JP2018036075A - Own vehicle position specification device and own vehicle position specification method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an own vehicle position specification device and an own vehicle position specification method with which it is possible to suppress a reduction in the accuracy of the own vehicle position.SOLUTION: An ECU 20 comprises a detection unit 21 for detecting a roadside object ahead of the own vehicle on the basis of the result of measurement by a measurement sensor 32 and a position recording unit 22 for recording the relative positions of a plurality of roadside objects when the plurality of roadside objects are detected by the detection unit 21. It also includes an estimated position calculation unit 24 which, when it is determined by a determination unit 23 that no registered roadside object is included, calculates an estimated position of a registered roadside object on the basis of the relative position of the same roadside object as the roadside object detected at the present point of time and the relative position of the registered roadside object out of the registered relative positions, and a position specification unit 26 for specifying the own vehicle position on a map on the basis of the result of aligning the calculated estimated position with the position on the map of the registered roadside object.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a vehicle position specifying device and a vehicle position specifying method for specifying a vehicle position on a map.

  2. Description of the Related Art Conventionally, an own vehicle position specifying device that specifies an own vehicle position on a map using roadside objects existing on the shoulders of roads such as curbs and guardrails is known. For example, the own vehicle position specifying device measures the position of a roadside object ahead of the own vehicle with a measuring device provided in the own vehicle, and based on the result of aligning the measured position with the position of the same roadside object on the map Correct the vehicle position on the map.

  Moreover, in patent document 1, the own vehicle which selects the feature used for specification of the own vehicle position from the some feature recognized in the captured image based on the recognition rate defined for each feature type A location device is disclosed. In Patent Document 1, a recognition rate is determined for a feature based on the ratio of each type that is successfully recognized by the image recognition process.

JP 2013-50412 A

  As described in Patent Document 1, when the recognition rate is set according to the type of roadside object, even the roadside object with a high recognition rate may be erroneously recognized. For example, when the surroundings of the host vehicle are dark or there are objects that obstruct the recognition of roadside objects such as plants around the roadside object, the roadside objects May be misrecognized. By misrecognizing the roadside object, the position of the roadside object different from this roadside object is aligned with the position of the roadside object registered on the map, which may reduce the accuracy of the vehicle position on the map. .

  The present invention has been made in view of the above problems, and an object of the present invention is to provide a vehicle position specifying device and a vehicle position specifying method that can suppress a decrease in the vehicle position accuracy.

  In order to solve the above-described problems, the present invention provides a vehicle position specifying device for specifying a vehicle position on a map based on roadside objects that exist along a road on which the vehicle travels. Based on the measurement result of the mounted measurement unit, a detection unit that detects the roadside object in front of the host vehicle, and when a plurality of the roadside objects are detected by the detection unit, the relative position of each roadside object is recorded. A position recording unit, a determination unit that determines whether or not the roadside object detected by the detection unit includes a registered roadside object registered in the map, and the registered roadside object is determined by the determination unit. If it is determined that it is not included, among the relative positions recorded by the position recording unit, the relative position of the same roadside object as the roadside object currently detected and the registered roadside object The registration based on relative position Based on a result of aligning the calculated estimated position and the position of the registered roadside object on the map based on an estimated position calculating unit that calculates an estimated position of the side object, the vehicle position on the map And a position specifying unit for specifying.

  If the detected roadside object does not include a registered roadside object used for specifying the vehicle position, the vehicle position cannot be specified based on the position of the registered roadside object. In this regard, in the above configuration, when a plurality of roadside objects are detected by the detection unit, the relative positions of the plurality of roadside objects are recorded. Then, when it is determined that the detected roadside object does not include the registered roadside object, the relative position of the roadside object that is recorded in the past and that is the same as the roadside object currently detected is An estimated position of the registered roadside object is calculated based on the relative position of the registered roadside object. Then, the vehicle position on the map is specified based on the result of aligning the calculated estimated position and the position of the registered roadside object on the map. In this case, if it is determined that the registered roadside object has not been detected, the vehicle's position on the map is identified based on the estimated position estimated from the relative position of the roadside object recorded in the past. It is possible to prevent the position from being aligned with the position of the registered roadside object on the map, and to suppress a decrease in the vehicle position accuracy.

