highest point is set as the starting point (S124).

[0093] In the example of FIG. 1A, starting from the origin O, the first loadable transport vehicle v5 is given +1 point. Next, since there is a station ST12 with a transport request on the upstream side, +1-1=0 point is given. Continuing this upstream, in order, station ST11 with a transport request gets -1 point, loadable transport vehicle v6 gets 0 point, loadable transport vehicle v1 gets +1 point, loadable transport vehicle v2 gets +2 points, station ST8 with a transport request gets +1 point, station ST6 with a transport request gets 0 point, station ST4 with a transport request gets -1 point, station ST2 with a transport request gets -2 points, loadable transport vehicle v3 gets -1 point, and loadable transport vehicle v4 gets 0 point. Therefore, in the case of FIG. 1A, the loadable transport vehicle v2 has the highest score. In this case, the loadable transport vehicle v2 is set as the starting point.

[0094] This method of setting the starting point also makes it possible to set the optimal starting point for the entire circuit route.

[0095] (2-5) Variations 1 and 2 of the method for setting the first starting point In the method of the first modification, steps S101 to S103 are the same as those in the first embodiment. In the first starting point setting method, a group of transport vehicles showing the highest ratio value R1 is selected in steps S104 and S105. In the starting point setting method of the first modification, a group of transport vehicles capable of loading is selected arbitrarily. Then, as in step S106 of the first starting point setting method, the transport vehicle capable of loading that is the most upstream of the group of transport vehicles is set as the first transport vehicle (or starting point).

[0096] Considering the example of FIG. 1B, for example, the group of transporting vehicles GV2 is selected, and the transporting vehicle v5 capable of loading cargo, which is located most upstream among the group of transporting vehicles GV2, is set as the first transporting vehicle (or starting point).

[0097] In the method of setting the starting point of the first modification, the group of transport vehicles GV2 can be allocated efficiently. This method allows more efficient allocation than the conventional method of "allocating the transport vehicles to the nearest stations in the order in which transport requests are generated at the stations." However, according to the first method of setting the starting point in steps S101 to S106 of FIG. 2, the setting of the starting point that aims at the overall optimization can be performed.

[0098] As a second variation of the method for setting the first starting point, instead of steps S104 and S105, a group of stations for which a transfer request is made is arbitrarily selected. Then, instead of step S106, the station for which a transfer request is made that is the most downstream of the selected group of stations is set as the first station (or starting point).

[0099] Considering the example of FIG. 1B, for example, station group GST2 is selected, and station ST12, which is the most downstream station in station group GST2 and has a transfer request, is set as the first station (or starting point).

[0100] In the method of setting the starting point of the modified example 2, vehicles can be allocated efficiently to the group of stations GST2. This allows more efficient allocation than the conventional method of "allocating vehicles to the closest stations in the order in which transportation requests are generated at the stations." However, according to the method of calculating the ratio value R2 described in the first method of setting the starting point in steps S101 to S106 of FIG. 2, it is possible to set the starting point with the aim of optimizing the whole.

[0101] 2. Second embodiment The configuration of the transport vehicle system 100a of the second embodiment is the same as that of the transport vehicle system 100 of the first embodiment, except that there are four transport vehicles, as shown in FIG. 5A. However, with regard to the transport vehicles, one transport vehicle v3 is loaded with goods (it cannot be loaded immediately). The configuration of stations ST1 to ST12 of the second embodiment is the same as that of stations ST1 to ST12 of the first embodiment. However, the difference is that while in the first embodiment, the stations with transport requests were stations ST2, ST4, ST6, ST8, ST11, and ST12, in the second embodiment, stations ST2 and ST8 are no longer stations with transport requests.

[0102] For the carrier system 100a in FIG. 5A, a starting point is set, and a carrier capable of carrying a transport is allocated to a station having a transport request.

[0103] First, set the starting point. Here, the starting point is set using the second starting point setting method (Figure 4).

[0104] First, the station having the transportation request, the transportation vehicle and its position are identified.

[0105] In FIG. 5A, the stations having the transport request are stations ST4, ST6, ST11, and ST12.

