JP3323821B2 - Automatic guided vehicle control system - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an automatic guided vehicle control system for controlling an automatic guided vehicle for realizing efficient physical distribution.

[0002]

2. Description of the Related Art Conventionally, there has been proposed a control method for assigning a transfer instruction to an automatic guided vehicle on a production line or the like. FIG. 7 is an overall view showing an example of a conventional automatic guided vehicle control system. Automatic guided vehicles A11, A12, A1
3 travels along a closed-loop travel path R11 that cannot pass or pass each other. At this time, every time a transfer instruction is issued, an unmanned guided vehicle that is not performing the work or the loading side devices E11, E12, and E even if the work is being performed.
And a method of allocating a transfer instruction to an unmanned guided vehicle on the upstream side which is the closest from the loading side device to the unmanned guided vehicle which completes the work before reaching the position 13 or E14 (Japanese Patent Laid-Open No. 9-7331).
No. 6) and a method of allocating the oldest transport instruction to an unmanned guided vehicle for which a work instruction has been requested when the home position or wholesale has been completed (Japanese Unexamined Patent Publication No.
No. 44234).

[0003]

By the way, the conventional transfer instruction assignment control method is intended for a closed loop in which the automatic guided vehicles do not pass or pass each other.
It did not assume a traveling route that could be overtaken. Therefore, when the conventional control method is applied to an unmanned guided vehicle on a traveling route that can pass, there is a problem that a transport loss occurs.

[0004] First, every time a transfer instruction described in Japanese Patent Application Laid-Open No. 9-73316 is issued, an unmanned guided vehicle on the upstream side from the loading apparatus that does not have a work instruction or has a work instruction. Consider a method of searching for items to be completed by the loading point in order of decreasing order and assigning instructions. In this case, at the time when the transfer instruction is issued, even if the instruction is assigned to the unmanned transport vehicle closest to the upstream side, on the overtaking traveling route, the unmanned transport vehicle arrives at the loading point first. Not necessarily. While an unmanned guided vehicle is performing a wholesale operation or a charging operation, it may be overtaken by another unmanned guided vehicle, resulting in a transfer loss.

Next, consider a method described in Japanese Unexamined Patent Publication No. 7-44234, in which the oldest uninstructed transport instruction is allocated each time a work instruction is requested from an unmanned transport vehicle at the home position or at a home position. Try. In this case, in order not to make a work instruction request while the unmanned traveling vehicle is traveling,
There are problems such as the inability to assign a transfer instruction from the completion of the work to the arrival at the home position, and the possibility that the traveling distance from the home position to the loading point may become longer.

Further, as a problem common to the above two control methods, since transfer instructions are not assigned based on the tact time of the apparatus or the amount of work in progress, a loss time occurs due to waiting for carry-in or delay in carry-out at the production apparatus. The possibility of doing it is great. In addition, since the wholesaler has no empty shelves and a transfer instruction is assigned even in the case of failure, there is a problem that the wholesaler cannot wholesale from the automatic guided vehicle to the wholesaler.

SUMMARY OF THE INVENTION It is an object of the present invention to efficiently transfer an automatic guided vehicle traveling along a traveling route that can be overtaken, and to issue a transfer instruction in consideration of the operation states of the automatic guided vehicle and the unloading device. To provide an automatic guided vehicle control system capable of performing the following.

[0008]

According to the first aspect of the present invention, there is provided an automatic guided vehicle for automatically transporting a package to a destination according to a transport instruction, a traveling route over which the automated guided vehicle can travel and pass. A loading-side device and an unloading-side device for unloading and unloading the cargo conveyed by the automatic guided vehicle, and at least one or more transport inquiries provided on a traveling route and having an unmanned guided vehicle having no transport instruction and requesting a transport instruction An automatic guided vehicle control system including a point and a transport control device that controls the traveling of the automatic guided vehicle based on the transport instruction request. The transfer control device assigns a transfer instruction that specifies a loading side device and a wholesale side device to be transferred to the unmanned guided vehicle that has issued a transfer instruction request from the transfer inquiry point.

According to a second aspect of the present invention, there is provided the automatic guided vehicle control system according to the first aspect, wherein the transport control device issues a transport instruction starting from a loading side device within a predetermined section close to a transport inquiry point. It is characterized by performing.

