JP3982525B2 - Method and apparatus for correcting statistical link travel time data - Google Patents

Description

The present invention relates to a method and apparatus for correcting statistical link travel time data.

Oite in Patent Document 1 below, the traffic information received from the traffic information center accumulated as the accumulation with time and day of the week data, the navigation method to obtain the shortest route and required time by using the stored data It is disclosed.

  However, in the above navigation method, the traffic situation estimated from the statistical link travel time data obtained by statistically processing the accumulated data does not always coincide with the current traffic situation, and a difference occurs depending on the situation of the day.

The object of the present invention is to correct the actual link travel time data received from the traffic information center so as to be matched with the current link travel time data obtained from the current traffic information in order to deal with the above-mentioned problem. The purpose is to obtain estimated link travel time data according to the situation.

In order to achieve the above object, the present invention statistically processes link travel time data obtained from traffic information as statistical link travel time data, and adds the statistical link travel to the current link travel time data obtained from current traffic information. Correction is made so as to match the time data, and the corrected statistical link travel time data is further corrected and estimated based on the link travel time data included in the traffic information a predetermined time before the current traffic information. The present invention provides a method for correcting statistical link travel time data, characterized in that the travel time data is link travel time data.
The present invention also stores statistical link travel time data obtained by statistically processing link travel time data obtained from past traffic information in order to apply the above-described statistical link travel time data correction method to an in-vehicle navigation system. Means, statistical link travel time data acquisition means for acquiring the statistical link travel time data corresponding to the current conditions from the storage means, and the acquired statistical link travel in the current link travel time data obtained from the current traffic information First correction means for correcting time data to be matched, and the corrected statistical link travel time data based on link travel time data obtained from traffic information before a predetermined time from the current traffic information. A statistical link travel time data correction device comprising a second correction means for correction. .

According to the statistical link travel time data correction method and apparatus configured as described above, in addition to reflecting the current traffic jam situation, a realistic estimated link trip reflecting the traffic jam situation before a predetermined time. Time data can be obtained.

In carrying out the present invention, the first correction means corrects the acquired statistical link travel time data based on a ratio between the acquired statistical link travel time data and the current link travel time data, or the acquisition The acquired statistical link travel time data is matched with the current link travel time data by correcting the acquired statistical link travel time data based on a time difference between the statistical link travel time data and the current link travel time data. Is desirable.

In carrying out the present invention, the second correction means sets the ratio between the corrected statistical link travel time data and the link travel time data obtained from the traffic information of a predetermined time before the current traffic information. Based on the current traffic information, the corrected statistical link travel time data is further corrected, or the corrected statistical link travel time data centered on the current link travel time data by the second correction means. It is preferable that the corrected statistical link travel time data is rotated on the coordinate plane and further corrected so as to pass the link travel time data obtained from the traffic information before a predetermined time.

  Hereinafter, an embodiment of the present invention will be described with reference to the drawings. In FIG. 1, symbol N indicates a navigation system mounted on an automobile, symbol C indicates a dedicated information communication system provided in the dedicated information center, and symbol T indicates road traffic information communication provided in the road traffic information center. A system (hereinafter also referred to as VICS) is shown. “VICS” is a registered trademark.

  The navigation system N includes a current position detection device 10, which is a GPS reception device that receives radio waves transmitted from an artificial satellite of a satellite navigation system (also referred to as GPS). Thus, the current position of the car is detected together with the current time.

  Further, the navigation system N includes an input device 20, and this input device 20 is a portable remote controller, and by operation thereof, necessary information is received by a receiving unit (illustrated) of a microcomputer 30 (described later). Do not send). Instead of the remote controller, a touch panel attached to a liquid crystal panel (described later) of the output device 60 from the display surface side may be used as the input device 20.

  The navigation system N includes a microcomputer 30, a storage device 40, a wireless communication device 50, and an output device 60. The microcomputer 30 executes the navigation program according to the flowchart shown in FIG. During this execution, the microcomputer 30 is based on the detection output of the current position detection device 10, the operation output of the input device 20, the output of the storage device 40, the output of the wireless communication device 50 and the output of the dedicated information communication system C. Various processing such as map display, guidance route search and route guidance of the car is performed.

