JP2014085219A - Position detection device, position detection method and drive support device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a position detection device, a position detection method and a drive support device which can accurately detect a position of a vehicle by reducing the possibility of an error in a detected position of the vehicle.SOLUTION: A position detection device: calculates a shield section, on a travel route of a vehicle, where GPS signals transmitted from respective GPS satellites are shielded by a building existing along the travel route of the vehicle on the basis of positions of respective GPS satellites and three-dimensional map data; identifies points, as shield points, where received power of respective GPS signals obtained through a GPS receiver in the shield section becomes a predetermined threshold value or below; obtains positional relations, between an arbitrary base point among the plurality of identified shield points and other respective shield points, as predicted distances on the basis of the GPS signals and measured distances on the basis of detected values with respect to distances of the vehicle; and detects the base point, in forms of a position of the vehicle, which is determined to be reliable on the basis of a comparison result between the predicted values and the measured values corresponding to respective shield points.

Description

  The present invention relates to a position detection device, a position detection method, and a driving support device.

  Conventionally, a technique for detecting the position of a vehicle when a radio wave from a base station or a satellite is interrupted has been developed. For example, Patent Document 1 discloses a technique for detecting the position of a vehicle by detecting an area end of a radio wave transmitted from a base station. Further, in Patent Document 2, a GPS signal that is not shielded by the shielding object is determined as a coincidence signal of the satellite direction, and a reflection of the GPS signal shielded by the shielding object is determined as a mismatching signal of the satellite direction, and is corrected to the mismatch signal. A technique for detecting the position of a vehicle by adding a value is disclosed.

JP 2008-039688 A JP 2009-204421 A

  However, in the conventional technology (Patent Documents 1 and 2 etc.), for example, in a region where there is a building that can be a shield such as a building such as a high-rise building or a feature such as a tunnel, a radio wave from a GPS satellite is blocked or reflected. Since it occurs irregularly, a position error of the detected vehicle may occur. Therefore, in the prior art, there is room for further improvement in that the position of the vehicle is detected with high accuracy.

  The present invention has been made in view of the above circumstances, and is a position detection device and position detection capable of detecting the position of a vehicle with high accuracy by reducing the possibility of occurrence of a detected position error of the vehicle. It is an object to provide a method and a driving support device.

  The position detection device of the present invention receives a GPS signal transmitted from a plurality of GPS satellites, and acquires a received power of each GPS signal and a satellite position of each GPS satellite from the received GPS signal; A storage unit for storing three-dimensional map data including position information and shape information of the building, a satellite position of each GPS satellite acquired by the GPS receiver, and the three-dimensional unit stored in the storage unit Based on the map data, a shielding section calculation unit that calculates a shielding section in which a GPS signal transmitted from each GPS satellite is shielded by a building existing around the traveling path of the vehicle on the traveling path of the vehicle; A point where the received power of each GPS signal acquired by the GPS receiver is equal to or less than a predetermined threshold within the shielding interval calculated by the shielding interval calculation unit. A predicted position based on the GPS signal, a shielding point measuring unit that measures as a shielding point, and a positional relationship between an arbitrary base point and each other shielding point among a plurality of shielding points measured by the shielding point measuring unit, The shielding point of the base point determined to be highly reliable based on a comparison result between the predicted distance corresponding to each shielding point and the actually measured distance is obtained as an actually measured distance based on a detection value related to the distance of the vehicle. And a vehicle position detection unit that detects the position of the vehicle.

  In the position detection device, the vehicle position detection unit includes a comparison unit that obtains a difference between the predicted distance corresponding to each shielding point and the actually measured distance, and a shielding point of a difference that is equal to or less than a predetermined error based on the detection value. A reliability determination unit that determines that the set is highly reliable and that the shielding point that is larger than the predetermined error is an outlier and determines that the reliability is low, and the reliability determination unit determines that the reliability is high It is preferable to further include a vehicle position determination unit that calculates an average value of each shielding point included in the set and determines a point corresponding to the calculated average value as the position of the vehicle.

  In the position detection device, the vehicle position determination unit includes the GPS signal acquired by the GPS receiver among the shielding points included in the set determined to be high by the reliability determination unit. It is preferable that the average value is calculated by applying a weighted average to the shielded points where the received power is higher than the received power at the respective shielded points, and the received power is weighted.

  In the position detection device, the vehicle position determination unit includes the GPS signal acquired by the GPS receiver among the shielding points included in the set determined to be high by the reliability determination unit. The average value is calculated by applying a weighted average to the shielded points where the power change of the received power of the shielded power point changes more rapidly than the power change of the received power at each shielded point. Is preferred.

  In the position detection device, the three-dimensional map data further includes traveling environment information indicating an urban area or a suburb, the three-dimensional map data stored in the storage unit, and the GPS received by the GPS receiver. Based on the position of the vehicle based on the signal, it is determined whether the current driving environment is the city area or the suburbs, and if the current driving environment is determined to be the suburbs, the shielding section calculation unit, It is preferable to further include a shielding point measurement unit and a processing stop unit that stops the processing of the vehicle position detection unit.

  In the position detection device, a recovery point measurement unit that measures a point where the received power of each GPS signal acquired by the GPS receiver is greater than the predetermined threshold from a state equal to or less than the predetermined threshold, as a recovery point The vehicle position detection unit further includes a predicted distance based on the GPS signal based on the positional relationship between an arbitrary base point and each other recovery point among the plurality of recovery points measured by the recovery point measurement unit. And a recovery point of the base point determined to be highly reliable based on a comparison result between the predicted distance corresponding to each recovery point and the actual measurement distance. Is preferably detected as the position of the vehicle.

  Further, the driving support device of the present invention is a completely shielded place where GPS signals transmitted from the plurality of GPS satellites are completely shielded based on the position of the vehicle detected by the position detector described above, or The present invention is characterized in that a vehicle position at a place where the number of GPS satellites captured is less than a predetermined number is calculated, and driving assistance is executed using the calculated vehicle position.

