JP2000011290A - Method and device for estimating travel time and congestion information - Google Patents

Abstract

PROBLEM TO BE SOLVED: To generate and update a correction coefficient DB for estimating travel time and congestion information easily with high precision by providing a function which automatically generates a correction coefficient by making use of measurement information from an on-vehicle machine. SOLUTION: A traffic information estimating device 16 consists of a travel time estimation part 160, a congestion information estimation part 161, and a map DB 162. The travel time and congestion information are estimated in real time (normally at intervals of five minutes) by utilizing a map data base of the map DB 162, information from a beacon 11, an AVI system 12 or a vehicle sensor 13 received through an information communication part 14, or a data base of the correction coefficient DB 15. The estimation result is sent to an on-vehicle machine mounted vehicle 10 through the information communication part 14 and beacon 11. Furthermore, the correction coefficient DB 15 is a data base used by a travel time estimation part 160 of the traffic information estimating device 16 and updated when a new data base is generated by a correction coefficient generation part 171.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method and an apparatus for estimating a travel time of a target section in road traffic and an application system thereof.

[0002]

2. Description of the Related Art As a conventional technique for estimating travel time and congestion information of a target section in road traffic, traffic data from various vehicle detectors 20 on a road is aggregated via a modem 21 as shown in FIG. The traffic data from at least one vehicle sensor is used to determine the travel time of the target section. The correction coefficient DB23 is a correction database, the map DB25 is a geographic database such as the distance of the target section,
The travel time estimating unit 22 estimates the current travel time using the traffic data and the traffic data, and the map DB 25 and the traffic jam information estimating unit 24 uses the traffic data or the estimated travel time to determine the degree of traffic and the length of the traffic. There is a travel time / congestion information estimation method for estimating congestion information such as traffic information.

In this method, the following steps are required to create the correction coefficient DB 23. (1) The vehicle actually travels in the target section and travel time data in each time zone is recorded.

[0004] (2) Traffic data (point speed data) at the same time as the travel time in (1) obtained from a vehicle sensor near the target section is output.

(3) Based on the data of (1) and (2) and the distance of the target section, the skilled person can adjust the speed from the vehicle detector according to the following equation so as to match the actually measured travel time T of (1). Data V
Are adjusted.

[0006]

T (t) = L / {α (1) · V1 (t) + α (2) · V2 (t) +... + Α (n) · Vn (t)} + β (Equation 1) Here, t is time, L is the distance of the target section, α is a real number greater than or equal to 0 (no unit), β is a real number (unit is seconds), and n is the number of vehicle sensors used for travel time estimation. In mathematical terms, α is a coefficient for correcting the speed V from the vehicle detector, and β is a parameter for expressing a delay time or the like at an intersection signal that cannot be expressed by the speed correction coefficient α alone.

[0007]

In the prior art described above, since there are important steps such as adjustment of coefficients relating to estimation accuracy in the creation of the correction coefficient DB 23, a skilled person is required and an actual driving survey is required. Therefore, it takes a very large number of steps to create the correction coefficient DB 23 for the entire road network.

Further, basically, the travel time is estimated based on the traffic data from the vehicle detector without changing the correction coefficient DB 23, so that the road condition changes due to seasons such as snowfall, the road network changes due to road construction, etc. In order to cope with this, the steps (1) to (3) in the above-described prior art had to be redone, so that it was practically difficult to update the correction coefficient DB 23 every time the road conditions changed.

Therefore, an object of the present invention is to provide a function for automatically creating a correction coefficient by using measurement information from an on-vehicle device, so that actual driving surveys and a lot of work by skilled persons are required. In addition, it is possible to create and update a correction coefficient DB for easily and highly accurately estimating travel time and congestion information, and to adapt to changes in traffic conditions by updating the correction coefficient DB effectively.・
It is an object of the present invention to provide a method and an apparatus for estimating congestion information and a storage medium storing a program for executing the method.

Another object of the present invention is to provide traffic information such as estimated travel time or traffic information output by the travel time / congestion information estimation device to a driver without a dedicated vehicle-mounted device. It is to provide a traffic information providing system.

Another object of the present invention is to use traffic information such as estimated travel time or congestion information output by the travel time / congestion information estimating device as input data in a signal control device, thereby reducing traffic conditions. It is an object of the present invention to provide a traffic signal control system that dynamically controls a traffic signal in response.

