JP2010003246A - Vehicle position information acquisition device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a vehicle position information acquisition device for acquiring a highly accurate positional relationship between vehicles even when using a GPS as a general positioning system. <P>SOLUTION: The vehicle position information acquisition device 1 for acquiring a positional relationship between a plurality of vehicles includes: an absolute position detection means for detecting the absolute position of each of the plurality of vehicles by using the GPS, and the positional relationship acquisition means for acquiring the positional relationship between the plurality of vehicles based on the absolute positions of the plurality of vehicles detected by the absolute position detection means. The absolute position detection means detects the absolute positions of the vehicles based on information from GPS satellites, which can be received by the plurality of vehicles in common. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a vehicle position information acquisition device that acquires a relative positional relationship between a plurality of vehicles.

In order to perform appropriate control in relation to other vehicles in a driving support device such as a collision prevention device, an inter-vehicle distance control device, or an automatic driving device, it is possible to obtain a highly accurate relative positional relationship between the own vehicle and the other vehicle. It becomes important. In the system described in Patent Document 1, in order to avoid contact between a plurality of moving bodies, each moving body detects its own absolute position with high accuracy and transmits it to the base station. Information (position, speed, traveling direction, etc.) of other moving bodies is transmitted, and the risk of contact with other moving bodies is determined in each moving body.
Japanese Patent Laid-Open No. 11-3499

  In order to determine the possibility of a collision between vehicles, it is necessary to grasp the relative positional relationship between the vehicles with high accuracy. Therefore, in the above system, it is necessary to use a high-precision GPS [Global Positioning System] (such as a GPS of a real-time kinematic positioning method) in order to detect a high-precision absolute position. In order to compare the positional relationship between the moving bodies, a highly accurate map having a common coordinate system for each moving body is also required. When such a high-accuracy GPS or map must be used, the cost is high, and there is a possibility that only some vehicles can be equipped. As a result, the accuracy of the relative position between the vehicles is reduced as a whole system.

  Therefore, an object of the present invention is to provide a vehicle position information acquisition device that can acquire a high-accuracy relative positional relationship between vehicles even when a general positioning GPS is used.

  A vehicle position information acquisition apparatus according to the present invention is a vehicle position information acquisition apparatus that acquires a relative positional relationship between a plurality of vehicles, and that detects absolute positions of the plurality of vehicles using GPS, respectively. And relative position relationship acquisition means for acquiring a relative position relationship between the plurality of vehicles based on the absolute positions of the plurality of vehicles respectively detected by the absolute position detection means. The absolute position of the vehicle is detected based on information from a group of GPS satellites that can be received in common.

  In this vehicle position information acquisition device, absolute position detection means using each piece of information from a GPS satellite group (at least the minimum number of GPS satellites necessary for obtaining the absolute position) that can be commonly received by a plurality of vehicles. To detect the absolute position of each vehicle. When absolute position positioning is performed with a common GPS satellite group, the error factor becomes common, and each positioning position (vehicle position) is affected by a substantially uniform error. Therefore, the same error is included in the absolute position obtained at each positioning position. Therefore, when the relative position is obtained from a plurality of absolute positions including the same error, the error is canceled out, and the relative position between the plurality of positioning positions becomes highly accurate. Therefore, in the vehicle position information acquisition device, the relative position relationship between the plurality of vehicles based on the absolute positions of the plurality of vehicles detected based on the information of the common GPS satellite group by the relative position relationship acquisition unit. To get. Thus, in the vehicle position information acquisition device, by obtaining the relative positional relationship between the vehicles from each absolute position of a plurality of vehicles obtained based on each information of the GPS satellite group that can be received in common, Even when a general positioning GPS is used, a highly accurate relative positional relationship between vehicles can be obtained.

  In the vehicle position information acquisition device of the present invention, when there are a plurality of vehicle groups that have acquired a relative positional relationship based on information from a GPS satellite group that can be received in common by a plurality of vehicles, a relative positional relationship acquisition unit Then, it is good also as a structure which acquires the relative positional relationship between the vehicles which belong to the said several vehicle group on the basis of the vehicle which belongs to all the vehicle groups of the said several vehicle group.

