Vehicle position estimation device, vehicle position estimation method, and computer program

Abstract

To estimate vehicle positions with good accuracy.SOLUTION: A vehicle position estimation device 100, 100a-100h comprise: a reflection intensity acquisition unit 12 for identifying a plurality of detection points and acquiring detected reflection intensity from an onboard sensor 200 that detects reflection intensity at each of the plurality of detection points; a correction unit 13 for correcting reflection intensity at a road detection point so that a difference in reflection intensity arising from a difference in distance from a vehicle becomes smaller; and a position estimation unit 14 for comparing a reflection intensity map 31, in which at least a plurality of points and reflection intensity at the plurality of points are preliminarily stored in association, with the reflection intensity at the plurality of detection points that includes reflection intensity after correction so as to estimate the position of the vehicle.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] FIELD This disclosure relates to estimating vehicle position. [Background technology]

[0002] With the recent development of automatic driving technology for vehicles, various methods for estimating the position of a vehicle have been proposed. Patent Document 1 discloses a method for estimating the position of a vehicle by irradiating a beam from a radar device to the front or surroundings of the vehicle, identifying the position (distance and direction) of a detection point (also called a target) from the reflected wave, and comparing the identified position of the detection point with data previously stored in association with fixed objects and positions. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Patent No. 3848431 Summary of the Invention [Problem to be solved by the invention]

[0004] In the vehicle position estimation method of Patent Document 1, the vehicle position is estimated based on the positions of detection points detected by reflected waves, but there is still room for improvement, and a technology that can estimate the vehicle position with high accuracy is desired. [Means for solving the problem]

[0005] (1)According to one embodiment of the present disclosure, there is provided a vehicle position estimation device that is mounted on a vehicle and used to estimate a position of the vehicle, the vehicle position estimation device including: a reflection intensity acquisition unit that acquires the detected reflection intensity from an on-board sensor that identifies a plurality of detection points by irradiating electromagnetic waves and receiving reflected waves of the electromagnetic waves, and detects a reflection intensity, which is a reception intensity of the reflected wave at each of the plurality of detection points, a correction unit that corrects the reflection intensity at a road detection point that is a detection point corresponding to a road among the plurality of detection points so as to reduce a difference in the reflection intensity caused by a difference in distance, and a position estimation unit that estimates the position of the vehicle by comparing a reflection intensity map that previously associates at least a plurality of points with the reflection intensities at the plurality of points and stores the reflection intensities with each other, with the reflection intensities at the plurality of detection points including the reflection intensities corrected by the correction unit. and a first slope identification unit (15) that identifies, among the road detection points, a set of road detection points whose reflection intensity after correction by the correction unit differs by a predetermined amount or more from the reflection intensity at other road detection points after correction by the correction unit as a slope (SL1), and the reflection intensity map stores positions of the slopes in advance, and the position estimation unit compares the position of the slope identified by the first slope identification unit with the position of the slope in the reflection intensity map, and corrects a positional deviation of the vehicle along the longitudinal direction of the vehicle using a result of the comparison. . (2) As another aspect of the present disclosure, there is provided a vehicle position estimation device that is mounted on a vehicle and used to estimate a position of the vehicle. This vehicle position estimation device includes a reflection intensity acquisition unit that acquires the detected reflection intensity from an on-board sensor that identifies a plurality of detection points by irradiating electromagnetic waves and receiving reflected waves of the electromagnetic waves, and detects a reflection intensity, which is a reception intensity of the reflected wave at each of the plurality of detection points, a correction unit that corrects the reflection intensity at a road detection point that is a detection point corresponding to a road among the plurality of detection points so as to reduce a difference in the reflection intensity caused by a difference in distance, and estimates the position of the vehicle by comparing a reflection intensity map that previously associates at least a plurality of points with the reflection intensities at the plurality of points and stores the reflection intensities with each other, with the reflection intensities at the plurality of detection points including the reflection intensities corrected by the correction unit. the reflection intensity map includes a position estimation unit which estimates the reflection intensity of the road detection points by correcting the reflection intensity at the road detection points by a predetermined amount or more, and further includes an unevenness identification unit (16) which identifies a set of road detection points, among the road detection points, where the reflection intensity after correction by the correction unit differs by a predetermined amount or more compared to the reflection intensity at other road detection points after correction by the correction unit, and where the set has a size in a planar view that is equal to or smaller than a predetermined amount, as a concave or convex portion (PR0), and the reflection intensity map has positions of the concave and convex portions stored in advance, and the position estimation unit compares the position of the concave or convex portion identified by the unevenness identification unit with the position of the concave or convex portion in the reflection intensity map, and corrects a position shift of the vehicle along the longitudinal direction of the vehicle using a result of the comparison. (3) As another aspect of the present disclosure, there is provided a vehicle position estimation device that is mounted on a vehicle and used to estimate a position of the vehicle. The vehicle position estimation device includes a reflection intensity acquisition unit that acquires the detected reflection intensity from an on-board sensor that identifies a plurality of detection points by irradiating electromagnetic waves and receiving reflected waves of the electromagnetic waves, and detects a reflection intensity, which is a reception intensity of the reflected wave at each of the plurality of detection points, a correction unit that corrects the reflection intensity at a road detection point that is a detection point corresponding to a road among the plurality of detection points so that a difference in the reflection intensity caused by a difference in distance is reduced, and a position estimation unit that estimates the position of the vehicle by comparing a reflection intensity map that previously associates at least a plurality of points with the reflection intensities at the plurality of points and stores the reflection intensities with each other, and the reflection intensities of the plurality of detection points including the reflection intensities corrected by the correction unit, and the reflection intensity map stores a position of a fence in advance, and the position estimation unit compares the position of the fence identified by the fence identification unit with the position of the fence in the reflection intensity map and corrects a position shift of the vehicle along the longitudinal direction of the vehicle using a result of the comparison. (4) As another aspect of the present disclosure, there is provided a vehicle position estimation device that is mounted on a vehicle and used to estimate the position of the vehicle. The vehicle position estimation device includes a reflection intensity acquisition unit that acquires the detected reflection intensity from an on-board sensor that irradiates electromagnetic waves and receives reflected waves of the electromagnetic waves to identify multiple detection points and detects a reflection intensity, which is the reception intensity of the reflected wave at each of the multiple detection points, a correction unit that corrects the reflection intensity at a road detection point that is a detection point corresponding to a road among the multiple detection points so as to reduce a difference in the reflection intensity caused by a difference in distance, and a reflection intensity map that previously associates at least multiple points with the reflection intensities at the multiple points and stores them, and the reflection intensities of the multiple detection points including the reflection intensities corrected by the correction unit are compared to estimate the position of the vehicle. a reflection intensity distribution acquisition unit that acquires a distribution of the reflection intensity for each distance from the vehicle, and a lane number determination unit (19) that determines, in the acquired distribution, the number of pairs of reflection intensity peaks (p11-p13, p21-p23, p31-p33) that are spaced apart from each other in the width direction of the vehicle and have a reflection intensity equal to or greater than a predetermined magnitude, as the number of lanes, wherein lanes are pre-stored in the reflection intensity map, and the position estimation unit compares the number of lanes identified by the lane number determination unit with the number of lanes in the reflection intensity map and corrects the positional deviation of the vehicle along the longitudinal direction of the vehicle using a result of the comparison. (5) As another aspect of the present disclosure, there is provided a vehicle position estimation device that is mounted on a vehicle and used to estimate a position of the vehicle. The vehicle position estimation device includes a reflection intensity acquisition unit that acquires the detected reflection intensity from an on-board sensor that identifies a plurality of detection points by irradiating electromagnetic waves and receiving reflected waves of the electromagnetic waves, and detects a reflection intensity, which is a reception intensity of the reflected wave at each of the plurality of detection points, a correction unit that corrects the reflection intensity at a road detection point that is a detection point corresponding to a road among the plurality of detection points so as to reduce a difference in the reflection intensity caused by a difference in distance, and a position estimation unit that estimates the position of the vehicle by comparing a reflection intensity map that previously associates at least a plurality of points with the reflection intensities at the plurality of points and stores the reflection intensities with each other, with the reflection intensities at the plurality of detection points including the reflection intensities corrected by the correction unit. a reflection intensity distribution acquisition unit (11) that acquires a distribution of the reflection intensity for each distance from the vehicle, and a curve identification unit (41) that identifies, in the acquired distribution, a portion where a pair of reflection intensity peaks (p11-p13, p21-p23, p31-p33) that are located apart from each other in the width direction of the vehicle and have a reflection intensity equal to or greater than a predetermined magnitude shift to the left or right over time, as a curve, wherein the reflection intensity map has a position of the curve stored in advance, and the position estimation unit compares the position of the curve identified by the curve identification unit with the position of the curve in the reflection intensity map, and corrects the position deviation of the vehicle along the longitudinal direction of the vehicle using a result of the comparison. (6) As another aspect of the present disclosure, there is provided a vehicle position estimation device that is mounted on a vehicle and used to estimate a position of the vehicle, the vehicle position estimation device including: a reflection intensity acquisition unit that acquires the detected reflection intensity from an on-board sensor that identifies a plurality of detection points by irradiating electromagnetic waves and receiving reflected waves of the electromagnetic waves, and detects a reflection intensity, which is a reception intensity of the reflected wave at each of the plurality of detection points; a correction unit that corrects the reflection intensity at a road detection point that is a detection point corresponding to a road among the plurality of detection points, so that a difference in the reflection intensity caused by a difference in distance is reduced; and a position estimation unit that estimates the position of the vehicle by comparing a reflection intensity map that previously associates at least a plurality of points with the reflection intensities at the plurality of points and stores the reflection intensities with each other, with the reflection intensities at the plurality of detection points including the reflection intensities corrected by the correction unit; The system further includes a reflection intensity distribution acquisition unit (11) that acquires a distribution of the reflection intensity for each distance from the vehicle, and a second slope identification unit (42) that identifies, in the acquired distribution, a portion where the length between a pair of reflection intensity peaks (p41-p42, p51-p52, p61-p62) that are located apart from each other in the width direction of the vehicle and have a reflection intensity equal to or greater than a predetermined magnitude increases or decreases over time, as a slope, wherein the reflection intensity map has positions of the slopes stored in advance, and the position estimation unit compares the position of the slope identified by the second slope identification unit with the position of the slope in the reflection intensity map, and uses the result of the comparison to correct the positional deviation of the vehicle along the longitudinal direction of the vehicle.

[0006] According to the vehicle position estimation device of this embodiment, the vehicle position is estimated by comparing the reflection intensity detected by the on-board sensor with the reflection intensity map, so that the vehicle position can be estimated with high accuracy. In addition, the reflection intensity to be compared with the reflection intensity map is the reflection intensity obtained by correcting the reflection intensity at the road detection point so that the difference in reflection intensity caused by the difference in distance is reduced, so that it is possible to suppress comparison with the reflection intensity map using unevenness in reflection intensity on the road, such as unevenness in reflection intensity caused by different distances or unevenness in reflection intensity caused by low flatness of the road, as a feature point. Therefore, it is possible to suppress a decrease in the accuracy of position estimation due to the occurrence of a pattern similar to the reflection intensity pattern stored in the reflection intensity map by chance due to unevenness in reflection intensity on the road.

