JPH07306996A - Estimating device for traveling course for automobile - Google Patents

Abstract

PURPOSE:To accurately estimate the traveling course even at the time of changing traffic lanes. CONSTITUTION:With a traffic lane changing means 29a, the estimated value on the white lines to the right and left by a traveling course estimating means 6C is detected to be different from the estimated value by a traveling road estimating means 6B and the change of the traffic lane is judged based on the uncoincidence of the estimated value. The uncoincident estimated value is continued for the constant time and the estimated value by the means 6B becomes gradually low, the change of the traffic lane is judged. At the time of changing the traffic lane, the estimated value by the means 6B based on the car state amount is used to the prescribed distance in front of the vehicle. When it is over, the estimated value by the means 6C is used based on the image processing. Then, the traveling course is estimated by a traveling area estimating means 29.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a travel route estimating device for a vehicle for estimating a travel route where a vehicle is expected to travel in the future.

[0002]

2. Description of the Related Art Conventionally, information obtained by scanning a wide range of a radar device is provided with a traveling road estimating means for estimating a traveling road on which the own vehicle is predicted to travel from the traveling state such as the steering angle and the vehicle speed of the own vehicle. Among them, there is known one that picks up only the one in the region along the traveling road predicted by the traveling road estimating means and judges the possibility that the own vehicle and the obstacle come into contact with each other.

As a means for estimating such a traveling road, as described in, for example, Japanese Patent Laid-Open No. 4-137014, image information input from a video camera or the like is used.
It is known that luminance information and dispersion information are extracted, and a white line on the traveling road is detected based on the information to estimate the traveling road. Further, as described in, for example, Japanese Patent Publication No. 51-7892, there is also known one which estimates a traveling road (running road) based on vehicle state quantities such as a steering angle, a vehicle speed and a yaw rate.

In the case of image processing, usually,
Since the white lines drawn at the left and right ends of the road will be detected and the road edges will be recognized, the range of the road that can be estimated is wide, and there is a possibility that the vehicle will come into contact with the vehicle as described above rather than due to the vehicle state quantity This is advantageous for setting an area for detecting an obstacle.

[0005]

However, when such an image processing is used, it cannot be applied as it is when changing lanes.

[0006] The present invention provides a traveling road estimating device for an automobile, which can accurately estimate the traveling road even when the lane is changed.

[0007]

SUMMARY OF THE INVENTION The present invention provides a traveling road estimating device having a traveling road estimating means for detecting a white line on a road surface based on image processing and estimating a traveling road on which the vehicle is expected to travel in the future. It is a prerequisite.

According to a first aspect of the present invention, a traveling road estimating means for estimating a traveling road on which the vehicle is expected to travel in the future based on the vehicle state quantity, and an output from the traveling road estimating means and the traveling road estimating means are received. Lane change determining means that detects that the estimated values of the left and right white lines by the traveling road estimating means are different from the estimated values by the traveling road estimating means, and determines the lane change based on the yaw rate and the steering angle when the estimated values do not match. And a configuration including.

According to the second aspect of the present invention, the lane change determining means determines that the lane is changed when the estimated value of the disagreement continues for a certain period of time and the estimated value of the traveling path estimating means gradually decreases. It is a judgment.

In the third aspect of the present invention, the lane change determining means determines that the lane is changing when the immediately preceding estimated values are equal and the estimated values by the traveling path estimating means have changed.

According to the invention of claim 4, further, the output from the lane change judging means is used, and when the lane is changed, the estimated value by the traveling road estimating means is used up to a predetermined distance in front of the vehicle. The travel route estimating apparatus according to claim 1, 2, or 3, further comprising a travel area estimating unit that uses the estimated value.

[0012]

According to the first aspect of the present invention, the lane changing means detects that the estimated values for the left and right white lines by the traveling road estimating means are different from the estimated values by the traveling road estimating means, and when the estimated values do not match. The lane change is determined based on the yaw rate and the steering angle.

According to the second aspect of the present invention, when the estimated value of the disagreement continues for a certain period of time and the estimated value by the traveling path estimating means gradually decreases, the lane change is determined by the lane change determining means. Is judged.

According to the third aspect of the present invention, the lane change determining means determines that the lane is changing when the immediately preceding estimated values are equal and the estimated values by the traveling path estimating means have changed.

According to the invention of claim 4, when changing lanes,
The travel area estimation means estimates the travel path by using the estimated value by the travel path estimation means up to a predetermined distance in front of the vehicle, and by using the estimated value by the travel path estimation means.

[0016]

Embodiments of the present invention will be described below with reference to the drawings. This example is an example in which the vehicle travel path estimation device according to the present invention is applied to an obstacle detection device.

