JP5206138B2 - Vehicle deceleration control device - Google Patents

Description

The present invention relates to a vehicle deceleration control equipment for deceleration control of the vehicle to the vehicle ahead of the curve.

Conventionally, there is a technique for detecting the state of a curve in front of the vehicle and performing deceleration control based on the detected state of the curve in front of the vehicle. In the device disclosed in Patent Document 1, a target vehicle speed in a forward curve is calculated using a plurality of node points provided by the navigation system, and a target deceleration is calculated based on the calculated target vehicle speed and the own vehicle speed. Yes. In this apparatus, the deceleration control is activated when the calculated target deceleration reaches a predetermined value.
JP-A-6-36187

By the way, the node points provided by the navigation system are densely provided on curved roads, but generally coarsely provided on other roads. Therefore, when specifying a curve using a plurality of node points as in the device of Patent Document 1, depending on the relationship between the node points in the vicinity of the branch point, the curve is detected as a curve having a smaller curvature than the actual curvature. Since the deceleration control different from the curvature of the curve is activated, the deceleration control may give the driver a sense of incongruity.
An object of the present invention is to perform deceleration control in conformity with the state of a curve at a branch point.

  In order to solve the above problem, the present invention corrects the target deceleration based on the density of node points within a predetermined range of a branch point ahead of the vehicle.

  According to the present invention, the road shape at the branch point can be appropriately evaluated by correcting the degree of suppression of the target deceleration based on the density of the node points within the predetermined range of the branch point ahead of the vehicle. Deceleration control can be implemented by adapting to the state of the curve.

The best mode for carrying out the present invention (hereinafter referred to as an embodiment) will be described in detail with reference to the drawings.
(First embodiment)
(Constitution)
1st Embodiment is a rear-wheel drive vehicle carrying the vehicle deceleration control apparatus which concerns on this invention. This rear-wheel drive vehicle is equipped with an automatic transmission and a conventional differential gear, and a braking device capable of independently controlling the braking force of the left and right wheels for both the front and rear wheels.
FIG. 1 is a schematic configuration diagram showing the present embodiment. In the figure, reference numeral 1 is a brake pedal, 2 is a booster, 3 is a master cylinder, and 4 is a reservoir. Usually, the brake fluid pressure is increased by the master cylinder 3 in accordance with the depression amount of the brake pedal 1 by the driver, and the increased brake fluid pressure is supplied to the wheel cylinders 6FL to 6RR of the wheels 5FL to 5RR. Further, a brake fluid pressure control unit 7 is interposed between the master cylinder 3 and each wheel cylinder 6FL to 6RR.

  The braking fluid pressure control unit 7 uses a braking fluid pressure control unit used for antiskid control and traction control, for example. The braking fluid pressure control unit 7 individually controls the braking fluid pressures of the wheel cylinders 6FL to 6RR. And the brake fluid pressure control part 7 can control the brake fluid pressure independently. Further, when a braking fluid pressure command value is input from a braking / driving force control unit 8 described later, the braking fluid pressure control unit 7 can also control the braking fluid pressure according to the braking fluid pressure command value. . For example, the brake fluid pressure control unit 7 includes an actuator in the hydraulic pressure supply system. Examples of the actuator include a proportional solenoid valve capable of controlling each wheel cylinder hydraulic pressure to an arbitrary braking hydraulic pressure.

  Further, this vehicle is equipped with a drive torque control unit 12. The drive torque control unit 12 controls the drive torque to the rear wheels 5RL and 5RR which are drive wheels by controlling the operating state of the engine 9, the selected gear ratio of the automatic transmission 10, and the throttle opening of the throttle valve 11. To do. The drive torque control unit 12 controls the operating state of the engine 9 by controlling the fuel injection amount and ignition timing, and simultaneously controlling the throttle opening. The drive torque control unit 12 can also independently control the drive torque of the rear wheels 5RL and 5RR. Further, when a driving torque command value is input from the braking / driving force control unit 8, the driving torque control unit 12 can also control the driving wheel torque according to the driving torque command value. The drive torque control unit 12 outputs the value of the drive torque Tw used for control to the braking / driving force control unit 8.

  In addition, this vehicle is equipped with an external recognition sensor 13 for detecting a preceding vehicle. The external recognition sensor 13 includes a millimeter wave radar 13a and a millimeter wave radar controller 13b. In the external recognition sensor 13, the millimeter wave radar controller 13b detects the inter-vehicle distance Lx to the preceding vehicle based on the detection result of the millimeter wave radar 13a. The outside recognition sensor 13 outputs the inter-vehicle distance Lx to the braking / driving force control unit 8.

The vehicle is equipped with a navigation device 14. The navigation device 14 searches for the road information ahead of the host vehicle based on the host vehicle position (X ₀ , Y ₀ ) measured by GPS (Global Positioning System) and map information (electronic map). Here, the road information ahead of the host vehicle is so-called node point information. The node point information includes X _j , Y _j , L _j , and Branch _j (j = 1 to n, n is an integer). X _j and Y _j are position information of the node point N _j . L _j is a distance from the vehicle position (X ₀ , Y ₀ ) to the position (X _j , Y _j ) of an arbitrary node point N _j . Branch _j is information indicating whether or not it is a branch point. As for the relationship between the node points N _j, the larger the value of j, the farther the node point N _j is from the position (X ₀ , Y ₀ ) of the host vehicle. The navigation device 14 outputs a map display, the current vehicle position, and the like to an output unit such as a monitor based on such node point information (X _j , Y _j , L _j , Branch _j ) and the like. Similar information can also be obtained from an infrastructure facility installed in front of the curve by road-to-vehicle communication.

This vehicle is equipped with a warning monitor 15. The warning monitor 15 has a built-in speaker for generating sound and buzzer sound. The braking / driving force control unit 8 controls the operation of the warning monitor 15.
Further, the vehicle includes an acceleration sensor 16 that detects longitudinal acceleration Yg and lateral acceleration Xg, a yaw rate sensor 17 that detects yaw rate φ ′, an accelerator opening sensor 18 that detects an accelerator pedal depression amount, that is, an accelerator opening θt, A steering angle sensor 19 for detecting the steering angle δ of the steering wheel 21, a master cylinder pressure sensor 20 for detecting the output pressure of the master cylinder 3, that is, the master cylinder hydraulic pressure Pm, the rotational speeds of the wheels 5FL to 5RR, and the so-called wheel speed. Wheel speed sensors 22FL to 22RR for detecting Vwi (i = fl, fr, rl, rr) are mounted. These sensors and the like output detected signals and the like to the braking / driving force control unit 8.

  Further, this vehicle is equipped with an ACC switch 23 for ACC (adaptive cruise control). For example, the ACC switch 23 is attached to the steering wheel or the vehicle body. The ACC switch 23 includes a plurality of switches such as a main switch (MAIN SW), a reset switch (RES SW), and a set switch (SET SW). For example, when the set switch is pressed while the main switch is set, the ACC switch 23 outputs the host vehicle speed at that time as the set vehicle speed. The set vehicle speed is a vehicle speed for performing constant speed running.

  FIG. 2 shows a configuration example of the braking / driving force control unit 8. As shown in the figure, the braking / driving force control unit 8 includes a vehicle speed calculation unit 41, a target vehicle speed calculation unit 42, a navigation information processing unit 43, a target deceleration calculation unit 44, a target vehicle speed command value calculation unit 45, and an alarm control unit. 46, a vehicle speed setting unit 47, a vehicle speed command value calculation unit 48, a vehicle speed servo calculation unit 49, and a torque distribution control calculation unit 50. The torque distribution control calculation unit 50 includes a brake fluid pressure calculation unit 51 and an engine torque calculation unit 52. The braking / driving force control unit 8 can also include these components in the form of software, for example.

  FIG. 3 shows a processing procedure of arithmetic processing performed by the braking / driving force control unit 8. The processing procedure will be described together with the processing contents of the components shown in FIG. 2 with reference to FIG. The braking / driving force control unit 8 executes this calculation process by timer interruption every predetermined sampling time ΔT every 10 msec., For example. Information obtained by the arithmetic processing is updated and stored in the storage device as needed, and necessary information is read from the storage device as needed.

As shown in FIG. 3, when the process is started, first in step S1, the braking / driving force control unit 8 reads various data from the sensors, the controller, the control unit, and the like. Specifically, the node point information (X _j , Y _j , L _j , Branch _j ) (j = 1 to n) obtained by the navigation device 14 is read. Further, each wheel speed Vwi, steering angle δ, accelerator opening θt, master cylinder hydraulic pressure Pm, and driving torque Tw from the driving torque control unit 12 detected by each sensor or the like are read. Further, the set vehicle speed is read from the ACC switch 23.

Subsequently, in step S2, the vehicle speed calculation unit 41 calculates the vehicle speed V. Specifically, the vehicle speed calculation unit 41 calculates the vehicle speed V by the following equation (1) based on the wheel speed Vwi read in step S1.
For front wheel drive V = (Vwr1 + Vwrr) / 2
For rear wheel drive V = (Vwfl + Vwfr) / 2
... (1)
Here, Vwfl and Vwfr are the wheel speeds of the left and right front wheels. Vwrl and Vwrr are the wheel speeds of the left and right rear wheels, respectively. In the equation (1), the vehicle speed V is calculated as an average value of the wheel speeds of the driven wheels. In this embodiment, since the vehicle is a rear-wheel drive vehicle, the vehicle speed V is calculated from the latter equation, that is, the wheel speed of the front wheels.

The vehicle speed V calculated in this way is preferably used during normal travel. Further, when an ABS (Anti-lock Brake System) control or the like is operating, an estimated vehicle speed estimated in the ABS control can be used as the vehicle speed V. A value used for navigation information in the navigation device 14 can also be used as the vehicle speed V.
Subsequently, in step S3, the navigation information processing unit 43 calculates the turning radius of each node point ahead of the host vehicle. Specifically, the navigation information processing unit 43 determines each node point based on the coordinates (X _j , Y _j ) (j = 1 to n) of the node points that are the node point information of the forward road read in step S1. Calculate the turning radius of the node point. There are several methods for calculating the turning radius. In the present embodiment, the coordinates (X _j−1 , Y _j−1 ), (X _j , Y _j ), (X _{j + 1} , Y _{j + 1} ) of three consecutive node points are expressed by the following equation (2). ) To calculate the turning radius R _j .
R _j = f ₁ (X _j−1 , Y _j−1 , X _j , Y _j , X _{j + 1} , Y _{j + 1} ) (2)

As shown in FIG. 4, continuous node points N _j-1 (X _j−1 , Y _j−1 ), node points N _j (X _j , Y _j ), node points N _{j + 1} (X _{j + 1)} , Y _{j + 1} ), the turning radius R _j is calculated. Here, the function f1 is a function for calculating the turning radius from the coordinates of the three node points. When the turning radius R _j is a negative value, it indicates a left turn, and when the turning radius R _j is a positive value, it indicates a right turn. For example, as shown in FIG. 5, for each node point N _j (node point number), a turning radius R _j (● mark in the figure) can be obtained.

Here, a method of calculating the turning radius from the coordinates (X _j−1 , Y _j−1 ), (X _j , Y _j ), and (X _{j + 1} , Y _{j + 1} ) of the three points is shown. However, the turning radius can also be calculated using an angle formed by a straight line connecting the preceding and following node points. Here, the turning radius is calculated based on the coordinates of each node point. However, the turning radius of each node point can be stored as node point information in the map data, and the value can be retrieved in this step S3. It is also possible to create complementary points that divide each node point at equal intervals so as to pass through each node point, and calculate the turning radius for each of the created complementary points.

Subsequently, in step S4, the target vehicle speed calculation unit 42 calculates the target vehicle speed at each node point. Specifically, the target vehicle speed calculation unit 42 calculates the target vehicle speed Vr _j by the following equation (3) using the turning radius R _j and the allowable lateral acceleration Yglimt of each node point calculated in step S3.
Vr _j = √ (Yglimt · | R _j |) (3)
Here, the allowable lateral acceleration Yglimt is a predetermined value, for example, 0.3 g. Further, the driver can set the allowable lateral acceleration Yglimt by a selection changeover switch. According to the equation (5), the target vehicle speed Vr _j increases as the allowable lateral acceleration Yglimt increases. It is also possible to create complementary points that divide each node point at equal intervals so as to pass through each node point, and calculate the target vehicle speed for each of the created complementary points.

Subsequently, in step S5, the target deceleration calculation unit 44 calculates a target deceleration. Specifically, the target deceleration calculation unit 44 determines the vehicle speed V calculated in step S2, the target vehicle speed Vr _j calculated in step S4, and the distance L _j from the current position obtained by the navigation device 14 to the node point. The target deceleration Xgs _j is calculated using the following equation (4).
Xgs _j = (V ² −Vr _j ² ) / (2 · Ln _j )
= (V ² -Yglmit · | R _j |) / (2 · L _j ) (4)

Here, the target deceleration Xgs _j is given as a negative value (decreases) when decelerating, and is given (increased) as a positive value when accelerating. Further, in calculating the target deceleration Xgs _j , the turning radius R _j , the distance L _j, and the target vehicle speed Vr _j are values indicating the state of the curve ahead of the vehicle. According to the equation (4), the target deceleration Xgs _j decreases as the target vehicle speed Vr _j decreases (increases in absolute value). That is, a larger deceleration (absolute value) is required as the target vehicle speed Vr _j becomes smaller. Alternatively, the target deceleration Xgs _j decreases (the absolute value increases) as the host vehicle speed V increases. Alternatively, the target deceleration Xgs _j decreases as the allowable lateral acceleration Yglimt decreases. Alternatively, the target deceleration Xgs _j decreases as the absolute value | R _j | of the turning radius decreases. Alternatively, the target deceleration Xgs _j becomes smaller as the distance L _j becomes shorter. It is also possible to create complementary points that divide each node point at equal intervals so as to pass through each node point, and calculate the target deceleration for each of the created complementary points.

Subsequently, in step S6, the target deceleration calculation unit 44 detects the target deceleration having the minimum value from the target deceleration Xgs _j at each node point. Specifically, the target deceleration calculation unit 44 detects the minimum value of the target deceleration (hereinafter referred to as the minimum target deceleration) Xgsmin by the following equation (5).
Xgsmin = min (Xgs _j ) (5)
Here, the function min from the target deceleration Xgs _j at each node point is a function for extracting the target deceleration Xgs _j minimum. The minimum target deceleration Xgsmin for detecting the node point (target node point) to be controlled can be obtained from the equation (5).

Subsequently, in step S7, the target vehicle speed command value calculation unit 45 calculates a target vehicle speed command value. Specifically, the target vehicle speed command value calculation unit 45 calculates the target vehicle speed command value Vrr by the following equation (6) using the minimum target deceleration Xgsmin detected in step S6.
Vrr = f2 (Xgsmin) · t (6)
Here, the function f2 is a function that limits a change in the minimum target deceleration Xgsmin. For example, the change amount limiter for limiting the change is set to 0.01 G / sec, for example. The function f2 increases the target vehicle speed command value Vrr as Xgsmin increases. t indicates time (sampling time). According to the equation (6), the target vehicle speed command value Vrr changes by an amount corresponding to the change amount limiter and time t. That is, the target vehicle speed command value to which the deceleration change amount limiter is added is calculated by the equation (6).

  Subsequently, in step S8, the alarm control unit 46 makes an alarm activation start determination. The alarm control unit 46 performs the alarm operation start determination by, for example, a function (a function for determining the alarm operation start). Specifically, the alarm control unit 46 determines to start the alarm when the minimum target deceleration Xgsmin calculated in step S6 becomes less than the alarm activation determination threshold value Xgsth1 (Xgsmin <Xgsth1). . When the alarm control unit 46 determines to activate the alarm, the alarm control unit 46 sets the alarm activation flag flg1 to 1 (flg1 = 1). For example, the threshold value Xgsth1 for alarm activation determination is an experimental value, an empirical value, or a theoretical value.

FIG. 6 shows the relationship between the minimum target deceleration Xgsmin and the alarm activation flag flg1. As shown in the figure, when the minimum target deceleration Xgsmin becomes less than the alarm activation determination threshold Xgsth1 (Xgsmin <Xgsth1), the alarm activation flag flg1 becomes 1 (flg1 = 1).
Subsequently, in step S9, the vehicle speed command value calculation unit 48 determines whether to start the deceleration control operation. The vehicle speed command value calculation unit 48 makes a deceleration control operation start determination using, for example, a combined function (a function for determining the start of deceleration control operation). Specifically, the vehicle speed command value calculation unit 48 starts operating the deceleration control when the minimum target deceleration Xgsmin calculated in step S6 becomes less than the deceleration control operation determination threshold value Xgsth2 (Xgsmin <Xgsth2). Make a decision. When the vehicle speed command value calculation unit 48 determines to operate the deceleration control, it sets the deceleration control operation flag flg2 to 1 (flg2 = 1). For example, the deceleration control operation determination threshold value Xgsth2 is an experimental value, an empirical value, or a theoretical value.

  Further, the threshold value Xgsth2 for determining the deceleration control operation is set to a value smaller than the threshold value Xgsth1 for alarm operation determination for determining the start of alarm operation (Xgsth2 <Xgsth1), so that the minimum target deceleration is achieved. When Xgsmin becomes smaller, it is first determined to activate an alarm and then to determine to operate deceleration control.

FIG. 7 shows the relationship between the minimum target deceleration Xgsmin and the deceleration control operation flag flg2. As shown in the figure, when the minimum target deceleration Xgsmin becomes less than the deceleration control operation flag flg2 (Xgsmin <Xgsth2), the deceleration control operation flag flg2 becomes 1 (flg2 = 1). That is, as the target vehicle speed Vr _j decreases or the distance L _j decreases, the minimum target deceleration Xgsmin decreases (see equations (4) and (5) above), so the deceleration control operation flag flg2 becomes 1. It becomes easy.

Subsequently, in step S10, the vehicle speed servo calculation unit 49 calculates a target acceleration / deceleration. The target acceleration / deceleration is a control amount for achieving the target vehicle speed command value Vrr calculated in step S7. Specifically, when the deceleration control operation flag flg2 becomes 1, that is, when it is determined that the deceleration control is to be activated, the vehicle speed servo calculation unit 49 sets the target acceleration / deceleration in order to achieve the target vehicle speed command value Vrr. calculate. For example, the target acceleration / deceleration is calculated as a difference value between the target vehicle speed command value Vrr and the host vehicle speed V.
Subsequently, in step S11, the torque distribution control calculation unit 50 calculates torque distribution. Specifically, the torque distribution control calculation unit 50 calculates the torque distribution of the brake torque and the engine torque so that the target acceleration / deceleration calculated in step S10 is realized by the brake torque and the engine torque. Specifically, the calculation is performed as follows.

In order to realize the brake torque, the brake fluid pressure calculation unit 51 calculates a target brake fluid pressure for each wheel. Specifically, the brake fluid pressure calculation unit 51 calculates the target control fluid pressure using the target acceleration / deceleration calculated in step S10 when it is determined to start the deceleration control (flg2 = 1). For example, the brake hydraulic pressure calculation unit 51 calculates the control target hydraulic pressure Ps by the following equation (7) using the target acceleration / deceleration Xg ^* .
Ps = Kb · Xg ^* (7)
Here, Kb is a constant determined from brake specifications and the like. According to the equation (7), the control target hydraulic pressure Ps increases as the target acceleration / deceleration Xg ^* increases. The control target hydraulic pressure Pc is realized by the respective target brake hydraulic pressures Psfr and Psrr for the front and rear wheels (for example, Psfr = Psrr = Ps / 2).

Further, in order to realize the engine torque, the engine torque calculation unit 52 calculates the driving force of the driving wheels. Specifically, when the engine torque calculation unit 52 determines to start the deceleration control (flg2 = 1), the target drive is performed using the control target hydraulic pressure Ps and the accelerator opening Acc according to the following equation (8). Torque Trqds is calculated.
Trqds = f3 (Acc) −f4 (Ps) (8)
Here, the function f3 (Acc) is a function for calculating the target drive torque Trqds according to the accelerator opening Acc. f4 (Ps) is a function for calculating a braking torque that is predicted to be generated by the control target hydraulic pressure Pc.

