Vehicle notification control device

Abstract

A vehicle notification control device balances the need to execute notification control earlier than automatic braking control during a turn and to suppress unnecessary operation of the control. The device determines, based on surrounding information and the operating state of an operator, whether a vehicle is likely to turn in a specific direction when an oncoming vehicle is approaching. If the determination is positive, the device determines, based on vehicle information including at least one of a steering input value or the presence or absence of a brake operation and the vehicle speed, whether the vehicle is likely to complete crossing the oncoming lane or intersection after a reference time has elapsed. If the determination is positive, the device executes notification control when a hypothetical meeting time required for the vehicle to hypothetically meet the oncoming vehicle is greater than a lower limit time and less than an upper limit time (a time below the reference time), assuming that the vehicle is moving in the longitudinal direction, i.e., the direction opposite to the oncoming vehicle's movement, at a longitudinal velocity that is the longitudinal component of the vehicle speed, and that the oncoming vehicle maintains its current movement state.

Description

Technical Field

[0001] The present invention relates to a notification control device for a vehicle that notifies a driver of the own vehicle of the presence of an oncoming vehicle when there is a possibility of collision with the oncoming vehicle while the own vehicle is turning. Background Art

[0002] Conventionally, there are known devices (hereinafter referred to as "conventional devices") that, upon detecting another vehicle with the potential for collision with the vehicle itself, perform collision avoidance control to avoid collision with the other vehicle and mitigate the impact of the collision. Examples of collision avoidance control include warning control that issues a warning to the driver of the vehicle itself and automatic braking control that automatically applies braking force to the vehicle itself. Hereinafter, the "possibility of a collision between the vehicle itself and the other vehicle" will also be referred to as "collision possibility."

[0003] Conventional devices determine the likelihood of a collision based on the predicted trajectory of the own vehicle and the predicted trajectory of another vehicle. Specifically, conventional devices calculate the own vehicle's turning radius based on the speed and yaw rate of the own vehicle, calculate the predicted trajectory of the own vehicle based on this turning radius, and calculate the predicted trajectory of the other vehicle based on the changes in the position of the other vehicle. When the predicted trajectories of the two vehicles intersect, the conventional device determines whether a collision would occur if the own vehicle and the other vehicle maintained their current movement states (i.e., whether the timing of the own vehicle and the other vehicle's respective predicted trajectories reaching the intersection point is approximately the same). If it is determined that the own vehicle and the other vehicle will collide (i.e., the timing of the own vehicle and the other vehicle's respective arrival at the intersection point is approximately the same), the conventional device calculates the predicted time to collision (TTC), which is the time estimated until the own vehicle and the other vehicle collide (in other words, the time required until the own vehicle reaches the intersection point). If the TTC is below a predetermined TTC threshold, the conventional device determines that a collision is possible and executes collision avoidance control.

[0004] More specifically, collision avoidance control is executed in two stages. Specifically, conventional systems first execute warning control when the TTC falls below a predetermined first TTC threshold. Then, if the TTC continues to decrease and falls below a second TTC threshold (a value lower than the first TTC threshold) despite the execution of warning control, automatic braking control is executed. This configuration increases the likelihood that the driver will recognize the presence of another vehicle by executing warning control, allowing them to perform driving maneuvers to avoid a collision with the other vehicle, thereby reducing the frequency of automatic braking control.

[0005] Such collision avoidance control spanning two stages can be appropriately executed while the own vehicle is traveling straight, but is highly likely not to be appropriately executed when the own vehicle turns right.

[0006] That is, as described above, conventional devices determine the possibility of a collision based on the assumption that the predicted trajectories of the own vehicle and the other vehicle intersect. Therefore, when the predicted trajectories of the two vehicles do not intersect, no determination of the possibility of a collision is made. When the own vehicle turns right, the driver turns the steering wheel to the right to steer. However, in the brief period immediately following the start of the right turn (hereinafter referred to as the "first period"), the yaw rate is small, resulting in a large turning radius. As a result, the predicted trajectory during the first period becomes a sharp curve (a shape with a small curvature) compared to the actual trajectory during the right turn. Therefore, during the first period, the predicted trajectory of the own vehicle tends to extend toward the rear area of ​​the other vehicle (typically, the oncoming vehicle), making it difficult to intersect with the predicted trajectory of the other vehicle. Therefore, it is difficult to perform the process of determining the possibility of a collision during the first period. In addition, in the following description of right turns, "oncoming vehicle" is not referred to as "other vehicle" but as "oncoming vehicle."

[0007] Subsequently, as the yaw rate increases and the turning radius gradually decreases, the predicted trajectory of the own vehicle intersects with that of the oncoming vehicle, prompting a collision potential determination. However, at this point, the own vehicle has already made a certain turn, so even if an oncoming vehicle with collision potential is determined, the TTC is likely to have fallen below the first TTC threshold and be equal to or below the second TTC threshold. In other words, there is a high probability that warning control and automatic braking control will be executed simultaneously. Therefore, when the own vehicle turns right, there is a high probability that collision avoidance control will not be properly executed across both stages, resulting in the driver being unable to perform driving operations based on warning control to avoid a collision with the oncoming vehicle.

[0008] Therefore, research has been conducted on a technology for "control of notifying the driver of the presence of an oncoming vehicle (hereinafter referred to as "notification control")" that can be executed at a timing earlier than the automatic braking control even when turning right. For example, Patent Document 1 describes a technology related to a right-turn safety confirmation system for a vehicle that assists the driver in confirming safety when turning right. Specifically, the system includes an oncoming vehicle state detection unit and a collision possibility judgment unit. The oncoming vehicle state detection unit detects the state of an oncoming vehicle in an oncoming lane, and the collision possibility judgment unit judges the possibility of collision when turning right based on the state of the oncoming vehicle when the own vehicle stops and the right direction indicator is illuminated. Furthermore, the system is configured so that when the own vehicle stops with the right direction indicator illuminated (for example, when stopped at the right turn stop line at an intersection), the collision possibility judgment unit judges the possibility of collision when turning right based on the state of the oncoming vehicle, and issues a warning to the driver when it is judged that there is a possibility of collision.

[0009] Prior art literature

[0010] Patent Literature

[0011] Patent Document 1: Japanese Patent Application Laid-Open No. 2004-280453 Summary of the Invention

[0012] The system of Patent Document 1 is a technology specifically designed to issue a warning to the driver at a timing earlier than the automatic braking control when the own vehicle stops. However, since the notification control is executed at a timing earlier than the automatic braking control regardless of whether the own vehicle is in a stopped state, unnecessary work may occur. That is, since the determination of whether to execute the notification control is made at an early stage in the right turn process, it is difficult to accurately determine whether there is a possibility of collision, and unnecessary notification control may be executed even for an oncoming vehicle with an extremely low actual possibility of collision. In addition, an "oncoming vehicle with an extremely low actual possibility of collision" is, for example, an oncoming vehicle that is moving at a relatively far distance from the own vehicle, or an oncoming vehicle that passes near the own vehicle by slowing down or temporarily stopping in the future (without colliding with the own vehicle) while the own vehicle is turning right. Since the unnecessary work of the notification control can annoy the occupants of the own vehicle, it is desirable to develop a technology that can suppress such unnecessary work.

[0013] The above problem may occur in countries that regulate left-hand traffic (countries with a lane layout where the oncoming lane is located to the right of the driving lane). In countries that regulate right-hand traffic (countries with a lane layout where the oncoming lane is located to the left of the driving lane), the above description will be replaced with "left" to illustrate how the same problem may occur.