[0007] The present disclosure may be realized in various forms, for example, in the form of a vehicle position estimation method, a vehicle position estimation device, a computer program for realizing the vehicle position estimation method, a non-transitory recording medium on which such a computer program is recorded, etc. [Brief description of the drawings]

[0008] [Figure 1] 1 is a block diagram showing a schematic configuration of a vehicle position estimation device according to an embodiment of the present disclosure. [Diagram 2] 5 is a flowchart showing the procedure of a correction table creation process in the first embodiment. [Diagram 3] FIG. 4 is an explanatory diagram showing an example of the setting contents of a correction table. [Figure 4] 5 is a flowchart showing a procedure of a vehicle position estimation process in the first embodiment. [Diagram 5] FIG. 11 is an explanatory diagram showing an example of correction of reflection intensity. [Figure 6] FIG. 11 is a block diagram showing a schematic configuration of a vehicle position estimation device according to a second embodiment. [Figure 7] 10 is a flowchart showing the procedure of a vehicle position estimation process in a second embodiment. [Figure 8] FIG. 13 is an explanatory diagram illustrating an example of positional deviation of a characteristic portion in the second embodiment. [Figure 9] FIG. 11 is a block diagram showing a schematic configuration of a vehicle position estimation device according to a third embodiment. [Figure 10] 13 is a flowchart showing the procedure of a vehicle position estimation process in the third embodiment. [Figure 11] FIG. 13 is an explanatory diagram illustrating an example of a positional deviation of a slope portion in the third embodiment. [Figure 12] FIG. 13 is a block diagram showing a schematic configuration of a vehicle position estimation device according to a fourth embodiment. [Figure 13] 13 is a flowchart showing a procedure of a vehicle position estimation process in a fourth embodiment. [Figure 14] FIG. 13 is an explanatory diagram illustrating an example of misalignment of a recess or a portion in the fourth embodiment. [Figure 15]FIG. 13 is a block diagram showing a schematic configuration of a vehicle position estimation device according to a fifth embodiment. [Figure 16] FIG. 13 is an explanatory diagram showing an example of a reflection intensity distribution after correction in the fifth embodiment. [Figure 17] 13 is a flowchart showing the procedure of a vehicle position estimation process in the fifth embodiment. [Figure 18] FIG. 13 is an explanatory diagram showing an enlarged portion of the reflection intensity distribution after correction in the fifth embodiment. [Figure 19] FIG. 13 is a block diagram showing a schematic configuration of a vehicle position estimation device according to a sixth embodiment. [Figure 20] FIG. 23 is an explanatory diagram showing an example of a reflection intensity distribution after correction in the sixth embodiment. [Figure 21] FIG. 23 is an explanatory diagram illustrating a schematic view of a part of a reflection intensity distribution in the sixth embodiment. [Figure 22] 13 is a flowchart showing the procedure of a vehicle position estimation process in the sixth embodiment. [Diagram 23] FIG. 13 is a block diagram showing a schematic configuration of a vehicle position estimation device according to a seventh embodiment. [Figure 24] FIG. 23 is an explanatory diagram showing an example of a partial change over time in a reflection intensity distribution in the seventh embodiment. [Diagram 25] 23 is a flowchart showing the procedure of a vehicle position estimation process in the seventh embodiment. [Figure 26] FIG. 13 is a block diagram showing a schematic configuration of a vehicle position estimation device according to an eighth embodiment. [Figure 27] FIG. 23 is an explanatory diagram showing an example of a change over time in a portion of a reflection intensity distribution in the eighth embodiment. [Figure 28] 23 is a flowchart showing the procedure of a vehicle position estimation process in the eighth embodiment. [Figure 29] FIG. 13 is a block diagram showing a schematic configuration of a vehicle position estimation device according to a ninth embodiment. [Diagram 30] 13 is a flowchart showing a procedure of a vehicle position estimation process in the ninth embodiment. [Diagram 31] FIG. 23 is an explanatory diagram showing a schematic example of a positional deviation of a marker in the ninth embodiment. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0009] A. First embodiment: A1. Equipment configuration: 1 is mounted on a vehicle and used to estimate the position of the vehicle. The vehicle position estimation device 100 is electrically connected to an on-board sensor 200 and a driving assistance control device 300.

[0010] The on-vehicle sensor 200 irradiates electromagnetic waves ahead of and around the vehicle, receives the reflected waves, and thereby identifies a plurality of detection points (also called targets), and detects the reception intensity (hereinafter called "reflection intensity") of the reflected waves at each detection point. The electromagnetic waves irradiated by the on-vehicle sensor 200 include, for example, millimeter waves (radio waves with a frequency of about 30 to 300 GHz) and infrared lasers. Therefore, the on-vehicle sensor 200 is also called a millimeter wave radar or Lidar (light detection and ranging) device. As will be described later, the vehicle position estimation device 100 estimates the position of the vehicle by using the reflection intensity at the detection points detected by the on-vehicle sensor 200. When the on-vehicle sensor 200 is powered on, it repeatedly irradiates electromagnetic waves and receives reflected waves while scanning ahead and around the vehicle. The on-vehicle sensor 200 also identifies the detection points by using the received reflected waves. Specifically, the on-vehicle sensor 200 identifies the distance and angle of each detection point by using the reflected waves. The distance is determined by multiplying the time from the emission of electromagnetic waves to the reception of the reflected waves as the round-trip time (Time To Flight) from the vehicle (on-board sensor 200) to the detection point by half the speed of light.

[0011] The vehicle position estimation device 100 notifies the driving assistance control device 300 of the estimated vehicle position information. The driving assistance control device 300 performs driving assistance for the vehicle based on the vehicle position information received from the vehicle position estimation device 100. "Driving assistance" means automatically executing engine control, brake control, and steering control of the vehicle in place of the driver, or executing them to assist the driver's control. "Executing them to assist the driver's control" corresponds to automatically executing engine control, brake control, and steering control so that the vehicle moves to the right when the driver turns on the right turn signal to change lanes while the vehicle is traveling straight. The vehicle position estimation device 100 is configured, for example, by an ECU (Electric Control Unit). The driving assistance control device 300 may perform automatic driving of the vehicle instead of performing driving assistance.

[0012] The vehicle position estimation device 100 is configured by a computer including a CPU 10, a RAM 20, and an EEPROM (Electrically Erasable Programmable Read-Only Memory) 30. The CPU 10, the RAM 20, and the EEPROM 30 are each connected to an internal bus 90 and configured to be able to communicate with each other via the internal bus 90. The CPU 10 functions as a correction table generation unit 9, a reflection intensity acquisition unit 11, a correction unit 12, and a position estimation unit 13 by expanding a computer program stored in advance in the EEPROM 30 into the RAM 20 and executing it. The correction table generation unit 9 generates a correction table 32 described later by executing a correction table generation process described later. The reflection intensity acquisition unit 11 acquires the reflection intensity of each detection point detected by the vehicle-mounted sensor 200. The correction unit 12 corrects the reflection intensity at a detection point corresponding to a road (hereinafter referred to as a "road detection point") among the detection points. Specifically, the reflection intensity at the road detection points is corrected so that the difference in reflection intensity between road detection points caused by the difference in distance from the vehicle (hereinafter also simply referred to as "distance") is reduced. Details of such correction will be described later. The position estimation unit 13 estimates the position of the vehicle by comparing the reflection intensities of the road detection points corrected by the correction unit 12 and the reflection intensities of the other detection points with a reflection intensity map 31 described later.

[0013] The EEPROM 30 stores a reflection intensity map 31 and a correction table 32. The reflection intensity map 31 stores a large number of points (targets) in association with the reflection intensity at each point. The reflection intensity map 31 is created in advance by, for example, irradiating electromagnetic waves and receiving the reflected waves while a probe car is traveling on various roads, and the points (targets) obtained by this are associated with the reflection intensity, and is stored in the EEPROM 30. The reflection intensity map 31 is also called three-dimensional map data. The correction table 32 consists of a plurality of pairs of distance from the vehicle and reflection intensity. In FIG. 3, these pairs are represented by black circles. As shown in FIG. 3, the correction table 32 sets the reflection intensity of a representative point for each predetermined distance range. As is clear from a comparison of the pairs, the reflection intensity decreases as the distance increases, that is, as the distance increases from the vehicle. The correction table 32 is obtained as a result of executing a correction table creation process described later, and is stored in the EEPROM 30.

[0014] The vehicle is equipped with a navigation system that uses a Global Navigation Satellite System (GNSS) such as a Global Positioning System (GPS) in addition to the above-mentioned vehicle position estimation device 100, the in-vehicle sensor 200, and the driving assistance control device 300. The navigation system identifies the approximate position of the vehicle, and the vehicle position estimation device 100 identifies the exact position.

[0015] A2.Correction table creation process: When a user performs a predetermined operation in the vehicle, the correction table generating unit 9 executes the correction table creation process shown in Fig. 2. In this embodiment, the "predetermined operation" corresponds to an operation of pressing a "correction table creation execution button" on a predetermined menu screen displayed on a display arranged on the instrument panel. Note that the correction table creation process may be executed in response to any other type of operation, not limited to the above operation.

[0016] As shown in FIG. 2, the correction table generating unit 9 judges whether the vehicle is stopped (step S105). If it is judged that the vehicle is not stopped (step S105: NO), step S105 is executed again. That is, the correction table generating unit 9 waits until the vehicle is stopped. If it is judged that the vehicle is stopped (step S105: YES), the correction table generating unit 9 acquires the reflection intensity of the reflected wave from the flat road ahead (step S110). The correction table generating unit 9 judges whether the number of repeated acquisitions of the reflection intensity of the flat road ahead has reached a threshold number (step S115). If it is judged that the acquisition number has not reached the threshold number (step S115: NO), the process returns to the above-mentioned step S110. Therefore, in this case, the reflection intensity of the flat road ahead is acquired again.

[0017] When it is determined that the number of times the reflection intensity of a flat road has been acquired has reached the threshold number of times (step S115: YES), the correction table generating unit 9 averages the reflection intensity for each distance and updates the correction table (step S120). "For each distance" means a distance range of a predetermined width, for example, for each distance range of 20 m (meters). In step S120, the reflection intensity of the detection points (road detection points) detected in each distance range is averaged, and the average distance of the distance range and the reflection intensity obtained by averaging are registered in the correction table 32 as a pair. In this way, the correction table 32 as shown in FIG. 3 is set. Note that if the correction table 32 has already been saved before the correction table generating process is started, the correction table 32 is overwritten as a result of the correction table generating process.

[0018] A3. Vehicle position estimation process: The vehicle position estimation process shown in Fig. 4 is a process for estimating the position of the vehicle. The vehicle position estimation process is executed when the ignition of the vehicle is turned on. Note that, before the vehicle position estimation process is executed, the above-mentioned correction table creation process is executed, and the correction table 32 is stored in the EEPROM 30.

[0019] The reflection intensity acquisition unit 11 acquires the reflection intensity of each detection point detected by the vehicle-mounted sensor 200 (step S205). The correction unit 12 corrects the reflection intensity at the road detection point, among the reflection intensities acquired in step S205, using the reflection intensity map 31 (step S210). The road detection point is identified by discriminating it from other detection points based on, for example, the distance and angle of the detection point and the reflection intensity. The correction in step S210 is specifically performed as follows. When the reflection intensity I of the road detection point at a position at a distance R from the vehicle is acquired, the correction unit 12 calculates the corrected reflection intensity Icalib by the following formula (1). Icalib = (Iref / α) × I (1) In the above formula (1), Iref indicates a predetermined reference reflection intensity Iref that serves as a reference for the reflection intensity on the road, and α indicates a correction coefficient α calculated by the following formula (2). α=[(i1-i0) / (r1-r0)]×(R-r0)+i0 ···(2) In the above formula (2), r0 and r1 indicate different distances from the vehicle, and i0 and i1 indicate reflection intensity. Both r0 and i0 and r1 and i1 are pairs included in a plurality of pairs of "distance" and "reflection intensity" in the correction table 32, and the magnitude of the distance R is the magnitude between the distance r0 and the distance r1. Specifically, the distance R is the distance sandwiched between the two distances r0 and r1 of the first pair (r0, i0) and the second pair (r1, i1) shown in FIG. 3, and the correction coefficient α corresponds to the reflection intensity of the point interpolated from the first pair and the second pair.

