JP4094105B2 - Vehicle motion control device - Google Patents

Abstract

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

Description

そして、上記中点演算部１２ｅで演算した各データは、上記中点同距離点演算部１２ｆと上記曲率半径演算部１２ｇに出力されるようになっている。
【００３１】
上記中点同距離点演算部１２ｆは、上記長短判定部１２ｄから入力された距離が長い直線の各データ（位置、距離）と上記中点演算部１２ｅから入力された上記短い方の直線距離の半分の距離のデータから、上記長い方の直線上で上記第２の点から上記短い方の直線距離の半分の距離の位置に中点同距離点を決定するものである。ここで、上記第２の点Ｐn と上記第３の点Ｐn+1 を結ぶ直線を長い直線とし、中点同距離点をＰn,n+1 ＝（Ｘn,n+1 ，Ｙn,n+1 ）とすると、

上記中点同距離点演算部１２ｆで演算した中点同距離点Ｐn,n+1 の位置データは、上記曲率半径演算部１２ｇに出力されるようになっている。
【００３２】
上記曲率半径演算部１２ｇは、上記中点演算部１２ｅから入力された中点Ｐn-1,n の位置データと上記中点同距離点演算部１２ｆで演算した中点同距離点Ｐn,n+1 の位置データに基づき、図３に示すように、上記中点Ｐn-1,n で短い方の直線（ここではＰn-1 Ｐn ）に直交する直線と上記中点同距離点Ｐn,n+1 で長い方の直線（ここではＰn Ｐn+1 ）に直交する直線との交点位置を走行路のカーブの中心位置Ｏn と決定してこのカーブ中心位置Ｏn を基に走行路の曲率半径Ｒn を演算するように形成されている。この曲率半径演算部１２ｇで演算した結果は上記補正部１２ｈに出力されるようになっている。
【００３３】
すなわち、

上記（４），（５）式からＭを消去してＮを求めると、

そして、カーブ中心位置Ｏn は、

となる。
【００３４】
従って、曲率半径Ｒn は次式により求められる。
【００３５】

・（（Ｘon−Ｘn-1,n ）² ＋（Ｙon−Ｙn-1,n ）² ）^1/2 …（８）
ここで、曲率半径Ｒn が正の場合は左旋回、負の場合は右旋回となる。
【００３６】
また、上記カーブ中心位置Ｏn からカーブの代表点である上記第２の点Ｐn までの距離Ｌonは、以下の（９）式により求められる。
【００３７】
Ｌon＝（（Ｘon−Ｘn ）² ＋（Ｙon−Ｙn ）² ）^1/2 …（９）
上記補正部１２ｈは、上記曲率半径演算部１２ｇからの曲率半径Ｒn と上記カーブ中心位置Ｏn から上記第２の点Ｐn までの距離Ｌonとの差Ｄｅｌn を演算し、この差Ｄｅｌn が後述する誤差設定値を超える場合に、上記曲率半径Ｒn を補正して上記差Ｄｅｌn を上記誤差設定値にするものである。
【００３８】
この補正部１２ｈにより補正された、あるいは、上記差Ｄｅｌn が上記誤差設定値以下であり補正されなかった各点毎の最終的なカーブ情報（カーブの代表点Ｐn の位置（Ｘn ，Ｙn ），点Ｐn-1 と点Ｐn との距離Ｌn ，最終的な曲率半径Ｒn ，カーブ中心位置Ｏn ，直線Ｐn-1 Ｐn と直線Ｐn Ｐn+1 のなす角度から求められる各点のカーブ角度θn ，カーブ開始点Ｌsn（カーブ中心位置Ｏn から直線Ｐn-1 Ｐn に垂直に下ろした点）と点Ｐn-1 間の距離，車両位置から各カーブの代表点までの距離Ｌssn ）はメモリされ、前記データ整理部１２ｉに出力されるようになっている。
【００３９】
上記誤差設定値は、道路幅Ｄと短い方の直線距離の両方に応じて可変され、（誤差設定値）＝α・Ｄで設定されるようになっている（αは短い方の直線距離に応じて設定される定数：以後、点間隔補正係数と呼ぶ）。
【００４０】
上記道路幅Ｄには、通常、前記道路形状検出装置８から得られる道路幅の値を採用するようになっているが、上記道路形状検出装置８からデータが得られないときなどは、上記ナビゲーション装置７から得られる高速道路、一般国道、地方道というような道路種別情報を基に道路幅Ｄを設定するようになっている。ここで、道路幅Ｄが大きくなるほど上記誤差設定値が大きくなり補正を行わない方向になるが、これは、実際の道路で道路幅が大きくなるにつれて曲率半径Ｒn が大きくなることを表現するものである。
【００４１】
また、上記点間隔補正係数αは、短い方の直線距離が短い値ほど上記点間隔補正係数αは大きくなって誤差設定値が大きくなり補正を行わない方向になっている。例えば、短い方の直線距離が２０ｍ以下の短い場合はα＝１．２、１００ｍ以下の中距離の場合はα＝０．６、１００ｍより大きな場合はα＝０．３。これは、直線距離が短いということは、点データが細かく設定されており正しく道路を表現しているとみなせるため、補正を行わないようにするものである。
【００４２】
上記補正部１２ｈによる詳しい補正を図４に示す。Ｐn-1 からＰn へのベクトルをＢ１＝（Ｘn −Ｘn-1 ，Ｙn −Ｙn-1 ）＝（Ｘb1，Ｙb1）、Ｐ２からＰ３へのベクトルをＢ２＝（Ｘn+1 −Ｘn ，Ｙn+1 −Ｙn ）＝（Ｘb2，Ｙb2）とする。
【００４３】
Ｂ１とＢ２のなす角度θn は、
cos θn ＝（Ｘb1・Ｘb2＋Ｙb1・Ｙb2）／（｜Ｂ１｜・｜Ｂ２｜）
ＬonとＲn の誤差（比率）Ｐｄｅｌn は、

よって、ＬonとＲn の差Ｄｅｌn は次式のようになる。
【００４４】

ここで、差Ｄｅｌn が誤差設定値（α・Ｄ）を超える場合に、曲率半径Ｒn に対してＤｅｌn ＝α・Ｄとなるように補正が行われる。
すなわち、

このように上記カーブ形状検出部１２によりカーブ情報を得るため、ナビゲーション装置７からの一定間隔ではない点データをそのまま利用することができ、計算のためのデータの補完や、特に複雑な計算をすることなく簡単な演算処理で速やかに、かつ、正確に走行路の曲率半径を求めることができるのである。
【００４５】
また、曲率半径を求める各カーブ検出点間のつながりも自然で、実際の道路形状を正確に表現した値が得られる。
【００４６】
さらに、演算誤差も実際のカーブの曲率半径よりも小さめに生じるようになっており、例えばカーブ進入時の警報・減速制御において適切な警報を発する上で好ましいものとなっている。
【００４７】
また、曲率半径の補正部１２ｈを備えることにより、より正確な曲率半径の演算が可能になり、補正の基準に用いられる誤差設定値を実際の道路形状と点データの数で可変することにより、より一層正確な演算が行えるようになっている。すなわち、実際の道路で道路幅が大きくなるにつれて曲率半径が大きくなることを表現するため、道路幅が大きくなるほど誤差設定値が大きくなり補正を行わない方向になる。また、直線距離が短いということは、点データが細かく設定されており正しく道路を表現しているとみなせるため、短い方の直線距離が短い値ほど誤差設定値が大きくなり補正を行わない方向になる。
【００４８】
上記データ整理部１２ｉは、上記カーブ形状検出部１２で検出した各点毎のデータを整理するもので、整理されたデータの所定のデータが上記カーブ距離算出部１２ｊ，上記必要ヨーレート演算部１４に読み込まれて演算されるため、余分な演算の削減が行われるようになっている。
【００４９】
すなわち、上記ナビゲーション装置７からの点データは、１つのカーブを数点で表している場合があり、また、別々のカーブであっても一方のカーブを対象に制御を行えば他方のカーブについての制御を省略することができる場合がある。
【００５０】
従って、上記データ整理部１２ｉでは、上述のことを考慮し、各点データを点Ｐn-1 から点Ｐn に向かう場合について以下の４つのケースにあてはめて、必要な点データに整理するようになっている。
【００５１】
・ケース１…カーブはきつくなるが、点Ｐn-1 から点Ｐn に行くまでに減速距離（＝Ｒn-1 −Ｒn ）に余裕がある場合（図６（ａ））
｜Ｒn-1 ｜＞｜Ｒn ｜，Ｒn-1 ・Ｒn ＞０、かつ、Ｌn ＞｜Ｒn-1 ｜−｜Ｒn ｜ならば、点Ｐn-1 と点Ｐn のカーブ情報が必要。すなわち、点Ｐn-1 から点Ｐn に行くまでに減速に余裕があるため、点Ｐn-1 と点Ｐn の各々について独立した制御が必要になる。
【００５２】
また点Ｐn-1 と点Ｐn は１つのカーブを表していると考えて、この１つのカーブ角度（カーブ全角度θsn）を求めるために点Ｐn でのカーブ角度θn は加算する。

・ケース２…カーブはきつくなり、点Ｐn-1 から点Ｐn に行くまでに減速距離（＝Ｒn-1 −Ｒn ）に余裕が無い場合（図６（ｂ））
｜Ｒn-1 ｜＞｜Ｒn ｜，Ｒn-1 ・Ｒn ＞０、かつ、Ｌn ＜｜Ｒn-1 ｜−｜Ｒn ｜ならば、点Ｐn-1 のカーブ情報は無視（削減）。すなわち、点Ｐn のカーブについての制御を行うことで点Ｐn-1 のカーブについての制御が吸収されてしまい、点Ｐn-1 のカーブ情報は無駄になるため無視（削減）する。
【００５３】
また点Ｐn-1 と点Ｐn は１つのカーブを表していると考えて、この１つのカーブ角度（カーブ全角度θsn）を求めるために点Ｐn でのカーブ角度θn は加算する。

・ケース３…カーブが緩くなる場合（図６（ｃ））
｜Ｒn-1 ｜＜｜Ｒn ｜，Ｒn-1 ・Ｒn ＞０
ならば、点Ｐn のカーブ情報は無視（削減）。すなわち、点Ｐn-1 で速度は減速されるようになっているため、この点Ｐn-1 よりも緩いカーブである点Ｐn のカーブ情報は不要になり無視（削減）する。尚、Ｌn が長い場合、十分に加速してしまうと（点Ｐn-1 と点Ｐn とが独立したカーブとみなせるなら）、点Ｐn に着くまでに車速が大きくなってしまうことも考えられるので、Ｌn の大きさに応じて点Ｐn のカーブ情報は保持するようにしても良い。
【００５４】
また点Ｐn-1 と点Ｐn は１つのカーブを表していると考えて、この１つのカーブ角度（カーブ全角度θsn）を求めるために点Ｐn でのカーブ角度θn は加算する。

尚、点Ｐn-1 と点Ｐn とが独立したカーブとみなせるなら点Ｐn でのカーブ角度θn は加算せず、新たに加算を始める（Ｌn の大きさに応じて決定する）。
【００５５】
・ケース４…カーブの旋回方向が切り替わる場合（図６（ｄ））
Ｒn-1 ・Ｒn ＜０
ならば、点Ｐn のカーブ情報は必要。すなわち、点Ｐn-1 から点Ｐn に行く際は、旋回方向が異なるため、ここだけでのデータの整理は行わない。
【００５６】
また、点Ｐn-1 まで続いてきたカーブ角度の合計を、点Ｐn-1 までのカーブ全角度θs(n-1)とする。
【００５７】
さらに、点Ｐn からのカーブ全角度θsnを求めるために加算を始める。
点Ｐn までのカーブ全角度θsn＝２・cos^-1 （Ｒn ／Ｌon）
尚、上記各ケースにあてはめて、１つの点に対し必要とする場合と不要とする場合とが重なった際には、その点は無視（削減）する。
【００５８】
ここで、減速距離を、カーブの曲率半径Ｒn とＲn-1 の差で計算したのは、以下のためである。点Ｐn における基準許容進入速度をＶpn、減速度をａ、許容横加速度をａyln として、

