JP2001067588A - Vehicle position detection device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To always and precisely detect the lateral direction position of a vehicle even if the characteristic of a magnetic marker generation magnetic field changes in terms of time and position by deciding the lateral direction position in the road of a vehicle by means of considering correction information corresponding to a characteristic that the generation magnetic field of a magnetic marker installed on the road changes. SOLUTION: Respective detection signals from a magnetic sensor 12 and a temperature sensor 14 are supplied to a control unit ECU 10. Reference characteristic information showing the characteristic of the generation magnetic field of a magnetic marker, a reference map showing the magnetic flux density distribution of the magnetic field generated from the magnetic marker, for example, is stored in a memory unit 25. A correction coefficient k(T) map based on the temperature dependency of magnetic flux density distribution is stored in the memory unit 25. When a detection temperature is obtained, a correction coefficient k(T) corresponding to the detection temperature T is decided from the correction coefficient k(T). The lateral direction position on the road of the vehicle is operated based on the correction coefficient k(T).

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a vehicle position detecting device for detecting a position (lateral position) of a vehicle in a width direction of a road, and more particularly, to a vehicle provided with a magnetic field from a magnetic marker laid on the road. And a vehicle position detecting device that detects a lateral position of the vehicle based on the detected magnetic field.

[0002]

2. Description of the Related Art Conventionally, there has been proposed an automatic driving vehicle that performs steering control so as to follow a predetermined course set on a road. In such an automatic driving vehicle, the position (lateral position) of the vehicle in the width direction of the road is always detected, and steering control is performed based on the detected position so that the vehicle does not deviate from the predetermined course. I have to.

A vehicle position detecting device mounted on such an automatic driving vehicle includes a magnetic sensor for detecting a magnetic field from a magnetic marker laid at a predetermined interval on the predetermined course. The strength of the magnetic field generated from each magnetic marker laid on the course changes according to the distance from the magnetic marker. From this, the vehicle position detection device,
Furthermore, reference characteristic information indicating the characteristics of the magnetic field generated by the magnetic marker, for example, a reference map indicating the relationship between the distance and the magnetic field strength is provided, and the distance corresponding to the magnetic field strength detected by the magnetic sensor is determined by the reference map. Is required. Then, the lateral position of the vehicle is calculated based on the obtained distance.

[0004] Reference characteristic information (for example, a reference map) representing the characteristic of the magnetic field generated by the magnetic marker provided in such a vehicle position detecting device is fixedly determined.

[0005]

The characteristics of the magnetic field generated from each magnetic marker laid on a predetermined course as described above change according to the external environment. For example, the characteristics of the magnetic field generated from the magnetic marker change depending on the temperature of the magnetic marker. Further, when the road on which the magnetic marker is laid is, for example, a bridge, a magnetic field generated from the magnetic marker is affected by a steel frame constituting the bridge.

When it is necessary to change the shape of the magnetic marker depending on the structure of the road on which the magnetic marker is laid, the specification of the magnetic field generated may vary depending on the difference in the shape. For example, in the above-described bridge, since the depth of the road is smaller than that of a normal road, the thickness of the magnetic marker to be laid on the road in the bridge is smaller than the thickness of the magnetic marker to be laid on the normal road. There is a need. For this reason, the characteristics of the magnetic field generated from the magnetic marker laid on the road in the bridge and the characteristics of the magnetic field generated from the magnetic marker to be laid on the normal road may be different.

Further, magnetic markers have been improved, and magnetic markers laid on roads may be changed to new types of magnetic markers having better characteristics. In such a case, it takes much time to replace all magnetic markers laid on a long road with new types of magnetic markers.
For this reason, traffic on the road must be regulated for a long time in order to replace all magnetic markers laid on the road with new types of magnetic markers. On the other hand, if you give priority to vehicle traffic without regulating traffic for such a long time,
A magnetic marker laid on a long road has to be partially replaced with a new type of magnetic marker. In such a case, a situation in which an old type magnetic marker and a new type magnetic marker having different characteristics regarding the generated magnetic field are mixed on a long road may occur.

As described above, when the characteristics of the magnetic field generated from each magnetic marker change with time or position due to a change in the external environment or a mixture of magnetic markers of different types, the generation of the magnetic marker is In a conventional vehicle position detection device that is provided with fixed reference characteristic information representing the characteristics of a magnetic field,
It is difficult to always detect an accurate lateral position of a vehicle.

An object of the present invention is to provide a vehicle position detecting device which can always more accurately detect the lateral position of a vehicle even if the characteristics of the magnetic field generated by the magnetic marker change over time and position. To provide.