[0020] As described above, in the correction table 32, the reflection intensity decreases as the distance increases. Therefore, the correction coefficient α decreases as the distance R increases, and "Iref / α" in the above formula (1) increases. Therefore, the ratio of the corrected reflection intensity Icalib to the pre-correction reflection intensity I increases as the distance increases. For this reason, on a flat road, the reflection intensity generally decreases as the distance increases, but the above correction suppresses the variation in reflection intensity according to distance, and the reflection intensity at the road detection point becomes approximately uniform.

[0021] The reflection intensity image F1a shown in the upper part of FIG. 5 is an image in which the reflection intensity before the correction in step S210 is expressed by shading. The reflection intensity image F1b shown in the lower part of FIG. 5 is an image in which the reflection intensity after the correction in step S210 is expressed by shading. In the two reflection intensity images F1a and F1b, lighter (brighter) parts indicate a higher reflection intensity than darker (darker) parts. The two reflection intensity images F1a and F1b are images obtained while traveling on a road with multiple lanes including a first lane L1, a second lane L2, and a third lane L3. A fence Fe1 is provided ahead between the second lane L2 and the third lane L3. An uphill slope SL1 is formed in the part of the third lane L3 and the lane next to it, which corresponds to the position where the fence Fe1 is provided. In the reflection intensity image F1b, a line is also shown as a guide for the distance from the vehicle. Specifically, three lines are shown indicating three distances from the vehicle: 20 m, 40 m, and 60 m.

[0022] In the reflection intensity image F1a, the reflection intensity of the road decreases as the distance increases in each of the lanes L1 to L3. In contrast, in the reflection intensity image F1b, the reflection intensity of the road is approximately the same at least within a distance range of 60 m from the vehicle. The reason why the reflection intensities of the road detection points are made approximately the same is to prevent unevenness in reflection intensity caused by different distances between the road detection points or unevenness in reflection intensity caused by low flatness of the road from being mistaken for structures other than roads.

[0023] As shown in FIG. 4, after completing step S210, the position estimation unit 13 compares the reflection intensity map 31 with the reflection intensity (reflection intensity pattern) acquired in step S205 including the corrected reflection intensity (step S215), and determines whether the correlation value is equal to or greater than a threshold (step S220). The correlation value of the reflection intensity can be obtained by any known method. For example, at each position (angle), the difference between the reflection intensity acquired in step S205 and the reflection intensity set in the reflection intensity map 31 is obtained, and the correlation value may be calculated using an arithmetic expression that obtains a larger correlation value as the difference is smaller. At this time, candidates for the reflection intensity pattern in the reflection intensity map 31 may be narrowed down based on a rough vehicle position specified in advance by a navigation device (not shown), and these candidates may be compared with the reflection intensity acquired by the vehicle-mounted sensor 200 as comparison targets.

[0024] If it is determined that the correlation value is not equal to or greater than the threshold (step S220: NO), the process returns to step S205 described above. Therefore, in this case, estimation of the vehicle position is not performed. On the other hand, if it is determined that the correlation value is equal to or greater than the threshold (step S220: YES), a deviation between the position recognized by the vehicle-mounted sensor 200 and the actual position (position identified by the reflection intensity map 31) is identified (step S225). Specifically, a position deviation of the reflection intensity group recognized by the vehicle-mounted sensor 200 with respect to the reflection intensity group in the reflection intensity map 31 in which the correlation value is recognized to be equal to or greater than the threshold is identified. The position in the width direction on the road on which the probe car traveled when the reflection intensity map 31 was generated and the position in the width direction (hereinafter also simply referred to as the "width direction") of the vehicle on the road when the vehicle actually travels may deviate from each other, and in this case, it is identified as a position deviation in the width direction. In addition, due to differences in the installation positions in the height direction and the vehicle length direction between the sensor attached to the probe car when the reflection intensity map 31 was generated and the sensor of the reflection intensity map 31, this is identified as a positional deviation in the height direction and the vehicle length direction (hereinafter also simply referred to as the "length direction").

[0025] The position estimation unit 13 corrects the position deviation identified in step S225 (step S230). Specifically, the position identified by the navigation system (GNSS) as the current position of the vehicle is corrected so as to cancel the position deviation identified in step S225. In this manner, the current position of the vehicle is estimated. After completion of step S230, the process returns to step S205.

[0026] According to the vehicle position estimation device 100 of the first embodiment described above, the vehicle position is estimated by comparing the reflection intensity detected by the on-board sensor 200 with the reflection intensity map 31, so that the vehicle position can be estimated with high accuracy. The reflection intensity to be compared with the reflection intensity map 31 is the reflection intensity obtained by correcting the reflection intensity at the road detection point so that the difference in reflection intensity caused by the difference in distance is reduced. Therefore, it is possible to suppress comparison with the reflection intensity map 31 as a feature point of unevenness in reflection intensity on the road, that is, unevenness in reflection intensity caused by different distances and unevenness in reflection intensity caused by low flatness of the road. Therefore, it is possible to suppress a decrease in the accuracy of position estimation due to the occurrence of a pattern similar to the reflection intensity pattern stored in the reflection intensity map 31 by chance due to unevenness in reflection intensity on the road.

[0027] Furthermore, since the corrected reflection intensity Icalib is obtained by the above formula (1), the reflection intensity at the road detection point can be accurately corrected so that the difference in reflection intensity caused by the difference in distance is reduced.

[0028] B. Second embodiment: A vehicle position estimation device 100a of the second embodiment shown in Fig. 6 differs from the vehicle position estimation device 100 of the first embodiment shown in Fig. 1 in that the CPU 10 also functions as a feature part identification unit 14. Other configurations of the vehicle position estimation device 100a of the second embodiment are similar to those of the vehicle position estimation device 100 of the first embodiment, so the same components are denoted by the same reference numerals and detailed description thereof will be omitted.

[0029] The characteristic part identification unit 14 identifies continuous characteristic parts (hereinafter, simply referred to as "characteristic parts") along the traveling direction of the vehicle. Examples of characteristic parts include boundaries between lanes, boundaries between roads and sidewalks, lines constituting centerlines (generally white lines in Japan), curbs, wheel tracks, and the like.

[0030] In this embodiment, the reflection intensity map 31 stores a large number of points in association with the reflection intensity at each point, and also stores the positions of characteristic portions in advance.

[0031] The vehicle position estimation process in the second embodiment shown in Fig. 7 differs from the vehicle position estimation process in the first embodiment shown in Fig. 4 in that steps S211 and S212 are additionally executed, and step S215a is executed instead of step S215. Since the other steps of the vehicle position estimation process in the second embodiment are the same as those in the first embodiment, the same steps are denoted by the same reference numerals, and detailed descriptions thereof will be omitted.

[0032] After completion of step S210, the feature identifying unit 14 searches for feature parts from the reflection intensities acquired in step S205, including the corrected reflection intensities (step S211). For example, white lines and curbs can be detected by searching for a set of detection points that have a reflection intensity greater than the reflection intensities of surrounding road detection points by a predetermined or more, and that continue in the direction of travel of the vehicle. Also, for example, ruts can be detected by searching for a set of detection points that have a reflection intensity smaller than the reflection intensities of surrounding road detection points by a predetermined or more, and that continue in the direction of travel of the vehicle.

[0033] The position estimation unit 13 determines whether or not a characteristic portion has been detected (step S212), and if it is determined that a characteristic portion has not been detected (step S212: NO), the process returns to step S205. On the other hand, if it is determined that a characteristic portion has been detected (step S212: YES), the position estimation unit 13 compares the characteristic portion of the reflection intensity map 31 with the detected characteristic portion (step S215a). After completion of step S215a, the above-mentioned steps S220 to S230 are executed. In this embodiment, the position deviation identified in step S225 and corrected in step S230 is mainly a position deviation in the width direction of the vehicle. This will be described with reference to FIG. 8.

[0034] In FIG. 8, a vehicle VL1 equipped with a vehicle position estimation device 100a is traveling on a first lane L1. In FIG. 8, a pair of white lines WL1 and WL2 shown by dashed lines and a pair of white lines WL11 and WL12 shown by solid lines are white lines that define the boundaries of the first lane L1, and are extended in the length direction D1 of the vehicle and are arranged at a predetermined distance from each other in the width direction D2 of the vehicle. The pair of white lines WL1 and WL2 shown by dashed lines indicate a characteristic portion recognized by the on-vehicle sensor 200, that is, a pair of white lines. On the other hand, the pair of white lines WL11 and WL12 shown by solid lines indicate a characteristic portion stored in the reflection intensity map 31, that is, a pair of white lines. Note that the "length direction D1" and "width direction D2" in the following other embodiments correspond to the length direction D1 and width direction D2 of this embodiment.

[0035] 8, a positional deviation Δw1 in the width direction D2 is identified by comparing a pair of white lines WL1 and WL2 with a pair of white lines WL11 and WL12. Then, the current position of the vehicle is corrected and estimated so as to cancel the positional deviation Δw1.

[0036] The vehicle position estimation device 100a of the second embodiment described above has the same effects as the vehicle position estimation device 100 of the first embodiment. In addition, the positions of characteristic parts identified using the reflection intensities of a plurality of detection points are compared with the positions of characteristic parts identified from a reflection intensity map, and the positional deviation of the vehicle VL1 along the width direction D2 of the vehicle VL1 is corrected using the comparison result, so that the positional deviation of the vehicle VL1 along the width direction D2 can be corrected with high accuracy.

[0037] C. Third embodiment: A vehicle position estimation device 100b of the third embodiment shown in Fig. 9 differs from the vehicle position estimation device 100 of the first embodiment shown in Fig. 1 in that the CPU 10 also functions as a first slope identification unit 15. Other configurations of the vehicle position estimation device 100b of the third embodiment are similar to those of the vehicle position estimation device 100 of the first embodiment, so the same components are denoted by the same reference numerals and detailed description thereof will be omitted.

[0038] The first slope identifying unit 15 identifies an uphill or downhill portion (hereinafter referred to as a "slope"). In this embodiment, the reflection intensity map 31 stores a large number of points in association with the reflection intensity at each point, and also stores the positions of the slopes in advance.

[0039] The vehicle position estimation process in the third embodiment shown in Fig. 10 differs from the vehicle position estimation process in the first embodiment shown in Fig. 4 in that steps S211b and S212b are additionally executed, and step S215b is executed instead of step S215. Since the other steps of the vehicle position estimation process in the second embodiment are the same as those in the first embodiment, the same steps are denoted by the same reference numerals, and detailed descriptions thereof will be omitted.

[0040] After completion of step S210, the first slope identification unit 15 searches for a slope from the reflection intensity acquired in step S205 including the corrected reflection intensity (step S211b). For example, a portion where the reflection intensity is greater than a predetermined magnitude compared to other road detection points and continues in the width direction D2 of the vehicle and the traveling direction (length direction D1) of the vehicle is identified as an uphill slope. On the other hand, a portion where the reflection intensity is smaller than a predetermined magnitude compared to other road detection points and continues in the width direction D2 of the vehicle and the traveling direction (length direction D1) of the vehicle is identified as a downhill slope. Even if the reflection intensity is corrected in step S210, the reflection intensity of an uphill or downhill slope is originally significantly different from that of a flat road, so that the reflection intensity after correction is significantly different from the reflection intensity after correction for a flat road. For example, the reflection intensity of the uphill slope SL1 in the reflection intensity image F1b in FIG. 5 is greater than the reflection intensity of the surrounding road detection points.

