JP5249556B2 - On-board device for travel route detection - Google Patents

Description

The present invention relates to a vehicle-mounted device for detecting a travel route.
More specifically, in the present invention, when a route on which the vehicle has traveled is obtained by performing map matching processing using the estimated position obtained based on data from a GPS receiver or the like and road information, The present invention is devised so that the travel route can be accurately determined while having a simple configuration in terms of hardware and software.

As an automatic toll collection system on a toll road, there is a wireless toll collection system. This wireless toll collection system performs vehicle recognition, authentication, and settlement by communicating between a base station installed at a toll gate on a toll road and an in-vehicle device mounted on a vehicle (automobile). is there.
By using such a wireless toll collection system, it is possible to pass through the toll gate non-stop and cashless.

  Further, a GPS road billing system that uses the GPS (Global Positioning System) and detects a vehicle position, a travel route, and a travel distance as a next system of the wireless toll collection system is being studied.

  In this GPS road billing system, radio waves transmitted from GPS satellites are received by a GPS receiver provided in the vehicle-mounted device. The GPS receiver detects the travel position of the vehicle based on the received radio wave, starts charging when the vehicle enters a charging area (for example, a specific city area), and ends when the vehicle leaves the charging area To do. At this time, when the vehicle is traveling in the billing area, the vehicle position, travel route, and travel distance are detected.

  When the vehicle enters the billing area, the in-vehicle device starts recording the travel route. When the vehicle exits the billing area, it calculates the travel distance from the travel route, charges the billing information, and sends the billing information to the billing center. To do.

In such a GPS road billing system, it is possible to eliminate a toll gate (gate facility) that was necessary in a conventional wireless toll collection system.
This GPS road billing system is intended to limit the traffic volume by imposing a charge on vehicles flowing into the city and to reduce congestion in the city.

FIG. 5 is an explanatory diagram showing an image of the GPS road billing system.
The vehicle 01 shown in FIG. 5 includes a vehicle-mounted device including a GPS receiver, a GPS antenna, and various sensors. This on-vehicle device is capable of estimating the position of the vehicle 01 every moment when the GPS receiver receives radio waves transmitted from a plurality of GPS satellites 02.
Further, when the radio wave transmitted from the GPS satellite 2 cannot be received and GPS positioning cannot be performed, for example, when the vehicle 01 is traveling in a tunnel, the travel distance and travel are performed using a self-supporting sensor (distance sensor or azimuth sensor). The current position information is estimated from the previous position information detected by the GPS receiver based on the travel distance and travel direction detected by a self-supporting sensor.

  The vehicle-mounted device mounted on the vehicle 01 obtains and records a route from the position estimation coordinates for billing when the vehicle 01 enters the billing area 03. When the vehicle 01 leaves the billing area 03, the travel distance is obtained from the route, billing is performed, and billing information is transmitted to the billing center 04.

  Next, the vehicle-mounted device will be described with reference to FIG. The vehicle-mounted device 10 includes a GPS receiver 11, an acceleration sensor 12, a vehicle speed sensor 13, a gyro 14, a position estimation unit 15, a map matching unit 16, a storage unit 17, and a billing processing unit 18. ing.

The GPS receiver 11 receives a radio wave transmitted from a GPS satellite via a GPS antenna (not shown), measures a position, and outputs position information.
The acceleration sensor 12 detects an acceleration along the traveling direction of the vehicle and outputs an acceleration signal.
The vehicle speed sensor 13 detects the vehicle speed of the vehicle and outputs a vehicle speed signal.
The gyro 14, which is an orientation sensor, detects the traveling direction of the vehicle and outputs a traveling direction signal.

  The position estimation unit 15 outputs position information measured by the GPS receiver 11 as estimated positions X and Y when positioning by the GPS receiver 11 is possible. The estimated positions X and Y are output at predetermined intervals.

On the other hand, when the positioning by the GPS receiver 11 becomes impossible, the position estimation unit 15 obtains the position based on the acceleration signal or the velocity signal and the traveling direction signal, and the obtained position is obtained. Are output as estimated positions X and Y.
That is, in order to make the acceleration sensor 12 and the speed sensor 13 function as a distance sensor, distance information obtained by integrating the acceleration signal twice, or distance information obtained by integrating the speed signal once, and the gyro 14 are obtained. The travel distance and travel direction are calculated based on the travel direction signal. Further, a relative movement position starting from the position immediately before the time when positioning cannot be performed by the GPS receiver 11 is obtained, and the relative movement position is output as estimated positions X and Y. The estimated positions X and Y are output at predetermined intervals.

