JP5407410B2 - Driving support device and driving support method - Google Patents

Description

  The present invention relates to a driving support device and a driving support method that support a driving operation when deceleration of a vehicle is required.

  Based on information from the navigation device and infrastructure, the road shape ahead of the course is acquired, and before entering the curve, automatic deceleration is performed so that the entry speed is suitable for the curve, and a voice or There was what notified a driver by display (refer to patent documents 1).

JP-A-4-236699

However, even if the automatic deceleration is notified by voice or display, there is a possibility that it cannot be effectively notified depending on the driver's line-of-sight direction and surrounding noise.
The subject of this invention is notifying a driver | operator effectively that deceleration of a vehicle is needed.

In order to solve the above problem, the driving support device according to the present invention determines a deceleration timing that is a timing at which the host vehicle should start deceleration according to a road shape ahead of the host vehicle path, and from the determined deceleration timing. in even a previous point in time, the operation reaction force with respect to acceleration or deceleration operation by the driver, to correct the deceleration promotion direction, Ru is decelerating the vehicle deceleration timing. In addition, when determining the deceleration timing, a point where the radius of curvature is closest to the host vehicle and closest to the host vehicle is calculated as a control target point according to the road shape, and the calculated radius of curvature at the control target point is calculated. Based on this, the target vehicle speed when passing through the control target point is calculated. Then, the target deceleration of the host vehicle is calculated based on the target vehicle speed, the distance to the control target point, and the current vehicle speed, and when the target deceleration is larger than a predetermined deceleration start threshold, the host vehicle decelerates. Is determined to be the deceleration timing at which to start. Also, a correction start threshold value smaller than the deceleration start threshold value is set, and correction is started when the target deceleration becomes larger than the correction start threshold value. When making a correction, the greater the difference between the target deceleration and the correction start threshold, the greater the amount of correction in the deceleration acceleration direction for the operation reaction force, and the higher the host vehicle speed, the more the correction starts for the deceleration timing. Increase the timing difference.

  According to the driving support apparatus of the present invention, the deceleration timing at which the host vehicle should start deceleration is determined, and the operation reaction force with respect to the acceleration / deceleration operation of the driving is determined at the time before the determined deceleration timing. Thus, it is possible to effectively notify the driver that the vehicle needs to be decelerated.

1 is a schematic configuration of a vehicle. It is a flowchart which shows a driving assistance process. It is an example of selection of a target node point. It is a map used for calculation of coefficient Ks. It is a map used for calculating the early Factor X _A (vehicle speed). It is a map used for calculating the early Factor X _A (for road gradient).

Hereinafter, embodiments of the present invention will be described with reference to the drawings.
"Constitution"
FIG. 1 is a schematic configuration of a vehicle.
The brake pedal 1 is connected to the master cylinder 3 via a brake booster 2. The brake booster 2 is a control-type booster that can adjust the boost ratio by changing the supply amount of negative pressure, for example, and is driven and controlled by the controller 10. By adjusting the boost ratio, the reaction force against the driver's pedal operation is controlled.

  A brake actuator 5 used for stability control (VDC: Vehicle Dynamics Control) or the like is interposed between the master cylinder 3 and each wheel cylinder 4i (i = FL, FR, RL, RR). The brake actuator 5 includes hydraulic devices such as solenoid valves and pumps, and these are driven and controlled by the controller 10 to individually control the hydraulic pressure of each wheel cylinder 4i regardless of the driver's brake operation. Can do.

The driving force control device 20 controls the driving force of the vehicle by controlling the fuel injection amount and ignition timing of the engine 21, the gear ratio of the automatic transmission 22, and the opening degree of the electronic control throttle valve 23. Further, when the driving force control device 20 receives the driving force command from the controller 10, the driving force control device 20 controls the driving force of the vehicle in accordance with the driving force command.
The radar device 31 detects an inter-vehicle distance D to an object ahead of the vehicle and inputs it to the controller 10.

