JP2001175999A - Lane departure suppression device - Google Patents

Abstract

(57) [Summary] [PROBLEMS] To prevent a driver from feeling uncomfortable due to a continuous warning sound, and to perform a lane departure suppression process other than the warning sound in a state where the driver may still have a lane departure. Be able to let them know that there is something. A traveling position detecting means detects or estimates a position of a vehicle with respect to a traveling lane. Next, the lane departure determination unit 5 determines whether the vehicle is in a lane departure risk state based on a plurality of lane departure determination criteria set according to the risk of departure of the vehicle from the traveling lane. And control means 6
Starts the warning sound and other lane departure suppression processing when the vehicle enters the lane departure dangerous state, and ends the warning sound when the vehicle is no longer in the lane departure dangerous state based on the first lane departure determination criterion. When the vehicle is no longer in the lane departure dangerous state based on the second lane departure determination criterion having a lower degree of risk than the first lane departure determination criterion, the lane departure suppression processing other than the warning sound is ended.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a lane departure suppressing device for performing a lane departure suppressing process to prevent a vehicle from deviating from a traveling lane.

[0002]

2. Description of the Related Art In recent years, there has been developed a technology (driving assistance device) for grasping the position and attitude of a vehicle with respect to a traveling road, performing automatic traveling control of a vehicle based on the information, and assisting a driver's driving. Is being developed. In the case of automatic cruise control, it is necessary to drive a car without relying on the driver at all, and various conditions such as the development of basic facilities (infrastructure) such as roads are premised on the practical application. Become.

[0003] On the other hand, in the case of a driving assistance device, the driver drives the automobile, and the driving assistance device informs the driver of a driver's driving operation error or assists driving in a direction to eliminate the error. It is. Therefore, there are many technologies for driving assistance devices that can be realized even in the current road environment, and development of driving assistance devices with higher practicality is desired.

One of such driving support devices is a lane departure suppression device. As this lane departure suppression device, there is a technology that emits an alarm sound to a driving vehicle when a vehicle is inadvertently deviating from a traveling lane. For example, JP-A-5-1049
No. 76 discloses a technique for determining the content of an alarm sound for notifying that the vehicle has deviated from the road, based on the relationship between the driver's consciousness level and the amount of lateral displacement of the vehicle. In the technology disclosed in this publication, the interval at which a buzzer sounds is changed as lane departure suppression processing, and if the degree of danger is high, a continuous sound is generated to make the driver aware of danger.

[0005]

However, the fact that the buzzer continues to sound despite the tendency of the vehicle to deviate from the departure state is very troublesome for the occupant, and the alarm sound from such a buzzer is troublesome. If it is canceled early because of that, the driver will judge that the driver has left the lane departure risk state even though there is still a risk of departure from the lane, and safety Is not preferred in terms of

SUMMARY OF THE INVENTION The present invention has been made in view of the above-mentioned problems, and it is possible to prevent an occupant from feeling uncomfortable due to continuous sounding of a warning sound, and to provide a driver with lane departure suppression processing other than the warning sound. It is now possible to indicate that the vehicle is still in a lane departure state.
It is an object to provide a lane departure suppression device.

[0007]

For this reason, in the lane departure suppressing device of the present invention, the position of the vehicle with respect to the traveling lane in which the vehicle travels is detected or estimated by the traveling position detecting means. Next, the lane departure determination means determines whether there is a risk that the vehicle deviates from the vehicle lane from the vehicle position. Then, when the control means determines that the vehicle is in a lane departure danger state, the lane departure suppression processing is controlled to be performed. In particular, the lane departure determination means determines whether the vehicle is in a lane departure risk state based on a plurality of lane departure determination criteria set according to the risk of departure from the traveling lane of the vehicle. The control means starts the first lane departure suppression process using an alarm sound and the second lane departure suppression process other than the first lane departure suppression process when it is determined that the vehicle has entered the lane departure danger state. If it is determined that the vehicle is no longer in the lane departure dangerous state based on the first lane departure determination criterion of the plurality of lane departure determination criteria, the first lane departure suppression process is terminated, and Also, if it is determined that the vehicle is no longer in the lane departure risk state based on the second lane departure determination criterion having a low degree of danger, the second lane departure suppression process is terminated.

[0008]

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a perspective view of a lane departure suppressing device according to an embodiment of the present invention; FIG. This lane departure suppression device performs lane departure suppression processing in order to prevent the vehicle from deviating from the driving lane in the automobile, recognizes the position of the host vehicle with respect to the driving lane, and detects the lane departure. When the fear arises, FIG.
As shown in FIG. 5, a lane departure suppression process for generating an alarm sound by a warning device 26 provided in the vehicle to warn the driver is performed, and a steering wheel (hereinafter, also referred to as a steering wheel) is provided by a vibration actuator 27 provided in the vehicle 1. 20) or give a steering torque different from the steering torque applied by the driver by the steering actuator 21 (this steering torque is referred to as a steering control torque to distinguish it from the steering torque applied by the driver). Thus, a lane departure suppression process for alerting the driver through the steering wheel 20 is performed.

