JP2003296899A - Preceding vehicle determining device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To determine a preceding vehicle even when the attitude information with respect to a road of its own vehicle is not accurate. <P>SOLUTION: By a radar device 101 and a radar signal processor 102, for the preceding vehicle A, a distance LA<SB>i</SB>to its own vehicle and a direction ϕA<SB>i</SB>are obtained and preserved in a traveling history preservation means 301. From a GPS device 201, its own vehicle position estimation means 202 and road map data 203, the position of its own vehicle P<SB>i</SB>is calculated and preserved in the traveling history preservation means 301. A radius of curvature of road acquisition means 210 calculates the radius of curvature of the traveling road in front and outputs it to a shape comparison means 303. In a preceding vehicle traveling track curvature radius estimation means 302, the set of data at three points of the time is read from the traveling history preservation means 301 and the radius of curvature of the traveling track is calculated and outputted to the shape comparison means 303. In such a manner, the curvature radius of the road and the radius of curvature of the traveling track of the preceding vehicle are compared and whether or not the preceding vehicle travels on the same lane as its own vehicle is judged. <P>COPYRIGHT: (C)2004,JPO

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention is mounted on a vehicle,
The present invention relates to a preceding vehicle determination device that determines whether or not a preceding vehicle ahead is traveling in the same lane as the vehicle currently traveling while traveling on a road with multiple lanes.

[0002]

2. Description of the Related Art While traveling on a road with a plurality of lanes, which is not curved at the present position of the host vehicle and is curved forward, a preceding vehicle ahead is traveling in the same lane as the host vehicle is currently driving. For example, a detection device described in Japanese Patent Laid-Open No. 2000-187800 is known as a device for determining whether or not it is inside. This technique is for predicting a curving traveling road using road shape data, since a curving traveling road cannot be predicted only by the steering angle of the own vehicle.

[0003]

By the way, the so-called G
In a vehicle equipped with PS, the position itself of the vehicle can obtain relatively accurate data, that is, the direction itself of the vehicle body of the vehicle cannot be obtained accurately. Therefore, it is determined that the preceding vehicle traveling ahead of the lane in which the vehicle is traveling is not the preceding vehicle, or conversely, the vehicle traveling ahead in the lane next to the lane of the vehicle is determined to be the preceding vehicle. Will be done. That is, all of the detected position of the front obstacle, the road shape, the position of the vehicle on the road shape data (map), and the vehicle body direction (posture) had to be acquired very accurately.

The present invention has been made to solve the above problems, and overcomes the above problems by paying attention to the radius of curvature of the road, which is an important feature among the road shapes. Another aspect of the present invention is to calculate a road shape as an arc or another curve, and determine a preceding vehicle in which the distance between the road shape curve and the traveling history is equal to or less than a predetermined value or minimum when the vehicle direction is changed. It is determined that the vehicle is traveling in the same lane as the current lane.

[0005]

In order to solve the above-mentioned problems, according to the means described in claim 1, it is mounted on a vehicle,
While traveling on a road with multiple lanes, a preceding vehicle determination device that determines whether or not a preceding vehicle ahead is traveling in the same lane as the vehicle is currently traveling, searches ahead and detects if there is an obstacle. Front obstacle detection means for detecting the distance from the vehicle to the obstacle and the direction from the own vehicle; and own vehicle position acquisition means for detecting the position of the own vehicle with respect to the road map by collating with the road map data. , A road curvature radius acquisition means for acquiring the curvature radius of the road from the road map data, the distance of the preceding vehicle ahead detected by the front obstacle detection means from the own vehicle, the direction from the own vehicle, and the own vehicle position The traveling history of the preceding vehicle is obtained from the position of the own vehicle obtained by the obtaining means, and the preceding vehicle is obtained from the curvature radius of the road at the position corresponding to the traveling history of the preceding vehicle output by the road curvature radius obtaining means. There and having a determining preceding vehicle judgment means whether traveling lane same lane which the vehicle is currently traveling.

According to the second aspect of the invention, the preceding vehicle determining means determines the distance from the own vehicle to the preceding vehicle ahead detected by the front obstacle detecting means, the direction from the own vehicle, and the own vehicle. Travel history storage means for storing the position of the own vehicle obtained by the vehicle position acquisition means, and preceding vehicle travel trajectory curvature radius estimation means for estimating the curvature radius of the travel trajectory of the preceding vehicle from the data of the travel history storage means. , A shape comparison means for comparing the curvature radius of the road curvature radius acquisition means with the curvature radius of the preceding vehicle traveling trajectory curvature radius estimation means.

According to a third aspect of the present invention, curvature radius data is included as road map data. Further, according to the means of claim 4,
The curvature radius data included in the road map data includes a plurality of curvature radius data at a connection portion between the road and the road such as an intersection where the curvature is discontinuous, and the relative shape of the road is determined by the entire curvature radius data. It is characterized by being reproducible. According to the means of claim 5,
The road map data has no curvature radius data, and the curvature radius of the road is calculated from the road shape.