[0041] The position estimation unit 13 judges whether or not a slope portion is detected (step S212b), and if it is judged that a slope portion is not detected (step S212b: NO), the process returns to step S205. On the other hand, if it is judged that a slope portion is detected (step S212b: YES), the position estimation unit 13 compares the feature portion of the reflection intensity map 31 with the detected feature portion (step S215b). After completion of step S215b, the above-mentioned steps S220 to S230 are executed. In this embodiment, the position deviation identified in step S225 and corrected in step S230 is mainly the position deviation in the longitudinal direction D1 of the vehicle. This will be described with reference to FIG. 11.

[0042] The left side of Fig. 11 shows the surroundings of the vehicle VL1 recognized by the on-board sensor 200. The right side of Fig. 11 shows the surroundings of the vehicle VL1 based on the information stored in the reflection intensity map 31. Fig. 11 shows a schematic plan view of the range shown in Fig. 5. Note that Fig. 11 also shows a fourth lane L4 in addition to the three lanes L1 to L3.

[0043] As shown on the left side of Fig. 11, the upslope SL1 is identified as being relatively far away in the length direction D1 (traveling direction) from the perspective of the vehicle VL1. In contrast, as shown on the right side of Fig. 12, the reflection intensity map 31 stores the upslope SL1 as being relatively close in the length direction D1 from the perspective of the vehicle VL1. Then, by comparing the upslope SL1 identified by the recognition result of the on-board sensor 200 with the upslope SL1 identified in the reflection intensity map 31, a positional deviation Δd1 in the length direction D1 is identified. The current position of the vehicle is then corrected and estimated so as to cancel this positional deviation Δd1.

[0044] The vehicle position estimation device 100b of the third embodiment described above has the same effect as the vehicle position estimation device 100 of the first embodiment. The inventors of the present application have found that at road detection points on a downhill slope, the reflection intensity after correction is smaller than the reflection intensity after correction at other road detection points (road detection points on a flat road, etc.) by a predetermined amount or more, and at road detection points on an uphill slope, the reflection intensity after correction is larger than the reflection intensity after correction at other road detection points (road detection points on a flat road, etc.) by a predetermined amount or more. Therefore, according to the vehicle position estimation device 100b of the third embodiment, a set of road detection points whose reflection intensity after correction differs from the reflection intensity after correction at other road detection points by a predetermined amount or more is identified as a slope, so that the slope can be identified with high accuracy. In addition, the slope is compared with the position of the slope in the reflection intensity map 31, and the position deviation Δd1 of the vehicle VL1 along the length direction D1 of the vehicle VL1 is corrected using the comparison result, so that the position of the vehicle VL1 in the length direction D1 can be estimated with high accuracy.

[0045] D. Fourth embodiment: A vehicle position estimation device 100c of the fourth embodiment shown in Fig. 12 differs from the vehicle position estimation device 100 of the first embodiment shown in Fig. 1 in that the CPU 10 also functions as a roughness identification unit 16. Other configurations of the vehicle position estimation device 100c of the fourth embodiment are similar to those of the vehicle position estimation device 100 of the first embodiment, so the same components are denoted by the same reference numerals and detailed description thereof will be omitted.

[0046] The unevenness identification unit 16 identifies depressions and protrusions on the road. A depression is a dent or the like that is recessed compared to the surrounding parts. A protrusion is a part that protrudes compared to the surrounding parts. The reflection intensity of these differs by a predetermined amount or more compared to the surrounding flat parts. Therefore, the reflection intensity after correction in step S210 also differs by a predetermined amount or more compared to other parts (flat parts). Specifically, the reflection intensity is smaller in a depression than in other parts, and the reflection intensity is larger in a protrusion than in other parts.

[0047] In this embodiment, the reflection intensity map 31 stores a large number of points in association with the reflection intensity at each point, and also stores the positions of the concave and convex portions in advance.

[0048] The vehicle position estimation process in the fourth embodiment shown in Fig. 13 differs from the vehicle position estimation process in the first embodiment shown in Fig. 4 in that steps S211c and S212c are additionally executed, and step S215c is executed instead of step S215. Since the other steps of the vehicle position estimation process in the fourth embodiment are the same as those in the first embodiment, the same steps are denoted by the same reference numerals, and detailed descriptions thereof will be omitted.

[0049] After completion of step S210, the unevenness identification unit 16 searches for a concave or convex part from the reflection intensity acquired in step S205 including the corrected reflection intensity (step S211c). Specifically, a set of road detection points whose corrected reflection intensity differs by a predetermined amount or more from the corrected reflection intensity at other road detection points and whose planar size is equal to or smaller than a predetermined size is identified as a concave or convex part. The "predetermined size" of the planar size described above is preset as a size that allows, for example, an uphill slope to be distinguished from a convex part, and that allows a downhill slope to be distinguished from a concave part.

[0050] The position estimation unit 13 judges whether or not a concave or convex portion is detected (step S212c), and if it is judged that a concave or convex portion is not detected (step S212c: NO), the process returns to step S205. On the other hand, if it is judged that a concave or convex portion is detected (step S212c: YES), the position estimation unit 13 compares the concave or convex portion in the reflection intensity map 31 with the detected concave or convex portion (step S215c). After completion of step S215c, the above-mentioned steps S220 to S230 are executed. In this embodiment, the position deviation identified in step S225 and corrected in step S230 is mainly a position deviation in the longitudinal direction D1 of the vehicle. This will be described with reference to FIG. 14.

[0051] In Fig. 14, a vehicle VL1 equipped with a vehicle position estimation device 100c is traveling in a first lane L1. A convex portion PR0 shown by a dashed line in Fig. 8 indicates a convex portion recognized by the on-board sensor 200. On the other hand, a convex portion PR1 shown by a solid line indicates a convex portion stored in the reflection intensity map 31.

[0052] 14, by comparing the convex portion PR0 with the convex portion PR1, the positional deviation Δd2 in the length direction D1 is identified. Then, the current position of the vehicle is corrected and estimated so as to cancel the positional deviation Δd2.

[0053] The vehicle position estimation device 100c of the fourth embodiment described above has the same effects as the vehicle position estimation device 100 of the first embodiment. Also, a set of road detection points that differ from the corrected reflection intensity by a predetermined size or more and whose size in a plan view is equal to or smaller than a predetermined size is identified as a concave or convex part, the position of the concave or convex part is compared with the position of the concave or convex part in the reflection intensity map 31, and the positional deviation Δd2 of the vehicle VL1 along the longitudinal direction D1 of the vehicle VL1 is corrected using the comparison result, so that the position of the vehicle VL1 in the longitudinal direction D1 can be estimated with high accuracy.

[0054] E. Fifth embodiment: A vehicle position estimation device 100d of the fifth embodiment shown in Fig. 15 differs from the vehicle position estimation device 100 of the first embodiment shown in Fig. 1 in that the CPU 10 also functions as a reflection intensity distribution acquisition unit 17 and a fence identification unit 18. Other configurations of the vehicle position estimation device 100d of the fifth embodiment are similar to those of the vehicle position estimation device 100 of the first embodiment, so the same components are denoted by the same reference numerals and detailed description thereof will be omitted.

[0055] The reflection intensity distribution acquisition unit 17 acquires the distribution of reflection intensity for each distance from the vehicle. "For each distance" has the same meaning as "for each distance" explained in the first embodiment. Furthermore, the distribution means the distribution in the width direction D2 of the vehicle. As shown in the lower part of FIG. 16, for example, the distribution of reflection intensity in the width direction D1 at positions at distances of 20 m, 40 m, and 60 m from the vehicle is acquired. Note that the reflection intensity image F1b shown in the upper part of FIG. 16 is the same as the reflection intensity image F1b shown in FIG. 5.

[0056] The fence identification unit 18 identifies a fence. The inventors of the present application have found that, in the distribution of reflection intensities beyond a certain distance, a fence, such as fence Fe1 shown in Fig. 17, is identified as a collection of detection points whose reflection intensities differ by a predetermined magnitude or more within a range of a predetermined length or less in a direction parallel to the vehicle's width direction D2 compared to those just before that distance. The fence Fe1 in Fig. 16 is shown brighter (having a higher reflection intensity) than those approximately 60 m away. Therefore, the fence identification unit 18 identifies such a portion as a fence.

[0057] In this embodiment, the reflection intensity map 31 stores a large number of points in association with the reflection intensity at each point, and also stores the position of the fence in advance.

[0058] The vehicle position estimation process in the fifth embodiment shown in Fig. 17 differs from the vehicle position estimation process in the first embodiment shown in Fig. 4 in that steps S211d and S212d are additionally executed, step S212d is executed instead of step S212, and step S215d is executed instead of step S215. Since the other steps of the vehicle position estimation process in the fifth embodiment are the same as those in the first embodiment, the same steps are denoted by the same reference numerals and detailed descriptions thereof will be omitted.

[0059] After completing step S210, the reflection intensity distribution acquisition unit 17 acquires the distribution of reflection intensity for each distance (step S211d). The fence identification unit 18 determines whether or not a fence pattern is present in the distribution of reflection intensity acquired in step S211d (step S212d).

[0060] FIG. 18 shows the distribution of reflection intensity at 20 m, 40 m, and 60 m in a range W10 in the width direction D1 where the fence Fe1 shown in FIG. 16 exists. In FIG. 18, the intensity distribution SD20 shown by the dashed line shows the reflection intensity distribution at a distance of 20 m. The intensity distribution SD40 shown by the thin solid line shows the reflection intensity distribution at a distance of 40 m. The intensity distribution SD60 shown by the thick solid line shows the reflection intensity distribution at a distance of 60 m. In the example shown in FIG. 18, in the range W10, there is a part where the reflection intensity is significantly different in the intensity distribution SD60 on the relatively far side compared to the two intensity distributions SD20 and SD40 on the relatively near side. Such a part corresponds to the fence Fe1 as shown in FIG. 16. In step S212d, a pattern as shown in FIG. 18 is searched for as a fence pattern.

[0061] As shown in Fig. 17, if it is determined that there is no fence pattern (step S212d: NO), the process returns to step S205. On the other hand, if it is determined that there is a fence pattern (step S212d: YES), the position estimation unit 13 compares the fence in the reflection intensity map 31 with the detected fence (step S215d). After completion of step S215d, the above-mentioned steps S220 to S230 are executed. In this embodiment, the position deviation identified in step S225 and corrected in step S230 is mainly the position deviation in the longitudinal direction D1 of the vehicle.

[0062] The vehicle position estimation device 100d of the fifth embodiment described above has the same effect as the vehicle position estimation device 100 of the first embodiment. The inventors of the present application have found that when a fence is provided, a set of detection points exists in which the reflection intensity differs by a predetermined amount or more in a range of a predetermined length or less in a direction parallel to the width direction in the distribution of reflection intensity at the portion where the fence is provided, compared to the distribution in front of the fence. Therefore, according to the vehicle position estimation device 100d of the fifth embodiment, the position of the fence can be identified with high accuracy. In addition, the position of the fence is compared with the position of the fence in the reflection intensity map 31, and the position deviation of the vehicle along the length direction D1 of the vehicle is corrected using the comparison result, so that the position of the vehicle in the length direction D1 can be estimated with high accuracy.

[0063] F. Sixth embodiment: A vehicle position estimation device 100e of the sixth embodiment shown in Fig. 19 differs from the vehicle position estimation device 100d of the fifth embodiment shown in Fig. 15 in that the CPU 10 functions as a lane number identification unit 19 instead of the fence identification unit 18. Other configurations of the vehicle position estimation device 100e of the sixth embodiment are similar to those of the vehicle position estimation device 100d of the fifth embodiment, so the same components are denoted by the same reference numerals and detailed description thereof will be omitted.

[0064] The lane number specifying unit 19 specifies the number of lanes at the current position of the vehicle. A method for specifying the number of lanes by the lane number specifying unit 19 will be described with reference to Figs. 20 and 21.