[0106] In the first embodiment, there is no transport vehicle loaded with an article (not capable of transporting an article). Alternatively, the position of a transport vehicle capable of loading an article is identified while ignoring the transport vehicle loaded with an article. Here, the position of the transport vehicle is identified including the transport vehicle loaded with an article (S121).

[0107] The position of the transport vehicle is determined by considering the shortest possible stopping position of the transport vehicles that can be transported, as in the first embodiment. In the case of Fig. 5A, the shortest possible stopping position of the transport vehicles v1, v2, and v4 is the position of the transport vehicles shown by the dashed lines in Fig. 5B.

[0108] The position of the transport vehicle v3 loaded with the goods is assumed to be the station ST3 where the transport vehicle v3 is scheduled to unload the goods. Then, it is assumed that the transport vehicle v3 loaded with the goods will become the transport vehicle v3 capable of loading the goods at the position where the goods are unloaded in the future.

[0109] Next, the stations and the transport vehicles with the transport request are scored. As in the first embodiment, an origin O is first set at an arbitrary point on the circular route L, and 0 points are assigned to the origin O (S122). Scores are assigned to the transport vehicles capable of loading and the stations with the transport request in order from the origin O to the upstream side (S123). Specifically, when there is a transport vehicle capable of loading on the upstream side from the origin O, +1 point is added, and the added point is assigned to the transport vehicle. When there is a station with the transport request on the upstream side, -1 point is added, and the added point is assigned to the station. The transport vehicle with the highest score is set as the starting point. In the second embodiment, even for the transport vehicles loaded with goods, the transport vehicle v3 is assumed to be at the position of the station where the goods are to be unloaded, and the scores are assigned as if it is a transport vehicle capable of loading.

[0110] In the example of FIG. 5B, starting from the origin O, the first transport vehicle v2 capable of loading is given +1 point. Next, since there is station ST12 with a transport request on the upstream side, +1-1=0 point is given. Continuing this upstream, in order, station ST11 with a transport request is given -1 point, transport vehicle v4 capable of loading is given 0 point, station ST6 with a transport request is given -1 point, station ST4 with a transport request is given -2 points, transport vehicle v3 scheduled to unload is given -1 point, and transport vehicle v1 capable of loading is given 0 point. Therefore, in the case of FIG. 5B, the transport vehicle capable of loading with the highest score is transport vehicle v2. In this case, the starting point is set to transport vehicle v2 capable of loading (S124).

[0111] Next, in the same manner as in the first embodiment, a first allocation method (Figure 3) is used to allocate a transport vehicle capable of loading (including a transport vehicle that is currently loaded with goods but is scheduled to become a transport vehicle capable of loading after unloading in the future) to the station for which a transport request has been made.

[0112] The first allocation method is a method in which, for a station where a transportation request is made, a transport vehicle capable of loading is allocated upstream, starting from the starting point or the first station near the starting point, and then starting from the closest transport vehicle capable of loading (called the second transport vehicle) upstream from the starting point.

[0113] In the example of Fig. 5B, first, the second transport vehicle v4 is assigned to the first station ST12, which is the starting point or close to the starting point (S111). Next, the transport vehicle v3, which is upstream of the second transport vehicle v4 and is scheduled to unload, is assigned to the station ST11, which has a transport request, upstream of the first station ST12 (S112). Similarly, the transport vehicle v1, which can load, is assigned to the station ST6, which has a transport request (S113), and then the transport vehicle v2, which can load, is assigned to the station ST4, which has a transport request, and the assignment is completed (S120).

[0114] According to the allocation of the present embodiment, transportation can be allocated so that the upstream transport vehicle is not made to wait due to the loading of the downstream transport vehicle. However, it should be noted that if the upstream transport vehicle is able to perform operations such as unloading in accordance with the transportation request while the downstream transport vehicle is loading, the upstream transport vehicle is not made to wait.

[0115] In this embodiment, the case where the first allocation method is applied has been described, but the second allocation method can also be applied.

[0116] Although one embodiment of the present invention has been described above, the present invention is not limited to the above embodiment, and various modifications are possible without departing from the spirit of the invention. In particular, the multiple embodiments and modifications described in this specification can be arbitrarily combined as necessary.

[0117] In the first and second embodiments, the stations are assigned to the transport vehicles. However, the transport request (or the transport command) may be assigned to the transport vehicle by referring to the station included in the transport request (or the transport command).

