JP3293385B2 - Control system for road conditions ahead of automobiles - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a device for detecting a road condition ahead of an automobile in advance and issuing a warning to a driver or controlling the running condition of the vehicle in accordance with the road condition. The present invention relates to a control device for a road condition ahead of a vehicle, which is suitable for use in generating a warning to a driver or controlling the speed of a vehicle immediately before entering a vehicle.

[0002]

2. Description of the Related Art When a vehicle runs on a curved road, the driver must adjust the vehicle speed so that the vehicle speed does not become excessive with respect to the curvature of the curve in order for the vehicle to turn the curve. . By the way, a traction control device has been developed which controls the speed of the vehicle such that the vehicle does not run excessively when traveling in a curve. In this device, the lateral acceleration of the vehicle is estimated from the vehicle speed and the steering wheel angle, and if the lateral acceleration is too large, the engine output is suppressed to limit the speed of the vehicle.

[0003]

By the way, the deceleration operation actually performed by the driver when the vehicle approaches a curved road is not performed after entering the curve but in advance immediately before entering the curve. That is, when the driver recognizes this curved road, it is most desirable to decelerate the vehicle in advance before entering the curve.

[0004] However, the traction control device functions only when the steering wheel is turned during driving.
In other words, this is the case where the vehicle is actually traveling on a curve, and the control is not performed before entering the curve. For this reason, the control by the traction control device at the time of traveling on a curve may give a driver an uncomfortable feeling, and it is not possible to realize optimal curve traveling control.

[0005] Therefore, it is necessary to detect the vehicle before entering the curve. As means for detecting the road condition ahead of the vehicle, use of road map information from a navigation system can be considered. . For example, Japanese Patent Publication No. 6-58141 discloses a technique for controlling a transmission in accordance with the current position of a vehicle obtained from a navigation system. This technique detects, in particular, a road condition ahead of the vehicle. However, it does not control the running of the vehicle in advance.

Further, Japanese Patent Application Laid-Open No. 4-75200 discloses that
A technology has been disclosed in which a region for issuing a warning for vehicle speed is set in road map information obtained from a navigation system, and a warning is issued when a vehicle enters this warning region and the vehicle speed is excessively high. However, the vehicle is not particularly preliminarily driven before entering the required area. JP 4
Japanese Patent Application Laid-Open No. 15799 discloses a technique of performing feedforward control of a throttle opening of an engine of a vehicle and a shift speed change based on a road condition ahead of the vehicle obtained from a navigation system. Further, Japanese Patent Application Laid-Open No.
Japanese Patent No. 6699 discloses a technique for controlling the vehicle speed or notifying the driver of the vehicle speed before the vehicle enters a curved road based on a road condition ahead of the vehicle obtained from a navigation system.

[0007] However, the road information and the vehicle position information from such a navigation system include a considerable error, and the actual curve start position and the curve start position obtained from the navigation system are shifted. Then, there is a problem that it is difficult to issue an alarm or control the running of the vehicle at an accurate timing.

SUMMARY OF THE INVENTION The present invention has been made in view of the above-mentioned problems, and when a vehicle enters a curve, the running state of the vehicle is easily and reliably controlled in advance in accordance with the road conditions ahead of the vehicle. It is an object of the present invention to provide a control device for a road condition ahead of a vehicle, which can alert a driver to that effect and corrects error information from a navigation system to accurately detect a curve. Aim.

[0009]

According to the first aspect of the present invention, there is provided a road condition control apparatus for a vehicle in front of a vehicle, comprising: a curve detecting means for detecting a curve on a road ahead of the vehicle when the curve exists; When a curve is detected by the curve detecting means, when entering the curve, determining means for determining whether or not the current speed of the vehicle is too high; and based on the determination result of the determining means, the speed of the vehicle is determined. When it is determined that the vehicle is too large, an alarm is generated or a non-conforming control unit for controlling the running state of the vehicle is provided. A first point on the road line, which is behind the curve detection point on the road line by a sampling distance, and a second point on the road line, which is ahead by the sampling distance, are determined. A curvature index calculating means for calculating a curvature index at the curve detection point based on an angle between a first vector reaching the point and a second vector extending from the curve detection point to the second point; The curvature index calculated by the index calculation means is compared with a curve determination reference curvature index, and when the curvature index is larger than the curve determination reference curvature index, it is determined that the curve detection point is curved, and Curve determining means for detecting a curve start point on a road line ahead of the vehicle based on the curvature index calculated by the curvature index calculating means, and sampling distance setting for setting the sampling distance according to the radius of curvature of the curve. Means, and the non-conforming control means is configured to generate the above-mentioned alarm or control the traveling state based on the curve start point information detected by the curve determination means. A correction means for correcting the position of the curve start point detected based on the curvature index so as to correspond to the error of the curve start point caused by the setting of the sampling distance. It is characterized by having.

According to a second aspect of the present invention, in addition to the configuration of the first aspect, the correction means may be configured such that the correction means includes a curve having a moderate curve or a moderate curve. It is characterized in that different corrections are made depending on whether a curve has no curve.
According to a third aspect of the present invention, in addition to the configuration of the first aspect, the correction means includes a data table of a correction value corresponding to a preset curve radius. The correction is performed based on

According to a fourth aspect of the present invention, in addition to the configuration of the third aspect, the correction means further comprises a correcting means for adjusting a curve radius which is not set in the data table. When the curve is corrected, the correction value is calculated by first-order complementing the correction value set in the data table.

According to a fifth aspect of the present invention, in addition to the configuration of any of the first to fourth aspects, the curve detecting means is stored in the navigation system. It is configured to detect the curve based on the obtained road information. According to a sixth aspect of the present invention, in addition to the configuration of the first aspect, the traveling state control of the vehicle by the nonconformity control means includes a deceleration control of the vehicle. It is characterized by being.

According to a seventh aspect of the present invention, in addition to the configuration of the sixth aspect, the deceleration control is performed by controlling the output of an engine mounted on the vehicle. It is characterized by being performed. In addition, the control device for road condition in front of a car according to the present invention described in claim 8 is the same as the above-described claim 6 or 7,
The deceleration control is performed by a shift-down control of an automatic transmission mounted on the vehicle.

Further, the front road conditions corresponding control apparatus for an automobile of the present invention of claim 9, wherein, in addition to the above-described configuration according to claim 7, wherein, the deceleration control, when in order to warn of the presence of the curve
It is characterized by being restricted for a while.

[0015]

According to the above-mentioned first aspect of the present invention, if a curve exists on the road ahead of the vehicle, the curve is detected by the curve detecting means. Further, when a curve is detected by the curve detection means, the determination means determines whether or not the current speed of the vehicle is too high when entering the curve. When the nonconforming control unit determines that the speed of the vehicle is too high based on the determination result of the determination unit, an alarm is issued or the running state of the vehicle is controlled.

In the curve detecting means, first, the sampling distance is set by the sampling distance setting means in accordance with the radius of curvature of the curve ahead of the vehicle. Then, the curvature index calculating means calculates a first point on a road line behind the curve detection point on the road line in front of the vehicle by a sampling distance.
A point and a second point on the road line ahead of the curve detection point by a sampling distance are determined, and a first vector from the first point to the curve detection point and a second vector from the curve detection point to the second point are determined. The curvature index at the curve detection point is calculated based on the angle between the two vectors.

Next, the curve judgment means compares the curvature index with the curve judgment reference curvature index based on the curvature index calculated by the curvature index calculation means, and determines the curvature index from the curve judgment reference curvature index. Is larger, it is determined that the curve detection point is curved. Further, a curve start point on a road line ahead of the vehicle is detected based on the curvature index calculated by the curvature index calculation means. Note that the error of the curve start point caused by the setting of the sampling distance is corrected based on the curvature index by the correction means provided in the curve determination means. Then, based on the curve start point information detected by the curve determination means, the non-conformity control means generates an alarm or controls the running state.

In the control device according to the second aspect of the present invention, different corrections are made by the correction means depending on whether the curve has a transition curve or a transition curve-free curve. According to a third aspect of the present invention, the above correction is performed by the correction means based on a data table of correction values corresponding to a preset curve radius.

According to the fourth aspect of the present invention, when a curve having a curve radius not set in the data table is corrected, the correction set in the data table is performed by the correction means. A correction value is calculated by first-order complementing the value. In the control device according to the fifth aspect of the present invention, the curve detecting means detects a curve based on the road information stored in the navigation system.

In the control device according to the sixth aspect of the present invention, if the traveling state of the vehicle is determined to be incompatible with the guidance route state in front of the vehicle by the determination means, the vehicle becomes incompatible. Time control means generates an alarm or controls deceleration of the vehicle. According to a seventh aspect of the present invention, the deceleration control is performed by controlling the output of an engine mounted on the vehicle.

In the control device according to the present invention, the control is performed by downshift control of an automatic transmission mounted on the vehicle. According to a ninth aspect of the present invention, the deceleration control is time-limited to warn of the presence of the curve.
That therefore, the driver can recognize the existence of the curve by the speed reduction control and said alarm. In addition, this deceleration control is time-based.
Because it is limited, not this deceleration from those excessive, steamed
The main effect is the warning effect to the driver rather than the speed reduction effect of the vehicle speed
It becomes something.

[0022]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 to FIG. 37 show a control device for a road ahead of a vehicle as an embodiment of the present invention. 1. Overall Configuration The control device for a road condition ahead of a vehicle uses a vehicle navigation system 50 as shown in FIG. 2 and a traction control system (hereinafter referred to as a trace control system) 70 for trace control as shown in FIG. It is configured to be.

That is, the present apparatus detects a curve (curve road) on the road ahead of the vehicle based on the road map information ahead of the vehicle obtained from the navigation system 50, and detects the detected curve information and vehicle speed information. When it is determined that the traveling speed of the vehicle is too large for the vehicle to travel along this curve based on the vehicle speed-related lateral acceleration information used in the trace control system 70, the generation of an alarm and the control of the traveling state of the vehicle are performed. It is supposed to do it.

For this reason, as shown in FIG. 1, the present apparatus includes a curve detecting means 20 for detecting a curve, a judging means 30 for judging the running speed of the vehicle with respect to the curve, When it is determined that the curve is too large to bend the curve (in case of non-conformity), an alarm is generated indicating that the curve exists ahead of the curve or the speed is too high for the curve, or the running state of the vehicle is not controlled. An hour control means 40 is provided.

The curve detecting means 20 uses the road map information of the optimum route obtained during the route guidance of the navigation system 50, and the judging means 30 uses the lateral acceleration characteristics used in the trace control system 70. ing. As the navigation system 50 and the trace control system 70, those of a known technology can be used. Before describing the details of the present control device, a brief description will be given of the navigation system 50 and the related devices such as the trace control system 70. 2. Related Devices 2.1 Navigation System The navigation system 50 includes, as shown in FIG.
Road map information storage means 52 such as a CD-ROM for storing road map information, an input switch (data input means) 54 for inputting a destination and a current position of the vehicle, and a current position estimating means for estimating the current position of the vehicle 56, an optimal route selection and storage unit 58 for selecting and storing an optimal route from the current position to the destination, a screen information control unit 60 for controlling screen display information of map information and optimal route information, and navigation. A navigation voice control means 62 for controlling voice information is provided. Current position estimating means 56,
Optimal route selection / storage means 58, screen information control means 60,
The navigation voice control means 62 is configured using a microcomputer.

The current position estimating means 56 is a so-called GPS
The current position is estimated while correcting by the map matching method to the position estimation by the navigation and the autonomous navigation. That is, radio waves transmitted from a plurality of (three or more) artificial satellites [GPS (Global Position)]
While the current position of the vehicle is estimated by the GPS navigation while obtaining the [Ning System] information through the GPS receiver 82, the traveling route of the vehicle is accumulated based on the information from the vehicle speed sensor 84, the geomagnetic sensor 86, and the gyro compass 88. The current position of the vehicle is estimated by autonomous navigation. Then, for the position estimation by the GPS navigation and the autonomous navigation, the current position is finally estimated by the map matching method using the road map information from the road map information storage means 52.

Road map information storage means (CD-ROM) 5
2, road map information is stored at each of a plurality of hierarchical levels having different scales. In addition, road type information such as expressways, general national roads, and local roads, and information such as traffic conditions related to intersections are also stored. It is remembered. The road data in the road map information includes point data input at predetermined intervals (for example, 10 m pitch) and line data formed by continuously connecting these points. In particular,
The point data is used as a curve detection point used for curve detection described later.

The optimum route selection / storage means 58 selects an optimum road between the current position of the vehicle and the destination based on the road map information from the road map information storage means 52, and stores this road information in image information. To be stored. Screen display control means 6
In the case of 0, the map information from the map information storage means 52, the optimum route information from the optimum route selection / storage means 58, and the current position information from the current position estimation means 56 are processed, and the display 90 includes the current position. The map information and the optimal route information are displayed on the screen.

In the navigation voice control means 62, together with the screen display control means 60, the map information from the map information storage means 52, the optimum route information from the optimum route selection / storage means 58, and the current position from the current position estimation means 56. Based on the information, voice information related to navigation such as a course change is selected, and necessary voice information is generated, for example, through voice information generating means 92 using an audio system. 2.2 Trace Control System As shown in FIG. 3, the trace control system 70 includes a target lateral acceleration calculating means 72 for calculating a target lateral acceleration Gy _th of a vehicle turning a curve, a target lateral acceleration calculating means 72, and driving characteristics described later. a target longitudinal acceleration setting means 74 for setting a target longitudinal acceleration Gx _th based on information from the estimating means 78, a torque converting means 76A for converting the target longitudinal acceleration Gx _th engine torque, constant conversion torque limit And a target throttle opening degree setting means 76C for setting a target throttle opening degree of the engine according to the clipped engine torque. Then, the trace control system 70 includes a traction control switch 71
Fires when is set to the input state. Although not shown, the traction control lamp is turned on when the trace control system 70 is started.

The target lateral acceleration calculating means 72 calculates the target lateral acceleration Gy _th by the following equation based on the detection information from the steering angle sensor 80 and the vehicle speed sensor 84. Gy _th = δ / [ω · {A + ( 1 / VB ² )}] where δ is the steering angle, VB is the vehicle speed (vehicle speed), ω is the wheelbase of the vehicle, and A is the characteristics of the suspension and tires and the road surface conditions. The stability factor of the vehicle is determined by the above factors.

The target longitudinal acceleration setting means 74 calculates the target lateral acceleration Gy based on a map as shown in FIG.
_th, which is the vehicle speed VB and driver's driving characteristics (quickness degrees) to set the target longitudinal acceleration Gx _th.
With such target longitudinal acceleration Gx _th is determined, the target longitudinal acceleration Gx _th torque conversion means 76A in terms of engine torque, further, after clipping a torque within a certain limit in clipping means 76B, the target throttle opening The degree setting means 76C sets a target throttle opening degree according to the engine torque.

[0032] Therefore, when the steering operation during turns the curve is performed, the throttle opening of the engine is controlled through a throttle driving means 94, the travel of the vehicle is controlled in turning such that the target lateral acceleration Gy _th It is. 2.3 Estimation of driving characteristics
I want to reflect the driver's preference. Since the driver's preference appears as the characteristics of the driving performed by the driver, the driving characteristics suitable for each driver are realized by estimating the driving characteristics of the driver and reflecting the characteristics in the driving control of the automobile.

Here, the driving characteristics of the driver are defined as follows. In other words, the driver prefers, for example, traveling at a relatively constant speed with gentle acceleration and deceleration (such traveling is referred to as “relaxing traveling”), or traveling at a relatively high speed with a rapid acceleration and deceleration. The degree of loose running or the degree of crisp running, such as whether the user prefers such running (referred to as “crisp running”), is taken as the driving characteristic of the driver. Such driving characteristics can be estimated based on physical quantities representing the driving state of the vehicle.

