JP4442611B2 - Traveling vehicle system - Google Patents

Description

  The present invention relates to a deceleration control technique for mitigating vibrations in a traveling vehicle system having a plurality of traveling vehicles traveling along a predetermined traveling route and a host controller that controls traveling of the traveling vehicles.

  In recent years, factories that are production sites are being automated and unmanned. In such a background, various types of traveling vehicles are used in factories that are production sites. For example, an overhead traveling vehicle that travels along a traveling rail provided in a ceiling space, or an unmanned traveling vehicle that travels along a track provided on a floor surface or a trackless surface is known. These traveling vehicles have a role of conveying articles in the factory.

  In a route along which a traveling vehicle in the factory travels, there may be a rail step or unevenness due to a floor having changed state. When the traveling vehicle travels on these uneven portions at a normal speed, vibration is generated. Vibration during traveling is a cause of failure of equipment mounted on the traveling vehicle itself, and can also cause damage or collapse of the conveyed goods.

Conventionally, several techniques for countermeasures against vibration when traveling on uneven parts of a traveling vehicle are known.
For example, Patent Document 1 discloses an automatic guided vehicle having an anti-vibration damper between a traveling carriage and an automatic guided vehicle main body.
JP 2001-298065 A

Conventional vibration countermeasure techniques represented by these documents are limited to countermeasures for a single traveling vehicle.
However, in reality, many traveling vehicles are operating in the factory. In a factory where a large number of traveling vehicles are operating, the vibration countermeasures for a single traveling vehicle reduce the operating rate of the traveling vehicle system and are inefficient as vibration countermeasures.
Therefore, the problem to be solved is to take measures against vibration during traveling in the traveling vehicle system in which a plurality of traveling vehicles perform traveling control.

  The problem to be solved by the present invention is as described above. Next, means for solving the problem will be described.

That is, in claim 1, in a traveling vehicle system having a plurality of traveling vehicles traveling on a predetermined traveling route, the traveling vehicle detects vibration detection means for detecting a vibration value and a current traveling position. A traveling position detection unit, a communication unit that communicates a traveling position at which a vibration value equal to or greater than a predetermined value is detected by the vibration detection unit and the traveling position detection unit to a succeeding traveling vehicle, and a predetermined value by the communication unit of a preceding traveling vehicle. When a travel position at which a vibration value equal to or greater than the value is detected is communicated, it is assumed from the first deceleration means for reducing the travel speed when traveling at the position and the vibration value detected by the vibration detection means of the preceding traveling vehicle. Vibration value comparing means for comparing the vibration value to be measured .

  According to a second aspect of the present invention, in the traveling vehicle system according to the first aspect, the traveling vehicle decelerates the traveling speed of the own vehicle when a vibration value greater than or equal to a predetermined value is detected by the vibration detecting means of the own vehicle. A second reduction means is provided.

  According to a third aspect of the present invention, in the traveling vehicle system according to the first or second aspect, the vibration level detected by the vibration detecting means is divided into a plurality of levels, and a deceleration level calculation for decelerating the traveling speed according to the vibration value level. Means, and the first or second deceleration means decelerates according to the deceleration level calculated by the deceleration level calculation means.

  As effects of the present invention, the following effects can be obtained.

According to the first aspect of the present invention, when there is an uneven portion on the travel route, the traveling vehicle is informed of the position from the preceding vehicle, and can therefore travel at a reduced speed so as to reduce vibration during traveling. That is, vibration measures can be efficiently taken in the traveling vehicle system.
Moreover, since the uneven | corrugated location in a factory can be detected at an early stage, the said location can be repaired immediately.
Furthermore, even when there is a sudden situation such as damage to the rail, for example, if one traveling vehicle passes, the abnormality can be confirmed, so that it is possible to prevent the damage caused by vibration in the traveling vehicle system.
In addition, since the abnormality of the vibration detecting means can be detected immediately, a maintenance instruction or the like can be used to minimize a decrease in the operating rate of the traveling vehicle system.

  In the second aspect, in addition to the effect of the first aspect, the traveling vehicle itself that has detected the vibration can also travel at a reduced speed, so that the vibration can be further reduced.

  According to the third aspect, in addition to the effect of the first or second aspect, the deceleration control according to the vibration level is performed, so that a reduction in the operating rate of the traveling vehicle system can be minimized.

Next, embodiments of the invention will be described.
FIG. 1 is a block diagram showing the overall configuration of an automatic guided vehicle system according to the present embodiment, FIG. 2 is a block diagram showing the configuration of communication means of the automatic guided vehicle system, and FIG. 3 is a perspective view showing the automatic guided vehicle. It is.
4 is a block diagram showing the automatic guided vehicle controller, FIG. 5 is a graph showing the vibration level detected by the vibration detector, and FIG. 6 is a table showing the correlation between the vibration level and the deceleration level.
FIG. 7 is a flowchart showing the flow of predetermined deceleration control of this embodiment, FIG. 8 is a flowchart showing the flow of adaptive level deceleration control, and FIG. 9 is a flowchart showing the flow of vibration value comparison control.

  The traveling vehicle system of the present invention is applied to, for example, the automatic guided vehicle system 1. However, the present invention can be applied to any system in which a plurality of traveling vehicles travel on a predetermined route (for example, an overhead traveling vehicle, a trackless traveling vehicle traveling on a predetermined route, or a tracked traveling vehicle). Is also applicable.

First, the automatic guided vehicle system 1 will be briefly described with reference to FIG.
As shown in FIG. 1, the automatic guided vehicle system 1 is applied in an unmanned factory of a clean room such as a semiconductor manufacturing factory. In such an unmanned factory, stations 3 for processing an article 6 (for example, a wafer, see FIG. 3) are arranged at each point.
In addition, a traveling rail 2 that is a track is provided as a predetermined traveling route inside the unmanned factory. The automatic guided vehicle 10 receives the transfer of the pallet 7 (see FIG. 3) from the station 3, travels along the travel rail 2 to the other station 3, and transfers it.

Next, the communication means 25 will be briefly described with reference to FIG.
As shown in FIG. 2, the communication means 25 can communicate with the integrated controller 5 as an upper controller and the automatic guided vehicle controller 15 (not shown) by wireless communication using infrared communication or modem communication, or wired communication using a communication line. It is said that.
The integrated controller 5 is a controller that performs traveling control of each automatic guided vehicle 10... 10 in the automatic guided vehicle system 1. The integrated controller 5 includes a CPU that performs various arithmetic processes and controls, a ROM as a read-only storage unit, and a RAM as a readable / writable storage unit. In the ROM, an optimization program such as a production schedule is stored, and in the RAM, conveyance route information is written, and various information such as a traveling position and a control state of each automatic guided vehicle 10 is temporarily stored. The The CPU controls the entire automatic guided vehicle system 1 using the RAM as a work area according to a control program or the like written in the ROM.
On the other hand, the inter-cart communication means 27 can also communicate directly between the automatic guided vehicles 10. The inter-cart communication means 27 is configured to be communicable by infrared communication or the like.

  As shown in FIGS. 2 and 3, the automatic guided vehicle 10 has an arrow A in the drawing as a traveling direction. In the following, for easy understanding, a preceding preceding vehicle 10a1 and a preceding preceding vehicle 10a2 are defined with respect to a certain automatic guided vehicle (own vehicle) 10.

Next, the automatic guided vehicle 10 as a traveling vehicle will be briefly described with reference to FIG.
As shown in FIGS. 2 and 3, the automatic guided vehicle 10 moves between the stations 3 with the pallet 7 mounted thereon. An article 6 is stored in the pallet 7. The automatic guided vehicle 10 also includes a transfer device 12 for transferring the pallet 7 together with the station 3 at each station 3 and a traveling device 11 capable of traveling in an unmanned factory.
The transfer device 12 is configured such that, for example, a pair of roller conveyors (not shown) project from the lower part of the article storage space of the body frame. The pair of roller conveyors rolls on the lower surface of the pallet 7 and laterally feeds the article 6 in the left-right direction with respect to the traveling direction of the automatic guided vehicle 10 (the traveling direction of the traveling rail 2).
In this way, the automatic guided vehicle 10 according to the present embodiment has a general conveyance form in which a plurality of articles 6 are accommodated in the pallet 7 and conveyed. The form of the article 6 and the pallet 7 is not particularly limited.
Furthermore, the automatic guided vehicle 10 has a traveling position detection sensor (rotary encoder) 22 in the vicinity of the wheel, a vibration detector 21x parallel to the front-rear direction (traveling direction), and the left-right direction (vertical direction of the horizontal plane with respect to the traveling direction). The vibration detector 21y is provided in parallel with the vibration detector 21y, and the vibration detector 21z is provided in parallel with the vertical direction (the vertical direction of the vertical plane with respect to the traveling direction). Instead of the vibration detectors 21x, 21y, and 21z, the vibration detector 21 that can detect three directions with a single device may be used.

