JPH09263200A - Alarm device for vehicle - Google Patents

Abstract

PROBLEM TO BE SOLVED: To appropriately generated an alarm while predicting the possibility of deviation from the traffic lane due to overspeed before going in a curved road. SOLUTION: An image data which has recognized three-dimensionally the road before the car and traffic environment is obtained by means of an image recognition means 27, a curved road is detected by the image data through a curved road detecting means 41 before going in a curved road, and when a turning car speed detecting means 43 detects the curved road, a turning car speed VC at which a standard driver makes a turn is calculated on the basis of the radius of curvature and the width of the traffic lane contained in the image data. Then, judgement is made when the curve is steep or not by comparing the turning car speed VC with the actual car speed VS before going in the curved road by means of a steep curve judgement means 44, and when a braking state judgement means 45 judges that the curve is steep, and when the driver does not perform evading operation even when passing a braking start point LB at which the standard driver performs speed reduction operation, an alarm signal is generated.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an alarm device for assisting a driver in safe driving while traveling in a vehicle such as an automobile, and more particularly to an alarm device for improving traveling safety on a curve road.

[0002]

2. Description of the Related Art In recent years, in order to dramatically improve the safety of vehicles against the increasing tendency of traffic accidents, a comprehensive driving support system (ADA, Active) that actively assists driving operation
DriveAssist System) is being developed. In this system, it is essential to recognize the external environment of the vehicle, but by processing the image information of the scenery and objects in front of the vehicle captured by multiple cameras, the road and traffic environment can be processed with sufficient accuracy and time for practical use. It has become possible to recognize three-dimensionally. Therefore, the ADA system uses the image data of the road and traffic environment to detect a collision, a lane departure, etc., when the driver makes an operation error, looks away, or falls asleep during monotonous driving. The aim is to predict whether there is a possibility and to assist from various angles to lead to the safe side.

Here, as a way of providing driving assistance, preventive safety (not to be in a dangerous state from the beginning) is first attempted based on the idea that a car is operated by a human being. That is,
When a possibility of collision or lane departure is predicted, an alarm is sounded to assist the driver in safe driving. If the driver does not perform appropriate avoidance operation even after sounding the alarm, the brake, throttle, or steering operation system is automatically controlled to a safe side to avoid a collision or lane departure, It has been proposed to assist directly to act as a temporary agent.

Therefore, the alarm in the ADA system is very important for predicting various possibilities and improving preventive safety. Therefore, what is the possibility for what in any situation is determined, and the image data is determined. -It is necessary to make effective use of the information of the data to accurately predict the possibility, and to appropriately issue an alarm in a state where the driver can perform an avoidance operation. Here, as one of various possibilities, there is a possibility of deviation from a road or a lane on a curve road such as a sudden curve. In particular, in a sudden curve such as an interchange immediately after leaving the highway, the sense of speed is too high and the speed of entry into the curve is high, which makes it easy to depart from the lane.
It is desirable to give an appropriate warning to this.

Conventionally, as a warning device for preventing lane departure on the above-mentioned curved road, for example, there is a prior art of Japanese Utility Model Laid-Open No. 5-46612. In this prior art, the state of the vehicle is determined from the vehicle speed and the lateral acceleration for each range of the steering angle, and, for example, when it is determined that the vehicle speed and the lateral acceleration have increased when the vehicle turns by a predetermined steering angle, an alarm is issued, It is shown to prevent lane departure due to overspeed.

[0006]

By the way, the above-mentioned prior art is a method for judging the lateral acceleration while actually turning, and is a method for judging the lateral acceleration when entering a curve road. It does not prevent lane departure due to overspeed. Further, since there is no information such as the actual radius of curvature of the curved road and the width of the lane, there is a problem that the accuracy of judgment is low.

In view of the above points, the present invention aims to predict the possibility of lane departure due to an overspeed and to issue an appropriate warning before entering a curved road. To do.

[0008]

In order to achieve this object, a vehicle alarm system according to claim 1 of the present invention recognizes a road ahead of a vehicle and a traffic environment three-dimensionally, as shown in FIG. Image recognizing means for obtaining the image data, a curve path detecting means for detecting the curve path by the image data before entering the image path, and an image data of the image data when the curve path is detected. curvature radius,
A turning vehicle speed calculation means for calculating a turning vehicle speed VC when a standard driver turns based on the width of a lane, and a turning vehicle speed VC
And compare it with the actual vehicle speed VS before entering the curve road.
A sudden curve determining means for determining whether or not the vehicle is in a braking state, and a braking state determination for issuing an alarm if the avoidance operation is not performed even after the braking start point LB at which the standard driver decelerates when the sudden curve is determined. And means.

