JP4258285B2 - Vehicle braking force control device - Google Patents

Description

【００２０】
である。ただし、ａ、ｂ、ｃ、ｄ、ｅは定数である。
ステップＳ１６０では、実ヨーレイトｄφ、車両ＷＶの前後方向・左右方向の加速度ＤＤＸ、ＤＤＹ、車体速度Ｖから前記目標直線軌跡を基準とした車両ＷＶのヨー角φを演算して、ステップＳ１７０に移行する。
ステップＳ１７０では、路面の状況に対応する悪路補正係数Ｋａをもとに悪路判定を行い、悪路の場合すなわちＫａ＜１．０である場合は、ステップＳ１８０に移行して修正舵判断のステップへ進み、悪路ではない場合すなわちＫａ＝１．０の場合は、修正舵判断を実行せずステップＳ２１０に移行する。
【００２１】
ステップＳ１８０では、車両ＷＶが前記不感帯ＤＺの中にいるかどうかを判定する。車両ＷＶが不感帯ＤＺを逸脱している場合はステップＳ１９０に移行し、不感帯ＤＺ内に位置すると判定した場合には旋回安定のための自動減速制御を作動させることなく復帰する。
ステップＳ１９０では、直線目標軌跡に戻る方向に操舵しているかどうかを判定し、直線目標軌跡から離脱する方向に操舵していると判定している場合には、Ｓ２００に進み、直線目標軌跡に戻る方向に操舵していると判定した場合は修正舵を与えていると判断して、旋回安定のための自動減速制御を作動させることなく復帰する。
【００２２】
ステップＳ２００では、直線目標軌跡に対し車両ＷＶのヨー角φが離脱する方向を向いているか否かを判定する。直線目標軌跡に戻る方向の場合は進路修正するための修正操舵中であると判断し、旋回安定のための自動減速制御を作動させることなく復帰する。一方、車両ＷＶのヨー角φが直線目標軌跡を離脱する方向と判定した場合は、旋回安定のための自動減速制御を行うためにステップＳ２１０に移行する。
【００２３】
ここで、上述の修正舵の判断として、操舵角速度、操舵角加速度、操舵トルクの変化量の絶対値が大きいほど修正舵であると判断するステップを追加しても良い。
ステップＳ２１０では、各車輪速度、および車体速度Ｖから各輪のスリップ率ＳFL、ＳFR、ＳRL、ＳRRを求める。ステップＳ２２０では、車体速度Ｖおよび車体左右加速度ＤＤＹから、下記式に基づき旋回半径Ｒを演算してステップＳ２３０に移行する。
【００２４】
Ｒ ＝（Ｖ² ／ＤＤＹ）
ステップＳ２３０では、現在の車体速度Ｖにおける限界旋回半径ＲＬを車体速度Ｖから求める。例えば、車両ＷＶによって定まる限界車体左右加速度をＤＤＹ１とすると、ＲＬ＝（Ｖ² ／ＤＤＹ１）で求めることができる。
続いてステップＳ２４０では、現在の旋回半径Ｒにおける限界旋回速度ＶL を、旋回半径Ｒから下記式に基づき求めステップＳ２５０に移行する。
【００２５】
ＶL ＝√（Ｒ・ＤＤＹ１）
ここで、上記の限界車体左右加速度ＤＤＹ１は、各輪のスリップ率ＳFL、ＳFR、ＳRL、ＳRRに応じて変化させてもよい。また、各輪のスリップ率ＳFL、ＳFR、ＳRL、ＳRRの状態によってはアンチスキッド、またはトラクションコントロールの制御を優先させてもよい。
【００２６】
ステップＳ２５０では、旋回半径Ｒが限界旋回半径ＲＬに対して、または、車体速度Ｖが限界旋回車速ＶL に対してどういう値にあるかを判断し、作動閾値である許容値ｋＶL 、ｈＲL （但しｋ、ｈ＜１）を越えた場合、つまり車体速度Ｖが許容値ｋＶL よりも大きくなっているか、旋回半径Ｒが許容値ｈＲL よりも小さい半径となっている場合には制動制御の処理を行うべくステップＳ２６０に移行し、許容値を越えない場合には処理を終了して復帰する。ここで、上記許容値ｋＶL ，ｈＲL の係数ｋ、ｈ（ｋ、ｈは１よりも若干小さい係数）を予め定めておく。
【００２７】
ステップＳ２６０では、車体速度Ｖ、限界車体速度ＶL 、旋回半径Ｒ、限界旋回半径ＲL に基づき、目標減速度ＸＧＣＯを演算し、ステップＳ２７０に移行する。
ステップＳ２７０では、上記目標減速度ＸＧＣＯを得るための前後輪の各目標ブレーキ液圧を求め、ステップＳ２８０に移行する。
ステップＳ２８０では、圧力切り換え弁７をＯＮ（第３図右側の状態）にする。これによりアキュムレータ内の液圧がプランジャに作用して、該プランジャ内の圧液が圧力調整器１１，２１，３１，４１側に送られる。
【００２８】
ステップＳ２９０では、各輪毎に配分され目標ブレーキ液圧を得るのに必要な圧力調整器１１，２１，３１，４１の各ソレノイドへの供給電流ｉＦＬ、ｉＦＲ、ｉＲＬ、ｉＲＲを求め、ステップＳ３００にて各ソレノイドに電流を供給してブレーキ圧力制御を行うことにより車両ＷＶの減速度を得る。すなわち、圧力調整器１１，２１，３１，４１について、それぞれ弁位置を図２の左側の位置にすると、プランジャ５，６からブレーキのキャリパ１２，２２，３２，４２へ圧液が送られて、ブレーキ液圧が増圧される。また、弁位置が中立位置にあるときには、液路が遮断されることによりブレーキ液圧は一定に保持される。一方、弁位置が右側の位置にあるときにはブレーキ液はリザーバタンク２０，４０側へ戻される。このように圧力調整器１１，２１，３１，４１の切換位置を制御することにより各輪のブレーキ圧が制御される。なお、リザーバタンク２０，４０の圧液はポンプ１９，２９によりリザーバタンク３に戻される。
【００２９】
一方、ステップＳ３１０では、目標減速度ＸＧＣＯを得るためのエンジン出力制御信号を演算する。例えば、スロットル開度によりエンジン出力を制御する場合には、ブレーキによって得られる減速度との関係を考えて目標スロットル開度を決定し、目標スロットル開度を得るための制御信号を演算する。続いて、ステップＳ３２０で、エンジン出力調整器を駆動する。前記した例ではスロットルを駆動することになる。
【００３０】
ここで、ステップＳ２１０〜Ｓ３２０が旋回判定制御手段を、Ｓ１８０〜Ｓ２００の各処理が修正舵検出手段を、ステップＳ１４０が走行軌跡演算手段を、ステップＳ１５０が直進目標軌跡演算手段をそれぞれ構成する。
次に、上記構成の動作や作用・効果などについて説明する。
車両ＷＶの旋回時に、車両ＷＶが安定して旋回可能な限界に近づくと、積極的に車両ＷＶを減速させて、運転者の意志にかかわらず車両ＷＶが安定して旋回可能な限界を越えないように制動制御される。
【００３１】
ここで、直進走行時において、轍や凹凸の多い路面など、いわゆる悪路を走行している状態では、路面からの外乱によって車輪に左右方向の力が作用して予定していない車両挙動が生じ、それに対処しようと目的とする進行方向に車両ＷＶの走行方向を戻そうとして、運転者は修正操舵を行う。また、横風などの外乱によっても予定していない車両挙動が生じ運転者は修正操作を行う。