[0012]

SUMMARY OF THE INVENTION The object of the present invention is to provide a method for estimating travel time or traffic congestion information of a target section by using a correction database for correcting the vehicle sensor data. The actual travel time data and the vehicle sensor data obtained at that time are stored in pairs, a correction database is created or updated based on the stored data, and a target section is created using the correction database and the vehicle sensor data. This is achieved by a travel time / congestion information estimation method for estimating travel time or traffic information.

The travel time / congestion information estimating apparatus for achieving the above object is a data storage means for storing a pair of measured travel time data obtained from a beacon on the road and vehicle sensor data at that time, Correction data creating means for creating or updating a correction database based on
Traffic information estimating means for estimating travel time or congestion information of the target section using the correction database.

Another feature of the travel time / congestion information estimating apparatus is that the data stored in the data storage means includes at least one of a predefined section number and a passing time of a start point or an end point of the section. On the other hand, the speed data obtained by the sensor used for estimating the travel time and the actually measured travel time of the section.

Another feature of the travel time / congestion information estimation device is that the data stored in the data storage means is an abnormal value based on comparison with past statistical data or a predetermined threshold value. Is determined, and if there is at least one abnormal value among the stored data collected in one target section, the corresponding stored data of the corresponding section is deleted from the data storage unit, thereby saving the stored data. To improve quality.

Another feature of the travel time / congestion information estimating apparatus is that the correction data creating means minimizes the evaluation function of the target section by using a square error between the actually measured travel time and the estimated travel time. Such correction data is required.

Another feature of the travel time / congestion information estimating device is that the correction data creating means converts the evaluation function of the target section into a square error between the measured travel time and the estimated travel time and an index representing the variation of the correction data. The purpose is to obtain correction data that minimizes the evaluation function.

Another feature of the travel time / congestion information estimating apparatus is that the correction data creation means compares the number of actually measured travel time data of the target section stored in the data storage means with a predetermined value. , To determine whether to newly create correction data for the section.

Another feature of the travel time / congestion information estimating apparatus is that, in the creating means, the data to be used out of all the stored data stored in the data storing means is provided by a man-machine for a desired period of time. It is about choosing data.

Another feature of the travel time / congestion information estimating apparatus is that the correction data generating means determines a past time period as a data to be used among all the stored data stored in the data storing means. Is to sort out the data.

Another feature of the travel time / congestion information estimating apparatus is that, in the correction data creating means, there is a difference in traffic patterns as data to be used among all the saved data saved in the data saving means. It's about choosing data when it comes out.

Another feature of the travel time / congestion information estimating apparatus is that the correction data generating means determines whether the original correction database is used by the traffic information estimating means to newly generate the correction data. It is to determine whether or not to update the corrected correction database.

Another feature of the travel time / congestion information estimating apparatus is that the original correction database is temporarily copied to another storage medium by the correction data creating means, and the newly created correction database is used as traffic information estimating means. Updates the correction database that was copied at a time when the original correction database was not used, to the newly created correction database, and then uses the updated correction database on another storage medium for the original correction database The replacement of the original correction database at the next timing that has not been performed.

Another feature of the travel time / congestion information estimating apparatus is that the correction data generating means compares the calendar time of the computer with a predetermined date and time to determine whether to newly generate a correction database. Is to make the judgment automatically.

Further, another feature of the travel time / congestion information estimating device is that a traffic information estimating means in the travel time / congestion information estimating device, and an information providing board on a road which is connected to the traffic information estimating unit online. Or an information providing device such as an FM multiplex broadcasting station, and provides a travel time information to a driver via the information providing device.

Further, another feature of the travel time / congestion information estimating apparatus is that traffic information estimating means in the travel time / congestion information estimating apparatus and travel time or traffic congestion information estimated by the traffic information estimating means are used. The traffic signal control system includes a signal control device for obtaining a signal parameter based on the traffic signal and an intersection traffic light connected online with the signal control device, and realizes smooth traffic flow.

[0027]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Next, an embodiment of a travel time / congestion information estimation method and apparatus of the present invention and a traffic information providing system to which the invention is applied will be described with reference to the drawings.

