JP2004287672A - Recommended manipulation variable generating device for vehicle - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a recommended manipulation variable generating device for a vehicle for realizing the merging of a vehicle whose sense of incongruity is small for a driver. <P>SOLUTION: This device is provided with its own vehicle condition detecting means 2, a surrounding vehicle detecting means 1, a traffic lane detecting means 6, a merging detecting means 5 for detecting the merging terminal of a traffic lane, a means 3a for predicting the future location and speed of each vehicle and an evaluating means 3b for numerically evaluating the ideal condition of the whole vehicle group. Furthermore, this device is provided with a recommended manipulation variable calculating means 3d for calculating the accelerating/decelerating manipulation recommended for its own vehicle 10 and a surrounding vehicle 11 and the pattern of the traffic lane changing manipulation based on the future prediction of the evaluation value calculated by the evaluating means 3b and an operation policy decision means 3c for deciding whether the merging vehicle 10 should merge ahead or behind the main traffic lane vehicle 11 from the relationship of the positions and speeds of a merging vehicle 10 traveling on a merging traffic lane 13 whose lane disappearance is detected and the main traffic lane vehicle 11 traveling on a main traffic lane 12 adjacent to the merging traffic lane 13. Then, the evaluating means 3b is corrected according to the calculation results of the operation policy decision means 3c. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

【００１２】
【数２】

ここで、ｕ_ｘ ^Ｔ、ｕ_ｘ ^Ｍは、それぞれ本線車両１１、合流車両１０の加減速指令値、ｕ_ｙ ^Ｍは合流車両１０の車線変更に関する指令値であり、ここでは変数ｙ_Ｍに対する指令値として定義される。すなわち、合流車線１３に留まる場合に−１、本線車線１２に合流する場合に１という値を取る。ωは適当な正の定数であり、指令値ｕ_ｙ ^Ｍの値が−１から１へとステップ的に変化した場合に、変数ｙ_Ｍが−１から１へと遷移するのにかかる時間と、現実の車線変更動作において車線変更を開始してから完了するまでにかかる時間とがおおよそ等しくなるような値に設定される。以上の微分方程式により、本線車両１１および合流車両１０の操作を表すｕ_ｘ ^Ｔ、ｕ_ｘ ^Ｍ、ｕ_ｙ ^Ｍの時系列パターンと、各変数の初期値を与えると、そのような操作に対応して本線車両１１と合流車両１０がどのように動いていくかを計算することができる。各変数の初期値は測定された周囲環境情報３ｆによって与えられる。以上が予測手段３ａの処理内容である。
なお、「・」は時間微分を表し、括弧（ ）付きの数式においては「・」は変数の上にあるものとし、上付きの「・」と、変数の上にある「・」は同意とする。
【００１３】
評価手段３ｂは、本線車両１１と合流車両１０が実行する操作、およびそのような操作を取った場合に予想される未来の周囲環境の望ましさを、適当な基準を導入することによって数値的に評価するブロックである。具体的には、例えば、以下のような評価関数を定義することで評価を行なうことができる。
【００１４】
【数３】

ただし、ｘ（τ）＝（ｘ_Ｔ（τ）ｖ_Ｔ（τ）ｘ_Ｍ（τ）ｖ_Ｍ（τ）ｙ_Ｍ（τ））^Ｔ、ｕ（τ）＝（ｕ_ｘ ^Ｔ（τ）ｕ_ｘ ^Ｍ（τ）ｕ_ｙ ^Ｍ（τ））^Ｔであり、ｔは現実に経過している時間を表す変数、τは予測計算を行なう際に時間を表す変数、Ｔは予測時間の長さを表す定数である。評価関数Ｌは時刻τにおける車群の状態ｘおよび操作量ｕの望ましさを適当な基準のもとに数値的に測る関数であり、ここではその値が小さいほど望ましい状態である関数として定義する。同様に、評価関数ψは予測の終端時刻における車群の状態ｘの望ましさを測る関数である。
（３）式は、時刻ｔにおいて入力ｕ（τ）、ｔ≦τ≦ｔ＋Ｔを加えた場合に予想される評価を表している。このような評価を導入することで、本線車両１１および合流車両１０がどのような操作を行なえば適切な合流挙動を実現できるのかを評価することが可能になる。そこで、（３）式の評価ができるだけ良くなるような操作を制御指令として運転者に提示すれば、合流場面における運転を支援することができる。
評価関数Ｌは望ましい運転に対する要請を表現したいくつかの関数から構成され、各関数の線形加重和を取ることによって一つの関数としてまとめられる。具体的な関数の構成方法の一例を以下に示す。
一つ目の要請として、加減速の操作がなるべく小さいという要請を考えることができる。これは、大きな加減速は運転者や乗員に不快感や違和感を与える恐れがある、ということを考慮した要請である。このような要請を表現する関数として、次のような関数を導入する。
【００１５】
【数４】

二つ目の要請として、頻繁に車線変更を行なわないという要請を考えることができる。これは、本線車線１２に合流することを指令した後に再度合流車線１３に戻るような指令が算出されることを防ぐ目的がある。具体的には、
【００１６】
【数５】

という関数で表現される。
三つ目の要請として、なるべく各車１０、１１の希望走行車速に近い速度で走行を続ける、という要請を考えることができる。この要請も、希望走行車速と大きく離れた速度での走行を強いられることは、運転者に不快感や違和感を与える恐れがあることに対応したものである。具体的には、
【００１７】
【数６】

という関数で表現される。ここで、ｖ_Ｔ ^＊、ｖ_Ｍ ^＊はそれぞれ本線車両１１と合流車両１０の希望走行車速（目標車速）を表すパラメータである。
四つ目の要請として、合流車両１０が合流車線１３にいる場合には合流終端ｘ_ｅｎｄに近づき過ぎず、本線車線１２にいる場合には本線車両１１に近づき過ぎない、という要請を考えることができる。これは、余裕のある合流を実現するための基本的な要請である。ここでは、合流終端ｘ_ｅｎｄに近づき過ぎないという要請を、合流車両１０が合流車線１３に留まることに対するリスクとして表現し、合流車両１０が本線車両１１に近づき過ぎないという要請は、両車１０、１１の縦方向の位置と速度の関係から定義されるリスクによって表現する。合流車線１３に留まることに関するリスクを表現する関数として、ＭＰ（ｘ_Ｍ）を導入する。具体的な関数形として、例えば図４に示すような関数を考えることができる。図４において、ＭＰ_ｍｉｎ、ＭＰ_ｍａｘはそれぞれリスク関数の最小値と最大値、αは０から１までの値を取る定数である。図４に示すように、合流終端ｘ_ｅｎｄに向けてリスクの値を上げることによって、合流終端ｘ_ｅｎｄの付近では本線車線１２へ車線変更することをより重視する制御指令が算出されることが期待できる。
本線車両１１と合流車両１０との間のリスクについては、ここでは車間時間（車間距離／追従車両速度）と衝突時間（車間距離／相対速度）の逆数で評価するものとする。具体的なリスク関数として、
【００１８】
【数７】

【００１９】
【数８】

を導入する。ただし、βは０から１までの値を取る定数である。以上で導入した合流車線１３に留まることに対するリスク関数ＭＰ（ｘ_Ｍ）と、本線車線１２に車線変更することに対するリスク関数ＲＰ（ｘ_Ｔ，ｖ_Ｔ，ｘ_Ｍ，ｖ_Ｍ）を合流車両１０の走行車線の位置によって切り替わるような構成としたものが、四つ目の要請の表現関数となる。すなわち、
【００２０】
【数９】