【００３２】
上記修正操舵は、通常、舵角速度が大きかったり所要の左右加速度が車体に発生することから、旋回安定制御手段は、旋回半径の小さい状態で旋回中と誤判定し、また、旋回半径が小さいと誤判定していることから、旋回安定のための制動制御をするか否かの作動閾値が小さいことから、当該旋回安定のための制動制御のための自動的な制動が発生するおそれがある。
【００３３】
これに対し、本実施形態では、修正操舵が行われていると判断している場合には上記旋回安定制御手段による自動的な制動の発生を実施しないので、直進走行時や安定して旋回している走行状態において、運転者が意図しない減速度が発生することが防止される。
また、悪路走行中においては、微小な左右方向の舵の変更が繰り返し発生するなど、修正舵状態と非修正舵状態とが短い時間間隔で繰り返される場合があり、そのタイミングによっては、旋回安定のための制動制御のための自動的な制動が発生するおそれがある。これに鑑みて、本実施形態では、不感帯ＤＺ内に車両ＷＶが存在している場合には修正操舵中とみなして、上述のような問題を回避するようにしている。
【００３４】
一方、このような不感帯ＤＺを設けることは、運転者が旋回しようとしている操舵入力なのか修正操舵中なのかの判定をするまでに時間遅れが生じる場合がある。これに対し、本実施形態では、修正舵か否かの判定を悪路の場合に限定することで、良路走行時における旋回安定制御の制御介入遅れが生じることを防止することができる。なお、悪路か否かの判定を省略しても良い。
【００３５】
さらに、悪路の走行中であっても、その悪路の状態によって上記修正舵か否かを判定する作動閾値（修正舵と判定する境界）を変更、つまり悪路の場合ほど相対的に上記作動閾値を大きくするようにしているので、適切に修正舵か旋回のための操舵であるかを判断するとができる。
ここで、上記説明では、ステップＳ１８０〜ステップＳ２００の３ステップの３種類の判断によって修正舵か否かを判定しているが、このうちの１種類若しくは２種類の判断によって修正舵が否かを判定しても良い。
【００３６】
ステップＳ１８０の判断は、不感帯ＤＺを設けて修正舵を判断する方法であるが、この判断を採用すると、車両ＷＶが直進している場合の操舵入力を修正舵として除外できる効果と、前述のように、轍や悪路でステアリングホイールが取られた場合の修正舵などを効果的に検出することが可能となる。
例えば図６〜図８に示すように、舵角の向き（図中矢印で示されている）に関係なく、不感帯ＤＺ内に位置すれば修正操舵中と判断される。
【００３７】
また、ステップＳ１９０の判断は、例えば図９及び図１０に示されるように、直進目標軌跡に対する操舵角で修正舵を判断する方法であるが、この判断を採用すると、車両ＷＶが直進する方向に操舵入力している場合に直進のための修正舵として除外できる効果と、直進路での轍や悪路で挙動が乱れた場合に、進路を修正すべく与える修正舵を効果的に検出可能となる。
【００３８】
また、ステップＳ２００の判断は、図１１に示すように、直進目標軌跡に対する車両ＷＶのヨー角で修正舵の判断を行う方法であるが、車両ＷＶが直進を維持する方向に車両ＷＶのヨー角を向けている場合に直進のための修正舵を与えているとして除外できる効果と、車両ＷＶのヨー角は操舵角に比較して変動が小さく、直進か旋回意思があるかを安定して判別することができる。
【００３９】
そして、上記いずれにも該当しない図１２に示す状態の場合には、運転者の意思による旋回のための操舵入力として扱う。
本実施形態のタイムチャート例を図１３に示す。なお、図１３中の作動閾値は、仮想的に旋回安定制御手段で自動制動を発生するか否かの境界の閾値としたものである。この図１３から分かるように、悪路による修正操舵による旋回安定制御手段の誤動作が防止される。
【００４０】
ここで、修正舵は、上記判断方法に限定されず、操舵角速度や操舵トルクの変化率でも検出することができる。操舵角速度を使用した場合には、車両挙動の乱れにとっさに運転者が反応している場合が多く、修正操舵時の操舵角速度も大きい場合が多い。したがって、この操舵角速度による判断を入れることで、上記修正舵判断をより精度良く判断することが可能となる。また、操舵トルクの変化速度を考えた場合、修正操舵中では車両挙動の乱れに瞬間的に反応している場合が多く、パルス的な操舵トルク入力が入る場合が多い。したがって、操舵トルクの変化速度による判断を入れることによって、上記修正舵判断をより精度良く判断することが可能となる。なお、以上で５種類の修正舵の検出方法を例示しているが、この全てを必ずしも組み合わせる必要はなく、この５種類のうちの１種類だけ若しくは２種類以上を組み合わせて修正舵の検出を行っても良い。
【００４１】
また、悪路において旋回安定のための制動を行うと、良路の場合よりも車両挙動が乱れやすい場合があるため、悪路補正係数Ｋａに応じて前後輪の制動力配分を前輪よりにしても良い。
次に、本発明に基づく第２実施形態について図面を参照しつつ説明する。なお、上記第１実施形態と同様な処理や装置などについては同一の符号を付して説明する。
【００４２】
本第２実施形態の構成は、上記第１実施形態と同様であるが、
本実施形態の基本構成は上記第１実施形態と同様な構成であるが、上記コントローラ１４での処理のうちの本願発明に関わる制動制御処理の一部が異なる。
本第２実施形態の制動制御処理部の基本的な処理は、図１４に示すように、上記第１実施形態と同様であるが、ステップＳ２００とステップＳ２１０の処理の間にステップＳ４００の処理が挿入されると共に、修正操舵の検出を行うステップＳ１８０〜ステップＳ２００において、修正操舵と判定された場合（ｙｅｓの場合）にステップＳ２１０に移行して、修正操舵と判定しても旋回安定のための制動制御を実施するようにしている。すなわち、本第２実施形態は、修正操舵と判定した場合にも旋回安定のための制動制御を実施する場合の例である。
【００４３】
上述のように、旋回安定のための制動制御用の処理であるステップＳ２１０に対し、悪路であっても修正操舵中でないと判定した場合には、路面の状態を表す悪路補正係数Ｋａを１．０として移行し、修正操舵中と判定した場合にだけ、悪路補正係数Ｋａを、悪路に応じた値として移行する。
