RU2777308C1 - Method for estimating one's own location and apparatus for estimating one's own location - Google Patents

Abstract

FIELD: computing technology.

SUBSTANCE: invention relates to a method for estimating one's own location and an apparatus for estimating one's own location. Method for estimating one's own location includes detecting a road sign near the vehicle, determining the current location of the vehicle, obtaining information on the altitude of the detected road sign from the map data wherein information on the two-dimensional coordinates and the altitude of the road sign located near the road is recorded, based on the relative location of the detected road sign relative to the vehicle and the current location, and estimating the altitude of the vehicle according to the height information obtained from the map data.

EFFECT: possibility of determining on which of the roads located at different altitudes the vehicle is located.

7 cl, 6 dwg

Description

Technical field

[0001] The present invention relates to a method for estimating own position and a device for estimating own position.

State of the art

[0002] Patent Document 1 discloses a technology for determining whether the current location of a vehicle is on a normal road or on an expressway based on whether there is a normal road identification image in the image of the area in the vicinity of the vehicle captured by the camera. to identify that the vehicle is traveling on a normal road, or an expressway identification image to identify that the vehicle is traveling on an expressway.

patent document

[0003] Patent Document 1: JP 2006-317286A.

Technical problem

[0004] Although the technology described in Patent Document 1 is able to distinguish between roads whose types are different from each other, the technology is not able to distinguish between different roads whose types are the same.

Thus, when different roads whose types are the same respectively exist at different heights and the 2D road locations are close to each other, it sometimes becomes impossible to determine which road a vehicle is on.

The object of the present invention is to provide the possibility of determining on which one of the roads located at different heights the vehicle is located.

Solution

[0005] According to one aspect of the present invention, a method for estimating own location is provided, including: detecting a traffic sign in the vicinity of a vehicle; determining the current location of the vehicle; obtaining information about the height of the detected traffic sign from the map data, in which information about the two-dimensional coordinates and information about the height of the traffic sign located near the road is recorded, based on the relative position of the detected traffic sign with respect to the vehicle and the current location; and estimating the height at which the vehicle is located according to the height information obtained from the map data.

Advantageous Effects of the Invention

[0006] According to an aspect of the present invention, it is possible to determine on which of the roads located at different heights the vehicle is located.

The object and advantages of the invention will be realized and solved by means of the elements and combinations specified in the claims. It is to be understood that both the foregoing general description and the following detailed description are illustrative and explanatory and do not limit the invention.

Brief description of the drawings

[0007] FIG. 1 is a schematic configuration diagram of an example of a driving assistance device according to the embodiment;

Fig. 2 is an explanatory diagram of an example of the own position estimation method according to the embodiment;

Fig. 3 is a block diagram illustrating an example of the functional configuration of the electronic control unit (ECU) shown in FIG. one;

Fig. 4 is an explanatory diagram of an example of a method for calculating two-dimensional coordinates of a road sign;

Fig. 5 is a flowchart of an example of a driving assistance method according to the embodiment; and

Fig. 6 is a flowchart of an example of the own location estimation method shown in FIG. 5.

Description of embodiments of the invention

[0008] An embodiment of the present invention will now be described with reference to the drawings.

Configuration

Reference will now be made to FIG. 1. The driving assistance device 1 performs automatic driving control to enable the vehicle (hereinafter referred to as "vehicle") on which the driving assistance device 1 is installed to automatically operate without the participation of the driver and control the driving assistance system to assist the driver in driving a vehicle based on traffic conditions in the vicinity of the vehicle.

The driving assistance control may include not only driving control such as automatic steering, automatic braking, constant speed driving control, and lane keeping control, but also outputting a message prompting the driver to perform a steering operation or a deceleration operation.

[0009] The driving assistance device 1 includes external sensors 3, internal sensors 4, a positioning device 5, a map database 6, a navigation system 7, an electronic control unit (ECU) 8, a human-machine interface (HMI) 9 and executive Mechanisms 10. It should be noted that in the accompanying drawings, the map database is designated as "Map DB".

