JPH11240434A - Vehicle movement control unit - Google Patents

Abstract

PROBLEM TO BE SOLVED: To enable starting movement control at an appropriate timing on future vehicle behavior when the vehicle is driving for a curve ahead. SOLUTION: A yaw rate response time calculation part 11 obtains an estimated value of road friction coefficient by estimating cornering power of wheels based on vehicle speed, steering angle, and yawing velocity, and then calculates yaw rate response time. A curve shape detection part 12 detects a curve ahead on a driving road based on information from a navigation unit 7 and a road shape detection unit 8, to calculate the distance from the vehicle to the curve ahead. A control start determination/control part 13 determines a timing for movement control start based on the vehicle speed, the yaw rate response time, and the distance to the curve ahead. At the timing for movement control start, a movement control start signal is output either to a braking force control unit 9 or an alarm unit 10.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a vehicle motion control device capable of controlling the motion of a vehicle at an appropriate timing.

[0002]

2. Description of the Related Art In recent years, vehicle behavior is detected based on the traveling environment and traveling state of the vehicle, and control such as braking force control and steering control is performed on the detected vehicle behavior, and an alarm is issued to a driver. 2. Description of the Related Art Various technologies have been developed for a vehicle motion control device that maintains vehicle safety by promoting vehicle behavior control such as a predetermined brake operation and steering operation.

For example, Japanese Patent Application Laid-Open No. 2-70561 discloses a method in which a target yaw rate is compared with an actual yaw rate (actual yaw rate) to determine whether the motion state of the vehicle is understeer or oversteer with respect to the target yaw rate. In addition, there is disclosed a technique in which a braking force is applied to an inner wheel in the case of an understeer tendency to make a correction, and in a case of an oversteer tendency, a braking force is applied to an outer wheel to make a correction, thereby improving stability during curve running.

[0004]

However, the control according to the prior art is a control which detects a current vehicle behavior based on an actual yaw rate, a steering wheel angle, and the like, and performs the detected current vehicle behavior. However, it is impossible to control future vehicle behavior expected during traveling, and there is a limit to improving safety.

On the other hand, by obtaining road information ahead of the traveling road based on navigation information, image information, and the like, future vehicle behavior at a forward curve or the like is detected, and the vehicle behavior at the detected forward curve or the like is detected. Techniques for improving stability during traveling by issuing an alarm or performing braking force control are being developed. However, in this technology, since the response time due to, for example, a delay in the response of the vehicle depending on the road surface condition is not taken into consideration, it is difficult to control the motion of the vehicle at an appropriate timing. There is a limit.

SUMMARY OF THE INVENTION The present invention has been made in view of the above circumstances, and provides a vehicle motion control device capable of starting motion control at an appropriate timing with respect to future vehicle behavior during forward curve running. With the goal.

[0007]

According to a first aspect of the present invention, there is provided a vehicle motion control apparatus according to the present invention.
In a vehicle motion control device that detects a traveling state of a vehicle and performs at least one of vehicle behavior control and alarm control in accordance with the detected traveling state to control the motion of the vehicle, a road surface friction coefficient based on the traveling state A yaw rate response time calculating means for calculating an estimated value, calculating a time until the yaw rate of the vehicle responds when the vehicle is steered based on the estimated value of the road surface friction coefficient and the vehicle speed, and detecting a curve ahead of the road. A curve shape detecting means for calculating a distance from the vehicle to the front curve, and the yaw rate response time calculated by the yaw rate response time calculating means and the distance to the front curve calculated by the curve shape detecting means. Control start determining / control means for determining and controlling the start of the vehicle motion control for the forward curve.

That is, in the vehicle motion control apparatus according to the present invention, the yaw rate response time calculating means calculates the estimated value of the road surface friction coefficient based on the running state, and calculates the estimated value of the road surface friction coefficient and the vehicle speed. Calculates the time until the yaw rate of the vehicle responds when the vehicle is steered, detects the curve ahead of the traveling road by the curve shape detecting means, calculates the distance from the vehicle to the front curve, and starts the control. The determination / control means determines and controls the start of vehicle motion control for the front curve based on the time until the yaw rate responds and the distance to the front curve.

According to a second aspect of the present invention, there is provided a vehicle motion control apparatus according to the first aspect, wherein the vehicle motion control apparatus according to the first aspect allows the vehicle to travel on the front curve based on a traveling state and a road surface state of the vehicle. Required yaw rate calculating means for calculating a lateral acceleration and calculating a yaw rate of the vehicle required when traveling on the front curve based on the allowable lateral acceleration and the radius of curvature of the front curve detected by the curve shape detecting means. And the yaw rate response time calculating means is a yaw rate response time obtained by correcting the yaw rate response time calculated based on the road surface friction coefficient estimated value and the vehicle speed in accordance with the required yaw rate.

According to a third aspect of the present invention, there is provided a vehicle motion control apparatus according to any one of the first and second aspects, wherein the control start determination / control means includes a vehicle speed and the vehicle speed. The time until the vehicle reaches the front curve is calculated based on the distance to the front curve of the vehicle calculated by the curve shape detecting means, and the arrival time to the front curve and the yaw rate response time calculating means are calculated. The start of the vehicle motion control is determined by comparing the calculated yaw rate response time.

According to a fourth aspect of the present invention, there is provided a vehicle motion control apparatus according to any one of the first and second aspects, wherein the control start determination / control means includes a vehicle speed and the vehicle speed. Based on the yaw rate response time of the vehicle calculated by the yaw rate response time calculation means, a response distance when the vehicle is motion-controlled is calculated, and the response distance and the curve to the front curve of the vehicle calculated by the curve calculation means are calculated. The start of the vehicle motion control is determined by comparing the distance with the distance.

According to a fifth aspect of the present invention, there is provided a vehicle motion control apparatus according to any one of the first and second aspects, wherein the control start determination / control means includes a vehicle speed and the vehicle speed. Based on the yaw rate response time of the vehicle calculated by the yaw rate response time calculating means, a yaw rate response distance when the vehicle is motion controlled is calculated, and the start of the vehicle motion control is determined based on the yaw rate response distance. is there.

According to a sixth aspect of the present invention, there is provided a vehicle motion control apparatus according to any one of the first, second, third, fourth and fifth aspects.
In the vehicle motion control device described in (1), the allowable lateral acceleration when traveling on the front curve is calculated based on the traveling state of the vehicle and the road surface condition, and the allowable lateral acceleration detected by the curve shape detecting means is calculated. A required yaw rate calculating means for calculating a required yaw rate of the vehicle at the front curve based on a radius of curvature of the curve, and a wheel selected based on a target yaw rate determined by the vehicle behavior control based on a running state of the vehicle In the case of the braking control in which the braking force is independently applied to the vehicle, the required yaw rate is set as a target yaw rate when the braking force is controlled.

[0014]

Embodiments of the present invention will be described below with reference to the drawings. 1 to 7 show a first embodiment of the present invention. FIG. 1 is a block diagram showing an overall configuration of a vehicle motion control device. FIG. 2 is an explanatory diagram of a configuration of a curve shape detection unit. FIG. 4 is an explanatory diagram of a method of obtaining a curve radius of curvature,
Is an explanatory diagram of correction of the radius of curvature of the obtained curve, and FIG.
FIG. 6 is an explanatory diagram of an example of point data actually obtained from the navigation device. FIG. 6 is an explanatory diagram of each case in the data reduction unit.
FIG. 7 is a flowchart of a vehicle motion control start determination for a forward curve.

In FIG. 1, reference numeral 1 denotes an overall configuration of a vehicle motion control device mounted on a vehicle. A control unit 2 of the vehicle motion control device 1 includes a vehicle speed sensor 3, a steering wheel angle sensor 4, and a yaw rate sensor 5. Each signal of the vehicle speed V, the steering wheel angle θH, the yaw rate γ, and the longitudinal acceleration detected by each of the longitudinal acceleration sensors 6 is input.

A navigation device 7 is connected to the control unit 2, and from the navigation device 7, point data indicating a road in the map information and road type information such as an expressway, a general national road, and a local road are input. It has become. Here, the navigation device 7 is, for example, a GPS receiver for receiving radio waves from GPS satellites by the Global Positioning System (GPS) to measure its own position, and a road including road information and terrain information. In the present embodiment, in particular, the control unit 2 controls the own (own vehicle) position, and the CD-ROM device stores a road map in the CD-ROM device. Point data of road data and road type information stored as information are output as needed.

Further, a road shape detecting device 8 is connected to the control unit 2 so that data relating to a road shape such as a road width is input. In the present embodiment, the road shape detection device 8 is provided so as to particularly detect a road width. For example, a stereoscopic image of an object outside the vehicle is taken by a pair of CCD cameras from different viewpoints.
A three-dimensional distance image is generated by performing a process of obtaining distance information over the entire image from the amount of positional shift corresponding to the captured one set of stereo images based on the principle of triangulation to generate a three-dimensional distance image. By performing histogram processing on the distance distribution of, the road is recognized and the road width is calculated.