[0009] The steering control torque itself has the effect of correcting the behavior of the vehicle.
The main purpose is to alert the driver through the steering system, and the position of the vehicle that is likely to deviate from the lane is corrected by the driver who recognizes that the vehicle is likely to depart from the lane due to the application of this steering control torque. It is to be performed by the steering operation of.

For this reason, as shown in FIG. 1, the present lane departure suppression device includes a camera 2 as an image pickup means for picking up an image of a road condition ahead of the vehicle 1 in order to recognize the position of the own vehicle with respect to the traveling lane. An image information processing means 3 for appropriately processing image information from image information from the camera 2 to recognize left and right white line positions on a front road; Driving lane)
And a lateral shift amount calculating means 4A for predicting and calculating the lateral shift amount ΔY after a predetermined time with respect to the reference position.

It should be noted that the lateral deviation amount ΔY corresponds to a determination parameter relating to the degree that the vehicle 1 is likely to depart from the lane. The lateral displacement amount calculating means 4A is provided as a functional element in the traveling lane estimating means 4 for estimating the relative position of the traveling lane (traveling lane) with respect to the own vehicle. The travel lane estimation means 4 constitutes a travel position detection means for detecting or estimating the position of the vehicle with respect to the travel lane in which the vehicle travels.

Here, the recognition of the position of the host vehicle with respect to the traveling lane, that is, the calculation of the lateral displacement ΔY of the host vehicle will be described first. In the image information processing means 3, first, as shown in FIG. 2, an original image 41 from the camera 2 is taken in, a road white line is extracted from the original image 41, and the image of the extracted road white line is viewed from above vertically. The image is converted into such a two-dimensional image 42.

Next, recognition of the white lines 12L and 12R will be described with reference to FIG. Here, the recognition of the white line 12L as the roadside line at the left end of the traveling lane will be described. However, the same applies to the case where the white line 12R at the right end of the traveling lane is used as a reference. I will call it. Next, in the image information recognizing means 3, as shown in FIG. 3 (a), the camera 2 provided in the vehicle 1 captures monochrome image information in a range in front of the vehicle (for example, 5 m to 30 m) on flat ground, and Some images in the vertical direction on the screen are omitted from the information.
Then, a plurality of horizontal lines 11 are set at equal intervals on this screen.

The fetching of the black and white image information is updated every minute control cycle. As shown in FIG. 3B, the white line position on the previous screen on each horizontal line 11 is determined. The required range on the left and right (here, 5
0 pixel [dot]) is the white line search area (processing target area)
Set as 10. For the first screen, the white line position on the straight road is used as the previous screen data.

Then, as shown in FIG. 3C, the brightness of each horizontal line is differentiated in the horizontal direction from the left. Reference numeral 14 in the figure is a guardrail. By the way, a normal road surface has low luminance and a small change in luminance. On the contrary,
Since the brightness of the white line 12 is much higher than that of the normal road surface, when the brightness of the road is differentiated in this way, the luminance change is positive at the boundary point from the normal road surface to the white line 12, and the white line 12 changes to the normal road surface. Differential data is obtained such that the luminance change becomes negative at the boundary point of. An example of such differential data is shown in FIG.

Then, for each data of each horizontal line 11, peaks of the differential values appear in the order of plus and minus from the left, and the interval between the peaks is the white line 12.
Is extracted as a candidate for a white line, and a combination that falls within a reasonable degree (interval between a positive peak and a negative peak is within 30 dots, for example) is extracted.
As shown in FIG. 3E, the midpoint M is set to the white line candidate point 15.
Save as

Then, among these white line candidate points 15,
Only the point closest to the screen center is left as the final candidate point.
This means that, for example, when the vehicle 1 is traveling on the left side, the search area 1
The right side of 0 is a road surface with little change in normal luminance, and the white line candidate point 15 closest to this normal road surface can be determined as the white line 12. Therefore, further to the left of the white line 12,
Objects that cause noise (for example, guardrails 14)
Is present, the white line 12 can be reliably recognized from the image information captured by the camera 2.

Finally, as shown in FIG. 3F, the vertical continuity of the white line candidate points 15 in each horizontal line data is sequentially verified from the bottom of the screen. First, the inclination between the upper and lower ends of the white line 12 on the previous screen is calculated in advance.
Then, assuming that the lowest point 15A is the white line 12, it is verified whether or not the candidate point 15B on the horizontal line 11 which is only one line above is within the range of ± 50 dots of the inclination of the previous white line 12.

If the candidate point 15B falls within this range, it is regarded as a white line. If not, the candidate point 15B is rejected, and the coordinates obtained by interpolation from the above-mentioned inclination are regarded as the white line position. By performing the same operation for each horizontal line for this detection, a continuous white line 12 can be recognized. Such white line recognition work is continuously performed at a required cycle, and the recognition of the white line 12 is updated each time.

A white line 12 as a roadside line at the right end of the traveling lane
The recognition of R is performed in the same manner. In the estimating means 4, the original image 41 thus recognized in each recognition cycle
The upper white lines 12R and 12L are converted into a two-dimensional image 42,
The road center line LC is estimated based on the road center line LCL that can be estimated from the white line 12L at the left end of the traveling lane and the road center line LCR that can be estimated from the white line 12R at the right end of the traveling lane. And this road center line LC
, The lateral displacement amount ΔY0 and the deflection angle β at the present time are calculated by the lateral displacement amount calculating means 4A.