[0010] The external sensors 3 are sensors that detect the environment around the vehicle, such as an object in the vicinity of the vehicle. The external sensors 3 may include a camera 11 and a ranging device 12. The camera 11 and the ranging device 12 detect the environment around the vehicle, such as objects existing in the vicinity of the vehicle (for example, another vehicle, a pedestrian, white lines such as a lane boundary line and lane markings, and ground objects, installed on the road or in the immediate vicinity of the road, such as a traffic light, stop line, road sign, building, support, curb and pedestrian crossing), the relative position of such objects relative to the vehicle, the relative distances between the vehicle and objects, etc. .

[0011] The camera 11 may be, for example, a stereo camera. The camera 11 may be composed of monocular cameras, and by capturing images of an identical object from multiple perspectives using the monocular cameras, the distance to the object can be calculated. The distance to the object can be calculated based on the ground contact position of the object detected from the captured images obtained with the monocular cameras.

The ranging device 12 may be, for example, a laser rangefinder (LRF) or a radar.

The camera 11 and the ranging device 12 output environmental information, which is information about the detected environment, to the ECU 8 and the navigation system 7.

[0012] The interior sensors 4 are sensors that detect the driving state of the vehicle. The internal sensors 4 may include, for example, a wheel speed sensor 13 and a gyro sensor 14.

The wheel speed sensor 13 detects the wheel speed of the vehicle. The gyro sensor 14 detects the pitch rate, the roll rate and the yaw rate of the vehicle. The wheel speed sensor 13 and the gyro sensor 14 output driving state information, which is information about the detected motion state, to the ECU 8 and the navigation system 7.

[0013] The positioning device 5 receives radio waves from a plurality of navigation satellites and thus obtains the current position of the vehicle and outputs the obtained current position of the vehicle to the ECU 8 and the navigation system 7. The positioning device 5 may have, for example, a global positioning system receiver ( GPS) or another global navigation satellite system (GNSS) receiver other than a GPS receiver.

[0014] The map database 6 stores road map data. Road map data includes shapes (lane shapes) and 2D coordinates (such as latitude and longitude) of white lines, such as lane boundary lines and lane markings, road and white line elevations, 2D coordinate information (such as latitude and longitude), and also information about the height of ground objects installed on roads and in the vicinity of roads, such as traffic lights, stop lines, road signs, buildings, poles, curbs and pedestrian crossings.

The road map data may also include information about road types, road grades, number of lanes, permitted speeds (limit speeds), road width, presence or absence of intersections, and the like. Road types can include, for example, a regular road and an expressway.

The map database 6 is used by the ECU 8 and the navigation system 7.

[0015] The navigation system 7 performs route guidance to a destination that is set on the map by the vehicle driver for the vehicle passenger. The navigation system 7 estimates the current location of the vehicle using various types of information input from the external sensors 3, the internal sensors 4 and the positioning device 5, generates a route to the destination, and provides route guidance to the passenger. The navigation system 7 outputs route information to the ECU 8.

[0016] The ECU 8 estimates the current location of the vehicle and sets the target driving path on which the vehicle should move based on the estimated current location, the road map data in the map database 6, the route information output from the navigation system 7, the environment and the state of the vehicle. The ECU 8 performs automatic motion control and auxiliary motion control of the vehicle based on the predetermined target motion path, drives the actuators 10, and thereby controls the motion of the vehicle.

The external sensors 3, the internal sensors 4, the positioning device 5, the map database 6 and the ECU 8 constitute the own position estimation device 2 according to an embodiment of the invention.

[0017] ECU 8 includes a processor 15 and peripheral components such as a memory 16. The processor 15 may be, for example, a central processing unit (CPU) or a microprocessor unit (MPU).

The storage device 16 may include a semiconductor storage device, a magnetic storage device, and an optical storage device. The storage device 16 may include registers, caches, and memories such as read only memory (ROM) and random access memory (RAM) that are used as main storage.