FIG. 1 is a block diagram showing an embodiment of a traffic information providing system including a travel time / congestion information estimating apparatus according to the present invention. The travel time / congestion information estimating device includes a traffic information estimating device, a correction coefficient DB, and a correction coefficient creating device. That is, the system according to the present embodiment includes a traffic information estimating device according to the present invention, a correction coefficient DB
And a correction coefficient creating device, an information communication unit, a beacon,
It is composed of road sensors.

The processing flow of the present invention and the function of each unit constituting the present invention will be described below with reference to FIG.

In FIG. 1, reference numeral 10 denotes a vehicle traveling on the road, which is equipped with a vehicle-mounted device having a function of transmitting (uplinking) the traveling information of the vehicle to the beacon 11. The in-vehicle device may have a function of receiving various traffic information such as regulation information, traffic congestion information, or travel time information from the beacon 11 in some cases.

Reference numeral 11 denotes a beacon, which has a function of receiving travel information from the on-vehicle device 10 and transmitting the information to the information communication unit 14, for example, transmitting information to the information communication unit 14 such as a radio transmitter. It can be replaced by any device that can. The beacon may have a function of transmitting (downlink) the traffic information transmitted through the information communication unit 14 to the vehicle-mounted device 10.

Reference numeral 12 denotes an AVI system, which automatically recognizes a license plate photographed by a TV camera by image processing and records the license plate together with the passing time of the vehicle. The difference between the passing times when the numbers recognized at the two points match each other. Is output as travel time. Also, AVI
The system 12 has a function of transmitting the travel time information to the information communication unit 14.

Numeral 13 denotes a vehicle detector for detecting a passing vehicle. The vehicle detector detects an amount of traffic per unit time, such as an ultrasonic sensor, an R-type sensor, a loop coil sensor, an image sensor, or an optical sensor. It can be replaced by any sensor that can measure sensor data such as time occupancy or vehicle speed. The vehicle sensor 13 has a function of transmitting the measured sensor data to the information communication unit 14.

The information communication unit 14 receives information from the AVI system 12 or the vehicle detector 13 on the road, and transmits the information to the travel time estimation unit 160 and the traffic congestion information estimation unit 161 of the traffic information estimation device 16. Conversely, it has a function of receiving each output information and distributing the output information to the beacon 11. The information communication unit 14 also has a function of transmitting travel data from the beacon 11 on the road and sensor data from the vehicle sensor 13 to the data storage unit 170 of the correction coefficient creation device 17.

The correction coefficient DB 15 stores the traffic information estimation device 1
6 is a database for use in the travel time estimating section 160, and is updated when a new database is created by the correction coefficient creating section 171 of the correction coefficient creating apparatus 17.

FIG. 3 shows an example of the correction coefficient DB. In FIG. 3, section No. is a section number of a section for which travel time is to be estimated, and a legal speed for each section is set. Further, four coefficients and one bias are set. Coefficient and bi
“as” corresponds to α and β on the right side of the travel time calculation formula of Equation 1, respectively. In the example of FIG. 3, the maximum number of vehicle sensors used for travel time estimation is four. Therefore,
In the section where the coefficient is 0 in FIG. 3, it indicates that the number of sensors used for travel time estimation is less than four. Further, as the coefficient and bias, for example, several sets of values corresponding to a time zone (during a traffic rush / during a busy day) or a season may be prepared and used properly.

The traffic information estimating device 16 is composed of a travel time estimating unit 160, a traffic congestion information estimating unit 161, and a map DB 162. The beacon 11, A on the road received through the information communication unit 14 and the map database of the map DB 162.
A function of estimating travel time and congestion information in real time (normally every 5 minutes) using information from the VI system 12 or the vehicle sensor 13 or a database of the correction coefficient DB 15 is provided. It also has a function of transmitting to the vehicle-mounted device 10 through the information communication unit 14 and the beacon 11.

Next, a detailed function of each unit constituting the traffic information estimating apparatus 16 will be described.

The travel time estimating section 160 stores the map DB 162
, The information from the road beacon 11, the AVI system 12, or the vehicle detector 13 received through the information communication unit 14, and the database of the correction coefficient DB 15, The travel time of the vehicle 10 is estimated in real time, and the estimation result is transmitted through the information communication unit 14 and the beacon 11 to the vehicle-mounted vehicle 10.
To send to.