According to the means of claim 6, whether or not the preceding vehicle in front of the vehicle mounted on the vehicle is traveling in the same lane as the vehicle currently traveling is traveling on a road having a plurality of lanes. In the preceding vehicle determination device for determining the, the front obstacle detection means for detecting the distance from the own vehicle to the obstacle when an obstacle is present and the direction from the own vehicle, and road map data By collating, the own vehicle position acquisition means for detecting the position of the own vehicle with respect to the road map, the distance from the own vehicle of the preceding vehicle ahead detected by the front obstacle detection means, the direction from the own vehicle, A curve showing the shape of the road on which the travel history acquisition means obtains a travel history of a predetermined number of preceding vehicles from the position of the travel vehicle obtained by the travel vehicle position acquisition means, and the coordinate system is set. Calculate A road curve calculating means and a traveling history of a predetermined number of preceding vehicles when the own vehicle changes its direction are converted into the coordinate system to show the shape of the traveling road fixed on the coordinate system. The preceding vehicle that minimizes the distance to the curve and the direction of the own vehicle are determined, and if the distance is less than or equal to a predetermined value under the conditions, the preceding vehicle is traveling in the same lane as the own vehicle is currently driving. And a preceding vehicle determining means for determining that there is a vehicle.

Further, the means according to claim 7 is characterized in that the road curve calculating means calculates an arc indicating the shape of the traveling road.

[0010]

[Advantageous Effects of the Invention] Even if the radius of curvature of the road ahead and the radius of curvature of the road at the present position of the host vehicle are different and the preceding vehicle cannot be sufficiently determined depending on the steering angle, the road map data and the host vehicle are obtained. The road data ahead can be extracted from the position of the own vehicle by the position acquisition means. For example, when detecting a front obstacle such as a preceding vehicle with a radar device, the yaw angle and offset position of the host vehicle with respect to the lane cannot be acquired, and therefore the road shape in front and the traveling history of the preceding vehicle cannot be directly compared. However, relative comparison is possible. Therefore, it is possible to compare the curvature radius, which is a feature of the road shape, with the curvature radius of the traveling locus of the preceding vehicle, and from this, determination of the preceding vehicle by relative comparison, that is, the preceding vehicle is the same as the lane in which the vehicle is currently traveling. It is possible to use the preceding vehicle determination device that determines whether or not the vehicle is traveling in the lane. Using the traveling history also reduces the detection error of the radar, for example.

Further, a coordinate system is set, a curve showing the shape of a traveling road on the coordinate system is calculated, and a traveling history of a predetermined number of points of the preceding vehicle when the own vehicle changes its direction is given as the coordinate. If it is determined that the preceding vehicle traveling in the same lane as the host vehicle is the one that is converted into the system and minimizes the distance to the curve showing the shape of the traveling road fixed on the coordinate system to a predetermined value or less. For example, even if the radius of curvature is not used as an index and the direction of the host vehicle deviates from the direction of the road on which the vehicle is traveling, highly accurate determination is possible.

[0012]

BEST MODE FOR CARRYING OUT THE INVENTION The features of the present invention will be described below in comparison with the prior art with reference to the drawings.

[First Embodiment] FIG. 1 is a block diagram showing the configuration of a preceding vehicle determination apparatus according to a first specific embodiment of the present invention. The preceding vehicle determination device of FIG. 1 includes four blocks, which are a front obstacle detection unit 100, a vehicle position acquisition unit 200, a road curvature radius acquisition unit 210, and a preceding vehicle determination unit 300. In addition, the front obstacle detecting means 100
Is a radar device 101 and a radar signal processing device 102, and the vehicle position acquisition means 200 is a GPS device 201,
It is composed of the own vehicle position estimating means 202 and the road map data 203, and the preceding vehicle determining means 300 is the traveling history storage means 3.
01, a preceding vehicle traveling locus curvature radius estimating means 302 and a shape comparing means 303.

At time i, the radar signal processing device 102 processes the radar signal received by the radar device 101 and reflected by the front obstacle, and the front obstacle A, i.e., the preceding vehicle A, is processed at time i with respect to the host vehicle. distance L _Ai in the direction phi _Ai at time i with respect to the vehicle is stored is calculated in the travel history storing means 301. Further, at the same time i, the own vehicle position estimating means 202 reads the road map data 203 from the data of the GPS device 201, calculates the position P _{i of the} own vehicle, and the traveling history storing means 30.
Saved in 1.

On the other hand, the position P _{i of the} host vehicle is also output to the road curvature radius acquisition means 210, the road curvature radius acquisition means 210 calculates the curvature radius of the forward traveling road together with the road map data 203, and the shape comparison means. It is output to 303.

In the preceding vehicle judging means 300, first, from the traveling history storing means 301, a data set at three times, that is, the distance L _Ai , the direction φ _Ai , and the own vehicle's own vehicle are decided so as to determine, for example, three points of the preceding vehicle A. The position P _i is read and output to the preceding vehicle traveling locus curvature radius estimating means 302 and the shape comparing means 303. In the preceding vehicle traveling locus curvature radius estimating means 302, the radius of curvature of the traveling locus is calculated from the data set at the three times and is output to the shape comparing means 303.

