JP2004355266A - Notification device for vehicle - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To previously determine whether it is a proper traveling condition or not during passage through a curved road ahead of a vehicle and to inform it to a driver if necessary. <P>SOLUTION: If there is a curve ahead of a vehicle, a curve entering vehicle speed V* is computed on the basis of a curve radius at a curve entrance point of the curve, a distance Lrs from the vehicle to the curve entrance point is divided by a speed deviation ΔV between the curve entering vehicle speed V* and a traveling speed Vc of the vehicle to find a collision time TTC to be used as a passage margin (step S4). When the passage margin is lower than a threshold value and it is determined that the present traveling condition is not suitable for passing through the curve ahead of the vehicle (step S7), a correction amount Fc is computed according to the collision time TTC and a speed deviation ΔV. When a driving power working on the vehicle is reduced by the correction amount Fc and a braking force is applied as a result, the driver is notified that it is not in a proper traveling condition (step S8, S9). <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention performs deceleration control depending on whether the traveling state of the own vehicle is a traveling state suitable for a road shape such as a curved road to be passed from now on, and the traveling state is inappropriate due to a speed change of the own vehicle. The present invention relates to a vehicle notification device for notifying whether or not the notification is made.
[0002]
[Prior art]
Conventionally, there has been proposed a speed control device that detects a forward object in front of a host vehicle, regards the detected forward object as a preceding vehicle, and performs travel control so that an inter-vehicle distance to the forward object is constant. (For example, see Patent Document 1).
[0003]
[Patent Document 1]
JP-A-9-263159
[0004]
[Problems to be solved by the invention]
However, as described in Patent Literature 1, when speed control is performed so that the inter-vehicle distance between the host vehicle and a front object is constant, for example, when a curved road exists in front of the host vehicle In some cases, a guardrail or a reflector (a delineator) provided on the curved road may be erroneously detected as a forward stop object. For this reason, a braking force is generated for the erroneously detected front stop object such as the guardrail, and the stop object is actually a guardrail or the like and is not an obstacle even though it is not an obstacle. As a result, there is a problem that the automatic braking is operated and the driver may be troubled or feel uncomfortable. However, even when the vehicle is erroneously detected as a stationary object such as a guardrail on a curved road, if the traveling state of the own vehicle is not appropriate when entering the curved road, the driver is notified that the traveling state is inappropriate. That is useful.
[0005]
Accordingly, the present invention has been made in view of the above-mentioned conventional unsolved problem, and gives annoyance to a driver due to erroneous detection of a guardrail or the like as a stationary object on a curved road ahead of the host vehicle. It is an object of the present invention to provide a vehicle notification device capable of effectively notifying a driver of a traveling state that is not appropriate for traveling on a curved road while avoiding such a situation.
[0006]
[Means for Solving the Problems]
In order to achieve the above object, a vehicle alerting device according to the present invention provides a vehicle with a passing margin based on a road shape detected by a road shape detecting means and a traveling speed detected by a traveling speed detecting means. The estimating means estimates the pass margin of the own vehicle when passing through the portion corresponding to the road shape, and based on the pass margin, the travel of the own vehicle when passing through the portion corresponding to the road shape. The appropriateness of the state is determined.
[0007]
Then, according to the determination result, at least one of the driving torque and the braking torque is changed by the appropriate notification means to apply a braking force to the own vehicle, thereby notifying whether or not the traveling state is appropriate. Done.
Therefore, the driver can recognize in advance whether or not the vehicle is in an appropriate running state when passing through a location corresponding to the road shape ahead of the host vehicle, depending on whether or not the braking force is applied. It becomes possible.
[0008]
【The invention's effect】
The vehicle notification device according to the present invention is based on the road shape detected by the road shape detection means and the traveling speed detected by the traveling speed detection means, and is equivalent to the road shape by the passage margin estimation means. Estimate the pass margin of the own vehicle when passing through the place where the vehicle travels, and determine the appropriateness of the traveling state of the own vehicle when passing the place corresponding to the road shape based on the pass allowance, and determine the determination result. The appropriate notifying means changes at least one of the driving torque and the braking torque to generate the braking force, so that the driver can correspond to the road shape ahead of the host vehicle depending on whether the braking force is generated. When passing through a place where the vehicle is traveling, it is possible to recognize in advance whether or not the vehicle is in a proper traveling state. Therefore, when the traveling state is not appropriate, by taking measures in advance so as to be an appropriate traveling state, it is possible to pass in a proper traveling state when actually passing through a portion corresponding to the road shape. And safety can be improved.
[0009]
BEST MODE FOR CARRYING OUT THE INVENTION
Hereinafter, embodiments of the present invention will be described with reference to the drawings.
First, a first embodiment will be described.
FIG. 1 is a schematic configuration diagram showing a traveling control system in which the vehicle notification device of the present invention is incorporated.
The traveling control system includes wheel speed sensors 1FL to 1RR for detecting the wheel speed of each wheel, a brake pedal 3, an accelerator pedal 4, a braking force control device 20, a driving force control device 10, a navigation device 40, a notification control controller 5, and It is configured to include the engine 6.
[0010]
The driving force control device 10 controls the engine 6 to generate a driving force according to the operation state of the accelerator pedal 4 and changes the generated driving force according to a command from the notification control controller 5. It is configured as follows.
FIG. 2 is a block diagram showing a configuration of the driving force control device 10. As shown in FIG. The driving force control device 10 includes a driver required driving force calculation unit 11, an adder 12, and an engine controller 13.
[0011]
The driver required driving force calculation unit 11 calculates a driving force required by the driver (hereinafter, referred to as a driver required driving force) in accordance with the depression amount of the accelerator pedal 4 (hereinafter, referred to as an accelerator pedal depression amount). For example, the driver required driving force calculation unit 11 uses a characteristic map (hereinafter, referred to as a driver required driving force calculation map) that defines the relationship between the accelerator pedal depression amount and the driver required driving force as shown in FIG. And the driver's required driving force corresponding to the accelerator pedal depression amount. Then, the driver required driving force calculation unit 11 outputs the obtained driver required driving force to the engine controller 13 via the adder 12. Note that the driver required driving force calculation map is held by the driver required driving force calculating unit 11.