In the vehicle alarm system according to the second aspect of the present invention, the standard vehicle speed VC when the driver turns is VC = √ (GCRC) using the lateral acceleration GC and the curve radius of curvature RC.
It is characterized by being estimated by.

In the vehicle alarm system according to the third aspect, LB = (VS- using the turning vehicle speed VC and the actual vehicle speed VS when the standard driver turns the braking start point LB where the standard driver performs deceleration operation. It is characterized in that it is estimated by VC) / g * (VS + VC) / 2.

[0011]

Embodiments of the present invention will be described below with reference to the drawings. In FIG. 2, a general outline of the vehicle and the ADA system will be described. First, in the vehicle 1, the engine 2 is connected to the rear wheel 10 via the clutch 4, the transmission 5, the propeller shaft 6, the rear differential device 7, the rear axle 8, etc. Device 1
8, front wheel 9, and the like, are connected to front wheels 9, and front and rear wheels 9 and 10 are driven so that they can travel. As a driving operation system of the vehicle 1, an accelerator pedal 11 is provided so as to open and close the throttle valve 3 of the engine 2 to change the engine output. Further, the brake device 12 is provided so that the brake pressure is introduced to the wheel cylinder side of the front and rear wheels 9 and 10 by the brake conduit 14 by the operation of the brake pedal 13 to brake. Further, the steering device 15 is provided so as to steer the front wheels 9 by operating the steering wheel 16.

The ADA system 20 is provided with a throttle actuator 21 on the throttle valve 3 as various actuators for vehicle control so that the engine output can be increased or decreased by a throttle signal. Further, a break actuator 22 is provided in the break conduit 14 of the break device 12 so as to automatically increase and decrease the break pressure by a break signal. Further, a steering actuator 23 is provided in the steering device 15 so as to automatically steer by a steering signal.

The electronic control system will be described. As the image recognition means, for example, two Cs arranged on the left and right sides of the vehicle 1
It is equipped with a CD camera 25 and an image recognition unit 26 of a stereo image processor. Two CCD cameras 25
Captures a landscape or an object in front of the vehicle by stereo imaging. The image recognition unit 26 includes two CCD cameras 25.
The image signal picked up in (3) is processed by the triangulation method based on the stereo method to calculate the distance, and a distance image having a three-dimensional distance distribution on the entire screen is created. Then, lanes, preceding vehicles, obstacles, etc. are separated and detected from the distance image, and the left and right white lines, the three-dimensional shape of the road, etc. are recognized from the lanes. Further, it recognizes what the front object is, the relative distance to the preceding vehicle and obstacles, the speed, etc., and thus obtains the image data of the road and the traffic environment.

The ADA control unit 40 has an alarm control system for predicting various possibilities and issuing an alarm, a vehicle control system in the case where the driver does not avoid the operation despite the alarm. The vehicle control system calculates the acceleration / deceleration from the image data by various other sensor signals so as to maintain a safe distance with respect to a preceding vehicle or an obstacle on the road, and an appropriate throttle based on this acceleration / deceleration. The throttle signal of the opening is output to the throttle actuator 21 to control the engine output.
In addition, a brake signal of an appropriate brake pressure based on acceleration / deceleration is output to the brake actuator 22 for automatic brake control, so that the safe inter-vehicle distance can be maintained when the driver does not make an operation error or avoids an operation. It is possible to keep it on or prevent collision. On the other hand, the target trajectory at the predetermined distance position on the image is set, and the predicted trajectory when the vehicle travels at the predetermined distance position in the current traveling state is calculated and according to the deviation between the target trajectory and the predicted trajectory. The steering signal is output to the steering actuator 23 for automatic steering control,
In the case of a driver's operation error, it is possible to avoid a collision and prevent the vehicle from deviating from the lane.