  In this vehicle position information acquisition device, when there are a plurality of vehicle groups that acquire a relative positional relationship based on information from GPS satellite groups that can be received in common, the relative positional relationship acquisition means Identify vehicles that are commonly included in the vehicle group, integrate the relative positional relationships of the plurality of vehicle groups based on the identified vehicle, and obtain the relative positional relationship between all the vehicles included in the plurality of vehicle groups. . As described above, in the vehicle position information acquisition device, when there are a plurality of vehicle groups in which a high-accuracy relative positional relationship is obtained, the relative positional relationship is integrated based on a common vehicle, so that a wider range can be obtained. A highly accurate relative positional relationship between the vehicles can be obtained.

  According to the present invention, the relative positional relationship between vehicles can be obtained by obtaining the relative positional relationship between vehicles using information of GPS satellite groups that can be received in common.

  Embodiments of a vehicle position information acquisition device according to the present invention will be described below with reference to the drawings.

  In the present embodiment, the vehicle position information acquisition device according to the present invention is applied to a vehicle position information acquisition device mounted on a vehicle. The vehicle position information acquisition apparatus according to the present embodiment measures an absolute position using GPS of a general positioning method, acquires a relative positional relationship between the host vehicle and another vehicle from the absolute position, and the relative position. Providing the relationship to driving assistance devices.

  Note that the vehicle position information acquisition device according to the present embodiment is a device serving as a host among the vehicle position information acquisition devices mounted on the respective vehicles constituting the relative positional relationship, and is a normal vehicle position information acquisition device. In addition to the processing that is performed in, host-specific processing is also performed. Which vehicle location information acquisition device (vehicle) is a host may be determined each time through communication between vehicles, may be determined with a predetermined vehicle, or selected according to a predetermined rule. May be.

  With reference to FIGS. 1-8, the vehicle position information acquisition apparatus 1 which concerns on this Embodiment is demonstrated. FIG. 1 is a configuration diagram of a vehicle position information acquisition apparatus according to the present embodiment. FIG. 2 is a table showing error factors of GPS positioning. FIG. 3 is an example of a GPS satellite that can be received by each vehicle. FIG. 4 is an example of a vehicle group capable of receiving a common GPS satellite group. FIG. 5 is a diagram showing a relative positional relationship obtained by a GPS satellite group common to the absolute positional relationship of the vehicle group in FIG. FIG. 6 is an example of two vehicle groups that can each receive a common GPS satellite group. FIG. 7 is a diagram showing a relative positional relationship obtained by a GPS satellite group common to the absolute positional relationship between the two vehicle groups in FIG. 6. FIG. 8 is a diagram showing a relative positional relationship between the two vehicle groups in FIG. 6 as a whole.

  The vehicle position information acquisition device 1 is obtained based on GPS satellite group information that can be received in common by the host vehicle and the other vehicle (one or a plurality of vehicles) in order to obtain a highly accurate relative positional relationship. The relative positional relationship is obtained from each absolute position. Furthermore, in the vehicle position information acquisition device 1, in order to obtain a relative positional relationship between vehicles in a wider range, a plurality of high-accuracy relative positional relationships based on the information of the common GPS satellite group are integrated to provide a wide range of vehicles between a large number of vehicles. The relative positional relationship of is obtained. For this purpose, the vehicle position information acquisition device 1 includes a GPS receiver 10, an inter-vehicle communication device 11, and an ECU [Electronic Control Unit] 20.

  In the present embodiment, the processing in the GPS receiver 10 and the ECU 20 corresponds to the absolute position detection means described in the claims, and the processing in the ECU 20 is the relative positional relationship acquisition means described in the claims. It corresponds to.

  The GPS receiver 10 includes a GPS antenna and the like, and is a receiver for receiving a signal from a GPS satellite. The GPS receiver 10 receives a GPS signal from each GPS satellite by the GPS antenna. The GPS receiver 10 demodulates the GPS signal and outputs the demodulated satellite information (for example, GPS satellite number, time information, orbit information, delay information due to the ionosphere and troposphere) to the ECU 20.

