JPH11110041A - Automated guided vehicle - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent a vehicle from getting ahead of or passing another vehicle at a specified place on a travel path. SOLUTION: When a vehicle A enters an attention area, the vehicle A sends information (entry information) on the current position of the vehicle to a vehicle B, which once receiving the entry information, sends information (response information) on its current position and travel direction. The vehicle A when receiving the response information judges the approach between the vehicles A and B from the said two pieces of information (entry information and response information); when the opposition distance decreases below a specific value, the vehicle A is commanded to stop and the number of approaching vehicles B is set in a counter. When information on leaving the attention area is received from the vehicle B, the counter is counted down by one and when the counter reaches 0, the resetting of the stopping of the vehicle A is commanded.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention travels along a guide band laid on a floor surface, inputs parts and materials to an arbitrary process (also called a cell), and converts a completed product or a semi-finished product to another process. The present invention relates to an unmanned transport vehicle that shifts to a process, and more particularly to an unmanned transport vehicle that enables easy passing and passing.

[0002]

2. Description of the Related Art An AGV (Automatic Guided Vehicle) runs along a guide band such as a magnetic guide laid on the floor.
Unmanned transport vehicles, which are referred to as e), are indispensable equipment for labor saving and automation in factories. Since the operation route can be freely changed just by rebuilding the guide belt, it is possible to flexibly respond to process changes and the like. Although it is advantageous in terms of point, there is a drawback that, when a plurality of units are operated at the same time, traffic congestion cannot be denied, and the productivity of the factory cannot be increased.

[0003] The inventors of the present invention have previously proposed a technique that allows vehicles to easily pass each other (Japanese Patent Application No. 8-223476, August 26, 1996).
This technology, by exchanging information such as travel position and priority between the unmanned transport vehicles, grasps the positional relationship between the own vehicle and other vehicles in each vehicle, if any traffic congestion, One or both of the vehicles autonomously change the running path and make an easy pass.

[0004]

However, in such an unmanned transport vehicle of the prior application, when there is traffic congestion, it is easy to overtake regardless of the location. However, there is an inconvenience that the change of the traveling road causes the vehicle to hit an obstacle or to come into contact with another vehicle that enters or exits the cell, thereby increasing traffic congestion.

SUMMARY OF THE INVENTION It is an object of the present invention to prevent a driver from passing or passing another vehicle at a designated location on a track.

[0006]

According to the first aspect of the present invention,
(A) position detecting means for detecting a traveling position; (b) direction detecting means for detecting a traveling direction; and (c) entering and leaving an attention area arbitrarily set on a track. Area detecting means for detecting; (d) first transmitting means for transmitting, when the area detecting means detects intrusion into the caution area, intrusion information including information on a traveling position at that time; (e) Receiving means for receiving information from another vehicle; and (f) second transmitting means for transmitting response information including information on a traveling position and a traveling direction at the time of receiving intrusion information from another vehicle; (G) When response information from another vehicle is received immediately after transmitting the intrusion information by the first transmission means, the distance to another vehicle approaching the own vehicle based on the intrusion information and the response information. Is calculated, and if the distance falls below a predetermined value, Sets the number of all approaching vehicles in a counter, and instructs the first vehicle to stop traveling of the own vehicle; and (h) that the area detection unit detects that the vehicle has left the caution area. At this time, a third transmitting means for transmitting withdrawal information indicating the withdrawal,
(I) When the own vehicle is in the traveling stop state, the value of the counter is decreased by one every time when the departure information from another vehicle is received, and when the value of the counter becomes 0, the stop of the own vehicle is released. And second command means for commanding.

According to the first aspect of the present invention, when a certain vehicle (referred to as vehicle A) enters the caution area, information on the current position of vehicle A (referred to as intrusion) is transmitted from vehicle A to another vehicle (referred to as vehicle B). When the intrusion information is received by the vehicle B, information (response information) on the current position and the traveling direction of the vehicle B is transmitted from the vehicle B. When the response information is received by the vehicle A, the approach between the vehicles A and B is determined from the above two information (intrusion information and response information). A stop command is issued, and the number of vehicles B approaching is set in the counter. Thereafter, when information of leaving the caution area from the vehicle B is received, the counter is decremented by one, and when the value of the counter becomes 0, the stop release of the vehicle A is commanded.

[0008]

Embodiments of the present invention will be described below with reference to the drawings. 1 to 7 are views showing one embodiment of an unmanned transport vehicle according to the present invention. As described at the beginning, the unmanned transport vehicle of this embodiment travels along the guide band laid on the floor surface, inputs parts and materials to an arbitrary process (cell), and supplies finished products or semi-finished products. This is an improvement of an unmanned transport vehicle that enables finished products to be transferred to other processes, and also enables passing and passing. Therefore, it is needless to say that it has a basic function before the improvement, for example, a function of traveling along the guidance zone, a function of transferring a load, and a function of easily passing or passing, and in the following description, it is added in the present embodiment. The function will be described.

