JP5310674B2 - Vehicle behavior control device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a vehicle behavior control device capable of performing deceleration control matching with a sense of danger of a driver not only upon entering a curve but also in the curve. <P>SOLUTION: When it is determined that an own-vehicle is positioned in a curve, in the deceleration control, a second correction target relative speed calculation expression obtained by correcting a first correction target relative speed calculation expression based on an approach/separation state evaluation index KdB on the basis of a difference between a proper road boundary distance and an in-curve proper road boundary distance is used to calculate a second correction target relative speed. <P>COPYRIGHT: (C)2012,JPO&amp;INPIT

Description

  The present invention relates to a vehicle behavior control device, and more particularly, to a device that performs vehicle behavior control when entering a curve and traveling in a curve.

  Using the approaching / separating state evaluation index obtained by determining the approaching / separating state of the vehicle with respect to the object in front of the own vehicle based on the temporal change rate of the apparent area of the front object projected on the driver's retina Devices for performing vehicle speed control are known.

  Patent Document 1 discloses a vehicle speed control device that can execute deceleration control that matches the driver's sense of danger when entering a curve using this approach / separation state evaluation index. Specifically, in the vehicle speed control device disclosed in Patent Document 1, the approach / separation state evaluation index (corrected approach / separation state evaluation index) in consideration of the curve-time target passing speed Vr_Gy_offset in determining the deceleration control start timing before the curve. When the current value KdB_c (a) _p exceeds the threshold KdB_c_t determined from the approximate expression (brake discriminant KdB_c (a)) of the corrected approach / separation state evaluation index KdB_c (a) By setting as the deceleration control start time, it is possible to start the deceleration control at a timing that matches the driver's feeling when attempting to pass the curve at the curve target passing speed Vr_Gy_offset.

JP 2010-30403 A

  The vehicle speed control device disclosed in Patent Document 1 is intended to decelerate to a speed at which a curve of a certain curve R (curvature radius of curvature) can be bent up to the curve entrance at the straight line portion before the curve. Thus, it is effective for the deceleration control under the condition that the curve R after the entrance of the curve is constant.

  However, in the curve where the curve R becomes steeper than the initial target curve R after entering the curve even if the deceleration to a speed at which the curve R can be bent by the curve entrance is completed. If the vehicle is not further decelerated, there is a problem that the curve cannot be bent and deviates outside the curve.

  In addition, if the road surface before and after the entrance of the curve is in a low μ state due to freezing, even if you start deceleration to a speed at which you can turn a certain curve R by the straight line before the curve, If the vehicle does not decelerate to the speed at which the curve R can be turned before the entrance of the curve, the vehicle enters the curve. If the vehicle does not decelerate further, the curve cannot be completely bent and deviates to the outside of the curve.

  In other words, the vehicle speed control device disclosed in Patent Document 1 has a problem that deceleration control that matches the driver's danger may not be executed in the curve.

  The present invention has been made in view of the above-described conventional problems, and an object thereof is a vehicle behavior capable of executing deceleration control that matches a driver's sense of danger not only when entering a curve but also within a curve. It is to provide a control device.

  According to the vehicle behavior control device of the first aspect, when the vehicle inside / outside determination means determines that the vehicle is located outside the curve, the vehicle is based on the target deceleration calculated by the first target deceleration calculation means. On the other hand, if it is determined that the host vehicle is located within the curve, the host vehicle deceleration control is executed based on the target deceleration calculated by the second target deceleration calculating means.

  Specifically, a correction approach / separation state evaluation index that takes into account the target passing speed at the time of a curve is used to determine whether to start deceleration control before the curve. The time when the threshold value determined from the equation is exceeded is set as the deceleration control start time. Therefore, the deceleration control can be started at a timing that matches the driver's feeling when attempting to pass the curve at the curve target passing speed.

  And in deceleration control, deceleration control is performed based on the 1st correction target relative speed calculated using the correction target relative speed calculation formula memorize | stored in the 1st memory | storage means. This corrected target relative speed calculation formula is based on an approach / separation state evaluation index, and it has already been recognized by academic societies and the like that the approach / separation state evaluation index is an index that well indicates the driver's sense of danger. Therefore, by performing deceleration control based on the first corrected target relative speed calculated using the corrected target relative speed calculation formula, smooth control suitable for the driver's sense of danger can be performed.

  Moreover, the straight line part of the road just before the curve ends because the entrance of the curve is the target of the approach / separation state evaluation index and deceleration control is performed so that the target relative speed at the entrance of the curve becomes the target passing speed at the time of the curve. However, when entering the curve portion (that is, the curve portion), there is no inflection point of the speed, and the vehicle can run smoothly. In addition, when the curve R (curvature radius of curvature) of the target curve is constant, even after entering the curve, the vehicle can smoothly travel within the curve without deviating outside the curve.

  On the other hand, in the deceleration control within the curve, the deceleration control is performed based on the second corrected target relative speed calculated using the in-curve corrected target relative speed calculation formula stored in the second storage unit. This in-curve corrected target relative speed calculation formula is based on the approach / separation state evaluation index, and is corrected based on the difference between the appropriate road boundary distance and the appropriate road boundary distance in the curve. Therefore, by performing the deceleration control based on the second corrected target relative speed calculated using the in-curve corrected target relative speed calculation formula, smooth control suitable for the driver's danger can be performed.

  For example, even when the curve R of the target curve is not constant and changes to a larger curve R in the middle of the curve, the road outer boundary located in front of the host vehicle is the target of the approach / separation state evaluation index. The deceleration control is performed so that the target relative speed becomes the target passing speed in the curve when the distance from the front end of the vehicle to the outer boundary of the road is the appropriate road boundary distance in the curve. Therefore, even when the curve changes to a larger curve R in the middle of the curve and the actual road boundary distance becomes smaller than the appropriate road boundary distance in the curve, the actual road boundary distance becomes smaller than the appropriate road boundary distance in the curve. Accordingly, the deceleration control is performed so that the target relative speed is also reduced. Therefore, even when the curve R becomes large in the middle of the curve, it is not necessary to deviate to the outside of the curve, and smooth deceleration control suitable for the driver's danger can be performed.

  Furthermore, the road surface before the entrance of the target curve is low μ due to freezing or the like, and even if deceleration control is performed based on the first corrected target relative speed calculated using the corrected target relative speed calculation formula, Even when the vehicle cannot decelerate to the target speed at the time of the curve before the entrance of the curve, the road outer boundary located in front of the vehicle is the target of the approach / separation state evaluation index, and the distance from the vehicle tip to the road outer boundary is The deceleration control is performed so that the target relative speed in the case of the appropriate road boundary distance in the curve becomes the target passing speed in the curve. Therefore, even if the vehicle cannot be decelerated to the target passing speed at the time of entering the curve and enters the curve in an understeer state, the target relative speed is also reduced by the amount that the actual road boundary distance becomes smaller than the appropriate road boundary distance. Deceleration control is performed so as to decrease. Therefore, even if you enter the curve above the target speed at the time of the curve and become understeered, you do not need to deviate to the outside of the curve and you can perform smooth deceleration control that matches the driver's sense of danger. become.

  Further, according to the configuration of the second aspect, since the evaluation index calculating means calculates the corrected approaching / separating state evaluation index from the equation (1), it is possible to calculate the corrected approaching / separating state evaluation index with a simple formula. Thus, it is possible to more easily realize a vehicle behavior control apparatus that can execute deceleration control that matches the driver's sense of danger not only when entering a curve but also within the curve.

KdB_c(a)：補正接近離間状態評価指標
Vr_Gy_A：第１速度差算出手段が算出する速度差
a：定数
Vr_Gy_offset₀：カーブ時目標速度設定手段が設定するカーブ時目標通過速度
Ds：距離取得手段が取得するカーブ入口到達距離
また、請求項３の構成によれば、実外側曲率半径、適正旋回半径、適正道路境界距離のいずれについても、位置検出センサによって検出される道路境界または道路付帯物（以下、道路境界等）の位置から算出できることになる。また、実道路境界距離も位置検出センサによって検出される道路境界等の位置から算出できることになる。そのため、装置構成を簡素化することができ、且つ、処理も比較的簡易となる。さらに、自車前方に位置する３つの基準点を検出し、それら３つの基準点と自車との距離から実外側曲率半径を算出することで、外側曲率半径を精度よく算出することができる。

KdB_c (a): Corrected approach / separation state evaluation index
Vr_Gy _A : Speed difference calculated by the first speed difference calculation means
a: Constant
Vr_Gy_offset ₀ : Curve target speed set by the curve target speed setting means
Ds: curve entrance arrival distance acquired by the distance acquisition means According to the configuration of claim 3, the road boundary detected by the position detection sensor for any of the actual outer radius of curvature, the appropriate turning radius, and the appropriate road boundary distance. Alternatively, it can be calculated from the position of a road accessory (hereinafter referred to as a road boundary). Also, the actual road boundary distance can be calculated from the position of the road boundary or the like detected by the position detection sensor. Therefore, the apparatus configuration can be simplified, and the process is relatively simple. Furthermore, by detecting three reference points located in front of the host vehicle and calculating the actual outer radius of curvature from the distance between the three reference points and the host vehicle, the outer radius of curvature can be calculated with high accuracy.

  According to the fourth aspect of the present invention, since the position of the road boundary or the like actually detected by the position detection sensor is used as the information for determining whether or not the steering angle is appropriate, the road shape is determined based on the map information. Therefore, the suitability of the steering angle can be determined more accurately than the suitability of the steering angle based on the determined road shape.

  Further, if the steering angle is controlled as in claim 5, the traveling track of the own vehicle can be set to an appropriate turning radius according to the curvature radius of the road.