When deceleration control is not performed (flg2 = 0), the target drive torque Trqds is calculated by the following equation (9).
Trqds = f3 (Acc) (9)
From the above, when the automatic deceleration control is operating, the target drive torque Trqds is calculated according to the accelerator opening Acc and the control amount f4 (Ps) of the automatic deceleration control (equation (8)). As a result, even if the driver performs an accelerator operation during the operation of the automatic deceleration control, the engine output is reduced to prevent acceleration. When the automatic deceleration control is not operating, the target drive torque Trqds is calculated according to the accelerator opening Acc (Equation (9)).

  Subsequently, in step S12, warning and deceleration control are performed. For the alarm, the alarm control unit 46 activates the alarm monitor 15 at the timing when the alarm is activated (when flg1 becomes 1). For example, an alarm sound is output from the alarm monitor 15 to display an alarm. Not only this but an alarm can also be implemented by HUD (Head-up Display), the voice utterance from a navigation system, a navigation screen display, and a meter display. Regarding the deceleration control, the brake hydraulic pressure calculation unit 51 and the engine torque calculation unit 52 are at the timing when the determination to activate the deceleration control is made (when flg2 becomes 1), and the target braking hydraulic pressure Psi calculated in step S11. Based on (Psfr, Psrr) and the target drive torque Trqds, a control signal is output to the brake fluid pressure control unit 7 and the drive torque control unit 12. Thereby, braking force and driving force are controlled. As a result, the vehicle decelerates according to the braking force and the driving force.

  Next, a specific calculation processing procedure performed by the braking / driving force control unit 8 will be described. FIG. 8 shows the specific processing procedure. As shown in the figure, in this process, steps S21 and S22 are newly provided in addition to the process shown in FIG. Specifically, the process of step S21 is provided between the process of step S1 and the process of step S2. The process of step S22 is provided between the process of step S4 and the process of step S5. And the braking / driving force control unit 8 is provided with the branch point determination part 61 and the target vehicle speed correction | amendment part 62, as shown in FIG. 9, in order to implement | achieve these processes. Note that the branch point determination unit 61 may be provided as a configuration in the navigation information processing unit 43.

  Here, in the process shown in FIG. 8, the process denoted by the same reference numeral (step number) as the reference numeral (step number) given to the process of FIG. It is the same as the process. Further, in FIG. 9, the processing of components having the same reference numerals as those of the components in FIG. 2 is the same as the processing of components in FIG. 2 unless otherwise specified. is there.

In step S21, the branch point determination unit 61 determines a branch point. Specifically, first, the branch point determination unit 61 has a branch point on the traveling road ahead based on the node point information (X _j , Y _j , L _j , Branch _j ) obtained in the preceding process. It is determined whether or not to do. The branch point determination unit 61 sets a branch point flag flgb to 1 (flgb = 1) when there is a branch point on the traveling road ahead. Otherwise, the branch point determination unit 61 sets the branch point flag flgb to zero (flgb = 0).

  Subsequently, the branch point determination unit 61 determines whether or not the road on which the host vehicle travels becomes a branch road when the branch point can be confirmed on the forward road (flgb = 1). For example, the branch point determination unit 61 determines, based on the node point information from the navigation device 14, whether or not the road on which the host vehicle will travel is a branch road. For example, the type of travel path is associated with a line (link) connecting the node points. For example, types such as a main line, a communication path, and a junction are associated with each other. Based on such information, the branch point determination unit 61 determines whether or not the road on which the host vehicle will travel is a branch road (a road that branches from the main line).

When the branch point determination unit 61 determines that there is a branch point on the road (flgb = 1) and the road on which the host vehicle travels becomes a branch road by the above determination, The node point density (hereinafter simply referred to as node point density) Dnode is calculated. Specifically, the branch point determination unit 61 calculates the node point density Dnode by the following equation (10).
Dnode = N _k / L_branch (10)
Here, N _k (k = p to q, p and q are integers) is the number of node points between the node point N _p including the branch point and the node point N _q . L_branch is the distance before and after the branch point. The distance L_branch is a predetermined value. For example, the distance L_branch is 100 m.

In step S22, the target vehicle speed correcting section 62 corrects the target vehicle speed Vr _j obtained by calculation process of the preceding stage. Specifically, the target vehicle speed correcting section 62, when calculating the node point density DNODEs in the step S21, on the basis of the calculated node point density DNODEs, corrects the target vehicle speed Vr _j. That is, the target vehicle speed correcting section 62, there is a branch point in the travel path (flgb = 1), and runway so that the vehicle is traveling is when it comes to the branch road, corrects the target vehicle speed Vr _j. Specifically, the target vehicle speed correction unit 62 corrects the target vehicle speed Vr _j by the following equation (11).
Vr _j = f5 (Vr _j ) (11)

Here, the function f5 is a function to increase Vr _j. Specifically, the target vehicle speed Vr _j is corrected by the following equation (12).
Vr _j = Vr _j + Kvr (12)
Here, Kvr is an offset value (predetermined value). The offset value Kvr is a value having the node point density Dnode as a variable, as shown in the following equation (13).
Kvr = f6 (Dnode) (13)

  FIG. 10 shows an example of the relationship between the node point density Dnode and the offset value Kvr. As shown in the figure, in the region where the node point density Dnode is high, the offset value Kvr is a constant large value. When the node point density Dnode becomes higher than a certain value, the offset value Kvr decreases as the node point density Dnode increases. When the node point density Dnode is further increased, the offset value Kvr becomes a constant small value regardless of the node point density Dnode. An offset value Kvr is obtained based on the node point density Dnode so as to have such a relationship (the above equation (13)). That is, as a rule, the offset value Kvr is decreased as the node point density Dnode increases (the node points increase).

Then, the target vehicle speed correction unit 62 maintains (holds) the offset value Kvr for a predetermined time according to the equation (11), and then decreases it. Specifically, the target vehicle speed correction unit 62 decreases the offset value Kvr by the following equation (14).
Kvr = Kvr−Δkvr1 (14)
Here, Δkvr1 is a predetermined amount. According to the equation (14), the offset value Kvr gradually decreases in accordance with the number of repetitions of the arithmetic processing in FIG. In other words, gradually returning to pre-corrected target vehicle speed Vr _j (see the equation (3)). The predetermined time is set according to the length of the curve section when the curve is detected before and after the branch point. Here, the curve that can be detected before and after the branch point is a curve that exists on the traveling road (branch road) of the host vehicle and exists beyond the branch point when viewed from the host vehicle.

FIG. 11 shows an example of the relationship between the length of the curve section detected before and after the branch point and the predetermined time. As shown in the figure, in a region where the curve section is long, the predetermined time is a constant large value. When the curve section becomes longer than a certain value, the longer the curve section is, the shorter the predetermined time is. When the curve section length is further increased, the predetermined time becomes a constant small value regardless of the curve section length. Using such a characteristic diagram, a predetermined time is obtained based on the length of the curve section. That is, as a general rule, the longer the curve section, the shorter the predetermined time.
Then, in the subsequent processing, it performs processing using target vehicle speed Vr _j corrected. That is, in the step S5, the target deceleration Xgs _j is calculated using the corrected target vehicle speed Vr _j (see the equation (4)). By correcting the target vehicle speed Vr _j , the target deceleration Xgs _j becomes larger than the value before correction.

(Operation and action)
Operation and action are as follows.
First, according to the process shown in FIG. 3, the vehicle deceleration control device reads various data during the traveling of the vehicle (step S1) and calculates the vehicle speed V (step S2). Further, the vehicle deceleration control device calculates the turning radius R _j of each node point in front of the host vehicle, and calculates the target vehicle speed Vr _j at each node point based on the calculated turning radius R _j of each node point. Calculate (step S3, step S4). Further, the vehicle deceleration control device calculates a target deceleration Xgs _j at each node point based on the target vehicle speed Vr _j at each node point (step S5). Then, the vehicle deceleration control apparatus detects the target deceleration Xgsmin minimum value from the target deceleration Xgs _j at each node point, on the basis of the minimum target deceleration Xgsmin that the detected, calculates a target vehicle speed command value Vrr (Steps S6 and S7). Further, the vehicle deceleration control device calculates a target deceleration Xg ^* on the basis of the target vehicle speed command value Vrr, based on the target deceleration Xg ^* with the calculated, torque distribution of the braking torque and the engine torque (Ps, Trqds ) Is calculated (steps S10 and S11). On the other hand, the vehicle deceleration control device makes an alarm activation start determination and a deceleration control activation start determination based on the minimum target deceleration Xgsmin (steps S8 and S9). Then, the vehicle deceleration control device performs the alarm and deceleration control based on the determination result of the alarm operation start determination and the deceleration control operation start determination (states of flg1 and flg2) (step S12).

On the other hand, with the processing shown in FIG. 8, when the vehicle deceleration control device has a branch point on the front traveling road and the traveling road on which the vehicle travels becomes a branch road, the vehicle deceleration control device The node point density Dnode is calculated (step S21). Then, the vehicle deceleration control device corrects the target vehicle speed Vr _j based on the calculated node point density Dnode (step S22). Specifically, the vehicle deceleration control device generally decreases the offset value Kvr as the node point density Dnode increases (see FIG. 10).

FIG. 12 shows the relationship between the target vehicle speed Vr _j and the branch point flag flgb. As shown in the figure, (when the runway so that the more the vehicle travels is determined that becomes the branch path) branch point flag flgb is As the 1, correction is performed to increase the target vehicle speed Vr _j by the offset value Kvr. Then, the offset value Kvr is maintained for a predetermined time (A section shown in the figure), and then the offset value Kvr is decreased (B section shown in the figure). Here, in the second half of the section A shown in the figure, the target vehicle speed Vr _j corrected, although increased by the offset value Kvr fraction, since the target vehicle speed Vr _j before correction is reduced (the dotted line shown in FIG values ), Will decrease. By correcting the target vehicle speed Vr _{j so as} to increase in this way, the target deceleration Xgs _j (minimum target deceleration Xgsmin) increases, and it becomes difficult for the deceleration control to intervene. Further, even if deceleration control is intervened, the target deceleration Xgs _j (minimum target deceleration Xgsmin) increases, so that the target vehicle speed command value Vrr also increases, and the deceleration is normal (before correction). It becomes suppressed compared with.

