JPH10247112A - Mobile assignment method - Google Patents

Abstract

(57) [Summary] [PROBLEMS] To provide a moving object assignment method capable of efficiently assigning a moving object to a request from a request source. SOLUTION: A predetermined area is divided into a plurality of areas, a control center is arranged for each area, an allocation in the area is performed by a control center belonging to the area, and an allocation request from a request source is made. If there is no mobile unit that can be assigned in the area to which the mobile unit belongs, the control center that requests the mobile unit is determined based on the destination selection rate set in advance for each of the other control centers, and the determined control center is determined. , A mobile object request message is broadcast, a bidding message and a successful bid message are exchanged with the control center, and the mobile object is allocated.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a moving object allocating method for repeatedly allocating a plurality of moving objects such as an autonomous mobile robot and an automatic guided vehicle to a plurality of request sources.

[0002]

2. Description of the Related Art Hitherto, as a system to which a moving object allocation method for repeatedly allocating a moving object such as an autonomous mobile robot or an automatic guided vehicle to a request source has been applied, for example, there is a luggage transfer system in a factory or a distribution terminal. This is a system for allocating an appropriate automatic guided vehicle to a cargo transport request generated in a warehouse, a loading / unloading place or a building, and transporting the cargo.

[0003] In such a conventional system, one control center, a plurality of mobile units, and a plurality of request sources are constituted.
Each component has appropriate communication means so that messages can be exchanged with each other. And
Each moving body can autonomously move to the destination by indicating the destination. In addition, the control center can acquire the current positions of all the mobile units that can be assigned in the area, and can know the distance between any two points in the area based on the map data.

[0004] The assignment of a mobile unit to a requesting source includes:
The following method was used. First, a requester who wants to receive the assignment of a mobile unit issues an assignment request to the control center. When the control center receives the allocation request from the requesting source, the control center issues a movement instruction to the moving body located at the closest distance to the requesting source. Then, the moving body that has received the movement instruction from the control center moves to the request source specified by the movement instruction. In this way, the assignment of the mobile unit to the request source is completed.

[0005]

However, in the conventional mobile unit allocating method, the control center manages the positions of all the mobile units and selects the optimum one from all possible combinations of the mobile unit and the request source. Therefore, there is a problem that a large-scale system having a relatively large number of mobile units and request sources requires a large amount of processing and makes real-time control difficult.

[0006]

SUMMARY OF THE INVENTION A moving object allocating method according to the present invention includes a plurality of moving objects and a plurality of requesters for requesting the allocation of the moving objects in a predetermined area, and requests the allocation of the moving objects. In the mobile object assignment method of repeatedly assigning a plurality of mobile objects to a plurality of request sources, a predetermined area is divided into a plurality of areas, a control center is arranged for each area, and a request source existing in the area and The mobile unit is defined as a requestor and a mobile unit belonging to the area, and the requester who wishes to receive the allocation of the mobile unit issues an allocation request to a control center in the area to which the requestor belongs and receives the allocation request. If there is a mobile that can be allocated in the area to which it belongs, the control center selects the mobile that is closest to the requestor who issued the allocation request from the mobiles, and assigns it to the selected mobile. Against When a mobile unit is assigned by issuing a move instruction and there is no mobile unit that can be allocated in the area to which the mobile unit belongs, the mobile unit is assigned based on the destination selection rate set in advance for each of the other control centers. The control center to be requested is determined, a mobile unit request message is issued to the determined control center, and the control center that receives the mobile unit request message can move within the area to which the control center belongs. A bidding message to which the body position and the identifier are added is issued to the control center that issued the movement request message, and the control center that receives the bidding message from the control center transmits information on the mobile body added to the bidding message. The required number of mobile units close to the request source that issued the allocation request are selected in order based on the Is issued to the control center to which the selected mobile unit belongs, and the control center receiving the successful bid message sends the successful bid message with the identifier added to the successful bid message to the control center to which the selected mobile unit belongs. Is issued to the request source that has issued the allocation request to the mobile station, and the mobile unit is allocated.

[0007]

BEST MODE FOR CARRYING OUT THE INVENTION

Embodiment 1 FIG. FIG. 2 is an explanatory diagram for explaining a mobile object allocation method according to the present invention, and shows a configuration example of a mobile object allocation system to which the mobile object allocation method according to this embodiment is applied.

As shown in FIG. 2, in this mobile unit assignment system, the moving area of the mobile unit is virtually divided into a plurality of sections, and one control center is arranged in each section. . Also, in the moving area of the moving object, there are a plurality of moving objects and a plurality of requesting sources, and each moving object and each requesting source belong to the area when they are in the area. State. The control center, the mobile unit, and the requesting source have appropriate communication means, and can exchange messages with each other.

[0009] Further, the mobile body can autonomously move to the destination by indicating the destination, and each control center can move to a mobile station belonging to the area of the control center. You can get your body position. Then, the position of the moving object may be continuously obtained by each control center, or may be obtained at predetermined time intervals. In addition, each request source can acquire the area to which it belongs, such as by acquiring its own position.

There is no particular limitation on how to divide the area in the moving area of the moving object. For example, in a factory including a plurality of buildings, one building may be regarded as one area,
In the case of a skyscraper, several consecutive floors may be considered as one area.

Next, the operation of this embodiment will be described. FIG. 1 is an explanatory diagram for explaining the operation of this embodiment. In FIG. 1, (a) of FIG. 1 shows an operation when there is a mobile unit that can be assigned in a requester's belonging area, and (b) of FIG. The operation when there is no body is shown.

First, each mobile unit transmits information on its own position, whether it is movable, and the like to a control center in the area to which the mobile unit belongs.
It is assumed that the control center has grasped the state of the moving object belonging to the area to which the control center belongs (11, 21). And
The requester who wants to receive the assignment of the mobile unit issues an assignment request to the control center in the area to which the requester belongs (1).
2, 22).

The control center that has received the allocation request, if there is a mobile that can be allocated in its area,
Then, a move instruction is issued to the requesting source from the moving object located at the closest distance (13), and the moving object receiving the move instruction moves to the designated requesting source and the assignment is completed (14).

If there is no mobile unit that can be allocated in the area to which the control center that has received the allocation request belongs, the following message exchange is performed between the control centers to move the mobile unit from another area. To assign. First,
The control center receiving the assignment request adds a destination of the control center stochastically determined according to the destination selection rate of the control center as a destination of the mobile request message, and sends the destination to the control center of the destination. Issue a mobile request message (23).

The destination selection rate is composed of a set of numbers corresponding to the number of other control centers such that the sum is 1. The value of the destination selection rate is heuristically determined by the system designer in advance in accordance with the form of the system. If there is a simulator that can simulate the mobile object allocation system, some candidates become candidates. Evaluate in combination, minimize waiting time, etc.
What is necessary is just to employ | adopt the group which optimizes the objective function of a system more.

For example, ten control centers (A ₀ ,
A _1, ..., a system consisting of A _9), control center A ₀
From, it is assumed that the distance is short in the order of A ₁ , A ₂ , ..., A ₉ . At this time, if the designer decides to issue the mobile object request message to the upper four control centers having a short distance with equal probability, the destination selection rate becomes as follows. (0.25,0.25,0.25,0.25,0,0,0,0,0)

In the case of such a destination selection rate, when one moving body is required, the control centers A ₁ , A ₂ , A
_3, since A ₄ destination selectivity is the same for one control center of the control center A _1, A _2, A _3, A ₄ is selected as the destination with equal probability, the mobile requests for the control center Will issue a message.

If a plurality of mobile units are required at the same time, a control center to which the mobile unit is requested is determined one by one for each of the plurality of mobile units according to the destination selection rate. As a result, if a plurality of requests are issued to one control center, the number of requests is added to a mobile object request message to the control center.

The other control center receiving the mobile request message from the control center issues a bid message to the control center that has issued the mobile request message (24). An identifier and a position of a movable mobile unit existing in the area to which the control center that has received the mobile unit request message is added to the bid message. At this time, if a certain control center has received a mobile request message from a plurality of control centers, the mobile units are distributed to the ratio of the number of requests added to each mobile request message, and a bid message is sent. Issue

The control center that has received the bid message selects the required number of mobile units in order from the one closest to the request source based on the information on the mobile unit added to the bid message. Then, a successful bid message is issued to the control center to which the selected mobile unit belongs (2.
5). The identifier of the selected mobile unit and the position of the request source are added to this successful bid message.

The control center that has received the successful bid message issues a move instruction to the request source for the mobile body with the identifier added to the successful bid message (26). It moves to the request source which issued the assignment request, and the assignment is completed (27).

Here, if the number of movable objects added to the bid message from each control center is smaller than the number of mobile objects added to the mobile object request message, Issue the request message again.

In this embodiment, the moving area of the moving body is divided into a plurality of areas, and a control center is arranged in each area.
Allocation within an area is performed by the control center belonging to that area, so allocation can be performed at high speed even when the scale is large or the number of mobiles is large, and the number and demand of mobiles between areas can be increased. Even if the frequency of occurrence is uneven, the mobile unit can be moved by exchanging messages between control centers, so that efficient allocation can be performed.

Embodiment 2 FIG. This embodiment is different from the first embodiment in that, when there is no mobile unit that can be assigned in the area to which the requester belongs, the control center that has issued the successful bid message sends a request to the mobile unit specified in the successful bid message. , An instruction to move to the area to which the requester belongs is issued, and after arriving at the area to which the requester belongs, an instruction to move to the requester from the control center belonging to that area is issued. The configuration of a mobile object assignment system to which the mobile object assignment method of this embodiment is applied is the same as that of the first embodiment as shown in FIG.

Further, the control center, the moving body and the request source are as follows:
It has suitable communication means so that messages can be exchanged with each other. In addition, the mobile unit can autonomously move to the destination by indicating the destination, and each control center can determine the position of the mobile unit belonging to the area of the control center. Can be acquired. And the position of this mobile is
It may be obtained continuously and continuously by each control center, or may be obtained at predetermined time intervals. In addition, each request source can acquire the area to which it belongs, such as by acquiring its own position.

Next, the operation of this embodiment will be described. FIG. 3 is an explanatory diagram for explaining the operation of this embodiment. In FIG. 3, (a) of FIG. 3 shows the operation when there is a mobile that can be assigned in the area to which the requester belongs, and (b) of FIG. 3 shows the movement that can be allocated in the area to which the requester belongs. The operation when there is no body is shown.

First, each mobile unit transmits information on its own position and whether it is movable to a control center in the area to which the mobile unit belongs.
It is assumed that the control center has grasped the state of the mobile unit belonging to the area to which the control center belongs (31, 41). And
The requester who wants to receive the assignment of the mobile unit issues an assignment request to the control center in the area to which the requester belongs (3.
2, 42).

The control center that has received the allocation request, if there is a mobile that can be allocated in its area,
Then, a move instruction is issued to the mobile unit that is located at the closest distance to the request source (33), and the mobile unit that has received the move instruction moves to the specified request source, and the assignment is completed (34).

If there is no mobile that can be assigned in the area to which the control center that has received the assignment request belongs, the following message exchange is performed between the control centers, and the mobile is moved from another area. To assign. First,
The control center receiving the assignment request adds a destination of the control center stochastically determined according to the destination selection rate of the control center as a destination of the mobile request message, and sends the destination to the control center of the destination. Issue a mobile unit request message (43).

The destination selection rate is composed of a set of numbers corresponding to the number of the other control centers such that the sum is 1. The value of the destination selection rate is heuristically determined by the system designer in advance in accordance with the form of the system. If there is a simulator that can simulate the mobile object allocation system, some candidates become candidates. Evaluation may be performed in combination, and a set that further optimizes the objective function of the system, such as minimizing the waiting time, may be adopted.

For example, ten control centers (A ₀ ,
A _1, ..., a system consisting of A _9), control center A ₀
From, it is assumed that the distance is short in the order of A ₁ , A ₂ , ..., A ₉ . At this time, if the designer decides to issue the mobile object request message to the upper four control centers having a short distance with equal probability, the destination selection rate becomes as follows. (0.25,0.25,0.25,0.25,0,0,0,0,0)

In the case of such a destination selection rate, when one moving body is required, the control centers A ₁ , A ₂ , A
_3, since A ₄ destination selectivity is the same for one control center of the control center A _1, A _2, A _3, A ₄ is selected as the destination with equal probability, the mobile requests for the control center Will issue a message.

If a plurality of mobile units are required at the same time, the control center to which the mobile unit is requested is determined one by one for each of the plurality of mobile units according to the destination selection rate. As a result, if a plurality of requests are issued to one control center, the number of requests is added to a mobile object request message to the control center.

The other control center that has received the mobile object request message from the control center issues a bid message to the control center that issued the mobile object request message (44). An identifier and a position of a movable mobile unit existing in the area to which the control center that has received the mobile unit request message is added to the bid message. At this time, if a certain control center has received a mobile request message from a plurality of control centers, the mobile units are distributed to the ratio of the number of requests added to each mobile request message, and a bid message is sent. Issue

The control center that has received the bid message selects the required number of mobile units in order from the one closest to the request source based on the information on the mobile unit added to the bid message. Then, a successful bid message is issued to the control center to which the selected mobile unit belongs (4.
5). The identifier of the selected mobile unit and the position of the request source are added to this successful bid message.

The control center that has received the successful bid message issues an instruction to move to the area to which the control center that issued the successful bid message belongs to the mobile unit having the identifier added to the successful bid message (46). And
When the moving body that has received the movement instruction moves to the designated area (47), it issues an arrival report message to the control center belonging to that area (48). This arrival report message may be issued not only at the time of arrival at the designated area but also immediately before arrival.

The control center that has received the arrival report message instructs the mobile to move to the request source that has issued the allocation request earliest among the request sources that have issued the allocation request. (49), the moving body that has received the movement instruction moves to the request source, and the assignment is completed (50). Here, if the number of movable objects added to the bid message is smaller than the number of mobile objects added to the mobile object request message, the mobile object request message is issued again.

In this embodiment, the moving area of the moving body is divided into a plurality of areas, and a control center is arranged in each area.
Allocation within an area is performed by the control center belonging to that area, so allocation can be performed at high speed even when the scale is large or the number of mobiles is large, and the number and demand of mobiles between areas can be increased. Even if the frequency of occurrence is uneven, the mobile unit can be moved by exchanging messages between the control centers, so that efficient allocation can be performed. Instead of deciding, upon arrival in the area where the requester belongs,
Since the mobile unit that arrives early is assigned to the request source that issued the assignment request earlier, it is possible to balance the waiting time.

[0039]

As described above, according to the present invention, a predetermined area is divided into a plurality of areas, a control center is arranged for each area, and an assignment in the area is assigned to the control center belonging to the area. If there is no mobile unit that can be allocated in the area to which it belongs in response to the allocation request from the request source, the mobile unit is requested based on the destination selection rate set in advance for each of the other control centers. Control center to be
A mobile unit request message is issued to the determined control center, a bidding message and a successful bid message are exchanged with the control center, and a mobile unit is allocated. Even if the number of mobile units is large, allocation can be realized at high speed, and even if the number of mobile units and the frequency of request generation are uneven between areas, message exchange between control centers
Since the moving object can be moved, there is an effect that efficient assignment can be performed.

[Brief description of the drawings]

FIG. 1 is an explanatory diagram for explaining an operation of a first embodiment.

FIG. 2 is an explanatory diagram for explaining a mobile object assignment method according to the present invention.

FIG. 3 is an explanatory diagram for explaining an operation according to a second embodiment;

Claims (2)

[Claims] 1. A plurality of mobile units and a plurality of request sources requesting allocation of the mobile units are present in a predetermined area, and the plurality of mobile units are requested for the plurality of request sources requesting the allocation of the mobile units. In the mobile object allocation method, the predetermined area is divided into a plurality of areas, a control center is arranged for each area, and a request source and a mobile body existing in the area are requested to belong to the area. The requester who wants to receive the assignment of the mobile unit issues an assignment request to the control center of the area to which the requester belongs, and the control center that has received the assignment request assigns the area to which the requestor belongs. If there is a mobile that can be allocated within, select a mobile that is closest to the requester that issued the allocation request from among the mobiles, and issue a move instruction for the selected mobile, Transfer If a mobile body is allocated and there is no mobile body that can be allocated in the area to which it belongs, the control center that requests the mobile body is determined based on the destination selection rate set in advance for each of the other control centers, A mobile object request message is issued to the determined control center, and the control center receiving the mobile object request message adds the position and identifier of the movable object within the area to which the control center belongs. A bidding message is issued to the control center that has issued the movement request message, and the control center that has received the bidding message from the control center performs the assignment based on the information of the moving object added to the bidding message. The required number of mobile units close to the request source that issued the request are selected in order, and the identifier of the mobile unit and the assignment request are issued. The control center to which the selected mobile unit belongs is issued a successful bid message with the requester's location added, and the control center that receives the successful bid message sends a message to the mobile unit with the identifier added to the successful bid message. hand,
A mobile object allocation method, wherein a mobile device is allocated by issuing a transfer instruction to a request source that has issued the allocation request. 2. A method according to claim 1, wherein a plurality of mobile units and a plurality of request sources requesting the allocation of the mobile units are present in a predetermined area, and the plurality of mobile units are requested for the plurality of request sources requesting the allocation of the mobile units. In the mobile object allocation method, the predetermined area is divided into a plurality of areas, a control center is arranged for each area, and a request source and a mobile body existing in the area are requested to belong to the area. The requester who wants to receive the assignment of the mobile unit issues an assignment request to the control center of the area to which the requester belongs, and the control center that has received the assignment request assigns the If there is a mobile unit that can be allocated, select a mobile unit that is closest to the requester that issued the allocation request from among the mobile units, and issue a move instruction for the selected mobile unit, Transfer If a mobile body is allocated and there is no mobile body that can be allocated in the area to which it belongs, the control center that requests the mobile body is determined based on the destination selection rate set in advance for each of the other control centers, A mobile object request message is issued to the determined control center, and the control center receiving the mobile object request message adds the position and identifier of the movable object within the area to which the control center belongs. A bidding message is issued to the control center that has issued the movement request message, and the control center that has received the bidding message from the control center performs the assignment based on the information of the moving object added to the bidding message. The required number of mobile units close to the request source that issued the request are selected in order, and the identifier of the mobile unit and the assignment request are issued. The control center to which the selected mobile unit belongs is issued a successful bid message with the requester's location added, and the control center that receives the successful bid message sends a message to the mobile unit with the identifier added to the successful bid message. hand,
A mobile unit that issues a move instruction to the area to which the requester who has issued the allocation request belongs, and receives the move instruction, moves to the area instructed by the move instruction, and issues a command to the control center belonging to that area. The control center issues an arrival report message and receives the arrival report message.
The mobile station that has issued the arrival report message is issued a transfer instruction to the request source that issued the allocation request earliest in the area to which the control center belongs, and the mobile station is allocated. Mobile unit allocation method.