However, since the driving characteristics of the driver change according to the road traffic conditions in which the vehicle travels, the driving characteristics estimating means 78 estimates the driver's traffic conditions while estimating the road traffic conditions by the road traffic condition estimating means 78A. Driving characteristics,
The estimation is performed based on the road traffic condition and the physical quantity representing the driving state of the vehicle. (A) Estimation of Road Traffic Condition The road traffic condition estimation means 78A calculates the road traffic condition in FIG.
Estimate as shown in

That is, the vehicle speed VB and the steering wheel angle (steering angle)
From δ, a running time ratio, an average speed, and an average lateral acceleration are obtained as parameters of the vehicle running state. this house,
The average speed and the average lateral acceleration are general values and are calculated by a known method. On the other hand, the running time ratio is the ratio of the running time Td to the total time Tall (= Td + Ts) obtained by adding the running time Td and the stop time Ts of the vehicle [= Td / (Td + Ts)]. If the vehicle speed VB is lower than a predetermined value (for example, 10 km / h), the stop time Ts is counted, and if the vehicle speed VB is higher than a predetermined value (for example, 10 km / h), the running time Ts is counted and calculated.

Then, based on the running time ratio, the average speed, and the average lateral acceleration, the degree of urban area, the degree of congested road, and the degree of mountainous road are estimated. These estimates use fuzzy inference. For example, in the case of an urban area, the average speed is low and the traveling time ratio is medium,
In the case of a congested road, there is a feature that the average speed is low and the running time ratio is low. In the case of a mountain road, there is a feature that the running time ratio is high and the integral value of the lateral acceleration is high. By setting a membership function and a fuzzy rule based on such features, it is possible to estimate a city area degree, a congestion road degree, and a mountain road degree, respectively. (A) Estimation of Driving Characteristics The driving characteristic estimating means 78 obtains the road traffic conditions and the physical quantities representing the driving conditions of the vehicle (ie, accelerator opening, vehicle speed, longitudinal acceleration which can be calculated from the vehicle speed, vehicle speed and steering wheel angle). The driving characteristics of the driver are estimated, as shown in FIG.

That is, first, a frequency analysis is performed on each of the physical quantities (accelerator opening, vehicle speed, longitudinal acceleration, lateral acceleration) representing the driving state of the vehicle by a known statistical method, and the average value and variance of each physical quantity are determined. calculate. And
Based on the average value and variance of each of these physical quantities, and the average value and variance of each physical quantity that is characterized for each road condition, based on the estimated urban area, congested road, and road traffic conditions of mountainous roads. The driving characteristics of the driver can be estimated from the correspondence with the driving characteristics of the driver.

Here, a neural network is used for estimating the driving characteristics. That is, the average and variance of each physical quantity increase as the driving of the driver becomes crisp, and the average and variance of each physical quantity decrease as the driving of the driver decreases. Of course, this is evaluated on a different scale for each road condition, but the neural network is designed so that the association between the average value and variance of each physical quantity according to each road condition and the driving characteristics of the driver is used as an associative model. Has formed.

Then, the average value and variance of each physical quantity and the road traffic conditions such as the urban area level, the congested road level, and the mountain road level are input to this neural network to obtain the driving characteristics (slowness or crispness) of the driver. Like that.
Of course, the estimation of the driving characteristics is performed while always inputting the latest data as each physical quantity and road traffic condition, and even when the driving characteristics of the driver change, the estimation can be performed in accordance with this. I can do it. Therefore, the degree of looseness or crispness obtained by the driving characteristic estimating means is obtained by appropriately estimating the characteristics of the driver actually driving. 3. Explanation of each part of this device Next, each part of the road condition control device 10 of the vehicle will be described by dividing it into a part related to curve detection, a part related to vehicle speed determination, and a part related to nonconforming control. . 3.1 Curve Detection The curve detecting means 20 extracts necessary information from the navigation system 50 and detects the state of a curve ahead of the vehicle.

Here, the curve detecting means 20 recognizes a curve satisfying the following two conditions as a curve to be detected, based on the map information of the navigation system 50 and the running state of the vehicle. The curve radius R must be small within a certain range [for example,
The curve radius R is equal to or less than a predetermined value (for example, 200 m)].

The curve is a curve with poor visibility. The condition is, for example, that the curve radius R of the highway is at least 2
Such a gentle curve with a radius R of about 50 m or more, which is equal to or larger than a predetermined value, is set in consideration that the risk is low and the necessity of alarm control is low even when entering at a relatively high speed. That is, it is based on the idea that the warning and the control are performed only when the degree of necessity is high, so that the driver is not discomforted and the control effect is enhanced.

The reason is that a curve with good visibility is considered to have low risk. Note that the curve satisfying these conditions, that is, the curve to be detected is a region indicated by hatching in FIG.
/ S ² in the calculation) and a. Note that the curve detection means 20 detects the angle θ shown in FIG. 9 as a curve angle.

Hereinafter, the curve detecting means 20 will be described in detail. As shown in FIG.
0 includes sampling distance setting means 21, curvature index calculating means 22, curve determining means 23, blind curve detecting means 24, control target curve selecting means 25, continuous curve determining means 26, hairpin curve detecting means 27, and the like. I have. (1) Principle of Curve Detection As shown in FIG. 10, the curvature index calculating means 22 calculates, for example, a point B on the road line RL in front of the vehicle (this is set as a curve detection point) by a sampling distance L behind. Given a point (point A) and a second point (point C) ahead of the curve detection point (point B) by a sampling distance L, a first vector AB from point A to point B; From point B to point C
Is calculated as a curvature index at the point B with respect to the second vector BC.

The curve radius R is calculated from the sampling distance L and the curvature index θ according to the following equation. R = L / [2 · sin (θ / 2)] That is, the value of the curvature index θ is an index representing the degree of curvature of the curve at the point B, and the larger the curvature index θ, the more the point B
Indicates that the radius of curvature R of the curve is small and the curve is steep.

Then, the curve judgment means 23 compares the curvature index θ calculated by the curvature index calculation means with a curve judgment reference curvature index θ _O (θ _O > 0) as a curve judgment threshold value. If θ | ≧ θ _O , it is determined that the point B is curved. And conversely |
If θ | <θ _O , it is determined that the road is straight.

When the curvature index θ is positive, the direction of the curve is clockwise (right curve), and the curvature index θ
Is negative, it indicates that it is counterclockwise (left curve). By providing detection points such as the point B on the road line RL ahead of the vehicle at appropriate intervals, the curvature index θ
, The characteristic of the road shape, that is, the change in the curvature of the curve or the like can be extracted.

Also, in the case of the present apparatus, the curve detection point is located 10 m on the road line RL so that point data (input at a 10 m pitch) in the road map information selected at the time of route guidance can be used. The pitch is set, and the sampling distance L is also set to an integral multiple of this pitch interval. For example, as a point for obtaining a curvature index corresponding to the points A and C, a curve detection point behind or in front of the curve detection point is used. Therefore, the curvature index θ is calculated every 10 m on the road line RL.

In the curve determining means 23, the curvature index θ of the detection points arranged on the road line RL is determined by the curve determination reference curvature index θ.
Against _O | θ | <θ from _O state | theta | becomes a ≧ theta _O, the curve detection point of time and the curve starting point LS,
It is determined that the curve has started from the curve start point LS. On the contrary, when the curvature index θ is |
theta | from the state of ≧ θ _O | θ | <becomes a theta _O, the curve determining means 23, which is a curve detection point of time to be determined curve end point LE.

Then, the curve determining means 23 determines the area between the curve start point LS and the curve end point LE as a curve, and informs that there is a curve, the information indicating that the curve exists, the curve start point LS and the curve end point LE. , Curve start point LS
The minimum value of the curve radius R from the curve to the curve end point LE is output as a curve radius representing this curve. (2) Sampling distance setting The sampling distance setting means 21 is a curvature index calculating means 2
The sampling distance L used in step 2 is set based on the radius R of the curve. That is, as shown in FIG. 10, the curve detecting means 20 basically has a length L of 2
The bending degree of the curve is calculated from the angle of the straight line.
At this time, the length (sampling distance) L of the straight line is set according to the curve radius R.

The sampling distance L is selected, for example, from a plurality of distance data stored in advance in the sampling distance setting means in accordance with the curve radius R. The sampling distance L = L _min ( R <100
m), the sampling distance L = L _mid (100 m ≦
R = 200m), sampling distance L = L
_The sampling distance L is selected from three types of distance data of _max (when R> 200 m) (L
_min <L _mid <L _max ).

The radius of curvature R at each curve detection point is
Is calculated by the above-described equation. However, since the radius of curvature R of the target detection point cannot be found unless the sampling distance L is determined, in the present embodiment, the radius of curvature R can be calculated in advance of the target detection point. The curve radius R is used. At the start of curve detection, the sampling distance L is initially set to a maximum value _Lmax , and thereafter, the sampling distance L is updated anew according to the calculated value of the curve radius R. (3) Correction of Curve Start Point LS As described above, the sampling distance L is set according to the radius of the curve. The magnitude of the judgment reference curvature index θ _O is also changed.

For example, the sampling distance L = L _min , L
_{When mid} , the curve determination reference curvature index θ _O = θ ₂ is set, and when L = L _max , θ _O = θ ₁ is set (θ ₂ > θ ₁ ). Further, as shown in FIG. 11, it is conceivable that the curve start point detected by the above-described curve determination means 23 does not always coincide with the actual curve start point.

This is because the curvature index θ is calculated from the angle between the two straight lines, and furthermore, the length of these two straight lines is set to a relatively large sampling distance L (here, L _min , L _mid , or L _max ). Further, the magnitude of the set value (here, θ ₂ or θ ₁ ) of the curve judgment reference curvature index θ _O also has an effect.

As a result, as shown in FIG. 11, it is conceivable that the curve start point is detected on the near side of the actual curve start point. Therefore, the curve determining means 2
3 is provided with a correction means 23A for correcting the position of the curve start point so as to correspond to the error of the curve start point caused by the setting of the sampling distance L. a. In the case of a curve without a transition curve In the case of a curve without a transition curve as shown in FIG. 11, the correction means 23A calculates the correction value of the error at the curve start point as follows. Note that FIG.
Is the linear distance between the actual curve start point (point P) and the point C when the curvature index θ = θ ₀ .

When the curve radius R is 20 m (sampling distance L = L _min , curve judgment reference curvature index θ _O = θ
₂ ). When the curvature index θ = θ ₂ , a ₁ (= sampling distance L _min −) is larger than the actual curve start point (point P).
This means that the curve start point (point B) is detected before the distance e).

Therefore, the distance a ₁ (for example, 23 m)
Was a correction value, the actual curve starting point than the curve starting point (point B) (point P) is to determined to be a ₁ forward. Curve radius R = 30 m (sampling distance L =
L _min , curve judgment reference curvature index θ _O = θ ₂ ). When the curvature index θ = θ ₂ , the correction value is a ₂ (for example, 19
m). And, thereby, the actual curve starting point (point P) is determined to be a ₂ forward relative to the curve starting point (point B).

When the curve radius R is 50 m (sampling distance L = L _min , curve judgment reference curvature index θ _O = θ
₂ ). When the curvature index θ = θ ₂ , the correction value is a
₃ (for example, 13 m). Thus, the actual curve starting point (point P), it is determined that a ₃ is a front against the curve starting point (point B).

When the curve radius R is 70 m (sampling distance L = L _min , curve judgment reference curvature index θ _O = θ
₂ ). When the curvature index θ = θ ₂ , the correction value is a
₄ (for example, 8 m). Thus, the actual curve starting point (point P) is determined to be a ₄ forward with respect to the curve starting point (point B).

When the curve radius R is 100 m (sampling distance L = L _mid , curve judgment reference curvature index θ _O =
θ ₂ ). When the curvature index θ = θ ₂ , the correction value is a ₅
(For example, 26 m). Thus, the actual curve starting point (point P) is determined to be a ₅ forwardly relative to the curve starting point (point B).

When the curve radius R is 150 m (sampling distance L = L _mid , curve judgment reference curvature index θ _O =
θ ₂ ). When the curvature index θ = θ ₂ , the correction value is a ₆
(For example, 14 m). Thus, the actual curve starting point (point P) is determined to be a ₆ forward with respect to the curve starting point (point B).

When the curve radius R is 200 m (sampling distance L = L _mid , curve judgment reference curvature index θ _O =
θ ₂ ). When the curvature index θ = θ ₂ , the correction value is a ₇
(For example, 4 m). Thus, the actual curve starting point (point P), it is determined that a ₇ is a front against the curve starting point (point B).

The correction means 23A sets the correction amount based on the magnitude of the curve radius R according to the error calculated as described above.
The correction values at the respective curve radii R are input to the correction unit 23A as a data table as shown in FIG. In the case of a curve radius R other than those described above, the correction value is calculated by performing primary interpolation from the above data. b. When there is a transition curve On the other hand, in the case of a curve having a transition curve as shown in FIG. 12, the correction means 23A calculates the correction amount as follows.

Here, the relaxation curve means that at any point on the curve, the product of the distance from the start point (point P) of the curve to the above-mentioned arbitrary point and the radius of curvature at the above-mentioned arbitrary point is always constant. It is a curve having such properties. Then, assuming that the length of the relaxation curve is L ₁ and the radius of the curve is R, the amount of change of this relaxation curve in the y direction (S shown in FIG. 12) can be calculated by the following equation. S = L ₁ ² / 24R Therefore, when calculating by substituting the 20~200m the curve radius R of this formula, S is fit into the range even of the order of 0.5m in maximum point B (relaxation curve shown in FIG. 12 (Upper point) can be regarded as being on an extension of the straight line AP.

As a result, when the correction amount corresponding to the curve radius R is obtained, the following is obtained. Curve radius R = 20 m (relaxation curve distance L ₁ = d
₁ , sampling distance L = L _min ). Curvature index θ = θ ₀
Then, the distance e from the actual curve start point (point P) to the curve start point (point B) detected by the curve detecting means 20 is b ₁ (for example, 12 m), which is the actual curve start point (point This means that the curve start point (point B) is detected b ₁ before point P). Thus the correction amount is b _1.

When the curve radius is R = 30 m (relaxation curve distance L ₁ = d ₂ , sampling distance L = L _min ). When the curvature index θ = θ ₀ , the actual curve start point (point P)
Curve start point (point B) before b ₂ (for example, 7 m)
Has been detected, so that the correction amount is b
It becomes ₂ .

When the curve radius is R = 50 m (relaxation curve distance L ₁ = d ₃ , sampling distance L = L _min ). When the curvature index θ = θ ₀ , the actual curve start point (point P)
Curve start point (point B) ahead of b ₃ (for example, 4 m)
Is detected, and the correction amount is b ₃ (b ₃ = −4 in this case)
m).

When the curve radius is R = 70 m (relaxation curve distance L ₁ = d ₄ , sampling distance L = L _min ). When the curvature index θ = θ ₀ , the actual curve start point (point P)
The curve start point (point B) is detected ahead of b ₄ (for example, 12 m), and the correction amount is b ₄ (in this case, b ₄ =
−12 m).

When the curve radius is R = 100 m (relaxation curve distance L ₁ = d ₅ , sampling distance L = L _mid ). When the curvature index θ = θ ₀ , the curve start point (point B) is detected b ₅ (for example, 2 m) before the actual curve start point (point P), and therefore, the correction amount is b ₅ Become.

When the curve radius is R = 150 m (relaxation curve distance L ₁ = d ₆ , sampling distance L = L _mid ). When the curvature index θ = θ ₀ , the curve start point (point B) is detected b ₆ (for example, 13 m) ahead of the actual curve start point (point P), and the correction amount is b ₆ (= − 13
m).

When the curve radius is R = 200 m (relaxation curve distance L ₁ = 50 m, sampling distance L = L _mid ).
When the curvature index θ = θ ₀ , the curve start point (point B) is detected b ₇ (for example, 30 m) ahead of the actual curve start point (point P), and the correction amount is b ₇ (= − 30
m).

In the case of a curve having a relaxation curve, the correction means 23A sets a correction amount in accordance with the above calculation result. In addition, each correction value at each curve radius R described above is:
The correction means 23 is used as a data table as shown in FIG.
In the case of a curve radius R other than the above, the correction value is calculated by performing primary interpolation from the above data. This makes it possible to easily and quickly correct a curve having a curve radius not set in the data table.

