JP2004178158A - Lane departure prevention device - Google Patents

Abstract

An object of the present invention is to provide a lane departure prevention device that makes it difficult for a driver to lose track of a driving lane even when the driver does not intend to maintain the lane.
A lane marker detection area is determined based on a steering angle when a driver is performing steering to maintain a traveling lane. When the driver does not perform steering to maintain the traveling lane, the yaw angle φ of the own vehicle with respect to the traveling lane is set to the direction of the own vehicle with respect to the traveling lane, and the equivalent steering angle δ corresponding to the yaw angle φ with respect to the traveling lane. _A lane marker detection area is set based on _C.
[Selection] Fig. 2

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a lane departure prevention device that prevents a departure of a host vehicle when the vehicle is about to deviate from the lane during traveling.
[0002]
[Prior art]
Conventionally, as such a lane departure prevention device, for example, it is determined that the own vehicle is about to deviate from the traveling lane, and the driver can easily determine the lateral displacement of the traveling position of the own vehicle with respect to the reference position of the traveling lane. There is a vehicle that outputs a steering control torque sufficient to overcome the above problem by a steering actuator to prevent lane departure (for example, see Patent Document 1). Further, in such a lane departure prevention device, it is desired to always detect the lane. Therefore, there is a method in which, for example, a steering angle is set as a road parameter, and a lane marker model such as a white line is set from the road parameter (for example, see Patent Document 2).
[0003]
[Patent Document 1]
JP-A-11-96497 [Patent Document 2]
JP-A-11-296660
[Problems to be solved by the invention]
By the way, since the conventional lane departure prevention device requires a steering actuator, the braking force or the driving force of each wheel is controlled using, for example, an anti-skid control device or a driving force control device. It is conceivable to control the traveling direction or traveling position of the vehicle by generating a moment.
[0005]
However, the lane departure prevention device is configured by controlling the braking / driving force of each wheel as described above, and the driver does not perform the operation of maintaining the traveling lane, and the lane departure is controlled by the yaw moment by the braking / driving force control. In such a case, the driver may remain unaware of the fact that the control output is not easily transmitted to the steering wheel. And the steering angle become irrelevant, and as a result, the driver may lose track of the lane, that is, may lose.
[0006]
The present invention has been developed in view of these problems, and in preventing a lane departure due to a yaw moment, a lane in which the driver can easily keep track of the traveling lane even when the driver is not performing an operation to maintain the traveling lane. It is an object to provide a deviation prevention device.
[0007]
[Means for Solving the Problems]
In order to solve the above problems, the lane departure prevention device of the present invention detects the traveling lane of the own vehicle, and when it is detected that the own vehicle has a tendency to deviate from the traveling lane, Control the behavior of the vehicle such that a yaw moment is generated in a direction to avoid the deviation of the vehicle, and particularly when the driver is not performing an operation for maintaining the traveling lane, the own vehicle according to the direction of the own vehicle with respect to the traveling lane. Is detected.
[0008]
【The invention's effect】
According to the lane departure prevention device of the present invention, the traveling lane of the own vehicle is detected, and when it is detected that the own vehicle has a tendency to deviate from the traveling lane, the departure of the own vehicle from the traveling lane is detected. In addition to controlling the behavior of the vehicle so that a yaw moment is generated in the direction to avoid the vehicle, and detecting the traveling lane of the own vehicle according to the direction of the own vehicle with respect to the traveling lane, especially the driver maintains the traveling lane It is difficult to lose track of the driving lane even when the user does not perform the operation.
[0009]
BEST MODE FOR CARRYING OUT THE INVENTION
Hereinafter, a first embodiment of a lane departure prevention device according to the present invention will be described with reference to the accompanying drawings.
FIG. 1 is a schematic vehicle configuration diagram illustrating an example of a lane departure prevention device of the present embodiment. This vehicle is a rear-wheel drive vehicle equipped with an automatic transmission and a conventional differential gear, and the braking device is capable of independently controlling the braking force of the left and right wheels for both the front and rear wheels.