減速度ａを許容横加速度ａylの５０％の（１／２）・ａylとすると、
減速距離＝Ｒn-1 −Ｒn
この結果から、減速距離をカーブの曲率半径Ｒn とＲn-1 の差で計算したのである。
【００５９】
上記カーブ距離算出部１２ｊは、上記データ整理部１２ｉからのデータ、上記ナビゲーション装置７からの自己（自車両）位置データが入力され、走行路前方カーブの入口から自車両までの距離ｌcを算出するようになっている。
【００６０】
上記制御開始判定・制御部１３は、制御開始判定・制御手段として形成され、上記車速Ｖ，上記ヨーレート応答時間演算部１１で演算されたヨーレート応答時間ｔr，及び，上記カーブ検出部１２で検出された車両から前方カーブ入口までの距離ｌcを示すデータが入力され、上記車速Ｖと上記カーブ入口までの距離ｌcとを基に車両が上記前方カーブに到達するまでの時間ｔcを算出するとともに、このカーブ入口までの到達時間ｔcと上記ヨーレート応答時間ｔrとを比較することによって、上記前方カーブに対する運動制御を開始するタイミングを判定し、この運動制御開始タイミングで、上記制動力制御装置９または上記警報装置１０の少なくともどちらか一方に上記制御開始信号を出力するようになっている。
【００６１】
すなわち、上記制御開始判定・制御部１３では、上記カーブ入口までの到達時間ｔcを、
カーブまでの到達時間ｔc＝（カーブ入口までの距離ｌc）／（車速Ｖ）…（１３）
によって算出し、この算出したカーブまでの到達時間ｔcが上記ヨーレート応答時間ｔr以下となったときを上記前方カーブに対する運動制御開始タイミングとして、上記制動力制御装置９または上記警報装置１０の少なくともどちらか一方に上記制御開始信号を出力するようになっている。
【００６２】
ここで、上記制御開始判定・制御部１３では、上記車速Ｖと上記ヨーレート応答時間ｔrとを基にヨーレート応答距離ｌr（ドライバのハンドル操舵に対してヨーレートが応答するまでに車両が走行する距離）を求め、このヨーレート応答距離ｌrと上記カーブまでの距離ｌcとを比較することによって上記前方カーブに対する運動制御開始タイミングを判定してもよい。この場合、上記ヨーレート応答距離ｌrは、
ヨーレート応答距離ｌr＝（車速Ｖ）・（ヨーレート応答時間ｔr）…（１４）
によって算出され、このヨーレート応答距離ｌrが上記コーナ入口までの距離ｌc以上となったときが上記運動制御開始タイミングとなる。
【００６３】
このように、上記前方カーブに対する運動制御開始タイミングをヨーレート応答時間ｔrを基に判定することで、上記前方カーブに対する運動制御を該運動制御に対する車両の応答性を考慮した適切なタイミングに設定することができる。
【００６４】
上記必要ヨーレート演算部１４は、許容横加速度算出部１４ａと必要ヨーレート算出部１４ｂから主要に構成されている。
【００６５】
上記許容横加速度算出部１４ａは、例えば、上記車速センサ３から車速Ｖ、上記前後加速度センサ６から前後加速度、上記車両諸元算出部１１ａから路面摩擦係数推定値μ、上記カーブ形状検出部１２から前方カーブのカーブ角度とカーブ方向が入力され、上記路面摩擦係数推定値μに応じて許容横加速度の基本値ａyl1nを演算するとともに、この許容横加速度の基本値ａyl1nを上記車速Ｖ，道路勾配ＳＬ，カーブ角度とカーブ方向で所定に補正して許容横加速度ａylnを算出するようになっている。なお、上記道路勾配ＳＬは、上記車速Ｖの変化率と上記前後加速度を基に算出されるものである。
【００６６】
上記必要ヨーレート算出部１４ｂは、上記カーブ形状検出部１２，上記許容横加速度算出部１４ａから上記前方カーブのカーブ半径Ｒn，許容横加速度ａylnが入力され、上記前方カーブにおける必要ヨーレート（ｄΨ／ｄｔ）を
必要ヨーレート（ｄΨ／ｄｔ）＝ ((カーブでの許容横加速度ａyln ）／（カーブ半径Ｒn))^1/2…（１５）
によって算出し、上記制動力制御装置９に出力するようになっている。
【００６７】
上記制動力制御装置９は、現在の車速Ｖ、ハンドル角θH、ヨーレートγが入力され、上記各入力信号を基に目標ヨーレートの微分値、低μ路走行の予測ヨーレートの微分値及び両微分値の偏差を算出し、またヨーレートγと目標ヨーレートとの偏差を算出し、これらの値に基づいて、車両のアンダーステア傾向、あるいは、オーバーステア傾向を修正する目標制動力を算出し、車両のアンダーステア傾向を修正するためには旋回方向内側後輪を、オーバーステア傾向を修正するためには旋回方向外側前輪を制動力を加える制動輪として選択し、図示しないブレーキ駆動部に制御信号を出力して上記選択車輪に目標制動力を付加して制動力制御するように形成されている。
【００６８】
ここで、上記制動力制御装置９は、上記制御部２の制御開始判定・制御部１３から上記制御開始信号が入力されたとき、上記必要ヨーレート算出部１４ｂで算出された前方カーブでの上記必要ヨーレート（ｄΨ／ｄｔ）を目標ヨーレートとして設定し、この設定された目標ヨーレートを基に制動力制御を行うようになっている。
【００６９】
すなわち、上記制動力制御装置９では、カーブ走行時以外には現在の走行状況に応じて車両の挙動制御を行い、一方、カーブ走行の際は、カーブ進入前の所定のタイミングで上記制御開始信号が入力されると、上記必要ヨーレート（ｄΨ／ｄｔ）を目標ヨーレートとして設定することで上記前方カーブの道路状況に応じた車両挙動制御を行う。
【００７０】
なお、上記車両の挙動を制御する装置としては、上記制動力制御装置９に限らず、例えば、ヨーレートを制御則パラメータとして用いる四輪操舵車では、上記制御部２を四輪操舵制御装置に接続し、この四輪操舵制御装置に上記制御部２から制御開始信号が入力されたとき、上記制動力制御装置９と同様に必要ヨーレート（ｄΨ／ｄｔ）を目標ヨーレートとして設定してヨー角速度比例操舵制御や前輪比例操舵を行ってもよいし、また、これらを組み合わせた制御等を行ってもよい。さらに、上記制動力制御装置９と上記四輪操舵制御装置とを組み合わせた構成としてもよい。
【００７１】
上記警報装置１０は、運転者に対して警報を行いブレーキ操作やハンドル操舵等の制御を促すことによって走行路前方のカーブを走行する際の安全を維持するものであり、上記制御部２からの制御開始信号が入力されると図示しない所定の警報手段を駆動してブザー、音声警報発生、警告灯等の警報を行うようになっている。すなわち、この警報装置１０は、上記前方カーブに対して制御開始信号が入力されるタイミングに応じて警報を発することにより、車両の挙動遅れを考慮した所定分だけ早めの、適切なタイミングでの警報が行われる。
【００７２】
次に、本発明の第１の実施の形態による前方カーブに対する車両運動制御開始タイミングの判定制御を図７のフローチャートで説明する。このプログラムは、例えば、所定時間毎に実行され、プログラムがスタートすると、ステップ（以下Ｓと略称）１０１で、車速センサ３，ハンドル角センサ４，ヨーレートセンサ５，前後加速度センサ６から、車速Ｖ，ハンドル角θH，ヨーレートγ，前後加速度の各信号を読込むとともに、ナビゲーション装置７から点データ及び道路種別情報，道路形状検出装置８から道路幅データを読込み、Ｓ１０２に進む。
【００７３】
上記Ｓ１０２では、車両諸元算出部１１ａで、車速Ｖ，ハンドル角θH，ヨーレートγを基にコーナリングパワＫf，Ｋrを推定し、このコーナリングパワＫf，Ｋrを用いて路面摩擦係数推定値μを算出し、Ｓ１０３に進む。
【００７４】
上記Ｓ１０３では、ヨーレート応答時間算出部１１ｂで、上記車速Ｖ，上記路面摩擦係数推定値μを基に前記（１）式によりヨーレート応答時間ｔrを算出し、Ｓ１０４に進む。
【００７５】
上記Ｓ１０４では、カーブ形状検出部１２で、上記ナビゲーション装置７からの点データ及び道路種別情報と上記道路形状検出装置８からの道路幅データとを基に走行路前方のカーブを検出し、この検出した前方カーブの入口までの距離ｌcを算出して、Ｓ１０５に進む。
【００７６】
上記Ｓ１０５では、必要ヨーレート演算部１４で、上記車速Ｖ，上記路面摩擦係数推定値μ，前方カーブのカーブ角度とカーブ方向を基に許容横加速度ａylnを算出し、この許容横加速度ａylnと前方カーブのカーブ半径Ｒnとを基に前記（１５）式により必要ヨーレート（ｄΨ／ｄｔ）を算出して、Ｓ１０６に進む。
【００７７】
上記Ｓ１０６では、制御開始判定・制御部１３で、上記車速Ｖ，上記前方カーブ入口までの距離ｌcを基に前記（１３）式によりカーブまでの到達時間ｔcを算出し、このカーブまでの到達時間ｔcと上記ヨーレート応答時間ｔrとを比較して、上記カーブまでの到達時間ｔcが上記ヨーレート応答時間ｔrよりも大きいとき、上記車両運動制御開始タイミングでないと判定し、Ｓ１０１に戻る。
【００７８】
一方、上記Ｓ１０６で、上記カーブまでの到達時間ｔcか上記ヨーレート応答時間ｔr以下であるとき、上記車両運動制御開始タイミングであると判断し、Ｓ１０７に進み、制動力制御装置９と警報装置１０に、上記前方カーブに対する車両運動制御を開始するるための所定の信号（制御開始信号）を出力した後ルーチンを抜ける。
【００７９】
ここで、上記制動力制御装置９に上記制御開始信号が入力されると、上記必要ヨーレート算出部１４ｂで算出された前方カーブにおける必要ヨーレートを目標ヨーレートとして設定し、この目標ヨーレートを基に制動力制御を行う。すなわち、ヨーレート応答時間に基づいて車両の応答遅れを考慮した運動制御開始タイミングを判定することで、カーブ進入前の適切なタイミングで上記制御開始信号が入力され、該制御開始信号が入力されると、上記必要ヨーレート（ｄΨ／ｄｔ）を目標ヨーレートとして設定して上記前方カーブの道路状況に応じた車両挙操制御をカーブ進入前に適切なタイミングで予め行うので、カーブ進入時には最適な車両走行状態を維持することができ、高いレベルでの安全維持を実現することができる。
【００８０】
また、上記警報装置１０に上記制御開始信号が入力されると、該警報装置１０では、図示しない警報手段を駆動してブザー，音声警報発生，警告灯等の警報を行い、運転者にハンドル操舵，ブレーキ制御等の所定の操作を促す。すなわち、ヨーレート応答時間に基づいて車両の応答遅れを考慮した運動制御開始タイミングを判定することで、カーブ進入前の適切なタイミングで上記制御開始信号が入力され、該制御開始信号が入力されると、所定の警報を発して運転者に上記前方カーブに対する車両制御を予め促すことができ、高いレベルでの安全維持を実現することができる。
【００８１】
このように、本実施の形態によれば、車速Ｖと路面摩擦係数推定値μを基にヨーレート応答時間を算出し、このヨーレート応答時間に基づいて車両のヨーレートの応答遅れを考慮した運動制御開始タイミングを判定することができるので、前方カーブに対する車両の運動制御を適切なタイミングで行うことができ、高いレベルでの安全維持を実現することがきる。
【００８２】
次に、図８〜１０は、本発明の第２の実施の形態を示し、図８は、車両運動制御装置の全体構成を示すブロック図、図９は、ヨーレート応答時間補正係数と必要ヨーレートの特性の説明図、図１０は、前方カーブに対する車両運動制御開始判定のフローチャートである。なお、上述の第１の実施の形態では、ヨーレート応答時間演算部１１は車両諸元算出部１１ａとヨーレート応答時間算出部１１ｂとで主要に構成され、上記車両諸元算出部１１ａで路面摩擦係数推定値μを算出し、上記ヨーレート応答時間算出部１１ｂで車速Ｖ及び上記路面摩擦係数推定値μを基にヨーレート応答時間ｔrを算出したのに対し、本実施の形態では、ヨーレート応答時間演算部１７は車両諸元算出部１７ａとヨーレート応答時間基準値算出部１７ｂとヨーレート応答時間基準値補正部１７ｃとで主要に構成され、上記車両諸元算出部１７ａで路面摩擦係数推定値μを算出し、上記ヨーレート応答時間基準値算出部１７ｂで車速Ｖ及び上記路面摩擦係数推定値μを基にヨーレート応答時間基準値ｔr1を算出し、上記ヨーレート応答時間基準値補正部１７ｃで上記ヨーレート応答時間基準値ｔr1を必要ヨーレート（ｄΨ／ｄｔ）を用いて補正してヨーレート応答時間ｔrを算出するものである。その他の制御は上述の第１の実施の形態と略同様であり、これらの制御を行う各構成については同符号を付して説明を省略する。
【００８３】
上記車両諸元算出部１７ａは、上述の第１の実施の形態で示した車両諸元算出部１１ａと同様、車速センサ３からの車速Ｖ，ハンドル角センサ４からのハンドル角θH，ヨーレートセンサ５からのヨーレートγを示すデータが入力され、これらを基に前後輪のコーナリングパワＫf，Ｋrを推定し、路面摩擦係数推定値μを推定するようになっている。
【００８４】
上記ヨーレート応答時間基準値算出部１７ｂは、上記車速センサ３から車速Ｖ及び上記車両諸元算出部１１ａから路面摩擦係数推定値μが入力され、これらを基に車両のヨーレート応答時間基準値ｔr1を算出するようになっている。ここで、上記ヨーレート応答時間基準値ｔr1の算出は、上述の第１の実施の形態のヨーレート応答時間算出部１１ｂにおけるヨーレート応答時間ｔrの算出方法，すなわち，前記（１）式により算出する方法と同様である。
【００８５】
上記ヨーレート応答時間基準値補正部１７ｃは、必要ヨーレート算出部１４ｂ，上記ヨーレート応答時間基準値算出部１７ｂからの必要ヨーレート（ｄΨ／ｄｔ），ヨーレート応答時間基準値ｔr1を示すデータが入力され、上記必要ヨーレート（ｄΨ／ｄｔ）に応じて上記ヨーレート応答時間基準値ｔr1を補正してヨーレート応答時間ｔrを算出し、制御開始判定・制御部１３に出力するようになっている。
【００８６】
すなわち、上記ヨーレート応答時間基準値補正部１７ｃでは、上記ヨーレート応答時間ｔrは、例えば、次式によって算出する。