The storage unit 17 stores map data. As the map data, only road information is stored, and information such as buildings and toll gates is not included.
As road information, in addition to position information along each road, it is set for each node (node) such as a route R (R1, R2, R3... Rn) set for each road (link) or an intersection or a corner. Nodes J (J1, J2, J3... Jn) are stored.

  The map matching unit 16 performs a map matching process using the estimated positions X and Y and the road information stored in the storage unit 17. That is, the position on the road closest to the positions indicated by the estimated positions X and Y is output as the map matching positions mX and mY. The map matching positions mX and mY are output at predetermined intervals.

  The charging processing unit 18 starts recording the map matching positions mX and mY output one after another from the map matching unit 16 when the vehicle enters the charging area. When the vehicle leaves the billing area, the travel distance is obtained based on the travel route obtained from the map matching positions mX and mY, and the billing information is transmitted to the billing center.

Note that the configuration of the vehicle-mounted device 10 shown in FIG. 6 is basically the same as the vehicle-mounted car navigation device that is currently widely used, and there are common points in the functions that are realized, but the following points are different.
1) In the car navigation system, because the purpose is driver navigation, the vehicle-mounted device for car navigation needs to display the position of the host vehicle on the map in real time.
On the other hand, it is important for the vehicle-mounted device 10 in the GPS road billing system to correctly determine the distance and route, and real-time display is not required.
2) Since the vehicle-mounted device 10 in the GPS road billing system is required to be reduced in cost for its purpose of use, the data capacity that can be held is limited to a small amount compared to the car navigation device. Therefore, it is desirable that only road information (position information along the road, route R, node J) is retained, while information necessary only for navigation display such as terrain, buildings, and landmarks is not retained.

Japanese Patent Laid-Open No. 61-56910

  Incidentally, the map matching unit 16 shown in FIG. 6 selects a position on the road closest to the estimated positions X and Y, and outputs it as the map matching positions mX and mY. However, when the calculation error of the estimated positions X and Y is large May select the wrong road (route R).

  For example, as shown in FIG. 7, it is assumed that there are a road R1 and a road R2, and the vehicle actually travels on the road R1. In FIG. 7, triangles (Δ) indicate estimated positions X and Y, black circles (●) indicate map matching positions mX and mY, and R1 and R2 indicate paths indicating roads. Further, the estimated positions X and Y and the map matching positions mX and mY indicate that data having a larger number is later in time (data that is new in time).

In the case of FIG. 7, since the estimated positions (X1, Y1), (X2, Y2), (X3, Y3) are close to the route R1, the map matching positions (mX1, mY1), (mX2, mY2), ( mX3, mY3) are located on the route R1 indicating the road on which the vehicle is actually traveling.
However, since the estimated positions (X4, Y4) and (X5, Y5) are away from the route R1 and close to the route R2, the map matching positions (mX4, mY4) and (mX5, mY5) are located on the route R2. End up. That is, although the vehicle is actually traveling on the road indicated by the route R1, it is erroneously determined that the vehicle is traveling on the road indicated by the route R2.

  As described above, if it is erroneously determined that the vehicle is traveling on a route different from the route on which the vehicle is actually traveling, a correct traveling route cannot be obtained, and accurate charging cannot be performed. There's a problem. For this reason, there is a demand for reducing the selection of the wrong road (route) and improving the accuracy for obtaining the correct route.

In the map matching unit in the car navigation device, as a technique for improving the performance of route determination, when passing through a toll gate, the position information is matched with the toll gate position on the map, or There is a method of recognizing surrounding buildings and correcting it by matching it with map information.
However, when such a method is adopted, information on the toll gate location, buildings, landmarks, etc. is stored in the storage unit, and building recognition and toll gate passage information for correcting the location in real time are stored. Sensors, processing devices, software, and the like necessary for recognition are required, resulting in a complicated system configuration and expensive equipment.
Therefore, it is not realistic to employ such a position correction technique for car navigation in an in-vehicle device for a GPS road billing system that requires a low price.

  An object of the present invention is to provide an in-vehicle device for detecting a traveling route that can accurately detect a route on which a vehicle travels while the system configuration is simple and inexpensive.