[0010]

According to the present invention, there is provided a magnetic field marker mounted on a vehicle and laid along a predetermined course on a road. In a vehicle position detecting device that detects a generated magnetic field and determines a lateral position on a road of the vehicle based on the reference characteristic information indicating the characteristic of the generated magnetic field of the magnetic marker and the detected magnetic field, Correction information acquisition means for acquiring correction information corresponding to the characteristics of the magnetic field generated by the magnetic marker laid on the road; and the correction information acquired by the correction information acquisition means, the reference characteristic information, and the detected magnetic field. And position calculating means for calculating a lateral position of the vehicle on the road based on the calculated position.

In such a vehicle position detecting device, even if the characteristics of the magnetic field generated by the magnetic marker laid on the road change temporally or positionally, the vehicle takes into account correction information corresponding to the changed characteristics. The lateral position on the road is determined. The correction information is for correcting any of the information used for calculating the lateral position of the vehicle by the position calculation means, as long as the information corresponds to the characteristic of the generated magnetic field of the magnetic marker laid on the road. For example, whether to correct the reference characteristic information or to correct the detected magnetic field, an operation is performed based on the reference characteristic information and the detected magnetic field. For correcting information related to the lateral position of the vehicle.

The reference characteristic information representing the characteristic of the magnetic field generated by the magnetic marker is the information representing the characteristic of the magnetic field generated by the magnetic marker, for example, representing the relationship between the distance and the generated magnetic field in a map format. The information may be an arithmetic expression representing the characteristic, or may be information in another format. The characteristic of the magnetic field generated by the magnetic marker laid on the road changes with its temperature. From the viewpoint of more accurately detecting the lateral position of the vehicle on the road in consideration of the temperature dependency of the characteristic of the magnetic field generated by the magnetic marker, the present invention provides the above-described aspect as described in claim 2. In the vehicle position detection device, the correction information acquisition means, based on temperature information acquisition means for acquiring temperature information corresponding to the temperature of the magnetic marker laid on the road, temperature information acquired by the temperature information acquisition means, And a temperature-dependent correction information determining means for determining correction information based on the temperature dependence of the characteristic of the magnetic field generated by the magnetic marker.

[0013] The temperature information acquiring means may acquire the temperature information of the magnetic marker from the outside through a road-to-vehicle communication radio or the like, or may acquire the temperature information corresponding to the temperature of the magnetic marker on the vehicle side. It may be. From this latter point of view, the present invention provides, in the vehicle position detecting device, the temperature information acquiring means according to claim 3, wherein the temperature information acquiring means corresponds to a temperature of a magnetic marker laid on the road on the road. It can be configured so as to have a temperature detecting means for detecting as the obtained temperature information.

In particular, when the external environment of a magnetic marker laid on a road or the type of the magnetic marker changes in position, correction information corresponding to the characteristic of the magnetic field generated by the magnetic marker installed at each position is provided on the vehicle side. From the viewpoint of easy acquisition, the present invention is configured such that, in the vehicle position detecting device, the correction information acquiring unit acquires the correction information from outside the vehicle. Can be.

The reference characteristic information representing the characteristics of the magnetic field generated by the magnetic marker can be expressed as the relationship between the distance from the magnetic marker and the generated magnetic field (for example, magnetic flux density) at that position. In such a case, from the viewpoint of providing one mode of determining the lateral position of the vehicle in consideration of the correction information, the present invention provides the above-described vehicle position detecting device. The reference characteristic information represents a relationship between a magnetic field generated from the magnetic marker and information corresponding to a distance from the magnetic marker, and the position calculating means calculates information corresponding to the distance corresponding to the detected magnetic field. A first means for obtaining based on the reference characteristic information, and a second means for correcting information corresponding to the distance obtained by the first means based on the correction information obtained by the correction information obtaining means. And means for obtaining the lateral position of the vehicle based on the information corresponding to the distance corrected by the correction calculation means.

The information corresponding to the distance from the magnetic marker, which represents the relationship between the magnetic marker and the generated magnetic field in the reference characteristic information, may be the distance itself from the magnetic marker.
The information may be a lateral position on a road or other information corresponding to the distance from the magnetic marker. Also,
In order to solve the above problems, the present invention detects a magnetic field generated from a magnetic field marker mounted on a vehicle and laid along a predetermined course on a road, as described in claim 6, In a vehicle position detecting device which determines a lateral position of a vehicle on a road based on reference characteristic information representing characteristics of a magnetic field generated by a magnetic marker and the detected magnetic field, a lateral position of the vehicle on a road is determined. Is configured to include a characteristic changing unit that changes reference characteristic information for determining the characteristic.

In such a vehicle position detecting device, it is possible to change the reference characteristic information indicating the characteristic of the magnetic field generated by the magnetic marker to be used for determining the lateral position of the vehicle.
By changing the reference characteristic information in this way, the reference characteristic information to be actually used for determining the lateral position of the vehicle is changed to the magnetic field generated by the magnetic marker actually laid on the road which changes in time or position. Characteristics can be approximated.