According to a third aspect of the present invention, there is provided the automatic guided vehicle control system according to the first or second aspect, wherein the transport control device stores necessary transport instructions, and performs transport from the transport instructions. The transfer instruction having the highest priority level is assigned to the automatic guided vehicle according to the priority.

According to a fourth aspect of the present invention, there is provided the automatic guided vehicle control system according to the third aspect, wherein the transfer priority is based on a tact time and a work-in-progress amount of the loading apparatus and the unloading apparatus. The value is determined, and is changed over time after the issuance of the transport instruction.

According to a fifth aspect of the present invention, there is provided the automatic guided vehicle control system according to any one of the first to fourth aspects, wherein the transport control device determines whether or not the automatic guided vehicle, the loading device, and the wholesale device can operate. It has a function of confirming whether or not it can be operated, and changes to another transport instruction when it cannot be operated.

[0013]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is an overall view showing an automatic guided vehicle control system according to the present invention. This automatic guided vehicle control system includes traveling paths R1, R that can be passed by the automatic guided vehicles A1, A2, A3 and the automatic guided vehicles A1 to A3.
2, R3, buffer stations B1 and B2 for temporarily storing luggage (parts and the like), production apparatuses E1 to E4, transfer inquiry points T1 to T6 at which the automatic guided vehicles A1 to A3 issue a transfer instruction request, and transfer instructions. And a transfer control device 10 for issuing a transfer instruction to the automatic guided vehicles A1 to A3 based on the request.

Here, the traveling route R1 is a closed loop, and buffer stations B1 and B2 for stopping the automatic guided vehicle and production devices E1 to E4 are arranged on the outer periphery thereof. The traveling route R2 is also a closed loop, and the traveling route R
An automatic guided vehicle that is disposed on the inner peripheral side of
It is possible to overtake an unmanned guided vehicle stopped on the traveling route R1. The travel route R3 is a travel route provided between the travel route R1 and the travel route R2, and is used by the automatic guided vehicle to travel along the travel routes R1 and R2. Further, in the buffer stations B1 and B2 and the production devices E1 to E4, ports P1 to P12 in which the unmanned transport vehicles stop and work for loading and unloading the luggage are installed. The transfer inquiry points T1 to T6 are arranged on the traveling route R2.

In the automatic guided vehicles A1 to A3, a device for transmitting a transfer instruction request to the transfer control device 10 when there is no transfer instruction (including when the transfer instruction is completed) is provided. It is not only the transfer inquiry points T1 to T6 that the automatic guided vehicles A1 to A3 make the transfer instruction request,
This is performed even while the vehicle is stopped at ports P1 to P12. Production equipment E1
At E4, a device for transmitting a transfer request for the automatic guided vehicle to the transfer control device 10 when it is necessary to unload and unload the load is installed. The automatic guided vehicles A1 to A3, the buffer stations B1 and B2, and the production devices E1 to E4
A device for checking the operation status and transmitting the status to the transport control device 10 is also installed.

The transport control device 10 includes a transmitting / receiving unit 11 for transmitting information to each device, a control unit 12 for controlling transport,
The storage unit 13 stores each information. Transmitting / receiving unit 11
Are automatic guided vehicles A1 to A3, buffer station B
1, a transfer request between B2 and the production devices E1 to E4,
The control unit 12 receives information such as a transfer instruction request and an operation status.
Send the information to The control unit 12 stores the information in the storage unit 1
In addition to the information stored in No.3, a transfer instruction for the automatic guided vehicles A1 to A3 is created based on the information. Then, a transfer instruction is transmitted from the transmission / reception unit 11 to the automatic guided vehicles A1 to A3.
Send to The information stored in the storage unit 13 is a nearest stack point table shown in FIG. 2, a transport priority table shown in FIG. 3, a transport request list shown in FIG. 4, and a transport instruction candidate list shown in FIG. It will be described later.