The navigation device 32 detects the road shape ahead of the host vehicle based on the current position (X ₀ , Y ₀ ) of the host vehicle measured by GPS and the road map information. Here, the road shape is node point information, and consists of X _j , Y _j , L _j (j = 1 to n, n is an integer). X _j and Y _j are node point position information, and L _j is a distance from the current position (X ₀ , Y ₀ ) to the node point (X _j , Y _j ). The node points farther from the current position are arranged so that the value of j becomes larger. The current position (X ₀ , Y ₀ ) may be corrected based on the vehicle speed and the yaw rate. If the road shape is available from the infrastructure, use it. Further, the acquired road map information and the current position of the host vehicle are displayed on a display or the like.

The monitor 33 displays information to be notified to the driver in response to a command from the controller 10, and notifies the driver 33 by voice or a buzzer via a built-in speaker.
The acceleration sensor 11 detects the longitudinal acceleration Xg and the lateral acceleration Yg of the vehicle, the yaw rate sensor 12 detects the yaw rate γ of the vehicle, and the steering angle sensor 13 detects the rotation angle of the steering wheel 6, that is, the driver's steering operation. Detect the amount. The pressure sensor 14 detects the pressure of the master cylinder 3, and the wheel speed sensor 15i detects the rotational speed of the wheel 7i. Each detection signal is input to the controller 10.

A reaction force motor 35 is connected to the accelerator pedal 34, and the accelerator sensor 16 detects the accelerator operation amount (accelerator opening) of the driver according to the rotation angle of the reaction force motor 35 and inputs it to the controller 10. The reaction force motor 35 is driven and controlled by the controller 10, and the reaction force motor 35 controls the operation reaction force against the driver's pedal operation.
When the above-mentioned various data have left and right directions, the left direction is a negative value and the right direction is a positive value. That is, the yaw angle φ and the steering angle δ are negative values when turning left and positive values when turning right.
The controller 10 executes the deceleration control process with a timer interrupt every predetermined time.

FIG. 2 is a flowchart showing the deceleration control process.
First, in step S1, various data are read.
In the subsequent step S2, the average wheel speed is calculated as the vehicle speed V using the wheel speeds Vw1 and Vw2 of the non-driven driven wheels as shown in the following equation (1).
V = (Vw1 + Vw2) / 2 (1)

In the subsequent step S3, the curvature radius Rn of each node point is calculated based on the coordinates of each node point. Several methods can be considered for calculating the curvature radius Rn itself. For example, as shown in the following equation (2), the curvature radius Rn is calculated from the coordinates of three consecutive node points. f is a function for calculating the radius of curvature Rn from the coordinates of the three node points.
Rn = f (X _(j-1) , Y _(j-1) , X _(j) , Y _(j) , X _{(j + 1)} , Y _{(j + 1)} )
………… (2)

  Here, the radius of curvature Rn is calculated from the coordinates of three consecutive node points. However, the radius of curvature Rn may be calculated based on the angle of a straight line connecting the preceding and following node points. In addition, instead of calculating the curvature radius Rn each time, the curvature radius Rn of each node point may be stored in advance as node information in the map data, and the value may be read. Further, it is also possible to create complementary points that divide each node point at equal intervals so as to pass through each node point, and calculate the curvature radius Rn for each of the created complementary points.

  In subsequent step S4, a target node point to be controlled is calculated. In the present embodiment, the target node point to be controlled is calculated from the node points ahead of the host vehicle according to the radius of curvature. The present invention is set based on the curvature radius of an actual curve due to a driver's eye mismeasurement, etc., and tries to drive a corner at a vehicle speed higher than the vehicle speed (passable speed) that allows the driver to pass the curve without feeling uncomfortable. Therefore, control is performed on the position closest to the host vehicle and having the smallest curvature radius Rn. Therefore, as shown in FIG. 3, the target node point is the first minimum value of the radius of curvature Rn ahead of the host vehicle, that is, the point where the radius of curvature is the closest to the host vehicle and becomes the smallest.

In the subsequent step S5, the friction coefficient μ of the road surface is estimated as shown in (3) below in accordance with the relationship between the braking / driving force of each wheel and the slip ratio.
μ = g (braking / driving force of each wheel, slip ratio of each wheel) (3)
If the friction coefficient μ of the road surface is available from the infrastructure, it may be used. In addition, the friction coefficient μ may be estimated at the driver's discretion. For example, a switch that can be switched to a rough stage such as high, medium, and low is provided, and this can be selected and operated at the discretion of the driver. Good.

