JP2010137647A - Drive assisting device and drive assisting method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To assist the drive of a driver so as to make vehicle speed when entering an intersection proper. <P>SOLUTION: It is determined whether there is speed reducing intention in entering the intersection X or not. When there is the speed reducing intention, first set vehicle speed is selected, and when there is no speed reducing intention, second set vehicle speed lower than the first set vehicle speed is selected. The vehicle speed V when an own vehicle enters the intersection X is limited to a speed not higher than the selected set vehicle speed. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a driving support device and a driving support method that support driving of a driver when entering an intersection.

As driving assistance at the time of passing an intersection, there is a technique described in Patent Document 1, for example. In this prior art, an intersection control system that controls intersection traffic at an intersection without a traffic light detects a vehicle that has entered within a predetermined distance range from the intersection. And position information and vehicle state information are acquired from each detected vehicle, and the crossing possibility of each vehicle and the priority of intersection passage are determined. Based on the determination, deceleration control of each vehicle is executed so that each vehicle can pass with minimum deceleration.
JP 2007-141145 A

In the prior art, the limit vehicle speed is uniquely set even when entering the intersection.
However, the vehicle speed required by the driver differs depending on whether the driver has noticed the intersection beforehand or not because the vehicle speed at which the safety in the intersection can be confirmed is different. For this reason, in the said prior art, a drivability may be impaired.
This invention is made paying attention to such a point, and makes it a subject to assist a driver | operator's driving | operation so that the vehicle speed at the time of approaching an intersection may turn into an appropriate speed.

  In order to solve the above problems, the present invention sets a vehicle speed limit based on a distance to a target position when entering an intersection. Based on the vehicle speed limit, the distance to the target position, and the vehicle speed of the host vehicle, it is determined whether or not there is an intention to decelerate when entering the intersection. When it is determined that there is an intention to decelerate as the vehicle speed of the host vehicle when entering the intersection, the first set vehicle speed is selected, and when it is determined that there is no intention to decelerate, The lower second set vehicle speed is selected, and the vehicle speed of the host vehicle is limited to be equal to or lower than the selected set vehicle speed.

  According to the present invention, the vehicle speed of the difference entering the intersection can be changed depending on whether the driver has noticed the intersection in advance or not, and the driver's driving can be supported without impairing drivability. It becomes possible to do.

(First embodiment)
Next, a first embodiment of the present invention will be described with reference to the drawings.
FIG.1 and FIG.2 is a typical schematic diagram which shows the vehicle structure of this embodiment. Note that the vehicle 1 shown in FIG. 1 is an electric vehicle. However, a drive system such as an engine-driven vehicle or a hybrid vehicle may be used. That is, the driving method of the vehicle 1 is not limited.
Brake devices 11F and 11R are mounted on the wheels 2F and 2R of the vehicle 1, respectively. The braking devices 11F and 11R apply a brake pressure corresponding to a command from the controller 4 to the wheels 2F and 2R. The braking devices 11F and 11R may be hydraulic or electric.
Each wheel is provided with wheel speed sensors 3F and 3R. The wheel speed sensors 3 </ b> F and 3 </ b> R detect the wheel speed of each wheel and output the detected value to the controller 4.

Reference numeral 5 denotes a brake pedal, and reference numeral 6 denotes a brake operation amount detection sensor. The brake operation amount detection sensor 6 detects the stroke amount of the brake pedal 5 as a brake operation amount BP and outputs it to the controller 4.
Here, at least one of the front wheel 2F and the rear wheel 2R is a drive wheel. The driving wheel is driven to rotate by a driving force from a driving source such as a motor. The drive source outputs torque corresponding to the drive force command from the controller 4 to the drive wheels. The controller 4 calculates a driving force command according to the accelerator opening of the accelerator pedal 7. Reference numeral 7 denotes an accelerator pedal, and reference numeral 8 denotes an accelerator pedal operation amount detection sensor.

A stereo camera 9 is mounted on the vehicle 1. The stereo camera 9 captures the road situation ahead of the vehicle 1 and outputs information on the road ahead to the controller 4. In FIG. 1, the case where the stereo camera 9 is installed in the upper part of a windshield is illustrated. The imaging unit of the stereo camera 9 may be composed of a CCD or the like.
The vehicle 1 is equipped with a navigation system 10. As shown in FIG. 3, the navigation system 10 includes a navigation control unit 10A, a road information database 10B, a reception unit 10C, a voice input / output unit 10D, a display unit 10E, and an operation unit 10F. Map data and the like are recorded in the road information database 10B. As the receiving unit 10C, for example, a GPS receiver, a beacon receiver, an FM multiplex receiver, or the like may be employed. The voice input / output unit 10D outputs information such as route guidance messages and warnings by voice. The display unit 10E outputs auxiliary information in the vicinity of an intersection or the like in the form of an image.

  The navigation control unit 10A calculates position information of the host vehicle 1 based on the signal acquired by the receiving unit 10C. Based on the calculated position information and data in the road information database 10B, road information is output through the voice input / output unit 10D and the display unit 10E. Further, the navigation control unit 10 </ b> A detects information on whether there is an intersection in the traveling direction of the host vehicle 1 and whether there is a traffic light at the intersection, and outputs the detected information to the controller 4.

As shown in FIG. 4, the controller 4 includes a drive controller 4A, a braking controller 4B, and a controller body 4C.
The drive controller 4A calculates a driving force based on an accelerator stroke amount and the like operated by the driver, and controls a motor that is a driving source so as to obtain the calculated driving force.
The braking controller 4B controls the braking force of each wheel so that the braking amount corresponds to the braking pressure control amount P ^* from the controller body 4C.

  The controller main body 4C inputs the road information ahead from the camera 9, the wheel speed detected by the wheel speed sensors 3F and 3R, and the brake operation amount of the driver. Then, the brake pressure command amount for braking the vehicle 1 is calculated, and the calculated brake pressure command amount is output to the brake controller 4B. Thereby, the control of the vehicle 1 is executed. The controller body 4C calculates the average value of the wheel speeds detected by the wheel speed sensors 3F and 3R of each wheel as the vehicle speed V (unit: m / s).

Next, the processing of the controller body 4C will be described with reference to FIG. The control process of the controller main body 4C operates and executes every predetermined sampling period.
First, in step S10, it is determined whether or not there is an intersection X without a traffic signal in the traveling direction of the vehicle 1 as shown in FIG. The detection of the intersection X is determined, for example, by whether or not the intersection X exists between the position of the bumper 1a at the tip of the host vehicle 1 and a position 45.0 m away. Note that 45.0 m means that the vehicle speed is about 10 km / h immediately before entering the intersection X when decelerating at a constant speed of 3.0 m / s ² from the state of traveling at a maximum vehicle speed of 60 km / h on ordinary roads. Is the distance.

When it is determined that there is an intersection X without a traffic signal, the process proceeds to step S20. If not, return.
Whether there is an intersection X without a traffic light is determined based on information from the navigation system 10. Note that whether or not there is an intersection X without a traffic light may be determined based on information from the stereo camera 9. That is, an image in front of the vehicle body taken by the stereo camera 9 may be subjected to image processing to determine whether there is an intersection road ahead of the host vehicle 1 and whether there is a traffic light at the intersection X.