[0118] 3. Summary of the First and Second Embodiments In summary, the transport vehicle system of the present disclosure has the following features.

[0119] The transport vehicle system 100, 100a of the present disclosure includes a circuit path L, a plurality of transport vehicles v, a plurality of stations ST, and a vehicle allocation controller 10. The transport vehicles v can be loaded with goods and travel one way along the circuit path L. The plurality of transport stations ST are arranged along the circuit path L and can load, unload, or both load and unload the plurality of transport vehicles v. The vehicle allocation controller 10 allocates the stations ST with a plurality of transport requests to the plurality of transport vehicles v that can be loaded.

[0120] In the allocation, the starting point is set first, and then the allocation is performed.

[0121] There are two ways to set the starting point.

[0122] The first starting point setting method is as follows, as shown in the flowchart of FIG.

[0123] First, a station ST with a transfer request, a transport vehicle v capable of loading, and its position are identified (S101). Next, a plurality of transport vehicles v capable of loading on the circulation route L are classified into a group of transport vehicles that are continuous on the circulation route L without including a station ST with a transfer request therebetween (S102). Also, the station ST with a transfer request is classified into a group of stations that are continuous on the circulation route L without including a transport vehicle v capable of loading therebetween (S103). Next, a ratio value R1 is calculated by dividing the number of transport vehicles capable of loading in the transport vehicle group by the number of stations with a transfer request in the station group closest to the downstream side of the transport vehicle group (S104). The transport vehicle group with the largest ratio value R1 is selected (S105). The transport vehicle v that is most upstream capable of loading in the selected transport vehicle group is set as the starting point as the first transport vehicle (S106).

[0124] The second starting point is set as follows, as shown in the flow chart of FIG.

[0125] As in the first method, first, a station ST with a transfer request, a transport vehicle v capable of loading, and its position are identified (S121). Next, an arbitrary point on the transport route is set as the origin O, and 0 points are assigned to the origin O (S122). If there is a transport vehicle v capable of loading upstream from the origin O, +1 point is added, and the added point is assigned to the transport vehicle. If there is a station ST with a transfer request upstream, -1 point is added, and the added point is assigned to the station ST. Among all the transport vehicles v capable of loading, the transport vehicle v with the highest score is set as the first transport vehicle and the starting point (S124).

[0126] Regardless of whether the first or second starting point setting method is used, even if there are a plurality of groups of continuous transport vehicles capable of loading cargo on the circuit route, it is possible to set an optimal starting point for the entire circuit route. In other words, it is possible to set a better starting point than when focusing on one group arbitrarily selected from a plurality of transport vehicle groups.

[0127] The starting point may be set to the first transport vehicle determined as described above, or to the first station upstream of the first transport vehicle that has the closest transport request, or to the circular route between the first transport vehicle and the first station.

[0128] When identifying stations with transfer requests in step S101 or S121, not only stations with current transfer requests but also stations for which transfer requests will occur in the near future are included in the stations with transfer requests. By adding transfer requests predicted to occur in the near future to the starting point calculation, frequent recalculation can be prevented.

[0129] The position of the transporting vehicle available for loading in step S101 or S121 is not the current position, but a position downstream from the current position where the transporting vehicle can stop in the shortest time.

[0130] In step S101 or S121, when a transport vehicle loaded with goods is taken into consideration, the starting point is set and allocation is performed assuming that the transport vehicle is located at the station where the goods are unloaded.

[0131] After the starting point is set, there are two methods for allocating a station ST having multiple transport requests to multiple transport vehicles v capable of loading cargo.

[0132] The first allocation method is the method shown in the flowchart of FIG.

[0133] In the first allocation method, first, the second transport vehicle that is closest to the starting point and capable of loading is allocated to the first station that is at or near the starting point (S111). Next, the transport vehicle that is upstream of the second transport vehicle and capable of loading is allocated to the station that has a transport request upstream of the first station (S112). Next, the next upstream transport vehicle that is capable of loading is allocated to the station that has a transport request upstream (S113). The allocation is repeated until there are no more stations with transport requests or transport vehicles that are capable of loading (S114), and then the allocation ends.