As one of the warning devices, a warning control system for a lane deviation on a curve road will be described. First, before entering the curve road, information such as the radius of curvature of the curve road and the width of the lane in the image data is taken out. Further, a vehicle speed sensor 30 for detecting a vehicle speed is provided, an accelerator sensor 31 for detecting an accelerator OFF and a brake switch 32 for detecting a brake ON are provided as deceleration operation signals of the driver, and acceleration is detected as a deceleration signal. It has an acceleration sensor 33. Then, based on these information, signals from sensors and switches, a sudden curve on the curve road is judged before entering the curve road to predict the possibility of lane departure, and an alarm is issued at the alarm 34. Composed.

Next, the rapid curve determination method and alarm control according to the present invention will be described with reference to the functional block diagram of FIG. 3 and the flow charts of FIGS.
Explain by chart. First, while the vehicle is running, two C
The image signal captured by the CD camera 25 is processed by the image recognition unit 26 to obtain image data of road and traffic environment (step S1). This image data is input to the curve road detecting means 41 of the ADA control unit 40, and if there is a curve road C in front of the vehicle as shown in FIG. C is detected (step S2).

When the curve path C is detected, the curve path C is detected.
At a point before this, information on the maximum curvature radius R of the curve road C and the width W of the lane in the image data is taken out, and the actual vehicle speed VS and the sudden curve before the curve road C by the vehicle speed sensor 30 are taken out. The distance L to the camera is read (step S3). Then, in the curve radius calculation means 42, the width of the lane of the curve C is taken into consideration based on the radius R of curvature of the image data and the width W of the lane, and the out-in-out using the entire width of the lane. The radius of curvature of the curve R, which is the maximum turning radius on the curve C when traveling
C is calculated by RC = R + W (step S4).
After that, the turning vehicle speed calculating means 43 calculates the turning vehicle speed VC when the standard driver turns the curve path C by using the lateral acceleration GC (for example 0.4 G) and the curve radius of curvature RC. It is calculated and estimated by VC = √ (GC · RC) (step S5). As a result, even if the actual curve path C has a wide lane width even if the radius of curvature R is large, the lane width is narrow, or even if the radius of curvature R is small, the lane width is wide.
The turning vehicle speed VC that does not cause a lane departure is accurately obtained in advance.

Then, the sudden curve judging means 44 compares the actual vehicle speed VS before entering the curve C with the turning vehicle speed VC to judge whether or not it is a sudden curve (step S6). When the vehicle speed VS is smaller than the turning vehicle speed VC, it is judged that the vehicle is not in a sudden curve, and the process ends. On the other hand, when the vehicle speed VS is higher than the turning vehicle speed VC, it is determined that the vehicle is a steep curve that may depart from the lane when entering the curve C at the current vehicle speed VS (step S7). Therefore, the driver recognizes the state of the curb road C in front of him and the current vehicle speed VS of the vehicle 1 and keeps the vehicle speed VS sufficiently low, or the vehicle speed VS is the radius of curvature of the carve road C or If it is judged that the vehicle speed is higher than the turning vehicle speed VC estimated from the width of the lane and the vehicle decelerates earlier, the possibility of deviating from the lane is reduced and the alarm is not sounded. Then, the vehicle 1 enters the curve C at this vehicle speed VS and turns normally.

When it is determined that the curve is sudden, the lane departure determining means 45 causes the accelerator sensor 31 and the brake switch 32.
The deceleration operation signal is checked to determine whether the driver has made an avoidance operation (step S8). When the deceleration operation signal is input, it is determined that the driver has performed the avoidance operation, and the process ends. On the other hand, when the deceleration operation signal is not input, it is determined that the driver does not perform the avoidance operation, and the process proceeds to the alarm subroutine (step S9).

As shown in FIG. 5, the alarm subroutine first calculates the braking start point LB at which the standard driver starts braking when the vehicle suddenly enters the front of the vehicle (step S11). The calculation is LB = (VS-
VC) / g * (VS + VC) / 2. Here, VC represents the turning speed of a standard driver, for example, turning lateral G is 0.
2 is calculated as VC = √ (R * 0.2 * 9.8). Then, the distance L to the sudden curve read in step S3 is compared with the braking start point LB (step S1).
2). If L> LB, the alarm will not sound because the distance to the sudden curve is sufficient. On the other hand, when L≤LB, a standard driver has passed a point where braking should be applied, so that the possibility of the vehicle 1 deviating from the lane on the curve C is predicted and an alarm 34 is issued. Is sounded (step S13). As a result, an alarm sounds before entering the curve road C, and even if the driver notices the alarm and decelerates, he or she can suffice, and the vehicle 1 is decelerated by the avoiding operation. When the vehicle enters C, the driver's safe driving is assisted so as to prevent the vehicle from departing from the lane.