The declination β is the angle between the tangent to the curved road center line LC and the direction of the vehicle center line, as shown in FIG. Reference line position information at a first detection point (shown as a perigee in the figure) which is a close detection level, and a second detection point (a predetermined distance L at a current vehicle speed V) further from the vehicle 1 than this perigee (The point arriving after the time t, which is shown as an apogee in the figure).

That is, the argument β is calculated as an angle between a straight line connecting the first detection point and the second detection point and the center line of the vehicle 1. The declination calculated in this way is a declination at an intermediate point between the first detection point and the second detection point (indicated by x in the drawing), and is a declination at least a point ahead of the vehicle 1 by a certain distance or more. . In this example, the lateral distance (the road width direction, that is, the camera image) between the vehicle center line (see the point P1) and the road center line LC (see the point LC1) at the first detection point closest to the vehicle at the first detection point. Is calculated as the lateral displacement amount (current lateral deviation) ΔY0 at the present time. The second detection point is the first detection point.
It is a point (LC2, P2) that can be predicted to arrive after a predetermined time t from the detection point, that is, a point that is separated from the first detection point by a distance L obtained by multiplying the current vehicle speed V by the predetermined time t. First detection point (LC1) and second detection point (LC1)
The angle formed between the straight line connecting the detection point (LC2) and the center line (P1P2) of the vehicle 1 is calculated as the declination β.

The lateral deviation calculating means 4A multiplies the deviation angle β calculated as described above by the vehicle speed V of the vehicle detected by the vehicle speed sensor 32 and a predetermined time t to calculate the lateral deviation change amount Δy ( .DELTA.y = .beta..times.V.times.t) and adds the current lateral displacement (lateral deviation) .DELTA.Y0 to the predicted lateral displacement (hereinafter simply referred to as lateral displacement) .DELTA.Y (= .DELTA.Y).
0 + β × V × t). Further, the curvature (road curvature) ρ of the traveling lane is estimated based on the image information of the road center line. The predetermined time t is set to an appropriate time in consideration of the driver's general operation speed of the steering wheel 20 and the speed of recognition of road conditions by the image information processing means 3 and the like. Further, it may be variable according to the vehicle speed V, and the predetermined time t may be set so that the distance L from the first detection point to the second detection point is constant.

The lane departure judging means 5 of the present embodiment calculates the lateral deviation amount (lateral deviation) calculated by the lateral deviation amount calculating means 4A.
Based on ΔY, the degree of departure from the lane (the degree of risk of lane departure), that is, the lane departure determination is performed. That is, the lane departure determination means 5 determines the lateral deviation amount ΔY of the vehicle with respect to the reference position of the traveling lane (center position of the road width) calculated as described above as the determination value (departure determination reference) ΔY.
When s is exceeded, it is determined that the vehicle deviates from the lane, and a lane departure signal (also indicating the lane departure direction) is output to a controller 6 described later. The lane departure determination unit is configured to determine whether there is a risk of the vehicle 1 deviating from the traveling lane based on the vehicle position detected by the traveling position detection unit.

Here, a plurality of judgment values are set so that the lane departure judgment can be performed in a stepwise manner according to the degree of departure from the lane. In other words, in order to determine whether or not the vehicle is likely to depart from the lane (low danger state), a small danger state determination value (lane departure determination criterion, second
Lane departure determination standard) ΔYs ₂₁ is set. The lane deviation determining means 5 is adapted between do lane departure determination that the risk small state lateral deviation ΔY of the vehicle is greater than the risk small state judging value ΔYs _21. When the lane departure determination unit 5 determines that the vehicle is in the low-risk state as described above, the lane departure determination unit 5 generates a steering control torque (steering wheel return torque) by the steering actuator 21 to be described later [based on the steering control torque. Warning (second warning), first-stage warning] to perform lane departure suppression processing (second lane departure suppression processing).

In order to determine whether or not the vehicle is likely to depart from the lane in a state higher than the low-risk state (medium-risk state), a medium-risk state determination value (lane departure criterion, second Lane departure determination standard) ΔYs ₂₂ (ΔYs ₂₂ > ΔY)
s ₂₁₎ has been set. And the lane departure determination means 5
Means that the lateral deviation amount ΔY of the vehicle is equal to the medium risk state determination value ΔY.
While exceeded s ₂₂ is adapted to perform the lane departure determination that is in risk status. When the lane departure determination unit 5 determines that the vehicle is in the middle danger state as described above, an alarm that vibrates the steering wheel 20 by the vibration actuator 27 described below (an alarm due to steering wheel vibration (second alarm), The second lane alarm] performs lane departure suppression processing (second lane departure suppression processing).