The schematic block diagram of a vehicle control apparatus. The figure explaining the structure of a map. The figure explaining the method of specifying the own vehicle position on a map. The figure explaining calculation of a relative position. The figure explaining calculation of an estimated position. The flowchart explaining identification of the own vehicle position CP. The figure explaining the method of detecting the roadside thing ahead of the own vehicle. The figure explaining shape information. The figure explaining the specification of the own vehicle position in case the relative position is recorded. 7 is a flowchart for explaining in detail the processing in step S22 of FIG. The figure explaining calculation of an estimated position. The figure explaining the detection of the roadside thing ahead of the own vehicle based on 2nd Embodiment.

  Embodiments of a vehicle position specifying device and a vehicle position specifying method according to the present invention will be described with reference to the drawings. In the following embodiments, parts that are the same or equivalent to each other are denoted by the same reference numerals in the drawings, and the description of the same reference numerals is used. In this embodiment, the roadside object means a feature existing on the roadside of the road, and means a three-dimensional object that can specify the shape of the road such as a curb, a guardrail, or a road wall.

(First embodiment)
The own vehicle position specifying device according to the present embodiment is configured as a part of a vehicle control device that controls a vehicle. Further, the vehicle control device controls traveling of the host vehicle using the host vehicle position calculated by the host vehicle position specifying device. First, the configuration of the vehicle control device 100 will be described with reference to FIG. The vehicle control device 100 includes various sensors 30, an ECU 20 that functions as a vehicle position specifying device, and a driving support device 40.

  The various sensors 30 include a GPS receiver 31, a measurement sensor 32, a vehicle speed sensor 33, and a yaw rate sensor 34.

  The GPS receiver 31 functions as part of a well-known satellite positioning system (GNSS), thereby receiving radio waves transmitted from the satellite as GPS information. The GPS information includes the satellite position and the time when the radio wave is transmitted. The GPS receiver 31 calculates the distance from the satellite to the host vehicle CS based on the difference between the reception time when the GPS information is received and the transmission time included in the GPS information. Then, the calculated distance and the position of the satellite are output to the ECU 20.

  The measurement sensor 32 functions as a measurement unit, and measures a relative position with respect to the own vehicle in a roadside object in front of the own vehicle. When the measurement sensor 32 is a laser radar device, scan line data including the relative position of the measurement point (reflection point) of the roadside object ahead is generated by rotating the polygon mirror and scanning the pulsed laser beam. . Each measurement point included in the scan line data is acquired as a relative position on three-dimensional coordinates (X, Y, Z) with reference to the measurement sensor 32 mounted on the host vehicle.

  The vehicle speed sensor 33 is provided on a rotating shaft that transmits power to the wheels of the host vehicle, and detects the speed of the host vehicle based on the number of rotations of the rotating shaft. The yaw rate sensor 34 detects the yaw rate actually generated in the host vehicle, that is, the angular velocity around the center of gravity of the vehicle.

  ECU20 is comprised as a computer provided with CPU, ROM, and RAM. And CPU can function as each part shown in FIG. 1 by running the program memorize | stored in memory. Further, the ECU 20 is connected to the external memory 45, and by referring to a map recorded in the external memory 45, the position and shape of the road on which the host vehicle is traveling can be acquired.

  In the map, a link indicating a lane on the road and a node indicating a connection point of the lane are recorded. In this node, absolute coordinates on the map are recorded, and each position on the map can be detected by referring to the position of the node. Information such as the coordinates of the center of the lane for each predetermined distance, the number of own lanes, and the like are recorded in association with each link. In FIG. 2A, the center FM for each predetermined distance in one side lane is shown as the center of the lane. Further, the map may be provided with auxiliary points indicating positions on the road at predetermined distances in addition to nodes indicating lane connections.