The characteristic changing means may change the reference characteristic information itself to new reference characteristic information or correct the reference characteristic information. In particular, from the viewpoint that there is no need to store reference characteristic information suitable for the characteristics of the generated magnetic field of a magnetic marker laid on a road that changes positionally or temporally in a road, the vehicle position detection device has the following features. As described in 7, the characteristic changing means has characteristic acquiring means for acquiring the reference characteristic information from outside the vehicle, and converts the reference characteristic information used for determining the lateral position of the vehicle to the characteristic. It can be configured to change to the reference characteristic information acquired by the acquisition means.

The characteristic acquisition means may be configured to include characteristic receiving means for receiving reference characteristic information wirelessly transmitted from outside the vehicle, for example. The present invention is based on the ninth aspect of the present invention. From the viewpoint that, when changing the reference characteristic information indicating the characteristic of the generated magnetic field of the magnetic marker to be used for detecting the lateral position of the vehicle, infrastructure outside the vehicle can be used as little as possible. As described, the characteristic changing unit includes a storage unit that stores a plurality of reference characteristic information corresponding to a plurality of types of magnetic markers, and a lateral direction of the vehicle based on the plurality of reference characteristic information stored in the storage unit. Characteristic selecting means for selecting reference characteristic information to be used for determining the position, wherein the reference characteristic information used for determining the lateral position of the vehicle is changed to information selected by the characteristic selecting means. Can be configured.

In such a vehicle position detecting device, reference characteristic information to be used for detecting the lateral position of the vehicle is selected by the characteristic selecting means from the plurality of reference characteristic information stored in the storage means. Therefore, there is no need to obtain reference characteristic information to be used for detecting the lateral position of the vehicle from outside the vehicle. The characteristic selecting means may be configured to select the reference characteristic information based on an instruction from an occupant of the vehicle. Further, the characteristic selecting means may be configured to select the reference information based on predetermined conditions such as the above-mentioned temperature condition and the condition of the traveling position of the vehicle. In particular, from the viewpoint that information representing the characteristic can be selected based on the condition of the traveling position of the vehicle, the present invention provides, in the vehicle position detecting device, The characteristic selecting means has a vehicle traveling position acquiring means for acquiring a traveling position of the vehicle, and the characteristic selecting means has a vehicle traveling position acquiring means for acquiring a traveling position of the vehicle. When the acquired travel position of the vehicle is within the laying area of a different type of magnetic marker, reference characteristic information corresponding to the laying area is selected from a plurality of pieces of reference characteristic information stored in the storage means. Can be configured.

In such a vehicle position detecting device, even if the characteristics of the magnetic field generated by the magnetic markers laid on the road are different in position, the characteristics of the magnetic field generated by the magnetic markers actually laid at the running position of the vehicle are different. , The lateral position of the vehicle can be detected. From the viewpoint that the change of the reference characteristic information used for detecting the lateral position of the vehicle can be instructed from outside the vehicle, the present invention provides:
According to an eleventh aspect of the present invention, in the vehicle position detecting device, the characteristic selecting unit acquires, from outside the vehicle, specification information that specifies reference characteristic information to be used for determining a lateral position of the vehicle. Having designated information acquisition means,
The reference characteristic information specified by the specification information obtained by the specification information obtaining means may be selected from a plurality of pieces of reference characteristic information stored in the storage means.

In such a vehicle position detecting device, if the specified information is sent from the road to the vehicle at each point where the characteristics of the magnetic field generated by the magnetic mark change, the generation of the magnetic marker actually laid The lateral position of the vehicle can be detected using the reference characteristic information indicating the characteristic of the magnetic field. The specified information obtaining means may obtain the specified information from outside the vehicle by road-to-vehicle communication, or may obtain the specified information by including the specified information in a detected magnetic field.

Further, according to the present invention, a vehicle is provided in consideration of a change in reference characteristic information and correction information corresponding to the characteristic of a magnetic field generated by a magnetic marker laid on a road. By calculating the lateral position of the vehicle, an accurate lateral position of the vehicle can be detected.

[0024]

Embodiments of the present invention will be described below with reference to the drawings. A vehicle position detecting device according to an embodiment of the present invention is configured, for example, as shown in FIG. In FIG. 1, a vehicle position detecting device mounted on a vehicle includes a control unit (ECU) 10, a magnetic sensor 12, a temperature sensor 14, a manual switch 16, a communication unit 20, a memory unit 25, and an external storage device 35. I have. The magnetic sensor 10 detects a magnetic field generated from each magnetic marker laid at a predetermined interval along a predetermined course on a road. The temperature sensor 14 is installed, for example, at the bottom of the vehicle body and detects the outside air temperature on the road. The magnetic sensor 1
2 and the respective detection signals from the temperature sensor 14 are supplied to a control unit (ECU) 10.