のような表現関数を構成することができる。ここで、関数ｃは、ｃ（−１）＝０、ｃ（１）＝１を満たす連続関数であり、例えば、
【００２１】
【数１０】

のような関数を用いることができる。
以上の各評価項の線形加重和によって、全体の評価を表す評価関数Ｌが次式のように構成される。
【００２２】
【数１１】

一方、関数ψは必ずしも定義する必要はない。後で説明する運転方針決定手段３ｃの計算結果を評価に反映する手段の一つとして利用することができるので、運転方針決定手段３ｃの説明の部分で改めて例を示す。
以上が評価手段３ｂの構成例である。
【００２３】
予測手段３ａに関する（１）、（２）式と、評価手段３ｂに関する（３）、（１１）式が定義されると、（３）式の評価関数を最小とするようなｕを求めるという最適制御問題を定義することができる。最適制御問題を解いて得られた解は、評価関数が適切に設計されていれば、適切な合流挙動を再現する操作量になっていると期待できる。従って、算出された操作量を運転者に提示することで、合流挙動のアシストが実現できる。自車１０以外の車両については、必ずしも最適制御問題の解として得られた操作と同じ操作をするとは限らないが、評価関数が適切に設計されていれば、得られた操作は標準的な運転者が取ると予想される運転操作の良い予測になっていることが期待できる。また、仮に予測が外れた場合でも、最適解の更新を随時行なっていく構成とすれば、予測が外れた時点で新たな予測に基づく解が計算されるので、新たな状況に対応した操作量を提示することができる。
最適制御問題の系統的な解法はよく研究されており（例えば、文献１：加藤寛一郎著 工学的最適制御 非線形へのアプローチ、文献２：Ｔ． Ｏｈｔｓｕｋａ， “Ｃｏｎｔｉｎｕａｔｉｏｎ／ＧＭＲＥＳ ｍｅｔｈｏｄ ｆｏｒ ｆａｓｔ ａｌｇｏｒｉｔｈｍ ｏｆ ｎｏｎｌｉｎｅａｒ ｒｅｃｅｄｉｎｇ ｈｏｒｉｚｏｎ ｃｏｎｔｒｏｌ” Ｐｒｏｃ． ３９ｔｈ ＩＥＥＥ Ｃｏｎｆｅｒｅｎｃｅ ｏｎ Ｄｅｃｉｓｉｏｎ ａｎｄ Ｃｏｎｔｒｏｌ， ｐｐ．７６６−７７１， ２０００． など）、効率的に解を計算する手法が数多く提案されている。推奨操作量算出手段３ｄはそのような計算を実行することによって、実際に推奨操作量を算出する処理を行なうブロックである。
最適制御問題の解として得られる操作量は、評価手段３ｂの中に取り入れる評価項の設計次第によって、従来技術では十分に考慮されていなかった運転者の不快感や違和感を効果的に抑制することが期待できる。しかし、合流場面において運転者にとってより重要な情報は、本線車両１１の前方に合流すればよいのか、後方に合流すればよいのか、を直接的に指示する情報であると思われる。評価手段３ｂを構成する各関数には、こうした判断を直接的に表現する要素は存在せず、最適化計算を行なってみて初めて前方に合流すべきか後方に合流すべきかがわかるという構成である。しかし、そのような構成では、設計者側にとっても運転者側にとっても、最適化計算の計算内容を直感的に理解しにくい。また、最適化問題を解くアルゴリズムによっては、必ずしも大域的に最適な解が得られるわけではなく、局所的な最適解が解として得られてしまうことも多い。その場合、過度に保守的な解や、逆に設計者が意図したよりもリスクの高い解が得られる可能性があり、そうした場合には運転者に大きな違和感を与えてしまうことになる。
【００２４】
そのような問題を解決するために導入されたのが、運転方針決定手段３ｃである。合流車両１０が本線車両１１の前方に合流すべきか後方に合流すべきかの判定自体は、最適化計算のような複雑な計算手段に頼らなくても、もっと簡単な方法で計算することが可能であり、むしろ直感的には簡単な方法で計算した方がわかりやすい。合流挙動の個人差を考慮する場合も、直感的にわかりやすいロジックで構成した方が、チューニングが容易になる。
判定結果に沿った運転操作が算出されるように評価手段３ｂを構成する関数を修正すれば、最適化アルゴリズムが不適切な局所最適解を算出するリスクも減少することが期待できる。
ここでは、運転方針決定手段３ｃとして、図５に示すような構成の判定ロジックの例を説明する。
図５において、３ｃ−１は指標算出部、３ｃ−２は判断ロジックマップ、３ｃ−３は評価関数補正部である。３ｆは周囲環境情報、３ｇは補正内容である。
指標算出部３ｃ−１では、合流判断の基準となる指標を算出する。本実施の形態１においては、三つの指標に基づいて判断を行なう。
一つ目の指標は、合流車両１０が現在の車速を保った場合に、合流終端ｘ_ｅｎｄまで到達するまでの時間である終端到達時間ＴＴＥで、次式で計算される。
【００２５】
【数１２】

二つ目の指標は、合流車両１０と本線車両１１が共に現在の車速を保った場合に、本線車両１１が合流車両１０を追い抜くまでの時間である追抜き時間ＴＴＰで、次式で計算される。
【００２６】
【数１３】

追抜き時間ＴＴＰは、合流車両１０が本線車両１１の前方を走行し、なおかつ本線車両１１の速度が合流車両１０の速度よりも速い場合でないと意味をなさないが、意味をなさない場合にはそのことを示すフラグを立てることにより、識別するものとする。
三つ目の指標は、合流車両１０が本線車線１２に車線変更した場合に予想されるリスク（リスク関数ＲＰ）で、（７）、（８）式を流用する。
判断ロジックマップ３ｃ−２では、指標算出部３ｃ−１で算出した指標をもとに本線車両１１の前方に合流すべきか後方に合流すべきかを判定する。具体的なマップの例として、図６に示すようなマップを利用することができる。
【００２７】
図６のマップは次のような考え方に基づいて設計されている。
終端到達時間ＴＴＥと追抜き時間ＴＴＰの値が接近している場合、両車１０、１１が現在の車速を保つと、合流車両１０が合流終端ｘ_ｅｎｄに到達する頃に、ちょうど合流車両１０と本線車両１１が並走する状態となる。並走状態では合流が困難であることから、合流車両１０が減速するか、本線車両１１が加速するなどして、終端到達時間ＴＴＥと追抜き時間ＴＴＰの値が離れるようにしなければならない。そのような領域を領域２と名づけ、判定の閾値である定数ΔＴによって、次式を満たすような領域として定義する。
【００２８】
【数１４】

本実施の形態１では、周囲状況が領域２に属していると判定された場合には、合流車両１０の方が減速して、本線車両１１の後方へ合流するべき、と判断するロジックを構成する。
終端到達時間ＴＴＥの値が、追抜き時間ＴＴＰの値よりも十分に大きい場合には、両車１０、１１が現在の車速を保った場合に、合流車両１０が合流終端ｘ_ｅｎｄに到達する前に、本線車両１１が合流車両１０を追い抜くことが予想される。すなわち、合流車両１０は現在の車速を保っていれば、余裕をもって合流することが可能になると予想できるので、この場合も本線車両１１の後方へ合流するべき、と判断するロジックを構成する。この領域を領域１と名づけ、次式を満たすような領域として定義する。
【００２９】
【数１５】

終端到達時間ＴＴＥの値が、追抜き時間ＴＴＰの値よりも十分に小さい場合には、両車１０、１１が現在の車速を保った場合に、合流車両１０が合流終端ｘ_ｅｎｄに到達しても、まだ本線車両１１が合流車両１０の後方を走行している状態であることが予想される。これは、本線車両１１と合流車両１０との距離にかなり余裕がある状態と考えられる。従って、合流車両１０が加速すれば本線車両１１の前方に余裕をもって合流できると期待できる。そこで、この領域を領域３と名づけ、次式を満たす領域として定義する。
【００３０】
【数１６】

