JP2001093082A - System for controlling signal adaptive to traffic flow - Google Patents

Abstract

PROBLEM TO BE SOLVED: To smooth the traffic flow in real time according to traffic situation by making common frequency length at all intersections in an area, and optimizing the offset time at each intersection in real time according to traffic situation. SOLUTION: This control system is constituted of plural signals arranged corresponding to plural intersections 4, plural signal controllers 1-n for calculating plural frequency length specific to each of the plural signals 1-n based on vehicle information sensed by plural sensors 3-n arranged corresponding to the plural intersections 4, and a controller 2. In this case, the controller 2 is constituted of a common frequency length calculating mechanism 6 for calculating a common frequency length in an area including the plural signals from the plural frequency length and an offset deciding mechanism 5 for calculating an offset time corresponding to the plural signals based on the vehicle information. Thus, a traffic flow can be controlled from the offset time and the common frequency length. Thus, a proper offset time can be outputted according to unexpected traffic fluctuation, and the traffic flow can be smoothed in a real time according to the traffic situation.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a traffic flow adaptive traffic signal control system and, more particularly, to a traffic flow adaptive traffic signal that optimally controls a traffic flow at a number of intersections included in an object to be controlled by a central controller. Control system.

[0002]

2. Description of the Related Art Such a traffic signal control method, in which a plurality of traffic signal controllers are respectively provided at a plurality of intersections to control traffic flow, is controlled by a "table" which is controlled according to a predesigned display plan. Type signal control method "and" traffic flow-adaptive signal control method "which performs optimal signal control according to the traffic flow that changes every moment.

FIG. 10 shows a table type signal control method. The table-type signal controller 102 provided at the intersection 101 performs signal control according to a time table 103 in which offset times are determined corresponding to a plurality of patterns. FIG. 11 shows a traffic flow adaptive signal control method. In the traffic flow adaptive signal control method, a traffic flow adaptive signal controller 105-n provided at each of a plurality of intersections 104-n includes a sensor 106-n provided at each intersection 104-n. The number of detected vehicles and the average speed are input from the
A central control device 108 including a common cycle length calculating mechanism 107 for calculating a common cycle length from the number of inflows calculated by n and the optimum cycle length is provided. The central controller 108 further includes an offset time table 109, determines parameters for performing the system control from the offset time and the calculated common cycle length, and determines a plurality of intersection points 104-1 and 104-1.
System control is performed in the control target area including n.

The table-type signal control method operates in accordance with given signal control parameters such as a cycle length, a split and an offset time, and when system control is performed, the cycle length of the table-type signal controller 102 belonging to the area is controlled. There is no need to make common and adjust the offset time. Here, the split means a time ratio of each signal display in one signal cycle. Offset time is a display that shifts the display such as blue display at successive intersections for each intersection in order to smooth traffic flow when performing signal control in an area including multiple intersections. Start time. System control refers to performing such offset time control within an area. For such system control, it is necessary to unify the cycle length of each traffic light.

The table-type signal control method in which an offset time table is prepared for each traffic signal requires a great deal of labor for the preparation, and it is difficult to provide an optimal offset time following unexpected traffic fluctuation. It is. Known traffic flow-adaptive system control executed in accordance with an offset time table created based on empirical rules is actually control based on prediction, and cannot be said to be a traffic flow-adaptive system.

It is desired that the commonization of the cycle length at all the intersections in the area and the optimization of the offset time at each intersection are performed in real time according to the traffic conditions. Furthermore, it is desired that the traffic signal at each intersection determines the optimum cycle length and split for each cycle depending on the traffic flow.

[0007]

SUMMARY OF THE INVENTION An object of the present invention is to provide a traffic flow adaptive traffic light control system capable of smoothing a traffic flow in real time according to a traffic situation. Another object of the present invention is to achieve a common traffic length at all crossing points in an area and to optimize an offset time at each crossing point in real time in accordance with the traffic situation. It is an object of the present invention to provide a traffic flow adaptive type traffic signal control system capable of smoothing a traffic flow in real time according to the traffic flow.