The shape comparing means 303 compares the radius of curvature of the traveling locus of the preceding vehicle with the radius of curvature of the road to determine whether the preceding vehicle is traveling in the same lane as the own vehicle is currently traveling. To do.

The effect of the present invention will be described with reference to FIGS.
Of these, FIG. 4 is the present invention, and FIGS. 2 and 3 are conventional techniques.
It shows the problem in. Own vehicle only by steering angle
To determine the direction of travel of the vehicle,
Position P_nowIs in the straight part of the road,
Starting point C_sIf there is a preceding vehicle A or B that exceeds the
Both A cannot be judged to be the preceding vehicles in the same lane, so
Vehicle B traveling in the same lane is determined to be a vehicle in the same lane
Will be done. That is, the first lane in which the vehicle is traveling
(SL₁To CL₁Vehicles that are driving
It is A, but its position is the current position P of the own vehicle._nowTo
Driving direction D of own vehicle_nowNot on top. On the other hand,
First lane to drive (SL₁To CL₁Second next to
Lane (SL ₂To CL₂Preceding vehicle that is traveling
B is the current position P of the vehicle_nowOf own vehicle in Japan
Direction D_nowIt is above. In this way, for example, your vehicle runs straight
And the preceding vehicle is traveling on a curve,
Direction of travel D_nowSame as above (or within the range around it)
The preceding vehicle is the technology that determines that the vehicle is a preceding vehicle traveling on one lane.
Both will be mistaken.

On the other hand, FIG. 3 shows Japanese Patent Laid-Open No. 2000-187800.
Although it is a technique described in the official gazette, when the road is recognized as R _im (three solid lines) because the own vehicle is facing diagonally with respect to the actual road R _ex (three dotted lines), The preceding vehicle A on the first lane (SL ₁ to CL ₁ )
But on the second lane (SL ₂ to CL ₂ ), the preceding vehicle B
Lane exists, but it was mistakenly recognized as the first lane (SL ' ₁ to C
It will be erroneously determined that there is the preceding vehicle B above (up to L' ₁ ).

On the other hand, in the present invention shown in FIG. 4, the positions P ₀ , ..., P _n-1 , P _n of the own vehicle and the positions of the preceding vehicle A at times 0, ..., N-1, n. A ₀ , ..., A
_n-1 , A _n , positions B ₀ , ..., B _n-1 , B _n of the preceding vehicle B are calculated, and radii of curvature at the positions A ₀ , ..., A _n-1 , A _n of the preceding vehicle A, position B ₀ of the preceding vehicle _{B, ..., B n-1} , B n radius of curvature, i.e. the preceding vehicle a, the radius of curvature R _a of the travel locus of B, R _B
By calculating, it is possible to easily compare with the road curvature radius R _data obtained from the road map corresponding to the position. While the prior art in FIG. 3 determines the preceding vehicle by absolute comparison with the road shape, the present invention in FIG. 4 determines the preceding vehicle by the relative comparison with the radius of curvature, so to speak, the road shape. . In comparison with the road curvature radius R _data , the distance between the point train forming the road and the host vehicle is incorporated to determine whether or not there is a preceding vehicle ahead of the lane of the host vehicle. That is, if the distance between the train of points forming the road and the host vehicle is 3 m to the left when viewed from the road, the road curvature radius R _data is m for left turn.
The minus 3m of units of R _data, the preceding vehicle A, the radius of curvature R _A of the travel locus of B, and compared with R _B. In addition, when calculating the road curvature radius with positive left turn and negative right turn,
The distance between the column and the vehicle that forms the road, if viewed from the road is a left -3m (rightward 3m), the m unit in the case of a right turn for the road curvature radius R _data R _data Add 3m to (negative value) (minus -3m)
The radii of curvature R _A and R _B (both are negative values) are compared.

FIG. 5 shows a case where the road map 203 includes data on the radius of curvature at each position on the road.
In FIG 5 shows a case where the point _{P i-2, P i-} 1, P i, 4 points P i _{+ 1} is, to have the same radius of curvature R _a. That is, a point P ₀ on the road (coordinates (x ₀ , y ₀ ), the same hereinafter), ..., Point P _i-2 (x _i-2 , y _i-2 ), point P _i-1 (x _{i- 1} , y _i-1 ), point P _i (x _i ,
y _i ), point P _{i + 1} (x _{i + 1} , y _{i + 1} ), ..., _{n up to} point P _n (x _n , y _n ).
For +1 point, the radius of curvature is provided as map data together with the coordinates. At this time, for example, an attribute data item may be provided and information for distinguishing a straight line, a clothoid, or an arc may be provided.

