JP2015004543A - Vehicle position recognition device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a vehicle position recognition device configured to determine whether a vehicle is traveling on an express highway or an open road simply, and to properly perform map matching of a current position of the vehicle.SOLUTION: A vehicle position recognition device includes: a GPS sensor for receiving a GPS signal; a vehicle position specifying unit which specifies a position of a vehicle on the basis of the GPS signal received by the GPS sensor; a map data storage unit which stores map data; an intersection position approach determination unit which determines that a first road having no intersection and a second road having an intersection exist in parallel and the first road approaches the intersection position of the second road, in a traveling direction of the vehicle, on the basis of the map data stored in the map data storage unit; a rader device which measures a distance to an object located at both sides of the vehicle; and an intersection determination unit which determines whether there is an intersection or not, on the basis of a measurement result obtained by the rader device, when the intersection position approach determination unit determines approach to the intersection position.

Description

  The present invention relates to a vehicle position recognition device.

  Conventionally, as a device for recognizing the position of the host vehicle, there has been a navigation device that mounts a map and identifies a current position on a map mounted by GPS (Global Positioning System). The navigation device performs map matching that appropriately matches the current position on the map based on the position data measured by the GPS, based on the shape of the road on the map.

  However, for example, when traveling on a section where a highway and a general road are parallel, it may not be possible to determine which one is traveling based only on the position data obtained by GPS, and map matching may occur incorrectly. there were.

  As a conventional technique, for example, in order to determine whether the current position is on an elevated road or a road under the elevated road, the presence of an elevated road above the vehicle is detected by a radar mounted on the vehicle, and the road under the elevated road is detected. There was a technique to determine that you are traveling.

Also, it is determined whether the vehicle is traveling on a general road or on a highway based on whether or not a specific image such as a traffic light or an ETC gate is included in an image around the vehicle photographed by a camera. There was technology to do.
(For example, see Patent Document 1 and Patent Document 2).
JP 2004-205418 A JP 2006-317286 A

  However, in the above prior art, when the general road is not in a vertical relationship with the expressway, it cannot be determined that the vehicle is traveling on the general road.

  In addition, in order to recognize images such as traffic lights and ETC gates, a large amount of reference image data must be stored and a high-speed image processing apparatus is required, and installation of the apparatus is expensive.

  Therefore, an object of the present invention is to provide a vehicle position recognition device that easily determines whether a running road is an expressway or a general road and correctly maps the current position of the host vehicle.

  A vehicle position recognition device according to the present invention includes a GPS sensor that receives a GPS signal, a host vehicle position specifying unit that specifies the position of the host vehicle based on the GPS signal received by the GPS sensor, and a map that stores map data Based on the map data stored in the data storage unit and the map data storage unit, the first road without an intersection and the second road with an intersection run in parallel in the traveling direction of the host vehicle, An intersection position approach determination unit that determines that the first road approaches the intersection position of the second road, a radar device that measures the distance to the measurement object on the side of the host vehicle, and the intersection position approach And an intersection determination unit that determines the presence or absence of an intersection based on a measurement result measured by the radar device when the determination unit determines approach to the intersection position.

  According to the embodiment of the present invention, it is possible to provide a vehicle position recognition device that can easily determine whether a running road is an expressway or a general road and correctly map-match the current position of the host vehicle.

Overall configuration diagram of vehicle position recognition device (A) Detection zone, (b) Parallel vehicle detection result, and (c) Guardrail detection result, explaining the determination method in the measurement object determination unit Flowchart explaining operation of vehicle position recognition device The figure explaining the outline of the intersection to be judged Graph showing the measurement distance to the object according to the distance in the direction of travel

  Hereinafter, an embodiment which is an example of the present invention will be described with reference to the drawings.

  FIG. 1 is a diagram showing an example of the overall configuration of the vehicle position recognition device 1.

  In FIG. 1, a vehicle position recognition device 1 includes a GPS sensor 11, a vehicle sensor 12, a host vehicle position specifying unit 13, a map matching unit 14, a map data storage unit 15, a left radar 16 a, a right radar 16 b, and a measured object determination unit 17. , The intersection determination unit 18 and the road determination unit 19. The vehicle position recognition device 1 is, for example, a navigation device that notifies a driver of a route to a destination using a display device (not shown).