[0008]

Means for solving the problem are described as follows. The technical items appearing in the expression are appended with numbers, symbols, and the like in parentheses (). The numbers, symbols, and the like are technical items that constitute at least one embodiment or a plurality of the embodiments of the present invention, in particular, the embodiments or the examples. Corresponds to the reference numerals, reference symbols, and the like assigned to the technical matters expressed in the drawings corresponding to the above. Such reference numbers and reference symbols clarify the correspondence and bridging between the technical matters described in the claims and the technical matters of the embodiments or examples. Such correspondence / bridge does not mean that the technical matters described in the claims are interpreted as being limited to the technical matters of the embodiments or the examples.

A traffic flow adaptive traffic light control system according to the present invention comprises a plurality of traffic lights arranged at a plurality of intersections (4) and a plurality of sensing lights arranged at a plurality of intersections (4). (3-n) and a plurality of signal controllers (1) for calculating a plurality of cycle lengths unique to the plurality of traffic signals (1-n) based on vehicle information sensed by the sensor (3-n).
-N) and a control device (2).
Is a common cycle length calculation mechanism (6) for calculating a common cycle length in an area including a plurality of traffic signals from the plurality of cycle lengths, and an offset determination mechanism (calculation) for calculating an offset time corresponding to the plurality of traffic signals based on vehicle information. 5). The traffic flow is controlled from the offset time and the common cycle length. According to such a calculation, there is no need to create an offset timing table, and it is possible to output an appropriate offset time by following an unexpected traffic change,
According to traffic conditions, traffic flow can be smoothed in real time.

The vehicle information includes the number of vehicles flowing into each intersection (4), the number of vehicles flowing out from each other intersection (4), and the two intersections (4, 4). ) And the average speed of a plurality of vehicles passing between them. The multiple controllers (1) can calculate a split unique to the multiple traffic signals based on the vehicle information.

The offset determining mechanism (5) includes a queue number estimating mechanism (11) and a queue clearing time calculating mechanism (1).
2) and an offset time determining mechanism (14), and the queue number estimating mechanism (11) includes a sensor arranged at the intersection upstream and a sensor arranged at the downstream of the intersection. The number of queues in the current cycle is estimated from the number of outflows obtained from the vessel and the number of queues estimated in the previous cycle. The queue clearance time calculation mechanism (12) calculates a queue clearance time required for the last vehicle in the queue to pass through the intersection based on the current number of queues. The offset time (T1) can be calculated by the offset time determining mechanism taking into account the queue cleanup time (t).
In the control method in which the offset time determination mechanism (14) only calculates the offset time T1 by estimating the travel time between the intersections from the average speed and the intersection distance, if the number of intersection queues increases, the calculated offset time is increased. In some cases, the time T1 is not appropriate, but the occurrence of the inappropriateness is determined by the queue number estimation mechanism (1) for calculating the offset time T1.
This can be prevented by incorporating the estimation of the number of queues according to 1) and the queue clearance time t by the queue clearance time calculation mechanism (12).

A table (13) can be used to calculate the matrix clearance time. In the table (13), it is preferable that when the number of rows and columns is small, a fixed value is designated according to the number, and when the number of rows and columns is large, it is preferable that a value is designated by a linear function corresponding to the number. The number of queues is estimated by an estimation formula: current number of queues = number of queues in the previous cycle + number of inflows−number of outflows. The offset time T1 is calculated by the following equation: T1 = intersection travel time + queue vehicle cleaning time.

The offset determination mechanism (5) further includes a system synchronization point adjustment mechanism (15), and the system synchronization point adjustment mechanism (15) includes a queue clearing time calculation mechanism (12) and an offset time determination mechanism (14). ). The system synchronization point adjustment mechanism (15) determines an intersection (4) to be synchronized and a synchronization timing in a wider systematic route, and the intersection (4) and the timing to be synchronized are offset times. It is input to the decision mechanism (14).