ここで、上記補正係数Ｋは、例えば、図９に示すように、必要ヨーレート（ｄΨ／ｄｔ）が大きくなると線形的に大きくなるように予め定めれられる係数である。すなわち、これは、ヨーレート応答の時定数が車両諸元で決まるものの、ドライバの操舵速度を考えると大きく操舵する必要のある場合はそれなりに車両運動制御を開始する必要がある。このため、ヨーレート応答時間ｔrを大きめに設定することでカーブまでの到達時間が大きくても制御を開始するようになることを表現するものである。
【００８７】
次に、本発明の第２の実施の形態による前方カーブに対する車両運動制御開始タイミング判定の制御を図１０のフローチャートで説明する。このプログラムは、例えば、所定時間毎に実行され、プログラムがスタートすると、ステップＳ２０１で、車速センサ３，ハンドル角センサ４，ヨーレートセンサ５，前後加速度センサ６から、車速Ｖ，ハンドル角θH，ヨーレートγ，前後加速度の各信号を読込むとともに、ナビゲーション装置７から点データ及び道路種別情報，道路形状検出装置８から道路幅データを読込み、Ｓ２０２に進む。
【００８８】
上記Ｓ２０２では、車両諸元算出部１７ａで、車速Ｖ，ハンドル角θH，ヨーレートγを基にコーナリングパワＫf，Ｋrを推定し、このコーナリングパワＫf，Ｋrを用いて路面摩擦係数推定値μを算出し、Ｓ２０３に進む。
【００８９】
上記Ｓ２０３では、ヨーレート応答時間基準値算出部１７ｂで、上記車速Ｖ，上記路面摩擦係数推定値μを基にヨーレート応答時間基準値ｔr1を前記（１）式におけるｔrをｔr1に読み代えて算出し、Ｓ２０４に進む。
【００９０】
上記Ｓ２０４では、カーブ形状検出部１２で、上記ナビゲーション装置７からの点データ及び道路種別情報と上記道路形状検出装置８からの道路幅データとを基に走行路前方のカーブを検出し、この検出した前方カーブの入口までの距離ｌcを算出して、Ｓ２０５に進む。
【００９１】
上記Ｓ２０５では、必要ヨーレート演算部１４で、上記車速Ｖ，上記路面摩擦係数推定値μ，前方カーブのカーブ角度とカーブ方向を基に許容横加速度ａylnを算出し、この許容横加速度ａylnと前方カーブのカーブ半径Ｒnとを基に前記（１５）式により必要ヨーレート（ｄΨ／ｄｔ）を算出して、Ｓ２０６に進む。
【００９２】
上記Ｓ２０６では、ヨーレート応答時間基準値補正部１７ｃで、必要ヨーレート（ｄΨ／ｄｔ）に応じて上記ヨーレート応答時間基準値ｔr1を補正して前記（１６）式でヨーレート応答時間ｔrを算出し、上記Ｓ２０７に進む。
【００９３】
上記Ｓ２０７では、制御開始判定・制御部１３で、上記車速Ｖ，上記前方カーブ入口までの距離ｌcを基に前記（１３）式によりカーブまでの到達時間ｔcを算出し、このカーブまでの到達時間ｔcと上記ヨーレート応答時間ｔrとを比較して、上記カーブまでの到達時間ｔcが上記ヨーレート応答時間ｔrよりも大きいとき、上記車両運動制御開始タイミングでないと判定し、Ｓ２０１に戻る。
【００９４】
一方、上記Ｓ２０７で、上記カーブまでの到達時間ｔcか上記ヨーレート応答時間ｔr以下であるとき、上記車両運動制御開始タイミングであると判断し、Ｓ２０８に進み、制動力制御装置９と警報装置１０に、上記前方カーブに対する車両運動制御を開始するるための所定の信号（制御開始信号）を出力した後ルーチンを抜ける。
【００９５】
このように、本実施の形態では、車速Ｖ，車両後輪のコーナリングパワＫr，路面摩擦係数推定値μからヨーレート応答時間基準値ｔr1を求め、このヨーレート応答時間基準値ｔr1を必要ヨーレート（ｄΨ／ｄｔ）に応じて補正することで、上述の第１の実施の形態で求めたヨーレート応答時間ｔrよりもより正確なヨーレート応答時間ｔrを算出することができる。
【００９６】
次に、図１１〜図１４は本発明の第３の実施の形態を示し、図１１は、車両運動制御装置の全体構成を示すブロック図、図１２は、制御開始判定・制御部の説明図、図１３は、車両運動制御のフローチャート、図１４は、制御開始判定のサブルーチンのフローチャートである。なお本実施の形態は、本出願人が特願平９ー２４５７８８号に示した車両運動制御を車両のヨーレート応答を考慮して行うものである。
【００９７】
図１１において、符号１ｂは車両に搭載される車両運動制御装置の全体構成を示し、この車両運動制御装置１ｂの制御部２ｂには、車速センサ３、ハンドル角センサ４、ヨーレートセンサ５、前後加速度センサ６の各センサで検出した車速Ｖ、ハンドル角θH、ヨーレートγ、前後加速度の各信号、及び、ナビゲーション装置７から道路データの点データや道路種別情報、道路形状検出装置８から道路幅等の道路の形状に関するデータ、ターンシグナルスイッチ３１からの動作信号（運転者の旋回操作を示す信号）が入力されるようになっている。
【００９８】
上記制御部２ｂは、上記各センサ３，４，５，６、上記ナビゲーション装置７、上記道路形状検出装置８、上記ターンシグナルスイッチ３１からの各入力に基づき、走行路前方のカーブを十分に安定して曲がれるか否かを演算し、必要に応じて運転者に対して、ブザー、音声警報発生、警告灯等の警報装置３５を通じた警報を行うとともに、強制的な減速が必要な場合（強制減速時）には、警報に加え、トランスミッション制御装置３２に対してシフトダウンの実行、エンジン制御装置３３に対して過給圧ダウン、燃料カットおよびスロットル開度全閉（閉制御）の実行、ブレーキ制御装置３４に対してブレーキ作動、ブレーキ力増加の実行を行わせるようになっている（警報・減速制御を行うようになっている）。ここで、本実施の形態では上記各装置３２〜３５による車両挙動制御や警報出力は、車両のヨーレート応答距離を考慮したタイミングで行われる。
【００９９】
上記トランスミッション制御装置３２は、車両の変速制御、ロックアップ制御、ライン圧制御等のトランスミッションに係る制御を行うもので、上記制御部２ｂに対しては現在のシフト位置を出力するとともに、上記制御部２ｂからのシフトダウン実行の信号が入力されるとシフトダウンを行うようになっている。
【０１００】
上記エンジン制御装置３３は、燃料噴射制御、点火時期制御、空燃比制御、過給圧制御、スロットル開度制御等のエンジンに係る制御を行うもので、上記制御部２ｂに対しては過給圧制御情報、燃料カット情報、スロットル開度制御情報を出力するとともに、上記制御部２ｂから、過給圧ダウン実行の信号が入力されると過給圧ダウンを、燃料カット実行の信号が入力されると燃料カットを、スロットル開度全閉（閉制御）実行の信号が入力されるとスロットル開度全閉（閉制御）を行うようになっている。
【０１０１】
上記ブレーキ制御装置３４は、ハイドロリックユニットが連接されてアンチロックブレーキ制御、自動ブレーキ制御等を行うもので、上記制御部２ｂに対しては現在のブレーキ作動状態を出力するとともに、上記制御部２ｂから、ブレーキ作動、ブレーキ力増加の実行の信号が入力されると、ブレーキ作動、ブレーキ力増加を行うようになっている。
【０１０２】
上記警報装置３５は、チャイム・ブザー、音声警報発生、警告灯等、あるいは、これらの組み合わせにより構成されており、例えば、警報時には、上記ナビゲーション装置７のＣＤ−ＲＯＭに予め録音しておいた「カーブのため減速して下さい。」等の音声警報、あるいはチャイム・ブザー音のみの警報を行い、強制減速時には、「カーブのため減速します。」等の音声警報とブザーと警告灯の点灯を行うようになっている。尚、警報の仕方はこれに限らず、その他、複数の音声警告を使い分けて警報時と強制減速時の警告を行う等であっても良い。また、警報・減速の制御対象となるカーブの位置を上記ナビゲーション装置７の情報表示部（図示せず）の地図上に色表示したり、あるいは音声で案内したりしても良い。
【０１０３】
上記制御部２ｂは、ヨーレート応答時間演算部１１、カーブ形状検出部１２、許容横加速度算出部３６、制御開始判定・制御部３８から主に構成されている。
【０１０４】
上記許容横加速度算出部３６は、例えば、上記車速センサ３から車速Ｖ、上記前後加速度センサ６から前後加速度、上記車両諸元算出部１１ａから路面摩擦係数推定値μ、上記カーブ形状検出部１２から前方カーブのカーブ角度とカーブ方向が入力され、上記路面摩擦係数推定値μに応じて許容横加速度の基本値ａyl1nを演算するとともに、この許容横加速度の基本値ａyl1nを上記車速Ｖ，道路勾配ＳＬ，カーブ角度とカーブ方向で所定に補正して許容横加速度ａylnを算出するようになっている。なお、上記道路勾配ＳＬは、上記車速Ｖの変化率と上記前後加速度を基に算出されるものである。
【０１０５】
上記制御開始判定・制御部３８は、上記車速センサ３から車速Ｖ、上記ハンドル角センサ４からハンドル角θH、上記前後加速度センサ６から前後加速度、上記車両諸元算出部１１ａから路面摩擦係数推定値μ、上記ヨーレート応答時間算出部１１ｂからヨーレート応答時間ｔr、上記カーブ形状検出部１２からカーブ半径Ｒn、上記ターンシグナルスイッチ３１から動作信号、上記許容横加速度算出部３６から許容横加速度ａyln、これら各入力に応じて、警報制御を行うべく信号を上記警報装置３５に出力するとともに、減速制御を行うべく信号を上記各制御装置３２〜３４に所定に出力するようになっている。
【０１０６】
詳しく説明すると、上記制御開始判定・制御部３８は、図１２に示すように、基準許容進入速度設定部４０、許容減速度設定部４１、制御実行判断部４２、減速速度演算・出力部４３、警報速度演算・出力部４４で主に構成されている。
【０１０７】
上記ヨーレート応答距離算出部３７は、上記車速センサ３から車速Ｖ、ヨーレート応答時間算出部１１ｂからヨーレート応答時間ｔrが入力され、例えば、上述の第１の実施の形態で示した（１４）式によってヨーレート応答距離ｌrを算出するようになっている。
【０１０８】
上記基準許容進入速度設定部４０は、上記カーブ形状検出部１２からのカーブの曲率半径Ｒn と上記許容横加速度算出部３６からの許容横加速度ａyln を基に基準とする許容進入速度（基準許容進入速度Ｖpn）を設定するようになっており、各設定した基準許容進入速度Ｖpnは、上記減速速度演算・出力部４３と上記警報速度演算・出力部４４に出力するようになっている。
【０１０９】
この基準許容進入速度設定部４０での基準許容進入速度Ｖpnの演算は以下の式により行われる。
Ｖpn＝（ａyln ・Ｒn ）^1/2 …（１７）
【０１１０】
上記許容減速度設定部４１は、路面摩擦係数推定値μと道路勾配ＳＬの道路状況に応じて車両が許容できる減速度（許容減速度ＸgLim）を設定し、この許容減速度ＸgLimは、上記減速速度演算・出力部４３、上記警報速度演算・出力部４４に出力されるようになっている。
【０１１１】
すなわち、上記許容減速度設定部４１では、先ず、例えば以下により、上記車両諸元算出部１１ａで算出した路面摩擦係数推定値μから基本値ＸgLim0を設定するようになっている。
ＸgLim0 ＝μ・g・Ｋμ2 …（１８）
ここで、係数Ｋμ2 はフルブレーキング時の路面利用率を考慮し、例えばＫμ2 ＝０．８程度の値とする。また、定数ａxcは実験・計算等により予め設定しておいたもので、例えば５m/s²等の値をとるものとする。
【０１１２】
さらに、上記許容減速度設定部４１では、以下（１９）式に示すように、道路勾配ＳＬによる制動距離の変化に対する補正を加え、同時に、運転者の感じる減速加速度が一定になるように、登り勾配では大きい減速度、下り勾配では小さい減速度になるように上記基本値ＸgLim0 を補正して、許容減速度ＸgLimを求めるようになっている。このような補正により、上り坂では勾配による重力の減速成分、下り坂では重力の加速成分を考慮した制御開始タイミングとなる。
ＸgLim＝ＸgLim0 ＋ｇ・ＳＬ／１００ …（１９）
【０１１３】
上記制御実行判断部４２は、上記ターンシグナルスイッチ３１、上記車速センサ３からの信号と上記ハンドル角センサ４からの信号が入力されるようになっており、これら信号により、警報制御の解除（ＯＦＦ）、警報・減速制御の解除（ＯＦＦ）、減速制御から警報制御への変更を判定して上記減速速度演算・出力部４３、上記警報速度演算・出力部４４に出力するようになっている。
【０１１４】
すなわち、運転者が上記ターンシグナルスイッチ３１の操作をした場合は、上記ナビゲーション装置７の地図情報にない直線路への進入、あるいは、カーブと交差点の誤判断が予想されるので、警報・減速制御の解除を行うようになっている。
【０１１５】
また、上記ハンドル角センサ４からの信号により、運転者が予め設定しておいた操舵量以上のハンドル操作を行った場合は、想定しているコース以外の走行が予想されるので、警報・減速制御の解除を行うようになっている。
【０１１６】
上記車速センサ３からの信号により、警報制御を行う際に、運転者が警報判定での減速度（０．５・ＸgLim）以上の減速を既に行っている場合は、運転者は既に対処中であり、警報をする必要がないため警報制御の解除を行うようになっている。尚、この場合、複数の警報の仕方が変化できるならば、警報の仕方を変えて警報を行うようにしても良い。
【０１１７】
また、上記車速センサ３からの信号により、減速制御を行う際に、運転者が減速判定での減速度（０．８・ＸgLim）以上の減速を既に行っている場合は、運転者は既に対処中であり、強制減速をする必要がないため減速制御を警報制御に変更させるようになっている。
【０１１８】
上記警報速度演算・出力部４４は、上記カーブ距離検出部１２から車両前方の各点，…，Ｐn-1，Ｐn，…，のデータが入力され、これら各点間の距離Ｌnが算出されるとともに、上記距離Ｌnと、上記許容減速度設定部４１で設定した許容減速度ＸgLimと、上記基準許容進入速度設定部４０で設定した基準許容進入速度Ｖpnとに基づき、警報制御の基準とする許容進入速度を警報速度ＶA として演算するようになっている。この警報速度演算・出力部４４で演算した各警報速度ＶA は、後述する減速速度ＶB と共に所定にメモリされるようになっている。
【０１１９】
さらに、上記警報速度演算・出力部４４には、上記ヨーレート応答距離算出部３７からヨーレート応答距離ｌrが入力され、例えば、上記ヨーレート応答距離ｌrを考慮した警報に対する閾値を減速可能な加速度、すなわち許容減速度ＸgLimに対する５０％の速度として設定するようになっている。
【０１２０】
先行点Ｐ２に対する到着点Ｐ１（点Ｐ２〜点Ｐ１＝Ｌ2 ）での警報の判断速度（警報速度ＶA ＝ＶＡ１２）は、点Ｐ２での通過可能速度（＝基準許容進入速度Ｖp2）に対して、
ＶＡ１２＝（Ｖp2² ＋２・（０．５・ＸgLim）・（Ｌ2−ｌr） ）^1/2
同様に、先行点Ｐ３に対する到着点Ｐ１（点Ｐ３〜点Ｐ１＝Ｌ2 ＋Ｌ3 ）での警報速度ＶA （＝ＶＡ１３）は基準許容進入速度Ｖp3に対して、
ＶＡ１３＝（Ｖp3² ＋２・（０．５・ＸgLim）・（Ｌ2 ＋Ｌ3−ｌr））^1/2
而して先行点Ｐβに対する到着点Ｐα（点Ｐβ〜点Ｐα＝Ｌ（α＋１）＋…＋Ｌβ）での警報速度ＶA （＝ＶＡαβ）は基準許容進入速度ＶＰβに対して、
ＶＡαβ＝（ＶＰβ² ＋２・（０．５・ＸgLim）・（Ｌ（α＋１）＋…＋Ｌβ−ｌr））^1/2 …（２０）
さらに、上記警報速度演算・出力部４４では、上記距離Ｌ1 、許容減速度ＸgLimにより、上記各警報速度ＶＡ１β（ＶＡ１（n+1 ）〜Ｖp1）をそれぞれ現在位置点Ｐ０における警報速度に変換して推定警報速度ＶＡＰとして演算し、この推定警報速度ＶＡＰと車速Ｖとをそれぞれ比較して車速Ｖが推定警報速度ＶＡＰ以上の際に警報制御を行うべく信号を上記警報装置３５に出力するようになっている。警報制御の実行は、上記制御実行判断部４２からの信号により解除、あるいは減速制御からの変更による開始が可能になっている。
【０１２１】
ここで上記推定警報速度ＶＡＰは、以下のように算出される。
上記（２０）式より、先行点Ｐβに対する到着点Ｐ０（点Ｐβ〜点Ｐ０＝Ｌ1 ＋Ｌ2 ＋…＋Ｌβ）での警報速度ＶA （＝ＶＡ０β＝ＶＡＰ）は基準許容進入速度ＶＰβに対して、
ＶＡＰ＝（ＶＰβ² ＋２・（０．５・ＸgLim）・（Ｌ1 ＋Ｌ2 ＋…＋Ｌβ−ｌr ））^1/2
また、先行点Ｐβに対する到着点Ｐ１（点Ｐβ〜点Ｐ１＝Ｌ2 ＋…＋Ｌβ）での警報速度ＶA （＝ＶＡ１β）は基準許容進入速度ＶＰβに対して、
ＶＡ１β＝（ＶＰβ² ＋２・（０．５・ＸgLim）・（Ｌ2 ＋…＋Ｌβ−ｌr））^1/2
従って、これら２つの式から、
ＶＡＰ＝（ＶＡ１β² ＋２・（０．５・ＸgLim）・（Ｌ1−ｌr ） ）^1/2 …（２１）
【０１２２】
上記減速速度演算・出力部４３は、上記カーブ距離検出部１２から車両前方の各点，…，Ｐn-1，Ｐn，…，のデータ、が入力されてこれら各点間の距離Ｌnが算出されるとともに、上記許容減速度設定部４１で設定した許容減速度ＸgLimと、上記基準許容進入速度設定部４０で設定した基準許容進入速度Ｖpnとが入力され、減速制御の基準とする許容進入速度を減速速度ＶB として演算するようになっている。
【０１２３】
さらに、上記減速速度演算・出力部４３には、上記ヨーレート応答距離算出部３７からヨーレート応答距離ｌrが入力され、例えば、上記ヨーレート応答距離ｌrを考慮した強制減速に対する閾値を減速可能な加速度、すなわち許容減速度ＸgLimに対する８０％の速度として設定するようになっている。
【０１２４】
先行点Ｐ２に対する到着点Ｐ１（点Ｐ２〜点Ｐ１＝Ｌ2 ）での強制減速の判断速度（減速速度ＶB ＝ＶＢ１２）は、点Ｐ２での通過可能速度（＝基準許容進入速度Ｖp2）に対して、
ＶＢ１２＝（Ｖp2² ＋２・（０．８・ＸgLim）・（Ｌ2−ｌr））^1/2
同様に、先行点Ｐ３に対する到着点Ｐ１（点Ｐ３〜点Ｐ１＝Ｌ2 ＋Ｌ3 ）での減速速度ＶB （＝ＶＢ１３）は基準許容進入速度Ｖp3に対して、
ＶＢ１３＝（Ｖp3² ＋２・（０．８・ＸgLim）・（Ｌ2 ＋Ｌ3 −ｌr））^1/2 而して先行点Ｐβに対する到着点Ｐα（点Ｐβ〜点Ｐα＝Ｌ（α＋１）＋…＋Ｌβ）での減速速度ＶB （＝ＶＢαβ）は基準許容進入速度ＶＰβに対して、
ＶＢαβ＝（ＶＰβ² ＋２・（０．８・ＸgLim）・（Ｌ（α＋１）＋…＋Ｌβ−ｌr））^1/2 …（２２）
さらに、上記減速速度演算・出力部４３では、上記距離Ｌ1 、許容減速度ＸgLimにより、上記各減速速度ＶＢ１β（ＶＢ１（n+1 ）〜Ｖp1）をそれぞれ現在位置点Ｐ０における減速速度に変換して推定減速速度ＶＢＰとして演算し、この推定減速速度ＶＢＰと車速Ｖとをそれぞれ比較して車速Ｖが推定減速速度ＶＢＰ以上の際に減速制御を行うべく信号を上記許容減速度ＸgLimに応じて、上記各制御装置３２〜３４に所定に出力するようになっている。また、減速制御の実行は、上記制御実行判断部４２からの信号により解除、あるいは警報制御への変更が可能になっている。尚、減速制御の際に上記警報装置３５からその旨警報（ランプの点灯、音声の発生等）させるように信号を出力する。
【０１２５】
ここで、上記推定減速速度ＶＢＰは、以下のように算出される。
上記（２２）式より、先行点Ｐβに対する到着点Ｐ０（点Ｐβ〜点Ｐ０＝Ｌ1 ＋Ｌ2 ＋…＋Ｌβ）での減速速度ＶB （＝ＶＢ０β＝ＶＢＰ）は基準許容進入速度ＶＰβに対して、
ＶＢＰ＝（ＶＰβ² ＋２・（０．８・ＸgLim）・（Ｌ1 ＋Ｌ2 ＋…＋Ｌβ−ｌr））^1/2
また、先行点Ｐβに対する到着点Ｐ１（点Ｐβ〜点Ｐ１＝Ｌ2 ＋…＋Ｌβ）での警報速度ＶB （＝ＶＢ１β）は基準許容進入速度ＶＰβに対して、
ＶＢ１β＝（ＶＰβ² ＋２・（０．８・ＸgLim）・（Ｌ2 ＋…＋Ｌβ−ｌr））^1/2
従って、これら２つの式から、
ＶＢＰ＝（ＶＢ１β² ＋２・（０．８・ＸgLim）・Ｌ1 −ｌr）^1/2 …（２３）
また、上記減速制御は、上記許容減速度ＸgLimに応じて、上記エンジン制御装置３３に対して過給圧ダウン＋燃料カットの実行、あるいは、上記エンジン制御装置３３に対して過給圧ダウン＋燃料カット＋スロットル開度閉制御の実行、あるいは、上記エンジン制御装置３３に対する過給圧ダウン＋燃料カット＋スロットル開度全閉の実行＋上記トランスミッション制御装置３２に対するシフトダウンの実行、あるいは、上記エンジン制御装置３３に対する過給圧ダウン＋燃料カット＋スロットル開度全閉の実行＋上記トランスミッション制御装置３２に対するシフトダウンの実行＋上記ブレーキ制御装置３４に対するブレーキ作動、ブレーキ力増加の実行のいずれかを選択して行わせるようになっている。
【０１２６】
次に、本発明の第３の実施の形態による車両運動制御開始制御を図１３のフローチャートで説明する。このプログラムは、例えば、所定時間毎に実行され、プログラムがスタートすると、ステップＳ３０１で、車速センサ３，ハンドル角センサ４，ヨーレートセンサ５，前後加速度センサ６，ターンシグナルスイッチ３１から、車速Ｖ，ハンドル角θH，ヨーレートγ，前後加速度，動作信号の各信号を読込むとともに、ナビゲーション装置７から点データ及び道路種別情報，道路形状検出装置８から道路幅データを読込み、Ｓ３０２に進む。
【０１２７】
上記Ｓ３０２では、車両諸元算出部１１ａで、車速Ｖ，ハンドル角θH，ヨーレートγを基にコーナリングパワＫf，Ｋrを推定し、このコーナリングパワＫf，Ｋrを用いて路面摩擦係数推定値μを算出し、Ｓ３０３に進む。
【０１２８】
上記Ｓ３０３では、ヨーレート応答時間基準値算出部１１ｂで、上記車速Ｖ，上記路面摩擦係数推定値μを基に前記（１）式によりヨーレート応答時間ｔrを算出し、Ｓ３０４に進む。
【０１２９】
上記Ｓ３０４では、カーブ形状検出部１２で、上記ナビゲーション装置７からの点データ及び道路種別情報と上記道路形状検出装置８からの道路幅データとを基に走行路前方のカーブを検出し、この検出した前方カーブの入口までの距離ｌcを算出して、Ｓ３０５に進む。
【０１３０】
上記Ｓ３０５では、許容横加速度算出部３６で、上記車速Ｖ，上記路面摩擦係数推定値μ，前方カーブのカーブ角度とカーブ方向を基に許容横加速度ａylnを算出し、Ｓ３０６に進む。
【０１３１】
上記Ｓ３０６では、制御開始判定・制御部３８で、以下に説明するサブルーチンによって、トランスミッション制御装置３２、エンジン制御装置３３、ブレーキ制御装置３４、警報装置３５の制御開始判定を行い、上記各制御装置３２〜３５による必要な制御を実行した後、ルーチンを抜ける。
【０１３２】
次に、上記制御開始判定・制御部３８によって行われる制御開始判定のサブルーチンがスタートすると、Ｓ３１１では、ヨーレート応答距離算出部３７で、上記車速Ｖ，上記ヨーレート応答時間ｔrとを基に前記（１４）式でヨーレート応答距離ｌrを算出し、Ｓ３１２に進む。
【０１３３】
上記Ｓ３１２では、基準許容進入速度設定部４０で、カーブの曲率半径Ｒnと上記許容横加速度ａylnを基に基準許容進入速度Ｖpnを設定して、Ｓ３１３に進む。
【０１３４】
上記Ｓ３１３では、許容減速度設定部４１で、路面摩擦係数推定値μと道路勾配ＳＬの道路状況に応じて許容減速度ＸgLimを設定し、Ｓ３１４に進む。
【０１３５】
上記Ｓ３１４に進むと、ターンシグナルスイッチ３１が作動されているか否か判定し、上記ターンシグナルスイッチ３１が作動されている場合はＳ３１５に進み減速制御を解除（ＯＦＦ）て、Ｓ３１６に進み、警報制御を解除（ＯＦＦ）してルーチンを抜ける。
【０１３６】
一方、上記Ｓ３１４で上記ターンシグナルスイッチ７が作動されていないと判定するとＳ３１７へ進み、ハンドル角センサ４からの信号により運転者による操舵量が予め設定しておいた値以上か否かを判定する。そして、運転者による操舵量が設定値以上の場合は、上記Ｓ３１５に進み減速制御を解除（ＯＦＦ）し、Ｓ３１６に進み警報制御を解除（ＯＦＦ）してルーチンを抜ける。
【０１３７】
上記Ｓ３１７での判定により、操舵量が設定値より小さい場合（上記ターンシグナルスイッチ３１がＯＦＦかつ操舵量が小さい場合）は、Ｓ３１８に進み、減速速度演算・出力部４３で点Ｐ１における各データ（各減速速度ＶＢ１β（ＶＢ１（n+1 ）〜Ｖp1））を基に現在位置点Ｐ０での減速速度を推定し演算する（推定減速速度ＶＢＰ）。このとき、上記各推定減速速度の演算は、上記ヨーレート応答距離ｌrを考慮して行われる。
【０１３８】
そして、Ｓ３１９に進み、車速Ｖと上記各推定減速速度ＶＢＰとを比較し、車速Ｖが上記各推定減速速度ＶＢＰのいずれか一つ以上になっていれば（Ｖ≧ＶＢＰ）、Ｓ３２０へと進む。
【０１３９】
上記Ｓ３２０では、車速Ｖを基に、運転者が減速判定での減速度（０．８・ＸgLim）以上の減速を既に行っているか否かの判定を行う。そして運転者が減速判定での減速度以上の減速を行っていないならば減速の必要が有ると判定してＳ３２１へ進み減速制御を実行（ＯＮ）してルーチンを抜ける。
【０１４０】
また、上記Ｓ３２０で、運転者が減速判定での減速度（０．８・ＸgLim）以上の減速を既に行っている場合は、運転者は既に対処中であり、強制減速をする必要がないと判定し、Ｓ３２２へ進み減速制御を解除（ＯＦＦ）し、さらにＳ３２３に進んで警報制御を実行（ＯＮ）して（すなわち減速制御から警報制御に変更して）ルーチンを抜ける。
【０１４１】
一方、上記Ｓ３１９での車速Ｖと上記各推定減速速度ＶＢＰとの比較の結果、車速Ｖが全ての推定減速速度ＶＢＰより小さくなっている場合にはＳ３２４に進み減速制御を解除（ＯＦＦ）し、Ｓ３２５に進んで警報速度演算・出力部４４で点Ｐ１における各データ（各警報速度ＶＡ１β（ＶＡ１（n+1 ）〜Ｖp1））を基に現在位置点Ｐ０での警報速度を推定し演算する（推定警報速度ＶＡＰ）。このとき、上記各推定警報速度の演算は、上記推定減速速度の演算と同様に、上記ヨーレート応答距離ｌrを考慮して行われる。
【０１４２】
そして、Ｓ３２６に進み、車速Ｖと上記各推定警報速度ＶＡＰとを比較し、車速Ｖが上記各推定警報速度ＶＡＰのいずれか一つ以上になっていれば（Ｖ≧ＶＡＰ）、Ｓ３２７へと進む。
【０１４３】
上記Ｓ３２７では、車速Ｖを基に運転者が警報判定での減速度（０．５・ＸgLim）以上の減速を既に行っているか否かの判定を行う。そして運転者が警報判定での減速度以上の減速を行っていないならば警報の必要が有ると判定して上記Ｓ３２３へ進み警報制御を実行（ＯＮ）してルーチンを抜ける。
【０１４４】
また、上記Ｓ３２７で、運転者が警報判定での減速度（０．５・ＸgLim）以上の減速を既に行っている場合は、運転者は既に対処中であり、警報をする必要がないと判定し、Ｓ３２８へ進み警報制御を解除（ＯＦＦ）してルーチンを抜ける。
【０１４５】
ここで、上記Ｓ３２３の警報制御実行（ＯＮ）は、前述したように、チャイム・ブザー、音声警報発生、警告灯等、あるいは、これらの組み合わせにより構成された警報装置３５により行われ、上記Ｓ３２７を経て行われる警報制御では、例えば、「カーブのため減速して下さい。」等の音声警報、あるいはチャイム・ブザー音のみの警報を行い、上記Ｓ３２２を経て行われる警報制御では、例えば、チャイム・ブザー音のみの警報を行う。
【０１４６】
また、上記Ｓ３２１の減速制御実行（ＯＮ）の際には、上記警報装置３５により「カーブのため減速します。」等の音声警報とブザーと警告灯の点灯が行なわれる。ここで、上記減速速度演算・出力部４３で実行される減速制御は、上記許容減速度ＸgLimに応じて、上記エンジン制御装置３３に対して過給圧ダウン＋燃料カットの実行、あるいは、上記エンジン制御装置３３に対して過給圧ダウン＋燃料カット＋スロットル開度閉制御の実行、あるいは、上記エンジン制御装置３３に対する過給圧ダウン＋燃料カット＋スロットル開度全閉の実行＋上記トランスミッション制御装置３２に対するシフトダウンの実行、あるいは、上記エンジン制御装置３３に対する過給圧ダウン＋燃料カット＋スロットル開度全閉の実行＋上記トランスミッション制御装置３２に対するシフトダウンの実行＋上記ブレーキ制御装置３４に対するブレーキ作動、ブレーキ力増加の実行のいずれかが選択して行われる。
【０１４７】
尚、上記Ｓ３１２、Ｓ３１７、Ｓ３２０、Ｓ３２７の各判定処理は制御実行判断部３１により行われるものである。
【０１４８】
このように、本実施の形態においても、上述の本発明の第１，２の実施の形態と同様に、前方カーブに対する車両運動制御は、車両のヨーレート応答（ヨーレート応答距離）を考慮した適切なタイミングで行うことができ、高いレベルでの安全維持を実現することがきる。
【０１４９】
【発明の効果】
以上、説明したように本発明によれば、車両の走行状態からヨーレート応答時間を算出し、このヨーレート応答時間を基に前方カーブに対する車両の運動制御の開始タイミングを判定するので、上記前方カーブ走行時に予測される将来の挙動に対し車両の挙動遅れを考慮した適切なタイミングで運動制御を開始することができ、高いレベルでの安定性向上を実現することができる。また、車両の走行状態からヨーレート応答時間を算出し、このヨーレート応答時間を基にヨーレート応答距離を算出し、このヨーレート応答距離を車両の運動制御に反映させることで車両の挙動遅れを考慮した適切なタイミングで運動制御を開始することができ、高いレベルでの安定性向上を実現することができる。
【図面の簡単な説明】
【図１】図１〜７は、本発明の第１の実施の形態を示し、図１は、車両運動制御装置の全体構成を示すブロック図
【図２】カーブ形状検出部の構成の説明図
【図３】カーブの曲率半径の求め方の説明図
【図４】求めたカーブの曲率半径の補正の説明図
【図５】実際にナビゲーション装置から得られる点データの例の説明図
【図６】データ整理部での各ケースの説明図
【図７】車両運動開始判定制御のフローチャート
【図８】図８〜９は、本発明の第２の実施の形態を示し、図８は、車両運動制御装置の全体構成を示すブロック図
【図９】ヨーレート応答時間補正係数と必要ヨーレートの特性の説明図
【図１０】前方カーブに対する車両運動開始判定制御のフローチャート
【図１１】図１１〜１４は本発明の第３の実施の形態を示し、図１１は、車両運動制御装置の全体構成を示すブロック図
【図１２】制御開始判定・制御部の説明図
【図１３】車両運動開始判定制御のフローチャート
【図１４】制御開始判定のサブルーチンのフローチャート
【符号の説明】
９ … 制動力制御装置
１０ … 警報装置
１１ … ヨーレート応答時間演算部（ヨーレート応答時間演算手段）
１２ … カーブ形状検出部（カーブ形状検出手段）
１３ … 制御開始判定・制御部（制御開始判定・制御手段）
１４ … 必要ヨーレート演算部（必要ヨーレート演算手段）[0001]
[Field of the Invention]
The present invention relates to a vehicle motion control apparatus capable of performing vehicle motion control at an appropriate timing.
[0002]
[Prior art]
In recent years, the vehicle behavior is detected based on the driving environment and the driving state of the vehicle, and control such as braking force control and steering control is performed on the detected vehicle behavior, or a warning is issued to the driver to perform a predetermined brake operation or Various technologies have been developed for vehicle motion control devices that maintain safety during vehicle travel by encouraging vehicle behavior control such as steering of a steering wheel.
[0003]
For example, in Japanese Patent Laid-Open No. 2-70561, a target yaw rate is compared with an actual yaw rate (actual yaw rate) to determine whether the motion state of the vehicle is an understeer tendency or an oversteer tendency with respect to the target yaw rate. In this case, a technique is disclosed in which the braking force is applied to the inner wheel for correction, and in the case of an oversteer tendency, the braking force is applied to the outer wheel for correction to improve stability during curve driving.
[0004]
[Problems to be solved by the invention]
However, since the control according to the above prior art is a control that detects the current vehicle behavior based on the actual yaw rate, the steering wheel angle, etc., and performs the detected current vehicle behavior, Vehicle behavior cannot be controlled, and there are limits to improving safety.
[0005]
On the other hand, future vehicle behavior on a forward curve is detected by obtaining road information ahead of the road based on navigation information, image information, etc., and an alarm is given to the detected vehicle behavior on the forward curve, etc. Technology is being developed to improve the stability during running by giving off or controlling the braking force. However, in this technology, for example, response time due to a delay in the response of the vehicle depending on the road surface condition is not considered, so it is difficult to control the motion of the vehicle at an appropriate timing. There is a limit.