FIG. 13 shows another example of the relationship between the target vehicle speed Vr _j and the branch point flag flgb. As shown in the figure, or to reduce the offset value Kvr, predetermined time for maintaining the value by or shorter (A section shown in the figure), the return to the target vehicle speed Vr _j to the value before correction It can also be made easier.
FIG. 14 shows a general relationship between the shape of the road 200 and node point information obtained from the navigation device 14. As shown in the figure, the node point information is dense on the curved road 200c. That is, the number of node points increases on the curved road 200c. On the other hand, the node point information is rough on the straight path 200a. That is, the number of node points is reduced on the straight path 200a. Normally, the number of node points remains small in the branch path 200b as well. In such a case, consider a case where the host vehicle 100 selects the branch road 200b as the travel path.

  In this case, as shown in FIG. 15, a node point near the branch point may be selected as a calculation target for calculating the turning radius. That is, the turning radius may be calculated from the coordinates of three consecutive node points according to the equation (2). However, in the vicinity of the branch point, the number of node points obtained from the navigation device 14 is small, and the calculated turning radius is also affected. That is, if three node points as shown in the figure are used, a turning radius that indicates a curved road is calculated even though the node is simply branched. And if deceleration control is operated based on the turning radius, it will decelerate more than necessary and will give the driver a feeling of strangeness.

In contrast, when the vehicle deceleration control device has a branch point on the travel path and the travel path on which the vehicle travels becomes a branch path, the offset of the node point density Dnode calculated at that time decreases. increase the value Kvr, I have a correction to increase the target vehicle speed Vr _j. As a result, the lower the node point density Dnode, the larger the minimum target deceleration Xgsmin and the slower the intervention timing of the deceleration control. That is, it is difficult to intervene in deceleration control. Furthermore, even if deceleration control is intervened, the minimum target deceleration Xgsmin increases as the node point density Dnode decreases, so the deceleration is also suppressed compared to the normal one. That is, as the control content of the deceleration control is corrected, the intervention timing of the deceleration control is delayed or the deceleration is reduced. Thus, the vehicle deceleration control device appropriately evaluates the shape of the branch road at the branch point, and operates the deceleration control in conformity with the road shape. As a result, the vehicle deceleration control device prevents the deceleration control performed on the curve from inadvertently operating at the branch point.

  In addition, as described with reference to FIG. 13, by reducing the offset value Kvr or shortening the predetermined time for maintaining the value (A section shown in FIG. 13), the branch path is controlled to decelerate. When it is determined that the vehicle is a necessary curved road (when it is highly likely that the road is a curved road), the deceleration control can be appropriately performed at the branch point that becomes the curved road.

The first embodiment can also be realized by the following configuration.
That is, in this first embodiment, and corrects the target vehicle speed Vr _j. On the other hand, the allowable lateral acceleration Yglimt can be corrected. That is, for example, as described above, the allowable lateral acceleration Yglimt is corrected by adding an offset value to the allowable lateral acceleration Yglimt. Also doing so, it is possible to obtain the same effect as obtained by correcting the target vehicle speed Vr _j.

In the first embodiment, the offset value Kvr is calculated based on the node point density Dnode. On the other hand, the offset value Kvr can also be calculated based on the average distance between the node points before and after the branch point. In this case, for example, an average distance between node points before and after the branch point (hereinafter simply referred to as an average distance between node points) Lnode is calculated by the following equation (15).
Lnode = L _k / K (15)
Here, L _k (k = p to q, p and q are integers) is a distance (a distance between the node points) from the node point N _p including the branch point to the node point N _q . K is the number of node points within the distance L _k .
Then, as shown in the following equation (16), an offset value Kvr is calculated using the average distance Lnode between the node points as a variable.
Kvr = f6 (Lnode) (16)

  FIG. 16 shows an example of the relationship between the average distance Lnode between node points and the offset value Kvr. As shown in the figure, the offset value Kvr is a constant small value in the region where the average distance Lnode between the node points is long. When the node-to-node average distance Lnode becomes longer than a certain value, the offset value Kvr increases as the node-to-node average distance Lnode increases. When the node-point average distance Lnode is further increased, the offset value Kvr becomes a constant large value regardless of the node-point average distance Lnode. In order to obtain such a relationship, an offset value Kvr is obtained based on the average distance Lnode between the node points (the above equation (16)). That is, as a general rule, the offset value Kvr is increased as the average distance Lnode between the node points becomes longer (as the number of node points increases).

In the first embodiment, a branch point is detected based on information obtained from the navigation device 14. On the other hand, a branch point can also be detected by other means. That is, for example, the front of the vehicle can be imaged by a camera, and a branch point can be detected based on the captured image.
In the first embodiment, the branch point is detected, and the deceleration control performed for the detected branch point is suppressed. On the other hand, it is also possible to detect the merging point and suppress the deceleration control performed for the detected merging point.
Moreover, in this 1st Embodiment, the control content of deceleration control is correct | amended on the requirement that the runway where the own vehicle will drive | work is a branch road. On the other hand, if the branch point can be detected, it is possible to correct the control content of the deceleration control without requiring that the traveling road on which the vehicle travels is a branch road.

  In the first embodiment, the predetermined time for maintaining the offset value Kvr is obtained based on the length of the curve section. On the other hand, the predetermined time can be obtained based on other values. For example, the predetermined time can be calculated based on the arrival time from the passage of the branch point to the curve, the turning radius of the curve, and the target vehicle speed at the time of passing the curve. For example, the shorter the arrival time, the shorter the predetermined time. Alternatively, the predetermined time is shortened as the turning radius of the curve becomes smaller. Alternatively, the predetermined time is calculated based on the difference between the target vehicle speed when passing through the branch point and the target vehicle speed of the curve ahead. For example, the predetermined time is shortened as the difference increases. Furthermore, a predetermined time can be obtained from a combination of values such as the arrival time and the value of the turning radius. For example, each predetermined time obtained from values such as the length of the curve section, the arrival time, and the turning radius is weighted to determine the final predetermined time.

  In the first embodiment, Δkvr1 for decreasing the offset value Kvr is a predetermined amount (fixed value). On the other hand, Δkvr1 can also be obtained based on other values. For example, Δkvr1 can be calculated on the basis of the length of the curve section, the time it takes to reach the curve after passing through the branch point, the turning radius of the curve, and the target vehicle speed when passing the curve. For example, Δkvr1 is increased as the arrival time becomes shorter. Alternatively, Δkvr1 is increased as the turning radius of the curve decreases. Alternatively, Δkvr1 is calculated based on the difference between the target vehicle speed when passing through the branch point and the target vehicle speed of the curve ahead. For example, Δkvr1 is increased as the difference increases. Furthermore, Δkvr1 can also be obtained from a combination of values such as values of the curve section length, arrival time, turning radius and the like. For example, each Δkvr1 obtained from values such as the arrival time and the turning radius is weighted to determine the final Δkvr1.

  In the first embodiment, the alarm operation start determination and the deceleration control operation start determination are performed based on the minimum target deceleration Xgsmin. On the other hand, it is also possible to make an alarm operation start determination or a deceleration control operation start determination based on other determination criteria. That is, for example, it is also possible to make a warning operation start determination or a deceleration control operation start determination using the target vehicle speed command value Vrr.

  FIG. 17 shows a process when the alarm activation start determination is performed using the target vehicle speed command value Vrr. As shown in the figure, the warning control unit 46 makes a warning activation start determination using the set vehicle speed Vset, the host vehicle speed V, and the target vehicle speed command value Vrr. Regarding the set vehicle speed Vset, the vehicle speed setting unit 47 outputs the set vehicle speed Vset to the alarm control unit 46 in accordance with the operation signal of the ACC switch 23. In this alarm activation start determination, for example, when the set vehicle speed Vset is equal to the host vehicle speed V (Vset = V), the target vehicle speed command value Vrr is less than the set vehicle speed Vset (own vehicle speed V). (Vrr <Vset), the alarm activation flag flg1 is set to 1 (flg1 = 1). Thereby, when the alarm activation flag flg1 becomes 1, the alarm is activated.

  FIG. 18 shows a process when the deceleration control operation start determination is performed using the target vehicle speed command value Vrr. As shown in the figure, the vehicle speed command value calculation unit 48 makes a warning activation start determination using the set vehicle speed Vset, the host vehicle speed V, and the target vehicle speed command value Vrr. Regarding the set vehicle speed Vset, the vehicle speed setting unit 47 outputs the set vehicle speed Vset to the vehicle speed command value calculation unit 48 in accordance with the operation signal of the ACC switch 23. In this deceleration control operation start determination, for example, when the set vehicle speed Vset and the host vehicle speed V are equal (Vset = V), the vehicle speed command value calculation unit 48 sets the target vehicle speed command value Vrr to the set vehicle speed Vset (host vehicle speed V). When it is less than (Vrr <Vset), the deceleration control operation flag flg2 is set to 1 (flg2 = 1). Thus, when the deceleration control operation flag flg2 becomes 1, the deceleration control is activated (braking fluid pressure rises).

  In the first embodiment, the navigation information processing unit 43 uses a plurality of node points used for creating map information in the navigation device, and calculates a turning radius calculating means for calculating the turning radius of the traveling road ahead of the vehicle. Is realized. Further, the target deceleration calculation unit 44 realizes target deceleration calculation means for calculating the target deceleration of the host vehicle based on the turning radius calculated by the turning radius calculation means. The target deceleration calculation unit 44, the target vehicle speed command value calculation unit 45, the alarm control unit 46, the vehicle speed command value calculation unit 48, the vehicle speed servo calculation unit 49, the torque distribution control calculation unit 50, the brake hydraulic pressure calculation unit 51, and the engine The torque calculation unit 52 realizes a deceleration control unit that performs deceleration control of the vehicle based on the target deceleration calculated by the target deceleration calculation unit. Further, the branch point determination unit 61 realizes a branch point detection unit that detects a branch point in front of the vehicle, and a branch road traveling determination unit that determines whether or not the traveling road on which the host vehicle travels is a branch road. Yes. Further, the target vehicle speed correction unit 62 calculates the density of the node points within a predetermined range of the branch road when the branch road travel determination unit determines that the travel road on which the host vehicle travels is a branch road. As the value becomes smaller, a correction unit that corrects the degree of suppression of the target deceleration calculated by the target deceleration calculation unit is realized.

