JPS6373303A - Control system for autopilot vehicle at intersection - Google Patents

Abstract

PURPOSE:To prevent the collision of vehicles in an intersection, by detecting the arrival of an autopilot vehicle at an intersection area, identifying the presence/absence of other autopilot vehicles in the area by receiving transmission waves from the vehicles, and transmitting an intermittent wave in the area. CONSTITUTION:The autopilot vehicles A, B, and C running traveling paths L11, L1, and L12, advance to the intersection area P1. A confirmation area S1 is provided at a prescribed range of the outside of the area P1. Optical reflecting tapes a1-d1, and a2-d2 having prescribed lengths, are installed in parallel with an optical guide tape installed on the traveling path. The vehicle A detects the tape a2 by a receiver loaded on the vehicle A, and confirms the advancement to the area S1, and after entering, identifies the presence/absence of the vehicles in the area by receiving the wave signals emitted from the vehicles B, and C, and judges a priority order. When it is judged that no other vehicles are present in the area, the vehicle A advances the area P1, and transmits an intermittent wave signal representing the presence in the area, and terminates the emission of the intermittent wave signal after passing the area.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application The present invention relates to an intersection control system for automatically piloted vehicles used in factories and the like.

BACKGROUND OF THE INVENTION Conventionally, autopiloted vehicles have been used to travel within factories, etc., and when multiple autopiloted vehicles are used at the same time, intersections, branching points, or merging points (hereinafter collectively defined as intersections) of travel routes are used. ), when there is only one intersection between multiple self-controlled vehicles, one example of an intersection control method is to give priority to one self-controlled vehicle and keep the other self-controlled vehicles on standby. A control method as shown in the figure is used.

In the figure, the intersection of the driving path is 0, the driving path is Ll, Ll
, Ls and L4, the control area of the intersection is designated as D, and all the intersections of the intersection control area D with the travel routes Ll, L2°Ls and L4 are respectively C1, C2, C3 and C4. Now, the autopilot vehicle pattern has arrived at this intersection C1, and the autopilot vehicle B
Consider the state tQt- which is approaching the intersection C2.

SL, 82, 83, and S4 are intersection control devices consisting of photoelectric detection devices installed on the fixed side (ground side), and when the autopilot vehicle stops at this control device, the autopilot vehicle and the intersection control device It is something that can be given and received.

S is an intersection control panel, and each control device S1. This is a control panel that performs intersection control based on signals S2°83 and S4.

The autopilot vehicle reaches the intersection C1 and the intersection control device S
1, and when no other autopiloted vehicle is running within the intersection area D, the autopilot vehicle is given a permission signal to enter the intersection control area D from the control table wt81. Enter the intersection.

When the autopilot vehicle B is traveling within the intersection area D, the autopilot vehicle B cannot enter the intersection area D even if it reaches the intersection and stops at the position indicated by the control table @82.

The autopilot vehicle A travels, passes through the intersection area D4 and reaches the intersection C4 as shown by the dotted line in Figure 2, exchanges signals with the control device S4, and the auto-NM vehicle A moves to the intersection area D'.
f! :Informs you that it has passed.

In response to this signal, the autopilot vehicle B is given a signal by the control device S2 that allows it to enter the intersection area D, and starts traveling into the intersection area D.

In this way, the automatically piloted vehicle approaching the intersection area can sequentially exchange signals with the intersection control device and travel.

However, this control method requires a control device and a control panel on the fixed side (ground side) to exchange signals with the automatically piloted vehicle, and this device is required at each intersection area and each intersection of the travel route. Therefore, there was a problem in that the device became very complicated and required construction work, which required a large amount of cost.

Furthermore, when changing the location of an intersection due to changes in the system layout, etc., it is not easy to change the equipment, and there is a problem that the system lacks flexibility.

Problems to be Solved by the Invention In view of the above-mentioned circumstances, the present invention provides a simple structure that eliminates the need for fixed side (ground side) equipment at intersections for automatically piloted vehicles, and is also adaptable to changes in system layout. The purpose is to provide a control method.