The configuration of the present invention for solving the above problems is as follows.
A GPS receiver for measuring position by receiving radio waves transmitted from GPS satellites and outputting position information;
A travel distance detecting means for outputting travel distance information indicating the travel distance of the vehicle;
Traveling direction detection means for outputting traveling direction information indicating the traveling direction of the vehicle;
When the position can be measured by the GPS receiver, the position indicated by the position information output from the GPS receiver is periodically output as the estimated position (X, Y), and when the position cannot be measured by the GPS receiver. A position estimation unit that obtains a movement position of the vehicle based on the movement distance information and the traveling direction information and periodically outputs the obtained position as an estimated position (X, Y);
A correcting unit that corrects the position of the estimated position (X, Y) and outputs the corrected position as a corrected position (cX, cY);
A storage unit storing road information having position information along the road as information;
A map that periodically outputs a position on the road closest to the position indicated by the correction position (cX, cY) as a map matching position (mX, mY) using the correction position (cX, cY) and the road information. A matching section,
The correction unit is
The corrected position (cX, cY) obtained by correcting the previous estimated position (X, Y) starting from the previous estimated position (X, Y) that is older in time than the latest estimated position (X, Y) ) To obtain a correction vector (V) whose end point is a map matching position (mX, mY) obtained by processing the map matching unit,
The previous estimated position (X, Y) that is temporally older than the latest estimated position (X, Y) and the corrected position (cX, cY) obtained by correcting the previous estimated position (X, Y). While determining whether the separation distance (d) between the map matching position (mX, mY) obtained by processing in the map matching unit is larger than a preset threshold distance (D),
From the start point to the end point when the latest estimated position (X, Y) is the start point and the latest estimated position (X, Y) is the end point with respect to the latest estimated position (X, Y). It is determined whether or not the relative angle (θ) formed by the estimated direction that is the direction and the direction in which the road closest to the previous estimated position (X, Y) extends is larger than a preset threshold angle (Θ). ,
If the separation distance (d) is greater than or equal to a preset threshold distance (D) or the relative angle (θ) is greater than or equal to a preset threshold angle (Θ), the latest estimated position (X, Y ) Is output as the correction position (cX, cY),
When the separation distance (d) is less than the preset threshold distance (D) and the relative angle (θ) is less than the preset threshold angle (Θ), the estimated position (X, A position obtained by moving the position indicated by Y) by the direction and distance indicated by the correction vector (V) is output as a correction position (cX, cY).
It is characterized by that.

The configuration of the present invention is as follows.
The vehicle-mounted device having the above-described configuration includes a charging processing unit that performs a charging process by determining a travel distance based on a travel route determined from a map matching position (mX, mY) output from the map matching unit. .

According to the present invention, when the latest estimated position is input, the latest estimated position is determined by the correction vector having the previous estimated position as the start point and the previous map matching position corresponding to the previous estimated position as the end point. Correction is performed to obtain a correction position.
In this way, since the latest estimated position is corrected based on the correction vector obtained based on the previous estimated position and map matching position to obtain the corrected position, the corrected position has less error, and the corrected position with less error is mapped. The map matching position obtained by the matching process improves the position accuracy. As a result, the travel route can be accurately determined.

  In addition, when the error becomes larger due to the correction, the correction is stopped, so that the travel route can be accurately determined.

  In addition, the storage unit of the on-vehicle device for detecting the travel route holds only road information and does not hold information necessary only for navigation display such as terrain, buildings, landmarks, etc. The data capacity can be reduced, the hardware and software can be simplified, and the cost can be reduced.

  The best mode for carrying out the present invention will be described below in detail based on examples.

FIG. 1 shows an in-vehicle device 100 for detecting a travel route according to a first embodiment of the present invention.
This in-vehicle device 100 includes a GPS receiver 111, an acceleration sensor 112, a vehicle speed sensor 113, a gyro 114, a position estimation unit 115, a map matching unit 116, a storage unit 117, a charging processing unit 118, and a correction. Part 200.

The GPS receiver 111 receives a radio wave transmitted from a GPS satellite via a GPS antenna (not shown), measures the position, and outputs position information.
The acceleration sensor 112 detects the acceleration along the traveling direction of the vehicle and outputs an acceleration signal.
The vehicle speed sensor 113 detects the vehicle speed of the vehicle and outputs a vehicle speed signal.
The gyro 114, which is an orientation sensor, detects the traveling direction of the vehicle and outputs a traveling direction signal.

  The position estimation unit 115 outputs position information measured by the GPS receiver 111 as estimated positions X and Y when positioning by the GPS receiver 111 is possible. The estimated positions X and Y are output at predetermined intervals.

On the other hand, when the positioning by the GPS receiver 111 becomes impossible, the position estimation unit 115 obtains the position based on the acceleration signal or the velocity signal and the traveling direction signal, and the obtained position is obtained. Are output as estimated positions X and Y.
That is, in order to cause the acceleration sensor 112 and the speed sensor 113 to function as distance sensors, the distance information obtained by integrating the acceleration signal twice, or the distance information obtained by integrating the speed signal once and the traveling direction signal. Based on the obtained traveling direction signal, the moving distance and the traveling direction are calculated. Further, a relative movement position starting from a position immediately before the time when positioning cannot be performed by the GPS receiver 111 is obtained, and the position is output as estimated positions X and Y. The estimated positions X and Y are output at predetermined intervals.