1 is a block diagram showing a schematic overall configuration of a driving support system 100. FIG. It is a figure explaining the outside curvature radius Re and the appropriate turning radius Re-L. 4 is a flowchart for explaining an example of a deceleration control process executed by a vehicle control ECU 12; (A) is a figure which shows the timing which starts deceleration control, (b) is a figure which shows the relationship between the present value KdB_p of the approaching / separating state evaluation index KdB and the target approaching / separating state evaluation index KdB_t, (c) is a graph showing changes in first corrected target relative speed Vr _{_Gy} _t_after _0. It is a diagram illustrating a change in the second corrected target relative speed Vr _{_Gy} _t_after _n. It is a figure explaining an example at the time of the own vehicle approaching into the curve with a constant curvature at the curve target passing speed Vr_Gy_offset ₀ . It is a schematic diagram for explaining deceleration control when the curve R changes from small to large in the middle of the curve. FIG. 10 is a schematic diagram for explaining deceleration control when the vehicle cannot be decelerated to the curve target passing speed Vr_Gy_offset ₀ by the low μ road before the curve entrance until the curve entrance. It is a diagram illustrating a vehicle of the curve within the appropriate road boundary distance Dc _n in passing through the curve. It is a figure which shows the state from which the vehicle deviates from the turning track | truck of the appropriate turning radius Re-L in a curve. 5 is a flowchart for explaining an example of steering control-related processing executed by a vehicle control ECU 12; It is a flowchart which shows an example of the flow of steering angle control.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. In addition, this embodiment demonstrates the case where the vehicle behavior control apparatus of this invention is applied to a driving assistance system. In FIG. 1, the whole structure of the driving assistance system 100 of this embodiment is shown. As shown in FIG. 1, the driving support system 100 includes a VSC_ECU 1, a rudder angle sensor 2, a G sensor 3, a yaw rate sensor 4, an ENG_ECU 5, an EPS_ECU 6, an EPS actuator 7, a road-to-vehicle communication device 8, a radar 9, an operation SW 10, and a navigation device. 11 and the vehicle control ECU 12. The VSC_ECU 1, the steering angle sensor 2, the G sensor 3, the yaw rate sensor 4, the ENG_ECU 5, the EPS_ECU 6, and the vehicle control ECU 12 are connected to each other via an in-vehicle LAN that complies with a communication protocol such as CAN (controller area network). Hereinafter, a vehicle equipped with the driving support system 100 is referred to as a host vehicle. The driving support system 100 corresponds to the vehicle behavior control device in the claims.

The VSC_ECU 1 controls a brake actuator (not shown) that applies a braking force to the host vehicle, and has a control function of VSC (Vehicle Stability Control (registered trademark)) that suppresses a side slip of the host vehicle. The VSC_ECU 1 receives information on the target deceleration from the in-vehicle LAN, and controls the brake actuator so that the target deceleration is generated in the host vehicle. Further, the VSC_ECU 1 transmits information on the speed (vehicle speed) Vs ₀ of the own vehicle and the brake pressure to the in-vehicle LAN. The steering angle sensor 2 is a sensor that detects information on the steering angle (hereinafter, steering angle) of the steering of the host vehicle, and transmits information on the detected steering angle to the in-vehicle LAN.

  The G sensor 3 is an acceleration sensor that detects acceleration (front-rear G) generated in the front-rear direction of the host vehicle and acceleration (lateral G) generated in the lateral (left-right) direction. Is transmitted to the in-vehicle LAN. The yaw rate sensor 4 is a sensor that detects an angular velocity (yaw rate) about the vertical axis of the host vehicle, and transmits information on the detected yaw rate to the in-vehicle LAN.

  The ENG_ECU 5 receives target acceleration information from the in-vehicle LAN, and controls a throttle actuator (not shown) so that the host vehicle generates the target acceleration. The EPS_ECU 6 controls the steering angle by operating the EPS actuator 7. The EPS actuator 7 is a mechanism that changes the steering angle based on a command signal from the EPS_ECU 6, and includes, for example, a reduction gear that rotates integrally with the intermediate shaft and a motor that rotates the reduction gear.

  The road-to-vehicle communication device 8 is a wireless communication device that performs road-to-vehicle communication with a road-side communication device (road-side infrastructure) installed on a road. When a road ahead in the traveling direction of the host vehicle curves, the entrance of the curve At a point sufficiently before the point, the radius of curvature of the curve (curve R), the friction coefficient μ of the road surface, the coordinates of the entrance / exit point of the curve (latitude and longitude), the width of the curve, the number of lanes, the width of each lane, etc. Receive curve information. For this road-to-vehicle communication, DSRC (Dedicated Short Range Communication) is adopted.

  For example, the radar 9 irradiates a predetermined range in front of the own vehicle with laser light, receives the reflected light, and a distance (hereinafter referred to as a road accessory) provided at or near the road boundary of the curve in front of the own vehicle. The actual road boundary distance D), the deviation amount (lateral deviation amount) between the center axis of the own vehicle width and the center axis of the preceding vehicle, etc. are detected and output to the vehicle control ECU 12. The road accessory is, for example, a reflector, a delineator, or the like that exhibits a reflected light intensity that is greater than or equal to a predetermined intensity with respect to laser light emitted from a vehicle. The radar 9 is assumed to have a detection range in the vehicle width direction that is longer than the length in the vehicle width direction, for example. The radar 9 corresponds to a position detection sensor in claims.

  The operation SW 10 is a switch group operated by the driver of the own vehicle, and operation information of the switch group is output to the vehicle control ECU 12. The navigation device 11 includes a well-known geomagnetic sensor, a gyroscope, a distance sensor, and a GPS receiver for GPS (Global Positioning System) that detects the position of the vehicle based on radio waves from a satellite. A position detection unit, a road map data storage unit for storing road map data, a color display using a liquid crystal or a CRT, and a control circuit.

  The road map data includes link data and node data for representing roads on the map by links and nodes. The link data and node data include, for example, link start and end coordinates, link length, and traffic classification. Information on width, road width, road curvature radius, etc. is included.

  In addition, the navigation device 11 receives a command from the vehicle control ECU 12, specifies the coordinates (latitude and longitude) of the current position of the own vehicle, and exists within a predetermined distance in front of the road at the current position of the own vehicle and the own vehicle. Link data and node data of the curved road to be output.

  The vehicle control ECU 12 is mainly configured as a microcomputer, and each includes a known CPU, ROM, RAM, I / O, and a bus connecting them.

The vehicle control ECU 12 determines whether the host vehicle is sequentially located outside the curve or inside the curve at a predetermined cycle during traveling of the host vehicle. In addition, the determination of whether the vehicle is located outside the curve or inside the curve (hereinafter referred to as curve inside / outside determination) is provided on the road boundary outside the curve from or near the entrance of the curve (straight line end position). This is performed by calculating the distance to the road accessory (hereinafter referred to as appropriate road boundary distance Dc ₀ ) and comparing the appropriate road boundary distance Dc ₀ with the actual road boundary distance D. First, a method for calculating the appropriate road boundary distance Dc ₀ will be described. In the following, a road accessory provided at or near the road boundary outside the curve is referred to as a road outer boundary.

This appropriate road boundary distance Dc ₀ is calculated by equation (7). L is the lateral position of the vehicle center with respect to the lane, and RL is the appropriate turning radius of the vehicle when traveling on a curve. Therefore, the vehicle control ECU 12 corresponds to the turning radius calculating means and the appropriate distance calculating means. This lateral position is determined based on the width, the number of lanes, and the vehicle traveling lane when the navigation device 11 can determine the width, the number of lanes, and the own vehicle traveling lane. Further, when the lateral displacement amount with respect to the preceding vehicle can be determined by the radar 9, the lateral position of the preceding vehicle is determined using the radar 9 or the like, and the lateral displacement amount with respect to the lateral position of the preceding vehicle and the preceding vehicle can be determined. Good. Further, for example, R may be configured to use data acquired by the road-to-vehicle communication described above. Further, as R, an outer curvature radius Re described later may be used.

次に、カーブ内外判定について説明する。カーブ内外判定では、適正道路境界距離Dc₀と実道路境界距離Dとを比較し、D＞Dc₀であった場合には、自車がカーブ外に位置すると判定する。また、D＞Dc₀でなかった場合には、自車がカーブ内に位置すると判定する。これは、D＝Dc₀の場合に自車がカーブの入口に到達することを利用している。

Next, the curve inside / outside determination will be described. In the curve inside / outside determination, the appropriate road boundary distance Dc ₀ is compared with the actual road boundary distance D. If D> Dc ₀ , it is determined that the vehicle is located outside the curve. If D> Dc ₀ is not satisfied, it is determined that the vehicle is located within the curve. This utilizes the fact that the vehicle reaches the entrance of the curve when D = Dc ₀ .

  Further, the vehicle control ECU 12 stores a storage means such as a ROM when the current value KdB_c (a) _p of the corrected approach / separation evaluation index KdB_c (a) exceeds the threshold KdB_c_t on the brake discriminant at the start of deceleration control. Deceleration control is executed using the corrected target relative speed calculation formula stored in (1). Here, the corrected target relative speed calculation formula includes a first corrected target relative speed calculation formula when the host vehicle is located outside the curve and a second corrected target relative speed calculation formula when the host vehicle is positioned within the curve. Assume that two types are stored in advance in the storage means. The brake discriminant is equivalent to the threshold value calculating formula in the claims, the first corrected target relative speed calculating formula is equivalent to the corrected target relative speed calculating formula in the claims, and the second corrected target relative speed calculating formula is This corresponds to the correction target relative speed calculation formula in the curve. The vehicle control ECU 12 corresponds to a first storage unit and a second storage unit.

  Here, the corrected approach / separation evaluation index KdB_c (a), the first corrected target relative speed calculation formula, and the second corrected target relative speed calculation formula will be described.

  First, the corrected approaching / separating state evaluation index KdB_c (a) will be described. This corrected approaching / separating state evaluation index KdB_c (a) is based on Patent Document 1, the present inventors' “Study on the dangerous state evaluation accompanying front-and-rear direction approach (5th report)”, the automobile technology society academic lecture pre-print , No.38-07, pp.1-4, (2007), calculated based on the temporal change rate of the apparent area of the front object projected on the driver's retina. The basic formula is expressed by the following formula (8).

上記（８）式において、Vrは前車との相対速度、Dは前車との車間距離、Vpは前車の速度、aは定数である。この補正接近離間状態評価指標KdB_c(a)は、特許文献１に記載されているように、前車の速度を考慮して前車に対する接近離間状態を表す指標であり、（８）式から分かるように、前車に接近する相対速度が高くなるほど大きくなるとともに、各相対速度において前車との距離が短くなるほど増加勾配が急峻になる指標である。

In the above equation (8), Vr is a relative speed with respect to the preceding vehicle, D is an inter-vehicle distance from the preceding vehicle, Vp is a speed of the preceding vehicle, and a is a constant. The correction approach / separation state evaluation index KdB_c (a) is an index representing the approach / separation state with respect to the front vehicle in consideration of the speed of the front vehicle, as described in Patent Document 1, and can be obtained from equation (8). Thus, the index increases as the relative speed approaching the front vehicle increases, and increases as the distance from the front vehicle decreases at each relative speed.

However, in the present embodiment, when the vehicle is located outside the curve ahead of the vehicle (that is, outside the curve), the distance Ds to the entrance of the curve is set instead of the inter-vehicle distance D with the preceding vehicle. At the same time, instead of the speed Vp of the preceding vehicle, the target speed (hereinafter referred to as the target speed at the time of curve) Vr_Gy_offset ₀ when passing through the entrance of the curve is used. Further, instead of the relative speed Vr with respect to the preceding vehicle, a speed difference Vr_Gy _A between the curve target passing speed Vr_Gy_offset ₀ and the current speed Vs ₀ is used. That is, in this embodiment, when the vehicle is located outside the curve, the corrected approaching / separating state KdB_c (a) is calculated using equation (1).