The system synchronization point adjustment mechanism (15) includes a route map (16) of the entire area to be controlled and a synchronization point inversion mechanism (1).
7), the information on the systematic route is input to the synchronization point reversing mechanism (17), and the route map information is further converted into the route map (1).
6) is input to the synchronization point reversal mechanism (17), and the synchronization point reversal mechanism (17) determines whether or not to include a right / left turn at the intersection to be systematized based on the route map information and the information on the systematic route. Is determined and the synchronization point is adjusted. Adjustment of the synchronization point allows control including turning right and left at an intersection that is systematized on a route that is widened.

Further, an offset time database (1)
8) and an offset time table (19). An offset time determining mechanism (14) is connected to the offset time database (18), and the offset time determining mechanism (1) is connected to the offset time database (18).
4) The offset time calculated in each cycle, the number of vehicles passing and the number of queues detected by the sensor continue to be accumulated, and the offset time table (19) is based on the data accumulated in the offset time database (18). Created automatically. Control of the traffic flow by the offset time table is possible as before, but such a table can be created automatically.

[0016]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS In accordance with the drawings, a traffic flow adaptive signal control system according to the present invention is provided with a plurality of traffic flow adaptive signal controllers connected to a central controller. The plurality of traffic flow compatible signal controllers 1-1,.
., N (hereinafter, 1 is used as a representative) are connected to the central controller 2 respectively. Each traffic flow adaptation type signal controller 1 has sensors 3-1,.
Are used as representatives).

The sensor 3 includes a plurality of intersection points 4-1,.
, N (hereinafter, 4 is used as a representative). The sensors 3 are provided as three types of sensors between the intersection 4-2 and the intersection 4-3, as shown in FIG. 2 according to an example. The detector 3-2A is connected at the intersection point 4-
2 and the detector 3-3B is located at the intersection 4-3.
The sensor 3-2C is disposed between the inflow side at the intersection 4-2 and the outflow side at the intersection 4-3.

Each sensor 3 counts the number of inflow vehicles passing on its inflow side, counts the number of outflow vehicles passing on its outflow side, and calculates the average speed of those passing vehicles at an intermediate position. It is preferable that each traffic flow compatible signal controller 1 calculates an optimum cycle length and a split unique to the traffic signal based on the number of passing vehicles measured by the sensor 3 at the intersection. The number of passing vehicles and the optimum cycle length are transmitted to the central control device 2 which controls all the intersections 4-1 and n in the area to be controlled.

The central controller 2 has an offset determining mechanism 5
And a common cycle length calculation mechanism 6. Each inflow number, each outflow number, and each average speed are input to the offset determination mechanism 5. Each inflow number and each optimum cycle length are input to the common cycle length calculation mechanism 6. The offset determination mechanism 5 includes:
The selected systematic route and control mode are input. The offset determination mechanism 5 calculates an offset time T1 unique to each intersection based on the number of detected vehicles, the average speed, the systematic route, and the control mode. The common cycle length calculation mechanism 6
The common cycle length T2 is calculated based on the number of inflows and the optimum cycle length. Each offset time T1 and common cycle length T2 are
It is transmitted to each traffic flow adaptive signal controller 1.

FIG. 3 shows details of a circuit block in which the offset determining mechanism 5 of the central control unit 2 determines the offset time T1 by calculation. Offset determination mechanism 5
Has a mode selection mechanism 7. Mode selection mechanism 7
, The number of inflows, the number of outflows, and the average speed are input. The mode selection mechanism 7 selects one of two modes. The two modes are a central control control mode 8 and an automatic output mode 9. The central control mode 8 is a mode in which system control is performed by all the traffic flow adaptive signal controllers 1 in the area in accordance with the offset time table given to the central control device 2. The automatic output mode 9 is a mode in which the central control device 2 calculates and outputs the offset time T1.
Whichever mode is selected, the route to be systemized and the operation mode are input to the mode selection mechanism 7.