The correction unit 200 corrects the estimated positions X and Y and outputs corrected positions cX and cY. The correction positions cX and cY are output at predetermined intervals.
Although details of the correction processing by the correction unit 200 will be described later, by performing this correction, even if an error is included in the estimated positions X and Y, it is possible to accurately determine the route by correcting the position. Yes.

The storage unit 117 stores map data. As the map data, only road information S is stored, and information such as buildings and toll gates is not included.
As the road information S, in addition to the position information along each road, the route R (R1, R2, R3... Rn) set for each road to distinguish each road (link), intersections and branches A node J (J1, J2, J3... Jn) set for each node in order to distinguish nodes (nodes) such as points and corners is stored.

  In other words, the in-vehicle device 100 for detecting a travel route applied to the GPS road billing system is required to be reduced in cost for its purpose of use, so that the data capacity that can be held is limited to a small amount compared to the car navigation device. Only road information (position information along the road, route R, node J) is held, and information necessary only for navigation display such as terrain, buildings, and landmarks is not held. As a result, the data capacity is reduced and the hardware and software are simplified.

  The map matching unit 116 performs map matching processing using the correction positions cX and cY and the road information S stored in the storage unit 117. That is, the position on the road closest to the positions indicated by the correction positions cX and cY is output as the map matching positions mX and mY. The map matching positions mX and mY are output at predetermined intervals.

  The billing processing unit 118 starts recording the map matching positions mX and mY periodically output one after another from the map matching unit 116 when the vehicle enters the billing area. Then, when the vehicle leaves the billing area, the travel distance is obtained based on the travel route obtained from the map matching positions mX and mY, and the billing process is performed (the charge is calculated according to the travel distance). (Calculated fee) is sent to the billing center.

Here, the configuration of the functional part and the correction processing operation in the correction unit 200 will be described with reference to FIG. 2 which is a functional block diagram, and FIGS. 3 and 4 showing specific processing states.
The function of each functional unit will be described first based on FIG. 2, and then a specific example of correcting the estimated position based on FIGS. 3 and 4 will be described.

The correction unit 200 includes a memory 201, a correction necessity determination function unit 202, a correction vector calculation function unit 203, and a correction processing function unit 204.
Each of the functional units 202, 203, and 204 is a functional part that performs calculation / determination by software. In FIG. 2, these are shown in a block diagram.

The estimated positions X and Y output from the position estimation unit 115 are input to the memory 201, the correction necessity determination function unit 202, the correction vector calculation function unit 203, and the correction processing function unit 204.
The road information S stored in the storage unit 117 is input to the correction necessity determination function unit 203.
The map matching positions mX and mY output from the map matching unit 116 are input to the correction necessity determination function unit 202 and the correction vector calculation function unit 203.

The estimated positions X and Y periodically output from the position estimation unit 115 are input to the memory 201 and taken in.
Note that the memory 201 has a predetermined memory capacity, and when data of estimated positions X and Y exceeding the memory capacity is newly input, the data of the oldest estimated positions X and Y are erased. Thus, the data of the latest estimated positions X and Y that are newly input are stored.
In this example, the memory 201 can store at least the latest estimated positions X and Y and the previous estimated positions X and Y that are temporally older than the latest estimated positions X and Y.

When the latest estimated positions X and Y are input, the correction necessity determination function unit 202 takes in the previous estimated positions X and Y from the memory 201.
Further, the map matching positions mX and mY obtained by performing the map matching processing on the corrected positions cX and cY obtained by correcting the previous estimated positions X and Y (corresponding to the previous estimated positions X and Y). The map matching position mX, mY) and the road information S from the storage unit 117.

First, the correction necessity determination function unit 202 makes the following two determinations (1) and (2).
(1) Whether or not the separation distance d between the previous estimated positions X and Y and the map matching positions mX and mY corresponding to the previous estimated positions X and Y is greater than a preset threshold distance D. judge.
(2) An estimated direction that is a direction from the start point to the end point when the previous estimated position X, Y is the starting point and the latest estimated position X, Y is the end point, and the closest to the previous estimated position X, Y It is determined whether or not the relative angle θ formed with the direction in which the road extends is larger than a preset threshold angle Θ.
The “direction in which the road extends” is determined from the road information S.

The correction necessity determination function unit 202
(A) When the determination of either (1) or (2) is established, that is, the separation distance d is greater than or equal to a preset threshold distance D, or the relative angle θ is a preset threshold angle If it is greater than or equal to Θ, it is determined that correction is unnecessary.
(B) When both (1) and (2) are established, that is, the separation distance d is less than the preset threshold distance D, and the relative angle θ is less than the preset threshold angle Θ. In this case, it is determined that correction is necessary.