Embodiment 1 In FIG. 1 showing the whole automobile, reference numeral 1 is an automobile, and a distance sensor 3 is provided at a front portion of a vehicle body 2. The distance sensor 3 measures the distance to an obstacle on the road, and emits pulsed laser light as a radar wave toward the front of the host vehicle from the transmitter and at the same time as a preceding vehicle in front of the host vehicle. The radar head unit is configured to receive a reflected wave reflected by an obstacle at a receiver. Further, the distance sensor 3 emits pulse laser light (beam) emitted from its emission portion, which is thin in the vertical direction and spread in a fan shape in the vertical direction.
Is a scan type that scans a horizontal direction at a relatively wide angle.

Reference numeral 4 denotes a CCD camera arranged in the upper part of the passenger compartment for photographing the scene in front of the vehicle (running path) within a predetermined range. The scene in front of the vehicle photographed by the camera 4 is: The image is input to the image processing unit 5 and subjected to image processing, and the control unit 6 estimates the travel route based on the white line of the road.

Further, the control unit 6 has a structure shown in FIG.
In addition to the signal from the CCD camera 4, a vehicle speed sensor 7 for detecting the vehicle speed of the vehicle, a steering angle sensor 8 for detecting the steering angle of the steering wheel 8a, and The signal from the yaw rate sensor 9 that detects the yaw rate generated by the vehicle is also input,
Based on these signals, the road condition is displayed on the head-up display 10, and when an obstacle in front of the vehicle is detected, the alarm means 11 is activated and the vehicle control device 1 is activated.
2 operates the brake 12a to automatically apply a braking force to each wheel 13, ....

Specifically, as shown in FIG. 3, the signal from the distance sensor 3 is input to the calculation unit 22 through the signal processing unit 21 of the control unit 6, and the calculation unit 22 emits the laser reception light. The distance between each obstacle existing in the scanning range and the own vehicle due to the delay time from the time point,
It is configured to calculate the relative speed and the direction of the obstacle with respect to the own vehicle.

The signal processing section 21 and the computing section 23 constitute an obstacle detecting means 6A for detecting an obstacle existing in a predetermined area in front of the own vehicle.

The detection signals of the sensors 7, 8 and 9 are input to a traveling road estimating means 6B which estimates a traveling road (specifically, its radius of curvature) based on vehicle state quantities such as a steering angle, a vehicle speed and a yaw rate. The first traveling path estimating means 23 of the traveling path estimating means 6B estimates a predicted traveling path on which the vehicle will travel in the future from the steering steering angle and the vehicle speed of the vehicle, while the second traveling path means 24 is the steering angle of the vehicle,
From the vehicle speed and the yaw rate, it is designed to estimate the expected traveling route of the vehicle.

The signal from the image processing unit 5 is
The left and right white line estimating means 25 and the right and left white line estimating means 26, which extract the left and right white lines of the road (running road) on which the vehicle is traveling from the scene in front of the own vehicle and estimate the left and right white lines, are input to the left white line and the right white line, respectively. White lines (specifically their radii of curvature) are estimated.

The left white line and right white line estimating means 25, 26 constitute a traveling road estimating means 6C for estimating a traveling road based on image processing. When estimating the white line, each of the estimating means 25 and 26 of the traveling road estimating means 6C, if necessary,
In addition to the white line candidate points from the image processing unit 5, the left and right white lines are estimated based on at least two virtual white line candidate points initially set for one white line behind the vehicle. .

Then, the traveling area estimating means 29 receives the outputs of the traveling road estimating means 6B and the traveling road estimating means 6C, and in the traveling area estimating means 29, the traveling area (corresponding to an obstacle judging area for making an obstacle judgment). ) Is set. At the time of estimating the traveling area, the estimated values of the left and right white lines by the traveling road estimating means 6C, that is, the curvature radii RL and RR about the white lines, and the estimated values of the traveling road by the traveling road estimating means, that is, the curvature radius R11 of the traveling road. Lane change determining means 2 determines whether the lane change is based on the yaw rate and the steering angle when the estimated values do not match.
9a.

Further, the obstacle information from the arithmetic unit 22 and the obstacle judgment area information from the traveling area setting means are input to the obstacle judgment means 30, and in the obstacle judgment means 30, the distance sensor 3 detects them. The need to avoid obstacles
If obstacle judgment is performed in the obstacle judgment area set by the traveling area setting means 29 and it is judged that it is necessary to avoid the obstacle, it is displayed on the head-up display 10 and an alarm is issued by the alarm device 11. After that, the brake device 12a of the vehicle control device 12 is automatically operated.