In subsequent step S6, as shown in the following equation (4), the allowable lateral acceleration Yg _LIM is calculated according to the friction coefficient μ of the road surface. Ks is a coefficient, for example, a value of about 0.8.
Yg _LIM = Ks × μ (4)
Instead of calculating the coefficient Ks, the coefficient Ks may be calculated according to the vehicle speed with reference to the map of FIG. This map is set so that the coefficient Ks decreases as the vehicle speed increases. Therefore, the allowable lateral acceleration Yg _LIM decreases as the vehicle speed increases.
In the following step S7, as shown in the following equation (5), the target vehicle speed Vr when passing through the target node point is calculated according to the curvature radius Rn of the target node point and the allowable lateral acceleration Yg _LIM .
Vr = √ (Yg _LIM × | Rn |) (5)

In the subsequent step S8, as shown in the following equation (6), the target deceleration Xg is calculated according to the vehicle speed V, the target vehicle speed Vr, and the distance L to the target node point. The target deceleration Xg indicates deceleration when the value is positive, and indicates acceleration when the value is negative.
^{Xg = (V 2 -Vr 2)} / 2L
= (V ² -Yg _LIM × | Rn |) / 2L (6)
According to the above equation (6), when V> Vr, the target deceleration Xg increases as the vehicle speed V increases and the target vehicle speed Vr decreases. Further, the target deceleration Xg increases as the allowable lateral acceleration Yg decreases and the curvature radius Rn decreases. Moreover, the target deceleration Xg increases as the distance L to the target node point is shorter.

In a succeeding step S9, it is determined whether or not an alarm flag indicating an alarm operating state has been reset to F _W = 0. If the determination result is F _W = 0, it is determined that the alarm is inactive, and the process proceeds to step S10. On the other hand, if the determination result is F _W = 1, it is determined that the alarm has already been activated, and the process proceeds to step S13.
In step S10, it is determined whether or not the target deceleration Xg is greater than or equal to the alarm start threshold th _W. If the determination result is Xg ≧ th _W , it is determined that an alarm for prompting deceleration is necessary, and the process proceeds to step S11. On the other hand, if the determination result is Xg <th _W , it is determined that an alarm for prompting deceleration is unnecessary, and the process proceeds to step S14.

In step S11, the monitor 33 is driven, and an alarm for prompting deceleration is issued by display or sound.
In the subsequent step S12, the warning flag is set to F _W = 1, and then the process proceeds to step S16.
In step S13, it is determined whether or not the target deceleration Xg is greater than or equal to the alarm cancellation threshold (th _W −K _W ). K _W is a hysteresis for preventing alarm ON / OFF hunting, and is set to a value of about 0.03 G, for example. If the determination result is Xg ≧ (th _W −K _W ), it is determined that an alarm for prompting deceleration is still necessary, and the process proceeds to step S11. On the other hand, if the determination result is Xg <(th _W −K _W ), it is determined that the alarm for prompting deceleration is no longer necessary, and the process proceeds to step S14.

In step S14, the alarm is terminated.
In the subsequent step S15, the alarm flag is reset to F _W = 0, and then the process proceeds to step S16.
In step S16, it is determined whether or not the deceleration flag indicating the operating state of the deceleration control has been reset to F _R = 0. If the determination result is F _R = 0, it is determined that the deceleration control is in an inoperative state, and the process proceeds to step S17. On the other hand, if the determination result is F _R = 1, it is determined that the deceleration control is already in operation, and the process proceeds to step S20.

In step S17, it determines whether the target deceleration Xg is deceleration start threshold th _R or more. th _R is a value slightly larger than th _W. If the determination result is Xg ≧ th _R, it is determined that deceleration control is necessary, and the process proceeds to step S18. On the other hand, if the determination result is Xg <th _R , it is determined that the deceleration control is unnecessary, and the process proceeds to step S21.
In step S18, deceleration control is executed by braking force control and driving force suppression.