When the map data 203 is the map data 2031 having the data as shown in FIG. 5, the road curvature radius acquisition means 210 of FIG. 1 has the configuration of the road curvature radius acquisition means 210a shown in FIG. You can The road curvature radius acquisition means 210a in FIG.
11 and curvature radius data extraction means 212. The coordinates (x _g , y _g ) of the own vehicle position P _g are output from the own vehicle position estimation device 202 to the corresponding position extraction means 211 on the map. Map on the appropriate position extracting means 211 matches the road map data 2031 and the vehicle position P _g or, extracting the coordinates of the position closest to P _g. If it is on a road, 3 to several coordinate points of the road in the traveling direction are output to the curvature radius data extracting means 212, and the curvature radius data extracting means 212 extracts the corresponding position on the map 211 from the road map data 2031. The respective radii of curvature corresponding to the coordinates that are the output of the above are read.

The map data 2031 as shown in FIG.
The coordinates of the discrete points of (x_i, y_i) And radius of curvature R_iOnly have
Therefore, the coordinates (x_i,
y_i) And own vehicle position P_gCoordinates of (x_g, y_g) Does not match
Can occur frequently. In FIG. 7, point P ₀(Coordinates (x₀, y₀), The same below
D), ..., Point P_i-2(x_i-2, y_i-2), Point P_i-1(x_i-1, y_i-1),
Point P_i(x_i, y_i), Point P_{i + 1}(x_{i + 1}, y_{i + 1}), ..., Point P_n(x_n, y_n)
Are coordinates on the road, each of which has data of radius of curvature
Shall be. Own vehicle coordinates (x_g, y_g), Your vehicle is on the road
If it is determined to be above, point P on the road_sMore progress
Point in front of you, eg 4 points P_i-2, P_i-1, P_i, P_{i + 1}Zodiac
Mark (x_i-2, y_i-2), (X_i-1, y_i-1), (X_i, y_i), (X_{i + 1}, y_{i + 1})But
Extraction of curvature radius data from the corresponding position extraction means 211 on the map
It is output to the means 212 and the curvature radius data extraction means 212.
Then the coordinates (x_i-2, y_i-2), (X_i-1, y_i-1), (X_i, y_i), (X_{i + 1}, y
_{i + 1}) Four curvature radius data R corresponding to_i-2, R_i-1, R
_i, R_{i + 1}Is output. After this, the point sequence of the road is formed
Road curve and own vehicle position P_gCoordinates of (x_g, y_g) Or
, Vehicle position P_gPosition of the road curve of
Thereby, the curvature radius data is corrected. Thus the road
Curvature radius data is the curvature of the lane where the vehicle is located
Corrected to radius data.

On the other hand, as shown in FIG. 8, the road map data 203 having only the coordinates of each point as the point data on the road.
2 is used, the road curvature radius acquisition means 210 of FIG.
May be configured as the road curvature radius acquisition means 210b shown in FIG. That is, the road curvature radius acquisition means 210b includes a map relevant position extraction means 211, a peripheral shape data extraction means 213, and a curvature radius calculation means 214. The coordinates (x _g , y _g ) of the own vehicle position P _g are output from the own vehicle position estimation device 202 to the corresponding position extraction means 211 on the map. Map on the appropriate position extracting means 211 matches the road map data 2031 and the vehicle position P _g or, extracting the coordinates of the position closest to P _g. If this is on a road, the peripheral shape data extraction means 213 outputs three or several coordinate points of the road in the traveling direction to the curvature radius calculation means 214, and the curvature radius calculation means 214 outputs the peripheral shape data extraction means 213. The radius of curvature is calculated from the output coordinates of the coordinates. It is possible to calculate the position of the own vehicle position P _g with respect to the road curve and correct the radius of curvature data by this, that is, to correct the radius of curvature data of the road curve to the radius of curvature data of the lane in which the own vehicle is located. This is the same as the curvature radius data extraction means 212.

The outline of the calculation of the radius of curvature is shown in FIGS.
Shown in. In FIG. 10, it is obtained as the radius of a circle passing through three points. Curvature at the point P _i radius three P _i-1, P _i, P
_It is calculated as the radius of the circle passing through _{i + 1} . FIG. 11 shows an example using a spline curve. As the one shown in FIG. 11, specifically, a cubic curve passing through four points may be used.

When the radius of curvature is calculated from three points by any of these methods, the three points P _i-3 , P _{i -2} , and P _i-1 to the point P are obtained.
radius R _i-2, 3-point P _i-2 in _{i-2, P i-1} , the radius R _i-1, 3-point from P _i at point _{P i-1 P i-1} , P i, P i + The radius R _{i at the} point P _i may be calculated from ₁ . Further, in order to reduce the amount of calculation, the three points P _i-3 , P _i-2 , and P _i-1 to the radius of curvature R _i-2 , the three points P _i , P _{i + 1} , and P _{i +. The} radius of curvature R _{i + 1 of} the three points may be obtained from ₂ . In the case of a cubic curve that passes through four points, a cubic curve of four points y = ax ³ + bx ² + cx + d may be obtained for each 4 points that do not overlap, and every 3 points so that the slopes match at the connection points. You may ask. When capturing a road as a function of coordinates, the radius of curvature is y'and y '' is 1 by the x of y.
It is calculated as {1+ (y ') ² } ^3/2 / y''as the derivative of the first and second floors.