-Basic Control for Obstacle Detection by Obstacle Detection Device-Hereinafter, basic control for obstacle detection by the obstacle detection device using the traveling path estimation device will be described.

In FIG. 4, when starting, first, in step S1, the traveling route estimating means 6B estimates the traveling route, and in step S2, the left white line and right white line estimating means 25, 26 by image processing are performed. The left and right white lines are estimated, and the traveling path is estimated based on the left and right white lines.
Then, in step S3, the front of the vehicle is recognized by the distance sensor 3 and an obstacle (obstacle information) estimated to be an obstacle is detected.

Subsequently, in step S4, the first traveling area in which it is necessary to detect an obstacle based on the traveling route estimated in step S1 is set, and the second traveling region is estimated based on the traveling route estimated in step S2. Regions are set, and the traveling region setting means 29 is based on both traveling regions.
Thus, an obstacle determination area (running area) for determining whether or not it becomes an obstacle is determined.

Then, in step S5, obstacle information is masked based on the obstacle judgment area, and in step S6, obstacle judgment is performed. The obstacle determining means 30 executes the above steps S4 to S6.

Then, in step S7, obstacle avoidance control is performed if necessary, and the process returns. Obstacle avoidance control
For example, although the warning is given by the warning device 11 and the brake 12a of the vehicle control device 12, although not specifically shown, it may be given by an automatic steering device or the like.

-Traveling Road Estimation Control by Traveling Road Estimating Means 6B-The estimation of the traveling road in step S1 is performed according to the subroutine shown in FIG. That is, in step S11, the signals from the steering angle sensor 5, the vehicle speed sensor 6, and the yaw rate sensor 7 are read, and then, in step S12, the first prediction method based on the steering steering angle θH and the vehicle speed V0 Predict the path of travel. Specifically, the estimated value of the traveling road, that is, the radius of curvature R11 of the traveling road and the side slip angle β of the vehicle
11 is calculated by the following formula.

[0033]

[Equation 1] Then, in step S13, the traveling path of the host vehicle is predicted by the second prediction method based on the yaw rate γ and the vehicle speed V0. Specifically, the estimated value for the traveling road, that is, the radius of curvature R12 of the traveling road and the side slip angle β12 of the vehicle are calculated by the following formulas.

[0034]

[Equation 2] Then, in step S14, it is determined whether or not the absolute value of the steering angle θH is smaller than the predetermined angle θc. If this determination is YES, the traveling path predicted by the second prediction method is selected in step S16, and the curvature radius R of the traveling path is selected.
The estimated value R12 is set to 1 and the vehicle side slip angle β
Set the estimated value β12 to 1 and return.

On the other hand, when the determination in step S14 is NO, that is, when the steering steering angle θH is larger than the predetermined angle θc, the absolute value of the estimated value R11 for the traveling path predicted by the first prediction method is further calculated in step S15. The value is compared with the absolute value of the estimated value R12 for the traveling path predicted by the second prediction method. When the estimated value R11 for the traveling road predicted by the first prediction method is smaller, the process proceeds to step S17, the estimated value R11 is set to the curvature radius R1 of the traveling road, and the side slip angle of the vehicle is set. While the estimated value β11 is set to β1, when the estimated value R12 for the traveling path predicted by the second prediction method is smaller, the process proceeds to step S16, and the estimated value R12 is set to the radius of curvature R1 of the traveling path. At the same time as setting, the estimated value β12 is set for the vehicle side slip angle β. That is, the smaller radius of curvature is selected as the traveling path.

Further, the traveling route estimating means 6B performs both the estimation of the traveling route based on the steering angle θH and the vehicle speed V0 and the estimation of the traveling route based on the yaw rate γ and the vehicle speed V0 to determine the own vehicle. Since either one of the estimations is used according to the traveling state, it is possible to appropriately perform the traveling path estimation. That is, when the host vehicle turns on a curved road having a cant, the host vehicle makes a turning motion by the cant even if the steering wheel is not steered greatly. The estimated value R12 becomes smaller than the estimated value R11 for the traveling path predicted based on the steering angle θH. At this time, the traveling path estimating unit 6B determines the yaw rate γ.
Since the estimated value R12 for the traveling route predicted based on is used, the traveling route can be appropriately estimated without being influenced by the cant. Further, when the host vehicle makes a sharp turn, the traveling road estimating means 6B causes the traveling road to have a radius of curvature R corresponding to the steering steering angle θH having a large value.
It is estimated that the number is 11 small, and it is possible to appropriately estimate the traveling path even in a sudden turning operation.