It should be noted that the ECU 8 may be implemented with a functional logic circuit, which is implemented on a general purpose semiconductor integrated circuit. For example, ECU 8 may include a programmable logic device (PLD) such as a programmable gate array (FPGA) or the like.

[0018] HMI 9 is an interface for input and output of information between a passenger in a vehicle and a navigation system 7 and an ECU 8.

The HMI 9 may receive, for example, an input operation for entering a destination into the navigation system 7, which is performed by the passenger. The HMI 9 may, for example, output the driving guidance given by the navigation system 7 or the road guidance information based on road map data in the vicinity of the vehicle.

[0019] The actuators 10 control the steering wheel, the accelerator opening, and the braking device of the vehicle in accordance with the control signal output from the ECU 8, and thereby generate the behavior of the vehicle.

The actuators 10 include a steering actuator 17 , an accelerator opening actuator 18 , and a brake control actuator 19 .

The steering drive mechanism 17 controls the direction of rotation and the amount of rotation of the vehicle. The accelerator opening drive mechanism 18 controls the opening of the vehicle's accelerator. The brake control drive mechanism 19 controls the braking action of the vehicle's braking device.

[0020] Next, the flow of the own location estimation processing performed by the ECU 8 will be described. Reference will now be made to FIG. 2. Reference numeral 20 denotes a vehicle on which the driving aid device 1 is installed. Reference numerals 21 and 22 denote roads existing at different heights h1 and h2, respectively, reference numerals 21a and 21b denote lane boundary lines (white lines) on the road 21, and reference numerals 22a and 22b denote lane boundary lines (white lines) on road 22. The case now assumed is that the vehicle 20 is on road 21.

[0021] When the two-dimensional locations of the roads 21 and 22, which exist at different heights, are close to each other, it becomes impossible to determine which road the vehicle 20 is on based only on the two-dimensional coordinate information.

While it can be assumed that map matching is performed in 3D space (eg, the space represented by latitude, longitude, and altitude) to estimate one's own location, including height, 3D map matching is computationally expensive. Therefore, it is preferable to be able to estimate one's own location, including height, without performing 3D map matching. Accurate calculation based on wheel speed and angular velocity has been known as a technique for estimating one's own position.

[0022] However, when estimating one's own location using dead reckoning, an error is accumulated due to measurement error. Therefore, it is necessary to obtain the observed height value from some source of information and correct the estimated value calculated using exact calculus by the observed value.

Thus, the driving assistance device 1 obtains the height information of the road sign 23 near the vehicle 20 which is on the road 21 from the map database, and estimates the height at which the vehicle 20 is located based on the height information of the road sign 23 .

[0023] Specifically, the relative position of the road sign 23 with respect to the vehicle 20 is determined by the external sensors 3. The ECU 8 determines the current location of the vehicle 20. For example, the ECU 8 estimates the current location of the vehicle 20 using speed-based dead reckoning. of the wheel rotation detected by the wheel speed sensor 13, and the pitch rate, roll rate and yaw rate detected by the gyro sensor 14. For example, the ECU 8 can measure the current location of the vehicle 20 using the positioning device 5.

[0024] The ECU 8 obtains the height information of the road sign 23 from the map database 6, which records information about two-dimensional coordinates (for example, longitude and latitude) and information about the height of road signs 23 and 24 located in the vicinity of roads, based on two-dimensional coordinates of the current location of the vehicle 20 and the relative location of the road sign 23.

The ECU 8 estimates the height at which the vehicle 20 is located based on the height information obtained from the map database 6 . For example, the ECU 8 evaluates the height indicated by the height information obtained from the map database 6 as the height at which the vehicle 20 is located.

[0025] Correcting the estimated height value calculated using exact reckoning with the estimated height in this way can prevent the accumulation of an error caused by a measurement error.

In addition, since the height can be estimated without performing 3D map matching, the computational cost can be kept low.

[0026] In addition, since the height is estimated based on the coordinate information of the road sign 23 recorded in the map database 6, it is possible to correctly estimate the height at which the vehicle 20 is located even if there are respectively separate roads of the same type at different heights and a two-dimensional roads are close to each other.