Next, the processing contents of the preceding vehicle determining means 300 of FIG. 1 will be described with reference to FIGS. As shown in FIG. 12, the own vehicle position P, the distances L _A and L _{B of} the preceding vehicles A and B from the own vehicle, and the azimuth angles φ _A and φ _B are set at time i, i + 1, and
It is calculated at i + 2 and saved as a travel history. As a result, as shown in FIG. 12, the positions P _i , P _{i + 1} and P _{i + 2} of the host vehicle are obtained.
And the corresponding positions A _i , A _{i + 1 of} the preceding vehicle,
A _{i + 2} , B _i , B _{i + 1} and B _{i + 2} can be calculated.

Thus, at time i, i + 1, i + 2
Position A of the preceding vehicle_i, A_{i + 1}, A _{i + 2}To preceding vehicle A
Radius of curvature R_ABut the position B of the preceding vehicle_i, B
_{i + 1}, B _{i + 2}To the radius of curvature R of the trajectory of the preceding vehicle B_BBut
Each can be calculated, and the curvature half of the lane where the vehicle is located can be calculated.
Diameter data R_DATABy comparing with
It is possible to determine whether the preceding vehicle traveling on the same lane
Can be set.

FIG. 14 is a flowchart showing the operation of the preceding vehicle determining means. Incidentally, some block diagrams are combined. A part indicated by S and a three-digit number like S000 is a flowchart part of the operation of the preceding vehicle judging means. At time t _i , the own vehicle position acquisition means 200 and the road curvature radius acquisition means 210 have previously calculated the curvature radii R _DATA of the lanes of the plurality of own vehicles up to the distance L _set ahead. On the other hand, the outputs of the radar signal processing device 102 and the own vehicle position estimation means 202 are stored in the travel history storage means 301. In step S002, at time t _i ,
If the number of running history saved is less than 3, step S
Returning to 001, the outputs of the radar signal processing device 102 and the own vehicle position estimating means 202 are repeatedly stored in the travel history storing means 301. If the number of times the traveling history is stored is 3, the process proceeds to step S003, and based on the traveling history of the preceding vehicle N, the three coordinates (Nx (ti), Ny) of the traveling locus.
(ti)) is calculated. Next, in step S004, the radius of curvature R of the travel locus is calculated by arc fitting from the three coordinates.
Calculate _est . At this time, the radius of curvature R of the traveling locus
It is assumed that _est is a distance Ln ahead of the current position of the host vehicle, and is processed in the next step S005 together with the distance Ln.

Next, in step S005, the preceding vehicle is driven.
Radius of curvature R of the locus_estCalculated distance from current position of
The curvature radius data of the lane of the host vehicle closest to Ln
R _DATAIs read out and the radius of curvature of the traveling path of the preceding vehicle
R_estIs calculated. Then in step S006
These differences are compared. If there are N preceding vehicles, compare N
To do. Next, in step S007, the curvature of the lane of the host vehicle
Radius data R_DATAThe running gauge of the preceding vehicle that has the smallest difference with
Radius of curvature R_estThe preceding vehicle N having
Difference DN is a predetermined value D_DATAIt is determined whether or not it falls below.
The difference DN is a predetermined value D_DATAIf not less than
It is determined that there is no preceding vehicle traveling on one lane.
The difference DN is a predetermined value D_DATAIf less than the preceding vehicle N
Is the preceding vehicle traveling in the same lane as the host vehicle.
Is determined.

In the present embodiment, the preceding vehicle determination device is constructed by comparing the radii of curvature, but the preceding vehicle determination device is also constructed by comparison by the reciprocal curvatures of the radii of curvature or functions thereof. Is the invention of.
Further, regarding the radius of curvature or the curvature, the counterclockwise direction in the traveling direction of the host vehicle is processed as a positive value and the clockwise direction as a negative value, but the positive and negative values may be reversed or only the absolute value may be used.

[Second Embodiment] Next, FIG. 15 shows the operation of the preceding vehicle determining apparatus according to the second embodiment of the present invention. Figure 15
FIG. 9 is a conceptual diagram showing a relationship between a predetermined point and a travel history of a preceding vehicle when a road curve is moved along with a change in the vehicle direction by the preceding vehicle determination device according to the second embodiment.
In FIG. 3, the problem of the conventional preceding vehicle determination is shown, but in the present embodiment, even if the direction of the own vehicle deviates from the road direction, it matches with the direction of the own vehicle. The preceding vehicle is determined by using the road shape.