As described above, the correction of the curve start point LS is
By providing the correction means 23A with a data table of correction values corresponding to the preset curve radius R, the curve start point LS can be corrected by the correction means 23A, and the curve start point LS can be detected more accurately. In addition, by performing different correction depending on whether the detected curve is a curve having a transition curve or a curve having no transition curve, it is possible to perform the correction according to the road curve situation.

Further, by setting the correction value for each curve radius R in advance and inputting it as a data table in the correction means 23A, the correction value can be calculated easily and in a short time. is there. In general, since there is a relaxation curve at the curve connection portion, the correction processing is performed using the data table shown in FIG.

By correcting the curve start point LS, it is possible to accurately detect the curve situation ahead of the vehicle without requiring enormous calculations, and to appropriately perform alarms and vehicle speed control at accurate timing. You can do it. By the way, the correction means 23A for the above-mentioned curve start point or the like makes only a typical correction value of the curve radius into a data table, and for curves having other curve radii, performs a primary interpolation from the above data table to perform correction. The value is calculated. For example, a correction value corresponding to each change of the curve radius by 1 m is prepared, and such a segmented data table may be stored in the correction unit 23A. Good. The correction means 23A also performs correction on the curve end point LE in the same manner. (4) Detection of Blind Curve Next, the detection of the blind curve will be described. In the curve detecting means 20, the curve radius R is equal to or less than a predetermined value.
A curve that satisfies the two conditions that the visibility of the curve is not good is set as a control target curve. The condition is that a curvature index θ ₀ as a threshold value of a curve determination criterion is set to a predetermined value (here, a theta ₁ or theta ₂ is determined to either the sampling distance L in)
Is automatically satisfied.

On the other hand, the conditions are as follows at the stage of curve determination:
Since it is not judged, it is necessary to consider separately. Therefore, the curve detecting means 20 is provided with a blind curve determining means 24 for determining a blind curve. That is, the blind curve determination means 24 determines whether or not the curve is a blind curve that cannot be seen when entering the curve. Based on the information from the blind curve determination means 24, the detected curve is determined by the blind curve determination means 24. This detection curve is adopted as the control target curve only when it is determined that

This is because the driver often does not feel the necessity of warning or speed control for a curve with good visibility. This is because they often feel annoying. Therefore, the blind curve determination means 24 determines whether the curve is a blind curve or a good-looking curve in the following manner. That is, as shown in FIG. 15, at a position deeper than the range of the curve (curve depth) seen from the vehicle at the curve start position,
If the curve is continued, this is determined as a blind curve.

Here, when the curve depth is represented by using the angle θB in FIG. 15, the curve depth θB is obtained from the distance M from the driver's viewpoint to the road side, the road width LB and the curve radius R by the following equation. It can be calculated geometrically. θB = θB1 + θB2 = cos ^-1 [R / (R + LB)] + cos ^-1 [R / (R + M)] On the other hand, the actual angle θR of the curve shown in FIG. It can be calculated based on the curve end point position information. Here, assuming that the curve start point is LS and the curve end point is LE
Let LE-LS be the length of the curve (ie, the arc length of the curve)
The actual curve angle θR is calculated by the following equation. .theta.R = (LE -LS) / R Then, the curve depth .theta.R is compared with the actual curve angle .theta.R, and the actual curve angle .theta.R is the curve depth .theta.R.
When it is larger than B, this curve is detected as a blind curve.

As can be seen from the above equation, assuming that the distance M and the road width LB are certain values, the curve depth θ
B is determined according to the curve radius R. Therefore, the blind curve determination means 24 sets the distance M to 6 m and the road width LB
Is assumed to be 3 m, and the curve in the hatched area obtained as shown in FIG. 16 is determined as a blind curve.

As described above, the blind curve judging means 24 judges the curve as a blind curve when the curve continues even in a region in front of the driver which is not actually seen by the driver at the start of the curve. There is an advantage that the determination of the curve becomes very close to the driver's feeling. Further, it is considered that the road information and the vehicle position information by the navigation system 50 include a considerable error, but as shown in FIG. 17, the curve depth obtained from the information from the navigation system 50 is true. Curve depth (actual curve depth)
Of about 80% or more, and it has been experimentally confirmed that there is no practical problem. (5) Selection of Curve to be Controlled Next, the selection of the curve to be controlled will be described. The curve to be controlled selecting means 25 selects only the curve recognized as a blind curve by the blind curve determining means 24 as the curve to be controlled. I do. That is, the condition of the control target curve is included in the curve condition that the curve judgment reference curvature index θ _O is θ ₁ , θ ₂ ,
Here, conditions are given.

The curve recognized as not a blind curve by the blind curve determination means 24 is a curve with good visibility and does not need to be controlled.
The curve is excluded from the curve to be controlled. (6) Detection of Continuous Curve The curve detecting means 20 is provided with a continuous curve determining means 26 for determining whether the curve is a single curve or a continuous curve.
In the warning means 44 provided in the
Based on the determination information from No. 6, different alarms are issued depending on whether the curve is a single curve or a continuous curve.

When the first curve and the second curve exist from the side closer to the vehicle on the road ahead of the vehicle, the continuous curve determination means 26 determines the distance between the first and second curves. If the set value is equal to or more than the set value, the first curve and the second curve are determined to be independent curves, respectively. If the distance between the first and second curves is smaller than the set value, there is a continuous curve. The judgment is made.

The method of determining a continuous curve will be described. As shown in FIG. 18, first, the n-th curve start point is L _1n and the n-th curve end point is L _2n . Specifically, the first curve start point and the first curve end point are represented by L ₁₁ , L ₂₁
, And the start point and end point of the second curve are set as L ₁₂ and L ₂₂ , and the start point and end point of the third and subsequent curves are similarly set as L ₁₃ , L ₂₃ .

Next, the distance D between the curves (the distance between the curves, or simply referred to as distance) D is calculated from the information on the start point of each curve and the information on the end point of each curve. For example, to represent the distance between the first curve and the second curve in D _12, the distance D ₁₂ is geometric from the position information of the second curve starting point L ₁₂ and the first curve end point L ₂₁ In this case, this calculation formula is calculated as D ₁₂
= Expressed as L ₁₂ -L _21.

Then, the distance D ₁₂ between the first curve and the second curve is compared with the threshold value D _0, and the distance D ₁₂ is set to the threshold value D _0.
If it is smaller (D ₁₂ <D ₀ ), it is determined that the first curve and the second curve are continuous curves. The distance D ₁₂ is the threshold value D ₀ or more (D ₁₂ ≧ D
_In the case of ₀ ), since the first curve and the second curve are sufficiently separated, the first curve is determined to be a single curve.

Similarly, the distance D ₂₃ between the second curve and the third curve, the distance D ₃₄ between the third curve and the fourth curve, and the like are sequentially calculated, and the continuous curve continues. Can be detected as well. The threshold value D ₀ is set to, for example, 100 m. As a result, if there is a continuous curve ahead of the vehicle, the driver can know this, and can take appropriate measures against the curve. Further, the alarm unit 44 issues different alarms depending on whether the curve detected based on the determination information from the continuous curve determination unit 26 is a single curve or a continuous curve, so that the driver can move forward. Whether the curve of the road is a continuous curve or a single curve can be specifically known, and an appropriate operation can be performed on the curve.

When the warning means 44 generates a voice warning and detects a continuous curve, the content of the voice warning is set so as to be able to transmit the continuous curve. The user can clearly recognize whether the curve is a continuous curve or a single curve, and can prepare for the operation of the vehicle with a margin. Furthermore, the continuous curve determining unit 26, since not determined by comparing with the threshold D ₀ distance D between the curves or curve of the road ahead is a continuous curve of the or singly curved as to the determination of the continuous curve There is an advantage that it can be performed reliably.

The continuous curve determining means 26 detects a large number (for example, four) of curves ahead of the vehicle and determines whether each curve is continuous.
Only two curves, a first curve and a second curve, are always detected from the near side in front of the vehicle.
It may be determined whether two curves are continuous or independent.

By determining only the two curves, the first curve and the second curve, the time required for the detection can be reduced, and the power consumed by the present apparatus can be reduced. There is an advantage that labor can be saved. (7) Detection of Hairpin Curve Next, the detection of the hairpin curve will be described. The hairpin curve detection means 20 is provided with a hairpin curve detection means 27, and the hairpin curve detection means 27 calculates an actual value calculated by the following equation. If the curve angle θR is equal to or larger than a predetermined value (for example, 130 °), this curve is determined as a hairpin curve. θR = [(LE−LS) / R] · (180 ° / π) where LS is the curve start point, LE is the curve end point, and LE−LS is the curve length (ie, the arc length of the curve). This is an arithmetic expression to be calculated.

The information of the hairpin curve detected by the hairpin curve detection means 27 is output to the alarm means 44. 3.2 Vehicle Speed Determination The determining means 30 for determining the vehicle speed includes an allowable approach lateral acceleration (also referred to as a lateral acceleration threshold) serving as a determination reference value (threshold).
Permissible approach lateral acceleration setting unit 3 for determining Gy ^* according to vehicle speed
2, an expected lateral acceleration calculator 34 for calculating an expected lateral acceleration Gypre that would be generated when the vehicle enters the vehicle at the current vehicle speed VB with respect to the detected radius R of the curve, an allowable approach lateral acceleration Gy ^* , Expected lateral acceleration Gypre (G
and a vehicle speed determination unit 36 for determining whether the current vehicle speed VB is too high. (1) In the allowed program ingress lateral acceleration allowable approach lateral acceleration setting unit 32, a vehicle speed of the target longitudinal acceleration Gx _th in the map as shown in FIG. 4 for use in the trace control system 70 0 - lateral acceleration corresponding curve L1 By using this, an allowable approach lateral acceleration Gy ^* corresponding to the vehicle speed VB is set.

Gx _th = 0 vehicle speed-lateral acceleration correspondence curve L1
Is as shown by a broken line in FIG. 19, the target lateral acceleration value Gy _th trace control the vehicle speed VB is increased there is a drop characteristics. This is because at higher speeds, the load on the tire in the driving direction (front-back direction) increases, and the limit value against the lateral acceleration of the tire decreases.
It is decreasing y _th . Here, the constant value Gy1 is set at a low speed, and the constant value Gy2 (Gy1) is set at a high speed.
> Gy2).

The allowable approach lateral acceleration Gy ^* is given to the target lateral acceleration value Gy _th (Gx _th = 0) having such characteristics as shown in the following equation. Gy ^* = Gy _th -K1 (However, 0 ≦ K1 ≦ 2) the correction coefficient K1, as shown in FIG. 19, constant value so as to decrease a predetermined amount than the target lateral acceleration value Gy _th in the low-speed range (e.g., K1 = 1) and then, a 0 to be equal to the target lateral acceleration value Gy _th in high-speed range, the mid-speed range, the allowable approach lateral acceleration Gy ^* and linear the allowable approach lateral acceleration Gy ^* and high speed range of the low-speed range Give to contact.

This is such that the vehicle enters a curve particularly in a low speed region in a lateral acceleration state which has more room than the trace control. When the allowable approach lateral acceleration Gy ^* is determined as described above, the allowable approach speed V ^* is also determined according to the following equation in accordance with the curve radius R. V ^* = (R · Gy ^* ) ^1/2 (2) Calculation of expected lateral acceleration In the expected lateral acceleration calculation unit 34, the expected lateral acceleration Gypre is detected by the curve radius R detected by the curve detecting means and the vehicle speed sensor 84. The vehicle speed VB is calculated from the following equation.

Gypre = VB ² / R (3) Vehicle speed determination In the vehicle speed determination unit 36, the allowable approach lateral acceleration Gy ^* and the expected lateral acceleration Gypre obtained from the allowable approach lateral acceleration setting unit 32 and the expected lateral acceleration calculation unit 34 are obtained. Compare with
If the following equation holds, it is determined that the current vehicle speed VB is too high to enter the curve ahead.

Gypre> Gy^* The expected lateral acceleration Gypre is equal to the allowable approach lateral acceleration Gy.
^*If the current vehicle speed VB is too high
Is the allowable lateral acceleration G of the expected lateral acceleration Gypre.
y^*The excess level (excess speed level)
It has become. For example, if the threshold is Gy^*1, Gy^*Two
(However, Gy^*1 = Gy^*+ G1, Gy ^*2 = Gy^*
+ G2, 0 <g1 <g2), the overspeed level
As follows: small excess (level 1), medium excess (level 1)
2), can be classified into three stages of large excess (level 3)
it can.

Gy ^* <Gypre ≦ Gy ^* 1 (Level 1) Gy ^* 1 <Gypre ≦ Gy ^* 2 (Level 2) Gy ^* 2 <Gypre (Level 3) The result of such a classification determination can be used for a warning or vehicle speed control described later.

By the way, regarding the vehicle speed judgment, the vehicle speed VB
^May be directly compared with the above-mentioned allowable approach speed V ^* . That is, if the following equation holds, it may be determined that the vehicle speed VB is too high. VB> V ^{* In} this case, when the vehicle speed VB is higher than the allowable approach speed V ^* (when the current vehicle speed VB is too high), the excess level (overspeed level) of the vehicle speed VB with respect to the allowable approach speed V ^* is determined. The configuration is as follows.

For example, if the thresholds are V ^* 1, V ^* 2 (however,
V ^* 1 = V ^* + V1, V ^* 2 = V ^* + V2, 0 <V1 <
V2), the speed excess level can be classified into three stages of a small excess (level 1), a medium excess (level 2), and a large excess (level 3) as described below. V ^* <VB ≦ V ^* 1 (Level 1) V ^* 1 <VB ≦ V ^* 2 (Level 2) V ^* 2 <VB (Level 3) The above V1 and V2 are, for example, V1 = 5 km / h, V2
= 20 km / h.

[0098] The result of such a classification determination can be used for a warning or vehicle speed control described later. Further, the classification of the speed excess level is not limited to the three types as described above, and may be provided in an appropriate number. (4) Correction of Permissible Entry Lateral Acceleration Incidentally, the above-mentioned permissible entry lateral acceleration Gy ^* is not limited to the one corresponding to only the vehicle speed. It may be changed according to the parameters. Therefore, in this device,
As shown in FIG. 1, correction means 38A, 38B, and 38C are provided, and correction is performed based on factors other than the vehicle speed, as described below. Approach lateral acceleration Gy ^* corrected for
Based on a. Road width correspondence correction The driver can afford a relatively large lateral acceleration when the road width of the curved road is large when traveling on a curve, but a relatively small lateral acceleration occurs when the road width of the curved road is small. Even at the stage, there is no room to easily feel a sense of danger. Of course, the allowable lateral lateral acceleration Gy ^* when entering the curve also corresponds to the road width, and the degree of danger felt by the driver when entering the curve differs depending on the road width.

Then, in the road width correspondence correcting means 38A,
For example, as shown in FIG. 20, it is conceivable to change the allowable approach lateral acceleration Gy ^* according to the road width. That is, if the road width is large, the allowable approach lateral acceleration Gy ^* is increased, and if the road width is small, the allowable approach lateral acceleration Gy ^* is reduced. In this embodiment, all roads are classified into two types according to their attributes (road width), for example, roads with a higher classification rank (thick roads) and roads other than these (thin roads).
The system is broadly classified into systems and the correction of the allowable approach lateral acceleration Gy ^* with respect to the road width is simplified.

[0100] Then, the thick the road used as the allowable approach lateral acceleration Gy ^* that is set based on the target lateral acceleration value Gy _th trace control, the thin road, as in the following equation, the target lateral acceleration value of the trace control The allowable approach lateral acceleration Gy ^* set based on Gy _th is corrected. Gy ^* = Gy ^* -K2 (where K2> 0) b. Driving characteristic correspondence correction Allowable lateral acceleration Gy when entering a curve
^* Varies depending on the driver's mood and driving characteristics. In other words, if the driver wants to run slowly, even a small lateral acceleration Gy ^* feels dangerous, so it is appropriate to set the allowable approach lateral acceleration Gy ^* low.
If the driver wants to run crisp, there is no danger until the lateral acceleration Gy ^* becomes relatively large. Therefore, it is suitable to set the allowable approach lateral acceleration Gy ^* high.