  The GPS sensor 11 receives a radio wave from a GPS satellite (not shown) and inputs a GPS signal composed of coordinate information of the own vehicle to the own vehicle position specifying unit 13. Note that radio waves from GPS satellites cannot be received, for example, inside a tunnel. Further, in a mountainous area where the sky is not clearly visible or in valleys of buildings in the city center, it is difficult for radio waves from GPS satellites to reach, so the error in the coordinate position of the GPS signal may increase.

  The vehicle sensor 12 detects the vehicle speed, the vehicle longitudinal acceleration (front-rear G), and the vehicle lateral acceleration (lateral G), and inputs them to the vehicle position specifying unit 13.

  The own vehicle position specifying unit 13 appropriately corrects the coordinate position of the own vehicle based on the vehicle speed, the front and rear G, and the lateral G information input from the vehicle sensor 12 with respect to the input GPS signal. For example, when the host vehicle is traveling in a tunnel, the position of the host vehicle is detected by detecting acceleration / deceleration and steering of the host vehicle based on the information on the vehicle speed and the longitudinal G, and the coordinate position obtained from the GPS signal is corrected. The own vehicle position specifying unit 13 inputs the specified coordinate position of the own vehicle to the map matching unit 14.

  The map data storage unit 15 stores map data including road data. In the road data, the position of the road is described together with the coordinate information. In the present embodiment, the road data includes, as “first road”, data of an expressway and an elevated road without an intersection, for example, and data of an ordinary road with an intersection as “second road”, for example. included.

  In an actual road, there is a section in which the first road and the second road are built close to each other. For example, there is a section where the first road is built over the second road. In addition, there is a section in which a second road is built next to the first road. In the present embodiment, a section in which the first road and the second road are close to each other at a certain distance is referred to as a “parallel section”. In the road data stored in the map data storage unit 15, the display color of the first road and the display color of the second road are color-coded to make the display easy to see. In the road data, the shape of an interchange or a ramp connecting the first road and the second road is stored. In the parallel section, the positional relationship between the first road and the second road can be expressed by painting. The map data storage unit 15 may store the width of the road intersecting the second road in the parallel section at the intersection and the shape of the intersection.

  The map matching unit 14 matches the position of the host vehicle on the road data based on the coordinate position input from the host vehicle position specifying unit 13 and the road data stored in the map data storage unit 15. Since the GPS signal includes a measurement error as described above, the map matching unit 14 compares the traveling locus with the road shape at an intersection, for example, and corrects the current position of the host vehicle as appropriate. The map matching unit 14 can detect the transfer between the first road and the second road based on the interchange of the road data stored in the map data storage unit 15 and the shape of the ramp. However, for example, in a branch that hardly changes the traveling direction, it may be difficult to detect the transfer of the road only by the road shape, and the parallel section in which the first road and the second road are close to each other. During traveling, map matching may be performed while the road being traveled is erroneous using only GPS information. In the present embodiment, the above problem is solved by the intersection determination described below.

  The map matching unit 14 includes an intersection position approach determination unit 141. The intersection position approach determination unit 141 determines a parallel section from the position of the host vehicle on the road data, and determines approach to the second road and the intersection position in the parallel section of the first road. The intersection position approach determination unit 141 outputs information on the position of the host vehicle and intersection data to the intersection determination unit 18 when approach is determined. The intersection data gives the intersection determination unit 18 position information for performing intersection determination. The intersection data may be, for example, the distance from the current position of the host vehicle to the intersection. Moreover, the data of the width and shape of the intersection of the 2nd road memorize | stored in the map data storage part may be sufficient. Details of the intersection determination using the intersection data will be described later.