[0014] The present invention addresses the aforementioned issues. Specifically, one object of the present invention is to provide a vehicle notification control device capable of achieving both the desired performance of notification control at an earlier time than automatic braking control during a turn and the suppression of unnecessary operation of the notification control. Furthermore, "turning" means "turning right" in countries that regulate left-hand traffic, and "turning left" in countries that regulate right-hand traffic.

[0015] The vehicle notification control device of the present invention (hereinafter referred to as "the present device") comprises:

[0016] A surrounding information acquisition device (11) is capable of acquiring information about a solid object existing in front of a vehicle (V) and a lane dividing line extending in front of the vehicle as surrounding information;

[0017] A direction indicator switch (12) capable of detecting an operating state of an operator (WL) operated by a driver of the own vehicle in order to operate the direction indicator;

[0018] A vehicle speed detection device (13) capable of detecting the vehicle speed (v) of the own vehicle;

[0019] A driving operation state detection device includes at least one of a steering input value detection device (14) for detecting a steering input value (θs) based on a steering operation performed by the driver and a brake switch (114) for detecting whether or not a brake operation is performed by the driver;

[0020] Notification devices (21, 22) capable of performing notification actions; and

[0021] A control unit (10) capable of controlling the notification device,

[0022] The control unit is configured as follows:

[0023] When the direction of the opposite lane relative to the driving lane of the own vehicle is defined as a specific direction,

[0024] Based on the surrounding information, it is determined whether there is an oncoming vehicle (Vop) (step 610), the oncoming vehicle (Vop) being another vehicle moving in the oncoming lane in a direction approaching the own vehicle, and an imaginary extension line (Lo) extending from the other vehicle along the moving direction of the other vehicle passing the other vehicle in a specific direction relative to the current position of the own vehicle,

[0025] If the preconditions are satisfied that the oncoming vehicle is present (step 610: Yes) and the operator is in an operation state corresponding to the operation for activating the direction indicator on the specific direction side (step 620: Yes),

[0026] Based on vehicle information including at least one of a steering input value and the presence or absence of a brake operation and the vehicle speed, it is determined whether a crossing condition (condition 3, condition 5, condition 6) is satisfied (steps 630, 830, and 840), wherein the crossing condition is satisfied when there is a high probability that the own vehicle will complete crossing the oncoming lane or the intersection where the oncoming lane merges after a predetermined reference time (Tc, Ts).

[0027] When the direction opposite to the moving direction of the oncoming vehicle is defined as the longitudinal direction,

[0028] When an execution condition is satisfied, notification control is executed to notify the driver of the presence of the oncoming vehicle by causing the notification device to perform a notification action, the execution condition being satisfied when it is determined that the crossing condition is satisfied (step 630: yes, step 830: yes, step 840: yes) and it is determined that the hypothetical meeting time (Tx) is greater than a predetermined lower limit time (Tl) and less than a predetermined upper limit time (Tu) that is less than the reference time (step 640: yes, step 850: yes), the hypothetical meeting time (Tx) being the time required for the own vehicle and the oncoming vehicle to hypothetically meet in the longitudinal direction, assuming that the own vehicle moves in the longitudinal direction at a longitudinal speed (vy) that is the component of the vehicle speed in the longitudinal direction and the oncoming vehicle maintains its current moving state.

[0029] In the device of the present invention, when the prerequisite conditions are met, when the crossing condition is met and the hypothetical meeting time is greater than the lower limit time and less than the upper limit time (the time less than the reference time), the execution condition is set to be met, and the notification control is executed. According to this configuration, by setting the upper limit time to an appropriate value, "the crossing condition is met and the hypothetical meeting time is less than the upper limit time" means "assuming that the own vehicle moves while maintaining the current longitudinal speed and the oncoming vehicle moves while maintaining the current moving state, the own vehicle collides with the oncoming vehicle in the oncoming lane or at the intersection." In addition, by setting the lower limit time to an appropriate value, the notification control can be avoided when the oncoming vehicle is close enough for the driver to recognize the oncoming vehicle. Therefore, according to the device of the present invention, even without using a predicted trajectory, it is possible to appropriately determine the possibility of collision with the oncoming vehicle when turning. As a result, it is possible to take into account both the execution of the notification control at a timing earlier than the automatic braking control when turning and the suppression of unnecessary work of the notification control.

[0030] In one aspect of the present invention,

[0031] The driving operation state detection device is the steering input value detection device (14),

[0032] The vehicle information is first vehicle information including a steering angle (θs), a steering angular velocity (ωs), and the vehicle speed (v).

[0033] When a direction perpendicular to the longitudinal direction and oriented toward the specific direction is defined as a transverse direction,

[0034] The control unit (10) is configured as follows:

[0035] estimating a travel distance (d) assuming that the own vehicle (V) has moved for a first reference time (Tc) included in the reference time based on the first vehicle information,

[0036] Calculating the lateral movement distance (dy) as the component of the movement distance in the lateral direction,

[0037] When the lateral movement distance is equal to or greater than a predetermined distance threshold value (Dth), it is determined that the crossing condition (condition 3) is satisfied (step 630 : Yes).

[0038] According to this configuration, by setting the first reference time and distance thresholds to appropriate values, the accuracy of the execution conditions can be improved. In other words, unnecessary operations of the notification control can be suppressed.

[0039] In this case,

[0040] The distance threshold (Dth) is set to a value of an average lane width.

[0041] This configuration increases the likelihood that the first reference time will be sufficient to cross the oncoming lane or intersection within the first reference time period from the vehicle's current position when the crossing condition is met. This improves the accuracy of the execution conditions and reduces unnecessary notification control work.

[0042] In one aspect of the present invention,

[0043] The driving operation state detection device is the brake switch (114),

[0044] The vehicle information is second vehicle information including whether the braking operation is performed, the deceleration, and the vehicle speed (v).

[0045] The control unit (10) is configured as follows:

[0046] estimating a stopping time (T) required for the own vehicle (V) to stop based on the second vehicle information,

[0047] When the vehicle speed is above the predetermined vehicle speed threshold (vth) and the time required for stopping exceeds the second reference time (Ts) included in the reference time, it is determined that the crossing condition (condition 5, condition 6) is met (step 830: yes, step 840: yes).

[0048] According to this configuration, by setting the vehicle speed threshold and the second reference time to appropriate values, the accuracy of the execution condition can be improved. In other words, unnecessary operations of the notification control can be suppressed.

[0049] In the above description, to help understand the invention, the constituent elements of the invention corresponding to the embodiment are enclosed in parentheses with the reference numerals used in the embodiment, but the constituent elements of the invention are not limited to the embodiment specified by the reference numerals. BRIEF DESCRIPTION OF THE DRAWINGS

[0050] Figure 1 It is a schematic configuration diagram of a vehicle notification control device (first implementation device) according to a first embodiment of the present invention.

[0051] Figure 2A This is a diagram showing an example of a case where conditions 1-4 are met.

[0052] Figure 2B This is a diagram showing another example in which conditions 1 to 4 are met.

[0053] Figure 2C This is a diagram showing an example of a case where conditions 1-4 do not hold.

[0054] Figure 3 This is a diagram for explaining a method of setting an xy coordinate system.

[0055] Figure 4 This is a diagram for explaining the preconditions and the first execution condition of notification control.

[0056] Figure 5A This is a diagram for explaining unnecessary operations of notification control.

[0057] Figure 5B This is a diagram for explaining unnecessary operations of notification control.