なお、自車が自車前方に存在するカーブの内（つまり、カーブ内）に位置する場合に、前車との車間距離Dに代えて、自車先端から自車正面に位置する道路外側境界までの適正距離（以下、カーブ内適正道路境界距離D_ｃｎ）を用いるとともに、前車の速度Vpに代えて、カーブ内を走行する際の自車の目標速度（以下、カーブ内目標通過速度という）Vr_Gy_offset_ｎを用いる構成としてもよい。また、前車との相対速度Vrに代えて、このカーブ時目標通過速度Vr_Gy_offset_ｎと現在速度Vs₀との速度差Vr_Gy_Bを用いる。すなわち、本実施形態では、自車がカーブ内に位置する場合には、（９）式を用いて補正接近離間状態KdB_c(a)を算出する構成としてもよい。

In addition, when the vehicle is located within the curve existing in front of the vehicle (that is, within the curve), instead of the inter-vehicle distance D with the preceding vehicle, the road outer boundary located in front of the vehicle from the front end of the vehicle _Is used as the appropriate distance to the vehicle (hereinafter referred to as the appropriate road boundary distance D _cn within the curve), and instead of the speed Vp of the preceding vehicle, the target speed of the host vehicle when traveling in the curve (hereinafter referred to as the target passing speed within the curve). ) Vr_Gy_offset _n may be used. Further, instead of the relative speed Vr with respect to the preceding vehicle, a speed difference Vr_Gy _B between the curve target passing speed Vr_Gy_offset _n and the current speed Vs ₀ is used. That is, in this embodiment, when the own vehicle is located in the curve, the corrected approach / separation state KdB_c (a) may be calculated using the equation (9).

なお、カーブ内適正道路境界距離Dｃ_ｎは、道路の外側曲率半径Reおよびカーブ内適正旋回半径Re-Lから算出する。外側曲率半径Reとは、カーブ道路におけるカーブ部分の道路外側境界の曲率半径を意味している。

Incidentally, appropriate road boundary distance Dc _n in curve is calculated from the outer radius of curvature Re and curve within the appropriate turning radius Re-L of the road. The outer curvature radius Re means the curvature radius of the road outer boundary of the curved portion of the curved road.

The outer curvature radius Re is calculated as follows. FIG. 2 is a diagram for explaining the outer curvature radius Re and the appropriate turning radius Re-L. Outer radius of curvature Re is determined by detecting the front reference point P _O shown in FIG. 2, the left side reference point P _L, the position of the right reference point P _R by the radar 9. Here, the front reference point P _O is an intersection of the vehicle width direction center line L _O and the road outer boundary (line L in the case of a right curve road as shown in FIG. 2). Left reference point P _L is the intersection of the left offset line L _L and the road outside boundary offset by left offset distance W _L a vehicle width direction center line L _O to the vehicle width direction left. Right reference point P _R is the intersection of the right offset line L _R and the road outer boundary offset the vehicle width direction center line L _O to the vehicle width direction right by the right offset distance W _R.

A road accessory provided in the vicinity of the road outer boundary is approximately used as a road boundary. In the present embodiment, both the left offset distance W _L and the right offset distance W _R are set to 1 m. However, the left offset distance W _L and the right offset distance W _R are not limited to this, and may be longer than 1 m or shorter than 1 m. Further, the left offset distance W _L and the right offset distance W _R need not be the same length.

In the present embodiment, as shown in FIG. 2, a front reference point P _O, the left reference point P _L, the position of the right reference point P _R, the intersection of the width direction line LH and the left offset line L _L of the vehicle front end Detect as the origin coordinate.

Outer radius of curvature Re is calculated by substituting these front reference point P _O, the left reference point P _L, the coordinates of the right reference point P _R to (2). The outer radius of curvature Re corresponds to the actual outer radius of curvature in the claims.

なお、この（２）式は、道路外側境界を円弧として含む円の中心をO（a、b）とすると、その点O−右側基準点P_Rを斜辺とし、他の２辺のうちの１辺が幅方向線LHと平行な直角三角形の三平方の定理を示す（１０）式、点O−左側基準点P_Lを斜辺とし、他の２辺のうちの１辺が幅方向線LHと平行な直角三角形の三平方の定理を示す（１１）式、点O−正面基準点P_Oを斜辺とし、他の２辺のうちの１辺が幅方向線LHと平行な直角三角形の三平方の定理を示す（１２）式から導出できる。また、（２）式のDが自車から正面基準点までの距離を表しており、D_Ｌが自車から左側基準点までの距離を表しており、D_Ｒが自車から右側基準点までの距離を表している。

Incidentally, the equation (2), when the center of the circle including road outer boundary as an arc and O (a, b), of the hypotenuse that point O- right reference point P _R, the other two sides 1 Expression (10) showing a right triangle trigonometric theorem whose side is parallel to the width direction line LH, point O-left reference point P _L is a hypotenuse, and one of the other two sides is the width direction line LH. Formula (11) showing the theorem of the three squares of a parallel right triangle, point O-the front reference point _PO is the hypotenuse, and one of the other two sides is the three squares of the right triangle parallel to the width direction line LH It can be derived from the equation (12) showing the theorem. Further, to the right reference point (2) represents the distance from D is the vehicle of the type to the front reference point, D _L is represents the distance from the vehicle to the left side reference point, D _R is the vehicle Represents the distance.

適正旋回半径Re-Lは、（２）式から求めた外側曲率半径Reから、道路幅方向における道路境界から車両幅方向中心線L_Oまでの距離Lを引くことで求められる。なお、この距離Lの値は、前述したように、ナビゲーション装置１１に地図データとして記憶されている通行区分幅や道路幅員に基づいて決定してもよいし、レーダ９等を用いて先行車の横位置を決定して、先行車の横位置および先行車との横ずれ量から決定してもよい。

The appropriate turning radius Re-L is obtained by subtracting the distance L from the road boundary in the road width direction to the vehicle width direction center line L _O from the outer curvature radius Re obtained from the equation (2). As described above, the value of the distance L may be determined based on the traffic division width and road width stored as map data in the navigation device 11, or the radar 9 or the like may be used for the preceding vehicle. The lateral position may be determined and determined from the lateral position of the preceding vehicle and the amount of lateral deviation from the preceding vehicle.

Then, the appropriate road boundary distance Dc _n in curve calculated from the following equation (13). In the same way as the equation (12), this equation (13) has a point O-front reference point P _O as a hypotenuse, and one of the other two sides is a square triangle of a right triangle parallel to the width direction line LH. It is an expression showing the theorem. Therefore, appropriate road boundary distance within the curve Dc _n is meant the distance from the subject vehicle tip of when the vehicle is traveling on a circular track curve within the appropriate turning radius Re-L to the road outside the boundary located on the vehicle front To do.

補正接近離間評価指標KdB_c(a)の説明に戻って、前述の（８）式は、前車が存在する状況において自車のドライバが減速開始を行なうタイミングをよく示す指標であることが証明されている。そして、（１）式は、上述のように、（８）式において、Dに代えてカーブの入口までの距離Dsを用い、Vpに代えてカーブ時目標通過速度Vr_Gy_offset₀を用い、Vrに代えて、このカーブ時目標通過速度Vr_Gy_offset₀と現在速度Vs₀との速度差Vr_Gy_Aを用いている。従って、（１）式は、カーブの入口を通過するときの自車の速度をカーブ時目標通過速度Vr_Gy_offset₀としようとする場合に、ドライバが減速操作を開始する条件を示しているといえる。

Returning to the description of the corrected approach / separation evaluation index KdB_c (a), the above-described equation (8) is proved to be an index that well indicates the timing at which the driver of the own vehicle starts to decelerate in the situation where the front vehicle exists. ing. As described above, the expression (1) uses the distance Ds to the entrance of the curve instead of D in the expression (8), uses the target speed Vr_Gy_offset ₀ during the curve instead of Vp, and changes to Vr. Thus, the speed difference Vr_Gy _A between the target passing speed Vr_Gy_offset ₀ and the current speed Vs ₀ is used. Accordingly, it can be said that the expression (1) indicates a condition for the driver to start the deceleration operation when the vehicle speed when passing through the entrance of the curve is set to the curve target passing speed Vr_Gy_offset ₀ .

Note that (9), as described above, in (8), using the curve within the appropriate road boundary distance Dc _n in place of D, using the curve within the target passing speed Vr_Gy_offset _n instead of Vp, the Vr Instead, the speed difference Vr_Gy _B between the in-curve target passing speed Vr_Gy_offset _n and the current speed Vs ₀ is used. Accordingly, it can be said that the expression (2) indicates a condition for the driver to start the deceleration operation when the vehicle speed when traveling in the curve is set to the in-curve target passing speed Vr_Gy_offset _n .

  Next, the corrected target relative speed calculation formula will be described. First, the first corrected target relative speed calculation formula is obtained by correcting the formula (14) (target relative speed calculation formula). First, this target relative speed calculation formula will be described.

目標相対速度算出式は、以下の（１５）式（接近離間状態評価指標関係式）、および（１５）式を微分することで得られる（１６）式（接線式）とから求めることができる。

The target relative speed calculation formula can be obtained from the following formula (15) (approaching / separating state evaluation index relational formula) and formula (16) (tangential formula) obtained by differentiating formula (15).

これら（１４）式〜（１６）式において、Dは、自車進行方向の延長線上に位置し、自車の前方に存在するカーブの道路境界又はその付近に設けられた道路付帯物と自車との距離（つまり、前述の実道路境界距離）であり、Dc₀は、その道路境界又は道路付帯物とカーブ道路の入口（直線部終了位置）との距離（つまり、前述の適正道路境界距離）である。また、D₀は減速制御開始時のD、Vr_Gy_tはカーブの入口地点に対する自車の相対速度の目標値（目標相対速度）であり、KdBは接近離間状態評価指標、KdB₀は減速制御開始時のKdB、KdB_tはKdBの目標値（目標接近離間状態評価指標）である。

In these formulas (14) to (16), D is a road accessory and the vehicle that are located on the extension line in the traveling direction of the vehicle and that are provided at or near the road boundary of the curve in front of the vehicle. Dc ₀ is the distance between the road boundary or road accessory and the entrance of the curved road (straight line end position) (that is, the above-mentioned appropriate road boundary distance). ). D ₀ is D at the start of deceleration control, Vr_Gy_t is the target value (target relative speed) of the vehicle's relative speed with respect to the entrance point of the curve, KdB is an approach / separation state evaluation index, and KdB ₀ is at the start of deceleration control KdB and KdB_t are target values for KdB (target approach / separation state evaluation index).

Equation (15) is an approach / separation state evaluation index KdB indicating an approach / separation state with respect to the entrance of the curve existing in front of the host vehicle, the curve entrance arrival distance (D−Dc ₀ ), and the target relative speed (the entrance of the curve). (Target value of the relative speed of the vehicle with respect to the point). The higher the target relative speed Vr_Gy_t, the larger the approaching / separating state evaluation index KdB, and the curve target distance at the same target relative speed Vr_Gy_t This is an equation in which the increasing gradient of the approaching / separating state evaluation index KdB becomes steeper as (D−Dc ₀ ) becomes shorter. By substituting the target approach / separation state evaluation index KdB_t of equation (16) into KdB of equation (15), the target relative speed calculation equation represented by equation (14) is obtained.