Next, an outline of an example of the operation of the automatic guided vehicle control system will be described. The production apparatuses E1 to E4 transmit a transfer request for the automatic guided vehicle to the transfer control apparatus 10 when it becomes necessary to unload and unload the packages. The transport control device 10 receives the transport request at the transmission / reception unit 11, the control unit 12 specifies the transport priority based on the transport priority table, and stores the transport request stored in the storage unit 13. Add to the list (see FIG. 4). Next, when there is a transfer instruction request from any of the automatic guided vehicles A1 to A3, the control unit 12 of the transfer control device 10 specifies the device and port of the nearest stacking point from the nearest stacking point table (see FIG. 2). Then, all transfer requests that can be assigned from the stored transfer request list (see FIG. 4) are registered in the transfer instruction candidate list (see FIG. 5) of the storage unit 13 as transfer instructions. Next, after confirming the operation state of the buffer stations B1 and B2, the transfer instruction having the highest priority from the transfer instruction candidate list is assigned to the unmanned transport vehicle that has requested the transfer instruction. The wholesaler is buffer station B1,
In B2, if one of the buffer stations has no empty shelves or is out of order, the apparatus at the wholesale point is changed and a transfer instruction is allocated.

Although not described in detail here, the transfer control device 10 checks not only the buffer stations B1 and B2 but also the operation status such as failure of the automatic guided vehicles A1 to A3 and the production devices E1 to E4, You can also assign instructions. The transfer request is sent to buffer station B.
1, B2 and the production devices E1 to E4, but may be transmitted from another transport request device, or may be input by an operator using an input device.

Next, a method of adding to the transport request list will be described. For example, it is assumed that a transport request in which the ports P5 and P6 of the production device E2 are loading points and the port P4 of the buffer station B1 is a wholesale point is transmitted to the transport control device 10. Hereinafter, each transport request is E2 / P5
→ B1 / P4, E2 / P6 → B1 / P4. The transfer control device 10 determines a transfer priority based on the information of the transfer point and the wholesale point of the transfer request and the transfer priority table (see FIG. 3) defined in advance and stores the transfer priority in the transfer request list. to add. Therefore, the transfer request list stores the loading point, the wholesale point, the transfer priority, and the change time as a list, and the transfer priority changes after the change time elapses. However, the smaller the transport priority here, the higher the priority level.

The priority initial value in the transport priority table (FIG. 3) is a priority added by the transport control device when a transport instruction relating to the device is transmitted, and the change time is one priority. The cycle time (minutes) to be given. The priority initial value and the change time are numerical values determined based on the takt time of the production devices E1 to E4 and the amount of work in progress to the devices, and may be determined in advance by a person or by a certain calculation formula. You may make it calculate automatically. When the priority initial value and the change time are different between the loading point and the wholesale point, the smaller value is adopted for the priority initial value, and the smaller value is also used for the change time.

From the transport priority table shown in FIG. 3, E2 / P5
→ In the case of the Bl / P4 transfer instruction, the priority initial value and the change time of the port P5 of the device E2 at the loading point are 8, 6 respectively, and the priority initial value of the port P4 of the device B1 at the wholesale point,
Since the change times are 10 and 9, respectively, the priority initial value of this transport request is determined to be 8 and the change time is determined to be 6. In this way, the transport control device assigns a priority of 8 to the transport request of E2 / P5 → B1 / P4 and adds the priority to the transport request list, and decreases the priority value by one every six minutes. Similarly, the priority initial value and the change time of the port P6 of the device E2 at the loading point are 10 and 6, respectively, and the port P of the device B1 at the wholesale point is
Because the priority initial value and the change time of priority 4 are 10 and 9, respectively, the priority is added to the transport request list with the priority 10 added to the transport request of E2 / P6 → Bl / P4, and the priority is changed every 6 minutes. The value of is reduced one by one. When it is necessary to raise the priority of a specific transport request, the transport controller 10
It may be possible to manually raise the priority to an arbitrary priority from a transport terminal (not shown) connected to the terminal. In this way, every time a transfer request is transmitted, the transfer control device 10 adds the transfer request to the transfer request list stored in the storage unit 13. When the transfer control device 10 receives transfer instruction requests from the automatic guided vehicles A1 to A3, all transfer requests that can be assigned are registered as transfer instructions in the transfer instruction candidate list of the storage unit 13, and the highest priority is assigned. Allocate high transport instructions to automatic guided vehicles.