  In addition, information on roadside objects arranged in the direction along the road is registered in the map. For example, in association with nodes and links, shape information and attribute information indicating the shape of roadside objects are registered in association with each other. Hereinafter, a roadside object whose position and shape information are registered on the map is referred to as a registered roadside object. In FIG. 2A, the curbs F1 and F2 correspond to registered roadside objects. Further, as illustrated in FIG. 2B, the shape information is formed by well-known vector data including coordinates of representative points of registered roadside objects and approximate curves connecting the representative points. Therefore, the position of the registered roadside object on the map can be referred to by this shape information.

  The ECU 20 determines the vehicle on the current map based on the result of aligning the relative position of the surrounding registered roadside object detected according to the measurement result of the measurement sensor 32 and the position of the registered roadside object on the map. Identify the location. In FIG. 3A, the ECU 20 uses the measurement sensor 32 to change the measurement point MP indicating the relative position of the registered roadside object Obr with respect to the host vehicle to the position RP of the registered roadside object indicated by the shape information on the map. It is aligned. For example, when each measurement point MP is represented by a vector based on the vehicle position, by adding a vector indicating the estimated vehicle position CP1 of the vehicle estimated on the map to this vector, Convert to a coordinate position. Then, by aligning the measurement point MP converted to the position on the absolute coordinate with the position RP of the registered roadside object, the amount of deviation between the two positions is calculated. For example, the relationship between the position and the position RP on the map is aligned using a determinant having the shift amount as an element, and the shift amount can be calculated by solving each element of the determinant. . Then, by correcting the estimated own vehicle position CP1 based on the calculated deviation amount, the own vehicle position on the map is specified by the corrected own vehicle position CP2.

  The driving support device 40 controls the traveling of the host vehicle based on the host vehicle position specified by the ECU 20. For example, the driving support device 40 predicts the future position of the host vehicle based on the host vehicle position, the vehicle speed, and the yaw rate, and uses the predicted future position and the road recognition result, so that the host vehicle is defined by a lane marking. Determine whether there is a risk of departure from your lane. For example, if the driving support device 40 has an alarm function, if it is determined that the host vehicle may deviate from the host lane, a warning is displayed on a display included in the host vehicle, or a speaker included in the host vehicle is used. A warning sound is generated. Further, if the driving support device 40 has a driving assist function, when it is determined that the host vehicle CS may deviate from the own lane, a steering force is applied to the steering device.

  Here, as shown in FIG. 3B, when the ECU 20 cannot detect the registered roadside object Obr, the vehicle position on the map cannot be specified. Further, when a roadside object Obn that is not registered in the map is erroneously detected as a registered roadside object Obr, the wrong position is matched with the position RP of the registered roadside object on the map, and the deviation amount is not an appropriate value. An error is caused in the own vehicle position CP2. Therefore, ECU20 is provided with each function shown in FIG. 1 in order to suppress the fall of the own vehicle position accuracy on a map.

  Returning to FIG. 1, the detection unit 21 detects a roadside object ahead of the host vehicle based on a measurement result by the measurement sensor 32 mounted on the host vehicle. FIG. 4A shows the position of the measurement point MP of the roadside object in front of the vehicle detected by the measurement sensor 32 at a predetermined height. The detection unit 21 extracts measurement points included in the scan line data and groups the measurement point groups to generate a segment that is a bundle of measurement points for each roadside object. A segment is generated by grouping measurement point groups according to the distance between measurement points and their positions. For example, in FIG. 4B, three segments SGa to SGc are generated by grouping the measurement point group in front of the vehicle. Therefore, the detection part 21 can detect the roadside object which exists ahead of a vehicle with the produced | generated segment.

  The position recording unit 22 records the relative position of each roadside object when the detection unit 21 detects a plurality of roadside objects. Further, as shown in FIG. 5A, the position recording unit 22 records the relative position on the history, and the history includes shape information indicating the shape of each roadside object from which the relative position is acquired. It is recorded in association. The shape information is calculated based on the segment generated by the detection unit 21, for example. Therefore, by referring to the shape information, it is possible to identify which roadside object each position corresponds to.