The traffic congestion information estimating unit 161 stores the map DB 162
Using the map database and information from the roadside beacon 11, the AVI system 12, or the vehicle sensor 13 received through the information communication unit 14, traffic congestion information such as the degree of congestion and the length of congestion are estimated and estimated. The result is to be transmitted to the vehicle-mounted device 10 via the information communication unit 14 and the beacon 11.

As an example for estimating the degree D of congestion, an example in which a congestion index I indicating an index of the degree of congestion is used will be described with reference to FIGS.

First, the congestion index I is obtained by the function f (V) determined in FIG. 4 according to the speed data V obtained directly by the vehicle sensor 13 or obtained indirectly by the estimation formula. Next, the degree of congestion D is determined by the function g (I) determined in FIG. 5 according to the determined congestion index I. Here, 0 of the degree of congestion is unknown (at the time of error), 1 is normal, 2 is congestion, and 3 is congestion. When a plurality of vehicle sensors are installed in one section, a plurality of traffic congestion indices I and a plurality of traffic congestion degrees D are calculated. In this case, the traffic congestion indices I are averaged first, and the traffic congestion index I is calculated. The congestion degree D is calculated by g (I) based on the index average value.

There is a method of estimating the congestion length in accordance with the position of the vehicle sensor from which the congestion degree D is obtained.

A specific example will be described with reference to FIG.

In FIG. 6, S1 and S2 indicate vehicle sensors, and distances from the nearest upstream intersection are L1 and L, respectively.
2 is shown. The congestion length is determined, for example, as shown in FIG. 7 by the combination of the congestion degrees of the two vehicle sensors. Here, since the traffic congestion degree 2 and the traffic congestion degree 3 are treated as being equal, the combination shown in FIG. 7 is used. That is, the maximum value of the distance from the upstream intersection of the vehicle sensor whose degree of congestion is 2 or more is used as the congestion length. Here, the head of the congestion is the upstream intersection.

As another method for estimating the length of traffic jam,
There is a method of using the estimated travel time information described above without using the information of the vehicle detector. In this method, an average travel speed is obtained from the estimated travel time and the distance of the corresponding section, a traffic jam index I is obtained from the function f (V) of FIG. 4 based on the average travel speed, and a traffic jam length Lj is obtained by the following equation, for example. .

[0047]

Lj = LI (when I> I1) (Equation 2) Here, L is the section length. However, when I ≦ I1, the traffic jam length Lc is zero. The map DB 162 is a database relating to a map that defines sections and the like. Specifically, the map DB 162 is used for a road map such as an arrangement of links, which is a minimum unit of section, a section length, the number of lanes, or an installation position of a roadside device such as a vehicle sensor. It contains necessary attribute data. Map DB 162
Is a basic database necessary for the travel time estimating unit 160 and the traffic congestion information estimating unit 161 to estimate the travel time and the traffic congestion information of the target section, respectively. Correction coefficient creation device 17
Is composed of a data storage unit 170, a correction coefficient creation unit 171, and a map DB 172, and collects and stores the measured travel time and vehicle sensor information transmitted from the beacon 11 and the vehicle sensor 13 through the information communication unit 14, A correction coefficient for estimating the travel time from the vehicle sensor information using the actually measured travel time data as teacher data is to be obtained.

Next, a detailed function of each section constituting the correction coefficient creating device 17 will be described.

The data storage unit 170 includes the correction coefficient creation unit 1
The measured travel time and the vehicle sensor information transmitted from the beacon 11 and the vehicle sensor 13 through the information communication unit 14 are collected and stored for use at 71.

FIG. 8 shows an example of the stored information.

In FIG. 8, the section No. is stored in the map DB in advance.
172, the vehicle ID is an ID number assigned to each in-vehicle device, and the time when each vehicle passed through the start point and the end point of the section is the departure time and the arrival time, respectively. The speeds 1 to 4 are average speed data per unit time from the departure time to the arrival time of each vehicle sensor. Here, the fact that the speed data is 0 means that there is no vehicle sensor in the section or the vehicle sensor data is not used.

In general, the vehicle sensor data usually measures two types of traffic volume Q and occupancy Ot per unit time. From these, the average speed Va can be estimated and calculated using the following equation. .