  FIG. 2 shows the main error factors of GPS positioning. The error sources include GPS satellite clock error, GPS satellite orbit error, GPS satellite placement, ionospheric delay error, troposphere delay error, vehicle There is noise in the surrounding environment (multipath, etc.) and GPS receiver. In the case of a GPS satellite clock error, the influence of single positioning is about 1 m, and if positioning is performed using the same GPS satellite information, the influence on positioning values in each vehicle is the same. In the case of a GPS satellite orbit error, the effect of single positioning is about 10 m. If positioning is performed using the same GPS satellite information, the effect on positioning values in each vehicle is the same. In the case of the arrangement of GPS satellites, the influence of single positioning varies depending on the relative positional relationship, and the influence on the positioning value varies depending on the relative positional relationship of the GPS satellite group. In the case of a delay error due to the ionosphere, the influence in single positioning is about 10 m, and the influence is almost the same within a limited geographical range. In the case of a delay error due to the troposphere, the influence in single positioning is about 2.5 m, and the influence is almost the same within a limited geographical range. In the case of the surrounding environment, the influence of the single positioning is 0.5 m or more, and the influence on the positioning value varies depending on the environment around the vehicle (positioning position). In the case of noise at the GPS receiver, the influence of single positioning is 0.4 m or more, and the influence on the positioning value varies depending on the performance of the GPS receiver.

  Among these error factors, GPS satellite clock error, GPS satellite orbit error, GPS satellite placement, ionospheric delay error, and tropospheric delay error are errors in each vehicle (each positioning position) included in the predetermined range. The factors are common, and each vehicle is affected by a substantially uniform error. For example, in the case of an ionosphere or troposphere, the predetermined range is a range that is similarly affected if it is within a range of several kilometers to 10 km. Therefore, when the absolute position is obtained using each satellite information from four or more of the same GPS satellite group in a plurality of vehicles within the predetermined range, the absolute position including the same error is obtained, respectively. The relative positional relationship between the plurality of vehicles derived from each absolute position is highly accurate with errors being offset.

  The inter-vehicle communication device 11 includes a communication antenna and the like, and is a wireless communication device for communicating between vehicles. The inter-vehicle communication device 11 transmits an inter-vehicle signal from the own vehicle to another vehicle existing within a predetermined distance by the communication antenna and receives an inter-vehicle signal from the other vehicle existing within the predetermined distance. The inter-vehicle communication device 11 modulates various information input from the ECU 20 and outputs the modulated inter-vehicle signal to the communication antenna. Further, the inter-vehicle communication device 11 demodulates the inter-vehicle signal from the other vehicle received by the communication antenna, and outputs the demodulated information on the other vehicle to the ECU 20.

  The ECU 20 is an electronic control unit including a CPU [Central Processing Unit], a ROM [Read Only Memory], a RAM [Random Access Memory], and the like, and comprehensively controls the vehicle position information acquisition apparatus 1. The ECU 20 receives information from the GPS receiver 10 and the inter-vehicle communication device 11 at regular time intervals. Then, the ECU 20 performs relative positional relationship specifying processing, relative positional relationship integration processing, and the like at regular time intervals. Further, when the ECU 20 can identify the relative positional relationship with the other vehicle, the ECU 20 transmits the relative positional relationship to a driving support device that requires the relative positional relationship with the other vehicle.

  The relative positional relationship specifying process will be described. As described above, when the absolute position is obtained using satellite information from GPS satellites common to a plurality of vehicles, the relative positional relationship between the plurality of vehicles can be obtained with high accuracy. Therefore, the other vehicle that needs a relative positional relationship is specified, a GPS satellite that can be received in common by the other vehicle and the own vehicle is selected, and the absolute position is determined using the satellite information of the common GPS satellite group. Each is obtained, and further the relative position is obtained from the absolute position.

  First, the ECU 20 obtains the number of a GPS satellite that can be received by each other vehicle for each other vehicle in the vicinity using inter-vehicle communication. Incidentally, in a normal vehicle position information acquisition device for vehicles other than the host, the number of receivable GPS satellites is notified to surrounding vehicles by inter-vehicle communication.

  The ECU 20 selects a partner other vehicle that requires a relative positional relationship from other nearby vehicles. As this selection method, for example, on the basis of a request from a driving support apparatus or the like that provides information on the relative positional relationship, about one vehicle (which may be a plurality of vehicles) that is most strongly related to the traveling of the host vehicle is used. select. Further, the ECU 20 searches for a common number based on the number of GPS satellites that can be received by the own vehicle and the number of GPS satellites that can be received by the other vehicle of the partner, and is shared by the own vehicle and the other vehicle of the partner. Select a receivable GPS satellite. In addition, when there are many common GPS satellites and four or more GPS satellites to be used for calculation are selected from among them, the error distribution of each GPS satellite is referred to and the GPS with a small error along the length direction of the road Select a satellite.