When the latest estimated positions X and Y are input, the correction vector calculation function unit 203 fetches the previous estimated positions X and Y from the memory 201.
Further, the map matching positions mX and mY obtained by performing the map matching processing on the corrected positions cX and cY obtained by correcting the previous estimated positions X and Y (corresponding to the previous estimated positions X and Y). Captured map matching position mX, mY)

  Then, when the correction vector determination function unit 202 determines that correction is necessary, the correction vector calculation function unit 203 uses the previous estimated positions X and Y as the starting points and maps corresponding to the previous estimated positions X and Y. A correction vector V having the matching positions mX and mY as end points is calculated.

When the latest estimated positions X and Y are input, the correction processing function unit 204 performs the following processing.
(A) When the correction necessity determination function unit 202 determines that the correction is unnecessary, the positions indicated by the latest estimated positions X and Y are directly output as the correction positions cX and cY.
(B) When the correction necessity determination function unit 202 determines that correction is necessary, the position indicated by the latest estimated positions X and Y is corrected by the correction vector V calculated by the correction vector calculation function unit 203. To do. Specifically, the positions indicated by the latest estimated positions X, Y are moved by the direction and distance indicated by the correction vector V, and are output as correction positions cX, cY.

Next, a specific example in which the correction unit 200 performs correction according to the estimated positions X and Y will be described with reference to FIGS. 3 and 4.
In the example of FIGS. 3 and 4, there are a road of the route R1 and a road of the route R2. In the example of FIG. 3, the vehicle actually travels on the road of the route R1, and in the example of FIG. Is actually traveling on the road R2.
3 and 4, triangles (Δ) indicate estimated positions X and Y, black circles (●) indicate map matching positions mX and mY, and squares (□) indicate correction positions cX and cY.
Further, the estimated positions X and Y, the map matching positions mX and mY, and the correction positions cX and cY indicate that the more subscripts, the later the data (temporally new data).

  The correction operation repeats the correction process according to a predetermined procedure every time the latest estimated positions X and Y are input to the correction unit 200. Therefore, in the following description, the estimated positions X3 and Y3 are input to the correction unit 200. The operation after the point in time is described.

The example of FIG. 3 will be described.
The operation of the correction unit 200 when the estimated positions X3 and Y3 are input to the correction unit 200 is as follows.

The correction necessity determination function unit 202
(1) The separation distance d2 between the estimated positions X2, Y2 and the map matching positions mX2, mY2 is not greater than a preset threshold distance D,
(2) The angle θ formed by the estimated direction starting from the estimated positions X2 and Y2 and ending at the estimated positions X3 and Y3 and the direction in which the route (road) R1 closest to the estimated positions X2 and Y2 extends is set in advance. Not greater than the threshold angle Θ,
It is determined that correction is necessary from the determination result.

  The correction vector calculation function unit 203 calculates a correction vector V2 having the estimated positions X2 and Y2 as start points and the map matching positions mX2 and mY2 as end points.

  The correction processing function unit 204 corrects the estimated positions X3 and Y3 with the correction vector V2 because the correction necessity determination function unit 202 determines that correction is necessary. That is, the positions obtained by moving the estimated positions X3 and Y3 by the distance and the direction indicated by the correction vector V2 are output as the corrected positions cX3 and cY3.

  Since the correction positions cX3 and cY3 are close to the route R1, the map matching positions mX3 and mY3 subjected to the map matching process by the map matching unit 116 are located on the route R1. As a result, even if the position accuracy of the estimated positions X3, Y3 is poor, the position accuracy of the map matching positions mX3, mY3 can be improved by correcting the position to the correction positions cX3, cY3 with higher accuracy. It is.

  The operation of the correction unit 200 when the estimated positions X4 and Y4 are input to the correction unit 200 is as follows.

The correction necessity determination function unit 202
(1) The separation distance d3 between the estimated positions X3 and Y3 and the map matching positions mX3 and mY3 is not greater than a preset threshold distance D,
(2) An angle θ formed by an estimated direction starting from the estimated positions X3 and Y3 and having the estimated positions X4 and Y4 as an end point and a direction in which the route (road) R1 closest to the estimated positions X3 and Y3 extends is set in advance. Not greater than the threshold angle Θ,
It is determined that correction is necessary from the determination result.

  The correction vector calculation function unit 203 calculates a correction vector V3 having the estimated positions X3 and Y3 as the start point and the map matching positions mX3 and mY3 as the end point.