  The determination unit 23 determines whether the roadside object detected by the detection unit 21 includes a registered roadside object registered in the map. For example, the detection unit 21 compares the shape information of the roadside object detected this time with the shape information of the registered roadside object, and whether the roadside object detected this time is included in the roadside object detected this time based on the comparison result. Determine whether or not.

  The estimated position calculation unit 24 uses the relative position recorded by the position recording unit 22 when the determination unit 23 determines that the registered roadside object is not included in the roadside objects detected by the detection unit 21. Then, the estimated position of the registered roadside object is calculated based on the relative position of the same roadside object as the currently detected roadside object and the relative position of the registered roadside object. As shown in FIG. 5B, the estimated position ESP is calculated as a position shifted from the position of the currently detected roadside measurement point MP by the distance between the roadside objects recorded by the position recording unit 22. Is done.

  The own vehicle position estimation unit 25 estimates the position of the own vehicle on the map as the estimated own vehicle position. The own vehicle position estimating unit 25 estimates the own vehicle position by matching the position of the own vehicle with the position on the road in the map based on the positioning result of the own vehicle based on the GPS information and the value obtained by integrating the output of the vehicle speed sensor 33. Is calculated.

  The position specifying unit 26 specifies the vehicle position on the map based on the position of the roadside object in front of the vehicle. At this time, when the detection unit 21 detects a registered roadside object in front of the host vehicle, the vehicle position is specified based on the result of aligning the relative position of the registered roadside object and the position on the map. On the other hand, when the detection unit 21 has not detected the registered roadside object, the vehicle position is determined based on the result of aligning the estimated position calculated by the estimated position calculation unit 24 and the position of the registered roadside object on the map. Is identified.

  Next, the identification of the vehicle position performed by the ECU 20 will be described with reference to FIG. The flowchart shown in FIG. 6 is executed by the ECU 20 at a predetermined cycle. In the processing of FIG. 6, the case where the registered roadside object is a curb will be described as an example.

  In step S11, the vehicle position on the map is estimated. In step S12, information within a predetermined range from the estimated host vehicle position estimated in step S11 is acquired from the map. By acquiring the information in step S12, the ECU 20 can acquire the position and shape of the registered roadside object existing around the host vehicle from the map.

  In step S13, a roadside object ahead of the host vehicle is detected based on the measurement result by the measurement sensor 32. Step S13 functions as a detection process. In this embodiment, the ECU 20 groups a plurality of measurement points, which are measurement results obtained by the measurement sensor 32, based on positions in the road width direction with reference to the own lane, and sets each measurement point based on the grouped measurement points. Detect roadside objects. Fig.7 (a) has shown the position of the measurement point ahead of the own vehicle. FIG. 7B shows the position of each measurement point on the AA cross section in FIG.

  Specifically, the ECU 20 groups the relative positions of the measurement points extracted from the scan line data based on the position in the road width direction with respect to the own lane, thereby corresponding to each roadside object in front of the own vehicle. Generate a segment to 7A and 7B, each measurement point P is divided into two groups G1 and G2 based on the position in the road width direction (X-axis direction in the figure) from the center OM of the own lane. Therefore, the measurement point group which belongs to each group respond | corresponds to the segments SG1 and SG2 of a roadside thing, respectively. For example, in FIG. 7B, the curbstone closest to the road width direction from the center of the own lane is detected by the measurement point belonging to the segment SG1. Moreover, the road wall is detected by the measurement points belonging to the segment SG2.

  Returning to FIG. 6, in step S14, shape information indicating the shape of each roadside object detected in step S13 is created based on the distribution of measurement points. In the first embodiment, the ECU 20 calculates a gradient angle on each surface of the roadside object based on a segment that is a bundle of measurement points for each roadside object, and calculates the appearance frequency of the calculated gradient angle as shape information. To do. Here, the gradient angle means the angle of each surface when a line segment parallel to the height direction is used as a reference. Step S14 functions as a shape information creation unit.

  For example, as shown in FIG. 8 (a), if the roadside object is curb Ob1, the appearance frequency of the slope angle as shown in FIG. The appearance frequency FA with the surface gradient angle increases. On the other hand, if the roadside object is the road wall Ob2 as shown in FIG. 8C, the frequency of the gradient angle of the wall surface where the measurement points are scattered increases as shown in FIG. 8D. Therefore, the shape of the roadside object can be recognized using the distribution of the appearance frequency FA of the gradient angle θ.

  As an example of a method for calculating the appearance frequency of the gradient angle, the ECU 20 creates the gradient angle θ at a position where the roadside object is located based on the distribution of the measurement points in the segment. Then, the gradient angle θ at the position of the segment after the change is calculated by changing the position of the segment for calculating the gradient angle θ in the traveling direction (Y-axis direction). Then, by calculating the calculated gradient angles θ, the appearance frequency of the gradient angles is calculated. Step S14 functions as a shape recognition unit.

  In step S15, it is determined whether or not the host vehicle has entered a curved road. A curved road is more likely to have a different relative position of roadside objects than a straight road. Therefore, the ECU 20 prevents the relative position recorded on the straight road from being used during traveling on the curved road. Therefore, when it is determined that the host vehicle has entered a curved road (step S15: YES), in step S16, the relative position of each roadside object currently recorded in the history is deleted. Step S15 functions as a curved road determination unit.

  For example, the ECU 20 determines whether or not the host vehicle has entered a curved road based on a detection result by the yaw rate sensor 34 that detects a change in the direction of the host vehicle. In addition to this, a change in the shape of the road ahead of the host vehicle on the map may be detected, and based on the detection result, it may be determined whether the host vehicle has entered a curved road.

  In step S17, it is determined whether a plurality of roadside objects are detected. When a plurality of segments are generated by the process of step S13 (step S17: YES), in step S18, the relative position of each roadside object detected this time and the shape information created in step S14 are associated with each other and recorded in the history. . Step S18 functions as a position recording process. On the other hand, when only one roadside object has been detected (step S17: NO), the process proceeds to step S19 without recording the history.

  In step S19, it is determined whether the relative position (measurement point) of the same roadside object currently detected is recorded in the past. For example, the ECU 20 detects the roadside detected this time based on the comparison result obtained by comparing the shape information calculated from the segment of the roadside object detected this time in step S14 with the past shape information recorded in the history. It is determined whether or not the relative position of the same roadside object as the object has been recorded in the past.

  When the past relative position corresponding to the roadside object detected this time is not recorded in the history (step S19: NO), in step S24, the roadside object closest to the center of the own lane among the roadside objects detected this time The vehicle position on the map is specified based on the result of aligning the vehicle with the position on the map of the roadside closest to the center of the lane on the map. Step S24 functions as an unrecorded specifying unit.

  In FIG. 9A, the ECU 20 selects a relative position on the segment SG1 that is closest to the center OM of the own lane in the road width direction as a position alignment target. Next, as shown in FIG. 9B, the position of the curb F11, which is the roadside object closest to the center FM of the own lane on the map, is selected. Then, the vehicle position on the map is specified based on the result of aligning the relative position of the selected measurement point with the position of the roadside object (curbstone F11) selected on the map. Of course, when there is only one registered roadside object on the map, this registered roadside object is the roadside object at the closest position from the center FM of the own lane. Then, when the process of step S24 ends, the process shown in FIG. 6 is temporarily ended.

  On the other hand, when the past relative position corresponding to the roadside object detected this time is recorded in the history (step S19: YES), in step S20, the registered roadside object is included in the roadside objects detected by the process of step S13. It is determined whether or not. The ECU 20 determines whether or not a registered roadside object is included in the detected roadside object based on the comparison result of the shape information calculated this time by the process of step S14 and the shape information recorded in the history. judge. For example, the degree of similarity between the shape information calculated this time and the shape information recorded in the history is calculated, and when there is shape information with a high degree of similarity, it is determined that a registered roadside object is included. Step S19 functions as a determination step.