[0012]
The engine controller 13 calculates a control command value to the engine 6 using the driver required driving force as a target driving force. The engine 6 is driven based on the control command value. Further, the driving force correction amount is input to the adder 12 of the driving force control device 10, and when the driving force correction amount is input to the driving force control device 10, the engine controller 13 Then, the target driving force including the corrected driver request driving force to which the driving force correction amount is added by the adder 12 is input.
[0013]
As described above, the driving force control device 10 calculates the driver request driving force according to the accelerator pedal depression amount by the driver request driving force calculation unit 11, and when the driving force correction amount is separately input, The target driving force obtained by adding the driving force correction amount by the adder 12 is obtained, and the engine controller 13 calculates a control command value corresponding to the target driving force.
[0014]
The braking force control device 20 controls the brake fluid pressure so as to generate a braking force according to the operation state of the brake pedal 3 and changes the generated braking force according to a command from the notification controller 5. It is configured as follows.
FIG. 4 is a block diagram showing a configuration of the braking force control device 20. The braking force control device 20 includes a driver required braking force calculation unit 21, an adder 22, and a brake fluid pressure controller 23.
[0015]
The driver required braking force calculation unit 21 calculates a braking force required by the driver (hereinafter, referred to as a driver required braking force) according to the amount of depression of the brake pedal 3 (hereinafter, referred to as the amount of depression of the brake pedal). For example, as shown in FIG. 5, the driver request braking force calculation unit 21 uses a characteristic map (hereinafter, referred to as a driver request braking force calculation map) that defines the relationship between the amount of depression of the brake pedal and the driver request braking force. By using this, the driver's required braking force corresponding to the brake pedal depression amount is obtained. Then, the driver required braking force calculation unit 21 outputs the obtained driver required braking force to the brake fluid pressure controller 23 via the adder 22. Note that the driver request braking force calculation map is held by the driver request braking force calculation unit 21.
[0016]
The brake fluid pressure controller 23 calculates a brake fluid pressure command value using the driver's requested braking force as a target braking force. Further, the braking force control unit 20 receives the braking force correction amount input to the adder 22, and when the braking force correction amount is input, the braking fluid pressure controller 23 transmits the braking force correction amount to the adder 22. A target braking force including the driver's requested braking force after the addition of the braking force correction amount is input.
[0017]
As described above, the braking force control device 20 calculates the driver's requested braking force in accordance with the brake pedal depression amount in the driver's requested braking force calculation unit 21. On the other hand, when the braking force correction amount is separately input, Obtains the target driving force obtained by adding the braking force correction amount by the adder 22, and calculates the brake fluid pressure command value corresponding to the target braking force by the brake fluid pressure controller 23.
[0018]
The navigation device 40 includes, for example, a latitude and longitude calculation unit 41, a map matching processing unit 42, a map unit 43, and a screen display unit 44, as shown in FIG.
The latitude and longitude calculation unit 41 calculates the latitude and longitude of the own vehicle based on the satellite position and time information sent from the GPS antenna. The map unit 43 stores map information as a digital map. Here, the digital map in the map unit is linked to a database representing road types. The map matching processing unit 42 performs map matching based on the latitude and longitude information obtained by the latitude and longitude calculation unit 41 and the map information of the map unit 43, and specifies the position of the vehicle on the map. The screen display unit 44 recognizes the road shape ahead of the host vehicle based on the host vehicle position on the map specified by the map matching processing unit 42. Then, when there is a curved road ahead of the host vehicle, a curve radius of a curve entrance existing ahead and a distance to the curve entrance are detected. The information and the road type information called from the database for the road determined by the map matching processing unit 42 to be traveling are transmitted to the notification controller 5.
[0019]
The notification control controller 5 includes various types of information such as wheel speed information of the wheel speed sensors 1FL to 1RR, detection results of the obstacle detection processing device 2, operation state information of the accelerator pedal 4, and road type information from the navigation device 40. Information is input, and a command signal for driving the driving force control device 10 and the braking force control device 20 is calculated based on the information.
FIG. 7 is a block diagram showing the logic of the arithmetic processing performed by the notification controller 5.
[0020]
The notification controller 5 includes a traveling speed estimating unit 101 for estimating the traveling speed of the own vehicle based on detection signals from the wheel speed sensors 1FL to 1RR, the own vehicle traveling speed estimated by the traveling speed estimating unit 101, and navigation. Based on the navigation information from the device 40, when the own vehicle passes through the forward curve, the pass margin calculating unit 102 that calculates a pass margin, which indicates whether the vehicle is traveling at an appropriate traveling speed, the pass margin A repulsive force calculating unit 103 that calculates a repulsive force according to the passing margin calculated by the degree calculating unit 102, a driver request torque calculating unit 104 that calculates a driving torque required by the driver based on the depression amount of the accelerator pedal 4, , Based on the repulsion force calculated by the repulsion force calculation unit 103 and the driver request torque calculated by the driver request torque calculation unit 104. And the target torque to be generated by the engine 6 and the braking torque to be generated by the brake fluid pressure controller 23 are calculated based on the calculated target torque. And a target torque calculating unit 105 for calculating the target torque.
[0021]
Next, a description will be given of the arithmetic processing of FIG. 8 executed by the notification controller 5 in order to achieve the logic of FIG. This arithmetic processing is performed, for example, for 10 msec. It is executed every predetermined sampling time ΔT set to the extent. In this arithmetic processing, particularly, no step for communication is provided, but necessary information is exchanged with another controller or a storage device at any time, and information obtained by the arithmetic processing is exchanged with another controller at any time. Alternatively, it is exchanged with a storage device.
[0022]
In this calculation processing, first, in step S1, the current position of the own vehicle, the road shape in front of the own vehicle, the curve entrance radius Rs of the curve entrance point Cs, and the distance from the own vehicle to this curve entrance point Cs are determined from the navigation device 40. The predetermined navigation information such as the distance Lrs is read. Note that the curve entrance point Cs represents a point where the road curvature changes, as shown in FIG.
[0023]
Next, the process proceeds to step S2 to determine whether there is a curved road ahead of the vehicle based on the navigation information. When it is determined that there is no curved road, the process proceeds to step S3, where Fc = 0 is set as the repulsive force Fc, and this is set as a correction amount. Then, the process ends.
On the other hand, when it is determined that there is a curved road, the process proceeds to step S4, and the pass margin is calculated.
