JP2009140292A - Traffic information calculation device, traffic information calculation program, and traffic information calculation method - Google Patents

Abstract

To obtain travel time information using probe vehicle information, an accurate travel time is obtained in consideration of waiting for a signal, and traffic information such as a degree of traffic congestion is accurately determined.
Data on the position and speed of a vehicle traveling on a road section is collected (S1), and the number of signal waits and signal waiting time on the road section of the vehicle based on the collected speed V of the vehicle. (S6), and subtracting the signal waiting time from the travel time of the road section (S8), the net travel time of the road section is calculated, and the road is calculated based on the net travel time. Traffic information such as the congestion level of the section is determined (S10).
[Selection] Figure 4

Description

  A vehicle capable of uplinking information such as the travel trajectory and speed of the vehicle to the ground system is called a “probe vehicle”. The present invention collects information (referred to as probe information) such as the travel trajectory and vehicle speed of the probe vehicle, analyzes the behavior of the probe vehicle based on the probe information, obtains the travel time of the road section from the behavior, It is related with the technique which calculates traffic information.

The travel time required to pass through the road section is information necessary for grasping and predicting traffic congestion on the road. If the speed of the vehicle is known, the degree of traffic congestion can be obtained step by step such as traffic congestion, congestion, and smoothness according to the travel time value obtained from the vehicle speed.
To find the travel time, it is only necessary to install a TV camera on the road and measure the vehicle speed. To measure the vehicle speed on each road in detail, it is necessary to install a large number of TV cameras, which is very expensive. It will be. If the installation of the TV camera is limited to some main roads, only the speed of the main road is known, and the traffic situation of the entire road cannot be predicted accurately.

Thus, it has been proposed to obtain travel time information using probe information of a probe vehicle traveling on a road.
JP 2004-101504 A

  When travel time information is obtained using probe information and the degree of traffic congestion is calculated, a vehicle may wait for a signal in a road section. In this case, if the signal waiting time is not taken into account, an incorrect traffic congestion level is displayed. In particular, in the case of a short road section, even if it is not crowded at all, the traffic congestion degree information of the road section may be provided as traffic jam or congestion due to the influence of a single signal waiting time. Will give.

  Accordingly, the present invention provides a traffic information calculation device and a traffic information calculation capable of accurately calculating traffic information such as the degree of traffic congestion considering that there is a signal waiting when travel time information is obtained using probe information. The purpose is to provide a program and a traffic information calculation method.

  The traffic information calculation apparatus according to the present invention includes a data collection unit that collects position / speed data of a vehicle traveling on a road section, and the road of the vehicle based on the position / speed of the vehicle collected by the data collection unit. Considering the signal waiting calculation means for calculating the presence or absence of signal waiting in the section and the signal waiting time, the presence or absence of signal waiting in the road section calculated by the signal waiting calculation means, and the signal waiting time, Traffic information calculation means for calculating the net travel time of the road section by subtracting the signal waiting time from the travel time of the road section, and calculating the traffic information of the road section based on the net travel time Are provided. As a specific example of the traffic information, there is a congestion degree.

  With this traffic information calculation device, when calculating the travel time of a certain road section from the collected vehicle position / speed data, the stop time due to waiting for a signal can be distinguished and calculated. Therefore, the net travel time excluding the signal waiting time can be obtained, the average speed can be calculated from the net travel time, and the traffic information can be accurately calculated according to the average speed. When collecting the position / speed data of the vehicle, the position data and speed data may be acquired as they are, or may be acquired by acquiring the position data and calculating the speed data from the position data.

The traffic information calculation device may be constituted by a road device (for example, the ground processing center 2 described in the best mode for carrying out the invention), may be constituted only by an in-vehicle device, a mobile phone, etc. You may comprise only the terminal device.
The signal waiting calculation means determines that there is a signal waiting on the condition that the stop position of the vehicle at the intersection is within the first predetermined distance D1 before the intersection when determining whether or not to wait for the signal. It is preferable to do. The first predetermined distance D1 may be a maximum distance at which the vehicle stops at the intersection to wait for a normal signal. When the vehicle stops before this first predetermined distance D1, the first predetermined distance D1 may be set so that it can be determined that the vehicle has stopped for a purpose other than waiting for a signal.

