JP7597003B2 - Lane Departure Prevention Device - Google Patents

Description

The present invention relates to a lane departure prevention device.

Lane departure prevention devices are known that perform lane departure prevention control to prevent the vehicle from departing from its lane (see, for example, Patent Document 1). There are also known lane departure prevention devices that set a line extending along a dividing line, such as a white line, that divides the lane in which the vehicle is traveling (the vehicle's lane) at a predetermined position based on the dividing line as a control start line for determining whether or not lane departure prevention control needs to be performed, and that start lane departure prevention control when the vehicle reaches the control start line.

JP 2018-100078 A

However, sometimes a structure of a certain height, such as a pole, is installed on the right-hand dividing line of the vehicle's lane, and in such cases the driver may drive the vehicle to the left to move away from the structure. When the vehicle is driving to the left in this way, the vehicle is more likely to reach the control start line (left-hand control start line) that is set based on the left-hand dividing line of the vehicle's lane, making it easier for lane departure prevention control to be executed.

However, since the driver is intentionally driving the vehicle to the left, if lane departure prevention control is executed just because the vehicle reaches the left control start line, lane departure prevention control will be executed unnecessarily.

As a measure to avoid unnecessary execution of lane departure prevention control, if a structure is installed on the right-hand dividing line of the vehicle's lane, the left-hand control start line can be shifted away from the vehicle, making it more difficult for the vehicle to reach the left-hand control start line even if the vehicle is traveling to the left.

However, for example, if the left control start line is shifted away from the vehicle when another vehicle is approaching the vehicle from the rear left, the vehicle may move further to the left, which may result in the other vehicle coming into contact with the vehicle, which is undesirable.

The object of the present invention is to provide a lane departure prevention device that can prevent an object on one side of the vehicle's lane from coming into contact with the vehicle when a structure is installed on the other side of the vehicle's lane, while avoiding unnecessary execution of lane departure prevention control.

The lane departure prevention device according to the present invention is equipped with a control device that executes lane departure prevention control to prevent the vehicle from departing from its lane.

The control device is configured to execute the lane departure prevention control when the host vehicle reaches a line that is set to extend along the dividing lines on both sides of the host lane, which is the lane in which the host vehicle is traveling, based on the dividing lines on both sides of the lane. The control device is also configured to set the line that is set along the dividing line on the other side of the host lane by shifting it in a direction away from the host vehicle when a structure is present on or near the dividing line on one side of the host lane . The control device is further configured to reduce the amount by which the line that is set along the dividing line on the other side of the host lane is shifted in a direction away from the host vehicle when a structure is present on or near the dividing line on one side and an object with which the host vehicle may come into contact is present beyond the dividing line on the other side, compared to when the object is not present.

According to the present invention, when a structure is present on or near a dividing line on one side of the host lane, a line used to determine whether or not lane departure prevention control is required and set along the dividing line on the other side of the host lane is shifted in a direction away from the host vehicle, and when an object with which the host vehicle may come into contact is present beyond the dividing line on the other side of the lane in which the host vehicle is traveling , the amount by which the line is shifted away from the host vehicle is smaller than when such an object is not present. Therefore, when a structure is installed on one side of the host lane, it is possible to prevent the host vehicle from coming into contact with an object on the other side of the host lane, while avoiding unnecessary execution of lane departure prevention control when the host vehicle travels close to the other side of the host lane.

The components of the present invention are not limited to the embodiments of the present invention described below with reference to the drawings. Other objects, other features and associated advantages of the present invention will be easily understood from the description of the embodiments of the present invention.