Means for Solving the Problems The present invention is an intersection control method for a system having a plurality of autopiloted vehicles that simultaneously travel automatically along a travel route. A detection means that detects whether the vehicle has passed or has passed, and the detection means sets the state in which all radio signals emitted from other autopilot vehicles located within the corresponding intersection area are received, and when the vehicle enters the intersection area, the reception state is completely stopped. a receiving means for determining the presence or absence of other automatically piloted vehicles within the intersection area by the receiving means; and a means for determining the priority order for entering the intersection, means to completely prevent entry into the intersection area, and to start intermittent transmission 1i- of a radio wave signal at a predetermined period indicating that the intersection area is within a predetermined area determined in advance for each intersection area when entering the intersection area; This is an intersection control method for an automatically piloted vehicle, characterized by comprising a transmitter that stops transmission when passing through an area, and a means that controls the travel of the automatically piloted vehicle based on an output signal from the receiver.

EXAMPLES Below, examples of the present invention will be explained based on the drawings.

An explanation will be given of the case where there are n intersection areas from PL to P2, river, .

L l, L 11. Llg-・-Lnl, Ln
2. Lns etc. indicate the route of the automatically piloted vehicle. This running route Ll, L↓l.

L12... Lml, Lmg, Lm3
For example, an optical guidance tape is laid down on the road, and the autopilot vehicle automatically travels along the guidance tape.

The control system of the autopilot vehicle will be explained based on FIGS. 4 and 5.

FIG. 4 is a diagram showing an embodiment of a control system for an automatically piloted vehicle for realizing the intersection control method of the present invention, and FIG. 5 is a diagram showing a detailed embodiment of the intersection control circuit in FIG. 4. be.

Reference numeral 21 designates a guidance detection device that detects a guidance tape, and 22 designates a control section that is composed of a logic judgment section 221 and a steering control section 222. This is a control device that allows an autopilot vehicle to travel automatically according to predetermined processing procedures.

The drive control section n includes a steering motor drive circuit 231 that drives the steering motor 24 via the control section 22, and a travel motor drive circuit 232 that drives the travel motor 26. Potentimeter 5 for measuring the rotation speed of the steering motor
is connected to the drive wheels of the steering motor 5, and the output of the potentiometer 5 is fed back to the control section 22 to ensure stability of control. By driving the steering motor 26 and the travel motor 26t, the automatically piloted vehicle can be driven along the travel path. 30 is an intersection control circuit, including a transmitter 311 that transmits all radio waves, a transmitter circuit 312, and a receiver 1g that receives radio waves! A321, a receiving circuit 322, and a signal processing circuit 301.

FIG. 5 shows details of the intersection control circuit (branch). Based on the output from the control unit 22, the transmission circuit 312 transmits information to the intersection areas PL, P via the signal processing circuit 301t.
g... Frequency selection and transmission period selection signal circuit 333 that selects the frequency of a predetermined radio wave to be transmitted corresponding to each Pm; Frequency selection and transmission period selection signal circuit 33
The transmission frequency fl is based on the signal of 3.

The transmitter 31 is composed of a frequency switching circuit 333 that switches and selects a circuit for emitting radio waves of a predetermined frequency from the radio wave generator of f2...fn, and a modulation circuit 331.
1 to transmit radio waves to the outside.

The reception circuit 322 includes a demodulation circuit 341 that demodulates the signal from the receiver 321 that receives radio waves, and a demodulation circuit 341 that demodulates the signal from the receiver 321 that receives radio waves, and the frequency of the received radio waves as f,, fj! . . . A frequency discrimination circuit 342 that discriminates which one is fn, and a frequency discrimination circuit 3
Intersection area internal area identification circuit 3 that identifies which intersection area the signal is located based on the frequency determined in step 42.
43, and the identified local signal is sent to the signal processing circuit 3.
01 to the control unit 22 to enable intersection control at each preset intersection. The frequency of the radio waves of the local signal emitted by the autopilot vehicle in the intersection area PL is fl, the transmission frequency when the vehicle is in the intersection area P2 is f2, and the following sequentially the frequency of the local signal in the intersection area Pn. The transmission frequency is predetermined as fn.

When determining the transmission frequency, select a frequency that does not interfere between intersection areas.