In step S20, it is determined whether the intersection X without the traffic signal detected in step S10 is the priority road or the non-priority road on the own lane (the road on which the own vehicle is traveling). When the own lane is a non-priority road, the process proceeds to step S30. On the other hand, when the own lane is a priority road, it returns.
Whether the own lane is a priority road or a non-priority road is determined as follows. That is, based on the information on the priority road / non-priority road recorded in the road information database 10B and the position and speed (traveling direction) of the own vehicle 1 with respect to the detected intersection X, whether the own lane is a priority road or a non-priority road. It is determined whether.

  Whether the own lane is a priority road or a non-priority road may be determined by information from the stereo camera 9. That is, an image of the front of the vehicle taken by the stereo camera 9 may be subjected to image processing, the width of the intersection road intersecting the own lane and the width of the own lane road may be compared, and the narrow road side may be determined as a non-priority road. . Similarly, whether or not there is a display such as “stop” on the road in front of the intersection X and whether or not there is a sign indicating a temporary stop is determined by image processing, so that the own lane is a priority road It may be determined whether the road is a non-priority road.

In step S30, a target position T is set based on the information on the intersection X, and two set vehicle speeds at the target position T are set.
Here, as shown in FIG. 6, a boundary between the road on the own lane and the road on the intersection side is set as a target position T when the own vehicle 1 enters the intersection X. The target position T may be slightly in front of the boundary or may be slightly on the cross road side. The near side is preferable to the cross road side. FIG. 6 schematically shows an example of the intersection X without a traffic light. Here, step S30 constitutes a target position setting means.

  The two set vehicle speeds are the first set vehicle speed Vs1 and the second set vehicle speed Vs2. The second set vehicle speed Vs2 is a vehicle speed value lower than the first set vehicle speed Vs1, and is, for example, a vehicle speed value that is half of the first set vehicle speed Vs1. For example, the first set vehicle speed Vs1 is set to a vehicle speed during slow traveling (for example, 5 km / h) at which the host vehicle can stop in a short time. In this case, the second set vehicle speed Vs2 is set to a vehicle speed value (2.5 km / h) that is half the first set vehicle speed Vs1, for example.

In step S40, a distance L (unit: m) to the intersection X is detected.
The distance L to the target position T is the distance L from the front end of the front bumper 1a in the current vehicle 1 to the target position T. The distance L to the target position T has a positive value on the intersection X side and a negative value on the near side of the intersection X.
The distance L to the target position T is calculated based on the current position of the host vehicle 1 of the navigation system 10 and road data. Alternatively, an image in front of the vehicle body captured by the stereo camera 9 may be subjected to image processing, and the distance L from the intersection X position in the image signal to the target position T may be calculated.

In step S50, a limit vehicle speed Vlim (L) is set.
In the present embodiment, the limit vehicle speed Vlim (L) (unit: km / h) is set as shown in Expression (1), with the distance L (unit: m) to the target position T as a variable.
Vlim (L) = 3.6 × √ {2αlim · L + (Vth ÷ 3.6) ² } (1)
The vehicle speed limit Vlim obtained by equation (1) is a value that can be reduced to Vth (unit: km / h) at this boundary if the vehicle speed is reduced by αlim. In this embodiment, 3 (m / s ² ) is set for αlim, and 10 (km / h) is set for Vth. This Vlim is shown in FIG. In FIG. 7, the distance L to the target position T that is the boundary between the intersection X and the intersection road is taken on the horizontal axis.

This αlim is preferably set to the maximum deceleration that the driver can take when passing through such an intersection X.
As specific αlim setting means, a method of recording the deceleration when the driver passes the intersection X that needs to be temporarily stopped and extracting the maximum deceleration from the recorded deceleration can be considered. In addition, the driving behavior when passing through the intersection X where a plurality of drivers need to be temporarily stopped may be recorded, and the maximum value of the deceleration may be taken.

When the vehicle speed limit Vlim (L) is set to be high as described above, when the driver passes safely, the deceleration control does not intervene in the operation of the driver, and further improvement in drivability can be expected.
In step S60, it is determined whether or not the distance L to the target position T is smaller than zero. If the distance L to the target position T is smaller than 0, the process proceeds to step S70. When the distance L is 0 or more, the process proceeds to step S84.

In step S70, an assist brake pressure control amount P (unit: bar) for preventing the vehicle speed V of the host vehicle from exceeding Vlim (L) from the vehicle speed V of the host vehicle and the limit vehicle speed Vlim (L) set in step S50. Is obtained as shown in equation (2).
P = max [{(V−Vlim (L)) × Pg}, 0] (2)
Pg in the equation (2) is a proportional gain, and in this embodiment, 25 is set as the proportional gain Pg. In obtaining the assist brake pressure control amount P, it is not necessary to perform proportional control as shown in Equation (2). In order to converge to Vlim (L) etc. without deviation, the amount of assist brake pressure is controlled by using proportional + integral control (PI control) or using a controller that can model and take into account the delay of the hydraulic brake. It is even better to find P.

In step S84, it is determined whether or not it is the moment when the distance L between the intersection X and the target position T of the intersection road is 0 or more in the current control cycle. If the distance L is 0 or more, the process proceeds to step S85. On the other hand, if the distance L is already 0 or more in the previous control cycle, the process proceeds to step S90.
In step S85, a set vehicle speed Vtar (unit: km / h) which is the final deceleration target vehicle speed is selected and set.

In the present embodiment, when the vehicle speed V of the host vehicle at the moment when the distance L between the intersection X and the target position T of the intersection road is 0 or more is 80% or more of the limit vehicle speed Vlim (0). The driver is not aware of the intersection X and determines that there is no intention to decelerate. Then, the second set vehicle speed Vs2 is selected, and the second set vehicle speed Vs2 is set to Vtar.
On the other hand, if the vehicle speed V of the host vehicle is less than 80% of the limit vehicle speed Vlim (0), the driver is aware of the intersection X and determines that there is an intention to decelerate. Then, the first set vehicle speed Vs1 is selected, and the first set vehicle speed Vs1 is set to Vtar.

In step S90, when the vehicle speed V of the host vehicle exceeds the set vehicle speed Vtar determined in step S80, an assist brake pressure control amount P that can be immediately decelerated to Vtar or less is obtained as in equation (3).
P = max [{(V−Vtar) × Pg2}, 0] (3)
Pg2 in the equation (3) is a proportional gain, and in this embodiment, 100 is set as the proportional gain Pg2. In determining the assist brake pressure control amount P, the proportional control as shown in Expression (3) may not be used. It is better to use a controller that can model and take into account the delay of the hydraulic brake or gain scheduling the proportional gain Pg2 so that the vehicle speed V can be reduced to Vtar or less quickly and without overshoot. .