[0058] Figure 6 This is a flowchart showing a routine executed by the CPU of the notification control ECU of the first embodiment.

[0059] Figure 7This is a schematic diagram showing the configuration of a vehicle notification control device (second embodiment) according to a second embodiment of the present invention.

[0060] Figure 8 This is a flowchart showing a routine executed by the CPU of the notification control ECU of the second embodiment.

[0061] Figure 9A This is a time chart showing a method of setting the upper limit time Tu when executing conventional notification control.

[0062] Figure 9B This is a time chart showing a method of setting the upper limit time Tu when the notification control according to the second embodiment is executed.

[0063] Description of Reference Numerals

[0064] 10: Notify control ECU;

[0065] 11: camera sensor;

[0066] 12: direction indicator switch;

[0067] 12R: right turn signal switch;

[0068] 12L: left turn indicator switch;

[0069] 13: Vehicle speed sensor;

[0070] 14: Steering angle sensor;

[0071] 21: Instrument panel;

[0072] 22: Speaker DETAILED DESCRIPTION

[0073] (First embodiment)

[0074] (constitute)

[0075] Hereinafter, a vehicle notification control device according to a first embodiment of the present invention (hereinafter also referred to as "first embodiment device") will be described with reference to the accompanying drawings. Figure 1As shown, the first implementation device includes a notification control ECU 10, and a camera sensor 11, a direction indicator switch 12, a vehicle speed sensor 13, a steering angle sensor 14, an instrument panel 21 and a speaker 22 connected to the notification control ECU 10. The notification control ECU 10 includes a microcomputer as a main part. ECU is the abbreviation of Electronic Control Unit. The microcomputer includes a CPU, ROM, RAM and an interface (I / F), etc. The CPU realizes various functions by executing instructions (programs, routines) stored in the ROM. Hereinafter, the vehicle equipped with the first implementation device will be referred to as the "own vehicle V" (this also applies to the vehicle equipped with the second implementation device in the second embodiment described later).

[0076] The notification control ECU 10 is configured to obtain information or signals output, detected, or generated by the sensors and switches 11 to 14 at predetermined intervals and control the elements (devices) 21 and 22 based on the obtained signals.

[0077] The camera sensor 11 (surrounding information acquisition device) is provided on the back of the interior mirror (internal mirror / rearview mirror) of the own vehicle V. The camera sensor 11 captures the scenery in front of the own vehicle, identifies (detects) the three-dimensional object in front of the own vehicle V based on the captured image data, and calculates the relative relationship between the own vehicle V and the three-dimensional object. Here, the "relative relationship between the own vehicle V and the three-dimensional object" includes the distance from the own vehicle V to the three-dimensional object, the orientation and relative speed of the three-dimensional object relative to the own vehicle V, etc. Three-dimensional objects include moving objects (for example, other vehicles and pedestrians), and stationary objects (for example, central median strips, guardrails, and roadside trees). In addition, a moving object refers to a three-dimensional object that can move, not just a moving three-dimensional object.

[0078] In addition, the camera sensor 11 identifies (detects) the dividing lines extending ahead of the vehicle V based on the image data described above, and calculates the shape of the lane (the area between two adjacent dividing lines) based on the identified dividing lines. In other words, the lane is defined by the dividing lines. The camera sensor 11 is capable of calculating the shapes of at least the driving lane (the lane in which the vehicle V is located), the primary adjacent lane adjacent to the driving lane, and the secondary adjacent lane adjacent to the primary adjacent lane (on the opposite side of the driving lane).

[0079] The camera sensor 11 outputs the information thus obtained to the ECU 10 as “surrounding information”.

[0080] The turn signal switch 12 (turn indicator switch) is turned on and off depending on the position of the turn signal lever (operator) WL. The turn signal lever WL is an operator operated by the driver to activate (flash) the turn signal (turn indicator) and is located on the steering column (not shown). The turn signal lever WL is configured to move about a support shaft to a right position (a position rotated to the right by a predetermined angle θ from the neutral position) and a left position (a position rotated to the left by an angle θ from the neutral position).

[0081] The turn signal switch 12 includes a right turn signal switch 12R and a left turn signal switch 12L. The right turn signal switch 12R is turned on (generates an on signal) when the turn signal lever WL is in the right position and is turned off (generates an off signal) otherwise. The left turn signal switch 12L is turned on (generates an on signal) when the turn signal lever WL is in the left position and is turned off (generates an off signal) otherwise. The ECU 10 obtains the signal generated by the turn signal switch 12 and detects the operating status of the turn signal lever WL based on the signal.

[0082] When the right or left winker switch 12R or 12L generates an on signal, the on signal is sent to an ECU (e.g., a meter ECU) that controls the operation of the winkers. The ECU activates (flashes) the corresponding right or left winker upon receiving the on signal.

[0083] The vehicle speed sensor 13 (vehicle speed detection device) detects a speed v of the own vehicle V (hereinafter referred to as “vehicle speed”) and outputs the detection signal to the ECU 10 .

[0084] The steering angle sensor 14 (steering input value detection device) detects the steering angle θs of the steering wheel and outputs the detection signal to the ECU 10. The steering angle θs is one type of input value based on the steering operation (steering wheel operation) performed by the driver. The steering angle sensor 14 is an example of a "driving operation state detection device."

[0085] The instrument panel 21 is located in front of the driver's seat of the vehicle V (where the driver can visually see the instrument panel). The speaker 22 is a component of a navigation system (not shown) and is located near a touch panel display (not shown). The instrument panel 21 and speaker 22 are examples of a "notification device."

[0086] (Details of the work)

[0087] Next, the details of the operation of the ECU 10 will be described. In a conventional configuration that determines whether to execute notification control based on the predicted trajectories of the vehicle V and the oncoming vehicle Vop, the shape of the predicted trajectories cannot be properly calculated during the first period (the brief period after the start of the right turn). As a result, notification control cannot be executed at a timing earlier than that of automatic braking control. On the other hand, executing notification control at a timing earlier than that of automatic braking control would easily result in unnecessary work. Therefore, in this embodiment, the ECU 10 is configured to determine the possibility of collision with the oncoming vehicle Vop without using the predicted trajectories.

[0088] Specifically, the ECU 10 first determines whether the precondition for notification control is met. This precondition is established when "the host vehicle V is likely to turn right when the oncoming vehicle Vop approaches." It is established when both conditions 1 and 2 below are met. In this specification, the direction of the oncoming lane relative to the driving lane is referred to as the "specific direction." In this embodiment (and the second embodiment described below), the specific direction is the right direction.

[0089] (Condition 1) An oncoming vehicle Vop is approaching.

[0090] (Condition 2) The right winker switch 12R is turned on.

[0091] First, Condition 1 will be described. Condition 1 is satisfied when the three-dimensional object included in the surrounding information satisfies all of the following four conditions.

[0092] (Condition 1-1) A three-dimensional object exists in the primary adjacent lane and / or the secondary adjacent lane.

[0093] (Condition 1-2) The type of the three-dimensional object is a vehicle.

[0094] (Condition 1-3) The speed of the three-dimensional object is greater than or equal to a predetermined speed threshold value voth.

[0095] (Condition 1-4) It is expected that a solid object will pass by the right side of the current position of the own vehicle V in the future.

[0096] The ECU 10 determines that condition 1-1 is satisfied if a solid object is present in the primary adjacent lane and / or the secondary adjacent lane as included in the surrounding information, and determines that condition 1-1 is not satisfied otherwise. Furthermore, if the intersection dividing line is cut off, the ECU 10 extends the dividing line in its extending direction to determine whether condition 1-1 is satisfied.