In addition, in this embodiment, to identify each intersection area, the transmission frequency is set to fl, fg, etc. corresponding to each intersection area.
fn, but it is also possible to identify the intersection area by modulating a pulse signal for each predetermined intersection area into the transmitted radio wave without changing the frequency.

The operation of intersection control in the intersection area PL on the travel route shown in FIG. 3 will be explained based on FIG. 1.

An autopilot vehicle traveling on the driving path Lllk and entering the intersection area PIVc is a person, and an autopilot vehicle traveling on the driving path Llt- and entering the intersection area P1 is 1kB.

Let us assume that the autopilot vehicle 1c is traveling on the driving path L1zt and entering the intersection area Pl. An entry confirmation area 51t is provided in a predetermined range outside the intersection area P1. Intersection point t-Pa1. between intersection area P1 and travel path Lll, Ll, L12°Ll. P'bl, Pcl, Pd1, intersection with approach confirmation area S1 t-8ag, 8'bg
, 8cg, and 8dg.

In the figure, al, bl, C1 and dl#"l: Optical reflective tape of a predetermined length is laid parallel to the optical guidance tape laid on the driving route, and the autopilot vehicle is guided to the intersection area PL.
This is a detected object for detecting that the vehicle has reached the intersection area PL' and has passed through the intersection area PL'.

Also, a2. b, g, and C2 are optical reflective tapes of a predetermined length that are laid parallel to the optical guidance tape laid on the driving route, and are detected objects for detecting that the autopilot vehicle has reached the entry confirmation area S1. be.

The autopilot vehicle detects each detected object al, bl, C1゜dlt.
aj! , bg and C211: Can be detected by the guidance detection device [121]. Intersection area P for the case where the autopilot vehicle artist first reaches the entry confirmation area s1, and then the autopilot vehicle B and the autopilot vehicle C arrive.
The operation at L will be explained.

The operation will be explained below based on FIG.

Step 50: The autopilot car artist starts driving along the driving path Lll.
1) When tape agi is detected, enter confirmation area S1
, and it is detected that the intersection point sag has been reached (step 502).

When the autopilot vehicle reaches the intersection 8ag, the receiver 321
'k is set to the "receiving mode" which is the ON state (step 503), so that it can receive the present signal sent by other automatically piloted vehicles in the intersection area P1, and other preceding vehicles in the intersection area Pi. The presence or absence of an autopilot vehicle is determined (step 504).

If the presence signal is not received, there will be no other autopiloted vehicle within the intersection area Pl, so the autopilot vehicle continues to drive along the travel path Lll toward the intersection area Pl (step 5o5).

When the presence signal is received, another autopilot vehicle will be in the intersection area Pl, so the autopilot vehicle reaches the intersection area P1, and at that time, the autopilot vehicle reaches the intersection area Pl.
If another autopilot vehicle is present within the area, the intersection area P1
Since it is not possible to enter the intersection and it is necessary to stop at intersection Pa1,
In that case, the intersection
Decrease the traveling speed with ag and move towards the intersection Pa1 on the traveling path Ll
1 (step 506).

When the autopilot vehicle operator detects the tape alt, it reaches the intersection area PL and fully detects that it has reached the intersection Pa1 (step 507).

When reaching the intersection Pal, it is determined whether or not there are other autopiloted vehicles ahead within the intersection area P1, depending on whether all the current signals are received (step 508).

If the autopilot vehicle operator does not receive the present signal, there is no other autopilot vehicle ahead in the intersection area PL, so the autopilot vehicle A is set to "sending mode" and moves to the intersection area P.
1, and at the same time, the "receiving mode" is canceled (step 510).

FIG. 7 shows the state of the signals transmitted by the autopilot vehicle when the "transmission mode" is set. The frequency of the outgoing signal is fl, f2...fn corresponding to each intersection area, and in the intersection area P1 of this embodiment, the outgoing frequency is fl.
shall be. Furthermore, this transmission signal is assumed to have a predetermined period tn6 in which the signal is transmitted for a certain period of time t and the transmission is stopped for the remaining time, and this transmission signal is transmitted intermittently every period tn.

Here, the time t for transmitting the signal is the same for each autopilot vehicle, and the period tn is a different time for each autopilot vehicle,
For example, autopilot vehicle A is tl, autopilot vehicle BFitz
, an autopilot vehicle C#'its song.