  Further, the position detection method of the present invention receives GPS signals transmitted from a plurality of GPS satellites, and acquires the received power of each GPS signal and the satellite position of each GPS satellite from the received GPS signal. A position detection method that is executed in a position detection device that includes a machine, a storage unit that stores 3D map data including position information and shape information of a building, and a control unit, and is executed in the control unit On the basis of the satellite position of each GPS satellite acquired by the GPS receiver and the three-dimensional map data stored in the storage unit, the GPS signal transmitted from each GPS satellite is Calculated by a shielding section calculating step for calculating a shielding section shielded by a building existing around the route on the travel route of the vehicle and the shielding section calculating step. In the shielding section, a shielding point measuring step for measuring a point where the received power of each GPS signal acquired by the GPS receiver is a predetermined threshold value or less as a shielding point, and the shielding point measuring step The positional relationship between an arbitrary base point and the other shielding points among the plurality of shielding points measured is obtained as an estimated distance based on the GPS signal and an actually measured distance based on a detection value related to the distance of the vehicle. A vehicle position detecting step of detecting, as a position of the vehicle, a shielding point of the base point that is determined to be highly reliable based on a comparison result between the predicted distance corresponding to a shielding point and the actually measured distance. Features.

  The position detection device, the position detection method, and the driving support device according to the present invention have an effect of reducing the possibility of occurrence of a detected position error of the vehicle and detecting the position of the vehicle with high accuracy.

FIG. 1 is a block diagram showing an example of the configuration of a position detection system according to the present invention. FIG. 2 is a diagram illustrating an example of a building existing around the travel route of the vehicle. FIG. 3 is a diagram illustrating an example of a shielding section in which a GPS signal transmitted from a GPS satellite is shielded by a building. FIG. 4 is a diagram illustrating an example of a shielding point where the received power of the GPS signal is equal to or less than a predetermined threshold. FIG. 5 is a diagram illustrating an example of the distribution of shielding points created by moving each shielding point other than the base point to the base point side. FIG. 6 is a diagram illustrating an example of a distribution of shielding points including a plurality of shielding points determined to have high reliability and outliers determined to have low reliability. FIG. 7 is a diagram illustrating an example of a distribution of shielding points at which all shielding points are determined to have low reliability. FIG. 8 is a diagram illustrating an example of a recovery point where the received power of the GPS signal is greater than a predetermined threshold. FIG. 9 is a flowchart showing an example of position detection processing executed by the position detection system according to the present invention. FIG. 10 is a flowchart illustrating an example of the vehicle position detection process. FIG. 11 is a flowchart illustrating an example of the position detection process based on the recovery point. FIG. 12 is a flowchart illustrating an example of processing for determining whether or not position detection processing is necessary in accordance with the traveling environment.

  Hereinafter, embodiments of a position detection device, a position detection method, and a driving support device according to the present invention will be described in detail with reference to the drawings. In addition, this invention is not limited by this embodiment. In addition, constituent elements in the following embodiments include those that can be easily assumed by those skilled in the art or those that are substantially the same.

Embodiment
The configuration of the position detection system according to the present invention will be described with reference to FIGS. FIG. 1 is a block diagram showing an example of the configuration of a position detection system according to the present invention. FIG. 2 is a diagram illustrating an example of a building existing around the travel route of the vehicle. FIG. 3 is a diagram illustrating an example of a shielding section in which a GPS signal transmitted from a GPS satellite is shielded by a building. FIG. 4 is a diagram illustrating an example of a shielding point where the received power of the GPS signal is equal to or less than a predetermined threshold. FIG. 5 is a diagram illustrating an example of the distribution of shielding points created by moving each shielding point other than the base point to the base point side. FIG. 6 is a diagram illustrating an example of a distribution of shielding points including a plurality of shielding points determined to have high reliability and outliers determined to have low reliability. FIG. 7 is a diagram illustrating an example of a distribution of shielding points at which all shielding points are determined to have low reliability. FIG. 8 is a diagram illustrating an example of a recovery point where the received power of the GPS signal is greater than a predetermined threshold.

  In FIG. 1, reference numeral 10 denotes a vehicle, reference numeral 11 denotes an ECU (electronic control unit as a control unit), reference numeral 12 denotes a GPS receiver that receives a GPS signal, and reference numeral 13 is mounted on the vehicle 10. Is a vehicle information network (CAN: Control Area Network) composed of transmission paths connected to various sensors, 14 is a display that outputs image information, 15 is a speaker that outputs audio information, Reference numeral 16 denotes a storage unit that stores various data necessary for the processing of the ECU 11, and reference numerals 20-1 to 20-3 denote GPS (Global Positioning System) satellites that distribute GPS signals to the vehicle 10. Further, in FIG. 1, reference numeral 11a is a shielding section calculation unit, reference numeral 11b is a shielding point measurement unit, reference numeral 11c is a vehicle position detection unit, reference numeral 11d is a comparison unit, and reference numeral 11e is a reliability determination. 11 f is a vehicle position determination unit, 11 g is a processing stop unit, and 11 h is a recovery point measurement unit. In the present embodiment, the position detection device includes an ECU 11, a GPS receiver 12, and a storage unit 16.

  Here, in FIG. 1, an ECU 11 is an electronic control unit mounted on the vehicle 10, and the position of the vehicle 10 based on various data obtained from the GPS receiver 12, the vehicle information network 13, the storage unit 16, and the like. It has a function of generating output data including at least information and outputting the output data via the display 14 and the speaker 15. Here, the ECU 11 includes a shielding section calculation unit 11a, a shielding point measurement unit 11b, a vehicle position detection unit 11c, a processing stop unit 11g, and a recovery point measurement unit 11h. The vehicle position detection unit 11c further includes a comparison unit 11d, a reliability determination unit 11e, and a vehicle position determination unit 11f.