[0006]
The present invention has been made in view of the above circumstances, and an object of the present invention is to provide a vehicle motion control device capable of starting motion control at an appropriate timing for future vehicle behavior during forward curve traveling. To do.
[0007]
[Means for Solving the Problems]
In order to achieve the above object, a vehicle motion control device according to the present invention according to claim 1 detects a traveling state of a vehicle and performs at least one of vehicle behavior control and alarm control according to the detected traveling state. In the vehicle motion control device that controls the motion of the vehicle, the road surface friction coefficient estimated value is calculated based on the running state, and the vehicle yaw rate responds when the vehicle is steered based on the road surface friction coefficient estimated value and the vehicle speed. The yaw rate response time calculating means for calculating the time to the curve, the curve shape detecting means for detecting the curve ahead of the road and calculating the distance from the vehicle to the front curve, and the yaw rate calculated by the yaw rate response time calculating means. Determine and control the start of vehicle motion control for the forward curve based on the response time and the distance to the forward curve calculated by the curve shape detection means Characterized in that a control start determination and control unit.
[0008]
That is, the vehicle motion control apparatus according to the present invention described in claim 1 calculates the road surface friction coefficient estimated value based on the running state by the yaw rate response time calculating means, and determines the vehicle based on the road surface friction coefficient estimated value and the vehicle speed. The time until the yaw rate of the vehicle responds when steered is calculated, the curve shape detection means detects the curve ahead of the road, calculates the distance from the vehicle to the front curve, and the control start determination / control The start of vehicle motion control with respect to the forward curve is determined and controlled based on the time until the yaw rate responds by means and the distance to the forward curve.
[0009]
According to a second aspect of the present invention, there is provided the vehicle motion control apparatus according to the first aspect, wherein the allowable lateral acceleration when traveling on the front curve is determined based on the traveling state and the road surface state of the vehicle. Calculate necessary yaw rate calculating means for calculating the yaw rate of the vehicle required for traveling on the forward curve based on the allowable lateral acceleration and the curvature radius of the forward curve detected by the curve shape detecting means. The yaw rate response time calculation means sets the yaw rate response time as a value obtained by correcting the yaw rate response time calculated based on the estimated road friction coefficient and the vehicle speed according to the required yaw rate.
[0010]
According to a third aspect of the present invention, there is provided the vehicle motion control apparatus according to any one of the first and second aspects, wherein the control start determination / control means is a vehicle speed and curve shape detection. Based on the distance to the forward curve of the vehicle calculated by the means, the time until the vehicle reaches the forward curve is calculated, and the arrival time to the forward curve and the yaw rate response calculated by the yaw rate response time calculating means The start of vehicle motion control is determined by comparing the time.
[0011]
  According to a fourth aspect of the present invention, there is provided the vehicle motion control apparatus according to any one of the first and second aspects, wherein the control start determination / control means includes a vehicle speed and a yaw rate response time. Based on the yaw rate response time of the vehicle calculated by the calculation means,Yaw rateCalculate the response distanceYaw rateThe start of vehicle motion control is determined by comparing the response distance with the distance to the forward curve of the vehicle calculated by the curve calculating means.
[0012]
According to a fifth aspect of the present invention, there is provided the vehicle motion control apparatus according to any one of the first and second aspects, wherein the control start determination / control means includes a vehicle speed and a yaw rate response time. Based on the yaw rate response time of the vehicle calculated by the calculation means, the yaw rate response distance when the vehicle is controlled for motion is calculated, and the start of vehicle motion control is determined based on the yaw rate response distance.
[0013]
According to a sixth aspect of the present invention, there is provided a vehicle movement control device according to the present invention, wherein the vehicle movement control device according to any one of the first, second, third, fourth, and fifth aspects is configured to determine a vehicle running state and a road surface state. Based on this allowable lateral acceleration and the radius of curvature of the forward curve detected by the curve shape detection means, it is necessary to calculate the necessary yaw rate of the vehicle on the forward curve based on the above curve. In the case of braking control that includes a yaw rate calculation means and the vehicle behavior control independently applies a braking force to a wheel selected based on a target yaw rate obtained based on the running state of the vehicle, the required yaw rate is determined as the braking force. It is set as the target yaw rate when performing control.
[0014]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, embodiments of the present invention will be described with reference to the drawings.
1 to 7 show a first embodiment of the present invention, FIG. 1 is a block diagram showing the overall configuration of a vehicle motion control device, FIG. 2 is an explanatory diagram of the configuration of a curve shape detection unit, and FIG. FIG. 4 is an explanatory diagram of how to determine the curve curvature radius, FIG. 4 is an explanatory diagram of correction of the calculated curvature radius of the curve, FIG. 5 is an explanatory diagram of an example of point data actually obtained from the navigation device, and FIG. FIG. 7 is an explanatory diagram of each case in the data organizing unit, and FIG. 7 is a flowchart of vehicle motion control start determination for the forward curve.
[0015]
In FIG. 1, reference numeral 1 denotes an overall configuration of a vehicle motion control device mounted on a vehicle. A control unit 2 of the vehicle motion control device 1 includes a vehicle speed sensor 3, a handle angle sensor 4, a yaw rate sensor 5, a longitudinal acceleration. The vehicle speed V, the steering wheel angle θH, the yaw rate γ, and the longitudinal acceleration signals detected by each sensor of the sensor 6 are input.
[0016]
Further, a navigation device 7 is connected to the control unit 2, and point data indicating roads in map information and road type information such as highways, general national roads, and local roads are input from the navigation device 7. ing. Here, for example, the navigation device 7 is a GPS receiver for receiving a radio wave from GPS hygiene by a global health system (GPS) and measuring its own position, a road including road information, terrain information, and the like. In the present embodiment, in particular, the control unit 2 has its own (own vehicle) position, and the CD-ROM device has a road map. The road data point data and road type information stored as information are output as necessary.
[0017]
Furthermore, a road shape detection device 8 is connected to the control unit 2, and data relating to the shape of the road such as the road width is input. In the present embodiment, the road shape detection device 8 is provided so as to detect the road width in particular. For example, a pair of CCD cameras take a stereo image of an object outside the vehicle from different viewpoints. A three-dimensional distance image is generated by processing the distance information over the entire image based on the principle of triangulation from the corresponding positional deviation amount for a pair of stereo images, and a histogram of the distance distribution of this three-dimensional distance image By processing, the road is recognized and the road width is calculated.
[0018]
The control unit 2 determines the vehicle motion control start timing with respect to the curve ahead of the travel path based on the inputs from the sensors 3, 4, 5, 6, the navigation device 7, and the road shape detection unit 8. When a running vehicle has reached the motion control start timing, at least one of the braking force control device 9 and the alarm device 10 is a predetermined signal for starting vehicle motion control with respect to the forward curve (hereinafter, referred to as the following control signal). , Referred to as a control start signal). Here, in the present embodiment, the braking force control device 9 is an example of a vehicle behavior control device that detects a vehicle behavior based on a vehicle running state and performs predetermined control on the vehicle behavior. The target yaw rate is calculated for the vehicle behavior, and the brake control is performed according to the target yaw rate.
[0019]
The control device 2 mainly includes a yaw rate response time calculation unit 11, a curve shape detection unit 12, a control start determination / control unit 13, and a necessary yaw rate calculation unit 14.
[0020]
The yaw rate response time calculation unit 11 is formed as a yaw rate response time calculation unit, and mainly includes a vehicle specification calculation unit 11a and a yaw rate response time calculation unit 11b.
[0021]
For example, the vehicle specification calculation unit 11a is configured by the applicant of the present invention in accordance with the method disclosed in Japanese Patent Application Laid-Open No. 8-2274, the vehicle speed V from the vehicle speed sensor 3, the handle angle θH from the handle angle sensor 4, and the yaw rate sensor. Based on the yaw rate γ from 5, the motion equation of the translational movement in the lateral direction of the vehicle is established to estimate the cornering powers Kf and Kr of the front and rear wheels, and the road surface friction coefficient estimated value μ is estimated based on these cornering powers. It has become.
[0022]
The yaw rate response time calculation unit 11b receives the vehicle speed V from the vehicle speed sensor 3 and the road surface friction coefficient estimated value μ from the vehicle specification calculation unit 11a. tr is calculated.
[0023]
Here, the yaw rate response time tr is a time until the yaw rate of the vehicle responds to the steering of the steering wheel when the driver steers, and the yaw rate response time tr is the yaw rate response time calculation unit 11b. In
tr = (m · Lf · V) / (2 · L · Kr · μ) (1)
Is calculated by In the equation, m is the vehicle mass, Lf is the distance between the front shaft and the center of gravity, and L is the wheelbase.
[0024]
For example, as shown in FIG. 2, the curve shape detection unit 12 includes a three-point detection unit 12a, a Pn-1 Pn distance calculation unit 12b, a Pn Pn + 1 distance calculation unit 12c, a long / short determination unit 12d, and a midpoint calculation unit 12e. The center point equidistant point calculation unit 12f, the radius of curvature calculation unit 12g, the organizing unit 12h, the data organizing unit 12i, and the curve distance calculating unit 12j are mainly configured.
[0025]
As shown in FIG. 5, the three-point detection unit 12a is configured to detect three points on the road selected by the driving direction of the vehicle or the driver from the road point data input from the navigation device 7, as shown in FIG. The first point Pn-1, the second point Pn, and the third point Pn + 1 are sequentially read at intervals (from the side closer to the vehicle). From these three points read, the positional information of the first point Pn-1 and the second point Pn is output to the Pn-1 Pn distance calculation unit 12b, and the second point Pn and the third point Pn are output. The position information of the point Pn + 1 is output to the PnPn + 1 distance calculator 12c. Let Pn-1 = (Xn-1, Yn-1), Pn = (Xn, Yn), Pn + 1 = (Xn + 1, Yn + 1). The representative point of the curve is Pn. Therefore, the curve of the point P1 is calculated from the points P0, P1, P2, the curve of the point P2 is calculated from the points P1, P2, P3,..., And the curve of the point Pn is calculated from the points Pn-1, Pn, Pn + 1. Is done.
[0026]
The Pn-1 Pn distance calculation unit 12b is configured to output the first point Pn-1 based on the positional information of the first point Pn-1 and the second point Pn input from the three-point detection unit 12a. And the second point Pn are calculated and output to the long / short determination unit 12d and the correction unit 12h.
[0027]
The Pn Pn + 1 distance calculation unit 12c is based on the position information of the second point Pn and the third point Pn + 1 input from the three-point detection unit 12a, and the second point Pn and the above-described point. A linear distance connecting the third point Pn + 1 is calculated and output to the long / short determining unit 12d and the correcting unit 12h.
[0028]
The long / short determination unit 12d is configured such that the linear distance connecting the first point Pn-1 and the second point Pn input from the Pn-1 Pn distance calculation unit 12b and the Pn Pn + 1 distance calculation unit 12c. The straight line distance connecting the second point Pn and the third point Pn + 1 inputted from is compared with each other to determine the length of the straight line distance. Then, each data (position, distance) with a shorter straight line distance is output to the midpoint calculation unit 12e and the correction unit 12g, and each data (position, distance) with a longer straight line distance is output to the midpoint. It outputs to the same distance point calculation part 12f.
[0029]
As a result of the comparison by the long / short determination unit 12d, if both straight line distances are determined to be the same length, either straight line may be used, so the first point Pn-1 and the second point A straight line connecting the points Pn is set in advance so as to be treated as a short straight line (a straight line connecting the second point Pn and the third point Pn + 1 may be treated as a short straight line).
[0030]
The midpoint calculating unit 12e calculates a half of the shorter straight line distance based on each straight line data (position, distance) input from the long / short determining unit 12d, and calculates the shorter distance. It is formed so as to determine the midpoint position on the straight line. Here, a straight line connecting the first point Pn-1 and the second point Pn is a short straight line, and a midpoint is Pn-1, n = (Xn-1, n, Yn-1, n). ,