Further, in order to determine whether or not the vehicle is likely to deviate from the lane (high danger state), a high danger state determination value (lane departure determination standard, first lane departure determination standard) ΔYs ₁₀ (ΔYs ₁₀ > ΔYs ₂₂ ) is set. The lane deviation determining means 5 is adapted between do lane departure determination that risk is greater state lateral deviation ΔY of the vehicle is greater than the risk atmospheric state determination value ΔYs _10. When the lane departure determination unit 5 determines that the vehicle is in the high-risk state as described above, an alarm that generates an alarm sound by the alarm device 26 described later [alarm by alarm sound (first alarm), Lane departure suppression processing (first lane departure suppression processing).

It should be noted that the above-described small risk state determination value ΔY
s ₂₁ , the medium-risk state determination value ΔYs ₂₂ , and the large-risk state determination value ΔYs ₁₀ are all set as values corresponding to the lateral deviation amount ΔY of the vehicle. Of these, the small-risk state determination value ΔYs ₂₁ is set as the smallest value (the distance from the road center line is the shortest), the medium risk state determination value ΔYs ₂₂ is set as the next smallest value, and the high risk state determination value Δ
Ys ₁₀ is (the distance between the center line of the road farthest) largest value is set as.

Here, if the determination value is set to a small value, the determination that the vehicle 1 departs from the lane is made earlier. That is, in the present embodiment, the determination as to the small risk state determined by the small risk state determination value is made earliest (the alarm start timing is earlier), and then the determination is made using the medium risk state determination value. In this case, it is determined that the state is the medium risk state and the high risk state is determined in accordance with the large risk state determination value (the alarm start timing is delayed in order).

If the judgment value is set to a large value,
The determination that the vehicle 1 deviates from the lane is released earlier. That is, in the present embodiment, the release of the determination that the vehicle is in the high-risk state determined by the high-risk state determination value is earlier (the alarm end time is earlier), and then the determination is made by the medium-risk state determination value. It is determined in order that the state is the medium risk state to be performed and the small risk state is determined by the small risk state determination value (the alarm end time is later in order).

As a result, the period during which it is determined that the vehicle is in the low-risk state is longer, the period during which the vehicle is determined to be in the medium-risk state is shorter than this period. The period in which the determination is made is shortened. Then, as described later, the warning by the warning sound performed when it is determined that the state of high risk is high is not performed for a long time. Further, the warning that is performed when it is determined that the vehicle is in the medium risk state or the low risk state is performed for a longer period than the warning by the warning sound.

In the present embodiment, the lane departure determination for the low risk state, the medium risk state, and the high risk state and the release determination of these lanes are performed using the same determination value. Alternatively, the determination may be performed using different determination values. By the way, the present lane departure suppression device controls the steering torque applied by the driver so as to issue a lane departure warning based on the lane departure determination by the lane departure determination means 5 (determination that the vehicle is likely to deviate from the traveling lane). Separately, a steering actuator 21 that can apply a steering control torque to the steering system, a vibration actuator 27 that can vibrate the steering wheel 20, an alarm 26 that emits an alarm sound, the steering actuator 21, the vibration actuator 27, and the alarm And a controller (control means) 6 for controlling the controller 26.

First, the steering actuator 21 may be any actuator that can apply a torque to the steering shaft. For example, as shown in FIG. 5, the steering actuator 21 is installed below the torsion bar (not shown) of the steering shaft 40 (on the power steering side). It may be constituted by the small electric torque motor 41 described above. In this case, torque transmission from the motor 41 to the steering shaft 40 is performed via a worm gear 42 including a worm 42a and a worm wheel 42b, and a torque limiter 43 is provided between the worm wheel 42b and the steering shaft 40.
Intervene. The torque limiter 43 allows the driver to easily operate the handle 20 even if the motor 41 is stuck. Also, the motor 41
The maximum torque is set to a necessary minimum, so that even if a failure occurs in the controller 6, an excessive steering burden is not given to the driver.

The vibration actuator 27 includes the handle 2
As long as it is an actuator that can apply vibration to zero, FIG.
As shown in FIG. Note that, as the vibration actuator 27, an actuator configured similarly to the steering actuator 21 described above may be used. The alarm 26 is configured to generate an alarm sound such as a buzzer.

The controller 6 performs the following control based on the lane departure judgment of the lane departure judgment means 5. That is, the controller 6 controls the steering actuator 21 based on the lane departure determination of the lane departure determination unit 5 indicating that the danger degree is small, so that the steering control torque is generated in a direction to decrease the lateral deviation amount ΔY. It is comprised as what has.

Here, while the lane departure judging means 5 makes the lane departure judgment indicating that the danger level is low, the controller 6 controls the steering control torque so as to reduce the lateral deviation ΔY. If the lane departure determination means 5 determines that the state of danger is low,
As the lane departure suppression process, the control of the steering actuator 21 is started so that the steering control torque is generated in a direction to reduce the lateral deviation amount ΔY, and thereafter, the lane departure determination unit 5 determines that the state is no longer in the low risk state. Then (when the determination of the lane departure from the low risk state is released), the control of the steering actuator 21 for generating the steering control torque in the direction of decreasing the lateral deviation amount ΔY is ended.

More specifically, the controller 6 sets the steering control torque based on the lateral deviation ΔY of the vehicle 1 with respect to the reference position of the traveling lane (the center position of the road width) calculated as described above. Has become. In other words, unlike the steering torque used for automatic steering, the main purpose of the steering control torque is to alert the driver, and the position of the vehicle is corrected by the driver's steering operation.
The steering control torque is limited to a magnitude that does not hinder the driver's steering operation, that is, a magnitude that the driver can easily overcome.