  In the present embodiment, the receiving unit is not limited to the one built in the microcomputer 30 but may be one externally attached to the microcomputer 30. The microcomputer 30 operates by being supplied with power from the battery via the ignition switch of the automobile and starts executing the navigation program. Note that the navigation program is written in advance in the ROM of the microcomputer 30 so that the microcomputer 30 can read it.

  The storage device 40 is a hard disk, and a series of map data and traffic information data is stored in the storage device 40 as a database so that it can be read out by the microcomputer 30. The wireless communication device 50 receives road traffic information from the dedicated information communication system C and outputs it to the microcomputer 30.

  The output device 60 is a display device, and displays data necessary for the vehicle as information under the control of the microcomputer 30. The output device 60 is disposed on an instrument panel provided on the front wall of the vehicle interior of the vehicle, such as a liquid crystal panel.

  The dedicated information communication system C includes a server 70, a wireless communication device 80, and a storage device 90. The server 70 executes the server program according to the flowcharts shown in FIGS. The server 70 performs transmission / reception processing between the wireless communication device 50 and VICST via the wireless communication device 80 during execution of the server program. The server program is written in advance in the ROM of the server 70 so as to be readable by the server 70.

  In the storage device 90, traffic information data such as link travel time, vehicle speed, degree of congestion, traffic stoppage or traffic restriction transmitted from the VICST is stored in the database of the storage device 90 as VICS data. Here, the degree of traffic congestion D refers to the degree of traffic congestion. The traffic congestion degree D includes, for example, “congested”, “congested”, “no traffic jam” data and “unknown” from the higher level of traffic jam. There are four levels of data. Note that the degree of congestion D is not limited to four stages, and may generally be a plurality of stages.

  In the present embodiment configured as described above, it is assumed that the vehicle has started running. Accordingly, the microcomputer 30 starts executing the navigation program according to the flowchart of FIG. If there is no display request from the input device 20 at this stage, the determination of NO is repeated in step 100 of FIG.

  In such a state, if there is a request to display a desired map by the input device 20, it is determined as YES in Step 100. Thereafter, in step 200, map data representing the desired map (hereinafter also referred to as desired map data) is read from the storage device 40. Accordingly, the desired map data is read from the database of the storage device 40. Then, in step 300, the desired map display process is performed. Accordingly, the output device 60 displays a desired map on the display panel based on the desired map data.

  When the process in step 300 is completed as described above, in step 400, it is determined whether or not a destination is selected. If the destination is not input to the microcomputer 30 by operating the input device 20 at the current stage, the determination of NO is repeated in step 400.

  In such a state, if the destination has been input to the microcomputer 30 by operating the input device 20, the determination in step 400 is YES because the destination has been selected. Thereafter, in step 500, transmission processing of the current position, the destination, and the departure date / time detected by the current position detection device 10 is performed. Accordingly, the data on the current position, the destination, and the departure date / time are transmitted from the microcomputer 30 to the dedicated information communication system C via the wireless communication device 50.

  On the other hand, in the dedicated information communication system C, the server 70 repeats the determination of NO in step 610 of FIG. In such a state, when the server 70 receives the data of the current position and the destination from the wireless communication device 50 via the wireless communication device 80, it is determined as YES in Step 610.

  Thereafter, in step 620, statistical link travel time data acquisition processing from the storage device 90 is performed. Along with this, the link travel time of each link (link determined by the current location and the destination) for a predetermined period corresponding to conditions appropriate to the current date and time, for example, the day of the week, time, weather, etc. The corresponding time is read from the database of the storage device 90 as statistical link travel time data. The predetermined period may be, for example, one day or several hours.

  Next, in step 630, current status data acquisition processing is performed. Accordingly, the server 70 acquires the link travel time currently received for each link from the VICST (hereinafter also referred to as the current link travel time Tp) and other traffic information through the wireless communication device 80 as current status data.

Next, the processing of the matching correction processing routine 640 (see FIG. 4) is performed as follows. First, in step 641 of FIG. 4, a first ratio calculation process is performed. Accordingly, as shown in FIG. 5, the server 70 has a ratio (hereinafter referred to as a first ratio R ₁₎ between the current link travel time Tp and the link travel time Ts estimated from the statistical link travel time data for each link. Are calculated according to the equation (1).