As described above, the present device is provided with the driving characteristic estimating means 78 for estimating the driving characteristics (the degree of loose running / the crisp running) of the driver, and is used in the trace control system 70. However, also in this device, the driving characteristic (crispness) α estimated by the driving characteristic estimating means 78 is used, and the driving characteristic corresponding correction means 38B according to the crispness α according to the following equation: Permissible approach lateral acceleration G corrected for road width
y ^* is corrected.

Gy ^* = Gy ^* + α · K3 (however,
K3 ≒ 0.2G) Note that the crisp driving degree α is 0 ≦
α ≦ 1 (0 when driving the slowest, 1 when driving the fastest). FIG. 21 shows this correction, for example. c. The curve radius error correction correction determining means 30 determines whether the vehicle speed VB is too high by comparing the allowable approach lateral acceleration Gy ^* with the expected lateral acceleration Gypre, but uses the curve radius R to calculate the expected lateral acceleration Gypre. Therefore, the magnitude of the curve radius R greatly affects the vehicle speed determination. However, since the curve radius R is calculated based on the information from the navigation system 50 as described above, it is not always calculated with high accuracy. Will happen.

That is, at present, the map information stored in the navigation system 50 is generally written in a CD-ROM based on a 1/25000 scale map (Geographical Survey Institute map) based on an aerial photograph. Errors that occur when creating maps from maps and CD-R
Errors accumulate due to errors occurring when writing to the OM and the limit of the dot pitch to be written to the CD-ROM.
Therefore, an error naturally occurs in the value of the curve radius R calculated based on such map information.

If an error occurs in the calculated value of the curve radius R as described above, an error occurs in the vehicle speed determination, and the actual vehicle speed VB
May not be performed even though warning and control are required because the vehicle speed is too large, or a warning and control may be performed when the vehicle speed VB is not too high. Performing this operation without the need for alarms and controls is a safe operation, so it does not cause a serious problem. However, failure to perform the necessary alarms and controls may give a sense of danger to the driver.

Therefore, even if a calculation error occurs in the curve radius R, it is necessary to ensure that necessary alarms and controls can be executed. Here, the curve radius error correction means 38
By C, the allowable approach lateral acceleration Gy, which is a criterion of the vehicle speed,
^* Is corrected so that there is an allowance for the calculation error of the curve radius R. First, in order to examine a calculation error of the curve radius R, a correlation between a curve radius calculated based on information from the navigation system and a curve radius obtained kinematically during traveling of the vehicle is experimentally obtained. There is a characteristic as shown in FIG. As shown in the figure, it can be seen from the result that the curve radius calculated based on the information of the navigation system is within an error range of about ± 20%.

As described above, if there is an error of about ± 20% in the curve radius R, the expected lateral acceleration Gypre (= Gy) at the time of entering the curve is also changed according to the actual value (curve in FIG. 23). Ga) has an error of about ± 20% to the curve Gb on the plus side and to the curve Gc on the minus side. In particular, when the error of the expected lateral acceleration Gypre is on the negative side (curve Gc),
Since the lateral acceleration Gy is estimated to be smaller than the actual value, a situation may occur in which the originally necessary warning or control is not executed.

Therefore, in this embodiment, as shown in FIG. 24, the value of the allowable lateral lateral acceleration Gy ^* that has been corrected for the road width and for the driving characteristics is calculated as the error rate K4 (K4 = −4).
[Gy ^* = Gy ^* × (1+
K4)], so as to correspond to the expected lateral acceleration Gypre including an error of about −20%. According to this, when the negative error of the expected lateral acceleration Gypre does not reach -20% (−20 <error <0), when there is no error, or when the error is positive, the lateral acceleration Gypre is actually Even if the original allowable lateral acceleration Gy ^* has not been reached, it is determined that the vehicle speed VB is too high. However, since this is a safe direction, it is not considered to be a particular problem. 3.3 Non-conformity control (vehicle speed excess control) In the non-conformity control means 40, when the judgment means 30 judges that the vehicle speed VB is too high to enter the curve ahead,
An alarm indicating that a curve exists ahead is generated and control of the running state (speed) of the vehicle is performed. However, it is necessary to generate an alarm and start the speed control at an appropriate timing. Therefore, the present apparatus is provided with an alarm / control start determining means 42 for determining the start of an alarm or control. (1) Alarm / Control Start Determination The alarm / control start determination unit 42 includes an alarm / control start distance setting unit 42A and an alarm / control start determination unit 42B.

The alarm / control start distance setting section 42A sets how far ahead of the curve start point LS detected by the curve detecting means 20 the alarm / control start is started. The distance (warning / control start distance) Lneed from the control start point to the curve start point LS is set as follows. a. As shown in configuration diagram 25 of an alarm and control start distance Lneed, in before the curve, not correlated much the magnitude of the braking start position by the driver curve radius R, but rather, by the size of the current vehicle speed VB It can be seen that the decision has been made. Therefore, here, FIG.
From the characteristic of No. 5, the alarm / control start distance (in the present embodiment, mainly the distance to start the alarm,
Lneed (called an alarm start distance) is calculated. Lneed = α · VB−β [m] However, when the vehicle speed VB is equal to or less than a predetermined value (here, 50 km / h), an alarm is issued in order to maintain the matching between the alarm operation by the nonconforming control unit 40 and the operation. Start distance L
The need is set to a constant value (for example, 30 m).

This is because the non-conformity control means 40 operates a predetermined time (for example, two seconds) after the alarm means 44 is activated.
If the alarm start distance Lneed is too short, the predetermined time (here, 2
This is because the vehicle enters the curve during the second). Therefore, when the vehicle speed VB is equal to or less than the predetermined value, the alarm start distance L
The need is clipped to a predetermined value.
FIG. 26 is a graph showing the relationship between B and the alarm start distance Lneed.

By the way, as described above, at present, there is an error in map information based on information from the navigation system 50. In addition, the error also affects the detection of the position of the own vehicle, and an error occurs in the distance between the vehicle and the curve start point P. If this error is small, the warning start distance Lneed may be set by using the above equation ignoring this error. However, in practice, the information error (navigation error) from the navigation system 50 is relatively large, and It is not possible.

That is, although the vehicle actually enters the alarm start distance Lneed to the curve start point P, the vehicle has not yet entered the alarm start distance Lneed due to an error in the navigation system 50. It is conceivable that this is determined. Of course, on the contrary, it is conceivable that it is determined that the vehicle has entered the alarm start distance Lneed even though the vehicle has not actually entered the alarm start distance Lneed. In this case, there is no particular problem because the alarm operation and the control operation are performed earlier than the original timing.

Therefore, it is necessary to set the alarm start distance Lneed in consideration of the navigation error. In this case, in the simplest case, the alarm start distance Lneed may be newly set in addition to the alarm start distance Lneed by the assumed maximum value LEmax (for example, 40 m) of the navigation error. That is, assuming that an alarm start distance in consideration of a navigation error is Lneed ^* , the alarm start distance Lne
ed ^* is as follows. Lneed ^* = Lneed + LEmax However, in such a setting, if a navigation error occurs in a direction in which the distance to the curve is determined to be shorter than the actual one, the timing of the curve warning or control may be too early.

Therefore, in the present embodiment, the alarm start distance Lneed ^* considering the navigation error is set as follows. Lneed ^* = Llimit + LEmax That is, even if the start of the brake operation is delayed by the maximum LEmax due to a navigation error, the minimum braking margin Llimit is set.

Here, Llimit is equivalent to the area shown in FIG. 27, and the free running distance that the vehicle advances from hearing the warning until the driver depresses the brake, and the driver depresses the brake, The current vehicle speed VB is added to the target vehicle speed (permissible traveling speed) V ^* and the distance traveled while decelerating. For example, the idle running time is 0.5 seconds, the reference deceleration G
x is 3 m / s ² , the reference lateral acceleration (allowable lateral acceleration) Gy is 6 m / s ^2, and the units of the velocities VB and V ^* are [k
m / h], Llimit = 0.5 (VB / 3.6) + [(VB / 3.6) ^2- (V ^* / 3.6) ² ] / (2Gx).

In the above equation, (V ^{* /} 3.6) ² = Gy
By substituting R = 6R or deceleration ^{Gx = 3m / s 2, Llimit} = 0.5 (VB /3.6)Tasu〔(VB /3.6) ² -6R] / 6 = 0.139VB +0. 0129VB the ² -R. Therefore, Lneed ^* is a ^{Lneed * = Llimit + LEmax = 0.139VB} + 0.0129VB 2 -R + LEmax.

[0116] Incidentally, setting the navigation error LEmax example, ^{40m, Lneed * = 0.139VB + 0.0129VB} 2 -R + 40 a (m). The alarm start distance Lneed when there is no navigation error and the alarm start distance Lneed when the above error is corrected
FIG. 28 shows ^* in a graph. This FIG.
As shown in the graph, Lneed ^* >
Lneed, the warning start distance is usually Lneed
^{* Will} be set.

However, in an area where the vehicle speed VB is low, the alarm start distance Lneed ^* is less than 40 m (= the maximum value LEmax of the navigation error). In this case, the alarm start distance Lneed ^* is set to LEmax (40 m in this case). To be clipped. When Lneed> Lneed ^* , Lneed is selected as the alarm start distance.

The warning start distance Lneed ^* in consideration of the navigation error described above is the allowable lateral acceleration G when traveling on a curve.
Although y is calculated as 6 m / s ² , the driver hears the warning by the warning means 44 just before the curve, and performs a deceleration operation (deceleration Gx = 6 m / s) within a predetermined time (for example, 2 seconds).
² ) When the vehicle enters the curve by performing the above, the allowable lateral acceleration Gy is set to 3 m / s ² and the alarm start distance Lneed ^* is set so that the lateral acceleration generated at the curve is within the normal 3 m / s ^{2 .}
May be calculated.

Therefore, (V ^{* /} 3.6) ² = Gy
By substituting R = 3R, deceleration ^{Gx = 6m / s 2, Llimit} = 0.5 (VB /3.6)Tasu〔(VB /3.6) ² -3R] / 12 = 0.139VB +0. ^{00643VB 2 -0.25R Lneed * = 0.139VB +} 0.00643VB 2 -0.25R + 40 a (m).

Also in this case, if Lneed ^* > Lneed, Lneed ^* is selected as the alarm start distance, and Lneed ^* <Lneed.
If so, Lneed is selected as the alarm start distance. Further, similarly to the above, the alarm start distance Lneed ^*
Is less than 40 m (= the maximum value LEmax of the navigation error), Lneed ^* is clipped to 40 m.

When the alarm start distance Lneed ^* is set in this way, the alarm / control start determination section 42B outputs an alarm / control start signal when the vehicle position reaches a location corresponding to the alarm start distance Lneed ^*. I do. That is, the information of the curve start point LS detected by the curve detection means 20 and the start distance L set by the alarm / control start distance setting means 42A.
Based on the information on need ^* and the current position information from the current position estimating means 56, a control start signal is output when the vehicle enters the warning / control start point.

As described above, the alarm / control start determining means 42 of the present apparatus sets the alarm control start distance in consideration of the error of the start point position of the curve caused by the error of the information from the navigation system 50. By this, the alarm control start distance can be set accurately,
The warning and the vehicle speed control of the vehicle can be performed safely without delaying the start of the warning and the vehicle speed control.

The alarm control start determining means 42 determines the alarm control start distance Lneed based on the linear relationship between the vehicle speed VB and the braking start distance to the curve start point as shown in FIG.
Is advantageous in that the alarm control start distance Lneed can be easily calculated. Further, the curve detecting means 20 detects the radius R of the curve,
The alarm control start determining means 42 calculates a target vehicle speed V ^* at the time of entering the curve from the preset target lateral acceleration Gy at the time of entering the curve and the curve radius R, and sets a target deceleration Gx from the current vehicle speed VB of the vehicle. If the alarm control start distance is set based on the deceleration distance when the vehicle is decelerated to the vehicle speed V ^* and the idle distance of the vehicle, the alarm control start distance actually required for alarm and vehicle speed control is calculated. Can be.

If the alarm control start determining means 42 increases and corrects the alarm control start distance Lneed by the error error LEmax of the road information stored in the navigation system 50, the alarm control can be easily performed by a simple calculation formula. The starting distance can be corrected. On the other hand, the alarm control start determining means 42
Then, the target vehicle speed V ^* at the time of entering the curve is calculated from the preset reference lateral acceleration Gy at the time of entering the curve and the curve radius R detected by the curve detecting means 20, and the current vehicle speed V of the vehicle is calculated.
The first alarm control start distance Llimit + is calculated by adding the deceleration distance when the vehicle is decelerated from B to the target vehicle speed at the reference deceleration Gx, the idle distance of the vehicle, and the distance corresponding to the error of the start point position of the curve.
LEmax is calculated, and the second alarm control start distance is calculated by adding the braking start distance to the curve start point having a linear relationship with the vehicle speed VB, the idle running distance of the vehicle, and the distance corresponding to the error of the curve start point position. Lneed + LEmax is calculated, and these first and second values are calculated.
Alarm control start distance Llimit + LEmax, Lneed + LEmax
If the maximum distance among the three distances, ie, the distance LEmax corresponding to the error of the curve start point position and the distance LEmax, is set as the alarm control start distance, the alarm control start distance can be reliably corrected. The warning and the vehicle speed control of the vehicle can be safely performed without delaying the start of the warning and the vehicle speed control. (2) control content (the vehicle speed over time control contents) during incompatible incompatible when the control section 40, an alarm unit (audio information control unit) 44, a throttle opening-automatic transmission control unit (throttle-AT control means) The vehicle is provided with a vehicle speed control means 46. The voice information control means 44 controls a voice alarm before entering the curve, and the throttle / AT control means 46 controls the throttle opening of the engine before entering the curve and the automatic transmission. Shift control is performed. a. Exclusion from Control Target The non-conformity control means 40 of the present apparatus is set so that such a sound alarm and throttle / AT control are performed only when the vehicle speed is equal to or higher than a certain vehicle speed. That is, when the vehicle speed VB is input from the vehicle speed sensor 84 and the vehicle speed VB is equal to or higher than the set value V0 (for example, 30 km / h), the non-conforming control unit 40 performs an alarm or control. In such a case, no warning or control is performed.

This is because at a low vehicle speed, unless a sharp curve with a very small curve radius is entered, excessive lateral acceleration does not occur even if the vehicle enters the curve as it is. If so, it is considered that the driver can adjust the vehicle speed suitable for the curve with a margin. In addition, by limiting the area in which the alarm or control is performed, the frequency of the alarm or the control can be reduced, so that the effect of the alarm is increased,
It is conceivable that the AT control is stabilized.

In the present apparatus, the curve detecting means 2
In some cases, a curved road detected at 0 may include a right turn or a left turn at an intersection (including a branch point). That is, in the curve detecting means 20, the optimum route B as shown in FIG.
Since a curve is detected from information on R (solid line), it is not known whether or not the bent portion BP of the optimal route BR is an intersection. If the route BR is in a predetermined bent state, it is determined that the route is a curve. Therefore, for example, the intersection P1 and the branch point P2 shown in FIG. 29 may be determined as a curve.
Note that the two-dot chain line in FIG. 29 indicates a road other than the optimal route BR.

When turning right or left at such an intersection P1 or a junction P2, navigation information as to where to turn is issued in advance, so that there is no need to warn that "there is a curve". This alert is not appropriate for intersections. Further, since the navigation information is usually performed at any time from a stage having a sufficient time, if the throttle / AT control is performed, the driver may feel uncomfortable.

Therefore, the non-conformity control means 40 of the present apparatus uses the curve detection means 20 based on the detection information from the curve detection means 20 and the intersection information added to the road map information from the road map information storage means 52. The curve corresponding to the intersection among the curves detected in step (1) is set so as not to perform the voice alarm and the throttle / AT control.