  The signal waiting calculation means determines whether or not there is a signal waiting when the vehicle speed reaches a threshold value at any point within a second predetermined distance (D2; D2> D1) before the intersection. It is determined whether or not the vehicle speed exceeds the threshold at any point within the third predetermined distance (D3) ahead of the intersection, and if both exceed the threshold, there is a signal waiting. It is preferable to judge. The reason for making this determination is to confirm that the vehicle was running smoothly before reaching the intersection, and to confirm that the vehicle was running smoothly after leaving the intersection.

  The traffic information calculation means calculates the number of signal waiting times at the intersection of the vehicle, and when the number of signal waiting times is N (N is a predetermined integer of 2 or more) times or more, from the travel time of the road section Traffic information such as the degree of congestion on the road section may be calculated without subtracting the signal waiting time. In this configuration, when waiting for a signal multiple times for one intersection, the signal waiting is regarded as a part of the traffic jam and the traffic jam degree is calculated without deleting the signal waiting time from the travel time. Accordingly, the driver can determine the degree of traffic congestion that matches the actual situation of the road.

In addition, the traffic information calculation program of the present invention is a program that is stored and executed in a computer, and is a program according to the same invention as the traffic information calculation device.
Moreover, the traffic information calculation method of the present invention is a method according to the same invention as the invention of the traffic information calculation device.

  As described above, according to the present invention, it is possible to obtain the correct degree of traffic congestion even when it is conventionally determined that the traffic is congested or jammed due to the influence of waiting for a signal even though the road is free.

Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings.
FIG. 1 is a diagram showing an overall configuration of a traffic information calculation system including a traffic information calculation device according to the present invention.
The traffic information calculation system includes an in-vehicle device 1 mounted on a probe vehicle and a ground processing center 2. The ground processing center 2 functions as the traffic information calculation device of the present invention. Since the traffic information calculation device can be configured with only the in-vehicle device 1 and the traffic information calculation device can be configured with only the mobile phone, the description thereof will be described later.

  The in-vehicle device 1 has a code for vehicle identification and vehicle type identification, and can communicate with the ground processing center 2 using this code. The in-vehicle device 1 acquires probe information such as time, position of the vehicle for each time, speed, and the like, and transmits the acquired probe information. The in-vehicle device 1 may transmit position information for each time. In this case, the speed information can be obtained by calculation at the ground processing center 2.

The ground processing center 2 uses the probe information collected from the in-vehicle device 1 to calculate the travel time and the degree of congestion on the road section (referring to the road from the intersection to the intersection).
As a communication means between the in-vehicle device 1 and the ground processing center 2, a wide area communication system such as a mobile phone can be used. Further, if it is assumed that the communication is performed via a road communication device, a communication method with a relatively narrow area such as an optical beacon, a wireless LAN, or a DSRC (Dedicated Short Range Communication) between the in-vehicle device 1 and the road communication device. In this case, the road communication device and the ground processing center 2 are connected by a dedicated communication line.

  FIG. 2 is a block diagram showing an internal configuration of the in-vehicle device. The in-vehicle device 1 includes a communication device (cell phone or the like) 11 that performs road-to-vehicle communication with the ground processing center 2, a GPS receiver 13 that detects a vehicle position at each time using radio waves of an artificial satellite, A vehicle speed sensor 15 that obtains vehicle speed data based on speed pulses, a direction sensor 17 that obtains vehicle direction data, a GPS receiver 13, a vehicle speed sensor 15, a direction sensor 17 and the like. And a memory 21 for temporarily storing the calculated time, position and speed data.

  In addition to inputting data from the GPS receiver 13, the vehicle speed sensor 15, and the direction sensor 17, the arithmetic unit 19 has operated the vehicle steering, stepped on the vehicle brake, stepped on the accelerator, The switch or actuator detects that the instrument has been operated, the headlight (front light) has been turned on, the ABS has been activated, and the wiper has been operated, and the detection signal is input. Information obtained through these switches or actuators is referred to as “vehicle auxiliary information”. The arithmetic device 19 acquires the probe information and the vehicle auxiliary information and provides them to the communication device 11.