The control unit 2 controls the sensors 3, 4,
5, 6, based on the respective inputs from the navigation device 7 and the road shape detecting unit 8, determine the timing of starting the motion control of the vehicle with respect to the curve ahead of the traveling road, and determine whether the running vehicle is at the timing of starting the motion control. When this occurs, a predetermined signal (hereinafter, referred to as a control start signal) for starting vehicle motion control for the forward curve is output to at least one of the braking force control device 9 and the alarm device 10. ing. Here, in the present embodiment,
The braking force control device 9 is an example of a vehicle behavior control device that detects a vehicle behavior based on a vehicle running state and performs a predetermined control on the vehicle behavior. After the calculation, the brake control is performed in accordance with the target yaw rate.

The control device 2 mainly includes a yaw rate response time calculator 11, a curve shape detector 12, a control start determination / controller 13, and a necessary yaw rate calculator 14.

The yaw rate response time calculator 11 is formed as a yaw rate response time calculator, and is mainly composed of a vehicle specification calculator 11a and a yaw rate response time calculator 11b.

The vehicle specification calculating section 11a calculates the vehicle speed V from the vehicle speed sensor 3 and the steering wheel angle θH from the steering wheel angle sensor 4 according to the method disclosed by the present applicant in Japanese Patent Application Laid-Open No. 8-2274. Based on the yaw rate γ from the yaw rate sensor 5, the equation of motion of the lateral translational motion of the vehicle is established, the cornering powers Kf, Kr of the front and rear wheels are estimated, and the road surface friction coefficient estimation value μ is calculated based on these cornering powers. It is supposed to be estimated.

The yaw rate response time calculation section 11b includes:
The vehicle speed V is input from the vehicle speed sensor 3 and the road surface friction coefficient estimated value μ is input from the vehicle specification calculating unit 11a.
Is calculated.

Here, the yaw rate response time tr is a time until the yaw rate of the vehicle responds to steering by the driver when the driver steers the steering wheel, and the yaw rate response time tr is the yaw rate response time tr. The calculation unit 11b calculates tr = (m · Lf · V) / (2 · L · Kr · μ) (1). Where m is the vehicle mass, Lf
Is the distance between the front shaft and the center of gravity, and L is the wheelbase.

The above-mentioned curve shape detecting section 12 is provided, for example, in FIG.
As shown in the figure, a three-point detecting unit 12a, a Pn-1 Pn distance calculating unit 12b, a Pn Pn + 1 distance calculating unit 12c, and a length determining unit 1
2d, a midpoint calculation unit 12e, a midpoint same distance point calculation unit 12f,
Curvature radius computing unit 12g, organizing unit 12h, data organizing unit 1
2i and a curve distance calculation unit 12j.

The three-point detector 12a detects three points on the road selected by the driver in the driving direction of the vehicle from the point data of the road input from the navigation device 7 as shown in FIG. , At predetermined intervals (from the side closer to the vehicle) as a first point Pn-1, a second point Pn, and a third point Pn + 1. These read 3
From the point, the position information of the first point Pn-1 and the second point Pn is output to the Pn-1 Pn distance calculator 12b, and the second point Pn and the third point Pn + 1 are output. Is output to the Pn Pn + 1 distance calculation unit 12c. Pn-1 = (Xn-1, Yn-1), Pn = (Xn, Y
n), Pn + 1 = (Xn + 1, Yn + 1). The representative point of the curve is Pn. Therefore, the curve at the point P1 is
From 0, P1, and P2, the curve at point P2 is represented by points P1, P2,
From P3,..., The curve of point Pn is represented by points Pn-1, Pn, Pn +
Data is calculated from 1 respectively.

The Pn-1 Pn distance calculator 12b calculates the first point based on the position information of the first point Pn-1 and the second point Pn input from the three-point detector 12a. Pn-1
And the second point Pn are calculated and output to the length determination unit 12d and the correction unit 12h.

The Pn Pn + 1 distance calculation unit 12c calculates the second point based on the position information of the second point Pn and the third point Pn + 1 input from the three-point detection unit 12a. It is configured to calculate a linear distance connecting Pn and the third point Pn + 1 and output the calculated distance to the length determination unit 12d and the correction unit 12h.

The length determining unit 12d calculates the Pn-1 Pn
The linear distance connecting the first point Pn-1 and the second point Pn input from the distance calculation unit 12b, and the second point Pn input from the Pn Pn + 1 distance calculation unit 12c The length of the straight line distance is determined by comparing the straight line distance connecting the third point Pn + 1. Then, each data (position and distance) having the shorter straight-line distance is calculated by the above-mentioned midpoint calculation unit 1.
2e and the correction unit 12g, and outputs the data (position and distance) having the longer linear distance to the midpoint equal distance point calculation unit 12f.

When both straight distances are determined to be the same length as a result of the comparison by the length determining unit 12d,
Since either of the straight lines may be used, the straight line connecting the first point Pn-1 and the second point Pn is set in advance so as to be treated as a short straight line (the second point Pn and the third point Pn-1). May be treated as a short straight line connecting the point Pn + 1).

The midpoint calculator 12e calculates half the shorter straight line distance based on the data (position and distance) of the shorter straight line input from the length determiner 12d, It is formed so as to determine the position of the midpoint on the shorter straight line. Here, a straight line connecting the first point Pn-1 and the second point Pn is a short straight line,
Assuming that the middle point is Pn-1, n = (Xn-1, n, Yn-1, n), Pn-1, n = (Xn-1, n, Yn-1, n) = ((Xn-1 + Xn) / 2, (Yn-1 + Yn) / 2) Then, each data calculated by the midpoint calculation unit 12e is
The midpoint same distance point calculation unit 12f and the curvature radius calculation unit 1
2g.

The midpoint equidistant point calculation unit 12f calculates the data (position and distance) of the long straight line input from the length determination unit 12d and the shorter data input from the midpoint calculation unit 12e. From the data of half the straight line distance, a midpoint equal distance point is determined on the longer straight line at a position half the distance of the shorter straight line distance from the second point. Here, the second point Pn and the third point Pn +
The straight line connecting 1 is a long straight line, and the midpoint and the same distance point are Pn, n + 1
= (Xn, n + 1, Yn, n + 1), Pn, n + 1 = Pn + PnPn, n + 1 = (Xn, Yn) + K2. (Xn + 1-Xn, Yn + 1-Yn ) = (Xn, n + 1 , Yn, n + 1) However, K2 = ((Xn -Xn- 1) 2 + (Yn -Yn-1
) ² ) ^1/2 / (2 · ((Xn + 1 −Xn) ² + (Yn + 1 −
Yn) ² ) ^1/2 ) The position data of the midpoint and equidistant point Pn, n + 1 calculated by the midpoint and equidistant point calculation unit 12f is output to the curvature radius calculation unit 12g. .

The curvature radius calculator 12g calculates the position data of the middle point Pn-1, n input from the middle point calculator 12e and the middle point equal distance point Pn calculated by the middle point same distance point calculator 12f. , n + 1, the shorter straight line (here, Pn-1 Pn) at the midpoint Pn-1, n as shown in FIG.
Is determined as the center position On of the curve of the traveling road, at the intersection of the straight line orthogonal to the straight line and the straight line orthogonal to the longer straight line (here, Pn Pn + 1) at the midpoint equidistant point Pn, n + 1. The radius of curvature Rn of the traveling path is calculated based on the curve center position On. The result calculated by the curvature radius calculation unit 12g is output to the correction unit 12h.

That is, On = Pn-1, n + Pn-1, n On = (Xn-1, n, Yn-1, n) + M. (Yn-Yn-1, Xn-1-Xn) (2) ) On = Pn, n + 1 + Pn, n + 1 On = (Xn, n + 1, Yn, n + 1) + N. (Yn + 1-Yn, Xn-Xn + 1) (3) Therefore, Xn -1, n + M. (Yn-Yn-1) = Xn, n + 1 + N. (Yn + 1-Yn) (4) Yn-1, n + M. (Xn-1-Xn) = Yn, n + 1 + N. (Xn-Xn + 1) (5) When M is eliminated from the above equations (4) and (5) to obtain N, N = ((Xn-1 -Xn). (Xn-1) , n−Xn, n + 1) + (Yn−1−Yn) · (Yn−1, n−Yn, n + 1)) / (Xn−1 · Yn + 1−Xn + 1 · Yn−1− Xn-1.Yn + Xn.Yn-1-Xn.Yn + 1 + Xn + 1.Yn) (6) Then, the curve center position On is represented by On = (Xon, Yon) = (Xn, n + 1 + N. Yn + 1−N · Yn, Yn, n + 1 + N · Xn−N · Xn + 1) (7) .

Accordingly, the radius of curvature Rn is obtained by the following equation.

Rn = ((Xn-Xn-1). (Yn + 1-Yn)-(Xn + 1-Xn). (Yn-Yn-1)) / | ((Xn-Xn-1). ( Yn + 1 -Yn) - (Xn + 1 -Xn) · (Yn -Yn-1)) | · ((Xon-Xn-1, n) 2 + (Yon-Yn-1, n) 2) 1 / ² (8) Here, when the radius of curvature Rn is positive, the vehicle turns left, and when the radius of curvature Rn is negative, the vehicle turns right.

The distance Lon from the curve center position On to the second point Pn, which is a representative point of the curve, is obtained by the following equation (9).