[0024]
The calculation of the passage allowance is performed according to the procedure shown in FIG.
First, in step S12, the target lateral acceleration Yg at the time of entering the notified curved road is obtained. ^* Is defined. This target lateral acceleration Yg ^* Is set to a value that allows the vehicle to run stably when traveling on the curved road, for example, to about 0.4 G. Note that this target lateral acceleration Yg ^* However, as the value increases, the curve approach speed increases, and the direction in which the automatic braking control is difficult to start is increased.
[0025]
Next, the process proceeds to step S14, and based on the navigation information obtained from the navigation device 40, the curve entry radius Rs of the curve entry point Cs and the distance Lrs from the host vehicle to the curve entry point Cs are specified. The running speed of the host vehicle is calculated based on the detection signals of the wheel speed sensors 1FL to 1RR.
Next, the process proceeds to step S16, in which the vehicle enters the target curve approaching vehicle speed V with respect to the curve entry point Cs. ^* Is calculated according to the following equation (1).
[0026]
V ^* = (Yg ^* × Rs) ^1/2 ...... (1)
Next, the process proceeds to step S18, in which a margin for passage with respect to the curve entrance radius Rs is calculated. Here, the collision time TTC with respect to the curve entrance point Cs is calculated as the passage allowance.
Specifically, the traveling speed Vc of the own vehicle is the vehicle speed V entering the curve. ^* Greater than (Vc> V ^* ), The collision time TTC is calculated from the following equation (2) as a pass margin.
[0027]
TTC = Lrs / (Vc−V ^* …… (2)
On the other hand, when the traveling speed Vc of the own vehicle is equal to ^* The following (where Vc ≦ V ^*) In the case of, the collision time TTC is set to a large positive value, that is, a value TTCmax larger than a later-described threshold TTCth of the passage margin, as the passage margin.
Then, when the margin TTC is set in this way, the process returns to FIG. 8 and then proceeds to step S5.
[0028]
In this step S5, a control intervention threshold value TTCth and a repulsive force gain K are defined. The control intervention threshold value TTCth is set, for example, based on experimental data of a normal driving operation of the driver so as to be slower than the driver operation (brake operation). The control intervention threshold value TTCth is not limited to a fixed value, and may be changed according to the vehicle speed. For example, the control intervention threshold value TTCth may be set to a value that increases as the vehicle speed increases.
[0029]
On the other hand, the repulsion force gain K is a predetermined value set in advance. Note that the repulsive force gain K may be set based on, for example, the magnitude of the deceleration to be notified just before the curve.
Subsequently, the process proceeds to step S6, in which the curve approaching vehicle speed V calculated in step S16 from the running speed Vc of the own vehicle is used. ^* Is subtracted to calculate the vehicle speed deviation ΔV.
[0030]
Next, the process proceeds to step S7, where a magnitude relationship between the collision time TTC as the pass margin set in step S18 and the control intervention threshold TTCth set in step S5 is determined, and when TTC <TTCth, Then, the process proceeds to step S8, where the negative value of the repulsive force F is calculated based on the following equation (3), and this is used as the correction amount.
F = K (TTC−TTCth) × ΔV (3)
On the other hand, if the passage allowance TTC is equal to or greater than the control intervention threshold TTCth in step S7, the process proceeds to step S3, where the repulsive force F is set to F = 0, and this is set as a correction amount.
[0031]
The repulsive force F is calculated based on the following assumption.
That is, as shown in FIG. 11A, a virtual elastic body (hereinafter, referred to as a virtual elastic body) 500 exists in front of the vehicle 300, and a virtual stationary object (hereinafter, referred to as a virtual stop object) is provided at the curve entrance point Cs. Hereinafter, a virtual object is assumed.) A model in which 400 exists is assumed. That is, in this model, when the distance between the host vehicle 300 and the virtual object 400 becomes equal to or less than a certain distance, the virtual elastic body 500 comes into contact with the virtual object 400 and is compressed. Of the vehicle 300 as a pseudo running resistance.
[0032]
The length L (TTC) of the virtual elastic body in this model is given by the following equation (4) in association with the control intervention threshold TTCth according to the speed deviation ΔV.
L (TTC) = TTCth × ΔV (4)
Assuming that the elastic coefficient of the virtual elastic body 500 having the length L (TTC) is the repulsion force gain K, as shown in FIG. When the virtual object 400 is located within the range of L (TTC), the virtual elastic body 500 is assumed to change according to the distance between the host vehicle 300 and the virtual object 400, that is, the amount corresponding to the elastic displacement. Is given as the above equation (3).
[0033]
That is, the distance between the vehicle 300 and the virtual object 400 corresponds to the distance Lrs to the curve entrance point Cs, and as shown in the above equation (2), the collision time TTC is the distance Lrs to the curve entrance point Cs. "Vc-V ^* ", That is, a value obtained by dividing by the velocity deviation ΔV. The length L (TTC) of the virtual elastic body 500 is given by the above equation (4). Therefore, the above equation (3) is derived. .
[0034]
That is, according to this model, when the distance between the vehicle 300 and the virtual object 400 is shorter than the reference length, that is, the length L (TTC) of the virtual elastic body 500, the model has the elastic coefficient K. The resilient force F is generated by the virtual elastic body 500. Here, the elastic coefficient K is the above-described repulsive force gain K, and is a control parameter adjusted so that an appropriate warning effect can be obtained by control.
[0035]
From the above relationship, when the distance from the vehicle to the curve entry point Cs is long and TTC <TTCth is not satisfied, the resilient force F is not generated because the virtual elastic body 500 is not compressed. Therefore, the repulsive force F becomes 0 (step S3). On the other hand, the distance from the host vehicle to the curve entry point Cs is short and TTC <TTC ^* In this case, since the virtual elastic body 500 is compressed, the repulsive force F of the virtual elastic body 500 is calculated from the equation (3) according to the elastic displacement of the virtual elastic body 500. Then, it is necessary to correct the braking / driving force set in accordance with the operation of the accelerator pedal or the brake pedal by an amount corresponding to the repulsive force F calculated in this way, and this is set as the correction amount Fc.
[0036]
After calculating the correction amount Fc in this way, the process proceeds to step S9, and calculates a correction amount for correcting the outputs of the driving force control device 10 and the braking force control device 20 according to the correction amount Fc. Correction amount calculation processing to be performed.