For this reason, even when the steering control torque is applied in a direction to avoid the departure when the vehicle is likely to deviate from the lane, if the driver tries to perform the steering operation in the direction deviating from the lane, it is sufficient. You can do this.
This makes it possible to easily perform emergency steering for retreating the vehicle out of the travel lane, and does not hinder the lane change even if the steering control torque is applied during the lane change.

Thus, the driver senses the departure from the lane (departure from the center line of the road) and the direction of the correction from the feeling of holding the steering wheel 20 or the like, so that the vehicle position can be corrected promptly by the driver's steering operation. Become. The steering control torque itself is effective not only for the purpose of warning the driver, but also for correcting the vehicle position. Further, the warning by the steering control torque is also effective for a driver who looks aside, for example. In this case, the driver is encouraged to prevent the driver from looking aside while preventing a deviation from the lane.

Further, the controller 6 repeatedly generates a torque in the circumferential direction of the steering shaft 40 to vibrate the steering wheel 20 based on the lane departure determination of the lane departure determination means 5 indicating that the vehicle is in the middle danger state (see FIG. 4). It also has a function of controlling the vibration actuator 27 so that it occurs intermittently. Here, while the lane departure determination means 5 is performing the lane departure determination that the vehicle has entered the medium danger state, the controller 6 sets the medium danger state by the lane departure determination means 5 to vibrate the steering wheel 20. When it is determined, as the lane departure suppression processing, the control of the vibration actuator 27 for vibrating the steering wheel 20 is started. When the lane departure determination that the vehicle has departed is canceled, the control of the vibration actuator 27 for vibrating the steering wheel 20 is terminated.

Further, the controller 6 has a function of controlling the alarm 26 so as to generate an alarm sound based on the lane departure judgment of the lane departure judging means 5 indicating that the degree of danger is high. Here, while the lane departure determination unit 5 is performing the lane departure determination indicating that the vehicle is in the high risk state, the lane departure determination unit 5 causes the alarm 26 to generate an alarm sound. When the lane departure is determined to be in the state, the lane departure suppression processing starts control for generating an alarm sound by the alarm 26, and thereafter, the lane departure determination unit 5 determines that the danger is no longer high. When the determination is made (when the determination of the lane departure that the state of danger has become large is cancelled), the control of the alarm 26 is terminated.

By the way, the controller 6 operates the steering actuator 21, the vibration actuator 27 and the alarm device 2 as alarm means (lane departure suppressing means) in this way.
Next, the timing (control start timing and control end timing) at which each of these controls (lane departure suppression processing) is performed will be described with reference to FIG. In FIG. 6, indicates the start and end times of the alarm by the alarm sound, indicates the start and end times of the alarm by the steering wheel vibration, and indicates the start and end times of the alarm by the steering control torque. In FIG. 6, ○ indicates an alarm start time, and X indicates an alarm end time.

In this embodiment, as shown in FIG. 6, the vehicle 1 traveling on the road center line (the position indicated by (a) in FIG. 6) deviates from the road center line, and the lane departure judging means 5 Once beyond the lateral deviation ΔY is risk small state judging value DerutaYs ₂₁ of the vehicle 1 is determined to have become the risk small state by [in FIG. 6, (b) position indicated by], steering control torque lateral deviation amount ΔY The control of the steering actuator 21 is started so as to occur in a direction to reduce the steering angle. Thus, a warning is issued to the driver so as to perform appropriate steering without departing from the lane.

Even though such a warning is given, no action is taken by the driver, and the lane departure determining means 5 causes the lateral deviation amount ΔY of the vehicle to exceed the intermediate danger state determination value ΔYs ₂₂ and the danger level When it is determined that the vehicle is in the middle state (at the position indicated by (c) in FIG. 6), in addition to the control for generating the steering control torque as described above, the control of the vibration actuator 27 is started to vibrate the steering wheel. . As a result, the degree of departure from the lane is increasing, and a further warning is issued so as to perform appropriate steering without departing from the lane.

Further, despite these warnings, no action is taken by the driver, and the lane departure judging means 5 causes the lateral deviation amount ΔY of the vehicle to exceed the large danger state determination value ΔYs ₁₀ and the danger level If it is determined that the state has become large (the position indicated by (d) in FIG. 6), the steering actuator 21 and the vibration actuator 27 described above are used.
In addition to the above control, the control of the alarm 26 is started so that the alarm 26 generates an alarm sound. As a result, the degree of departure from the lane is the highest, and a final warning is issued so as to perform appropriate steering without departing from the lane.