It should be noted that, as shown in FIG. 2, the road sign 24 is placed on the road 22, which is at a different height than the road 21, on which the vehicle 20 is also located. However, since the road sign 24 is protected from the vehicle 20 on the road 21 by the road structure, the external sensors 3 do not can detect the road sign 24. Therefore, an erroneous estimation of the height at which the vehicle 20 is based on the height information of the road sign 24, which is installed on the road 22 different from the road 21, never occurs. Thus, the height information of the road sign does not have to be a numerical value representing the height, and it can be configured to obtain information indicating which of the roads that are close to each other has the road sign. For example, when a road sign 23 is detected, information indicating that the installation site of the road sign 23 is on the road 21 can be obtained, and it can be determined that the vehicle 20 is traveling on one of the higher-altitude roads that are close to each other. On the other hand, when the road sign 24 is detected, information indicating that the installation site of the road sign 24 is on the road 22 can be obtained, and it can be determined that the vehicle 20 is traveling on another, lower elevation, of the roads close to each other.

[0027] Next, the functional configuration of the ECU 8 will be described with reference to FIG. 3. The ECU 8 includes a self-location estimation unit 30, a target trajectory setting unit 31, and a movement control unit 32. The functions of the self-location estimation module 30, the target trajectory setting module 31, and the movement control module 32 may be implemented, for example, by the processor 15 of the ECU 8 executing computer programs stored in the memory 16.

[0028] The own position estimator 30 estimates the vehicle's own position based on various information input from the external sensors 3, the internal sensors 4 and the positioning device 5, and the information obtained with reference to the map database 6 .

The own location estimation unit 30 includes an exact reckoning unit 40, a map matching unit 41, a traffic sign detection unit 42, a coordinate calculation unit 43, and an altitude information acquisition unit 44 .

[0029] The dead reckoning unit 40 calculates the predicted position of the vehicle at the current time using the exact calculation based on the wheel speed, pitch rate, roll rate, and yaw rate detected by the internal sensors 4. The predicted vehicle position includes two-dimensional coordinates, height and azimuth of the direct direction of the vehicle.

The dead reckoning unit 40 outputs the calculated predictive location to the map matching unit 41 .

[0030] In this processing, the dead reckoning unit 40 calculates two-dimensional coordinates in the two-dimensional coordinate system used in the map database 6 . Hereinafter, the two-dimensional coordinate system used in the map database 6 is referred to as the "map coordinate system".

Although the following description will describe an example in which the 2D coordinate system used in the map database 6 is a geographic coordinate system in which coordinates are represented by latitude and longitude, the 2D coordinate system is not limited to the geographic coordinate system, and other coordinate system may be used, such as planar rectangular coordinate system and polar coordinate system.

[0031] The map matching unit 41 calculates, based on the relative position of ground objects in the vicinity of the vehicle and the relative position of the white lines that are detected by the external sensors 3, and the predicted position of the vehicle, which is calculated by the dead reckoning unit 40, two-dimensional coordinates in the coordinate system maps of ground objects and white lines.

The map matching unit 41 matches the 2D coordinates of ground objects and white lines with the map data base 6 using the 2D map matching, and calculates a vehicle location matching correction value for each of latitude, longitude, and azimuth.

[0032] The map matching unit 41 corrects the predicted vehicle location, which is calculated by the dead reckoning unit 40, using the calculated display correction values, and thus obtains an estimated value of the current vehicle location.

The map matching unit 41 outputs the current location estimate of the vehicle to the coordinate calculation unit 43 and the target trajectory setting unit 31 .

[0033] The traffic sign detection unit 42 detects the relative location of the traffic sign, which is detected by the external sensors 3, in the immediate vicinity of the vehicle with respect to the vehicle. The X-coordinate and Y-coordinate of the relative location of the road sign are referred to as "TS_X [m]" and "TS_Y [m]", respectively.

The traffic sign detection unit 42 outputs the relative position of the traffic sign to the coordinate calculation unit 43 .

[0034] The coordinate calculation unit 43 calculates the estimated values of the two-dimensional coordinates of the road sign in the map coordinate system.