Next, the automatic guided vehicle controller 15 will be described in detail with reference to FIG.
As shown in FIG. 4, the automatic guided vehicle controller 15 is a controller provided in each automatic guided vehicle 10. The automatic guided vehicle controller 15 is connected to the vibration detectors 21 x, 21 y, 21 z, the travel position detection sensor 22, and the communication means 25.
The automatic guided vehicle controller 15 can communicate information detected by the vibration detectors 21 x, 21 y, 21 z and the travel position detection sensor 22 to the integrated controller 5 through the communication unit 25.

Next, the travel position detection sensor 22 (see FIGS. 3 and 4) as the travel position detection means will be briefly described.
In general, the automatic guided vehicle 10 can recognize which position it is currently traveling or working in the automatic guided vehicle system 1. For example, in the case of an automatic guided vehicle equipped with a rotary encoder that detects the rotation of the wheel, the travel distance can be calculated from the value of the rotary encoder, so the rotary encoder becomes the position detection sensor 25.
In the automatic guided vehicle system 1 in which the automatic guided vehicle 10 travels by spot guidance in which a magnetic spot is provided on the travel route, the magnetic sensor serves as the travel position detection sensor 22. Further, in the automatic guided vehicle system 1 in which the automatic guided vehicle 10 identifies the mark at an appropriate position on the traveling rail 2 by the CCD sensor, the CCD sensor becomes the traveling position detection sensor 22.
The automatic guided vehicle 10 is configured to communicate position information from the travel position detection sensor 22 to the integrated controller 5 to be described later, and recognize which position is currently traveling or working in the RAM.

Next, the vibration detectors 21x, 21y, and 21z (see FIGS. 3 and 4) as vibration detection means will be described in detail.
The vibration detector 21 of the present embodiment is a vibration detector that detects the vibration acceleration of an object, that is, detects the acceleration of the object by replacing it with a vibration value. The vibration detection means of the present invention is not limited to the vibration detectors 21x, 21y, and 21z of the present embodiment.
Usually, an object is supposed to measure vibrations in three directions, ie, a front-rear direction, a left-right direction, and a vertical direction. However, it has been found that the automatic guided vehicle 10 has particularly large vibrations in the left-right direction and the up-down direction.

Next, the vibration value g detected by the vibration detector 21 will be described in detail with reference to FIG.
As shown in FIG. 5, the vertical axis indicates the vibration value g, and the horizontal axis indicates the time series t. FIG. 5 shows a vibration value g of vibration generated in a certain automatic guided vehicle 10.
In the graph, gd represents a vibration value at a boundary whether or not to perform deceleration control described later. Usually, the automated guided vehicle 10 that travels travels with some vibration. For this reason, only the vibration value in the area of the predetermined vibration value gd or more generated by the rail / floor step is the target of the deceleration control.
A zone G1 in the graph indicates a vibration value zone determined as the vibration level G1 of the warning 1 level. A section G2 in the graph indicates a vibration value section determined as the vibration level G2 of the warning 2 level. Furthermore, a section G3 in the graph indicates a vibration value section that is determined to be an abnormal vibration level G3. The G3 level is assumed to be the vibration value level when an earthquake occurs.

Next, the deceleration level calculation means 26 will be described in detail with reference to FIG.
The deceleration level calculation means 26 is stored in advance in a ROM built in the integrated controller 5.
First, the deceleration level calculation means 26 determines the vibration level (G1, G2, or G3) if the vibration value by the vibration detector 21 described above is equal to or greater than gd. Further, the deceleration level calculation means 26 calculates a predetermined deceleration level A corresponding to each of the determined vibration levels G. The deceleration level A is set to increase the deceleration as the vibration level G increases. Here, since the deceleration level A3 corresponds to the G3 level that assumes the time of the occurrence of an earthquake, it is set to a deceleration level that can be stopped immediately.

Here, the deceleration control (S100 / S200) as the deceleration means of the present embodiment will be described with reference to FIGS.
In the deceleration control (S100 / S200), the vibration value detected by the vibration detector 21 and the traveling position detection sensor 22 of the preceding vehicle 10a1 or the preceding vehicle 10a2 and the position thereof are processed by the automatic guided vehicle controller 15 of the automatic guided vehicle 10. The vehicle 10 is decelerated at the position.
Hereinafter, as the two deceleration controls (S100 and S200), the predetermined level deceleration control (S100) as the first deceleration unit and the adaptive level deceleration control (S200) as the second deceleration unit will be described in detail.