実際には、合流車両１０が合流終端ｘ_ｅｎｄに接近している場合には、本線車両１１との間に十分な余裕がなくても、領域３と判定される場合がある。そこで、本線車両１１との潜在リスク関数ＲＰを算出し、リスク関数ＲＰが所定の値ＲＰ_ｍｉｎよりも小さい場合にのみ、領域３に属すると判定し、本線車両１１の前方へ合流するべき、と判断するロジックを構成する。もし、リスク関数ＲＰが所定の値ＲＰ_ｍｉｎよりも大きい場合には、領域２に属するものと判定し、本線車両１１の後方へ合流するべき、と判断する。
なお、本線車両１１が合流車両１０を追い抜くまでの追抜き時間ＴＴＰが正常に算出されない場合は、本線車両１１がすでに合流車両１０を追い抜いているか、本線車両１１の速度が合流車両１０の速度よりも遅いかのどちらかである。前者の場合を領域４と名づけ、本線車両１１の後方へ合流するべき、と判断する。後者の場合を領域５と名づけ、本線車両１１の前方へ合流するべき、と判断する。
なお、合流車両１０が現在の車速を保った場合に合流終端ｘ_ｅｎｄまで到達するまでの終端到達時間ＴＴＥが負になるのは、既に合流を終えて合流終端ｘ_ｅｎｄを通過した場合になるので、判断を下す必要はない。
【００３１】
図５の評価関数補正部３ｃ−３では、判断ロジックマップ３ｃ−２の判断結果を受けて、評価手段３ｂ（図２）で定義される評価関数の補正内容を決定する。単純な方法としては、判断の結果に応じて、（３）式の関数ψを設定することが考えられる。関数ψは予測時刻終端における状態を評価する関数である。そこで、予測終端における合流車両１０と本線車両１１との縦方向の位置関係を評価し、もし本線車両１１の前方へ合流すべき、と判断されている場合には、ｘ_Ｔ（ｔ＋Ｔ）−ｘ_Ｍ（ｔ＋Ｔ）の値が小さければ小さいほどよい、という関数を設定し、逆に本線車両１１の後方へ合流すべき、と判断されている場合には、ｘ_Ｍ（ｔ＋Ｔ）−ｘ_Ｔ（ｔ＋Ｔ）の値が小さければ小さいほどよい、とする関数を設定する。具体的には、例えば
【００３２】
【数１７】

という関数が考えられる。ここで、ｗ_Ｐは重みパラメータである。
別の補正方法として、（６）式における希望車速のパラメータｖ_Ｍ ^＊を補正する方法が考えられる。判断ロジックマップ３ｃ−２によって、合流車両１０が取るべき操作が判断できたのであれば、そのような操作を実現するために合流車両１０が走行すべき走行車速を見積もることが可能である。そこで、見積もられた合流車両１０が走行すべき走行車速を（６）式における合流車両１０の希望車速のパラメータｖ_Ｍ ^＊に反映させれば、判断ロジックマップ３ｃ−２における判断内容に沿った推奨操作量を計算することができる。
例えば、領域１においては、合流車両１０が現在の車速を維持していれば、余裕を持って本線車両１１の後方に合流することができると予想されているので、目標車速を現在の車速と同じ値に設定すればよい。
一方、領域３においては、加速することによって本線車両１１の前方に余裕を持って合流が可能であると予想されている。合流車線１３における走行速度は、通常、本線車線１２における本来の走行車速（例えば、本線車線１２における制限最高速度）よりも低いので、本線車線１２における本来の走行車速を目標値に設定することが考えられる。あるいは、単純に本線車両１１の車速よりも所定の値だけ速い速度を設定する方法もある。
【００３３】
領域２は、このままの状態では余裕を持った合流が困難なことが予想される領域である。従って、領域１かあるいは領域３の状態に移行できるような操作を行なわなければならない。本線車両１１の後方に合流するという判断を下した場合には、まず現在の周囲環境を領域１へと移行させることが必要である。そこで、領域１へと移行するために必要な車速を計算することになる。領域１とは、（１５）式で定義される領域であるから、領域１へと移行するのに必要な車速は次式をｖ_Ｍについて解くことで計算することができる。
【００３４】
【数１８】