The memory unit 25 stores reference characteristic information indicating characteristics of a magnetic field generated by the magnetic marker, for example, a reference map indicating a magnetic flux density distribution of a magnetic field generated from the magnetic marker. The magnetic field generated from each magnetic marker is
It has a vertical magnetic flux density distribution as shown in FIG. 2 and a horizontal magnetic flux density distribution as shown in FIG. This vertical magnetic flux density distribution represents a relationship yv = f (Gv) between the vertical magnetic flux density Gv and the distance yv from the magnetic marker. The horizontal magnetic flux density distribution is a relation y between the horizontal magnetic flux density Gh and the distance yh from the magnetic marker.
h = g (Gh). Therefore, the reference map representing the magnetic flux density distribution stored in the memory unit 25 includes the distance y from the magnetic marker, the vertical magnetic flux density Gv, and the horizontal magnetic flux density Gv.
and y = F (f (Gv), g (Gh)).
That is, the distance y from the magnetic marker corresponding to the vertical magnetic flux density Gv component and the horizontal magnetic flux density Gh component of the magnetic field detected by the magnetic sensor 12 can be specified by referring to the reference map.

The characteristics of the magnetic field generated by each magnetic marker fluctuate depending on the temperature. The reference map representing the magnetic flux density distribution is assumed to represent the characteristics at a predetermined temperature, for example, 25 ° C. The memory unit 25 further stores a correction coefficient k (T) map based on the temperature dependence of the magnetic flux density distribution. This correction coefficient k (T) map is used for the magnetic material (ferrite, NdFeB) used for the magnetic marker.
For example, it has a temperature characteristic Q as shown in FIG. That is, in the correction coefficient k (T) map, the correction coefficient value k (25 ° C.) becomes “1” at the predetermined temperature (for example, 25 ° C.) which is the temperature condition of the reference map, and the magnetic field generated from the magnetic marker Has a temperature characteristic Q corresponding to a change in the magnetic flux density distribution according to the temperature.

In the external storage device 35, for example, a CD-R
OM 36 is set. This CD-ROM 36 contains
Multiple types laid on the road (for example, for normal roads,
A plurality of reference maps representing the magnetic flux density distribution of the magnetic field generated from the magnetic marker of the bridge portion, the new type, the old type, etc.) are stored in association with the installation area. Note that each magnetic flux density distribution stored in the CD-ROM 36 is
It is a magnetic flux density distribution at the predetermined temperature (for example, 25 ° C.).

A navigation system 30 is connected to the control unit (ECU) 10, and the navigation system 30 provides the control unit (ECU) 10 with information on the traveling position of the vehicle. Hereinafter, the operation of the vehicle position detecting device configured as described above will be described. First, when the vehicle position detecting device configured as described above is activated when the vehicle travels on a road on which magnetic markers are laid at predetermined intervals along a predetermined course, the control unit (ECU) 10 , The position of the vehicle is acquired from the navigation system 30, and the reference map representing the magnetic flux density distribution of the magnetic markers laid in the area including the position is acquired from the external storage device 35. Then, the reference map acquired from the external storage device 35 is stored in the memory unit 25 as a reference map to be used for the lateral position calculation of the vehicle.

In this state, the control unit (ECU)
10 calculates the lateral position of the vehicle according to the procedure shown in FIG. 5, for example. This control unit (ECU) 10
The lateral position of the vehicle output from is used for steering control of the vehicle, for example. In FIG. 5, position information is acquired from the navigation system 30 (S1). This acquired position information is compared with the previously acquired position information (S2). Based on the comparison result, it is determined whether to change the reference map (S3). Whether or not the reference map needs to be changed is specifically determined based on whether or not the currently acquired position and the previously acquired position are included in the laying area of the same type of magnetic marker.

If it is determined that the reference map does not need to be changed (NO in S3), it is determined whether or not the vertical magnetic flux density Gv component of the magnetic field detected by the magnetic sensor 12 is equal to or higher than a predetermined level (step S3). S5). This is to determine whether the vehicle has approached a magnetic marker laid on the road. If the detected vertical magnetic flux density Gv component does not reach the predetermined value, the above-described processing (S1, S2, S
3, S5) is repeatedly executed.

If it is determined that the detected vertical magnetic flux density Gv component has exceeded a predetermined value (YES in S5S), the vehicle approaches the magnetic marker, and if the vertical magnetic flux density Gv component is further increased, the peak value is obtained. Is determined (S6). Then, when the vertical magnetic flux density Gv component detected when the vehicle comes closest to the magnetic marker reaches the peak value (YES in S6), the magnetic field detected from the magnetic sensor 12, specifically, the vertical magnetic flux density Gv The component and the horizontal magnetic flux density Gh component are obtained (S7).