[0065] The lane number determination unit 19 determines each lane in the width direction D2 from the corrected reflection intensity distribution for each distance. For example, lane L1 is sandwiched between two parallel white lines as shown in Fig. 20. These two white lines form a predetermined pattern in the reflection intensity distribution for each distance.

[0066] Fig. 21 shows a schematic representation of a portion of the distribution of reflection intensity at each distance. In Fig. 21, the dashed line shows the distribution of reflection intensity at a distance of 20 m. The thin solid line shows the distribution of reflection intensity at a distance of 40 m. The thick solid line shows the distribution of reflection intensity at a distance of 60 m.

[0067] In the portion where the two white lines are parallel, a pair of reflection intensity mountains (peaks) having reflection intensity of a predetermined magnitude or more appear at a predetermined distance apart in the width direction D2. For example, in the example of FIG. 21, peaks p11 and p12 appear in the intensity distribution at a distance of 60 m. Similarly, peaks p21 and p22 appear in the intensity distribution at a distance of 40 m, and peaks p31 and p32 appear in the intensity distribution at a distance of 20 m. In this case, the area between the pair of peaks (mountains) is identified as one lane. In the example of FIG. 21, further, peaks p12 and p13 appear in the intensity distribution at a distance of 60 m. Similarly, peaks p22 and p23 appear in the intensity distribution at a distance of 40 m, and peaks p32 and p33 appear in the intensity distribution at a distance of 20 m. Therefore, the area between these peaks (mountains) is also identified as one lane. Therefore, in the example of FIG. 21, the number of lanes is identified as "2".

[0068] In this embodiment, the reflection intensity map 31 stores a large number of points in association with the reflection intensity at each point, and also stores each lane in advance.

[0069] The vehicle position estimation process in the sixth embodiment shown in Fig. 22 differs from the vehicle position estimation process in the fifth embodiment shown in Fig. 17 in that step S212e is executed instead of step S212d, and step S215e is executed instead of step S215d. Since the other steps of the vehicle position estimation process in the sixth embodiment are the same as those in the fifth embodiment, the same steps are denoted by the same reference numerals, and detailed descriptions thereof will be omitted.

[0070] After the distribution of reflection intensity for each distance is acquired in step S211d, the lane number identification unit 19 determines whether or not there is a lane pattern in the distribution of reflection intensity acquired in step S211d (step S212e).

[0071] If it is determined that there is no lane pattern (step S212e: NO), the process returns to step S205. On the other hand, if it is determined that there is a lane pattern (step S212e: YES), the position estimation unit 13 compares the number of lanes in the reflection intensity map 31 with the number of detected lanes (step S215e). After completion of step S215e, the above-mentioned steps S220 to S230 are executed. In this embodiment, the correlation value in step S220 means the number of lanes itself. Also, in this embodiment, the positional deviation identified in step S225 and corrected in step S230 is mainly the positional deviation in the longitudinal direction D1 of the vehicle.

[0072] The vehicle position estimation device 100e of the sixth embodiment described above has the same effect as the vehicle position estimation device 100d of the fifth embodiment. The inventors of the present application have found that the reflection intensity is high at the lines (mainly white lines in Japan) that are the boundaries between lanes, and a pair of reflection intensity peaks with reflection intensities of a predetermined magnitude or more are generated in the distribution of reflection intensity, separated in the width direction D2 of the vehicle. Therefore, the vehicle position estimation device 100e of the sixth embodiment can accurately identify the number of lanes. In addition, the number of lanes is compared with the number of lanes in the reflection intensity map 31, and the position deviation of the vehicle along the length direction D1 of the vehicle is corrected using the comparison result, so that the position of the vehicle in the length direction D1 can be accurately estimated.

[0073] G. Seventh embodiment: A vehicle position estimation device 100f of the seventh embodiment shown in Fig. 23 differs from the vehicle position estimation device 100d of the fifth embodiment shown in Fig. 15 in that the CPU 10 functions as a curve identification unit 41 instead of the fence identification unit 18. Other configurations of the vehicle position estimation device 100f of the seventh embodiment are similar to those of the vehicle position estimation device 100d of the fifth embodiment, so the same components are denoted by the same reference numerals and detailed description thereof will be omitted.

[0074] The curve specifying unit 41 specifies a curve. A method for specifying a curve by the curve specifying unit 41 will be described with reference to FIG.

[0075] The curve identifying unit 41 identifies a curve from the reflection intensity distribution for each distance after correction. Fig. 24 shows an example of the reflection intensity distribution for each distance, similar to Fig. 21. In Fig. 24, the upper part shows the reflection intensity distribution at time T1, and the lower part shows the reflection intensity distribution at time T2, which is later than time T1. Note that peaks p11-p13, p21-p23, and p31-p33 similar to those in Fig. 21 appear in both the upper and lower parts of Fig. 24.

[0076] As shown in FIG. 24, when the reflection intensity distribution acquired at time T1 is compared with the reflection intensity distribution acquired at time T2, all of the peaks p11-p13, p21-p23, and p31-p33 are shifted to the right along the width direction D2. This indicates that the two lanes are curved to the right. If the two lanes are curved to the left, the peaks p11-p13, p21-p23, and p31-p33 will shift to the left along the width direction D1 over time. For this reason, the curve identification unit 41 identifies as a curve a portion where a pair of reflection intensity peaks that are located apart from each other in the width direction D2 of the vehicle and have a reflection intensity equal to or greater than a predetermined magnitude shift to the left or right over time.

[0077] In this embodiment, the reflection intensity map 31 stores a large number of points in association with the reflection intensity at each point, and also stores the position of the curve in advance.

[0078] The vehicle position estimation process in the seventh embodiment shown in Fig. 25 differs from the vehicle position estimation process in the fifth embodiment shown in Fig. 17 in that step S212f is executed instead of step S212d, and step S215f is executed instead of step S215d. Since the other steps of the vehicle position estimation process in the seventh embodiment are the same as those of the fifth embodiment, the same steps are denoted by the same reference numerals, and detailed descriptions thereof will be omitted.

[0079] After the distribution of reflection intensity for each distance is acquired in step S211d, the curve identification unit 41 determines whether or not there is a curve pattern in the distribution of reflection intensity acquired in step S211d (step S212f).

[0080] If it is determined that there is no curve pattern (step S212f: NO), the process returns to step S205. On the other hand, if it is determined that there is a curve pattern (step S212f: YES), the position estimation unit 13 compares the curve in the reflection intensity map 31 with the detected curve (step S215f). After completion of step S215f, the above-mentioned steps S220 to S230 are executed. In this embodiment, the position deviation identified in step S225 and corrected in step S230 is mainly the position deviation in the longitudinal direction D1 of the vehicle.

[0081] The vehicle position estimation device 100f of the seventh embodiment described above has the same effect as the vehicle position estimation device 100d of the fifth embodiment. The inventors of the present application have found that, in a curve, a pair of reflection intensity peaks that are located apart from each other in the width direction D2 of the vehicle and have a reflection intensity equal to or greater than a predetermined magnitude shift left or right over time. Therefore, the vehicle position estimation device 100f of the seventh embodiment can accurately identify the curve. In addition, the position of the curve is compared with the position of the curve in the reflection intensity map 31, and the position shift of the vehicle along the length direction D1 of the vehicle is corrected using the comparison result, so that the position of the vehicle in the length direction D1 can be accurately estimated.

[0082] H. Eighth embodiment: A vehicle position estimation device 100g of the eighth embodiment shown in Fig. 26 differs from the vehicle position estimation device 100d of the fifth embodiment shown in Fig. 15 in that the CPU 10 functions as a second slope section identification unit 42 instead of the fence identification unit 18. Since the other configurations of the vehicle position estimation device 100g of the eighth embodiment are similar to those of the vehicle position estimation device 100d of the fifth embodiment, the same components are denoted by the same reference numerals and detailed description thereof will be omitted.

[0083] The second slope identifying unit 42 identifies a slope. The second slope identifying unit 42 identifies a slope by a method different from that of the first slope identifying unit 15 of the third embodiment. The method of identifying a slope by the second slope identifying unit 42 will be described with reference to FIG.

[0084] The second slope identification unit 42 identifies a slope using the reflection intensity distribution for each distance after the correction. FIG. 27 shows an example of the reflection intensity distribution for each distance, similar to FIG. 21. In FIG. 27, the upper part shows the reflection intensity distribution at time T3, and the lower part shows the reflection intensity distribution at time T4 after time T3. Note that peaks p41-p42, p51-p52, and p61-p62 similar to those in FIG. 21 appear in both the upper and lower parts of FIG. 27. Note that the vehicle is traveling on a flat road at time T3, and is traveling at a position where there is a downhill slope ahead at time T4.

[0085] As shown in FIG. 27, when the reflection intensity distribution acquired at time T3 is compared with the reflection intensity distribution acquired at time T2, the length between three pairs of peaks, in other words, the length in the width direction D2, increases with time. This means that the vehicle is approaching a downhill slope. On a downhill slope, the distance in the width direction D2 between the white lines is perceived as larger (wider) than on a flat road even if the distance in the length direction D1 from the vehicle is the same. Therefore, the length between the identified reflection intensity peaks is detected as being large. On the other hand, on an uphill slope, the distance in the width direction D2 between the white lines is perceived as being smaller (narrower) than on a flat road even if the distance in the length direction D1 from the vehicle is the same. Therefore, the length between the identified reflection intensity peaks is detected as being small. For this reason, the second slope portion identification unit 42 identifies, as a slope portion, a portion in which the length between a pair of reflection intensity peaks located apart from each other in the width direction D2 and having a reflection intensity equal to or greater than a predetermined magnitude increases or decreases with time.

[0086] In this embodiment, the reflection intensity map 31 stores a large number of points in association with the reflection intensity at each point, and also stores the position of the slope portion in advance.

[0087] The vehicle position estimation process in the eighth embodiment shown in Fig. 28 differs from the vehicle position estimation process in the fifth embodiment shown in Fig. 17 in that step S212g is executed instead of step S212d, and step S215g is executed instead of step S215d. Since the other steps of the vehicle position estimation process in the eighth embodiment are the same as those of the fifth embodiment, the same steps are denoted by the same reference numerals and detailed descriptions thereof will be omitted.

[0088] After the distribution of reflection intensity for each distance is acquired in step S211d, the second slope identification unit 42 determines whether or not there is a slope pattern in the distribution of reflection intensity acquired in step S211d (step S212g).

[0089] If it is determined that there is no curve pattern (step S212g: NO), the process returns to step S205. On the other hand, if it is determined that there is a curve pattern (step S212g: YES), the position estimation unit 13 compares the slope portion of the reflection intensity map 31 with the detected slope portion (step S215g). After completion of step S215g, the above-mentioned steps S220 to S230 are executed. In this embodiment, the position deviation identified in step S225 and corrected in step S230 is mainly the position deviation in the longitudinal direction D1 of the vehicle.

[0090] The vehicle position estimation device 100g of the eighth embodiment described above has the same effect as the vehicle position estimation device 100d of the fifth embodiment. The inventors of the present application have found that in a slope, the length between a pair of reflection intensity peaks that are located apart from each other in the width direction D2 of the vehicle and have a reflection intensity equal to or greater than a predetermined magnitude widens or narrows over time. Specifically, the length between a pair of reflection intensity peaks narrows over time on a downhill slope, and widens over time on an uphill slope. Therefore, the vehicle position estimation device 100g of the eighth embodiment can accurately identify a slope. In addition, the slope is compared with the position of the slope in the reflection intensity map 31, and the position deviation of the vehicle along the length direction D1 of the vehicle is corrected using the comparison result, so that the position of the vehicle in the length direction D1 can be accurately estimated.

[0091] I. Ninth embodiment: A vehicle position estimation device 100h of the ninth embodiment shown in Fig. 29 differs from the vehicle position estimation device 100 of the first embodiment shown in Fig. 1 in that the CPU 10 also functions as a sign position identification unit 43. Other configurations of the vehicle position estimation device 100h of the ninth embodiment are similar to those of the vehicle position estimation device 100 of the first embodiment, so the same components are denoted by the same reference numerals and detailed descriptions thereof will be omitted.

[0092] The sign position identifying unit 43 identifies the position of a sign provided on the road surface. Such signs include any signs consisting of lines, symbols, letters, etc. directly drawn on the road, such as a sign indicating that there is a crosswalk ahead, a sign (line) indicating a crosswalk or a stop sign, a sign indicating a sharp curve, etc. In this embodiment, the reflection intensity map 31 stores a large number of points and the reflection intensity at each point in association with each other, and also stores the positions of the above-mentioned signs in advance.

[0093] The vehicle position estimation process in the ninth embodiment shown in Fig. 30 differs from the vehicle position estimation process in the first embodiment shown in Fig. 4 in that steps S211h and S212h are additionally executed, and step S215h is executed instead of step S215. Since the other steps of the vehicle position estimation process in the ninth embodiment are the same as those in the first embodiment, the same steps are denoted by the same reference numerals, and detailed descriptions thereof will be omitted.

[0094] After completion of step S210, the sign position identifying unit 43 searches for signs on the road from the reflection intensities acquired in step S205 including the corrected reflection intensities (step S211h). For example, the sign position identifying unit 43 identifies as a sign a portion where detection points having a reflection intensity greater than a predetermined size compared to other road detection points are gathered in a predetermined size and shape.

[0095] The position estimation unit 13 determines whether or not a sign has been detected (step S212h), and if it is determined that the sign has not been detected (step S212h: NO), the process returns to step S205. On the other hand, if it is determined that the sign has been detected (step S212h: YES), the position estimation unit 13 compares the sign in the reflection intensity map 31 with the detected sign (step S215h). After completion of step S215h, the above-mentioned steps S220 to S230 are executed. In this embodiment, the position deviation identified in step S225 and corrected in step S230 is mainly the position deviation in the longitudinal direction D1 of the vehicle. This will be described with reference to FIG. 31.

[0096] In Fig. 31, a vehicle VL1 equipped with a vehicle position estimation device 100h is traveling in a first lane L1. A sign S10 indicated by a dashed line in Fig. 31 indicates a sign recognized by the on-board sensor 200. On the other hand, a sign S11 indicated by a solid line indicates a sign stored in the reflection intensity map 31.

[0097] 31, a positional deviation Δd3 in the longitudinal direction D1 is identified by comparing the sign S10 with the sign S11. Then, the current position of the vehicle is corrected and estimated so as to cancel the positional deviation Δd3.

[0098] The vehicle position estimation device 100h of the ninth embodiment described above has the same effects as the vehicle position estimation device 100 of the first embodiment. In addition, the position of a sign identified using the reflection intensities of a plurality of detection points is compared with the position of a sign identified from the reflection intensity map 31, and the positional deviation of the vehicle VL1 along the length direction D1 of the vehicle VL1 is corrected using the comparison result, so that the positional deviation of the vehicle VL1 along the length direction D1 can be corrected with high accuracy.

[0099] J. Other Embodiments: (J1) In each embodiment, the reflection intensity map 31 is provided in the vehicle position estimation device 100, 100a to 100h, but the present disclosure is not limited to this. For example, the reflection intensity map 31 may be provided in another device such as an ECU mounted on the vehicle. Also, the reflection intensity map 31 may be provided in an external device of the vehicle. In such a configuration, for example, a server device capable of communicating with the vehicle may be provided with the reflection intensity map 31. The vehicle may then be provided with a wireless communication device for wirelessly communicating with the server device, and may refer to the reflection intensity map 31 through such wireless communication.

[0100] (J2) In each embodiment, the reflection intensity at the road detection point is corrected by the above formula (1), but the reflection intensity at the road detection point may be corrected by any calculation formula that can correct the reflection intensity so that the difference in reflection intensity caused by the difference in distance is reduced. Also, instead of calculating by a calculation formula, a correction table in which the reflection intensity after correction is set in advance for the reflection intensity before correction may be set by experiment, simulation, or the like, and the reflection intensity at the road detection point may be corrected by referring to such a table.

[0101] (J3) In each embodiment, the correction table generation process is executed when the user performs a predetermined operation on the vehicle, but the present disclosure is not limited to this. For example, the correction table generation process may be executed automatically when the ignition is turned on. Also, for example, the current position of the vehicle identified by the navigation system may be automatically executed when the vehicle stops on a flat road at a predetermined location, such as the user's home parking lot. In such a configuration, the user's convenience can be improved, and the correction table 32 is generated using the reflection intensity obtained on a flat road, so that a more accurate table can be generated as the correction table 32 on a flat road on which the vehicle is generally driven.

[0102] (J4) In each embodiment, before comparing a structure recorded in the reflection intensity map 31 with a structure recognized by the on-board sensor 200, the likelihood that the structure recognized by the on-board sensor 200 is indeed the target structure may be identified, and a comparison may be performed if the likelihood is high. For example, in a configuration in which the vehicle is equipped with an imaging device, the shape and size of a structure (characteristic portion, slope, fence, recess or protrusion, lane, curve, sign) captured in an image obtained by the imaging device may be compared (by performing pattern matching) with the shape and size of the structure in a sample image of the structure to be compared in advance to obtain a similarity, and a comparison using the reflection intensity map 31 may be performed if the similarity is equal to or greater than a predetermined size.

[0103] (J5) The vehicle location identification device 100, 100a to 100h and the method thereof described in the present disclosure may be realized by a dedicated computer provided by configuring a processor and a memory programmed to execute one or more functions embodied in a computer program. Alternatively, the vehicle location identification device 100, 100a to 100h and the method thereof described in the present disclosure may be realized by a dedicated computer provided by configuring a processor with one or more dedicated hardware logic circuits. Alternatively, the vehicle location identification device 100, 100a to 100h and the method thereof described in the present disclosure may be realized by one or more dedicated computers configured by a combination of a processor and a memory programmed to execute one or more functions and a processor configured with one or more hardware logic circuits. In addition, the computer program may be stored in a computer-readable non-transitory tangible recording medium as instructions executed by a computer.

[0104] The present disclosure is not limited to the above-mentioned embodiments, and can be realized in various configurations without departing from the spirit of the present disclosure. For example, the technical features in each embodiment corresponding to the technical features in the form described in the Summary of the Invention column can be appropriately replaced or combined in order to solve some or all of the above-mentioned problems or to achieve some or all of the above-mentioned effects. Furthermore, if a technical feature is not described as essential in this specification, it can be appropriately deleted. [Explanation of symbols]

[0105] 12...reflection intensity acquisition unit, 13...correction unit, 14...position estimation unit, 31...reflection intensity map, 100, 100a-100h...vehicle position estimation device, 200...vehicle-mounted sensor, VL1...vehicle

Claims

1. A vehicle position estimation device (100, 100a-100h) mounted on a vehicle (VL1) for estimating a position of the vehicle, a reflection intensity acquisition unit (11) that acquires the detected reflection intensity from an on-vehicle sensor (200) that irradiates an electromagnetic wave, identifies a plurality of detection points by receiving a reflected wave of the electromagnetic wave, and detects a reflection intensity, which is a reception intensity of the reflected wave at each of the plurality of detection points; a correction unit (12) that corrects the reflection intensity at a road detection point that is a detection point corresponding to a road among the plurality of detection points so as to reduce a difference in the reflection intensity caused by a difference in distance from the vehicle; a position estimation unit (14) that estimates a position of the vehicle by comparing a reflection intensity map (31) that stores at least a plurality of points and the reflection intensities at the plurality of points in association with each other in advance with the reflection intensities at the plurality of detection points, including the reflection intensities corrected by the correction unit; Equipped with a first slope identification unit (15) that identifies, among the road detection points, a set of the road detection points in which the reflection intensity after correction by the correction unit differs from the reflection intensity after correction by the correction unit at other road detection points by a predetermined magnitude or more as a slope portion (SL1); The reflection intensity map stores the position of the slope portion in advance, A vehicle position estimation device, wherein the position estimation unit compares the position of the slope identified by the first slope identification unit with the position of the slope in the reflection intensity map, and uses the result of the comparison to correct the position shift of the vehicle along the longitudinal direction of the vehicle.

2. A vehicle position estimation device (100, 100a-100h) mounted on a vehicle (VL1) for estimating a position of the vehicle, a reflection intensity acquisition unit (11) that acquires the detected reflection intensity from an on-vehicle sensor (200) that irradiates an electromagnetic wave, identifies a plurality of detection points by receiving a reflected wave of the electromagnetic wave, and detects a reflection intensity, which is a reception intensity of the reflected wave at each of the plurality of detection points; a correction unit (12) that corrects the reflection intensity at a road detection point that is a detection point corresponding to a road among the plurality of detection points so as to reduce a difference in the reflection intensity caused by a difference in distance from the vehicle; a position estimation unit (14) that estimates a position of the vehicle by comparing a reflection intensity map (31) that stores at least a plurality of points and the reflection intensities at the plurality of points in association with each other in advance with the reflection intensities at the plurality of detection points, including the reflection intensities corrected by the correction unit; Equipped with a convexity / concave identification unit (16) that identifies, among the road detection points, a set of road detection points in which the reflection intensity after correction by the correction unit differs by a predetermined magnitude or more from the reflection intensity after correction by the correction unit at other road detection points, and the set has a size in a plan view that is equal to or smaller than a predetermined magnitude, as a concave or convex portion (PR0); The reflection intensity map stores in advance the positions of the concave and convex portions, A vehicle position estimation device, wherein the position estimation unit compares the position of the concave or convex portion identified by the unevenness identification unit with the position of the concave or convex portion in the reflection intensity map, and uses the result of the comparison to correct the positional deviation of the vehicle along the longitudinal direction of the vehicle.

3. A vehicle position estimation device (100, 100a-100h) mounted on a vehicle (VL1) for estimating a position of the vehicle, a reflection intensity acquisition unit (11) that acquires the detected reflection intensity from an on-vehicle sensor (200) that irradiates an electromagnetic wave, identifies a plurality of detection points by receiving a reflected wave of the electromagnetic wave, and detects a reflection intensity, which is a reception intensity of the reflected wave at each of the plurality of detection points; a correction unit (12) that corrects the reflection intensity at a road detection point that is a detection point corresponding to a road among the plurality of detection points so as to reduce a difference in the reflection intensity caused by a difference in distance from the vehicle; a position estimation unit (14) that estimates a position of the vehicle by comparing a reflection intensity map (31) that stores at least a plurality of points and the reflection intensities at the plurality of points in association with each other in advance with the reflection intensities at the plurality of detection points, including the reflection intensities corrected by the correction unit; Equipped with A reflection intensity distribution acquisition unit (17) that acquires a distribution of the reflection intensity for each distance from the vehicle; a fence identification unit (18) that identifies, among the acquired distributions, a set of detection points in which the reflection intensity differs by a predetermined magnitude or more in the distribution beyond a certain distance from the distribution before the certain distance within a range of a predetermined length or less in a direction parallel to a width direction of the vehicle, as a fence (Fe1); Furthermore, The reflection intensity map stores the position of the fence in advance, A vehicle position estimation device, wherein the position estimation unit compares the position of the fence identified by the fence identification unit with the position of the fence in the reflection intensity map, and uses the result of the comparison to correct a position shift of the vehicle along the longitudinal direction of the vehicle.