ただし、ｋは１以上の値を取る適当な定数である。（１８）式を解いて得られた解を、目標車速ｖ_Ｍ ^＊として設定する。
領域４は領域１に、領域５は領域３に準じて目標車速を設定すればよい。また、本線車線１２に合流した後は、本線車線１２における本来の走行車速が目標車速に設定される。
以上が、評価関数補正部３ｃ−３の処理の例である。なお、ここでは本線車両１１の目標車速は一定として、合流車両１０の目標車速だけを補正する例を説明したが、本線車両１１の目標車速も補正の対象とするロジックを構成することも可能である。
補正内容が図２の評価手段３ｂにおける評価関数に反映された上で、推奨操作量算出手段３ｄの処理が行なわれ、推奨操作量として、ｕ_ｘ ^Ｔ（τ）、ｕ_ｘ ^Ｍ（τ）、ｕ_ｙ ^Ｍ（τ）、ｔ≦τ≦ｔ＋Ｔが算出される。算出された解は、表示装置４に転送され、表示のための処理を施した上で、運転者に提示される。提示の方法としては、単純に自車に対する推奨操作量であるｕ_ｘ ^Ｍ（τ）とｕ_ｙ ^Ｍ（τ）を表示する方法や、あるいは得られた解の操作を実際に行なった場合に予想される結果を（１）、（２）式を用いて計算し、Ｔ秒後の周囲環境の予想図を表示する方法などが考えられる。さらに、運転方針決定手段３ｃにおいて計算された判断（本線車両１１の前方に合流すべきか、あるいは後方に合流すべきか）を併せて表示することで、よりわかりやすい情報提示とすることができる。
【００３５】
図７（ａ）に、図３の場面における推奨操作量算出手段３ｄによる推奨操作量の算出結果を示し、図７（ｂ）に表示装置４による運転者への表示方法の例を示す。図３の場面では、合流車両１０と本線車両１１の関係が、図２の運転方針決定手段３ｃによって、図６の領域２の状態であると判定される。従って、合流車両１０に対しては本線車両１１の後方へと合流するために減速した後で車線変更を行なう推奨操作量が算出される。一方、本線車両１１に関しては、一定速度を維持した後で、合流車両１０の車線変更に対応するためにわずかに加速を行なう推奨操作量が算出される。これらの操作量を取った場合に予想される各車１０、１１の挙動を算出し、表示装置４には現在（ここでは、ｔ＝０と仮定）および予測時間の終端であるτ＝Ｔにおける各車１０、１１の位置を模式的に表示する。また、運転方針決定手段３ｃにおいて後方に合流すべき、と判定されたことを、図７（ｂ）のごとく下向きの矢印と文字メッセージで併せて表示する。
【００３６】
以上の本実施の形態１における演算部３による処理の内容を図８のフローチャートにまとめる。
ステップ１では、路車間通信ユニット５ａ（図１、図２）の通信を通して、合流路に関する情報を取得する。具体的には、図３の合流可能区間１５の始端ｘ_{ｂｅｇｉｎ}と終端ｘ_ｅｎｄの情報を得る。
ステップ２では、周囲車両検出手段１を構成する各センサ１ａ〜１ｄからの情報を読み込む。
ステップ３では、自車状態検出手段２を構成する車速センサ２ａからの情報を読み込む。ステップ２とステップ３の処理によって、自車１０および周囲車両情報であるｘの値が確定する。
ステップ４では、デフォルトの評価関数を読み込む。
ステップ５では、運転方針決定手段３ｃにおいて用いられる合流判断の基準となる指標を計算する。本実施の形態１の場合、合流車両１０が現在の車速を保った場合に合流終端ｘ_ｅｎｄまで到達するまでの終端到達時間ＴＴＥ、本線車両１１が合流車両１０を追い抜くまでの追抜き時間ＴＴＰ、本線車線１２に車線変更することに対するリスク関数ＲＰの三つの指標が、指標算出部３ｃ−１によって算出される。
ステップ６では、ステップ５で指標算出部３ｃ−１により算出された指標と、判断ロジックマップ３ｃ−２とが照合され、現在の周囲環境において本線車両１１の前方へ合流すべきか、後方に合流すべきか、に関する判定が行なわれる。
ステップ７では、ステップ６における判定結果を参照して、評価関数補正部３ｃ−３により評価関数の補正内容を決定する。具体的には、終端評価項（予測の終端時刻における車群の状態ｘの望ましさを測る関数ψ）を設定する方法と、合流車両１０の目標車速ｖ_Ｍ ^＊を設定する方法を上記で説明した。
ステップ８では、運転方針決定手段３ｃの評価関数補正部３ｃ−３により補正された評価関数と、評価手段３ｂと、あらかじめ設定されている予測手段３ａから、推奨操作量算出手段３ｄを用いて、推奨操作量を算出する。
ステップ９では、推奨操作量算出手段３ｄにより算出された推奨操作量を受けて、運転者に対する運転支援情報が表示装置４に提示される。
以上説明したように本実施の形態１の車両用推奨操作量生成装置では、自車１０の走行状態を検出する自車状態検出手段２と、自車１０の周囲を走行する周囲車両１１を検出する周囲車両検出手段１と、自車１０の周囲の車線を検出する車線検出手段６と、自車１０の周囲で走行可能な車線が消滅している合流終端ｘ_ｅｎｄを検出する合流検出手段５と、自車１０および周囲車両１１が取り得る操作量から各車両１０、１１の未来の位置と速度を予測する予測手段３ａと、自車１０および周囲車両１１の位置、速度、および操作量から、車群全体としての状態の望ましさを数値的に評価する評価手段３ｂと、評価手段３ｂで算出される評価値の将来的な予測に基づいて、自車１０および周囲車両１１が取るべき加減速操作および車線変更操作のパターンを算出する推奨操作量算出手段３ｄと、車線の消滅が検出されている合流車線１３上を走行する合流車両１０と、合流車線１３に隣接する本線車線１２上を走行する本線車両１１との位置および速度関係から、合流車両１０が本線車両１１の前方に合流すべきか後方に合流すべきかを決定する運転方針決定手段３ｃとを備え、運転方針決定手段３ｃの計算結果に応じて評価手段３ｂに補正を加えるという構成になっている。
このように本実施の形態１では、運転方針決定手段３ｃによって本線車線１２を走行する本線車両１１の前方に合流すべきか後方に合流すべきかを判定し、判定した結果を評価手段３ｂの補正を通して反映させる構成となっている。運転方針決定手段３ｃを導入することによって、どのように合流すべきかに関するシステム側の判断を明確にすることができる他、運転方針決定手段３ｃの処理内容を変更することで、さまざまな運転者の合流特性に合わせた判断を再現することができる。また、評価手段３ｂの評価項の中に運転者にとっての違和感を抑制する項を含ませることで、算出される合流のための制御指令を、運転方針決定手段３ｃの判定結果に沿いつつ、運転者にとって違和感の小さいものにすることができる。すなわち、挙動の明確さと違和感の小ささを両立した制御指令を算出することができる。
【００３７】
また、合流検出手段５が、道路上に固定された通信装置と自車１０に搭載された通信装置との路車間通信（路車間通信ユニット５ａ）を通して得られる情報に基づいて合流終端ｘ_ｅｎｄを検出するという構成になっている。このように、路車間通信を利用することで、合流区間における道路構造に関する情報を高精度で得ることができるので、より精度、信頼性の高い制御指令を計算することができる。
また、運転方針決定手段３ｃが、合流車両１０が合流終端ｘ_ｅｎｄに到達するまでの時間の予測値である終端到達時間ＴＴＥと、合流車両１０が本線車両１１に追抜かれるまでの時間の予測値である追抜き時間ＴＴＰと、合流車両１０と本線車両１１との相対的な位置および速度の関係から算出される合流車両１０が本線車線１２に車線変更した場合に予想されるリスクの評価値（リスク関数ＲＰ）とに基づいて本線車両の前方に合流すべきか後方に合流すべきかを決定するという構成になっている。このように、合流可能な道路の区間が点ではなく長さをもった区間であるとみなせる合流車線１３において、終端到達時間ＴＴＥと追抜き時間ＴＴＰとを比較することで、現在の車速水準を保った場合に、合流終端ｘ_ｅｎｄ付近に到達するまでに余裕をもって合流するチャンスがあるかどうかを判定することができる。すなわち、前記特許文献に記載された従来技術では、合流地点を点で表現する構成となっているため、所定の広がりを持った区間内のどこでも合流可能であるような道路においては合流地点をあらかじめ決めなければいけないという問題があったが、本実施の形態１ではこの問題を解決できる。本線車線１２に車線変更した場合のリスクＲＰを併せて考慮することで、余裕のある合流を実現するために加速すべきなのか減速すべきなのかについての適切な判断を下すことができる。
【００３８】
また、運転方針決定手段３ｃが、リスクの評価値が所定の水準よりも低く、なおかつ終端到達時間ＴＴＥが追抜き時間ＴＴＰよりも所定の値以上に短い場合に本線車両１１の前方に合流すべきと判断し、それ以外の場合には後方に合流すべきと判断するという構成になっている。このように、現在の車速水準を保っていては本線車両１１に追い抜かれる前に合流終端ｘ_ｅｎｄに到達してしまうことが予想され、なおかつ本線車両１１と十分な余裕がある場合にのみ、本線車両１１の前方へ合流すべきであると判断するロジックを構成しているので、慎重な合流判断に基づいて制御指令を計算することができる。
また、評価手段３ｂが、合流車両１０が本線車線１２に車線変更した場合に予想されるリスクの評価値ＲＰと、合流車両１０が合流車線１３に留まることで予想されるリスクの評価値ＲＰとの比較を評価に含み、合流車線１３に留まるリスクＭＰが車線変更した場合に予想されるリスクＲＰを上回る場合に車線変更が指示されるという構成になっている。このように、合流車線１３に留まることに対するリスクＭＰを導入し、本線車線１２に合流することで予想されるリスクＲＰと比較することで合流の可否を判断しているので、合流可能な区間が点ではなく長さをもった区間であるとみなせる道路においても、合流すべき位置とタイミングを具体的に計算することができる。
【００３９】
また、評価手段３ｂが、合流車両１０が合流終端ｘ_ｅｎｄに近づくにつれてリスクの評価値ＲＰが大きく設定されるという構成になっている。このように、合流終端ｘ_ｅｎｄに近づくほど合流車線１３に留まることに対するリスクＭＰを大きく見積もっているので、合流終端ｘ_ｅｎｄに近づくにつれて合流を指示するような制御指令が得られやすくなり、合流できないまま合流終端ｘ_ｅｎｄまで到達してしまう制御指令が生成されることを抑制することができる。
【００４０】
また、評価手段３ｂが、各車両１０、１１の希望走行車速の想定値ｖ_Ｔ ^＊、ｖ_Ｍ ^＊と実際の走行車速との偏差を評価に含み、各車両１０、１１の希望走行車速の想定値ｖ_Ｔ ^＊、ｖ_Ｍ ^＊を運転方針決定手段３ｃで決定された運転方針に基づいて補正するという構成になっている。このように、希望走行車速というパラメータを通して運転方針に関する判断を制御指令の計算に反映させるという構成になっているので、パラメータの変更という簡単な数学的操作だけで運転方針決定手段の判断結果を制御指令の計算結果に反映させることができる。
【００４１】
以上が本発明の実施の形態１である。
【００４２】
実施の形態２
本発明の実施の形態２を、図９から図１１までの図面に基づいて説明する。
図９は本実施の形態２の車両用推奨操作量生成装置を構成するのに必要な配置図である。基本的な構成は実施の形態１と同じであり、唯一異なるのは、合流検出手段５（図２参照）として、路車間通信ユニット（図１の５ａ）ではなく、ナビゲーションシステム５ｂが搭載されていることである。すなわち、本実施の形態２においては、合流車線に関する情報を路車間通信ではなく、ナビゲーションシステム５ｂから得る構成となっている。図２に示した実施の形態１における演算部３の構成と各ブロックの処理の内容は、実施の形態２においてもまったく同一である。
【００４３】
図１０の場面における装置の動作について説明する。図１０は実施の形態１の適用場面の例である図３の場面と、自車と他車とが入れ替わっただけで、あとはまったく同一の場面である。図１０において、１０ａは本線車両（自車）、１１ａは合流車両（他車）である。
図１０において、自車１０ａはナビゲーションシステム５ｂから現在値情報と地図情報データベースの情報を得て、自車１０ａの走行車線である本線車線１２の右側の車線が合流車線１３であり、前方で自車１０ａの本線車線１２に合流してくることを検出する。すなわち、自車１０ａの右側の合流車線１３を走行する車両が合流車両１１ａであると判別する。
以後の処理は、実施の形態１とまったく同じように進み、推奨操作量としてｕ_ｘ ^Ｔ（τ）、ｕ_ｘ ^Ｍ（τ）、ｕ_ｙ ^Ｍ（τ）、ｔ≦τ≦ｔ＋Ｔが算出される。
運転者に提示する情報についても、実施の形態１と同種のものを用いることができる。例えば、図１０の場面における表示装置４の表示内容は、図１１（ｂ）のようなものになる。
このように本実施の形態２では、合流検出手段（図２の５参照）が、ナビゲーションシステム５ｂ（図９）から得られる道路構造に関する情報に基づいて合流終端ｘ_ｅｎｄを検出するという構成になっている。従って、ナビゲーションシステム５ｂから得られる現在位置に関する情報と地図情報データベースに記録されている道路の構造に関する情報を照合することで、どの車線が前方において消滅する合流車線に該当しているのかを判別することができる。
【００４４】
以上が本発明の実施の形態２である。
【００４５】
実施の形態３
本発明の実施の形態３を、図１２および図１３の図面に基づいて説明する。
本実施の形態３の配置図は、図９に示した実施の形態２と同一である。ただし、本実施の形態３のナビゲーションシステム５ｂにおいては、ＧＰＳ信号だけでなく、ＦＭ多重放送等の道路情報に関する信号を受信する機能も備えているものとする。
図１２に本実施の形態３の適用場面の一例を示す。図１２は自車１０が右車線を走行し、左車線後方に他車１１が走行している場面である。本実施の形態３においては、道路工事や事故等に伴う規制された車線（規制車線１７）の情報を受信して、自車１０が該当地点に近づいた場合に、規制車線１７を合流車線とみなして運転者に推奨操作量を提示する構成としている。自車１０の前方の右車線（規制車線１７）では事故による車線規制が行なわれていて、事実上、車線が消滅している。本実施の形態３では、そのような車線規制の情報を道路情報信号を受信することで検出する。規制されている車線は、実施の形態１、２における合流車線と同種の車線であるとみなし、車線規制が行なわれている手前の適当な地点に仮想的な合流終端ｘ_ｅｎｄを設定する。そのようにして、合流終端ｘ_ｅｎｄを設定すると、推奨操作量生成の問題は、数学的には実施の形態１、２とまったく同じ問題となり、実施の形態１、２の演算部３と同じアルゴリズムによって、推奨操作量を生成することができる。
運転者に提示する情報についても、実施の形態１、２と同種のものを用いることができる。例えば、図１２の場面における表示装置４の表示内容は、図１３（ｂ）のようなものになる。
【００４６】
このように本実施の形態３では、合流検出手段（図２の５参照）が、ＦＭ多重放送等の無線放送を受信することによって得られる事故および道路工事に関する情報に基づいて合流終端ｘ_ｅｎｄを検出するという構成になっている。従って、無線放送で提供される事故、工事等による車線規制の情報を取り込むことで、地図情報データベースだけでは把握しきれない車線の消滅地点に関する情報が得られ、より多様な場面に対応できる。
【００４７】
以上が本発明の実施の形態３である。
【００４８】
以上本発明を実施の形態に基づいて具体的に説明したが、本発明は上記実施の形態に限定されるものではなく、その要旨を逸脱しない範囲において種々変更可能であることは勿論である。
【図面の簡単な説明】
【図１】本発明の実施の形態１の車両用推奨操作量生成装置の配置図である。
【図２】本発明の実施の形態１における装置の機能別ブロックの構成を示す図である。
【図３】本発明の実施の形態１の適用場面の一例を示す図である。
【図４】本発明の実施の形態１における合流車線に留まることに対するリスク関数の一例を示す図である。
【図５】本発明の実施の形態１における運転方針決定手段のブロック線図である。
【図６】本発明の実施の形態１の運転方針決定手段における判断ロジックマップの一例を示す図である。
【図７】本発明の実施の形態１における推奨操作量の算出結果とその表示方法の一例を示す図である。
【図８】本発明の実施の形態１における処理のフローチャートを示す図である。
【図９】本発明の実施の形態２の車両用推奨操作量生成装置の一配置図である。
【図１０】本発明の実施の形態２の適用場面の一例を示す図である。
【図１１】本発明の実施の形態２における推奨操作量の算出結果とその表示方法の一例を示す図である。
【図１２】本発明の実施の形態３の適用場面の一例を示す図である。
【図１３】本発明の実施の形態３における推奨操作量の算出結果とその表示方法の一例を示す図である。
【符号の説明】
１…周囲車両検出手段
１ａ…前方レーダー
１ｂ…画像センサ
１ｃ…後方レーダー
１ｄ…側方センサ
２…自車状態検出手段
２ａ…車速センサ
３…演算部
３ａ…予測手段
３ｂ…評価手段
３ｃ…運転方針決定手段
３ｃ−１…指標算出部
３ｃ−２…判断ロジックマップ
３ｃ−３…評価関数補正部
３ｄ…推奨操作量算出手段
３ｆ…周囲環境情報
３ｇ…補正内容
４…表示装置
５…合流検出手段
５ａ…路車間通信ユニット
５ｂ…ナビゲーションシステム
６…車線検出手段
６ａ…
１０…合流車両（自車）
１０ａ…本線車両（自車）
１１…本線車両（他車）
１１ｂ…合流車両（他車）
１２…本線車線
１３…合流車線
１４…合流禁止区間
１５…合流可能区間
１６…合流完了区間
１７…規制車線[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a recommended operation amount generating device for a vehicle.
[0002]
[Prior art]
[Patent Document] JP-A-10-105895.
[0003]
Hereinafter, the lane where the lane disappears is referred to as "merging lane", the lane adjacent to the merging lane is "main lane", vehicles traveling on the merging lane are "merging vehicles", and vehicles traveling on the main lane are "main lanes". This will be described.
In the above patent document, the time until the merging vehicle reaches the merging point and the time until the main line vehicle reaches the merging point are calculated, and when the time to reach the merging point of the two vehicles is approaching, Discloses an invention relating to a device for transmitting control information (acceleration / deceleration control command) or warning information to one or both vehicles.
[0004]
[Problems to be solved by the invention]
In the invention disclosed in the above-mentioned patent documents, when the time when both the merging vehicle and the main line vehicle arrive at the merging point is approaching, the time to reach the merging point of either vehicle or both vehicles is simply determined. , The acceleration / deceleration control command is transmitted so as to shift, and there is a problem that the commanded acceleration / deceleration command does not sufficiently consider the possibility of causing the driver to feel uncomfortable.
