JPS6048800B2 - Road traffic flow control method - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a road traffic flow control system, and more particularly to a system for providing vehicles with optimal route information from their local point to a destination point to smoothly control traffic flow.

Route guidance systems are one means of smoothing traffic flow in urban road networks. This guides each vehicle to its destination on the optimal route according to traffic conditions. In such systems, the optimal route for each vehicle is determined online, and the driver is generally notified of the optimal route to follow at each intersection. However, when a vehicle is detoured due to an accident or other sudden traffic jam occurring on the route, the driver does not know the reason. There is a possibility that they will not be able to understand the situation and become anxious. Therefore, it is desirable to inform the driver of the optimal route as well as the traffic congestion situation on the main route to the destination. However, on a large road network, the main route for any combination of starting point and destination is determined, and the main route is determined on that route! When attempting to perform data processing to determine traffic congestion using a computer program, the problem was that the calculation time would be enormous. An object of the present invention is to provide road traffic flow control that can quickly obtain optimal route information from a vehicle's local point to a destination point in accordance with the congestion situation of the road network, which should be provided to vehicles traveling within the road network. The purpose is to provide a method.

The present invention is characterized by having a ground device installed at a predetermined point on a road network, a central processing unit, and an on-vehicle device mounted on a vehicle, the on-vehicle device being a When doing so, it receives a location code uniquely assigned to that location from the ground device at that location, and transmits it to the central processing unit along with the location code of the destination point that the driver has set in advance in the on-vehicle device. and a transmitting means for receiving the route guidance information sent from the central processing unit and notifying the driver of the information, and the central processing unit is configured to provide information on route guidance between each point in the road network in advance. at least one congestion situation determining means for searching for the shortest time route from the passing point of the point code sent from the in-vehicle device to the destination point based on the given travel time and congestion situation data; and the gate congestion situation. and means for transmitting the output of the determining means to the in-vehicle device as the route guidance information.

This will be explained below with reference to the drawings.

FIG. 1 schematically shows the overall configuration of the present invention. In the figure, 1 indicates a point code transmitting device, which is installed at a predetermined point on a road network and is uniquely assigned to each point. The point code is transmitted to a vehicle 3 passing through the point via a ground antenna 2 buried in the road.

The vehicle 3 is equipped with an on-vehicle device to be described later, which receives the location code and transmits predetermined information to the central processing unit 5 via the on-vehicle antenna 4. 6 is an antenna provided in the central processing unit 5.

The central processing unit 5 performs predetermined processing based on the information received from the vehicle 3 and transmits it to the vehicle 3 as guidance information for guiding the vehicle 3 to the destination point along an optimal route. The vehicle 3 receives the information and transmits the information to the driver using the transmission device of the on-vehicle device. FIG. 2 shows the configuration of the vehicle-mounted device.

In the figure, 7 indicates an antenna (not shown in FIG. 1) for receiving a point code sent from the point code transmitter 1 via the ground antenna 2, and 8 indicates a receiver therefor. 9 is a register for storing the received location code.

The point code stored in this register 9 is always the point code indicating the current location of the vehicle 3, and this point becomes the departure point code for the shortest time route search, which will be described later. Therefore, this register 9 is called a departure point code register. Reference numeral 10 denotes a destination point code register, which stores the point code of a point previously set as a destination by the driver.

The point codes stored in these two registers 9 and 10 are transmitted by the transmitter 11 to the central processing unit 5 via the on-board antenna 4. Further, information sent from the central processing unit 5 is received by the receiver 12 via the on-board antenna 4, and is transmitted to the driver by the transmission device 13. FIG. 3 shows an example of the configuration of the central processing unit 5. As shown in FIG.

In the figure, a receiver 14 receives the departure point code and destination point code sent from the vehicle 3 via the antenna 6. The received set of location codes is temporarily stored in the reception buffer register 15. 16 is a distributor;
Reference numeral 17 indicates a congestion situation determination device.