また、旋回安定のための制動制御用の処理（ステップＳ２１０〜ステップＳ３２０）のうち、制動を行うか否かの作動閾値の判定ステップであるＳ２５０ａと、目標減速度を演算するステップＳ２６０ａの処理が、第１実施形態と異なる。すなわち、修正操舵と判断された場合には、旋回安定のための自動減速制御の作動閾値を高く変更し（Ｓ２５０ａ）、且つ旋回安定のための自動減速制御の作動量（制御量）である目標減速度を小さく変更する（Ｓ２６０ａ）。
【００４４】
ステップＳ２５０ａにおいて、自動制動を負荷するか否かを判断するが、その際の作動閾値ｋＶL 、ｈＲL に対して（１／Ｋａ）を乗算して、修正操舵中と判定している場合には悪路であるほど上記作動閾値ｋＶL 、ｈＲL が大きくなるようにしている。
これは、悪路であるほど路面外乱によってステアリングホイールが取られ易く、旋回半径が小さい旋回走行状態で且つ旋回速度が大きいと誤判定されやすいためであり、上記のように作動閾値を大きくすることで、実際の旋回状態の作動閾値に近づけて、悪路での旋回走行中であっても、適正な旋回安定のための自動減速制御を行うようにするものである。
【００４５】
なお、上記路面状態による作動域の変更は、ステップＳ２５０で行う代わりに、限界車体速度ＶL 及び限界旋回半径ＲL についてステップＳ２３０及びＳ２４０にて上記悪路補正係数Ｋａによって補正するようにしても良い。
また、ステップＳ２６０ａにて、旋回時自動減速制御の作動量（制御量）である目標減速度を求める際に、上述のように、車体速度Ｖ、限界車体速度ＶL 、旋回半径Ｒ、限界旋回半径ＲL に基づき、目標減速度ＸＧＣＯを演算し、この目標減速度ＸＧＣＯに悪路補正係数Ｋａを乗算して、新たな目標限度速度とすることで、路面状況に応じて補正を加える。Ｋａは悪路であるほど小さい値をとるため、悪路であるほど目標減速度は小さく補正される。なお、限界車体速度ＶL 、限界旋回半径ＲL を悪路補正係数Ｋａで補正した場合には、ステップＳ２６０ａにて補正を加えなくても、悪路補正係数Ｋａで補正された目標減速度を求めることが可能である。
【００４６】
次に、本第２実施形態の作用・効果などについて説明すると、路面が良路である場合、および悪路であるものの運転者が旋回するために操舵していると判断された場合は、通常通りの旋回安定のための自動減速制御が行われ、路面が悪路で且つ修正操舵中であると判断された場合には、旋回安定のための自動減速制御介入閾値を高く変更し、且つ、制御量も小さく変更することで、実際の旋回状態に近い制動力で旋回安定のための自動減速制御を行うことが可能となる。
【００４７】
その他の作用・効果などは上記第１実施形態と同様である。
次に、本発明に基づく第３実施形態を図面を参照しつつ説明する。なお、上記各実施形態と同様な処理や装置については同一の符号を付して説明する。
上記第２実施形態では、路面状態に応じて、修正操舵中における旋回安定のための自動減速制御介入閾値、及び作動量（制御量）を補正する場合の例であるが、本第３実施形態は、検出した修正舵に応じて、上記修正操舵中における旋回安定のための自動減速制御介入閾値、及び作動量（制御量）を補正する場合の例である。
【００４８】
第３実施形態の基本構成は、上記第２実施形態と同様であるが、図１５に示すように、修正操舵中か判断するステップＳ１８０〜ステップＳ２００の３つの判断処理において、各ステップ毎に修正操舵中と判断した場合には、その修正操舵の度合い（修正操舵量）に応じて、個々に係数を求めるステップＳ１８４，Ｓ１９４，Ｓ２０４を設け、ステップＳ４００ａにて各係数を乗算して、修正操舵の状態に応じた係数Ｋａを求めるようにしている。その他の処理は、上記第２実施形態と同様である。
【００４９】
ここで、各修正操舵か否かの寄与率が判定方法が異なるため、その係数の求め方がそれぞれ異なる。また、図１５では、上記第２実施形態に合わせた処理フローで示しているが、各修正操舵か否かを判断することなく、つまり図１５におけるステップＳ１８０，Ｓ１８２、Ｓ１９０、Ｓ１９２，Ｓ２００，Ｓ２０２の処理を行うこと無く、常にステップＳ１８４，Ｓ１９４，及びステップＳ２０４を実施するようにしても良い。
【００５０】
なお、操舵角速度、及び操舵トルクの変化率によっても、修正操舵を判定する場合には、図１６に示すように、上記ステップＳ４００ａの代わりにステップＳ５００〜ステップＳ５２０の処理を追加すればよい。
本実施形態では、修正操舵量に応じて修正操舵中における旋回安定のための自動減速制御介入閾値、及び作動量（制御量）を適正と推定される値に補正可能となる。
その他の作用・効果などは上記実施形態と同様である。
【図面の簡単な説明】
【図１】本発明に基づく実施形態に係る構成を説明するブロック図である。
【図２】本発明に基づく実施形態に係る液圧系を説明する図である。
【図３】本発明に基づく第１実施形態に係る制御の処理フローを示す図である。
【図４】本発明に基づく第１実施形態に係る悪路補正係数を説明する図である。
【図５】本発明に基づく第１実施形態に係る推定走行軌跡及び直線目標軌跡を説明する図である。
【図６】本発明に基づく第１実施形態に係る不感帯による修正操舵検出を説明する図である。
【図７】本発明に基づく第１実施形態に係る不感帯による修正操舵検出を説明する図である。
【図８】本発明に基づく第１実施形態に係る不感帯による修正操舵検出を説明する図である。
【図９】本発明に基づく第１実施形態に係る操舵角による修正操舵検出を説明する図である。
【図１０】本発明に基づく第１実施形態に係る操舵角による修正操舵検出を説明する図である。
【図１１】本発明に基づく第１実施形態に係るヨー角による修正操舵検出を説明する図である。
【図１２】本発明に基づく第１実施形態に係る旋回のための操舵入力とみなされる例を説明する図である。
【図１３】本発明に基づく第１実施形態に係るタイムチャート例を示す図である。
【図１４】本発明に基づく第２実施形態に係る制御の処理フローを示す図である。
【図１５】本発明に基づく第３実施形態に係る制御の処理フローを示す図である。
【図１６】本発明に基づく第３実施形態に係る制御の別の処理フローを示す図である。
【符号の説明】
Ｋａ 悪路補正係数
ＴＤ 推定走行軌跡
ＴＬ 直進目標軌跡
ＣＰ 基準点
ＤＺ 不感帯
Ｂw 不感帯の幅
ＷＶ 車両[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a braking force control device for a vehicle that enables the vehicle to turn stably.