Further, the detected temperature T from the temperature sensor 14 at that time is obtained (S7). When the detected temperature is obtained, the correction coefficient k stored in the memory unit 25 is calculated.
From the (T) map (see FIG. 4), a correction coefficient value k (T) corresponding to the detected temperature T is determined (S9). After that, referring to the reference map stored in the memory unit 25,
The distance y = F (f (Gv), g (Gh)) corresponding to the detected magnetic field (vertical magnetic flux density Gv, horizontal magnetic flux density Gh) is obtained. Further, a correction value yc = k (T) .F (f (Gv), g (Gh)) is calculated on the basis of the correction coefficient value k (T), and based on the correction value yc, the lateral direction of the vehicle on the road is calculated. The direction position is calculated (S10). The calculated lateral position of the vehicle is output to, for example, a steering control system (S1).
1). Thereafter, the processing described above (S1, S2, S3, S5,
S6 to S11) are repeatedly executed.

In the process where the above processing is repeatedly executed,
If it is determined that the reference map should be changed based on the position information acquired this time and the position information acquired last time (S
In 3), the reference map associated with the installation area including the traveling position of the vehicle specified by the position information acquired this time is read from the external storage device 35. Then, the read reference map is stored in the memory unit 25.
The reference map to be used for the calculation of the lateral position of the vehicle is changed (S4). Then, the detection magnetic field (vertical magnetic flux density v) from the magnetic sensor 12
Each time the peak value is detected (S5, S6), the same processing (S7 to S10) as the above-described processing is executed, and the lateral position of the vehicle is calculated.

As described above, by the processing in the control unit (ECU) 10 according to the procedure shown in FIG. 5, every time the type of the magnetic marker to be laid is changed in the course of traveling of the vehicle, the vehicle is controlled. The reference map used for the lateral position calculation is changed, and each time the distance y from the magnetic marker corresponding to the detected magnetic field is obtained with reference to this reference map, the distance y is used as the correction coefficient map k (T). Is corrected based on the correction coefficient corresponding to the detected temperature determined based on Then, the lateral position of the vehicle is calculated using the correction value yc. Therefore, even if the characteristic of the magnetic field generated by the magnetic marker laid on the road changes according to the type of the magnetic marker or changes due to the temperature, it is possible to detect a more accurate lateral position of the vehicle. Become.

If it is known in advance that a single type of magnetic marker is laid on the road, the processing from step S1 to step S4 is omitted in the processing according to the procedure shown in FIG. be able to. Further, as shown in FIG.
It has. The communication unit 20 performs data communication with communication equipment provided outside the vehicle. Using this communication unit 20, it is possible to receive designation of a reference map representing the characteristics of the generated magnetic field of the magnetic marker to be used for the above-described lateral position calculation of the vehicle. In this case, there is no need to acquire position information from the navigation system 30.

In the example where the reference map is designated by the communication unit 20, the road on which the vehicle travels is as shown in FIG. 7, for example. That is, the road is lane L
1 and L2. In particular, a magnetic marker is laid along a predetermined course set in the lane L2. A magnetic marker 50a of type A is laid in the area EA, a magnetic marker 50b of type B is laid in the area EB, and a magnetic marker 50c of type C is laid in the area EC. The beacon wave transmitting device 100 is installed at the boundary between the area EA and the area EB,
The beacon wave transmitting device 102
Is installed.

The beacon wave transmitting apparatus 100 transmits a beacon wave including the designation information of the type A magnetic marker 50a laid in the area EA. The beacon wave transmitting apparatus 102 transmits a beacon wave including the designation information of the type B magnetic marker 50b laid in the area EB.
The external storage device 35 in the vehicle position detection device mounted on the vehicle V running on such a road includes a reference map representing the characteristics of the generated magnetic field of the type A magnetic marker 50a, and the reference map of the generated magnetic field of the type B magnetic marker 50b. A reference map representing the characteristics and a reference map representing the characteristics of the magnetic field generated by the type C magnetic marker 50c are stored. The control unit (ECU) 10 in the vehicle position detecting device performs a process in accordance with, for example, a procedure shown in FIG.

While the vehicle V is traveling in the area EC, the type C magnetic marker 50 read from the external storage device 35 is used.
A reference map corresponding to the characteristic of the generated magnetic field c is stored in the memory unit 25. Then, as described above, every time the peak value of the magnetic field generated from the magnetic marker 50c is detected, the lateral position of the vehicle V is calculated with reference to the reference map stored in the memory unit 25.

In the process, as shown in FIG. 6, it is determined whether the communication unit 20 has received a beacon wave including the designation information of the reference map (S21). If the reception has not been made, steps S5 to S11 shown in FIG.
, A lateral position detection process P100 for calculating the lateral position of the vehicle V using the reference map stored in the memory unit 25 is repeatedly executed. Then, the vehicle V reaches the boundary between the area EC and the area EB, and the communication unit 2
When the beacon wave transmitted from the beacon wave transmission device 102 is received at 0 (YES in S21), the type B magnetic marker 50b included in the received beacon wave
Is obtained.