Hereinafter, the alarm control, the throttle control, and the AT control will be described in detail. (3) Alarm control a. Warning voice content The warning means (voice information control means) 44 warns a single curve with a message such as "This is the curve ahead."
For a continuous curve, an alarm is issued with a message such as "The curve continues ahead." Or "It is a continuous curve. Please be careful." Of course, as described above, this warning is issued when the vehicle speed VB is equal to or higher than the set vehicle speed V0 (for example, 30 km / h) and the target curve is not an intersection.

Further, in the above-mentioned vehicle speed judging means 30,
Although the overspeed level before the curve is determined, the present apparatus changes the message content according to the overspeed level as follows. That is, the vehicle speed VB is V ^* <VB
In the case of a small excess (level 1) such as ≤V ^* + V1, for a single curve, a warning message such as "It is a curve ahead." Or "Please be careful." For a continuous curve, a warning message such as "The curve ahead is continuous." Or "Continuous curve. Please be careful." Is issued, but the vehicle speed VB is V ^* + V1.
Medium excess (level 2) such as <VB ≤ V ^* + V2 and vehicle speed VB
Is larger than V ^* + V2 <VB (level 3), an alarm is issued as follows.

In other words, when the vehicle speed is medium excess (level 2), a warning is issued for a single curve with a message such as "This is the curve ahead. Please decelerate." , "The curve will continue ahead. Decelerate." If the vehicle speed is too high (level 3), for a single curve, "Dangerous. Step on the brakes."
Warning with the content of a message such as
It warns with a message such as "The curve is continuous and dangerous. Step on the brake."

As a result, it is possible to urge the driver to pay attention to the curve and take an action to be performed so as to respond to the excessive vehicle speed. b. Warning sound generation timing The warning sound is generated after the vehicle approaches the curve start point LS by a distance equal to the warning start distance Lneed ^* . In other words, basically, the vehicle is located at the warning start distance Lneed from the curve start point LS.
^{If the} vehicle speed VB is determined to be too high (Gypre> Gy ^* ) by the determination means 30 when the vehicle reaches the point just before ^* ,
Give an alarm.

Further, the vehicle is warned more than the curve start point LS.
Start distance Lneed^*When the alarm start point is reached in minutes
The vehicle speed VB is too high (Gypre>
Gy ^*), But after this, from the alarm start point
Is also close to the start point LS of the curve,
The vehicle speed VB is too high in the determination means 30 (Gypre> G
y^*) May be determined.

In this apparatus, an alarm is issued even in such a case. For this reason, the voice information control means 4
In 4, when the vehicle reaches the alarm start point, unless it is determined that the vehicle speed VB is too high (Gypre> Gy ^* ),
The information of the vehicle speed judgment (whether Gypre> Gy ^* or not) is fetched in a required short cycle until reaching the curve start point LS. c. Voice Priority By the way, such an alarm is output as voice information through voice information generating means 92 using an audio system.
As described above, the audio information relating to the navigation is also output to No. 2, so that there is a possibility that the two audio information may collide with each other. Therefore, in the present apparatus, the information is ranked, and the voice information is output in order according to the priority.

In the navigation, when it is necessary to make a right or left turn at an intersection or a junction, or when approaching a destination, a message is issued in a stepwise manner. That is, at a point, for example, N kilometers before an intersection or a junction, a primary message such as "N kilometers ahead, right (left) direction" is issued, and at a point, for example, n hundred meters before an intersection or junction, A secondary message such as “n hundred meters ahead, right (left) direction” is issued, and at a point where the intersection or junction is, for example, several tens of meters before or where the intersection or junction is visible, “soon, right (left ) Direction. "Etc. (final navigation voice information).

At a point, for example, N kilometers before the destination, a primary message such as "I will arrive at another N kilometers." Is issued, and at a point, for example, n hundred meters before the destination, "N. At one hundred meters we will arrive. "
At the point where the destination can be seen, for example, tens of meters before the destination, or "Soon,
Arrive. , Etc. (final navigation voice information).

In the order of the curve information and the navigation information, the navigation final message is given priority first, but the curve information is given priority next. Therefore, the curve information has priority over the order of the navigation information other than the last message. For example, the order of the navigation information and the curve information at each stage regarding the intersection is as follows.

"Soon, right (left) direction.""The curve is ahead." Or "The curve continues.""N hundred meters ahead, right (left) direction.""N kilometers ahead, right ( Therefore, for example, if the final navigation audio information and the curve information overlap, for example, the audio information of "soon, right (left) direction." Will happen. If the navigation information other than the last information and the curve information overlap, the "curve ahead,""n hundred meters ahead,
Right (left) direction. Is continuously generated.

[0139] The final navigation voice information is prioritized over the curve information for the following reason.
That is, if the final navigation voice information is issued at an inappropriate timing during route guidance, the original performance of the route guidance may not be exhibited. Therefore, it is desired to emit the final navigation voice information at an appropriate timing. In addition, when the final navigation voice information is performed, the driver usually suppresses the vehicle speed to increase attention to the road condition ahead, and it is considered that this voice information can also cope with a curve ahead. is there. Of course, since the curve information is transmitted following the final navigation voice information, the driver can be surely recognized the curve ahead. d. Alarm interruption control in continuous curve As described above, the information content of the alarm sound is changed according to the type of curve such as a single curve or a continuous curve. ,
The curve warning and the speed control described later are interrupted (temporarily prohibited) only for a certain traveling distance.

Such a continuous curve includes, for example, a curved road in a mountain area, and a large number of curves may be continuous. However, if an alarm is issued for each curve under such a road condition, the driver feels troublesome. It is possible. Of course, even in such a continuous curve, an alarm is not issued if the speed of the vehicle is suppressed, but in the case of a driver performing so-called crisp driving, an alarm is issued for each curve without suppressing the speed of the vehicle. Such a situation is conceivable.

Therefore, the curve warning is interrupted only for a certain traveling distance (for example, several hundred meters). The logic of alarm control according to such a curve type can be shown as in FIG. First, as shown in step A1, when a curve is detected, it is determined whether or not this curve is a continuous curve.

In this determination, a first curve having a start point L ₁₁ and an end point L ₂₁ exists in front of the vehicle, and a second curve having a start point L ₁₂ and an end point L ₂₂ ahead of the first curve. When there is a curve, the distance (inter-curve distance) Lstrait of the straight line portion connecting these two curves (this Lstrait is equivalent to D ₀ in FIG. 18) is a predetermined value (for example,
If it is less than 200 meters in the case shown in FIG. 30, it is determined that the curve is a continuous curve.

Conversely, when the distance Lstrait between curves is a predetermined value (2
00m) or more, and the distance between curves Lstrait
Is unknown, it is determined to be a single curve. The inter-curve distance Lstrait is unknown when the second curve cannot be detected beyond the first curve. Curve detection is limited to a certain extent in front of the current position of the vehicle due to restrictions on calculation speed and the like. The second curve may not be detected when the distance from the first curve to the second curve is large or the first curve itself is long, since the second curve is performed. . In such a case, the first curve is processed as a single curve.

If it is determined that the curve ahead of the vehicle (first curve) is a single curve, a single curve warning of "this is the curve ahead" is issued as shown in step A2. Of course, the warning is at a point before only the alarm starting distance Lneed ^* min than the starting point L ₁₁ of the curve, and when it is determined that the vehicle speed VB is too high (Gypre> Gy ^*), than the start point L ₁₁ At a point just before the warning start distance Lneed ^* , the vehicle speed VB is too high (Gypre>
Gy ^*) and is not determined, the vehicle speed VB is too high the assumption close to the starting point L ₁₁ from this point (Gypre> G
y ^* ).

If it is determined that the curve ahead of the vehicle (the first curve) is a continuous curve, a continuous curve warning of "the curve continues" is issued as shown in step A3. Of course, this warning is also at a point in front by the alarm starting distance Lneed ^* min than the starting point L ₁₁ of the curve, and when it is determined that the vehicle speed VB is too high (Gypre> Gy ^*), than the start point L ₁₁ At a point just before the warning start distance Lneed ^* , the vehicle speed VB is too high (Gypre>
Gy ^*) and is not determined, the vehicle speed VB is too high the assumption close to the starting point L ₁₁ from this point (Gypre> G
y ^* ).

Then, after issuing the continuous curve warning of "The curve continues.", As shown in step A4,
The travel distance Lpast of the vehicle after the warning is calculated, and the curve warning is interrupted until the travel distance Lpast reaches a predetermined travel distance (several hundred meters). e. Processing of a continuous curve that could not be detected before the occurrence of the curve alarm As described above, when the distance Lstrait between curves becomes unknown,
Although the first curve is processed as a single curve, the distance Lstrait between the curves is unknown. However, when the first curve itself is long or the alarm or control processing for the first curve is performed, the first curve is not processed. In some cases, curve 2 cannot be detected. Even in such a case, as the vehicle travels along the first curve, the second curve ahead of the first curve can be detected.

If the distance Lstrait between the first curve and the second curve is smaller than a predetermined value (200 meters), the curve is a continuous curve. Since no alarm interruption control is performed, an alarm relating to the second curve can be issued. Of course, there is no problem if the inter-curve distance Lstrait is greater than or equal to the alarm start distance Lneed ^*. However, if the inter-curve distance Lstrait is less than the alarm start distance Lneed ^* , the second curve is obtained even though the first curve has not ended. The driver will be warned of the curve, giving the driver a sense of discomfort.

In order not to give such a feeling of strangeness, it is necessary to set so as not to issue an alarm for the second curve until the first curve is completed. But,
In this case, the distance Lstrait between the curves is the alarm start distance Lneed
^{Since it is} less than ^* and short, after all, it is necessary to issue an alarm for the second curve as soon as the first curve is completed.

However, if the inter-curve distance Lstrait is too short, there is a case where there is no effect even if an alarm for the second curve is issued at the end of the first curve. In consideration of such a situation, the present apparatus performs the following processing. That is, the curve distance Lstrait
Is greater than or equal to a predetermined distance (for example, 20 meters), a warning is issued for the second curve when the first curve ends. If the distance Lstrait between the curves is less than a predetermined distance (for example, 20 meters), no alarm is issued for the second curve. As a result, ineffective alarms will not be issued,
The driver will not feel uncomfortable. f. Exception Processing During Alarm Interruption Control on a Continuous Curve As described above, alarm interruption control is performed on a continuous curve, but a large lateral acceleration is expected to occur in the middle of the continuous curve as compared to the previous curve. When there is a sharp curve (so-called hairpin curve), the necessity of an alarm is extremely high. Therefore, when such a sharp curve (hairpin curve) exists, the alarm interruption control is performed even during the alarm interruption control. Is temporarily stopped, a curve alarm is issued, and the control returns to the alarm interruption control again.
The presence of the hairpin curve can be detected from the detection information from the curve detection means 20.
In this case, the curve warning may be performed with a specific message content such as "a sharp curve (or a hairpin curve)". (4) Overview of vehicle speed control (throttle control and shift-down control) Vehicle speed control is performed through throttle control and shift-down control. If the driver does not try to lower the vehicle speed, another warning (vehicle speed control) different from the sound is given again to urge the driver to decelerate. A second object is to try to urge the driver to decelerate when a curve warning cannot be issued.

Therefore, the vehicle speed control is performed when the driver does not try to lower the vehicle speed within a predetermined time t2 (for example, 2 seconds) after the curve warning. By the way, when the driver tries to decrease the vehicle speed, the driver first releases the depression of the accelerator pedal, and then depresses the brake pedal. However, when the vehicle speed VB is slightly decreased, the accelerator pedal may be released only by depressing the accelerator pedal, and the vehicle may be decelerated only by the engine brake without depressing the brake pedal.

Therefore, in this vehicle speed control, if it is determined that the vehicle can be decelerated only by the engine brake at the time of determining the curve warning, it is determined whether or not the accelerator pedal is released (that is, the accelerator opening becomes zero). Whether the vehicle speed control has been started, and if it can be determined that the vehicle cannot be decelerated using only the engine brake, whether or not the brake pedal has been depressed (that is, whether the brake switch is on or off) The start of the vehicle speed control is determined.

The determination as to whether or not the vehicle can be decelerated only by the engine brake is made based on the above-mentioned overspeed level. That is, when the vehicle speed VB is V ^* <VB ≦
In the case of a small excess (level 1) such as V ^* + V1, the vehicle can be decelerated only by the engine brake, and the vehicle speed VB becomes V ^*
In the case of + V1 <VB (medium excess (level 2) and large excess (level 3)), it is assumed that the vehicle cannot be decelerated only by the engine brake.

The vehicle speed control is performed by one of the throttle control and the downshift control. That is, if the accelerator pedal is depressed, throttle control is used, and if the accelerator pedal is not depressed, downshift control is used. The determination of the accelerator pedal is made t2 (2 seconds) from the curve alarm.
I will do it later.

Therefore, if the accelerator pedal is not released after the curve warning, the throttle control is used. If the accelerator pedal is released after the curve warning, the vehicle speed is slightly exceeded (level) when the curve warning is determined. If determined as 1), the vehicle speed control is not performed,
If it is determined that the vehicle speed is medium excess (level 2) or more at the time of the curve alarm determination, the vehicle speed control is performed using the shift-down control.

Hereinafter, the throttle control and the downshift control will be described. (5) Throttle control a. Control contents In this throttle control, when a vehicle speed limit command is issued, the actual engine output torque T
This is a control for temporarily suppressing E and causing the driver to perceive danger. For example, a torque correction coefficient C1 having a characteristic as shown in FIG. Is set, and the throttle opening of the engine is controlled through the throttle driving means 94.

TE = C1.TM As a result, the engine output torque TE is instantaneously suppressed to 50% of the driver required torque TM at the start of the control, and thereafter, during t3 (for example, 3 seconds), the engine output torque TE becomes 100%.
% Is returned to the linear shape. Even during this time t3 (for example, 3 seconds), if the later-described ending condition is satisfied, the throttle control ends at that time, so that the throttle control is performed only for a maximum of t3 (for example, 3 seconds).

However, the following start condition and end condition are given to the throttle control. b. Throttle control start condition Throttle control is basically started when the driver depresses the accelerator pedal at time t2 (for example, 2 seconds) after the curve alarm is issued. Are both satisfied.

When the vehicle speed VB is equal to the set value V0 (for example, 30 km /
h) It must be at least. The driver depresses the accelerator pedal at time t2 (for example, 2 seconds) after the generation of the curve alarm. As with the alarm condition, it is considered that if the vehicle speed is low, the driver can adjust to a vehicle speed suitable for the curve with a margin, and in particular, it is considered that control for making the driver aware of danger is unnecessary. It is.

The condition is an essential condition for throttle control. That is, the throttle control is a control for reducing the engine torque output with respect to the driver request torque TM as described above, and is a control that cannot be executed without the driver request torque TM, that is, unless the accelerator pedal is depressed. It is. Further, the time lag is provided between the time point t2 (for example, 2 seconds) after the occurrence of the curve alarm and the curve alarm because the throttle control is performed by the driver even when the curve alarm control is performed. This is because it is positioned as a second warning operation to cope with a case where there is no warning. c. Throttle Control Termination Condition Throttle control is terminated at t3 (for example, 3 seconds) as described above. However, when the driver indicates the intention of acceleration during throttle control or enters the curve and trace control is started. In this case, the throttle control is terminated halfway even if this time t3 (for example, 3 seconds) has not elapsed, and any of the following conditions is satisfied.

When a time t3 (for example, 3 seconds) has elapsed since the start of the throttle control. When the driver indicates willingness to accelerate during throttle control. When trace control is started during throttle control. The driver's intention to accelerate under the condition can be detected by the accelerator pedal opening (accelerator opening). For example, if the accelerator opening itself increases, it can be considered that the driver indicates the intention to accelerate.Also, even if the accelerator opening does not increase, if the accelerator pedal is depressed a certain amount or more, the driver will still It can be thought that it shows the will to accelerate.

In this device, from such a viewpoint, if the accelerator opening is less than 50% at the start of the throttle control, the throttle control is started when the accelerator opening increases to 50% or more after the start of the throttle control. If the accelerator opening is 50% or more at the start, the throttle control is set to end when the cumulative value of the accelerator pedal depression operation reaches 20% of the accelerator opening after the start of the throttle control. I have.