Specifically, as shown in FIG. 12, first, at step S41, the notification controller 5 reads the accelerator pedal depression amount, and then proceeds to step S42, where the driver performs the operation based on the accelerator pedal depression amount. The required driving force Fd, which is the required driving force, is estimated. Specifically, the notification controller 5 uses the same map as the driver required driving force calculation map shown in FIG. 3 that is used by the driving force control device 10 to calculate the driver required driving force. The driver's requested driving force Fd according to the pedal depression amount is estimated.
[0037]
Next, the process proceeds to step S43, in which the estimated driver required driving force Fd is compared with the correction amount Fc (= repulsion force F) calculated in the process of step S3 or step S8, and the driver required driving force Fd is corrected. If it is above (Fd ≧ Fc), the process proceeds to step S44, and if the driver required driving force Fd is smaller than the correction amount Fc (Fd <Fc), the process proceeds to step S46.
[0038]
In step S44, the correction amount Fc is output to the driving force control device 10 as a driving force correction amount, and the process proceeds to step S45 to output zero to the braking force control device 20 as a braking force correction amount.
On the other hand, in step S46, a negative value (-Fd) of the driver required driving force Fd is output to the driving force control device 10 as the driving force correction amount, and the process proceeds to step S47 to change the driver required driving force from the correction amount Fc. A value (Fc-Fd) obtained by subtracting the force Fd is output to the braking force control device 20 as a braking force correction amount.
[0039]
As a result, the driving force control device 10 performs a process as a target driving force with a value obtained by adding the driving force correction amount from the notification control controller 5 to the driver request driving force. Processing is performed with a value obtained by adding the braking force correction amount from 5 to the driver requested braking force as the target braking force.
With the above configuration, the traveling control system controls the engine 6 so that the driving force control device 10 generates a driving force corresponding to the operation amount of the accelerator pedal 4, and the braking force control device 20 controls the brake pedal 3. The braking force is controlled so as to generate a braking force in accordance with the operation amount of. At this time, the travel control system corrects each control amount according to the operation state of the accelerator pedal 4 or the brake pedal 3 depending on whether there is a curved road ahead of the host vehicle.
[0040]
Next, the operation of the first embodiment will be described.
Now, when the vehicle is traveling on a road that does not have a curved road ahead of the vehicle, the presence of the curved road is not detected based on the navigation information read from the navigation device 40. After step S2, the process proceeds to step S3, where the repulsive force F is set to F = 0. Accordingly, since the repulsion force F is zero, that is, the correction amount Fc is zero, both the driving force correction amount and the braking force correction amount are set to zero (steps S44 and S45 in FIG. 12).
Therefore, since both the driving force correction amount and the braking force correction amount are zero, the driving force control device 10 and the braking force control device 20 generate the braking force and the driving force according to the depression amounts of the brake pedal 3 and the accelerator pedal 4. The braking operation and the driving force intended by the driver are generated according to the operation amounts of the brake pedal 3 and the accelerator pedal 4.
[0041]
From this state, when the navigation device 40 notifies that there is a curved road ahead of the traveling road of the own vehicle, the process proceeds from step S2 to step S4, and reaches the curve entrance point Cs shown in FIG. 10 based on the navigation information. , A curve entrance radius Rs is specified, and the traveling speed Vc of the own vehicle is specified based on detection signals of the wheel speed sensors 1FL to 1RR (step S14 in FIG. 9). Vehicle speed V ^* Is calculated (step S16 in FIG. 9).
[0042]
At this time, the host vehicle is traveling at a relatively low vehicle speed, and ^* If the traveling speed Vc is lower than Tcmax, TTCmax is set as the margin of passage (collision time) TTC (step S18).
Therefore, the passage allowance TTC exceeds the control intervention threshold value TTCth (step S7), the process proceeds to step S3, and the repulsive force F, that is, the correction amount Fc is set to zero (step S3).
[0043]
Therefore, since the braking force correction amount and the driving force correction amount calculated based on the correction amount Fc become zero, the host vehicle travels at a relatively low vehicle speed, and travels at an appropriate speed when entering a curved road. When it is determined that the vehicle is running, the braking force and the driving force are not corrected, and the vehicle travels in a traveling state according to the operation of the brake pedal 3 and the accelerator pedal 4 intended by the driver.
[0044]
On the other hand, when the vehicle is traveling at a relatively high vehicle speed, ^* If the traveling speed Vc is higher than the ^* The travel allowance TTC is calculated based on the travel speed Vc and the distance Lrs from the vehicle to the curve entrance point Cs. At this time, the shorter the distance Lrs to the curve entrance point Cs, the more the vehicle speed Vc Curve approach speed V ^* The greater the difference from the above, the smaller the allowance TTC is set to a smaller value.
[0045]
For this reason, when the allowance TTC falls below the threshold TTCth, the process proceeds from step S7 to step S8, where the allowance TTC and the threshold TTCth, the traveling speed Vc of the host vehicle, and entry into a curved road. Vehicle speed V ^* , A negative value repulsive force F is calculated, and this is the correction amount Fc (step S8).
[0046]
At this time, when the driver depresses the accelerator pedal 4 for the purpose of acceleration, and when the driver's required driving force Fd according to the depressed amount exceeds the correction amount Fc, the process proceeds from step S43 to step S44 in FIG. A negative value -Fc is output as the force correction amount, and zero is output as the braking force correction amount. Therefore, the driving force control device 10 operates so as to generate a driving force of a magnitude obtained by subtracting the driving force correction amount “−Fc” from the driving force corresponding to the depression amount of the accelerator pedal 4. When the vehicle is depressed, the own vehicle exhibits a slow acceleration behavior.
[0047]
Therefore, although the driver depresses the accelerator pedal 4 for the purpose of acceleration, an expected driving force corresponding to the depression amount, that is, a feeling of acceleration cannot be obtained. Therefore, the driver can recognize that the vehicle is traveling at a speed too high for stable traveling when the vehicle enters a curved road due to the blunt acceleration behavior, It is possible to take measures for realizing stable traveling in advance on a curved road entry, such as performing deceleration traveling before entering a curved road. Therefore, when the vehicle enters a curved road, the vehicle enters the vehicle in a sufficiently decelerated state, so that the vehicle can travel stably on the curved road.