-Basic control of traveling road estimation by the left and right white line estimating means- The estimation of the traveling road in the step S2 is performed by the left and right white line estimating means 25, 26 according to the subroutine shown in FIG. As preconditions, it is considered that a side slip angle does not occur on a straight road, a body posture angle with respect to a white line is small on a straight road, and a traveling locus is a parallel movement of the lane on a curved road. The coordinates are assumed to have the vehicle on the road surface as the origin, the longitudinal direction of the vehicle as the y-axis, and the lateral direction as the x-axis.

Specifically, in FIG. 6, when starting, image data is first captured (step S21),
A threshold for binarization is set (step S22), and then binarization processing of 1 or 0 is performed depending on whether or not the brightness of each pixel exceeds the threshold (step S23).

Then, the left and right scan windows are set so as to correspond to the left and right white lines (step S24),
Subsequently, the scan pitch in the front-rear direction of the automobile is set (step S25), the scan window is scanned in accordance with the scan pitch, and the white line candidate points (that is, the points which are set to 1 by the binarization processing) are detected (step S26). ), And is converted into plane coordinates by inverse perspective transformation (step S27).

Then, the virtual candidate points are added to the white line candidate points to estimate the travel route based on the left and right white lines, and the obstacle determination area is set based on the travel route (step S28).
To return.

The obstacle determination area is set by using an approximate curve (y = ax ² + bx + c) by the method of least squares for the left and right white lines using the white line candidate points and the virtual candidate points, specifically, a quadratic curve for the left white line. AL, bL, cL, and the quadratic curve coefficients aR, bR, cR for the right white line are calculated. In order to detect an obstacle on the road, the quadratic curve (y = ax
² + bx + c) and the coefficients aL, aR
Is the radius of curvature of the quadratic approximation curve, RL (RR)
a = 1 / 2RL (1 / 2RR) and the coefficients bL, bR
Is the body posture angle or sideslip angle with respect to the white line, and the coefficient c
L and cR represent the lateral deviation amount from the vehicle center to the white line.

Next, the control for estimating the traveling path when the lane is changed will be described.

In FIG. 7, when starting, it is first judged whether or not the estimated values RL and RR are equal and they are not equal to the estimated value R1 (step S31), and Y
If ES, the process proceeds to step S32. On the other hand, if NO, the lane change is not in effect, and therefore the process directly returns.

In step S32, the immediately preceding estimated values RL, R
It is determined whether or not R and R1 are substantially equal, and if they are equal, it is possible to change the lane. Therefore, it is determined whether or not the yaw rate and the steering angle have changed (step S33). It is determined that the lane has been changed (step S34), and the process directly returns. Therefore, it is considered that the driver's attention is sufficiently drawn when the lane is changed, and therefore the obstacle judgment is not performed.

On the other hand, if the immediately preceding estimated values RL, RR, and R1 are not substantially equal and the yaw rate and the steering angle have not changed, it is determined that the lane is not changed. Using RL and RR (step S35), the road is estimated and the process returns.

In addition, control when changing lanes can be performed as follows.

Embodiment 2 As shown in FIG. 8, when starting, whether the estimated values RL and RR by the traveling road estimating means 6C are equal and are not equal to the estimated value R1 by the traveling road estimating means B. Whether or not it is determined (step S41). If YES, the process proceeds to step S42, while if NO, the process directly returns.

In step S42, it is determined whether or not the lane is changed based on changes in the yaw rate and the steering angle. If the lane is changed, it is estimated about 5 m based on the estimated value R1 for the traveling road, and thereafter. Based on the estimated value RR for the right white line, the road is estimated to the right, that is, to the side where the lane is changed (step S43), and while the process returns, if the lane is not changed, the left and right white lines are estimated by the road estimation means 9C. Using the values RL and RR (step S44), the road is estimated and the process returns.

Therefore, the road can be estimated even when the lane is changed.

Embodiment 3 In FIG. 9, when starting, the estimated values (curvature radii of white lines) RL and RR for the white lines on the left and right of the traveling road by the traveling road estimating means 6C are equal, and they are the traveling road estimating means 6B. It is determined whether or not the state is not equal to the estimated value (curvature radius of the traveling road) R1 of the traveling road according to (step S51). If YES, there is a possibility of changing lanes, so the process proceeds to step S52. On the other hand, if NO, it is considered that the lane has not been changed, and the process directly returns.

In step S52, it is determined whether or not this state continues for a certain period of time or more. If it continues, it is determined that the steering angle is not the lane change but the steering angle deviation (step S53). Is corrected (step S5
Four).