[0010]
In the drawing, reference numeral 1 denotes a brake pedal, 2 denotes a booster, 3 denotes a master cylinder, and 4 denotes a reservoir. Normally, the brake fluid pressure increased by the master cylinder 3 according to the amount of depression of the brake pedal 1 by the driver. The brake fluid pressure control circuit 7 is provided between the master cylinder 3 and each of the wheel cylinders 6FL to 6RR. In the brake fluid pressure control circuit 7, the brake fluid pressure of each of the wheel cylinders 6FL to 6RR can be individually controlled.
[0011]
The brake fluid pressure control circuit 7 utilizes a brake fluid pressure control circuit used for, for example, anti-skid control or traction control. In this embodiment, the brake fluid pressure of each of the wheel cylinders 6FL to 6RR is independently controlled. It is configured to be able to increase and decrease the pressure. The braking fluid pressure control circuit 7 controls the braking fluid pressure of each of the wheel cylinders 6FL to 6RR according to a braking fluid pressure command value from a braking / driving force control unit 8 described later.
[0012]
This vehicle controls the driving torque to the rear wheels 5RL and 5RR, which are driving wheels, by controlling the operating state of the engine 9, the selected gear ratio of the automatic transmission 10, and the throttle opening of the throttle valve 11. A driving torque control unit 12 is provided. The operation state control of the engine 9 can be controlled, for example, by controlling the fuel injection amount and the ignition timing, and can also be controlled by controlling the throttle opening at the same time. The drive torque control unit 12 can independently control the drive torque of the rear wheels 5RL and 5RR, which are the drive wheels. When input, the drive wheel torque is controlled with reference to the drive torque command value.
[0013]
Further, this vehicle is provided with a CCD camera 13 and a camera controller 14 as an external recognition sensor for detecting the position of the host vehicle in the driving lane for determining whether the host vehicle has departed from the driving lane. The camera controller 14 detects a lane marker such as a white line from a captured image in front of the host vehicle captured by the CCD camera 13 to detect a traveling lane, and also detects a yaw angle φ of the host vehicle with respect to the traveling lane, that is, a lane marker for the lane. The direction of the host vehicle, the lateral displacement X from the center of the traveling lane, the curvature β of the traveling lane, the traveling lane width L, and the like can be calculated. When the driving lane detection area is input from the braking / driving force control unit 8, the camera controller 14 detects the driving lane using the driving lane detection area for detecting a lane marker or the like as described later. Then, the data is calculated for the detected lane.
[0014]
The vehicle includes an acceleration sensor 15 for detecting a longitudinal acceleration Xg and a lateral acceleration Yg generated in the host vehicle, a yaw rate sensor 16 for detecting a yaw rate φ 'generated in the host vehicle, an output pressure of the master cylinder 3, a so-called output pressure. master cylinder pressure sensor 17, the depression amount of the accelerator pedal, namely an accelerator opening sensor 18 for detecting an accelerator opening Acc, a steering angle sensor 19 for detecting a steering angle δ of a steering wheel 21 for detecting the master cylinder pressure P _m, the rotational speed of the wheel 5FL-5RR, wheel speed sensors 22FL~22RR for detecting a so-called wheel speed _Vw i (i = _FL~RR), direction indicating switch 20 that detects a direction indicating operation by the direction indicator is provided, of which The detection signal is output to the braking / driving force control unit 8. Further, the yaw angle φ of the vehicle with respect to the traveling lane detected by the camera controller 14, the lateral displacement X from the center of the traveling lane, the curvature β of the traveling lane, the traveling lane width L, and the like are controlled by the drive torque control unit 12. The driving torque Tw is also output to the braking / driving force control unit 8 together. In addition, when the detected traveling state data of the vehicle has left-right directionality, the left direction is defined as the positive direction. That is, the yaw rate φ ′, the lateral acceleration Yg, the steering angle δ, and the yaw angle φ have positive values when turning left, and the lateral displacement X has a positive value when the vehicle is displaced leftward from the center of the traveling lane.
[0015]
Next, the logic of arithmetic processing performed by the braking / driving force control unit 8 will be described with reference to the flowchart of FIG. This arithmetic processing is performed, for example, for 10 msec. It is executed by a timer interrupt every predetermined sampling time ΔT. In this flowchart, no step for communication is provided, but information obtained by the arithmetic processing is updated and stored in the storage device as needed, and necessary information is read from the storage device as needed.