[0002]
[Prior art]
As a device that enables the vehicle to turn stably, for example, a traction control device and a vehicle skid prevention device (so-called VDC) are known. Both systems are aimed at stabilizing the vehicle. The former detects the driving slip and applies the braking force or suppresses the driving force, thereby securing the lateral force of the driving wheel and improving the stability. The latter aims to stabilize vehicle behavior by applying braking force to each wheel independently when the side slip angle or yaw rate of the vehicle deviates from a predetermined value.
[0003]
However, in situations where driving slip does not occur or in situations where the speed of the turning radius is exceeded, the above stabilization system does not operate until a so-called drift-out behavior or spin behavior is triggered. there were.
As a braking force control device for a vehicle corresponding to this problem, there is one described in Patent Document 1. This device detects a turning state amount of a vehicle, and when the turning state amount approaches a turning state amount set value with respect to a turning limit state amount at which the vehicle can stably run, the vehicle stably turns. The vehicle is provided with a turning stability control means for calculating a target deceleration required for maintaining and applying a braking force for realizing the target deceleration to the vehicle.
[0004]
[Patent Document 1]
Japanese Patent Publication No. 2600876
[0005]
[Problems to be solved by the invention]
Here, for example, if a change in the vehicle body behavior occurs so that the traveling direction of the vehicle is disturbed due to disturbance from the road surface due to traveling on a rough road, the driver suppresses the vehicle body behavior and moves toward the target traveling direction. The correct rudder is input so that the vehicle travels.
When the corrected rudder is input, the turning stability control means may detect the left / right acceleration or steering angle generated in the vehicle and erroneously determine the turning state. When the above-mentioned erroneous determination occurs, there is a problem that a braking force unintended by the driver is actually applied to the vehicle regardless of a straight traveling state or the like.
The present invention has been made by paying attention to the above-described problems, and in order to ensure unnecessary turning stability while automatically applying a predetermined braking force to ensure stable turning traveling. It is an object of the present invention to provide a vehicle braking force control device capable of preventing automatic braking force input.
[0006]
[Means for Solving the Problems]
  In order to solve the above-described problems, the present invention calculates a target deceleration necessary to maintain a stable turning of the vehicle when the vehicle approaches a limit turning state where the vehicle can stably travel, and calculates the target deceleration. In a vehicle braking force control device equipped with a turning stability control means for applying a corresponding braking force to a vehicle, correction steering is performed to eliminate unnecessary changes in vehicle behavior due to disturbances acting on the traveling vehicle body. When it is determined that the braking force is present, the braking force corresponding to the target deceleration is corrected to be small according to the corrected steering amount.
Further, a travel locus calculating means for calculating an estimated travel locus of the vehicle estimated from the past vehicle travel state, and a straight traveling for calculating a straight target trajectory when the vehicle goes straight from the estimated travel locus calculated by the travel locus calculating means. Target trajectory calculation means, and determines corrective steering based on the straight target trajectory.
[0007]
【The invention's effect】
According to the present invention, it is possible to prevent the vehicle body from being unnecessarily automatically braked by being erroneously recognized as turning by the correction rudder.
[0008]
DETAILED DESCRIPTION OF THE INVENTION
Next, embodiments according to the present invention will be described with reference to the drawings.
FIG. 1 is a block diagram showing the overall configuration of the present embodiment.
First, the configuration will be described. The wheel speeds of the front and rear wheels are detected by the respective wheel speed sensors 51, and the detection signals are output to the controller 14. In addition, an acceleration sensor 52 that detects the longitudinal and lateral acceleration of the vehicle, a steering angle sensor 53 that detects the steering angle of the steering wheel, a switch group 54 such as a brake switch, a pressure switch, and an accelerator switch, a yaw rate around the center of gravity of the vehicle And a hydraulic pressure sensor group 56 for detecting the hydraulic pressure of each wheel cylinder. The sensors and switches 51 to 56 output detection signals to the controller 14, respectively. The yaw rate sensor 55 and the hydraulic pressure sensor group 56 are used as necessary to improve control accuracy.
[0009]
The controller 14 performs arithmetic processing based on the various signals from the sensors and switches described above, and controls the brake actuator 16 that adjusts the brake pressure of each front and rear wheel, and the engine output adjuster 17 that adjusts the engine output. A control signal is output and controlled.
The brake actuator 16 includes a pressure switching valve 7 and pressure regulators 11, 21, 31, 41 arranged in the brake system of each wheel.
[0010]
A configuration example of the braking means will be described with reference to FIG. 2. Reference numeral 1 is a brake pedal, reference numeral 2 is a booster, reference numeral 3 is a reservoir, and reference numeral 4 is a master cylinder. Reference numerals 5 and 6 are plungers, reference numeral 7 is a switching valve, reference numeral 8 is an accumulator, reference numeral 9 is a pump, and reference numeral 15 is a reservoir. The reservoirs 3 and 15 may be the same. Reference numerals 10 and 30 are accumulators similar to the anti-skid accumulator, and reference numerals 20 and 40 are reservoir tanks similar to the anti-skid reservoir tank. Reference numerals 19 and 29 are pumps. Reference numerals 11, 21, 31, and 41 are solenoid valves, reference numerals 12, 22, 32, and 42 are calipers, and reference numerals 13, 23, 33, and 43 are disk rotors, each having four wheels. Reference numerals a1 to a4 are output signals from the wheel speed sensor 51 of each wheel, and are used for anti-skid and traction control. Symbol a5 is an output signal from the steering angle sensor 53, and symbols a6 and a7 are signals from the front and rear acceleration sensors 52a and 52b, respectively. In FIG. 2, the yaw rate sensor 55, the hydraulic pressure sensor 56 for each wheel, and various switch groups 54 are omitted. b is a control signal to the engine output regulator 17.
[0011]
Next, among the processes of the controller 14, the brake control process according to the present invention will be described with reference to FIG.
This braking control process is performed every predetermined sampling time. First, in step S10, the wheel speeds VFL, VFR, VRL, VRR of the four wheels are input, the steering angle θ is input in step S20, and in step S30. The accelerations DDX and DDY in the longitudinal direction and the lateral direction of the vehicle are input. In step S40, the vehicle body speed V is calculated from the wheel speeds VFL, VFR, VRL, VRR and the vehicle body longitudinal acceleration, and the process proceeds to step S50.