[Brake force control]
First, as shown in the following equation (7), the target braking hydraulic pressure Pc is calculated according to the target deceleration Xg. Kb is a constant according to the brake specifications.
Pc = Kb × Xg (7)
Then, as shown in the following equation (8), the target braking hydraulic pressure Pc and the master cylinder pressure Pm are compared, and the selected high is set as a new target braking hydraulic pressure Pc.
Pc ← max [Pc, Pm] (8)
Then, the optimal front / rear wheel braking force distribution is determined, the target brake fluid pressure Pi of each wheel is calculated according to the target brake fluid pressure Pc, and the brake actuator 5 is driven and controlled to realize the target brake fluid pressure Pi. To do.

[Driving force control]
Here, as shown in the following equation (9), a target driving torque T is calculated, and a driving force command corresponding to the target driving torque T is output to the driving force control device 20. Fa is a normal driving torque according to the driver's accelerator operation, and G is a braking torque expected to be generated according to the target braking fluid pressure Pc.
T = Fa-G (9)
Thus, the vehicle is effectively decelerated by increasing the braking force and suppressing the engine output.
In the subsequent step S19, the deceleration flag is set to F _R = 1, and then the process proceeds to step S23.

In step S20, it is determined whether or not the target deceleration Xg is equal to or greater than the deceleration cancellation threshold (th _R −K _R ). K _R is hysteresis for preventing hunting of ON / OFF of deceleration control, and is set to a value of about 0.05 G, for example. If the determination result is Xg ≧ (th _R −K _R ), it is determined that deceleration control is still necessary, and the process proceeds to step S18. On the other hand, if the determination result is Xg <(th _R −K _R ), it is determined that the deceleration control is no longer necessary, and the process proceeds to step S21.

In step S21, the deceleration control is terminated.
In the subsequent step S22, the deceleration flag is reset to F _R = 0, and then the process proceeds to step S23.
In step S23, the timing for starting the AF increase correction to the accelerator operation, an early factor X _A for advancing the timing at which to start the deceleration control is calculated in accordance with at least one of the vehicle speed and the road gradient.

First, the early coefficient X _A is calculated according to the vehicle speed with reference to the map of FIG. This map is set such that the higher the vehicle speed, the smaller the early coefficient X _{A in} the range from the maximum value X _MAX to the minimum value X _MIN .
Further, the early coefficient X _A is calculated according to the road surface gradient with reference to the map of FIG. In this map, when the road surface gradient is 0, the early coefficient X _A becomes the intermediate value X _MID , and as the downward gradient increases, the early coefficient X _A increases in the range from the intermediate value X _MID to the maximum value X _MAX. The early coefficient X _A is set to be smaller in the range from the intermediate value X _MID to the minimum value X _{MIN as} the gradient increases.

In addition, when calculating the early coefficient X _A according to both the vehicle speed and the road surface gradient, the average value of the early coefficient X _A calculated individually may be used or added after weighting.
In a succeeding step S24, it is determined whether or not the correction flag indicating the execution state of the reaction force correction is reset to F _A = 0. If the determination result is F _A = 0, it is determined that the reaction force correction is not performed, and the process proceeds to step S25. On the other hand, if the determination result is F _A = 1, it is determined that the reaction force correction has already been performed, and the process proceeds to step S28.

In step S25, it is determined whether or not the target deceleration Xg is equal to or greater than the correction start threshold (th _R −X _A ). If the determination result is Xg ≧ (th _R −X _A ), it is determined that deceleration needs to be promoted, and the process proceeds to step S26. On the other hand, if the determination result is Xg <(th _R −X _A ), it is determined that it is not necessary to promote deceleration, and the process proceeds to step S28.
In step S26, the reaction force motor 35 is driven, and the normal reaction force corresponding to the accelerator operation is increased and corrected. Here, the increase correction amount is increased as the difference between the target deceleration Xg and the predetermined value (th _R −X _A ) is larger.