FIG. 1 is a diagram showing a lane departure prevention device according to an embodiment of the present invention and a vehicle (host vehicle) on which the device is mounted. FIG. 2 is a diagram showing a scene in which the host vehicle is traveling. FIG. 3 is a diagram showing a routine executed by the lane departure prevention device according to the embodiment of the present invention. FIG. 4A is a diagram showing a warning start line and a steering start line, and FIG. 4B is a diagram showing a warning start line distance and a steering start line distance. FIG. 5A is a diagram showing a scene where the host vehicle has reached the warning start line, and FIG. 5B is a diagram showing a scene where the host vehicle has reached the steering start line. FIG. 6 is a diagram showing a scene in which the vehicle is autonomously steered by operation control. FIG. 7 is a diagram showing a road on which a pole is installed as a structure on the right side of the vehicle. FIG. 8 is a diagram showing a road on which a guardrail is installed as a structure on the right side of the host vehicle. FIG. 9 is a diagram showing a scene in which another vehicle is approaching the host vehicle from the left rear of the host vehicle traveling on the road shown in FIG. FIG. 10 is a diagram showing a scene in which another vehicle is approaching the host vehicle from the left rear of the host vehicle traveling on the road shown in FIG. FIG. 11 is a diagram showing a routine executed by the lane departure prevention device according to the embodiment of the present invention. FIG. 12 is a diagram showing the structure distance and the structure height. FIG. 13 is a diagram showing the structure distance, the structure height, and the structure elevation angle. FIG. 14 is a diagram showing the warning start line and steering start line that are set in the scene shown in FIG. FIG. 15 is a diagram showing the warning start line and steering start line that are set in the scene shown in FIG. FIG. 16 is a diagram showing the warning start line and steering start line that are set in the scene shown in FIG. FIG. 17 is a diagram showing the warning start line and steering start line that are set in the scene shown in FIG.

The lane departure prevention device according to the embodiment of the present invention will be described below with reference to the drawings. As shown in FIG. 1, the lane departure prevention device 10 according to the embodiment of the present invention is mounted on the vehicle 100.

<ECU>
The lane departure prevention device 10 includes an ECU 90 as a control device. ECU is an abbreviation for Electronic Control Unit. The ECU 90 includes a microcomputer as a main part. The microcomputer includes a CPU, ROM, RAM, non-volatile memory, an interface, etc. The CPU is configured to realize various functions by executing instructions, programs, or routines stored in the ROM.

<Drive device, etc.>
In addition, the host vehicle 100 is equipped with a drive device 21, a braking device 22, and a steering device 23.

<Drive unit>
The drive device 21 is a device that outputs a drive torque (drive force) that is applied to the host vehicle 100 to make the host vehicle 100 travel, and is, for example, an internal combustion engine, a motor, etc. The drive device 21 is electrically connected to the ECU 90. The ECU 90 can control the operation of the drive device 21 to control the drive torque that is output from the drive device 21.

<Braking device>
The braking device 22 is a device that outputs a braking torque (braking force) that is applied to the host vehicle 100 in order to brake the host vehicle 100, and is, for example, a hydraulic brake device. The braking device 22 is electrically connected to the ECU 90. The ECU 90 can control the operation of the braking device 22 to control the braking torque output from the braking device 22.

<Steering device>
The steering device 23 is a device that outputs a steering torque (steering force) applied to the host vehicle 100 in order to steer the host vehicle 100, and is, for example, a power steering device. The steering device 23 is electrically connected to the ECU 90. The ECU 90 can control the operation of the steering device 23 to control the steering torque output from the steering device 23.

<Sensors, etc.>
Furthermore, the vehicle 100 is equipped with an accelerator pedal 31, an accelerator pedal operation amount sensor 32, a brake pedal 33, a brake pedal operation amount sensor 34, a steering wheel 35, a steering shaft 36, a steering angle sensor 37, a steering torque sensor 38, a vehicle speed detection device 50, a surrounding information detection device 60 and an alarm device 80.

<Accelerator pedal operation amount sensor>
The accelerator pedal operation amount sensor 32 is a sensor that detects the amount of operation of the accelerator pedal 31. The accelerator pedal operation amount sensor 32 is electrically connected to the ECU 90. The accelerator pedal operation amount sensor 32 transmits information on the detected amount of operation of the accelerator pedal 31 to the ECU 90. The ECU 90 obtains the amount of operation of the accelerator pedal 31 as an accelerator pedal operation amount AP based on that information.

The ECU 90 calculates the required drive torque (required drive force) based on the accelerator pedal operation amount AP and the traveling speed (vehicle speed) of the vehicle 100. The required drive torque is the drive torque that is required to be output by the drive device 21. The ECU 90 controls the operation of the drive device 21 so that the required drive torque is output.

<Brake pedal operation amount sensor>
The brake pedal operation amount sensor 34 is a sensor that detects the operation amount of the brake pedal 33. The brake pedal operation amount sensor 34 is electrically connected to the ECU 90. The brake pedal operation amount sensor 34 transmits information on the detected operation amount of the brake pedal 33 to the ECU 90. The ECU 90 obtains the operation amount of the brake pedal 33 as a brake pedal operation amount BP based on the information.