In step S100, a brake pressure control amount P ^* is obtained.
First, the brake pressure Pd (unit: bar) generated by the driver's brake operation amount BP is obtained with reference to the map of FIG.
Next, the brake pressure control amount P ^* (unit: bar) of each wheel is obtained according to the following equation (4) and output to the braking controller 4B.
P ^* = Pd + P (4)
In the map of FIG. 8, the brake pressure Pd generated by the driver's brake operation amount BP may be measured and mapped in advance and stored.
Finally, in step S110, whether or not the two conditions that the distance L to the target position T is not less than 0 and the vehicle speed V of the host vehicle is not more than the set vehicle speed Vtar defined in step S85 are satisfied. To determine. If it is determined that the above two conditions are satisfied, it is determined that the vehicle has entered the intersection X safely, and the control when entering the intersection X is terminated. If the above two conditions are not satisfied, the process returns to step S40.

(Action / Operation)
The driving assistance of the present embodiment starts processing when it is detected that there is an intersection X in front of the vehicle 1, for example, 45m ahead. And if the intersection X ahead is an intersection X without a traffic light and the lane of the own vehicle 1 is a non-priority road, it is determined whether or not the vehicle speed limit is executed until the vehicle enters the intersection X.
At this time, when the vehicle speed V of the host vehicle 1 is smaller than the limit vehicle speed Vlim, the deceleration control is not performed. That is, no control intervention is performed to limit the vehicle speed.
On the other hand, when the vehicle speed of the host vehicle 1 is larger than the limit vehicle speed Vlim, the deceleration control is executed so that the upper limit of the vehicle speed of the host vehicle 1 becomes the limit vehicle speed Vlim.
For example, as shown by B1 in FIG. 7, it is assumed that the driver is driving loosely and does not notice the intersection X, and the vehicle speed V of the host vehicle approaches the intersection X with a constant speed. At this time, in this embodiment, the upper limit of the vehicle speed is limited by the limit vehicle speed Vlim (L).

  In the example of B1, since the vehicle speed V becomes equal to or higher than the limit vehicle speed Vlim (L) at the point (i), the vehicle speed is limited at the limit vehicle speed Vlim (L). In the example of B1, the case where the driver does not notice the intersection X and does not perform a sufficient brake operation even if the vehicle is limited by the limited vehicle speed Vlim (L) is shown. In the case of B1, it is determined that the driver does not intend to decelerate, and the deceleration control is performed to the second set vehicle speed Vs2 or less at the target position T that is a boundary with the intersection road. As a result, the time margin that the driver can check left and right is expanded, and safety is improved.

Next, a case will be described in which it is assumed that the driver is aware of the intersection X and is driving such that the vehicle speed V is reduced and the vehicle passes through the intersection X as in B2.
In the case of B2, the vehicle approaches the intersection X with the vehicle speed V of the host vehicle being lower than the limit vehicle speed Vlim, and also enters the intersection X at the target position T with the vehicle speed V being lower than the first set vehicle speed Vs1. is doing. For this reason, the braking control does not intervene in the driver's deceleration operation. For this reason, it does not give the driver a sense of incongruity.

  However, when the vehicle speed V is less than 80% of the limit vehicle speed Vlim (0) at the target position T and the vehicle speed V is higher than the first set vehicle speed Vs1, the vehicle speed is less than Vs1 after passing through the target position T. Deceleration control is performed so that If the vehicle speed is 80% or more of the limit vehicle speed Vlim (0) at the target position T, deceleration control is performed so that the vehicle speed becomes Vs2 or less after passing through the target position T.

In this way, by determining the driver's intention to decelerate from the vehicle speed V of the host vehicle and the limit vehicle speed Vlim (L), by changing the vehicle speed to be limited at the target position T, which is the boundary with the intersection road, and optimizing it. It can be expected that safety and driving performance can be improved at the same time.
Here, the camera 9 or the navigation system 10 constitutes a distance detection means. The wheel speed sensors 3F and 3R constitute vehicle speed detection means.
Step S50 constitutes a limit vehicle speed setting means. Steps S84 and S85 constitute deceleration intention estimation means and vehicle speed selection means. Steps S70 and S90 constitute vehicle speed limiting means.
The limit vehicle speed Vlim constitutes an upper limit vehicle speed.

(Effect of this embodiment)
(1) The deceleration intention estimation means determines whether or not there is a deceleration intention when entering the intersection based on the vehicle speed of the host vehicle and the limit vehicle speed. The vehicle speed selection means selects the first set vehicle speed when the deceleration intention estimation means determines that there is a deceleration intention, and when the deceleration intention estimation means determines that there is no deceleration intention, A second set vehicle speed lower than the set vehicle speed of 1 is selected. When it is determined that the vehicle speed of the host vehicle is greater than the set vehicle speed selected by the vehicle speed selection unit, the vehicle speed limiting unit performs deceleration control so that the vehicle speed of the host vehicle is equal to or lower than the set vehicle speed selected by the vehicle speed selection unit.
Thus, the set vehicle speed when entering the intersection X is changed according to the driving situation of the driver. Specifically, when the driver notices the intersection X and estimates that there is an intention to decelerate, the set vehicle speed is set to the first set vehicle speed. This suppresses unnecessary vehicle speed restriction intervention.

On the other hand, when it is estimated that the driver is not aware of the intersection X, the set vehicle speed at the target position T is set to a low second set vehicle speed. Thereby, the time margin which a driver | operator can confirm the safety | security of the intersection X can be expanded now.
As described above, it is possible to set the vehicle speed when entering the intersection X to an appropriate speed advantageous for checking the situation of the intersection X according to the driving situation of the driver while suppressing unnecessary vehicle speed limit control intervention. It becomes. That is, it is possible to support the driver at an appropriate speed while suppressing the troublesomeness to the driver when entering the intersection X as much as possible and ensuring the driving performance of the driver.

(2) The deceleration intention estimation means determines that there is an intention to decelerate when the vehicle speed of the host vehicle is less than the limit vehicle speed, and determines that there is no intention of deceleration when the vehicle speed of the host vehicle is equal to or greater than the limit vehicle speed. First determination means.
By appropriately setting the vehicle speed limit, the driver's intention to decelerate can be determined appropriately. As a result, the vehicle speed when entering the intersection can be controlled to an appropriate vehicle speed.

(3) The restricted vehicle speed setting means sets the restricted vehicle speed to be lower as the distance to the target position is smaller.
As a result, the closer to the intersection, the easier the deceleration control intervention is carried out, and the driving is supported so that the driver can secure a time margin for confirming the safety of the intersection road.
As described above, it is possible to set the vehicle speed when entering the intersection X to an appropriate speed that is advantageous for confirming the situation of the intersection X and the like while suppressing unnecessary vehicle speed limit control intervention.

(4) The vehicle speed limiting means limits the upper limit value of the vehicle speed of the host vehicle to the upper limit vehicle speed or less based on the distance to the target position.
As a result, even when the driver is not aware of the intersection, the vehicle speed can be kept below the upper limit vehicle speed.
In particular, by setting the upper limit vehicle speed as it approaches the target position T, the driver can gradually decelerate toward the target position T even if the driver is not aware of the intersection X. That is, since driving assistance can be provided so as to guide the vehicle speed to the set vehicle speed toward the target position T, it is not necessary to perform large deceleration control before the intersection X.