Thereafter, appropriate steering is performed by the driver.
(The position indicated by (e) in FIG. 6), lane departure determination means
5, the amount of lateral displacement ΔY of the vehicle is determined to be the high-risk state determination value Δ
Ys _TenIt is judged that it is smaller than
When it is determined (the position indicated by (f) in FIG. 6),
Steering actuator 21 and vibration actuator 2
7 only, no alarm sound from alarm 26
Then, the control of the alarm 26 is ended. This
The alarm 26 from the alarm 26
The trouble caused by the steering actuator 21 is eliminated.
And the control by the vibration actuator 27 is continued,
Drivers may still depart from the lane
Inform

In accordance with the control by the steering actuator 21 and the vibration actuator 27, appropriate steering is further performed by the driver.
The vehicle lateral deviation amount ΔY is determined by the intermediate danger state determination value ΔY.
[In FIG 6, (g) position indicated by] If it is determined that leaving the moderate risk status is smaller than s _22, and only the control of the steering actuator 21 for generating a steering control torque as described above Then, the control of the vibration actuator 27 for vibrating the handle 20 is ended so that the handle 20 does not vibrate. This informs the driver that the possibility of departure from the lane is further reduced. Even in this case, since the control of the steering actuator 21 for generating the steering control torque is continued,
The driver is informed that there is still the possibility of leaving the lane.

Further, an appropriate steering is performed by the driver, and the lane departure judging means 5 determines the lateral deviation amount ΔY of the vehicle.
[In Figure 6, the position indicated by (h)] is if it is determined that leaving the risk small state is smaller than the risk small state judging value DerutaYs ₂₁ to be such, that steering control torque does not occur, the steering The control of the actuator 21 ends. As a result, the driver is notified that there is no risk of departure from the lane. Thereafter, by appropriate steering, the vehicle 1 travels on the road center line (the position shown by (i) in FIG. 6).

In the present embodiment, a switch (SW) 23 for selecting the operation of the lane departure suppression device is provided. Therefore, the switch 23 can be turned on if the user wants to operate the device, and the switch 23 can be turned off if the user does not want to operate the device. Further, for example, in the instrument panel (instrument panel), when the switch 23 is turned on, or when a control torque is applied as a lane departure warning or when the steering wheel 20 is vibrated, an operation display is displayed. A part 24 is provided. Further, when the lane change or the like is indicated by operating the direction indicator or the like, the operation of the lane departure suppression device may be prohibited.

The image information processing means 3, traveling lane estimating means 4 (lateral deviation calculating means 4A), lane departure judging means 5, and controller 6 are electronically controlled with a CPU, an input / output interface, a ROM, a RAM and the like. It is configured as a unit. Since the lane departure suppression device as one embodiment of the present invention is configured as described above, the lane departure suppression process is performed, for example, as shown in FIG.

That is, it is determined whether or not the control switch 23 is turned on (step S10). If the control switch 23 is not turned on, the lane departure suppression processing is not performed. Is performed. In step S20, it is determined whether the lane departure determination unit 5 has set the vehicle in the low risk state, that is, the lateral deviation amount ΔY of the vehicle.
Determines becomes risk small state beyond the risk small state judging value ΔYs _21. As a result of this determination, when it is determined that the state of danger is small, the process proceeds to step S30, and the lane departure suppression processing is performed to reduce the steering control torque to the lateral deviation amount Δ.
Steering actuator 2 so that it occurs in the direction to decrease Y
1 is started.

On the other hand, if it is not determined that the low-risk state has been established, it is considered that the vehicle has departed from the low-risk state, and the process proceeds to step S80, where the control of the steering actuator 21 for generating the steering control torque is performed. And return. Next, in step S40, or was in risk status by the lane deviation determining means 5, i.e., whether now lateral deviation ΔY is in risk status beyond the risk in state judging value DerutaYs ₂₂ of the vehicle is determined . As a result of this judgment,
If it is determined that the state is in the medium risk state, step S
Proceeding to 50, as the lane departure suppression processing, in addition to the control for generating the steering control torque as described above,
The control of the vibration actuator 27 for vibrating is started.

On the other hand, if it is not determined that the vehicle is in the medium risk state, it is considered that the vehicle has left the medium risk state, and the process proceeds to step S90, where the control of the vibration actuator 27 for vibrating the handle 20 is performed. Finish,
To return. Then it determines, in step S60, or became risk atmospheric state by the lane deviation determining means 5, i.e., whether now lateral deviation ΔY is risk atmospheric conditions beyond the risk large state judging value DerutaYs ₁₀ of the vehicle. As a result of this determination, when it is determined that the state of danger is high, in addition to the control of the steering actuator 21 and the vibration actuator 27 as described above, an alarm sound is generated from the alarm 26 as lane departure suppression processing. The control of the alarm 26 is started in order to do so.

On the other hand, if it is not determined that the high-risk state has been attained, it is considered that the vehicle has left the high-risk state, and the process proceeds to step S100 to terminate the control of the alarm 26 for generating an alarm sound. And return. Therefore, according to the lane departure suppression device according to the present embodiment, the lane departure suppression process is performed by an alarm that generates an alarm sound from the alarm device 26 when the danger level is set as a relatively short period, and In the case of the medium-risk state and the low-risk state where the risk is lower than the high-risk state set as a relatively long period, an alarm other than the alarm sound, that is, the vibration
Since the lane departure suppression processing is performed by an alarm that causes vibration to occur at 0 or a steering control torque that is generated by the steering actuator 21, the alarm sounds continuously, which causes discomfort to the driver. On the other hand, even if the lane departure suppression processing by such an alarm sound is completed, the lane departure suppression processing other than the alarm sound is performed, so that the driver may still be in a lane departure state. It has the advantage of being able to inform.