4. A vehicle position estimation device (100, 100a-100h) mounted on a vehicle (VL1) for estimating a position of the vehicle, a reflection intensity acquisition unit (11) that acquires the detected reflection intensity from an on-vehicle sensor (200) that irradiates an electromagnetic wave, identifies a plurality of detection points by receiving a reflected wave of the electromagnetic wave, and detects a reflection intensity, which is a reception intensity of the reflected wave at each of the plurality of detection points; a correction unit (12) that corrects the reflection intensity at a road detection point that is a detection point corresponding to a road among the plurality of detection points so as to reduce a difference in the reflection intensity caused by a difference in distance from the vehicle; a position estimation unit (14) that estimates a position of the vehicle by comparing a reflection intensity map (31) that stores at least a plurality of points and the reflection intensities at the plurality of points in association with each other in advance with the reflection intensities at the plurality of detection points, including the reflection intensities corrected by the correction unit; Equipped with a reflection intensity distribution acquisition unit that acquires a distribution of the reflection intensity for each distance from the vehicle; a lane number determination unit (19) that determines, in the acquired distribution, the number of pairs of reflection intensity peaks (p11-p13, p21-p23, p31-p33) that are spaced apart from each other in the width direction of the vehicle and have a reflection intensity equal to or greater than a predetermined magnitude, as the number of lanes; Furthermore, The reflection intensity map stores lanes in advance, A vehicle position estimation device, wherein the position estimation unit compares the number of lanes identified by the lane number identification unit with the number of lanes in the reflection intensity map, and uses the result of the comparison to correct a position shift of the vehicle along the longitudinal direction of the vehicle.

5. A vehicle position estimation device (100, 100a-100h) mounted on a vehicle (VL1) for estimating a position of the vehicle, a reflection intensity acquisition unit (11) that acquires the detected reflection intensity from an on-vehicle sensor (200) that irradiates an electromagnetic wave, identifies a plurality of detection points by receiving a reflected wave of the electromagnetic wave, and detects a reflection intensity, which is a reception intensity of the reflected wave at each of the plurality of detection points; a correction unit (12) that corrects the reflection intensity at a road detection point that is a detection point corresponding to a road among the plurality of detection points so as to reduce a difference in the reflection intensity caused by a difference in distance from the vehicle; a position estimation unit (14) that estimates a position of the vehicle by comparing a reflection intensity map (31) that stores at least a plurality of points and the reflection intensities at the plurality of points in association with each other in advance with the reflection intensities at the plurality of detection points, including the reflection intensities corrected by the correction unit; Equipped with A reflection intensity distribution acquisition unit (17) that acquires a distribution of the reflection intensity for each distance from the vehicle; a curve identification unit (41) that identifies, in the acquired distribution, a portion where a pair of reflection intensity peaks (p11-p13, p21-p23, p31-p33) that are located apart from each other in the width direction of the vehicle and have a reflection intensity equal to or greater than a predetermined magnitude shifts to the left or right over time as a curve; Further equipped with The reflection intensity map stores the position of the curve in advance, A vehicle position estimation device, wherein the position estimation unit compares the position of the curve identified by the curve identification unit with the position of the curve in the reflection intensity map, and uses the result of the comparison to correct a position shift of the vehicle along the longitudinal direction of the vehicle.

6. A vehicle position estimation device (100, 100a-100h) mounted on a vehicle (VL1) for estimating a position of the vehicle, a reflection intensity acquisition unit (11) that acquires the detected reflection intensity from an on-vehicle sensor (200) that irradiates an electromagnetic wave, identifies a plurality of detection points by receiving a reflected wave of the electromagnetic wave, and detects a reflection intensity, which is a reception intensity of the reflected wave at each of the plurality of detection points; a correction unit (12) that corrects the reflection intensity at a road detection point that is a detection point corresponding to a road among the plurality of detection points so as to reduce a difference in the reflection intensity caused by a difference in distance from the vehicle; a position estimation unit (14) that estimates a position of the vehicle by comparing a reflection intensity map (31) that stores at least a plurality of points and the reflection intensities at the plurality of points in association with each other in advance with the reflection intensities at the plurality of detection points, including the reflection intensities corrected by the correction unit; Equipped with A reflection intensity distribution acquisition unit (17) that acquires a distribution of the reflection intensity for each distance from the vehicle; a second slope identifying unit (42) that identifies, in the acquired distribution, a portion where a length between a pair of reflection intensity peaks (p41-p42, p51-p52, p61-p62) that are located apart from each other in the width direction of the vehicle and have a reflection intensity equal to or greater than a predetermined magnitude increases or decreases over time as a slope; Further equipped with The reflection intensity map stores the position of the slope portion in advance, A vehicle position estimation device, wherein the position estimation unit compares the position of the slope identified by the second slope identification unit with the position of the slope in the reflection intensity map, and uses the result of the comparison to correct the position shift of the vehicle along the longitudinal direction of the vehicle.

7. 7. The vehicle position estimation device according to claim 1, The correction unit is correcting the reflection intensity at the road detection point by referring to a correction table (32) consisting of a plurality of pairs of the distance from the vehicle and the reflection intensity; When a reflection intensity I of the road detection point at a distance R from the vehicle is detected by the vehicle-mounted sensor, a corrected reflection intensity I is calculated using equation (1); Icalib=(Iref / α)×I...(1) In the formula (1), Iref represents a predetermined reference reflection intensity Iref that serves as a reference for the reflection intensity on the road, and α represents a correction coefficient α calculated by the formula (2), α=[(i1-i0) / (r1-r0)]×(R-r0)+i0...(2) In the formula (2), r0 and r1 represent different distances from the vehicle, i0 and i1 represent the reflection intensities, r0 and i0, and r1 and i1 are both pairs included in the plurality of pairs, A vehicle position estimation device, wherein the magnitude of the distance R is between the distance r0 and the distance r1.

8. The vehicle position estimation device according to any one of claims 1 to 7, A sign position identification unit (43) is further provided for identifying a position of a sign (S10) provided on a road surface by using the reflection intensities at the plurality of detection points, The reflection intensity map stores the positions of the markers in advance, a position estimating unit that compares the position of the sign identified by the sign position identifying unit with the position of the sign in the reflection intensity map, and corrects a position deviation of the vehicle along the longitudinal direction of the vehicle using a result of the comparison.

9. A vehicle position estimation method for estimating a position of a vehicle (VL1), comprising: A step (S205) of identifying a plurality of detection points by irradiating electromagnetic waves and receiving reflected waves of the electromagnetic waves, and acquiring the detected reflection intensities from an on-vehicle sensor (200) that detects a reflection intensity, which is a reception intensity of the reflected waves at each of the plurality of detection points; a step (S210) of correcting the reflection intensities at road detection points, which are detection points corresponding to roads among the plurality of detection points, so as to reduce a difference in the reflection intensities caused by a difference in distance from the vehicle; a step (S230) of estimating a position of the vehicle by comparing the reflection intensities of the plurality of detection points, including the reflection intensities corrected by the correcting step, with a reflection intensity map (31) in which at least a plurality of points and the reflection intensities at the plurality of points are previously associated and stored; Equipped with a first slope portion identification step of identifying, among the road detection points, a set of the road detection points whose reflection intensity after correction in the correcting step differs by a predetermined magnitude or more from the reflection intensity after correction in the correcting step at other road detection points as a slope portion (SL1); A vehicle position estimation method, wherein the step of estimating the position of the vehicle includes a step of comparing the position of the slope identified by the first slope identification step with the position of the slope in the reflection intensity map, and correcting a positional deviation of the vehicle along the longitudinal direction of the vehicle using a result of the comparison.

10. A vehicle position estimation method for estimating a position of a vehicle (VL1), comprising: A step (S205) of identifying a plurality of detection points by irradiating electromagnetic waves and receiving reflected waves of the electromagnetic waves, and acquiring the detected reflection intensities from an on-vehicle sensor (200) that detects a reflection intensity, which is a reception intensity of the reflected waves at each of the plurality of detection points; a step (S210) of correcting the reflection intensities at road detection points, which are detection points corresponding to roads among the plurality of detection points, so as to reduce a difference in the reflection intensities caused by a difference in distance from the vehicle; a step (S230) of estimating a position of the vehicle by comparing the reflection intensities of the plurality of detection points, including the reflection intensities corrected by the correcting step, with a reflection intensity map (31) in which at least a plurality of points and the reflection intensities at the plurality of points are previously associated and stored; Equipped with a convexity / concave identification step of identifying a group of the road detection points, the group being a concave or convex portion (PR0), the group being a group of the road detection points in which the reflection intensity after correction by the correcting step differs by a predetermined magnitude or more from the reflection intensity after correction by the correcting step at other road detection points, the group being a group having a size in a plan view that is equal to or smaller than a predetermined magnitude, The reflection intensity map stores in advance the positions of the concave and convex portions, A vehicle position estimation method, wherein the step of estimating the position of the vehicle includes a step of comparing the position of the concave or convex portion identified by the unevenness identification step with the position of the concave or convex portion in the reflection intensity map, and correcting a positional deviation of the vehicle along the longitudinal direction of the vehicle using a result of the comparison.

11. A vehicle position estimation method for estimating a position of a vehicle (VL1), comprising: A step (S205) of identifying a plurality of detection points by irradiating electromagnetic waves and receiving reflected waves of the electromagnetic waves, and acquiring the detected reflection intensities from an on-vehicle sensor (200) that detects a reflection intensity, which is a reception intensity of the reflected waves at each of the plurality of detection points; a step (S210) of correcting the reflection intensities at road detection points, which are detection points corresponding to roads among the plurality of detection points, so as to reduce a difference in the reflection intensities caused by a difference in distance from the vehicle; a step (S230) of estimating a position of the vehicle by comparing the reflection intensities of the plurality of detection points, including the reflection intensities corrected by the correcting step, with a reflection intensity map (31) in which at least a plurality of points and the reflection intensities at the plurality of points are previously associated and stored; Equipped with acquiring a distribution of the reflection intensity for each distance from the vehicle; a fence identification process for identifying, as a fence (Fe1), a set of detection points in the distribution beyond a certain distance from the acquired distribution, where the reflection intensity differs by a predetermined magnitude or more in a range of a predetermined length or less in a direction parallel to a width direction of the vehicle, compared to the distribution before the certain distance; Furthermore, The reflection intensity map stores the position of the fence in advance, A vehicle position estimation method, wherein the step of estimating the position of the vehicle includes a step of comparing the position of the fence identified in the fence identification step with the position of the fence in the reflection intensity map, and correcting a positional deviation of the vehicle along the longitudinal direction of the vehicle using a result of the comparison.

12. A vehicle position estimation method for estimating a position of a vehicle (VL1), comprising: A step (S205) of identifying a plurality of detection points by irradiating electromagnetic waves and receiving reflected waves of the electromagnetic waves, and acquiring the detected reflection intensities from an on-vehicle sensor (200) that detects a reflection intensity, which is a reception intensity of the reflected waves at each of the plurality of detection points; a step (S210) of correcting the reflection intensities at road detection points, which are detection points corresponding to roads among the plurality of detection points, so as to reduce a difference in the reflection intensities caused by a difference in distance from the vehicle; a step (S230) of estimating a position of the vehicle by comparing the reflection intensities of the plurality of detection points, including the reflection intensities corrected by the correcting step, with a reflection intensity map (31) in which at least a plurality of points and the reflection intensities at the plurality of points are previously associated and stored; Equipped with acquiring a distribution of the reflection intensity for each distance from the vehicle; a lane number determination process for determining, in the acquired distribution, the number of pairs of reflection intensity peaks (p11-p13, p21-p23, p31-p33) that are spaced apart from each other in the width direction of the vehicle and have a reflection intensity equal to or greater than a predetermined magnitude, as the number of lanes; Furthermore, The reflection intensity map stores lanes in advance, A vehicle position estimation method, wherein the step of estimating the position of the vehicle includes a step of comparing the number of lanes identified by the lane number identification step with the number of lanes in the reflection intensity map, and correcting a position shift of the vehicle along the longitudinal direction of the vehicle using a result of the comparison.