  The correction processing function unit 204 corrects the estimated positions X4 and Y4 with the correction vector V3 because the correction necessity determination function unit 202 determines that correction is necessary. That is, the positions obtained by moving the positions indicated by the estimated positions X4 and Y4 by the distance and the direction indicated by the correction vector V3 are output as the correction positions cX4 and cY4.

  Since the correction positions cX4 and cY4 are close to the route R1, the map matching positions mX4 and mY4 subjected to the map matching process by the map matching unit 116 are located on the route R1. As a result, even if the position accuracy of the estimated positions X4 and Y4 is poor, the position accuracy of the map matching positions mX4 and mY4 can be improved by correcting the position to the correction positions cX4 and cY4 with higher accuracy. It is.

  The operation of the correction unit 200 when the estimated positions X5 and Y5 are input to the correction unit 200 is as follows.

The correction necessity determination function unit 202
(1) The separation distance d4 between the estimated positions X4 and Y4 and the map matching positions mX4 and mY4 is not greater than a preset threshold distance D,
(2) An angle θ formed by an estimated direction starting from the estimated positions X4 and Y4 and having the estimated positions X5 and Y5 as an end point and a direction in which the route (road) R1 closest to the estimated positions X4 and Y4 extends is set in advance. Not greater than the threshold angle Θ,
It is determined that correction is necessary from the determination result.

  The correction vector calculation function unit 203 calculates a correction vector V4 having the estimated positions X4 and Y4 as the start points and the map matching positions mX4 and mY4 as the end points.

  The correction processing function unit 204 corrects the estimated positions X5 and Y5 with the correction vector V4 because the correction necessity determination function unit 202 determines that correction is necessary. That is, the positions obtained by moving the estimated positions X5 and Y5 by the distance and the direction indicated by the correction vector V4 are output as the corrected positions cX5 and cY5.

  Since the correction positions cX5 and cY5 are close to the route R1, the map matching positions mX5 and mY5 subjected to the map matching processing by the map matching unit 116 are located on the route R1. As a result, even if the position accuracy of the estimated positions X5 and Y5 is poor, the position accuracy of the map matching positions mX5 and mY5 can be improved by correcting the position to the correction positions cX5 and cY5 with higher accuracy. It is.

  The operation of the correction unit 200 when the estimated positions X6 and Y6 are input to the correction unit 200 is as follows.

The correction necessity determination function unit 202
(1) The separation distance d4 between the estimated positions X5 and Y5 and the map matching positions mX5 and mY5 is not greater than a preset threshold distance D,
(2) An angle θ formed by an estimated direction starting from the estimated positions X5 and Y5 and having the estimated positions X6 and Y6 as an end point and a direction in which the route (road) R1 closest to the estimated positions X5 and Y5 extends is set in advance. Not greater than the threshold angle Θ,
It is determined that correction is necessary from the determination result.

  The correction vector calculation function unit 203 calculates a correction vector V5 having the estimated positions X5 and Y5 as the start points and the map matching positions mX5 and mY5 as the end points.

  The correction processing function unit 204 corrects the estimated positions X6 and Y6 with the correction vector V5 because the correction necessity determination function unit 202 determines that correction is necessary. That is, the positions obtained by moving the positions indicated by the estimated positions X6 and Y6 by the distance and the direction indicated by the correction vector V5 are output as the correction positions cX6 and cY6.

  Since the correction positions cX6 and cY6 are close to the route R1, the map matching positions mX6 and mY6 subjected to the map matching processing by the map matching unit 116 are located on the route R1. As a result, even if the position accuracy of the estimated positions X6 and Y6 is poor, the position accuracy of the map matching positions mX6 and mY6 can be improved by correcting the position to the correction positions cX6 and cY6 with higher accuracy. It is.

  After all, in the example of FIG. 3, even though the vehicle is traveling on the route R1, even if the estimated positions X and Y are separated from the route R1 due to an error, the corrected position cX after the position correction is performed. , CY are close to the path R1, the map matching positions mX, mY obtained by performing the map matching process on the correction positions cX, cY can be accurately positioned on the path R1, and the path can be accurately determined.

Next, the example of FIG. 4 will be described.
The operation of the correction unit 200 when the estimated positions X3 and Y3 are input to the correction unit 200 is as follows.

The correction necessity determination function unit 202
(1) The separation distance d2 between the estimated positions X2, Y2 and the map matching positions mX2, mY2 is not greater than a preset threshold distance D,
(2) The angle θ formed by the estimated direction starting from the estimated positions X2 and Y2 and ending at the estimated positions X3 and Y3 and the direction in which the route (road) R1 closest to the estimated positions X2 and Y2 extends is set in advance. Not greater than the threshold angle Θ,
It is determined that correction is necessary from the determination result.