  FIG. 3 is a block diagram showing the internal configuration of the ground processing center 2. The ground processing center 2 includes a receiver 31 that receives a communication signal including probe information and the like, a data extraction unit 33 that extracts probe information and the like from the communication signal, and a travel time and a congestion degree of a road section based on the probe information. A traffic information calculation unit 35 to calculate and road map data 37 used for link matching processing are provided. The data extraction unit 33 functions as a “data collection unit”.

  The travel time / congestion degree calculation process performed by the traffic information calculation unit 35 of the ground processing center 2 will be described in detail with reference to a flowchart (FIG. 4). All or part of this processing function is realized by the computer of the ground processing center 2 executing a travel time / congestion degree calculation program recorded on a predetermined medium such as a CD-ROM or hard disk of the ground processing center 2. The

First, probe information is acquired from one or a plurality of probe vehicles (step S1). Based on the probe information, link matching processing (processing for causing the trajectory of the probe vehicle to follow the road section on the map) is performed (step S2), the road section on which each probe vehicle has traveled is identified, and Specify the travel time and time zone.
Paying attention to a certain road section, a relationship between the speed V at which a certain probe vehicle travels on the road section and time t is obtained.

  In FIG. 5, the graph showing the relationship between the speed V of the vehicle of the said road area and time t is shown. The traffic information calculation unit 35 obtains a time T when the speed V falls below a threshold value Vst for determining whether the vehicle is stopped (step S3). The threshold value Vst is set to a sufficiently small value (for example, 1 km / h) at which it can be determined that the vehicle has stopped. When the time T exceeds a certain reference time (for example, 3 minutes), it is regarded as a longer stop, not a signal stop (YES in step S3). If there is a “long stop”, the speed data for that time is excluded from the travel time calculation (step S4). This prevents the travel time from becoming a large value different from the actual time.

And it is judged whether there was a signal waiting stop (step S5).
The determination method of this signal waiting stop will be described in detail. 6A shows a road map including one road section from the intersection to the next intersection. FIG. 6B shows the distance along the road section on the horizontal axis and the speed V of the probe vehicle on the vertical axis. It is a graph taken. The reason why the distance along the road section and the speed V of the probe vehicle can be matched in this way is because the above-described link matching process has been performed.

Attention is paid to the intersection C existing at the exit position of the road section. A position (indicated by a white triangle in FIG. 6B) corresponding to the stop line 5 (being the end point of the road section) at the intersection C is L0, and a predetermined distance D1 (for example, 150 m) before the stop line position L0. ) Is set. A section of the predetermined distance D1 before the stop line position L0 is referred to as a “signal waiting stop section”.
Further, a predetermined distance D3 ahead of the position L0 of the stop line is set. The predetermined distance D3 is preferably a distance longer than the width W of the intersection. For example, if the width W of the intersection is 20 m, the predetermined distance D3 is a longer distance, for example 150 m.

FIG. 7 is a flowchart for explaining in detail the signal waiting stop determination method (step S5), and will be described below with reference to this flowchart.
The position at which the speed V of the probe vehicle is below the threshold value Vst and the speed V of the probe vehicle is minimum is set as the stop position of the probe vehicle (shown by a black triangle in FIG. 6; step S51).

