JP3456580B2 - Car carrier system and its operation method - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a carrier system and a method of operating the same, and more particularly to predicting a time from reservation of a carrier to completion of the carrier.

[0002]

2. Description of the Related Art There are unmanned guided vehicle systems, guided vehicle systems, overhead traveling vehicle systems, and the like as guided vehicle systems. All of these systems manage a plurality of guided vehicles by a system controller and issue a transportation command to the guided vehicles. Allocations and reports of transportation results are received from the transportation vehicles. In the transport vehicle system, the time from assignment of the transport command to the completion of transport is important. This is because the host controller etc. that requests the system controller to transport, based on the estimated transport completion time,
This is because the transfer destination is instructed to prepare for the next work.

[0003]

2. Description of the Related Art In the conventional transport vehicle system, the transport time is predicted based on the travel time based on the distance between the transport source and the transport destination, the actual travel time during the test travel, and the like. However, such predictions have turned out to be uncertain.

[0004]

SUMMARY OF THE INVENTION An object of the present invention is to make it possible to predict the time from the reservation of a transfer to the completion of the transfer as highly reliable data. An additional object of the invention of claim 2 is to make it possible to predict the time with high accuracy. An object of the invention of claim 3 is to accurately predict the time until the completion of conveyance.

[0005]

The transport vehicle system of the present invention is provided with a system controller and a plurality of transport vehicles. The system controller receives a transport request from the outside and assigns a transport command to the transport vehicle. A system for reporting a transfer result, wherein the system controller is provided with an average time from transfer reservation to completion of transfer, a combination of a transfer source and a transfer destination, and two factors of a reserved transfer command. It is characterized in that means is provided for obtaining the traffic added average time for each time (claim 1).

[0006] The traffic weighted average is the transport source (at the departure point of the transport vehicle, called "FROM data" or simply "FROM")
And the destination (“TO data” or simply “TO” at the destination of the vehicle) and the number of delivery reservations, 2
Calculate for each factor. Other than this, for example, there is a simple average that does not consider the number of transport reservations. The type of average may be a simple average or a weighted average with some weight added. Preferably, the traffic-added average time for each of the two factors of the combination of the transfer source and the transfer destination and the number of reserved transfer commands, and the simple average result ignoring the number of transfer reservations for each combination of the transfer source and the transfer destination Two types of average time are calculated (Claim 2).

In the method for operating a carrier system according to the present invention, a plurality of carriers are managed by a system controller, the system controller assigns a carrier command to the carrier in response to a carrier request from the outside, and the carrier is the system controller. A method of operating a system for reporting a transfer result, wherein the system controller is a simple average actual time that ignores the number of transfer reservations for each combination of a transfer source and a transfer destination, and a transfer source and a transfer destination. Traffic-added average time considering the number of reserved transfer commands for each combination of
The required time from the reservation of the two types of transportation to the completion of transportation is obtained (claim 3).

[0008]

According to the invention of claim 1, as the average time from the reservation of the conveyance to the completion of the conveyance, the combination of the conveyance source and the conveyance destination and the number of the reserved conveyance instructions are set for each of two factors. , Calculate the traffic-added average time. This time is a time based on the actual processing result of the transfer command, and is not a simple time calculated from the traveled distance, nor is it a time calculated during the trial operation before the actual operation of the transfer system is started. Furthermore, the traffic-added average time is an average required time that reflects the actual condition of the transportation system, and is a reliable prediction time that takes into account the influence of the number of reserved transportation cases.
Therefore, in the present invention, it is possible to accurately obtain the time until the completion of conveyance.