Then, with respect to the equation (14) (target relative velocity calculation equation), the target relative velocity at the distance D = Dc ₀ is offset to the negative side by the curve target passage velocity Vr_Gy_offset ₀ , and from D = D ₀ to Dc ₀ The first corrected target relative speed calculation formula is a formula that changes at a speed obtained by multiplying the target relative speed Vr_Gy_t that can be calculated by the formula (14) by the ratio p1 shown in the formula (17).

すなわち、第１修正目標相対速度算出式は、（１８）式に示す式変形の後、（１８）式のVr_Gy₀項を右辺に移項することによって得られる（１９）式である。

That is, the first corrected target relative speed calculation formula is the formula (19) obtained by shifting the Vr_Gy ₀ term of the formula (18) to the right side after the formula transformation shown in the formula (18).

図４（ｃ）は、（１４）式から算出される目標相対速度Vr＿Gy_tの変化曲線と、（１９）式で示す第１修正目標相対速度算出式から算出される第１修正目標相対速度Vr＿Gy_t_after₀の変化曲線とを比較して示すグラフである。このグラフからも分かるように、第１修正目標相対速度Vr＿Gy_t_after₀は、距離Dc₀においてカーブ時目標通過速度Vr_Gy_offset₀となる。なお、前述のように、相対速度はカーブ入口地点に対するものであるので、この相対速度は自車速度Vs₀と正負が逆であるのみで絶対値は自車速度Vs₀に等しい。

FIG. 4C shows a change curve of the target relative speed Vr_Gy_t calculated from the expression (14) and the first corrected target relative speed Vr_Gy_t_after ₀ calculated from the first correction target relative speed calculation expression shown by the expression (19). It is a graph which compares and shows these change curves. As can be seen from this graph, the first corrected target relative speed Vr_Gy_t_after ₀ becomes the curve-time target passing speed Vr_Gy_offset ₀ at the distance Dc ₀ . As described above, since the relative speed is relative to the curve entrance point, this relative speed is merely opposite to the own vehicle speed Vs ₀ and the absolute value is equal to the own vehicle speed Vs ₀ .

Next, the second correction target relative speed calculation formula will be described. The second corrected target relative speed calculation formula is obtained by correcting the formula (19) (first corrected target relative speed calculation formula). Specifically, as shown in FIG. 5, the first corrected target relative speed Vr_Gy_t_after ₀ at the distance D = Dc _{0 and the} in-curve target passing speed Vr_Gy_offset _n and the curve on the positive side, as shown in FIG. The target entry speed Vr_Gy_offset is offset by the difference of _0, and the curve entrance arrival distance (D−Dc ₀ ) is offset by the difference of the appropriate road boundary distance Dc ₀ and the appropriate road boundary distance in the curve D _cn on the negative side. . Further, the ratio p2 shown in Expression (20) is set to a speed obtained by multiplying the first corrected target relative speed Vr_Gy_t_after ₀ that can be calculated by Expression (19), and the ratio q shown in Expression (21) is set to the curve entrance. An expression that is obtained by multiplying the reach distance (D−Dc ₀ ) is a second corrected target relative speed calculation expression.

すなわち、第２修正目標相対速度算出式は、（２２）式に示す式変形の後、（２２）式のVr_Gy₀項を右辺に移項することによって得られる（２３）式である。

That is, the second corrected target relative speed calculation formula is formula (23) obtained by shifting the Vr_Gy ₀ term of formula (22) to the right side after the formula transformation shown in formula (22).

次に、自車がカーブＲのカーブ道路に進入する状況を例として、車両制御ＥＣＵ１２の実行する減速制御処理について、図３に示すフローチャートを参照しながら説明する。この減速制御処理は、自車の進行方向前方の道路がカーブする場合に実行するものであり、路車間通信装置８を介してカーブ情報を受信することで実行を開始する。

Next, the deceleration control process executed by the vehicle control ECU 12 will be described with reference to the flowchart shown in FIG. This deceleration control process is executed when the road ahead in the traveling direction of the host vehicle is curved, and is started by receiving the curve information via the road-to-vehicle communication device 8.

First, in step S1, curve information including the curve R, the road surface friction coefficient μ in the curve, the coordinates of the entrance / exit point of the curve (latitude and longitude), the width of the curve, the number of lanes, the width of each lane, and the like are acquired. Further, vehicle information including the speed Vs _{0 of} the own vehicle, the coordinates (latitude and longitude) of the current position of the own vehicle is also acquired. Therefore, the vehicle control ECU 12 corresponds to a speed acquisition unit and a curvature radius acquisition unit.

  In step S2, the curve R on the curve road is obtained, and the process proceeds to step S3. As described above, the curve R may be configured to use data acquired by road-to-vehicle communication, for example, or may be configured to use the outer curvature radius Re obtained as described above. Therefore, the vehicle control ECU 12 corresponds to the road curvature radius calculation means in the claims. Here, in this flow, the case where the outer curvature radius Re is used as the curve R will be described as an example.

  In step S3, the actual distance from the front end of the vehicle to the outer boundary of the road located in front of the vehicle is determined based on the road boundary of the curve ahead of the vehicle detected by the radar 9 or the position of the road accessory provided in the vicinity thereof. (That is, the actual road boundary distance D) is calculated, and the process proceeds to step S4. Therefore, the vehicle control ECU 12 corresponds to the actual distance calculation means in the claims.

In step S4, the distance from the entrance point of the curve in front of the host vehicle to the road outer boundary (appropriate road boundary distance Dc ₀ ) is calculated by equation (7) as described above, and the process proceeds to step S5. In step S5, the distance from the correct road boundary distance Dc ₀ Metropolitan calculated in real road boundary distance D and S4 determined in step S3, to the entrance point of the curve of the front of the own vehicle from the vehicle, i.e., the curve entrance arrival distance Ds is calculated by equation (24), and the process proceeds to step S6. Therefore, vehicle control ECU12 is equivalent to the distance acquisition means of a claim.

ステップＳ６では、適正道路境界距離Dc₀と実道路境界距離Dとを比較することで前述のカーブ内外判定を行う。よって、車両制御ＥＣＵ１２が請求項のカーブ内外判定手段に相当する。具体的には、実道路境界距離Dが適正道路境界距離Dc₀よりも大きいか否かを判定する。そして、D＞Dc₀であった場合（ステップＳ６でＹＥＳ）には、自車がカーブ外に位置すると判定し、ステップＳ７に移る。また、D＞Dc₀でなかった場合（ステップＳ６でＮＯ）には、自車がカーブ内に位置すると判定し、ステップＳ１６に移る。

In step S6, it performs the curve outside judgment described above by comparing the appropriate road boundary distance Dc ₀ and the actual road boundary distance D. Therefore, the vehicle control ECU 12 corresponds to the curve inside / outside determination means in the claims. Specifically, it is determined whether the actual road boundary distance or D is larger than the appropriate road boundary distance Dc _0. If D> Dc ₀ (YES in step S6), it is determined that the vehicle is located outside the curve, and the process proceeds to step S7. If D> Dc ₀ is not satisfied (NO in step S6), it is determined that the vehicle is located within the curve, and the process proceeds to step S16.

In step S7, the curve information acquired in step S1 is referred to, and a target lateral G (Gy_t ₀ ) that is a target when passing through the entrance of the curve is calculated based on the road surface friction coefficient μ in the curve. Move. The target lateral G (Gy_t ₀ ) may be calculated based on Coulomb's law of friction so that the lateral force of the tire during steering operation of the host vehicle can be secured when traveling on a curve. The target lateral G (Gy_t ₀ ) corresponds to the first target lateral acceleration in the claims.

In step S8, the speed at which the vehicle can turn the curve at the target lateral G (Gy_t ₀ ) calculated in step S7 is set as the curve target passing speed Vr_Gy_offset ₀ using the equation (25). Control goes to step S9. Therefore, the vehicle control ECU 12 corresponds to a curve target speed setting means.

ステップＳ９では、ステップＳ８で設定したカーブ時目標通過速度Vr_Gy_offset₀と現在速度Vs₀との速度差Vr_Gy_Aを算出し、その速度差Vr_Gy_Aと、ステップＳ８で設定したカーブ時目標通過速度Vr_Gy_offset₀と、ステップＳ５で算出したカーブ入口到達距離Dsとを前述の（１）式に代入することで、補正接近離間状態評価指標KdB_c(a)の現在値（KdB_c(a)_p）を算出し、ステップＳ１０に移る。なお、（１）式の定数ａは予め実験に基づいて設定した値（たとえば０．３）を用いる。よって、車両制御ＥＣＵ１２が請求項の第１速度差算出手段および評価指標算出手段に相当する。

In step S9, the speed difference Vr_Gy _A between the curve target pass speed Vr_Gy_offset ₀ set in step S8 and the current speed Vs ₀ is calculated, and the speed difference Vr_Gy _A and the curve target pass speed Vr_Gy_offset ₀ set in step S8 are calculated. Then, the current value (KdB_c (a) _p) of the corrected approaching / separating state evaluation index KdB_c (a) is calculated by substituting the curve entrance arrival distance Ds calculated in step S5 into the above-described equation (1). Control goes to step S10. Note that the constant a in the equation (1) uses a value (for example, 0.3) set in advance based on experiments. Therefore, the vehicle control ECU 12 corresponds to the first speed difference calculating means and the evaluation index calculating means.

In step S10, in order to determine whether or not deceleration control of the host vehicle is to be started, whether or not the state shown in FIG. 4A has been reached, that is, the current value of the corrected approaching / separating state evaluation index calculated in step S9. It is determined whether or not KdB_c (a) _p exceeds a threshold KdB_c_t ₀ determined from the brake discriminant expressed by equation (26) and the curve entrance reach distance Ds calculated in step S5. If KdB_c (a) _p> KdB_c_t ₀ (YES in step S10), the process proceeds to step S11. If KdB_c (a) _p> KdB_c_t ₀ is not satisfied (NO in step S10), the process returns to step S1 to repeat the flow. Therefore, vehicle control ECU12 is equivalent to the threshold value determination means of a claim.