An object of the present invention is to provide a recommended operation amount generation device for a vehicle, which can make a control command for merging of vehicles less uncomfortable for a driver.
[0005]
[Means for Solving the Problems]
In order to solve the above problems, the present invention provides a vehicle state detecting means for detecting a running state of the vehicle, a surrounding vehicle detecting means for detecting a surrounding vehicle of the own vehicle, and a lane detecting means for detecting a surrounding lane. Merging detection means for detecting a merging end around the own vehicle, prediction means for predicting the future position and speed of each vehicle from the amount of operation that can be taken by the own vehicle and the surrounding vehicles, the position of the own vehicle and the surrounding vehicles, Evaluating means for evaluating the desirability of the state of the entire vehicle group from the speed and the operation amount, and acceleration / deceleration to be taken by the own vehicle and surrounding vehicles based on future prediction of the evaluation value calculated by the evaluating means. From the position and speed relationship between the recommended operation amount calculating means for calculating the operation and lane change operation patterns, the merging vehicle traveling on the merging lane, and the main vehicle traveling on the main lane, the merging vehicle is located ahead of the main lane vehicle. Should we join And a driving policy determining means for determining whether to merge towards has a structure of adding a correction to the evaluation unit in accordance with the calculation result of operation policy determining means.
[0006]
【The invention's effect】
ADVANTAGE OF THE INVENTION According to this invention, the control command for the merging of vehicles can be made less uncomfortable for the driver.
[0007]
BEST MODE FOR CARRYING OUT THE INVENTION
Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. In the drawings described below, those having the same functions are denoted by the same reference numerals, and repeated description thereof will be omitted.
Embodiment 1
First Embodiment A first embodiment of the present invention will be described with reference to FIGS.
FIG. 1 is an arrangement diagram necessary for configuring the vehicle recommended operation amount generation device according to the first embodiment.
In FIG. 1, a front radar 1a is attached to the front of a host vehicle (hereinafter, referred to as host vehicle 10) and measures the positions of a plurality of vehicles located in front of the host vehicle 10. The image sensor 1b is also mounted at an appropriate position on the front of the vehicle 10, complements the measurement information of the forward radar 1a, and detects a lane drawn on the road. The rear radar 1c is attached to the back of the vehicle 10 and measures the positions of a plurality of vehicles located behind. The side sensors 1d are attached one by one to the left and right side surfaces of the own vehicle 10, and detect the position of the vehicle located on the side of the own vehicle 10 as a blind spot of the forward radar 1a and the backward radar 1c. Note that a radar can be used as the side sensor 1d, but an ultrasonic sensor or an image sensor can be used.
The vehicle speed sensor 2a can be realized by attaching a rotary encoder to a wheel. A pulse train having a cycle corresponding to the rotation speed of the wheel is output, and a measured value of the vehicle speed of the vehicle 10 is obtained.
The arithmetic unit 3 is composed of a microcomputer and its peripheral parts, processes signals from the forward radar 1a, the image sensor 1b, the backward radar 1c, the side sensor 1d, and the vehicle speed sensor 2a in accordance with a program recorded in a built-in memory, and performs calculations. The result is sent to the display device 4.
The display device 4 is composed of a display for display such as a liquid crystal screen, a microcomputer for drawing an image to be displayed on the display, and its peripheral parts. The signal sent from the arithmetic unit 3 is stored in a built-in memory. The information is presented to the driver by processing according to the program and drawing the image on the display.
The road-to-vehicle communication unit 5a receives a signal transmitted from a communication device installed on the road side, and transfers information on a road structure near the junction to the calculation unit 3.
[0008]
The computing unit 3 constitutes each block shown in FIG. 2, that is, a prediction unit 3a, an evaluation unit 3b, an operation policy determination unit 3c, and a recommended operation amount calculation unit 3d by a software form of a microcomputer. As shown in FIG. 2, the own vehicle state detecting means 2 is detected by the vehicle speed sensor 2a, and the surrounding vehicle detecting means 1 is detected by the surrounding sensors of the front radar 1a, the image sensor 1b, the rear radar 1c, and the side sensor 1d. The lane detecting means 6 is constituted by the image sensor 1b as a container, and the merging detecting means 5 is constituted by the road-vehicle communication unit 5a. In the calculation unit 3 of FIG. 2, 3f indicates ambient environment information, and 3g indicates correction contents.
[0009]
Hereinafter, a specific configuration method of each block will be described based on an example of an operation in a road situation as shown in FIG.
FIG. 3 shows a situation in which a merging lane 13 is connected to a main lane 12 of one lane. In FIG. 3, a scene in which the road near the junction is divided into three sections and handled can be considered. That is, in the merging prohibited section 14 on the front side, the two lanes 12 and 13 are physically separated from each other, or there is a section where entry is prohibited according to the road traffic rules. It is treated as a section that cannot be moved. The merging possible section 15 following the merging prohibited section 14 is treated as a section that can freely move between the two lanes 12 and 13. At the end of the merging, the merging lane 13 is interrupted, and only the main lane 12 becomes a lane in which the vehicle can travel. Here, the x-axis is taken in the traveling direction of the lane, and the starting point of merging of the merging section 15 is x_begin, X_endNotation.
In such a road condition, consider a case where the own vehicle (merging vehicle) 10 is traveling on the merging lane 13 and another vehicle (main vehicle) 11 is traveling behind the own vehicle 10 on the main lane 12. . Variables representing the position and speed of the vehicle 10 are represented by x_M, V_MAnd the variables representing the position and speed of the other vehicle 11 are x_T, V_TNotation. Also, y is a variable representing the lane position of the vehicle 10 traveling on the merging lane 13._MIs defined as -1 when traveling on the merging lane 13 and as 1 when traveling on the main lane 12. In addition, since it is normally not considered that another vehicle 11 traveling on the main lane 12 changes lanes to the merging lane 13, the lane position is represented as that the other vehicle 11 keeps traveling on the main lane 12. No variables are defined.
The relative position and speed between the own vehicle 10 and the other vehicle 11 can be obtained from the information from the surrounding sensors 1a to 1d constituting the surrounding vehicle detecting means 1. By appropriately setting the origin of the coordinate system, x_MAnd x_TCan be obtained. Further, based on information from a vehicle speed sensor 2a constituting the own vehicle state detecting means 2, the speed v of the own vehicle 10 is obtained._MIs obtained, the speed v of the other vehicle 11 is obtained by adding the speed of the own vehicle 10 to the relative speed._TCan also be obtained. From the information obtained from the lane detecting means 6, y_MCan also be obtained. Further, the communication between the road-to-vehicle communication unit (not shown) fixed at an appropriate position on the road and the vehicle-to-vehicle road-to-vehicle communication unit 5a allows the merging start point x to be established._beginAnd end point x_endInformation can be obtained. As described above, all the measurement signals of the sensors 1a to 1d, 2a, and 5a are transmitted to the arithmetic unit 3, and by performing the processing described above, the position x of the own vehicle 10 is obtained._M, The speed v of the vehicle 10_M, A variable y representing the lane position of the vehicle 10_M, The position x of the other vehicle 11_T, The speed v of the other vehicle 11_T, Start point x_begin, Junction end x_endIs determined, and these pieces of information are collectively held as the surrounding environment information 3f.
[0010]
The prediction means 3a in the arithmetic unit 3 is a block for predicting and calculating how each of the vehicles 10, 11 moves with respect to an operation that the own vehicle 10 and another vehicle 11 can take. Specifically, for example, it can be constituted by the following differential equation.
[0011]
(Equation 1)