The congestion situation determination device 17, which will be described in detail later, searches for the shortest route from the departure point to the destination point based on the above-mentioned set of received point codes while taking into consideration the degree of congestion during that time. . In addition, the determination device 17 determines, depending on the scale of the road network, the amount of service vehicles within the road network, etc.
Multiple units are available that can be operated in parallel. Therefore, the received point data is temporarily stored in the reception buffer register 15 and sent by the distributor 16 to the vacant congestion situation determining device 17. At that time, if there is no vacant congestion status determination device 17, the received point data will wait in the reception buffer register 15. In order to search for the shortest time route, the congestion situation determination device 17 is given the travel time required between all adjacent points in the road network by the arc cost setting device 18.
Various methods have already been proposed for measuring the travel time between points, so they will not be described in detail here. The results of the congestion situation determination device 17 are sequentially stored in the transmission buffer register 19 and transmitted to the vehicle 3 by the transmitter 20 via the antenna 6.

Further, data received from vehicles that have been processed by the congestion situation determination device 17 are sequentially deleted from the reception buffer register 15. The signal to be transmitted to the vehicle 3 may be a signal that is displayed on the transmission device 13 in the form of instructions such as turning right, turning left, or going straight at each point on the travel route, or in the form of letters or figures. Similarly, a voice synthesis device 21 may be provided to transmit the output of the congestion situation determining device 17 to the vehicle 3 as voice guidance. In this case, the driver is given a voice instruction from the transmission device 13, such as, for example, ``There is a traffic jam in the XX direction due to an accident, so please take a detour to the XX direction.'' Next, the congestion situation determination device 17 will be explained.

Consider a road network model as shown in Figure 4a. In the figure, A-I indicates a point (node) set in the road network, such as an intersection, and each of these has a point code transmitter 1 and a point code transmitter 1, as described in relation to FIG. A ground antenna 2 is installed. In addition, lines connecting each point (
Arc) means a road section, and each road section is given the time (arc cost) required to travel between them. In the figure, the arc cost is shown with lowercase letters of the alphabet indicating both end nodes of each arc. FIG. 4b shows the configuration of the congestion situation determination device 17 applied to the road network having the shape described above.

In the figure, 25 is an input/output device, and 26 is a control circuit. 27A to 271 indicate point modules, these are:
Each corresponds to point A-I in FIG. 4a.

These point modules are connected by a trip signal line 28 indicated by a thick line. Furthermore, each point module 27
Clock pulses of a predetermined period are applied to A-271 from the clock pulse generation circuit 30 via the synchronization signal line 29. Further, each of the point modules 27A to 271 exchanges signals with the input/output device 25 via the input/output signal line 31. Some of this signal is given from the arc cost setting device 18 mentioned above, and includes
The signal for setting the arc cost in A~271,
It includes signals to be read from each point module 27A to 27I and sent to the transmission buffer register 19 as shortest time route information. The configuration of the point module is as shown in FIG.

In the figure, 32 indicates an arc module, and a plurality of arc modules 32 are prepared in advance in one point module. Since all of those arc modules 32 have the same configuration, the specific configuration of only one arc module 32 is shown in the figure. Each of these arc modules 32, with a trip signal line 28 connected thereto,
There is a one-to-one correspondence with the arcs connected to the corresponding points A--I of 7A to 271. Within the arc module 32, 33 and 34 indicate arc cost registers, in which the arc cost of the corresponding arc is set via a wire 31 connected to the input/output device 25.

Of these, the register 33 contains the standard traveling time (arc cost) required to travel the corresponding arc (i.e. road section), and the register 34 contains the ever-changing arc cost of the same arc. The arc cost of the register 34 is updated by, for example,
It is performed every 3 minutes, every 3 minutes, or every 3 minutes. A flag 35 is set when the contents of the registers 33 and 34 become zero, and outputs an output signal.

36 is a congestion degree register in which a code indicating a corresponding arc and a congestion degree register of that arc are stored.

The congestion degree data is calculated as follows when the traffic condition of the relevant arc is normal.
0. j, "1" is selected when there is a slight traffic jam, "2" is selected when there is a heavy traffic jam, and "3" is selected when an accident has occurred. This data is also updated via the line 31 by the input/output device 25 at predetermined time intervals or as appropriate. 37 indicates a gate.

Furthermore, 38 indicates an arrival detection circuit, which is turned on only in the point module corresponding to the destination point.
All others are kept off.

When the arrival detection circuit 38 is in the on state, the propagated signal is blocked there. 39 is the destination point register, 4
0 is the starting point register, respectively. The point code of the corresponding point of the point module is stored in advance, and when the destination point code and departure point code are sent via the line 31, when they match the point code stored in advance. output signal to.