Next, a method of allocating the transfer instruction in the transfer request list to the automatic guided vehicle will be described. Here, FIG. 6 is a flowchart for explaining a method of instructing conveyance to the automatic guided vehicle.

First, when the automatic guided vehicle A2 having no transport instruction passes the transport inquiry point T3 (step S1), the automatic guided vehicle A2 having no transport instruction issues a transport instruction request (step S2). In response to the transfer instruction request from the transfer inquiry point T3, a transfer request using the port of the device defined in the nearest stacking point table (see FIG. 2) from the transfer request list (see FIG. 4) as a stacking point. Check whether or not exists (step S
3). The nearest loading point table indicates that when there is a transport instruction request from the automatic guided vehicle, the loading points in the transport request list are
It is used to determine whether or not the vehicle is within a certain section from the transportation inquiry point T3 where the transportation instruction request was issued.

When the automatic guided vehicle A2 issues a transfer instruction request at the transfer inquiry point T3 during traveling, from the nearest stack point table of FIG. 2, the transfer control device 10 determines that the nearest stack point of the transfer inquiry point T3 is the device E2. Port P5 or P6. Next, it is checked whether or not a transfer instruction having the port P5 or P6 of the apparatus E2 as a stack point exists in the transfer request list. if,
If there is no transfer instruction satisfying the condition in the transfer request list, an instruction to continue the work is given to the automatic guided vehicle A2 (step S4). Therefore, the automatic guided vehicle A2 requests a transfer instruction again when passing the next transfer inquiry point T2 (step Sl).

If there are transfer instructions satisfying step S3, all the transfer instructions are registered in a transfer instruction candidate list (see FIG. 5) (step S5). The transfer instruction candidate to be assigned to the unmanned transfer A2 requested to be transferred at the transfer inquiry point T3 is E2 / P5, which is the aforementioned transfer request.
Bl / P4 (conveyance priority 8), E2 / P6 → Bl / P4
(Transport priority 10). Then, the transport instruction having the highest priority among the transport instruction candidates (E2 / P5 → Bl / P)
4) is selected (step S6), and it is checked whether the wholesaler of the transfer instruction is the buffer station B1 or B2 (step S7).

If the wholesaler is a buffer station B1,
If it is not B2, the transfer request is deleted from the transfer request list (step S8), and a transfer operation is instructed to the automatic guided vehicle A2 (step S9). When the wholesaler apparatus is the buffer station Bl, it is checked whether there is an empty shelf in the buffer station Bl) (step SlO) or whether it is out of order (step Sll). If there is no empty shelf in the buffer station Bl and there is no failure, the transfer instruction is deleted from the transfer request list (step S8), and a transfer operation is instructed to the automatic guided vehicle (step S9).

If there is no empty shelf in the buffer station B1 or if there is a failure, it is checked whether there is another buffer station that can be transferred and transferred (step S12). If there is a transferable buffer station, the transferable buffer station B2 is selected (step S13), and the selected buffer station B2 is similarly checked whether there is an empty shelf or not in failure (step S13). Step Sl
O, Sll). If there is no other buffer station to be transferred, the transfer instruction is deleted from the transfer instruction candidate list (step S14), and after the deletion, it is checked whether there is a transfer instruction in the transfer instruction candidate list (step S15).

If the transfer instruction still remains in the transfer instruction candidate list, the transfer instruction with the highest priority is selected again from the transfer instruction candidate list (step S6). If there is no transfer instruction in the transfer instruction candidate list, an instruction to continue work is given to the automatic guided vehicle (step S4). In this case, the unmanned transport vehicle requests the transport instruction again when passing through the next transport inquiry point. The unmanned guided vehicle to which the transfer instruction is assigned performs the loading operation at the loading point (step S16), and travels toward the wholesale point (step S16).
17), a wholesale operation is performed at the wholesale point (step S1)
8). Then, after the wholesale operation, a transfer instruction request is made at a wholesale point to obtain a new transfer instruction (step S2).

[0029]

According to the first aspect of the present invention, a transfer instruction for designating a loading apparatus and a wholesale apparatus to be transferred is allocated to the automatic guided vehicle that has issued a transfer instruction request from the transfer inquiry point. Therefore, an instruction is issued to an unmanned transport vehicle that does not have a transport instruction, so that the vehicle can reach the loading side device quickly, and efficient transport control can be realized.