Lon = ((Xon−Xn) ² + (Yon−Yn) ² ) ^1/2 (9) The correction unit 12 h calculates the curvature radius Rn from the curvature radius calculation unit 12 g and the curve center position On. From the distance Lon to the second point Pn, and if the difference Deln exceeds an error set value described later, the curvature radius Rn is corrected and the difference Deln is changed to the error set value. Is what you do.

The final curve information (the position (Xn, Yn) of the representative point Pn of the curve, which is corrected by the correction unit 12h, or is not corrected because the difference Deln is equal to or less than the error set value. ), Distance Ln between point Pn-1 and point Pn, final radius of curvature Rn, curve center position On
, The curve angle θn of each point obtained from the angle between the straight line Pn-1 Pn and the straight line Pn Pn + 1, the curve start point Lsn (the point perpendicularly lowered from the curve center position On to the straight line Pn-1 Pn) and the point Pn The distance between -1 and the distance Lssn) from the vehicle position to the representative point of each curve are stored in memory and output to the data reduction section 12i.

The error set value is varied according to both the road width D and the shorter straight distance, and (error set value) = α ·
D (α is a constant set in accordance with the shorter straight-line distance: hereinafter, referred to as a point interval correction coefficient).

As the road width D, the value of the road width obtained from the road shape detecting device 8 is usually adopted. However, when the data cannot be obtained from the road shape detecting device 8 or the like, The road width D is set based on road type information such as an expressway, a general national road, and a local road obtained from the navigation device 7. Here, as the road width D increases, the error set value increases and the correction is not performed. This indicates that the radius of curvature Rn increases as the road width increases on an actual road. is there.

The shorter the linear distance, the larger the point interval correction coefficient α, the larger the error set value, and the direction in which the correction is not performed. For example, α = 1.2 when the shorter straight line distance is shorter than 20 m, α = 1.2 when the shorter straight line distance is shorter than 100 m.
Α = 0.3 when the distance is larger than 0.6 or 100 m. This is to prevent the correction from being performed because the fact that the straight line distance is short indicates that the point data is set finely and that the road is correctly represented.

The detailed correction by the correction unit 12h is shown in FIG.
Shown in Let the vector from Pn-1 to Pn be B1 = (Xn-
Xn-1, Yn-Yn-1) = (Xb1, Yb1), from P2 to P
B2 = (Xn + 1-Xn, Yn + 1-Yn)
) = (Xb2, Yb2).

The angle θn formed by B1 and B2 is cos θn = (Xb1 · Xb2 + Yb1 · Yb2) / (| B1 | ·
| B2 |) The error (ratio) Pdeln between Lon and Rn is Pdeln = Rn / Lon = cos (θn / 2) = ((cos θn + 1) / 2) ^1/2 (10) Therefore, the difference between Lon and Rn The difference Deln is as follows.

Deln = Lon− | Rn | = Lon · (1−Pdeln) = Lon · (1 − ((cos θn + 1) / 2) ^1/2 ) (11) where the difference Deln is an error set value. When (α · D) is exceeded, the correction is performed such that Deln = α · D with respect to the radius of curvature Rn. That is, Lon = Deln / (1 − ((cos θn + 1) / 2) ^1/2 ) = α · D / (1 − ((cos θn + 1) / 2) ^1/2 ) = α · D / (1 − ((Xb1 · Xb2 + Yb1 · Yb2 + | B1 | · | B2 |) / (2 · | B1 | · | B2 |)) ^1/2 ) Rn = Lon · Pdeln = α · D / (1-((cos θn +1) / 2) ^1/2 ) · ((cos θn +1) / 2) ^1/2 = α · D / ((2 / (cos θn +1)) ^1/2 -1) = α · D / (( 2. | B1 | · | B2 | / (Xb1 · Xb2 + Yb1 · Yb2 + | B1 | · | B2 |)) ^1/2 −1) (12) In this manner, the curve information is obtained by the curve shape detection unit 12. Therefore, the point data from the navigation device 7 which is not at a constant interval can be used as it is, and the data for the calculation can be complemented, and the calculation can be performed quickly and accurately by simple arithmetic processing without particularly complicated calculation. It is possible to determine the radius of curvature of the travel path.

The connection between the curve detection points for obtaining the radius of curvature is also natural, and a value accurately representing the actual road shape can be obtained.

Further, the calculation error is also made smaller than the actual radius of curvature of the curve, which is preferable for issuing an appropriate warning in, for example, warning / deceleration control when entering a curve.

Further, by providing the radius of curvature correction unit 12h, it is possible to calculate the radius of curvature more accurately, and to vary the error set value used as the reference for correction with the actual road shape and the number of point data. As a result, more accurate calculations can be performed. That is, in order to express that the radius of curvature increases as the road width increases on an actual road, the error setting value increases as the road width increases, and the correction is not performed. In addition, the fact that the straight line distance is short means that the point data is set finely and it can be considered that the road is correctly represented. Become.

The data arranging section 12i arranges the data for each point detected by the curve shape detecting section 12, and predetermined data of the arranged data is calculated by the curve distance calculating section 12j and the required yaw rate calculation. Since the calculation is performed by being read by the unit 14, unnecessary calculation is reduced.

In other words, the point data from the navigation device 7 may represent one curve by several points, and even if the curves are separate curves, if control is performed on one curve, the other curve will be used. In some cases, control of the curve can be omitted.

Therefore, in consideration of the above, the data rearranging section 12i applies each point data to the following four cases with respect to the case where the point data goes from the point Pn-1 to the point Pn.
They are organized into necessary point data.

Case 1: The curve becomes tight, but the point P
Deceleration distance (= Rn-1 -Rn) from n-1 to point Pn
)) (FIG. 6 (a)) | Rn-1 |> | Rn |, Rn-1 · Rn> 0, and Ln
> | Rn-1 |-| Rn |, the curve information of the points Pn-1 and Pn is required. That is, since there is a margin for deceleration from the point Pn-1 to the point Pn, independent control is required for each of the points Pn-1 and Pn.

Further, assuming that the points Pn-1 and Pn represent one curve, the curve angle θn at the point Pn is added to obtain the one curve angle (the entire curve angle θsn). Curve total angle θsn up to point Pn = curve total angle θs (n-1) + 2 · cos ^-1 (Rn / Lon) to case Pn-1 Case 2 ... The curve becomes tight and the point Pn-1 to Pn
When there is no allowance in the deceleration distance (= Rn-1 -Rn) before going to (FIG. 6 (b)) | Rn-1 |> | Rn |, Rn-1 · Rn> 0 and Ln
If <| Rn-1 |-| Rn |, the curve information of the point Pn-1 is ignored (reduced). That is, by controlling the curve of the point Pn, the point Pn−
The control for curve 1 is absorbed and the point Pn-
The curve information of 1 is ignored (reduced) because it becomes useless.

Further, assuming that the points Pn-1 and Pn represent one curve, the curve angle θn at the point Pn is added to obtain the one curve angle (the entire curve angle θsn). Curve total angle θsn up to point Pn = curve total angle θs (n-1) + 2 · cos ⁻¹ (Rn / Lon) to case Pn-1 Case 3: When the curve becomes loose (FIG. 6 (c)) If | Rn-1 | <| Rn |, Rn-1.Rn> 0, the curve information of the point Pn is ignored (reduced). That is, since the speed is reduced at the point Pn-1, the curve information of the point Pn which is a curve that is gentler than the point Pn-1 becomes unnecessary and is ignored (reduced). If Ln is long and the vehicle accelerates sufficiently (if the points Pn-1 and Pn can be regarded as independent curves), the vehicle speed may increase before reaching the point Pn. Ln
May be stored in accordance with the size of the point Pn.

Further, assuming that the points Pn-1 and Pn represent one curve, the curve angle θn at the point Pn is added to obtain this one curve angle (the entire curve angle θsn). The total angle θsn of the curve up to the point Pn = the total angle θs (n-1) of the curve up to the point Pn−1 + 2 · cos ⁻¹ (Rn / Lon) Note that the points Pn−1 and Pn can be regarded as independent curves. If it is, the curve angle θn at the point Pn is not added, and a new addition is started (determined according to the magnitude of Ln).

Case 4: When the turning direction of the curve is switched (FIG. 6 (d)) Rn-1. If Rn <0, the curve information of the point Pn is necessary. That is, the point Pn-
When going from 1 to the point Pn, since the turning direction is different, the data is not sorted only here.

Further, the total of the curve angles continuing to the point Pn-1 is defined as the total curve angle θs (n-1) to the point Pn-1.

Further, addition is started in order to obtain the total angle θsn of the curve from the point Pn. The total angle θsn of the curve up to the point Pn = 2 · cos ⁻¹ (Rn / L
on) In addition, in the above cases, when the case where one point is necessary and the case where it is unnecessary overlap, the point is ignored (reduced).

Here, the deceleration distance is defined by the radius of curvature R of the curve.
The reason for calculating the difference between n and Rn-1 is as follows. Assuming that the reference allowable approach speed at the point Pn is Vpn, the deceleration is a, and the allowable lateral acceleration is ayln, the deceleration distance = (Vp (n−1) ² −Vpn ² ) / (2 · a) = (Rn−1 · ayl (n−1) −Rn · ayln) / (2 · a) = (Rn−1−Rn) · ayl / (2 · a) The deceleration a is (１ ／) · 50% of the allowable lateral acceleration ayl. a
yl, deceleration distance = Rn-1-Rn From this result, the deceleration distance can be calculated as the curvature radii Rn and Rn-
It was calculated by the difference of one.