[0097] The ECU 10 is configured to identify the type of the three-dimensional object using a well-known pattern matching method. The ECU 10 determines that conditions 1-2 are met when the identified three-dimensional object is a vehicle, and determines that conditions 1-2 are not met otherwise.

[0098] The ECU 10 calculates the ground speed vo of the three-dimensional object based on the relative speed of the three-dimensional object included in the surrounding information. The ECU 10 determines that conditions 1-3 are met when the ground speed vo is greater than or equal to the speed threshold voth (|vo|≥voth), and otherwise determines that conditions 1-3 are not met.

[0099] Reference Figures 2A to 2C Conditions 1-4 are explained. Figures 2A to 2C The following are diagrams for explaining the method of determining whether the conditions 1-4 are satisfied. In the examples shown in these diagrams, it is assumed that the conditions 1-1 to 1-3 are satisfied. Figures 2A to 2C As shown, the ECU 10 calculates the direction of movement of the other vehicle Vo (see arrow) and sets a virtual extension line Lo extending along this direction. The direction of movement of the other vehicle Vo can be calculated based on the change in the position of the other vehicle Vo included in the surrounding information (i.e., the distance from the host vehicle V to the other vehicle Vo and the orientation of the other vehicle Vo relative to the host vehicle). Furthermore, the extension line Lo can be set, for example, as a ray originating from the center of the front end of the other vehicle Vo.

[0100] The ECU 10 determines that conditions 1-4 are met if the extension line Lo passes to the right (in a specific direction) of the current position of the own vehicle V; otherwise, it determines that conditions 1-4 are not met. The ECU 10 determines whether the extension line Lo passes to the right of the current position of the own vehicle V based on whether the extension line Lo intersects with an extension line L (described below). Specifically, the ECU 10 sets an imaginary line extending from the right front corner of the own vehicle V in the vehicle width direction (i.e., a direction perpendicular to the direction of movement of the own vehicle V (see arrow) and away from the own vehicle) as the extension line L. The ECU 10 then determines whether the extension line Lo intersects with the extension line L. If so, the ECU 10 determines that the extension line Lo passes to the right of the current position of the own vehicle V, i.e., it is expected that the other vehicle Vo will pass to the right of the current position of the own vehicle V in the future (conditions 1-4 are met). On the other hand, when there is no intersection, it is determined that the extension line Lo will not pass on the right side relative to the current position of the own vehicle V, that is, it is expected that other vehicles Vo will not pass on the right side of the current position of the own vehicle V in the future (conditions 1-4 do not hold).

[0101] exist Figure 2A and Figure 2BIn the example, the extended line Lo intersects the extended line L at points P1 and P2, respectively. Figure 2C In the example of , the extension line Lo does not intersect the extension line L. Therefore, the ECU 10 Figure 2A and Figure 2B In the example, it is determined that conditions 1-4 are met. In other words, condition 1 is met, and it is determined that the other vehicle Vo meets the "oncoming vehicle Vop that is approaching the own vehicle V". Figure 2C In the example, conditions 1-4 are determined to be false. In other words, condition 1 is false, and the other vehicle Vo is determined not to meet the criteria of "oncoming vehicle Vop approaching the host vehicle V." The order of determining conditions 1-1 through 1-4 is not restricted. Furthermore, condition 1-3 does not need to be included in the criteria for condition 1 to be met.

[0102] Next, condition 2 will be described. The ECU 10 determines that condition 2 is satisfied when the right winker switch 12R is on, and determines that condition 2 is not satisfied when the right winker switch 12R is off. "When the right winker switch 12R is on" may also mean that the winker stalk WL is in an operation state corresponding to an operation for activating the right winker. The order in which conditions 1 and 2 are determined is not limited.

[0103] When both conditions 1 and 2 are met, and thus the premise condition is met (i.e., the own vehicle V may turn right when the oncoming vehicle Vop is approaching), the ECU 10 determines whether the first execution condition of the notification control is met. The first execution condition is a condition that is met when "the own vehicle may collide with the oncoming vehicle Vop before completing the right turn", and is met when both conditions 3 and 4 below are met. In addition, "completing the right turn" means that when the own vehicle V turns right at the intersection, the rear end of the own vehicle V enters "an intersecting lane that intersects with the lane in which the own vehicle V was traveling before turning right at the intersection", which means that when the own vehicle V turns right in the opposite lane with the purpose of entering a parking lot of a facility along the opposite lane, the rear end of the own vehicle V enters the parking lot, etc.

[0104] (Condition 3) The lateral movement distance dy of the host vehicle V after the predetermined reference time Tc has elapsed is equal to or greater than a predetermined distance threshold value Dth.

[0105] (Condition 4) The time Tx required for the host vehicle V and the oncoming vehicle Vop to virtually meet in the longitudinal direction is equal to or greater than a predetermined lower limit time T1 and equal to or less than a predetermined upper limit time Tu (≤Tc).

[0106] First, condition 3 is explained. When the precondition is satisfied, the ECU 10 sets the xy coordinate system. Specifically, Figure 3 As shown, the ECU 10 sets the x-axis so that the positive x-axis is in the opposite direction of the movement of the oncoming vehicle Vop, with the front center of the own vehicle V as the origin. The y-axis is also set so that the positive y-axis is perpendicular to the x-axis and points in a specific direction (rightward in this embodiment). The origin is not limited to the front center of the own vehicle V. Hereinafter, the x-direction will be referred to as the "longitudinal direction," and the y-direction will be referred to as the "lateral direction."

[0107] Next, the ECU 10 decomposes the vehicle speed v obtained from the vehicle speed sensor 13 into a longitudinal component, namely a longitudinal velocity vx, and a lateral component, namely a lateral velocity vy. Based on the first vehicle information including the steering angle θs, the steering angular velocity ωs (the time-derivative value of the steering angle θs), and the lateral velocity vy obtained from the steering angle sensor 14, the ECU 10 uses a known method to estimate the travel distance d of the vehicle V assuming that the vehicle V has moved for a reference time Tc from the current time point. The lateral component of the travel distance d is then calculated as the "lateral travel distance dy." The estimation of the travel distance d is not limited to the current steering angle θs, the current steering angular velocity ωs, and the current lateral velocity vy. For example, the estimation may also be based on the rate of change of the steering angle θs, the rate of change of the steering angular velocity ωs, and the rate of change of the lateral velocity vy over a predetermined period up to the current time point. The first vehicle information may include a steering torque obtained from a steering torque sensor (not shown) instead of, or in addition to, the steering angle θs and the steering angular velocity ωs. The reference time Tc is an example of a "first reference time."

[0108] Next, the ECU 10 determines whether the lateral movement distance dy is greater than or equal to a predetermined distance threshold Dth. If dy ≥ Dth, Condition 3 is satisfied; if dy < Dth, Condition 3 is not satisfied. The reference time Tc is set to the average time required for the vehicle V to complete a lane crossing, for example, 4.0 seconds. Furthermore, the distance threshold Dth is set to the average lane width, for example, 3.5 meters.