First, the predetermined level deceleration control (S100) as the first deceleration means will be described in detail with reference to FIG.
As shown in FIG. 7, the deceleration control (S100) is a control for decelerating the automatic guided vehicle 10 by detecting vibrations of the preceding vehicle 10a1 and the automatic guided vehicle 10 itself.
First, the automatic guided vehicle controller 15 of the automatic guided vehicle 10 confirms whether or not the vibration detector 21 of the preceding vehicle 10a1 has detected a vibration value of gd or more (S110).
Here, the automatic guided vehicle controller 15 memorize | stores the detected travel position by the travel position detection sensor 22 of the preceding vehicle 10a1, when the vibration value more than gd is detected (S120). Next, the automatic guided vehicle controller 15 decelerates the own vehicle 10 at a predetermined deceleration level Ad set in advance at the travel position where the vibration is detected.
On the other hand, if no vibration value greater than or equal to gd is detected in S110, the automated guided vehicle controller 15 checks whether or not the vibration detector 21 of the own vehicle 10 has detected a vibration value greater than or equal to gd (S150). Here, the automatic guided vehicle controller 15 immediately decelerates the own vehicle 10 at a predetermined deceleration level Ad determined in advance when a vibration value equal to or greater than gd is detected (S160).
In S150, when no vibration value equal to or greater than gd is detected, the automatic guided vehicle controller 15 sets the own vehicle 10 to normal traveling control (S400).
It should be noted that the predetermined level deceleration control (S100) can be executed not by the automatic guided vehicle controller 15 but also by the integrated controller 5.

In this way, the following advantages can be obtained.
When the traveling rail 2 has an uneven portion, the automatic guided vehicle 10 is notified of the position by the preceding vehicle 10a1, and decelerates and travels at the predetermined deceleration level Ad set in advance so that vibration is reduced. be able to. The automatic guided vehicle (own vehicle) 10 that has detected the vibration can also travel at a reduced speed at a predetermined deceleration level Ad. For this reason, the vibration during driving | running | working is relieve | moderated and failure of the automatic guided vehicle (own vehicle) 10 and the damage of the article | item 6 or the collapse of the pallet 7 can be prevented.
Moreover, since the uneven | corrugated location of the running rail 2 in an unmanned factory can be detected early by the integrated controller 5 from the automatic guided vehicle controller 15, the location can be repaired immediately.
In this manner, the automatic guided vehicle system 1 can efficiently take measures against vibration.

Next, the adaptive level deceleration control (S200) as the second deceleration unit will be described in detail with reference to FIG.
As shown in FIG. 8, the adaptive level deceleration control (S200) performs the deceleration control at the deceleration level A corresponding to the vibration level G with respect to the predetermined level deceleration control (S100), and the deceleration value comparison control ( In S300), the deceleration control is performed by adding the two elements of checking the abnormality of the vibration detector 21.
First, the integrated controller 5 confirms whether or not the vibration detector 21 of the preceding vehicle 10a1 has detected a vibration value equal to or greater than gd (S210).
Here, when there is a detection of a vibration value equal to or greater than gd, the integrated controller 5 stores the detected travel position by the travel position detection sensor 22 of the preceding vehicle 10a1 (S220). Next, the integrated controller 5 calculates the deceleration level A corresponding to the detected vibration level G by the deceleration level calculation means 26 (S230). Here, the integrated controller 5 performs vibration value comparison control (S300) described later. Next, the integrated controller 5 decelerates the automatic guided vehicle (own vehicle) 10 at the calculated deceleration level A at the travel position where the vibration is detected.
On the other hand, if no vibration value greater than or equal to gd is detected in S210, the integrated controller 5 checks whether or not the vibration detector 21 of the automatic guided vehicle (own vehicle) 10 has detected a vibration value greater than or equal to gd ( S250). Here, the integrated controller 5 calculates the deceleration level A according to the detected vibration level G by the deceleration level calculation means 26, when the vibration value more than gd is detected (S260). Furthermore, the integrated controller 5 immediately decelerates the automatic guided vehicle (own vehicle) 10 at the calculated deceleration level A.
In S250, when no vibration value equal to or greater than gd is detected, the integrated controller 5 sets the automatic guided vehicle (own vehicle) 10 to normal traveling control (S400).