  In the example shown in FIG. 3, the host vehicle MV can receive five GPS satellites G1, G2, G3, G5, and G6, and the other vehicle OV that requires a relative positional relationship has five GPS satellites. G1, G3, G4, G5, and G6 can be received. Therefore, four GPS satellites G1, G3, G5, and G6 are selected as GPS satellites that can be received in common by the host vehicle MV and the other vehicle OV. The radio waves from the four GPS satellites G1, G3, G5, and G6 pass through the ionosphere and the troposphere having the same influence indicated by the symbol A and reach the host vehicle MV and the other vehicle OV.

  When there are four or more common GPS satellites, the ECU 20 notifies each other vehicle of the number of the common GPS satellites using inter-vehicle communication. Then, the ECU 20 uses the inter-vehicle communication to calculate the absolute position (X, Y, Z (altitude), t (time)) calculated based on each satellite information of the GPS satellite common to the other vehicle of the partner. Obtain from the opponent's other vehicle. By the way, in the normal vehicle position information acquisition device for vehicles other than the host, when the common GPS satellite group number is acquired from the host vehicle by inter-vehicle communication, the absolute position is calculated based on each satellite information of the GPS satellite group. Then, the calculated absolute position information is notified to the host vehicle or the like by inter-vehicle communication.

  The ECU 20 also calculates the absolute position (X, Y, Z, t) of the host vehicle based on each satellite information of the common GPS satellites. The ECU 20 notifies the other vehicle of the absolute position (X, Y, Z, t) of the subject vehicle using inter-vehicle communication. A conventional general method is applied to the absolute position calculation method using the satellite information of the four or more GPS satellites.

  Then, the ECU 20 calculates the relative position (direction and distance) of the partner other vehicle from the own vehicle based on the difference between the absolute position of the host vehicle and the absolute position of the partner other vehicle for each other vehicle of the partner. Incidentally, the normal vehicle position information acquisition device for vehicles other than the host also calculates the relative position (direction, distance) of the other vehicle from the vehicle by the same calculation. Thereby, in a plurality of vehicle groups including the own vehicle, a relative positional relationship between the vehicles is obtained for each vehicle.

  Furthermore, when the absolute position accuracy is also required, the ECU 20 selects a vehicle having the smallest DOP [Dilution Of Precision] among the own vehicle and the other vehicle of the opponent by GPS single positioning. Then, the ECU 20 translates the obtained relative positional relationship based on the absolute position of the selected vehicle with the highest accuracy in single positioning, and corrects the absolute position of the host vehicle and the absolute position of the other vehicle. . The value of DOP decreases as the number of GPS satellites used for calculating the absolute position increases, and as the altitude of the GPS satellite used for calculating the absolute position increases. The DOP is calculated for each vehicle and is obtained from each vehicle using inter-vehicle communication. Incidentally, even in a normal vehicle position information acquisition device for a vehicle other than the host, the same processing is performed when absolute position accuracy is required. Alternatively, information is acquired from the vehicle position information acquisition device 1 serving as a host by inter-vehicle communication.

  In the case of the example shown in FIG. 4, the absolute positions of the three vehicles V1, V2, and V3 are obtained based on the respective satellite information of the GPS satellite group A, and between the three vehicles V1, V2, and V3 from the absolute positions. The relative positional relationship of is obtained. FIG. 5 shows the true absolute positions T1, T2, T3 of the three vehicles V1, V2, V3 and the absolute positions R1, R2, R3 obtained based on the respective satellite information of the GPS satellite group A. ing. The absolute positions R1, R2, and R3 are separated from the true absolute positions T1, T2, and T3 due to the influence of errors when the GPS satellite group A is used, but are formed at the true absolute positions T1, T2, and T3. A relative positional relationship similar to the true relative positional relationship is formed.

  The relative positional relationship integration process will be described. Considering the global traffic environment, vehicles that can receive the same GPS satellite group in common are limited. In this case, there are a plurality of vehicle groups in which a high-accuracy relative positional relationship is obtained by the above-described relative positional relationship specifying process, but the error factor due to the GPS satellite group is not common among the plurality of vehicle groups. Therefore, it is not possible to ensure the accuracy of the relative positional relationship across the plurality of vehicle groups. So, relative position relationships (absolute positions included in each vehicle group) of each vehicle group are corrected based on the positions of the vehicles that are commonly included in multiple vehicle groups, and multiple relative position relationships are integrated. To do.