The curve distance calculation unit 12j receives the data from the data arrangement unit 12i and the own (own vehicle) position data from the navigation device 7, and inputs the distance lc from the entrance of the curve ahead of the traveling road to the own vehicle. Is calculated.

The control start judging / control section 13 is formed as control start judging / control means, and controls the vehicle speed V, the yaw rate response time tr calculated by the yaw rate response time calculating section 11, and the curve detecting section 12. The data indicating the distance lc from the vehicle detected at the above to the entrance of the front curve is input, and the vehicle speed V and the distance lc to the entrance of the curve are input.
Time t until the vehicle reaches the above-mentioned forward curve based on
By calculating c, and comparing the arrival time tc to the curve entrance with the yaw rate response time tr, the timing for starting the motion control for the front curve is determined. The control start signal is output to at least one of the power control device 9 and the alarm device 10.

That is, the control start determination / control section 13
Then, the arrival time tc to the curve entrance is calculated by the following expression: arrival time tc to the curve tc = (distance to the curve entrance lc) / (vehicle speed V) (13)
The control start signal is output to at least one of the braking force control device 9 and the alarm device 10 with the time when c becomes equal to or less than the yaw rate response time tr as the motion control start timing for the forward curve. ing.

Here, in the control start determination / control section 13, the yaw rate response distance lr (based on the vehicle speed V and the yaw rate response time tr, the vehicle travels until the yaw rate responds to the steering operation of the driver). Distance
, And comparing the yaw rate response distance lr with the distance lc to the curve may determine the motion control start timing for the forward curve. In this case, the yaw rate response distance lr is calculated as follows: yaw rate response distance lr = (vehicle speed V) · (yaw rate response time tr) (14), and this yaw rate response distance lr is equal to or greater than the distance lc to the corner entrance. Is the motion control start timing.

As described above, the start timing of the motion control with respect to the front curve is determined based on the yaw rate response time tr, so that the motion control with respect to the front curve is set to an appropriate timing in consideration of the responsiveness of the vehicle to the motion control. Can be set.

The necessary yaw rate calculating section 14 is mainly composed of an allowable lateral acceleration calculating section 14a and a necessary yaw rate calculating section 14b.

The allowable lateral acceleration calculating section 14a includes, for example, the vehicle speed V from the vehicle speed sensor 3, the longitudinal acceleration from the longitudinal acceleration sensor 6, the estimated road surface friction coefficient μ from the vehicle specification calculating section 11a, and the curve shape detection. The curve angle and the curve direction of the front curve are input from the section 12, and the basic value ayl of the allowable lateral acceleration is calculated according to the road friction coefficient estimated value μ.
1n and calculate the basic value ayl of this allowable lateral acceleration.
1n is corrected in the vehicle speed V, the road gradient SL, the curve angle, and the curve direction to calculate the allowable lateral acceleration ayln. Note that the road gradient SL is equal to the vehicle speed V.
Is calculated on the basis of the rate of change and the longitudinal acceleration.

The required yaw rate calculator 14b includes the curve shape detector 12, the allowable lateral acceleration calculator 14a.
From the curve radius Rn of the front curve and the allowable lateral acceleration ay
ln is input, and the required yaw rate (dΨ / dt) in the forward curve is calculated by the required yaw rate (dΨ / dt) = ((allowable lateral acceleration ayln at curve) / (curve radius Rn)) ^1/2 (15) Calculated and output to the braking force control device 9.

The braking force control device 9 determines whether the current vehicle speed V,
The steering angle θH and the yaw rate γ are input, and the differential value of the target yaw rate, the differential value of the predicted yaw rate of low μ road running, and the deviation of both differential values are calculated based on the input signals, and the yaw rate γ and the target yaw rate are calculated. Calculate the deviation of the vehicle, based on these values, calculate the target braking force to correct the understeer tendency of the vehicle, or the oversteer tendency, and in order to correct the understeer tendency of the vehicle, turn the inner rear wheel in the turning direction, In order to correct the oversteer tendency, the front wheel outside the turning direction is selected as a braking wheel to apply a braking force, a control signal is output to a brake driving unit (not shown), and a target braking force is applied to the selected wheel to control the braking force. It is formed so that.

Here, when the control start signal is input from the control start determination / control section 13 of the control section 2, the required yaw rate calculation section 14b
The required yaw rate (dΨ) at the forward curve calculated by
/ Dt) is set as a target yaw rate, and braking force control is performed based on the set target yaw rate.

That is, the braking force control device 9 controls the behavior of the vehicle in accordance with the current driving condition except when the vehicle is traveling on a curve. On the other hand, when the vehicle is traveling on a curve, the vehicle is controlled at a predetermined timing before entering the curve. When the control start signal is input,
By setting the required yaw rate (dΨ / dt) as the target yaw rate, vehicle behavior control according to the road condition of the front curve is performed.

The device for controlling the behavior of the vehicle is not limited to the braking force control device 9. For example, in a four-wheel steering vehicle using a yaw rate as a control law parameter,
The control unit 2 is connected to a four-wheel steering control device, and when a control start signal is input from the control unit 2 to the four-wheel steering control device, the required yaw rate (dΨ / dt) as in the case of the braking force control device 9. ) May be set as the target yaw rate to perform yaw angular velocity proportional steering control or front wheel proportional steering, or control such as a combination thereof. Further, the braking force control device 9 and the four-wheel steering control device may be combined.

The warning device 10 is for warning the driver and prompting the driver to control the brake operation and the steering of the steering wheel so as to maintain the safety when traveling on a curve ahead of the travel road. When a control start signal from the control unit 2 is input, a predetermined alarm unit (not shown) is driven to generate an alarm such as a buzzer, an audio alarm, and a warning lamp. That is, the alarm device 10 issues an alarm in accordance with the timing at which the control start signal is input to the front curve, thereby giving an alarm at an appropriate timing earlier by a predetermined amount in consideration of the vehicle behavior delay. Is performed.

Next, the control for determining the start timing of the vehicle motion control for the forward curve according to the first embodiment of the present invention will be described with reference to the flowchart of FIG. This program is executed, for example, at predetermined time intervals. When the program starts, in step (hereinafter abbreviated as S) 101, a vehicle speed sensor 3, a steering wheel angle sensor 4, a yaw rate sensor 5,
Each signal of the vehicle speed V, the steering wheel angle θH, the yaw rate γ, and the longitudinal acceleration is read from the longitudinal acceleration sensor 6, and the point data and the road type information from the navigation device 7 and the road width data from the road shape detecting device 8 are read, and S 102.
Proceed to.

At S102, the vehicle specification calculation unit 11a
Then, the cornering powers Kf and Kr are estimated based on the vehicle speed V, the steering wheel angle θH, and the yaw rate γ, and the road surface friction coefficient estimation value μ is calculated using the cornering powers Kf and Kr, and S1
Go to 03.

In S103, the yaw rate response time calculator 11b calculates the vehicle speed V and the road surface friction coefficient estimated value μ.
, The yaw rate response time tr is calculated by the above equation (1), and the process proceeds to S104.

In step S104, the curve shape detector 12
Based on the point data and the road type information from the navigation device 7 and the road width data from the road shape detection device 8, a curve ahead of the traveling road is detected, and the distance lc to the entrance of the detected forward curve is detected. Is calculated, and the process proceeds to S105.

In step S105, the necessary yaw rate calculation unit 14 calculates the allowable lateral acceleration a based on the vehicle speed V, the road surface friction coefficient estimated value μ, the curve angle and the curve direction of the forward curve.
yln is calculated, and the required yaw rate (d に よ り / dt) is calculated from equation (15) based on the allowable lateral acceleration ayln and the curve radius Rn of the forward curve, and the process proceeds to S106.

In S106, the control start determination / control unit 13 determines the vehicle speed V and the distance l to the entrance of the front curve.
Based on c, the arrival time tc to the curve by the above equation (13)
Is calculated, and the arrival time tc to the curve is compared with the yaw rate response time tr. When the arrival time tc to the curve is longer than the yaw rate response time tr, it is determined that the timing is not the vehicle motion control start timing. And
It returns to S101.

On the other hand, if the arrival time tc to the curve or the yaw rate response time tr is equal to or less than the yaw rate response time tr in S106, it is determined that it is the vehicle motion control start timing.
Proceeding to S107, the braking force control device 9 and the alarm device 10
After outputting a predetermined signal (control start signal) for starting the vehicle motion control for the front curve, the routine exits.

Here, when the control start signal is input to the braking force control device 9, the required yaw rate calculation unit 1
The required yaw rate in the forward curve calculated in 4b is set as a target yaw rate, and braking force control is performed based on the target yaw rate. That is, by determining the motion control start timing in consideration of the response delay of the vehicle based on the yaw rate response time, the control start signal is input at an appropriate timing before entering the curve, and the control start signal is input. Since the required yaw rate (dΨ / dt) is set as the target yaw rate and the vehicle raising control according to the road condition of the forward curve is performed in advance at an appropriate timing before entering the curve, the optimum vehicle traveling state at the time of entering the curve. Can be maintained, and a high level of safety can be maintained.

When the control start signal is input to the alarm device 10, the alarm device 10 drives an alarm means (not shown) to generate an alarm such as a buzzer, an audio alarm, a warning light, etc. Prompts the user to perform predetermined operations such as steering and brake control. That is, by determining the motion control start timing in consideration of the response delay of the vehicle based on the yaw rate response time, the control start signal is input at an appropriate timing before entering the curve, and the control start signal is input. By issuing a predetermined warning, the driver can be prompted in advance to control the vehicle with respect to the front curve, and a high level of safety can be maintained.

As described above, according to the present embodiment, the yaw rate response time is calculated based on the vehicle speed V and the estimated value of the road surface friction coefficient μ, and the yaw rate response delay of the vehicle is considered based on the yaw rate response time. Since the motion control start timing can be determined, the motion control of the vehicle with respect to the forward curve can be performed at an appropriate timing, and a high level of safety can be maintained.

Next, FIGS. 8 to 10 show a second embodiment of the present invention. FIG. 8 is a block diagram showing the overall configuration of the vehicle motion control device. FIG. FIG. 10 is an explanatory diagram of the characteristics of the required yaw rate, and FIG. 10 is a flowchart of a vehicle motion control start determination for a forward curve. In the above-described first embodiment, the yaw rate response time calculation unit 11 is mainly composed of the vehicle specification calculation unit 11a and the yaw rate response time calculation unit 11b. While the estimated value μ is calculated and the yaw rate response time calculation unit 11b calculates the yaw rate response time tr based on the vehicle speed V and the road surface friction coefficient estimated value μ, the yaw rate response time calculation unit in the present embodiment. Reference numeral 17 mainly includes a vehicle specification calculation unit 17a, a yaw rate response time reference value calculation unit 17b, and a yaw rate response time reference value correction unit 17c.
a, the yaw rate response time reference value tr1 is calculated based on the vehicle speed V and the road surface friction coefficient estimated value μ by the yaw rate response time reference value calculation unit 17b. The value correction unit 17c calculates the yaw rate response time reference value tr1 as the required yaw rate (dΨ
/ Dt) to calculate the yaw rate response time tr. Other controls are substantially the same as those in the first embodiment described above, and the components performing these controls are denoted by the same reference numerals and description thereof is omitted.

The vehicle specification calculating section 17a performs the above-described first operation.
The vehicle speed V from the vehicle speed sensor 3, the steering wheel angle θH from the steering wheel angle sensor 4, and the yaw rate γ from the yaw rate sensor 5, as in the vehicle specification calculating unit 11a shown in the embodiment.
Are input, and the cornering powers Kf and Kr of the front and rear wheels are estimated based on these data, and the road surface friction coefficient estimated value μ is estimated.

The yaw rate response time reference value calculating section 17
In b, the vehicle speed V from the vehicle speed sensor 3 and the road surface friction coefficient estimation value μ from the vehicle specification calculation unit 11a are input, and the yaw rate response time reference value tr1 of the vehicle is calculated based on these. Here, the calculation of the yaw rate response time reference value tr1 is based on the method of calculating the yaw rate response time tr in the yaw rate response time calculation unit 11b of the first embodiment, that is, the method of calculating by the equation (1). The same is true.

The yaw rate response time reference value correction section 17
c is the required yaw rate (dΨ) from the required yaw rate calculator 14b and the yaw rate response time reference value calculator 17b.
/ Dt), data indicating the yaw rate response time reference value tr1 is input, and the yaw rate response time reference value tr1 is corrected according to the required yaw rate (dΨ / dt) to calculate the yaw rate response time tr, and control start determination is performed.・ Control unit 13
Output.

That is, the yaw rate response time reference value correcting section 17c calculates the yaw rate response time tr by, for example, the following equation. Yaw rate response time tr = (Yaw rate response time reference value tr1) · (correction coefficient K) (16) Here, as shown in FIG. 9, for example, the required yaw rate (dΨ / dt) is large as shown in FIG. Is a coefficient that is predetermined so as to increase linearly. That is, although the time constant of the yaw rate response is determined by the vehicle specifications, when the steering speed of the driver needs to be large, it is necessary to start the vehicle motion control accordingly. Therefore, by setting the yaw rate response time tr to be longer, the control is started even if the time to reach the curve is longer.

Next, the control for determining the start timing of the vehicle motion control for the forward curve according to the second embodiment of the present invention will be described with reference to the flowchart of FIG. This program is executed, for example, every predetermined time. When the program starts, in step S201, the vehicle speed V, the steering wheel angle θH, the yaw rate γ are obtained from the vehicle speed sensor 3, the steering wheel angle sensor 4, the yaw rate sensor 5, and the longitudinal acceleration sensor 6. ,
Each signal of the longitudinal acceleration is read, point data and road type information are read from the navigation device 7, and road width data is read from the road shape detection device 8, and the process proceeds to S202.

At S202, the vehicle specification calculation unit 17a
Then, the cornering powers Kf and Kr are estimated based on the vehicle speed V, the steering wheel angle θH, and the yaw rate γ, and the road surface friction coefficient estimation value μ is calculated using the cornering powers Kf and Kr, and S2
Go to 03.

In S203, the yaw rate response time reference value calculating section 17b replaces the yaw rate response time reference value tr1 with tr in the above equation (1) by tr1 based on the vehicle speed V and the road friction coefficient estimated value μ. S2
Go to 04.

In step S204, the curve shape detector 12
Based on the point data and the road type information from the navigation device 7 and the road width data from the road shape detection device 8, a curve ahead of the traveling road is detected, and the distance lc to the entrance of the detected forward curve is detected. Is calculated, and the process proceeds to S205.

In step S205, the necessary yaw rate calculation unit 14 calculates the allowable lateral acceleration a based on the vehicle speed V, the road surface friction coefficient estimated value μ, the curve angle and the curve direction of the front curve.
yln is calculated, and the required yaw rate (d） / dt) is calculated based on the permissible lateral acceleration ayln and the curve radius Rn of the forward curve by the above equation (15), and the process proceeds to S206.

In step S206, the yaw rate response time reference value correction section 17c corrects the yaw rate response time reference value tr1 according to the required yaw rate (dΨ / dt), and calculates the yaw rate response time tr by the above equation (16). Then, the process proceeds to S207.

In S207, the control start determination / control section 13 determines the vehicle speed V and the distance l to the entrance of the front curve.
Based on c, the arrival time tc to the curve by the above equation (13)
Is calculated, and the arrival time tc to the curve is compared with the yaw rate response time tr. When the arrival time tc to the curve is longer than the yaw rate response time tr, it is determined that the timing is not the vehicle motion control start timing. And
It returns to S201.

On the other hand, when the arrival time tc to the curve or the yaw rate response time tr is equal to or shorter than the above-described time at S207, it is determined that the vehicle motion control start timing is reached.
Proceeding to S208, the braking force control device 9 and the alarm device 10
After outputting a predetermined signal (control start signal) for starting the vehicle motion control for the front curve, the routine exits.

As described above, in the present embodiment, the vehicle speed V,
The yaw rate response time reference value tr1 is obtained from the cornering power Kr of the rear wheels of the vehicle and the road friction coefficient estimated value μ, and this yaw rate response time reference value tr1 is calculated as the required yaw rate (dΨ / d).
By correcting according to t), it is possible to calculate the yaw rate response time tr more accurately than the yaw rate response time tr obtained in the first embodiment.

Next, FIGS. 11 to 14 show a third embodiment of the present invention, FIG. 11 is a block diagram showing the overall configuration of a vehicle motion control device, and FIG. 12 is a control start determination / control unit. FIG. 13 is a flowchart of vehicle motion control,
FIG. 14 is a flowchart of a subroutine for control start determination. In this embodiment, the applicant performs the vehicle motion control shown in Japanese Patent Application No. 9-245788 in consideration of the yaw rate response of the vehicle.

In FIG. 11, reference numeral 1b designates the overall configuration of a vehicle motion control device mounted on a vehicle. The control unit 2b of the vehicle motion control device 1b includes a vehicle speed sensor 3, a steering wheel angle sensor 4, a yaw rate sensor 5 Signals of the vehicle speed V, the steering wheel angle θH, the yaw rate γ, the longitudinal acceleration detected by each of the longitudinal acceleration sensors 6, point data and road type information of the road data from the navigation device 7, and the road from the road shape detecting device 8. Data relating to the shape of the road, such as the width, and an operation signal (a signal indicating a turning operation of the driver) from the turn signal switch 31 are input.

The control section 2b controls the sensors 3, 4,
5, 6, based on each input from the navigation device 7, the road shape detection device 8, and the turn signal switch 31, calculate whether or not the curve ahead of the traveling road can be turned sufficiently stably, and if necessary. A warning is given to the driver through a warning device 35 such as a buzzer, an audio warning, a warning light, and the like. When forced deceleration is required (during forced deceleration), a transmission control device is added in addition to the warning. 32 downshift, engine control unit 3
3, the supercharging pressure is reduced, the fuel is cut and the throttle opening is fully closed (closed control), and the brake control unit 34 is operated to perform the brake operation and the brake force increase (warning / warning). Deceleration control is performed). Here, in the present embodiment, each of the above devices 32 to 35
The vehicle behavior control and the warning output by are performed at a timing in which the yaw rate response distance of the vehicle is considered.