When the automatic output mode 9 is selected, the queue number estimation mechanism 11 operates. The number-of-queues estimation mechanism 11 calculates the number of inflows obtained from the sensors 3-2A disposed upstream of the intersection, the number of outflows obtained from sensors 3-2B disposed downstream of the intersection, The number of queues in the current cycle is estimated from the number of queues estimated in (1). For the estimation of the number of queues, an image-type queue measuring instrument may be used, but in the present embodiment, the following estimation formula is used: Current number of queues = Number of queues in the previous cycle + Number of inflows-Outflow Number.

In the automatic output mode 9, the queue number estimating mechanism 11 is connected to the queue clearing time calculating mechanism 12. The queue clearance time calculation mechanism 12 calculates a queue clearance time t required for the last vehicle in the queue to pass the intersection based on the current number of queues. The table 13 shown in FIG. 4 can be used for the calculation. If the number of rows and columns is 1 and 2, as t, values 2.5 and 5.5 shown in the upper two rows of table 13 are used, respectively. If the number of queues x is 3 or more,
t = 2x + 1.5.

The queue clearing time calculating mechanism 12 is connected to the offset time determining mechanism 14. The offset time determination mechanism 14 calculates and outputs the offset time of the downstream intersection with respect to the upstream intersection of the systematic route from the queue clearance time t, the average speed of the vehicle, and the distance between the intersections.
In the central control mode 8, the offset time is input, and each traffic flow adaptive signal controller 1 executes system control according to the offset time table.

The real-time calculation of the offset time T1 transmitted to the traffic flow adaptive signal controller 1 arranged at each intersection can eliminate the effort of creating the offset timing table and was unexpected. An appropriate offset time can be output following the traffic fluctuation. Such an offset time T1 can be estimated by the following equation. T1 = intersection travel time + queue vehicle cleaning time t

In the control method in which the offset time determination mechanism 14 only calculates the offset time T1 by estimating the travel time between the intersections from the average speed and the intersection distance, the offset time T1 is calculated if the number of intersection queues increases. Offset time T1
May not be appropriate, but the occurrence of
The calculation of the offset time T1 is prevented by incorporating the estimation of the number of queues by the queue number estimating mechanism 11 and the queue cleaning time t by the queue cleaning time calculating mechanism 12.

By appropriately using the two general control modes, an appropriate offset time T1 is determined according to traffic conditions such as depopulation and supersaturation, and the appropriate offset time T1 is determined by each traffic flow adaptive signal controller. 1 can be provided. The automatic output mode 9 is a mode suitable for depopulation and normal times. At the time of supersaturation, it is necessary to take into account not only the offset theory of the vehicle in which direction to flow but also the traffic policy of the entire area at which intersection to prevent the inflow of the vehicle. The offset time is not always appropriate. In such a case, the central control mode 8 is provided as an environment for utilizing the rule of thumb.

FIG. 5 shows another embodiment of the traffic flow adaptive traffic light control system according to the present invention. This embodiment differs from the embodiment shown in FIG. 3 only in that a system synchronization point adjustment mechanism is added. In the automatic output mode 9, the system synchronization point adjusting mechanism 15 includes a queue clearing time calculating mechanism 12 and an offset time determining mechanism 14.
It is interposed between and. The system synchronization point adjustment mechanism 15
When a plurality of systematic routes are input, the input information is interpreted, the intersections to be synchronized and their appropriate timings are determined, and these are output to the offset time determination mechanism 14.

FIG. 6 shows a mode of operation of the system synchronization point adjusting mechanism 15. The system synchronization point adjustment mechanism 15 includes a route map 16 of the entire area to be controlled and a synchronization point inversion mechanism 17. The systematic route information is input to the synchronization point inversion mechanism 17. Further, the route map information is input from the route map 16 to the synchronization point reversing mechanism 17. The synchronization point reversing mechanism 17 determines whether or not the systemized intersection includes a right / left turn based on the route map information and the systematic route information, and adjusts the synchronization point.