[0012]
In step S50, the yaw rate dφ of the vehicle is input, and in step S60, each wheel acceleration AFL, AFR, ARL, ARR is calculated based on the wheel speed input in step S10, and the process proceeds to step S70. These wheel accelerations AFL, AFR, ARL, and ARR indicate wheel speed fluctuations. If the road surface is a bad road, the wheel speed fluctuates. Can be determined.
[0013]
In step S70, the wheel acceleration frequencies fFL, fFR, fRL, and fRR obtained in S60 are calculated for each wheel, and in step S80, wheel acceleration fluctuation amplitudes BFL, BFR, BRL, and BRR are obtained. Subsequently, in step S90, an average value for a fixed time with respect to the frequencies fFL, fFR, fRL, and fRR calculated in step S70 is obtained for each wheel, and a maximum value fmax of the average values is obtained. Further, in step S100, the maximum value Bmax is calculated from the average value of the fluctuation amplitudes BFL, BFR, BRL, BRR for a certain time, and the process proceeds to step S110.
[0014]
In step S110, it is determined whether or not the calculated maximum frequency value fmax and maximum amplitude value Bmax are larger than certain set values f0 and B0. If at least one of fmax and Bmax is less than or equal to the set values f0 and B0, it is determined that the road surface is a good road, the process proceeds to S130, and the rough road correction coefficient Ka is set to 1, and the process proceeds to step S140. On the other hand, if both fmax and Bmax are larger than the set values f0 and B0, it is determined that the road surface is a rough road, and the routine proceeds to S120, where the rough road correction coefficient Ka corresponding to the product of fmax and Bmax is set, and step S140 is performed. Migrate to
[0015]
  Here, the relationship between the product of fmax and Bmax and the rough road correction coefficient Ka is determined, for example, as shown in FIG. Thereby, the rough road correction coefficient Ka is set to 1.0 in the case of a good road that is not a bad road, and is 0.2 to 1.0 in the case of a bad road. The smaller the value is, the closer it is to 1.0, and the greater the degree of the rough road is, the closer the value is to 0.2.
  Next, as a preparation for determining the correct rudder, an estimated travel locus TD of the vehicle WV is calculated based on the actual yaw rate dφ, the longitudinal and lateral accelerations DDX, DDY, and the vehicle body speed V of the vehicle WV, and is constant from the new one. Data relating to the estimated travel locus TD of the quantity is stored, and the process proceeds to step S150.
  Here, the calculation of the estimated travel locus TD is, for example, illustrated in FIG.5As described above, it is obtained from a past traveling locus point by circular approximation or linear approximation according to the situation of the traveling locus point group.
[0016]
In step S150, a point corresponding to the past for a predetermined time from the present on the calculated estimated travel locus TD is set as a reference point CP, and a straight target trajectory is calculated assuming that the vehicle WV goes straight after the reference point CP. That is, the tangent line of the estimated traveling locus TD at the reference point CP position is obtained as the straight traveling target locus. Further, after setting the dead zone DZ regions (see FIG. 6) each having a width Bw on both sides of the straight advance target locus, the process proceeds to step S160.
[0017]
Here, the determination of the reference point CP is, for example, a point on the estimated traveling locus TD corresponding to the past for several cycles of control as the reference point CP, or a point on the estimated traveling locus TD a predetermined time before the present. As a reference point CP. Note that the calculation of the position of the reference point CP may be changed according to the vehicle body speed, the curvature of the estimated travel locus TD, or the like.
[0018]
Further, the dimension of the width Bw of the dead zone DZ may be determined by, for example, obtaining the amount of behavior of the vehicle body in the left-right direction when traveling on a rough road from experiments and empirical values, and adding a margin to it. The width Bw of the dead zone DZ of the present embodiment is such that the larger the vehicle body speed V, the greater the acceleration DDY in the lateral direction of the vehicle body, and the smaller the rough road correction coefficient Ka indicating the road surface condition such as a bad road (bad road). The setting is changed to increase the width.
For example,
[0019]
[Expression 1]

[0020]
It is. However, a, b, c, d, and e are constants.
In step S160, the yaw angle φ of the vehicle WV based on the target straight line locus is calculated from the actual yaw rate dφ, the longitudinal and lateral accelerations DDX and DDY of the vehicle WV, and the vehicle body speed V, and the process proceeds to step S170. .
In step S170, the rough road is determined based on the rough road correction coefficient Ka corresponding to the road surface condition. When the road is rough, that is, when Ka <1.0, the process proceeds to step S180 to determine the correction rudder. Proceeding to the step, if it is not a rough road, that is, if Ka = 1.0, the correction rudder determination is not executed and the routine proceeds to step S210.
[0021]
In step S180, it is determined whether or not the vehicle WV is in the dead zone DZ. When the vehicle WV deviates from the dead zone DZ, the process proceeds to step S190, and when it is determined that the vehicle WV is located within the dead zone DZ, the vehicle WV returns without operating the automatic deceleration control for stabilizing the turn.
In step S190, it is determined whether or not the vehicle is steered in a direction to return to the straight target locus. If it is determined that the vehicle is steered in a direction away from the straight target locus, the process proceeds to S200 and returns to the straight target locus. When it is determined that the vehicle is steered in the direction, it is determined that the corrected rudder is being provided, and the vehicle returns without operating the automatic deceleration control for turning stability.
[0022]
In step S200, it is determined whether or not the yaw angle φ of the vehicle WV is away from the straight target trajectory. In the case of the direction returning to the straight target trajectory, it is determined that the correction steering for correcting the course is being performed, and the vehicle returns without operating the automatic deceleration control for turning stability. On the other hand, when it is determined that the yaw angle φ of the vehicle WV is away from the straight target locus, the process proceeds to step S210 in order to perform automatic deceleration control for turning stability.
[0023]
Here, as the above-described determination of the correction rudder, a step of determining that the correction rudder is corrected as the absolute value of the change amount of the steering angular velocity, the steering angular acceleration, and the steering torque increases may be added.
In step S210, the slip ratios SFL, SFR, SRL, and SRR of each wheel are obtained from each wheel speed and vehicle body speed V. In step S220, the turning radius R is calculated based on the following equation from the vehicle body speed V and the vehicle body lateral acceleration DDY, and the process proceeds to step S230.
[0024]
R = (V²/ DDY)
In step S230, the limit turning radius RL at the current vehicle speed V is obtained from the vehicle speed V. For example, if the limit vehicle body lateral acceleration determined by the vehicle WV is DDY1, RL = (V²/ DDY1).
Subsequently, in step S240, the limit turning speed VL at the current turning radius R is obtained from the turning radius R based on the following equation, and the process proceeds to step S250.