Each data calculated by the midpoint calculation unit 12e is output to the midpoint same distance point calculation unit 12f and the curvature radius calculation unit 12g.
[0031]
The midpoint / distance point calculation unit 12f is configured to calculate each of the data (position and distance) of a straight line having a long distance input from the long / short determination unit 12d and the shorter straight line distance input from the midpoint calculation unit 12e. From the half-distance data, the midpoint equidistant point is determined on the long straight line from the second point to a half distance of the short straight line distance. Here, the straight line connecting the second point Pn and the third point Pn + 1 is a long straight line, and the midpoint equidistant point is Pn, n + 1 = (Xn, n + 1, Yn, n + 1). )

The position data of the midpoint equidistant point Pn, n + 1 computed by the midpoint equidistant point computation unit 12f is output to the curvature radius computation unit 12g.
[0032]
The radius-of-curvature calculation unit 12g has the midpoint same distance point Pn, n + calculated by the midpoint same distance point calculation unit 12f and the position data of the middle point Pn-1, n input from the middle point calculation unit 12e. Based on the position data of 1, as shown in FIG. 3, the straight line perpendicular to the shorter straight line (here, Pn-1 Pn) at the midpoint Pn-1, n and the midpoint equidistant point Pn, n + The intersection point of the straight line perpendicular to the longer straight line (here, Pn Pn + 1) is determined as the center position On of the curve of the road, and the curvature radius Rn of the road is determined based on the curve center position On. It is formed to calculate. The result calculated by the curvature radius calculation unit 12g is output to the correction unit 12h.
[0033]
That is,

When M is deleted from the above equations (4) and (5) to obtain N,

And the curve center position On is

It becomes.
[0034]
Accordingly, the curvature radius Rn is obtained by the following equation.
[0035]

・ ((Xon-Xn-1, n)²+ (Yon-Yn-1, n)²)^1/2    (8)
Here, when the radius of curvature Rn is positive, it turns left, and when it is negative, it turns right.
[0036]
Further, a distance Lon from the curve center position On to the second point Pn, which is a representative point of the curve, is obtained by the following equation (9).
[0037]
Lon = ((Xon-Xn)²+ (Yon-Yn)²)^1/2      ... (9)
The correction unit 12h calculates a difference Deln between the curvature radius Rn from the curvature radius calculation unit 12g and the distance Lon from the curve center position On to the second point Pn, and this difference Deln is an error setting described later. When the value exceeds the value, the radius of curvature Rn is corrected to make the difference Deln the error set value.
[0038]
The final curve information (the position (Xn, Yn), point of the representative point Pn of the curve), the point corrected by the correcting unit 12h or for each point where the difference Deln is not more than the error set value and has not been corrected. The distance Ln between the point Pn-1 and the point Pn, the final radius of curvature Rn, the curve center position On, the curve angle θn of each point obtained from the angle formed by the straight line Pn-1 Pn and the straight line Pn Pn + 1, the curve start point Lsn (the point between the curve center position On and the point perpendicular to the straight line Pn-1 Pn) and the point Pn-1, the distance Lssn from the vehicle position to the representative point of each curve) is stored, and the data organizing unit 12i Is output.
[0039]
The error setting value is varied according to both the road width D and the shorter linear distance, and is set to (error setting value) = α · D (α is the shorter linear distance) A constant set accordingly: hereinafter referred to as a point interval correction coefficient).
[0040]
As the road width D, the value of the road width obtained from the road shape detection device 8 is normally adopted. However, when data cannot be obtained from the road shape detection device 8, the navigation is performed. The road width D is set based on road type information such as a highway, a general national road, and a local road obtained from the device 7. Here, as the road width D increases, the error setting value increases and the correction is not performed. This represents that the radius of curvature Rn increases as the road width increases on an actual road. is there.
[0041]
The point interval correction coefficient α is in a direction in which correction is not performed because the shorter the linear distance, the larger the point interval correction coefficient α and the larger the error setting value. For example, α = 1.2 when the shorter straight line distance is 20 m or less, α = 0.6 when medium distance is 100 m or less, and α = 0.3 when larger than 100 m. This is because the fact that the straight line distance is short means that the point data is set finely and it can be considered that the road is correctly expressed, so that correction is not performed.
[0042]
Detailed correction by the correction unit 12h is shown in FIG. The vector from Pn-1 to Pn is B1 = (Xn-Xn-1, Yn-Yn-1) = (Xb1, Yb1), and the vector from P2 to P3 is B2 = (Xn + 1-Xn, Yn + 1). -Yn) = (Xb2, Yb2).
[0043]
The angle θn formed by B1 and B2 is
cos θn = (Xb1 · Xb2 + Yb1 · Yb2) / (| B1 | · | B2 |)
The error (ratio) Pdeln between Lon and Rn is

Therefore, the difference Deln between Lon and Rn is as follows.
[0044]

Here, when the difference Deln exceeds the error set value (α · D), correction is performed so that Deln = α · D with respect to the curvature radius Rn.
That is,

Since the curve information is obtained by the curve shape detection unit 12 as described above, the point data from the navigation device 7 that is not a constant interval can be used as it is, and the data for calculation is complemented or a particularly complicated calculation is performed. Therefore, the radius of curvature of the travel path can be obtained quickly and accurately with simple arithmetic processing.
[0045]
Further, the connection between the curve detection points for obtaining the curvature radius is natural, and a value that accurately represents the actual road shape can be obtained.
[0046]
Further, the calculation error is generated to be smaller than the radius of curvature of the actual curve, which is preferable for issuing an appropriate alarm in the alarm / deceleration control at the time of entering the curve, for example.
[0047]
Further, by providing the curvature radius correction unit 12h, more accurate calculation of the curvature radius becomes possible, and by changing the error setting value used as a reference for correction according to the actual road shape and the number of point data, More accurate calculation can be performed. That is, in order to express that the radius of curvature increases as the road width increases on an actual road, the error setting value increases as the road width increases, and the correction is not performed. In addition, since the straight line distance is short, it can be considered that the point data is set finely and expresses the road correctly.Therefore, the shorter the straight line distance is, the larger the error setting value becomes and the correction is not performed. Become.
[0048]
The data organizing unit 12i organizes data for each point detected by the curve shape detecting unit 12, and predetermined data of the arranged data is sent to the curve distance calculating unit 12j and the necessary yaw rate calculating unit 14. Since the calculation is performed after reading, unnecessary calculations are reduced.
[0049]
That is, the point data from the navigation device 7 may represent one curve with several points, and even if they are separate curves, if one curve is controlled, the other curve is obtained. In some cases, control can be omitted.
[0050]
Therefore, in consideration of the above, the data organizing unit 12i applies the following four cases for each point data from the point Pn-1 to the point Pn, and arranges the data into necessary point data. ing.
[0051]
Case 1: The curve is tight, but there is a margin in the deceleration distance (= Rn-1 -Rn) from point Pn-1 to point Pn (Fig. 6 (a))
If | Rn-1 |> | Rn |, Rn-1 · Rn> 0 and Ln> | Rn-1 |-| Rn |, the curve information of the points Pn-1 and Pn is required. That is, since there is a margin for deceleration from the point Pn-1 to the point Pn, independent control is required for each of the points Pn-1 and Pn.
[0052]
Considering that the points Pn-1 and Pn represent one curve, the curve angle θn at the point Pn is added to obtain one curve angle (curve total angle θsn).