In FIG. 15, an origin O _map , a map coordinate system (fixed coordinate system) based on two orthogonal axes X _map and Y _map ,
The vehicle position P _i existing thereabove at time i, the road coordinates R _i , R _{i + 1} , R _{i + 2} , R _{i + 3} , R _{i + 4} and R _{i + 5} , and the resulting road curve C ₀ , positions A ₁ , A ₂ , A _{3 of} the preceding vehicle A, and positions B ₁ , B ₂ , B ₃ of the preceding vehicle B are shown. Road coordinates R _i , R _{i + 1} ,
R _{i + 2} , R _{i + 3} , R _{i + 4} and R _{i + 5} , and thus the road curve C
Is a road curve is calculated road coordinate is obtained and thereby against the vehicle position P _i at time i. Also,
Positions A ₁ , A ₂ , A _{3 of} the preceding vehicle A, Positions B ₁ , B of the preceding vehicle B
_2, B ₃ is the position coordinates of the vehicle position P _i of the two stored to date with respect to the preceding vehicle A, 3 one time point for B at time i. For example, at time i, two preceding vehicles A and B are present at position A ₃ and position B ₃ , respectively.
₁ , A ₂ , positions B ₁ and B ₂ are past trajectories. The coordinates in the map coordinate system (fixed coordinate system) are indicated by (x, y). Hereinafter, all are considered at time i.

Now, as shown in FIG. 15, consider the own vehicle coordinate system (moving coordinate system) from the own vehicle position P _i and the direction of the own vehicle. First, the vehicle position P _i (the coordinates of the fixed coordinate system are (x _p ,
y _p )) as the origin, and the vehicle traveling direction at time i is the P ₀ axis, and the Q ₀ axis is perpendicular to it. Thus, the coordinates in the own vehicle coordinate system (moving coordinate system) are indicated by (p, q).
Further, the angle φ own vehicle coordinate system (angle φ moving coordinate system) rotated by the angle φ from the traveling direction of the own vehicle at the time i is similarly considered. That is, the vehicle position P _i (coordinates of the fixed coordinate system
(x _p , y _p )) as an origin, and the Pφ axis rotated by an angle φ (counterclockwise is positive) from the traveling direction of the vehicle at time i,
The Qφ axis is taken perpendicular to it. Thus, the coordinates of the angle φ own vehicle coordinate system (angle φ moving coordinate system) are indicated by (pφ, qφ).

Next, a curve obtained by rotating the road curve C ₀ in the own vehicle coordinate system (moving coordinate system) by an angle φ around the own vehicle position P _i is defined as Cφ. The function q = f (p) in the own vehicle coordinate system (moving coordinate system) of the road curve C is the angle φ of the curve Cφ obtained by rotating the road curve C as it is by the angle φ of the own vehicle coordinate system (angle φ moving coordinate system). It can be used as a function qφ = f (pφ).

Based on these preparations, the operation of the second embodiment will be shown. In this embodiment, it is determined at each time i whether or not the preceding vehicle is the preceding vehicle in the same lane by the following calculation. First, for each angle φ (eg φ = wφ _th , w = 0, ±
1, ± 2, ..., ± W), on the angle φ own vehicle coordinate system (angle φ moving coordinate system), the curve Cφ and the position of each preceding vehicle, that is, the positions A ₁ , A _{2 of} the preceding vehicle A, A ₃ , the position B ₁ of the preceding vehicle B,
The distance from B ₂ and B ₃ is calculated. This is performed for all the set angles φ, the preceding vehicle having the smallest sum of the distances to the curve Cφ and the angle φ at that time are determined, and the preceding vehicle is the preceding vehicle in the same lane as the own vehicle. It is a judgment.

From the coordinates (x, y) of the map coordinate system (fixed coordinate system) to the coordinates (p, q) of the own vehicle coordinate system (moving coordinate system) and the angle φ.
The transformation of the own vehicle coordinate system (angle φ moving coordinate system) to the coordinates (pφ, qφ) is general rotation and equilibrium movement. Map coordinate system vehicle coordinate system from the axis X _map (fixed coordinate system) a rotation angle of the P ₀ axis (the moving coordinate system) theta as (counterclockwise positive), pφ = xcos (θ + φ) - ysin (θ + φ) -x _p and qφ = x sin (θ + φ) + y cos (θ + φ) -y _p . In the following, the own vehicle coordinate system (moving coordinate system) is treated as the angle φ own vehicle coordinate system (angle φ moving coordinate system) when the angle φ = 0.

The curve Cφ on the angle φ own vehicle coordinate system (angle φ moving coordinate system) is particularly simple when the curve Cφ is represented by a small arc and a straight line connection. That is, the road curve C may be obtained in the map coordinate system (fixed coordinate system), the center may be converted as described above, and the radius may be used as it is. Converting straight lines is also very easy.

Angle φ own vehicle coordinate system (angle φ moving coordinate system)
The distance between the above curve Cφ and the point of coordinates (pφ, qφ) can be easily obtained as follows. The distance to the arc portion of the curve Cφ is the distance between the center of the arc and the point of coordinates (pφ, qφ),
It is the difference from the radius of the arc. In addition, for example, on the angle φ own vehicle coordinate system (angle φ moving coordinate system), the distance between the point of the line (q = ap + b) and the coordinate (pφ, qφ) is | apφ-qφ + b |
/ (A ² +1) ^1/2 .