The traffic information calculation unit 35 confirms whether or not the stop position is within a predetermined distance D1 before the intersection, that is, is in the signal waiting stop section (step S52). If it is not in the signal waiting stop section, it is determined that the stop is not a stop for waiting for a signal before the signal. As a “stop other than a stop for waiting for a signal”, a temporary stop in a traffic jam is exemplified.
When the stop position is in the signal waiting stop section, the threshold value for the speed V of the probe vehicle to determine the smooth running of the vehicle before the signal waiting stop section and before the signal waiting stop section. It is determined whether or not Vgo has been exceeded (steps S53 and S54). Specifically, at any point within a predetermined distance D2 (D2>D1; for example, D2 = 300 m) before the intersection stop line, the probe vehicle speed V is a threshold value Vgo (for example, 20 km / h). Is determined (step S53), and it is determined whether the speed V of the probe vehicle exceeds the threshold value Vgo at any point within the predetermined distance D3 from the stop line of the intersection (step S54). If the threshold value Vgo is exceeded at any point within the predetermined distance D2 and any point within the predetermined distance D3, the vehicle travels smoothly toward the intersection, decelerates due to a red light, and stops. It can be determined that the vehicle has started at a green light, accelerated to exit the intersection, and has entered smoothly (step S55). If the threshold value Vgo is not exceeded at any point within the predetermined distance D2 or any point within the predetermined distance D3, it is determined that the stop is not for signal waiting. If the threshold value Vgo is not exceeded within the predetermined distances D2 and D3, it is determined that the stop is not for waiting for a signal. Although it may stop temporarily within the range, since this stop is not a stop due to signal waiting, this is to exclude it from the signal waiting time.

By performing the above determination, it is possible to correctly determine that the probe vehicle has waited for a signal at the intersection.
In the road section, the probe vehicle may perform a signal waiting stop a plurality of times. In the flowchart of FIG. 4; in step S6, the number of signal waiting times and the signal waiting time for each signal waiting (corresponding to T in FIG. 5) are calculated. A method for calculating the number of signal waiting times will be described with reference to FIG.

FIG. 8 is a diagram for explaining the method for determining the number of signal waiting times. FIG. 8A shows a road map including one road section from the intersection to the next intersection, and FIG. 8B shows the road section. Is a graph with the horizontal axis representing the distance along the vertical axis and the velocity V of the probe vehicle on the vertical axis. The signal waiting stop position of the probe vehicle is illustrated by two black triangles.
When counting the number of signal stop positions, such a case must be excluded because the vehicle may move gradually while waiting for one red signal. Therefore, in order to determine that the vehicle is a separate stop, the distance between adjacent stop positions (indicated by “U” in FIG. 8) is a predetermined distance (for example, 10 m) or the interval between adjacent stop points is a predetermined time (For example, 30 seconds) or more may be a condition.

  When multiple signal waits occur for one road section in this way, the signal wait is also considered as part of the traffic jam, and the traffic congestion degree is calculated from the travel time as it is without subtracting the signal wait time from the travel time. Good. In step S7, it is determined whether the number of signal waiting times is equal to or greater than a reference value N (N is a constant equal to or greater than 2). If N is greater than or equal to N, the process of subtracting the signal waiting time from the travel time is skipped. As an example of N, N = 2 for a normal intersection and N = 3 for an intersection with a large amount of traffic.

  When the probe vehicle waits for a signal less than N times, the signal waiting time is subtracted from the travel time of the probe vehicle in the road section (step S8). Then, the speed of the probe vehicle is obtained from the distance of the road section using the subtracted travel time, or when the probe vehicle is waiting for a signal N times or more, using the travel time as it is ( Step S9). This speed is not an instantaneous speed, but may be referred to as an “average speed” because it is an average speed during traveling on the road section.

  Then, the degree of traffic jam is calculated from the calculated average speed (step S10). For example, in the case of a general road, “smooth” if the average speed is 20 km / h or more, “congestion” if it is 10 km / h or more and less than 20 km / h, “congestion” if it is less than 10 km / h. In the case of an intercity expressway, “average” is “smooth” if the average speed is 60 km / h or more, “congestion” if it is 40 km / h or more and less than 60 km / h, and “congestion” if it is less than 40 km / h. In the case of an urban expressway, “smooth” is obtained if the average speed is 40 km / h or more, “congestion” if it is 20 km / h or more and less than 40 km / h, and “congestion” if it is less than 20 km / h. These speed thresholds are referred to as “smooth / congestion / congestion judgment speed thresholds”.