In the subsequent step S27, the correction flag is set to F _A = 1, and then the process returns to a predetermined main program.
In step S28, it is determined whether or not the target deceleration Xg is equal to or greater than a correction cancellation threshold (th _R −X _A −K _R ). If the determination result is Xg ≧ (th _R −X _A −K _R ), it is determined that it is still necessary to promote deceleration, and the process proceeds to step S26. On the other hand, if the determination result is Xg <(th _R −X _A −K _R ), it is determined that it is no longer necessary to promote deceleration, and the process proceeds to step S29.
In step S29, the reaction force correction ends.
In subsequent step S30, the correction flag is reset to F _A = 0, and then the process returns to a predetermined main program.

<Action>
First, the target deceleration Xg of the vehicle is calculated based on the road shape acquired from the navigation device 32 (steps S3 to S8). At this time, when the vehicle approaches a curve, the target deceleration Xg calculated based on the road shape gradually increases.
When the target deceleration Xg is equal to or greater than the alarm start threshold th _W (determination in step S10 is “Yes”), the monitor 33 is driven to issue an alarm for prompting deceleration by display or sound (step S11). If the target deceleration Xg becomes less than the alarm start threshold (th _W −K _W ) by executing a deceleration operation such as the driver quickly decelerating the accelerator operation or shifting to a braking operation by this alarm ( When the determination in step S13 is “No”), the alarm is terminated (step S14). Since the deceleration start threshold th _R is larger than the alarm start threshold th _W , the deceleration control is not started at this time.

On the other hand, even if the alarm is started, when the driver does not immediately execute the deceleration operation and the target deceleration Xg becomes equal to or greater than the deceleration start threshold th _R (determination in Step S17 is “Yes”), the brake actuator 5 Then, the driving force control device 20 is driven, and deceleration control is performed by increasing the braking force and suppressing the driving force (step S18). If the target deceleration Xg becomes less than the deceleration release threshold (th _R −K _R ) by this deceleration control (determination in Step S20 is “No”), the deceleration control is terminated (Step S21).

In this way, the road shape ahead of the vehicle's path is acquired, and before entering the curve, automatic deceleration is performed so that the entry speed is suitable for the curve, and this is notified to the driver by voice or display. By doing so, driving assistance can be performed.
By the way, even if it is notified by voice or display that automatic deceleration is performed, there is a possibility that it cannot be effectively notified depending on the driver's line-of-sight direction and surrounding noise.
Thus, in the present embodiment, the deceleration timing at which the host vehicle should start deceleration is determined according to the road shape ahead of the host vehicle track, and the reaction force against the accelerator operation during driving is determined at a time before the determined deceleration timing. Increase the correction.

Specifically, first, a correction start threshold (th _R −X _A ) obtained by subtracting the early coefficient X _A from the deceleration start threshold th _R is set, and the target deceleration Xg is equal to or greater than the correction start threshold (th _R −X _A ). If this is the case (determination in step S25 is "Yes"), the operation reaction force is increased and corrected (step S26). That is, since the correction start threshold value (th _R −X _A ) is smaller than the deceleration start threshold value th _R , the operation reaction force of the accelerator pedal 34 is always stronger than when the deceleration control is started. Accordingly, it is possible to effectively notify the driver that the vehicle needs to be decelerated and to prompt the driver to perform a decelerating operation.

At this time, the higher the vehicle speed, the smaller the correction start threshold (th _R −X _A ) by increasing the early coefficient X _A (step S23, FIG. 5). As a result, the target deceleration Xg is likely to exceed the correction start threshold (th _R −X _A ), so the timing difference for starting the reaction force correction with respect to the deceleration timing becomes large, and the reaction force correction is started earlier. . Therefore, when the vehicle is traveling at a high speed, it is possible to prompt the driver to perform a deceleration operation with a sufficient margin before entering the curve, thereby giving the driver a sense of security.

Further, the early coefficient X _A is also changed according to the road surface gradient (step S23, FIG. 6), and the correction start threshold value (th _R −X _A ) is adjusted.
First, the greater the downward gradient, the smaller the correction start threshold (th _R −X _A ) by increasing the early coefficient X _A. As a result, the target deceleration Xg is likely to exceed the correction start threshold (th _R −X _A ), so the timing difference for starting the reaction force correction with respect to the deceleration timing becomes large, and the reaction force correction is started earlier. . Therefore, in situations where the vehicle speed is likely to increase, such as downhill roads, the driver can be urged to decelerate with a sufficient margin before entering the curve, giving the driver a sense of security. .