[0048]
On the other hand, at this time, if the driver's required driving force Fd is smaller than the correction amount Fc, such as when the driver does not depress the accelerator pedal 4 so much, or when the accelerator pedal 4 is not depressed, the process proceeds from step S43 to step S46. Then, -Fd is set as the driving force correction amount, and Fc-Fd is output as the braking force correction amount.
[0049]
Therefore, the driving force control device 10 generates a driving force having a value obtained by subtracting the driving force correction amount −Fd from the driver request driving force Fd corresponding to the depression amount of the accelerator pedal 4, that is, the driver request driving force. In addition to operating so that the force Fd is not generated, the braking force control device 20 operates to generate a braking force having a magnitude obtained by adding the braking force correction amount Fc-Fd to the driver's required braking force.
[0050]
As a result, the actual driving force becomes substantially zero with respect to the driving force requested by the driver, and the actual braking force becomes larger than the braking force requested by the driver by an amount equivalent to the braking force correction amount Fc-Fd.
Therefore, when the driver required driving force Fd is less than the correction amount Fc, the target repulsive force cannot be obtained only by the control of the driving force control device 10. The repulsive force F is obtained by outputting the negative value -Fd of Fd as the driving force correction value, and outputting Fc-Fd corresponding to the shortage to the braking force control device 20 as the braking force correction amount. Like that. That is, the driving force control device 10 and the braking force correction device 20 cooperate to obtain a desired repulsion force F as the whole system, and the repulsion force is applied to the vehicle as running resistance.
[0051]
Therefore, when the depression amount of the accelerator pedal 4 does not reach the predetermined amount Fc, the braking force is increased by the shortage Fc-Fd with respect to the braking force requested by the driver, and the vehicle is decelerated by the braking force. Behaves. That is, although the driver cannot depress the accelerator pedal 4 and cannot obtain a sufficient driving force and conversely applies the braking force, or the driver does not operate the brake pedal 3, The fact that a braking force acts on the vehicle means that there is a curved road ahead of the host vehicle, and that the current running state is a running state that is too fast for stable running on this curved road. At this point, it is possible to take measures such as deceleration.
[0052]
Therefore, by using such a deceleration behavior as a notification that the vehicle is in an inappropriate traveling state when entering a curved road, the driver can use the deceleration behavior in an appropriate traveling state, that is, an appropriate traveling state when the vehicle enters the curved road. It is possible to recognize that the vehicle is not running at the speed.
As described above, when the driver's required driving force Fd corresponding to the accelerator pedal depression amount is equal to or more than the correction amount Fc (Fd ≧ Fc), Fd−Fc ≧ 0, so the correction amount Fc is set to the driving force correction amount. Even if the dry required driving force Fd is corrected (subtracted), the difference in driver required driving force remains as a control value. For this reason, when the driver request driving force Fd corresponding to the accelerator pedal depression amount is equal to or more than the correction amount Fc, the braking force correction amount is set to zero, and the correction is not performed by the braking force control device 20. A negative value of the correction amount Fc is given as a driving force correction amount, and correction is performed only by the driving force control device 10 to generate a desired repulsion force as a whole system, and the repulsion force is applied to the vehicle as running resistance. It can be said that.
[0053]
Further, the vehicle operation obtained from the relationship between the correction amount (repulsion force) Fc and the driver request driving force Fd as described above can be illustrated as shown in FIG. Here, it is assumed that the accelerator opening is kept constant.
That is, when the vehicle 300 approaches the curved road and the distance Lrs to the curved road entrance point Cs reaches a certain distance, the correction amount Fc is generated and the curve Lc is generated as shown in FIG. As the distance Lrs to the road entrance point Cs decreases, the repulsive force F, that is, the correction amount Fc increases. On the other hand, at this time, since the accelerator opening is constant, the driver required driving force Fd takes a constant value regardless of the distance Lrs to the curve road entrance point Cs, as shown in FIG.
[0054]
Here, as shown in FIG. 13 (c), the actual braking / driving force obtained as the difference value (Fd−Fc) between the driver required driving force Fd and the correction amount (repulsion force) Fc reaches the curve road entrance point Cs. Until the distance Lrs becomes a certain distance, the value of the driver requested driving force Fd itself becomes a value, but when the distance Lrs becomes shorter than a certain distance, it decreases. Then, when the distance Lrs is further reduced, the actual driving force reaches a negative value. In such a case, the driving torque is reduced by correcting the driving force control amount in the driving force control device 10 in a region where the actual braking driving force is a positive value in a region where the actual braking driving force is reduced. In a region where the value decreases and a region where the value is a negative value, the braking / driving force control amount of the driving force control device 10 is corrected to increase the braking force.
[0055]
FIG. 14 shows characteristics of the driving force and the braking force by the correction based on the correction amount Fc.
As shown in FIG. 14, when the accelerator pedal depression amount is large, the driving force (driver required driving force) corresponding to the accelerator pedal depression amount is corrected in the decreasing direction by the correction amount Fc (characteristic shown as B in the figure). On the other hand, when the accelerator pedal depression amount is small, a correction is made so that a driving force (driver required driving force) according to the accelerator pedal depression amount is not generated (the driver required driving force is corrected to zero) (in the figure). (Characteristic indicated by C), and correction is made so that a braking force that decreases with an increase in the accelerator pedal depression amount is generated (characteristic indicated by D in the figure). Further, when the brake pedal 3 is depressed, the braking force is corrected based on the correction amount Fc in the direction in which the braking force increases (the characteristic shown as E in the figure), so that the running resistance of the vehicle as a whole corresponds to the correction amount Fc. Increase.
[0056]
In this manner, the virtual repulsive force of the elastic body is calculated according to the presence or absence of a curved road ahead of the host vehicle, and the repulsive force is used as an absolute correction amount to realize the absolute correction amount. Since the force correction amount and the braking force correction amount are output to the driving force control device 10 and the braking force control device 20, respectively, and the driver requested driving force and the driver requested braking force are corrected, the own vehicle enters a curved road ahead. When the vehicle is in a traveling state that is determined to be inappropriate for stable traveling, the driver is requested to reduce the acceleration level in accordance with the repulsive force or to decelerate the host vehicle. Since it was notified that it was an inappropriate traveling state, by taking measures such as decelerating at this point, it is possible to enter with sufficiently decelerated state when actually entering the curve road, Safe on curved roads It is possible to travel.