As shown in FIG. 4, the latitude and longitude of the road sign are denoted as "TS_B [rad]" and "TS_L [rad]", respectively.

The latitude and longitude of the estimated value of the current position of the vehicle and the azimuth of the forward direction of the vehicle, which are obtained by the map matching unit 41, are indicated as "V_B [rad]", "V_L [rad] and "Ɵ [rad]", respectively.

[0035] The coordinate calculation unit 43 calculates the estimated values of the two-dimensional coordinates (TS_B [rad], TS_L [rad]) of the road sign by approximation according to the following formulas (1) and (2):

In the formulas above, M denotes the radius of curvature of the meridian [m] and N denotes the radius of curvature of the main vertical [m] at latitude V_B.

The coordinate calculation unit 43 outputs the estimated values of the two-dimensional coordinates (TS_B [rad], TS_L [rad]) of the road sign to the elevation information acquisition unit 44 .

[0036] The height information acquisition unit 44 compares the 2D coordinates (TS_B[rad], TS_L[rad]) of the road sign calculated by the coordinate calculation unit 43 with the 2D road sign coordinate information stored in the map database 6 .

When a road sign that has two-dimensional coordinate information that corresponds to two-dimensional coordinates (TS_B [rad], TS_L [rad]) that are calculated by the coordinate calculation unit 43 exists in the map database 6, the height information acquisition unit 44 obtains information about coordinates (latitude TS_M_B [rad], longitude TS_M_L [rad] and height TS_M_H [m]) of the corresponding road sign from the map database 6 .

[0037] In the above processing, the cases where the 2D coordinates (TS_B[rad], TS_L[rad]) and the 2D coordinates (TS_M_B[rad], TS_M_L[rad]) coincide with each other include not only the case where the two 2D coordinates the coordinates completely match each other, but also the case when the difference between two two-dimensional coordinates is less than a given value.

The height information (TS_M_H [m]) of the road sign may be information about the height of the ground (ie, the base) at the installation point of the road sign or information about the height of the sign plate of the road sign.

[0038] It should be noted that the road sign whose height information is to be obtained may be, for example, an information sign, a hazard warning sign, a regulatory sign, or a directional sign.

The height information acquisition unit 44 judges that the height at which the vehicle is located is the height indicated by the road sign height information obtained from the map database 6 . The height information acquisition unit 44 may update the height estimate at which the vehicle is located using the Kalman filter based on the road sign height information acquired a plurality of times at different points in time.

The height information acquisition unit 44 outputs the estimated height at which the vehicle is located to the dead reckoning unit 40 and the target trajectory setting unit 31 .

[0039] Dead reckoning unit 40 corrects the predicted value of the height at which the vehicle is located, which is calculated using dead reckoning, in accordance with the height estimated by the height information obtaining unit 44 . For example, dead reckoning unit 40 corrects (rewrites) the predicted value of the height at which the vehicle is located, which is calculated using dead reckoning, with the height estimated by the height information obtaining unit 44, and calculates a subsequent predicted vehicle location based on the corrected height.

The dead reckoning unit 40 may correct the predicted value of the height at which the vehicle is located, which is calculated using dead reckoning, according to the height estimated by the height information obtaining unit 44 each time the vehicle travels a predetermined distance. This configuration can effectively correct the dead reckoning error that accumulates with the distance travelled.

[0040] The target trajectory setting unit 31 sets the target trajectory to be followed by the vehicle based on the current location of the vehicle estimated by the map matching unit 41, the road map data in the map database 6, the route information output from the navigation system 7 , the environment detected by the external sensors 3, and the driving state of the vehicle detected by the internal sensors 4.

In this case, the target trajectory setting unit 31 determines the road on which the vehicle is located based on the two-dimensional coordinates of the current location of the vehicle estimated by the map matching unit 41 and the estimated height at which the vehicle is located by the height information acquisition unit 44. For example, when a plurality of roads whose heights differ from each other exist in the two-dimensional coordinates of the current location of the vehicle, the target path setting block 31 determines which of the plurality of roads the vehicle is on based on the height at which the vehicle is located, which is estimated by the block 44 get altitude information.