  If it is determined that the registered roadside object is included in the detected roadside object (step S20: YES), in step S21, the vehicle position is specified using the relative position of the registered roadside object detected this time. . In this case, the estimated host vehicle position CP1 estimated in step S11 is corrected based on the result of aligning the relative position of the measurement point in the segment corresponding to the registered roadside object with the position of the registered roadside object on the map.

  On the other hand, when it is determined that the registered roadside object is not included (step S20: NO), in step S22, the relative position recorded in the history and the same roadside object as the roadside object detected at the present time is displayed. An estimated position of the registered roadside object is calculated based on the relative position and the relative position of the registered roadside object. Step S22 functions as an estimated position calculation step.

  FIG. 10 is a flowchart for explaining in detail the process of step S22 of FIG. First, in step S31, the relative position of the same roadside object as the roadside object detected this time is extracted from the history. For example, the ECU 20 extracts the relative position of the same roadside object as the currently detected roadside object from the history by comparing the similarity between the shape information calculated this time and the shape information recorded in association with the history. .

  Next, in step S32, the relative position of the registered roadside object recorded at the same time as the relative position extracted in step S31 is extracted on the history. In Fig.11 (a), segment SG2 which shows the relative position of the roadside thing which is recorded on the history in the past rather than this process, and is registered on the map, and the registration roadside extracted at the same timing as this roadside thing A segment SG1 indicating the relative position of the object is extracted.

  In step S33, the distance between each roadside object is calculated from the relative positions extracted in steps S31 and S32. In the example of FIG. 11A, the distance D in the road width direction between the segment SG2 of the roadside object not registered in the map recorded in the history and the segment SG1 of the registered roadside object is calculated. For example, the ECU 20 may calculate the distance between a plurality of relative positions in the segment, and use the average of the calculated plurality of distances as the distance D between the roadside objects.

  In step S34, the estimated position of the registered roadside object corresponding to the roadside object detected this time is calculated by adding the distance calculated in step S33 to the relative position of the roadside object detected this time. In FIG. 11B, the estimated position ESP of the registered roadside object is calculated by adding the distance calculated in step S33 to the relative position of the roadside object detected this time. A plurality of estimated positions ESP of the registered roadside objects are calculated by adding the distance D calculated in step S33 to the plurality of relative positions in the segment SG2.

  Returning to FIG. 6, in step S23, the vehicle position on the map is specified based on the result of aligning the estimated position calculated in step S22 with the position of the registered roadside object on the map. For example, as shown in FIG. 3A, the ECU 20 calculates the deviation amount by aligning the estimated position ESP with the same curb position on the drawing. Then, by correcting the estimated vehicle position on the map based on the deviation amount, the position on the map is specified based on the corrected vehicle position. Step S23 functions as a position specifying step.

  Then, when the process of step S24 ends, the process shown in FIG. 6 is temporarily ended.

  As described above, in the first embodiment, the ECU 20 records the relative positions of the plurality of roadside objects when detecting the plurality of roadside objects. Then, when it is determined that the detected roadside object does not include the registered roadside object, the relative position and registration of the same roadside object currently detected among the relative positions recorded in the history are registered. Based on the relative position of the roadside object, the estimated position of the registered roadside object is calculated. Then, the vehicle position on the map is specified based on the result of aligning the calculated estimated position and the position of the registered roadside object on the map. In this case, when a registered roadside object is not detected, a decrease in the vehicle position accuracy is suppressed by specifying the vehicle position on the map based on the estimated position estimated from the relative position of the roadside object recorded in the past. be able to.

  The ECU 20 groups a plurality of measurement points, which are measurement results by the measurement sensor 32, based on positions in the road width direction with reference to the own lane, and detects each roadside object based on the grouped measurement points. . When a plurality of roadside objects exist at different positions, the roadside objects can be individually recognized by grouping the measurement points at which the roadside objects are measured by the positions in the road width direction. In this regard, in the above configuration, a plurality of measurement points are grouped based on the position in the road width direction with reference to the own lane, and each roadside object is detected based on the grouped measurement points. In this case, a plurality of roadside objects can be properly detected according to their positions, and the detection accuracy of each roadside object can be increased.