The ECU 90 calculates the required braking torque (required braking force) based on the brake pedal operation amount BP. The required braking torque is the braking torque that is required to be output by the braking device 22. The ECU 90 controls the operation of the braking device 22 so that the required braking torque is output.

<Steering angle sensor>
The steering angle sensor 37 is a sensor that detects the rotation angle of the steering shaft 36 with respect to the neutral position. The steering angle sensor 37 is electrically connected to the ECU 90. The steering angle sensor 37 transmits information on the detected rotation angle of the steering shaft 36 to the ECU 90. The ECU 90 obtains the rotation angle of the steering shaft 36 as the steering angle θ based on the information.

<Steering torque sensor>
The steering torque sensor 38 is a sensor that detects the torque input to the steering shaft 36 by the driver of the vehicle 100 via the steering wheel 35. The steering torque sensor 38 is electrically connected to the ECU 90. The steering torque sensor 38 transmits information on the detected torque to the ECU 90. The ECU 90 acquires the torque input to the steering shaft 36 by the driver via the steering wheel 35 (driver input torque TQd) based on the information.

<Vehicle speed detection device>
The vehicle speed detection device 50 is a device that detects the traveling speed (vehicle speed) of the host vehicle 100, and is, for example, a wheel speed sensor. The vehicle speed detection device 50 is electrically connected to the ECU 90. The vehicle speed detection device 50 transmits information on the detected vehicle speed of the host vehicle 100 to the ECU 90. The ECU 90 acquires the vehicle speed V of the host vehicle 100 based on the information.

The ECU 90 calculates the required steering torque based on the acquired steering angle θ, driver input torque TQd, and vehicle speed V. The required steering torque is the steering torque that is required to be output from the steering device 23. The ECU 90 controls the operation of the steering device 23 so that the required steering torque is output from the steering device 23, except when executing lane departure prevention control, which will be described later.

<Peripheral information detection device>
The surrounding information detection device 60 is a device that detects information about the surroundings of the vehicle 100, and in this example, includes an image sensor 61 and a radio wave sensor 62. The image sensor 61 is, for example, a camera. The radio wave sensor 62 is, for example, a radar sensor (such as a millimeter wave radar). The surrounding information detection device 60 may also include a sonic sensor such as an ultrasonic sensor (clearance sonar) or an optical sensor such as a laser radar (LiDAR).

<Image sensor>
The image sensor 61 is electrically connected to the ECU 90. The image sensor 61 captures an image of the periphery of the vehicle 100 and transmits information of the captured image to the ECU 90. The ECU 90 can obtain information (periphery detection information IS) about the periphery of the vehicle 100 based on the image information.

<Radio wave sensor>
The radio wave sensor 62 is electrically connected to the ECU 90. The radio wave sensor 62 transmits radio waves and receives radio waves (reflected waves) reflected by objects. The radio wave sensor 62 transmits information (detection results) related to the transmitted radio waves and received radio waves (reflected waves) to the ECU 90. In other words, the radio wave sensor 62 detects objects present in the vicinity of the vehicle 100 and transmits information (detection results) related to the detected objects to the ECU 90. The ECU 90 can obtain information (periphery detection information IS) related to objects such as structures present in the vicinity of the vehicle 100 based on the information (radio wave information).

<Alarm device>
The warning device 80 is a device for notifying the driver that there is a possibility that the vehicle 100 will deviate from the vehicle lane LN, and in this example, is equipped with a display device 81, an audio device 82, and a vibration device 83.

<Display Device>
The display device 81 is a device that displays images, and is, for example, a human-machine interface (HMI) such as a combination meter or a head-up display (HUD). The display device 81 is electrically connected to the ECU 90. The ECU 90 can cause the display device 81 to display various images.

<Audio Equipment>
The audio device 82 is a device that outputs voice such as an announcement or electronic sound such as a buzzer sound, and is, for example, a speaker or a buzzer. The audio device 82 is electrically connected to the ECU 90. The ECU 90 can cause the audio device 82 to output various voices or various electronic sounds.