According to the second aspect of the present invention, the traffic-added average time in which the number of reserved transfer commands is added for each combination of the transfer source and the transfer destination, and the number of transfer reservations is ignored for each combination of the transfer source and the transfer destination. Then, two types of average required times, that is, the simple average actual time, are calculated. Of these, the simple average actual time is such that when the operation of the transport vehicle system is started, data is collected so that the average can be obtained in a relatively short period of time, and the average can be obtained from the initial operation. On the other hand, the traffic-added average time is more reliable data, but data for obtaining the average cannot be collected until a certain period of time has passed since the operation of the transport system was started. However, the average traffic-added time increases as the system continues to operate, and reliable data can be obtained as the system continues to operate. Therefore, in the second aspect of the invention, two types of predicted required times are calculated, that is, a simple average actual time that does not consider the number of reserved transportation commands and a traffic-added average time that considers the number of reserved transportation commands. In the initial period of, etc., the simple average actual time is used, and when the operation is continued, the more reliable predicted required time is used by using the traffic added average time, or the simple average actual time and traffic added average time are used depending on the use of the estimated required time. Can be used properly.

According to the third aspect of the present invention, the system controller obtains a simple average time ignoring the number of transfer reservations from the transfer reservation to the completion of transfer for each combination of the transfer source and the transfer destination, and determines the transfer source and the transfer destination. The average required time of two types, that is, the traffic-added average time in which the number of the reserved transfer commands is added, is calculated for each combination. Then, when the operation of the transportation system is started, first, the data for obtaining the simple average actual time is collected, and the time required for transportation can be predicted to some extent. When the operation of the transportation system is further continued, data sufficient to calculate the traffic-added average time is collected, and it becomes possible to more accurately predict the required time in consideration of the number of transportation reservations.

[0011]

EXAMPLE An example is shown in FIGS. FIG. 1 shows a layout of a guided vehicle system by taking an automated guided vehicle system as an example. Reference numeral 2 denotes a traveling route, 4 denotes a plurality of guided guided vehicles, and these are managed by a system controller 6. When the system controller 6 communicates with the host controller 8 and accepts a transportation reservation from the host controller 8, the system controller 6 allocates a transportation command to the automatic guided vehicle 4. When the conveyance by the automatic guided vehicle 4 is completed, the completion of the conveyance is reported to the host controller 8. The host controller 8 also inquires of the system controller 6 about the estimated time from the reservation of the conveyance to the completion of the conveyance, and the progress status of the reserved conveyance work. The host controller 8 is
For example, it is a controller that controls the entire production and distribution in a clean room or factory.

There are a plurality of stations ST1 to ST6 along the traveling route 2, and the automatic guided vehicle 4 conveys articles between these stations. Reference numeral 10 denotes an allocating unit, which processes the allocation of the transportation command in the system controller 6, selects one of the plurality of unmanned guided vehicles 4 in the allocation of the transportation command, and selects a departure place (FROM) and a destination (TO). Is designated to instruct the conveyance of the article. The transport reservations received by the system controller 6 are transferred to the allocating unit 10, and the allocating unit 10 stores these transport reservations in a queue, gives them a predetermined priority, and allocates them to the automatic guided vehicle 4. At the same time, the maximum number of transfer commands assigned to each automatic guided vehicle 4 is one, and a plurality of transfer commands are not simultaneously assigned to the automatic guided vehicle 4. That is,
The process of determining which of the transport commands is to be preferentially executed is not performed by the autonomous judgment of the automatic guided vehicle.

The number-of-reservations storage unit 12 stores the number of transportation reservations received from the host controller 8, and deletes the corresponding reservation each time transportation is completed. The guided vehicle position storage unit 14 stores the current position of the unmanned guided vehicle 4 and is used as a reference when the allocating unit 10 allocates a carrying command to the unmanned guided vehicle 4. The actual result table 16 stores the actual result of the required transportation time for each combination of the departure place and the destination (“FROM” and “TO”). Record 1 for the combination of one departure point and one destination in the record 16
Indicated as 8, T1 is the time when the reservation of the transport is accepted from the host controller 8, T2 is the time when the transport command is assigned to the automatic guided vehicle by the allocating unit 10, and T3 is the time when the transport command is finished. is there. In addition, n is the number of reservations of other accepted transports at the time of accepting the transport reservation.