[0016]
In this calculation processing, first, in step S1, various data from the sensors, the controller, and the control unit are read. Specifically, the longitudinal acceleration Xg detected by each sensor, lateral acceleration Yg, yaw rate phi ', the wheel speed Vw _i, accelerator opening Acc, the master cylinder pressure P _m, the steering angle [delta], direction indicating switch signal, Further, the driving torque Tw from the driving torque control unit 12 is read. Further, in the step S1, combined, among the wheel speeds Vw _i'm read, before a non-driven wheel left and right wheel speeds Vw _FL, calculates the traveling velocity V of the vehicle from an average value of Vw _FR. At this time, the yaw angle φ of the own vehicle with respect to the travel lane, the lateral displacement X from the center of the travel lane, the curvature β of the travel lane, and the travel lane width L from the camera controller 14 have not been read yet.
[0017]
Next, the process proceeds to step S2, where it is determined whether or not a lane keeping non-operation flag F, which will be described later, is set to "1", and if the lane keeping non-operation flag F is set to "1". In step S3, the process proceeds to step S3. Otherwise, the process proceeds to step S4.
In step S3, a travel lane detection area, which will be described later, is set based on the steering angle δ read in step S1, using a method described in, for example, JP-A-11-296660, and then the process proceeds to step S5. I do.
[0018]
In step S4, the direction of the host vehicle with respect to the travel lane calculated in step S5 described later, that is, the yaw angle φ of the host vehicle with respect to the travel lane (hereinafter, also referred to as yaw angle φ with respect to the lane) in the previous calculation processing. and calculating the equivalent steering angle [delta] _C, using the pair lane yaw angle equivalent steering angle [delta] _C, the process proceeds to step S5 after setting the same traveling lane detection area as in step S3. Incidentally, versus lane yaw angle equivalent steering angle [delta] _C is obtained by multiplying the steering gear ratio to said pair lane yaw angle phi.
[0019]
In step S5, the traveling lane in which the host vehicle is traveling is detected based on the traveling lane detection area set in step S3 or step S4, for example, using the method described in Japanese Patent Application Laid-Open No. H11-296660. To calculate the yaw angle φ of the own vehicle with respect to the traveling lane, the lateral displacement X from the center of the traveling lane, the curvature β of the traveling lane, and the traveling lane width L. Read.
[0020]
Next, the process proceeds to step S6, where it is determined whether or not the traveling lane has been detected in step S5. If the traveling lane has been detected, the process proceeds to step S7, and if not, the process proceeds to step S8. I do.
In step S7, the yaw angle φ of the host vehicle calculated in step S5 is updated and stored, and then the process proceeds to step S11.
[0021]
In step S11, the steering state of the driver (the driver in the figure) is determined, and then the process proceeds to step S12. The driver's steering state is, for example, a steering angular velocity or a previously calculated value of a departure estimated value described later. In the next step S12, it is necessary to determine whether the driver is performing steering to maintain the traveling lane. It shows a proper steering state.
In step S12, it is determined whether or not the driver is performing steering to maintain the traveling lane. If the driver is performing lane keeping steering, the process proceeds to step S10, and if not, the process proceeds to step S13. . The determination of the steering to maintain the traveling lane may be, for example, that the lane departure prevention control according to the present embodiment is not operating or a lane departure estimated value to be described later is equal to or smaller than a threshold smaller than the lane departure determination threshold. When the value is equal to or less than the threshold value for determining that the vehicle is tending, it can be determined that steering while maintaining the lane is being performed.
[0022]
In step S13, the lane keeping non-operation flag F is set to "1", and the process proceeds to step S14.
In step S10, the lane keeping non-operation flag F is reset to "0", and the process proceeds to step S14.
In step S14, a future estimated lateral displacement XS is calculated as a departure estimated value, and then the process proceeds to step S15. Specifically, the yaw angle φ of the own vehicle relative to the travel lane read in step S5, the lateral displacement X from the center of the travel lane, the curvature β of the travel lane, and the travel speed V of the own vehicle calculated in step S1 are calculated. Then, a future estimated lateral displacement XS is calculated according to the following two equations.
[0023]
XS = Tt × V × (φ + Tt × V × β) + X (2)
Here, Tt is a headway time for calculating a front gaze distance, and when the headway time Tt is multiplied by the traveling speed V of the own vehicle, it becomes a front gaze distance. That is, the estimated lateral displacement from the center of the traveling lane after the headway time Tt is the estimated future lateral displacement XS. As will be described later, in the present embodiment, when the future estimated lateral displacement XS is equal to or greater than a predetermined lateral displacement limit value, it is determined that the host vehicle may deviate from the traveling lane or is likely to deviate. It is.
[0024]
In step S15, it is determined whether or not the host vehicle has a tendency to deviate from the traveling lane, and then the process proceeds to step S16. Specifically, the absolute value of future estimated lateral displacement as the deviation estimated value calculated at the step S14 | XS | is, the departure tendency own vehicle from the traveling lane when the at lateral displacement limit value X _C or higher If there is, the departure determination flag _FLD is set, and if not, the own vehicle has no tendency to deviate from the traveling lane, and the departure determination flag _FLD is reset. When the lane change direction estimated from the input from the direction indicating switch 20 matches the departure direction of the host vehicle from the travel lane, the departure determination flag _FLD is reset. Further, in this step S15, it may be determined whether or not to warn that the host vehicle is deviating from the traveling lane. Specifically, the absolute value | XS | of the future estimated lateral displacement as the departure estimated value calculated in step S14 is calculated from the half value of the traveling lane width L read in step S5 to the vehicle width L of the host vehicle. and to alarm when ₀ half value is the lateral displacement limit value X _C or minus, techniques such as shall not alarm is considered otherwise.
[0025]
On the other hand, in step S8, the lane keeping non-operation flag F is reset to "0", and the process proceeds to step S16.
In the step S16, sets calculates a target yaw moment M _S for lane departure prevention. Here, since only sets a target yaw moment M _S when the departure determination flag F _LD is set, when the departure determination flag F _LD is set, a proportional coefficient K ₁ determined by the vehicle specification using the proportional coefficient K ₂ is set according to the vehicle running speed V as shown in FIG. 3, and future estimated lateral displacement XS calculated at step S14, and the lateral displacement limit value X _C, below 3 to calculate the target yaw moment M _S according to the formula.
[0026]
M _S = −K ₁ × K ₂ × (XS−X _C ) (3)
The target yaw moment M _S when said deviation determination flag F _LD is in the reset state to "0".
Next, the process proceeds to step S17 to calculate the target braking fluid pressure P _{Si for} each wheel and the target driving force of the driving wheel. Specifically, with respect to the master cylinder pressure P _m read in step S1, when the wheel master cylinder pressure after based on front-rear braking force distribution and P _mR, the departure determination flag F _LD is in the reset state sometimes, the left and right front wheels 5FL, 5FR wheel cylinders 6FL, target brake fluid pressure _P SFL to _{6FR, P SFR} both the master cylinder pressure _{P m,} and the rear left and right wheels 5RL, 5RR wheel cylinders 6RL, target brake to 6RR fluid pressure _{P SRL, P SRR} becomes the rear wheel master cylinder pressure _{P mR} together.
[0027]
On the other hand, even when the departure determination flag F _LD is set, performs case analysis in accordance with the magnitude of the target yaw moment M _S calculated in step S16. That is, when the absolute value | M _S | of the target yaw moment is less than the predetermined value M _S0 , a difference is generated only in the braking force of the rear left and right wheels, and the absolute value | M _S | of the target yaw moment becomes the predetermined value M _S When it is _{equal to} or greater than _S0 , a difference is generated between the braking forces of the front, rear, left and right wheels. Therefore, when the absolute value | M _S | of the target yaw moment is less than the predetermined value M _S0 , the front left and right wheel target braking fluid pressure difference ΔP _SF is “0”, and the rear left and right wheel target braking fluid pressure difference ΔP _SR is It is given by Equation 4. Similarly, the absolute value of the target yaw moment | M S _| is below Equation 5 is left and right front wheel target brake hydraulic pressure difference [Delta] P _SF when the predetermined value M _S0 or more, the rear left and right wheel target braking fluid pressure difference [Delta] P _SR is below 6 Given by the formula. Incidentally, T in the formulas (the same in the front and rear wheels) tread, K _bF, K _bR, respectively, a conversion coefficient for converting the braking force into brake hydraulic pressure, determined by the brake specifications.
[0028]
ΔP _SR = 2 × K _bR × | M _S | / T (4)
ΔP _SF = 2 × K _bF × (| M _S | −M _S0 ) / T (5)
ΔP _SR = 2 × K _bR × | M _S0 | / T (6)
Therefore, when the target yaw moment M _S is negative value, that is, the target brake fluid pressure P _Si of each wheel cylinder 6FL~6RR when the host vehicle is about to lane departure to the left is given by the following Equation 7 .
[0029]
_{P SFL} = P _m
P _SFR = P _m + ΔP _SF
P _SRL = P _m
P _SRR = P _m + ΔP _SR (7)
In contrast, when the target yaw moment M _S is positive, i.e. the vehicle is at the target brake fluid pressure P _Si is Formula 8 below for each wheel cylinder 6FL~6RR when trying to lane departure to the right Given.
[0030]
P _SFL = P _m + ΔP _SF
P _SFR = P _m
P _SRL = P _m + ΔP _SR
P _SRR = P _m (8)
In the present embodiment, the departure determination flag _FLD is set, and when the lane departure prevention control is performed, the engine output is throttled to disable acceleration even when the accelerator operation is performed. Accordingly, the target driving torque Trq _DS when divergence determination flag F _LD is set, the value corresponding to the accelerator opening Acc is loaded in step S1, the target brake hydraulic pressure difference [Delta] P _SF of the front and rear _wheels, [Delta] P A value corresponding to the sum of _SRs is subtracted. That is, the value corresponding to the accelerator opening Acc is a driving torque for accelerating the host vehicle according to the accelerator opening Acc, and a value corresponding to the sum of the target braking fluid pressure differences ΔP _SF and ΔP _SR of the front and rear wheels. Is a braking torque generated by the sum of the target braking fluid pressure differences ΔP _SF and ΔP _SR . Therefore, when the departure determination flag _FLD is set and the lane departure prevention control is performed, the engine torque is reduced by the braking torque generated by the sum of the target braking fluid pressure differences ΔP _SF and ΔP _SR. Become. The target driving torque Trq _DS when divergence determination flag F _LD is reset, the only driving torque amount for accelerating the vehicle in accordance with the accelerator opening Acc.
[0031]
Next, the process proceeds to step S18, in which the target brake fluid pressure of each wheel calculated in step S17 is output to the brake fluid pressure control circuit 7, and the target drive torque of the drive wheel is determined by the drive torque control unit. Then, the process returns to step S12 and the program returns to the main program.
According to this processing, no intentional traffic lane change of the driver, and when the estimated future lateral displacement XS becomes lateral displacement limit value X _C or higher, the vehicle tends to deviate from the driving lane is set departure determination flag F _LD is determined that the calculated target yaw moment M _S on the basis of the difference between future estimated lateral displacement XS and lateral displacement limit value X _C, attained its target yaw moment M _S Thus, the braking force of each wheel is controlled. Thus, for example, when the steering input is small, a yaw moment for preventing the lane departure is generated in the vehicle, the lane departure is prevented, and the traveling speed of the vehicle is reduced by the braking force. Can be prevented. Further, in this embodiment, while the lane departure prevention control is being performed, the output torque of the engine is reduced and the traveling speed of the host vehicle is reduced, so that it is possible to further safely prevent the lane departure. It becomes.