  The left radar 16a is attached to the left rear of the vehicle, and is a radar device that detects an object such as a guard rail, another vehicle, or an obstacle on the left side of the vehicle. As a radar system, for example, an FMCW (Frequency-Modulated Continuous Waves) system radar using a frequency modulation system or a pulse radar system using a pulse modulation system can be used. For the purpose of detecting an object such as another vehicle in a vehicle-mounted radar system, it is possible to use, for example, UWB (Ultra Wide Band) having a high detection capability at a distance of about 10 m from the own vehicle. . This facilitates detection even for an object having a small projected area and a small reflected wave intensity when viewed from the front of the radar irradiation direction. The left radar 16a is used in common with an obstacle detection function radar that detects, for example, a blind spot of a rearview mirror or side mirror using an array antenna in which a plurality of receiving antenna elements are arranged in an array in the horizontal direction. Can do. A detection signal from the left radar 16 a is input to the measurement object determination unit 17. In the present embodiment, the intersection detection radar can be shared with the obstacle detection radar, so that the presence or absence of the intersection can be detected without installing a new sensor.

  The right radar 16b is a radar device that is attached to the right rear of the vehicle and detects an object on the right side of the vehicle. Since the details of the radar are the same as those of the left radar 16a, description thereof is omitted.

  In the present embodiment, either the left radar 16a or the right radar 16b can be attached to detect the shape of the intersection on the left side or the right side of the vehicle. Further, the shape of the intersection on both sides can be detected by using both the left radar 16a and the right radar 16b. In addition, priority is given to the detection of the intersection by the left radar 16a, and when the intersection cannot be detected by the left radar 16a, the intersection can be detected by the right radar 16b.

  The measurement object determination unit 17 analyzes the detection signals input from the left radar 16a and the right radar 16b, and determines the detected object. The determination target is, for example, a guardrail, another vehicle that is parked, another vehicle that is running in parallel, and the like. When the measured object determining unit 17 determines that the object is a guardrail, the measured object determining unit 17 outputs the distance from the host vehicle to the object to the intersection determining unit 18.

  The intersection determination unit 18 specifies the position of the intersection to be measured based on the own vehicle position and the intersection data input from the map matching unit 14, and uses the distance information to the target object input from the measurement object determination unit 17. The presence or absence of is determined.

  The road determination unit 19 determines whether the traveling road is the first road or the second road based on the information about the presence / absence of the intersection input from the intersection determination unit 18. The road determination information determined by the road determination unit 19 is output to the map matching unit 14 and used for correction of map matching.

  Each functional unit described in FIG. 1 can be implemented by a hardware circuit that realizes each function. The vehicle position recognition apparatus 1 is a computer system including a CPU and a memory, and can be implemented by mounting each functional unit by software and executing the software stored in the memory by the CPU. . Also, within the scope of executing the functions described in the present embodiment, a plurality of function units may be mounted together as one function unit, or one function unit may be further divided into a plurality of function units and mounted. Can do.

  FIG. 2 illustrates an example of a determination method in the measurement object determination unit 17, (a) a detection zone, (b) a parallel vehicle detection result, and (c) a guardrail detection result. Note that the determination method in the measurement object determination unit 17 is the same for the right radar 16b, and thus the description thereof is omitted.

  In FIG. 2A, the measurement object determination unit 17 detects the presence or absence of the measurement object by dividing the detection result for the radar emitted from the left radar 16a into detection zones divided into grid areas on the horizontal plane. For example, in the case of a monopulse radar, the radar irradiation is performed by irradiating a monopulse at a predetermined interval (cycle) and performing modulation / demodulation processing by UWB modulation to obtain radar reflection intensity for each lattice area. The presence or absence of the measurement object can be detected with a predetermined intensity as a threshold. The measurement object determination unit 17 stores the detection result of the object for a certain period for each illustrated lattice area in an internal storage unit (not illustrated).

  In FIG. 2B, when there is a parallel vehicle on the left rear, the detection result shown in the lower diagram of FIG. 2B is obtained in the lattice area described in FIG. A black portion of the illustrated lattice area is a detection portion detected as a parallel vehicle. When the detected object is a parallel vehicle, the radar emitted from the left radar 16a is observed according to the right shape of the parallel vehicle. When the parallel vehicle is traveling at the same speed as that of the host vehicle, the detection result for each grid area shown in the lower diagram of FIG. 2B remains constant over time. If the host vehicle is traveling faster than the parallel running vehicle, the black portion of the lattice area remains unchanged, and the characteristic that the black portion moves from the right to the left in the drawing is detected. On the other hand, when the host vehicle is running slower than the parallel running vehicle, the black portion of the lattice area remains unchanged, and the characteristic that the black portion moves from the left to the right in the drawing is detected. The measured object determination unit 17 can determine whether the detected object is a stationary object or a moving object based on the speed of the host vehicle obtained from the vehicle sensor 12 and the detection result from the left radar 16a. Moreover, the measurement object determination unit 17 can estimate that the detection object is a vehicle based on the shape or size of the detection object indicated by the lattice area.