13. A vehicle position estimation method for estimating a position of a vehicle (VL1), comprising: A step (S205) of identifying a plurality of detection points by irradiating electromagnetic waves and receiving reflected waves of the electromagnetic waves, and acquiring the detected reflection intensities from an on-vehicle sensor (200) that detects a reflection intensity, which is a reception intensity of the reflected waves at each of the plurality of detection points; a step (S210) of correcting the reflection intensities at road detection points, which are detection points corresponding to roads among the plurality of detection points, so as to reduce a difference in the reflection intensities caused by a difference in distance from the vehicle; a step (S230) of estimating a position of the vehicle by comparing the reflection intensities of the plurality of detection points, including the reflection intensities corrected by the correcting step, with a reflection intensity map (31) in which at least a plurality of points and the reflection intensities at the plurality of points are previously associated and stored; Equipped with acquiring a distribution of the reflection intensity for each distance from the vehicle; a curve identification process for identifying a portion in the distribution obtained where a pair of reflection intensity peaks (p11-p13, p21-p23, p31-p33) that are spaced apart from each other in the width direction of the vehicle and have a reflection intensity equal to or greater than a predetermined magnitude shifts to the left or right over time as a curve; Further equipped with The reflection intensity map stores the position of the curve in advance, A vehicle position estimation method, wherein the step of estimating the position of the vehicle includes a step of comparing the position of the curve identified by the curve identification step with the position of the curve in the reflection intensity map, and correcting a positional deviation of the vehicle along the longitudinal direction of the vehicle using a result of the comparison.

14. A vehicle position estimation method for estimating a position of a vehicle (VL1), comprising: A step (S205) of identifying a plurality of detection points by irradiating electromagnetic waves and receiving reflected waves of the electromagnetic waves, and acquiring the detected reflection intensities from an on-vehicle sensor (200) that detects a reflection intensity, which is a reception intensity of the reflected waves at each of the plurality of detection points; a step (S210) of correcting the reflection intensities at road detection points, which are detection points corresponding to roads among the plurality of detection points, so as to reduce a difference in the reflection intensities caused by a difference in distance from the vehicle; a step (S230) of estimating a position of the vehicle by comparing the reflection intensities of the plurality of detection points, including the reflection intensities corrected by the correcting step, with a reflection intensity map (31) in which at least a plurality of points and the reflection intensities at the plurality of points are previously associated and stored; Equipped with acquiring a distribution of the reflection intensity for each distance from the vehicle; a second slope portion identification process for identifying, in the acquired distribution, a portion where a length between a pair of reflection intensity peaks (p41-p42, p51-p52, p61-p62) that are located apart from each other in the width direction of the vehicle and have a reflection intensity equal to or greater than a predetermined magnitude increases or decreases over time, as a slope portion; Further equipped with The reflection intensity map stores the position of the slope portion in advance, A vehicle position estimation method, wherein the step of estimating the position of the vehicle includes a step of comparing the position of the slope identified by the second slope identification step with the position of the slope in the reflection intensity map, and correcting a positional deviation of the vehicle along the longitudinal direction of the vehicle using a result of the comparison.

15. A computer program for estimating a position of a vehicle (VL1), comprising: a function of irradiating electromagnetic waves, identifying a plurality of detection points by receiving reflected waves of the electromagnetic waves, and acquiring the detected reflection intensities from an on-board sensor (200) that detects a reflection intensity, which is the reception intensity of the reflected waves at each of the plurality of detection points; a function of correcting the reflection intensity at road detection points, which are detection points corresponding to roads among the plurality of detection points, so as to reduce a difference in the reflection intensity caused by a difference in distance from the vehicle; a function of estimating a position of the vehicle by comparing a reflection intensity map (31) in which at least a plurality of points and the reflection intensities at the plurality of points are previously associated and stored with each other, with the reflection intensities at the plurality of detection points including the reflection intensities corrected by the correction function; This is realized on a computer. a first slope identification function that identifies, among the road detection points, a set of the road detection points in which the reflection intensity after correction by the correction function differs by a predetermined magnitude or more from the reflection intensity after correction by the correction function at other road detection points as a slope portion (SL1); The reflection intensity map stores the position of the slope portion in advance, A computer program, wherein the function of estimating the position of the vehicle includes a function of comparing the position of the slope identified by the first slope identification function with the position of the slope in the reflection intensity map, and using the result of the comparison to correct a positional deviation of the vehicle along the longitudinal direction of the vehicle.

16. A computer program for estimating a position of a vehicle (VL1), comprising: a function of irradiating electromagnetic waves, identifying a plurality of detection points by receiving reflected waves of the electromagnetic waves, and acquiring the detected reflection intensities from an on-board sensor (200) that detects a reflection intensity, which is the reception intensity of the reflected waves at each of the plurality of detection points; a function of correcting the reflection intensity at road detection points, which are detection points corresponding to roads among the plurality of detection points, so as to reduce a difference in the reflection intensity caused by a difference in distance from the vehicle; a function of estimating a position of the vehicle by comparing a reflection intensity map (31) in which at least a plurality of points and the reflection intensities at the plurality of points are previously associated and stored with each other, with the reflection intensities at the plurality of detection points including the reflection intensities corrected by the correction function; This is realized on a computer. further realizing in the computer an unevenness identifying function for identifying a set of the road detection points, among the road detection points, in which the reflection intensity after correction by the correcting function differs by a predetermined size or more from the reflection intensity after correction by the correcting function at other road detection points, and in which the set has a size in a plan view that is equal to or smaller than a predetermined size, as a concave or convex portion (PR0); The reflection intensity map stores in advance the positions of the concave and convex portions, A computer program, wherein the function of estimating the position of the vehicle includes a function of comparing the position of the concave or convex portion identified by the unevenness identification function with the position of the concave or convex portion in the reflection intensity map, and using the result of the comparison to correct the positional deviation of the vehicle along the longitudinal direction of the vehicle.

17. A computer program for estimating a position of a vehicle (VL1), comprising: a function of irradiating electromagnetic waves, identifying a plurality of detection points by receiving reflected waves of the electromagnetic waves, and acquiring the detected reflection intensities from an on-board sensor (200) that detects a reflection intensity, which is the reception intensity of the reflected waves at each of the plurality of detection points; a function of correcting the reflection intensity at road detection points, which are detection points corresponding to roads among the plurality of detection points, so as to reduce a difference in the reflection intensity caused by a difference in distance from the vehicle; a function of estimating a position of the vehicle by comparing a reflection intensity map (31) in which at least a plurality of points and the reflection intensities at the plurality of points are previously stored in correspondence with each other, with the reflection intensities at the plurality of detection points including the reflection intensities corrected by the correction function; This is realized on a computer. A function of acquiring a distribution of the reflection intensity for each distance from the vehicle; a fence identification function that identifies, among the acquired distributions, a set of detection points in the distribution beyond a certain distance, in which the reflection intensity differs by a predetermined magnitude or more in a range of a predetermined length or less in a direction parallel to a width direction of the vehicle, as a fence (Fe1), compared to the distribution before the certain distance; The computer further executes the following: The reflection intensity map stores the position of the fence in advance, A computer program, wherein the function of estimating the vehicle's position includes a function of comparing the position of the fence identified by the fence identification function with the position of the fence in the reflection intensity map, and using the result of the comparison to correct a positional deviation of the vehicle along the longitudinal direction of the vehicle.

18. A computer program for estimating a position of a vehicle (VL1), comprising: a function of irradiating electromagnetic waves, identifying a plurality of detection points by receiving reflected waves of the electromagnetic waves, and acquiring the detected reflection intensity from an on-board sensor (200) that detects a reflection intensity, which is the reception intensity of the reflected waves at each of the plurality of detection points; a function of correcting the reflection intensity at road detection points, which are detection points corresponding to roads among the plurality of detection points, so as to reduce a difference in the reflection intensity caused by a difference in distance from the vehicle; a function of estimating a position of the vehicle by comparing a reflection intensity map (31) in which at least a plurality of points and the reflection intensities at the plurality of points are previously stored in correspondence with each other, with the reflection intensities at the plurality of detection points including the reflection intensities corrected by the correction function; This is realized on a computer. A function of acquiring a distribution of the reflection intensity for each distance from the vehicle; a lane number identification function for identifying, in the acquired distribution, the number of pairs of reflection intensity peaks (p11-p13, p21-p23, p31-p33) that are spaced apart from each other in the width direction of the vehicle and have a reflection intensity equal to or greater than a predetermined magnitude, as the number of lanes; The computer further executes the following: The reflection intensity map stores lanes in advance, The function of estimating the position of the vehicle includes a function of comparing the number of lanes identified by the lane number identification function with the number of lanes in the reflection intensity map, and using the result of the comparison to estimate the positional deviation of the vehicle along the length of the vehicle.

19. A computer program for estimating a position of a vehicle (VL1), comprising: a function of irradiating electromagnetic waves, identifying a plurality of detection points by receiving reflected waves of the electromagnetic waves, and acquiring the detected reflection intensity from an on-board sensor (200) that detects a reflection intensity, which is the reception intensity of the reflected waves at each of the plurality of detection points; a function of correcting the reflection intensity at road detection points, which are detection points corresponding to roads among the plurality of detection points, so as to reduce a difference in the reflection intensity caused by a difference in distance from the vehicle; a function of estimating a position of the vehicle by comparing a reflection intensity map (31) in which at least a plurality of points and the reflection intensities at the plurality of points are previously stored in correspondence with each other, with the reflection intensities at the plurality of detection points including the reflection intensities corrected by the correction function; This is realized on a computer. A function of acquiring a distribution of the reflection intensity for each distance from the vehicle; a curve identification function that identifies a portion in the distribution acquired where a pair of reflection intensity peaks (p11-p13, p21-p23, p31-p33) that are spaced apart from each other in the width direction of the vehicle and have a reflection intensity equal to or greater than a predetermined magnitude shifts to the left or right over time as a curve; The computer further executes the following: The reflection intensity map stores the position of the curve in advance, A computer program, wherein the function of estimating the position of the vehicle includes a function of comparing the position of the curve identified by the curve identification function with the position of the curve in the reflection intensity map, and using the result of the comparison to correct a positional deviation of the vehicle along the length of the vehicle.

20. A computer program for estimating a position of a vehicle (VL1), comprising: a function of irradiating electromagnetic waves, identifying a plurality of detection points by receiving reflected waves of the electromagnetic waves, and acquiring the detected reflection intensities from an on-board sensor (200) that detects a reflection intensity, which is the reception intensity of the reflected waves at each of the plurality of detection points; a function of correcting the reflection intensity at road detection points, which are detection points corresponding to roads among the plurality of detection points, so as to reduce a difference in the reflection intensity caused by a difference in distance from the vehicle; a function of estimating a position of the vehicle by comparing a reflection intensity map (31) in which at least a plurality of points and the reflection intensities at the plurality of points are previously associated and stored with each other, with the reflection intensities at the plurality of detection points including the reflection intensities corrected by the correction function; This is realized on a computer. A function of acquiring a distribution of the reflection intensity for each distance from the vehicle; a second slope identification function that identifies, in the acquired distribution, a portion where a length between a pair of reflection intensity peaks (p41-p42, p51-p52, p61-p62) that are located apart from each other in the width direction of the vehicle and have a reflection intensity equal to or greater than a predetermined magnitude increases or decreases over time as a slope portion; The computer further implements the following: The reflection intensity map stores the position of the slope portion in advance, A computer program, wherein the function of estimating the position of the vehicle includes a function of comparing the position of the slope identified by the second slope identification function with the position of the slope in the reflection intensity map, and using the result of the comparison to correct the positional deviation of the vehicle along the longitudinal direction of the vehicle.

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