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CN-122029496-A - Conveying vehicle system

CN122029496ACN 122029496 ACN122029496 ACN 122029496ACN-122029496-A

Abstract

A transport vehicle system is provided with a plurality of transport vehicles and a transport vehicle controller. The transport vehicle controller includes a prediction unit that acquires prediction information for at least a part of links to be transported, the prediction information having a predetermined numerical range related to future usage, a route determination unit that preferentially determines, as a transport route of the transport vehicle, a candidate route having a smaller sum of link costs of a plurality of links included in the candidate route, among a plurality of candidate routes for causing the transport vehicle to perform predetermined transport, based on link costs of the plurality of links, and a correction unit that corrects the link costs of the links to be transported, based on the numerical range of the prediction information, so that the link costs of the links to be transported change during the plurality of transport.

Inventors

  • INOMOTO SHINICHIRO

Assignees

  • 村田机械株式会社

Dates

Publication Date
20260512
Application Date
20240701
Priority Date
20231212

Claims (10)

  1. 1. A conveyor system is provided with a plurality of conveyor vehicles for conveying articles by traveling along a predetermined travel path, and a controller for controlling the travel of the plurality of conveyor vehicles, The travel route is composed of a plurality of links connected with each other; each of the plurality of links has associated therewith a link cost; The controller has: a prediction unit that obtains, for at least a part of links to be included in the plurality of links, prediction information having a predetermined numerical range related to future use rates; A path determination unit that preferentially determines, as a transport path of the transport vehicle, a candidate path having a smaller sum of link costs of a plurality of links included in the candidate path among a plurality of candidate paths for causing the transport vehicle to perform transport, based on link costs of the plurality of links, respectively, and And a correction unit that corrects the link cost of the target link based on the numerical range of the prediction information so that the link cost of the target link changes in a plurality of conveyances.
  2. 2. The cart system of claim 1, wherein, The controller controls travel of the transport vehicle by assigning, among transport instructions generated in the transport vehicle system, the transport instructions associated with a destination included in the object link to one of the transport vehicles, so that the transport vehicle is moved toward the destination; the future usage is information related to the number of delivery instructions predicted to be generated in the future at a destination included in the subject link.
  3. 3. The cart system of claim 1, wherein, The prediction unit acquires, as the prediction information, information of probability density with which a probability is generated in association with each of a plurality of values related to the future use rate; The correction unit generates a random number based on the probability density, and corrects the link cost of the target link based on a value corresponding to the random number included in the numerical range of the prediction information.
  4. 4. The cart system of claim 3, wherein, The correction unit corrects the link cost of each of the target links based on a ratio of the numerical value of each of the target links to an average value of numerical values determined by the random numbers for each of the plurality of target links.
  5. 5. The cart system of claim 1, wherein, The prediction unit acquires, as the prediction information, information of probability density with which a probability is generated in association with each of a plurality of values related to the future use rate; The range defined by the predetermined probability threshold in the probability density is set as the numerical range of the prediction information.
  6. 6. The cart system of claim 5, wherein, The prediction unit generates a plurality of random numbers from the probability density, and determines the probability threshold based on a distribution of the plurality of random numbers.
  7. 7. The cart system of claim 5, wherein, The correction unit corrects the link cost of the target link based on a ratio of a value selected from the range of values of the prediction information to a mode of the probability density.
  8. 8. The cart system of claim 5, wherein, The controller controls travel of the transport vehicle by assigning, among transport instructions generated in the transport vehicle system, the transport instructions associated with a destination included in the object link to one of the transport vehicles, so that the transport vehicle is moved toward the destination; the prediction unit obtains the probability density based on the number of past delivery instructions whose destination is set at a point included in the target link.
  9. 9. The cart system of claim 5, wherein, The prediction unit obtains the probability density based on history information indicating the number of the transport vehicles that have used the target link in the past.
  10. 10. The cart system of claim 1, wherein, The path determination unit determines whether to use the link cost of the target link corrected by the correction unit based on the priority of conveyance.

Description

Conveying vehicle system Technical Field The present disclosure relates to a conveyor car system. Background Conventionally, a transport vehicle system is known, for example, in a place such as a semiconductor manufacturing factory, which includes a plurality of transport vehicles for transporting articles such as FOUP (Front Opening Unified Pod), which are front opening type wafer cassettes for accommodating semiconductor substrates, and a controller for controlling the travel of these transport vehicles (see patent document 1). Patent document 1 describes a method of setting a conveyance path of a conveyance vehicle based on a link cost set for each link (link) on a predetermined travelable path. Prior art literature Patent literature Patent document 1 Japanese patent No. 7059999 Problems to be solved by the invention In the above-described method, the link cost of each link may be statically set based on factors such as the distance (length) of the link, or may be dynamically set based on factors such as past actual performance (e.g., the average time required for a predetermined number of vehicles that have recently used the link to pass through the link, etc.). In any case, when a plurality of conveyances (conveying instructions) are generated at substantially the same timing, the conveying paths of the respective conveyances are determined under the same conditions (that is, in the state where the link costs set for the respective links are substantially the same). As a result, for example, when the shortest path search is performed by an algorithm such as Dijkstra's method, the same path is easily fixed and selected among a plurality of transmissions. In this way, when a plurality of transmissions occur in a concentrated manner at almost the same time, there is a problem that the utilization rate of a specific path increases and congestion is likely to occur. As a method for avoiding this problem, it is conceivable to apply restrictions to some of the plurality of transmissions generated at the same time, to perform route search without using the specific route, but it is difficult to detect a route causing congestion in advance, and complicated control is required. Disclosure of Invention The purpose of the present disclosure is to provide a conveyor system capable of suppressing congestion caused by a conveyor concentrating on a specific route in a plurality of conveyances by simple control. Means for solving the problems The conveying vehicle system comprises the conveying vehicle systems of [1] to [10 ]. [1] A conveyor system comprising a plurality of conveyor vehicles for conveying articles by traveling along a predetermined travel path, and a controller for controlling the travel of the plurality of conveyor vehicles, The travel route is composed of a plurality of links connected with each other; Each of the plurality of links is associated with a link cost; The controller has: a prediction unit that obtains, for at least a part of links to be included in the plurality of links, prediction information having a predetermined numerical range related to future use rates; A path determination unit that preferentially determines, as a transport path of the transport vehicle, a candidate path having a smaller sum of link costs of a plurality of links included in the candidate path among a plurality of candidate paths for causing the transport vehicle to perform transport, based on link costs of the plurality of links, respectively, and And a correction unit that corrects the link cost of the target link based on the numerical range of the prediction information so that the link cost of the target link changes in a plurality of conveyances. In the above-described conveyor vehicle system according to [1], the link cost of at least a part of the target links included in the travel path is corrected so as to change in a plurality of conveyors. Therefore, even if a plurality of transfers are collectively generated at the same timing, the path search condition (i.e., the link cost of the target link) can be made different in each transfer. As a result, the plurality of transport paths are easily separated into a path using the target link and a path not using the target link. Further, by using a predicted amplitude (numerical range) related to the future use rate, the link cost of the target link can be easily corrected, and a deviation can be brought to the correction result. Therefore, according to the above-described conveyance vehicle system, it is possible to suppress congestion caused by concentration of conveyance vehicles on a specific route in a plurality of conveyances by simple control. [2] In the vehicle system of [1], the controller controls the travel of the vehicle by assigning the transport command associated with a destination included in the object link to one of the transport vehicles among the transport commands generated in the vehicle system so as to move the transport vehicle toward