[0109] That is, condition 3 is a condition that is met when there is a high possibility of completing the crossing of "an intersection (strictly speaking, an intersection merging with an opposite lane) or an opposite lane" when the own vehicle V moves the "average reference time Tc required to complete the lane crossing" from the current position. According to this structure, there is a high possibility that condition 3 will not be met when the own vehicle V changes lanes. Therefore, by introducing condition 3, it is possible to appropriately determine whether the reason for turning on the right direction indicator switch 12R of the own vehicle V is a right turn or a lane change. Condition 3 is equivalent to an example of a "crossing condition". In addition, hereinafter, "completing the crossing of an intersection or an opposite lane" is sometimes abbreviated as "completing the crossing of an intersection".

[0110] As can be seen from the above description, condition 3 is based on the premise that the lateral direction (y direction) is substantially parallel to the lane width direction (in other words, the moving direction (-x direction) of the oncoming vehicle Vop is substantially parallel to the extending direction of the oncoming lane)).

[0111] Next, condition 4 will be explained. The ECU 10 is configured to determine whether condition 4 is met when condition 3 is met. When condition 3 is met, the ECU 10 calculates the time Tx until the own vehicle V and the oncoming vehicle Vop hypothetically meet in the longitudinal direction, assuming that "the own vehicle V is moving in a straight line at a uniform speed vx and the oncoming vehicle Vop is moving while maintaining its current moving state." Here, "hypothetical meeting in the longitudinal direction" means that the own vehicle V and the oncoming vehicle Vop are close to each other in the longitudinal direction and their x-coordinates are temporarily consistent, and then the two separate in the longitudinal direction. In addition, the "time point of hypothetical meeting in the longitudinal direction" means the time point when the x-coordinate of the own vehicle V is consistent with the x-coordinate of the oncoming vehicle Vop. Since the own vehicle V and the oncoming vehicle Vop do not actually meet, the time Tx will also be referred to as the "hypothetical meeting time Tx" below. The virtual meeting time Tx can be calculated by dividing the longitudinal component of the distance from the own vehicle V to the oncoming vehicle Vop by the sum of the longitudinal velocity vx of the own vehicle V and the vehicle velocity vop of the oncoming vehicle Vop.

[0112] The ECU 10 determines whether the hypothetical meeting time Tx is greater than or equal to a predetermined lower limit time Tl and less than or equal to a predetermined upper limit time Tu. If Tl ≤ Tx ≤ Tu, condition 4 is satisfied. If Tx < Tl or Tu < Tx, condition 4 is not satisfied. Here, when the longitudinal position where the host vehicle V and the oncoming vehicle Vop hypothetically meet is defined as the "hypothetical meeting point Px," the hypothetical meeting point Px is offset in the +x direction by vx·Tx from the current position of the host vehicle V (in other words, the origin). The hypothetical meeting point Px is located farther away as the hypothetical meeting time Tx increases, and closer as the hypothetical meeting time Tx decreases. In other words, if the oncoming vehicle Vop is moving farther away and / or the vehicle speed vop is low (within a range above the speed threshold voth), the hypothetical meeting point Px is located farther away. Furthermore, when the oncoming vehicle Vop is moving nearby and / or the vehicle speed vop is relatively high, the virtual meeting point Px is located nearby.

[0113] For the upper limit time Tu, a predetermined value (e.g., 3.2 seconds) less than the reference time Tc is set. Since the time Tu satisfies Tu≤Tc, the virtual meeting point Px can be located within the intersection when condition 4 is met. Therefore, the upper limit time Tu can also be referred to as "the maximum value of the virtual meeting time Tx during which the virtual meeting point Px can remain within the intersection." Furthermore, when the distance between the own vehicle V and the oncoming vehicle Vop decreases to a certain extent during a right turn, the driver can recognize the oncoming vehicle Vop, so it is believed that the driver will spontaneously perform a driving operation (typically, a braking operation) to avoid a collision with the oncoming vehicle Vop (i.e., temporarily suspend the steering operation to turn right). Based on this understanding, for the lower limit time Tl, "the minimum value of the virtual meeting time Tx at which the driver is likely unable to recognize (visually confirm) the oncoming vehicle Vop and may therefore continue the steering operation to turn right" is set. The value of the lower limit time Tl is, for example, 1.0 second. Furthermore, the upper limit time Tu and the lower limit time Tl can also be configured to be changeable. That is, the time Tu and the time Tl may be set to different values ​​when the oncoming vehicle Vop is moving in the primary adjacent lane and when it is moving in the secondary adjacent lane. In this case, the reference time Tc and the distance threshold Dth may also be changed in accordance with the changes in the time Tu and the time Tl.

[0114] That is, condition 4 is a condition that is satisfied when there is a high possibility that the own vehicle V will collide with the oncoming vehicle Vop within the intersection (ie, before completing crossing the intersection) when turning right while maintaining the current longitudinal velocity vx.

[0115] When both conditions 3 and 4 are met, thus satisfying the first execution condition (i.e., there is a risk of collision between the host vehicle V and the oncoming vehicle Vop before the host vehicle V completes its right turn), the ECU 10 executes notification control (control that notifies the driver of the presence of the oncoming vehicle). Specifically, the ECU 10 executes the following processes 1 and 2 as notification control.

[0116] (Process 1) A predetermined mark (for example, a mark indicating that the oncoming vehicle Vop is approaching) is displayed on the instrument panel 21 .

[0117] (Process 2) A predetermined message (for example, a message “Be careful of approaching vehicles”) is output from the speaker 22.

[0118] Furthermore, the ECU 10 is configured to determine the need for notification control in parallel with the need for collision avoidance control. Automatic braking control, a type of collision avoidance control, is executed when the TTC for the oncoming vehicle Vop falls below a second TTC threshold. However, the lower limit time Tl is pre-set to a value such that the TTC does not fall below the second TTC threshold while Tl ≤ Tx holds. Therefore, automatic braking control does not occur while notification control is in effect.

[0119] Reference Figure 4 The preconditions and the first execution condition of the notification control will be described in more detail. Figure 4 The figure shows a portion of the process of the own vehicle V, which is moving in the +x direction on the driving lane 30, turning right at the intersection. In this example, the behavior of the own vehicle V and the other vehicle Vo is shown at times t=t1 and t=t2 (>t1). The driver of the own vehicle V does not perform any steering operation at t=t1, but performs steering operation to turn right at t=t2. The right turn signal switch 12R of the own vehicle V is turned on from a point in time slightly before time t reaches t1. In addition, the other vehicle Vo is moving at a speed that satisfies the speed threshold voth or above. In addition, the illustration of the xy coordinate system is omitted.

[0120] like Figure 4As shown, at t = t1 and t = t2, another vehicle Vo is located in the primary adjacent lane, is a vehicle, and is traveling at a speed greater than the speed threshold voth. Furthermore, the extension line Lo of the other vehicle Vo intersects the extension line L of the host vehicle V at points Pt1 (t = t1) and Pt2 (t = t2), respectively. Therefore, all conditions 1-1 through 1-4 are satisfied. Therefore, the ECU 10 determines that condition 1 is satisfied at t = t1 and t = t2 (i.e., the other vehicle Vo is an oncoming vehicle Vop moving in the oncoming lane 32 toward the host vehicle V). Hereinafter, the other vehicle Vo will be referred to as "oncoming vehicle Vop." Furthermore, at t = t1 and t = t2, the right indicator switch 12R of the host vehicle V is on, so the ECU 10 determines that condition 2 is satisfied. Consequently, the ECU 10 determines that the prerequisites for the notification control are satisfied.