  When the relative position of the roadside object is not recorded in the history, the ECU 20 displays the relative position of the roadside object closest to the roadside direction from the center of the own lane among the roadside objects detected this time on the map. The vehicle position on the map is specified based on the result of alignment with the position of the roadside object closest to the road width direction from the center. When detecting a roadside object on the road, it is assumed that the relative position is not recorded. In this regard, in the above configuration, the relative position of the detected roadside object that is closest in the width direction from the center of the own lane is located at the position of the roadside object that is closest to the center of the own lane on the map. Based on the combined results, the vehicle position on the map was determined. In this case, even when the relative position is not recorded, it is possible to prevent the vehicle position from being identified on the map.

  The ECU 20 creates shape information indicating the shape of the roadside object based on the distribution of a plurality of measurement points, which are measurement results obtained by the measurement sensor 32, and records the shape information in association with the position of each roadside object. And it is determined whether the registered roadside object is detected based on the comparison result which compared the shape information produced by distribution of the measurement point measured this time with the shape information currently recorded on the map. Even when there are a plurality of roadside objects, the shape of each roadside object is likely to be different. By using this shape, each roadside object can be identified. In this respect, in the above configuration, whether or not the registered roadside object is detected based on the comparison result obtained by comparing the shape information created by the distribution of the measurement points measured this time with the shape information recorded on the map. Was decided. In this case, it is possible to accurately determine whether the roadside object detected by using the shape information is a registered roadside object.

  The ECU 20 determines whether or not the host vehicle has entered a curved road, and erases the currently recorded relative position when it is determined that the host vehicle has entered a curved road. In a curved road, the relative position between roadside objects is also likely to change greatly, and there is a high possibility that the relative position will be different from the straight road. In this regard, in the above configuration, when it is determined that the host vehicle has entered the curved road, the relative position currently recorded is deleted. In this case, it is possible to prevent the estimated position from being calculated based on the relative position between the roadside objects on the straight road while traveling on the curved road, and to prevent the accuracy of the estimated position from being lowered.

(Second Embodiment)
In this 2nd Embodiment, when detecting a roadside thing, a roadside thing is detected by grouping each measurement point by the position in the height direction on the basis of the own lane.

  FIG. 12 is a diagram for explaining detection of a roadside object in the second embodiment. In step S13 of FIG. 6, the ECU 20 groups the measurement points extracted in front of the host vehicle based on the position in the height direction with reference to the host lane. Therefore, it is divided into two groups G11 and G12 according to the position in the height direction from the own lane. Therefore, the measurement point groups belonging to each group respectively correspond to the roadside object segments SG11 and SG12. Then, each roadside object is detected by the generated segment.

  As described above, in the second embodiment, the ECU 20 groups the measurement points based on the position in the height direction with reference to the own lane, and detects each roadside object based on the grouped measurement points. In this case, each roadside object can be properly detected in roadside objects having different measurement point positions in the height direction.

(Other embodiments)
Instead of recording the position of the measurement point as a relative position in the history, the distance between a plurality of roadside objects may be recorded in the history. In this case, in step S18 of FIG. 6, the ECU 20 calculates the distance between the roadside objects from the measurement position of each roadside object, and records the calculated distance in the history.

  The ECU 20 may record the relative position between the roadside objects on the map instead of recording it in the history. In this case, the relative positions of the surrounding roadside objects not registered on the map are recorded in association with the positions of the registered roadside objects on the map.

  The relative position recorded in the history may be deleted when the traveling time after recording the previous relative position is equal to or longer than a predetermined distance. In this case, the ECU 20 records the accumulated travel time from the time when the relative position was recorded last time for each roadside object. Then, in step S15 in FIG. 6, the accumulated traveling time is compared with a threshold value, and when the accumulated traveling time exceeds the threshold value, the relative position of the corresponding roadside object recorded in the history is deleted. In addition, as an example of the threshold value for comparing the accumulated travel time, the value can be 10 minutes or more and 60 minutes or less, but is not limited to this, and is appropriately changed according to the shape of the road and the type of the registered roadside object. It may be a thing.