Reference numeral 20 denotes a simple average actual time calculating unit, which sorts the actual result table 16 for each combination of "FROM" and "TO", and simply averages the difference between the completion time T3 and the reservation time T1 to reserve the transportation. Calculate the average time required to complete after receiving. The characteristic of this required time is that it does not take into account the amount of work applied to the automated guided vehicle system. And this means that the number of reservations is ignored and a simple average is calculated. The traffic-added actual time calculating unit 22 calculates the traffic-added average time in which the traffic situation is added,
This sorts the data in the performance table 16 for each combination of “FROM” and “TO” and for each number of reservations n, and the time required for the same reservation from “FROM” to “TO” (time The difference between T3 and time T1) is averaged. The average traffic-added time thus obtained takes into account the influence of the traffic situation of the automatic guided vehicle system, that is, the number of reserved transportation cases, and is a more reliable prediction time.

In order to obtain the traffic-added average time, it is necessary to obtain a considerable number of transportation records for each combination of the starting point and the destination. For this reason, it takes some days from the start of operation of the automated guided vehicle system to obtain the traffic-added average time as reliable data. Therefore, if it is necessary to obtain the traffic-added average time in a shorter number of days from the start of operation of the automated guided vehicle system, the regression analysis unit 23 may be provided. In the regression analysis unit 23, for example, the combination of the starting point and the destination is set as one factor, the number of reserved transportation items is set as another factor, and the traffic-added average time is obtained by multiple regression analysis for the two factors.

In the actual result table 16, the required time is recorded not as the destination from the current position of the unmanned guided vehicle 4 but as the starting point for the station for loading in the carrying work and the destination for the station for unloading. On the other hand, when the number of reserved transportation is small on average, the record table 16 may be configured for the combination of the current position and the destination of the automatic guided vehicle to be allocated. However, this makes it difficult to perform processing because it is necessary to predict which unmanned guided vehicle the vehicle will be assigned to when the transportation reservation is accepted. In addition, when the automatic guided vehicle fails during operation of the automatic guided vehicle system or when other trouble occurs, it is preferable not to use the related transportation instruction to calculate the simple average actual time or the traffic added average time. .

FIG. 2 shows a procedure from the reservation of the transportation to the updating of the result table for one transportation instruction. When the host controller inquires from the system controller about the required transfer time for scheduling,
The system controller responds to the host controller with the simple average actual time for the transfer work. If you have a reservation for transportation immediately when you answer the inquiry,
Although the traffic-added average time is valid, there is no guarantee that there will be a reservation for transport immediately for the response.In such a case, if the traffic-added average time is used, many other transport reservations will be accepted before the transport reservation. In this case, the reliability of the required time will be reduced.

Subsequently, when the transfer reservation is accepted from the host controller, the data in the reservation number storage unit is incremented by 1,
A transportation reservation is added to the queue of the allocating unit 10. Then, the transport reservation time T1 is described in the column of the combination of the corresponding starting point and destination in the actual result table 16. The allocating unit 10 allocates the transportation command corresponding to the automatic guided vehicle, and based on this, records the allocation time T2 in the performance table 16. When the transfer instruction is completed, the automatic guided vehicle reports the fact to the system controller, the completion time T3 is described in the performance table 16, and the host controller is notified that the transportation is completed. In the calculation of the simple average actual time, the actual result table is sorted for each starting point and destination, and the simple average actual time is calculated. Further, in the calculation of the traffic-added average time, the result table is sorted by the combination of the departure place and the destination and the number of reservations, and the traffic-added average time is calculated.

FIG. 3 schematically shows the calculation of the actual time. FIG. 3 shows the time from the reservation of the transfer to the completion of the transfer from the station A to the station B for each reservation number. In the simple average actual time, each data in FIG. 3 is simply averaged. In the traffic-added average time, the data in FIG. 3 is organized for each number of reservations and the average is calculated for the corresponding number of reservations.