[0121] Therefore, the ECU 10 determines whether condition 3 is satisfied, thereby determining whether the first execution condition for the notification control is satisfied. As described above, no steering operation is being performed at t = t1, so both the steering angle θs and the steering angular velocity ωs are approximately zero. Furthermore, since the vehicle V is moving in the +x direction, the vehicle speed v is equal to the longitudinal velocity vx, and the lateral velocity vy is zero (v = vx, vy = 0). Therefore, the lateral movement distance dy at t = t1 is zero, dy < Dth, and the ECU 10 determines that condition 3 is not satisfied at t = t1.

[0122] On the other hand, at t=t2, the steering operation is performed to turn right, resulting in the host vehicle V moving diagonally to the right and forward. If the lateral movement distance dy calculated based on the steering angle θs, the steering angular velocity ωs, and the lateral velocity vy at t=t2 satisfies dy ≥ D, the ECU 10 determines that condition 3 is satisfied at t=t2 (i.e., if the host vehicle V has moved for the reference time Tc from its current position, there is a high probability that the intersection (the intersection merging with the oncoming lane 32) has been crossed).

[0123] Next, ECU10 calculates the hypothetical meeting time Tx to determine whether condition 4 is met at t=t2. In this example, the own vehicle V and the oncoming vehicle Vop hypothetically meet in the longitudinal direction on a straight line Lp extending parallel to the y-axis. Therefore, the hypothetical meeting point Px is located at the intersection of the x-axis (refer to the dotted line) and the straight line Lp. When calculating the hypothetical meeting time Tx, ECU10 determines whether Tl≤Tx≤Tu is met. For example, if the hypothetical meeting time Tx at t=t2 is 2.0 seconds, Tl≤Tx≤Tu is met, so ECU10 determines that condition 4 is met at t=t2 (that is, when the own vehicle V maintains the current longitudinal speed vx and turns right, there is a high possibility of a collision with the oncoming vehicle Vop in the intersection). Based on the above, ECU10 determines that the first execution condition of the notification control is met at t=t2, and executes the notification control. In addition, Figure 4 The case where the vehicle V turns right at the intersection is described as an example. However, the ECU 10 also executes the same process when the vehicle V turns right into the opposite lane for the purpose of entering a parking lot or the like located along the opposite lane.

[0124] By executing notification control, the driver can recognize the presence of the oncoming vehicle Vop earlier than when automatic braking control is executed. This allows the driver to perform driving maneuvers to avoid collision with the oncoming vehicle Vop, reducing the frequency of automatic braking control execution. Furthermore, by setting the upper limit time Tu to a predetermined value less than the reference time Tc ("the maximum time Tx during which the virtual meeting point Px can remain within the intersection") and the lower limit time Tl to the "minimum time Tx during which the driver is likely unable to recognize the oncoming vehicle Vop and may continue steering to turn right," unnecessary notification control operations can be suppressed.

[0125] Reference Figure 5A and Figure 5B Explain unnecessary work for notification control. Figure 5A This is a diagram for explaining an example of unnecessary work when the upper limit time Tu is set to a value greater than the reference time Tc. In this example, conditions 1 to 3 are all met. Figure 5AAs shown, the oncoming vehicle Vop is moving farther away, so the virtual meeting time Tx is long. As a result, the virtual meeting point Px is located outside the intersection. This means that the virtual meeting time Tx is greater than the reference time Tc (Tx>Tc). Therefore, if the virtual meeting point Px is located outside the intersection, the host vehicle V will not collide with the oncoming vehicle Vop within the intersection. If the upper limit time Tu is greater than the reference time Tc, Tx≤Tu can also hold even in cases where the virtual meeting point Px is located outside the intersection. This can lead to the situation where notification control is executed for the oncoming vehicle Vop, which is actually unlikely to collide, resulting in unnecessary operation. To address this issue, in this embodiment, the upper limit time Tu is set to a predetermined value less than the reference time Tc ("the maximum time Tx that the virtual meeting point Px can remain within the intersection"). This prevents notification control from being executed when the virtual meeting point Px is located outside the intersection, thereby preventing unnecessary operation.

[0126] Figure 5B This is a diagram for explaining an example of unnecessary work when the lower limit time T1 is set to a value less than the "minimum value of the time Tx during which the driver is likely to continue the steering operation for turning right without being able to recognize that the oncoming vehicle Vop is highly likely". In this example, conditions 1 to 3 are all met. Figure 5B As shown, the oncoming vehicle Vop is moving relatively close, so the hypothetical meeting time Tx is short. As a result, the hypothetical meeting point Px is located near the own vehicle V. Since the driver can recognize the oncoming vehicle Vop at this point in time, there is a high probability that he or she will spontaneously perform a driving operation to avoid a collision. If the lower limit time Tl is set to the above-mentioned value, Tl ≤ Tx can also be established even in such a case where the driver spontaneously performs a collision avoidance operation. Therefore, a situation may arise where the notification control is performed for an oncoming vehicle Vop that the driver has already recognized, which becomes unnecessary work. To address this issue, in this embodiment, the lower limit time Tl is set to "the minimum value of the hypothetical meeting time Tx at which the driver is likely to be unable to recognize the oncoming vehicle Vop and may continue to perform the steering operation to turn right." As a result, the notification control is not performed when the oncoming vehicle Vop approaches to the extent that the driver can recognize the oncoming vehicle Vop, thereby suppressing unnecessary work.

[0127] Furthermore, if the driver does not spontaneously perform a collision avoidance maneuver even after time Tx falls below the lower limit time T1, the TTC for the oncoming vehicle Vop subsequently decreases and falls below the second TTC threshold, so automatic braking control is executed, thereby appropriately avoiding a collision with the oncoming vehicle Vop. Specifically, the purpose of the notification control is to notify the driver of the presence of the oncoming vehicle Vop when there is a high probability that the vehicle V will collide with the oncoming vehicle Vop before completing a right turn, but the driver cannot identify the oncoming vehicle Vop, rather than to notify the driver of the presence of the oncoming vehicle Vop even when the vehicle Vop is close enough for the driver to recognize the vehicle Vop.

[0128] (Specific work)

[0129] Next, the specific operation of the ECU 10 will be described. The CPU of the ECU 10 is configured to repeatedly execute the following operations every time a predetermined operation time elapses while the ignition switch is in the ON position. Figure 6 The routine is shown in the flowchart in .

[0130] When the predetermined timing comes, the CPU Figure 6 The process begins at step 600 and proceeds to step 610, where it determines whether an oncoming vehicle Vop is approaching based on surrounding information (condition 1). If there is no oncoming vehicle Vop, or if there is an oncoming vehicle Vop but it is not approaching (typically, it is turning), the CPU determines "no" in step 610 (i.e., condition 1 is not met (precondition not met)), proceeds to step 695, and temporarily ends this routine. On the other hand, if the oncoming vehicle Vop is approaching, the CPU determines "yes" in step 610 (i.e., condition 1 is met), and proceeds to step 620.

[0131] In step 620, the CPU determines whether the right blinker switch 12R is on (condition 2). If the right blinker switch 12R is off, the CPU determines "No" in step 620 (i.e., condition 2 is not met (precondition not met)), proceeds to step 695, and temporarily ends this routine. On the other hand, if the right blinker switch 12R is on, the CPU determines "Yes" in step 620 (i.e., condition 2 is met (precondition met)), and proceeds to step 630.

[0132] In step 630, the CPU determines whether the lateral movement distance dy of the host vehicle V after the reference time Tc has elapsed is greater than or equal to a distance threshold value Dth (Condition 3). If dy < Dth, the CPU determines "No" in step 630 (i.e., Condition 3 (the first execution condition) is not met), proceeds to step 695, and temporarily ends this routine. On the other hand, if dy ≥ Dth, the CPU determines "Yes" in step 630 (i.e., Condition 3 is met), and proceeds to step 640.