The transmission control device 32 includes:
The control section 2b performs transmission-related control such as vehicle shift control, lock-up control, and line pressure control, and outputs the current shift position to the control section 2b and executes shift-down execution from the control section 2b. When a signal is input, a downshift is performed.

The engine control device 33 performs engine-related controls such as fuel injection control, ignition timing control, air-fuel ratio control, supercharging pressure control, throttle opening control, and the like. While outputting the boost pressure control information, the fuel cut information, and the throttle opening control information, when the boost pressure down execution signal is input from the control unit 2b, the boost pressure down is performed, and the fuel cut execution signal is output. When the signal is inputted, the fuel cut is executed, and when the signal for executing the throttle opening fully closed (close control) is inputted, the throttle opening is fully closed (closed control).

The brake control device 34 is provided with an anti-lock brake control by connecting a hydraulic unit,
It performs automatic brake control and the like, and outputs the current brake operation state to the control unit 2b, and when a signal for executing the brake operation and increasing the brake force is input from the control unit 2b, the brake is applied. It operates and increases the braking force.

The alarm device 35 includes a chime buzzer,
It is composed of an audio alarm, a warning light, etc., or a combination thereof. For example, at the time of an alarm, "Please decelerate for a curve" previously recorded on the CD-ROM of the navigation device 7 or the like. Or a chime / buzzer sound only, and at the time of forced deceleration, an audio warning such as "Decelerate due to curve" and a buzzer and warning light are lit. The method of alarming is not limited to this, and a warning at the time of an alarm and a warning at the time of a forced deceleration may be performed by using a plurality of audio warnings. In addition, the position of the curve to be controlled for alarm / deceleration is indicated by an information display unit (not shown) of the navigation device 7.
May be displayed in a color on the map of the map or by voice guidance.

The control section 2b mainly includes a yaw rate response time calculation section 11, a curve shape detection section 12, an allowable lateral acceleration calculation section 36, and a control start determination / control section 38.

The permissible lateral acceleration calculating section 36 calculates, for example,
From the vehicle speed sensor 3 to the vehicle speed V, the longitudinal acceleration sensor 6
, The road surface friction coefficient estimation value μ from the vehicle specification calculation unit 11a, the curve angle and the curve direction of the front curve from the curve shape detection unit 12, and the allowable lateral width according to the road surface friction coefficient estimation value μ. The basic value ayl1n of the acceleration is calculated, and the basic value ayl1n of the allowable lateral acceleration is corrected in a predetermined manner based on the vehicle speed V, the road gradient SL, the curve angle and the curve direction to calculate the allowable lateral acceleration ayln. . The road gradient SL is calculated based on the rate of change of the vehicle speed V and the longitudinal acceleration.

The control start determination / control unit 38 determines the vehicle speed V from the vehicle speed sensor 3, the steering wheel angle θH from the steering wheel angle sensor 4, the longitudinal acceleration from the longitudinal acceleration sensor 6, and the road surface friction from the vehicle specification calculating unit 11a. The coefficient estimated value μ, the yaw rate response time tr from the yaw rate response time calculator 11b, the curve radius Rn from the curve shape detector 12, the operation signal from the turn signal switch 31, the allowable lateral acceleration ayl from the allowable lateral acceleration calculator 36.
n. In response to each of these inputs, a signal is output to the alarm device 35 for performing the alarm control, and a signal is output to each of the control devices 32 to 34 for performing the deceleration control.

More specifically, as shown in FIG. 12, the control start determination / control section 38 includes a reference allowable approach speed setting section 40, an allowable deceleration setting section 41, and a control execution determination section 4
2. It mainly comprises a deceleration speed calculation / output unit 43 and an alarm speed calculation / output unit 44.

The yaw rate response distance calculating section 37 receives the vehicle speed V from the vehicle speed sensor 3 and the yaw rate response time tr from the yaw rate response time calculating section 11b. For example, the yaw rate response distance calculating section 37 has been described in the first embodiment (14). ) Is used to calculate the yaw rate response distance lr.

The reference allowable approach speed setting unit 40 determines the allowable approach speed (based on the curvature radius Rn of the curve from the curve shape detecting unit 12 and the allowable lateral acceleration ayln from the allowable lateral acceleration calculating unit 36). Reference allowable approach speed Vpn)
Is set, and the set reference allowable approach speed Vpn is output to the deceleration speed calculation / output unit 43 and the alarm speed calculation / output unit 44.

The calculation of the reference allowable approach speed Vpn in the reference allowable approach speed setting section 40 is performed by the following equation. Vpn = (ayln.Rn) ^1/2 (17)

The permissible deceleration setting section 41 sets a deceleration (permissible deceleration XgLim) that can be tolerated by the vehicle according to the road friction coefficient estimated value μ and the road conditions of the road gradient SL. Are output to the deceleration speed calculation / output unit 43 and the alarm speed calculation / output unit 44.

That is, the permissible deceleration setting unit 41 firstly executes the vehicle specification calculation unit 11 by, for example,
The basic value XgLim0 is calculated from the road friction coefficient estimated value μ calculated in a.
Is set. XgLim0 = μ · g · Kμ2 (18) Here, the coefficient Kμ2 is set to, for example, a value of about Kμ2 = 0.8 in consideration of the road surface utilization during full braking. The constant axc is set in advance by experiments, calculations, and the like, and takes a value of, for example, 5 m / s ² .

Further, in the allowable deceleration setting section 41,
As shown in the following equation (19), a correction is made for a change in the braking distance due to the road gradient SL, and at the same time, a large deceleration is obtained on the ascending gradient and a small deceleration on the descending gradient so that the deceleration felt by the driver is constant. The basic value XgLim0 is corrected so as to obtain the speed, and the allowable deceleration XgLim is obtained. With such a correction, the control start timing takes into account the deceleration component of gravity due to the gradient on an uphill and the acceleration component of gravity on a downhill. XgLim = XgLim0 + gSL / 100 (19)

The control execution judging section 42 receives the signal from the turn signal switch 31, the signal from the vehicle speed sensor 3, and the signal from the steering wheel angle sensor 4, and uses these signals to perform alarm control. Release (OF
F), release of alarm / deceleration control (OFF), change from deceleration control to alarm control, and output to the deceleration speed calculation / output unit 43 and alarm speed calculation / output unit 44. .

In other words, when the driver operates the turn signal switch 31, the driver is expected to enter a straight road that is not included in the map information of the navigation device 7 or to incorrectly judge a curve and an intersection.・ Deceleration control is released.

If the driver operates the steering wheel with a steering amount equal to or larger than the preset steering amount based on the signal from the steering wheel angle sensor 4, the vehicle is expected to travel on a course other than the assumed course. The alarm / deceleration control is released.

When performing the alarm control based on the signal from the vehicle speed sensor 3, the driver determines the deceleration (0.5
If the driver has already decelerated by XgLim) or more, the driver is already taking action and there is no need to issue an alarm, so the alarm control is canceled. In this case, if a plurality of warning methods can be changed, the warning may be performed by changing the warning method.

When the deceleration control is performed based on the signal from the vehicle speed sensor 3, if the driver has already decelerated at the deceleration (0.8 · XgLim) or more in the deceleration determination, the driver Has already been dealt with, and there is no need to perform forced deceleration, so that deceleration control is changed to alarm control.

The alarm speed calculation / output unit 44 receives points from the curve distance detection unit 12 in front of the vehicle,.
, Pn,..., And the distance Ln between these points
Is calculated, the distance Ln, the allowable deceleration XgLim set by the allowable deceleration setting unit 41, and the reference allowable entry speed V set by the reference allowable entry speed setting unit 40.
Based on pn, an allowable approach speed as a reference for alarm control is calculated as an alarm speed VA. Each alarm speed VA calculated by the alarm speed calculation / output unit 44 is stored in a predetermined memory together with a deceleration speed VB described later.

Further, the yaw rate response distance lr from the yaw rate response distance calculation section 37 is input to the alarm speed calculation / output section 44. For example, an acceleration capable of decelerating a threshold value for an alarm in consideration of the yaw rate response distance lr is provided. That is, the speed is set as 50% of the allowable deceleration XgLim.

The arrival point P1 (points P2 to P2) with respect to the preceding point P2
Alarm judgment speed at point P1 = L2 (alarm speed VA = V)
A12) is passable speed at the point P2 (relative = reference allowable approaching speed ^{Vp2), VA12 = (Vp2 2} +2 · (0.5 · XgLim) · (L2
−lr)) ^1/2 Similarly, the arrival point P1 (points P3 to P) with respect to the preceding point P3
(Relative = VA13) the reference allowable approach speed ^{Vp3, VA13 = (Vp3 2 +2} · (0.5 · XgLim) 1 = L2 + L3) alert speed at VA · (L2
+ L3 -lr)) ^{1/2 The} arrival point Pα (point Pβ to point Pα) with respect to the preceding point Pβ
= L (α + 1) +... + Lβ) Alarm speed VA (= VA)
αβ) is VA αβ = (VPβ ² + 2 · (0.5 · XgLim) · (L (α + 1) +... + Lβ−lr)) ^{1/2 with} respect to the reference allowable approach speed VPβ. In the speed calculation / output unit 44, each of the alarm speeds VA1 is calculated based on the distance L1 and the allowable deceleration XgLim.
β (VA1 (n + 1) to Vp1) are respectively assigned to the current position point P0.
Is calculated as an estimated alarm speed VAP, and the estimated alarm speed VAP is compared with the vehicle speed V. When the vehicle speed V is equal to or higher than the estimated alarm speed VAP, a signal is issued to perform alarm control. 35. The execution of the alarm control is performed by the control execution determination unit 4.
2 or can be started by a change from deceleration control.