(5) The vehicle speed restriction by the vehicle speed restriction means is performed when the own lane is a non-priority road.
When the own lane is a non-priority road, it is necessary to reduce the vehicle speed or temporarily stop when entering the intersection X. However, there is no need to limit the vehicle speed when the own lane is a non-priority road.
That is, even when the vehicle enters the intersection X, if it is a priority road, it is possible to prevent the vehicle speed from being restricted. As a result, unnecessary vehicle speed restriction can be suppressed.

(Modification)
(1) Even a vehicle that is controlled by a motor or a mechanical brake can be applied as long as the vehicle is equipped with means for controlling the braking force independently of the driver's operation.
(2) In the above-described embodiment, the stereo camera 9 and the car navigation system 10 are used together. However, the present embodiment can be realized by using only the stereo camera 9 or the car navigation system 10. .
(3) Further, the stereo camera 9 and the car navigation system 10 are provided with a sensor / infrastructure system described in, for example, Japanese Patent Application Laid-Open No. 2004-86363, which can realize the functions required in the present embodiment. In the case of being present, it can be applied in place of the stereo camera 9 and the car navigation system 10.

(4) Further, the first set vehicle speed Vs1 and the second set vehicle speed Vs2 smaller than the first set vehicle speed Vs1 may be changed depending on the skill of the driver, the situation of the intersection X, and the like.
For example, whether the visibility of the intersection X is good or not is determined, and the first set vehicle speed Vs1 is set larger as the area where the driver can confirm the intersection road intersecting with the own lane increases. Further, when the above-mentioned area where the driver can confirm the cross road becomes small, the second set vehicle speed Vs2 is set to be small. The area where the driver can confirm the crossing road intersecting with the own lane is determined based on the position of the own vehicle 1 and the information on the shielding on the side of the own vehicle 1.
Further, the first set vehicle speed Vs1 and the second set vehicle speed Vs2 may be adjusted according to the history of behavior when the driver moves to the intersection X.

(5) The above embodiment is an example when the target position T is set as the determination position for the intention of deceleration. The determination position of the intention to decelerate may be set at a position before the target position T. In this case, the set vehicle speed selected near the target position T can be obtained.
(6) Moreover, it is not necessary to make the upper limit speed coincide with the limit vehicle speed Vlim. The upper limit speed may be set to a value larger than the limit vehicle speed Vlim by a predetermined vehicle speed value.
(7) In the deceleration intention estimation means of the above embodiment, the intention of deceleration is determined based on whether or not the vehicle speed V of the host vehicle is 80% or more of the limit vehicle speed Vlim (0) at the target position T. However, it is not limited to this. The intention of deceleration may be determined based on whether or not the vehicle speed V of the host vehicle is equal to or higher than the limit vehicle speed Vlim at the target position T.

(Second Embodiment)
Next, a second embodiment of the present invention will be described with reference to the drawings. In addition, about the apparatus similar to the said embodiment, the same code | symbol is attached | subjected and demonstrated.
The vehicle configuration, navigation system, and controller of the vehicle used in the description of the second embodiment are the same as those illustrated in the description of the first embodiment, and are as shown in FIGS.
The process of the controller 4 in 2nd Embodiment is demonstrated with reference to FIG. The control process of the controller 4 operates and executes every predetermined sampling period as in the first embodiment.

The processing in steps S10 to S40 is the same as the processing in the first embodiment. Then, after step S40, the process proceeds to step S53.
In step S53, a limit vehicle speed Vlim (L) is set.
In the present embodiment as well, the vehicle speed limit Vlim (L) (unit: km / h) is set as the equation (1) with the distance L (unit: m) to the target position T as a variable, as in the first embodiment. Set.
Vlim (L) = 3.6 × √ {2αlim · L + (Vth ÷ 3.6) ² } (1)
However, α (lim) is set to 3 (m / s ² ). Also, the first set vehicle speed Vs1 (= 5.0 km / h) is set as the value of Vth. This Vlim (L) is shown in FIG.

Next, in step S55, the second transition vehicle speed Vlim2 (L) is set.
The second transition vehicle speed Vlim2 (L) (unit: km / h) is set as shown in Expression (5), with the distance L (unit: m) to the target position T as a variable. The second transition vehicle speed Vlim2 (L) is a vehicle speed when the vehicle is decelerated by αmax so as to be the second set vehicle speed Vs2 at the target position T.
Vlim2 (L) = 3.6 × √ {2αmax · L + (Vs2 ÷ 3.6) ² } (5)
This Vlim2 (L) is also shown in FIG. Αmax in equation (5) is a larger value than αlim in equation (1). In the present embodiment, 6 (m / s ² ) is set as αmax. Then, the point where the limit vehicle speed Vlim (L) and the second transition vehicle speed Vlim2 (L) set in step S53 intersect is defined as a point (A) as shown in FIG. 10, and the intersection X and the target position T of the intersection road are reached. Is La (unit: m). The point (A) is the determination position for the intention to decelerate.

Next, in step S65, it is determined whether the distance L to the target position T is smaller than La. If the distance L to the target position T is smaller than La, the process proceeds to step S70. If the distance L is greater than or equal to La, the process proceeds to step S84.
The process in step S70 is the same as the process in the first embodiment.
Next, in step S84, it is determined whether or not the own vehicle has passed the point (A). That is, it is determined whether or not it is the moment that the point (A) at which the distance L to the target position T is La in the current sampling cycle has passed. If it is determined that it has passed, the process proceeds to step S85. Otherwise, the process proceeds to step S95.

Here, in the present embodiment, the sampling period in which the distance L is smaller than Lb in the previous sampling period and the distance L is equal to or greater than Lb in the current sampling period is determined as the moment of passing.
In step S85, the set vehicle speed is selected, and the transition vehicle speed Vtra (L) (unit: km / h) after reaching the point (A) is set.

In the present embodiment, when the vehicle speed V of the host vehicle is equal to or higher than the limit vehicle speed Vlim (L) at the moment of passing through the point (A), the driver is not aware of the intersection X and has no intention of deceleration. Or, it is determined as insufficient. In this case, the second set vehicle speed Vs2 is selected as the set vehicle speed. Then, the second transition vehicle speed Vlim2 (L) that decelerates to the second set vehicle speed Vs2 at the target position T is set to the transition vehicle speed Vtra (L).
On the other hand, if the vehicle speed V of the host vehicle is less than the limit vehicle speed Vlim (L) at the moment of passing through the point (A), the driver recognizes the intersection X and determines that the vehicle is intended to decelerate. In this case, the first set vehicle speed Vs1 is selected as the set vehicle speed. Then, the limit vehicle speed Vlim (L) as the first transition vehicle speed is set to the transition vehicle speed Vtra (L).

In step S95, when the vehicle speed V of the host vehicle exceeds the transition vehicle speed Vtra (L) set in step S85, an assist brake pressure control amount P that can be immediately decelerated to Vtra (L) or less is expressed by equation (6). Ask.
P = max [{(V−Vtra (L)) × Pg3}, 0] (6)
Pg3 in the equation (6) is a proportional gain. In this embodiment, 50 is set as the proportional gain Pg3. In determining the assist brake pressure control amount P, the hydraulic brake delay may be modeled so that the vehicle speed V can be reduced to Vtar or less promptly and without overshoot, which does not have to be proportional control as in equation (6). It is even better to obtain a controller that can be taken into consideration or to schedule the proportional gain Pg2.
The processes in steps S100 and S110 are the same as those in the first embodiment.

