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CN-122003649-A - Driving vehicle system

CN122003649ACN 122003649 ACN122003649 ACN 122003649ACN-122003649-A

Abstract

The transport vehicle system includes a plurality of transport vehicles traveling along a transport path and a transport vehicle controller that controls traveling of the transport vehicles. The transport vehicle controller includes a route determination unit that determines a travel route of the transport vehicle based on connection route costs of each of a plurality of connection routes, a selection unit that selects a target connection route that is predicted to have future availability exceeding a predetermined criterion from the plurality of connection routes, and a cost change unit that calculates an index value indicating the concentration easiness of the transport vehicle for each of a plurality of upstream connection routes that exist in a predetermined upstream range with an upstream junction closest to the target connection route as a starting point, and preferentially selects an upstream connection route having a high index value as one or more bottleneck connection routes, and increases the connection route costs of the one or more bottleneck connection routes.

Inventors

  • INOMOTO SHINICHIRO

Assignees

  • 村田机械株式会社

Dates

Publication Date
20260508
Application Date
20240704
Priority Date
20231212

Claims (5)

  1. 1. A travel vehicle system includes a plurality of travel vehicles that travel along a predetermined travel path, and a controller that controls travel of the travel vehicles by distributing a travel instruction that instructs travel to a predetermined point on the travel path to the travel vehicle selected from the plurality of travel vehicles, The travelling car system is characterized in that, The travel path includes a plurality of nodes including branching portions and joining portions, and a plurality of connection paths connecting the nodes, The controller has: a storage unit that stores a layout of the travel route and link route costs associated with each of the plurality of link routes; A route determination unit that preferentially determines, as a travel route of the travel vehicle, a candidate route having a smaller sum of the link route costs of a plurality of link routes included in a candidate route among a plurality of candidate routes of the travel vehicle for executing the travel instruction, based on the link route costs of the plurality of link routes; A selection unit for selecting a target connection path from the plurality of connection paths, the target connection path being expected to have future availability exceeding a predetermined reference, and And a cost changing unit that acquires an index value indicating a concentration easiness of the traveling vehicle for each of a plurality of upstream connection paths existing in a predetermined upstream range from an upstream junction closest to the target connection path among the plurality of connection paths, and preferentially selects the upstream connection path having the index value higher than the index value as one or more bottleneck connection paths, and increases the connection path cost of the one or more bottleneck connection paths.
  2. 2. The traveling car system according to claim 1, wherein, The cost changing unit calculates the index value of each of the plurality of upstream link paths based on a graph theory.
  3. 3. The traveling car system according to claim 1, wherein, The selecting unit repeatedly performs a process of selecting the target link path at predetermined time intervals, The cost changing unit performs processing of selecting the one or more bottleneck connection paths and increasing the connection path cost of the one or more bottleneck connection paths each time the target connection path is selected by the selecting unit.
  4. 4. The traveling car system according to claim 1, wherein, As for the selection portion, a plurality of selection portions are provided, For each of the plurality of connection paths, a maximum allowable number representing a maximum number of the traveling vehicles that can simultaneously exist in the connection path is acquired, And selecting, as the target link path, a link path having a number of traveling vehicles existing in the link path equal to or greater than a predetermined proportion of the maximum allowable number of the link path.
  5. 5. The traveling car system according to claim 1, wherein, The travel instruction is associated with a destination included in any one of the plurality of connection paths, The controller controls the travel of the travel vehicle in such a manner that the travel vehicle to which the travel instruction is assigned is directed to the destination, The selection unit calculates, for each of the plurality of connection paths, the number of travel instructions associated with each of the plurality of connection paths predicted to be generated in the future based on the number of past travel instructions for which the destination is set as the point included in the connection path, and selects the target connection path based on the number of travel instructions calculated for each of the plurality of connection paths.

Description

Driving vehicle system Technical Field The present disclosure relates to a travel car system. Background Conventionally, a traveling vehicle system is known that controls traveling of a traveling vehicle that conveys articles such as FOUP (Front Opening Unified Pod) accommodating a semiconductor substrate in a semiconductor manufacturing factory or the like (see patent document 1). Patent document 1 describes a method of setting a travel path of a traveling vehicle based on a connection path cost set for each connection path on a predetermined travel-possible path. Patent document 1 Japanese patent No. 7059999 In the above-described method, there is a case where a route that bypasses the target connection route is easily selected by increasing the connection route cost of the connection route (hereinafter, referred to as "target connection route") predicted to have high availability, thereby suppressing occurrence of traffic jam in the target connection route. However, if the link cost of the target link is merely increased as described above, the occurrence of traffic congestion in the traveling vehicle system may not be adequately suppressed. Disclosure of Invention It is therefore an object of the present disclosure to provide a traveling vehicle system capable of effectively suppressing the occurrence of traffic jams. The present disclosure includes the traveling vehicle systems of [1] to [5 ]. [1] A travel vehicle system includes a plurality of travel vehicles that travel along a predetermined travel path, and a controller that controls travel of the travel vehicles by distributing a travel command to a travel vehicle selected from the plurality of travel vehicles at a predetermined point on the travel path, wherein the travel path includes a plurality of nodes including a branching portion and a joining portion and a plurality of link paths connecting the nodes, the controller includes a storage portion that stores a layout of the travel path and link path costs associated with each of the plurality of link paths, a path determination portion that preferentially determines a candidate path having a smaller sum of link path costs of the plurality of link paths included in the candidate paths for the travel vehicle as a travel path of the travel vehicle based on the link path costs of each of the plurality of link paths, and a selection portion that preferentially acquires a link path having a higher value than a predetermined point value from the plurality of link paths as a predetermined point value, from a plurality of link paths having a higher value than a predetermined point value, and a plurality of link paths having a higher value than a predetermined point value, as a bottleneck value, and a plurality of link paths having a higher value than a predetermined point value. According to the traveling vehicle system of [1], the link cost of the bottleneck link path in which traveling vehicles are likely to concentrate in the upstream link path in the predetermined upstream side range from the upstream junction closest to the target link path is increased, instead of merely increasing the link cost of the target link path, whereby traffic congestion in the bottleneck link path can be prevented in advance. In other words, it is possible to suppress a situation in which the number of traveling vehicles that use the bottleneck link path in order to reach the target link path at a future time increases greatly (that is, the occurrence of traffic jam in the bottleneck link path). As a result, the occurrence of traffic jams in the traveling vehicle system can be effectively suppressed. [2] In the traveling vehicle system according to [1], the cost changing unit calculates the index value of each of the plurality of upstream link paths based on a graph theory. According to the configuration of [2], the bottleneck connection path in the cost changing unit can be efficiently selected by relatively simple calculation processing. [3] In the traveling vehicle system according to [1] or [2], the selecting unit repeatedly performs a process of selecting the target link path at predetermined time intervals, and the cost changing unit performs a process of selecting the one or more bottleneck link paths and increasing the link path cost of the one or more bottleneck link paths each time the target link path is selected by the selecting unit. According to the configuration of [3], since the combination of the target link path and the bottleneck link path can be appropriately updated at predetermined time intervals, occurrence of traffic jam in the traveling vehicle system can be appropriately suppressed according to a change in the condition of the entire system. [4] In the vehicle system according to any one of [1] to [3], the selecting unit obtains a maximum allowable number indicating a maximum number of vehicles that can exist in a connection path simultaneously for each of the plurality of connection paths, and