Therefore, by receiving this transmission signal, each autopilot vehicle can determine which autopilot vehicle in which intersection area is present.

Also, during the time period (tn-t) when no signal is transmitted, the vehicle is in a state where it can receive the active signals of other automatically piloted vehicles.

When the autopilot vehicle operator receives the signal, it means that there is another autopilot vehicle ahead within the intersection area PL.
Since the autopilot vehicle A cannot enter the intersection area Pl, it waits until it no longer receives the presence signal at the intersection area population Pa1 (step 509).

The autopilot vehicle A enters the intersection area PI while transmitting an intermittent signal (step 511) and continues to drive within the intersection area PI while determining whether or not the presence signal is received. When the tape dll) is detected, it is detected that the intersection Pdx [has been reached, and it is determined that the intersection area Plt- has escaped (step 512
).

When the autopilot vehicle A receives the presence signal while traveling in the intersection area P1=i, the autopilot vehicle A stops traveling and stops at that position (step 513).

Then, the autopilot car artist sets the "reception mode" and cancels the "transmission mode" to stop the transmission (step 514), and then receives the presence signal (step 5).
15) When the present signal disappears, the vehicle is set to the "calling mode" again and starts entering the intersection area P1 (step 510).

When the autopilot vehicle determines that the person has escaped from the intersection area Pli, it cancels the "transmission mode" and stops the transmission (step 516), and starts normal travel along the travel path Ll (step 517).

FIG. 8 shows the states of each mode from when the autopilot vehicle reaches the entry confirmation area S1 to when it escapes to the intersection area pH. When reaching the intersection 8ag, the vehicle enters the "receiving mode" and becomes ready to receive signals from other autopilot vehicles.

When it reaches the intersection Pal, it switches to the "transmission mode" and the seventh
An intermittent signal is transmitted at the frequency f1 explained in the diagram for a certain period of time t with a period of tl, and at the time (tl-t), the autopilot vehicle A is in a state where it can receive the in-service signal, and the autopilot vehicle A enters the intersection area PL. enter in.

In Fig. 8, the time td is provided so that when an intermittent signal transmitted by each autopilot vehicle is received, it can be treated as a continuous received signal, and the relationship between td and the maximum period tnMAX of the intermittent signal is as follows. td) tn MAX.

According to this embodiment, it is possible to receive the signals of other autopiloted vehicles even while driving in the intersection area P1, and even if multiple autopiloted vehicles enter the same intersection area, only one
It is possible to prevent collisions between autopiloted vehicles by allowing only one autopiloted vehicle to enter and stopping other autopiloted vehicles in that position.

When the autopilot vehicle reaches the intersection Pd1, the driver moves to the intersection area P.
1=j (Since it means that the vehicle has escaped, ■ "transmission mode" is canceled, and ■ "l'-NULL mode" is set.) It becomes a state in which it neither transmits nor receives data, and starts running normally.

When the autopilot vehicle exits from the intersection area P1t, another autopilot vehicle that can enter the intersection area P1 with priority next can enter the intersection area P1 after a predetermined period of time has elapsed.

In this embodiment, the order of priority for entering the intersection area P1 is the order in which the entrance to the intersection area is reached earlier in time, and if the arrival times are at the same time, for example, the transmission cycle is tl, tl, t3, etc. ...tn order, and a priority order is determined in advance for each autopilot vehicle.

Of course, this priority order can be achieved by arbitrarily setting the transmission cycle.

In this embodiment, the autopilot vehicle B and the autopilot vehicle C simultaneously enter the entry confirmation area S1 while following the autopilot vehicle person.
, each travels on the road, and at the same time reaches the intersection area P.
I will explain what happens when the population reaches 1. Further, it is assumed that the priority is given to the autopilot vehicle B between the autopilot vehicle B and the autopilot vehicle C. The mode of each autopilot vehicle in this case and the signal reception status at each point are shown in Figure 9.
FIG. 9 (■) shows the case of the autopilot vehicle being a person, FIG. 9 (■) shows the case of the autopilot vehicle B, and FIG. 9 (■) shows the case of the autopilot vehicle C.