According to the second aspect of the present invention, since the transfer instruction is performed starting from the stacking side device within a certain section close to the transfer inquiry point, the automatic guided vehicle that issues the transfer instruction request can promptly send the stacking side device to the stacking side device. And efficient transport control can be realized.

According to the third aspect of the present invention, among the transfer instructions, the transfer instruction having the highest priority level is assigned to the automatic guided vehicle according to the transfer priority, so that the loading and unloading of the loading and unloading apparatuses is performed. Waiting time can be reduced.

According to the fourth aspect of the present invention, since the initial value of the transfer priority is determined based on the tact time, the amount of work in progress, and the like of the loading side device and the unloading side device, It is possible to greatly reduce the time lost in waiting for loading and unloading of the wholesale apparatus.

According to the fifth aspect of the present invention, the automatic guided vehicle, the loading side device and the unloading side device have a function of confirming whether or not the operation is possible. Therefore, efficient transport control can be realized without delaying the transport of the load.

[Brief description of the drawings]

FIG. 1 is an overall view showing an automatic guided vehicle transport control system according to the present invention.

FIG. 2 is an explanatory diagram showing a nearest stacking point table.

FIG. 3 is an explanatory diagram showing a transport priority table.

FIG. 4 is an explanatory diagram showing a transport request list.

FIG. 5 is an explanatory diagram showing a transfer instruction candidate list.

FIG. 6 is a flowchart for explaining a method of instructing conveyance to an automatic guided vehicle.

FIG. 7 is an overall view showing an example of a conventional automatic guided vehicle control system.

[Explanation of symbols]

 10 Transport control device A1 to A3 Automatic guided vehicle B1, B2 Buffer station E1 to E4 Production device R1 to R3 Travel route T1 to T6 Transport inquiry point

──────────────────────────────────────────────────続 き Continuing from the front page (72) Inventor Shunji Mizutani 3-11-1, Shimosakabe, Amagasaki-shi, Hyogo Nippon Machinery Co., Ltd. (56) References JP-A-5-197424 (JP, A) JP-A-5-197425 (JP, A) JP-A-5-127744 (JP, A) JP-A-10-268937 (JP, A) JP-A-8-225107 (JP, A) JP-A-8-26412 (JP JP, A) JP-A-7-95146 (JP, A) JP-A-7-44234 (JP, A) (58) Fields investigated (Int. Cl. ⁷ , DB name) G05D 1/02

Claims (5)

(57) [Claims] 1. A plurality of automatic guided vehicles for automatically transporting a package to a destination according to a transport instruction, a traveling route on which the automatic guided vehicle can travel and overtake, and loading and unloading of the package transported by the automatic guided vehicle. A loading side device and a wholesale side device, which are provided on the traveling route, and at least one or more transport inquiry points at which an unmanned guided vehicle having no transport instruction issues a transport instruction request, based on the transport instruction request, A transfer control device that controls the traveling of the automatic guided vehicle, and the transfer control device, for the automatic guided vehicle that has issued a transfer instruction request from the transfer inquiry point, a loading device and a wholesaler to be transferred. An automatic guided vehicle control system characterized by assigning a transfer instruction for designating a device. 2. The automatic guided vehicle control system according to claim 1, wherein the transfer control device issues a transfer instruction starting from a loading side device in a fixed section close to the transfer inquiry point. 3. The transfer control device according to claim 1, wherein the transfer control device stores necessary transfer instructions, and assigns a transfer instruction having a highest priority level to the automatic guided vehicle from the transfer instructions according to a transfer priority. The automatic guided vehicle control system according to claim 1 or 2, wherein: 4. The transfer priority, wherein an initial value of the transfer priority is determined based on a tact time and a work-in-progress amount of the loading apparatus and the unloading apparatus, and is changed with the lapse of time after the issuance of the transfer instruction. The automatic guided vehicle control system according to claim 3, wherein: 5. The transfer control device according to claim 1, wherein the automatic transfer vehicle includes:
The automatic guided vehicle control system according to any one of claims 1 to 4, further comprising a function of confirming whether or not the loading side device and the unloading side device can be operated, and changing to another transportation instruction when the operation cannot be performed. .