The condition is that when the vehicle enters the curve and the tracing control is started, the driver can naturally recognize the existence of the curve and must not interfere with the tracing control. The throttle control as the situation control is ended. d. Other Conditions Concerning Throttle Control It is set so that once the control (throttle control or downshift control) is completed, the curve is not controlled again. That is, for example, the throttle control is not performed on a curve in which the shift-down control described later is completed by the accelerator-on.

This is because the vehicle speed control (throttle control or downshift control) for the same curve is performed only once, so as to suppress the adverse effects of the vehicle speed control. In other words, it is considered sufficient to perform a slight deceleration control at an appropriate timing to promote deceleration, and if this deceleration control is too strong or is performed many times, it may rather give the driver great discomfort. Conceivable. Therefore, the content of the throttle control is set so that the deceleration control does not become excessive, and this condition is set so that the vehicle speed control (throttle control or downshift control) is not performed many times on the same curve.

When the vehicle starts to warn from the curve start point LS
Distance Lneed^*When the alarm start point is reached
Means that the vehicle speed VB is too high (Gypre> G
y^*), But after this,
At a point close to the start point LS of the curve,
Vehicle speed VB is too high (Gypre> Gy)
^*)), It becomes t after the curve alarm
2 (for example, 2 seconds), the throttle control start condition
Is satisfied, and the curve start point LS is reached.
Only when not, throttle control is performed.

Even when the alarm is interrupted on the continuous curve, if the throttle control start condition is satisfied, the throttle control is performed in the following cases. If the distance Lstrait between the curves is greater than the alarm start distance Lneed ^{*, the} alarm start distance Lneed is greater than the curve start point LS
^* Throttle control is performed when the alarm start point is reached just before the minute.

The distance Lstrait between the curves is the alarm start distance L
If it is less than need ^* but not less than a predetermined distance (for example, 20 meters), throttle control is performed when the first curve ends. If the distance Lstrait between curves is smaller than the warning start distance Lneed ^{* and} smaller than a predetermined distance (for example, 20 meters), the throttle control is not performed. In the case of a continuous curve that could not be detected before the curve alarm occurred, if the throttle control start condition was satisfied,
The control is executed in the same manner as the curve warning.

That is, as the vehicle travels on the first curve, the second curve ahead of the first curve can be detected. As a result, the curve between the first curve and the second curve can be detected. There is no problem if the distance Lstrait is longer than the alarm start distance Lneed ^*, but if the distance Lstrait is less than the alarm start distance Lneed ^* , the throttle control is performed as follows when the throttle control start condition is satisfied. It is.

The distance Lstrait between curves is the alarm start distance L
If it is less than need ^* but not less than a predetermined distance (for example, 20 meters), a warning is issued for the second curve when the first curve is completed, and at the same time, throttle control is performed. If the distance Lstrait between curves is less than a predetermined distance (for example, 20 meters), throttle control is not performed as in the case of the curve warning for the second curve. (6) Shift down control a. Control Details This downshift control is performed when the driver does not depress the accelerator pedal. That is, since the throttle control is a control for temporarily suppressing the actual engine output torque TE with respect to the driver request torque TM so as to satisfy the start condition, the throttle control cannot be executed unless the driver depresses the accelerator pedal. . Therefore, when the accelerator pedal is not depressed in this way, a command signal is issued to the ECU (electronic control unit) 96 for the automatic transmission to perform downshift control, thereby causing the driver to detect danger due to vehicle speed limitation. It is.

In this apparatus, this downshift control is performed when the shift position is at the high speed stage and is not performed at the low speed stage. Here, it is assumed that the automatic transmission has five shift speeds. In this case, in principle, if the shift position is the fifth speed, the gear is shifted down to the fourth speed, and the shift position is shifted to the fourth speed. If so, the gear shifts down to the third speed, and if the shift position is equal to or less than the third speed, the gearshift is not performed.

However, if the vehicle speed is in the middle to low speed range and the shift speed is the fifth speed, the downshifting from the fifth speed to the fourth speed has almost no effect on the speed of the vehicle. The effect will be extremely low. Therefore, in the present device, when the vehicle speed is in the middle to low speed range (for example, VB ≦ 70 km / h) and the shift speed is the fifth speed, the fifth to third speeds are obtained so that a warning effect to the driver can be obtained. It is set to shift down at once.

Also, as long as the downshift control is performed on a certain curve and the downshift control is continued, even if a curve alarm or speed control is required for the next curve, the downshift control is performed again. The down control is set not to be performed. This is to avoid excessive downshifting in the running state, but of course, this is not the case once the downshift control is completed.

That is, the shift-down control will be described later in the section on the conditions for terminating the shift-down control. If the shift-down position is lower than the shift position obtained by the normal shift control, the shift-down control is continued. The process ends when the shift position becomes the same as the normal shift position. Therefore, when the downshift control is continued, a gear position lower than the original shift position is selected, and in such a case, further downshifting will result in the shift position being too low. Would. Therefore, the continuous downshift operation is prohibited while the downshift control is continued. b. Shift-Down Control Start Condition The shift-down control is started, in principle, when the driver has not depressed the accelerator pedal at time t2 (for example, 2 seconds) after the alarm was issued. This is the case where all the conditions are satisfied.

When the vehicle speed VB is equal to the set value V0 (for example, 30 km /
h) It must be at least. The driver has not depressed the accelerator pedal at time t2 (for example, 2 seconds) after the generation of the curve alarm. Vehicle speed VB is too high at the time of curve warning judgment (level 2)
It must be judged above.

As with the alarm condition and the throttle control condition, it is considered that if the vehicle speed is low, the driver can adjust to the vehicle speed suitable for the curve with a margin. This is because it is considered unnecessary. The condition is that the present device positions the downshift control as the vehicle speed control to be performed instead of the throttle control when the throttle control cannot be performed. Therefore, the condition of the downshift control is that there is no depression of the accelerator pedal, which is essential for the throttle control.

However, after the curve alarm is generated, t2
The accelerator pedal is depressed at a point in time (for example, 2 seconds). Immediately thereafter, if the accelerator pedal is released before reaching the curve start point LS, the downshift control is executed at this point. Of course, this control is not performed once the curve start point LS has been reached. That is, if the accelerator pedal is depressed at time t2 (for example, 2 seconds) after the curve warning, the throttle control is performed according to the depression amount of the accelerator pedal from this time. If the depression of the accelerator pedal is released before reaching, the throttle control is released at this point and the downshift control is performed.

It is considered that the reason why the driver keeps depressing the accelerator pedal even if the deceleration control by the throttle control is further performed t2 after the curve warning is issued is that the driver does not intentionally decelerate.
If the accelerator pedal is released after the throttle control, it is considered that the driver is about to decelerate in accordance with the throttle control. In this case, the downshift control is performed to assist the driver in decelerating. . c. Shift Down Control Termination Condition The shift down control is set to end when any of the following conditions is satisfied.

When the accelerator pedal is depressed. When the shift position becomes the same as the normal shift position. When trace control is started during downshift control. It can be determined that the accelerator pedal is depressed when the driver feels dissatisfaction with deceleration due to downshifting.In this case, the downshift control is canceled and the driver's will is prioritized, and the downshift is performed. The control prevents the driver from feeling uncomfortable.

The condition is that if the shifted down shift position becomes the same as the shift position by the normal shift control,
Since the shift from the downshift control to the normal shift control can be performed smoothly, the shift down control is terminated at this point and the setting is made so as to return to the normal shift control. Further, by the end of the downshift control, the above-described prohibition of the continuous downshift is also released, and the deceleration control by the new downshift control becomes possible.

The condition is that when the vehicle enters the curve and the trace control is started, the driver can naturally recognize the existence of the curve and must not interfere with the trace control. The shift-down control as the situation response control ends. d. Other conditions related to shift-down control The curve is set so that once the control (throttle control or shift-down control) is completed, the control is not performed again. For example, the downshift control is not performed on the curve for which the throttle has been completed.

This is because, as described above, the vehicle speed control (throttle control or downshift control) for the same curve is performed only once, so as to suppress the adverse effects of this vehicle speed control. The vehicle is at the warning start distance Lneed ^* from the curve start point LS ^*
When the alarm start point is reached by the minute, the judgment means 3
At 0, it is not determined that the vehicle speed VB is too high (Gypre> Gy ^* ).
At the point approaching S, the determination means 30
If it is determined that the vehicle speed VB is too high (Gypre> Gy ^* ) at t2 (for example, 2
Seconds), the shift-down control start condition,
Is satisfied, and the downshift control is performed only when the vehicle has not reached the curve start point LS. Even when the alarm is interrupted in the continuous curve, if the conditions for starting the downshift control are satisfied, the downshift control is performed in the following cases.

The distance Lstrait between the curves is the alarm start distance L
In the case of need ^* or more, the shift down control is performed when the alarm start point is reached just before the alarm start distance Lneed ^* from the curve start point LS. If the distance Lstrait between curves is smaller than the warning start distance Lneed ^* but is equal to or longer than a predetermined distance (for example, 20 meters), the first
The shift down control is performed at the time point when the curve of FIG.

The distance Lstrait between curves is the alarm start distance L
If it is less than need ^{* and} less than a predetermined distance (for example, 20 meters), the downshift control is not performed. In the case of a continuous curve that could not be detected before the occurrence of the curve alarm, if the shift-down control start condition is satisfied, the control is executed in the same manner as the curve alarm. That is,
As the vehicle travels along the first curve, the second curve ahead of the first curve can be detected. As a result, the first curve can be detected.
There is no problem if the distance Lstrait between the second curve and the second curve is equal to or longer than the alarm start distance Lneed ^*. However, if the distance Lstrait between the curves is smaller than the alarm start distance Lneed ^* , the shift-down control start condition, , Hold down control is performed as follows.

The distance Lstrait between the curves is the alarm start distance L
If it is less than need ^* but not less than a predetermined distance (for example, 20 meters), an alarm for the second curve is issued at the same time when the first curve ends, and at the same time, downshift control is performed. If the distance Lstrait between curves is less than a predetermined distance (for example, 20 meters), the downshift control is not performed as in the case of the curve warning for the second curve. 4. Operation of the Apparatus The control apparatus for a road ahead condition according to one embodiment of the present invention is configured as described above, and thus, for example, a warning and a vehicle speed control are performed as shown in FIG. 4.1 Overall Control Operation FIG. 32 is a flowchart showing a main routine relating to the operation of the present apparatus. In the present apparatus, the operation as shown in FIG. 32 is repeated at a required control cycle.

First, the road map data and the current position are read from the road map information storage means 52 and the current position estimation means 56 of the navigation system 50 (step B1).
0), these information are displayed on the display (step B10). Next, it is determined whether or not the route guidance is being performed (step B30). If the route guidance is not being performed, the route guidance processing, the curve warning and the vehicle speed control, which are the main operations of the present apparatus, are not performed, and each flag (flag F1 to F4) is not performed. ) And the timer T are reset to the initial state (step B110), and wait for the next control cycle. Note that the flags F1 to F4 and the timer T
Will be described later.

On the other hand, if the route guidance is being performed, the route guidance process, that is, the guidance route (optimum route) is displayed on the display, and the voice guidance of the intersection or the branch road is appropriately performed (step B4).
0). Note that this voice guidance is performed based on a priority relationship with the curve warning, and if the curve warning has priority, it is postponed or interrupted. Then, a curve detection process is performed (step B50). The detailed operation of this process will be described later, but if the presence of a curve is not detected by this process,
From the determination step of step B60, the necessary flags (flag F1 to F3) and the timer T are reset to the initial state (step B120), and the process stands by in the next control cycle.

If there is a curve, the process proceeds from the determination step of step B60 to step B70, in which it is determined whether the vehicle is within the warning / control start distance Lneed and at a position before entering the curve. The judgment is made by the judgment means 42. If the vehicle is not under this condition, step B120
, And waits for the next control cycle. If it is determined in step B70 that the vehicle is within the warning / control start distance Lneed and before entering the curve, a vehicle speed determination process (step B80) is performed. Although the detailed operation of this processing will be described later, if the current vehicle speed is not too large to enter the curve ahead, from the determination in step B90, the warning / control processing is not performed, and the control waits for the next control cycle. If the vehicle speed is too high for entering the curve, the process proceeds from step B90 to the step B100 from the constant to perform the warning and control (vehicle speed control) described later. 4.2 Curve Detection Operation The curve detection by the curve detection means 20 will be described. For example, the curve detection is performed as shown in a flowchart of FIG.

First, in step C1, the sampling distance L is set by the sampling distance setting means 21, and thereafter, the process proceeds to step C2, where the curvature index calculating means 2
2, a curvature index θ indicating the curve angle is calculated. For example, the curvature index calculating means 22 includes a first point (point A), which is a sampling distance L behind a point B (curve detection point) on the road line RL ahead of the vehicle, and a curve detection point (point B). An angle formed between a first vector AB from point A to point B and a second vector BC from point B to point C by giving a second point (point C) ahead by a sampling distance L with respect to the first point. θ is calculated as a curvature index at the curve detection point (point B) (see FIGS. 9 and 10).

Next, the routine proceeds to step C3, where the curve judgment means 23 judges a curve. This curve judgment is performed by comparing the above-mentioned curvature index θ with a curve judgment reference curvature index θ _O (θ _O > 0) as a threshold value. If | θ | ≧ θ _O , the curve detection point The process proceeds to step C4 via the YES route. On the contrary, if | θ | <θ _O , it is determined that the road is a straight road, and the flow returns through the NO route.

Then, when the curve of the road is determined in step C3, the start point LS and the end point LE of the curve are set by the curve determination means 23 in step C4. This is because a curve detection point where the curvature index θ becomes | θ | ≧ θ _O from the state of | θ | <θ _O with respect to the curve determination reference curvature index θ _O is set as the curve start point LS, and the curvature index θ is | θ | <θ from the state of | θ | ≧ θ _O
The curve detection point that becomes _O is set as the curve end point LE.

Next, the flow advances to step C5, where the correcting means 2
3A corrects the start point LS and end point LE of the curve. This correction is performed using, for example, a data table as shown in FIG. Then, in step C6, when the curve radius R is calculated using the sampling distance L and the curvature index θ, the process proceeds to step C7, in which the blind curve determination means 24 performs a blind curve calculation. This blind curve calculation is a calculation for determining whether or not the curve determined in step C3 is a blind curve. For example, the following calculation is performed.

That is, the curve angle within the range of the driver's viewing angle at the curve start point LS is defined as the curve depth θB, and the curve depth θB is defined as the distance M from the driver's viewpoint to the roadside, the road width LB, and the curve radius R. Calculate using
Further, the actual curve angle θR is calculated based on the information of the curve start point LS and the end point LE in step C5.

In step C8, based on the result of the blind curve calculation in step C7 described above,
It is determined whether the curve to be detected is a blind curve. This is determined by comparing the above-described curve θB with the actual curve angle θR in the blind curve determination means 24 to determine the actual curve angle θR.
Is larger than the curve depth θB, this curve is determined as a blind curve. Then, when this curve is determined to be a blind curve, the process proceeds through a YES route to step C9, and when it is determined that the curve is not a blind curve, the process returns through a NO route.

Next, in step C9, the continuous curve determination means 26 determines whether or not the curves are continuous. Curve which calculates the curve distance D from two pieces of information start point LS and the end point LE of the curve, which is compared with a threshold value D _0, which is continuous with the curved distance D is smaller than the threshold value D ₀ Is determined. Further, if the distance D is larger than the threshold value D ₀ determines curve alone curve.

After the determination of the continuous curve is performed in step C9, the process proceeds to step C10, where the hairpin curve detecting means 24A determines whether the curve is a hairpin curve. In this hairpin curve detection, for example, if the actual curve angle θR is equal to or more than a predetermined value (for example, 130 °), this curve is determined as a hairpin curve.