This content is shown in the flowchart of FIG. It is assumed that each of the N preceding vehicles has a vehicle number of j (j is a natural number of 1 or more and N or less). First, step 001 (abbreviated as S001 in FIG. 16).
The same applies hereinafter. ), The time i is recognized. Next, in step 002, the position P _{i of} the vehicle and m positions of obstacles such as N preceding vehicles are acquired. Then step 00
3, the angle φ, the determination result angle Φ, the determination result preceding vehicle number J, and the minimum difference E _min are initialized. The minimum value φ _min is set as the initial value of the angle φ. For example, the angle φ is wφ
_th , but w = 0, ± 1, ± 2,…, ± W, and −Wφ _th to Wφ
_The minimum value φ _min = -W φ if it is swung up to _{th in} φ _th increments
_th (<0). The initial value of the determination result angle Φ is set to 0. As a result of the determination, the initial value of the preceding vehicle number J is set to 0. As the initial value of the minimum difference E _min , E _{t h} (> 0) is set. Next, in step 004, the road data is grasped as a curve Cφ on the angle φ own vehicle coordinate system (angle φ moving coordinate system). For example, it is a function of the coordinates (pφ, qφ) on the curve Cφ, or for the part of the arc by the connection of the arc and the straight line the center and radius.

Next, at step 005, 1 is set as the initial value of the vehicle number j. Next, in step 006, the m position coordinates of the vehicle number j are converted into the angle φ own vehicle coordinate system (angle φ
Convert to coordinates in the moving coordinate system).

Next, at step 007, on the angle φ own vehicle coordinate system (angle φ moving coordinate system), the curve Cφ and the vehicle number j
The average of the sum of distances Eφ _j is obtained from the m position coordinates of. Next, at step 008, it is determined whether the average Eφ _j of the sums of the distances at the positions of the vehicle number j is equal to or larger than the minimum difference E _min . If the average Eφ _j of the sums of the distances of the vehicle numbers j is equal to or more than the minimum difference E _min , step 0
09, and the average E of the sum of the distances at the position of the vehicle number j concerned
If φ _j is less than the minimum difference E _min , the process proceeds to step 010. In step 010, the minimum difference E _min is replaced with the average Eφ _j of the sum of the distances of the vehicle number j, the determination result preceding vehicle number J is replaced with the vehicle number j, and the determination result angle Φ is the angle φ. After the replacement, proceed to step 009.

In step 009, it is determined whether the vehicle number j is equal to the maximum value N. If the vehicle number j is equal to the maximum value N, the process proceeds to step 011. If the vehicle number j is not equal to the maximum value N (if the vehicle number j is smaller than the maximum value N), the process proceeds to step 012. In step 012, the vehicle number j is replaced with j + 1 and the process returns to step 006.

At step 011 the angle φ is the maximum value φ.
_maxIt is determined whether or not the above. Where φ_maxIs for example
The angle φ is wφ_th, Where w = 0, ± 1, ± 2,…, ± W,
-Wφ _thTo Wφ_thUp to φ_thMaximum if shaken in steps
Value φ_max= Wφ_th(> 0). Angle φ is maximum φ_max
If so, the process proceeds to step 013 and the angle φ is the maximum value φ.
_maxIf smaller, go to step 014. Step 0
In 14, the angle φ is φ + φ_thReplace with step 00
Return to 5.

In snap 013, the judgment result vehicle number J
Is equal to 0. If the judgment result vehicle number J is equal to 0, the routine proceeds to step 015, where it is judged that there is no preceding vehicle. If the determination result vehicle number J is not equal to 0, the process proceeds to step 016, and it is determined that there is a preceding vehicle corresponding to the determination result vehicle number J. After that, the process may loop back to START, or other process may be performed, a display to the driver, etc. may be performed based on the determination results of steps 015 and 016 before looping.

[Brief description of drawings]

FIG. 1 is a block diagram showing the configuration of a preceding vehicle determination apparatus that is a specific first embodiment of the present invention.

FIG. 2 is a conceptual diagram showing a conventional problem of determining a preceding vehicle based on a steering angle.

FIG. 3 is a conceptual diagram showing a problem of a preceding vehicle determination based on a conventional absolute comparison with a road shape.

FIG. 4 is a conceptual diagram showing determination of a preceding vehicle by relative comparison with a road shape according to the present invention.

FIG. 5 is an explanatory diagram of a road map in the case where the data of the radius of curvature at each position of the road is included.

FIG. 6 is a block diagram showing a configuration example of a road curvature radius acquisition means.

FIG. 7 is an explanatory diagram of a road curvature radius acquisition means of FIG.

FIG. 8 is an explanatory diagram of a road map when only the coordinates at each position of the road are included.

FIG. 9 is a block diagram showing another configuration example of the road curvature radius acquisition means.

FIG. 10 is an explanatory diagram for obtaining a radius of curvature by arc fitting.

FIG. 11 is an explanatory diagram of a case where a radius of curvature is obtained by using a spline curve.

FIG. 12 is an explanatory diagram of a traveling history of processing contents of a preceding vehicle determination unit 300.

FIG. 13 is an explanatory diagram comparing the radius of curvature of the traveling locus of the preceding vehicle with the radius of curvature of the road.

FIG. 14 is a flowchart showing an outline of the processing contents of a preceding vehicle determination means 300.