このブレーキ判別式は、先行車両に自車が接近する状況において、テストドライバに対して先行車両に衝突しないようブレーキのコントロールが可能なぎりぎりのタイミングでブレーキ操作を開始するように教示して実験したときに（８）式から算出できる補正接近離間状態評価指標KdB_c(a)と、ブレーキ操作開始時の先行車両までの距離との関係を示した近似式である（２７）式を修正した式である。すなわち、（２６）式で示すブレーキ判別式は、（２７）式のＤに、Ｄsを代入した式である。

This brake discriminant was tested and taught to start the brake operation at the last minute timing that allows the test driver to control the brake so that it does not collide with the preceding vehicle when the vehicle approaches the preceding vehicle. This is a modified formula of (27), which is an approximation that shows the relationship between the corrected approach / separation state evaluation index KdB_c (a) that can sometimes be calculated from (8) and the distance to the preceding vehicle at the start of the brake operation. is there. That is, the brake discriminant represented by the equation (26) is an equation in which Ds is substituted for D in the equation (27).

（２７）式は、先行車両に自車が接近する状況におけるドライバの減速行動の開始点をよく示していることが既に知られている。従って、（２６）式は、地点D-Dc₀、すなわち、カーブ道路の入口地点に接近する状況におけるドライバの減速行動の開始点をよく示す式であるといえる。

It is already known that the expression (27) well indicates the starting point of the driver's deceleration action in a situation where the host vehicle approaches the preceding vehicle. Therefore, the expression (26) can be said to be an expression that well indicates the point D-Dc ₀ , that is, the starting point of the driver's deceleration action in the situation where the vehicle approaches the entrance point of the curve road.

In step S11, the relative speed Vr_Gy ₀ (= −Vs ₀ ) obtained when an affirmative determination is made in step S10 and the curve entrance reach distance Ds (= D−Dc ₀ ) calculated in step S3 are substituted into equation (28). Thus, the initial value KdB ₀ of the approaching / separating state evaluation index is calculated, and the process proceeds to step S12. This equation (28) is a modification of equation (15).

ステップＳ１２では、（１９）式で示す第１修正目標相対速度算出式を用いて第１修正目標相対速度Vr_Gy_t_after₀を算出し、ステップＳ１３に移る。具体的には、まず、ステップＳ５と同様にして現在のカーブ入口到達距離Ds(=D-Dc₀）を算出する。そして、この現在のカーブ入口到達距離Ds(=D-Dc₀）と、ステップＳ１１で算出した接近離間状態評価指標の初期値KdB₀と、その初期値KdB₀の算出に用いたカーブ入口到達距離（D₀-Dc₀）と、ステップＳ１０で肯定判断したときの相対速度Vr_Gy₀とを（１９）式に代入することで第１修正目標相対速度Vr_Gy_t_after₀を算出する。よって、車両制御ＥＣＵ１２が請求項の第１目標相対速度算出手段に相当する。

In step S12, the first correction target relative speed Vr_Gy_t_after ₀ is calculated using the first correction target relative speed calculation expression shown by the equation (19), and the process proceeds to step S13. Specifically, first, the current curve entrance reach distance Ds (= D−Dc ₀ ) is calculated in the same manner as in step S5. The current curve entrance reach distance Ds (= D−Dc ₀ ), the initial value KdB _{0 of} the approaching / separating state evaluation index calculated in step S11, and the curve entrance reach distance used for calculating the initial value KdB ₀ The first corrected target relative speed Vr_Gy_t_after ₀ is calculated by substituting (D ₀ -Dc ₀ ) and the relative speed Vr_Gy ₀ at the time of affirmative determination in step S10 into the equation (19). Therefore, the vehicle control ECU 12 corresponds to the first target relative speed calculation means in the claims.

As described above, the expression (19) is an expression obtained by correcting the expression (14). The equation (14) is an equation that can be obtained from the equations (15) and (16), and the equation (16) is an approach and separation at the time of starting deceleration as shown in FIG. It is a straight line having a state evaluation index gradient (= dKdB / dD). Accordingly, the first corrected target relative speed Vr_Gy_t_after ₀ calculated in step S12 changes according to the gradient (= dKdB / dD) of the approach / separation state evaluation index at the time of starting deceleration. Equation (19) is a cubic function of the curve entrance reach distance Ds (= D−Dc ₀ ), and the first corrected target relative speed Vr_Gy_t_after ₀ changes in the shape shown in FIG.

In step S13, the current speed Vs ₀ of the host vehicle is acquired, the current relative speed Vr_Gy_p is obtained from the acquired current speed Vs ₀ , the current relative speed Vr_Gy_p and the first corrected target relative speed calculated in step S12. by substituting the Vr_Gy_t_after ₀ to (29), calculates the target relative deceleration GDp ₀ to be generated in the subject vehicle. Therefore, the vehicle control ECU 12 corresponds to the first target deceleration calculating means. Note that in (29), T is a divisor for converting a difference between the current relative speed Vr_Gy_p a first corrected target relative speed Vr_Gy_t_after ₀ to the target relative deceleration GDp _0, which appropriately is set It is.

ステップＳ１４では、ステップＳ１３で算出した目標相対減速度GDp₀をＶＳＣ_ＥＣＵ１へ出力し、ステップＳ１５に移る。ＶＳＣ_ＥＣＵ１は、車両制御ＥＣＵ１２から入力された目標相対減速度GDp₀が自車に発生するように、図示しないブレーキアクチュエータを用いた減速制御を実行する。よって、ＶＳＣ_ＥＣＵ１が請求項の第１制御手段に相当する。

In step S14, it outputs the target relative deceleration GDp ₀ calculated in step S13 to VSC_ECU1, proceeds to step S15. The VSC_ECU 1 executes deceleration control using a brake actuator (not shown) so that the target relative deceleration GDp ₀ input from the vehicle control ECU 12 is generated in the host vehicle. Therefore, VSC_ECU1 corresponds to the first control means in the claims.

In step S15, it is determined whether a deceleration control end condition is satisfied. As the deceleration control end condition, for example, that the own vehicle has stopped, that the current value KdB_c (a) _p of the corrected approaching / separating state evaluation index is below the threshold KdB_c_t ₀ determined from the brake discriminant, the vehicle speed Vs ₀ is It can be used that the target passing speed Vr_Gy_offset is ₀ at the time of curve. If the deceleration control end condition is satisfied (YES in step S15), the process returns to step S1 and the flow is repeated. If the deceleration control end condition is not satisfied (NO in step S15), the process returns to step S14 and the flow is repeated.

Shifting to the case where the vehicle is determined to be located within the curve by the curve inside / outside determination, in step S16, the appropriate distance from the vehicle tip to the road outer boundary located in front of the vehicle (that is, the appropriate road boundary distance within the curve). Dc _n ) is calculated by the equation (13) as described above, and the process proceeds to step S17. In the equation (13), the outside curvature radius (actual outside curvature radius of the curve) Re calculated based on the position of the road outside boundary detected by the radar 9 is used, and the inside of the curve of the own vehicle traveling on the curve is used. calculates an appropriate turning radius (Re-L in the formula), based on their actual outer radius of curvature and the curve proper turning radius, a configuration has been shown to calculate the curve within the appropriate road boundary distance Dc _n, necessarily this Not exclusively. For example, instead of the actual outer radius of curvature Re, a curve R acquired by road-to-vehicle communication may be used. In step S17, where the vehicle control ECU 12 corresponds to the in-curve turning radius calculating means and the in-curve appropriate distance calculating means in the claims, it is determined whether or not the vehicle has approached the road outer boundary beyond an appropriate range. , the actual road boundary distance D determined in step S3 it is determined whether below the curve within the appropriate road boundary distance Dc _n calculated in step S16. Then, the D <if it was Dc _n (YES in step S17), the flow proceeds to step S18. Moreover, if not a D <Dc _n (NO at step S17), and repeats the flow returns to step S16.

In step S18, the curve information acquired in step S1 is referred to, a target lateral G (Gy_t _n ) that is a target when traveling in the curve is calculated based on the road surface friction coefficient μ in the curve, and the process proceeds to step S19. . The target lateral G (Gy_t _n ) may be calculated based on the Coulomb friction law so that the lateral force of the tire during the steering operation of the host vehicle can be secured when traveling on a curve. This target lateral G (Gy_t _n ) corresponds to the second target lateral acceleration in the claims.

In step S19, the speed at which the vehicle can turn the curve at the target lateral G (Gy_t _n ) calculated in step S18 is set as an in-curve target passing speed Vr_Gy_offset _n using the equation (30). Move on to S20. Therefore, the vehicle control ECU 12 corresponds to the in-curve target speed setting means.

ステップＳ２０では、（２３）式で示す第２修正目標相対速度算出式を用いて第２修正目標相対速度Vr_Gy_t_after_ｎを算出し、ステップＳ２１に移る。具体的には、まず、ステップＳ１６と同様にして現在のカーブ内適正道路境界距離Dc_ｎを算出する。そして、この現在のカーブ内適正道路境界距離Dc_ｎと、ステップＳ１１で算出した接近離間状態評価指標の初期値KdB₀と、その初期値KdB₀の算出に用いたカーブ入口到達距離（D₀-Dc₀）と、ステップＳ１０で肯定判断したときの実道路境界距離D₀と、現時点での相対速度Vr_Gy₀とを（２３）式に代入することで第２修正目標相対速度Vr_Gy_t_after_ｎを算出する。よって、車両制御ＥＣＵ１２が請求項の第２目標相対速度算出手段に相当する。なお、車両制御ＥＣＵ１２は請求項の第２速度差算出手段にも相当する。また、第２修正目標相対速度Vr_Gy_t_after_ｎは、図５に示す形状で変化する。

In step S20, the second correction target relative speed Vr_Gy_t_after _n is calculated using the second correction target relative speed calculation formula shown by formula (23), and the process proceeds to step S21. Specifically, first, it calculates a proper road boundary distance Dc _n in the current curve in the same manner as in step S16. Then, the current and the appropriate road boundary distance Dc _n in curve, the initial value KdB ₀ of distance condition evaluation index calculated in step S11, the curve entrance arrival distance used for calculation of the initial value KdB ₀ (D ₀ - The second corrected target relative speed Vr_Gy_t_after _n is calculated by substituting Dc ₀ ), the actual road boundary distance D ₀ when affirmative determination is made in step S10, and the current relative speed Vr_Gy ₀ into the equation (23). . Therefore, the vehicle control ECU 12 corresponds to the second target relative speed calculation means in the claims. The vehicle control ECU 12 also corresponds to a second speed difference calculating means. Further, the second corrected target relative speed Vr_Gy_t_after _n changes in the shape shown in FIG.

In the present embodiment, the configuration in which the second corrected target relative speed Vr_Gy_t_after _n is calculated when it is determined that the host vehicle is located within the curve is shown, but the present invention is not necessarily limited thereto. For example, when it is determined that the host vehicle is located within a curve and the determination is made as to whether or not deceleration control of the host vehicle is to be started, the second corrected target relative speed Vr_Gy_t_after _n is calculated. Also good.