Although the embodiment of the present invention has been described above, the signal of the acceleration sensor 33 may be used as the deceleration signal of the driver. Further, in the embodiment of the present invention, an example in which the alarm means is used as the alarm 34 has been described. However, as long as the alertness of the driver can be enhanced, a display device or a seat provided in the driver's visual field is provided. It may be a cushion or a vibrating device which is installed in the seat back and generates vibration.

[0022]

As described above, in the vehicle alarm system according to the first aspect of the present invention, the image recognition means for obtaining the image data in which the road ahead of the vehicle and the traffic environment are three-dimensionally recognized. , A standard curve path detecting means for detecting a curve path by the image data before entering the vehicle, and a standard based on the radius of curvature of the image data and the width of the lane when the curve path is detected. A turning vehicle speed calculation means for calculating the turning vehicle speed VC when the driver turns, and a turning curve for judging whether or not the turning is a sudden turn by comparing the turning vehicle speed VC with the actual vehicle speed VS before entering the turning path. -Because it is configured to include a valve determination means and a braking state determination means for issuing an alarm when the avoidance operation is not performed even after the braking start point LB where the standard driver decelerates when a sudden curve is determined, Even when the vehicle reaches the point where braking should start when entering the curve road, deceleration operation is performed. It is is intended to emit an alarm if not, mosquitoes without emitting a unnecessary alarms - can reliably assist safe driving of the driver in the blanking circuit.

In the vehicle alarm system according to the second aspect of the present invention, the turning vehicle speed VC when the standard driver makes a turn is set to the lateral acceleration GC.
And the radius of curvature of the curve RC and the lane width, VC = √
By estimating with (GC / RC), it is possible to highly accurately estimate the turning vehicle speed based on the image information.

In the vehicle alarm system according to the third aspect of the invention, the turning vehicle speed VC and the actual vehicle speed VS when the standard driver turns at the deceleration start point LB where the standard driver performs deceleration operation.
LB = (VS-VC) / g * (VS + VC) / 2
As a result, it is possible to perform braking without a feeling of strangeness when entering the curve.

[Brief description of drawings]

FIG. 1 is a diagram corresponding to a claim showing a configuration of an alarm device for a vehicle according to the present invention.

FIG. 2 is an explanatory diagram showing an outline of an entire vehicle and an ADA system.

FIG. 3 is a functional block diagram of an alarm device of the present invention.

FIG. 4 is a flowchart showing the overall control of the present invention.

FIG. 5 is a flowchart showing the control by the braking state determination means of the present invention.

FIG. 6 is an explanatory diagram showing a state of a curve path.

[Explanation of symbols]

 27 image recognition means 41 curve road detection means 43 turning vehicle speed calculation means 44 sudden curve determination means 45 braking state determination means

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁶ Identification code Agency reference number FI Technical display location B62D 111: 00 113: 00 137: 00

Claims (3)

[Claims] 1. An image recognition means for obtaining image data in which a road ahead of a vehicle and a traffic environment are three-dimensionally recognized, and a curve road for detecting a curve road before the approach by the image data. Detecting means, a slewing vehicle speed calculating means for calculating a slewing vehicle speed VC when a standard driver makes a turn based on the radius of curvature of image data and the width of a lane when detecting a curve road, and a slewing vehicle speed VC. And the actual vehicle speed VS before entering the curve road, and a sudden curve judging means for judging whether or not there is a sudden curve, and a standard driver performing deceleration operation when the sudden curve is judged. An alarm device for a vehicle, comprising: a braking state determining means for issuing an alarm when the avoidance operation is not performed even after passing the braking start point LB. 2. A turning vehicle speed VC when a standard driver turns is obtained by using a lateral acceleration GC and a curve radius of curvature RC.
2. The vehicle alarm system according to claim 1, wherein the alarm is estimated by VC = √ (GCRC). 3. The braking start point LB at which the standard driver operates to decelerate is a turning vehicle speed V when the standard driver turns.
Using C and the actual vehicle speed VS, LB = (VS-VC) / g
The vehicle alarm device according to claim 1 or 2, wherein the alarm device is estimated by * (VS + VC) / 2.