  In the ECU 11, the shielding section calculation unit 11 a obtains the satellite position of each GPS satellite 20-1 to 3 acquired by the GPS receiver 12, and the position information and shape information of the building stored in the storage unit 16. Based on the three-dimensional map data 16a included, the shielding section where the GPS signals transmitted from the GPS satellites 20-1 to 20-3 are shielded by the buildings existing around the traveling route of the vehicle 10 is displayed on the traveling route of the vehicle 10. It is the shielding area calculation means which calculates by. In the present embodiment, the travel route of the vehicle 10 means, for example, a route from the departure point to the destination of the vehicle 10 searched by route search means described later. The building existing around the traveling route means a building existing within a predetermined distance from the traveling route, and includes, for example, a building that can be a shielding object for shielding GPS signals such as a high-rise building and a tunnel. The shielding section calculation unit 11a determines whether or not a building exists on the line connecting the vehicle 10 and the GPS satellite 20, and is on a travel route where the building exists on the line connecting the vehicle 10 and the GPS satellite 20. The predetermined section is calculated as a shielding section.

  For example, as shown in FIG. 2, the shielding section calculation unit 11a confirms in advance the existence of a high-rise building or tunnel as a building that can be a shielding object existing around the travel route of the vehicle 10 from the three-dimensional map data 16a. Then, the shielding section calculation unit 11a extracts a region a surrounded by the confirmed high-rise building and a region b near the tunnel as shielding section candidates. Next, as illustrated in FIG. 3, when a tunnel is taken as an example of a building, the shielding interval calculation unit 11 a calculates the shielding interval of each GPS satellite 20-1 to 3 for the extracted region b near the tunnel. In FIG. 3, an example of calculating a shielding section for one GPS satellite 20 will be described in order to simplify the description. Based on the satellite position of the GPS satellite 20 acquired by the GPS receiver 12 and the position information and shape information of the tunnel existing in the region b on the travel route of the vehicle 10, the shielding section calculation unit 11 a A geometrical calculation is performed on the traveling route where the GPS signal transmitted from the vehicle is shielded by the tunnel.

  Returning to FIG. 1, the shielding point measuring unit 11b determines a point where the received power of each GPS signal acquired by the GPS receiver 12 is equal to or less than a predetermined threshold within the shielding interval calculated by the shielding interval calculation unit 11a. It is a shielding point measuring means for measuring as a shielding point. In the present embodiment, the predetermined threshold is a detection threshold that is an intermediate value between the normal received power and the shielded received power measured in advance, and is stored in the storage unit 16.

  For example, as shown in FIG. 4, the shielding point measurement unit 11b monitors the received power of the GPS signal transmitted from the target GPS satellite 20 acquired by the GPS receiver 12 of the vehicle 10 traveling along the travel route. Then, a power reduction timing that is equal to or lower than a predetermined threshold that is measured in advance as a detection threshold is detected. That is, whether the direct wave of the GPS signal transmitted from the target GPS satellite 20 is shielded by the shielding object by monitoring whether the reception power of the GPS signal is equal to or lower than the predetermined threshold value. Determine whether or not. Then, the shielding point measurement unit 11b determines that the power reduction timing at which the received power is equal to or less than the predetermined threshold is the timing when the vehicle 10 has entered the shielding section at this shielding section entry timing. Measure as a point. Specifically, the shielding point measurement unit 11b measures the position of the vehicle 10 based on the GPS signal, measured immediately before the time when the shielding section approach timing is detected, as the shielding point. The shielding point measurement unit 11b measures the shielding points corresponding to the GPS satellites 20-1 to 20-3 by executing this shielding point measurement process for the GPS satellites 20-1 to 20-3.

  Returning to FIG. 1, the vehicle position detection unit 11 c determines the positional relationship between an arbitrary base point and each other shielding point among the plurality of shielding points measured by the shielding point measurement unit 11 b and the predicted distance based on the GPS signal. The measured shielding distance based on the detection value related to the distance of the vehicle 10 is obtained, and the shielding point of the base point determined to be highly reliable based on the comparison result between the predicted distance corresponding to each shielding point and the measured distance is determined. Vehicle position detecting means for detecting the position. In the present embodiment, one shielding point is determined as a base point from a plurality of shielding points measured by the shielding point measuring unit 11b, and the base point and each of the base points are set close to the base point side except for the determined base point. Whether or not the difference from the shielding point is equal to or smaller than a predetermined error is compared, and the shielding point of the base point determined to be highly reliable based on the comparison result is detected as the position of the vehicle 10. Details of the processing of the vehicle position detection unit 11c will be described below in the order of processing of the comparison unit 11d, the reliability determination unit 11e, and the vehicle position determination unit 11f further provided in the vehicle position detection unit 11c.

  Here, the comparison unit 11d is a comparison unit that obtains a difference between the predicted distance corresponding to each shielding point and the actually measured distance. Specifically, in this embodiment, the comparison unit 11d determines one shielding point as a base point from a plurality of shielding points measured by the shielding point measurement unit 11b, and each shielding point other than the determined base point and the base point. Is measured as a predicted distance from a GPS signal, and is measured as a measured distance from a detected value related to the vehicle speed of the vehicle 10, and each measured distance corresponding to each measured predicted distance Addition or subtraction is performed so that each shielding point approaches the base point side.

  In the present embodiment, the comparison unit 11d determines one shielding point as a base point from the plurality of shielding points measured by the shielding point measurement unit 11b, and the distance between the determined base point and each shielding point other than the base point Is measured as a predicted distance from the GPS signal, and is measured as a measured distance from the vehicle speed pulse as a detected value related to the vehicle speed of the vehicle 10, and each measured distance corresponding to each measured predicted distance is determined as each measured distance other than the base point. By adding or subtracting so that the shielding point approaches the base point side, each shielding point other than the base point is moved to the base point side to create a distribution of a plurality of shielding points. It is assumed that a detection value (for example, a vehicle speed pulse) related to the vehicle speed of the vehicle 10 is acquired by a vehicle speed sensor (not shown) connected to the vehicle information network 13.

  More specifically, the case where three shielding points are measured by the shielding point measurement unit 11b will be described as an example. The comparison unit 11d uses the shielding point closest to the vehicle 10 among the three shielding points as a base point. By measuring the distance between the determined base point and the two shielding points other than the base point by the predicted distance and the actually measured distance, and subtracting the corresponding actually measured distance from each measured predicted distance, The other two shielding points are moved to the base point side to create a distribution of the three shielding points. In addition, when the comparison unit 11d uses the shielding point farthest from the vehicle 10 among the three shielding points as a base point, the comparison unit 11d calculates the distance between the determined base point and two shielding points other than the base point as a predicted distance and an actually measured distance. By measuring and adding each measured distance corresponding to each measured predicted distance, two shielding points other than the base point are moved to the base point side, and a distribution of three shielding points is created. In addition, the comparison unit 11d measures the distance between the determined base point and the shield point closest to the vehicle 10 with the predicted distance and the actually measured distance when the intermediate shield point among the three shield points is used as the base point. The measured distance is added to the measured predicted distance, and the distance between the determined base point and the shielding point farthest from the vehicle 10 is measured by the predicted distance and the measured distance, and the measured predicted distance is calculated. Then, by subtracting the actually measured distance, two shielding points other than the base point are moved to the base point side, and a distribution of the three shielding points is created.

  For example, as illustrated in FIG. 5, a case where three shielding points 1 to 3 respectively corresponding to the three GPS satellites 20-1 to 20-3 are measured by the shielding point measurement unit 11b will be described as an example. First, the comparison unit 11d determines that the GPS signal 1 transmitted from the GPS satellite 20-1 closest to the vehicle 10 among the three shielding points 1 to 3 measured on the travel route of the vehicle 10 is based on the tunnel building. The shielded shielding point 1 is determined as a base point. Then, the comparison unit 11d calculates the distance between the shielding points between the shielding point 1 determined as the base point and the shielding point 2 where the GPS signal 2 transmitted from the GPS satellite 20-2 is shielded by the tunnel building. The measured distance is measured based on the GPS signal, and the measured distance is measured based on the vehicle speed pulse. In addition, the comparison unit 11d calculates the distance between the shielding points between the shielding point 1 determined as the base point and the shielding point 3 where the GPS signal 3 transmitted from the GPS satellite 20-3 is shielded by the tunnel building. The measured distance is measured based on the GPS signal, and the measured distance is measured based on the vehicle speed pulse.

  Next, as shown in FIG. 5, the shielding point measurement unit 11 b performs the measurement distance based on the vehicle speed pulse corresponding to the distance between the shielding points between the shielding point 1 and the shielding point 2, and the shielding point 1 and the shielding point 3. By subtracting the measured distance based on the vehicle speed pulse corresponding to the distance between the shielding points between and the predicted distance based on the corresponding GPS signals, the two shielding points 2 and 3 are moved to the shielding point 1 side. It is moved and the distribution of the three shielding points 1-3 is created. In this way, by the processing of the comparison unit 11d, the shielding points 1 to 3 respectively corresponding to the respective GPS satellites 20-1 to 3 are virtually measured at the same point by aligning the shielding points 1 with the base point. In the next process, the difference between the shielding points 1 to 3 can be compared.

  Returning to FIG. 1, the reliability determination unit 11 e determines that a set of difference shielding points that are equal to or less than a predetermined error based on the detection value is highly reliable, and trusts a shielding point that is larger than the predetermined error as an outlier. This is a reliability determination unit that determines that the reliability is low. Specifically, the reliability determination unit 11e compares the difference between the base point and each shielding point based on a plurality of shielding points in a state where each shielding point other than the base point is brought closer to the base point side by the comparison unit 11d. A set of shielding points where the difference is less than or equal to a predetermined error is determined to be highly reliable, and a shielding point where the difference is greater than a predetermined error is determined as an outlier and the reliability is determined to be low. In the present embodiment, the reliability determination unit 11e compares the difference between the base point and each shielding point on the distribution of the plurality of shielding points created by the comparison unit 11d, and a plurality of shielding points whose difference is equal to or less than the pulse error. Is a reliability determination unit that determines that the reliability of the set is high, and determines that the reliability is low by using a shielding point whose difference is larger than the pulse error as an outlier. Here, when the example of the detection value related to the vehicle speed of the vehicle 10 is a vehicle speed pulse, the predetermined error based on the detection value is an error assumed when the vehicle speed pulse is acquired. For example, scale correction by GPS is performed. If completed, it is less than 1%.

  For example, as illustrated in FIG. 6, the reliability determination unit 11 e compares the difference between the base point and each shielding point, leaves only a set of a plurality of shielding points whose difference is equal to or less than the pulse error, and the difference is a pulse. Occlusion points larger than the error are excluded as outliers. Usually, there are about 10 visible satellites, so there are about 10 shielding points in the distribution. Therefore, in this embodiment, the reliability determination unit 11e determines that a set is formed when the difference between each shielding point and the base point corresponding to about half of the whole is equal to or less than the pulse error. And As described above, the process of the reliability determination unit 11e determines that the set has been detected as expected and determines that the reliability is high. On the other hand, outliers are excluded because they are judged to be low in reliability because the reflected wave is erroneously detected or there is shielding in an unintended place. Moreover, as shown in FIG. 7, when all the shielding points are larger than the pulse error, the reliability determination unit 11e determines that the position and shape of the shielding object are not as expected and are not shielded at the assumed location. To do. In this case, the reliability determination unit 11e determines that the reliability is low, and stops the vehicle position detection process performed in the next process. Thereby, possibility that the position error of the vehicle detected by the next processing will occur can be reduced.

  Returning to FIG. 1, the vehicle position determination unit 11f calculates an average value of each of the plurality of shielding points included in the set determined to be highly reliable by the reliability determination unit 11e, and corresponds to the calculated average value. Vehicle position determining means for determining a point as the position of the vehicle 10. Here, as illustrated in FIG. 6 described above, the vehicle position determination unit 11f, when there is a set determined to be highly reliable by the reliability determination unit 11e, a plurality of shielding points included in the set. The average value of is calculated. On the other hand, as illustrated in FIG. 7 described above, the vehicle position determination unit 11f does not perform these processes when there is no set. As a result, the position of the vehicle can be determined with high accuracy only from the set of shielding points that are unlikely to cause a position error of the detected vehicle, that is, the set of shielding points that are determined to be highly reliable.

  Here, it is considered that the higher the received power, the lower the possibility of receiving a direct wave rather than a reflected or diffracted wave. Therefore, in the present embodiment, the vehicle position determination unit 11f receives the GPS signal acquired by the GPS receiver 12 among the shielding points included in the set determined to be highly reliable by the reliability determination unit 11e. The average value may be calculated by applying a weighted average to the shielding points where the received power is larger than the received power at each shielding point. As a result, an average value closer to the shielding point where the received power is large can be determined as the vehicle position, and the accuracy and reliability of vehicle position detection can be improved.

  Further, it is considered that the detection error is smaller as the power change is steeper. Therefore, in the present embodiment, the vehicle position determination unit 11f receives the GPS signal acquired by the GPS receiver 12 among the shielding points included in the set determined to be highly reliable by the reliability determination unit 11e. The average value may be calculated by applying a weighted average to the shielding point where the power change of the power changes more rapidly than the power change of the received power at each shielding point. Thereby, the average value closer to the shielding point where the power change is steep can be determined as the vehicle position, and the accuracy and reliability of the vehicle position detection can be improved.

  In addition, the processing stop unit 11g includes the three-dimensional map data 16a further including travel environment information indicating a city area or a suburb stored in the storage unit 16, and the vehicle position based on the GPS signal received by the GPS receiver 12. Based on the above, it is determined whether the current driving environment is an urban area or a suburb, and when it is determined that the current driving environment is a suburb, the shielding section calculation unit 11a, the shielding point measurement unit 11b, and the vehicle position detection unit 11c This is a process stop means for stopping the process.

  Here, the accuracy of the position detection processing by the shielding section calculation unit 11a, the shielding point measurement unit 11b, and the vehicle position detection unit 11c in the present embodiment is the high accuracy of the three-dimensional map data 16a stored in the storage unit 16. It is thought that it rises with it. Normally, the maintenance of 3D map data is performed from an urban area such as the center of a city, and there are many shielding objects such as features in the urban area, and the GPS accuracy tends to deteriorate. On the other hand, in a place such as a suburb away from the city area, the tendency is opposite to that in the city area. Therefore, the accuracy of the position detection process is more effective in the urban area than in the suburbs. Therefore, in the present embodiment, the position detection process having a low effect is executed by performing control so as not to be performed in a situation where the accuracy of the position detection process in the suburbs or the like is considered to be low by the process of the process stop unit 11g. The situation can be reduced.

  Further, the recovery point measurement unit 11h measures a recovery point as a recovery point by measuring a point where the received power of each GPS signal acquired by the GPS receiver 12 is greater than the predetermined threshold value from a state below the predetermined threshold value. Means.

  For example, as shown in FIG. 8, the recovery point measurement unit 11h monitors the received power of the GPS signal transmitted from the target GPS satellite 20 acquired by the GPS receiver 12 of the vehicle 10 traveling along the travel route. Then, a power rise timing that is larger than a predetermined threshold value measured in advance as a detection threshold value is detected. In other words, the recovery point measurement unit 11h monitors whether or not the received power of the GPS signal is greater than a predetermined threshold value, thereby determining whether or not the direct wave of the GPS signal transmitted from the target GPS satellite 20 has been received. judge. Then, the shielding point measurement unit 11b determines that the power increase timing at which the received power is greater than the predetermined threshold is the timing at which the shielding section has exited, and recovers the point at which the vehicle 10 has exited the shielding section at this shielding section exit timing. Measure as a point. Specifically, the recovery point measurement unit 11h measures, as the recovery point, the position of the vehicle 10 based on the GPS signal, which is measured immediately after the shielding section exit timing is detected. The recovery point measurement unit 11h measures a plurality of recovery points respectively corresponding to the GPS satellites 20-1 to 20-3 by executing the recovery point measurement process for the GPS satellites 20-1 to 20-3. Thereby, the above-mentioned vehicle position detection unit 11c determines the positional relationship between an arbitrary base point and each other recovery point among the plurality of recovery points measured by the recovery point measurement unit 11h, and the predicted distance based on the GPS signal. The recovery point of the base point determined to be highly reliable based on the comparison result between the predicted distance corresponding to each recovery point and the actual measurement distance is obtained as an actual measurement distance based on the detection value related to the distance of the vehicle 10. It can be detected as a position. As a result, the position detection process can be executed not only based on the distribution of a plurality of shielding points, but also based on the distribution of a plurality of recovery points. In addition, the reliability can be further improved.

  In addition, the ECU 11 searches for a travel route of the vehicle 10 from the departure point to the destination using the three-dimensional map data 16a further including road network data based on a route search condition including at least the departure point and the destination. Route search means may be provided.

  In FIG. 1, a GPS receiver (GNSS receiver) 12 is a communication unit that receives GPS signals distributed from GPS satellites 20-1 to 20-3. In the present embodiment, the GPS receiver 12 receives GPS signals transmitted from the plurality of GPS satellites 20-1 to 20-3, and receives the received power of each GPS signal and the satellite of each GPS satellite from the received GPS signal. Get the position. Then, the GPS receiver 12 provides the ECU 11 with the received power of each acquired GPS signal and the satellite position of each GPS satellite.

  The vehicle information network 13 is an in-vehicle network composed of transmission paths connected to various sensors mounted on the vehicle 10. The vehicle information network 13 provides the ECU 11 with vehicle state information indicating the state of the vehicle 10 detected by various sensors. Here, the various sensors include, for example, an azimuth sensor, a vehicle speed sensor, an accelerator opening sensor, a brake sensor, a peripheral monitoring sensor, and a direction indication switch.