[0057]
Also, at this time, a virtual elastic body is assumed in front of the host vehicle, and the repulsive force increases as the host vehicle approaches the curve entrance point Cs, that is, the vehicle travels as the host vehicle approaches the curve entrance point Cs. Resistance increases. Therefore, the running resistance is continuously changed so that the host vehicle is predicted to enter the curve entrance point Cs in an inappropriate running state, and the driver is notified of the approach to the curved road. Therefore, the driver can estimate the degree of approach to a curved road and the degree of improper running state according to the magnitude of the running resistance.
[0058]
Also, at this time, the curve approaching vehicle speed V ^* Is set to be smaller as the curve entrance radius R becomes smaller. Therefore, the curve entry radius R becomes smaller, and the more the vehicle needs to enter at a lower vehicle speed, the more the curve entry vehicle speed V ^* Becomes smaller. That is, since the control is performed such that the repulsive force F is generated at an earlier stage, the repulsive force F can be generated at a timing suitable for the curve shape ahead of the host vehicle. Also, the vehicle speed V when entering the curve ^* As the difference between the vehicle speed and the traveling vehicle speed Vc is larger, the repulsive force F is calculated to be a larger value, so that the repulsive force F suitable for the curve shape ahead of the host vehicle can be generated.
[0059]
Also, at this time, even if a curved road exists in front of the host vehicle, the vehicle speed V when entering the curve is set. ^* Is compared with the traveling vehicle speed Vc, and the vehicle speed V entering the curve is obtained. ^* Is generated only when the vehicle speed is higher than the traveling vehicle speed Vc. Therefore, in a state where the vehicle can run on a curved road stably in the current traveling state, it is unnecessary to generate the repulsive force. The notification can be performed only when it is determined that stable running is not possible, which is necessary to notify the user of entering a curved road.
[0060]
Next, a second embodiment of the present invention will be described.
The second embodiment is the same as the first embodiment except that the process of calculating the pass margin is different. Therefore, the same reference numerals are given to the same portions, and the detailed description thereof will be omitted. Omitted.
FIG. 15 is a flowchart illustrating an example of a processing procedure of a pass margin calculation process according to the second embodiment.
[0061]
In the second embodiment, first, in step S12, similarly to the above-described first embodiment, the target lateral acceleration Yg at the time of entering the curve is set. ^* Is set to, for example, about 0.4 G.
Next, the process proceeds to step S24, and based on the navigation information from the navigation device 40, as shown in FIG. 10, a curve radius (hereinafter, referred to as a curve minimum radius) Rmin at a curve minimum point Cmin where the curve radius is minimum. , The distance Lrmin from the vehicle to the curve minimum point Cmin is specified, and the traveling speed Vc of the vehicle is calculated based on the detection signals of the wheel speed sensors 1FL to 1RR.
[0062]
Next, the process proceeds to step S26, and based on the following equation (5), the curve approaching vehicle speed V ^* Is calculated.
V ^* = (Yg ^* × Rmin) ^1/2 …… (5)
Next, the process proceeds to step S28, in which the collision speed TTC is calculated as a pass margin for the minimum radius of the curve. Specifically, the traveling speed Vc of the own vehicle is the vehicle speed V approaching the curve. ^* Is larger than (Vc> V ^* ), And calculates the collision speed TTC based on the following equation (6). On the other hand, if the traveling speed Vc of the own vehicle is ^* When Vc ≦ V ^* ), The TTCmax is set as the collision speed TTC.
[0063]
TTC = Lrmin / (Vc−V ^* ) …… (6)
That is, in the second embodiment, the curve minimum point Cmin is used as a reference point for generating a repulsive force. That is, when the vehicle passes through the curve minimum point Cmin where the curve radius becomes minimum, it is determined whether or not the vehicle is in a traveling state in which stable traveling is possible. Therefore, even when the radius of the curve is extremely small in the middle of the curve, for example, to the curve entrance, at a point in time before entering the curve, it is notified that the vehicle is in an inappropriate traveling state for stable traveling, In response to this, the driver can perform a deceleration operation or the like, and can enter a curved road in a state where the vehicle has been decelerated to a traveling state in which stable traveling can be performed when passing the point Cmin where the curve radius is the minimum. Even when the vehicle passes the curve minimum point Cmin, the vehicle can run stably.
[0064]
Next, a third embodiment of the present invention will be described.
The third embodiment is a combination of the first embodiment and the second embodiment, except that the processing for calculating the margin is different from that of the first embodiment. Are the same, the same reference numerals are given to the same parts, and the detailed description thereof will be omitted.
[0065]
As shown in FIG. 16, in the process of calculating the passage allowance in the third embodiment, first, in step S12, the target lateral acceleration Yg at the time of entering a curve is determined. ^* Set.
Next, the process proceeds to step S10, in which the processing of steps S14 to S18 in FIG. ^* And the margin TTC are calculated, and this is calculated as the vehicle speed Vs entering the curve. ^* And the allowance TTCs.
[0066]
Next, the process proceeds to step S20 to perform the processes of steps S24 to S28 in FIG. ^* And the margin TTC are calculated, and this is calculated as the curve approaching vehicle speed Vmin. ^* And the allowance TTCmin.
Next, the process proceeds to step S32, in which the margin TTCs for the curve entrance point Cs calculated in step S10 and the margin TTCmin for the curve minimum point Cmin calculated in step S20 are compared, and the margin for the curve entrance point Cs is compared. If TTCs is smaller than the margin TTCmin for the curve minimum point Cmin (TTCs <TTCmin), the process proceeds to step S34, and the margin TTCs for the curve entrance point Cs is set as the margin TTC. Curve entry speed Vs with respect to curve entrance point Cs ^* To the curve entry vehicle speed V ^* Set as
[0067]
On the other hand, in step S32, if the passage allowance TTCs for the curve entrance point Cs is equal to or greater than the passage allowance TTCmin for the curve minimum point Cmin (TTCs ≧ TTCmin), the flow shifts to step S36, where the passage allowance for the curve minimum point Cmin is obtained. The degree TTCmin is set as the passing allowance TTC, and the curve approaching vehicle speed Vmin with respect to the curve minimum point Cmin is set. ^* To the curve entry vehicle speed V ^* Set as
[0068]
Then, the margin TTC and the vehicle speed Vmin entering the curve set in this manner. ^* Based on the above, processing is performed in the same manner as in the above embodiment.