  As a method for determining the position of a vehicle common to a plurality of vehicle groups, for example, a vehicle having a minimum DOP in the single positioning is selected from all the vehicles in the plurality of vehicle groups, and the single positioning of the selected vehicle is performed. A method for determining the absolute position of a common vehicle by translating the relative positional relationship of a group of vehicles including the selected vehicle with respect to the absolute position of the satellite, and each satellite information of all GPS satellites receivable in the common vehicle There is a method of calculating the absolute position using.

  First, the ECU 20 acquires relative position information about each vehicle group and information about each vehicle obtained from a common GPS satellite group from other nearby vehicles using inter-vehicle communication. The relative position information includes the direction and distance between vehicles. The information on each vehicle includes absolute position information obtained from a common GPS satellite group, absolute position information obtained from all receivable GPS satellite groups, DOP in independent positioning, and the like. Incidentally, in a normal vehicle position information acquisition device for vehicles other than the host, the relative position information about the vehicle group to which the vehicle belongs and the information about the own vehicle are notified to surrounding vehicles by inter-vehicle communication.

  The ECU 20 selects a vehicle that is commonly included in all the vehicle groups from among all the vehicles included in the vehicle group corresponding to each of the collected GPS satellite groups. If there is no vehicle that is commonly included in all vehicle groups, the relative positional relationship cannot be integrated, and the process is terminated.

  The ECU 20 selects a vehicle having the smallest DOP in the single positioning from all the vehicles included in the vehicle group respectively corresponding to the plurality of GPS satellite groups that can be collected. Then, the ECU 20 translates the relative positional relationship of the vehicle group to which the selected vehicle belongs based on the absolute position of the selected vehicle in the single positioning, and the absolute value of the vehicle included in all the vehicle groups is included. Correct the position. Further, the ECU 20 translates the relative positional relationships of all the vehicle groups based on the corrected absolute positions of the commonly included vehicles, and corrects the absolute positions of all the vehicles. And ECU20 notifies each vehicle of the absolute position information (namely, relative position information between all the vehicles) about all the vehicles using inter-vehicle communication.

  In the case of the example shown in FIG. 6, a highly accurate relative positional relationship between the three vehicles V1, V2, and V3 is obtained based on each satellite information of the GPS satellite group A, and based on each satellite information of the GPS satellite group B. Thus, a highly accurate relative positional relationship between the three vehicles V3, V4, and V5 can be obtained. In the case of this example, in the vehicle groups V1, V2, V3 and the vehicle groups V3, V4, V5, the vehicle V3 is included in both vehicle groups.

  FIG. 7 shows true absolute positions T1, T2, and T3 of three vehicles V1, V2, and V3 and absolute positions RA1, RA2, and RA3 obtained based on each satellite information of the GPS satellite group A. Yes. Further, absolute absolute positions RB3, RB4, RB5 obtained based on the true absolute positions T3, T4, T5 of the three vehicles V3, V4, V5 and the respective satellite information of the GPS satellite group B are shown.

  FIG. 8 shows an absolute position RB3 obtained based on the relative positional relationship SA consisting of the absolute positions RA1, RA2 and RA3 obtained based on each satellite information of the GPS satellite group A and each satellite information of the GPS satellite group B. , RB4, RB5, and a relative positional relationship S integrated with the relative positional relationship SB. When the absolute position of the vehicle V3 common to the two vehicle groups is determined by a predetermined method, the relative position SA composed of the absolute positions RA1, RA2, and RA3 is translated using the absolute position R3 as a reference to move to the absolute position R1, R2 and R3 are obtained, and the relative position relationship SB composed of the absolute positions RB3, RB4 and RB5 is translated to obtain absolute positions R3, R4 and R5. As a result, the absolute positions R1, R2, R3, R4, and R5 are separated from the true absolute positions T1, T2, T3, T4, and T5, but formed at the true absolute positions T1, T2, T3, T4, and T5. A relative positional relationship S similar to the true relative positional relationship is formed.

  With reference to FIG. 1, the operation | movement in the vehicle position information acquisition apparatus 1 is demonstrated. In particular, the relative positional relationship specifying process in the ECU 20 will be described with reference to the flowchart of FIG. 9, and the relative positional relationship integration process will be described with reference to the flowchart of FIG. FIG. 9 is a flowchart showing a flow of relative positional relationship specifying processing in the ECU of FIG. FIG. 10 is a flowchart showing a flow of relative positional relationship integration processing in the ECU of FIG.