After the hairpin curve is detected in step C10, the process returns. 4.3 Vehicle Speed Determination Processing The vehicle speed determination is performed by the determination means 30 as shown in FIG. 34. First, the allowable approach lateral acceleration setting unit 32 sets a lateral acceleration threshold value (allowable approach lateral acceleration) Gy ^* ( Step D10). The lateral acceleration Gy ^* is given to a target lateral acceleration value Gy _th (Gx _th = 0) obtained by a vehicle speed-lateral acceleration correspondence curve used in the trace control system 70 as shown in the following equation.

Gy ^* = Gy _th −K1 (where 0 ≦ K1 ≦ 2) Then, the road width correction means 38A performs a lateral acceleration threshold Gy ^*.
(Step D20), that is, if the road width is large, the allowable approach lateral acceleration Gy ^* is increased, and if the road width is small, the allowable approach lateral acceleration Gy ^* is decreased. Further, the driving characteristic correspondence correction means 38B calculates the supplementary lateral acceleration threshold G
The driving characteristics are corrected for y ^* (step D30). That is,
The higher the driver's crispness, the larger the lateral acceleration Gy ^*, and the lower the driver's crispness (ie, the higher the degree of looseness), the smaller the lateral acceleration Gy ^* .

Further, the navigation error correcting means 38C corrects the lateral acceleration threshold value Gy ^* for the navigation error (step D40). That is, in order to deal with the navigation error, that is, the error of the curve radius calculated based on the navigation information, the allowable approach lateral acceleration Gy ^* is corrected to the decreasing side according to the assumed navigation error. On the other hand, in the expected lateral acceleration calculation unit 34,
Calculating an expected lateral acceleration Gypre (step D50);
That is, the curve radius R detected by the curve detection means 20
And the vehicle speed VB detected by the vehicle speed sensor 84,
The expected lateral acceleration Gypre is calculated from the following equation.

Gypre = VB ² / R Then, the vehicle speed determination section 36 compares the allowable approach lateral acceleration Gy ^* obtained from the allowable approach lateral acceleration setting section 32 and the expected lateral acceleration calculation section 34 with the expected lateral acceleration Gypre. Then, it is determined whether the current vehicle speed VB is too high to enter the curve ahead (step D60). That is, if the following equation holds, it is determined that the current vehicle speed VB is too high to enter the curve ahead.

Gypre> Gy ^{* If the} vehicle speed VB has passed, for example, the vehicle speed VB indicates an excessive speed level such as a small excess (level 1), a medium excess (level 2), and a large excess (level 3).
^* Exceeds V1 (for example, 5 km / h) (step D90), or if the vehicle speed VB exceeds the allowable approach speed V ^* by V
2 (eg, 20 km / h) and then set (step D110).

That is, if the vehicle speed VB exceeds V1 or lower, level 1 (step D100); if the vehicle speed VB exceeds V1 and lower than V1, level 2 (step D120);
If the vehicle speed VB exceeds V2, the level is set to level 3 (step D130). 4.4 Operation of Alarm / Vehicle Speed Control The alarm / vehicle speed control is performed by the non-conforming control means 40. For example, as shown in FIG. 35, first, curve information (continuous curve, hairpin curve, distance between curves), vehicle speed VB,
The speed excess level and map information are read (step E1)
0). Then, it is determined whether or not the target curve is an intersection using the map information (step E12). If the curve is an intersection, the warning / vehicle speed control is not performed.

If the curve is not an intersection, it is determined whether the vehicle speed is equal to or higher than a predetermined value V0 (for example, 30 km / h) (step E20). The vehicle speed is a predetermined value V0 (for example, 30 km / h)
In the following cases, the alarm and the vehicle speed control are not performed. On the other hand, if the vehicle speed is equal to or higher than the predetermined value V0 (for example, 30 km / h), the flag F1 is set to 1
It is determined whether or not (Step E30). This flag F1
Is set to 1 when an alarm is issued for the target curve, and is set to 0 otherwise.

If no alarm has been issued, the process proceeds to step E40, where it is determined whether the vehicle is currently traveling on a curve.
The curve in this case is not the curve to be warned but the curve immediately before it. If the vehicle is not running on a curve, it is determined whether the flag F4 is 1 (step E50). The flag F4 is set to 1 when the target curve is in the alarm prohibition state, and is set to 0 otherwise. The alarm is prohibited within a required traveling distance after an alarm is issued at the first curve of the continuous curve.

If the alarm is not prohibited, it is determined whether or not the flag F3 is 1 (step E60). This flag F3 is
When the vehicle enters the warning / control start distance Lneed, it is set to 1 if the vehicle is traveling on a curve (step E130), and otherwise to 0. If the flag F3 is not 1, alarm control is performed (step E70), and the flag F1 is set to 1 (step E80).

Then, the count value T of the counter is increased by the control period (ΔT) (step E90). The count value T is for counting a time t2 (for example, 2 seconds) from the warning control to the vehicle speed control. When the alarm control is performed in this manner, in the next control cycle, the process proceeds from step E30 to step E92 to determine whether or not the brake pedal is depressed. If the brake pedal is depressed, the flag F2 is set to 0 in step E94.
The control returns without performing the vehicle speed control.

On the other hand, if the brake pedal has not been depressed, the routine proceeds to step E100, where it is determined whether or not the flag F2 is 1. This flag F2 is set to 1 when vehicle speed control is performed on the target curve, and is set to 0 otherwise. If vehicle speed control has not yet been performed,
Proceeding to step E110, the count value T becomes a predetermined value [t2
(For example, 2 seconds)], and determines whether a predetermined value [t
2 (for example, 2 seconds)], the routine returns. If the predetermined value [t2 (for example, 2 seconds)] is reached, step E
Proceed to 120 to perform vehicle speed control.

On the other hand, although the alarm is not prohibited, step E60
If the flag F3 is determined to be 1 in this case, since the distance between the vehicle and the start point of the curve is smaller than Lneed, the process proceeds to step F140, and the distance Lstrait between the curves is set to the predetermined distance L
It is determined whether it is 0 (for example, 20 m) or more. Where L
If the trait is equal to or longer than the predetermined distance L0 (for example, 20 m), the alarm control (step E150) and the vehicle speed control (step E16)
0) are performed, and the flag F1 is set to 1 and F4 is set to 0 (step E170). Lstrait is a predetermined distance L
If it is not 0 (for example, 20 m) or more, neither the warning control nor the vehicle speed control is performed.

On the other hand, when the alarm is prohibited, the process proceeds to step E180, and the traveling distance Lpast of the vehicle after the start of the alarm prohibition is set.
Is counted, and it is determined whether or not the distance Lpast has reached a predetermined value (step E190). When the distance Lpast has reached the predetermined value, the alarm inhibition flag F4 is set to 0 and the alarm inhibition is canceled. Until the distance Lpast reaches a predetermined value, the count value T is updated (step E200). Then, it is determined whether or not the target curve has a hairpin (step E21).
0), if there is no hairpin, alarm prohibition is continued, but if there is a hairpin, alarm control is performed (step E2).
20), the flag F1 is set to 1 (step E23)
0).

Even during the alarm prohibition, the timer T keeps the predetermined value [t
2 (for example, 2 seconds)], vehicle speed control is performed. 4.5 Operation Contents of Alarm Control Alarm control is performed, for example, as shown in FIG. That is, first, it is determined whether or not there is priority navigation information (step F10). Here, first, the last navigation voice information is prioritized. If there is this last navigation voice information, generation of navigation information is instructed (step F70). If there is no navigation information, or if there is navigation information other than the final navigation audio information, the process proceeds to step F20.

Then, it is determined whether or not the target curve is a continuous curve.
Go to F and issue a warning command of a warning message according to the overspeed level. In other words, if the vehicle speed is too small (level 1), a warning message such as "It is a curve ahead." Or "It is a curve. Please be careful." If the vehicle speed is too high (level 3), an alarm will be issued with a message such as "Dangerous. Step on the brakes."

On the other hand, if the target curve is a continuous curve, the process proceeds to step F40, where the alarm stop flag F4 is set to 1, the alarm stop state is set, and the running distance Lpast of the vehicle after the start of the alarm inhibition is counted. Is started (step F50), and the process proceeds to step F60 to issue a warning instruction of a warning message according to the speed excess level. In other words, if the vehicle speed is slightly excessive (level 1), a warning message such as "The curve continues ahead." Or "Continuous curve. Please be careful."
In the case of, a warning message such as "The curve will continue in the future. Please slow down." Will be issued. If the vehicle speed is too large (level 3), "The curve is continuous and it is dangerous. Step on the brake. "Or the like. 4.6 Operation Details of Vehicle Speed Control The vehicle speed control is performed, for example, as shown in FIG. That is, first, it is determined whether or not the accelerator pedal is being depressed (step G10). If the accelerator pedal is being depressed, throttle control is selected. First, it is determined whether a throttle control end condition is satisfied (step G20). That is, it is determined whether any one of the following is satisfied.

Whether the time t3 (for example, 3 seconds) has elapsed since the start of the throttle control? Did the driver indicate his intention to accelerate during throttle control? Was trace control started during throttle control? If the throttle control end condition is not satisfied, step G
At 30, throttle control is performed. In this throttle control, for example, the engine output torque TE with respect to the driver request torque TM is instantaneously reduced by a torque correction coefficient C1 having a characteristic as shown in FIG.
(Seconds) to gradually return to correspond to the driver required torque TM.

If the throttle control end condition is satisfied during the throttle control, the vehicle speed control end flag F2 is set to 1 (step G60), the timer T is reset to 0 (step G70), and the vehicle speed control by the throttle control is ended. I do. On the other hand, unless the accelerator pedal is being depressed
The shift-down control is selected. First, it is determined whether the vehicle speed excess level is equal to or higher than level 2 (step G32), and if not, the shift-down control is not performed. The end flag F2 is set to 1 (step G60), the timer T is reset to 0 (step G70), and the vehicle speed control ends.

If the level is 2 or more, the process proceeds to step G40, where it is determined whether or not the shift speed, which is the shift-down control prohibition condition, is lower than the middle speed (lower than the third speed). If the shift stage is lower than the middle speed stage (third speed stage or lower), the downshift control is not performed, the vehicle speed control end flag F2 is set to 1 (step G60), and the timer T is reset to 0 (step G).
70), the vehicle speed control ends.

If the shift speed is not lower than the middle speed (below the third speed), that is, if the fourth speed or the fifth speed is selected,
Shift down control is performed. (Step G50). In this shift-down control, the vehicle speed VB is less medium speed range (V ₀ below) whether the judge, following mid-speed range the vehicle speed VB is (VB ≦
If V ₀ ), the gear shifts down to the third gear. In other words, the gear shifts down to the third speed both when the current speed is the fifth speed and when the current speed is the fourth speed. Also, the vehicle speed VB is higher than the middle speed range (V
If B> V ₀ ), shift down by one stage. That is,
When the current gear is the fifth gear, the gear is downshifted to the fourth gear, and when the current gear is the fourth gear, the gear is downshifted to the third gear.

When such a shift down command is issued, the vehicle speed control end flag F2 is set to 1 (step G6).
0), reset the timer T to 0 (step G7)
0), the vehicle speed control by the downshift control ends. 5. Effects of the alarm and vehicle speed control of this device The following effects can be obtained by such alarm and vehicle speed control. (1) The navigation system 5 by the curve detecting means 20
Since the road map information of the optimal route obtained during the route guidance of 0 is used, a road to be alerted and the vehicle speed controlled is specified,
The curve situation ahead of the vehicle can be quickly and reliably detected without requiring a huge amount of calculation. Therefore,
Warnings and vehicle speed control can be reliably performed in real time during traveling. (2) When the target curve is an intersection, no warning or vehicle speed control is performed, so that an inconsistent warning that a "curve exists" is not issued to the intersection and the navigation information is obstructed. Not even. Therefore, there is an advantage that the driver can perform an appropriate process through the navigation information without any discomfort at the intersection. (3) Since the curve detection uses the map information of the navigation system and corrects the calculation error accompanying the use of the map information appropriately, the curve situation in front of the vehicle is not required without a huge calculation. Can be accurately detected. Therefore, the warning and the vehicle speed control can be appropriately performed. (4) In the curve detecting means, since a curve having a large curve radius or a curve with good visibility is removed as a curve to be subjected to a warning or a vehicle speed control, a blind curve is set. By performing the vehicle speed control only when the degree of necessity is high, it is possible to prevent the driver from feeling uncomfortable and to expect an effect of enhancing the control effect. (5) Further, since it is determined whether the curve is a continuous curve or a single curve, and an alarm is generated according to the type of the curve, there is an advantage that the driver can take appropriate measures for the curve. (6) When entering a continuous curve, the curve warning and speed control are interrupted only for a certain distance (temporarily prohibited).
Therefore, it is not necessary to issue an alarm for each curve, for example, on a curved road in a mountain area. Therefore, it is possible to avoid unnecessary warnings for curves that are easy for the driver to recognize without issuing a warning for each curve in a continuous curve, and to avoid a situation where the warning becomes noise. (7) Of course, the warning and speed control are interrupted only for a fixed distance, so if a continuous curve is continued for a long time, the warning or speed control is performed at appropriate time intervals. And the conflicting purpose of not making the alarm feel annoying. (8) Further, even when such a curve alarm or speed control is interrupted, if a hairpin curve that is expected to generate a larger lateral acceleration than the previous curve is close, an alarm is issued. Therefore, the interruption of the alarm and the speed control is temporarily stopped, and the alarm and the speed control for the hairpin curve are performed. Therefore, there is an advantage that it is possible to reliably promote safe driving while considering the elimination of discomfort of the driver. (9) Further, the allowable approach lateral acceleration (lateral acceleration threshold value) Gy ^* for determining the vehicle speed excess is corrected according to the road width and the driving characteristics of the driver, so that a sense of discomfort associated with a curve warning or speed control is reduced. That is, if the road width of the curved road is large, the warning or speed control is not performed until a relatively large lateral acceleration occurs, and if the road width of the curved road is small, the warning or the speed control is performed at the stage where the relatively small lateral acceleration occurs. , The control is adapted to the driver's feeling. Also,
Based on the driving characteristics of the driver, the curve warning and the speed control are performed at threshold values corresponding to the individual characteristics of each driver, and the control is adapted to the feeling of each driver. (10) Even if an error occurs in the curve radius R calculated from the error in the navigation information, the lateral acceleration threshold value Gy is compensated by the error.
^{Since *} is corrected (navigation correction), it is possible to avoid a situation in which the originally required alarm or control is not executed due to such an error. In the case of danger, the curve warning and the speed control are surely performed. (11) An error may also occur in the control start point based on the warning / control start distance Lneed due to an error in the navigation information. In this case, too, the error is taken into consideration so that there is no control delay. The warning / control start distance Lneed is set according to the vehicle speed so as to suppress the contradictory start of the control too early while taking into account the above, so that a warning or vehicle speed control can be performed at an appropriate timing when entering a curve. (12) At the time of route guidance, the last navigation voice information is given priority first, and then the curve information is prioritized over the order of the navigation information other than the last voice information. The final navigation audio information at the right time,
The original performance of route guidance can be reliably exhibited. In addition, since the curve information has priority over the order of other navigation information having relatively low importance, warning of the curve can be reliably promoted. (13) Since the type of the curve warning is provided according to the degree of excess of the vehicle speed, the driver can be prompted to perform appropriate processing, and the effect of the curve warning is enhanced. (14) In the case of vehicle speed control, if the driver has an intention to request engine torque (that is, the accelerator pedal is depressed), the vehicle speed is controlled by limiting the engine torque by throttle control, otherwise, the vehicle speed is controlled by downshifting. Is performed, deceleration control can be performed reliably. (15) Further, the throttle control and the shift-down control are not performed simultaneously, and the throttle control is terminated for a time limit [t3 (for example, 3 seconds)] and the shift-down control ends when the vehicle speed falls to a vehicle speed corresponding to the shift-down position. However, this deceleration does not become excessive, but rather is based on the effect of warning the driver rather than the effect of reducing the vehicle speed. That is, the vehicle speed control can be performed at the driver's will, and a warning can be given to the curve without giving the driver any discomfort. (16) Further, since the vehicle speed control is performed after a time from the curve warning, if the driver expresses his intention to decelerate during this time, unnecessary vehicle speed control is avoided, and the vehicle speed control by the driver's will is not hindered. 6. Others (a) In the present embodiment, the vehicle speed control is intended to provide a warning effect to the driver rather than to reduce the actual vehicle speed. The vehicle speed may be reduced. In this case, it is conceivable to selectively use the vehicle speed control for the purpose of reducing the actual vehicle speed and the vehicle speed control for the purpose of warning the driver according to the conditions. (B) In the above-described embodiment, for a curve requiring special attention, such as a hairpin curve, an alarm is issued if the vehicle speed is high even when the alarm control is interrupted. The warning may be issued at a required timing based on the warning / control start distance Lneed regardless of the vehicle speed, that is, even if the vehicle speed is not particularly high. As a result, it is possible for a driver who is driving safely to cope with a hairpin curve or the like with a margin. (C) Furthermore, the control device for the road condition in front of the vehicle may be configured by using only the main parts of the above embodiment. For example, various processes caused by errors in the navigation information can be omitted if the errors in the navigation information become small and can be ignored. (D) In the present embodiment, both the alarm and the vehicle speed control are used as appropriate, but a configuration using only one of them is also conceivable.