That is, in the third embodiment, the curve entrance point Cs and the curve minimum point Cmin are used as reference points for generating a repulsive force. Therefore, when the vehicle passes through the curve entrance point Cs and the curve minimum point Cmin, it is determined whether or not the vehicle is in a traveling state in which stable traveling is possible. Is extremely small, the curve entry point Cs is also controlled, and the repulsion force F is generated as needed at a point before the curve entry point Cs. And the driver can be given a sense of security.
[0069]
In each of the above-described embodiments, a case has been described in which the presence / absence of a curved road ahead of the host vehicle and information relating thereto are acquired from the navigation device 40 based on the navigation information. However, the present invention is not limited to this. Any road shape detecting means capable of acquiring road shape information ahead of the own vehicle can be applied. As the road shape detecting means, for example, a reflector group detecting means for identifying a reflector group attached to a guard rail on a curved road is provided by a laser radar for scanning a running path in front of the vehicle, and the reflector group detecting means A forward curve shape may be estimated based on the detected reflector group position information based on the position information of the reflector group.
[0070]
Further, as the road shape detecting means, a front object detecting means such as a laser radar for detecting a preceding vehicle ahead of the own vehicle is provided, and the yaw of the preceding vehicle traveling ahead of the own vehicle detected by the front object detecting means is provided. The corner may be detected by a known procedure, and the curve shape ahead may be estimated based on the detected angle.
Further, as the road shape detecting means, an image pickup means such as a CCD camera for picking up an image of a traveling road ahead of the host vehicle is provided, and a road white line is detected by a known procedure in an image picked up by the image pickup means. Alternatively, the shape of the curve ahead may be estimated. At this time, a delineator may be detected from the captured image, and a forward curve shape may be estimated based on the detected delineator.
[0071]
Further, as the road shape detecting means, an infrastructure information communication means for obtaining infrastructure information from infrastructure facilities provided on the road surface side is provided, and various information such as the presence or absence of a curved road and a curve shape is obtained as the infrastructure information. You may do so.
Further, once the distance to the curve entry point Cs or the curve minimum point Cmin is obtained from the road shape detecting means, the travel speed Vc of the own vehicle is obtained. The distance to each point may be estimated based on the front object detection sensor that detects an object in front of the host vehicle, and periodically inputs front object information from the front object detection sensor. Alternatively, the distance to each point may be obtained from the preceding object information based on the position of each point specified by the distance information from the road shape detection unit once notified.
[0072]
Further, in each of the above-described embodiments, a case has been described in which, on a curved road ahead of the vehicle, whether or not the vehicle is in an appropriate traveling state is determined when passing through the curved road. Instead, for example, a road condition such as a road surface condition in front of the host vehicle or an obstacle present in front of the host vehicle is detected, and it is determined whether or not the vehicle is in an appropriate running state with respect to the road shape. Notification may be performed according to the determination result.
[0073]
In the first embodiment, the process of acquiring the curve entrance radius Rs and the distance Lrs to the curve entrance point in the navigation device 40 in step S14 of FIG. 9 corresponds to the road shape detection means. The process of calculating the traveling speed Vc of the host vehicle corresponds to the traveling speed detecting means, the processes of steps S16 and S18 correspond to the passing margin estimating means, and the processes of steps S5 to S9 in FIG. It corresponds to.
[0074]
In the second embodiment, the navigation device 40 performs the process of acquiring the minimum curve radius Rmin and the distance Lrmin to the minimum curve point in step S24 in FIG. The process of calculating the traveling speed Vc of the vehicle corresponds to the traveling speed detecting means, the processes of steps S26 and S28 correspond to the passing margin estimating means, and the processes of steps S5 to S9 in FIG. It corresponds to.
[0075]
In the third embodiment, the navigation device 40 acquires the curve entrance radius Rs and the distance Lrs to the curve entrance point in step S10 in FIG. 16 and the curve minimum radius Rmin and the curve minimum point in step S20. The process of acquiring the distance Lrmin to the road corresponds to the road shape detecting means, the process of calculating the margin TTCs in step S10, and the process of acquiring the margin TTCmin in step S20 corresponds to the margin estimating means. The processing in steps S5 to S9 in FIG. 8 corresponds to the appropriate notification unit.
[0076]
In the above embodiment, the road shape detecting means detects a curve shape in front of the own vehicle and a distance from the own vehicle to the curve, and the passing margin detecting means detects the curve shape according to the curve shape. An approach vehicle speed is detected, and a value obtained by dividing a distance from the own vehicle to the curve by a deviation between the approach vehicle speed and the traveling speed detected by the traveling speed detecting means is used as the index of the margin of passage. With this configuration, the suitability can be notified only for the overspeed with respect to the curve ahead of the host vehicle, and the suitability can be determined based on the curve shape.
[0077]
Further, the passage margin detecting means detects the curve radius of the curve entrance based on the curve shape and detects the approaching vehicle speed suitable for the curve radius. Appropriateness can be determined, and accordingly, the driver can be alerted before entering the curve.
Further, since the passing margin detecting means detects the minimum radius of the curve based on the curve shape and detects the approaching vehicle speed suitable for the minimum radius of the curve, the curve shape changes in the middle of the curve. Even in such a case, it is possible to make a proper judgment appropriately according to the curve state, and it is possible to surely call the driver's attention.
[0078]
Further, the passage margin detecting means detects a curve radius of the curve entrance based on the curve shape and detects a minimum radius of the curve, and is suitable for each of the curve radius of the curve entrance and the minimum radius of the curve. The passing vehicle speed is detected by detecting the entering vehicle speed, and the appropriate informing means is the smaller of the passing margin corresponding to the curve entrance and the passing margin corresponding to the curve minimum radius. , The appropriateness can be determined according to the curve state at the curve entrance, and accordingly, the driver is warned in advance before entering the curve. In addition to the above, even when the curve shape changes in the middle of the curve, it is possible to make an appropriate determination accurately in accordance with the curve state.