Then, based on the obtained designation information, the control unit (ECU) 10 reads out a reference map corresponding to the characteristics of the magnetic field generated by the type B magnetic marker 50b from the external storage device 35, and reads the reference map. Is stored in the memory unit 25 (S22). As a result, vehicle V
The reference map to be used in the calculation of the horizontal position is changed. Thereafter, in a state where the beacon wave including the designation information of the reference map is not received (NO in S21), the B-type magnetic marker newly stored in the memory unit 25 is used in the lateral position detection process P100 repeatedly executed. The lateral position of the vehicle V is calculated using the reference map corresponding to 50b.

Further, when the vehicle V advances, the area E in the lane L2
When reaching the boundary between B and the area EA, the communication unit 2
At 0, a beacon wave transmitted from beacon wave transmitting apparatus 100 is received (YES in S21). Then
A control unit (ECU) that has acquired the designation information of the type A magnetic marker 50a included in the received beacon wave
10 reads the reference map corresponding to the type A magnetic marker 50a from the external storage device 35 and stores it in the memory unit 25 in the same manner as described above, based on the acquired designation information (S22). As a result, the lateral position of the vehicle V that has entered the area EA from the area EB is the type A
Is calculated using a magnetic map corresponding to the characteristics of the magnetic field generated by the magnetic marker 50a (P100).

According to the above-described example, each time the vehicle arrives at the area where the magnetic marker of each type is laid, it is used for calculating the lateral position of the vehicle based on the designated information included in the received beacon wave. The reference map to be changed is changed to a reference map corresponding to the characteristic of the generated magnetic field of the magnetic marker laid in the area. Therefore, even if the type of the magnetic marker laid on the road is changed, the lateral position of the vehicle is always calculated using the reference map that matches the characteristics of the magnetic field generated by the changed magnetic marker.

The vehicle position detecting device is provided with a manual switch 16 connected to a control unit (ECU) 10 as shown in FIG. The manual switch 16 may be operated by a vehicle occupant to select a reference map to be used for calculating the lateral position of the vehicle. In this case, for example, when the vehicle approaches the bridge portion, the occupant operates the manual switch 16.
Is operated to specify a reference map that matches the characteristics of the generated magnetic field of the magnetic marker laid on the bridge. The specified reference map is read from the external storage device 35 and stored in the memory unit 25. Also, when the vehicle enters a normal road from the bridge, the occupant must manually switch the vehicle.
6 is operated to specify a reference map that matches the characteristics of the generated magnetic field of the magnetic marker laid on a normal road, the specified reference map is read from the external storage device 35 and stored in the memory unit 25. You.

In this case, even if the type of the magnetic marker laid on the road is changed in position, the manual switch 1
By the operation of 6, the reference map to be used for the calculation of the lateral position of the vehicle can be changed to a reference map that matches the characteristics of the magnetic field generated by the changed magnetic marker.
In each of the above-described examples, the reference map to be used for the calculation of the lateral position of the vehicle is changed to one that matches the characteristics of the magnetic field generated by the magnetic marker installed at the position where the vehicle travels. Is not limited to such an embodiment. For example, in a state where a reference map corresponding to the characteristics of the generated magnetic field of a predetermined type of magnetic marker is stored in the memory unit 25 as a master reference map, every time the type of the magnetic marker installed at the traveling position of the vehicle changes, The correction information based on the difference between the characteristic of the magnetic field generated by the magnetic marker and the characteristic of the magnetic field generated by the magnetic marker corresponding to the master reference map may be provided to the vehicle position detecting device. In this case, the lateral position of the vehicle is calculated based on the master reference map, the provided correction information, and the detected magnetic field.

The correction information is stored in the external storage device 35.
May be stored in association with the laying area of the magnetic marker corresponding to, and read from the external storage device 35 based on the detected position of the vehicle, or may be stored based on the designation information received by the communication unit 20. The information may be read from the external storage device 35. Further, the correction information is used to correct the information obtained from the master reference map or to correct the detected magnetic field from the magnetic sensor 12 to calculate the lateral position of the vehicle. To correct the information obtained in the process of
It may be for finally correcting the lateral position of the vehicle calculated from the master reference map and the detected magnetic field.

The reference map and the correction information may be received by the communication unit 20 from outside the vehicle. Further, the reference map, the correction information, the designation information for specifying the reference map and the correction information, etc. are received from communication equipment provided on the road (road-to-vehicle communication).
It is also possible to adopt a configuration in which reception is performed using the Internet, a navigation system using a mobile phone, a vehicle dispatch system, or the like.

Further, the reference map and the correction information include:
In addition to the configuration provided from the external storage device 35 to the control unit (ECU) 10, a storage medium (CD-ROM or DVD-ROM) storing map information of the navigation system
It can be stored and provided to the control unit (ECU) 10 from the navigation system together with the position information.