[0216]

As described above in detail, according to the control device for road conditions ahead of a vehicle according to the first aspect of the present invention, if a curve exists on the road ahead of the vehicle, the curve detecting means detects the curve. And determining means for determining whether the current speed of the vehicle is too high when entering the curve when the curve is detected by the curve detecting means, and determining the vehicle speed based on the determination result of the determining means. When the vehicle speed is determined to be too high, an alarm is generated or a non-conforming-time control means for controlling the running state of the vehicle is provided. Determining a first point on the road line that is a sampling distance behind the curve detection point on the front road line and a second point on the road line that is ahead of the curve detection point by the sampling distance;
Curvature index calculation for calculating a curvature index at a curve detection point based on an angle between a first vector from the point to the curve detection point and a second vector from the curve detection point to the second point Means, comparing the curvature index calculated by the curvature index calculation means with a curve determination reference curvature index, and when the curvature index is larger than the curve determination reference curvature index, the curve detection point is curved. Determining and detecting a curve start point on a road line in front of the vehicle based on the curvature index calculated by the curvature index calculation means, and determining the sampling distance according to a curvature radius of the curve. It has a sampling distance setting means for setting, and the nonconforming control means controls the generation of the above-mentioned alarm or the control of the running state based on the curve start point information detected by the curve judgment means. The curve determining means corrects the position of the curve start point detected based on the curvature index so as to correspond to the error of the curve start point caused by the setting of the sampling distance. With the configuration in which the correction means is provided, the curve situation ahead of the vehicle can be accurately detected without requiring enormous calculations, and a warning and vehicle speed control can be appropriately performed at an accurate timing.

According to a second aspect of the present invention, in addition to the configuration of the first aspect, the correction means may determine whether the curve has a relaxation curve. Alternatively, the configuration in which different corrections are performed depending on a curve having no relaxation curve has an advantage that correction can be performed in accordance with a curve condition of a road. According to a third aspect of the present invention, in addition to the configuration of the first aspect, the correction means includes a correction value corresponding to a preset curve radius. The configuration in which the correction is performed based on the data table has an advantage that the correction value can be calculated easily and in a short time.

According to a fourth aspect of the present invention, in addition to the configuration of the third aspect, the correction means includes a curve which is not set in the data table. When the radius curve is corrected, the correction value is calculated by first-order complementing the correction value set in the data table.
There is an advantage that correction of a curve having a curve radius not set in the data table can be easily and quickly corrected.

According to a fifth aspect of the present invention, in addition to the structure of any one of the first to fourth aspects, the curve detecting means includes:
With the configuration of detecting the curve based on the road information stored in the navigation system, it is possible to issue a warning or to specify in advance the road on which the vehicle speed is to be controlled, and it is possible to determine the curve situation ahead of the vehicle without requiring enormous calculations. Detection can be performed quickly and reliably. Therefore, there is an advantage that vehicle speed control can be reliably performed in real time during traveling.

According to the control device for a road condition ahead of a vehicle according to the present invention described in claim 6, in addition to the configuration described in claim 1, the running state control of the vehicle by the nonconforming control means is performed by: With the configuration of deceleration control of the vehicle, when the vehicle speed is too high, it is possible to make the driver recognize that the vehicle speed is excessive from the sense of speed, and to assist the actual deceleration of the vehicle.

According to a seventh aspect of the present invention, in addition to the structure described in the sixth aspect, the deceleration control further includes an output of an engine mounted on the vehicle. By the configuration that is performed by control,
When the vehicle speed is too high, it is possible to easily realize that the driver recognizes that the vehicle speed is excessive and assists in actually decelerating the vehicle.

Further, according to the control device for road condition in front of an automobile according to the present invention, the above-mentioned claim 6 or 7 is provided.
In addition to the configuration described above, the deceleration control is performed by the downshift control of the automatic transmission mounted on the vehicle, so that when the vehicle speed is too high, the vehicle speed is transmitted to the driver instead of the engine output control. Can be easily realized to recognize that the vehicle speed is excessive, or to assist the actual deceleration of the vehicle.

According to the ninth aspect of the present invention, in addition to the configuration of the seventh aspect , the deceleration control includes a time period for warning the existence of the curve. With the configuration of being limited , the driver can be more reliably notified of the presence of the curve by the alarm and the deceleration control. And this deceleration is excessive
Rather than dryness
Driver, because the main effect is to warn the driver
Give a warning about curves without causing discomfort to
Can be.

[Brief description of the drawings]

FIG. 1 is a block diagram showing a control device for a road condition in front of an automobile as an embodiment of the present invention.

FIG. 2 is a configuration diagram illustrating a navigation system related to a control device for a road in front of a vehicle according to an embodiment of the present invention;

FIG. 3 is a configuration diagram showing a trace control system related to a control device for a road condition ahead of a vehicle as one embodiment of the present invention;

FIG. 4 is a diagram showing a vehicle speed-lateral acceleration correspondence map related to the control device for a road condition ahead of an automobile as one embodiment of the present invention;

FIG. 5 is a diagram for explaining estimation of a road traffic condition related to the control device for a road condition ahead of a vehicle as one embodiment of the present invention;

FIG. 6 is a diagram for explaining the estimation of driving characteristics related to the control device for a road condition ahead of a vehicle as one embodiment of the present invention.

FIG. 7 is a schematic block diagram for explaining curve detection in the control device for a road condition ahead of a vehicle as one embodiment of the present invention.

FIG. 8 is a diagram showing an area of a curve to be detected by a curve detecting means of the control device for a road ahead in accordance with an embodiment of the present invention;

FIG. 9 is a diagram for explaining calculation of a curve angle in a curve detection unit of the control device for a road ahead in a vehicle as one embodiment of the present invention;

FIG. 10 is a diagram for explaining calculation of a curve angle and a sampling distance in a curve detecting means of the control device for road condition ahead of a vehicle as one embodiment of the present invention;

FIG. 11 is a diagram for explaining correction of a curve start point in a curve detecting means of the vehicle front road condition correspondence control device as one embodiment of the present invention, and is a diagram illustrating a curve start point of a curve without a transition curve; It is a figure explaining a correction.

FIG. 12 is a diagram for explaining correction of a curve start point in a curve detection unit of a vehicle front road condition correspondence control device as one embodiment of the present invention, and is a diagram illustrating a curve start point of a curve having a transition curve; It is a figure explaining a correction.

FIG. 13 is a data table for correcting a curve start point according to a curve radius in a curve detecting means of a road condition handling control device for a vehicle according to an embodiment of the present invention. It is a data table.

FIG. 14 is a data table for correcting a curve start point according to a curve radius in a curve detecting means of a vehicle front road condition correspondence control device as one embodiment of the present invention. It is a data table.

FIG. 15 is a schematic diagram for explaining a curve depth of a blind curve in a curve detecting means of the control device for a road ahead in accordance with an embodiment of the present invention.

FIG. 16 is a diagram showing an area of a blind curve to be controlled by a curve detecting means of the control device for a road ahead in accordance with an embodiment of the present invention;

FIG. 17 is a graph showing the degree of variation between the actual curve depth and the curve depth obtained from the navigation information in the curve detecting means of the vehicle front road condition control device as one embodiment of the present invention.

FIG. 18 is a diagram for explaining a method of determining a continuous curve in the curve detecting means of the control device for a road ahead in accordance with an embodiment of the present invention.

FIG. 19 is a diagram illustrating setting characteristics of an allowable approach lateral acceleration (lateral acceleration threshold value) used in the control device for a road ahead in a vehicle as one embodiment of the present invention.

FIG. 20 is a diagram illustrating characteristics of a road width corresponding correction of an allowable approach lateral acceleration used in a vehicle front road condition corresponding control device as one embodiment of the present invention.

FIG. 21 is a diagram illustrating a characteristic of a correction of a driving characteristic corresponding to an allowable approach lateral acceleration used in a control device for a road ahead in a vehicle as one embodiment of the present invention.

FIG. 22 is a diagram illustrating an error in navigation information used in the control device for a road ahead of a vehicle as one embodiment of the present invention.

FIG. 23 is a diagram illustrating a correction for a curve radius error (navi error correction) caused by an error in navigation information used in a control device for road condition ahead of a vehicle as one embodiment of the present invention.

FIG. 24 is a diagram showing characteristics of a correction (navi error correction) for a curve radius error of an allowable approach lateral acceleration used in a control device for a road ahead in a vehicle as an embodiment of the present invention.

FIG. 25 is a graph showing a correlation between a curve approaching speed and a braking start position in a curve detecting means of the control device for a road ahead in a vehicle as one embodiment of the present invention.

FIG. 26 is a graph showing a relationship between a vehicle speed and a control start distance in a curve detecting means of the control device for a road ahead in accordance with an embodiment of the present invention;

FIG. 27 is a graph for explaining calculation of a required distance for minimum braking by the curve detecting means of the control device for a road in front of the vehicle as one embodiment of the present invention .

FIG. 28 is a graph showing an error-corrected control start distance in the curve detecting means of the control device for a road ahead in a vehicle as one embodiment of the present invention.

FIG. 29 is a diagram schematically showing an example of optimum route information from navigation information used in the control device for road condition ahead of a vehicle as one embodiment of the present invention.

FIG. 30 is a diagram showing a logic of an alarm control by the control device for a road ahead condition according to an embodiment of the present invention;

FIG. 31 is a diagram showing characteristics of throttle control by the control device for a road condition ahead of a vehicle as one embodiment of the present invention.

FIG. 32 is a flowchart showing the overall operation of the control device for a road condition ahead of a vehicle as one embodiment of the present invention.

FIG. 33 is a flowchart showing a curve detecting operation of the control device for a road condition in front of a vehicle as one embodiment of the present invention.

FIG. 34 is a flowchart showing a vehicle speed determination operation of the control device for a road ahead condition according to an embodiment of the present invention;

FIG. 35 is a flowchart showing a warning / vehicle speed control operation of the control device for a road ahead in accordance with an embodiment of the present invention.

FIG. 36 is a flowchart showing an alarm control operation of the control device for a road condition ahead of a vehicle as one embodiment of the present invention.

FIG. 37 is a flowchart showing a vehicle speed control operation of the control device for a road condition ahead of an automobile as one embodiment of the present invention.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 10 Front road condition control apparatus 20 Curve detecting means 21 Sampling distance setting means 22 Curvature index calculating means 23 Curve determining means 23A correction means 24 Blind curve determining means 25 Control target curve selecting means 26 Continuous curve determining means 27 Hairpin curve detecting means 30 Judging means 32 Permissible approach lateral acceleration setting section 34 Expected lateral acceleration calculating section 36 Vehicle speed judging section 38A Road width corresponding correcting means 38B Driving characteristic corresponding correcting means 38C Curve radius error corresponding correcting means 40 Non-conforming control means 42 Alarm / control start determining means 42A Alarm / control start distance setting section 42B Alarm / control start determination section 44 Alarm means (voice information control means) 46 Vehicle speed control means as throttle opening / automatic transmission control means (throttle / AT control means) 50 Automotive navigation System 52 52 Road map information storage means 54 Input switch (data input means) 56 Current position estimation means 58 Optimal route selection / storage means 60 Screen information control means 62 Navigation voice control means 70 Traction control system (trace control system) 71 Traction control switch 72 Target lateral acceleration calculating means 74 Target longitudinal acceleration setting means 76A Torque conversion means 76B Clip means 76C Target throttle opening setting means 78 Driving characteristic estimating means 78A Road traffic condition estimating means 80 Steering angle sensor 82 GPS receiver 84 Vehicle speed sensor 86 Geomagnetism Sensor 88 Gyro compass 90 Display 92 Sound information generating means 94 Throttle driving means 96 ECU (electronic control unit) for automatic transmission

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI G08G 1/09 G08G 1/09 CS V 1/0969 1/0969 G09B 29/00 G09B 29/00 A (56) References Special JP-A-4-236699 (JP, A) JP-A-5-141979 (JP, A) JP-A-6-36187 (JP, A) (58) Fields investigated (Int. Cl. ⁷ , DB name) G08G1 / 16 B60K 28/10 B60K 41/00 F02D 29/02 G01C 21/00 G08G 1/09-1/0969

Claims (9)

(57) [Claims] 1. A curve detecting means for detecting a curve on a road ahead of a vehicle when the curve exists, and a current speed of the vehicle when entering the curve when the curve is detected by the curve detecting means is increased. Determining means for determining whether or not the vehicle speed is too long; and non-conforming control means for issuing an alarm or controlling the running state of the vehicle when it is determined that the speed of the vehicle is too high based on the determination result of the determining means The road condition handling control device for a vehicle, comprising: a first point on the road line that is a sampling distance behind a curve detection point on a road line in front of the vehicle; A first point from the first point to the curve detection point and a second vector from the curve detection point to the second point. A curvature index calculating means for calculating a curvature index at the curve detection point based on the angle, and comparing the curvature index calculated by the curvature index calculation means with a curve judgment reference curvature index to determine the curvature index of the curve. When the curve detection point is larger than the determination reference curvature index, it is determined that the curve detection point is curved, and a curve start point on a road line in front of the vehicle is determined based on the curvature index calculated by the curvature index calculation means. A curve determining means for detecting, and a sampling distance setting means for setting the sampling distance in accordance with a radius of curvature of the curve, wherein the non-conforming control means based on the curve start point information detected by the curve determining means. The above-mentioned alarm is generated or the running state is controlled. So as to correspond to, characterized in that the correction means for correcting the position of the curve starting point is detected based on the curvature index is provided, the front road conditions corresponding control device of the motor vehicle. 2. The vehicle according to claim 1, wherein said correction means is configured to perform different corrections depending on whether the curve has a transition curve or a curve without a transition curve. Control device for road conditions ahead. 3. The vehicle according to claim 1, wherein said correction means performs the correction based on a data table of correction values corresponding to a preset curve radius. Control device for road conditions ahead. 4. When the correction means corrects a curve having a curve radius not set in the data table, the correction value is calculated by first-order complementing the correction value set in the data table. 4. The control device according to claim 3, wherein the control device is configured to perform the following. 5. The system according to claim 1, wherein the curve detecting means is configured to detect the curve based on road information stored in a navigation system.
5. The control device for road condition in front of a vehicle according to any one of claims 1 to 4. 6. The control device according to claim 1, wherein the running state control of the vehicle by the nonconforming control means is deceleration control of the vehicle. 7. The vehicle according to claim 7, wherein the deceleration control is performed by controlling an output of an engine mounted on the vehicle.
7. The control device according to claim 6, which is adapted to a road condition ahead of the vehicle. 8. The control device according to claim 6, wherein the deceleration control is performed by a shift-down control of an automatic transmission mounted on the vehicle. 9. deceleration control, characterized in that it is time limited in order to warn of the presence of the curve, the front road conditions corresponding vehicle control unit as claimed in claim 7 wherein.