[0053]

Va = LcQ / Ot (Equation 3) where Lc is the average vehicle length. Using this formula, the data of a normal vehicle detector that does not directly measure the speed (traffic volume,
The occupation rate) can also create the speed data of FIG.

It should be noted that the speed data measured directly by the vehicle detector or the speed data obtained indirectly by the equation (3) are abnormal for the purpose of estimating the travel time / congestion information with higher accuracy. Checks may be performed.

The following two methods are given as examples of the checking method.

(1) An upper limit value and a lower limit value of the speed are set for each section, and speed data when the speed exceeds the upper limit or falls below the lower limit is regarded as abnormal.

(2) Compared with the past statistical data on the speed for each time zone, the speed data in the case where the speed data is far from a predetermined threshold value or more is regarded as abnormal.

Similarly, it may be checked whether the measured travel time is abnormal or not. At that time, first, an average travel speed is obtained from the actually measured travel time and the section length, and the measured travel time data is calculated for the average travel speed by the same method as one of the two types of abnormality check methods for the speed data. Is also checked for abnormalities.

If at least one of the sensor speed data and the actually measured travel time data is determined to be abnormal for a certain section, the data of FIG. Delete all that one line.

In this manner, a higher-quality correction coefficient DB 15 for achieving more accurate travel time / congestion information estimation can be created.

The correction coefficient creating section 171 is provided in the data storage section 1
The coefficients α and β of Equation 1 are calculated using the actually measured travel time and the vehicle sensor data stored in 70, and a correction coefficient DB
15 is about to be updated.

An example of calculating the coefficients α and β will be described below.

First, the following equation is considered as an example of the evaluation function E separately provided for each section.

[0064]

(Equation 4)

Here, i is the data stored in the data storage unit 170, the measured travel time corresponding to the section, and the number of sets of the sensor speeds, ti is the time, and T is the estimated travel time represented by Formula 1. Time, Tr is the actual travel time of the time, n
Is the number of sensors used in the travel time estimation calculation, α is the respective sensor data correction coefficient used in the travel time estimation calculation, αm is the average value of all αs that are not 0, and a is the first value of Equation 4.
This is a coefficient representing the weight of the second term for the term.

In equation (4), the first term represents the square error between the estimated travel time value and the actually measured value, and the second term represents the sum of the differences between the average value of the correction coefficient α. The second term is the correction coefficient α
In this case, the coefficient a may be set to 0 to make it meaningless.

The combination of the correction coefficients α and β that minimizes the evaluation function E is the solution to be obtained. The solution to find this is a computer-based method such as a GA (Genetic Algorithm) method or a steepest descent method. A general solution that can be easily converged and obtained by the repeated operation may be used.

However, if the measured travel time Tr is not sufficiently obtained, such as when the number of vehicles equipped with on-vehicle devices is small,
The quality of the obtained correction coefficients α and β is often not sufficient in terms of the accuracy of estimating the travel time. Therefore, the correction coefficient α,
Before obtaining β, it may be determined whether or not to perform the correction coefficient calculation process in the target section by comparing the number of actually measured travel times obtained for the target section with a predetermined value.

In order to obtain a higher-quality correction coefficient, not all past data stored in the data storage unit 170 is used, but data to be used is selected by, for example, one of the following methods. May be.

(1) An operator selects data of a desired period from past stored data by using a man-machine.

(2) The past period (for example, one month) of the stored data to be selected is set to be the same for all sections, and the stored data in the period is discarded.

(3) The past period of the storage data to be selected is set for each section, and the storage data for that period is selected for each section.

(4) Among past stored data, data when traffic patterns such as day of the week, season, or weather are different are selected.

Next, the corresponding part of the contents of the original correction coefficient DB 15 is updated so as to be the newly obtained correction coefficient. Here, the timing of updating the correction coefficient DB 15 may be a problem. Since the correction coefficient DB 15 is used for real-time (normally every 5 minutes) calculation processing by the traffic information estimation device 16, it is necessary to update the correction coefficient DB 15 in a time zone (remaining time) during which the real-time calculation processing is not performed. If it is feared that one extra time is not enough to update the correction coefficient DB 15, the original correction coefficient DB is copied to a storage medium different from the original correction coefficient DB, and a plurality of the remaining The new correction coefficient is updated using the time, and when all the updates are completed, the original correction coefficient DB is rewritten to the updated correction coefficient DB using the next remaining time.