[0012]
(Equation 2)

Where u_x ^T, U_x ^MAre the acceleration / deceleration command values of the main line vehicle 11 and the merging vehicle 10, respectively, and u_y ^MIs a command value relating to a lane change of the merging vehicle 10, and here, a variable y_MIs defined as a command value for. That is, it takes a value of -1 when staying in the merging lane 13 and a value of 1 when merging in the main lane 12. ω is an appropriate positive constant, and the command value u_y ^MIs changed stepwise from -1 to 1, the variable y_MIs set to a value such that the time required for the transition from -1 to 1 to be approximately equal to the time required from the start to the completion of the lane change in the actual lane change operation. From the above differential equation, u representing the operation of the main line vehicle 11 and the merging vehicle 10_x ^T, U_x ^M, U_y ^MGiven the time series pattern and the initial value of each variable, it is possible to calculate how the main line vehicle 11 and the merging vehicle 10 move in response to such an operation. The initial value of each variable is given by the measured surrounding environment information 3f. The above is the processing content of the prediction means 3a.
Note that “•” represents time differentiation, and in formulas with parentheses (), “•” is assumed to be above a variable, and superscript “•” and “•” above a variable are consent. I do.
[0013]
The evaluation means 3b numerically evaluates the operations performed by the main line vehicle 11 and the merged vehicle 10 and the desirability of the future surrounding environment expected when such operations are performed by introducing appropriate standards. The block to be evaluated. Specifically, for example, the evaluation can be performed by defining the following evaluation function.
[0014]
(Equation 3)