[0079]
Further, the road shape detecting means is configured to detect a road shape ahead of the own vehicle based on road information stored in a navigation device mounted on the own vehicle. The road shape ahead of the vehicle can be easily obtained.
Further, the road shape detecting means has a reflector group detecting means capable of detecting a positional relationship between the reflector group disposed along the curve and the host vehicle, and the reflector group detected by the reflector group detecting means is provided. Since the configuration of the road shape is detected based on the arrangement status, it is possible to easily detect whether or not the road is a curved road and the shape thereof based on the arrangement status of the reflector group.
[0080]
Further, the road shape detecting means includes a front object detecting means capable of detecting a distance between the front object and the own vehicle, and detects a yaw angle of the preceding vehicle based on detection information of the front object detecting means, and Since the road shape is detected based on the yaw angle of the preceding vehicle, it is possible to easily detect whether or not the preceding vehicle is traveling on a curved road and its shape based on the yaw angle of the preceding vehicle.
Further, the road shape detecting means has an image pickup means for picking up an image of a traveling road ahead of the host vehicle, detects a road white line from an image picked up by the image pickup means, and detects the road shape based on the shape of the road white line. With this configuration, the actual road shape can be easily detected based on the shape of the road white line.
[Brief description of the drawings]
FIG. 1 is a schematic configuration diagram illustrating an example of a travel control system according to the present invention.
FIG. 2 is a block diagram showing a configuration of the driving force control device of FIG.
FIG. 3 is a characteristic map showing a correspondence between an accelerator pedal depression amount and a driver required driving force.
FIG. 4 is a block diagram illustrating a configuration of a braking force control device of FIG. 1;
FIG. 5 is a characteristic map showing a correspondence between a brake pedal depression amount and a driver's requested braking force.
FIG. 6 is a block diagram illustrating a configuration of the navigation device in FIG. 1;
FIG. 7 is a functional configuration diagram illustrating an example of a functional configuration of a notification control controller of FIG. 1;
FIG. 8 is a flowchart illustrating an example of a processing procedure of a calculation process performed by the notification control controller.
FIG. 9 is a flowchart illustrating an example of a processing procedure of a passage allowance calculation process in FIG. 8 according to the first embodiment.
FIG. 10 is an explanatory diagram for explaining a curve entry point Cs and a curve minimum point Cmin.
FIG. 11 is an explanatory diagram required for describing a model for calculating a correction amount, in which a virtual elastic body is provided at a front portion of the host vehicle.
FIG. 12 is a flowchart illustrating an example of a processing procedure of braking / driving force correction amount calculation processing in FIG. 8;
FIG. 13 is an explanatory diagram for explaining the operation of the present invention;
FIG. 14 is an explanatory diagram for explaining a change state of a braking force and a driving force accompanying a correction.
FIG. 15 is a flowchart illustrating an example of a processing procedure of a passage allowance calculation process in FIG. 8 according to the second embodiment.
FIG. 16 is a flowchart illustrating an example of a processing procedure of a passage allowance calculation process of FIG. 8 according to the third embodiment.
[Explanation of symbols]
1FL-1RR Wheel speed sensor
3 brake pedal
4 accelerator pedal
5 Notification controller
6 Engine
10 Driving force control device
20 Braking force control device
30 Navigation device

Claims (9)

Road shape detecting means for detecting a road shape in front of the host vehicle;
Traveling speed detection means for detecting the traveling speed of the own vehicle,
Based on the road shape in front of the vehicle detected by the road shape detection means and the traveling speed detected by the traveling speed detection means, the passing margin of the own vehicle when passing through a location corresponding to the road shape is determined. Passing margin estimating means for estimating,
Based on the pass margin, determine the appropriateness of the traveling state of the host vehicle when passing through a location corresponding to the road shape, and change at least one of the driving torque or the braking torque according to the determination result. A vehicle notification device, comprising: a proper notification unit that performs the notification of the appropriateness by applying a braking force to the host vehicle. The road shape detecting means detects a curve shape ahead of the vehicle and a distance from the vehicle to the curve,
The passing margin detecting means detects an approaching vehicle speed according to the curve shape, and determines a distance from the own vehicle to the curve by a deviation from the approaching vehicle speed and the traveling speed detected by the traveling speed detecting means. 2. The vehicle alarm device according to claim 1, wherein the divided value is used as an index of the passing margin. 3. The vehicle according to claim 2, wherein the passage allowance detecting means detects a curve radius at a curve entrance based on the curve shape, and detects the approaching vehicle speed suitable for the curve radius. Notification device for vehicles. 3. The vehicle according to claim 2, wherein the passing margin detecting means detects a minimum radius of the curve based on the curve shape, and detects the approaching vehicle speed suitable for the minimum radius of the curve. Notification device for vehicles. The passage margin detecting means detects a curve radius of a curve entrance based on the curve shape and detects a minimum radius of the curve, and the approach suitable for each of the curve radius of the curve entrance and the minimum radius of the curve. Detecting the vehicle speed and detecting the passing margin,
The appropriateness informing means is configured to determine the appropriateness based on the smaller one of the passage margin corresponding to the curve entrance and the passage margin corresponding to the curve minimum radius. The vehicle alarm device according to claim 2, wherein: 6. The road shape detecting means according to claim 1, wherein the road shape detecting means detects a road shape ahead of the own vehicle based on road information stored in a navigation device mounted on the own vehicle. A vehicle notification device according to any one of claims 1 to 3. The road shape detecting means has a reflector group detecting means capable of detecting a positional relationship between the own vehicle and a reflector group arranged along a curve,
The vehicle alarm device according to any one of claims 1 to 6, wherein the road shape is detected based on an arrangement state of the reflector group detected by the reflector group detection means. The road shape detection unit has a front object detection unit capable of detecting a distance between the front object and the own vehicle,
8. The vehicle according to claim 1, wherein a yaw angle of a preceding vehicle is detected based on detection information of said front object detecting means, and said road shape is detected based on a yaw angle of said preceding vehicle. The vehicle notification device according to any one of the above. The road shape detecting means has an imaging means for imaging a traveling road ahead of the own vehicle,
The vehicle according to any one of claims 1 to 8, wherein a road white line is detected from an image captured by the imaging unit, and the road shape is detected based on a shape of the road white line. Notification device.

Images