  The display 14 is a display unit that displays information provided by the ECU 11. For example, the display 14 may be a display that displays a device meter or navigation. The speaker 15 is sound output means for outputting information provided by the processing of the ECU 11 as sound. In the present embodiment, the display 14 and the speaker 15 may be configured as a driving assistance device together with the ECU 11. For example, the driving assistance device is a completely shielded place where GPS signals transmitted from the plurality of GPS satellites 20-1 to 20-3 are completely shielded based on the position of the vehicle 10 detected by the position detector as described above. The vehicle position at is calculated, and driving assistance is executed using the calculated vehicle position. The driving support may be, for example, support for providing information for calling attention regarding an obstacle (such as a preceding vehicle or an oncoming vehicle) with respect to the vehicle 10 based on the calculated own vehicle position, or based on the calculated own vehicle position. Support for navigating surrounding driving environments on a map may be used. Moreover, ECU11 may be connected with the vehicle control apparatus which is not shown in figure, and a vehicle control apparatus may be comprised with ECU11 as a driving assistance device. In this case, the driving assistance may be assistance for vehicle control for avoiding an obstacle based on the calculated own vehicle position.

  The storage unit 16 is for storing data, and is, for example, a RAM (Random Access Memory), a ROM (Read Only Memory), or a hard disk. In this embodiment, the memory | storage part 16 memorize | stores at least the three-dimensional map data 16a containing the positional information and shape information of a building. The position information of the building is information indicating the position of the building by latitude and longitude. The shape information of the building is information indicating the shape of the building by the height and the width. Here, the three-dimensional map data 16a may further include traveling environment information indicating an urban area or a suburb. The three-dimensional map data 16a may further include road network data including a plurality of nodes and links connecting the nodes. In the present embodiment, the three-dimensional map data 16 a stored in the storage unit 16 is periodically acquired and updated from an external device (such as a map database server) connected to be communicable with the vehicle 10.

  In FIG. 1, GPS satellites 20-1 to 20-3 are artificial satellites that deliver GPS signals to the vehicle 10 at predetermined time intervals or in response to a request from the vehicle 10. Although an example in which three GPS satellites exist has been described with reference to FIG. 1, the number of GPS satellites is not limited to this. There are actually about 10 visible satellites.

  Hereinafter, the position detection process executed by the position detection system having the above-described configuration will be described with reference to FIGS. FIG. 9 is a flowchart showing an example of position detection processing executed by the position detection system according to the present invention. FIG. 10 is a flowchart illustrating an example of the vehicle position detection process. FIG. 11 is a flowchart illustrating an example of the position detection process based on the recovery point. FIG. 12 is a flowchart illustrating an example of processing for determining whether or not position detection processing is necessary in accordance with the traveling environment. Each process shown in FIGS. 9 to 12 is repeatedly executed by the ECU 11 in parallel.

  As shown in FIG. 9, the shielding section calculation unit 11 a includes the satellite positions of the GPS satellites 20-1 to 3 acquired by the GPS receiver 12, and the building position information stored in the storage unit 16 and Based on the three-dimensional map data 16a including the shape information, the GPS signal transmitted from each of the GPS satellites 20-1 to 20-3 is shielded by a building existing around the travel route of the vehicle 10 (see FIG. 3). Is calculated on the travel route of the vehicle 10 (step ST-10).

  Then, the shielding point measurement unit 11b determines that the reception power of each GPS signal acquired by the GPS receiver 12 is equal to or less than a predetermined threshold within the shielding interval calculated by the processing of the shielding interval calculation unit 11a in step ST-10. The measured point is measured as a shielding point (see FIG. 4) (step ST-20).

  And the vehicle position detection part 11c is based on the GPS signal about the positional relationship of arbitrary base points and each other shielding point among several shielding points measured by the process of the shielding point measurement part 11b in step ST-20. The shielding point of the base point determined to be highly reliable based on the comparison result between the predicted distance and the measured distance corresponding to each shielding point, which is obtained as an actually measured distance based on the predicted distance and the detected value related to the distance of the vehicle 10 Is detected as the position of the vehicle 10 (step ST-30). Thereafter, the position detection process shown in FIG.

  Here, the detail of the vehicle position detection process performed by the vehicle position detection part 11c in step ST-30 is demonstrated with reference to FIG. As illustrated in FIG. 10, the comparison unit 11d generates a comparison result by obtaining a difference between the predicted distance and the actually measured distance corresponding to each shielding point (step ST-31). Specifically, in step ST-31, the comparison unit 11d determines, in the present embodiment, one shielding point as a base point from a plurality of shielding points measured by the processing of the shielding point measurement unit 11b, and the determined base point And the distance between each shielding point other than the base point is measured as a predicted distance from the GPS signal, and measured as a measured distance from the detected value related to the vehicle speed of the vehicle 10, and corresponds to each measured predicted distance. By adding or subtracting each measured distance so that each shielding point other than the base point approaches the base point side, a distribution of a plurality of shielding points (see FIG. 5) is generated as a comparison result.

  And the reliability determination part 11e has high reliability the set of the shielding points of the difference which becomes below the predetermined error based on a detection value based on the comparison result produced by the process of the comparison part 11d in step ST-31. Then, it is determined that the shielding point that is larger than the predetermined error is an outlier and the reliability is low (step ST-32). Specifically, in step ST-32, the reliability determination unit 11e compares the difference between the base point and each shielding point on the distribution of the plurality of shielding points created by the processing of the comparison unit 11d in step ST-31. Then, it is determined that the set of a plurality of shielding points whose difference is equal to or smaller than the pulse error (see FIG. 6) is highly reliable, and the shielding point whose difference is larger than the pulse error is regarded as an outlier (see FIG. 6). It is determined that the value is low (step ST-32).

  Then, the vehicle position determination unit 11f determines whether or not there is a set of a plurality of shielding points determined to be highly reliable by the process of the reliability determination unit 11e in Step ST-32 (Step ST-33). .