[0025]
VL = √ (R · DDY1)
Here, the limit vehicle body lateral acceleration DDY1 may be changed according to the slip ratios SFL, SFR, SRL, and SRR of each wheel. Further, depending on the slip ratios SFL, SFR, SRL, and SRR of each wheel, priority may be given to anti-skid or traction control.
[0026]
In step S250, it is determined what value the turning radius R is with respect to the limit turning radius RL or the vehicle body speed V is with respect to the limit turning vehicle speed VL, and allowable values kVL and hRL (however, k) which are operating threshold values. , H <1), that is, when the vehicle body speed V is larger than the allowable value kVL or the turning radius R is smaller than the allowable value hRL, the brake control process should be performed. The process proceeds to step S260, and if the allowable value is not exceeded, the process is terminated and returned. Here, the coefficients k and h (k and h are coefficients slightly smaller than 1) of the allowable values kVL and hRL are determined in advance.
[0027]
In step S260, the target deceleration XGCO is calculated based on the vehicle body speed V, the limit vehicle body speed VL, the turning radius R, and the limit turning radius RL, and the process proceeds to step S270.
In step S270, the target brake fluid pressures of the front and rear wheels for obtaining the target deceleration XGCO are obtained, and the process proceeds to step S280.
In step S280, the pressure switching valve 7 is turned on (the state on the right side of FIG. 3). As a result, the hydraulic pressure in the accumulator acts on the plunger, and the pressurized fluid in the plunger is sent to the pressure regulators 11, 21, 31, 41 side.
[0028]
In step S290, the supply currents iFL, iFR, iRL, iRR to the solenoids of the pressure regulators 11, 21, 31, 41 necessary for obtaining the target brake fluid pressure distributed to each wheel are obtained, and the process proceeds to step S300. Then, a deceleration of the vehicle WV is obtained by supplying a current to each solenoid and performing a brake pressure control. That is, with respect to the pressure regulators 11, 21, 31, and 41, when the valve position is set to the left position in FIG. 2, the pressure fluid is sent from the plungers 5 and 6 to the calipers 12, 22, 32, and 42 of the brake, The brake fluid pressure is increased. When the valve position is in the neutral position, the brake fluid pressure is kept constant by blocking the fluid passage. On the other hand, when the valve position is on the right side, the brake fluid is returned to the reservoir tanks 20 and 40 side. Thus, the brake pressure of each wheel is controlled by controlling the switching position of the pressure regulators 11, 21, 31, 41. The pressurized liquid in the reservoir tanks 20 and 40 is returned to the reservoir tank 3 by the pumps 19 and 29.
[0029]
On the other hand, in step S310, an engine output control signal for obtaining the target deceleration XGCO is calculated. For example, when the engine output is controlled by the throttle opening, the target throttle opening is determined in consideration of the relationship with the deceleration obtained by the brake, and a control signal for obtaining the target throttle opening is calculated. Subsequently, in step S320, the engine output regulator is driven. In the above example, the throttle is driven.
[0030]
Here, steps S210 to S320 constitute a turning determination control means, each process of S180 to S200 constitutes a modified rudder detection means, step S140 constitutes a travel locus calculation means, and step S150 constitutes a straight target locus calculation means.
Next, the operation, action, and effect of the above configuration will be described.
If the vehicle WV approaches the limit at which the vehicle WV can turn stably when the vehicle WV is turning, the vehicle WV is actively decelerated, and the vehicle WV does not exceed the limit at which the vehicle WV can stably turn regardless of the driver's will. Thus, the braking is controlled.
[0031]
Here, when driving straight ahead, when driving on so-called bad roads such as roads with lots of bumps and irregularities, disturbances from the road surface cause unintended vehicle behavior due to lateral forces acting on the wheels. In order to cope with this, the driver performs correction steering in order to return the traveling direction of the vehicle WV to the intended traveling direction. In addition, unplanned vehicle behavior occurs due to disturbances such as crosswinds, and the driver performs a correction operation.
[0032]
In the above-described correction steering, since the steering angular speed is usually large or the required lateral acceleration is generated in the vehicle body, the turning stability control means erroneously determines that the turning is in a state where the turning radius is small, and if the turning radius is small Since an erroneous determination is made, the operation threshold value for determining whether or not to perform braking control for turning stability is small, and therefore, automatic braking for braking control for turning stabilization may occur.
[0033]
On the other hand, in the present embodiment, when it is determined that the correction steering is performed, the automatic braking is not generated by the above-mentioned turning stability control means. It is possible to prevent a deceleration unintended by the driver from occurring in the running state.
Also, during rough road driving, the correct rudder state and uncorrected rudder state may be repeated at short time intervals, such as minute changes in the rudder in the left and right direction. There is a possibility that automatic braking for braking control for the vehicle occurs. In view of this, in the present embodiment, when the vehicle WV is present in the dead zone DZ, it is considered that correction steering is being performed, and the above-described problem is avoided.
[0034]
On the other hand, providing such a dead zone DZ may cause a time delay until it is determined whether the driver is making a steering input or during a corrective steering. On the other hand, in this embodiment, it is possible to prevent a delay in the control intervention of the turning stability control when traveling on a good road by limiting the determination of whether or not the steering is a correct road to a rough road. In addition, you may abbreviate | omit the determination whether it is a bad road.
[0035]
Furthermore, even when the vehicle is traveling on a rough road, the operating threshold value (boundary to be determined as a corrected rudder) is changed depending on the state of the rough road. Since the operation threshold value is increased, it is possible to appropriately determine whether the steering is for correction or turning.
Here, in the above description, whether or not the correction rudder is determined is determined by three types of determinations of three steps from Step S180 to Step S200, but whether or not the correction rudder is determined by one or two types of determinations. You may judge.
[0036]
The determination in step S180 is a method of determining the correction rudder by providing the dead zone DZ. If this determination is adopted, the steering input when the vehicle WV is traveling straight can be excluded as the correction rudder, as described above. In addition, it is possible to effectively detect a correction rudder or the like when the steering wheel is taken on a saddle or a rough road.
For example, as shown in FIGS. 6 to 8, it is determined that the correction steering is in progress if the vehicle is positioned within the dead zone DZ regardless of the direction of the steering angle (indicated by an arrow in the figure).
[0037]
Further, for example, as shown in FIGS. 9 and 10, the determination in step S190 is a method of determining the correction rudder based on the steering angle with respect to the straight traveling target trajectory. If this determination is employed, the vehicle WV moves in a straight direction. The effect that can be excluded as a correction rudder for straight running when steering is input, and the correction rudder that is given to correct the course can be detected effectively when the behavior is disturbed on the dredging or bad road on the straight road Become.
[0038]
Further, as shown in FIG. 11, the determination in step S200 is a method of determining the correction rudder based on the yaw angle of the vehicle WV with respect to the straight target trajectory. The effect that can be ruled out by giving a correction rudder for going straight, and the yaw angle of the vehicle WV are less variable than the steering angle, and it is possible to determine whether the vehicle is going straight or turning can do.