Where x (τ) = (x_T(Τ) v_T(Τ) x_M(Τ) v_M(Τ) y_M(Τ))^T, U (τ) = (u_x ^T(Τ) u_x ^M(Τ) u_y ^M(Τ))^TWhere t is a variable that represents the time that has actually elapsed, τ is a variable that represents the time when performing the prediction calculation, and T is a constant that represents the length of the prediction time. The evaluation function L is a function for numerically measuring the desirability of the state x and the operation amount u of the vehicle group at the time τ based on an appropriate standard. Here, the evaluation function L is defined as a function in which a smaller value indicates a more desirable state. . Similarly, the evaluation function ψ is a function for measuring the desirability of the state x of the vehicle group at the end time of the prediction.
Equation (3) represents an expected evaluation when input u (τ) and t ≦ τ ≦ t + T are added at time t. By introducing such an evaluation, it becomes possible to evaluate what operation the main line vehicle 11 and the merging vehicle 10 perform to achieve an appropriate merging behavior. Then, if an operation that makes the evaluation of the expression (3) as good as possible is presented to the driver as a control command, it is possible to support the driving in the merging scene.
The evaluation function L is composed of several functions expressing the demands for desired driving, and is put together as one function by taking a linear weighted sum of the functions. An example of a specific function configuration method will be described below.
As the first request, a request that the operation of acceleration / deceleration is as small as possible can be considered. This is a request in consideration of the fact that large acceleration / deceleration may cause discomfort or discomfort to a driver or an occupant. The following function is introduced as a function expressing such a request.
[0015]
(Equation 4)

As the second request, a request not to change lanes frequently can be considered. This is for the purpose of preventing calculation of a command to return to the merging lane 13 after commanding to merge into the main lane 12. In particular,
[0016]
(Equation 5)

It is expressed by the function
As a third request, a request to continue traveling at a speed as close as possible to the desired traveling vehicle speed of each of the vehicles 10 and 11 can be considered. This request also corresponds to the fact that being forced to travel at a speed that is significantly different from the desired traveling vehicle speed may cause the driver to feel uncomfortable or uncomfortable. In particular,
[0017]
(Equation 6)

It is expressed by the function Where v_T ^*, V_M ^*Are parameters representing desired traveling vehicle speeds (target vehicle speeds) of the main line vehicle 11 and the merging vehicle 10, respectively.
As a fourth request, when the merging vehicle 10 is in the merging lane 13, the merging end x_endIt can be considered that the vehicle is not too close to the main line lane 12 and not too close to the main line vehicle 11. This is a basic requirement for achieving a marginal merge. Here, the merging end x_endIs expressed as a risk that the merging vehicle 10 stays in the merging lane 13, and the request that the merging vehicle 10 does not move too close to the main vehicle 11 is determined by the vertical position of the two vehicles 10 and 11. Expressed by the risk defined from the speed relationship. As a function expressing the risk associated with staying in the merging lane 13, MP (x_M). As a specific function form, for example, a function as shown in FIG. 4 can be considered. In FIG. 4, MP_min, MP_maxIs a minimum value and a maximum value of the risk function, and α is a constant taking a value from 0 to 1. As shown in FIG._endBy increasing the value of the risk towards_endIn the vicinity of, it can be expected that a control command that places more importance on the lane change to the main lane 12 is calculated.
The risk between the main line vehicle 11 and the merging vehicle 10 is evaluated here by the reciprocal of the inter-vehicle time (inter-vehicle distance / following vehicle speed) and the collision time (inter-vehicle distance / relative speed). As a specific risk function,
[0018]
(Equation 7)

[0019]
(Equation 8)

Is introduced. Here, β is a constant taking a value from 0 to 1. The risk function MP (x for staying in the merging lane 13 introduced above_M) And a risk function RP (x (x) for changing lanes to the main lane 12)_T, V_T, X_M, V_M) Is switched according to the position of the traveling lane of the merging vehicle 10, which is the expression function of the fourth request. That is,
[0020]
(Equation 9)

An expression function such as Here, the function c is a continuous function that satisfies c (−1) = 0 and c (1) = 1.
[0021]
(Equation 10)

Can be used.
By the linear weighted sum of the above evaluation terms, an evaluation function L representing the overall evaluation is configured as in the following equation.
[0022]
(Equation 11)

On the other hand, the function ψ need not always be defined. Since the calculation result of the driving policy determining means 3c, which will be described later, can be used as one of means for reflecting the result in the evaluation, an example will be described again in the description of the driving policy determining means 3c.
The above is the configuration example of the evaluation unit 3b.
[0023]
When the equations (1) and (2) relating to the predicting means 3a and the equations (3) and (11) relating to the estimating means 3b are defined, an optimal method of obtaining u which minimizes the evaluation function of the equation (3) Control problems can be defined. The solution obtained by solving the optimal control problem can be expected to be an operation amount that reproduces an appropriate merging behavior if the evaluation function is appropriately designed. Therefore, the assist of the merging behavior can be realized by presenting the calculated operation amount to the driver. For a vehicle other than the own vehicle 10, the same operation as the operation obtained as a solution to the optimal control problem is not always performed. However, if the evaluation function is appropriately designed, the obtained operation is a standard operation. It can be expected that the driving operation that is expected to be taken by the person is good. Even if the prediction is incorrect, if the optimal solution is updated as needed, a solution based on the new prediction is calculated at the time when the prediction is incorrect, so that the amount of operation corresponding to the new situation Can be presented.
The systematic solution of the optimal control problem is well studied (for example, Reference 1: An approach to engineering optimal control nonlinearity by Kanichiro Kato, Reference 2: T. Ohtsuka, "Continuation / GMRES method for fast algorithm of nonlinear receiving) Horizon control ”Proc. 39th IEEE Conference on Decision and Control, pp. 766-771, 2000), and many methods for efficiently calculating solutions have been proposed. The recommended operation amount calculating means 3d is a block for performing processing for actually calculating the recommended operation amount by performing such calculation.
The amount of operation that can be obtained as a solution to the optimal control problem depends on the design of the evaluation terms incorporated in the evaluation means 3b, and effectively suppresses the driver's discomfort and discomfort that were not sufficiently considered in the prior art. Can be expected. However, the more important information for the driver in the merging scene seems to be information directly instructing whether to merge ahead of the main line vehicle 11 or to merge backward. There is no element that directly expresses such a judgment in each function that constitutes the evaluation means 3b, and it is configured such that it is only after performing the optimization calculation whether it is possible to know whether to merge forward or backward. However, with such a configuration, it is difficult for the designer and the driver to intuitively understand the contents of the optimization calculation. Further, depending on the algorithm for solving the optimization problem, a globally optimum solution is not always obtained, and a local optimum solution is often obtained as a solution. In that case, there is a possibility that an overly conservative solution or a solution with a higher risk than intended by the designer may be obtained, and in such a case, the driver will be greatly discomforted.
[0024]
The operation policy determining means 3c has been introduced to solve such a problem. The determination itself as to whether the merging vehicle 10 should merge before or behind the main line vehicle 11 can be calculated by a simpler method without resorting to complicated calculation means such as optimization calculation. Yes, rather intuitively, it is easier to understand when calculating with a simple method. Even when individual differences in merging behavior are considered, tuning is easier if configured with intuitive logic.
If the function constituting the evaluation means 3b is corrected so that the driving operation according to the determination result is calculated, it is expected that the risk of the optimization algorithm calculating an inappropriate local optimum solution is reduced.
Here, an example of a determination logic having a configuration as shown in FIG. 5 will be described as the driving policy determining means 3c.
In FIG. 5, 3c-1 is an index calculation unit, 3c-2 is a judgment logic map, and 3c-3 is an evaluation function correction unit. 3f is surrounding environment information, and 3g is correction content.
The index calculation unit 3c-1 calculates an index serving as a criterion for determining merging. In the first embodiment, the determination is made based on three indices.
The first index is that when the merging vehicle 10 keeps the current vehicle speed, the merging end x_endThe terminal arrival time TTE, which is the time required to reach, is calculated by the following equation.
[0025]
(Equation 12)