[0134] Next, the second allocation method is as follows.

[0135] First, the station (second station) that is closest downstream from the starting point and has a transportation request is assigned to the first transporting vehicle that is at or near the starting point. Next, the allocation is repeated until there are no more transporting vehicles that can be loaded or stations with transportation requests for transporting vehicles downstream of the first transporting vehicle, and then the allocation ends.

[0136] In either the first or second allocation method, transportation can be allocated so that upstream transport vehicles are not kept waiting due to loading of cargo on downstream transport vehicles.

[0137] The setting of the starting point and the allocation may be performed whenever a station with a transportation request or a transportation vehicle capable of loading is changed. When performing reallocation, the allocation is performed including transportation requests that have been allocated once but have not yet been loaded.

[0138] By performing reallocation in this manner, transportation can be more reliably allocated so as to prevent an upstream transportation vehicle from having to wait. [Industrial Applicability]

[0139] The carrier system of the present disclosure can be used as a part of an automated warehouse system in logistics. In a factory, the carrier system can be introduced into a system for transporting parts and products. For example, the carrier system can be applied to a system for transporting semiconductor wafers. [Explanation of symbols]

[0140] 100, 100a Transport Vehicle System 10 Dispatch Controller L Circular Route v1~v6 Transport vehicle GV1, GV2 A group of consecutive loadable vehicles GST1, GST2 A group of stations with consecutive transport requests Stations ST1-12 R1, R2 ratio value

Claims

1. A transport vehicle system, A circular route, A plurality of transport vehicles capable of carrying articles and traveling in one direction along the circular route; a plurality of stations arranged along the circular path and capable of loading or unloading the plurality of transport vehicles; a vehicle dispatch controller that assigns a plurality of stations having transportation requests to a plurality of vehicles capable of loading cargo; Equipped with The dispatch controller, A starting point is obtained based on the positions of all stations having transportation requests and the positions of all transport vehicles available for loading within the circular route; The starting point is (1) A station that has a transport request; (2) A vehicle capable of carrying cargo; or (3) A circular route between the station with the transportation request and the nearest downstream transport vehicle that can load the cargo. When the station with the transportation request set as the starting point is the first station and the transport vehicle that can be loaded set as the starting point is the first transport vehicle, Allocating a transport vehicle capable of loading a load to a station having a transport request in order from the first station to the upstream side in order from a second transport vehicle capable of loading a load that is closest to the upstream side of the starting point, or allocating stations having a transportation request downstream to the transporting vehicle capable of loading the cargo, in order from the first transporting vehicle downstream, starting from the second station having a transportation request that is closest downstream from the starting point; Transport vehicle system.

2. A transport vehicle system, A circular route, A plurality of transport vehicles capable of carrying articles and traveling in one direction along the circular route; a plurality of stations arranged along the circular path and capable of loading or unloading the plurality of transport vehicles; a vehicle dispatch controller that assigns a plurality of stations having transportation requests to a plurality of vehicles capable of loading cargo; Equipped with The dispatch controller, A starting point is obtained based on the positions of a plurality of stations having transportation requests and the positions of a plurality of transport vehicles capable of loading cargo; The starting point is (1) A station that has a transport request; (2) A vehicle capable of carrying cargo; or (3) A circular route between the station with the transportation request and the nearest downstream transport vehicle that can load the cargo. When the station with the transportation request set as the starting point is the first station and the transport vehicle that can be loaded set as the starting point is the first transport vehicle, Allocating a transport vehicle capable of loading a load to a station having a transport request in order from the first station to the upstream side in order from a second transport vehicle capable of loading a load that is closest to the upstream side of the starting point, or Allocating stations having a transportation request downstream to the transport vehicle capable of loading the cargo, in order from the first transport vehicle downstream, starting from the second station having a transportation request that is closest downstream from the starting point, in order; Classifying the plurality of loadable transport vehicles on the circular route into a group of transport vehicles that are continuous on the circular route without including a station having a transport request therebetween, and setting the loadable transport vehicle on the most upstream side among the loadable transport vehicles of one of the transport vehicle groups as the first transport vehicle; or or the stations for which the transport request is made are classified into groups of consecutive stations on the circular route without including any transport vehicle capable of loading cargo therebetween, and the station for which the transport request is made on the most downstream side among the stations for which the transport request is made in one of the groups of stations is designated as the first station; Transport vehicle system.