  The correction vector calculation function unit 203 calculates a correction vector V2 having the estimated positions X2 and Y2 as start points and the map matching positions mX2 and mY2 as end points.

  The correction processing function unit 204 corrects the estimated positions X3 and Y3 with the correction vector V2 because the correction necessity determination function unit 202 determines that correction is necessary. That is, the positions obtained by moving the estimated positions X3 and Y3 by the distance and the direction indicated by the correction vector V2 are output as the corrected positions cX3 and cY3.

  Since the correction positions cX3 and cY3 are close to the route R1, the map matching positions mX3 and mY3 subjected to the map matching process by the map matching unit 116 are located on the route R1.

  The operation of the correction unit 200 when the estimated positions X4 and Y4 are input to the correction unit 200 is as follows.

The correction necessity determination function unit 202
(1) The separation distance d3 between the estimated positions X3 and Y3 and the map matching positions mX3 and mY3 is not greater than a preset threshold distance D,
(2) An angle θ formed by an estimated direction starting from the estimated positions X3 and Y3 and having the estimated positions X4 and Y4 as an end point and a direction in which the route (road) R1 closest to the estimated positions X3 and Y3 extends is set in advance. Not greater than the threshold angle Θ,
It is determined that correction is necessary from the determination result.

  The correction vector calculation function unit 203 calculates a correction vector V3 having the estimated positions X3 and Y3 as the start point and the map matching positions mX3 and mY3 as the end point.

  The correction processing function unit 204 corrects the estimated positions X4 and Y4 with the correction vector V3 because the correction necessity determination function unit 202 determines that correction is necessary. That is, the positions obtained by moving the positions indicated by the estimated positions X4 and Y4 by the distance and the direction indicated by the correction vector V3 are output as the correction positions cX4 and cY4.

  Since the correction positions cX4 and cY4 are close to the route R1, the map matching positions mX4 and mY4 subjected to the map matching process by the map matching unit 116 are located on the route R1.

  The operation of the correction unit 200 when the estimated positions X5 and Y5 are input to the correction unit 200 is as follows.

The correction necessity determination function unit 202
(1) A separation distance d4 between the estimated positions X4 and Y4 and the map matching positions mX4 and mY4 is larger than a preset threshold distance D,
(2) An angle θ formed by an estimated direction starting from the estimated positions X4 and Y4 and having the estimated positions X5 and Y5 as an end point and a direction in which the route (road) R1 closest to the estimated positions X4 and Y4 extends is set in advance. Greater than the threshold angle Θ,
From this determination result, it is determined that correction is unnecessary.

  The correction vector calculation function unit 203 does not calculate a correction vector because the correction necessity determination function unit 202 determines that correction is not necessary.

  Since the correction processing function unit 204 determines that the correction is unnecessary by the correction necessity determination function unit 202, the correction processing function unit 204 outputs the positions indicated by the estimated positions X5 and Y5 as the correction positions cX5 and cY5.

  Since the correction positions cX5 and cY5 are close to the path R2 instead of the path R1, the map matching positions mX5 and mY5 subjected to the map matching process by the map matching unit 116 are located on the path R2.

  The operation of the correction unit 200 when the estimated positions X6 and Y6 are input to the correction unit 200 is as follows.

The correction necessity determination function unit 202
(1) A separation distance d4 between the estimated positions X5 and Y5 and the map matching positions mX5 and mY5 is larger than a preset threshold distance D,
(2) An angle θ formed by an estimated direction starting from the estimated positions X5 and Y5 and having the estimated positions X6 and Y6 as an end point and a direction in which the route (road) R1 closest to the estimated positions X5 and Y5 extends is set in advance. Greater than the threshold angle Θ,
From this determination result, it is determined that correction is unnecessary.

  The correction vector calculation function unit 203 does not calculate a correction vector because the correction necessity determination function unit 202 determines that correction is not necessary.

  Since the correction processing function unit 204 determines that the correction is unnecessary by the correction necessity determination function unit 202, the correction processing function unit 204 outputs the positions indicated by the estimated positions X6 and Y6 as the correction positions cX6 and cY6.

  Since the correction positions cX6 and cY6 are close to the route R2, the map matching positions mX6 and mY6 subjected to the map matching process by the map matching unit 116 are located on the route R2.

After all, in the example of FIG. 4, although the vehicle is traveling on the route R2, initially the estimated position (X1, Y1) (X2, Y2) (X3, Y3) is close to the route R1 due to a calculation error or the like. Therefore, the corrected position (cX1, cY1) (cX2, cY2) (cX3, cY3) is output, and the map matching position (mX1, mY1) (mX2, mY2) (mX3, mY3) is on the path R1. Will be located.
However, when the calculation error decreases with time and the estimated position (X5, Y5) (X6, Y6) approaches the route R2 where the vehicle is actually traveling away from the route R1, the correction is performed. I try not to calculate.