In the first embodiment, the vehicle speed calculation unit 41, the target vehicle speed calculation unit 42, the target deceleration calculation unit 44, the target vehicle speed command value calculation unit 45, the alarm control unit 46, the vehicle speed command value calculation unit 48, the vehicle speed servo The computing unit 49, the torque distribution control computing unit 50, the brake fluid pressure computing unit 51, and the engine torque computing unit 52 are vehicle speed control means for controlling the deceleration of the host vehicle based on the turning radius calculated by the turning radius calculating means. Realized. Moreover, the branch point determination part 61 implement | achieves the branch junction detection means which detects the branch point or junction point ahead of a vehicle. Further, the target vehicle speed correction unit 62 corrects the control content of the deceleration control of the vehicle speed control means based on the branch point detected by the branch / merge point detection means or the number of node points within a predetermined range of the merge point. A correction means is realized.
Further, in the first embodiment, deceleration control at the branch point is performed based on the density of node points that exist within a predetermined range of the branch point in front of the vehicle and are used to create map information by the navigation device. A vehicle deceleration control method is realized.

(effect)
The effects of the first embodiment are as follows.
(1) The degree of suppression of deceleration control is increased as the node point density Dnode decreases, that is, as the number of node points decreases. Specifically, the degree of suppression of the target deceleration is increased. As a result, the deceleration control can be performed in conformity with the state of the curve at the branch point.
(2) The deceleration of the deceleration control is made smaller as the node point density Dnode becomes lower. As a result, the deceleration control can be performed in conformity with the state of the curve at the branch point.
(3) The lower the node point density Dnode, the slower the deceleration control intervention timing. As a result, the deceleration control can be performed in conformity with the state of the curve at the branch point.

(4) When the minimum target deceleration Xgsmin becomes less than the deceleration control operation determination threshold value Xgsth2, deceleration control is performed so as to realize the minimum target deceleration Xgsmin. As the target vehicle speed Vr _j increases, the minimum target deceleration Xgsmin increases (see equation (4) above), and therefore, in this process, the target vehicle speed Vr _j becomes less than a predetermined threshold value (or may be less). Sometimes, this is equivalent to performing deceleration control so that the target vehicle speed Vr _j is obtained. Then, in this embodiment, by correcting the target vehicle speed Vr _j at a large value by the offset value Kv, it is to increase the minimum target deceleration Xgsmin. Thereby, the intervention timing of the deceleration control is delayed, and the deceleration of the deceleration control after the intervention is reduced. Thus, only corrects the target vehicle speed Vr _j, slow intervention timing of the deceleration control, it is possible to reduce the deceleration of the deceleration control after the intervention.

(5) as the node point density Dnode decreases, and increase the target vehicle speed Vr _j. Accordingly, the intervention timing of the deceleration control can be delayed by adapting to the curve state at the branch point, and the deceleration of the deceleration control after the intervention can be reduced.
(6) is the corrected target vehicle speed Vr _j and maintained for a predetermined time. Thus, by setting the predetermined time according to the traveling situation or the like, the deceleration control at the branch point can be adapted to the traveling situation or the like.

(7) the curve of the section length, the time from the branch point to reach the curve, the curve of the turning radius, at least one of the difference between the target vehicle speed Vr _j calculated for the target vehicle speed Vr _j and curves calculated for the branch point The predetermined time is determined based on the above. Thereby, the deceleration control at the branch point can be adapted again to the situation of the curve to be controlled after passing through the branch point, and can be more appropriately connected to the next deceleration control.

(8) After a predetermined time has elapsed, the offset value Kvr is gradually decreased. Thus, after the predetermined time has elapsed, the corrected target vehicle speed Vr _j is gradually decreased to the target vehicle speed Vr _j before the correction (in other words, it is gradually accelerated). Thereby, the deceleration control at the branch point can be adapted to the deceleration control that is performed again on the curve to be controlled after passing through the branch point. That is, for example, the first deceleration control (deceleration control for the branch point) can be smoothly connected to the next deceleration control (deceleration control for the curve after the branch point) by suppressing the acceleration after the end.

(9) the curve of the section length, the time from the branch point to reach the curve, the curve of the turning radius, at least one of the difference between the target vehicle speed Vr _j calculated for the target vehicle speed Vr _j and curves calculated for the branch point based on, gradually decreasing the target vehicle speed Vr _j corrected to the target vehicle speed Vr _j before the correction. Thereby, the deceleration control at the branch point can be adapted again to the situation of the curve to be controlled after passing through the branch point, and can be more appropriately connected to the next deceleration control.
(10) The control content of the deceleration control is changed based on the average distance between the respective node points existing within the predetermined range. Thereby, the number of nodes within a predetermined range can be easily calculated, and the control content of the deceleration control can be corrected based on the calculated value.

(Second Embodiment)
(Constitution)
2nd Embodiment is a rear-wheel drive vehicle carrying the vehicle deceleration control apparatus which concerns on this invention. In the second embodiment, the processing content of step S22 in the first embodiment is changed. That is, the function f5 is a function that increases Vr _j , but the specific contents are different. Specifically, in the second embodiment, as shown in the following equation (17) is corrected by replacing the target vehicle speed Vr _j at a predetermined value (replacement value) Vr1.
Vr _j = Vr1 (17)
Predetermined value Vr1 is uncorrected target vehicle speed is (initial target vehicle speed) Vr _j or more. Specifically, as shown in the following equation (18), the predetermined value Vr1 is calculated using the node point density Dnode as a variable.
Vr1 = f7 (Dnode) (18)

  FIG. 19 shows an example of the relationship between the node point density Dnode and the predetermined value Vr1. As shown in the figure, in the region where the node point density Dnode is high, the predetermined value Vr1 is a constant large value. When the node point density Dnode becomes higher than a certain value, the predetermined value Vr1 becomes smaller as the node point density Dnode becomes higher. When the node point density Dnode is further increased, the predetermined value Vr1 becomes a constant small value regardless of the node point density Dnode. A predetermined value Vr1 is obtained on the basis of the node point density Dnode so as to satisfy such a relationship (formula (18)). That is, as a rule, the higher the node point density Dnode (the more node points), the smaller the predetermined value Vr1.

Then, the target vehicle speed correction unit 62 maintains the target vehicle speed Vr _j corrected by the equation (17) for a predetermined time and then decreases it. Specifically, the target vehicle speed correction unit 62 decreases the predetermined value Vr1 (target vehicle speed Vr _j ) by the following equation (19).
Vr1 = Vr1−Δkvr2 (19)
Here, Δkvr2 is a constant. According to the equation (19), the predetermined value Vr1 (target vehicle speed Vr _j ) gradually decreases according to the number of repetitions of the arithmetic processing in FIG. Also, the predetermined time is obtained according to the length of the curve section when the curve is detected before and after the branch point, as in the first embodiment (see FIG. 11).

(Operation and action)
Operation and action are as follows. Particularly in the second embodiment, the vehicle deceleration control device decreases the predetermined value Vr1 (target vehicle speed Vr _j ) as the node point density Dnode increases (see FIG. 19).
FIG. 20 shows the relationship between the target vehicle speed Vr _j and the branch point flag flgb. As shown in the figure, (when the runway further so that the vehicle is traveling is determined that becomes the branch path) the branch point flag flgb is 1, performs correction by replacing the target vehicle speed Vr _j at a predetermined value Vr1 . Then, the predetermined value Vr1 is maintained for a predetermined time (A section shown in the figure), and then the predetermined value Vr1 is decreased (B section shown in the figure). By correcting the target vehicle speed Vr _{j so as} to increase in this way, the target deceleration Xgs _j (minimum target deceleration Xgsmin) increases, and it becomes difficult for the deceleration control to intervene. Furthermore, even if deceleration control is intervened, the target vehicle speed command value Vrr is also increased because the target deceleration Xgs _j (minimum target deceleration Xgsmin) is increased, and the deceleration is compared with the normal one. It will be suppressed.
FIG. 21 shows another example of the relationship between the target vehicle speed Vr _j and the branch point flag flgb. As shown in the drawing, or by reducing the predetermined value Vr1, the predetermined time for maintaining the value by or shorter (A section shown in the figure), the return to the target vehicle speed Vr _j to the value before correction It can also be made easier.

As described above, when the vehicle deceleration control device has a branch point on the travel path and the travel path on which the host vehicle travels becomes a branch path, the lower the node point density Dnode calculated at that time, It is a correction to increase the target vehicle speed Vr _j. As a result, the lower the node point density Dnode, the larger the minimum target deceleration Xgsmin and the slower the intervention timing of the deceleration control. Furthermore, even if deceleration control is intervened, the minimum target deceleration Xgsmin increases as the node point density Dnode decreases, so the deceleration is also suppressed compared to the normal one. Thus, the vehicle deceleration control device appropriately evaluates the shape of the branch road at the branch point, and operates the deceleration control in conformity with the road shape. As a result, the vehicle deceleration control device prevents the deceleration control performed on the curve from inadvertently operating at the branch point.

Further, as described with reference to FIG. 21, the branch path is decelerated by decreasing the predetermined value Vr1 or shortening the predetermined time for maintaining the value (A section shown in FIG. 21). When it is determined that the vehicle is a necessary curved road (when it is highly likely that the road is a curved road), the deceleration control can be appropriately performed at the branch point that becomes the curved road.
The second embodiment can also be realized by the following configuration.
That is, in the second embodiment, the predetermined value Vr1 is calculated based on the node point density Dnode. On the other hand, the predetermined value Vr1 can also be calculated based on the average distance between the node points before and after the branch point. In this case, the predetermined value Vr1 is calculated based on the average distance Lnode between the node points calculated by the equation (15).

  FIG. 22 shows an example of the relationship between the node-point average distance Lnode and the predetermined value Vr1. As shown in the figure, in a region where the average distance Lnode between nodes is long, the predetermined value Vr1 is a constant small value. Then, when the node-to-node average distance Lnode becomes longer than a certain value, the predetermined value Vr1 increases as the node-to-node average distance Lnode increases. When the node-point average distance Lnode is further increased, the predetermined value Vr1 is a constant large value regardless of the node-point average distance Lnode. A predetermined value Vr1 is obtained based on the average distance Lnode between the node points so as to have such a relationship. That is, as a general rule, the predetermined value Vr1 is increased as the average distance Lnode between the node points becomes longer (as the number of node points increases).