  In Step ST-33, when it is determined that there is a set of a plurality of shielding points determined to have high reliability (see FIG. 6) (Step ST-33: Yes), the vehicle position determination unit 11f determines whether there is a step ST In -33, an average value of each of the plurality of shielding points included in the set determined to be highly reliable by the process of the reliability determination unit 11e is calculated, and a point corresponding to the calculated average value is set as the vehicle position. Determine (step ST-34).

  In step ST-34, the vehicle position determination unit 11f includes the GPS receiver 12 among the plurality of shielding points included in the set determined to have high reliability by the processing of the reliability determination unit 11e in step ST-33. The average value may be calculated by weighting the received power of the GPS signal acquired by the above-described weighting average for the shield points where the received power is larger than the received power of each shield point. Further, in step ST-34, the vehicle position determination unit 11f receives the GPS reception among the plurality of shielding points included in the set determined to be highly reliable by the processing of the reliability determination unit 11e in step ST-33. The power change of the received power of the GPS signal acquired by the machine 12 is weighted and averaged by applying a weight to the shield point where the power change changes abruptly compared to the power change of the received power at each shield point. The average value may be calculated. Then, the vehicle position detection process shown in FIG.

  Returning to step ST-33, when it is determined that there is no set of a plurality of shielding points determined to have high reliability (see FIG. 7) (step ST-33: No), the vehicle position determination unit 11f The vehicle position detection process shown in FIG. 10 is terminated without determining the position.

  Next, the position detection process based on the recovery point will be described with reference to FIG. The process shown in FIG. 11 is performed after the process shown in FIGS. 9 and 10 is executed. As shown in FIG. 11, the recovery point measurement unit 11 h sets a point where the received power of each GPS signal acquired by the GPS receiver 12 is greater than the predetermined threshold value from a state below the predetermined threshold value as a recovery point. Measure (Step ST-25). And the vehicle position detection part 11c is based on the GPS signal about the positional relationship of arbitrary base points and each other recovery point among several recovery points measured by the process of the recovery point measurement part 11h in step ST-25. The recovery point of the base point that is obtained as an actual measurement distance based on the predicted distance and the detected value related to the distance of the vehicle 10 and is determined to be highly reliable based on a comparison result between the prediction distance corresponding to each recovery point and the actual measurement distance Is detected as the position of the vehicle 10 (step ST-30). Specifically, in step ST-30, the comparison unit 11d determines one recovery point as a base point from the plurality of recovery points measured by the process of the recovery point measurement unit 11h in step ST-25, and determines the determined base point In a state where each recovery point other than is close to the base point side, it is determined whether or not the difference between the base point and each recovery point is equal to or less than a predetermined error, and the reliability is determined based on the comparison result. The recovery point of the base point is detected as the position of the vehicle 10.

  More specifically, in step ST-30, the comparison unit 11d obtains a difference between the predicted distance and the actually measured distance corresponding to each recovery point. Then, the reliability determination unit 11e determines that the set of recovery points of differences that are equal to or smaller than the predetermined error based on the detection value is high in reliability, and uses a recovery point that is larger than the predetermined error as an outlier and has low reliability. Is determined. Then, the vehicle position determination unit 11f determines whether there is a set of a plurality of recovery points determined to have high reliability by the processing of the reliability determination unit 11e.

  Here, when it is determined that there is a set of a plurality of recovery points that are determined to be highly reliable, the vehicle position determination unit 11f is included in the set that is determined to be highly reliable by the processing of the reliability determination unit 11e. An average value of each of the plurality of recovery points included is calculated, and a point corresponding to the calculated average value is determined as the position of the vehicle. Here, the vehicle position determination unit 11f receives the GPS signal acquired by the GPS receiver 12 among the plurality of recovery points included in the set determined to be highly reliable by the processing of the reliability determination unit 11e. The average value may be calculated by applying a weighted average by applying a weight to a recovery point where the received power is larger than the received power at each recovery point. In addition, the vehicle position determination unit 11f receives the received power of the GPS signal acquired by the GPS receiver 12 among the plurality of recovery points included in the set determined to be highly reliable by the processing of the reliability determination unit 11e. The average value may be calculated by applying a weighted average to the recovery points where the power change of the recovery power changes more rapidly than the power change of the received power at each recovery point. Thereafter, the vehicle position detection process ends. On the other hand, when it is determined that there is no set of a plurality of recovery points determined to have high reliability, the vehicle position determination unit 11f ends the vehicle position detection process without determining the position of the vehicle.

  Next, with reference to FIG. 12, a process for determining whether or not the position detection process is necessary according to the traveling environment will be described. The process illustrated in FIG. 11 may be performed before the position detection process illustrated in FIGS. 9 to 11 described above is performed, or may be performed while the position detection process is being performed. As illustrated in FIG. 12, the processing stop unit 11 g includes the three-dimensional map data 16 a further including traveling environment information indicating a city area or a suburb stored in the storage unit 16, and the GPS signal received by the GPS receiver 12. The current traveling environment is determined based on the vehicle position based on (ST40). And the process stop part 11g determines whether the present driving | running | working environment is a city area or a suburb based on the result determined in step ST-40 (step ST-50). Here, when it is determined in step ST-50 that the current traveling environment is an urban area (step ST-50: urban area), the process stop unit 11g executes the position detection process without stopping the position detection process. (Step ST-60). That is, in this case, the position detection process by the shielding section calculation unit 11a, the shielding point measurement unit 11b, and the vehicle position detection unit 11c as illustrated in FIG. On the other hand, when it is determined in step ST-50 that the current driving environment is a suburb (step ST-50: suburb), the position detection process is performed by the shielding section calculation unit 11a, the shielding point measurement unit 11b, and the vehicle position detection unit 11c. Is stopped (step ST-70). Then, the process shown in FIG.