On the other hand, the correction start threshold (th _R −X _A ) is increased by decreasing the early coefficient X _A as the ascending gradient increases. As a result, the target deceleration Xg is unlikely to exceed the correction start threshold (th _R −X _A ), so although it is faster than the deceleration control is started, the timing difference for starting the reaction force correction with respect to this deceleration timing. Becomes smaller. Therefore, in a situation where the vehicle speed is likely to decelerate, such as downhill roads, the driver is prevented from unnecessarily urging the decelerating operation, and the driver does not feel uncomfortable.

Further, the early coefficient X _A is limited to a range from the maximum value _MAX to the minimum value X _MIN . As a result, it is possible to prevent the reaction force correction from being unnecessarily accelerated when the vehicle speed is too high or the descending slope is too large. On the other hand, although the vehicle speed is low or the ascending slope is large and the vehicle is in a situation where it is easy to decelerate, the timing difference for starting the reaction force correction with respect to the deceleration timing becomes too small, and the difference is The situation that it cannot recognize can be prevented.

Further, as the difference between the target deceleration Xg and the correction start threshold (th _R −X _A ) is larger, the increase correction amount of the pedal reaction force with respect to the accelerator operation is increased. Accordingly, the driver can grasp how much the vehicle should decelerate now from the magnitude of the pedal reaction force.
Thus, when the target deceleration Xg becomes less than the correction cancellation threshold (th _R −X _A −K _R ) due to the increase in the reaction force of the accelerator pedal 34 (the determination in step S28 is “No”), the reaction force correction is terminated. (Step S29).

《Application example》
In the present embodiment, the deceleration force is increased by increasing the reaction force of the accelerator pedal 34 before the deceleration control is performed, but the present invention is not limited to this. That is, the driver is not necessarily performing the accelerator operation, and may be performing the brake operation. Therefore, before performing the deceleration control, it is determined whether the driver is operating the accelerator or the brake, and when the brake is operated, the reaction force of the brake pedal 1 is reduced to reduce the brake. Further depression of the pedal 1 may be prompted.
In the present embodiment, the case where deceleration control is performed has been described. However, the present invention is not limited to this, and the configuration is such that an alarm is issued and reaction force correction is performed before entering a curve. May be.

"effect"
From the above, the accelerator pedal 34 and the brake pedal 1 correspond to the “driving operator”, the reaction force motor 33 and the brake booster 2 correspond to the “reaction force control means”, and the processing of the navigation device 32, steps S3 and S4 is performed. Corresponds to “detection means”. Further, the processes of steps S16, S17, and S20 correspond to “determination means”, the brake actuator 5, the driving force control device 20, and the processes of step S18 correspond to “deceleration control means”, and the processes of steps S23 to S30. Corresponds to “correction means”.

(1) A driving operator that is accelerated / decelerated by the driver, a reaction force control means that applies an operating reaction force to the driving operator according to the acceleration / deceleration operation of the driver, and a road shape in front of the host vehicle path Detecting means for detecting, determining means for determining a deceleration timing that is a timing at which the host vehicle should start deceleration according to the road shape detected by the detecting means, and a time point before the deceleration timing determined by the determining means And correction means for starting correction in the deceleration acceleration direction with respect to the operation reaction force.
As described above, by controlling the reaction force to the acceleration / deceleration operation of the driving in the deceleration acceleration direction at a time before the deceleration timing, the driver is effectively notified that the vehicle needs to be decelerated. be able to.

(2) The determination means calculates, as the control target point, a point closest to the host vehicle and having the smallest curvature radius in front of the host vehicle according to the road shape detected by the detection unit. The target vehicle speed when passing through the control target point is calculated based on the radius of curvature in the vehicle, and the target deceleration of the host vehicle is calculated based on the calculated target vehicle speed, the distance to the control target point, and the current vehicle speed. Then, when the target deceleration is larger than a predetermined deceleration start threshold, it is determined that the host vehicle is in a deceleration timing at which deceleration should be started.
Thereby, the deceleration timing which the own vehicle should decelerate can be judged easily.