[0133] In step 640, the CPU determines whether the hypothetical meeting time Tx satisfies Tl ≤ Tx ≤ Tu (Tu ≤ Tc) (Condition 4). If Tx < Tl or Tu < Tx, the CPU determines "No" in step 640 (i.e., determines that Condition 4 does not hold (the first execution condition does not hold)), proceeds to step 695, and temporarily ends this routine. On the other hand, if Tl ≤ Tx ≤ Tu, the CPU determines "Yes" in step 640 (i.e., determines that Condition 4 holds (the first execution condition holds)), and proceeds to step 650.

[0134] In step 650, the CPU controls the instrument panel 21 to display a predetermined symbol and controls the speaker 22 to emit a predetermined message. Thus, the notification control is executed. Thereafter, the CPU proceeds to step 695 and temporarily ends this routine.

[0135] As described above, according to the first embodiment, it is possible to achieve both execution of the notification control at a timing earlier than the automatic braking control during a right turn and suppression of unnecessary operation of the notification control.

[0136] (Second embodiment)

[0137] Next, a vehicle notification control device according to a second embodiment of the present invention (hereinafter also referred to as the "second embodiment") will be described with reference to the accompanying drawings. Elements identical to those in the first embodiment are denoted by the same reference numerals. The second embodiment differs from the first embodiment in its method for determining whether the probability of the vehicle V completing the intersection crossing after a reference time has elapsed. The differences from the first embodiment will be described in detail below.

[0138] (constitute)

[0139] like Figure 7As shown, the second embodiment device includes a notification control ECU 110 (hereinafter also referred to as "ECU 110"). ECU 110 differs from ECU 10 in that it includes a brake switch 114 instead of the steering angle sensor 14. The brake switch 114 is turned on (generates an on signal) when the driver operates (steps on) a brake pedal (not shown), and is turned off (generates an off signal) when the brake pedal is not operated. ECU 110 obtains the signal generated by the brake switch 114 and detects whether the brake pedal is operated based on the signal. The brake switch is equivalent to an example of a "driving operation state detection device."

[0140] (Details of the work)

[0141] In this embodiment, the ECU 110 is also configured to determine the possibility of a collision with the oncoming vehicle Vop without using a predicted trajectory. Specifically, if both conditions 1 and 2 described in the first embodiment are met, and if these preconditions are met, the ECU 110 determines whether the second execution condition for the notification control has been met. The second execution condition is met when "there is a possibility of a collision with the oncoming vehicle Vop before the vehicle completes its right turn" and is met when all of the following conditions 5 through 7 are met.

[0142] (Condition 5) The vehicle speed v is equal to or greater than a predetermined vehicle speed threshold value vth.

[0143] (Condition 6) The time T required to stop the own vehicle V exceeds the reference time Ts.

[0144] (Condition 7) The hypothetical meeting time Tx is greater than or equal to the lower limit time T1 and less than or equal to the upper limit time Tu (≤Ts).

[0145] First, condition 5 is explained. When the prerequisite is met, ECU110 sets the xy coordinate system. Next, ECU110 determines whether the vehicle speed v is greater than the vehicle speed threshold vth. If v≥vth, it is determined that condition 5 is met, and if v<vth, it is determined that condition 5 is not met. For the vehicle speed threshold vth, "the minimum value of the vehicle speed v when the own vehicle V that has started the right turn completes the crossing without stopping in the intersection or the opposite lane" is set, and its value is, for example, 15 km per hour. That is, condition 5 is a condition that is met when the possibility of the own vehicle V stopping in the intersection or the opposite lane is low. Condition 5 is equivalent to an example of a "crossing condition".

[0146] Next, condition 6 will be described. The ECU 110 is configured to determine whether condition 6 is met when condition 5 is met. When condition 5 is met, the ECU 110 uses a well-known method to estimate the required stopping time T required for the own vehicle V to stop based on the second vehicle information including the presence or absence of brake pedal operation (presence or absence of brake operation) obtained from the brake switch 114, the deceleration (described later), and the vehicle speed v. Here, the deceleration is a negative acceleration and can be calculated based on the transition of the vehicle speed v. In addition, the second vehicle information may also include the presence or absence of brake operation obtained from other devices capable of detecting brake operations performed by the driver, instead of or in addition to the presence or absence of brake pedal operation.

[0147] ECU 110 determines whether the time required to stop, T, exceeds a reference time, Ts. If T > Ts, condition 6 is satisfied; if T ≤ Ts, condition 6 is not satisfied. Reference time Ts is set based on the typical time required for a driver to notice the presence of an oncoming vehicle Vop while turning right and attempt to stop their own vehicle V, and its value is, for example, 4.0 seconds. In other words, condition 6 is also satisfied when there is a high probability that the driver has not recognized the oncoming vehicle Vop. Furthermore, condition 6 is an example of a "crossing condition," and reference time Ts is an example of a "second reference time."

[0148] Next, condition 7 will be explained. The ECU 110 is configured to determine whether condition 7 is met when condition 6 is met. Condition 7 is the same as condition 4 in the first embodiment. Specifically, when condition 6 is met, the ECU 110 calculates the hypothetical meeting time Tx and determines whether time Tx is greater than the lower limit time Tl and less than the upper limit time Tu. The ECU 110 determines that condition 7 is met when Tl ≤ Tx ≤ Tu, and determines that condition 7 is not met when Tx < Tl or Tu < Tx. Furthermore, the values ​​for time Tu and time Tl are set for the same reasons as in the first embodiment, for example, Tu = 3.2 seconds and Tl = 1.0 seconds. In other words, condition 7 is met when there is a high probability of a collision with an oncoming vehicle Vop within the intersection (i.e., before completing the intersection crossing) while the host vehicle V maintains its current longitudinal velocity vx and makes a right turn. Furthermore, the reference time Ts is set to a value that satisfies Tu ≤ Ts.

[0149] When all conditions 5 to 7 are satisfied and thus the second execution condition is satisfied (ie, the host vehicle may collide with the oncoming vehicle Vop before completing the right turn), the ECU 110 executes notification control (process 1 and process 2).

[0150] According to this configuration, if condition 5 is not met, that is, if v < vth, the notification control is not executed. When v < vth and the precondition is met, there is a high probability that the driver will recognize the oncoming vehicle Vop and decelerate the vehicle V. Therefore, by not executing the notification control when the driver is likely to recognize the oncoming vehicle Vop, unnecessary work can be suppressed.

[0151] Furthermore, if condition 6 is not met, that is, if T ≤ Ts, the notification control is not executed. If the precondition v ≥ vth and T ≤ Ts is met, there is a high probability that the driver noticed the oncoming vehicle Vop while turning right and attempted to stop their own vehicle V. Therefore, by not executing the notification control when the driver is likely to recognize the oncoming vehicle Vop, unnecessary work can be suppressed.

[0152] (Specific work)

[0153] Next, the specific operation of ECU110 will be described. The CPU of ECU110 is configured to repeatedly execute the following operations every time a predetermined operation time elapses while the ignition switch is in the ON position. Figure 8 The routine shown in the flowchart in . This routine differs from the routine of the first embodiment in that the processing of steps 830 to 850 is performed instead of the processing of steps 630 and 640. Only the processing that is different from the first embodiment will be described below.