The target trajectory setting unit 31 sets the target trajectory along which the vehicle travels on the road it is on according to the route created by the navigation system 7.

[0041] The target trajectory setting block 31 outputs the predetermined target motion trajectory to the motion control block 32 .

The driving control unit 32 performs automatic driving control and driving assistance control of the vehicle by driving the actuators 10 so that the vehicle moves along the driving path generated by the target trajectory setting unit 31, and thereby drives the steering mechanism, the mechanism acceleration and braking mechanism of the vehicle.

Work

[0042] Next, an example of the driving assistance method according to the embodiment will be described with reference to FIG. 5.

In step S1, the own location estimator 30 of FIG. 3 performs own location estimation processing for estimating the current location of the vehicle.

[0043] FIG. 6 is a flowchart of an example of own location estimation processing S1.

In step S10, dead reckoning unit 40 calculates the predicted position (latitude, longitude, altitude, and azimuth) of the vehicle at the current time using dead reckoning based on wheel speed, pitch rate, roll rate, and yaw rate determined by the internal sensors 4 .

In step S11, the map matching unit 41 calculates, based on the relative positions of ground objects in the vicinity of the vehicle and the relative positions of the white lines that are detected by the external sensors 3, the predicted position of the vehicle that has been calculated by the dead reckoning unit 40 and the map database 6, an estimated value the current location of the vehicle using 2D map matching.

[0044] In step S12, the traffic sign detection unit 42 determines the relative location (TS_X [m], TS_Y [m]) of the traffic sign that is detected by the external sensors 3 in the vicinity of the vehicle with respect to the vehicle.

In step S13, the coordinate calculation unit 43 calculates estimated values (TS_B[rad], TS_L[rad]) of the two-dimensional coordinates of the road sign in the map coordinate system.

[0045] In step S14, the height information acquisition unit 44 compares the 2D coordinates (TS_B[rad], TS_L[rad]) of the road sign calculated in step S13 with the 2D coordinate information of the road signs recorded in the map database 6 . The height information acquisition unit 44 determines whether there exists in the map database 6 a road sign that has 2D coordinate information matching the 2D coordinates (TS_B [rad], TS_L [rad]).

[0046] When there is no road sign whose 2D coordinates match the 2D coordinates (TS_B[rad], TS_L[rad]) in the map database 6 (step S14: N), own location estimation processing S1 ends without height correction calculated with using exact calculus.

When a road sign whose two-dimensional coordinates match the two-dimensional coordinates (TS_B [rad TS_L [rad]) exists in the map database 6 (step S14: Y), the process proceeds to step S15.

[0047] In step S15, the height information acquisition unit 44 obtains the coordinate information (latitude TS_M_B [rad], longitude TS_M_L [rad], and height TS_M_H [m]) of the road sign whose two-dimensional coordinates correspond to the two-dimensional coordinates (TS_B [rad], TS_L[rad]) from map database 6. The height information acquisition unit 44 judges that the height at which the vehicle is located is the height (TS_M_H [m]) of the road sign.

In step S16, dead reckoning module 40 corrects the predicted value of the height at which the vehicle is located, which was calculated using dead reckoning, by the height estimated by the height information obtaining module 44 . Subsequently, the own location estimation processing S1 is terminated.

[0048] Reference will now be made to FIG. 5. In step S2, the target trajectory setting block 31 determines the road on which the vehicle is located based on the two-dimensional coordinates of the current location of the vehicle, which was estimated by the map matching block 41, and the height at which the vehicle is present, which was estimated by block 44 get altitude information.

When a plurality of roads whose heights differ from each other exist in the two-dimensional coordinates of the current location of the vehicle, the target path setting block 31 determines which of the plurality of roads the vehicle is on based on the height at which the vehicle is located, which was estimated by the block 44 get altitude information. It should be noted that the vehicle height information is required only as information that can determine which of the plurality of roads whose heights are different from each other, the vehicle is located in the two-dimensional coordinates of the current location of the vehicle. For example, the vehicle height information may be information that indicates which of the plurality of different roads the traffic sign is set to, among the traffic signs respectively set on the plurality of roads to which the traffic sign detected by the vehicle corresponds.