(3) The correction means sets a correction start threshold smaller than the deceleration start threshold, and starts the correction when the target deceleration becomes larger than the correction start threshold.
Thereby, the operation reaction force with respect to the acceleration / deceleration operation of the driving can be controlled in the acceleration promoting direction at a time point before the deceleration timing.
(4) The correction means increases the correction amount in the deceleration promotion direction with respect to the operation reaction force as the difference between the target deceleration and the correction start threshold value is larger.
Accordingly, the driver can grasp how much the vehicle should decelerate now from the magnitude of the pedal reaction force.

(5) A deceleration control means for decelerating the vehicle at the deceleration timing determined by the determination means is provided.
Thus, before entering the curve, the vehicle can be surely decelerated so that the approach speed is suitable for the curve.
(6) The correction means increases the timing difference for starting the correction with respect to the deceleration timing as the host vehicle speed increases.
As a result, when the vehicle is traveling at a high speed, the driver can be urged to perform a deceleration operation with a sufficient margin before entering the curve, thereby giving the driver a sense of security.

(7) The correction unit changes a timing difference at which the correction is started with respect to the deceleration timing according to a road surface gradient.
Thereby, it is possible to prompt the driver to perform a deceleration operation at an appropriate timing according to the road surface gradient.
(8) The correction means increases the timing difference for starting the correction with respect to the deceleration timing as the descending slope is larger.
As a result, in situations where the vehicle speed is likely to increase, such as downhill roads, the driver can be urged to decelerate with sufficient margin before entering the curve, giving the driver a sense of security. it can.

(9) The correction means reduces the timing difference at which the correction is started with respect to the deceleration timing as the ascending slope is larger.
As a result, in situations where the vehicle speed is likely to decelerate, such as downhill roads, the driver is prevented from unnecessarily urging the deceleration operation, and the driver does not feel uncomfortable.
(10) The correction unit limits a timing difference at which the correction is started with respect to the deceleration timing to a predetermined range.
As a result, it is possible to prevent the reaction force correction from being unnecessarily accelerated when the vehicle speed is too high or the descending slope is too large. On the other hand, although the vehicle speed is low or the ascending slope is large and the vehicle is in a situation where it is easy to decelerate, the timing difference for starting the reaction force correction with respect to the deceleration timing becomes too small, and the difference is The situation that it cannot recognize can be prevented.

(11) The driving operation element includes an accelerator operation element, the reaction force control unit applies an operation reaction force to the accelerator operation element according to a driver's accelerator operation, and the correction unit includes the accelerator operation element. The operation reaction force against the child is increased and corrected.
As a result, the driver can be prompted to perform a deceleration operation that loosens the accelerator operation.
(12) The driving operation element includes a brake operation element, the reaction force control unit applies an operation reaction force to the brake operation element in accordance with a driver's brake operation, and the correction unit includes the brake operation element. Reduce the operation reaction force against the child.
As a result, the driver can be prompted to perform a deceleration operation that enhances the brake operation.

(13) The deceleration timing at which the host vehicle should start decelerating is determined according to the road shape ahead of the host vehicle course, and the operation reaction force for driving acceleration / deceleration operation is decelerated before the determined deceleration timing. Control in the direction of promotion.
As described above, by controlling the reaction force to the acceleration / deceleration operation of the driving in the deceleration acceleration direction at a time before the deceleration timing, the driver is effectively notified that the vehicle needs to be decelerated. be able to.

(14) A target vehicle speed at which a point closest to the host vehicle and having the smallest radius of curvature is calculated as a control target point in front of the host vehicle path, and the vehicle passes through the control target point based on the calculated radius of curvature at the control target point. When the target deceleration of the host vehicle is calculated based on the calculated target vehicle speed, the distance to the control target point, and the current vehicle speed, and the target deceleration is greater than a predetermined deceleration start threshold Then, it is determined that it is the deceleration timing at which the host vehicle should start deceleration.
Thereby, it is possible to easily determine the deceleration timing at which the host vehicle should start deceleration.