In the above-described embodiment, the start and end times of the warning by the warning sound as the lane departure suppression processing, the warning by the steering wheel vibration, and the warning by the steering control torque are set to different times. However, the alarm sound is troublesome when the alarm sound lasts for a long time, so that the period for performing the lane departure suppression processing by the alarm sound is shortened as much as possible, and the lane departure suppression processing is performed after the lane departure suppression processing by the alarm sound. The processing may be performed, and the setting may be made as shown in FIGS. 8 (a) to 8 (h).

8 (a) to 8 (h), the start and end times of the alarm by the alarm sound, the start and end times of the alarm by the steering wheel vibration, and the start and end of the alarm by the steering control torque. The end time is indicated. Also,
8A to 8H, ○ indicates an alarm start time, and X indicates an alarm end time. That is, FIG.
As shown in FIG.
Similarly to the above-described embodiment, an alarm based on the steering control torque, an alarm based on the steering wheel vibration, and an alarm based on the alarm sound are set in this order, and the end time x of the alarm based on the alarm sound and the alarm based on the steering wheel vibration are simultaneously set. The end time x of the alarm based on the control torque may be set.

As shown in FIG. 8B, three alarms
, And at the same time, the ending time of the alarm by the alarm sound and the ending time of the alarm by the steering wheel vibration may be set at the same time, and thereafter, the ending time of the alarm by the steering control torque may be set. As shown in FIG. 8C, the start timing of the alarm by the steering wheel vibration and the start of the alarm by the steering control torque are set at the same time, and before that, the start timing of the alarm by the alarm sound is set. The end time x of the alarm due to the steering wheel vibration may be set at the same time, and then the end time x of the alarm due to the steering control torque may be set.

As shown in FIG. 8 (d), the start timing of the alarm by the alarm sound and the start of the alarm by the vibration of the steering wheel are set at the same time, and thereafter, the start timing of the alarm by the steering control torque is set, and The end time x of the alarm and the alarm by the steering wheel vibration may be set at the same time, and thereafter, the end time x of the alarm by the steering control torque may be set.

Further, in the above-described embodiment, the warning by the steering wheel vibration is given in the case of the medium danger state, and the warning by the steering control torque is given in the case of the small danger state. However, the present invention is limited to this. Instead, an alarm may be issued based on the steering control torque in the medium danger state, and an alarm generated by the steering wheel vibration may be issued in the small danger state.

In this case, as shown in FIG. 8 (e), the start timings of the three alarms are determined by the control torque for steering, the alarm by the steering wheel vibration, and the alarm sound in the same manner as in the above-described embodiment. The alarm may be set in the order of the alarm, and the end of the alarm by the alarm sound and the end of the alarm by the steering control torque may be set at the same time, and thereafter, the end of the alarm by the steering wheel vibration may be set.

As shown in FIG. 8F, three alarms
, At the same time, the end time of the alarm by the alarm sound and the end time of the alarm by the control torque for steering ×
May be set at the same time, and thereafter, the end time x of the alarm due to the handle vibration may be set. As shown in FIG. 8 (g), the start timing of the alarm by the steering wheel vibration and the start of the alarm by the steering control torque are set at the same time, and then the start timing of the alarm by the alarm sound is set. May be set at the same time as the end time x of the alarm by the control torque, and thereafter, the end time x of the alarm by the handle vibration may be set.

As shown in FIG. 8 (h), the start timing of the alarm by the alarm sound and the start of the alarm by the vibration of the steering wheel are set at the same time, and before that, the start timing of the alarm by the control torque for steering is set. May be set at the same time, and then the end time x of the alarm due to steering wheel vibration may be set.

In the above-described embodiment, the lane departure suppression processing by an alarm other than the alarm sound is performed by providing two judgment values of the low-risk state judgment value and the medium-risk state judgment value as the second lane deviation judgment criteria. As an example, an alarm based on steering control torque and an alarm based on steering wheel vibration are performed.
Either one may be used. In other words, the second lane departure determination criterion may be set to only the low risk state determination value, and only the warning based on the steering control torque may be performed as the lane departure suppression processing by the warning other than the warning sound. The criterion may be set to only the medium-risk state determination value, and only the warning by the steering wheel vibration may be performed as the lane departure suppression processing by the warning other than the warning sound. When the second lane departure determination criterion is only the low risk state determination value, the lane departure suppression processing by an alarm other than the warning sound is an alarm by steering wheel vibration, and the second lane departure determination criterion is the medium risk state determination value. In the case where only the alarm sound is used, the lane departure suppression processing by an alarm other than the alarm sound may be an alarm by the steering control torque. Alternatively, the second lane departure determination criterion may be set to a determination value of three or more, and three or more lane departure suppression processes by warning other than the warning sound may be performed. Furthermore, the lane departure suppression processing by the warning other than the warning sound is not limited to the warning by the steering control torque and the warning by the steering wheel vibration.
The lane departure suppression processing may be performed by controlling the braking force of the vehicle using the braking force control actuator.