・ Case 2 ... When the curve becomes tight and there is no margin in the deceleration distance (= Rn-1 -Rn) from point Pn-1 to point Pn (Fig. 6 (b))
If | Rn-1 |> | Rn |, Rn-1 · Rn> 0 and Ln <| Rn-1 |-| Rn |, the curve information at the point Pn-1 is ignored (reduced). That is, by controlling the curve of the point Pn, the control of the curve of the point Pn-1 is absorbed, and the curve information of the point Pn-1 is wasted and ignored (reduced).
[0053]
Considering that the points Pn-1 and Pn represent one curve, the curve angle θn at the point Pn is added to obtain one curve angle (curve total angle θsn).

・ Case 3 ... When the curve becomes loose (Fig. 6 (c))
| Rn-1 | <| Rn |, Rn-1 · Rn> 0
Then, the curve information of the point Pn is ignored (reduced). That is, since the speed is decelerated at the point Pn-1, the curve information of the point Pn, which is a gentler curve than the point Pn-1, becomes unnecessary and is ignored (reduced). When Ln is long, if the vehicle accelerates sufficiently (if it can be regarded as an independent curve of point Pn-1 and point Pn), the vehicle speed may increase before reaching point Pn. The curve information of the point Pn may be held according to the size of Ln.
[0054]
Considering that the points Pn-1 and Pn represent one curve, the curve angle θn at the point Pn is added to obtain one curve angle (curve total angle θsn).

If the point Pn-1 and the point Pn can be regarded as independent curves, the curve angle θn at the point Pn is not added, but a new addition is started (determined according to the size of Ln).
[0055]
・ Case 4 ... When the turning direction of the curve is switched (Fig. 6 (d))
Rn-1 · Rn <0
Then, the curve information of the point Pn is necessary. That is, when going from the point Pn-1 to the point Pn, since the turning direction is different, the data is not organized here.
[0056]
Further, the total of the curve angles that have continued to the point Pn-1 is defined as the total curve angle θs (n-1) to the point Pn-1.
[0057]
Further, addition is started in order to obtain the total curve angle θsn from the point Pn.
All angle of curve up to point Pn θsn = 2 ・ cos^-1(Rn / Lon)
In addition, when it applies to each said case and the case where it is required and the case where it is not required overlaps with respect to one point, that point is disregarded (reduction).
[0058]
Here, the reason why the deceleration distance is calculated by the difference between the curvature radii Rn and Rn-1 of the curve is as follows. The reference allowable approach speed at point Pn is Vpn, the deceleration is a, and the allowable lateral acceleration is ayln.

When the deceleration a is 50% of the allowable lateral acceleration ayl (1/2) · ayl,
Deceleration distance = Rn-1 -Rn
From this result, the deceleration distance is calculated by the difference between the curvature radii Rn and Rn-1.
[0059]
The curve distance calculation unit 12j receives the data from the data organizing unit 12i and the own (own vehicle) position data from the navigation device 7, and calculates the distance lc from the entrance of the curve ahead of the traveling road to the own vehicle. It is like that.
[0060]
The control start determination / control unit 13 is formed as control start determination / control means, and is detected by the vehicle speed V, the yaw rate response time tr calculated by the yaw rate response time calculation unit 11, and the curve detection unit 12. The data indicating the distance lc from the vehicle to the front curve entrance is input, and based on the vehicle speed V and the distance lc to the curve entrance, the time tc until the vehicle reaches the front curve is calculated. By comparing the arrival time tc to the curve entrance and the yaw rate response time tr, the timing for starting the motion control for the forward curve is determined, and at the motion control start timing, the braking force control device 9 or the alarm The control start signal is output to at least one of the devices 10.
[0061]
That is, the control start determination / control unit 13 determines the arrival time tc to the curve entrance as follows:
Arrival time tc = (distance lc to curve entrance) / (vehicle speed V) (13)
When the arrival time tc to the calculated curve is equal to or less than the yaw rate response time tr, the motion control start timing for the forward curve is set as at least one of the braking force control device 9 and the alarm device 10. On the other hand, the control start signal is output.
[0062]
Here, in the control start determination / control unit 13, the yaw rate response distance lr (the distance traveled by the vehicle before the yaw rate responds to the steering of the driver) based on the vehicle speed V and the yaw rate response time tr. The motion control start timing for the forward curve may be determined by comparing the yaw rate response distance lr and the distance lc to the curve. In this case, the yaw rate response distance lr is
Yaw rate response distance lr = (vehicle speed V) · (yaw rate response time tr) (14)
The motion control start timing is when the yaw rate response distance lr is equal to or greater than the distance lc to the corner entrance.
[0063]
Thus, by determining the motion control start timing for the forward curve based on the yaw rate response time tr, the motion control for the forward curve is set to an appropriate timing considering the vehicle responsiveness to the motion control. Can do.
[0064]
The required yaw rate calculator 14 is mainly composed of an allowable lateral acceleration calculator 14a and a required yaw rate calculator 14b.
[0065]
The allowable lateral acceleration calculation unit 14a is, for example, a vehicle speed V from the vehicle speed sensor 3, a longitudinal acceleration from the longitudinal acceleration sensor 6, a road surface friction coefficient estimation value μ from the vehicle specification calculation unit 11a, and a curve shape detection unit 12. The curve angle and curve direction of the forward curve are input, and the basic value ayl1n of the allowable lateral acceleration is calculated according to the road surface friction coefficient estimated value μ, and the basic value ayl1n of the allowable lateral acceleration is calculated as the vehicle speed V and the road gradient SL. The allowable lateral acceleration ayln is calculated with a predetermined correction in the curve angle and curve direction. The road gradient SL is calculated based on the rate of change of the vehicle speed V and the longitudinal acceleration.
[0066]
The necessary yaw rate calculation unit 14b receives the curve radius Rn and the allowable lateral acceleration ayln of the forward curve from the curve shape detection unit 12 and the allowable lateral acceleration calculation unit 14a, and the required yaw rate (dΨ / dt) in the forward curve. The
Necessary yaw rate (dΨ / dt) = ((Allowable lateral acceleration ayln on curve) / (Curve radius Rn))^1/2... (15)
And output to the braking force control device 9.
[0067]
The braking force control device 9 receives the current vehicle speed V, the steering wheel angle θH, and the yaw rate γ, and based on the input signals, the differential value of the target yaw rate, the differential value of the predicted yaw rate for low μ road travel, and both differential values The difference between the yaw rate γ and the target yaw rate is calculated, and based on these values, the vehicle understeer tendency or the target braking force that corrects the oversteer tendency is calculated, and the vehicle understeer tendency Is selected as a braking wheel to which braking force is applied, and a control signal is output to a brake drive unit (not shown) to correct the oversteer tendency. A braking force is controlled by adding a target braking force to the selected wheel.
[0068]
Here, when the control start signal is input from the control start determination / control unit 13 of the control unit 2, the braking force control device 9 is configured to perform the necessary operation on the forward curve calculated by the necessary yaw rate calculation unit 14 b. The yaw rate (dΨ / dt) is set as the target yaw rate, and the braking force control is performed based on the set target yaw rate.
[0069]
That is, the braking force control device 9 controls the behavior of the vehicle in accordance with the current driving situation except during curve driving. On the other hand, during curve driving, the control start signal is transmitted at a predetermined timing before entering the curve. Is input, the vehicle behavior control according to the road condition of the front curve is performed by setting the required yaw rate (dΨ / dt) as the target yaw rate.
[0070]
The device for controlling the behavior of the vehicle is not limited to the braking force control device 9. For example, in a four-wheel steering vehicle using the yaw rate as a control law parameter, the control unit 2 is connected to the four-wheel steering control device. When a control start signal is input from the control unit 2 to the four-wheel steering control device, the necessary yaw rate (dΨ / dt) is set as the target yaw rate in the same manner as the braking force control device 9, and the yaw angular velocity proportional steering is performed. Control or front wheel proportional steering may be performed, or a combination of these may be performed. Further, the braking force control device 9 and the four-wheel steering control device may be combined.
[0071]
The alarm device 10 maintains a safety when traveling on the curve ahead of the travel path by alerting the driver and encouraging control such as brake operation and steering of the steering wheel. When a control start signal is input, a predetermined alarm means (not shown) is driven to perform alarms such as a buzzer, an audio alarm, and a warning light. In other words, the alarm device 10 issues an alarm in accordance with the timing at which the control start signal is input to the forward curve, so that an alarm is issued at an appropriate timing that is earlier by a predetermined amount considering the behavioral delay of the vehicle. Is done.
[0072]
Next, the determination control of the vehicle motion control start timing for the forward curve according to the first embodiment of the present invention will be described with reference to the flowchart of FIG. This program is executed, for example, every predetermined time, and when the program starts, in step (hereinafter abbreviated as S) 101, the vehicle speed V, V, the vehicle speed sensor 3, the steering angle sensor 4, the yaw rate sensor 5, and the longitudinal acceleration sensor 6 are The steering wheel angle θH, yaw rate γ, and longitudinal acceleration signals are read, point data and road type information are read from the navigation device 7, and road width data is read from the road shape detection device 8, and the process proceeds to S102.
[0073]
In S102, the vehicle specification calculation unit 11a estimates the cornering powers Kf and Kr based on the vehicle speed V, the steering wheel angle θH, and the yaw rate γ, and calculates the road surface friction coefficient estimated value μ using the cornering powers Kf and Kr. Then, the process proceeds to S103.
[0074]
In S103, the yaw rate response time calculation unit 11b calculates the yaw rate response time tr by the equation (1) based on the vehicle speed V and the road surface friction coefficient estimated value μ, and the process proceeds to S104.
[0075]
In S104, the curve shape detection unit 12 detects a curve ahead of the traveling road based on the point data and road type information from the navigation device 7 and the road width data from the road shape detection device 8, and this detection is performed. The distance lc to the entrance of the forward curve is calculated, and the process proceeds to S105.
[0076]
In S105, the necessary yaw rate calculation unit 14 calculates the allowable lateral acceleration ayln based on the vehicle speed V, the road surface friction coefficient estimated value μ, the curve angle and curve direction of the forward curve, and the allowable lateral acceleration ayln and the forward curve. The required yaw rate (dΨ / dt) is calculated by the above equation (15) based on the curve radius Rn, and the process proceeds to S106.
[0077]
In S106, the control start determination / control unit 13 calculates the arrival time tc to the curve by the equation (13) based on the vehicle speed V and the distance l c to the front curve entrance, and the arrival time to this curve. Comparing tc with the yaw rate response time tr, when the arrival time tc to the curve is greater than the yaw rate response time tr, it is determined that it is not the vehicle motion control start timing, and the process returns to S101.
[0078]
On the other hand, when the arrival time tc to the curve is equal to or shorter than the yaw rate response time tr in S106, it is determined that the vehicle motion control start timing is reached, the process proceeds to S107, and the braking force control device 9 and the alarm device 10 are informed. Then, after outputting a predetermined signal (control start signal) for starting the vehicle motion control for the forward curve, the routine is exited.
[0079]
Here, when the control start signal is input to the braking force control device 9, the necessary yaw rate in the forward curve calculated by the necessary yaw rate calculation unit 14b is set as the target yaw rate, and the braking force is based on the target yaw rate. Take control. That is, by determining the motion control start timing in consideration of the response delay of the vehicle based on the yaw rate response time, the control start signal is input at an appropriate timing before entering the curve, and the control start signal is input. Since the required yaw rate (dΨ / dt) is set as the target yaw rate and the vehicle operation control according to the road condition of the forward curve is performed in advance at an appropriate timing before entering the curve, the optimal vehicle running state when entering the curve It is possible to maintain safety at a high level.
[0080]
When the control start signal is input to the alarm device 10, the alarm device 10 drives an alarm means (not shown) to give an alarm such as a buzzer, a sound alarm, a warning light, etc. , Urges a predetermined operation such as brake control. That is, by determining the motion control start timing in consideration of the response delay of the vehicle based on the yaw rate response time, the control start signal is input at an appropriate timing before entering the curve, and the control start signal is input. A predetermined warning can be issued to prompt the driver to perform vehicle control on the forward curve in advance, and a high level of safety can be achieved.
[0081]
As described above, according to the present embodiment, the yaw rate response time is calculated based on the vehicle speed V and the road surface friction coefficient estimated value μ, and the motion control is started in consideration of the response delay of the yaw rate of the vehicle based on the yaw rate response time. Since the timing can be determined, the motion control of the vehicle with respect to the forward curve can be performed at an appropriate timing, and a high level of safety maintenance can be realized.
[0082]
Next, FIGS. 8 to 10 show a second embodiment of the present invention, FIG. 8 is a block diagram showing the overall configuration of the vehicle motion control device, and FIG. 9 shows the yaw rate response time correction coefficient and the necessary yaw rate. FIG. 10 is an explanatory diagram of characteristics, and FIG. 10 is a flowchart of vehicle motion control start determination with respect to the forward curve. In the first embodiment described above, the yaw rate response time calculation unit 11 is mainly composed of the vehicle specification calculation unit 11a and the yaw rate response time calculation unit 11b, and the vehicle specification calculation unit 11a uses the road surface friction coefficient. While the estimated value μ is calculated and the yaw rate response time calculating unit 11b calculates the yaw rate response time tr based on the vehicle speed V and the road surface friction coefficient estimated value μ, in the present embodiment, the yaw rate response time calculating unit is calculated. 17 is mainly composed of a vehicle specification calculation unit 17a, a yaw rate response time reference value calculation unit 17b, and a yaw rate response time reference value correction unit 17c, and the vehicle specification calculation unit 17a calculates a road surface friction coefficient estimated value μ. The yaw rate response time reference value calculation unit 17b calculates the yaw rate response time reference value tr1 based on the vehicle speed V and the road surface friction coefficient estimated value μ, and the yaw rate response time. In the reference value correcting section 17c is for calculating the correction to the yaw rate response time tr with the yaw rate response time reference value tr1 required yaw rate (dΨ / dt). Other controls are substantially the same as those in the first embodiment described above, and the components for performing these controls are denoted by the same reference numerals and description thereof is omitted.
[0083]
The vehicle specification calculation unit 17a is similar to the vehicle specification calculation unit 11a described in the first embodiment, and the vehicle speed V from the vehicle speed sensor 3, the handle angle θH from the handle angle sensor 4, and the yaw rate sensor 5 are set. The data indicating the yaw rate γ from the vehicle is input, the cornering powers Kf and Kr of the front and rear wheels are estimated based on these data, and the road surface friction coefficient estimated value μ is estimated.
[0084]
The yaw rate response time reference value calculation unit 17b receives the vehicle speed V from the vehicle speed sensor 3 and the road surface friction coefficient estimated value μ from the vehicle specification calculation unit 11a. Based on these, the yaw rate response time reference value tr1 of the vehicle is obtained. It comes to calculate. Here, the calculation of the yaw rate response time reference value tr1 is a calculation method of the yaw rate response time tr in the yaw rate response time calculation unit 11b of the first embodiment, that is, a method of calculating by the above equation (1). It is the same.
[0085]
The yaw rate response time reference value correction unit 17c receives data indicating the necessary yaw rate calculation unit 14b, the necessary yaw rate (dΨ / dt), and the yaw rate response time reference value tr1 from the yaw rate response time reference value calculation unit 17b. The yaw rate response time tr1 is calculated by correcting the yaw rate response time reference value tr1 according to the required yaw rate (dΨ / dt), and is output to the control start determination / control unit 13.
[0086]
That is, in the yaw rate response time reference value correction unit 17c, the yaw rate response time tr is calculated by, for example,