FIG. 4 shows the calculation of the traffic added average time using the regression analysis. The simple average actual time without considering the number of reservations is data that can be easily obtained, and it is not necessary to perform regression analysis. The horizontal axis of FIG. 4 is the number of reservations, and the vertical axis is the station of the departure place when the destination is fixed to the station N. Here, the stations A to M are considered as stations of departure, and the station M is closest to the destination station N, and the station A is the farthest. During this period, the stations are sequentially arranged according to the travel distance from the destination station N. . The time from transfer reservation to completion is recorded as data for each combination of the station of departure and the number of reservations. In FIG. 4, points with data are indicated by ●. In this way, by multiple regression analysis with the number of reservations as one factor and the station at the departure place as another factor, even if the number of data is small, the combination of the destination station and the station at the departure place,
Also, it is possible to calculate the traffic-added average time for the two factors of the number of reservations.

In the embodiment, since the two average required times, that is, the simple average actual time and the traffic-added average time, are obtained, the time from the reservation of transport to the completion can be reliably predicted. As for the highly reliable average traffic-added time, the more the data is collected as the operation of the automatic guided vehicle system is continued, the more reliable data can be obtained. In the example,
Although the automatic guided vehicle system is operated by using both the simple average actual time and the traffic added average time, only the traffic added average time may be used to simplify the system.

[Brief description of drawings]

FIG. 1 is a block diagram showing a configuration of a carrier vehicle system according to an embodiment.

FIG. 2 is a flowchart showing a process from an inquiry about a transfer time to an update of transfer required time data in the embodiment.

FIG. 3 is a diagram showing a method of calculating a simple average actual time and a traffic-added average time in the embodiment.

FIG. 4 is a diagram showing a method of calculating a traffic-added average time by regression analysis in a modified example.

[Explanation of symbols]

2 travel routes 4 Automated guided vehicles 6 system controller 8 Host controller 10 Allocation section 12 Number of reservations storage 14 Transport vehicle position storage unit 16 achievement list 18 records 20 Simple average actual time calculation unit 22 Traffic addition actual time calculation unit 23 Regression Analysis Department

─────────────────────────────────────────────────── --Continued from the front page (56) Reference JP-A-10-214115 (JP, A) JP-A-11-309650 (JP, A) JP-A-11-330197 (JP, A) JP-A-60- 204015 (JP, A) JP 62-85305 (JP, A) JP 5-94212 (JP, A) JP 2001-344019 (JP, A) (58) Fields investigated (Int. Cl. ⁷⁾ , DB name) G05D 1/02

Claims (3)

(57) [Claims] 1. A system controller and a plurality of transport vehicles are provided, the system controller receives a transport request from the outside and assigns a transport command to the transport vehicle, and the transport vehicle reports the transport result to the system controller. In the system, the system controller causes the average time from the reservation of the transfer to the completion of the transfer to be a traffic-added average time for each of two factors, that is, the combination of the transfer source and the transfer destination and the number of reserved transfer commands. A transport vehicle system characterized by being provided with a means for obtaining. 2. The transporting method according to claim 1, wherein, in addition to the traffic-added average time, a simple average actual time that ignores the number of transport reservations is calculated for each combination of transport source and transport destination. Car system. 3. A system in which a plurality of transport vehicles are managed by a system controller, the system controller allocates a transport command to the transport vehicles in response to a transport request from the outside, and the transport vehicles report the transport results to the system controller. In the operation method of the above, the system controller sends a simple average actual time ignoring the number of transfer reservations for each combination of the transfer source and the transfer destination, and a transfer command reserved for each combination of the transfer source and the transfer destination. A method for operating a carrier system, characterized in that a required time from the reservation of two types of transportation to the completion of transportation is calculated, that is, the average time taken into consideration of traffic considering the number.