R ₁ = Tp / Ts (Equation 1)
Next, in step 642, a first ratio correction process is performed. Accordingly, the server 70 accumulates the first ratio R ₁ corresponding to the statistical link travel time data for each link based on each of the first ratios R _{1. As} shown in FIG. A ratio correction line (see the broken line portion in FIG. 5) is calculated.

  Next, in step 643, time axis movement processing is performed. Accordingly, as shown in FIG. 5, the server 70 temporarily moves the time axis vertically on the coordinate plane so that the current link travel time Tp becomes 0 (s). The coordinate plane is an orthogonal coordinate plane between the link travel time axis (vertical axis) and the time axis (horizontal axis) as shown in FIG.

Thereafter, in step 644, a second ratio calculation process is performed. Accordingly, as shown in FIG. 5, the server 70 calculates the link travel time Tpb before the current unit time (for example, 5 minutes) and the link travel time Tsb on the first ratio correction line corresponding to that time. The ratio (hereinafter also referred to as the second ratio R ₂ ) is calculated according to the formula 2 below.

R ₂ = Tpb / Tsb (Equation 2)
For example, as shown in FIG. 5, the link travel time Tpb before the unit time of the current time after moving the time axis is −5 (s), and the link travel time Tsb based on the first ratio correction line corresponding to that time. Is −20 (s), the second ratio R ₂ is −5 / −20 = 0.25.

Next, in step 645, matching correction processing of estimated link travel time data is performed. Accordingly, as shown in FIG. 6, the server 70 integrates the second ratio R ₂ on the first ratio correction line based on the second ratio R ₂ calculated in step 644, and links travel time data ( Hereinafter, estimated link travel time data (also referred to as a broken line portion in FIG. 6) is estimated.

  Thereafter, in step 650, traffic information transmission processing is performed. Accordingly, the server 70 transmits the estimated link travel time data and other traffic information for each link calculated in the matching correction processing routine 640 to the microcomputer 30 via the wireless communication device 80 and the wireless communication device 50. .

  As described above, the statistical link travel time data obtained by statistically processing the past accumulated data is corrected based on the ratio between the link travel time Ts estimated by the statistical link travel time data and the current link travel time Tp. Therefore, the corrected statistical link travel time data can be used as highly reliable statistical data reflecting the current traffic congestion situation.

  The corrected statistical link travel time data is estimated link travel time data based on the ratio of the link travel time Tsb estimated by the corrected statistical link travel time data to the link travel time Tpb before the unit time. It is corrected. Therefore, the estimated link travel time data can be used as more realistic data reflecting the traffic congestion status before the unit time in addition to the current traffic congestion status.

  Therefore, the navigation system N can perform highly reliable route guidance by using the estimated link travel time data as traffic congestion prediction data.

  After the processing in the dedicated information communication system C is completed as described above, when the wireless communication device 50 receives the traffic information including the estimated link travel time data from the dedicated information communication system C and outputs it to the microcomputer 30, In step 500a of FIG. 2, it is determined YES.

  Thereafter, the microcomputer 30 accumulates traffic information including estimated link travel time data received via the wireless communication device 50 in the database of the storage device 40. Next, a guide route search process is performed based on the estimated link travel time data in step 700, and based on the guide route searched in this process, a route guide process taking into account the congestion prediction is started in step 800. .

In carrying out the present invention, the following various modifications are possible without being limited to the above embodiment.
(1) The first ratio correction process in step 642 described above not only uses the first ratio correction line based on the first ratio R ₁ but also is estimated based on the current link travel time Tp and the statistical link travel time data, for example. It is also possible to calculate a time difference from the link travel time Ts and use a correction line obtained by dividing the time difference from the statistical link travel time data based on this time difference.

Even if such correction processing is performed, the corrected statistical link travel time data can be used as highly reliable statistical data reflecting the current traffic jam situation.
(2) The second ratio calculation process in step 644 described above not only uses the second ratio R ₂ between the link travel time Tpb before the unit time of the current time and the statistical link travel time data Tsb corresponding to that time. For example, a ratio between a link travel time that is a predetermined time before the current time and statistical link travel time data corresponding to that time may be used.