<Vibration device>
The vibration device 83 is a device that applies vibration to the driver, and is, for example, a vibrator built into the steering wheel 35 or the driver's seat. The vibration device 83 is electrically connected to the ECU 90. The ECU 90 can apply vibration to the driver by activating the vibration device 83.

<Lane Departure Prevention System Operation>
Next, the operation of the lane departure prevention device 10 will be described. When the lane departure prevention device 10 determines that the host vehicle 100 is likely to deviate from the host lane LN while the host vehicle 100 is traveling as shown in Fig. 2, the lane departure prevention device 10 executes lane departure prevention control to prevent the host vehicle 100 from deviating from the host lane LN. In this example, the lane departure prevention control includes warning control and steering control.

The warning control is a control for issuing a warning to inform the driver of the vehicle 100 that the vehicle 100 may depart from the lane LN. In this example, the warning by the warning control is issued by at least one of displaying an image on the display device 81 and/or lighting a lamp on the display device 81 indicating that the vehicle 100 may depart from the lane LN, outputting a sound from the acoustic device 82 and/or outputting a buzzer sound from the acoustic device 82 indicating that the vehicle 100 may depart from the lane LN, and vibrating the steering wheel 35 and/or the driver's seat by the vibration device 83.

The steering control is a control that performs autonomous steering to autonomously steer the vehicle 100 and prevent the vehicle 100 from departing from the vehicle lane LN even without the driver's steering operation of the steering wheel 35.

These warning and steering controls will be described in more detail with reference to the flowchart shown in FIG. 3. The lane departure prevention device 10 executes the routine shown in FIG. 3 at a predetermined calculation cycle. Therefore, at a predetermined timing, the lane departure prevention device 10 starts processing from step 300 of the routine shown in FIG. 3, advances the processing to step 305, and acquires the warning start line distance DA and the steering start line distance DS.

As shown in FIG. 4A, the lane departure prevention device 10 sets an alarm start line LA used to determine whether or not to start alarm control (whether or not alarm control needs to be executed), and also sets a steering start line LS used to determine whether or not to start steering control (whether or not steering control needs to be executed).

The warning start line LA is the left warning start line LAL and the right warning start line LAR. The left warning start line LAL is a line that extends along the left edge of the vehicle's lane LN (e.g., the left dividing line 200L), and the right warning start line LAR is a line that extends along the right edge of the vehicle's lane LN (e.g., the right dividing line 200R). The warning start line LA shown in FIG. 4A is the left warning start line LAL.

The lane departure prevention device 10 acquires the left-side marking 200L and the right-side marking 200R based on the surrounding detection information IS.

In this example, a line spaced a predetermined distance inward from the edge (demarcation line 200) of the own lane LN is predefined as the reference alarm start line LAbase. More specifically, a line spaced a predetermined distance inward from the left edge (left demarcation line 200L) of the own lane LN is predefined as the reference left alarm start line LALbase, and a line spaced a predetermined distance inward from the right edge (right demarcation line 200R) of the own lane LN is predefined as the reference right alarm start line LARbase.

The lane departure prevention device 10 sets the warning start line LA based on the reference warning start line LAbase. More specifically, the lane departure prevention device 10 sets the left warning start line LAL based on the reference left warning start line LALbase, and sets the right warning start line LAR based on the reference right warning start line LARbase. The setting of the warning start line LA will be explained in detail later. The left warning start line LAL shown in FIG. 4A is obtained when the reference left warning start line LALbase is set as the left warning start line LAL as is.

The warning start line distance DA is the distance between the vehicle 100 and the warning start line LA, as shown in FIG. 4B. More specifically, the warning start line distance DA is the left warning start line distance DAL and the right warning start line distance DAR, where the left warning start line distance DAL is the distance between the left front end of the vehicle 100 and the left warning start line LAL, and the right warning start line distance DAR is the distance between the right front end of the vehicle 100 and the right warning start line LAR.

The steering start line LS is the left steering start line LSL and the right steering start line LSR. The left steering start line LSL is a line that extends along the left edge of the vehicle's lane LN (e.g., the left lane marking 200L), and the right steering start line LSR is a line that extends along the right edge of the vehicle's lane LN (e.g., the right lane marking 200R). The steering start line LS shown in FIG. 4A is the left steering start line LSL.

In this example, the line on the edge of the own lane LN (demarcation line 200) is predetermined as the reference steering start line LSbase. More specifically, the line on the left edge of the own lane LN (left demarcation line 200L) is predetermined as the reference left steering start line LSLbase, and the line on the right edge of the own lane LN (right demarcation line 200R) is predetermined as the reference right steering start line LSRbase.

The lane departure prevention device 10 sets the steering start line LS based on the reference steering start line LSbase. More specifically, the lane departure prevention device 10 sets the left steering start line LSL based on the reference left steering start line LSLbase, and sets the right steering start line LSR based on the reference right steering start line LSRbase. The setting of the steering start line LS will be explained in detail later. The left steering start line LSL shown in FIG. 4A is the left steering start line LSL when the reference left steering start line LSLbase is set as it is as the left steering start line LSL.

The steering start line distance DS is the distance between the vehicle 100 and the steering start line LS, as shown in FIG. 4B. More specifically, the steering start line distance DS is the left steering start line distance DSL and the right steering start line distance DSR, where the left steering start line distance DSL is the distance between the left front end of the vehicle 100 and the left steering start line LSL, and the right steering start line distance DSR is the distance between the right front end of the vehicle 100 and the right steering start line LSR.

The lane departure prevention device 10 then proceeds to step 310 to determine whether the warning start condition is met. The warning start condition is that the warning start line distance DA is equal to or less than zero. Therefore, as shown in FIG. 5A, when the vehicle 100 reaches the warning start line LA, the lane departure prevention device 10 determines that the warning start condition is met, and thereafter, determines that the warning start condition is met while the vehicle 100 is beyond the warning start line LA.

If the warning start condition is met, the lane departure prevention device 10 judges "Yes" in step 310, advances processing to step 315, and executes warning control. Next, the lane departure prevention device 10 advances processing to step 320 and judges whether the steering start condition is met. The steering start condition is that the steering start line distance DS is equal to or less than zero. Therefore, as shown in FIG. 5B, when the host vehicle 100 reaches the steering start line LS, the lane departure prevention device 10 judges that the steering start condition is met, and thereafter, judges that the steering start condition is met until the host vehicle 100 is returned to the host lane LN.

If the steering start condition is met, the lane departure prevention device 10 judges "Yes" in step 320, proceeds to step 325, and executes steering control. As a result, as shown in FIG. 6, the host vehicle 100 is steered autonomously and returned to the host lane LN. Next, the lane departure prevention device 10 proceeds to step 395, and temporarily ends the processing of this routine.

On the other hand, if the steering start condition is not satisfied, the lane departure prevention device 10 judges "No" in step 320 and proceeds to step 330. If steering control is being performed at that point, the lane departure prevention device 10 ends the steering control. Next, the lane departure prevention device 10 proceeds to step 395 and temporarily ends the processing of this routine.

If the warning start condition is not met, the lane departure prevention device 10 determines "No" in step 310, proceeds to step 335, and ends the warning control if warning control is being executed at that time. If the lane departure prevention device 10 is executing steering control at that time, it also ends the steering control. Next, the lane departure prevention device 10 proceeds to step 395, and ends the processing of this routine.

The lane departure prevention device 10 is configured to execute warning control when steering control is being performed, but may also be configured to terminate warning control when steering control is started.

<Setting the warning start line and steering start line>
Next, the setting of the warning start line LA and the steering start line LS will be described. As shown in Fig. 7, a structure 250 having a certain height, such as a pole, may be installed on the right-side dividing line 200R of the own lane LN, and in that case, the driver may drive the own vehicle 100 to the left so as to move away from the structure 250. Similarly, as shown in Fig. 8, a structure 250 having a certain height, such as a guardrail for dividing the central median strip, may be installed near the right side of the right-side dividing line 200R of the own lane LN, and in that case, the driver may drive the own vehicle 100 to the left so as to move away from the structure 250.

In this way, when the vehicle 100 is traveling to the left, if the reference left warning start line LALbase and the reference left steering start line LSLbase are set as the left warning start line LAL and the left steering start line LSL, respectively, the vehicle 100 is more likely to reach the left warning start line LAL and the left steering start line LSL, making it easier to execute lane departure prevention control.

However, since the vehicle 100 is traveling to the left due to the driver's intention, if lane departure control is executed just because the vehicle 100 reaches the left warning start line LAL or the left steering start line LSL in the situation shown in Figures 7 and 8, lane departure control will be executed unnecessarily.

As a measure to avoid unnecessary execution of lane departure prevention control, when a structure 250 of a certain height is installed on or near the right dividing line 200R of the own lane LN, a possible measure is to set the left warning start line LAL and the left steering start line LSL in a direction away from the own vehicle 100, so that even if the own vehicle 100 is traveling to the left, it is difficult to reach the left warning start line LAL and the left steering start line LSL.

In other words, to generalize to cases where a structure of a certain height is installed on or near the left dividing line 200L of the host lane LN, a possible measure to avoid unnecessary execution of lane departure prevention control is to set the warning start line LA and steering start line LS to the other side of the host lane LN and away from the host vehicle 100 when a structure of a certain height is installed on or near the left dividing line 200L of the host lane LN, thereby making it difficult for the host vehicle 100 to reach the warning start line LA and steering start line LS even if the host vehicle 100 travels close to the other side of the host lane LN.

However, for example, as shown in FIG. 9, if the left warning start line LAL and the left steering start line LSL are set in a direction away from the host vehicle 100 when another vehicle 150 is approaching the host vehicle 100 from the left rear, the host vehicle 100 may move further to the left, which may result in the host vehicle 100 coming into contact with the other vehicle 150, which is not preferable. Similarly, as shown in FIG. 10, if the warning start line LA and the steering start line LS are set in a direction away from the host vehicle 100 when another vehicle 150 traveling in the lane to the left of the host vehicle LN is approaching the host vehicle 100 from behind, the host vehicle 100 may move further to the left, which may result in the host vehicle 100 coming into contact with the other vehicle 150, which is not preferable.

In other words, to generalize to cases including cases where a structure of a certain height is installed on or near the left dividing line 200L of the host lane LN, if an object such as another vehicle 150 is approaching the host vehicle 100 from the rear on the other side of the host lane LN and the warning start line LA and steering start line LS are set on the other side of the host lane LN in a direction away from the host vehicle 100, there is a possibility that the object may come into contact with the host vehicle 100, which is not desirable.

The lane departure prevention device 10 is therefore configured to set an alarm start line LA and a steering start line LS so that, when a structure of a certain height is set on or near the dividing line 200 on one side of the host lane LN, the host vehicle 100 can be prevented from contacting an object on the other side of the host lane LN, while avoiding unnecessary execution of alarm control and operation control even if the host vehicle 100 travels close to the other side of the host lane LN.

Next, the setting of the warning start line LA and steering start line LS by the lane departure prevention device 10 will be explained with reference to the flowchart shown in FIG.

The lane departure prevention device 10 executes the routine shown in FIG. 11 at a predetermined calculation cycle. Therefore, at a predetermined timing, the lane departure prevention device 10 starts processing from step 1100 of the routine shown in FIG. 11, advances the processing to step 1105, and determines whether the structure condition is satisfied.

The structure condition is that the structure distance W is equal to or less than a predetermined distance (structure distance threshold Wth) and the structure height H is equal to or greater than a predetermined height (structure height threshold Hth), but it may also be that the structure distance W is equal to or less than the structure distance threshold Wth and the structure elevation angle θe is equal to or greater than a predetermined elevation angle (structure elevation angle threshold θe_th).

The structure distance W is the distance from the structure 250 to the own lane LN, and more specifically, the distance between the wall surface of the structure 250 on the own lane LN side and the end of the dividing line 200 on the structure 250 side. Therefore, as shown in FIG. 12, when the structure 250 is on the right side of the own lane LN, the structure distance W is the distance between the wall surface of the structure 250 on the own lane LN side and the right end ER of the right dividing line 200R, and when the structure 250 is on the left side of the own lane LN, the structure distance W is the distance between the wall surface of the structure 250 on the own lane LN side and the left end of the left dividing line 200L.

The structure height H is the height of the structure 250, and in this example, as shown in FIG. 12, is the height of the structure 250 from the road surface on which the vehicle 100 is traveling.

The structure elevation angle θe is the elevation angle of the upper end EU of the structure 250 from the vehicle lane LN. More specifically, when viewed on a vertical plane perpendicular to the traveling direction of the vehicle 100, it is the angle between a line along the road surface of the road on which the vehicle 100 is traveling and a line connecting the end of the demarcation line 200 on the structure 250 side on the structure 250 side and the upper end EU of the wall of the structure 250 on the road side on which the vehicle 100 is traveling. For example, in the example shown in FIG. 13, the structure elevation angle θe is the angle between a line L1 along the road surface of the road on which the vehicle 100 is traveling and a line L2 connecting the right end ER of the right demarcation line 200R and the upper end EU of the wall of the structure 250 on the road side on which the vehicle 100 is traveling. In this example, the structure elevation angle θe is obtained based on the structure distance W and the structure height H.

The lane departure prevention device 10 detects the structure 250 based on the surrounding detection information IS, and obtains the structure distance W, structure height H, and structure elevation angle θe based on the surrounding detection information IS.

If the structure condition is met, the lane departure prevention device 10 judges "Yes" in step 1105, advances the process to step 1110, and determines whether the opposite side attention condition is met.

The opposite side caution condition is a condition that an object with which the vehicle 100 may come into contact is present beyond the dividing line 200 on the opposite side of the vehicle 100 from the side on which the structure is set. The lane departure prevention device 10 detects the object based on the surrounding detection information IS.

If the opposite side attention condition is met, the lane departure prevention device 10 judges "Yes" in step 1110, proceeds to step 1115, and sets the offset amount ΔD to a relatively small predetermined amount (small offset amount ΔDsmall). Next, the lane departure prevention device 10 proceeds to step 1130, and sets the standard warning start line LAbase and the standard steering start line LSbase by the offset amount ΔD in a direction away from the vehicle 100 on the opposite side to the side on which the structure 250 is installed as the warning start line LA and the steering start line LS, respectively.

More specifically, when the lane departure prevention device 10 advances the process to step 1130, if the device is installed on or near the right dividing line 200R of the host lane LN, the device sets the reference left warning start line LALbase and the reference left steering start line LSLbase to the left of the host vehicle 100 by the offset amount ΔD as the left warning start line LAL and the left steering start line LSL, respectively. On the other hand, if the lane departure prevention device 10 is installed on or near the left dividing line 200L of the host lane LN, the device sets the reference right warning start line LARbase and the reference right steering start line LSRbase to the right of the host vehicle 100 by the offset amount ΔD as the right warning start line LAR and the right steering start line LSR, respectively.

Therefore, when the lane departure prevention device 10 advances processing from step 1115 to step 1130, it sets the standard warning start line LAbase and the standard steering start line LSbase as the warning start line LA and the steering start line LS, respectively, by shifting the standard warning start line LAbase and the standard steering start line LSbase by the small offset amount ΔDsmall in a direction away from the vehicle 100 on the side opposite the side on which the structure 250 is installed.

For example, as shown in FIG. 14, when a structure 250 (pole) is set on the right-side dividing line 200R of the vehicle's lane LN and the structure condition is satisfied, and another vehicle 150 is approaching the vehicle 100 from the left rear and the other side warning condition is satisfied, the lane departure prevention device 10 sets the reference left warning start line LALbase and the reference left steering start line LSLbase as lines shifted by a small offset amount ΔDsmall to the left of the vehicle 100 and away from the vehicle 100 as the left warning start line LAL and the left steering start line LSL, respectively.

Similarly, as shown in FIG. 15, when a structure 250 (guardrail) is set near the right side of the right dividing line 200R of the vehicle's lane LN and the structure condition is satisfied, and another vehicle 150 is approaching the vehicle 100 from the left rear of the vehicle 100 and the caution on the other side condition is satisfied, the lane departure prevention device 10 sets the reference left warning start line LALbase and the reference left steering start line LSLbase as lines shifted by a small offset amount ΔDsmall to the left of the vehicle 100 and away from the vehicle 100 as the left warning start line LAL and the left steering start line LSL, respectively.

After executing step 1130, the lane departure prevention device 10 advances to step 1195 and temporarily ends this routine.

On the other hand, if the opposite side attention condition is not satisfied, the lane departure prevention device 10 determines "No" in step 1110, proceeds to step 1120, and sets the offset amount ΔD to a relatively large predetermined amount, i.e., a predetermined amount (large offset amount ΔDlarge) larger than the small offset amount ΔDsmall. Next, the lane departure prevention device 10 proceeds to step 1130, and sets the standard warning start line LAbase and the standard steering start line LSbase as the warning start line LA and the steering start line LS, respectively, by the offset amount ΔD in a direction away from the vehicle 100 on the side opposite the side on which the structure is installed.

Therefore, when the lane departure prevention device 10 advances processing from step 1120 to step 1130, it sets the standard warning start line LAbase and the standard steering start line LSbase as the warning start line LA and the steering start line LS, respectively, by shifting the standard warning start line LAbase and the standard steering start line LSbase by the large offset amount ΔDlarge in a direction away from the vehicle 100 on the side opposite the side on which the structure 250 is installed.

For example, as shown in FIG. 16, if a structure 250 (pole) is set on the right-side dividing line 200R of the vehicle's lane LN, the structure condition is satisfied, and there is no object on the left side of the vehicle 100 that the vehicle 100 may come into contact with, and the opposite side caution condition is not satisfied, the lane departure prevention device 10 sets the reference left side warning start line LALbase and the reference left steering start line LSLbase shifted to the left by the large offset amount ΔDlarge in the direction away from the vehicle 100 as the left side warning start line LAL and the left side steering start line LSL, respectively.

Similarly, as shown in FIG. 17, if a structure 250 (guardrail) is set near the right side of the right dividing line 200R of the vehicle's lane LN and the structure condition is met, and there is no object on the left side of the vehicle 100 that the vehicle 100 may come into contact with, and the opposite side caution condition is not met, the lane departure prevention device 10 sets the reference left warning start line LALbase and the reference left steering start line LSLbase to the left by the large offset amount ΔDlarge in the direction away from the vehicle 100 as the left warning start line LAL and the left steering start line LSL, respectively.

After executing step 1130, the lane departure prevention device 10 advances to step 1195 and temporarily ends this routine.

Also, if the structure condition is not satisfied, the lane departure prevention device 10 judges "No" in step 1105, proceeds to step 1125, and sets the offset amount ΔD to zero. Next, the lane departure prevention device 10 proceeds to step 1130 and sets the warning start line LA and the steering start line LS, but at this time, the process has proceeded from step 1125 to step 1130, and the offset amount ΔD is zero. Therefore, the lane departure prevention device 10 sets the reference warning start line LAbase and the reference steering start line LSbase as the warning start line LA and the steering start line LS, respectively.

After executing step 1130, the lane departure prevention device 10 advances to step 1195 and temporarily ends this routine.

＜Effects＞
According to the lane departure prevention device 10, when a structure is installed on one side of the own lane LN, the warning start line LA and the steering start line LS are set to be shifted away from the own vehicle 100 to the other side of the own lane LN, and when an object with which the own vehicle 100 may come into contact exists beyond the dividing line 200 on the other side of the own lane LN, the amount by which the warning start line LA and the steering start line LS are shifted away from the own vehicle 100 to the other side of the own lane LN (offset amount ΔD) is smaller than when such an object does not exist. Therefore, when a structure is installed on one side of the own lane LN, it is possible to prevent the own vehicle 100 from coming into contact with an object existing on the other side of the own lane LN, while avoiding unnecessary execution of lane departure control when the own vehicle 100 travels close to the other side of the own lane LN.

The present invention is not limited to the above embodiment, and various modifications can be made within the scope of the present invention.

10... lane departure prevention device, 23... steering device, 60... surrounding information detection device, 61... image sensor, 62... radio wave sensor, 80... alarm device, 81... display device, 82... sound device, 83... vibration device, 90... ECU, 100... vehicle, 200... marking line, 250... structure

Claims (1)

A lane departure prevention device including a control device that executes lane departure prevention control for preventing a host vehicle from departing from a lane,
the control device is configured to execute the lane departure prevention control when the host vehicle reaches a line that is set to extend along a dividing line on each side of a host lane, the lane in which the host vehicle is traveling, using the dividing lines as references,
the control device is configured to, when a structure is present on or near the dividing line on one side that defines the host lane, shift the line that is set along the dividing line on the other side that defines the host lane in a direction away from the host vehicle,
the control device is configured to, when a structure is present on or near the dividing line on one side and an object with which the host vehicle may come into contact is present beyond the dividing line on the other side, reduce an amount by which the line set along the dividing line on the other side dividing the host lane is shifted in a direction away from the host vehicle, compared to a case in which the object is not present.
Lane departure prevention device.

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