[0154] Step 830: The CPU determines whether the vehicle speed v is greater than or equal to the vehicle speed threshold vth (Condition 5). If v < vth, the CPU determines "No" in Step 830 (i.e., determines that Condition 5 does not hold (the second execution condition does not hold)), proceeds to Step 895, and temporarily ends this routine. On the other hand, if v ≥ vth, the CPU determines "Yes" in Step 830 (i.e., determines that Condition 5 holds), and proceeds to Step 840.

[0155] Step 840: The CPU determines whether the required stop time T exceeds the reference time Ts (Condition 6). If T ≤ Ts, the CPU determines "No" in step 840 (i.e., determines that Condition 6 does not hold (the second execution condition does not hold)), proceeds to step 895, and temporarily ends this routine. On the other hand, if T > Ts, the CPU determines "Yes" in step 840 (i.e., determines that Condition 6 holds), and proceeds to step 850.

[0156] Step 850: The CPU determines whether the hypothetical meeting time Tx satisfies Tl ≤ Tx ≤ Tu (Tu ≤ Ts) (Condition 7). If Tx < Tl or Tu < Tx, the CPU determines "No" in step 850 (i.e., determines that Condition 7 does not hold (the second execution condition does not hold)), proceeds to step 895, and temporarily ends this routine. On the other hand, if Tl ≤ Tx ≤ Tu, the CPU determines "Yes" in step 850 (i.e., determines that Condition 7 holds (the second execution condition holds)), and proceeds to step 650.

[0157] As described above, the second embodiment can also achieve the same effects as those of the first embodiment. Figure 9A and Figure 9B 2 is a diagram for explaining the effect of the second embodiment. Figure 9A : is a time chart showing a method of setting the upper limit time Tu when executing conventional notification control. Figure 9B This is a time chart illustrating how to set the upper limit time Tu when executing notification control in this embodiment. The horizontal axis of the time chart represents the elapsed time te from an arbitrary point in time immediately before the driver's brake operation, while the vertical axis represents the vehicle speed v and the hypothetical oncoming vehicle time Tx. In each time chart, notification control is executed when time Tx falls below the upper limit time Tu.

[0158] like Figure 9A and Figure 9B As shown, before the elapsed time te reaches time tb, the oncoming vehicle Vop approaches the own vehicle V such that vx + |vop| becomes a constant value. Therefore, during the period te < tb, the virtual meeting time Tx decreases linearly. While turning right, the driver notices the presence of the oncoming vehicle Vop and begins braking to stop the own vehicle V at time te = tb. Consequently, the vehicle speed v decreases at a constant deceleration. Furthermore, due to this decrease in longitudinal velocity vx, the virtual meeting time Tx increases at time te = tb, after which time Tx decreases nonlinearly (more specifically, it decreases in the form of an upwardly convex quadratic function).

[0159] In the past, Figure 9A As shown, the upper limit time Tu is configured to decrease gradually while the braking operation is continued. With this configuration, even if the upper limit time Tu is decreased, if the time point (te = tn) at which Tx ≤ Tu is reached falls before the time point (te = ts) at which the own vehicle V stops, even though the driver recognizes the oncoming vehicle Vop, the notification control will be executed at the time te = tn, resulting in unnecessary work.

[0160] In view of this, in this embodiment, if Figure 9BAs shown, the upper limit time Tu is reduced by a predetermined value at a time point after a time interval (time-lag) of Δt has passed since the start time point of the braking operation (te=tb). This is because, since the braking operation has been started, there is no need to consider the idling time. Thereafter, while the braking operation is continued, the upper limit time Tu slowly decreases, but when the vehicle speed v is less than the vehicle speed threshold vth at the time point te=tr, the upper limit time Tu is set to zero. This is because, as described above, when v<vth, there is a high possibility that the own vehicle V will stop in the intersection or in the opposite lane (that is, there is a high possibility that the driver will recognize the opposite vehicle Vop), and the necessity of executing the notification control is extremely low. In this way, according to the second implementation device, by appropriately changing the value of the upper limit time Tu, the possibility of executing the notification control even when there is a high possibility that the driver will recognize the opposite vehicle Vop can be greatly reduced, and unnecessary work of the control can be suppressed.

[0161] As mentioned above, the vehicle notification control device according to the present embodiment has been described. However, the present invention is not limited to the above-described embodiment, and various modifications can be made without departing from the purpose of the present invention.

[0162] For example, the above embodiment describes a case where the specific direction is right, but the present invention is not limited to this. The present invention can also be applied to a case where the specific direction is left. In this case, the configuration can be described by replacing "right" with "left" and "left" with "right" in the above embodiment. Furthermore, the present invention can also be applied to vehicles that travel using automated driving (automatic driving control) (so-called automated driving vehicles).

Claims

1. A vehicle notification control device comprising: a surrounding information acquisition device capable of acquiring, as surrounding information, information on a solid object existing in front of the own vehicle and a lane dividing line extending in front of the own vehicle; a direction indicator switch capable of detecting an operating state of an operator operated by the driver of the own vehicle to activate the direction indicator; A vehicle speed detection device capable of detecting the speed of the own vehicle; a driving operation state detection device comprising at least one of a steering input value detection device for detecting a steering input value based on a steering operation performed by the driver, and a brake switch for detecting the presence or absence of a brake operation performed by the driver; a notification device capable of performing a notification action; as well as A control unit capable of controlling the notification device, The control unit is configured as follows: When the direction of the opposite lane relative to the driving lane of the own vehicle is defined as a specific direction, Based on the surrounding information, it is determined whether there is an oncoming vehicle, which is another vehicle moving in the oncoming lane in a direction approaching the own vehicle and is another vehicle whose imaginary extension line extending from the other vehicle in the moving direction passes by a specific direction side relative to the current position of the own vehicle; If the preconditions are satisfied, which are satisfied when it is determined that the oncoming vehicle is present and the operator is in an operation state corresponding to an operation for operating the direction indicator on the specific direction side, determining whether a crossing condition is satisfied based on vehicle information including at least one of a steering input value and the presence or absence of a brake operation, and a vehicle speed, the crossing condition being satisfied when there is a high probability that the own vehicle will complete crossing the oncoming lane or the intersection where the oncoming lane merges after a predetermined reference time has passed; When the direction opposite to the moving direction of the oncoming vehicle is defined as the longitudinal direction, When the execution conditions are met, executing notification control for notifying the driver of the presence of the oncoming vehicle by causing the notification device to perform a notification operation, The execution condition is satisfied when it is determined that the crossing condition is satisfied and when it is determined that the hypothetical passing time is greater than or equal to a predetermined lower limit time and less than or equal to a predetermined upper limit time, the predetermined upper limit time being less than or equal to the reference time, the hypothetical passing time being a time required for the self-vehicle and the oncoming vehicle to hypothetically pass each other in the longitudinal direction, assuming that the self-vehicle moves in the longitudinal direction at a longitudinal velocity that is the longitudinal component of the vehicle speed and that the oncoming vehicle maintains its current moving state. The driving operation state detection device is the brake switch, The vehicle information is second vehicle information including whether the braking operation is performed, the deceleration, and the vehicle speed. The control unit is configured as follows: estimating a stopping time required for the own vehicle to stop based on the second vehicle information, When the vehicle speed is equal to or higher than a predetermined vehicle speed threshold and the required stopping time exceeds a second reference time included in the reference time, it is determined that the crossing condition is satisfied. The control unit is configured to determine whether the notification control needs to be executed without using the predicted trajectories of the own vehicle and the oncoming vehicle.

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