Further, in the above-described example, the reference map indicating the relationship between the magnetic field and the distance is used as the reference characteristic information indicating the characteristic of the magnetic field generated by the magnetic marker. However, an arithmetic expression (for example, y = F (f (Gv), g (Gh))) can be used as the reference characteristic information. In the above-described example, the correction coefficient k (T) map relating to the temperature correction is fixedly provided. However, when a plurality of types of magnetic markers having different temperature characteristics are laid on the road, the above-described reference map or the above-described reference map is used. Similarly to the correction information, the correction coefficient k (T) map can be changed according to the type of the magnetic marker installed at the position where the vehicle travels.

The temperature of the magnetic marker is directly measured and measured.
The measured temperature can be provided to the vehicle position detecting device via the communication unit 20 by road-vehicle communication. In the above example, the processing in step S9 and the correction coefficient k (T) map shown in FIG. 5 correspond to the correction information obtaining means, and the processing in step S10 is the position calculating means (first means, second means). Corresponding to The temperature sensor 14 corresponds to temperature information acquisition means (temperature detection means), and the processing in step S9 corresponds to temperature-dependent correction information determination means.

The processing in steps S1 to S4 shown in FIG. 5 corresponds to the characteristic changing means. The communication unit 20 corresponds to a characteristic acquiring unit (characteristic receiving unit) that acquires reference characteristic information from outside the vehicle. Further, the external storage device 35 corresponds to a storage unit, and the processing in steps S1 to S4 corresponds to a characteristic selection unit. Further, the manual switch 16 also corresponds to the characteristic selecting means.

The processing in step S1 corresponds to the vehicle travel position obtaining means, and the communication unit 20 corresponds to the specification information specifying means.

[0052]

As described above, according to the first to fifth aspects of the present invention, even if the characteristic of the magnetic field generated by the magnetic marker laid on the road changes temporally and positionally,
The lateral position of the vehicle on the road is determined in consideration of the correction information corresponding to the changed characteristic. As a result, the characteristics of the magnetic field generated by the magnetic marker laid on the road
Even if the position changes, the lateral position of the vehicle can always be detected more accurately.

According to the present invention, the reference characteristic information is changed, and the reference characteristic information to be actually used for determining the lateral position of the vehicle is temporally and temporally changed.
It is possible to approximate the characteristics of the magnetic field generated by the magnetic marker actually laid on the road that changes in position. As a result, even if the characteristics of the magnetic field generated by the magnetic marker change over time and position, the lateral position of the vehicle can always be detected more accurately.

[Brief description of the drawings]

FIG. 1 is a block diagram illustrating a configuration example of a vehicle position detection device according to an embodiment of the present invention.

FIG. 2 is a diagram illustrating an example of a vertical magnetic flux density distribution characteristic of a magnetic marker.

FIG. 3 is a diagram illustrating an example of a horizontal magnetic flux density distribution characteristic of a magnetic marker.

FIG. 4 is a diagram showing an example of a correction coefficient map.

FIG. 5 is a flowchart illustrating an example of a processing procedure in a control unit.

FIG. 6 is a flowchart illustrating another example of the procedure of the process in the control unit.

FIG. 7 is a diagram illustrating an example of a state of a road on which a vehicle equipped with the vehicle position detection device travels.

[Explanation of symbols]

 Reference Signs List 10 control unit (ECU) 12 magnetic sensor 14 temperature sensor 16 manual switch 20 communication unit 25 memory unit 30 navigation system 35 external storage device 36 CD-ROM 50a, 50b, 50c magnetic marker 100, 102 beacon wave transmitting device

Continuation of the front page F term (reference) 2F063 AA02 BA11 CA40 CB01 DA01 DA08 DA19 DB04 GA52 JA09 LA29 NA01 5H180 AA01 BB13 CC17 CC24 FF05 FF13 5H301 AA01 BB20 CC03 CC06 DD07 DD11 DD17 EE04 EE12 FF04 FF11 FF23 H12 Q12

Claims (16)