[0032]
In this embodiment, the travel lane detection area is set according to the operation state of the departure prevention control when the travel lane is lost as described above. The traveling lane detection area is for detecting a lane marker such as a white line from an image captured by the CCD camera 13 as shown in FIG. Specifically, detecting (scanning) a lane marker in the entire captured image requires a large calculation load and takes time. Therefore, a smaller detection area (a so-called window) is set in an area where a lane marker is likely to exist, and the lane marker is detected in the detection area. Generally, when the direction of the own vehicle with respect to the lane changes, the position of the lane marker projected in the image also changes. For example, in Japanese Patent Application Laid-Open No. H11-296660, the direction of the own vehicle with respect to the lane is estimated from the steering angle δ. The detection area is set in the area where the lane marker will be projected.
[0033]
On the other hand, as shown in FIG. 5, for example, when there is no steering input (the front wheel is not steered) and the vehicle attempts to deviate to the right from the traveling lane, the braking force applied to the front left wheel by the departure prevention control is controlled. illustrated counterclockwise by, i.e. the target yaw moment M _S is generated in the leftward turning direction. In such a case, the steering angle δ does not accurately represent the direction of the host vehicle with respect to the traveling lane. That is, as described in JP-A-11-296660, if the travel lane detection area is set only in accordance with the steering angle δ, it becomes rather difficult to detect the travel lane such as a lane marker. Therefore, in the present embodiment, when there is no steering input by the driver and the vehicle is likely to depart from the lane, that is, when the driver does not intend to maintain the lane, the lane keeping non-operation flag F is set, and setting the travel lane detection area using [delta] _C the pair lane yaw angle equivalent steering angle in the case. That, or follow the preceding vehicle, when or automatic steering along the driving lane, of course, the target yaw moment M _S and the steering input, comprehensively considering yaw angle or the like of the vehicle with respect to the traffic lane When the driver does not intend to maintain the driving lane, only when the driver does not intend to keep the driving lane, the driving lane detection is performed based on the yaw angle φ of the own vehicle with respect to the driving lane. It is more important to set the area so that you can keep track of the driving lane as much as possible. In the present embodiment, even in such a situation, it is possible to obtain an effect that the traveling lane is not easily lost.
[0034]
As described above, the sensors and the camera controller 14 of FIG. 1 and the steps S1 and S5 of the arithmetic processing of FIG. 2 constitute the traveling state detecting means of the present invention, and similarly, the steps S3 to S3 of the arithmetic processing of FIG. S8 and steps S10 to S13 constitute the traveling lane detecting means, steps S14 and S15 of the arithmetic processing of FIG. 2 constitute the departure determining means, and steps S16 to S18 of the arithmetic processing of FIG. The braking fluid pressure control circuit 7 and the drive torque control unit 12 constitute a vehicle behavior control means, step S17 of the arithmetic processing of FIG. 2 constitutes a braking / driving force control amount calculating means, and steps S18 and S18 of the arithmetic processing of FIG. The braking fluid pressure control circuit 7 and the drive torque control unit 12 of FIG. 1 constitute braking / driving force control means.
[0035]
Next, a second embodiment of the lane departure prevention device of the present invention will be described. The schematic configuration of the vehicle in this embodiment is the same as that in FIG. 1 of the first embodiment.
In the present embodiment, the arithmetic processing performed by the braking / driving force control unit 8 is changed from that of FIG. 2 of the first embodiment to that of FIG. The arithmetic processing in FIG. 7 is similar to the arithmetic processing in FIG. 2 and has the same steps. Therefore, the same reference numerals are given to the same steps, and the detailed description is omitted. To give a specific difference, step S9 is interposed between step S7 and step S11.
[0036]
In the step S9, it is determined whether or not the steering angular velocity composed of the differential value of the steering angle δ read in the step S1 is equal to or more than a predetermined value. If the steering angular velocity is equal to or more than the predetermined value, the process proceeds to the step S10. The process proceeds to step S11 if not.
According to this calculation processing, in addition to the operation of the first embodiment, when it is determined that the steering angular velocity is equal to or more than a predetermined value, that is, when it is determined that the driver has intentionally input steering, the lane keeping non-operation flag F is set. If the reset is not performed, the lane keeping steering judgment of the driver in step S12 is performed. Therefore, the lane keeping operation by the driver can be detected more reliably, and the traveling lane is not easily lost by that much.