In this case, the steering angle is corrected by the estimated value RL (= R
R) and the steering angle θ1 obtained from the steering angle sensor 8
Calculate the difference Δ from 2 and use it as the steering angle correction amount.

On the other hand, if it has not continued for a certain period of time,
It is determined whether or not the estimated value R1 for the traveling road is gradually decreasing (step S55). If YES, it is determined that the lane is changed (step S56), and the estimated value R1 for the traveling road is used ( Step S57), and returns.

Therefore, in this case, the traveling route estimating means 6B
The traveling area is estimated by the traveling area estimating means 29 based on the estimated value R1 according to However, since it is a lane change, there is no possibility of traveling ahead of the vehicle V1 that is a predetermined distance or more, so that the tip portion of the estimated traveling area A is cut as shown in FIG. B1 and B2 are driving routes before and after the lane change, respectively.

Further, unless it is gradually decreased, it is considered that the lane is not changed. Therefore, the estimated values RL and RR by the traveling road estimating means 6C which are advantageous in traveling road estimation.
Is used (step S58), and the process returns.

[0056]

According to the first aspect of the present invention, the lane change means detects that the estimated values for the left and right white lines by the traveling road estimating means are different from the estimated values by the traveling road estimating means, and when the estimated values do not match. Since the lane change is determined based on the yaw rate and the steering angle, it is possible to estimate the traveling path in consideration of the lane change.

According to the second aspect of the present invention, it is determined that the lane is changed when the estimated value of the disagreement continues for a certain period of time and the estimated value by the traveling route estimating means gradually decreases. You can judge the lane change.

According to the third aspect of the present invention, when the estimated values immediately before are equal and the estimated values by the traveling route estimating means change, it is determined that the lane is changed, so that the malfunction is prevented when the lane is changed. It is possible to cope with the deviation of the steering angle.

According to the invention of claim 4, when the lane is changed,
When the lane is changed, the estimated value by the traveling road estimating means is used up to a predetermined distance in front of the vehicle, and when the traveling distance is exceeded, the estimated value by the traveling road estimating means is used to estimate the traveling road by the traveling area estimating means. Also, it becomes possible to estimate the traveling path.

[Brief description of drawings]

FIG. 1 is a perspective view of an automobile.

FIG. 2 is a block diagram of a control system.

FIG. 3 is a block diagram of a control unit.

FIG. 4 is a flowchart showing a flow of an obstacle detection process.

FIG. 5 is a flow chart showing a subroutine of travel route estimation.

FIG. 6 is a flowchart showing a subroutine of travel route estimation.

FIG. 7 is a flowchart showing a subroutine for estimating a traveling path.

FIG. 8 is a flow chart showing a subroutine for estimating a traveling path.

FIG. 9 is a flowchart showing a subroutine of travel route estimation.

FIG. 10 is an explanatory diagram of travel path estimation.

[Explanation of symbols]

 1 Car 6 Control Unit 6A Obstacle Detecting Means 6B Traveling Road Estimating Means 6C Traveling Road Estimating Means 7 Vehicle Speed Sensor 8 Steering Angle Sensor 9 Yaw Rate Sensor 29 Traveling Area Setting Means 29a Lane Change Judging Means

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Tomohiko Adachi No. 3 Shinchi, Fuchu-cho, Aki-gun, Hiroshima Prefecture Mazda Co., Ltd. (72) Inventor Hiroshi Nakaue No. 3 Shinchi, Fuchu-cho, Aki-gun, Hiroshima Mazda Stock In the company

Claims (4)

[Claims] 1. A traveling road estimating device having a traveling road estimating means for detecting a white line on a road surface based on image processing and estimating a traveling road which is expected to travel in the future. Received from the traveling road estimating means for estimating the traveling road expected to travel in the future and the traveling road estimating means and the traveling road estimating means, the estimated values for the left and right white lines by the traveling road estimating means are estimated as the traveling road. And a lane change judging means for judging a lane change based on a yaw rate and a steering angle when the estimated values do not match each other. 2. The lane change determining means determines that the lane is changing when the estimated value of the disagreement continues for a certain period of time and the estimated value by the traveling path estimating means gradually decreases. The traveling path estimation device according to claim 1. 3. The traveling according to claim 1, wherein the lane change judging means judges that the lane change is made when the immediately preceding estimated values are equal and the estimated values by the traveling road estimating means have changed. Road estimation device. 4. A travel area estimating means that receives the output of the lane change determining means, uses the estimated value of the traveling road estimating means up to a predetermined distance in front of the vehicle when changing the lane, and uses the estimated value of the traveling road estimating means if the estimated value is exceeded. The traveling path estimation device according to claim 1, claim 2, or claim 3, which further comprises: