Lane departure suppression controller, lane departure suppression control method and program

Abstract

To provide a lane departure suppression controller that can reduce the possibility of driver's anxiety even if lane departure suppression control is executed when an object exists on a side opposite to a lane departure direction of a vehicle.SOLUTION: A lane departure suppression controller executes lane departure suppression control for controlling a travel state of a vehicle in a cross direction so as to suppress that the vehicle departs from a travel area when such lane departure conditions are established that it is predicted that the vehicle departs from the travel area or that the vehicle departed from the travel area. The lane departure suppression controller further reduces magnitude of a lateral velocity of the vehicle in the lane departure suppression control in the case that suppression conditions including at least first condition such that an object exists on a side opposite to a side on which the vehicle departs from the travel area are established compared to the case that the suppression conditions are not established.SELECTED DRAWING: Figure 5

Description

[Technical Field]

[0001] The present invention relates to a departure prevention control device that performs departure prevention control to control the lateral driving state of a vehicle to prevent the vehicle from departing from a driving area when a departure condition is met in which the vehicle is predicted to deviate from a driving area or the vehicle has deviated from the driving area, a departure prevention control method in which a computer mounted on a vehicle performs departure prevention control, and a program that causes a computer mounted on a vehicle to perform departure prevention control. [Background technology]

[0002] Conventionally, there have been known departure suppression control devices that execute departure suppression control when a departure condition is met. For example, the departure suppression control device described in Patent Document 1 (hereinafter referred to as the "conventional device") executes departure suppression control in a first operation mode when the approach speed, which is the lateral speed at which the vehicle approaches the boundary of the vehicle's driving area (e.g., lane), is slow, and executes departure suppression control in a second operation mode when the approach speed is fast.

[0003] In the first operating mode, the vehicle is not decelerated, and in the second operating mode, the vehicle is decelerated. In both the first operating mode and the second operating mode, the steering motor is controlled so that the vehicle faces the center of the driving area. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Japanese Patent Application Publication No. 2017-197020 Summary of the Invention

[0005] In departure suppression control, the vehicle's traveling direction is changed from a departure direction, in which the vehicle deviates from the driving area, to a return direction, in which the vehicle returns to the driving area. If an object is present on the opposite side of the vehicle's departure direction, changing the vehicle's traveling direction to the return direction will cause the vehicle to travel toward the object. In this case, the driver may feel uneasy. Conventional devices do not take into account objects present on the opposite side of the vehicle's departure direction. This may cause the driver to feel uneasy.

[0006] The present invention has been made to address the above-mentioned problem, and aims to provide a departure prevention control device that can reduce the possibility of the driver feeling uneasy even when departure prevention control is executed when an object is present on the opposite side of the vehicle's departure direction.

[0007] When a departure condition is met in which it is predicted that the vehicle will deviate from the driving area or the vehicle has deviated from the driving area (step 310 "Yes"), the driving assistance device of the present invention (hereinafter referred to as "the device of the present invention") executes departure suppression control to control the lateral driving state of the vehicle so as to prevent the vehicle from deviating from the driving area (steps 500 to 595). The departure prevention control device is configured to reduce the magnitude of the vehicle's lateral speed in the departure prevention control (step 430) when a suppression condition is met (step 405 "Yes") that includes at least a first condition that an object is present on the side opposite to the side on which the vehicle departs from the driving area, compared to when the suppression condition is not met (step 405 "No").

[0008] According to the device of the present invention, the suppression condition is met when an object is present on the opposite side of the vehicle's departure from the driving area. When the suppression condition is met, the magnitude of the vehicle's lateral speed during departure suppression control is reduced compared to when the suppression condition is not met. This slows the speed at which the vehicle approaches the object, reducing the possibility of causing anxiety to the driver.

[0009] In one aspect of the device of the present invention, The departure suppression control device is If the vehicle reaches the return target position set within the boundary that defines the traveling area ("Yes" in step 325), the departure suppression control is terminated (step 330). a second condition (step 415) that the object is predicted to be present within a predetermined range of the vehicle that has reached the return target position on the assumption that the suppression condition is not satisfied, and if the first condition is satisfied, it is determined that the suppression condition is satisfied; It is structured as follows.

[0010] Even if an object that satisfies the first condition exists, if the second condition is not met (i.e., if the object is not present within a predetermined range of the vehicle that has reached the return target position), the vehicle is unlikely to come into contact with the object, and therefore the driver is unlikely to feel uneasy about the departure prevention control. Despite this low likelihood of the driver feeling uneasy about the departure prevention control, if the magnitude of the lateral speed of the departure prevention control becomes small, the driver is likely to feel bothered by the departure prevention control. Therefore, in this aspect, the prevention condition is not met unless the second condition is met.

[0011] In one aspect of the device of the present invention, The departure prevention control device is configured to, when the prevention condition is met, reduce the magnitude of the lateral velocity during the period (T2) from a change point (CP) where the vehicle's direction of travel is changed in the departure prevention control from a departure direction that deviates from the driving area to a return direction that returns to the driving area, until the vehicle reaches a return target position (RP) set inside the boundary that defines the driving area.

[0012] The driver is likely to feel uneasy when the vehicle is traveling toward an object that satisfies the first condition. In departure prevention control, the vehicle travels toward the departure direction immediately after starting departure prevention control, and then travels toward the return direction after the vehicle reaches the change point (i.e., the vehicle travels toward the object). In order to reduce the possibility that the driver will feel uneasy about departure prevention control, the magnitude of the lateral speed during the period from the change point until the vehicle reaches the return target position may be reduced. Note that the magnitude of the lateral speed during the period from the establishment of the departure condition until the vehicle reaches the change point is not reduced. This is because the lateral speed during this period is likely not to affect the driver's uneasiness, and extending this period would lengthen the period during which the vehicle deviates from the driving area.

[0013] In one aspect of the device of the present invention, The departure suppression control device is configured to determine that the suppression condition is satisfied when the first condition is satisfied and the third condition that the value obtained by subtracting the width of the vehicle from the width of the driving area is equal to or less than a predetermined first threshold value, or the fourth condition that the ratio of the vehicle's width to the width of the driving area is equal to or greater than a predetermined second threshold value is satisfied (step 420 "Yes").

[0014] When neither the third nor the fourth condition is met, the width of the driving area is relatively wide compared to the vehicle width. Therefore, even if the vehicle approaches an object that satisfies the first condition at the same lateral speed as when the suppression condition is not met, the driver is unlikely to feel uneasy. In such a case, if the magnitude of the vehicle's lateral speed during departure suppression control becomes small, the driver is likely to feel annoyed. For this reason, the suppression condition is met when the third or fourth condition is met.

[0015] In one aspect of the device of the present invention, The deviation suppression control device is configured to reduce the magnitude of the lateral velocity as the distance between the object and the boundary opposite the boundary from which the vehicle deviates becomes shorter, one of the left and right boundaries defining the driving area.

[0016] The shorter the distance, the closer the vehicle is to the object, which increases the driver's anxiety. According to this aspect, the magnitude of the lateral speed of the vehicle VA decreases according to the distance. This further reduces the possibility that the departure prevention control will cause anxiety to the driver.

[0017] In the departure prevention control method of the present invention, when a departure condition is met in which it is predicted that the vehicle will deviate from the driving area or the vehicle has deviated from the driving area (step 310 ``Yes''), a computer installed in the vehicle executes departure prevention control to control the lateral driving state of the vehicle so as to prevent the vehicle from deviating from the driving area (steps 500 to 595). The deviation suppression control method includes: a step (step 405) in which the computer determines whether a suppression condition including at least a first condition that an object is present on the side opposite to the side on which the vehicle departs from the traveling area is satisfied; The computer includes a step (step 430) of reducing the magnitude of the vehicle's lateral speed in the departure prevention control when the suppression condition is met (step 405 "Yes") compared to when the suppression condition is not met (step 405 "No").

[0018] When a departure condition is met in which it is predicted that the vehicle will deviate from the driving area or the vehicle has deviated from the driving area (step 310 "Yes"), the program of the present invention causes a computer installed in the vehicle to execute departure prevention control that controls the lateral driving state of the vehicle to prevent the vehicle from deviating from the driving area (steps 500 to 595). The program causes the computer to: a step of determining whether a suppression condition including at least a first condition that an object exists on the side opposite to the side on which the vehicle departs from the traveling area is satisfied (step 405); a step (step 430) of the computer reducing the magnitude of the lateral speed of the vehicle in the departure prevention control when the suppression condition is met (step 405 "Yes") compared to when the suppression condition is not met (step 405 "No"); Execute the following.

[0019] According to the deviation suppression control method and program of the present invention, the speed at which the vehicle approaches an object is slowed down, thereby reducing the possibility of causing anxiety to the driver.

[0020] In the above description, to facilitate understanding of the invention, the names and / or symbols used in the embodiments described below are enclosed in parentheses for the components of the invention corresponding to those embodiments. However, each component of the invention is not limited to the embodiments defined by the names and / or symbols. Other objects, features, and attendant advantages of the present invention will be easily understood from the following description of the embodiments of the present invention, which will be given with reference to the drawings. [Brief explanation of the drawings]

[0021] [Figure 1] 1 is a schematic configuration diagram of a departure suppression control device according to an embodiment of the present invention; [Figure 2] 3 is an explanatory diagram illustrating an example of operation of the departure prevention control device according to the embodiment of the present invention. FIG. [Figure 3] 2 is a flowchart of a start / end determination routine executed by a CPU of the ECU shown in FIG. 1. [Figure 4] 2 is a flowchart of a suppression condition determination subroutine executed by a CPU of the ECU shown in FIG. 1. [Figure 5] 2 is a flowchart of a departure suppression control routine executed by a CPU of the ECU shown in FIG. 1. DETAILED DESCRIPTION OF THE INVENTION

[0022] As shown in FIG. 1, the departure suppression control device according to this embodiment (hereinafter referred to as "the device 10") is applied to a vehicle VA, and includes the components shown in FIG.

[0023] The deviation prevention control ECU 20 is an ECU that executes deviation prevention control, which is a type of automatic driving and will be described later, and will be hereinafter referred to as "ECU 20."

[0024] In this specification, an "ECU" is an electronic control device that includes a microcomputer as its main component. The ECU is also called a control unit, a controller, or a computer. The microcomputer includes a CPU (processor), a ROM, a RAM, an interface (I / F), and the like. The functions of the ECU 20 may be realized by multiple ECUs.

[0025] The front camera 22 captures an image of the scenery in front of the vehicle VA to obtain image data. The front camera 22 transmits the image data to the ECU 20.

[0026] The millimeter-wave radar 24 transmits millimeter waves ahead of the vehicle VA and receives reflected waves from reflection points on the object, thereby acquiring radar object information. The radar object information includes the object's position relative to the vehicle VA and the object's relative velocity Vr relative to the vehicle VA. The millimeter-wave radar 24 transmits the radar object information to the ECU 20.

[0027] The vehicle speed sensor 26 detects the vehicle speed Vs that indicates the speed of the vehicle VA. The yaw rate sensor 28 detects the yaw rate Yr that acts on the vehicle VA. The steering angle sensor 30 detects the steering angle θ of the steered wheels of the vehicle VA. The ECU 20 acquires these detected values.

[0028] The steering motor 32 is incorporated into a steering mechanism 34. The steering mechanism 34 is a mechanism for steering the steered wheels in response to the operation of the steering wheel. In response to a command from the ECU 20, the steering motor 32 generates an assist torque in the steering mechanism 34 to assist the operation of the steering wheel, and generates an automatic steering torque in the steering mechanism 34 to change the steering angle θ of the steered wheels.

[0029] The departure suppression control will be described below with reference to FIG. The ECU 20 recognizes boundaries BL (right boundary RBL and left boundary LBL) that define (divide) the driving area TA in which the vehicle VA is traveling, based on the image data. Examples of the boundaries BL include white lines on the road, guardrails, curbs, and walls. The ECU 20 sets reference lines (right reference line Rth and left reference line Lth) at positions a predetermined distance away from the boundaries BL in a direction perpendicular to the boundaries BL.

[0030] When either of the following conditions 1 and 2 is met, the ECU 20 determines that the departure condition is met and executes departure suppression control. Condition 1: The predicted path PR of the vehicle VA intersects with the reference line (i.e., the vehicle VA is predicted to deviate from the reference line). Condition 2: The vehicle VA deviates from the reference line.

[0031] In the deviation suppression control, the ECU 20 obtains a target steering angle θtgt for suppressing deviation of the vehicle VA from a reference line from which the vehicle VA is likely to deviate (or has deviated) (i.e., for returning the vehicle VA to the traveling area TA). The ECU 20 controls the steering motor 32 so that the steering angle θ coincides with the target steering angle θtgt.

[0032] (Overview of operation) When a suppression condition is met that includes at least a condition (first condition) that an object (another vehicle VB shown in FIG. 2) is present on the opposite side (anti-departure side) from the departure side from which the vehicle VA departs, the ECU 20 reduces the magnitude of the lateral speed of the vehicle VA in the departure suppression control compared to when the suppression condition is not met. The lateral speed of the vehicle VA is the speed of the vehicle VA in the vehicle width direction.

[0033] This reduces the speed at which the vehicle VA approaches the object on the opposite side from the departure side, thereby reducing the possibility that the driver will feel uneasy about the departure suppression control.

[0034] (Activation) When the departure condition is met but the suppression condition is not met, the ECU 20 sets a normal driving route TR (see FIG. 2) along which the vehicle VA will travel under departure suppression control.

[0035] First, the ECU 20 determines the lateral positions of the change position CP and the target return position RP relative to the boundary BL based on the vehicle speed Vs, the position of the boundary BL relative to the vehicle VA, the shape of the traveling area TA, the departure lateral speed and the departure lateral acceleration. The change position CP is a position where the traveling direction of the vehicle VA changes from a departure direction (upward in the plane of FIG. 2) that deviates from the traveling area TA to a return direction (downward in the plane of FIG. 2) that returns to the traveling area TA. In other words, the change position CP is the position where the vehicle VA deviates the most. The target return position RP is a position located a predetermined distance inside the reference line. The departure lateral speed is the lateral speed of the vehicle VA when the departure condition is met. The departure lateral acceleration is the lateral acceleration of the vehicle VA when the departure condition is met.

[0036] Next, the ECU 20 determines the vertical positions of the changed position CP and the target return position RP relative to the boundary BL under the following constraints.

[0037] <Restrictions> Constraint 1: The lateral speed must be equal to or less than a preset upper limit lateral speed. Constraint 2: The lateral acceleration must be equal to or less than a preset upper limit of lateral acceleration. Constraint condition 3: A first time T1 required for the vehicle VA to reach the change position CP from the start position SP is equal to or shorter than a first threshold time T1th. The start position SP is the position of the vehicle VA when the departure condition is met. Constraint condition 4: A second time T2 required for the vehicle VA to reach the target return position RP from the changed position CP is equal to or less than a second threshold time T2th.

[0038] Next, the ECU 20 sets a route that passes through the change position CP and the target return position RP as the normal traveling route TR.

[0039] When the departure condition is met but the suppression condition is not met, the ECU 20 obtains a target steering angle θtgt for the vehicle VA to follow the normal driving route TR, and controls the steering motor 32 so that the steering angle θ becomes the target steering angle θtgt.

[0040] On the other hand, when the departure condition and the suppression condition are both met, the ECU 20 sets the suppressed travel route TR'. The setting of the suppressed travel route TR' is the same as the setting of the normal travel route TR, except that the following constraint condition 4' is used instead of the constraint condition 4. Constraint 4': The second time T2 is equal to or less than a "third threshold time T3th that is longer than the second threshold time T2th."

[0041] Therefore, when the suppression condition is satisfied, constraint condition 4', which is more relaxed than constraint condition 4, is used to set the suppressed travel route TR'. For this reason, when the suppression condition is satisfied, the second time T2 is longer than when the suppression condition is not satisfied. Therefore, when the suppression condition is satisfied, the magnitude of the lateral speed of the vehicle VA during the period from the change position CP to the target return position RP (second time T2) is smaller than when the suppression condition is not satisfied. This slows down the speed at which the vehicle VA approaches the object (other vehicle VB), thereby reducing the possibility that the departure suppression control will cause anxiety to the driver.

[0042] During the period (first time T1) from the start position SP to the change position CP, the vehicle VA travels in a direction away from the object (other vehicle VB), so the lateral speed of the vehicle VA during this period is unlikely to affect the driver's anxiety. Furthermore, if the lateral speed of the vehicle VA during this period were reduced, the time that the vehicle VA deviates from the traveling area TA would be lengthened. For this reason, in this embodiment, the same first time T1 is used whether the suppression condition is satisfied or not.

[0043] Next, the suppression conditions will be described in detail. The ECU 20 determines that the suppression conditions are met when the above-mentioned first condition and the following second and third conditions are all met. Second condition: On the assumption that the suppression condition is not satisfied (on the assumption that the vehicle VA has traveled the normal travel route TR), an object exists within a predetermined range AR of the vehicle VA that has reached the target return position RP. The predetermined range AR is set ahead of the vehicle VA. Third condition: The magnitude of the subtraction value (|WL−WV|) obtained by subtracting the width WV of the vehicle VA from the width WL of the traveling area TA is equal to or less than a threshold value Wth.

[0044] If the second condition is not met (i.e., if there is no object within the predetermined range AR of the vehicle VA that has reached the target return position RP on the normal driving route TR), the vehicle VA will not approach an object located on the non-departure side, and the driver is unlikely to feel uneasy. In such a case, if the lateral speed of the vehicle VA during departure prevention control becomes small, the driver is likely to feel annoyed. For this reason, the second condition is included in the suppression conditions.

[0045] If the third condition is not met, the width WL of the driving region TA is relatively wide compared to the vehicle width WV. Therefore, even if the vehicle approaches an object located on the non-departure side at the same lateral speed as when the suppression condition is not met, the driver is unlikely to feel uneasy. In such a case, if the lateral speed of the vehicle VA during departure suppression control becomes small, the driver is likely to feel annoyed. For this reason, the third condition is included in the suppression conditions.

[0046] (Specific operation) <Start / End Judgment Routine> The CPU of the ECU 20 executes the routine shown in the flowchart of FIG. 3 every time a predetermined time period elapses.

[0047] When an appropriate time arrives, the CPU starts the process from step 300 in Fig. 3, and the process proceeds to step 305. In step 305, the CPU determines whether the execution flag Xexe is "0".

[0048] The execution flag Xexe is set to "1" when departure prevention control is executed, and is set to "0" when departure prevention control is not executed. Furthermore, the execution flag Xexe is set to "0" in the initial routine. The initial routine is executed by the CPU when the ignition key switch (not shown) of the vehicle VA is changed from the OFF position to the ON position.

[0049] If the execution flag Xexe is "0", the CPU determines "Yes" in step 305, and the process proceeds to step 310. In step 310, the CPU determines whether or not a departure condition is met.

[0050] If the departure condition is not met, the CPU determines "No" in step 310, and the process proceeds to step 395, where the CPU temporarily ends this routine. On the other hand, if the departure condition is met, the CPU determines "Yes" in step 310, and executes steps 315 and 320.

[0051] Step 315: The CPU sets the execution flag Xexe to “1”. Step 320: The CPU executes a suppression condition determination subroutine. In the suppression condition determination subroutine, it is determined whether or not the suppression condition is met. The details of the suppression condition determination subroutine will be described later. Thereafter, the process proceeds to step 395, where the CPU temporarily ends this routine.

[0052] If the execution flag Xexe is "1" when the process proceeds to step 305, the CPU determines "No" in step 305, and the process proceeds to step 325. In step 325, the CPU determines whether the vehicle VA has reached the target return position RP.

[0053] If the vehicle VA has not yet reached the target return position RP, the CPU determines "No" in step 325, and the process proceeds to step 395, where the CPU temporarily ends this routine. On the other hand, if the vehicle VA has reached the target return position RP, the CPU determines "Yes" in step 325, and executes steps 330 and 335.

[0054] Step 330: The CPU sets the execution flag Xexe to “0”. Step 335: The CPU sets the suppression flag Xsup to “0”. The suppression flag Xsup is set to "1" when the suppression condition is met, and is set to "0" when the suppression condition is not met. Furthermore, the suppression flag Xsup is set to "0" in the initial routine. Thereafter, the process proceeds to step 395, where the CPU temporarily ends this routine.

[0055] <Suppression condition determination subroutine> When the process proceeds to step 320 in Fig. 3, the CPU starts the process from step 400 in Fig. 4, and the process proceeds to step 405. In step 405, the CPU determines whether or not an object is present on the side opposite to the departure side (i.e., determines whether or not the first condition is met).

[0056] If an object is present on the side opposite to the departure side, the CPU determines "Yes" in step 405 and executes steps 410 and 415. Step 410: The CPU sets a normal driving route TR. Step 415: The CPU determines whether the object is present within the predetermined range AR of the vehicle VA that has arrived at the target return position RP under the following conditions 1 and 2. In other words, in step 415, the CPU determines whether the second condition is met. Premise 1: The vehicle VA travels along the normal travel route TR and reaches the target return position RP. Assumption 2: The object continues to move in a direction estimated based on the object's position history.

[0057] If the object is present within the predetermined range AR of the vehicle VA that has arrived at the target return position RP, the CPU determines "Yes" in step 415, and the process proceeds to step 420. In step 420, the CPU determines whether the magnitude of the subtraction value (|WL-WV|) is equal to or less than the threshold value Wth (in other words, the CPU determines whether the third condition is met).

[0058] If the magnitude of the subtraction value (|WL−WV|) is equal to or smaller than the threshold value Wth, the CPU determines “Yes” in step 420 and executes steps 425 and 430 . Step 425: The CPU sets the suppression flag Xsup to “1”. Step 430: The CPU sets a suppressed travel route TR'. Thereafter, the process proceeds to step 495, where the CPU temporarily ends this routine, and the process proceeds to step 395 shown in FIG.

[0059] If no object is present on the side opposite to the departure side when the process proceeds to step 405, the CPU determines "No" in step 405, and the process proceeds to step 435. In step 435, the CPU sets the suppression flag Xsup to "0." Thereafter, the process proceeds to step 495, and the CPU temporarily ends this routine.

[0060] When the process proceeds to step 415, if the object is not present within the predetermined range AR of the vehicle VA that has arrived at the target return position RP, the CPU determines "No" in step 415 and the process proceeds to step 435.

[0061] When the process proceeds to step 420 , if the magnitude of the subtraction value (|WL−WV|) is greater than the threshold value Wth, the CPU determines “No” in step 420 and the process proceeds to step 435 .

[0062] <Departure suppression control routine> The CPU of the ECU 20 executes the routine shown in the flowchart of FIG. 5 every time a predetermined time period elapses.

[0063] When an appropriate time arrives, the CPU starts the process from step 500 in Fig. 5, and the process proceeds to step 505. In step 505, the CPU determines whether the execution flag Xexe is "1".

[0064] If the execution flag Xexe is "0", the CPU determines "No" in step 505, and the process proceeds to step 595, where the CPU temporarily ends this routine. If the execution flag Xexe is "1", the CPU determines "Yes" in step 505, and the process proceeds to step 510. In step 510, the CPU determines whether the suppression flag Xsup is "0".

[0065] If the suppression flag Xsup is “0”, the CPU determines “Yes” in step 510 and executes steps 515 and 520 . Step 515: The CPU obtains a target steering angle θtgt for the vehicle VA to travel along the normal travel route TR. Step 520: The CPU controls the steering motor 32 so that the steering angle θ coincides with the target steering angle θtgt. Thereafter, the process proceeds to step 595, where the CPU temporarily ends this routine.

[0066] If the suppression flag Xsup is "1", the CPU determines "No" in step 510, and the process proceeds to step 525. In step 525, the CPU acquires the target steering angle θtgt for the vehicle VA to travel along the suppressed travel route TR'. Thereafter, the process proceeds to step 520.

[0067] As a result, when the suppression condition is met, the magnitude of the lateral speed of the vehicle VA during departure prevention control is smaller than when the suppression condition is not met. This slows down the speed at which the vehicle approaches the object on the non-departure side, reducing the possibility that the departure prevention control will cause anxiety to the driver.

[0068] The present invention is not limited to the above-described embodiment and modifications, and various modifications can be adopted within the scope of the present invention.

[0069] (First Modification) When the suppression condition is met, the ECU 20 of the departure suppression control device 10 of this modified example may make the second time T2 longer (i.e., may make the magnitude of the lateral speed of the vehicle VA smaller) the shorter the distance WB (see Figure 2) between the object that satisfies the first condition of the suppression condition and the boundary BL on the opposite side of the boundary BL on the side from which the vehicle VA departs (hereinafter referred to as the ``opposite boundary BL'').

[0070] The shorter the distance WB, the closer the vehicle VA is to the object, which increases the driver's anxiety. According to this modification, the magnitude of the lateral speed of the vehicle VA decreases in accordance with the distance WB. This further reduces the possibility that the departure prevention control will cause anxiety to the driver.

[0071] (Second Modification) The ECU 20 of the departure suppression control device 10 according to this modification uses the following fourth condition in place of the third condition of the suppression conditions. Fourth condition: The ratio RT of the vehicle width WV to the width WL of the traveling area TA is equal to or greater than a threshold value Rth.

[0072] When the fourth condition is not met, the width WL is relatively wide compared to the vehicle width WV, and when the fourth condition is met, the width WL is relatively narrow compared to the vehicle width WV. For this reason, the fourth condition is used instead of the third condition.

[0073] (Third Modification) In the above embodiment, whether or not the suppression condition is satisfied is determined at the time when the departure condition is satisfied, but this is not limiting. In the deviation suppression control device 10 of this modified example, if the suppression condition is not satisfied at the time when the departure condition is satisfied, the ECU 20 of the deviation suppression control device 10 determines whether or not the suppression condition is satisfied after the time when the suppression condition is satisfied.

[0074] (Fourth Modification) In the above embodiment, when the suppression condition is met, the second time T2 is longer than when the suppression condition is not met, and the first time T1 remains unchanged whether the suppression condition is met or not. In this modified example, the ECU 20 of the departure suppression control device 10 may lengthen the first time T1 in addition to the second time T2 when the suppression condition is met.

[0075] Furthermore, when the suppression condition is satisfied, the magnitude of the upper limit lateral speed may be made smaller than when the suppression condition is not satisfied, rather than making the second time T2 longer than when the suppression condition is not satisfied.