Now, when the autopilot vehicle B travels along the travel path Llt and reaches the intersection 8b2 with the entry confirmation area sl, it is set to the reception mode j and moves to the intersection area P1 while checking the presence or absence of the presence signal of other autopilot vehicles. Intersection point Pb:t which is the entrance of
Drive towards K. Since the autopilot vehicle receives the human presence signal by the time it reaches the intersection Pb1, the intersection area Pl
Since the vehicle cannot enter the intersection, it stops at the intersection P'bl and waits. In addition, when the autopilot vehicle C travels along the driving path Llz Th and reaches the intersection point 8cg with the entry confirmation area S1, it is set to "receiving mode" and moves to the intersection area P1 while checking the presence or absence of the presence signal of other autopilot vehicles. The intersection point PCI is the entrance of
drive towards. Since the autopilot vehicle receives the human presence signal by the time it reaches the intersection PCI, the intersection area Pl
Since it cannot enter the area, it stops at the intersection PCI and waits.

Next, when the autopilot vehicle person escapes from the intersection area PL, the autopilot vehicle B and autopilot vehicle C will no longer receive the service signal, so the autopilot vehicle B and the autopilot vehicle C will no longer receive the service signal.
d Transition husband Husband Switch to "transmission mode" and set the predetermined period tl
The vehicle attempts to enter into the intersection area Pl by repeating intermittent transmission of tlt and tlt. At this time, since the autopilot vehicle B comes first in priority order to the intersection area Pl, the relationship between the cycles of the intermittent signals is t z (t s ), and the intermittent signals of each autopilot vehicle are as shown in Figure 8. At the time indicated by ■, autopiloted vehicle C receives the signal gold signal of autopiloted vehicle B, which has not been previously transmitted.Therefore, autopiloted vehicle C stops at that position and receives [ reception mode -].The autopilot vehicle B is in Somaichi intersection area Pl.
go inside.

Then, the vehicle traveled L1ft on the driving path, reached the intersection Pdx, and escaped from the intersection area P1. 6.Konaha canceled the "transmission mode" and entered the "NULL mode", and did not make any transmissions or receive any signals. Then, normal driving begins.

Autopilot vehicle C, after time td has elapsed since it stopped receiving all signals from the autopilot vehicle, switched to "transmission mode" and repeatedly transmitted intermittent transmissions with a predetermined period t3, entering the intersection area Pl? It starts, but it stops at that position because it receives the in-service signal sent by autopilot vehicle B, completely cancels the "sending mode", switches to the "receiving mode", and waits.

When the autopilot vehicle B escapes from the intersection area Px2, it will stop transmitting the in-service signal, so the auto-piloted vehicle C will receive all the in-service signals (since it will no longer be available, it will switch to the [transmission mode] again.) It will have a predetermined period t3tr within the small intersection area Pl. Repeating the intermittent transmission, the driver travels from the driving path L12 to the driving path 1, and reaches the intersection P d 1.
Now that you have escaped, cancel the "outgoing mode" and press l'
-NULL mode", the vehicle enters a state where it does not make any calls or receive calls, and starts normal driving.

Therefore, within the intersection area P1, each of the three autopilot vehicles A, B, and C can perform intersection control according to the respective determined priority order.

In addition, in this embodiment, the priority order within the intersection area PL is predetermined for each autopilot vehicle, but this priority order is determined not for each autopilot vehicle but for the priority order within the intersection area PL. It is also possible to predetermine the priority order for each travel route.

For example, in the 1st N, each travel path Lll, LX and LI!
! The signal sent by the autopiloted vehicle that has reached the point is shown in Figure 10, and the time tμ for all the signals to be sent is the same for all autopiloted vehicles, and the period tn is a different time for each traveling route.
For example, running route 1.]l is t]1, running route Ll#it! ,
The running route Lll is assumed to be t3. Priority order t-tl, tg,
It is also possible to set the priority order in advance for each travel route.

In this case, each traveling route L in the intersection area P1
The three autopilot vehicles, B and C, which have arrived at Ill, Ll and Llz, can perform intersection control in the same manner as in the above-described embodiment according to their respective predetermined priority orders.