Next, vibration value comparison control (S300) as vibration value comparison means will be described in detail with reference to FIG.
As shown in FIG. 9, the vibration value comparison control (S300) compares the vibration values ga1 ′ and ga2 measured by the preceding vehicle 10a2 and the preceding vehicle 10a1 and confirms the abnormality of the vibration detector 21. Control.
First, the integrated controller 5 checks whether or not the preceding vehicle 10a2 and the preceding vehicle 10a1 have detected a vibration value gd or higher for performing deceleration control at the same travel position (S310). Next, if the integrated controller 5 is a vibration value when the preceding vehicle 10a1 is decelerated by the predetermined level deceleration control (S100) or the adaptive level deceleration control (S200), the vibration value ga1 ′ when there is no deceleration. Is estimated (S315). Next, the integrated controller 5 checks whether or not the difference between the vibration values ga1 ′ and ga2 is greater than or equal to the predetermined value α from S310 and S315 (S320).
Here, when the difference between the respective vibration values ga1 ′ and ga2 is equal to or larger than the predetermined value α, it is determined that any one of the vibration detectors 21 is erroneously detected or abnormal (S330). The reason for the large difference in the vibration measurement values at the same location is that it can be determined that either is abnormal.
On the other hand, the integrated controller 5 decelerates at the current deceleration level A when there is no vibration value equal to or greater than gd in S310 and when it is less than or equal to the predetermined value α in S320 (S270).

In this way, the adaptive level deceleration control (S200) can obtain the following advantages in addition to the effects of the predetermined level deceleration control (S100).
First, the automatic guided vehicle 10 can decelerate at a deceleration level A corresponding to the vibration level G. For this reason, it is possible to travel according to the cause of vibration generation. For example, since each automatic guided vehicle 10 stops traveling autonomously when an earthquake occurs, all automatic guided vehicles 10 can be stopped immediately. Further, when the vibration level G is small, the deceleration level A is also controlled to be small, so that a reduction in the operation rate of the automatic guided vehicle system 1 can be minimized.
In addition, since a false detection or abnormality of the vibration detector 21 can be detected immediately, a maintenance instruction or the like can minimize a reduction in the operating rate of the automatic guided vehicle system 1.

The block diagram which shows the whole structure of the automatic guided vehicle system which concerns on a present Example. The block diagram which similarly shows the communication means structure of an automatic guided vehicle system. The perspective view which similarly shows an automatic guided vehicle. The block diagram which similarly shows an automatic guided vehicle controller. The graph which shows the vibration level which a vibration detector detects. The table figure which shows the correlation with a vibration level and a deceleration level. The flowchart which shows the flow of the predetermined deceleration control of a present Example. The flow figure which shows the flow of adaptive level deceleration control similarly. Similarly, the flowchart which shows the flow of vibration value comparison control.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Automated guided vehicle system 2 Traveling rail 3 Station 5 Integrated controller 10 Automated guided vehicle 15 Automated guided vehicle controller 21 Vibration detector 22 Traveling position detection sensor 25 Communication means 26 Deceleration level calculation means S100 Predetermined level deceleration control S200 Adaptive level deceleration control S300 Vibration value comparison control

Claims (3)

In a traveling vehicle system having a plurality of traveling vehicles traveling along a predetermined traveling route,
The traveling vehicle is
Vibration detecting means for detecting a vibration value;
Traveling position detection means for detecting the current traveling position;
Communication means for communicating a running position at which a vibration value equal to or greater than a predetermined value is detected by the vibration detecting means and the running position detecting means to a following traveling vehicle;
First speed reduction means for decelerating the travel speed when traveling at the position when the travel position at which a vibration value greater than or equal to a predetermined value is detected by the communication means of the preceding traveling vehicle;
Vibration value comparison means for comparing the vibration value detected by the vibration detection means of the own vehicle with the vibration value assumed from the vibration value detected by the vibration detection means of the preceding traveling vehicle;
A traveling vehicle system comprising: The traveling vehicle system according to claim 1,
When the traveling vehicle detects a vibration value of a predetermined value or more by the vibration detecting means of the own vehicle,
A traveling vehicle system comprising second deceleration means for decelerating the traveling speed of the host vehicle. In the traveling vehicle system according to claim 1 or 2,
A vibration level detected by the vibration detection unit is divided into a plurality of levels, and a deceleration level calculation unit that decelerates the traveling speed according to the vibration value level is provided.
The traveling vehicle system, wherein the first or second deceleration means decelerates according to the deceleration level calculated by the deceleration level calculation means.

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