In this case, the speed difference Vr_Gy _B between the in-curve target passing speed Vr_Gy_offset _n set in step S19 and the current speed Vs ₀ is calculated, and the speed difference Vr_Gy _B and the in-curve target passing speed Vr_Gy_offset set in step S18 are calculated. _n and, an appropriate road boundary distance Dc _n calculated in curve in the step S15 is substituted into the aforementioned equation (9), the current value of the correction distance condition evaluation index KdB_c (a) (KdB_c (a ) _p) Is calculated. Note that the constant a in the equation (9) uses a value (for example, 0.3) set in advance based on experiments.

The current value KdB_c (a) _p of the corrected approaching / separating state evaluation index calculated as described above is used to determine whether or not to start deceleration control of the host vehicle. step S15 it is determined whether or exceeds the determined threshold KdB_c_t _n from the proper road boundary distance Dc _n in curve calculated. Then, when KdB_c (a) _p> KdB_c_t _n , the second corrected target relative speed Vr_Gy_t_after _n may be calculated using the second corrected target relative speed calculation formula shown in Expression (23). If KdB_c (a) _p> KdB_c_t _n is not satisfied, the process may return to step S16 to repeat the flow.

なお、（３１）式で示すブレーキ判別式は、前述の（２７）式を修正した式である。すなわち、（３１）式で示すブレーキ判別式は、（２７）式のＤに、Dc_ｎを代入した式である。従って、（３１）式は、カーブ内においてカーブの道路外側境界に接近する状況におけるドライバの減速行動の開始点をよく示す式であるといえる。

Note that the brake discriminant represented by equation (31) is a modified equation of equation (27) described above. That is, the brake discriminant indicated by equation (31) is (27) to D of formula is an equation obtained by substituting Dc _n. Therefore, the equation (31) can be said to be an equation that well indicates the starting point of the driver's deceleration action in a situation in which the vehicle approaches the outer road boundary of the curve.

According to this, even if it is determined that the host vehicle is located within the curve, it is set before entering the curve until an affirmative determination is made on whether to start deceleration control of the host vehicle. The traveling at the first corrected target relative speed Vr_Gy_t_after ₀ is continued. Therefore, when the curve R of the target curve is constant, it does not deviate outside the curve even after entering the curve without newly calculating the second corrected target relative speed Vr_Gy_t_after _n. The car can run smoothly on the curve.

In step S21, acquires the current speed Vs ₀ of the subject vehicle from the current speed Vs ₀ was the acquisition, obtains a current relative speed Vr_Gy_p, second corrected target relative speed calculated in this current relative speed Vr_Gy_p and step S20 and Vr_Gy_t_after _n (32) by substituting the equation to calculate the target relative deceleration GDp _n to be generated in the subject vehicle. Therefore, the vehicle control ECU 12 corresponds to the second target deceleration calculating means. Note that in equation (32), T is a divisor for converting a difference between the current relative speed Vr_Gy_p and second corrected target relative speed Vr_Gy_t_after _n to the target relative deceleration GDp _n, which suitably is set It is.

そして、ステップＳ２２では、ステップＳ２１で算出した目標相対減速度GDp_ｎをＶＳＣ_ＥＣＵ１へ出力し、ステップＳ２３に移る。ＶＳＣ_ＥＣＵ１は、車両制御ＥＣＵ１２から入力された目標相対減速度GDp_ｎが自車に発生するように、図示しないブレーキアクチュエータを用いた減速制御を実行する。よって、ＶＳＣ_ＥＣＵ１が請求項の第２制御手段に相当する。

In step S22, the target relative deceleration GDpn calculated in step S21 is output to VSC_ECU _1, and the process proceeds to step S23. VSC_ECU1, the target relative deceleration GDp _n input from the vehicle control ECU12 is to occur on the vehicle, to execute a deceleration control using a brake actuator (not shown). Therefore, VSC_ECU1 corresponds to the second control means in the claims.

In a succeeding step S23, it is determined whether or not a deceleration control end condition is satisfied. As the speed reduction control termination condition, for example, can be used as the vehicle is and it has stopped, the current value KdB_c_p correction distance condition evaluation index is or falls below a threshold KdB_c_t _n determined from the brake discriminant. If the deceleration control end condition is satisfied (YES in step S23), the flow ends. If the deceleration control end condition is not satisfied (NO in step S23), the process returns to step S22 and the flow is repeated.

In the driving support system 100 operating in this way, the current value KdB_c (a) _p of the corrected approaching / separating state evaluation index considering the curve target passing speed Vr_Gy_offset _{0 is used} to determine the deceleration control start timing before the curve. The time when the current value KdB_c (a) _p exceeds the threshold value KdB_c_t ₀ determined from the brake discriminant expressed by equation (26) is set as the deceleration control start time. Accordingly, the deceleration control can be started at a timing that matches the driver's feeling when attempting to pass the curve at the curve target passing speed Vr_Gy_offset ₀ .

In the deceleration control, the deceleration control is performed based on the first corrected target relative speed Vr_Gy_t_after ₀ calculated using the first corrected target relative speed calculation formula shown by the equation (19). The first correction target relative speed Vr_Gy_t_after ₀ calculated by the first correction target relative speed calculation formula changes smoothly as shown in FIG. The first corrected target relative speed calculation formula is based on the approaching / separating state evaluation index KdB, and the approaching / separating state evaluation index KdB has already been recognized by academic societies and the like as an index well indicating the driver's sense of danger. ing. Therefore, by performing deceleration control based on the first corrected target relative speed Vr_Gy_t_after ₀ calculated using the first corrected target relative speed calculation formula, smooth control suitable for the driver's sense of danger can be performed.

Moreover, as shown in FIG. 4 (c), since the curve-time target passing speed Vr_Gy_offset ₀ is obtained at the point of the distance Dc ₀ , that is, the entrance point of the curve, when the straight part of the curved road ends and enters the curved part However, there is no speed inflection point and it is possible to run smoothly.

Further, when the curve R of the target curve is constant, as shown in FIG. 6, the vehicle does not deviate outside the curve while maintaining the state of D = D _c0 even after entering the curve. The car can run smoothly on the curve. FIG. 6 is a diagram for explaining an example when the host vehicle enters a curve with a constant curvature at a curve target passing speed Vr_Gy_offset ₀ .

On the other hand, in the driving support system 100, in the deceleration control within the curve, the deceleration control is performed based on the second corrected target relative speed Vr_Gy_t_after _n calculated using the second corrected target relative speed calculation formula (23). It is carried out. The second correction target relative speed Vr_Gy_t_after _n calculated by the second correction target relative speed calculation formula changes smoothly as shown in FIG. Similarly to the first corrected target relative speed calculation formula, the second corrected target relative speed calculation formula is an expression based on the approaching / separating state evaluation index KdB, and the approaching / separating state evaluation index KdB well indicates the driver's sense of danger. It is already recognized by academic societies as an indicator. Therefore, by performing deceleration control based on the second corrected target relative speed Vr_Gy_t_after _n calculated using the second corrected target relative speed calculation formula, smooth control suitable for the driver's sense of danger can be performed.

For example, as shown in FIG. 7, even when the curve R is for changing to a larger curve R in the middle curve (change from Ra ₀ in FIG. 7 to Ra _n), the road outside located on the vehicle front with the boundary subjected to the distance condition evaluation index, the target relative speed and a curve within the target passing speed Vr_Gy_offset _n when the distance D is the curve within the appropriate road boundary distance Dc _n to the road outer boundary from subject vehicle tip Thus, deceleration control is performed. Thus, greater changes in the curve R, even when the actual road boundary distance D has become smaller than the appropriate road boundary distance Dc _n in curve, the actual road boundary distance D curve within the appropriate road boundary distance in the middle curve extent that becomes smaller than Dc _n, deceleration control so that the target relative speed is also reduced is performed. Therefore, even when the curve R becomes large in the middle of the curve, it is not necessary to deviate to the outside of the curve, and smooth deceleration control suitable for the driver's danger can be performed. FIG. 7 is a schematic diagram for explaining the deceleration control when the curve R changes from small to large during the curve.

Further, as shown in FIG. 8, the road surface before the entrance of the target curve is low μ due to freezing or the like, and the first corrected target relative speed calculated using the first corrected target relative speed calculation formula is used. Even if the deceleration control is performed based on the road outer boundary located in front of the vehicle even if the vehicle cannot decelerate to the curve target passing speed Vr_Gy_offset ₀ by the entrance of the curve, distance D from subject vehicle tip to the road outside the boundary is possible to perform deceleration control such that the target relative speed when a curve within the appropriate road boundary distance Dc _n is a curve within the target passing speed Vr_Gy_offset _n. Therefore, not be decelerated to the entrance of the curve to the curve at the target passing speed Vr_Gy_offset _0, even when entering into a curve in an understeer condition, the actual road boundary distance D by an amount becomes smaller than the appropriate road boundary distance Dc _n The deceleration control is performed so that the target relative speed is also reduced. Therefore, even if the vehicle enters the curve with the target passing speed Vr_Gy_offset of ₀ or more and enters an understeer state, it does not need to deviate outside the curve and performs smooth deceleration control that matches the driver's danger. Is possible. FIG. 8 is a schematic diagram for explaining the deceleration control when the vehicle cannot be decelerated to the curve target passing speed Vr_Gy_offset ₀ by the low μ road before the curve entrance until the curve entrance.

  Further, the vehicle control ECU 12 may determine whether or not the steering angle is appropriate in a predetermined cycle during traveling of the host vehicle, and automatically controls the steering angle when the steering angle is not appropriate. Therefore, the vehicle control ECU 12 corresponds to the steering angle appropriateness determining means in the claims. In the following, the determination of the appropriateness of the steering angle and the automatic control of the steering angle will be described.

First, when the above-mentioned curve outside judgment in the vehicle is determined to be located within the curve, the determination of the appropriateness of the steering angle calculates the appropriate road boundary distance Dc _n in curve as described above, the curve It carried out by comparing the inner appropriate road boundary distance Dc _n and the actual road boundary distance D.

Figure 9 is a diagram showing a curve within the appropriate road boundary distance Dc _n of the vehicle passing through the curve road. The vehicle shown in FIG. 9 is in a state where the vehicle is traveling at an appropriate turning radius Re-L in the curve. Thus, when the vehicle is traveling at the appropriate turning radius Re-L in the curve, the actual road boundary is the distance D is equal to the curve within the appropriate road boundary distance Dc _n. On the other hand, as shown in FIG. 10, the vehicle deviates from the turning trajectory having the appropriate turning radius Re-L in the curve, that is, the vehicle collides with the outer boundary of the road or protrudes outward from the road. the put away state, the actual road boundary distance D is shorter than the appropriate road boundary distance Dc _n in curve.

Thus, by comparing the appropriate road boundary distance Dc _n and the actual road boundary distance D within the curve, when more of the actual road boundary distance D is shorter than the appropriate road boundary distance Dc _n in curve, incorrect steering wheel angle is It is determined that

In addition, when the vehicle inside / outside determination described above determines that the vehicle is located outside the curve, the appropriate road boundary distance Dc ₀ and the actual road boundary distance D calculated as described above are used to determine whether the steering angle is appropriate. comparing the door, if more of the actual road boundary distance D is shorter than the appropriate road boundary distance Dc _0, it determines a steering wheel angle is inappropriate.