The above process is also performed for other road sections, and if all the target road sections are finished, the whole process is finished (YES in step S11).
The following items should be taken into consideration when determining whether to stop waiting for a signal.
Considering the headlight information, ABS operation information, and wiper information among the vehicle auxiliary information when traveling on the road section, the headlight is on (nighttime), ABS operation (freezing), and wiper operation (rainy). Since the speed becomes lower as a whole, the threshold value Vgo for determining normal driving of the vehicle may be set to a value smaller than normal.

In addition, the threshold value is considered in consideration of the road type of the road section (expressway (between cities, in the city) / national road / main road / narrow street, etc.), link type (main line / connecting road / ramp road, etc.), and road width. Vgo, predetermined distances D2 and D3, smooth / congestion / congestion determination speed threshold (hereinafter referred to as “various thresholds”) may be changed. For example, the size of various threshold values is as follows.
Road type: Intercity highway> Intracity highway> National highway> Main road> Narrow street Link type: Main line> Connected road> Ramp road Road width: Wide road> Narrow road.

Further, various threshold values may be changed in consideration of the road shape (straight line, curve point, before curve, uphill, downhill, etc.). For example, the threshold value for each shape is as follows.
Road shape: Main line (down)> Main line (up)> Before curve> Curve point.
Information on the degree of traffic congestion calculated as described above can be transmitted from the ground processing center 2 to the in-vehicle device 1 and transmitted to the driver through the in-vehicle device 1.

  At the same time, the ground processing center 2 calculates the average signal waiting time and the average number of signal waiting times for each road section from the probe information of each vehicle, and transmits the information to the in-vehicle device 1. By using it, it is possible to guide the driver by screen display, voice, or the like before the intersection. Therefore, the driver can obtain a sense of security by knowing the signal waiting time at the intersection where the driver wants to know the front intersection and information, and the number of signal waiting times. Further, by knowing the signal waiting time and the number of times, it is possible to estimate the degree of congestion of the road and avoid the crowded road.

In addition, information on traffic congestion level, average waiting time for signal and number of waiting times for signal is calculated according to the time of day, day of the week, weather, bon festival, GW, special day, etc. by statistical processing of past data. It can also be provided according to.
Although the embodiments of the present invention have been described above, the embodiments of the present invention are not limited to the above-described embodiments. For example, in the description so far, probe information collection processing and travel time / congestion degree calculation processing are all performed by the ground processing center 2, but all of these processing may be performed by an in-vehicle device. Also, probe information collection processing and travel time / congestion degree calculation processing may be performed using a mobile phone having a GPS position detection function.

  The travel time / congestion degree calculation process performed by the vehicle-mounted device alone will be described with reference to FIG. FIG. 9 is a block diagram of an in-vehicle device that performs probe information acquisition and travel time / congestion degree calculation processing. The in-vehicle device 1 includes various data obtained from a GPS receiver 13, a vehicle speed sensor 15, an orientation sensor 17, and the like. A calculation device 19 that calculates the position / speed of the vehicle based on the vehicle, a traffic information calculation unit 35 that calculates the travel time / congestion level based on the position / speed of the vehicle, and road map data 37 used for link matching processing. ing. The function of each block is as described in the apparatus configuration of FIG. 2 and the apparatus configuration of FIG. The embodiment of FIG. 9 is characterized in that the travel time / congestion degree can be calculated by the in-vehicle device 1 alone. If it is an in-vehicle device that can perform inter-vehicle communication with other probe vehicles, the probe information of the other probe vehicles is received, and the travel time / congestion degree is more accurately obtained using a plurality of probe information. Can also be calculated.

  A configuration for performing travel time / congestion degree calculation processing by a mobile phone alone will be described with reference to FIG. FIG. 10 is a block diagram of a mobile phone 1 ′ that performs probe information acquisition and travel time / congestion level calculation processing. The mobile phone 1 ′ is based on data obtained from a built-in GPS receiver 13. An arithmetic unit 19 that calculates a position and calculates a speed based on a change in position, a traffic information calculation unit 35 that calculates a travel time / congestion level based on the position / speed of the vehicle, and a road map used for link matching processing Data 37 is provided. The function of each block is as described in the apparatus configuration of FIG. 2 and the apparatus configuration of FIG. The calculated travel time and traffic jam information can be output and displayed on the screen of a mobile phone.