Here, the estimated warning speed VAP is calculated as follows. From the above equation (20), the arrival point P0 (point Pβ to point P0 = L1 + L2 +... +
The warning speed VA (= VA0β = VAP) at Lβ) is VAP = (VPβ ² + 2 · (0.5 · XgLim) · (L1) with respect to the reference allowable approach speed VPβ.
+ L2 +... + Lβ-lr)) ^1/2 Also, the arrival point P1 (point Pβ to point P1) with respect to the preceding point Pβ
(Relative = VA1β) the reference allowable approach speed ^{VPβ, VA1β = (VPβ 2 +2} · (0.5 · XgLim) = L2 + ... + an alarm at L?) Speed VA · (L
2 + ... + Lβ-lr) ) 1/2 Therefore, from these two ^{equations, VAP = (VA1β 2 +2 ·} (0.5 · XgLim) · (L1-lr)) 1/2 ... (21)

The deceleration speed calculation / output unit 43 outputs the points in front of the vehicle,..., Pn−1,
Pn,... Are input to calculate the distance Ln between these points, and the allowable deceleration setting unit 41
The allowable deceleration XgLim set in Step 4 and the reference allowable approach speed Vpn set in the reference allowable approach speed setting unit 40 are input, and the allowable approach speed used as the reference for the deceleration control is set to the deceleration speed VB.
Is calculated.

Further, the yaw rate response distance lr is input from the yaw rate response distance calculation section 37 to the deceleration speed calculation / output section 43. For example, a threshold value for forced deceleration taking the yaw rate response distance lr into consideration can be reduced. The acceleration is set as 80% of the allowable deceleration XgLim.

The arrival point P1 relative to the preceding point P2 (points P2 to P2)
Judgment speed (deceleration speed VB) for forced deceleration at point P1 = L2
= VB12) is passable speed at the point P2 (relative = reference allowable approaching speed ^{Vp2), VB12 = (Vp2 2} +2 · (0.8 · XgLim) · (L2
−lr)) ^1/2 Similarly, the arrival point P1 (points P3 to P
(Relative = VB13) the reference allowable approach speed ^{Vp3, VB13 = (Vp3 2 +2} · (0.8 · XgLim) 1 = L2 + L3) reduction rate in the VB · (L2
+ L3 -lr)) ^{1/2 The} arrival point Pα (point Pβ to point Pα) with respect to the preceding point Pβ
= L (α + 1) +... + Lβ)
αβ) is VBαβ = (VPβ ² + 2 · (0.8 · XgLim) · (L (α + 1) +... + Lβ−lr)) ^{1/2 with} respect to the reference allowable approach speed VPβ. The speed calculation / output unit 43 calculates the deceleration speeds VB1 based on the distance L1 and the allowable deceleration XgLim.
β (VB1 (n + 1) to Vp1) is respectively assigned to the current position point P0.
The estimated deceleration speed VBP is calculated as the estimated deceleration speed VBP, and the estimated deceleration speed VBP and the vehicle speed V are compared. In accordance with the speed XgLim, a predetermined output is output to each of the control devices 32-34. The execution of the deceleration control is performed by the control execution determination unit 4.
2 or a change to the alarm control is possible. Note that the alarm device 3
A signal is output from 5 so as to give an alarm to that effect (lighting of the lamp, generation of sound, etc.).

The estimated deceleration speed VBP is calculated as follows. From the above equation (22), the preceding point Pβ
From the arrival point P0 (point Pβ to point P0 = L1 + L2 +...
+ Lβ), the deceleration speed VB (= VB0β = VBP) is VBP = (VPβ ² + 2 · (0.8 · XgLim) · (L1) with respect to the reference allowable approach speed VPβ.
+ L2 +... + Lβ-lr)) ^1/2 Also, the arrival point P1 with respect to the preceding point Pβ (point Pβ to point P1
(Relative = VB1β) the reference allowable approach speed ^{VPβ, VB1β = (VPβ 2 +2} · (0.8 · XgLim) = L2 + ... + an alarm at L?) Speed VB · (L
2 + ... + L?-Lr)) ^1/2 Therefore, these two ^{equations, VBP = (VB1β 2 +2 ·} (0.8 · XgLim) · L1 -lr) The ^1/2 (23), the deceleration control Is, based on the allowable deceleration XgLim, the boost pressure reduction +
Execution of fuel cut or the engine control device 3
(3) Execution of supercharging pressure down + fuel cut + throttle opening degree closing control or execution of supercharging pressure down + fuel cut + throttle opening degree fully closing for the engine control unit 33 + for the transmission control unit 32 Executing a downshift, or performing a boost pressure reduction on the engine control unit 33 + executing a fuel cut + fully opening the throttle opening + executing a downshift on the transmission control unit 32 + a braking control unit 34
, And either one of the brake operation and the execution of the brake force increase is selected and performed.

Next, the vehicle motion control start control according to the third embodiment of the present invention will be described with reference to the flowchart of FIG. This program is executed, for example, every predetermined time, and when the program starts, step S301
Then, from the vehicle speed sensor 3, the steering wheel angle sensor 4, the yaw rate sensor 5, the longitudinal acceleration sensor 6, and the turn signal switch 31, the respective signals of the vehicle speed V, the steering wheel angle θH, the yaw rate γ, the longitudinal acceleration, and the operation signal are read, and the navigation device is read. 7, the point data and road type information, and the road width data from the road shape detecting device 8 are read, and the process proceeds to S302.

In S302, the vehicle specification calculation unit 11a
Then, the cornering powers Kf and Kr are estimated based on the vehicle speed V, the steering wheel angle θH, and the yaw rate γ, and the road surface friction coefficient estimation value μ is calculated using the cornering powers Kf and Kr.
Go to 03.

In S303, the yaw rate response time reference value calculating section 11b calculates the yaw rate response time t by the above equation (1) based on the vehicle speed V and the road friction coefficient estimated value μ.
Calculate r, and proceed to S304.

In S304, the curve shape detector 12
Based on the point data and the road type information from the navigation device 7 and the road width data from the road shape detection device 8, a curve ahead of the traveling road is detected, and the distance lc to the entrance of the detected forward curve is detected. Is calculated, and the process proceeds to S305.

In S305, the allowable lateral acceleration calculating section 3
6, the allowable lateral acceleration ayl based on the vehicle speed V, the road surface friction coefficient estimated value μ, the curve angle and the curve direction of the forward curve.
n is calculated, and the process proceeds to S306.

In step S306, the control start determination / control section 38 determines the start of control of the transmission control device 32, the engine control device 33, the brake control device 34, and the alarm device 35 according to a subroutine described below. After executing necessary control by the control devices 32 to 35, the process exits from the routine.

Next, when the subroutine of the control start judgment performed by the control start judgment / control section 38 starts, in S311, the yaw rate response distance calculation section 37
Then, based on the vehicle speed V and the yaw rate response time tr, the yaw rate response distance lr is calculated by the above equation (14).
Proceed to 312.

In step S312, the reference allowable approach speed setting unit 40 sets the curvature radius Rn of the curve and the allowable lateral acceleration ay.
The reference allowable approach speed Vpn is set based on ln, and the process proceeds to S313.

At S313, the allowable deceleration setting unit 41
Then, the allowable deceleration XgLim is set according to the road surface friction coefficient estimated value μ and the road condition of the road gradient SL, and the process proceeds to S314.

At step S314, it is determined whether or not the turn signal switch 31 has been operated. If the turn signal switch 31 has been operated, the process proceeds to step S315.
Then, the deceleration control is released (OFF), and the process proceeds to S316.
Cancel (OFF) the alarm control and exit the routine.

On the other hand, if it is determined in step S314 that the turn signal switch 7 has not been operated, the flow advances to step S317 to determine whether or not the amount of steering by the driver based on a signal from the steering wheel angle sensor 4 is equal to or greater than a preset value. Is determined. If the amount of steering by the driver is equal to or greater than the set value, the process proceeds to S315, where the deceleration control is released (OFF),
Proceeding to S316, the alarm control is released (OFF), and the routine exits.

As a result of the determination in S317, if the steering amount is smaller than the set value (the turn signal switch 31
Is OFF and the steering amount is small), the process proceeds to S318, and the deceleration speed calculation / output unit 43 outputs the current position point based on each data (each deceleration speed VB1β (VB1 (n + 1) to Vp1)) at the point P1. The deceleration speed at P0 is estimated and calculated (estimated deceleration speed VBP). At this time, the calculation of each estimated deceleration speed is performed in consideration of the yaw rate response distance lr.