DESCRIPTION OF SYMBOLS 1 Brake pedal 2 Brake booster 5 Brake actuator 10 Controller 20 Driving force control device 32 Navigation device 34 Accelerator pedal 35 Reaction force motor

Claims (8)

A driving operator that is accelerated / decelerated by the driver, and a reaction force control means that applies an operating reaction force to the driving operator in accordance with the driver's acceleration / deceleration operation;
Detection means for detecting a road shape ahead of the host vehicle, determination means for determining a deceleration timing that is a timing at which the own vehicle should start deceleration according to the road shape detected by the detection means, and the determination means Correction means for starting correction in the deceleration acceleration direction for the operation reaction force at a time prior to the deceleration timing, and deceleration control means for decelerating the vehicle at the deceleration timing determined by the determination means,
The determination means calculates, as a control target point, a point closest to the host vehicle and having the smallest curvature radius in front of the host vehicle according to the road shape detected by the detection unit, and the curvature radius at the calculated control target point The target vehicle speed when passing the control target point is calculated based on the target vehicle speed, the target vehicle speed is calculated based on the calculated target vehicle speed, the distance to the control target point, and the current vehicle speed, When the target deceleration is larger than a predetermined deceleration start threshold, it is determined that it is a deceleration timing at which the host vehicle should start deceleration,
The correction means sets a correction start threshold smaller than the deceleration start threshold, and starts the correction when the target deceleration becomes larger than the correction start threshold,
The correction means increases the correction amount in the deceleration acceleration direction with respect to the operation reaction force as the difference between the target deceleration and the correction start threshold value is larger.
The driving support device according to claim 1, wherein the correction unit increases the timing difference at which the correction starts with respect to the deceleration timing as the host vehicle speed increases . The driving support device according to claim 1 , wherein the correction unit changes a timing difference at which the correction is started with respect to the deceleration timing according to a road surface gradient. The driving support device according to claim 2 , wherein the correction unit increases a timing difference at which the correction is started with respect to the deceleration timing as the descending slope is larger. 4. The driving support device according to claim 2 , wherein the correction unit decreases a timing difference at which the correction is started with respect to the deceleration timing as the ascending gradient increases. 5. Wherein the correction means, the driving support apparatus according to a timing difference for starting the correction for the deceleration timing, to any one of claims 1 to 4, characterized in that to limit to a predetermined range. The driving operator includes an accelerator operator,
The reaction force control means provides an operation reaction force to the accelerator operation element according to a driver's accelerator operation,
The driving support apparatus according to any one of claims 1 to 5 , wherein the correction unit increases and corrects an operation reaction force with respect to the accelerator operator. The driving operator includes a brake operator,
The reaction force control means provides an operation reaction force to the brake operator according to a driver's brake operation,
The driving support apparatus according to any one of claims 1 to 6 , wherein the correction unit corrects the operation reaction force with respect to the brake operator to decrease. The deceleration timing at which the host vehicle should start decelerating is determined according to the shape of the road ahead of the host vehicle's path, and the reaction force to the acceleration / deceleration operation of the driving is set in the deceleration acceleration direction at a time before the determined deceleration timing. Correct, decelerate the vehicle at the deceleration timing,
When determining the deceleration timing, according to the road shape, a point closest to the host vehicle and having the smallest radius of curvature is calculated as a control target point in front of the host vehicle, and the calculated radius of curvature at the control target point is calculated. Based on the calculated target vehicle speed, the distance to the control target point, and the current vehicle speed, the target deceleration of the host vehicle is calculated based on the target vehicle speed. When the deceleration is larger than a predetermined deceleration start threshold, it is determined that it is a deceleration timing at which the host vehicle should start deceleration,
A correction start threshold smaller than the deceleration start threshold is set, and when the target deceleration becomes larger than the correction start threshold, the correction is started,
When performing the correction, the larger the difference between the target deceleration and the correction start threshold, the larger the correction amount in the deceleration acceleration direction for the operation reaction force, and the higher the host vehicle speed, the more the deceleration timing is set. A driving support method characterized by increasing a timing difference at which the correction is started .

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