(Operation / Action)
In the second embodiment, the driver's intention to decelerate is determined based on whether or not the vehicle is limited to a vehicle speed limit Vlim (L) or less before the intersection X. As a result, the driver's intention to decelerate is determined before the intersection X and the vehicle starts decelerating. When entering the intersection X, the first set vehicle speed Vs1 or the second set vehicle speed Vs2 is less than the appropriate set vehicle speed. Control to be

Moreover, the transition vehicle speed which decelerates continuously to the target position T in step S85 is set. By introducing this transition vehicle speed, the vehicle can be decelerated at the target position T without shock as compared with the first embodiment, and improvement in drivability can be expected.
Here, step S85 constitutes a vehicle speed selection means. Step S95 constitutes a deceleration intention estimation unit (first determination unit) and a vehicle speed limiting unit. The limit vehicle speed Vlim constitutes the first transition vehicle speed. The target position T constitutes the selected position.

(Effect of this embodiment)
In addition to the effects described in the first embodiment, the following effects are achieved.
(1) The deceleration intention estimation means determines a deceleration intention on the near side of the target position T. The vehicle speed limiting means limits the upper limit value of the vehicle speed so that the vehicle speed is equal to or lower than the set vehicle speed selected by the vehicle speed selection means at the target position or a selection position offset by a predetermined value before and after the target position.
This makes it possible to support driving so that the set vehicle speed selected according to the driving state is at or near the target position when entering the intersection X.

(2) A first transition vehicle speed that becomes lower as the position approaches the selected position and becomes the first set vehicle speed at the selected position is set. The vehicle speed limiting means limits the upper limit of the vehicle speed of the host vehicle to the first transition vehicle speed based on the distance detected by the distance detection means when the vehicle speed selection means selects the first set vehicle speed.
That is, when the first set vehicle speed is selected, the upper limit of the vehicle speed of the host vehicle is limited by the first transition vehicle speed that changes so as to approach the selected position.
As a result, it is possible to reliably support driving so that the first set vehicle speed selected according to the driving state is obtained at or near the target position when entering the intersection X.

(3) A second transition vehicle speed is set which becomes lower as approaching the selected position and becomes the second set vehicle speed at the selected position. The vehicle speed limiting means limits the upper limit of the vehicle speed of the host vehicle to the second transition vehicle speed based on the distance detected by the distance detection means when the vehicle speed selection means selects the second set vehicle speed.
That is, when the second set vehicle speed is selected, the upper limit of the vehicle speed of the host vehicle is limited by the second transition vehicle speed that changes so as to approach the selected position.
As a result, it is possible to reliably support driving so that the second set vehicle speed selected according to the driving state is obtained at or near the target position when entering the intersection X.

(4) The determination position is set at a position where the first transition vehicle speed and the second transition vehicle speed are the same speed or a difference between the first transition vehicle speed and the second transition vehicle speed is equal to or less than a predetermined value. Further, the first transition vehicle speed at the determination position is set as the determination vehicle speed.
As a result, even if the set vehicle speed at the target position T is changed, the upper limit value of the vehicle speed to be restricted can be changed smoothly.

(Modification)
(1) For the first transition vehicle speed (the limited vehicle speed Vlim in the second embodiment), as shown in FIG. 11, the profile from the point (A) that is the determination position of the intention to decelerate to the selected position (target position) May be set.
That is, the first transition vehicle speed is set to be the first set vehicle speed Vs1 before the selected position. As a result, the vehicle speed from the front to the selected position can be controlled to be constant.
That is, when the first selected vehicle speed Vs1 is selected, the vehicle speed V of the host vehicle can be set to a constant vehicle speed state when passing the target selection position. As a result, even if deceleration control is performed when entering the intersection X, it is possible to improve drivability when entering the intersection X and to relieve the driver of discomfort.

(2) For the second transition vehicle speed Vlim2, the profile from the point (A) that is the determination position of the intention to decelerate to the selected position (target position) vehicle speed may be set as shown in FIG.
That is, the second transition vehicle speed is set to be the second set vehicle speed before the selected position. As a result, the vehicle speed from the front to the selected position can be controlled to be constant.
That is, when the second selected vehicle speed Vs2 is selected, the vehicle speed V of the host vehicle can be set to a constant vehicle speed state when passing through the target selection position. As a result, even if deceleration control is performed when entering the intersection X, it is possible to improve drivability when entering the intersection X and to relieve the driver of discomfort.

(3) In the above embodiment, the determination position is set at the intersection of the first transition vehicle speed and the second transition vehicle speed Vlim2. Instead of this, the determination vehicle speed may be set at a position slightly deviated from the intersection of the first transition vehicle speed and the second transition vehicle speed Vlim2. The effect is similar.
(4) In the above embodiment, the selected vehicle speed is set at the target position T. Instead of this, the selected vehicle speed may be set at a position offset by a predetermined value before and after the target position.
In this case, it is preferable to set the front side of the target position T. If it does in this way, it becomes possible to improve the drivability at the time of approaching the intersection X, and to relieve a sense of incongruity to a driver because it becomes the target set vehicle speed rather than the target position T.

(5) Further, the determination position of the intention to decelerate may be set separately from the limit vehicle speed Vlim. The case where the determination position Vh is set separately as shown by the dashed-dotted line in FIG. 10 is illustrated. In this example, the determination position is set not with a single point but with a predetermined width. However, the determination vehicle speed Vh is set so as to decrease as it approaches the target position T.
When the determination position is given a width, it is possible to detect the case where the driver is not aware of the intersection X more reliably.
(6) Alternatively, a predetermined width may be provided corresponding to each determination speed with the intention of deceleration. In this way, hunting can be supported.

(Third embodiment)
Next, a third embodiment of the present invention will be described with reference to the drawings. In addition, about the apparatus similar to the said embodiment, the same code | symbol is attached | subjected and demonstrated.
The vehicle configuration, navigation system, and controller of the vehicle used in the description of the third embodiment are the same as those illustrated in the description of the first embodiment, and are as shown in FIGS.
Processing of the controller main body 4C in the third embodiment will be described with reference to FIG. The control process of the controller 4 operates and executes every predetermined sampling period as in the first embodiment.

The processes in steps S10 to S50 are the same as those in the first and second embodiments.
In step S56, the second transition vehicle speed Vlim2 (L) (unit: km / h) is set. The second transition vehicle speed Vlim2 (L) (km / h) is set as in equation (5), with the distance L (unit: m) to the target position T as a variable. The second transition vehicle speed Vlim2 (L) is a vehicle speed when the vehicle is decelerated by αmax so as to be the second set vehicle speed Vs2 at the target position T.
Vlim2 (L) = 3.6 × √ {2αmax · L + (Vs2 ÷ 3.6) ² } (5)

This Vlim2 (L) is displayed in FIG. Αmax in equation (5) is a larger value than αlim in equation (1). In the present embodiment, 6 (m / s ² ) is set as αmax. Then, a point where the limit vehicle speed Vlim (L) and the transition vehicle speed Vlim2 (L) set in step S50 intersect is a point (B) as shown in FIG. The distance from the target position T to the point (B) is Lb (unit: m). The same coordinates as the distance L are used, and Lb is a negative value.