[0037]
As described above, the sensors and the camera controller 14 of FIG. 1 and the steps S1 and S5 of the arithmetic processing of FIG. 6 constitute the traveling state detecting means of the present invention. Similarly, the steps S3 to S3 of the arithmetic processing of FIG. S13 constitutes the traffic lane detecting means, step S14 and step S15 of the calculation processing of FIG. 6 constitute the departure determination means, and steps S16 to S18 of the calculation processing of FIG. 6 and the brake fluid pressure control circuit 7 of FIG. The drive torque control unit 12 and the driving torque control unit 12 constitute a vehicle behavior control means. Step S17 of the calculation processing in FIG. 6 constitutes a braking / driving force control amount calculation means. Step S18 of the calculation processing in FIG. The control circuit 7 and the driving torque control unit 12 constitute braking / driving force control means.
[0038]
In the above embodiment has calculated lateral displacement limit value X _C as the threshold value of the lane departure determination from the vehicle width and the running lane width, for example, the traffic lane width in Japan highway determined with 3.35m Therefore, for example, this may be fixed to 0.8 m.
[Brief description of the drawings]
FIG. 1 is a schematic configuration diagram showing an example of a vehicle equipped with a lane departure prevention device of the present invention.
FIG. 2 is a flowchart illustrating a first embodiment of an information calculation process executed in the braking / driving force control unit of FIG. 1;
FIG. 3 is a control map used for the calculation processing of FIG. 2;
FIG. 4 is an explanatory diagram of the operation of the arithmetic processing of FIG. 2;
FIG. 5 is an explanatory diagram of the operation of the arithmetic processing in FIG. 2;
FIG. 6 is a flowchart showing a second embodiment of the information calculation process executed in the braking / driving force control unit of FIG. 1;
[Explanation of symbols]
6FL to 6RR are wheel cylinders 7 are braking fluid pressure control circuits 8 are braking / driving force control units 9 are engines 12 are driving torque control units 13 are CCD cameras 14 are camera controllers 15 are acceleration sensors 16 are yaw rate sensors 17 are master cylinder pressures Sensor 18 is an accelerator opening sensor 19 is a steering angle sensor 20 is a direction indicating switch 22FL-22RR is a wheel speed sensor

Claims (5)

Traveling lane detecting means for detecting the traveling lane of the own vehicle, traveling state detecting means for detecting the traveling state of the own vehicle, traveling lane detected by the traveling lane detecting means and traveling state detected by the traveling state detecting means Departure determining means for detecting that the own vehicle is deviating from the traveling lane, and detecting by the traveling state detecting means when the departure determining means detects that the own vehicle is deviating from the traveling lane. Vehicle behavior control means for controlling the behavior of the vehicle such that a yaw moment is generated in a direction to avoid the departure of the own vehicle from the traveling lane according to the traveling state, wherein the traveling lane detecting means comprises: The traveling lane of the own vehicle is detected in accordance with the direction of the own vehicle with respect to the traveling lane detected based on the traveling lane detected by the traveling lane detecting means and the traveling state detected by the traveling state detecting means. Lane departure prevention apparatus characterized by. The driving lane detecting means detects a driving lane of the host vehicle according to a direction of the host vehicle with respect to the driving lane when the driver is not performing an operation for maintaining the driving lane. 4. The lane departure prevention device according to claim 1. The lane departure prevention device according to claim 1 or 2, wherein the traveling lane detecting means detects a traveling lane of the own vehicle according to an orientation of the own vehicle with respect to the traveling lane when a steering input is small. . The traveling lane detecting means sets a traveling lane detection area according to the direction of the own vehicle with respect to the traveling lane, and detects the traveling lane of the own vehicle based on the traveling lane detection area. The lane departure prevention device according to any one of claims 1 to 3. The vehicle behavior control unit includes a braking / driving force control amount calculating unit that calculates a braking / driving force control amount of each wheel such that a yaw moment is generated in a direction to avoid departure of the host vehicle from the traveling lane. 5. A braking / driving force control means for controlling the braking / driving force of each wheel according to the braking / driving force control amount calculated by the driving force control amount calculating means. The lane departure prevention device as described.

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