41 is a gate, and 43, 4!4, and 45 are OR circuits.

Next, the first operation of the congestion situation determining device 17 as described above will be explained.

First, the input/output device 25 performs initial settings.

First, as mentioned above, all points -. The standard arc cost j is stored in the register 33 in the corresponding arc module 32 of the I modules 27A to 271, and the shortest time route search is stored in the register 34. The arc costs for each time slot are stored. Next, the gates 41 of all point modules 27A-27I are opened, the gates 37 of all arc modules 32 are closed, and the register 35 is reset. In addition, the arrival detection circuit 38 of one point module corresponding to the destination change
Only one is turned on, and all others are turned off. This is transmitted from the input/output device 25 to each point module 27A to 2.
This can be done by specifying the address attached to 7I. After the above preparations, the first step is to start searching for the shortest time route.

First, the point code of the departure point is sent from the input/output device 25 to each point module 27A to 271 through the signal line 31.

The output of only the register 40 in which the land change code given by this input signal matches the land change code stored therein is turned on. The signal passes through the OR circuit 45 and is output as a trip signal from the point module corresponding to the starting point. This trip signal propagates downstream through trip signal line 28 to arc module 32 . A trip signal arriving at downstream module 32 activates arc cost register 33 therein. The contents of activated register 33 are subtracted by one by a clock pulse sent from clock pulse generation circuit 30 through line 29. When the contents of register 33 become zero, flag 3
5 is set. If even one flag 35 in the point module is set, the signal is applied via OR circuit 43 to gate 41, which closes it. gate 41
is closed, the point module no longer accepts clock pulses from line 29. Further, when the flag 35 is set, a signal is transmitted to the arrival detection circuit 38 via the OR circuit 43 at the same time as the gate 37 is opened. If the arrival detection circuit 38 is in the off state,
The signal is used as a trip signal by the OR circuit 45 and the line 28.
an arc module 32 connected further downstream through
propagate to. In this way, the trip signal is delayed and propagated one after another, and the trip signal arrives at the point module corresponding to the destination.

As mentioned above, the arrival detection circuit 38 of this point module
is in the on state. At this point, the trip signal stops and is no longer transmitted downstream. The arrival detection circuit 38 also issues an arrival detection signal, which is transmitted through the line 31 to the control circuit 26 via the input/output device 25. The control circuit 26 stops the clock pulse generation circuit 30. After this, no trip signal propagation occurs. From the above, the shortest time route using the standard arc cost, that is, the main route, connecting the given starting point and destination point has been found. Next, as a second step, the traffic congestion situation on the main route searched above is investigated.

After the above-mentioned shortest time route search process is completed, the input/output device 25
The point code of the destination point is sent to each point module 27A-271 through the line 31. Of the destination point registers 39 of each point module, only those whose point code given by the input signal and the point code stored therein match are turned on. The output signal is transmitted to the gate 37 in each arc module 32 of that point module. Only the gate 37 of these arc modules 32, that is, the gate 37 of the arc module 32 corresponding to the arc on the determined shortest time path, is open, and the output signal passes therethrough and is registered in the register. 36. This causes register 36
The contents of the arc, that is, the code indicating the arc and congestion degree data are read out to the input/output device 25 through the line 31. The signal passing through the gate 37 further propagates through the line 28 to the arc module 32 connected upstream. In this way, reading the contents of the register 36 and propagating the signal are repeated, and when the signal reaches the point module corresponding to the starting point, all the gates 37 there are closed, so it will not propagate any further. The input/output device 25 can detect the shortest route from the departure point to the destination point, that is, the via points of the main route and the traffic congestion situation there, from the contents of the register 36 that are sequentially read out. If a traffic jam point is detected on the main route determined by the processing in the above two steps, the gates 41 of all point modules 27A to 271 are opened again in the same manner as the preparation for the first step.
The gates 37 of all arc modules 32 are closed. Furthermore, the register 35 is reset, and only the arrival detection circuit 38 of one point module corresponding to the destination is turned on and all others are turned off. Then the third
As a step, a route to bypass it is searched.
This third step process searches for a route from the departure point to the destination point in almost the same way as the first step process. However, in this step, the register 34 is used as the arc cost register of each arc module 32. The congestion situation determination device 17 operates as described above, but if a congestion point is not detected in the second step, the route information searched in the first step is used without executing the third step. is sent to the aforementioned receive buffer register 19,
As mentioned above, it is transmitted to the vehicle 3.