  The shape information calculated in step S14 in FIG. 6 is not limited to the appearance frequency of the gradient angle. For example, the ECU 20 may calculate an approximate curve indicating the shape of the roadside object based on the position of the measurement point, and use the calculated approximate curve as the shape information.

  The measurement sensor 32 may use a stereo camera device. When the measurement sensor 32 is a stereo camera device, a distance image provided with a three-dimensional distance is generated from a stereo image obtained by imaging the front of the host vehicle, and the stereo camera at the feature point of the roadside object included in the distance image is used as a reference. The relative position is sequentially calculated.

  DESCRIPTION OF SYMBOLS 20 ... ECU, 21 ... Detection part, 22 ... Position recording part, 23 ... Determination part, 24 ... Estimated position calculation part, 26 ... Position specification part, 32 ... Measurement sensor, CP ... Own vehicle position.

Claims (6)

A vehicle position specifying device (20) for specifying a vehicle position on a map based on roadside objects existing along a road on which the vehicle travels,
Based on the measurement result by the measurement unit (32) mounted on the host vehicle, the detection unit detects the roadside object ahead of the host vehicle;
A position recording unit that records a relative position of each roadside object when a plurality of the roadside objects are detected by the detection unit;
A determination unit that determines whether the roadside object detected by the detection unit includes a registered roadside object registered in the map;
When the determination unit determines that the registered roadside object is not included, among the relative positions recorded by the position recording unit, the same roadside object as the roadside object currently detected An estimated position calculating unit that calculates an estimated position of the registered roadside object based on the relative position and the relative position of the registered roadside object;
A vehicle position specification comprising: a position specifying unit for specifying the vehicle position on the map based on a result of aligning the calculated estimated position and the position of the registered roadside object on the map apparatus.   The detection unit groups a plurality of measurement points, which are measurement results by the measurement unit, based on a position in a road width direction or a position in a height direction with reference to the own lane, and each of the measurement points grouped The vehicle position specifying device according to claim 1, wherein each roadside object is detected based on the vehicle.   When the relative position is not recorded by the position recording unit, the position of the roadside object closest in the road width direction from the center of the own lane among the roadside objects detected this time is displayed on the map. An unrecorded specifying unit that specifies the position of the vehicle on the map based on a result of alignment with the position of the roadside object that is closest in the road width direction from the center of the vehicle. Vehicle positioning device. An information creation unit that creates shape information indicating the shape of the roadside object based on a distribution of a plurality of measurement points that are measurement results by the measurement unit;
The position recording unit records the shape information in association with the recorded relative position of each roadside object when a plurality of the roadside objects are detected by the detection unit,
The determination unit is based on a comparison result obtained by comparing the shape information created by the distribution of the measurement points measured this time by the information creation unit with the shape information recorded in the map. The own vehicle position specifying device according to any one of claims 1 to 3, wherein it is determined whether or not an object is detected. A curve road determination unit for determining whether or not the host vehicle has entered a curve road;
The said position recording part is the own vehicle position specifying device of Claim 1 which erase | eliminates the said relative position currently recorded when it determines with the said own vehicle approaching the said curve road. A vehicle position identification method for identifying a vehicle position on a map based on roadside objects existing along a road on which the vehicle travels,
A detection step of detecting the roadside object in front of the vehicle based on a measurement result by the measurement unit (32) mounted on the vehicle;
A position recording step of recording relative positions of the plurality of roadside objects when a plurality of the roadside objects are detected by the detection step;
A determination step of determining whether the roadside object detected in the detection step includes a registered roadside object registered in the map;
When the determination step determines that the registered roadside object is not included, the relative position recorded by the position recording step is the same as the roadside object detected at the present time. An estimated position calculating step for calculating an estimated position of the registered roadside object based on the relative position and the relative position of the registered roadside object;
A vehicle position specifying step for specifying a vehicle position on the map based on a result of aligning the calculated estimated position and a position of the registered roadside object on the map; Method.

Images