  The GPS receiver 10 receives a GPS signal from each GPS satellite with a GPS antenna, and outputs the received satellite information to the ECU 20. In the inter-vehicle communication device 11, various information is received from other vehicles around the own vehicle by a communication antenna at regular intervals, and each received information is output to the ECU 20. In the inter-vehicle communication device 11, various information from the ECU 20 is input, and the various information is transmitted to other nearby vehicles through the communication antenna.

  The ECU 20 repeats the following processing at regular intervals. First, the ECU 20 acquires the number of GPS satellites that can be received by other vehicles in the vicinity based on information from the inter-vehicle communication device 11 (S10).

  Based on the request from the driving support device or the like, the ECU 20 determines the other vehicle (one or a plurality of vehicles) that needs a relative positional relationship from other surrounding vehicles (S11). Then, the ECU 20 selects a GPS satellite that can be received in common by the partner other vehicle and the host vehicle based on the determined GPS satellite numbers that can be received by the partner other vehicle and the host vehicle (S12). . Further, the ECU 20 determines whether there are four or more GPS satellites that can be received in common (S13). If it is determined in S13 that there are less than four, the absolute position cannot be calculated for the common GPS satellite group, and thus the ECU 20 ends the current relative positional relationship specifying process.

  If it is determined in S13 that there are four or more, the ECU 20 notifies the inter-vehicle communication device 11 of the four or more GPS satellites in order to notify the other vehicle of the other party of the number of GPS satellites that can be received in common. Are output (S14). The inter-vehicle communication device 11 transmits each number of GPS satellites that can be commonly received together with information that can identify the other vehicle of the other party. In addition, when performing vehicle-to-vehicle communication, in order to identify each vehicle, the identification number of each vehicle is also transmitted / received.

  Further, the ECU 20 calculates the absolute position of the host vehicle based on each satellite information of common GPS satellites (S15). Then, the ECU 20 outputs the calculated absolute position of the own vehicle to the inter-vehicle communication device 11 in order to notify the other vehicle of the opponent of the absolute position of the own vehicle (S16). The inter-vehicle communication device 11 transmits the absolute position of the host vehicle together with information that can identify the other vehicle of the partner. In addition, the ECU 20 acquires the absolute position of the other vehicle of the other party based on information from the inter-vehicle communication device 11 (S17). Then, the ECU 20 calculates the relative position (direction, distance) of the other vehicle from the absolute position of the own vehicle and the absolute position of the other vehicle for each other vehicle of the opponent (S18).

  Further, the ECU 20 determines whether or not the absolute position accuracy is also required based on a request from the driving support device or the like (S19). If it is determined in S19 that the accuracy of the absolute position is not necessary, the ECU 20 ends the current relative positional relationship specifying process.

  If it is determined in S19 that the accuracy of the absolute position is also necessary, the ECU 20 selects a vehicle having the smallest DOP in the single positioning from all the vehicles for which the relative positional relationship is obtained, and the absolute position in the single positioning of the vehicle is selected. Using the position as a reference, the relative positional relationship is translated, the absolute position of the host vehicle and the absolute position of the other vehicle are corrected, and the current relative positional relationship specifying process is terminated (S20).

  When the relative positional relationship of the vehicle group including the host vehicle is specified, the ECU 20 uses the information from the inter-vehicle communication device 11 to determine the relative position information of each vehicle group obtained by each GPS satellite group from other nearby vehicles. Information on each vehicle is acquired (S30).

  When the relative position information of other vehicle groups can be acquired in addition to the vehicle group including the host vehicle, the ECU 20 selects vehicles included in all the vehicle groups in the vehicle groups respectively corresponding to the plurality of GPS satellite groups. Specify (S31). Then, the ECU 20 determines whether there is a vehicle common to all vehicle groups (S32). When it is determined in S32 that there is no common vehicle, the ECU 20 ends the current relative positional relationship integration process.

  If it is determined in S32 that there is a common vehicle, the ECU 20 selects a vehicle having the smallest DOP in the single positioning from all the vehicles included in the plurality of vehicle groups (S33). Using the absolute position of the selected vehicle in single positioning as a reference, the relative positional relationship of the vehicle group to which the vehicle belongs is translated to correct the absolute position of the vehicle common to all the vehicle groups (S33).