  FIG. 2C illustrates a detection result when a guard rail, a side wall, or the like is present on the left side of the host vehicle. In FIG.2 (c), as for the grid | lattice-like area, the detection part has become a straight line as illustration. The measurement object determination unit 17 can detect that the object is a stationary object based on the vehicle speed of the host vehicle and the transition of the detection result. Further, it can be detected from the linear shape of the detected grid area that the object has a planar shape. The measurement object determination unit 17 can infer from the detection results that the object is a guardrail or the like. Since the guardrail and the side wall have a large radar reflection area and a stable shape, a reflected wave having a strong intensity is stably detected. The measurement object determination unit 17 may estimate the object based on the intensity and stability of the reflected wave.

  The intersection determination unit 18 sets an intersection determination section based on the vehicle position from the map matching unit 14 and the intersection data, and determines whether there is an intersection based on the distance information input from the measurement object determination unit 17. To do. A method for determining the presence or absence of an intersection will be described with reference to FIG. FIG. 3 is a flowchart for explaining an example of the operation of the vehicle position recognition device 1.

  In FIG. 3, the map matching unit 14 is traveling in the parallel section described above based on the vehicle position information input from the vehicle position specifying unit 13 and the road information stored in the map data storage unit 15. Whether or not (S11) and loop until entering the parallel section (N in S11). In the parallel section, because the host vehicle is traveling in the section where the first road and the second road are running side by side, it is not possible to determine which road is traveling only by the own vehicle position information. It is. The parallel section is a section in which the first road and the second road are in parallel, but in step S11, in the section in which the first road and the second road are in parallel, It may be a section after passing through a position where there is an interconnection between the first road and the second road such as a ramp. This is because when there is no interconnection, it can be estimated that the host vehicle continues to travel on the road that has been traveled until now. Moreover, when there is no intersection position in the parallel section based on the information of the intersection position described later stored in the map data storage unit 15, the parallel section need not be determined. Thereby, an unnecessary determination operation can be prevented.

  When the own vehicle enters the parallel section (Y in S11), the map matching unit 14 determines approach to the intersection position (S12). The intersection position is the position of the intersection of the second road stored in the map data storage unit 15. The intersection position may be, for example, the center position of the intersection, or an end of the intersection (a portion where the guardrail disappears, the left end of the intersection road, etc.). The approach to the intersection position is input from the map matching unit 14 to the intersection determination unit 18 as distance information to the intersection position. Here, the distance to the intersection may be a fixed value such as 100 m or 50 m, for example. Moreover, an individual value may be used for each intersection. Further, the approach to the intersection position may be based on the intersection data. Further, it may vary depending on the speed of the host vehicle.

  When approaching the intersection position (Y in S12), the intersection determination unit 18 confirms the presence / absence of a left-side parallel vehicle (S13). For example, when the second road has two lanes and the host vehicle is traveling in the right lane, another vehicle may be traveling in the left lane. In the present embodiment, since the shape of the intersection is measured by the left radar 16a, the parallel running vehicle on the left side of the own vehicle becomes an obstacle to the measurement and may affect the measurement result.

  When there is no left side parallel vehicle (N in S13), the intersection determination unit 18 measures the left intersection (S14), and determines the presence or absence of the intersection (S15). The details of the intersection determination method will be described with reference to FIGS. FIG. 4 is a diagram illustrating an example of an outline of an intersection to be determined.