In the second embodiment, the predetermined time for maintaining the predetermined value Vr1 (corrected target vehicle speed Vr _j ) is obtained based on the length of the curve section. On the other hand, the predetermined time can be obtained based on other values. For example, as in the case of the first embodiment, the predetermined time is calculated based on the arrival time from the passage of the branch point to the curve, the turning radius of the curve, and the target vehicle speed at the time of passing the curve. You can also. For example, the shorter the arrival time, the shorter the predetermined time. Alternatively, the predetermined time is reduced as the turning radius of the curve decreases. Alternatively, the predetermined time is calculated based on the difference between the target vehicle speed when passing through the branch point and the target vehicle speed of the curve ahead. For example, the predetermined time is shortened as the difference increases.

In the second embodiment, Δkvr2 for reducing the predetermined value Vr1 (corrected target vehicle speed Vr _j ) is a predetermined amount (fixed value). On the other hand, Δkvr2 can also be obtained based on other values. For example, as in the case of the first embodiment, Δkvr2 based on the length of the curve section, the time it takes to reach the curve after passing through the branch point, the turning radius of the curve, and the target vehicle speed when passing the curve Can also be calculated. For example, Δkvr2 is increased as the arrival time is shortened. Alternatively, Δkvr2 is increased as the turning radius of the curve decreases. Alternatively, Δkvr2 is calculated based on the difference between the target vehicle speed when passing through the branch point and the target vehicle speed of the curve ahead. For example, Δkvr2 is increased as the difference increases.

(effect)
The effects of the second embodiment are as follows.
(1) When the minimum target deceleration Xgsmin becomes less than the deceleration control operation determination threshold value Xgsth2, deceleration control is performed so as to realize the minimum target deceleration Xgsmin. As the target vehicle speed Vr _j increases, the minimum target deceleration Xgsmin increases (see equation (4) above), and therefore, in this process, the target vehicle speed Vr _j becomes less than a predetermined threshold value (or may be less). Sometimes, it is equivalent to performing deceleration control so as to achieve the target vehicle speed. Then, in the embodiment, by replacing the target vehicle speed Vr _j at a predetermined value Vr1, it is corrected to a larger value, and increase the minimum target deceleration Xgsmin. Thereby, the intervention timing of the deceleration control is delayed, and the deceleration of the deceleration control after the intervention is reduced. Thus, only corrects the target vehicle speed Vr _j, slow intervention timing of the deceleration control, it is possible to reduce the deceleration of the deceleration control after the intervention.
(2) a target vehicle speed Vr _j replaced by a predetermined value Vr1, is corrected to a larger value. Thus, regardless of the pre-correction target vehicle speed Vr _j, the target vehicle speed Vr _j corrected can be set to a desired value.

(Third embodiment)
(Constitution)
The third embodiment is a rear wheel drive vehicle equipped with the vehicle deceleration control device according to the present invention. The configuration of the vehicle of the third embodiment is the configuration shown in FIG. 1 as in the case of the first embodiment. FIG. 23 shows a processing procedure in the third embodiment. As shown in the figure, in the third embodiment, the basic processing is the same as the processing shown in FIG. 3 as in the case of the first embodiment. However, in the third embodiment, the process of step S31 is provided between the process of step S1 and the process of step S2. Furthermore, in 3rd Embodiment, the calculation method of the turning radius of said step S3 is changed in step S32. The braking / driving force control unit 8 includes a branch point determination unit 61 as shown in FIG. 24 in order to realize these processes. Note that the branch point determination unit 61 may be provided as a configuration in the navigation information processing unit 43.

Here, in the processing shown in FIG. 23, the processing given the same reference numeral (step number) as that given to the arithmetic processing shown in FIG. This is the same as the operation processing of No. 3.
In step S31, the branch point determination unit 61 determines a branch point in the same manner as in the first embodiment (see step S21). That is, the branch point determination unit 61 calculates the node point density Dnode before and after the branch point when there is a branch point on the forward travel path and the travel path on which the host vehicle travels becomes a branch path.

  In step S32, the navigation information processing unit 43 changes the filter constant when calculating the turning radius, and calculates the turning radius of each node point. Specifically, the navigation information processing unit 43 determines in step S31 that there is a branch point on the travel path of the host vehicle (flgb = 1), and the travel path of the host vehicle is also set in the branch direction. , Change the filter constant. The predetermined distance is, for example, 50 m.

Here, the filter constant is changed based on the node point density Dnode calculated in step S31 (see equation (10)). Specifically, the time constant of the filter is increased as the node point density Dnode decreases. For example, when the node point density Dnode is less than or equal to a predetermined value, the filter constant is changed (the time constant of the filter is increased). Such a change is intended to prevent detection of curves (curves based on node points before and after the branch point). As a result, for example, the turning radius R _j calculated by the equation (2) is larger than the normally calculated value (the value before the change). On the other hand, when the node point density Dnode is larger than a predetermined value, the filter constant is returned to the base (the filter time constant is reduced). This change is for detecting a curve (a curve based on node points before and after the branch point).

(Operation and action)
Operation and action are as follows. In particular, in the third embodiment, the vehicle deceleration control device performs the processing shown in FIG. 23, when the branch point is on the front travel path and the travel path on which the host vehicle travels becomes the branch path. The node point density Dnode before and after the branch point is calculated (step S31). Then, the vehicle deceleration control device changes the filter constant based on the calculated node point density Dnode (step S32). Further, the vehicle deceleration control device calculates the turning radius R _j under the changed filter constant. Then, the vehicle deceleration control device, in the subsequent processing, performs processing by using the turning radius R _j that the calculated. That is, for example, the vehicle deceleration control device calculates the target vehicle speed Vr _j using the turning radius R _j (see step S4, equation (3) above).

FIG. 25 shows an image of the turning radius R _j calculated according to the setting of the filter constant. As shown in the figure, when the filter constant is set in a direction in which no curve is detected (when the time constant is increased), the turning radius R _j is increased (image like the dotted line shown in the figure). On the other hand, when the filter constant is set in the direction of detecting the curve (decreasing the time constant or returning the time constant), the turning radius R _j decreases (image like the solid line shown in the figure).

As described above, when the vehicle deceleration control device has a branch point on the travel path and the travel path on which the host vehicle travels becomes a branch path, the lower the node point density Dnode calculated at that time, The filter constant is set in the direction not detecting the curve. Thus, as the node point density Dnode decreases, since the turning radius R _j is increased, the target vehicle speed Vr _j becomes larger (the (3) reference expression). As a result, as in the first and second embodiments, as the node point density Dnode decreases, the minimum target deceleration Xgsmin increases and the intervention timing of the deceleration control is delayed. Furthermore, even if deceleration control is intervened, the minimum target deceleration Xgsmin increases as the node point density Dnode decreases, so the deceleration is also suppressed compared to the normal one. Thus, the vehicle deceleration control device appropriately evaluates the shape of the branch road at the branch point, and operates the deceleration control in conformity with the road shape. As a result, the vehicle deceleration control device prevents the deceleration control performed on the curve from inadvertently operating at the branch point.

The third embodiment can also be realized by the following configuration.
That is, in the third embodiment, the filter constant is changed based on the node point density Dnode. On the other hand, the filter constant can also be changed based on the average distance Lnode between the node points (see the equation (15)). In this case, the time constant of the filter is increased as the average distance Lnode between the node points becomes longer. For example, when the average distance Lnode between the node points is a predetermined value (for example, 30 m) or more, the filter constant is changed (the time constant of the filter is increased). As a result, for example, the turning radius R _j calculated by the equation (2) is larger than the value calculated normally. On the other hand, when the average distance Lnode between the node points is less than the predetermined value, the filter constant is returned to the base (the time constant of the filter is reduced).

(effect)
The effects of the third embodiment are as follows.
(1) The calculation processing content by the navigation information processing unit 43 is changed to correct the calculated turning radius R _j and the target vehicle speed Vr _j . Accordingly, the target vehicle speed Vr _j easily corrected, can be easily corrected control contents of the deceleration control.
(2) The filter constant is changed to correct the calculated turning radius R _j . Thus, the corrected turning radius R _j can be output as a continuous value, and the deceleration control after correcting the turning radius R _j can be performed while suppressing fluctuations.

(Fourth embodiment)
(Constitution)
The fourth embodiment is a rear wheel drive vehicle equipped with the vehicle deceleration control device according to the present invention. In the fourth embodiment, the processing content of step S32 in the third embodiment is changed. That is, in the fourth embodiment, the method for calculating the turning radius is changed by a method different from that of the third embodiment.
That is, in step S32 in the fourth embodiment, the navigation information processing unit 43 determines that there is a branch point on the front travel path and that the travel path on which the vehicle will travel is a branch path (the step). S31), node points existing within a predetermined distance before and after the branch point are excluded. For example, as shown in FIG. 26, the node point (one point) including the node point indicating the branch point is excluded as the node point within the predetermined distance L. The predetermined distance is, for example, 50 m. At this time, as shown in the figure, the node points to be excluded can be determined based on the angle (node point angle) θ formed by the branch path with the branch point as the center. For example, when the node point angle θ is greater than or equal to a predetermined value, the node point corresponding to the branch point can be excluded. The predetermined value is 60 °, for example. Then, the navigation information processing unit 43 eliminates the node points in this way, and calculates the turning radius R _j based on the remaining node points (see the above formula (2)).

(Operation and action)
Operation and action are as follows. In particular, in the fourth embodiment, the vehicle deceleration control device has a branch point on the forward travel path, and when the travel path on which the vehicle travels becomes a branch path (step S31), before and after the branch point. Node points existing within a predetermined distance are excluded (step S32). Further, the vehicle deceleration control device calculates a turning radius R _j based on the remaining node points. Then, the vehicle deceleration control device, in the subsequent processing, performs processing by using the turning radius R _j that the calculated. Thus, for example, the vehicle deceleration control system, turning radius with R _j and (turning radius R _j which is calculated by eliminating the appropriate node point), calculates the target vehicle speed Vr _j (step S4, the equation (3) reference).