3. A transport vehicle system, A circular route, A plurality of transport vehicles capable of carrying articles and traveling in one direction along the circular route; a plurality of stations arranged along the circular path and capable of loading or unloading the plurality of transport vehicles; a vehicle dispatch controller that assigns a plurality of stations having transportation requests to a plurality of vehicles capable of loading cargo; Equipped with The dispatch controller, A starting point is obtained based on the positions of a plurality of stations having transportation requests and the positions of a plurality of transport vehicles capable of loading cargo; The starting point is (1) A station that has a transport request; (2) A vehicle capable of carrying cargo; or (3) A circular route between the station with the transportation request and the nearest downstream transport vehicle that can load the cargo. When the station with the transportation request set as the starting point is the first station and the transport vehicle that can be loaded set as the starting point is the first transport vehicle, Allocating a transport vehicle capable of loading a load to a station having a transport request in order from the first station to the upstream side in order from a second transport vehicle capable of loading a load that is closest to the upstream side of the starting point, or Allocating stations having a transportation request downstream to the transport vehicle capable of loading the cargo, in order from the first transport vehicle downstream, starting from the second station having a transportation request that is closest downstream from the starting point, in order; classifying the plurality of loadable transport vehicles on the circular route into a group of continuous transport vehicles on the circular route without including any station having a transport request therebetween; classifying the stations for which the transportation request is made into a group of consecutive stations on the circular route without including a transporting vehicle capable of loading cargo therebetween; A first ratio is calculated by dividing the number of vehicles capable of loading cargo in the group of vehicles by the number of stations having a transportation request in the group of stations downstream closest to the group of vehicles, and the most upstream vehicle capable of loading cargo in the group of vehicles having the largest first ratio is selected as the first vehicle; or a second ratio is calculated by dividing the number of stations in the group of stations with a transport request by the number of vehicles capable of loading cargo in the group of vehicles that is the closest to the group of stations upstream; and the station with the transport request that is the most downstream among the group of stations with the largest second ratio is designated as the first station. Transport vehicle system.

4. A transport vehicle system, A circular route, A plurality of transport vehicles capable of carrying articles and traveling in one direction along the circular route; a plurality of stations arranged along the circular path and capable of loading or unloading the plurality of transport vehicles; a vehicle dispatch controller that assigns a plurality of stations having transportation requests to a plurality of vehicles capable of loading cargo; Equipped with The dispatch controller, A starting point is obtained based on the positions of a plurality of stations having transportation requests and the positions of a plurality of transport vehicles capable of loading cargo; The starting point is (1) A station that has a transport request; (2) A vehicle capable of carrying cargo; or (3) A circular route between the station with the transportation request and the nearest downstream transport vehicle that can load the cargo. When the station with the transportation request set as the starting point is the first station and the transport vehicle that can be loaded set as the starting point is the first transport vehicle, Allocating a transport vehicle capable of loading a load to a station having a transport request in order from the first station to the upstream side in order from a second transport vehicle capable of loading a load that is closest to the upstream side of the starting point, or Allocating stations having a transportation request downstream to the transport vehicle capable of loading the cargo, in order from the first transport vehicle downstream, starting from the second station having a transportation request that is closest downstream from the starting point, in order; The setting of the starting point is An arbitrary point on the conveying path is set as an origin, and the origin is assigned a value of 0; When there is a transport vehicle capable of loading cargo on the upstream side of the transport route from the origin, +1 point is added, and the added point is given to the transport vehicle. When there is a station with a transport request on the upstream side, -1 point is added, and the added point is given to the station. Among all the vehicles capable of loading cargo, the vehicle with the highest score will be the first vehicle. Transport vehicle system.

5. When the dispatch controller performs allocation again after performing allocation once, the dispatch controller performs allocation including transportation requests that have been allocated once but have not yet been loaded. The transport vehicle system according to any one of claims 1 to 4.

6. When setting the starting point, the dispatch controller adds a transportation request predicted to occur in the near future to the starting point calculation. The transport vehicle system according to any one of claims 1 to 5.

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