  In FIG. 4, the illustrated intersection is a planar ten-shaped road intersection with the center point O as the center of the intersection. The host vehicle enters the intersection in the traveling direction from point A to point B in the figure. There are guard rails parallel to the traveling direction on the left side of the host vehicle, and a1 to a4 are end points of the guard rails. The map matching unit 14 in FIG. 1 determines that the vehicle is approaching the intersection position when the distance from the center point o of the intersection reaches a predetermined distance, and outputs distance information to the intersection determination unit 18 (FIG. 3). S12). The distance information exemplified in the present embodiment is a distance in the vehicle traveling direction after determining approaching an intersection. When the distance information is input, the intersection determination unit 18 confirms that there is no parallel vehicle on the left side of the host vehicle based on the measured distance from the left radar 16a to the target (S13 in FIG. 3). Record the measured distance to the object. FIG. 5 is a graph showing an example of the measurement distance to the object according to the distance in the traveling direction.

  In FIG. 5, the X axis indicates the distance in the vehicle traveling direction, and the Y axis indicates the measurement distance. The distance 0, which is the origin of the X axis of the graph, is the position where the map matching unit 14 determines the approach of the intersection position. When the distance from the center point O reaches the point A of d1, the intersection determination unit 18 starts determining the intersection from the measurement distance. The measurement distance l1 is a distance to the guardrail. The guardrail is determined from the fact that the measurement distance is constant in the traveling direction. In the present embodiment, the first threshold is provided at l2 where the measurement distance is larger than l1 by a predetermined distance. Further, a second threshold is provided for the distance in the traveling direction of the measurement distance of 12 or more, and the intersection determination unit 18 is an intersection when a section whose measurement distance is equal to or greater than the first threshold is equal to or greater than the second threshold. Is determined. The first threshold value and the second threshold value are fixed values, but may be variable based on intersection data, for example.

  The first peak in the graph of FIG. 5 is obtained by measuring the distance from the break of the guardrails a1 to a2 in FIG. 4 to the building. The measurement distance to the building is not less than the first threshold value l2. On the other hand, the distance (a2-a1) in the traveling direction of the guardrail break is assumed to be less than the second threshold in the present embodiment. Therefore, the intersection determination unit 18 does not determine the section from a1 to a2 as an intersection.

  Next, in the peak of the graph appearing from a3 to a4, the distance in the traveling direction where the measurement distance is equal to or greater than the first threshold (a4-a3) is equal to or greater than the second threshold. Therefore, the intersection determination unit 18 determines the section from a3 to a4 as an intersection.

  In the present embodiment, the X-axis is the distance in the traveling direction. However, for example, the X-axis may be used as time, and the second threshold may be determined as the intersection passing time.

  Further, in this embodiment, information on the intersection position is stored in the map data storage unit 15 in advance, and the approach to the intersection position is set as the condition for starting the intersection determination. For example, the lateral measurement is always performed by the left radar 16a. The distance may be obtained to determine the presence or absence of an intersection.

  The determination of the intersection is performed up to a point B that is a distance d2 away from the center point O. Depending on the intersection, it may intersect with a wide road with a median, and if there is a sufficient distance in the direction of travel to determine the intersection, point B is a negative value, that is, before the center of the intersection It can also be provided.

  Returning to FIG. 3 again, the intersection determination unit 18 notifies the road determination unit 19 of the presence or absence of an intersection, and the road determination unit 19 determines whether the traveling road is the first road or the second road. To generate road discrimination information of the first road / second road (S16). For example, even when an intersection is detected, the road determination can be changed according to the vehicle speed, an image from a television camera (not shown), an instruction from the driver, or the like. Even when no intersection is detected, road discrimination can be designated or changed by an instruction from the driver. The road determination unit 19 notifies the map matching unit 14 of road determination information. The intersection measuring unit 18 measures the left intersection (S14) and determines whether or not there is an intersection (S15).

  On the other hand, when there is a parallel vehicle on the left side (Y in S13), the measurement object determination unit 17 checks whether there is a parallel vehicle on the right side by the right radar 16b (S18). This is because if there is a parallel vehicle on the left side, the intersection will be shaded by radar due to the parallel vehicle, and the shape of the intersection on the left side in the traveling direction cannot be measured. Further, even when there is a parallel vehicle on the left side, the probability that an intersection can be determined is increased by performing measurement using the right radar 16b.