  Next, an example of the steering control related process executed by the vehicle control ECU 12 will be described with reference to the flowchart of FIG. The steering control related process shown in FIG. 11 is repeatedly executed at a predetermined repetition cycle. In addition, here, a description will be given by taking as an example a case where it is determined in the above-described curve inside / outside determination that the vehicle is located within the curve.

First, in step S101, by using the radar 9, it detects the front reference point P _O, the left reference point P _L, the right side reference point P _R, the flow proceeds to step S102. In step S31, these three reference points cannot always be detected. On the other hand, the radar 9 may detect other portions of the road outer boundary. In that case, the reference point is determined using the position of the other part of the road outer boundary that can be detected. Therefore, the vehicle control ECU 12 corresponds to the reference point detection means in the claims.

Therefore, in step S102, it is determined front reference point P _O, the left reference point P _L, whether it has detected all right reference point P _R. If all three reference points have been detected (YES in step S102), the process proceeds to step S104. If at least one of the three reference points cannot be detected (NO in step S102), the process proceeds to step S33.

In step S103, an insufficient reference point is determined so that there are three reference points together with the reference point detected in step S101, and the process proceeds to step S104. For example, if there is no road boundary on the right side offset line L _R can not detect the right reference point P _R. In this case, the intersection point P _{L_2} between the intermediate line and the road outer boundary bisecting between the vehicle width direction center line P _O and left offset line L _L, is determined as a reference point in place of the right reference point P _R. Although the position of the intersection point P _{L_2} are those detected by the radar 9, in a simplified manner, two reference points P _O, by interpolation using the P _L, the two reference points P _O, among the P _L A point may be used as a reference point. As described above, when only two reference points can be detected, a detection point or an interpolation point between the two reference points is set as a third reference point. Further, even when two or more reference points cannot be detected, a reference point may be created by interpolation from points on the road outer boundary that can be actually detected.

  In step S104, it is determined whether or not collision avoidance is necessary. The state where collision avoidance is necessary is a case where one of the reference points detected in step S101 is a point on the inner road boundary. When one of the reference points detected in step S101 is a point on the inner road boundary, if the steering angle is controlled so as to follow the curve road shape ahead, it will collide with the road inner boundary, or It will stick out the road inner boundary. Therefore, steering control for avoiding a collision is necessary.

Step S104, specifically, the distance D _L from the vehicle to the left side reference point P _L, the distance D from the vehicle to the front reference point P _O, the distance D _R from the vehicle to the right reference point P _R relationship, D _L, D, or a related increase in the order of D _R, or, D _L, D, when a relationship that decreases in the order of D _R, all on the road outer boundary three reference points Since this is considered to be a point, collision avoidance is not necessary (NO in step S104), and the process proceeds to step S105. On the other hand, if the relationship between D _L , D, and D _R is other than the above, it is determined that collision avoidance is necessary (YES in step S104), and the process proceeds to step S111.

In step S105, it calculates a distance D _R of the distance D _L from the vehicle to the left side reference point P _L, from the distance D, the vehicle from the vehicle to the front reference point P _O to the right reference point P _R, step S106 Move on. The distance D corresponds to the actual road boundary distance described above.

In step S106, the outer radius of curvature Re is calculated by substituting these three distances D _L , D, D _R , the left offset distance W _L , and the right offset distance W _R into the above-described equation (2). The process moves to S107. In step S107, the appropriate turning radius Re-L in the curve is calculated by subtracting the distance L from the vehicle width direction center line in the vehicle width direction to the road boundary from the outer curvature radius Re calculated in step S106, and step S108. Move on.

In step S108, by substituting the outer radius of curvature Re calculated in step S106, the appropriate turning radius Re-L calculated in curves at step S107 in the aforementioned (13), and calculates the curve within the appropriate road boundary distance Dc _n The process proceeds to step S109.

In step S109, the comparing curves in the appropriate road boundary distance Dc _n calculated in step S108, and the actual road boundary distance D calculated in step S105. If the actual road boundary distance D is _{equal to} or greater than the appropriate road boundary distance Dcn within the curve (NO in step S109), the flow is terminated without controlling the steering angle. Further, if the actual road boundary distance D is shorter than the appropriate road boundary distance Dc _n in curve (YES in step S109), the process proceeds to step S110.

  In step S110, steering angle control is executed. Here, the steering angle control will be described in detail with reference to FIG. FIG. 12 is a flowchart showing an example of the flow of steering angle control.

First, in step 201, the estimated outer curvature radius Ra is calculated from the following equation (6), and the process proceeds to step S202. In (6), Dc _n is the distance of the proper road boundary distance within the curve, L represents a road boundary in the road width direction to the vehicle width direction center line L _O. The estimated outer curvature radius Ra is an outer curvature radius for steering angle control. On the other hand, the aforementioned outer radius of curvature Re is an outer radius of curvature for determining whether or not the steering angle is appropriate. However, the aforementioned outer radius of curvature Re may be used to control the steering angle. Further, the expression (6) is an expression that can be derived from the theorem of the square of a right triangle.

ステップＳ２０２では、ステップＳ２０１で算出した推定外側曲率半径Ra等を下記（４）式に代入することで、タイヤ切れ角θを算出し、ステップＳ２０３に移る。なお、（４）式において、WBは車両ホイールベースである。

In step S202, the tire turning angle θ is calculated by substituting the estimated outer curvature radius Ra and the like calculated in step S201 into the following equation (4), and the process proceeds to step S203. In the formula (4), WB is a vehicle wheel base.

ステップＳ２０３では、ステップＳ２０２で算出したタイヤ切れ角θを下記（５）式に代入することで得られる値を、目標ステアリング切り角Θに設定し、ステップＳ２０４に移る。よって、車両制御ＥＣＵ１２が請求項の目標角設定手段に相当する。なお、（５）式において、Nはステアリング切り角Θとタイヤ切れ角θとの比率（定数）である。

In step S203, a value obtained by substituting the tire turning angle θ calculated in step S202 into the following equation (5) is set as the target steering turning angle Θ, and the process proceeds to step S204. Therefore, the vehicle control ECU 12 corresponds to the target angle setting means in the claims. In the equation (5), N is a ratio (constant) between the steering angle θ and the tire angle θ.

ステップＳ２０４では、ステアリング切り角を実際に変化させる。具体的には、ステップＳ２０３で設定した目標ステアリング切り角ΘをＥＰＳ_ＥＣＵ６へ送信する。ＥＰＳ_ＥＣＵ６は、舵角センサ２によってステアリング切り角を検出しつつＥＰＳアクチュエータ７を制御して、ステアリング切り角を所定の変化速度で目標ステアリング切り角Θに近づく方向に変化させる。よって、ＥＰＳ_ＥＣＵ６が請求項のステアリング切り角制御手段に相当する。そして、ステップＳ１１０のステアリング切り角制御を実行した後は、フローを終了する。

In step S204, the steering angle is actually changed. Specifically, the target steering angle Θ set in step S203 is transmitted to the EPS_ECU 6. The EPS_ECU 6 controls the EPS actuator 7 while detecting the steering angle by the rudder angle sensor 2, and changes the steering angle in a direction approaching the target steering angle Θ at a predetermined change speed. Therefore, the EPS_ECU 6 corresponds to the steering angle control means in the claims. Then, after executing the steering angle control in step S110, the flow ends.

Returning to FIG. 11, in step S 111, 3 one distance D _L, and set D, the shortest distance curve within the appropriate road boundary distance Dc _n of D _R, the flow proceeds to step S112. In step S112, the steering angle control is executed in the same manner as described above, the process returns to step S101, and the flow is repeated. By executing the steering angle control in this step S112, the direction of the own vehicle gradually changes along the traveling road, and a collision with the road inner boundary is avoided. If all three reference points are points on the road outer boundary, it is determined that collision avoidance is not necessary in step S104, and the process proceeds to step S105 and subsequent steps.

  In addition, here, an example of the steering control related processing when it is determined that the own vehicle is located within the curve by the inside / outside determination of the curve is given, but the steering control when it is determined that the own vehicle is located outside the curve by the inside / outside curve determination The related processing may be performed in the same manner.

More specifically, in step S109, instead of the curve within the appropriate road boundary distance Dc _n, it compares the appropriate road boundary distance Dc ₀ and the actual road boundary distance D, the actual road boundary distance D is proper road boundary distance Dc ₀ or more If it is, while the flow is completed without performing the control of the steering wheel angle, may be configured to actual road boundary distance D executes the steering wheel angle control is shorter than the appropriate road boundary distance Dc ₀ . The appropriate road boundary distance Dc ₀ may be calculated as described above.

In this case, in the steering angle control, the estimated outer curvature radius Ra may be calculated from the following equation (3). In equation (3), Dc ₀ is the appropriate road boundary distance, and L is the distance from the road boundary in the road width direction to the center line L _{O in the} vehicle width direction.

以上の構成によれば、レーダ９によって検出される道路境界等の位置に基づいて、外側曲率半径Re、適正旋回半径Re-L、およびカーブ内適正道路境界距離Dc_nや適正道路境界距離Dc₀を順に算出している。すなわち、これら外側曲率半径Re、適正旋回半径Re-L、カーブ内適正道路境界距離Dc_n、適正道路境界距離Dc₀をいずれもレーダ９によって検出される道路境界等の位置から算出している。また、実道路境界距離Dもレーダ９によって検出される道路境界等の位置から算出している。そのため、装置構成を簡素化することができ、且つ、処理も比較的簡易となる。

According to the above configuration, based on the position of such road boundary detected by the radar 9, the outer radius of curvature Re, appropriate turning radius Re-L, and the curve within the appropriate road boundary distance Dc _n and proper road boundary distance Dc ₀ Are calculated in order. That is, these outer radius of curvature Re, is calculated from the appropriate turning radius Re-L, curve within the appropriate road boundary distance Dc _n, the position of the road boundary or the like to be detected by appropriate road boundary distance Dc ₀ Both radar 9. The actual road boundary distance D is also calculated from the position of the road boundary detected by the radar 9. Therefore, the apparatus configuration can be simplified, and the process is relatively simple.

  Further, since the position of the road boundary or the like actually detected by the radar 9 is used as information for determining whether or not the steering angle is appropriate, the road shape is determined based on the map information, and based on the determined road shape. Thus, the suitability of the steering angle can be determined with higher accuracy than the suitability of the steering angle.

  The present invention is not limited to the above-described embodiments, and various modifications can be made within the scope of the claims, and the technical means disclosed in different embodiments can be appropriately combined. Such embodiments are also included in the technical scope of the present invention.