Such system control is realized by synchronizing at the end of the green display of the signal controller on the systematic route. FIGS. 7 and 8 show the synchronization point adjustment by such system control. Intersection point 4-A shown in FIGS. 7 and 8
The east-west direction is called the main direction, and the north-south direction is called the subordinate direction. When the system control is performed on the route A in FIG. 7, it is necessary to synchronize at the intersection 4-B with the end point of the blue presentation in the main direction of the intersection 4-A. Routes B and C in FIG.
When the system control is performed at the intersection point 4-B, it is necessary to synchronize with the intersection point 4-A at the end of the blue presentation in the slave direction (end point of the red presentation in the main direction).

As described above, depending on how the systematic route is selected,
Even at the same crossing point, the timing of synchronization is different.
The offset determination mechanism 5 determines the crossing point to be synchronized by the system synchronization point adjustment mechanism 15 and the synchronization timing based on the route map of the area and the input information on the systematic route. By incorporating such a mechanism, it is possible to determine an offset time when performing system control on a route including a right / left turn at an intersection.

FIG. 9 shows still another embodiment of the control system for a traffic flow adaptive traffic signal according to the present invention. This embodiment is different from the embodiment shown in FIG.
The only difference is that an offset time database 18 to which the offset time determination mechanism 14 connects is added. The offset time table 19 is included in the central control mode 8 as before (that is, the same as the central control mode 8 in FIG. 3 has it). However, the offset time database 18 is connected to the offset time table 19.

The offset time calculated by the offset time determining mechanism 14 in each cycle and the number of vehicles passing and the number of queues measured by the sensor 3 in each cycle are continuously stored in the offset time database 18. An offset time table 19 is created based on the accumulated data. In this way, an automatic offset time table generation mechanism can be added to the embodiment shown in FIG. The offset time table of the conventional central control device that determines the offset time has been created based on the empirical rules of the operator and the traffic volume survey, but the offset time database 18 is incorporated to accumulate the calculated offset times. The offset determining mechanism 5 according to the present invention investigates and analyzes the relationship between the day of the week, the time, and the traffic volume and time, and can automatically generate an offset time table using a conventional table.

[0033]

The traffic flow adaptive traffic signal control system according to the present invention can smooth the traffic flow in real time according to the traffic situation. Furthermore, since the common cycle length at all intersections in the area and the optimization of the offset time at each intersection are performed in real time according to the traffic conditions, the traffic can be changed in real time according to the traffic conditions. The flow can be smoothed.

[Brief description of the drawings]

FIG. 1 is a system configuration diagram showing an embodiment of a traffic flow adaptive signal control system according to the present invention.

FIG. 2 is an axial projection showing the arrangement of sensors on a certain route.

FIG. 3 is a circuit block diagram illustrating an embodiment of an offset determining mechanism.

FIG. 4 is a time table showing a vehicle passage time;

FIG. 5 is a circuit block diagram showing another embodiment of the offset determining mechanism.

FIG. 6 is a circuit block diagram illustrating an embodiment of a system synchronization point adjustment mechanism.

FIG. 7 is a circuit block diagram illustrating an embodiment of a synchronization point adjustment method.

FIG. 8 is a circuit block diagram showing another embodiment of the synchronization point adjusting method.

FIG. 9 is a circuit block diagram showing still another embodiment of the traffic flow adaptive signal control system according to the present invention.

FIG. 10 is a table showing a known table-type signal control method.

FIG. 11 is a system block diagram showing a known traffic flow adaptive signal control method.

[Explanation of symbols]

 1-n: Multiple traffic lights 2 ... Control device 4 ... Multiple intersection points 3-n ... Multiple sensors 5 ... Offset determination mechanism 6 ... Common cycle length calculation mechanism 11 ... Queue number estimation mechanism 12 ... Queue clearing time calculation mechanism 13 ... Table 14 ... Offset time determination mechanism 15 ... System synchronization point adjustment mechanism 16 ... Route map 17 ... Synchronization point inversion mechanism 18 ... Offset time database 19 ... Offset time table T1 ... Offset time t ... Queue clearing time