[0039]
In the case of the state shown in FIG. 12 that does not correspond to any of the above, it is handled as a steering input for turning by the driver's intention.
An example of a time chart of this embodiment is shown in FIG. Note that the operation threshold value in FIG. 13 is a threshold value that virtually determines whether or not automatic braking is generated by the turning stability control means. As can be seen from FIG. 13, malfunction of the turning stability control means due to the correction steering on the rough road is prevented.
[0040]
Here, the correction rudder is not limited to the above-described determination method, and can be detected by the change rate of the steering angular velocity and the steering torque. When the steering angular velocity is used, the driver often reacts to the disturbance of the vehicle behavior in many cases, and the steering angular velocity during the correction steering is often large. Therefore, by making a determination based on the steering angular velocity, the correction rudder determination can be determined with higher accuracy. Further, when considering the change speed of the steering torque, there are many cases of instantaneous response to disturbance of the vehicle behavior during the correction steering, and there are many cases where pulsed steering torque input is input. Therefore, by making a determination based on the change speed of the steering torque, the correction rudder determination can be determined with higher accuracy. In addition, although the detection method of five types of correction rudder is illustrated above, it is not always necessary to combine all of these, and correction rudder detection is performed by combining only one of these five types or two or more types. May be.
[0041]
In addition, when braking is performed on a rough road to stabilize turning, the vehicle behavior may be disturbed more easily than on a good road, so the braking force distribution of the front and rear wheels is set to be more than that of the front wheels according to the rough road correction coefficient Ka. Also good.
Next, a second embodiment according to the present invention will be described with reference to the drawings. In addition, the same code | symbol is attached | subjected and demonstrated about the process similar to the said 1st Embodiment, an apparatus, etc. FIG.
[0042]
The configuration of the second embodiment is the same as that of the first embodiment,
The basic configuration of this embodiment is the same as that of the first embodiment, but a part of the braking control processing related to the present invention in the processing in the controller 14 is different.
As shown in FIG. 14, the basic process of the braking control processing unit of the second embodiment is the same as that of the first embodiment, but the process of step S400 is performed between the processes of step S200 and step S210. In step S180 to step S200, in which the correction steering is detected, the process proceeds to step S210 when it is determined that the correction steering is detected (in the case of yes). Braking control is performed. That is, this 2nd Embodiment is an example in the case of implementing braking control for turning stability, even when it judges with correction steering.
[0043]
As described above, when it is determined that correction steering is not being performed even on a bad road, the rough road correction coefficient Ka representing the road surface condition is set in step S210 which is a process for braking control for turning stability. Only when it is determined that the correction steering is in progress, the rough road correction coefficient Ka is shifted as a value corresponding to the rough road.
Of the brake control processes for stabilizing the turn (steps S210 to S320), the process of S250a, which is a determination step for determining whether or not to perform braking, and the process of step S260a for calculating the target deceleration are performed. This is different from the first embodiment. That is, when it is determined that the steering is corrected, the threshold value of the automatic deceleration control for stabilizing the turn is changed to a higher value (S250a), and the target is the operation amount (control amount) of the automatic deceleration control for stabilizing the turn. Deceleration is changed to a smaller value (S260a).
[0044]
In step S250a, it is determined whether or not automatic braking is to be applied. If the operation threshold values kVL and hRL at that time are multiplied by (1 / Ka) and it is determined that the correction steering is being performed, it is bad. The operation threshold values kVL and hRL are increased as the path is increased.
This is because the worse the road, the easier the steering wheel is taken due to road disturbance, and it is easy to misjudge that the turning radius is small and the turning speed is high, and the operating threshold is increased as described above. Thus, the automatic deceleration control for proper turning stability is performed even when turning on a rough road by approaching the operation threshold value of the actual turning state.
[0045]
It should be noted that the change of the operation range depending on the road surface condition may be corrected by the rough road correction coefficient Ka in steps S230 and S240 for the limit vehicle body speed VL and the limit turning radius RL instead of being performed in step S250.
Further, in step S260a, when obtaining the target deceleration which is the operation amount (control amount) of the automatic deceleration control during turning, as described above, the vehicle speed V, the limit vehicle speed VL, the turn radius R, the limit turn radius, as described above. Based on R L, the target deceleration XGCO is calculated, and the target deceleration XGCO is multiplied by a rough road correction coefficient Ka to obtain a new target limit speed, thereby correcting according to the road surface condition. Since Ka takes a smaller value as the road becomes worse, the target deceleration is corrected to be smaller as the road becomes worse. When the limit vehicle body speed VL and the limit turning radius RL are corrected with the rough road correction coefficient Ka, the target deceleration corrected with the rough road correction coefficient Ka is obtained without correction in step S260a. Is possible.
[0046]
Next, the operation and effect of the second embodiment will be described. When the road surface is a good road, and when it is determined that the driver is steering to turn although it is a bad road, Automatic deceleration control for stabilizing the turning of the street is performed, and when it is determined that the road surface is a rough road and the correction steering is in progress, the automatic deceleration control intervention threshold value for stabilizing the turning is changed high, and By changing the control amount to be small, it is possible to perform automatic deceleration control for stabilizing the turn with a braking force close to the actual turning state.
[0047]
Other operations and effects are the same as those in the first embodiment.
Next, a third embodiment according to the present invention will be described with reference to the drawings. In addition, the same code | symbol is attached | subjected and demonstrated about the process and apparatus similar to said each embodiment.
The second embodiment is an example of correcting the automatic deceleration control intervention threshold for turning stability during the correction steering and the operation amount (control amount) according to the road surface state, but the third embodiment. These are examples in the case where the automatic deceleration control intervention threshold value for turning stability during the correction steering and the operation amount (control amount) are corrected in accordance with the detected correction rudder.
[0048]
The basic configuration of the third embodiment is the same as that of the second embodiment. However, as shown in FIG. 15, in the three determination processes of step S180 to step S200 for determining whether correction steering is in progress, correction is performed for each step. If it is determined that the steering is in progress, steps S184, S194, and S204 for individually obtaining coefficients are provided in accordance with the degree of the corrected steering (corrected steering amount), and each coefficient is multiplied in step S400a to correct the steering. The coefficient Ka corresponding to the state is determined. Other processes are the same as those in the second embodiment.
[0049]
Here, since the determination method of the contribution ratio of whether each correction steering is different, the method of obtaining the coefficient is different. Further, in FIG. 15, a processing flow according to the second embodiment is shown, but it is not determined whether or not each correction steering is performed, that is, steps S180, S182, S190, S192, S200, and S202 in FIG. The steps S184, S194, and step S204 may always be performed without performing the process.