Also, if a traffic jam location is detected in the second step,
The third step is executed and the result is sent to the reception buffer register 19. As explained above, according to the present invention, if a congested area is detected on a main route, the driver is informed of the situation. Since most of the determination is done by hardware, the route search and congestion situation determination processes described above can be performed extremely quickly.

[Brief explanation of the drawing]

FIG. 1 is a diagram showing the overall configuration of the present invention, FIG. 2 is a diagram showing a configuration example of the in-vehicle device in the configuration shown in the first diagram, and FIG.
The figure also shows a configuration example of the central processing unit, FIGS.
It is a figure which shows the example of a structure of the point module of the illustrated congestion situation determination apparatus. 1... Point code transmitter, 2...
・Ground antenna, 5 ... Central processing unit, 7
...Antenna, 8, 12 and 14...
・Receiver, 9 ... Departure point code register,
10... Destination point code register, 11 and 20... Transmitter, 13... Transmission device,
15... Receive buffer register, 16...
...Distributor, 17...Congestion situation determination device, 18
...Arc cost setting device, 19...
Transmission buffer register, 21... Voice synthesizer, 25... Input/output device, 26... Control device, 27A to 271... Point module, 3
0... Clock pulse generator, 32...
...Arc module, 33 and 34...Arc cost register, 35...Flag, 36...
...Congestion degree register, 37 and 41...
・Gate, 38... Arrival detection circuit, 39...
... Destination point register, 40 ... Departure point register.

Claims (1)

[Claims] 1. A ground position installed at a predetermined position on a road network, a central processing unit, and an on-vehicle device mounted on a vehicle, and the on-vehicle device is configured to operate when the vehicle passes through the point. means for receiving a ground code uniquely assigned to that point from a ground device at that point and transmitting it to the central processing unit together with a point code of a destination point set in advance in the on-vehicle device by the driver; The central processing unit is configured to receive route guidance information sent from a central processing unit and to notify the driver of the information, and the central processing unit is configured to receive route guidance information sent from a central processing unit and to notify the driver of the information, and the central processing unit is configured to calculate a predetermined travel time between each point in the road network. Based on the point code sent from the in-vehicle device, the shortest route from the passing point to the destination point is determined based on the congestion status data and the congestion status of the route.As a result of the determination, the congestion status of the route is determined. at least one congestion situation determination means that outputs the searched shortest time route if there is no congestion location, and outputs the location and a route that detours around the congestion location if there is a congestion location; means for transmitting the output of the route guidance information to the in-vehicle device, and the congestion situation determining means is connected to correspond to points in the road network and to road sections connecting those points. The point module consists of a plurality of ground modules and an input/output device that sends and receives signals between these ground modules, and each of the point modules has a plurality of arc modules corresponding to a road section whose end is the point. each arc module has a first register that stores the standard travel time required to travel the road section; a second register that stores the actual travel time of the road section; and a second register that stores the actual travel time of the road section. A road traffic flow control method characterized by having a third register for storing congestion status data of a road section, and obtaining the route guidance information in the next step: (1) When the vehicle passes the point A trip signal is generated from the point module (starting point module) corresponding to the point code received at the time, and it is propagated to the downstream arc module,
The arc module that receives the trip signal sequentially propagates the trip signal by delaying the trip signal by the time stored in the first register and then propagating the trip signal to the downstream arc module. , upon arriving at the point module corresponding to the destination point of the point code received from the on-vehicle device, stop the propagation. Next, (2) generate a trip signal from the point module corresponding to the destination point, make this trip signal trace in the opposite direction the arc module through which the trip signal propagated in step (1), and Each time a trip signal reaches the via arc module, the contents of the third register in that arc module are read out to the input/output device and propagated sequentially, and when the trip signal arrives at the starting point module. If so, stop its propagation. (3) If a congested road section is detected in step (2), from the starting point module,
Generate a trip signal again, propagate it to the downstream arc module, and the arc module that receives the trip signal delays the trip signal by the time stored in the second register, and then further The trip signal is sequentially propagated to the arc module on the downstream side, and when it reaches the point module corresponding to the destination point, the propagation is stopped.