[0049] In step S3, the target trajectory setting unit 31 sets the target trajectory along which the vehicle is traveling on the road it is currently on, based on the current location of the vehicle, which was estimated by the map matching unit 41, road map data in the map database 6, the route information output from the navigation system 7, the environment detected by the external sensors 3, and the driving state of the vehicle detected by the internal sensors 4.

In this case, the target trajectory setting unit 31 sets the target trajectory along which the vehicle travels on the road on which the vehicle is located, which was determined in step S2, in accordance with the route created by the navigation system 7.

[0050] In step S4, the motion control unit 32 performs motion control, such as automatic traffic control and driving assistance control, of the vehicle by operating the actuators 10 so that the vehicle moves along the driving path that was generated by the unit 31 setting the target trajectory.

Advantageous Effects of the Embodiment

[0051] (1) The traffic sign detection unit 42 detects a traffic sign in the vicinity of the vehicle. Block 40 accurate reckoning and block 41 mapping map determine the current location of the vehicle. The coordinate calculation unit 43 and the height information acquisition unit 44 acquire the height information of the detected road sign from the map database 6 based on the relative position of the detected road sign relative to the vehicle and the current location, and estimate the height at which the vehicle is located according to the height information .

Since this processing makes it possible to estimate the height at which the vehicle is located, it becomes possible to determine which of the roads existing at different heights the vehicle is on.

In particular, since the height is estimated based on the coordinate information of the road sign 23 recorded in the map database 6, it is possible to correctly estimate the height at which the vehicle 20 is located even if the same type of roads respectively exist at different heights and their two-dimensional arrangement is close. to each other.

[0052] (2) The dead reckoning unit 40 and the map matching unit 41 determine the two-dimensional coordinates of the current location in the map coordinate system. The coordinate calculation unit 43 calculates the 2D coordinates of the detected road sign in the map coordinate system based on the 2D coordinates of the relative location of the detected road sign and the current location. The height information acquisition unit 44 obtains the height information of the road sign, which has two-dimensional coordinate information corresponding to the two-dimensional coordinates of the detected road sign from the map database 6, as the height information of the detected road sign.

This processing makes it possible to obtain height information of a road sign detected in the vicinity of a vehicle from a map database 6 in which two-dimensional coordinate data and height information of road signs existing in the vicinity of roads are recorded.

[0053] (3) The map matching unit 41 calculates the 2D coordinates of the current location in the map coordinate system using the 2D map matching.

That is, the map matching unit 41 calculates the 2D coordinates of the current location using the 2D map matching, and estimates the height at which the vehicle is located based on the coordinate information of the road sign 23 stored in the map database 6 . Since, with this configuration, one's own location, including height, can be estimated without performing a 3D map matching, a low computational cost can be maintained.

[0054] (4) Dead reckoning unit 40 corrects the estimated value of the height at which the vehicle is located, which is calculated using dead reckoning, in accordance with the height information obtained from the map database 6 .

This configuration prevents the accumulation of height error caused by measurement error.

[0055] (5) The dead reckoning unit 40 corrects the estimated value according to the height information obtained from the map database every time the vehicle travels a predetermined distance.

Such a configuration can effectively correct the dead reckoning error that accumulates as the path increases.

[0056] (6) The traffic sign that the traffic sign detection unit 42 detects may be an information sign. Such information signs are often installed at vertical intersections of roads, for example, at intersections. Therefore, it is possible to properly determine which of the roads the vehicle is traveling on in the section where the roads cross each other vertically.

[0057] All examples and conventions provided herein are for aiding purposes to help the reader understand the invention and the concepts introduced by the inventor in the development of the art, and they should not be construed as limitations to such specifically listed examples and conditions, but the organization of such examples in the description is not intended to demonstrate the superiority or inferiority of the present invention. While one or more embodiments of the present invention have been described in detail, it should be understood that various changes, substitutions and modifications may be made to the invention without departing from the spirit and scope of the present invention.