[Claims] A magnetic field generated from a magnetic marker mounted on a vehicle and laid along a predetermined course on a road is detected, and reference characteristic information indicating characteristics of a magnetic field generated by the magnetic marker and the detected magnetic field are detected. In a vehicle position detecting device configured to determine a lateral position of the vehicle on a road based on a magnetic field, correction information obtaining means for obtaining correction information corresponding to a characteristic of a generated magnetic field of a magnetic marker laid on the road, A vehicle position detection device having position calculation means for calculating a lateral position of the vehicle on a road based on the correction information acquired by the correction information acquisition means, the reference characteristic information, and the detected magnetic field. 2. The vehicle position detecting device according to claim 1, wherein said correction information obtaining means obtains temperature information corresponding to a temperature of a magnetic marker laid on a road; Based on the temperature information obtained
A vehicle position detecting device comprising: temperature-dependent correction information determining means for determining correction information based on temperature dependence of characteristics of a magnetic field generated by a magnetic marker. 3. The vehicle position detecting device according to claim 2, wherein said temperature information acquiring means has a temperature detecting means for detecting an outside air temperature of the vehicle as temperature information corresponding to a temperature of a magnetic marker laid on said road. Vehicle position detection device. 4. The vehicle position detecting device according to claim 1, wherein said correction information obtaining means obtains said correction information from outside of the vehicle. 5. The vehicle position detecting device according to claim 1, wherein the reference characteristic information represents a relationship between a magnetic field generated from a magnetic marker and information corresponding to a distance from the magnetic marker. Position calculating means for obtaining information corresponding to the distance corresponding to the detected magnetic field based on the reference characteristic information; and information corresponding to the distance obtained by the first means. And a second means for correcting based on the correction information obtained by the correction information obtaining means, and a side of the vehicle based on the information corresponding to the distance corrected by the second means. A vehicle position detecting device for obtaining a direction position. 6. A magnetic field generated from a magnetic marker mounted on a vehicle and laid along a predetermined course on a road is detected, and reference characteristic information indicating characteristics of a magnetic field generated by the magnetic marker and the detected characteristic information are detected. A vehicle position detection device that determines a lateral position of a vehicle on a road based on a magnetic field, wherein the vehicle includes a characteristic changing unit that changes reference characteristic information for determining a lateral position of the vehicle on a road. Position detection device. 7. The vehicle position detecting device according to claim 6, wherein said characteristic changing means has characteristic acquiring means for acquiring said reference characteristic information from outside of the vehicle, and is used for determining a lateral position of said vehicle. A vehicle position detecting device configured to change the reference characteristic information to be obtained to the reference characteristic information acquired by the characteristic acquisition means. 8. A vehicle position detecting device according to claim 7, wherein said characteristic acquiring means includes characteristic receiving means for receiving reference characteristic information wirelessly transmitted from outside the vehicle. 9. A vehicle position detecting device according to claim 6, wherein said characteristic change means stores a plurality of reference characteristic information corresponding to a plurality of types of magnetic markers, and a plurality of reference characteristic information stored in said storage means. Characteristic selecting means for selecting reference characteristic information to be used for determining the lateral position of the vehicle from the reference characteristic information of the vehicle. The characteristic selecting means uses the reference characteristic information used for determining the lateral position of the vehicle. A vehicle position detecting device configured to change the information to the information selected by the user. 10. The vehicle position detecting device according to claim 9, wherein said storage means stores a plurality of reference characteristic information in association with a laying area of a corresponding type of magnetic marker; Vehicle traveling position acquisition means for acquiring the traveling position of the vehicle, when the traveling position of the vehicle acquired by the vehicle traveling position acquisition means is within the laying area of different types of magnetic markers, the laying area A vehicle position detecting device which selects corresponding reference characteristic information from a plurality of reference characteristic information stored in the storage means. 11. A vehicle position detecting apparatus according to claim 9, wherein said characteristic selecting means obtains, from outside the vehicle, specification information for specifying reference characteristic information to be used for determining a lateral position of said vehicle. A vehicle position detection device having information acquisition means, wherein the reference characteristic information specified by the designation information acquired by the designation information acquisition means is selected from a plurality of pieces of reference characteristic information stored in the storage means; . 12. The vehicle position detecting device according to claim 6, wherein correction information obtaining means obtains correction information corresponding to a characteristic of a magnetic field generated by a magnetic marker laid on the road; A vehicle position detecting device comprising: a position calculating unit that calculates a lateral position of the vehicle on a road based on the correction information acquired by the unit, the reference characteristic information, and the detected magnetic field. 13. The vehicle position detecting device according to claim 12, wherein the correction information obtaining means obtains temperature information corresponding to a temperature of a magnetic marker laid on the road, and the temperature information obtaining means. Based on the temperature information obtained
A vehicle position detecting device comprising: temperature-dependent correction information determining means for determining correction information based on temperature dependence of characteristics of a magnetic field generated by a magnetic marker. 14. A vehicle position detecting device according to claim 13, wherein said temperature information acquiring means has a temperature detecting means for detecting an outside air temperature of the vehicle as temperature information corresponding to a temperature of a magnetic marker laid on said road. Vehicle position detection device. 15. The vehicle position detecting device according to claim 12, wherein said correction information obtaining means obtains said correction information from outside the vehicle. 16. The vehicle position detecting device according to claim 12, wherein the reference characteristic information represents a relationship between a magnetic field generated from a magnetic marker and information corresponding to a distance from the magnetic marker. Position calculating means for obtaining information corresponding to the distance corresponding to the detected magnetic field based on the reference characteristic information; and information corresponding to the distance obtained by the first means. And a second means for correcting based on the correction information obtained by the correction information obtaining means, and a side of the vehicle based on the information corresponding to the distance corrected by the second means. A vehicle position detecting device for obtaining a direction position.