In the same way as the control method in the intersection area PI described above, intersection control can be performed in the other intersection areas P2...P2 shown in FIG. 3 as well.

With the above operation, even if there are multiple intersection areas on the driving route, when the autopilot vehicle traveling on the driving path approaches the intersection, the detection function is applied to each intersection of the fixed side (ground side) intersection area and the approach area. This is a control system that can efficiently control intersections with a simple configuration of simply laying tape and installing a radio wave transmitter and receiver in an automatically piloted vehicle, and can also respond quickly to changes in system layout.

(2) In this example, an optical guidance tape was used to guide the automatically piloted vehicle along the travel path, but the method for guiding the travel path is not limited to this, and electromagnetic induction and laser Of course, this can be done by induction or the like.

Further, the use of an optical reflective tape as a detected object for detecting arrival and passage through an intersection area is not limited to this, and it is of course possible to use a detection device such as a proximity switch.

Effects of the Invention According to the present invention, intersection control for automatically piloted vehicles can be performed even if there are multiple intersections with a simple configuration without requiring any special equipment on the fixed side (ground side). Since a collision can be prevented even if an automatically piloted vehicle enters the intersection, it is possible to provide an intersection control method that is highly reliable and can be operated efficiently.

[Brief explanation of the drawing]

Fig. 1 is an explanatory diagram showing the intersection control system of the present invention, Fig. 2 is an explanatory diagram showing the conventional intersection control system, Fig. 3 is an illustration of an embodiment of the driving route, and Figs. A circuit diagram showing the control system of an automatically piloted vehicle to realize the invention control method, Fig. 6 is an explanatory diagram of the operation, Fig. 7 is an explanatory diagram of the emitted signal when driving in an intersection area, and Fig. 8 is the emitted signal and the received signal. FIG. 9 is an explanatory diagram showing the mode of each autopilot vehicle and the signal reception status at each point. FIG. 1O is an explanatory diagram of the signal transmitted when driving in an intersection area. Ll, Lll, L12... driving route, A and B are automatically piloted vehicles, D is an intersection area, (capital) is an intersection control circuit, 311 is a transmitter, 321 is a receiver. Patent applicant: Kinsha, Hitachi Kiyoshi Kogyo Co., Ltd. Representative: Kiyoaki Hayashi (1 person) Procedural amendment stamped April 24, 1985 Commissioner of the Patent Office Kuro 1) Akio Tono 2. Title of invention: Autopilot vehicle intersection Control method 3, relationship with the case of the person making the amendment Patent applicant: 3-11-1 F Sakabe, Amagasaki City, Hyogo Prefecture Hitachi Kiden Kogyo Co., Ltd. 4, Agent 5, Subject of amendment 1, Specification page 6, line 13 8th page 81i[''r
Correct "P m J" to "rPn" respectively. 2, same page, line 17 rLm,,Lm2. I, m3J should be corrected as rLn, , Lna + Lna j. 3. Page 8, line 11, "Signal circuit 333" r 1
i1 circuit 332”. 4. On page 21, line 12, correct "P2" to "rPn". 5. Page 23, line 8 rA and B are automatic.'' rA. "B and C are automatic," he corrected. 6. Correct Figure 4 in the drawings as shown in the attached sheet.

Claims (1)

[Claims] (1) An intersection control method for a system having multiple automatically operated vehicles that simultaneously travel automatically along a travel route,
A detection means provided in the autopilot vehicle detects arrival at and passing through an intersection area, and the detection means receives radio signals emitted from other autopilot vehicles located within the corresponding intersection area. and a receiving means that stops the reception state when entering an intersection area, a means that uses the receiving means to identify the presence or absence of another automatically piloted vehicle within the intersection area, and a means that determines a priority order for entering the intersection. , and a means for preventing multiple automatically piloted vehicles from entering an intersection area, and a predetermined radio signal that indicates that the vehicle is in a predetermined area predetermined for each intersection area when the vehicle enters the intersection area. An autopilot system comprising: a transmitting unit that starts intermittent transmission at a certain interval and stops the transmission when passing an intersection area; and a unit that controls the running of the autopilot vehicle based on the output signal of the receiving unit. Vehicle intersection control method.