It is a figure which shows the whole structure of the traffic information calculation system containing the traffic information calculation apparatus of this invention. It is a block diagram which shows the internal structure of a vehicle-mounted apparatus. It is a block diagram which shows the internal structure of a ground processing center. It is a flowchart for demonstrating the travel time and traffic congestion degree calculation process which considered the signal waiting time of the vehicle. It is a graph which shows the time change of the speed V of a vehicle at the time of road area driving | running | working. (A) shows a road map including a road section from the intersection to the intersection, and (b) is a graph showing a change in the speed V of the probe vehicle before and after the intersection with the distance along the road section as the horizontal axis. . It is a flowchart for demonstrating in detail the signal waiting stop determination method. (A) shows a road map including a road section from the intersection to the intersection, and (b) is a graph showing a change in the speed V of the probe vehicle before and after the intersection with the distance along the road section as the horizontal axis. . It is a block diagram of the in-vehicle device which performs acquisition of probe information and travel time / congestion degree calculation processing. FIG. 3 is a block diagram of a mobile phone 1 ′ that performs probe information acquisition and travel time / congestion degree calculation processing.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 In-vehicle apparatus 2 Ground processing center 11 Communication apparatus 13 GPS receiver 15 Vehicle speed sensor 17 Direction sensor 19 Computation apparatus 21 Memory 31 Receiver 33 Data extraction part 35 Traffic information calculation part 37 Road map data

Claims (6)

Data collecting means for collecting position / speed data of a vehicle traveling on a road section;
Based on the position and speed of the vehicle collected by the data collection means, signal waiting calculation means for calculating the presence or absence of signal waiting and signal waiting time in the road section of the vehicle;
Considering the presence / absence of the signal in the road section calculated by the signal waiting calculation means and the signal waiting time, the net waiting time of the road section is subtracted from the travel time of the road section by subtracting the signal waiting time. A traffic information calculating device comprising: a traffic information calculating means for calculating the traffic time of the road section based on the net travel time.   When the signal waiting calculation means determines whether or not there is a signal waiting, there is a signal waiting on the condition that the stop position of the vehicle at the intersection is within the first predetermined distance (D1) before the intersection. The traffic information calculation device according to claim 1, wherein the traffic information is calculated.   The signal waiting calculation means determines whether or not there is a signal waiting when the vehicle speed reaches a threshold value at any point within a second predetermined distance (D2; D2> D1) before the intersection. It is determined whether or not the vehicle speed exceeds the threshold at any point within the third predetermined distance (D3) ahead of the intersection, and if both exceed the threshold, there is a signal waiting. The traffic information calculation device according to claim 2, which is to be determined.   The traffic information calculation means calculates the number of signal waiting times at the intersection of the vehicle, and when the number of signal waiting times is N times (N is a predetermined integer of 2 or more), the traffic information is calculated from the travel time of the road section. The traffic information calculation device according to claim 1, wherein the traffic information of the road section is calculated without subtracting the signal waiting time. A traffic information calculation program executed by being stored in a computer,
Collecting position / speed data of vehicles traveling on road sections;
Based on the collected position / velocity of the vehicle, calculating a signal waiting time and a signal waiting time in the road section of the vehicle;
The net travel time of the road section is calculated by subtracting the signal wait time from the travel time of the road section in consideration of the calculated signal waiting time in the road section and the signal wait time. A traffic information calculation program comprising: calculating and calculating traffic information such as a degree of traffic congestion in the road section based on the net travel time. Collect the position and speed data of vehicles traveling on the road section,
Based on the collected position / speed of the vehicle, the presence / absence of signal waiting in the road section of the vehicle and the signal waiting time are calculated,
The net travel time of the road section is calculated by subtracting the signal wait time from the travel time of the road section in consideration of the calculated signal waiting time in the road section and the signal wait time. A traffic information calculation method characterized by calculating traffic information such as a traffic congestion degree of the road section based on the net travel time.

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