  As a result, even if the calculation error of the estimated positions X and Y is initially large and the wrong route (R1) is selected, the calculation error of the estimated positions X and Y becomes smaller as time passes. By stopping the correction process, the map matching position can be accurately adjusted on the route (R2) on which the vehicle is traveling, and the accuracy of route determination can be improved.

In the example of FIG. 4, when the estimated positions (X5, Y5) and (X6, Y6) are input to the correction unit 200,
By the correction necessity determination function unit 202,
(1) The separation distances d4 and d5 are larger than a preset threshold distance D,
(2) The angle θ is larger than a preset threshold angle Θ.
It is determined that correction is unnecessary from this determination result,
When either one of the above (1) or (2) is determined, it is sufficient to determine that correction is unnecessary.

It is a block diagram which shows the onboard equipment for a driving | running route detection based on the Example of this invention. It is a block diagram which shows the correction | amendment part used for the onboard equipment of an Example. It is explanatory drawing which shows the specific correction | amendment operation | movement in a correction | amendment part. It is explanatory drawing which shows the specific correction | amendment operation | movement in a correction | amendment part. It is explanatory drawing which shows a GPS road billing system. It is a block diagram which shows the vehicle equipment for a driving | running route detection based on a prior art. It is explanatory drawing which shows the map matching method in a prior art.

Explanation of symbols

DESCRIPTION OF SYMBOLS 100 Onboard equipment 111 GPS receiver 112 Acceleration sensor 113 Vehicle speed sensor 114 Gyro 115 Position estimation part 116 Map matching part 117 Memory | storage part 118 Charge processing part 200 Correction part 201 Memory 202 Correction necessity determination function part 203 Correction vector calculation function part 204 Correction Processing function

Claims (2)

A GPS receiver for measuring position by receiving radio waves transmitted from GPS satellites and outputting position information;
A travel distance detecting means for outputting travel distance information indicating the travel distance of the vehicle;
Traveling direction detection means for outputting traveling direction information indicating the traveling direction of the vehicle;
When the position can be measured by the GPS receiver, the position indicated by the position information output from the GPS receiver is periodically output as the estimated position (X, Y), and when the position cannot be measured by the GPS receiver. A position estimation unit that obtains a movement position of the vehicle based on the movement distance information and the traveling direction information and periodically outputs the obtained position as an estimated position (X, Y);
A correcting unit that corrects the position of the estimated position (X, Y) and outputs the corrected position as a corrected position (cX, cY);
A storage unit storing road information having position information along the road as information;
A map that periodically outputs a position on the road closest to the position indicated by the correction position (cX, cY) as a map matching position (mX, mY) using the correction position (cX, cY) and the road information. A matching section,
The correction unit is
The corrected position (cX, cY) obtained by correcting the previous estimated position (X, Y) starting from the previous estimated position (X, Y) that is older in time than the latest estimated position (X, Y) ) To obtain a correction vector (V) whose end point is a map matching position (mX, mY) obtained by processing the map matching unit,
The previous estimated position (X, Y) that is temporally older than the latest estimated position (X, Y) and the corrected position (cX, cY) obtained by correcting the previous estimated position (X, Y). While determining whether the separation distance (d) between the map matching position (mX, mY) obtained by processing in the map matching unit is larger than a preset threshold distance (D),
From the start point to the end point when the latest estimated position (X, Y) is the start point and the latest estimated position (X, Y) is the end point with respect to the latest estimated position (X, Y). It is determined whether or not the relative angle (θ) formed by the estimated direction that is the direction and the direction in which the road closest to the previous estimated position (X, Y) extends is larger than a preset threshold angle (Θ). ,
If the separation distance (d) is greater than or equal to a preset threshold distance (D) or the relative angle (θ) is greater than or equal to a preset threshold angle (Θ), the latest estimated position (X, Y ) Is output as the correction position (cX, cY),
When the separation distance (d) is less than the preset threshold distance (D) and the relative angle (θ) is less than the preset threshold angle (Θ), the estimated position (X, A position obtained by moving the position indicated by Y) by the direction and distance indicated by the correction vector (V) is output as a correction position (cX, cY).
A vehicle-mounted device for detecting a traveling route. In claim 1 ,
An in-vehicle device for detecting a travel route, characterized by having a billing processing unit for obtaining a travel distance based on a travel route obtained from a map matching position (mX, mY) output from the map matching unit. .

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