In step S57, it is determined whether or not the current sampling cycle is the moment when it passes through the point (B) where the distance L to the target position T is Lb. If it is determined that the point has passed the point (B), the process proceeds to step S58, and if not, the process proceeds to step S60.
In the present embodiment, the sampling period in which the distance L is smaller than Lb in the previous sampling period and the distance L is greater than or equal to Lb in the current sampling period is determined as the moment of passing. Note that the distance L is a negative value before the target position T.
In step S58, it is determined whether or not the driver intends to decelerate. When it is determined that there is an intention to decelerate, 0 is set to the deceleration intention determination flag FL. On the other hand, when it is determined that there is no intention to decelerate, 1 is set to the deceleration intention determination flag FL. The driver's intention to decelerate is determined from the vehicle speed V and the acceleration α.

Next, a method for determining the driver's intention to decelerate will be described.
First, when it is determined that the vehicle has passed the point (B), if the vehicle speed V of the host vehicle is equal to or higher than the limit vehicle speed Vlim (L), the driver is not aware of the intersection and does not intend to decelerate, or It is determined that the deceleration is insufficient, and 1 is set to the deceleration intention determination flag FL.
On the other hand, when the host vehicle speed V when passing through the point (B) is smaller than the limit vehicle speed Vlim (L), the intention of deceleration is further determined as follows.
First, the required acceleration αth (unit: m / s ² ) is calculated based on the current vehicle speed V and the first set vehicle speed Vs1 as shown in equation (7).
αth = (Vs1 ² −V ² ) / (2L) (7)

The required acceleration αth is an acceleration that becomes the speed of the first set vehicle speed Vs1 at the target position T when the vehicle is decelerated or accelerated while maintaining the acceleration of αth from the current vehicle speed V.
Further, the current vehicle speed V is differentiated with respect to time to obtain the acceleration α (unit: m / s2).
Then, the current acceleration α (unit: m / s2) is compared with the required acceleration αth, and if α> αth, it is determined that there is no intention to decelerate or deceleration is insufficient, and the deceleration intention determination flag FL is set. 1 is set. On the other hand, if α ≦ αth, it is assumed that there is an intention to decelerate, and the deceleration intention determination flag FL is set to 0.

  An example of this determination will be described with reference to FIG. In the case of driving as shown by a broken line B4 in FIG. 13, if the vehicle is decelerated from the vehicle speed at the point (B) at a constant required acceleration αth, a broken line Vα is obtained. In this example, the slope of the broken line B4 (current acceleration α) exceeds the slope of the dashed line Vα (requested acceleration αth) at the point (B). That is, in the case of the broken line B4, the acceleration at the point (B) exceeds αth, it is determined that there is no intention of deceleration, and 1 is set in the deceleration intention determination flag FL.

Here, in addition to or instead of determining the driver's intention to decelerate (setting the deceleration intention determination flag FL), the driver's intention to decelerate (setting the deceleration intention determination flag FL) is performed as follows. May be.
For example, when the vehicle speed V of the host vehicle is greater than the second transition vehicle speed Vlim2 (L) in step S58, it is determined that there is no intention to decelerate or that the deceleration is insufficient, and the deceleration intention determination flag FL is set to 1. May be set. That is, the deceleration intention determination flag FL is also set when the vehicle speed V of the host vehicle becomes higher than the second transition vehicle speed Vlim2 (L).

In this case, in each determination of the above-mentioned two deceleration intentions, FL is set to 0 when the deceleration intention determination flag FL is 0 for both determinations, and FL is set to 1 otherwise. . That is, all the above-mentioned deceleration intention determination conditions are OR conditions, and the deceleration intention determination flag FL is set to 1 when one of the conditions is satisfied.
The determination when the vehicle speed V of the host vehicle becomes greater than the second transition vehicle speed Vlim2 (L) may be performed when the distance L becomes greater than Lb.

In FIG. 13, when the operation as indicated by the broken line B4 is performed, it is possible to determine that there is no intention to decelerate from the two-dot broken line at the point (C) as well as the point (B). Is set. The two-dot broken line is a deceleration waveform when the vehicle is decelerated at a constant required acceleration αth obtained from the vehicle speed V at the point (C).
The processing of steps S60 and S70 is the same as the flowchart of FIG. 2 of the first embodiment.
Next, in step S83, a set vehicle speed Vtar (unit: km / h) which is the final deceleration target vehicle speed is set.

In the present embodiment, if the deceleration intention determination flag FL set in step S58 is 1, it is determined that the driver has not noticed the intersection and has no intention of deceleration, and the second set vehicle speed Vs2 is set to Vtar.
On the other hand, when the deceleration intention determination flag FL is 0, the driver recognizes the intersection and determines that there is an intention to decelerate, and sets the first set vehicle speed Vs1 to Vtar.
The processes in steps S90, S100, and S110 are the same as those in the first embodiment.

(Operation / Action)
When the host vehicle enters the intersection, if the vehicle speed V of the host vehicle is higher than the limit vehicle speed Vlim at the point B, the driver is not aware of the intersection and does not intend to decelerate, and enters the intersection. The vehicle speed is controlled to be reduced below the second set vehicle speed.
Even if the vehicle speed V of the host vehicle is less than the limit vehicle speed Vlim at the point B, the current acceleration α of the host vehicle is greater than the required acceleration αth for achieving the first set vehicle speed Vs1 at the target position. Therefore, assuming that the driver is not aware of the intersection and does not intend to decelerate, the vehicle speed at the time of entering the intersection is reduced to the second set vehicle speed Vs2 or less.

Further, after passing the point B, when the vehicle speed V is equal to or higher than the second transition vehicle speed Vlim2, it is assumed that the driver has not noticed the intersection and does not intend to decelerate, and the vehicle speed when entering the intersection is set to the second speed. Decelerate control below vehicle speed.
As a result, the driver's intention to decelerate is more clearly determined from the distance L to the target position T, the vehicle speed V of the host vehicle, and the acceleration α of the host vehicle, and the road between the own lane and the road on the intersection side It becomes possible to change the vehicle speed limited at the boundary more appropriately.
Here, step S58 constitutes deceleration intention estimation means (second determination means).

(Effect of this embodiment)
In addition to the effects described in the first embodiment, the following effects are achieved.
(1) The deceleration intention estimation unit includes a second determination unit that determines the driver's intention to decelerate based on the distance detected by the distance detection unit, the vehicle speed of the host vehicle, and the acceleration of the host vehicle.
By determining based on the acceleration in addition to the intention to decelerate based on the limit vehicle speed, the driver's intention to decelerate can be determined more reliably.
(Modification)
(1) Only when it is determined that there is a deceleration intention in both determinations of the first determination unit and the second determination unit, it may be determined that there is a final intention of deceleration.
In this case, the limit vehicle speed Vlim used in the first determination means can be lowered.