  When there is no parallel running vehicle on the right side, the intersection determination unit 18 measures the shape of the intersection on the right in the traveling direction with the right radar 16b in the same manner as the measurement with the left radar 16a described above (S19), and whether there is an intersection. (S15). The road shape on the right side in the traveling direction may have a median strip or an elevated bridge pier, for example, and the determination method may be different from the determination of the intersection shape on the left side in the traveling direction.

  When there is a parallel running vehicle on the right side (Y in S18), the operation according to the flowchart is terminated without determining the intersection.

  In the present embodiment, priority is given to intersection determination by the left radar 16a in the flowchart described in FIG. 3, but intersection determination may be performed with priority given to the right radar 16b.

  Alternatively, the intersection determination may be performed only by the left radar 16a or the right radar 16b. In that case, when there is a parallel running vehicle on the side for determining left and right, the flowchart is ended without determining the intersection.

  Further, the intersection may be determined using the left radar 16a and the right radar 16b simultaneously.

  The map matching unit 14 corrects the map matching of the road on which the host vehicle is traveling based on the road determination information notified from the road determination unit 19 (S17). The map matching correction can be notified to the driver by a screen display or sound of a display device (not shown). Further, when the vehicle position recognition device 1 is a navigation device, the map matching unit 14 may perform a reroute to search again for the route being guided.

  As mentioned above, although the form for implementing this invention was explained in full detail, this invention is not limited to such specific embodiment, In the range of the summary of this invention described in the claim, Various modifications and changes are possible.

  For example, the number of radars that measure intersections can be further increased to improve accuracy.

  Further, even when approaching the intersection position, if the intersection determination is performed once, the intersection determination may not be performed if a predetermined time or a predetermined distance has not elapsed.

DESCRIPTION OF SYMBOLS 1 Vehicle position recognition apparatus 11 GPS sensor 12 Vehicle sensor 13 Own vehicle position specific | specification part 14 Map matching part 141 Intersection position approach determination part 15 Map data memory | storage part 16a Left radar 16b Right radar 17 Measured object determination part 18 Intersection determination part 19 Road determination Part

Claims (7)

A GPS sensor for receiving GPS signals;
An own vehicle position specifying unit for specifying the position of the own vehicle based on the GPS signal received by the GPS sensor;
A map data storage unit for storing map data;
Based on the map data stored in the map data storage unit, a first road without an intersection and a second road with an intersection run in parallel in the traveling direction of the host vehicle, and the second road An intersection position approach determination unit that determines that the vehicle approaches an intersection position of
A radar device that measures the distance to the measurement object on the side of the vehicle;
A vehicle position recognition device comprising: an intersection determination unit that determines the presence or absence of an intersection based on a distance to a measurement object measured by the radar device when the intersection position approach determination unit determines an approach to the intersection position. .   2. The vehicle position recognition device according to claim 1, wherein the intersection determination unit determines that there is an intersection when a section having a distance to the measurement object equal to or greater than a predetermined value is equal to or greater than a predetermined distance in the traveling direction of the host vehicle. .   The intersection determination unit does not determine the presence or absence of an intersection when the radar apparatus detects a parallel vehicle when the intersection position approach determination unit determines approach to the intersection position. The vehicle position recognition apparatus according to 2. The radar device is disposed on both the left and right sides of the host vehicle,
4. The intersection determination unit according to claim 1, wherein even when a parallel vehicle is detected by one of the left and right radar devices, the presence or absence of an intersection is determined by measurement using the other radar device. 5. Vehicle position recognition device.   The road determination part which produces | generates the road determination information whether the road where the own vehicle is drive | working is the said 1st road or the said 2nd road according to the presence or absence of the intersection determined by the said intersection determination part is further provided. The vehicle position recognition device according to claim 4. A map matching unit for matching the position of the identified vehicle with the map data;
The vehicle position recognition device according to claim 5, wherein the map matching unit corrects a road on which the host vehicle is traveling based on the road determination information generated by the road determination unit.   The vehicle position recognition device according to claim 6, wherein the map matching unit includes the intersection position approach determination unit.

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