[0050]
In addition, when the correction steering is determined also by the steering angular velocity and the change rate of the steering torque, the processes of steps S500 to S520 may be added instead of step S400a as shown in FIG.
In the present embodiment, the automatic deceleration control intervention threshold for stabilizing the turn during the correction steering and the operation amount (control amount) can be corrected to values estimated to be appropriate according to the correction steering amount.
Other actions and effects are the same as in the above embodiment.
[Brief description of the drawings]
FIG. 1 is a block diagram illustrating a configuration according to an embodiment of the present invention.
FIG. 2 is a diagram illustrating a hydraulic system according to an embodiment of the present invention.
FIG. 3 is a diagram showing a control processing flow according to the first embodiment of the present invention.
FIG. 4 is a diagram illustrating a rough road correction coefficient according to the first embodiment based on the present invention.
FIG. 5 is a diagram illustrating an estimated traveling locus and a straight target locus according to the first embodiment based on the present invention.
FIG. 6 is a diagram for explaining correction steering detection using a dead zone according to the first embodiment of the present invention.
FIG. 7 is a diagram for explaining correction steering detection using a dead zone according to the first embodiment of the present invention.
FIG. 8 is a diagram for explaining correction steering detection by a dead zone according to the first embodiment of the present invention.
FIG. 9 is a diagram illustrating correction steering detection based on a steering angle according to the first embodiment of the present invention.
FIG. 10 is a diagram illustrating correction steering detection based on a steering angle according to the first embodiment of the present invention.
FIG. 11 is a diagram illustrating correction steering detection based on yaw angle according to the first embodiment of the present invention.
FIG. 12 is a diagram illustrating an example that is regarded as a steering input for a turn according to the first embodiment of the present invention.
FIG. 13 is a diagram showing an example time chart according to the first embodiment of the present invention.
FIG. 14 is a diagram showing a processing flow of control according to a second embodiment based on the present invention.
FIG. 15 is a diagram showing a processing flow of control according to a third embodiment based on the present invention.
FIG. 16 is a diagram showing another processing flow of control according to the third embodiment of the present invention.
[Explanation of symbols]
Ka rough road correction coefficient
TD Estimated travel trajectory
TL Straight target trajectory
CP reference point
DZ dead zone
Bw Deadband width
WV vehicle

Claims (9)

Turning to determine that the vehicle is approaching a limit turning state in which the vehicle can stably travel and to calculate a target deceleration necessary to maintain a stable turning of the vehicle and to apply a braking force corresponding to the target deceleration to the vehicle In the vehicle braking force control device including the stability control means,
A correction rudder detection means for detecting a correction steering for eliminating a change in vehicle body behavior due to a disturbance acting on a traveling vehicle;
When it is determined that the correction steering is performed based on the detection of the correction rudder detection unit, the turning stability control unit corrects the braking force according to the target deceleration to be small according to the correction steering amount ,
The modified rudder detection means includes
Traveling trajectory calculating means for calculating an estimated traveling trajectory of the vehicle estimated from past vehicle traveling conditions, and a straight traveling target trajectory for calculating a straight traveling target trajectory when the vehicle goes straight from the estimated traveling trajectory calculated by the traveling trajectory calculating means A vehicle having a dead zone with a predetermined width on both sides of the straight target trajectory, and determining that the current vehicle is located within the dead zone and determining that correction steering is in progress Braking force control device. Turning to determine that the vehicle is approaching a limit turning state in which the vehicle can stably travel and to calculate a target deceleration necessary to maintain a stable turning of the vehicle and to apply a braking force corresponding to the target deceleration to the vehicle In the vehicle braking force control device including the stability control means,
A correction rudder detection means for detecting a correction steering for eliminating a change in vehicle body behavior due to a disturbance acting on a traveling vehicle;
When it is determined that the correction steering is performed based on the detection of the correction rudder detection unit, the turning stability control unit corrects the braking force according to the target deceleration to be small according to the correction steering amount,
The modified rudder detection means includes
Traveling trajectory calculating means for calculating an estimated traveling trajectory of the vehicle estimated from past vehicle traveling conditions, and a straight traveling target trajectory for calculating a straight traveling target trajectory when the vehicle goes straight from the estimated traveling trajectory calculated by the traveling trajectory calculating means comprising calculating means, the current yaw angle the straight target trajectory side opposite to that with the determined vehicles of the braking force control device shall be the determining means determines that is being modified steering when the vehicle . Turning to determine that the vehicle is approaching a limit turning state in which the vehicle can stably travel and to calculate a target deceleration necessary to maintain a stable turning of the vehicle and to apply a braking force corresponding to the target deceleration to the vehicle In the vehicle braking force control device including the stability control means,
A correction rudder detection means for detecting a correction steering for eliminating a change in vehicle body behavior due to a disturbance acting on a traveling vehicle;
When it is determined that the correction steering is performed based on the detection of the correction rudder detection unit, the turning stability control unit corrects the braking force according to the target deceleration to be small according to the correction steering amount,
The modified rudder detection means includes
Traveling trajectory calculating means for calculating an estimated traveling trajectory of the vehicle estimated from past vehicle motion states, and a straight traveling target trajectory for calculating a straight traveling target trajectory when the vehicle goes straight from the estimated traveling trajectory calculated by the traveling trajectory calculating means. comprising calculating means, and the current modification steering direction of both car you and judging to be in corrective steering in the case where it is determined that faces in a direction to return the vehicle to the straight target trajectory Braking force control device. The vehicle according to any one of claims 1 to 3 , wherein the correction rudder detection means determines that the correction steering is being performed when the amount of change in the rudder angle per unit time is equal to or greater than a predetermined value. Braking force control device. The said correction rudder detection means determines with the correction | amendment steering being in progress, when the steering torque variation | change_quantity per unit time is more than predetermined value, The description in any one of Claims 1-4 characterized by the above-mentioned. Vehicle braking force control device. Provided with a rough road determination means for detecting the state of the running road surface,
The vehicle according to any one of claims 1 to 5 , wherein the correction rudder detection means detects correction steering only when it is determined that the road is a bad road based on the detection by the bad road determination means. Braking force control device. 7. The vehicle braking force control device according to claim 6 , wherein the correction rudder detection means changes a threshold value for determining the correction steering in accordance with the degree of the rough road based on the detection by the bad road determination means. The cornering stability control section, wherein the braking force corresponding to the target deceleration, according to the degree of bad road which based on the detection of bad road judging means to claim 6 or claim 7, characterized in that to reduce the correction Vehicle braking force control device. The turning stability control means corrects an operation threshold value for determining whether or not the vehicle is in a limit turning state where the vehicle can stably travel according to the degree of a bad road based on the detection of the bad road determination means. The vehicle braking force control device according to any one of claims 6 to 8 , wherein the vehicle braking force control device is a vehicle braking force control device.

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