In this way, the traffic information estimating device 16
Can update the correction coefficient DB 15 without disturbing the real-time calculation processing by the traffic information estimating apparatus 1 even when such correction coefficients are replaced.
6 enables continuous operation of the traffic information providing system for 24 hours.

The map DB 172 stores the traffic information estimation device 16
Is the same as the map DB 162, and is a database relating to a map defining sections and the like.

The above is the description of the function of each unit constituting the correction coefficient creating device 17.

Next, an example of the processing flow when the correction coefficient DB is created in the correction coefficient creation device 17 using a computer will be described with reference to the flowchart of FIG.

[1] It is determined whether or not a new correction coefficient DB 15 is created. This determination may be made by the operation of the operator, or a predetermined date and time may be obtained using a calendar time of the computer with respect to a time when traffic conditions are expected to change, such as a season or road construction. It may be determined at time to update automatically (90).

[2] The data of the map DB 172 is stored in the memory (91).

[3] It is determined whether or not the number of actually measured travel time data in a section is equal to or greater than a predetermined value. If the value is equal to or more than the predetermined value, the process [4] is executed, and if the value is less than the predetermined value, the process [5] is executed (92).

[4] Correction coefficients α and β are generated by the correction coefficient generation section 171 (93). [5] It is determined whether or not the determination in [3] has been completed for all sections defined in the correction coefficient DB 15. If not finished, repeat [3] to [5]. If the processing has been completed for all sections, the processing [6] is executed (9
4).

[6] It is determined whether or not the correction coefficient DB 15 already stored in the memory can be rewritten, that is, whether or not the correction coefficient DB 15 is currently used or not used in the real-time calculation processing by the traffic information estimation device 16 at this time. I do. If it is used, it waits until it is no longer used, and if it is not used, it can be rewritten, so that the process [7] is executed (95).

[7] The correction coefficient DB 15 is updated by rewriting the memory from the original one to the newly created one (96).

The foregoing has been a description of the functions and specific processing of each unit constituting one embodiment of the traffic information providing system including the travel time / congestion information estimation device according to the present invention.

Next, an application example of the travel time estimation method and apparatus of the present invention will be described.

First, an example of another traffic information providing system using the travel time / congestion information estimation device of the present invention will be described.

For example, as shown in FIG. 10, the travel time estimating section 160 and the traffic congestion information estimating section 161 of the traffic information estimating apparatus 16 are connected to the information providing board 100 or FM online.
A traffic information providing system connected to information providing equipment such as the multiplex broadcasting station 101 can be considered. The information providing board 100 is an electronic bulletin board on the road for displaying traffic information such as real-time travel time information and traffic congestion information estimated by the travel time estimating unit 160 and the traffic congestion information estimating unit 161 by characters or simple figures. Further, the FM multiplex broadcasting station 101 includes a broadcast-type information transmission device that transmits the traffic information to a vehicle-mounted device such as a navigation system by FM multiplex broadcasting.

In such a system, since the traffic information is immediately transmitted to each information providing device, it is possible to provide traffic information in real time to the driver via the information providing device. When this system is realized, it is possible for a driver who does not have an in-vehicle device dedicated to beacons to receive traffic information. As a result, more drivers can select a route while avoiding congestion, and it can be expected that traffic will be dispersed in the road network.

Further, an example of using the estimated travel time output by the travel time estimation method and apparatus of the present invention in a traffic signal control system will be described.

The traffic signal control system shown in FIG. 11 transmits the travel time estimated value obtained by the travel time estimating section 160 and the traffic jam information estimated value obtained by the traffic jam information estimating section 161 to the signal control device 110 and performs signal control. In the device 110, as described in, for example, Japanese Patent Application Laid-Open No. 9-128677, optimal signal parameters are designed in accordance with traffic conditions, a ladder table for each signal is created, and the ladder table is used as an intersection signal 12. , And the intersection traffic light 12 is operated according to the ladder table. As a result, it is possible to dynamically control the intersection traffic light according to the traffic situation, and it is possible to achieve smooth traffic in the road network.