(Fourth embodiment)
Next, a fourth embodiment according to the present invention will be described with reference to the drawings. Devices similar to those in the above embodiment will be described with the same reference numerals.
The basic configuration of this embodiment is the same as that of each of the above embodiments.
However, part of the processing of the controller body 4C is different.
Processing of the controller main body of the present embodiment will be described with reference to FIG.
The control process of the controller 4 operates and executes every predetermined sampling period as in the first embodiment.

Since the processes in steps S10, S20, S30, S40, S53, and S55 are the same as those in the second embodiment, a description thereof will be omitted. Here, the limit vehicle speed Vlim and the second transition vehicle speed Vlim2 are set to the same transition as in FIG.
When the process of step S55 ends, the process proceeds to step S59.
In step S59, it is determined whether or not the current sampling cycle has passed the point (A) where the distance L to the target position T is La, and if so, the process proceeds to step S61. If so, the process proceeds to step S65.

In the present embodiment, the sampling period in which the distance L is smaller than La in the previous sampling period and the distance L is greater than or equal to La in the current sampling period is determined as the moment of passing.
In step S61, the driver's intention to decelerate is determined from the vehicle speed V and the acceleration α.
In the present embodiment, the driver's intention to decelerate is determined as follows.
First, when the vehicle speed V of the host vehicle is equal to or higher than the limit vehicle speed Vlim (L) at the moment of passing through the point (A), the driver is not aware of the intersection and does not intend to decelerate or cannot decelerate. Judge that it is enough. Then, 1 is set to the deceleration intention determination flag FL.

On the other hand, when the vehicle speed V of the host vehicle is smaller than the limit vehicle speed Vlim (L), the required acceleration αth (unit: m / s ² ) is calculated from the current vehicle speed V and the first set vehicle speed Vs1 as shown in Expression (7). Ask.
αth = (Vs1 ² −V ² ) / (2L) (7)
This αth is an acceleration that becomes the speed of the first set vehicle speed Vs1 at the target position T when the vehicle is decelerated or accelerated while maintaining the acceleration of the required acceleration αth from the current vehicle speed V.
Further, the current acceleration α (unit: m / s ² ) is obtained by time differentiation of the current vehicle speed V.
Then, the current acceleration α is compared with the required acceleration αth. If α> αth, it is determined that there is no or insufficient intention to decelerate, and 1 is set in the deceleration intention determination flag FL. If α ≦ αth, it is assumed that there is an intention to decelerate, and the deceleration intention determination flag FL is set to 0.

The determination of the intention of deceleration, that is, the condition for setting the deceleration intention determination flag FL to 1 is also performed when the vehicle speed V of the host vehicle becomes higher than the second transition vehicle speed Vlim2 (L).
Since the processes in steps S65, S70, S85, and S95 are the same as those in the second embodiment, a description thereof will be omitted.
In step S98, when it is determined that the assist brake pressure control amount P is greater than 0, a message “Decelerate” is displayed on the screen of the navigation system 3, and at the same time, the driver “slows down”. Please warn me ". This message and warning are canceled when it is detected that the brake pressure control amount P has become 0, for example, when the driver depresses the brake and decelerates.

In step S98, if it is detected that the current vehicle speed V is greater than the vehicle speed of the warning vehicle speed Vara (L) (km / h), a message “Decelerate” is displayed on the screen of the navigation system 3. At the same time as displaying, it is better to warn the driver with a voice "Please decelerate".
In the present embodiment, the warning vehicle speed Vara (L) is reduced by a predetermined subtraction vehicle speed ΔVara, for example, 2 km / h, from the limit vehicle speed Vlim (L) that sets the distance L to the target position T as a variable, as shown in the following equation. Set as the vehicle speed.
Vara (L) = Vlim (L) −ΔVara

Note that the alarm vehicle speed Vara (L) is preferably increased by increasing the vehicle speed ΔVara subtracted from the limit vehicle speed Vlim (L), for example, as the current vehicle speed increases. This is because when the vehicle speed to be reduced is constant, the larger the absolute value of the vehicle speed, the shorter the time from when the warning vehicle speed Vara (L) is exceeded and when the warning or warning is issued until the brake control is intervened beyond the vehicle speed limit. This is because it has the effect of mitigating the difficulty of the driver taking measures such as stepping on the brake. Alternatively, the vehicle speed ΔVara may be set to be larger as the distance L is smaller, that is, as the distance from the target position T is larger.
Since the processes in steps S100 and S110 are the same as those in the first embodiment, a description thereof will be omitted.

(Operation / Action)
An example of the control according to this embodiment will be described with reference to FIG.
For example, in the case of a solid line B5 that is driving indiscriminately and has entered the intersection without noticing the intersection, the vehicle speed is limited after passing the point (E) exceeding the second transition vehicle speed Vlim2 (L), Control is performed so that the second set vehicle speed Vs2 is reached at the target position T.
In the case of the solid line B5, when the vehicle speed V of the host vehicle at the point (A) where the limit vehicle speed Vlim and the second transition vehicle speed Vlim2 cross each other is decelerated at a constant required acceleration αth, a one-dot broken line Vα3 is obtained. Accordingly, since the slope of the solid line B5 exceeds the slope of the one-dot broken line Vα3 at the point (A), it is determined that there is no intention of deceleration, and the deceleration control is performed so as to be equal to or lower than the second transition vehicle speed Vlim2 (L). The required acceleration αth is obtained according to the equation (7) described in step S58 of the third embodiment.

At this time, if the brake pressure control amount P is greater than 0, or if the vehicle speed V of the host vehicle is greater than the warning vehicle speed Vara (L), “Decelerate” on the screen of the navigation system 3. Is displayed and at the same time, the driver is warned by voice "Please decelerate".
In addition, it is determined that there is an intention to decelerate at the point (A), and then it is determined that there is an intention to decelerate when the second transition vehicle speed Vlim2 (L) is exceeded. In the case of a solid line B6 where it is determined that the vehicle cannot be decelerated so as to travel at a constant speed at the set vehicle speed Vs1, the deceleration control is performed so that the vehicle speed becomes equal to or lower than the limit vehicle speed Vlim after passing through the point (G).
In the case of the solid line B6, when the vehicle speed at the point (A) where the limit vehicle speed Vlim and the second transition vehicle speed Vlim2 intersect is decelerated at a constant required acceleration αth, a one-dot broken line Vα5 is obtained. At this time, since the slope of the solid line B6 is lower than the slope of the dashed line Vα5 at the point (A), it is determined that there is an intention of deceleration.

Similarly, when the vehicle speed at the point (F) exceeding the second transition vehicle speed Vlim2 (L) is decelerated at a constant required acceleration αth, a one-dot broken line Vα4 is obtained. Even at the point (F), since the slope of the solid line B6 is lower than the slope of the dashed line Vα4, it is finally determined that the driver intends to decelerate. After that, deceleration control is performed so as not to exceed the limit vehicle speed Vlim that decelerates to the first set vehicle speed Vs1.
At this time, if the brake pressure control amount P is greater than 0, or if the vehicle speed V is greater than the warning vehicle speed Vara (L), the message “Decelerate” is displayed on the screen of the navigation system 3. At the same time, a warning is given to the driver saying “Decelerate”.
Here, step S98 constitutes a notification means and a preliminary notification means.