In the above-described embodiment, the traveling position detecting means detects the traveling position of the vehicle from the image taken by the camera 2. However, the present invention is not limited to this. The vehicle may be configured to detect the traveling position of the vehicle with a sensor or the like, or to detect the relative position of the vehicle with respect to the lane using D-GPS navigation to determine the lane departure.

In the above embodiment, a plurality of determination values (ΔYs ₂₁ , ΔYs ₂₂ , ΔYs ₂₂₎
Ys ₁₀ ), and a plurality of (first and second) lane departure determination criteria are used.
The same operation and effect can be obtained by providing a plurality of the lateral deviation amounts ΔY determined by this determination value in a stepwise manner while using the two values. That is, the lateral deviation amount ΔY is a predicted lateral deviation at a point (apogee) LC2 (see FIG. 4) at which the vehicle arrives after the time t at the current vehicle speed V,
After this predicted lateral deviation, after t ₁ seconds, t ₂ seconds, and t ₃ seconds (t ₁ <t
₂ <t ₃ ), calculating predicted lateral deviations (lateral deviation amounts) ΔY ₁ , ΔY ₂ , ΔY ₃ at a plurality of apogees, and comparing the lateral deviation amount ΔY ₁ with one determination value ΔYs. , The lateral shift amount ΔY ₂ is determined by one determination value ΔY.
s, and the magnitude of the risk may be determined by comparing the lateral shift amount ΔY ₃ with one determination value ΔYs.

Further, in the above-described embodiment, the lane departure determination is performed based on the lateral deviation amount ΔY from the lane center of the traveling position vehicle. However, the lane departure determination is not limited to this. For example, the lane departure determination may be performed based on the separation distance between the left and right lanes and the vehicle traveling position.

[0067]

As described above in detail, according to the lane departure suppressing apparatus of the present invention, it is possible to prevent the occupant from feeling uncomfortable due to the continuous sounding of the warning sound, but to suppress the lane departure other than the warning sound. This has the advantage that the driver can be informed that the vehicle is still in a state where there is a risk of lane departure.

[Brief description of the drawings]

FIG. 1 is a block diagram schematically showing a configuration of a lane departure suppression device as one embodiment of the present invention.

FIG. 2 is a diagram illustrating image processing for driving lane recognition according to an embodiment of the present invention.

FIG. 3 is a schematic diagram illustrating traveling lane recognition according to an embodiment of the present invention in the order of (a) to (f).

FIG. 4 is a schematic plan view illustrating travel lane recognition.

FIG. 5 is a schematic diagram showing an example of a configuration of a steering actuator provided in the lane departure suppression device as one embodiment of the present invention.

FIG. 6 is a schematic diagram for explaining the start / end timing of each alarm by the lane departure suppression device as one embodiment of the present invention.

FIG. 7 is a flowchart illustrating a lane departure suppression process performed by the lane departure suppression device as one embodiment of the present invention.

FIG. 8 is a schematic diagram for explaining a modification of the start / end timing of each alarm by the lane departure suppression device as one embodiment of the present invention, and (a) to (h) each show a modification pattern. ing.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Vehicle 2 Camera 3 Image information processing means 4 Running lane estimating means 4A Lateral deviation amount calculating means (running position detecting means) 5 Lane departure determining means 6 Control means (controller) 20 Steering wheel (handle) 21 Steering actuator 22 Steering wheel 23 Switch 24 Operation display part 26 Alarm 27 Vibration actuator 32 Vehicle speed sensor 40 Steering shaft 41 Small electric torque motor 42 Worm gear 43 Torque limiter LC Road center line

Continued on the front page (51) Int.Cl. ⁷ Identification code FI Theme coat II (reference) B60R 21/00 624C F term (reference) 3D037 FA01 FA13 FA23 FA26 FB00 FB01 FB10 FB11 5C086 AA51 AA55 BA22 DA40 EA41 5H180 AA01 CC04 CC24 LL01 LL07 LL08

Claims (1)

[Claims] 1. A traveling position detecting means for detecting or estimating a position of the vehicle with respect to a traveling lane on which the vehicle travels, and a risk that the vehicle deviates from the traveling lane from the vehicle position detected by the traveling position detecting means. A lane departure determination unit that determines whether there is a vehicle, and a control unit that controls to perform a lane departure suppression process when the lane departure determination unit determines that the vehicle is in a lane departure danger state. The lane departure determination means is configured to determine whether the vehicle is in the lane departure risk state based on a plurality of lane departure determination criteria set according to the risk of departure of the vehicle from the traveling lane. The control means may include the lane departure risk condition based on any one of the plurality of lane departure determination criteria by the lane departure determination means. The first lane departure suppression process using a warning sound and the second lane departure suppression process other than the first lane departure suppression process are started when it is determined that When it is determined based on the first lane departure criterion of the lane departure criterion that the vehicle is no longer in the lane departure danger state, the first lane departure suppression process is terminated, and The system is configured to end the second lane departure suppression process when it is determined that the vehicle is no longer in the lane departure danger state based on a second lane departure determination criterion having a lower degree of risk than one lane departure determination criterion. A lane departure suppression device characterized by the following.