FIG. 1 is a functional conceptual diagram common to all automatic guided vehicles traveling along a guide zone. In the figure,
a is a position detecting means, b is a direction detecting means, c is an area detecting means, d is a first transmitting means, e is a receiving means, f is a second transmitting means, g is a first commanding means, and h is a first transmitting means. 3 transmission means,
i is second command means, 10 is a transmitting / receiving antenna, and 11 is a counter. The symbols a to i correspond to the identification codes assigned to the respective items of the invention described in claim 1.

The position detecting means a, the direction detecting means b and the area detecting means c respectively enter the current position and the traveling direction of the own vehicle and intrude into a specific area (referred to as a caution area) arbitrarily set on the track. The detecting means for detecting departure, the receiving means e for receiving information from another vehicle, the first to third means
The transmitting means d, f, and h respectively transmit predetermined information in response to a predetermined event, and the relationship between the event and the transmission information is as shown in Table 1 below. (Below)

[0011] Further, the first command means g and the second command means i are commands for stopping the running of the own vehicle and canceling the stop of the running under predetermined conditions, respectively. It is as shown in Table 2. (Below)

[0012] FIG. 2 is a diagram showing three unmanned transport vehicles traveling along the guidance zone 20, where 10 is a transmitting / receiving antenna, and 12 is each detecting means (position detecting means a, direction detecting means b, and area detecting means c). Is a wheel, and 13 is a wheel. In this example, the vehicle at the left end of the drawing (vehicle A) is traveling rightward, and the vehicle at the center (vehicle B) and the vehicle at the right end (vehicle C) are traveling leftward. That is, each vehicle is traveling in a direction in which the distance between the vehicle A and the vehicle B and the distance between the vehicle A and the vehicle C are approaching. In the figure, reference numerals 21 to 25 denote position markers, and these position markers 21 to 25 can use magnetic pole patterns coded by setting the N pole to logic 1 and the S pole to logic 0. For example, if the pattern array is [NSSNNN], [1
00111].

Here, when a position information field is composed of several bits and one of the remaining bits is used as a designated bit for the attention area, for example, the most significant bit is used as the area designating bit, and the remaining bits are used as the designated bits. In the case of the position information field, in [100111] in the above example, the area designation is [1] and the position information is [00111]. That is, if logic 1 is set to true, [1001
The position marker having the pattern of [11] has a position address of [7] in decimal notation and is a marker indicating a caution area.

In FIG. 2, two position indicators 22 and 23 indicated by hatching are markers in which the area designation bit is set to [1].
The area between 3 is the attention area 26. Note that the setting of the caution area (setting of the above-mentioned area designation bit) is arbitrarily set by the manager of the automatic guided vehicle, but in particular, it is not possible to secure a sufficient space around the guiding zone 20 due to the layout of the factory. It should be set at a location or near a cell entrance. This is because it is difficult to overtake or make a difference in these places.

FIGS. 3 and 4A are overhead views of FIG. The pointed portion of each of the vehicles A to C is a body front, and these drawings show a state in which the running vehicle A is located directly above the hatched position mark 22.
In other words, this indicates a state in which the vehicle A has entered the caution area 26, and the first vehicle shown in Table 1 above inside the vehicle A.
Event (intrusion into the attention area) has occurred. For this reason, the intrusion information (information on the traveling position of the vehicle A) is transmitted from the vehicle A from the above table 1, and the second event (reception of the intrusion information) shown in the above table 1 inside the other vehicles B and C. ), Response information (information on the traveling positions and traveling directions of the vehicles B and C) is transmitted from the other vehicles B and C, respectively.

Response information from the other vehicles B and C is received by the vehicle A, and the degree of threat of the vehicles B and C is evaluated. For example, if the traveling direction of the vehicle B or the vehicle C is a direction away from the vehicle A, the vehicle B or the vehicle C does not pose a threat to the vehicle A, or even if the approaching direction is the vehicle B or the vehicle C, If the distance is sufficiently large (see FIG. 5A), this does not pose a threat. In addition, the sufficient distance is
This is the distance at which the vehicle A does not encounter the vehicle B or the vehicle C while passing through the caution area 26.

When the vehicle B or the vehicle C is evaluated as a threat in the vehicle A, the vehicle A stops immediately and the number of the threat vehicles is counted by a counter 11 (see FIG. 1).
Set to. FIG. 5 is a traveling state diagram when the distance between the vehicles is sufficiently large (when the vehicle is not evaluated as a threat). The vehicle B and the vehicle C continue to travel,
When the vehicle A encounters the stopped vehicle A (FIG. 4B), an operation of avoiding the vehicle A (in this case, a passing operation of slightly changing the running path and passing the side of the vehicle A) is performed (FIG. 4). (C))
However, since this avoidance operation is performed at the stop position of the vehicle A, that is, at the end of the caution area 26, the leaving information of the attention area 26 is transmitted from the vehicle B or the vehicle C performing the avoidance operation.

The stopped vehicle A decreases the value of the counter 11 by one each time it receives the departure information.
When the departure information from the vehicle C is received, the value of the counter 11 is changed from [2] to [1], and when the departure information from the vehicle C is received, the value is decremented from [1].

Set to [0]. And the value of the counter 11 is

When it becomes [0], the vehicle A releases the stop of traveling and starts traveling.

As described above, in the present embodiment, when the vehicle A enters the caution area 26 arbitrarily set on the track, the threats of the other vehicles B and C are evaluated. A is stopped immediately, so that the vehicles do not meet each other inside the caution area 26. Therefore, it is possible to avoid passing or passing each other inside the caution area 26, and to prevent collision with an obstacle or contact with a vehicle,
An advantageous effect not obtained by the prior art that the smoothness of traffic can be ensured and the productivity of the factory can be improved.

In the above description, the caution area is set in a part of the guide zone, but the present invention is not limited to this. For example, since the entrance of the process (cell) is also a place where traffic congestion is likely to occur, the vicinity of the entrance may be set as the caution area.
In FIG. 6, reference numerals 30 and 31 are cells. In FIG. 6A, the vehicle A is in the cell 30 on the left side, and the other vehicle B
Are approaching near the entrances of the cells 30 and 31. Note that the cells 30 and 31 are also provided with the same position markers (particularly, the position markers 22 and 23 indicating the attention area) described above.

Now, the vehicle A moves away from the cell 30 and
Assuming that the operation of returning to zero has started, the start of this operation corresponds to the intrusion of the vehicle A into the caution area 26 in the above description (see FIG. 4A). This is the induction zone 20
This is because the information of the position indicator of the cell 30 is evaluated when the operation of returning upward is started. Accordingly, the vehicle A transmits the intrusion information, and the other vehicle B transmits response information corresponding to the intrusion information. Since the vehicle B poses a threat to the vehicle A, the vehicle A is instructed to stop traveling. . When the vehicle B leaves the caution area (passes through the second caution area sign 22 along the traveling direction), the vehicle B transmits the departure information (FIG. 6B), which is a threat in this case. Since there is only one vehicle, the suspension of the traveling of the vehicle A is released in response to the departure information, and the vehicle A resumes the operation of returning to the guidance zone 20 (FIG. 6C).

In the above description, the example in which the other vehicle B is traveling along the guidance zone 20 has been described. However, the present invention is not limited to this. For example, as shown in FIG. 7, the present invention can be applied to a case where another vehicle B enters an empty cell 31. The difference from the above example lies in the determination of the departure of the other vehicle B from the caution area.
In FIG. 7, if the vehicle B is turning at the time of passing the first caution area sign 23 along the traveling direction, it is determined that the vehicle B has left the caution area (transmission of the departure information).

[0023]

According to the present invention, it is possible to prevent passing at a designated place (caution area) on a runway and to avoid passing each other. Therefore, by setting an appropriate caution area, traffic congestion can be avoided and the productivity of the factory can be improved.

[Brief description of the drawings]

FIG. 1 is a functional conceptual diagram of one embodiment.

FIG. 2 is a traveling state diagram of three vehicles of one embodiment.

FIG. 3 is an overhead view of FIG. 2;

FIG. 4 is an explanatory diagram of a traveling state of the embodiment (when the vehicle A is stopped).

FIG. 5 is an explanatory diagram of a traveling state of the embodiment (when the vehicle A is not stopped).

FIG. 6 is an explanatory view of a traveling state according to one embodiment (case where a caution area is around an entrance / exit of a cell: No. 1).

FIG. 7 is an explanatory diagram of a traveling state according to one embodiment (case where a caution area is around an entrance / exit of a cell: part 2).

[Explanation of symbols]

 a: Position detecting means b: Direction detecting means c: Area detecting means d: First transmitting means e: Receiving means f: Second transmitting means g: First commanding means h: Third transmitting means i: First 2 command means

Claims (1)

[Claims] (A) position detecting means for detecting a traveling position; (b) direction detecting means for detecting a traveling direction;
(C) area detecting means for detecting intrusion into and leaving from the caution area arbitrarily set on the runway; and (d) when the intrusion into the caution area is detected by the area detecting means, First transmitting means for transmitting intrusion information including information on the traveling position at that time, (e) receiving means for receiving information from another vehicle, and (f) when receiving intrusion information from another vehicle, Second transmission means for transmitting response information including information on the traveling position and traveling direction at that time; and (g) receiving response information from another vehicle immediately after transmitting the intrusion information by the first transmission means. Calculating a distance to another vehicle approaching the own vehicle based on the intrusion information and the response information, and if the distance is smaller than a predetermined value, counts the number of all approaching vehicles to a counter. Set your own vehicle (H) third transmission means for transmitting, when the area detection means detects a departure from the caution area, departure information indicating the departure, and (i) When the own vehicle is in the running stop state, the value of the counter is reduced by one each time the departure information from the other vehicle is received, and when the value of the counter becomes 0, an instruction to release the running stop of the own vehicle is issued. Second
And an instructing means.