(Effect of this embodiment)
(1) When the vehicle speed limiting unit limits the vehicle speed of the host vehicle, the notification unit notifies the driver that the vehicle speed is limited.
By notifying the driver of warnings, warnings, etc. when assist deceleration control intervenes, the driver can easily understand why deceleration control is intervening. As a result, it is possible to prompt a response for safety such as stepping on the brake by itself, and it can be expected to secure more safety.
(2) When the preliminary notification means determines that the vehicle speed of the host vehicle is equal to or higher than the warning vehicle speed, the preliminary notification means notifies the driver of a warning.
This makes it possible for the driver to notice that it is close to the intersection.

It is a schematic diagram which shows the vehicle structure which concerns on embodiment based on this invention. It is a schematic diagram which shows the vehicle structure which concerns on embodiment based on this invention. It is a figure which shows the structure of a navigation system. It is a figure which shows the structure of a controller. It is a figure explaining the process of the controller main body which concerns on 1st Embodiment based on this invention. It is a figure explaining the target position T etc. FIG. It is a figure explaining the limit vehicle speed etc. which concern on 1st Embodiment based on this invention. It is a figure which shows the relationship between a brake stroke and braking force. It is a figure explaining the process of the controller main body which concerns on 2nd Embodiment based on this invention. It is a figure explaining the limiting vehicle speed etc. which concern on 2nd Embodiment based on this invention. It is a figure explaining another example which concerns on 2nd Embodiment based on this invention. It is a figure explaining the process of the controller main body which concerns on 3rd Embodiment based on this invention. It is a figure explaining the limit vehicle speed etc. which concern on 3rd Embodiment based on this invention. It is a figure explaining the process of the controller main body which concerns on 4th Embodiment based on this invention. It is a figure explaining the limiting vehicle speed etc. which concern on 4th Embodiment based on this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Vehicle 1a Front bumper 3 Navigation system 4 Controller 4A Drive controller 4B Braking controller 4C Controller main body 10 Navigation system FL Deceleration intention determination flag P Assist brake pressure control amount T Target position V Own vehicle speed V Vehicle speed Vara Warning vehicle speed Vlim Limit vehicle speed Vlim2 Second Transition vehicle speed Vs1 First set vehicle speed Vs2 Second set vehicle speed X Intersection α Acceleration αth Required acceleration

Claims (13)

Target value setting means for setting a target position when entering the intersection;
Distance detecting means for detecting the distance of the host vehicle with respect to the target position;
Limit vehicle speed setting means for setting a limit vehicle speed based on the distance of the host vehicle with respect to the target position;
Vehicle speed detection means for detecting the vehicle speed of the host vehicle;
Deceleration intention estimation means for determining the presence or absence of a deceleration intention when entering the intersection on the near side of the target position based on the distance of the host vehicle to the target position, the vehicle speed of the host vehicle, and the limit vehicle speed;
When the deceleration intention estimation means determines that there is a deceleration intention, the first set vehicle speed is selected as the vehicle speed at the target position, and when the deceleration intention estimation means determines that there is no deceleration intention, Vehicle speed selection means for selecting a second set vehicle speed lower than the first set vehicle speed as the vehicle speed at the target position;
When it is determined that the vehicle speed of the host vehicle is higher than the set vehicle speed selected by the vehicle speed selection unit, the vehicle speed of the host vehicle is selected by the vehicle speed selection unit at the target position or a selected position that is offset by a predetermined value back and forth from the target position. A driving assistance device comprising: vehicle speed limiting means for performing deceleration control so as to be equal to or lower than a set vehicle speed.   The decelerating intention estimation means determines that there is an intention to decelerate when the vehicle speed of the host vehicle is less than the limit vehicle speed, and determines that there is no intention of deceleration when the vehicle speed of the host vehicle is equal to or higher than the limit vehicle speed. The driving support apparatus according to claim 1, further comprising a determination unit. An acceleration detecting means for measuring the acceleration of the host vehicle;
The decelerating intention estimating means includes second determining means for determining a driver's intention to decelerate based on the distance detected by the distance detecting means, the speed of the own vehicle, and the acceleration of the own vehicle. The driving support apparatus according to claim 1 or 2.   The driving assistance apparatus according to any one of claims 1 to 3, wherein the limit vehicle speed setting means sets the limit vehicle speed to be lower as the distance to the target position is smaller. The vehicle speed is equal to or higher than the limit vehicle speed, and the upper limit vehicle speed is lower as the distance to the target position is smaller.
The said vehicle speed restriction | limiting means restrict | limits the upper limit of the vehicle speed of the own vehicle to the said upper limit vehicle speed or less based on the distance to the said target position, It described in any one of Claims 1-4 characterized by the above-mentioned. Driving assistance device. Set a first transition vehicle speed that becomes lower as approaching the selected position and becomes the first set vehicle speed at the selected position;
The vehicle speed limiting means restricts the upper limit of the vehicle speed of the host vehicle to the first transition vehicle speed based on the distance detected by the distance detection means when the vehicle speed selection means selects the first set vehicle speed. The driving support device according to any one of claims 1 to 5, wherein the driving support device is characterized.   The driving assistance device according to claim 6, wherein the first transition vehicle speed is a first set vehicle speed before the selected position. Set a second transition vehicle speed that becomes lower as approaching the selected position and becomes the second set vehicle speed at the selected position;
The vehicle speed limiting means limits the upper limit of the vehicle speed of the host vehicle to the second transition vehicle speed based on the distance detected by the distance detection means when the vehicle speed selection means selects the second set vehicle speed. The driving support apparatus according to any one of claims 1 to 7.   The driving assistance apparatus according to claim 8, wherein the second transition vehicle speed is a second set vehicle speed before the selected position.   10. The vehicle according to any one of claims 1 to 9, further comprising notification means for notifying a driver that the vehicle speed is restricted when the vehicle speed restriction means restricts the vehicle speed of the host vehicle. Driving assistance device. A vehicle speed lower than the vehicle speed at which the vehicle speed limiting means limits the vehicle speed of the host vehicle is set as an alarm vehicle speed,
The driving support device according to any one of claims 1 to 10, further comprising preliminary notification means for notifying a driver of a warning when the vehicle speed of the host vehicle is determined to be equal to or higher than an alarm vehicle speed.   The driving support device according to any one of claims 1 to 11, wherein the vehicle speed restriction by the vehicle speed restriction means is performed when the own lane is a non-priority road. Set the speed limit based on the distance to the target position when entering the intersection,
Based on the limit vehicle speed, the distance to the target position, and the vehicle speed of the host vehicle, it is determined whether or not there is an intention to decelerate when entering the intersection, and if it is determined that there is an intention to decelerate, the vehicle speed at the target position is When the first set vehicle speed is selected and it is determined that there is no intention to decelerate, the second set vehicle speed lower than the first set vehicle speed is selected as the vehicle speed at the target position, and the vehicle enters the intersection. A driving support method, wherein the vehicle speed of the host vehicle is limited to be equal to or lower than a selected set vehicle speed.

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