Further, a ratio between a plurality of link travel times before a predetermined time before the current time and statistical link travel time data corresponding to those times may be used.
(3) In the above-described matching correction processing routine 640, not only the estimated link travel time data based on the second ratio R ₂ in steps 643 to 645 described above is used, but also, for example, as shown in FIG. Estimated link travel time data obtained by rotating the first ratio correction line obtained in step 642 around the travel time Tp so as to pass through the link travel time Tpb before the predetermined time on the XY coordinate plane. (See the broken line portion in FIG. 7). The term “before the predetermined time” may be, for example, a unit time before the current time.

This estimated link travel time data can be used as more realistic data reflecting the traffic conditions before the unit time in addition to the current traffic conditions, and in particular, the link travel before the predetermined time of the time This is effective when the difference between the time Tpb and the link travel time based on the first ratio correction line corresponding to the unit time is small.
(4) The dedicated communication information system C described above receives the VICS data from the road traffic information center, performs the processing in steps 620 to 640 described above, and transmits it to the navigation system N. The navigation system N directly Alternatively, the VICS data from the road traffic information center may be received and the processing in steps 620 to 640 described above may be performed.

It is a block diagram which shows one Embodiment of this invention. It is a flowchart showing the program for navigation performed with the microcomputer of FIG. It is a flowchart showing the server program run in the server of the private information communication system of FIG. 4 is a detailed flowchart of a matching correction processing routine of FIG. 3. It is a figure which shows the relationship between the present link travel time, statistical link travel time data, and a 1st ratio correction line. It is a figure which shows the relationship between the present link travel time, statistical link travel time data, and estimated link travel time data. It is a figure which shows the relationship between the present link travel time, statistical link travel time data, and estimated link travel time data.

Explanation of symbols

C: Dedicated information communication system, N: Navigation system, R ₁ ... First ratio, R ₂ ... Second ratio, T ... VICS, Tp ... Current link travel time, Tpb ... Link travel time before unit time, Ts ... Statistics Link travel time estimated from link travel time data, Tsb ... Link travel time before unit time estimated from statistical link travel time data, 30 ... Microcomputer, 70 ... Server, 90 ... Storage device.

Claims (6)

Statistically processing the link travel time data obtained from the traffic information as a statistical link travel time data is corrected so as to match the statistical link travel time data to the current link travel time data obtained from the current traffic information, the correction The statistical link travel time data after that is further corrected based on the link travel time data included in the traffic information a predetermined time before the current traffic information to obtain estimated link travel time data. Link travel time data correction method. Storage means for storing statistical link travel time data obtained by statistically processing link travel time data obtained from past traffic information;
  Statistical link travel time data acquisition means for acquiring the statistical link travel time data corresponding to the current condition from the storage means;
  First correction means for correcting the current link travel time data obtained from current traffic information to match the acquired statistical link travel time data;
  Second correction means for further correcting the corrected statistical link travel time data based on link travel time data obtained from traffic information before a predetermined time from the current traffic information;
A statistical link travel time data correction apparatus comprising: 2. The statistics according to claim 1, wherein the first correction unit corrects the acquired statistical link travel time data based on a ratio between the acquired statistical link travel time data and the current link travel time data. Link travel time data correction device. 2. The statistics according to claim 1, wherein the first correction unit corrects the acquired statistical link travel time data based on a time difference between the acquired statistical link travel time data and the current link travel time data. Link travel time data correction device. The second correction unit is configured to adjust the corrected statistical link travel based on a ratio between the corrected statistical link travel time data and link travel time data obtained from traffic information before a predetermined time from current traffic information. The apparatus for correcting statistical link travel time data according to claim 1, further comprising correcting the time data. The second correction means uses the corrected statistical link travel time data as traffic information in which the corrected statistical link travel time data centered on the current link travel time data is a predetermined time before the current traffic information. 2. The statistical link travel time data correction device according to claim 1, wherein the travel time data is rotated on a coordinate plane so as to pass through the link travel time data obtained from (1).

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