  As described above, according to the present embodiment, it is possible to reduce the possibility of occurrence of a detected vehicle position error and to detect the position of the vehicle with high accuracy as compared with the related art. For example, in the prior art, the area where radio waves emitted by a base station are defined and the points where radio waves are interrupted are determined. However, the location where radio waves are interrupted fluctuates due to radio wave shielding and reflection. There was an error in the position. This is because there are many features such as buildings and moving objects such as other vehicles in the area where the vehicle travels, and radio wave shielding and reflection occur irregularly in such places. This is because the point of interruption changes. On the other hand, according to the present embodiment, the reliability of the position detection of the radio wave area end can be improved by the radio wave reliability determination, and the vehicle position can be detected with high accuracy. As a result, it is possible to accurately detect the position immediately before being completely shielded, such as when entering a tunnel, so the accuracy of the autonomous navigation base point in a completely shielded place such as a tunnel can be improved, and the position accuracy can be ensured. The range can be expanded.

10 Vehicle 11 ECU
11a Shielding interval calculation unit
11b Shielding point measurement unit
11c Vehicle position detector
11d comparator
11e Reliability judgment unit
11f Vehicle position determination unit
11g Processing stop
11h Recovery point measurement unit 12 GPS receiver 13 Vehicle information network 14 Display 15 Speaker 16 Storage unit
16a 3D map data 20-1 to 3 GPS satellites

Claims (8)

A GPS receiver that receives GPS signals transmitted from a plurality of GPS satellites, and acquires the received power of each GPS signal and the satellite position of each GPS satellite from the received GPS signal;
A storage unit for storing three-dimensional map data including position information and shape information of the building;
Based on the satellite position of each GPS satellite acquired by the GPS receiver and the three-dimensional map data stored in the storage unit, a GPS signal transmitted from each GPS satellite is generated around the vehicle travel route. A shielding section calculating unit that calculates a shielding section shielded by an existing building on the travel route of the vehicle;
A shielding point measuring unit for measuring, as a shielding point, a point where the received power of each GPS signal acquired by the GPS receiver is equal to or less than a predetermined threshold within the shielding interval calculated by the shielding interval calculation unit; ,
The positional relationship between an arbitrary base point and other shielding points among the plurality of shielding points measured by the shielding point measuring unit is based on the predicted distance based on the GPS signal and the detection value related to the distance of the vehicle. A vehicle position detection unit that detects the measured shielding distance and detects the shielding point of the base point determined to be highly reliable based on the comparison result between the predicted distance and the measured distance corresponding to each shielding point, as the position of the vehicle When,
A position detection device comprising: The vehicle position detector
A comparison unit for obtaining a difference between the predicted distance corresponding to each shielding point and the measured distance;
A reliability determination unit that determines that a set of shielding points having a difference equal to or smaller than a predetermined error based on the detection value is highly reliable, and determines that a shielding point that is larger than the predetermined error is an outlier and has low reliability. When,
A vehicle position for calculating an average value of each shielding point included in the set determined to be high by the reliability determination unit and determining a position corresponding to the calculated average value as the position of the vehicle A decision unit;
The position detecting device according to claim 1, further comprising: The vehicle position determining unit
Among the shielding points included in the set determined to be highly reliable by the reliability determination unit, the reception power of the GPS signal acquired by the GPS receiver is the reception power of the shielding points. The position detection device according to claim 2, wherein the average value is calculated by applying a weighted average by applying a weight to a shielding point where the received power is higher in comparison. The vehicle position determining unit
Among the shielding points included in the set determined to be highly reliable by the reliability determination unit, the power change of the received power of the GPS signal acquired by the GPS receiver is The position detection device according to claim 2, wherein the average value is calculated by applying a weighted average to a shielding point where the power change changes more rapidly than the power change of the received power. . The three-dimensional map data further includes traveling environment information indicating an urban area or a suburb,
Based on the 3D map data stored in the storage unit and the vehicle position based on the GPS signal received by the GPS receiver, it is determined whether the current driving environment is the city area or the suburb. And when it is determined that the current driving environment is the suburb, a process stop unit that stops the processing of the shielding section calculation unit, the shielding point measurement unit, and the vehicle position detection unit,
The position detecting device according to any one of claims 1 to 4, further comprising: A recovery point measurement unit that measures, as a recovery point, a point where the received power of each GPS signal acquired by the GPS receiver is greater than the predetermined threshold value from a state below the predetermined threshold value,
Further comprising
The vehicle position detector
The positional relationship between an arbitrary base point and other recovery points among a plurality of recovery points measured by the recovery point measurement unit is based on a predicted distance based on the GPS signal and a detection value related to the distance of the vehicle. It is obtained as an actual distance, and the recovery point of the base point determined to be highly reliable based on a comparison result between the predicted distance corresponding to each recovery point and the actual distance is detected as the position of the vehicle. The position detection device according to any one of claims 1 to 5.   A completely shielded place where GPS signals transmitted from the plurality of GPS satellites are completely shielded based on the position of the vehicle detected by the position detecting device according to any one of claims 1 to 6. Alternatively, a driving support device that calculates a vehicle position at a location where the number of GPS satellites captured is less than a predetermined number, and executes driving support using the calculated vehicle position. A GPS receiver that receives GPS signals transmitted from a plurality of GPS satellites, acquires the received power of each GPS signal and the satellite position of each GPS satellite from the received GPS signal, and the position information and shape of the building A position detection method executed in a position detection device including a storage unit that stores 3D map data including information, and a control unit,
Executed in the control unit,
Based on the satellite position of each GPS satellite acquired by the GPS receiver and the three-dimensional map data stored in the storage unit, a GPS signal transmitted from each GPS satellite is generated around the vehicle travel route. A shielding section calculating step of calculating a shielding section shielded by an existing building on the travel route of the vehicle;
A shielding point measuring step for measuring, as a shielding point, a point where the received power of each GPS signal acquired by the GPS receiver is equal to or less than a predetermined threshold within the shielding section calculated in the shielding section calculation step. When,
The positional relationship between an arbitrary base point and other shielding points among the plurality of shielding points measured in the shielding point measurement step is based on a predicted distance based on the GPS signal and a detection value related to the distance of the vehicle. Vehicle position detection for detecting the shielding point of the base point determined as highly reliable based on the comparison result between the predicted distance and the measured distance corresponding to each shielding point as the position of the vehicle Steps,
A position detection method comprising:

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