With the above-described method and apparatus for estimating travel time / congestion information and the traffic information providing system to which it is applied, the driver can easily know the travel time data of the target section, so that the driver selects a route while avoiding congestion. It can be expected that traffic will be distributed throughout the road network.

In addition, the traffic signal control system using the travel time / congestion information estimation / estimation device allows the intersection traffic signal to be dynamically operated according to the traffic conditions, thereby achieving smooth traffic in the road network. Becomes possible.

[0094]

According to the present invention, by providing a function of automatically creating a correction coefficient using measurement information from an on-vehicle device, actual running surveys and a lot of work by skilled persons are required. In addition, it is possible to create and update a correction coefficient DB for easily and highly accurately estimating travel time and traffic congestion information, and to predict traffic season and road construction in advance by effectively updating the correction coefficient DB. It is possible to provide a travel time / congestion information estimation method and apparatus which can be adapted to changes in the situation, and a storage medium storing a program for executing the method. This allows
It is possible to greatly reduce man-hours and improve the accuracy of estimating travel time and congestion information.

Further, according to the present invention, traffic information such as estimated travel time or traffic information output by the travel time / congestion information estimating device is transmitted to a driver who does not have a dedicated vehicle-mounted device. Providing an information providing system can be achieved. As a result, the driver can easily know the travel time data of the target section, so that it is possible to select a route while avoiding congestion, and it can be expected that traffic will be dispersed throughout the road network.

Further, according to the present invention, traffic information such as estimated travel time output by the travel time / congestion information estimating device or traffic information is used as input data by the signal control device so that it can be adapted to traffic conditions. Thus, it is possible to achieve a traffic signal control system that dynamically controls a traffic signal. This makes it possible to achieve smooth traffic in the road network.

[Brief description of the drawings]

FIG. 1 is a block diagram showing an embodiment of a traffic information providing system including a travel time / congestion information estimation device according to the present invention.

FIG. 2 is a diagram for explaining a conventional technique for estimating travel time and congestion information of a target section.

FIG. 3 is a diagram illustrating a table of an example of a correction coefficient DB;

FIG. 4 is a graph showing an example of a relationship between a speed V and a traffic jam index I;

FIG. 5 is a graph showing an example of the relationship between the traffic congestion index I and the traffic congestion degree D.

FIG. 6 is a diagram illustrating an example for explaining a method of estimating a congestion length according to a position of a vehicle sensor from which a congestion degree is obtained.

FIG. 7 is a diagram showing a table of an example in which a congestion length is determined based on a combination of congestion degrees of two vehicle sensors in the case of FIG. 6;

FIG. 8 is a diagram illustrating a table of an example of information stored in a data storage unit.

FIG. 9 is a flowchart illustrating an example of a processing flow when a correction coefficient DB is created in a correction coefficient creation device using a computer.

FIG. 10 is a diagram showing an example of another traffic information providing system using the travel time / congestion information estimation device of the present invention.

FIG. 11 is a diagram showing an example of a traffic signal control system using the travel time / congestion information estimation device of the present invention.

[Explanation of symbols]

10: vehicle equipped with on-board equipment, 11: beacon, 12: AVI
System, 13, 20: Vehicle sensor, 14: Information communication unit, 15, 23: Correction coefficient DB, 16: Traffic information estimation device, 17: Correction coefficient creation device, 22, 160: Travel time estimation unit, 24, 161 … Congestion information estimation unit, 25, 16
2,172: Map DB, 100: Information board, 101:
FM multiplex broadcasting station, 110: signal control device, 111: intersection traffic light, 170: data storage unit, 171: correction coefficient creation unit

 ────────────────────────────────────────────────── ─── Continuing on the front page (72) Inventor Takumi Fushiki 7-1-1, Omika-cho, Hitachi City, Ibaraki Prefecture F-term in Hitachi Research Laboratory, Hitachi Ltd. 2F029 AA02 AB01 AB09 AC01 AC06 AC19 AC20 AD01 5B049 AA01 CC02 CC31 DD00 EE01 EE02 EE03 EE07 EE31 FF07 GG02 GG03 GG04 GG09 5H180 AA01 CC01 CC04 CC11 DD01 DD04 EE18 FF01 FF03 FF12 FF13 FF21

Claims (15)