Here, the correction coefficient K is a coefficient determined in advance so as to increase linearly as the required yaw rate (dΨ / dt) increases, for example, as shown in FIG. In other words, although the time constant of the yaw rate response is determined by the vehicle specifications, it is necessary to start the vehicle motion control as it is when the driver needs to steer greatly considering the steering speed of the driver. For this reason, by setting the yaw rate response time tr to be large, it is expressed that the control is started even if the arrival time to the curve is large.
[0087]
Next, the vehicle motion control start timing determination control for the forward curve according to the second embodiment of the present invention will be described with reference to the flowchart of FIG. This program is executed, for example, every predetermined time. When the program starts, in step S201, the vehicle speed V, the handle angle θH, and the yaw rate γ are obtained from the vehicle speed sensor 3, the handle angle sensor 4, the yaw rate sensor 5, and the longitudinal acceleration sensor 6. The longitudinal acceleration signals are read, the point data and road type information are read from the navigation device 7, and the road width data is read from the road shape detection device 8, and the process proceeds to S202.
[0088]
In S202, the vehicle specification calculation unit 17a estimates the cornering powers Kf and Kr based on the vehicle speed V, the steering wheel angle θH, and the yaw rate γ, and calculates the road surface friction coefficient estimated value μ using the cornering powers Kf and Kr. Then, the process proceeds to S203.
[0089]
In S203, the yaw rate response time reference value calculation unit 17b calculates the yaw rate response time reference value tr1 by replacing tr in the equation (1) with tr1 based on the vehicle speed V and the road surface friction coefficient estimated value μ. , Go to S204.
[0090]
In S204, the curve shape detection unit 12 detects a curve ahead of the traveling road based on the point data and road type information from the navigation device 7 and the road width data from the road shape detection device 8, and this detection is performed. The distance lc to the entrance of the forward curve is calculated, and the process proceeds to S205.
[0091]
In S205, the necessary yaw rate calculation unit 14 calculates the allowable lateral acceleration ayln based on the vehicle speed V, the road surface friction coefficient estimated value μ, the curve angle and curve direction of the forward curve, and the allowable lateral acceleration ayln and the forward curve. The necessary yaw rate (dΨ / dt) is calculated by the above equation (15) based on the curve radius Rn, and the process proceeds to S206.
[0092]
In S206, the yaw rate response time reference value correction unit 17c corrects the yaw rate response time reference value tr1 according to the required yaw rate (dΨ / dt), calculates the yaw rate response time tr using the equation (16), and The process proceeds to S207.
[0093]
In S207, the control start determination / control unit 13 calculates the arrival time tc to the curve by the equation (13) based on the vehicle speed V and the distance l c to the front curve entrance, and the arrival time to this curve. Comparing tc with the yaw rate response time tr, if the arrival time tc to the curve is greater than the yaw rate response time tr, it is determined that it is not the vehicle motion control start timing, and the process returns to S201.
[0094]
On the other hand, when the arrival time tc to the curve is equal to or shorter than the yaw rate response time tr in S207, it is determined that the vehicle motion control start timing is reached, the process proceeds to S208, and the braking force control device 9 and the alarm device 10 are informed. Then, after outputting a predetermined signal (control start signal) for starting the vehicle motion control for the forward curve, the routine is exited.
[0095]
As described above, in the present embodiment, the yaw rate response time reference value tr1 is obtained from the vehicle speed V, the cornering power Kr of the vehicle rear wheel, and the road surface friction coefficient estimated value μ, and the yaw rate response time reference value tr1 is obtained as the necessary yaw rate (dΨ / By correcting according to dt), it is possible to calculate a yaw rate response time tr that is more accurate than the yaw rate response time tr obtained in the first embodiment.
[0096]
Next, FIGS. 11 to 14 show a third embodiment of the present invention, FIG. 11 is a block diagram showing the overall configuration of the vehicle motion control device, and FIG. 12 is an explanatory diagram of a control start determination / control unit. FIG. 13 is a flowchart of vehicle motion control, and FIG. 14 is a flowchart of a control start determination subroutine. In this embodiment, the present applicant performs the vehicle motion control shown in Japanese Patent Application No. 9-245788 in consideration of the yaw rate response of the vehicle.
[0097]
In FIG. 11, reference numeral 1b indicates the overall configuration of the vehicle motion control device mounted on the vehicle. The vehicle motion control device 1b includes a vehicle speed sensor 3, a handle angle sensor 4, a yaw rate sensor 5, a longitudinal acceleration. Vehicle speed V, steering wheel angle θH, yaw rate γ, longitudinal acceleration signals detected by each sensor of sensor 6, point data and road type information of road data from navigation device 7, road width from road shape detection device 8, and the like. Data relating to the shape of the road and an operation signal (signal indicating the turning operation of the driver) from the turn signal switch 31 are input.
[0098]
The controller 2b sufficiently stabilizes the curve ahead of the traveling road based on the inputs from the sensors 3, 4, 5, 6, the navigation device 7, the road shape detection device 8, and the turn signal switch 31. If it is necessary to forcibly decelerate, a warning is given to the driver through the alarm device 35 such as a buzzer, voice alarm, warning light, etc. At the time of deceleration), in addition to the alarm, the transmission control device 32 is shifted down, the engine control device 33 is reduced in boost pressure, the fuel cut and the throttle opening are fully closed (closed control), the brake The control device 34 is made to execute the brake operation and the brake force increase (alarm / deceleration control is performed). Here, in the present embodiment, vehicle behavior control and alarm output by the devices 32 to 35 are performed at a timing in consideration of the yaw rate response distance of the vehicle.
[0099]
The transmission control device 32 performs transmission-related control such as vehicle shift control, lock-up control, and line pressure control, and outputs the current shift position to the control unit 2b. When a downshift execution signal from 2b is input, downshifting is performed.
[0100]
The engine control device 33 performs control related to the engine such as fuel injection control, ignition timing control, air-fuel ratio control, supercharging pressure control, throttle opening control, and the like. The control information, fuel cut information, and throttle opening control information are output, and when the boost pressure down execution signal is input from the control unit 2b, the boost pressure down is input and the fuel cut execution signal is input. When the throttle opening fully closed (closed control) execution signal is input, the throttle opening fully closed (closed control) is performed.
[0101]
The brake control device 34 is connected to a hydraulic unit to perform anti-lock brake control, automatic brake control, and the like. The brake control device 34 outputs the current brake operation state to the control unit 2b and also controls the control unit 2b. Thus, when a signal for executing the brake operation and the brake force increase is input, the brake operation and the brake force increase are performed.
[0102]
The alarm device 35 is configured by a chime / buzzer, a sound alarm, a warning light, or a combination thereof. For example, at the time of alarm, the alarm device 35 is recorded in advance on the CD-ROM of the navigation device 7. "Decelerate because of a curve." Or an alarm with only a chime / buzzer sound. During forced deceleration, turn on the buzzer and warning light such as "Decelerate because of a curve." To do. Note that the method of alarming is not limited to this, and a plurality of voice warnings may be used separately to issue warnings during warnings and forced decelerations. Further, the position of a curve to be controlled for alarm / deceleration may be displayed in color on a map of an information display unit (not shown) of the navigation device 7 or may be guided by voice.
[0103]
The control unit 2b mainly includes a yaw rate response time calculation unit 11, a curve shape detection unit 12, an allowable lateral acceleration calculation unit 36, and a control start determination / control unit 38.
[0104]
The allowable lateral acceleration calculation unit 36 is, for example, the vehicle speed V from the vehicle speed sensor 3, the longitudinal acceleration from the longitudinal acceleration sensor 6, the road surface friction coefficient estimated value μ from the vehicle specification calculation unit 11 a, and the curve shape detection unit 12. The curve angle and curve direction of the forward curve are input, and the basic value ayl1n of the allowable lateral acceleration is calculated according to the road surface friction coefficient estimated value μ, and the basic value ayl1n of the allowable lateral acceleration is calculated as the vehicle speed V and the road gradient SL. The allowable lateral acceleration ayln is calculated with a predetermined correction in the curve angle and curve direction. The road gradient SL is calculated based on the rate of change of the vehicle speed V and the longitudinal acceleration.
[0105]
The control start determination / control unit 38 includes a vehicle speed V from the vehicle speed sensor 3, a handle angle θH from the handle angle sensor 4, a longitudinal acceleration from the longitudinal acceleration sensor 6, and a road surface friction coefficient estimation value from the vehicle specification calculation unit 11 a. μ, yaw rate response time tr from the yaw rate response time calculator 11b, curve radius Rn from the curve shape detector 12, motion signal from the turn signal switch 31, allowable lateral acceleration ayln from the allowable lateral acceleration calculator 36, In response to an input, a signal is output to the alarm device 35 to perform alarm control, and a signal is output to each of the control devices 32 to 34 to perform deceleration control.
[0106]
More specifically, as shown in FIG. 12, the control start determination / control unit 38 includes a reference allowable approach speed setting unit 40, an allowable deceleration setting unit 41, a control execution determination unit 42, a deceleration speed calculation / output unit 43, The alarm speed calculation / output unit 44 is mainly configured.
[0107]
The yaw rate response distance calculation unit 37 receives the vehicle speed V from the vehicle speed sensor 3 and the yaw rate response time tr from the yaw rate response time calculation unit 11b. For example, according to the equation (14) shown in the first embodiment described above. The yaw rate response distance lr is calculated.
[0108]
The reference allowable approach speed setting unit 40 is based on an allowable approach speed (reference allowable approach based on the curvature radius Rn of the curve from the curve shape detection unit 12 and the allowable lateral acceleration ayln from the allowable lateral acceleration calculation unit 36. Speed Vpn) is set, and each set reference allowable approach speed Vpn is output to the deceleration speed calculation / output unit 43 and the alarm speed calculation / output unit 44.
[0109]
The calculation of the reference allowable approach speed Vpn in the reference allowable approach speed setting unit 40 is performed by the following equation.
Vpn = (ayln ・ Rn)^1/2                    ... (17)
[0110]
The permissible deceleration setting unit 41 sets a permissible deceleration (allowable deceleration XgLim) according to the road surface condition of the road surface friction coefficient estimated value μ and the road gradient SL, and the permissible deceleration XgLim is the deceleration described above. It is output to the speed calculation / output unit 43 and the alarm speed calculation / output unit 44.
[0111]
That is, the allowable deceleration setting unit 41 first sets the basic value XgLim0 from the road surface friction coefficient estimated value μ calculated by the vehicle specification calculation unit 11a, for example, as follows.
XgLim0 = μ · g · Kμ2 (18)
Here, the coefficient K.mu.2 is set to a value of, for example, about K.mu.2 = 0.8 in consideration of the road surface utilization during full braking. The constant axc is set in advance by experiment, calculation, etc., for example, 5 m / s²And so on.
[0112]
Further, in the allowable deceleration setting unit 41, as shown in the following equation (19), correction is made for the change of the braking distance due to the road gradient SL, and at the same time, the deceleration acceleration felt by the driver is made constant so as to be constant. The basic value XgLim0 is corrected so as to obtain a large deceleration at the gradient and a small deceleration at the descending gradient, thereby obtaining the allowable deceleration XgLim. By such correction, the control start timing takes into account the deceleration component of gravity due to the gradient on the uphill and the acceleration component of gravity on the downhill.
XgLim = XgLim0 + g · SL / 100 (19)
[0113]
The control execution determination unit 42 receives a signal from the turn signal switch 31 and the vehicle speed sensor 3 and a signal from the steering wheel angle sensor 4. ), Cancellation of alarm / deceleration control (OFF), change from deceleration control to alarm control, and output to the deceleration speed calculation / output unit 43 and the alarm speed calculation / output unit 44.
[0114]
That is, when the driver operates the turn signal switch 31, an approach to a straight road that is not included in the map information of the navigation device 7 or an erroneous determination of a curve and an intersection is expected. Is to be released.
[0115]
In addition, if the driver performs a steering operation beyond the steering amount set in advance by the signal from the steering wheel angle sensor 4, traveling other than the expected course is expected. The control is released.
[0116]
When performing the alarm control by the signal from the vehicle speed sensor 3, if the driver has already decelerated more than the deceleration (0.5 · XgLim) in the alarm determination, the driver is already dealing with Yes, alarm control is canceled because it is not necessary to issue an alarm. In this case, if a plurality of alarm methods can be changed, the alarm method may be changed to perform the alarm.
[0117]
Further, when the driver has already decelerated more than the deceleration (0.8 · XgLim) in the deceleration determination when performing the deceleration control based on the signal from the vehicle speed sensor 3, the driver has already dealt with Since there is no need to perform forced deceleration, the deceleration control is changed to alarm control.
[0118]
The alarm speed calculation / output unit 44 receives data of points,..., Pn-1, Pn,... In front of the vehicle from the curve distance detection unit 12, and calculates a distance Ln between these points. At the same time, based on the distance Ln, the allowable deceleration XgLim set by the allowable deceleration setting unit 41, and the reference allowable approach speed Vpn set by the reference allowable approach speed setting unit 40, the allowable limit used as a reference for alarm control The approach speed is calculated as the alarm speed VA. Each alarm speed VA calculated by the alarm speed calculation / output unit 44 is stored in a predetermined memory together with a deceleration speed VB described later.
[0119]
In addition, the yaw rate response distance lr is input from the yaw rate response distance calculation unit 37 to the alarm speed calculation / output unit 44. For example, an acceleration capable of decelerating a threshold for an alarm considering the yaw rate response distance lr, that is, an allowable The speed is set as 50% of the deceleration XgLim.
[0120]
The alarm judgment speed (alarm speed VA = VA12) at the arrival point P1 (point P2 to point P1 = L2) with respect to the preceding point P2 is the passable speed at the point P2 (= reference allowable approach speed Vp2).
VA12 = (Vp2²+2 ・ (0.5 ・ XgLim) ・ (L2－lr))^1/2
Similarly, the alarm speed VA (= VA13) at the arrival point P1 (point P3 to point P1 = L2 + L3) with respect to the preceding point P3 is equal to the reference allowable approach speed Vp3.
VA13 = (Vp3²+2 · (0.5 · XgLim) · (L2 + L3-lr))^1/2
Thus, the warning speed VA (= VAαβ) at the arrival point Pα (point Pβ to point Pα = L (α + 1) +... + Lβ) with respect to the preceding point Pβ is equal to the reference allowable approach speed VPβ.
VAαβ = (VPβ²+ 2 · (0.5 · XgLim) · (L (α + 1) +... + Lβ−lr))^1/2  ... (20)
Further, the alarm speed calculation / output unit 44 converts each of the alarm speeds VA1β (VA1 (n + 1) to Vp1) into an alarm speed at the current position point P0 based on the distance L1 and the allowable deceleration XgLim. The estimated alarm speed VAP is calculated, and the estimated alarm speed VAP is compared with the vehicle speed V. When the vehicle speed V is equal to or higher than the estimated alarm speed VAP, a signal is output to the alarm device 35 to perform alarm control. ing. The execution of the alarm control can be canceled by a signal from the control execution determination unit 42 or can be started by a change from the deceleration control.
[0121]
Here, the estimated alarm speed VAP is calculated as follows.
From the above equation (20), the warning speed VA (= VA0β = VAP) at the arrival point P0 (point Pβ to point P0 = L1 + L2 +... + Lβ) with respect to the preceding point Pβ is equal to the reference allowable approach speed VPβ.
VAP = (VPβ²+2 · (0.5 · XgLim) · (L1 + L2 + ... + Lβ-lr))^1/2
Further, the alarm speed VA (= VA1β) at the arrival point P1 (point Pβ to point P1 = L2 +... + Lβ) with respect to the preceding point Pβ is equal to the reference allowable approach speed VPβ.
VA1β = (VPβ²+2 · (0.5 · XgLim) · (L2 + ... + Lβ-lr))^1/2
Therefore, from these two equations,
VAP = (VA1β²+2 ・ (0.5 ・ XgLim) ・ (L1－lr))^1/2... (21)
[0122]
The deceleration speed calculation / output unit 43 receives data of each point in front of the vehicle,..., Pn-1, Pn,... From the curve distance detection unit 12, and calculates a distance Ln between these points. At the same time, the allowable deceleration XgLim set by the allowable deceleration setting unit 41 and the reference allowable approach speed Vpn set by the reference allowable approach speed setting unit 40 are input, and the allowable approach speed used as a reference for deceleration control is determined. It is calculated as the deceleration speed VB.
[0123]
Further, the yaw rate response distance lr is input from the yaw rate response distance calculation unit 37 to the deceleration speed calculation / output unit 43. For example, an acceleration capable of decelerating a threshold for forced deceleration considering the yaw rate response distance lr, that is, The speed is set as 80% of the allowable deceleration XgLim.
[0124]
The forced deceleration determination speed (deceleration speed VB = VB12) at the arrival point P1 (point P2 to point P1 = L2) with respect to the preceding point P2 is compared with the speed that can be passed at the point P2 (= reference allowable approach speed Vp2). ,
VB12 = (Vp2² +2 ・ (0.8 ・ XgLim) ・ (L2－lr))^1/2
Similarly, the deceleration speed VB (= VB13) at the arrival point P1 (point P3 to point P1 = L2 + L3) with respect to the preceding point P3 is equal to the reference allowable approach speed Vp3.
VB13 = (Vp3²+2 ・ (0.8 ・ XgLim) ・ (L2 + L3 -lr))^1/2Thus, the deceleration speed VB (= VBαβ) at the arrival point Pα (point Pβ to point Pα = L (α + 1) +... + Lβ) with respect to the preceding point Pβ is equal to the reference allowable approach speed VPβ.
VBαβ = (VPβ²+ 2 · (0.8 · XgLim) · (L (α + 1) +... + Lβ−lr))^1/2  ... (22)
Further, the deceleration speed calculation / output unit 43 converts the deceleration speeds VB1β (VB1 (n + 1) to Vp1) into deceleration speeds at the current position point P0 based on the distance L1 and the allowable deceleration XgLim. The estimated deceleration speed VBP is calculated, and the estimated deceleration speed VBP and the vehicle speed V are respectively compared, and a signal is sent to perform the deceleration control when the vehicle speed V is equal to or higher than the estimated deceleration speed VBP, according to the allowable deceleration XgLim. It outputs to each control apparatus 32-34 predetermined. The execution of deceleration control can be canceled or changed to alarm control by a signal from the control execution determination unit 42. In the deceleration control, a signal is output from the alarm device 35 so as to give an alarm to that effect (lamp lighting, sound generation, etc.).
[0125]
Here, the estimated deceleration speed VBP is calculated as follows.
From the above equation (22), the deceleration speed VB (= VB0β = VBP) at the arrival point P0 (point Pβ to point P0 = L1 + L2 +... + Lβ) with respect to the preceding point Pβ is equal to the reference allowable approach speed VPβ.
VBP = (VPβ²+2 · (0.8 · XgLim) · (L1 + L2 + ... + Lβ-lr))^1/2
In addition, the alarm speed VB (= VB1β) at the arrival point P1 (point Pβ to point P1 = L2 +... + Lβ) with respect to the preceding point Pβ is equal to the reference allowable approach speed VPβ.
VB1β = (VPβ²+2 · (0.8 · XgLim) · (L2 + ... + Lβ-lr))^1/2
Therefore, from these two equations,
VBP = (VB1β²+2 ・ (0.8 ・ XgLim) ・ L1 -lr)^1/2... (23)
In addition, the deceleration control is performed in accordance with the allowable deceleration XgLim. The engine control device 33 performs a boost pressure down + fuel cut, or the engine control device 33 performs a boost pressure down + fuel. Execution of cut + throttle opening closing control, or boost pressure reduction for the engine control device 33 + fuel cut + throttle opening full closing execution + shift down execution for the transmission control device 32, or engine control Select one of boost pressure reduction for the device 33 + fuel cut + full throttle opening + shift down execution for the transmission control device 32 + brake operation and brake force increase for the brake control device 34 It is supposed to be done.
[0126]
Next, vehicle motion control start control according to the third embodiment of the present invention will be described with reference to the flowchart of FIG. This program is executed, for example, every predetermined time, and when the program is started, in step S301, the vehicle speed V, the steering wheel is detected from the vehicle speed sensor 3, the handle angle sensor 4, the yaw rate sensor 5, the longitudinal acceleration sensor 6, and the turn signal switch 31. The angle θH, yaw rate γ, longitudinal acceleration, and motion signals are read, point data and road type information are read from the navigation device 7, and road width data is read from the road shape detection device 8, and the process proceeds to S302.
[0127]
In S302, the vehicle specification calculation unit 11a estimates the cornering powers Kf and Kr based on the vehicle speed V, the steering wheel angle θH, and the yaw rate γ, and calculates the road surface friction coefficient estimated value μ using the cornering powers Kf and Kr. Then, the process proceeds to S303.
[0128]
In S303, the yaw rate response time reference value calculation unit 11b calculates the yaw rate response time tr by the equation (1) based on the vehicle speed V and the road surface friction coefficient estimated value μ, and the process proceeds to S304.
[0129]
In S304, the curve shape detection unit 12 detects a curve ahead of the traveling road based on the point data and road type information from the navigation device 7 and the road width data from the road shape detection device 8, and this detection is performed. The distance lc to the entrance of the forward curve is calculated, and the process proceeds to S305.
[0130]
In S305, the allowable lateral acceleration calculator 36 calculates the allowable lateral acceleration ayln based on the vehicle speed V, the road surface friction coefficient estimated value μ, the curve angle and curve direction of the forward curve, and the process proceeds to S306.
[0131]
In S306, the control start determination / control unit 38 performs control start determination of the transmission control device 32, the engine control device 33, the brake control device 34, and the alarm device 35 by a subroutine described below. After executing the necessary control by .about.35, the routine is exited.
[0132]
Next, when the control start determination subroutine performed by the control start determination / control unit 38 is started, in step S311, the yaw rate response distance calculation unit 37 calculates (14) based on the vehicle speed V and the yaw rate response time tr. ) To calculate the yaw rate response distance lr, and the process proceeds to S312.
[0133]
In S312, the reference allowable approach speed setting unit 40 sets the reference allowable approach speed Vpn based on the curvature radius Rn of the curve and the allowable lateral acceleration ayln, and the process proceeds to S313.
[0134]
In S313, the allowable deceleration setting unit 41 sets the allowable deceleration XgLim in accordance with the road surface friction coefficient estimated value μ and the road condition of the road gradient SL, and the process proceeds to S314.
[0135]
When the process proceeds to S314, it is determined whether or not the turn signal switch 31 is operated. If the turn signal switch 31 is operated, the process proceeds to S315, the deceleration control is canceled (OFF), the process proceeds to S316, and the alarm control is performed. Is released (OFF) to exit the routine.
[0136]
On the other hand, if it is determined in S314 that the turn signal switch 7 is not operated, the process proceeds to S317, and it is determined whether or not the steering amount by the driver is greater than or equal to a preset value based on a signal from the steering wheel angle sensor 4. . If the steering amount by the driver is equal to or larger than the set value, the process proceeds to S315 to cancel the deceleration control (OFF), proceeds to S316, cancels the alarm control (OFF), and exits the routine.
[0137]
If it is determined in S317 that the steering amount is smaller than the set value (when the turn signal switch 31 is OFF and the steering amount is small), the process proceeds to S318, and each data (point P1) at the deceleration speed calculation / output unit 43 ( Based on the respective deceleration speeds VB1β (VB1 (n + 1) to Vp1)), the deceleration speed at the current position point P0 is estimated and calculated (estimated deceleration speed VBP). At this time, each estimated deceleration speed is calculated in consideration of the yaw rate response distance lr.
[0138]
Then, the process proceeds to S319, where the vehicle speed V is compared with each estimated deceleration speed VBP. If the vehicle speed V is one or more of the estimated deceleration speeds VBP (V ≧ VBP), the process proceeds to S320. .
[0139]
In S320, based on the vehicle speed V, it is determined whether or not the driver has already decelerated more than the deceleration (0.8 · XgLim) in the deceleration determination. If the driver does not decelerate more than the deceleration determined in the deceleration determination, it is determined that deceleration is necessary, the process proceeds to S321, deceleration control is executed (ON), and the routine is exited.
[0140]
Further, in S320, if the driver has already performed deceleration more than the deceleration (0.8 · XgLim) in the deceleration determination, the driver is already handling and there is no need to perform forced deceleration. The process proceeds to S322, where deceleration control is released (OFF), and further proceeds to S323 where alarm control is executed (ON) (that is, the control is changed from deceleration control to alarm control) and the routine is exited.
[0141]
On the other hand, if the vehicle speed V is smaller than all the estimated deceleration speeds VBP as a result of the comparison between the vehicle speed V and the estimated deceleration speeds VBP in S319, the process proceeds to S324 and the deceleration control is canceled (OFF). Proceeding to S325, the alarm speed calculation / output unit 44 estimates and calculates the alarm speed at the current position point P0 based on the data at each point P1 (each alarm speed VA1β (VA1 (n + 1) to Vp1)) ( Estimated alarm speed VAP). At this time, the calculation of each estimated alarm speed is performed in consideration of the yaw rate response distance lr, similarly to the calculation of the estimated deceleration speed.
[0142]
Then, the process proceeds to S326, where the vehicle speed V is compared with each estimated alarm speed VAP. If the vehicle speed V is one or more of the estimated alarm speeds VAP (V ≧ VAP), the process proceeds to S327. .
[0143]
In S327, based on the vehicle speed V, it is determined whether or not the driver has already decelerated more than the deceleration (0.5 · XgLim) in the alarm determination. If the driver does not decelerate more than the deceleration determined in the alarm determination, it is determined that the alarm is necessary, the process proceeds to S323, the alarm control is executed (ON), and the routine is exited.
[0144]
Further, in S327, if the driver has already decelerated more than the deceleration (0.5 · XgLim) in the alarm determination, it is determined that the driver is already dealing with it and does not need to issue an alarm. Then, the process proceeds to S328, the alarm control is canceled (OFF), and the routine is exited.
[0145]
Here, the alarm control execution (ON) of S323 is performed by the alarm device 35 constituted by a chime buzzer, a sound alarm generation, a warning light, or a combination thereof, as described above. In the alarm control performed after that, for example, a voice alarm such as “Decelerate because of a curve” or an alarm only for the chime / buzzer sound is performed. Sound only alarm.
[0146]
When the deceleration control is executed (ON) in S321, the alarm device 35 turns on a sound alarm such as “Decelerates because of a curve”, a buzzer, and a warning lamp. Here, the deceleration control executed by the deceleration speed calculation / output unit 43 is executed to perform a boost pressure down + fuel cut for the engine control device 33 according to the allowable deceleration XgLim, or the engine. Execution of supercharging pressure down + fuel cut + throttle opening closing control for the control device 33 or execution of supercharging pressure down + fuel cut + throttle opening full closing for the engine control device 33 + transmission control device Execute shift down to 32, or reduce supercharging pressure to the engine control device 33 + execute fuel cut + fully close throttle opening + execute shift down to the transmission control device 32 + brake operation to the brake control device 34 One of execution of the braking force increase is selected and performed.
[0147]
The determination processes of S312, S317, S320, and S327 are performed by the control execution determination unit 31.
[0148]
As described above, also in the present embodiment, as in the first and second embodiments of the present invention described above, the vehicle motion control with respect to the forward curve is an appropriate one considering the vehicle yaw rate response (yaw rate response distance). It can be done at the timing, and it is possible to achieve a high level of safety maintenance.
[0149]
【The invention's effect】
As described above, according to the present invention, the yaw rate response time is calculated from the running state of the vehicle, and the start timing of the vehicle motion control with respect to the forward curve is determined based on the yaw rate response time. The motion control can be started at an appropriate timing considering the behavior delay of the vehicle with respect to the future behavior that is sometimes predicted, and the stability can be improved at a high level. In addition, the yaw rate response time is calculated from the running state of the vehicle, the yaw rate response distance is calculated based on the yaw rate response time, and the yaw rate response distance is reflected in the motion control of the vehicle. The motion control can be started at a proper timing, and the stability can be improved at a high level.
[Brief description of the drawings]
FIGS. 1 to 7 show a first embodiment of the present invention, and FIG. 1 is a block diagram showing the overall configuration of a vehicle motion control device
FIG. 2 is an explanatory diagram of a configuration of a curve shape detection unit
FIG. 3 is an explanatory diagram of how to find the curvature radius of a curve.
FIG. 4 is an explanatory diagram of correction of the calculated curvature radius of a curve.
FIG. 5 is an explanatory diagram of an example of point data actually obtained from the navigation device.
FIG. 6 is an explanatory diagram of each case in the data organizing unit.
FIG. 7 is a flowchart of vehicle motion start determination control.
8 to 9 show a second embodiment of the present invention, and FIG. 8 is a block diagram showing an overall configuration of a vehicle motion control device.
FIG. 9 is an explanatory diagram of characteristics of a yaw rate response time correction coefficient and a necessary yaw rate.
FIG. 10 is a flowchart of vehicle motion start determination control for a forward curve.
FIGS. 11 to 14 show a third embodiment of the present invention, and FIG. 11 is a block diagram showing an overall configuration of a vehicle motion control device.
FIG. 12 is an explanatory diagram of a control start determination / control unit.
FIG. 13 is a flowchart of vehicle motion start determination control.
FIG. 14 is a flowchart of a control start determination subroutine.
[Explanation of symbols]
9: Braking force control device
10 ... Alarm device
11: Yaw rate response time calculation unit (yaw rate response time calculation means)
12 ... Curve shape detection unit (curve shape detection means)
13: Control start determination / control unit (control start determination / control means)
14 ... Necessary yaw rate calculation unit (necessary yaw rate calculation means)