As described above, the vehicle deceleration control apparatus increases the turning radius R _j calculated at the branch point and increases the target vehicle speed Vr _j by excluding the node point (see the equation (3) above). ). As a result, as in the first to third embodiments, the minimum target deceleration Xgsmin is increased and the intervention timing of the deceleration control is delayed. Further, even if deceleration control is intervened, the minimum target deceleration Xgsmin is increased, so that the deceleration is suppressed as compared with the normal one. Thus, the vehicle deceleration control device appropriately evaluates the shape of the branch road at the branch point, and operates the deceleration control in conformity with the road shape. As a result, the vehicle deceleration control device prevents the deceleration control performed on the curve from inadvertently operating at the branch point.
Further, when the node point angle θ is equal to or larger than a predetermined value, the node point of the branch point is excluded. As a result, it is possible to prevent unnecessary removal of node points, and to appropriately perform deceleration control.

The fourth embodiment can also be realized by the following configuration.
In the fourth embodiment, when there is a branch point on the front travel path and the travel path on which the host vehicle travels becomes a branch path, and further when the node point angle θ is greater than or equal to a predetermined value, Eliminate points. On the other hand, the node points can be eliminated based on the node point density Dnode (see the above equation (10)) and the average distance Lnode between the node points (see the above equation (15)). In this case, for example, when the average distance Lnode between the node points is equal to or smaller than a predetermined value, or when the average distance Lnode between the node points is equal to or larger than the predetermined value, the node points are excluded. Furthermore, the number of node points to be excluded can be determined according to the node point angle, the node point density Dnode, and the average distance Lnode between the node points. For example, as the node point angle increases, the number of node points to be excluded is increased. Alternatively, the higher the node point density Dnode, the larger the number of node points to be excluded. Alternatively, the number of node points to be eliminated is increased as the average distance Lnode between the node points is increased.

(effect)
The effects of the fourth embodiment are as follows.
(1) The calculation processing content by the navigation information processing unit 43 is changed to correct the calculated turning radius R _j and the target vehicle speed Vr _j . Accordingly, the target vehicle speed Vr _j easily corrected, can be easily corrected control contents of the deceleration control.
(2) The turning radius R _j is corrected by excluding the node points used for calculating the turning radius R _j at the node points near the node point of the branch point. Thus, the turning radius R _j can be corrected by a simple process such as removing node points.

(Fifth embodiment)
(Constitution)
5th Embodiment is a rear-wheel drive vehicle carrying the vehicle deceleration control apparatus which concerns on this invention. The configuration of the vehicle according to the fifth embodiment is the same as that shown in FIG. 1 as in the first embodiment. In the fifth embodiment, the same processing as in FIG. 3 described in the first embodiment is performed. However, in the fifth embodiment, traveling control is performed according to the state of the front road after passing through the branch point. Therefore, in the fifth embodiment, an acceleration suppression processing unit 71 is provided as shown in FIG.

  FIG. 28 shows a processing procedure of the acceleration suppression processing unit 71. As shown in the figure, first, in step S41, the acceleration suppression processing unit 71 determines whether or not the deceleration control is activated at the branch point (whether or not it is activated). That is, the acceleration suppression processing unit 71 determines whether or not the deceleration control is activated by the processing of FIG. If the acceleration suppression processing unit 71 operates the deceleration control at the branch point, the process proceeds to step S42. If the acceleration suppression processing unit 71 is not operating the deceleration control at the branch point, the processing shown in FIG. 28 is terminated.

In step S42, the acceleration suppression processing unit 71 determines whether or not a branch point has been passed. If the acceleration suppression processing unit 71 passes the branch point, the process proceeds to step S43. If the acceleration suppression processing unit 71 does not pass through the branch point, the processing shown in FIG. 28 ends.
In step S43, the acceleration suppression processing unit 71 determines whether to operate the deceleration control for the previous node point. That is, the acceleration suppression processing unit 71 determines whether to operate the deceleration control by the processing shown in FIG. The acceleration suppression processing unit 71 proceeds to step S44 when operating the deceleration control for the previous node point. Further, the acceleration suppression processing unit 71 ends the processing shown in FIG. 28 when the deceleration control is not activated for the previous node point.

  In step S44, the acceleration suppression processing unit 71 performs a process of suppressing acceleration. Specifically, the acceleration suppression processing unit 71 suppresses an increase in acceleration or prohibits acceleration itself. According to the processing of step S41 and step S42, the case of proceeding to step S44 is a case where deceleration control has already been activated at a branch point and the branch point has been passed. For this reason, in step S44, the acceleration suppression processing unit 71 suppresses acceleration related to the end of the deceleration control operated at the branch point after passing through the branch point. Moreover, the acceleration suppression processing part 71 suppresses the acceleration only for time. Here, the time (predetermined time) is, for example, 3 seconds. Also, a predetermined time can be set based on the arrival time. The arrival time is the time from reaching the branch point until reaching the curve (previous node point) to be controlled.

  FIG. 29 shows the relationship between the arrival time and the predetermined time. As shown in the figure, in a region where the arrival time is short, the holding time is set to a constant large value. And when arrival time becomes larger than a certain value, predetermined time is shortened, so that arrival time becomes long. When the arrival time becomes longer, the predetermined time is set to a constant small value regardless of the arrival time. That is, as a general rule, the longer the arrival time, the shorter the predetermined time.

(Operation and action)
Operation and action are as follows.
The vehicle deceleration control device operates deceleration control at a branch point, passes through the branch point, and further performs processing for suppressing acceleration when the deceleration control is operated for the previous node point ( Steps S41 to S44). That is, the vehicle deceleration control device determines that the vehicle is accelerating (decreases deceleration) by passing through the branch point, and further, the vehicle front curve is set as the control target of the deceleration control. Then, when it is determined that the deceleration control is activated again, processing for suppressing the acceleration is performed. Specifically, the vehicle deceleration control device suppresses acceleration for a limited time.

FIG. 30 shows a change in the minimum target deceleration Xgsmin before and after the branch point. As shown in the figure, the minimum target deceleration Xgsmin becomes smaller corresponding to the branch point. That is, as the turning radius R calculated for the branch point becomes smaller, the minimum target deceleration Xgsmin becomes smaller. Thereby, when the minimum target deceleration Xgsmin becomes small to some extent (Xgsmin <Xgsth2), the deceleration control is activated. At this time, as described above in the first to fourth embodiments, by correcting such a target vehicle speed Vr _j in accordance with the node point density DNODEs, it can suppress the operation of the deceleration control at the branch point. After that, when a curve to be controlled is detected again when passing through a branch point and accelerating by ending deceleration control, the acceleration is suppressed. By doing so, it is possible to prevent the acceleration / deceleration from occurring in the vehicle before and after passing through the branch point. Thereby, it is possible to prevent the deceleration control from causing the driver to feel uncomfortable.

The fifth embodiment can also be realized by the following configuration.
That is, in the fifth embodiment, a predetermined time for suppressing acceleration is obtained based on the arrival time. On the other hand, a predetermined time can be obtained based on another index. For example, the predetermined time can be determined based on the distance from the branch point to the next curve, or the difference between the set vehicle speed of the host vehicle and the target vehicle speed with respect to the curve ahead of the vehicle.
In the fifth embodiment, a predetermined time is determined based on the arrival time, and acceleration is suppressed at the predetermined time. On the other hand, as a process for suppressing the acceleration, the acceleration itself can be suppressed based on the distance from the branch point to the next curve, the arrival time, and the like. For example, the acceleration is increased as the distance becomes longer or the arrival time becomes longer.

In the fifth embodiment, the navigation device 14 implements a forward travel path detection unit that detects a curve ahead of the vehicle. The vehicle speed calculation unit 41, the target vehicle speed calculation unit 42, the navigation information processing unit 43, the target deceleration calculation unit 44, the target vehicle speed command value calculation unit 45, the alarm control unit 46, the vehicle speed command value calculation unit 48, and the vehicle speed servo calculation unit. 49, the torque distribution control calculation unit 50, the brake hydraulic pressure calculation unit 51, and the engine torque calculation unit 52 realize a deceleration control unit that controls the vehicle to decelerate with respect to a curve ahead of the vehicle detected by the front traveling path detection unit. doing. The acceleration suppression processing unit 71 detects a branch point or junction point in front of the vehicle, and the deceleration control target after passing through the branch point or junction point detected by the branch junction point detector. When there is such a curve, an acceleration suppression means that suppresses acceleration related to the end of the operation of the deceleration control performed at the branch point or merging point is realized.
Further, in the fifth embodiment, there is provided a vehicle deceleration control method for suppressing acceleration related to the end of the deceleration control operation performed at the branch point when there is a curve subject to deceleration control after passing through the branch point. Realized.

(effect)
The effects of the fifth embodiment are as follows.
(1) When there is a curve to be subjected to deceleration control after passing through the branch point, acceleration related to the end of the deceleration control operation performed at the branch point is suppressed. As a result, it is possible to prevent the vehicle from being accelerated more than necessary due to the end of the previous deceleration control operation, even though the vehicle is decelerated again in the subsequent deceleration control. That is, it is possible to prevent the vehicle speed from changing unnecessarily.
(2) Based on the distance from the branch point to the next curve, the acceleration associated with the termination of the deceleration control operation performed on the branch point is suppressed. Specifically, acceleration is suppressed based on the arrival time. Thereby, according to the relationship between a branch point and the next curve, the acceleration by the completion | finish of the operation | movement of the previous deceleration control can be suppressed appropriately.