[Claims] 1. Vehicle sensor data measured on a road;
A method for estimating travel time of a target section or traffic congestion information by using a correction database that corrects the vehicle sensor data, wherein actual travel time data obtained from a beacon on the road and vehicle sensor data at that time are estimated. A travel time, wherein the travel time or traffic congestion information of a target section is estimated by using the correction database and the vehicle sensor data, and storing or updating a correction database based on the stored data.・ Congestion information estimation method. 2. A vehicle sensor data measured on a road,
An apparatus for estimating travel time of a target section or traffic congestion information by using a correction database that corrects the vehicle sensor data, wherein measured travel time data obtained from a beacon on the road and vehicle sensor data at that time are estimated. Data storage means for storing data as a pair, correction data creation means for creating or updating a correction database based on the saved data, and traffic information estimation means for estimating travel time or congestion information of a target section using the correction database A travel time / congestion information estimating device comprising: 3. The data stored in the data storage means according to claim 2, wherein the data includes at least one of a predefined section number, a passing time at a start point or an end point of the section, and an actual measurement of the section. A travel time / congestion information estimating device characterized by travel time and speed data by a sensor used for travel time estimation. 4. The data stored in the data storage means according to claim 2 or 3 is determined to be an abnormal value by comparing it with past statistical data or a predetermined threshold value. If there is at least one abnormal value among the stored data collected in one target section, it is necessary to improve the quality of the stored data by deleting the corresponding stored data of the corresponding section from the data storage unit. Characteristic travel time / congestion information estimation device. 5. The correction data generating means according to claim 2, wherein the evaluation function of the target section is a square error between the actually measured travel time and the estimated travel time, and correction data for minimizing the evaluation function is obtained. A travel time / congestion information estimating device characterized by the following. 6. The correction data creating means according to claim 2, wherein the evaluation function of the target section is a sum of a square error between the actually measured travel time and the estimated travel time and an index representing a variation of the correction data, and the evaluation function is defined as An apparatus for estimating travel time / congestion information, wherein correction data to be minimized is obtained. 7. The correction data generating means according to claim 2, wherein the number of actually measured travel time data of the target section stored in the data storage means is compared with a predetermined value to thereby correct the correction data of the section. An apparatus for estimating travel time / congestion information, which determines whether or not to create a new one. 8. The correction data creating means according to claim 2, wherein data of a desired period is selected by a man-machine as data to be used among all the stored data stored in the data storage means. A travel time / congestion information estimating apparatus, characterized in that: 9. The correction data generating means according to claim 2, wherein data of a predetermined past period is selected as data to be used among all the stored data stored in the data storing means. A travel time / congestion information estimating device characterized by the following. 10. The correction data generating means according to claim 2, wherein data to be used when a traffic pattern is different is used as data to be used among all the stored data stored in the data storing means. A travel time / congestion information estimating device characterized by selection. 11. The correction data creating means according to claim 2, wherein the traffic information estimating means determines whether or not the original correction database is used, thereby updating the newly created correction database. A travel time / congestion information estimating device for determining whether or not the travel time / congestion information has been determined. 12. The correction data creating means according to claim 2, wherein the original correction database is temporarily copied to another storage medium, and the newly created correction database is copied by the traffic information estimating means to the original correction database. Update the correction database copied at the unused timing to the newly created correction database, and then update the corrected correction database on another storage medium at the next timing when the original correction database is not used. A travel time / congestion information estimating apparatus, wherein the information is replaced with an original correction database. 13. The correction data generating means according to claim 2, wherein a calendar time of a computer is compared with a predetermined date and time to automatically determine whether or not to newly generate a correction database. A travel time / congestion information estimating device characterized by: 14. A traffic information estimating means in the travel time / congestion information estimating device according to any one of claims 2 to 13, and an information providing board on a road which is connected to said traffic information estimating unit online. Alternatively, a travel time / congestion information estimating device is provided, which is a traffic information providing system that includes an information providing device such as an FM multiplex broadcasting station and provides travel time information to a driver via the information providing device. 15. A traffic information estimating means in the travel time / congestion information estimating device according to any one of claims 2 to 13; and a travel time or congestion information estimated by said traffic information estimating means. Travel time and congestion information estimation, characterized by being a traffic signal control system that includes a signal control device for obtaining a signal parameter and an intersection traffic light connected online with the signal control device, and realizes smooth traffic flow. apparatus.