1 VSC_ECU (first control means, second control means), 2 steering angle sensor, 3 G sensor, 4 yaw rate sensor, 5 ENG_ECU, 6 EPS_ECU (steering angle control means), 7 EPS actuator, 8 road-to-vehicle communication device, 9 Radar (position detection sensor), 10 operation SW, 11 navigation device, 12 vehicle control ECU (turning radius calculation means, appropriate distance calculation means, first storage means, second storage means, speed acquisition means, curvature radius acquisition means, Road curvature radius calculation means, distance acquisition means, actual distance calculation means, curve inside / outside determination means, curve target speed setting means, first speed difference calculation means, evaluation index calculation means, threshold value determination means, first target relative speed calculation means , First target deceleration calculation means, in-curve turning radius calculation means, in-curve appropriate distance calculation means, in-curve target speed setting Means, second speed difference calculating means, second target relative speed calculating means, second target deceleration calculating means, steering turning angle appropriateness determining means, reference point detecting means, target angle setting means), 100 driving support system (for vehicle) Behavior control device)

Claims (5)

Distance acquisition means for sequentially acquiring a curve entrance arrival distance, which is a distance until the own vehicle reaches the entrance of the curve existing in front of the vehicle;
Speed acquisition means for acquiring the speed of the vehicle;
A radius of curvature acquisition means for acquiring a radius of curvature of the curve;
A curve target that is a target speed when the host vehicle passes the entrance of the curve from a radius of curvature of the curve and a first target lateral acceleration that is targeted when the host vehicle passes the entrance of the curve Curving target speed setting means for setting the passing speed;
First speed difference calculating means for calculating a speed difference of the host vehicle speed with respect to the curve target passing speed;
An index calculated based on a temporal change rate of an apparent area of a forward object projected on a retina of a driver, and the approaching and separating state of the own vehicle with respect to an entrance of a curve existing in front of the own vehicle As an index representing the curve target passing speed, the larger the speed difference of the vehicle speed with respect to the curve target passing speed, the shorter the curve entrance arrival distance at the same speed difference. An evaluation index calculation means for sequentially calculating a correction approaching / separating state evaluation index in which the increasing gradient becomes steeper,
Threshold judging means for judging whether or not the corrected approaching / separating state evaluation index calculated by the evaluation index calculating means exceeds a threshold determined from a threshold calculation formula of the corrected approaching / separating state evaluation index;
An approach and separation state evaluation index representing an approach and separation state with respect to an entrance of a curve existing in front of the host vehicle, an expression indicating a relationship between the curve entrance arrival distance and a relative speed with respect to the entrance of the curve, wherein the relative As the speed increases, the approaching / separating state evaluation index becomes larger, and at the same relative speed, the increasing distance of the approaching / separating state evaluation index becomes steeper as the curve entrance distance becomes shorter. An expression,
An equation indicating a tangent of a curve represented by the approaching / separating state evaluation index relational expression, which is obtained by differentiating the approaching / separating state evaluation index relational expression by the curve entrance reach distance, The equation showing the relationship with the curve entrance reach distance is a tangent equation,
Obtained from these approach and separation state evaluation index relational expression and tangent formula, when the target relative speed calculation formula in which the target relative speed is determined based on the curve entrance reach distance,
The target relative speed calculation formula is such that the first corrected target relative speed is calculated by the target relative speed calculation formula so that the target relative speed at the entrance of the curve becomes the curve target passing speed. Corrected target relative speed calculation formula corrected to be a speed obtained by multiplying the speed of the own vehicle at the start of control by the ratio of the difference between the speed of the own vehicle at the start of control and the target passing speed at the time of the curve. First storage means for storing
When it is determined that the threshold value determination means exceeds the threshold value, the first correction target is calculated from the correction target relative speed calculation formula stored in the first storage means and the curve entrance arrival distance actually acquired by the distance acquisition means. First target relative speed calculating means for calculating relative speed;
First target deceleration calculation means for calculating a target deceleration from the first corrected target relative speed calculated by the first target relative speed calculation means and the actual speed of the host vehicle acquired by the speed acquisition means;
First control means for executing deceleration control of the vehicle based on the target deceleration calculated by the first target deceleration calculating means;
A position detection sensor for detecting a position of a road accessory provided at or near a road boundary of a curve existing in front of the host vehicle;
Based on the curvature radius of the curve, an in-curve turning radius calculation means for calculating an appropriate turning radius in the curve of the host vehicle traveling on the curve;
Based on the curvature radius of the curve and the appropriate turning radius within the curve, an appropriate distance calculation means within the curve that calculates an appropriate distance from the vehicle tip to the road outer boundary located in front of the vehicle as an appropriate road boundary distance within the curve;
The in-curve target passing speed, which is the target speed when the vehicle travels within the curve, from the radius of curvature of the curve and the second target lateral acceleration that is targeted when the vehicle travels within the curve. In-curve target speed setting means for setting
Second speed difference calculating means for calculating a speed difference of the host vehicle speed with respect to the in-curve target passing speed;
The first corrected target relative speed is calculated from the corrected target relative speed calculation formula so that the second corrected target relative speed is calculated by the corrected target relative speed calculation formula so that the target relative speed becomes the in-curve target passing speed. And the speed obtained by multiplying the difference between the speed of the vehicle at the start of the control and the target passing speed at the time of the curve by the ratio of the speed of the own vehicle at the start of the control and the target passing speed within the curve. The curve entrance arrival distance in the corrected target relative speed calculation formula is the curve entrance arrival distance with respect to the difference between the actual road boundary distance at the start of the control and the appropriate road boundary distance. A second memory for storing an in-curve corrected target relative speed calculation formula that is corrected to be a distance obtained by multiplying the ratio of the difference between the actual road boundary distance at the start of control and the appropriate road boundary distance in the curve. And the stage,
Second target relative for calculating a second corrected target relative speed from the in-curve corrected target relative speed calculation formula stored in the second storage means and the in-curve appropriate road boundary distance calculated by the in-curve appropriate distance calculating means. A second target deceleration for calculating a target deceleration from the speed calculation means, the second corrected target relative speed calculated by the second target relative speed calculation means, and the actual speed of the host vehicle acquired by the speed acquisition means. Speed calculation means;
Second control means for executing deceleration control of the host vehicle based on the target deceleration calculated by the second target deceleration calculating means;
Based on the position of the road boundary or road accessory detected by the position detection sensor, the actual distance calculation means calculates the actual distance from the front end of the vehicle to the road outer boundary located in front of the vehicle as the actual road boundary distance. When,
A turning radius calculating means for calculating an appropriate turning radius of the own vehicle when traveling on the curve based on the curvature radius of the curve;
Based on the curvature radius and the appropriate turning radius of those curves, an appropriate distance calculation means for calculating an appropriate distance from the vehicle tip to the road outer boundary located in front of the vehicle as an appropriate road boundary distance;
Whether the vehicle is located outside or within the curve based on the magnitude relationship between the appropriate road boundary distance calculated by the appropriate distance calculation means and the actual road boundary distance calculated by the actual distance calculation means And a curve inside / outside judging means for judging
When the vehicle inside / outside determination means determines that the vehicle is located outside the curve, the vehicle control is performed by the first control means while the vehicle inside / outside curve is controlled by the curve inside / outside determination means. When it is determined that the vehicle is located, the vehicle behavior control device is configured to execute deceleration control of the host vehicle by the second control means. In claim 1,
The vehicle behavior control apparatus characterized in that the evaluation index calculation means calculates a corrected approaching / separating state evaluation index from equation (1).

KdB_c (a): Corrected approach / separation state evaluation index
Vr_Gy _A : Speed difference calculated by the first speed difference calculation means
a: Constant
Vr_Gy_offset ₀ : Curve target speed set by the curve target speed setting means
Ds: Curve entrance arrival distance acquired by the distance acquisition means In claim 1 or 2,
Road curvature radius calculating means for calculating an actual outer radius of curvature of the curve based on the position of the road boundary or road accessory detected by the position detection sensor;
A front reference point that is an intersection of the road outer boundary and the vehicle width direction center line of the own vehicle, a left offset line that is offset from the vehicle width direction center line to the vehicle width direction left side by a left offset distance, and the road outer boundary. Using the position detection sensor, a left reference point that is an intersection point, and a right reference point that is an intersection point between the road outer boundary and a right offset line obtained by offsetting a vehicle width direction center line to the right in the vehicle width direction by a right offset distance It further comprises a reference point detection means for detecting,
The vehicle curvature control device, wherein the road curvature radius calculation means calculates an actual outer curvature radius as a curvature radius of the curve from the equation (2).

Re: Actual outer radius of curvature
W _L : Left offset distance
W _R : Right offset distance
D: Distance from own vehicle to front reference point
D _L : Distance from own vehicle to left reference point
D _R: distance from the vehicle to the right reference point In any one of Claims 1-3,
When the vehicle inside / outside determining means determines that the vehicle is located outside the curve, the appropriate road boundary distance calculated by the appropriate distance calculating means is compared with the actual road boundary distance calculated by the actual distance calculating means. On the basis of the steering angle of the host vehicle based on the curve, and when the vehicle inside / outside determining unit determines that the vehicle is located within the curve, A vehicle including steering angle appropriateness determining means for determining appropriateness of the steering angle of the host vehicle based on a comparison between an appropriate road boundary distance and an actual road boundary distance calculated by the actual distance calculating means. Behavior control device. In claim 4,
The appropriate distance calculated by the appropriate distance calculation means when the vehicle inside / outside determination means determines that the vehicle is located outside the curve and the steering angle determination means determines that the steering angle is not appropriate. Calculate the estimated outer curvature radius from the road boundary distance and equation (3), calculate the tire turning angle from the estimated outer curvature radius and equation (4), and turn the steering from the tire turning angle and equation (5). An angle is calculated, and the steering angle is set as a target steering angle. On the other hand, when the vehicle inside / outside determination unit determines that the vehicle is located within the curve, the steering angle is determined by the steering angle appropriateness determination unit. Is determined to be inappropriate, the appropriate road boundary distance in the curve calculated by the appropriate distance calculation means in the curve and the equation (6) The estimated outside curvature radius is calculated, the tire turning angle is calculated from the estimated outside curvature radius and Equation (4), the steering angle is calculated from the tire turning angle and Equation (5), and the steering angle is calculated. Target angle setting means for setting as a target steering angle,
A vehicle behavior control device further comprising: a steering angle control unit that controls a steering angle based on a target steering angle set by the target angle setting unit.

Ra: Estimated outer radius of curvature
Dc ₀ : Proper road boundary distance
L: Distance from the vehicle width direction center line to the road boundary in the vehicle width direction

θ: Tire cut angle
WB: Vehicle wheelbase [m]

Θ: Target steering angle
N: Ratio of steering angle θ and tire angle θ (constant)

Ra: Estimated outer radius of curvature
Dc _n: curve within the appropriate road boundary distance
L: Distance from the vehicle width direction center line to the road boundary in the vehicle width direction

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