1 is a diagram illustrating a configuration of a vehicle according to a first embodiment of the present invention. It is a block diagram which shows the structural example of a braking / driving force control unit. It is a flowchart which shows the process sequence of the arithmetic processing performed with a braking / driving force control unit. It is the figure used for description which calculates turning radius _Rj based on three consecutive node points _Nj-1 , _Nj , and _{Nj + 1} . It is a figure which shows turning radius _Rj (● mark in a figure) of each node point _Nj (node point number). It is a characteristic view which shows the relationship between the minimum target deceleration Xgsmin and the warning operation flag flg1. FIG. 5 is a characteristic diagram showing a relationship between a minimum target deceleration Xgsmin and a deceleration control operation flag flg2. It is a flowchart which shows the process sequence of the specific arithmetic processing performed with a braking / driving force control unit. It is a block diagram which shows the structural example of the braking / driving force control unit for implement | achieving the process of FIG. It is a characteristic view which shows the relationship between node point density Dnode and offset value Kvr. It is a characteristic view which shows the relationship between the length of a curve area, and predetermined time. It is a diagram used for explaining a target vehicle speed Vr _j corrected by the offset value Kvr. It is a diagram used for explaining a target vehicle speed Vr _j corrected by small offset value Kvr. It is the figure used for description of the relationship between a road shape and the node point information obtained from a navigation apparatus. It is a figure used for explanation when a node point near a branch point is selected as a calculation target for calculating a turning radius. It is a characteristic view which shows the relationship between the average distance Lnode between node points, and the offset value Kvr. It is the figure used for description of the process at the time of making a warning action start determination using the target vehicle speed command value Vrr. It is the figure used for description of the process at the time of performing the deceleration control action start judgment using the target vehicle speed command value Vrr. FIG. 10 is a characteristic diagram showing a relationship between a node point density Dnode and a predetermined value Vr1 in the second embodiment. It is a diagram used for explaining a target vehicle speed Vr _j corrected by replacing the predetermined value Vr1. It is a diagram used for explaining a small predetermined value the target vehicle speed Vr _j is replaced with Vr1. It is a characteristic view which shows the relationship between the average distance Lnode between node points, and predetermined value Vr1. It is a flowchart which shows the process sequence of the arithmetic processing performed in the braking / driving force control unit in 3rd Embodiment. It is a block diagram which shows the structural example of the braking / driving force control unit for implement | achieving the process of FIG. Is a diagram showing an image of turning radius R _j is calculated in accordance with the setting of the filter constant. It is the figure used for description which excludes a node point in 4th Embodiment. It is a block diagram which shows the structural example of the braking / driving force control unit in 5th Embodiment. It is a flowchart which shows the process sequence of the acceleration suppression process part of a braking / driving force control unit. It is a characteristic view which shows the relationship between arrival time and the predetermined time which suppresses acceleration. It is the figure used for description of the change of the minimum target deceleration Xgsmin before and after a branch point.

Explanation of symbols

  8 Braking / driving force control unit, 14 navigation device, 41 vehicle speed calculation unit, 42 target vehicle speed calculation unit, 43 navigation information processing unit, 44 target deceleration calculation unit, 45 target vehicle speed command value calculation unit, 46 alarm control unit, 47 vehicle speed Setting unit, 48 Vehicle speed command value calculation unit, 49 Vehicle speed servo calculation unit, 50 Torque distribution control calculation unit, 51 Brake fluid pressure calculation unit, 52 Engine torque calculation unit, 61 Branch point determination unit, 62 Target vehicle speed correction unit, 71 Acceleration Suppression processing unit

Claims (13)

A turning radius calculating means for calculating a turning radius of a traveling road ahead of the vehicle using a plurality of node points used for creating map information in the navigation device;
Target deceleration calculation means for calculating a target deceleration of the host vehicle based on the turning radius calculated by the turning radius calculation means;
Based on the target deceleration calculated by the target deceleration calculation means, deceleration control means for controlling the deceleration of the host vehicle;
In a vehicle deceleration control device comprising:
A branch point detecting means for detecting a branch point ahead of the vehicle;
A branch road travel judging means for judging whether or not the travel road on which the host vehicle is traveling is a branch road;
When the branch road travel judging means judges that the travel road on which the host vehicle travels is a branch road, the density of the node points within a predetermined range of the branch road is calculated, and the target decrease decreases as the value decreases. Correction means for greatly correcting the degree of suppression of the target deceleration calculated by the speed calculation means;
Target vehicle speed calculating means for calculating a target vehicle speed based on the turning radius calculated by the turning radius calculating means;
The deceleration calculation means performs the deceleration control based on the target deceleration obtained based on the target vehicle speed when the target vehicle speed calculated by the target vehicle speed calculation means is less than a predetermined threshold value. Start,
The correction means corrects the target vehicle speed calculated by the target vehicle speed means to a large value, maintains the corrected target vehicle speed for a predetermined time, and further controls the deceleration control beyond the branch point when viewed from the vehicle. When there is a target curve, the length of the section of the curve, the time to reach the curve from the branch point, the turning radius of the curve, the target vehicle speed calculated for the branch point, and the curve The vehicle deceleration control device characterized in that the predetermined time is determined based on at least one of the differences from the target vehicle speed . Based on the turning radius of the front of the vehicle traveling road that is obtained from the information of the navigation device, while calculating a target deceleration of the vehicle, on the basis of the target deceleration and the calculated deceleration control the vehicle, vehicle In the vehicle deceleration control device configured to correct the target deceleration when detecting a forward branch point and determining that the traveling road on which the host vehicle is traveling is a branch road ,
A target vehicle speed is calculated based on the turning radius, and when the target vehicle speed falls below a predetermined threshold, the deceleration control is started based on the target deceleration obtained based on the target vehicle speed. In addition, the target vehicle speed calculated by the target vehicle speed means is corrected to a large value, the corrected target vehicle speed is maintained for a predetermined time, and further, the object of the deceleration control is further beyond the branch point when viewed from the vehicle. When there is a curve, the length of the section of the curve, the time to reach the curve from the branch point, the turning radius of the curve, the target vehicle speed calculated for the branch point, and the target vehicle speed calculated for the curve The vehicle deceleration control device is characterized in that the predetermined time is determined on the basis of at least one of the differences. A turning radius calculating means for calculating a turning radius of a traveling road ahead of the vehicle using a plurality of node points used for creating map information in the navigation device;
Target deceleration calculation means for calculating a target deceleration of the host vehicle based on the turning radius calculated by the turning radius calculation means;
Based on the target deceleration calculated by the target deceleration calculation means, deceleration control means for controlling the deceleration of the host vehicle;
In a vehicle deceleration control device comprising:
A branch point detecting means for detecting a branch point ahead of the vehicle;
A branch road travel judging means for judging whether or not the travel road on which the host vehicle is traveling is a branch road;
When the branch road travel judging means judges that the travel road on which the host vehicle travels is a branch road, the density of the node points within a predetermined range of the branch road is calculated, and the target decrease decreases as the value decreases. Correction means for greatly correcting the degree of suppression of the target deceleration calculated by the speed calculation means;
Target vehicle speed calculating means for calculating a target vehicle speed based on the turning radius calculated by the turning radius calculating means;
The deceleration calculation means performs the deceleration control based on the target deceleration obtained based on the target vehicle speed when the target vehicle speed calculated by the target vehicle speed calculation means is less than a predetermined threshold value. Start,
The correction means corrects the target vehicle speed calculated by the target vehicle speed means to a large value, and maintains the corrected target vehicle speed for a predetermined time,
When there is a curve that is subject to deceleration control beyond the branch point when viewed from the vehicle, the correction means is configured such that the length of the section of the curve, the curve from the branch point after the predetermined time has elapsed. The corrected target vehicle speed is calculated based on at least one of the time until the vehicle reaches, the turning radius of the curve, the difference between the target vehicle speed calculated for the branch point and the target vehicle speed calculated for the curve. A deceleration control device for a vehicle, characterized by gradually reducing the vehicle speed to a target vehicle speed . Based on the turning radius of the front of the vehicle traveling road that is obtained from the information of the navigation device, while calculating a target deceleration of the vehicle, on the basis of the target deceleration and the calculated deceleration control the vehicle, vehicle In the vehicle deceleration control device configured to correct the target deceleration when detecting a forward branch point and determining that the traveling road on which the host vehicle is traveling is a branch road ,
A target vehicle speed is calculated based on the turning radius, and when the target vehicle speed falls below a predetermined threshold, the deceleration control is started based on the target deceleration obtained based on the target vehicle speed. In addition, the target vehicle speed calculated by the target vehicle speed means is corrected to a large value, the corrected target vehicle speed is maintained for a predetermined time, and further, the object of the deceleration control is further beyond the branch point when viewed from the vehicle. Is present, the length of the curve section after the predetermined time, the time to reach the curve from the branch point, the turning radius of the curve, the target vehicle speed calculated for the branch point, and the A vehicle characterized in that the corrected target vehicle speed is gradually reduced to the target vehicle speed before the correction based on at least one of the differences from the target vehicle speed calculated for the curve. Use deceleration control device. Wherein the correction means, as the density of the node point is lowered, the vehicle deceleration control device according to claim 1 or 3, characterized in that to reduce the target deceleration. 6. The vehicle deceleration control device according to claim 1 , wherein the correction unit delays the intervention timing of the deceleration control as the density of the node points decreases. 7. The vehicle deceleration control device according to claim 1 , 3, 5 or 6 , wherein the correction means increases the target vehicle speed as the density of the node points decreases. The said correction | amendment means reduces the said corrected target vehicle speed gradually to the target vehicle speed before this correction | amendment after progress of the said predetermined time , The any one of Claim 1, 3, 5-7 characterized by the above-mentioned. Vehicle deceleration control device. The correction means corrects the calculation processing content by the turning radius calculation means and corrects the turning radius to be calculated, thereby greatly correcting the degree of suppression of the target deceleration calculated by the target deceleration calculation means. The vehicle deceleration control device according to any one of claims 1, 3 , and 5 to 8 . Said correction means, said pivoting by correcting the filter constant of the radius calculation means, according to claim, characterized in that to increase correct the degree of suppression of target deceleration the target deceleration calculating means is calculated 1,3,5 The vehicle deceleration control device according to any one of? 9 . The correction means calculates the target deceleration by excluding a node point near the node point of the branch point detected by the branch / merging point detection means and a node point used by the turning radius calculation means to calculate the turning radius. The vehicle deceleration control device according to any one of claims 1, 3, 5 and 10, wherein the degree of suppression of the target deceleration calculated by the means is largely corrected. The correction means largely corrects the degree of suppression of the target deceleration calculated by the target deceleration calculation means based on an average distance between the respective node points existing within a predetermined range . vehicle deceleration control device according to any one of 3,5～11. Wherein when subject to curve the deceleration control after passing the branch point is present, according to claim 1, characterized in that it comprises a suppressing acceleration suppression means an acceleration of the working end of the deceleration control implemented in the branch point deceleration control apparatus for a vehicle according to any one of 3,5～12.

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