List of reference positions

[0058] 1 - driving assistance device

2 - device for estimating own location

3 - external sensor

4 - internal sensor

5 - positioning device

6 - map database

7 - navigation system

10 - actuator

11 - camera

12 - device for determining the range

13 - wheel speed sensor

14 - gyro sensor

15 - processor

16 - storage device

17 - steering drive mechanism

18 - accelerator opening drive mechanism

19 - brake control drive mechanism

20 - vehicle

21, 22 - road

21a, 21b, 22a, 22b - lane boundary line (white line)

23, 24 - road sign

30 - own location estimation block

31 - target trajectory setting block

32 - motion control unit

40 - exact number block

41 - card matching block

42 - traffic sign detection unit

43 - block for calculating coordinates

44 - block for obtaining information about the height.

Claims (26)

1. Method for estimating own location, including: detection of a road sign near the vehicle; determining the current location of the vehicle; obtaining information about the height of the detected road sign from map data in which the 2D coordinate information of the road lane and the 2D coordinate information and height information of the road sign adjacent to the road are recorded based on the relative position of the detected road sign relative to the vehicle and the current location; estimating the height at which the vehicle is located according to the height information obtained from the map data; determining when a plurality of roads whose heights are different from each other is in the 2D coordinate of the current location of the vehicle, on which one of the plurality of roads the vehicle is located, based on the estimated height; setting the target trajectory of the vehicle based on the 2D lane coordinate and the 2D coordinate of the current location of the vehicle so that the vehicle travels along the route in the 2D coordinate system generated by the navigation system on the lane of the plurality of roads on which the vehicle is located; and actuating an actuator to control the steering mechanism of the vehicle so that the vehicle moves along the target path. 2. The method of estimating own location according to claim 1, including: determining a two-dimensional coordinate of the current location in the map data coordinate system; calculating a two-dimensional coordinate of the detected traffic sign in a coordinate system based on a two-dimensional coordinate of the relative location of the detected traffic sign and the current location; and obtaining traffic sign height information having 2D coordinate information corresponding to the 2D coordinate of the detected traffic sign from the map data as the detected traffic sign height information. 3. The method of estimating own location according to claim 2, including calculating a two-dimensional coordinate of the current location in a coordinate system using a comparison of a two-dimensional map. 4. The own position estimation method according to any one of claims 1 to 3, including correcting the estimated value of the height at which the vehicle is located, wherein the estimated value is calculated using dead reckoning in accordance with the altitude information obtained from the map data. 5. The own location estimation method according to claim 4, including adjusting the estimated value according to the altitude information obtained from the map data each time the vehicle travels a predetermined distance. 6. A method for estimating one's own location according to any one of claims 1 to 5, wherein the road sign is an information sign. 7. A device for estimating own location, comprising: a sensor configured to detect a traffic sign near the vehicle, a drive mechanism for controlling the steering mechanism of the vehicle and controller configured to: - determining the current location of the vehicle; - obtaining information about the height of the detected traffic sign from the map data in which the information about the two-dimensional coordinates of the road lane and the information about the two-dimensional coordinates and information about the height of the traffic sign adjacent to the road are recorded, based on the relative position of the detected traffic sign relative to the vehicle and the current location ; - estimates of the height at which the vehicle is located, according to the height information obtained from the map data; - determining, when in two-dimensional coordinates of the current location of the vehicle, there are a plurality of roads, the heights of which differ from each other, on which one of the plurality of roads the vehicle is located, based on the estimated height; - setting the target trajectory of the vehicle based on the 2D coordinate of the lane and the 2D coordinate of the current location of the vehicle so that the vehicle moves along the route in the 2D coordinate system generated by the navigation system on the lane of the plurality of roads on which the vehicle is located; and - actuating the actuator to control the steering mechanism of the vehicle so that the vehicle moves along the target trajectory.

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