[0076] The device 10 is applicable to vehicles such as internal combustion engine vehicles, hybrid vehicles, plug-in hybrid vehicles, fuel cell vehicles, and electric vehicles. The device 10 is also applicable to autonomous vehicles. The present invention can also be understood as a computer-readable non-transitory storage medium on which a program for realizing the functions of the device 10 is stored. [Explanation of symbols]

[0077] 10... departure suppression control device, 20... ECU, 22... forward radar, 24... millimeter wave radar, 32... steering motor

Claims

1. A departure suppression control device that executes departure suppression control to control a lateral traveling state of a vehicle so as to suppress departure of the vehicle from the traveling area when a departure condition is established that the vehicle is predicted to deviate from the traveling area or that the vehicle has deviated from the traveling area, The departure prevention control device is configured to, when a suppression condition including at least a first condition that an object is present on an opposite side to a side on which the vehicle departs from the traveling area is satisfied, reduce the magnitude of the lateral speed of the vehicle in the departure prevention control compared to when the suppression condition is not satisfied. Departure suppression control device.

2. 2. The departure suppression control device according to claim 1, The departure suppression control device is When the vehicle reaches a return target position set inside the boundary that defines the traveling area, the departure suppression control is terminated; a second condition that the object is predicted to be present within a predetermined range of the vehicle that has reached the return target position on the assumption that the suppression condition is not satisfied, and if the first condition is satisfied, it is determined that the suppression condition is satisfied. A deviation suppression control device configured as follows.

3. 2. The departure suppression control device according to claim 1, The departure prevention control device is configured to, when the prevention condition is satisfied, reduce the magnitude of the lateral speed during a period from a change point at which the traveling direction of the vehicle is changed in the departure prevention control from a departure direction in which the vehicle departs from the traveling area to a return direction in which the vehicle returns to the traveling area until the vehicle reaches a return target position set inside a boundary that defines the traveling area. Departure suppression control device.

4. 2. The departure suppression control device according to claim 1, The departure suppression control device is configured to determine that the suppression condition is satisfied when the first condition is satisfied and a third condition that a value obtained by subtracting the width of the vehicle from the width of the traveling area is equal to or smaller than a predetermined first threshold value, or a fourth condition that a ratio of the width of the vehicle to the width of the traveling area is equal to or larger than a predetermined second threshold value is satisfied. Departure suppression control device.

5. 2. The departure suppression control device according to claim 1, the departure suppression control device is configured to reduce the magnitude of the lateral speed as the distance between the object and one of left and right boundaries defining the traveling area, the boundary opposite to the boundary from which the vehicle departs, becomes shorter. Departure suppression control device.

6. A departure suppression control method in which, when a departure condition is established that a vehicle is predicted to deviate from a driving area or that the vehicle has deviated from the driving area, a computer mounted on the vehicle executes departure suppression control to control a lateral traveling state of the vehicle so as to suppress the vehicle from deviating from the driving area, The deviation suppression control method includes: a step of determining whether a suppression condition including at least a first condition that an object is present on an opposite side to a side on which the vehicle departs from the traveling area is satisfied; a step of the computer reducing a magnitude of a lateral speed of the vehicle during departure prevention control when the suppression condition is satisfied compared to a case where the suppression condition is not satisfied; A deviation suppression control method comprising:

7. A program that causes a computer mounted on a vehicle to execute departure suppression control that controls a lateral traveling state of the vehicle so as to suppress departure of the vehicle from the traveling area when a departure condition is established that the vehicle is predicted to deviate from the traveling area or that the vehicle has deviated from the traveling area, The program causes the computer to: determining whether a suppression condition including at least a first condition that an object is present on an opposite side to a side on which the vehicle departs from the traveling area is satisfied; a step of the computer reducing a magnitude of a lateral speed of the vehicle during departure prevention control when the suppression condition is satisfied compared to a case where the suppression condition is not satisfied; A program that executes.

Images