Claims (6)

In a vehicle motion control apparatus that detects a vehicle running state and performs vehicle motion control by performing at least one of vehicle behavior control and alarm control according to the detected running state.
A yaw rate response time calculating means for calculating a road surface friction coefficient estimated value based on the running state and calculating a time until the yaw rate of the vehicle responds when the vehicle is steered based on the road surface friction coefficient estimated value and the vehicle speed;
A curve shape detecting means for detecting a curve in front of the traveling path and calculating a distance from the vehicle to the forward curve;
Based on the yaw rate response time calculated by the yaw rate response time calculation means and the distance to the front curve calculated by the curve shape detection means, a control start determination for determining and controlling the start of vehicle motion control for the front curve And a vehicle motion control device. The allowable lateral acceleration when traveling on the front curve is calculated based on the vehicle running state and the road surface state, and the front side is calculated based on the allowable lateral acceleration and the curvature radius of the front curve detected by the curve shape detecting means. Having necessary yaw rate calculating means for calculating the yaw rate of the vehicle required when traveling on a curve,
2. The yaw rate response time calculating means uses a value obtained by correcting the yaw rate response time calculated based on the estimated road surface friction coefficient and the vehicle speed according to the required yaw rate as the yaw rate response time. Vehicle motion control device.   The control start determination / control means calculates a time until the vehicle reaches the forward curve based on the vehicle speed and the distance to the forward curve of the vehicle calculated by the curve shape detection means. The vehicle motion control according to any one of claims 1 and 2, wherein the start of vehicle motion control is determined by comparing the arrival time of the vehicle and the yaw rate response time calculated by the yaw rate response time calculation means. apparatus. The control start determination / control means calculates a yaw rate response distance when the vehicle is controlled based on the vehicle speed and the yaw rate response time of the vehicle calculated by the yaw rate response time calculation means, and the yaw rate response distance The vehicle motion control device according to any one of claims 1 and 2, wherein the start of vehicle motion control is determined by comparing the distance to the front curve of the vehicle calculated by the curve calculation means. .   The control start determination / control means calculates a yaw rate response distance when the vehicle is controlled based on the vehicle speed and the yaw rate response time of the vehicle calculated by the yaw rate response time calculation means, and calculates the yaw rate response distance. The vehicle motion control device according to any one of claims 1 and 2, wherein start of vehicle motion control is determined based on the basis. Based on the running state of the vehicle and the road surface condition, an allowable lateral acceleration at the time of traveling on the forward curve is calculated, and the forward curve is calculated based on the allowable lateral acceleration and a curvature radius of the forward curve detected by the curve shape detecting means. A necessary yaw rate calculating means for calculating a required yaw rate of the vehicle in
In the case where the vehicle behavior control is a braking control in which a braking force is independently applied to a wheel selected based on a target yaw rate obtained based on the running state of the vehicle, the required yaw rate is set as a target when the braking force control is performed. 6. The vehicle motion control device according to claim 1, wherein the vehicle motion control device is set as a yaw rate.

Images