 ────────────────────────────────────────────────── ─── Continuing on the front page (72) Inventor Shigetatsu Katayama 1-1-1 Wadazakicho, Hyogo-ku, Kobe City, Hyogo Prefecture F-term in Mitsubishi Heavy Industries, Ltd. Kobe Shipyard 5F180 AA01 DD02 JJ02 JJ02 JJ06 JJ12

Claims (10)

[Claims] A plurality of traffic lights arranged corresponding to a plurality of intersections; a plurality of sensors arranged corresponding to the plurality of intersections; and a vehicle information detected by the plurality of sensors. A plurality of signal controllers for calculating a plurality of cycle lengths which are unique to each of the plurality of traffic signals; and a control device, wherein the control device calculates a common cycle length in an area including the plurality of traffic signals from the plurality of cycle lengths. A traffic flow adaptive traffic signal control system, comprising: a common cycle length calculation mechanism; and an offset determination mechanism that calculates an offset time corresponding to the plurality of traffic signals based on the vehicle information. 2. The vehicle information according to claim 1, wherein the vehicle information includes the number of vehicles flowing into each of the intersections, the number of vehicles flowing out of each of the intersections,
A traffic flow adaptive traffic light control system formed from an average speed of a plurality of vehicles passing between two intersections. 3. The traffic flow adaptive traffic signal control system according to claim 2, wherein the plurality of controllers calculate a split unique to the plurality of traffic signals based on the vehicle information. 4. An apparatus according to claim 2, wherein said offset determining mechanism comprises: a queue number estimating mechanism; a queue clearing time calculating mechanism; and an offset time determining mechanism. Estimate the number of queues in the current cycle from the number of inflows obtained from the sensors arranged at the intersection, the number of outflows obtained from the sensors arranged downstream of the intersection, and the number of queues estimated in the previous cycle. The queue clearing time calculation mechanism calculates a queue clearing time required for the last vehicle in the queue to pass the intersection based on the current number of queues, and the offset time is the queue clearing time. The traffic flow adaptive traffic signal control system calculated by the offset time determining mechanism in consideration of the following. 5. The system according to claim 4, wherein a table is used to calculate the matrix cleanup time. In the table, when the number of rows and columns is small, a constant value is designated according to the number of rows and columns, and the number of rows and columns is specified. A traffic flow adaptive traffic signal control system whose value is specified by a linear function corresponding to the number when the number is large. 6. The traffic flow adaptive traffic signal according to claim 4, wherein the number of queues is estimated by the following equation: Current number of queues = Number of queues in previous period + Number of inflows−Number of outflows. Control system. 7. The traffic flow adaptive traffic signal control system according to claim 6, wherein the offset time T1 is calculated by the following equation: T1 = intersection travel time + queuing vehicle clearing time. 8. The system according to claim 4, wherein said offset determining mechanism further comprises a system synchronization point adjusting mechanism, wherein said system synchronization point adjusting mechanism is configured to control a communication between said queue clearing time calculating mechanism and said offset time determining mechanism. The system synchronization point adjustment mechanism determines an intersection point to be synchronized and a timing of the synchronization in a wider systematic route, and the intersection point to be synchronized and the timing are offset by the offset. Traffic flow adaptive traffic signal control system input to the time decision mechanism. 9. The system synchronization point adjustment mechanism according to claim 8, wherein the system synchronization point adjustment mechanism comprises a route map of the entire area to be controlled and a synchronization point inversion mechanism, and information on the systematic route is input to the synchronization point inversion mechanism. Further, route map information is input to the synchronization point reversing mechanism from the route map, and the synchronization point reversing mechanism, based on the route map information and the information on the systematic route, the intersections to be systematized A traffic flow adaptive traffic signal control system that determines whether a turn is included or not and adjusts the synchronization point. 10. The offset time database according to claim 1, further comprising: an offset time database; and an offset time table, wherein the offset time determination mechanism is connected to the offset time database, and the offset time determination mechanism is connected to the offset time database. Continues to accumulate the offset time calculated in each cycle, the number of vehicles passing and the number of queues detected by the sensor, and the offset time table is automatically created based on the data stored in the offset time database. Adaptive signal control system.