Then, the program proceeds to S319, where the vehicle speed V is compared with the above-mentioned estimated deceleration speeds VBP. If the vehicle speed V is at least one of the above-mentioned estimated deceleration speeds VBP (V ≧
VBP), and proceeds to S320.

In S320, based on the vehicle speed V, it is determined whether or not the driver has already decelerated at the deceleration (0.8 · XgLim) or more in the deceleration determination. If the driver has not performed deceleration equal to or more than the deceleration in the deceleration determination, it is determined that deceleration is necessary, and the process proceeds to S321 to execute deceleration control (ON) and exit from the routine.

In S320, when the driver has already decelerated at the deceleration (0.8 · XgLim) or more in the deceleration judgment, the driver is already taking measures and it is necessary to perform forced deceleration. It is determined that there is not, and the process proceeds to S322 to release (OFF) the deceleration control, and further proceeds to S323 to execute (ON) the alarm control (that is, change from deceleration control to alarm control) and exit the routine.

On the other hand, as a result of the comparison between the vehicle speed V and each of the estimated deceleration speeds VBP in S319, if the vehicle speed V is lower than all the estimated deceleration speeds VBP, S324 is executed.
Then, the deceleration control is released (OFF), and the flow proceeds to S325. At the alarm speed calculation / output unit 44, the current position point is determined based on each data (each alarm speed VA1β (VA1 (n + 1) to Vp1)) at the point P1. The alarm speed at P0 is estimated and calculated (estimated alarm speed VAP). At this time, the calculation of each of the estimated warning speeds is performed in consideration of the yaw rate response distance lr, similarly to the calculation of the estimated deceleration speed.

Then, the program proceeds to S326, in which the vehicle speed V is compared with each of the above-mentioned estimated warning speeds VAP. If the vehicle speed V is at least one of the above-mentioned estimated warning speeds VAP, (V ≧
VAP), and proceeds to S327.

In S327, it is determined based on the vehicle speed V whether or not the driver has already decelerated at or above the deceleration (0.5 · XgLim) in the alarm determination. If the driver has not decelerated at or above the deceleration in the alarm determination, it is determined that an alarm is necessary, and the process proceeds to S323 to execute the alarm control (ON) and exit from the routine.

If the driver has already decelerated at the deceleration (0.5.times.XgLim) or more in the alarm judgment in S327, the driver is already coping and needs to give an alarm. It is determined that there is no alarm control, and the process proceeds to S328 and the alarm control is released (O
FF) and exit the routine.

Here, the alarm control is executed in step S323 (O
As described above, N) is performed by the alarm device 35 configured by a chime buzzer, an audio alarm, a warning light, or a combination thereof, and in the alarm control performed through S327, for example, “ Please decelerate because of the curve. "Or an alarm with only the chime / buzzer sound. In the alarm control performed through S322, for example, an alarm with only the chime / buzzer sound is issued.

Also, the deceleration control execution (O
In the case of N), the alarm device 35 emits an audio alarm such as "decelerate because of a curve" and turns on a buzzer and a warning light. Here, the deceleration control performed by the deceleration speed calculation / output unit 43 is performed to reduce the supercharging pressure to the engine control device 33 in accordance with the allowable deceleration XgLim.
Execution of fuel cut or the engine control device 3
(3) Execution of supercharging pressure down + fuel cut + throttle opening degree closing control or execution of supercharging pressure down + fuel cut + throttle opening degree fully closing for the engine control unit 33 + for the transmission control unit 32 Executing a downshift, or performing a boost pressure reduction on the engine control unit 33 + executing a fuel cut + fully opening the throttle opening + executing a downshift on the transmission control unit 32 + a braking control unit 34
, And either of the braking operation and the execution of the braking force increase are selectively performed.

The above S312, S317, S320,
Each determination process in S327 is performed by the control execution determination unit 31.

As described above, in the present embodiment, similarly to the first and second embodiments of the present invention, the vehicle motion control for the forward curve takes into account the yaw rate response (yaw rate response distance) of the vehicle. It can be carried out at the appropriate timing, and a high level of safety can be maintained.

[0149]

As described above, according to the present invention,
The yaw rate response time is calculated from the running state of the vehicle, and the start timing of the motion control of the vehicle with respect to the forward curve is determined based on the yaw rate response time. The motion control can be started at an appropriate timing in consideration of the delay, and a high level of stability can be improved. Also, the yaw rate response time is calculated from the running state of the vehicle, the yaw rate response distance is calculated based on the yaw rate response time, and the yaw rate response distance is reflected in the motion control of the vehicle, so that the behavior delay of the vehicle is taken into account. Motion control can be started at an appropriate timing, and a high level of stability can be improved.

[Brief description of the drawings]

1 to 7 show a first embodiment of the present invention, and FIG. 1 is a block diagram showing an overall configuration of a vehicle motion control device.

FIG. 2 is an explanatory diagram of a configuration of a curve shape detection unit.

FIG. 3 is an explanatory diagram of a method of obtaining a curvature radius of a curve.

FIG. 4 is an explanatory diagram of correction of a radius of curvature of a determined curve.

FIG. 5 is an explanatory diagram of an example of point data actually obtained from a navigation device;

FIG. 6 is an explanatory diagram of each case in the data reduction unit.

FIG. 7 is a flowchart of vehicle movement start determination control;

8 and 9 show a second embodiment of the present invention, and FIG. 8 is a block diagram showing an overall configuration of a vehicle motion control device.

FIG. 9 is an explanatory diagram of characteristics of a yaw rate response time correction coefficient and a required yaw rate.

FIG. 10 is a flowchart of a vehicle motion start determination control for a forward curve.

11 to 14 show a third embodiment of the present invention, and FIG. 11 is a block diagram showing an entire configuration of a vehicle motion control device.

FIG. 12 is an explanatory diagram of a control start determination / control unit.

FIG. 13 is a flowchart of vehicle motion start determination control.

FIG. 14 is a flowchart of a subroutine for control start determination.

[Explanation of symbols]

9: braking force control device 10: alarm device 11: yaw rate response time calculation unit (yaw rate response time calculation unit) 12: curve shape detection unit (curve shape detection unit) 13: control start determination / control unit (control start determination /
Control means) 14... Required yaw rate calculating section (necessary yaw rate calculating means)

Claims (6)

[Claims] 1. A vehicle motion control device for detecting a running state of a vehicle and performing at least one of a vehicle behavior control and an alarm control in accordance with the detected running state to control the motion of the vehicle. A yaw rate response time calculating means for calculating a road friction coefficient estimated value based on the calculated road surface friction coefficient and calculating a time until a yaw rate of the vehicle responds when the vehicle is steered based on the estimated road surface friction coefficient and the vehicle speed; Curve shape detecting means for detecting the curve of the vehicle and calculating the distance from the vehicle to the front curve; and calculating the yaw rate response time calculated by the yaw rate response time calculating means and the front curve calculated by the curve shape detecting means. A control start determining / controlling means for determining and controlling the start of the vehicle motion control for the forward curve based on the distance; Motion control device. 2. An allowable lateral acceleration when traveling on the front curve is calculated based on a traveling state of the vehicle and a road surface state, and the allowable lateral acceleration and a curvature radius of the front curve detected by the curve shape detecting means are calculated. A yaw rate calculating means for calculating a yaw rate of the vehicle required when traveling on the front curve based on the yaw rate response time calculating means, based on the road surface friction coefficient estimated value and the vehicle speed. The vehicle motion control device according to claim 1, wherein a value obtained by correcting the yaw rate response time according to the required yaw rate is set as a yaw rate response time. 3. The control start determination / control means calculates a time required for the vehicle to reach the front curve based on the vehicle speed and the distance to the front curve of the vehicle calculated by the curve shape detecting means. 4. The method according to claim 1, further comprising: comparing the time required to reach the forward curve with the yaw rate response time calculated by the yaw rate response time calculation means to determine the start of vehicle motion control. The vehicle motion control device as described in the above. 4. The control start determination / control means calculates a response distance when the vehicle is motion-controlled based on the vehicle speed and the yaw rate response time of the vehicle calculated by the yaw rate response time calculation means. The vehicle according to any one of claims 1 and 2, wherein a start of the vehicle motion control is determined by comparing a response distance and a distance to the front curve of the vehicle calculated by the curve calculation means. Exercise control device. 5. The control start determination / control means calculates a yaw rate response distance when the vehicle is motion-controlled based on the vehicle speed and the yaw rate response time of the vehicle calculated by the yaw rate response time calculation means. The vehicle motion control device according to any one of claims 1 and 2, wherein the start of the vehicle motion control is determined based on the yaw rate response distance. 6. An allowable lateral acceleration when the vehicle travels on the front curve based on a traveling state of the vehicle and a road surface state, and calculates the allowable lateral acceleration and a radius of curvature of the front curve detected by the curve shape detecting means. A required yaw rate calculating means for calculating a required yaw rate of the vehicle in the forward curve, wherein the vehicle behavior control independently applies a braking force to a wheel selected based on a target yaw rate obtained based on a running state of the vehicle. 6. In the case of the braking control in which is added, the required yaw rate is set as a target yaw rate when performing the braking force control. Vehicle motion control device.