  Further, the ECU 20 translates the relative positional relationships of all the vehicle groups based on the corrected absolute positions of the vehicles common to all the vehicle groups, and the absolute positions of all the vehicles (and thus between all the vehicles). Relative position relationship) is corrected (S34). Then, in order to notify the corrected absolute position (relative position), the ECU 20 outputs the calculated absolute position (relative position) of each vehicle to the inter-vehicle communication device 11 and performs the relative position relationship integration process this time. The process ends (S35). The inter-vehicle communication device 11 transmits the absolute position (relative position) of each vehicle together with information that can identify each vehicle.

  According to this vehicle position information acquisition device 1, by obtaining the relative position between the vehicles from the absolute positions of a plurality of vehicles respectively obtained based on each satellite information of the GPS satellite group that can be received in common, Even when a general positioning method GPS is used, a highly accurate relative positional relationship between vehicles can be obtained.

  Furthermore, according to the vehicle position information acquisition apparatus 1, when there are a plurality of vehicle groups from which a highly accurate relative position is obtained based on a GPS satellite group that can be received in common, a vehicle that is common to all the vehicle groups. By integrating the relative positional relationship with reference to the above, a highly accurate relative positional relationship between a wider range of vehicles can be obtained.

  As mentioned above, although embodiment which concerns on this invention was described, this invention is implemented in various forms, without being limited to the said embodiment.

  For example, in the present embodiment, the relative positional relationship is specified by a device mounted on each vehicle, but information from a GPS satellite received by each vehicle is acquired by a roadside device such as a base station to obtain the relative position. It is good also as a structure which identifies a relationship and distributes a relative positional relationship to each vehicle from the apparatus of the roadside. In addition, when there is a vehicle having this relative positional relationship specifying function and a vehicle not having this function, the relative positional relationship specified to the vehicle not having this function may be transmitted from the vehicle having this function.

  In this embodiment, the absolute position is calculated for each vehicle. However, satellite information received by each vehicle may be collected by the host, and the absolute positions of all the vehicles may be calculated by the host.

  Further, in the present embodiment, an example of a method for selecting a vehicle that is commonly included in all the vehicle groups and a method for rearranging a plurality of relative positional relationships based on the common vehicle is shown. Other methods may be applied for the rearrangement method.

It is a block diagram of the vehicle position information acquisition apparatus which concerns on this Embodiment. It is a table | surface which shows the error factor of GPS positioning. It is an example of the GPS satellite which can be received by each vehicle. It is an example of a vehicle group that can receive a common GPS satellite group. FIG. 5 is a diagram showing a relative positional relationship obtained by a GPS satellite group common to the absolute position of the vehicle group in FIG. 4. It is an example of two vehicle groups which can each receive a common GPS satellite group. It is a figure which shows the relative positional relationship calculated | required by the GPS satellite group in common with the absolute position of two vehicle groups of FIG. It is a figure which shows the relative positional relationship of the whole two vehicle groups of FIG. It is a flowchart which shows the flow of the relative positional relationship specific process in ECU of FIG. It is a flowchart which shows the flow of the relative positional relationship integration process in ECU of FIG.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 1 ... Vehicle position information acquisition apparatus, 10 ... GPS receiver, 11 ... Inter-vehicle communication device, 20 ... ECU

Claims (2)

A vehicle position information acquisition device that acquires a relative positional relationship between a plurality of vehicles,
Absolute position detecting means for detecting the absolute positions of a plurality of vehicles using GPS,
A relative positional relationship acquisition unit configured to acquire a relative positional relationship between the plurality of vehicles based on the absolute positions of the plurality of vehicles respectively detected by the absolute position detection unit;
The absolute position detection means detects the absolute position of a vehicle based on information from a GPS satellite group that can be received in common by a plurality of vehicles.   When there are a plurality of vehicle groups that have acquired a relative positional relationship based on information from GPS satellite groups that can be received in common by a plurality of vehicles, the relative positional relationship acquisition unit may include all of the plurality of vehicle groups. 2. The vehicle position information acquisition apparatus according to claim 1, wherein a relative positional relationship between vehicles belonging to the plurality of vehicle groups is acquired with reference to vehicles belonging to the vehicle group.

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