FIG. 15 is a concept showing a relationship between a preceding vehicle and a running history of a predetermined number of points when a road curve is moved along with a change in the direction of the own vehicle by the preceding vehicle determination device according to the second specific embodiment of the present invention. Fig.

FIG. 16 is a flowchart showing an outline of processing contents in the second embodiment.

[Explanation of Codes] 100 Forward Obstacle Detecting Unit 101 Radar Device 102 Radar Signal Processing Device 200 Own Vehicle Position Obtaining Unit 201 GPS Device 202 Own Vehicle Position Estimating Means 203, 2031, 2032 Road Map Data 210, 210a, 210b Road Curvature Radius Acquisition means 211 Corresponding position extraction means on map 212 Curvature radius data extraction means 213 Peripheral shape data extraction means 214 Curvature radius calculation means 300 Preceding vehicle determination means 301 Travel history storage means 302 Preceding vehicle traveling locus curvature radius estimation means 303 Shape comparison means P of the own vehicle position L _Ai preceding vehicle a at _i time i, the distance phi _Ai preceding vehicle a at time i with respect to the vehicle, from the direction SL ₁ at time i from the first lane SL ₂ to CL ₁ to CL ₂ with respect to the vehicle the first record was mistaken 'from ₁ CL' second lane SL up to ₁ The second lane was mistaken 'from ₂ CL' emissions SL up to ₂

   ─────────────────────────────────────────────────── ─── Continued front page    F-term (reference) 5H180 AA01 CC12 CC14 LL01 LL04                 5J070 AC02 AC13 AE01 AF03 AK22                       BF19

Claims (7)

[Claims] 1. A preceding vehicle determination device that is mounted on a vehicle and determines whether a preceding vehicle ahead is traveling in the same lane as the vehicle is currently traveling while traveling on a road with a plurality of lanes. By searching and checking the distance from the vehicle to the obstacle when there is an obstacle, the forward obstacle detection means that detects the direction from the vehicle, and the road map data, the vehicle's Own vehicle position acquisition means for detecting the position, road curvature radius acquisition means for acquiring the radius of curvature of the road from the road map data, and distance from the own vehicle of the preceding vehicle ahead detected by the front obstacle detection means A traveling history of the preceding vehicle obtained from the direction from the own vehicle and the position of the own vehicle obtained by the own vehicle position obtaining means, and the traveling history of the preceding vehicle output by the road curvature radius obtaining means And a radius of curvature of the corresponding positions road, the preceding vehicle is the preceding vehicle determination apparatus characterized by having a determining preceding vehicle judgment means whether traveling lane same lane which the vehicle is currently traveling. 2. The preceding vehicle determination means is obtained by the distance of the preceding vehicle ahead detected by the front obstacle detection means from the own vehicle, the direction from the own vehicle, and the own vehicle position acquisition means. A traveling history storing means for storing the position of the own vehicle, a preceding vehicle traveling locus curvature radius estimating means for estimating a curvature radius of the traveling locus of the preceding vehicle from the data of the traveling history storing means, and the road curvature radius obtaining means. 2. The preceding vehicle determination device according to claim 1, further comprising shape comparison means for comparing the radius of curvature of the preceding vehicle with the radius of curvature of the preceding vehicle traveling locus curvature radius estimation means. 3. The preceding vehicle determination device according to claim 1, wherein the road map data includes curvature radius data. 4. The curvature radius data included in the road map data includes a plurality of curvature radius data at a connecting portion between roads such as intersections where curvatures are discontinuous, and the curvature radius data. The preceding vehicle determination device according to claim 3, wherein the relative shape of the road can be reproduced as a whole. 5. The preceding vehicle determination device according to claim 1, wherein the road map data does not have curvature radius data, and the curvature radius of the road is calculated from the road shape. 6. A preceding vehicle determination device which is mounted on a vehicle and determines whether a preceding vehicle ahead is traveling in the same lane as the vehicle is currently traveling while traveling on a road having a plurality of lanes. By searching and checking the distance from the vehicle to the obstacle when there is an obstacle, the forward obstacle detection means that detects the direction from the vehicle, and the road map data, the vehicle's Own vehicle position acquisition means for detecting the position, distance from the own vehicle of the preceding vehicle ahead detected by the front obstacle detection means, direction from the own vehicle, and obtained by the own vehicle position acquisition means A travel history acquisition unit that obtains a travel history of a predetermined number of preceding vehicles from the position of the own vehicle; a road curve calculation unit that sets a coordinate system and calculates a curve indicating the shape of the traveling road on the coordinates. car Converts the traveling history of a predetermined number of preceding vehicles in the case where the direction is changed to the coordinate system, and minimizes the distance from the curve showing the shape of the traveling road fixed on the coordinate system. Preceding vehicle determination means that determines the preceding vehicle and the direction of the own vehicle, and determines that the preceding vehicle is traveling in the same lane as the own vehicle is currently traveling if the distance is equal to or less than a predetermined value under the conditions. A preceding vehicle determination device having: 7. The preceding vehicle determination device according to claim 6, wherein the road curve calculation means calculates an arc indicating the shape of the traveling road.