The second index is an overtaking time TTP, which is the time until the main line vehicle 11 overtakes the merged vehicle 10 when both the merging vehicle 10 and the main line vehicle 11 maintain the current vehicle speed, and is calculated by the following equation. .
[0026]
(Equation 13)

The overtaking time TTP is meaningless unless the merging vehicle 10 is traveling ahead of the main line vehicle 11 and the speed of the main line vehicle 11 is faster than the speed of the merging vehicle 10. It is identified by setting a flag indicating the fact.
The third index is a risk (risk function RP) expected when the merging vehicle 10 changes lanes to the main lane 12, and the equations (7) and (8) are diverted.
In the determination logic map 3c-2, it is determined whether to merge ahead or behind the main line vehicle 11 based on the index calculated by the index calculation unit 3c-1. As a specific example of the map, a map as shown in FIG. 6 can be used.
[0027]
The map of FIG. 6 is designed based on the following concept.
When the value of the end time TTE and the value of the overtaking time TTP are close to each other, if the two vehicles 10 and 11 maintain the current vehicle speed, the merging vehicle 10 moves to the merging end x_end, The merging vehicle 10 and the main line vehicle 11 are running in parallel. Since it is difficult to join in the parallel running state, the value of the end arrival time TTE and the value of the overtaking time TTP must be separated by, for example, decelerating the merging vehicle 10 or accelerating the main line vehicle 11. Such an area is referred to as an area 2 and is defined as an area that satisfies the following equation by a constant ΔT that is a threshold for determination.
[0028]
[Equation 14]

In the first embodiment, when it is determined that the surrounding situation belongs to the area 2, the logic that determines that the merging vehicle 10 should be decelerated and merged behind the main line vehicle 11 is configured. I do.
When the value of the terminal arrival time TTE is sufficiently larger than the value of the overtaking time TTP, when the two vehicles 10 and 11 maintain the current vehicle speed, the merging vehicle 10 becomes the merging terminal x_endIt is expected that the main line vehicle 11 will overtake the merging vehicle 10 before reaching. That is, if the merging vehicle 10 maintains the current vehicle speed, it can be expected that the merging vehicle 10 will be able to merge with a margin. Therefore, in this case, the logic for determining that the merging vehicle 10 should merge behind the main line vehicle 11 is configured. This area is named area 1 and is defined as an area that satisfies the following equation.
[0029]
[Equation 15]

When the value of the terminal arrival time TTE is sufficiently smaller than the value of the overtaking time TTP, when the two vehicles 10 and 11 maintain the current vehicle speed, the merging vehicle 10 becomes the merging terminal x_end, It is expected that the main line vehicle 11 is still traveling behind the merged vehicle 10. This is considered to be a state where the distance between the main line vehicle 11 and the merging vehicle 10 has a considerable margin. Therefore, if the merging vehicle 10 accelerates, it can be expected that the merging vehicle 10 can merge ahead of the main line vehicle 11 with a margin. Therefore, this region is named region 3 and is defined as a region satisfying the following expression.
[0030]
(Equation 16)

In actuality, the merging vehicle 10 has the merging end x_endWhen the vehicle is approaching, the vehicle may be determined to be in the area 3 even if there is not enough room between the vehicle and the main line vehicle 11. Therefore, a potential risk function RP with the main line vehicle 11 is calculated, and the risk function RP is set to a predetermined value RP_minOnly when it is smaller than this, the logic that determines that it belongs to the area 3 and determines that it should merge ahead of the main line vehicle 11 is configured. If the risk function RP is a predetermined value RP_minIf it is larger, it is determined that it belongs to the area 2 and it is determined that it should join behind the main line vehicle 11.
If the overtaking time TTP until the main line vehicle 11 overtakes the merged vehicle 10 is not calculated normally, the main line vehicle 11 has already passed the merged vehicle 10 or the speed of the main line vehicle 11 is lower than the speed of the merged vehicle 10. Either is slow. The former case is named area 4, and it is determined that it should join behind the main line vehicle 11. The latter case is named area 5, and it is determined that it should join ahead of the main line vehicle 11.
Note that when the merging vehicle 10 maintains the current vehicle speed, the merging end x_endThe terminal arrival time TTE until reaching the point Tg becomes negative because the merging has already ended and the merging end x_endYou don't need to make a decision.
[0031]
The evaluation function correction unit 3c-3 in FIG. 5 receives the determination result of the determination logic map 3c-2 and determines the correction content of the evaluation function defined by the evaluation unit 3b (FIG. 2). As a simple method, it is conceivable to set the function の of the equation (3) according to the result of the determination. The function ψ is a function for evaluating the state at the end of the predicted time. Therefore, the longitudinal positional relationship between the merging vehicle 10 and the main line vehicle 11 at the predicted end point is evaluated, and if it is determined that the merging vehicle 10 should merge ahead of the main line vehicle 11, x_T(T + T) -x_MA function is set such that the smaller the value of (t + T), the better, and if it is determined that the vehicle should merge behind the main line vehicle 11, x_M(T + T) -x_TA function is set, such that the smaller the value of (t + T), the better. Specifically, for example,
[0032]
[Equation 17]

Function is considered. Where w_PIs a weight parameter.
As another correction method, the parameter v of the desired vehicle speed in the equation (6) is used._M ^*Is conceivable. If the operation to be taken by the merged vehicle 10 can be determined from the determination logic map 3c-2, it is possible to estimate the traveling vehicle speed at which the merged vehicle 10 should travel to realize such an operation. Therefore, the estimated traveling speed at which the combined vehicle 10 should travel is determined by the parameter v of the desired vehicle speed of the combined vehicle 10 in equation (6)._M ^*, It is possible to calculate the recommended operation amount in accordance with the judgment contents in the judgment logic map 3c-2.
For example, in the area 1, if the merging vehicle 10 maintains the current vehicle speed, it is expected that the merging vehicle 10 can merge behind the main line vehicle 11 with a margin, so that the target vehicle speed is set to the current vehicle speed. It should be set to the same value.
On the other hand, in the area 3, it is expected that the vehicle can be joined with a margin ahead of the main line vehicle 11 by accelerating. Since the traveling speed in the merging lane 13 is usually lower than the original traveling speed in the main lane 12 (for example, the maximum speed limit in the main lane 12), it is possible to set the original traveling speed in the main lane 12 to the target value. Conceivable. Alternatively, there is a method of simply setting a speed higher by a predetermined value than the speed of the main line vehicle 11.
[0033]
Region 2 is a region where it is expected that it is difficult to join with a margin in this state. Therefore, an operation must be performed so that the state can be shifted to the area 1 or the area 3. If it is determined that the vehicle merges behind the main line vehicle 11, it is necessary to first shift the current surrounding environment to the area 1. Therefore, the vehicle speed required to shift to the area 1 is calculated. Since the area 1 is an area defined by the equation (15), the vehicle speed required for shifting to the area 1 is represented by the following equation._MCan be calculated by solving
[0034]
(Equation 18)

Here, k is an appropriate constant taking a value of 1 or more. The solution obtained by solving equation (18) is calculated as the target vehicle speed v_M ^*Set as
The target vehicle speed may be set in the area 4 in the area 1 and in the area 5 in the area 3. After merging with the main lane 12, the original traveling vehicle speed in the main lane 12 is set to the target vehicle speed.
The above is an example of the processing of the evaluation function correction unit 3c-3. Here, an example has been described in which the target vehicle speed of the main line vehicle 11 is fixed and only the target vehicle speed of the merged vehicle 10 is corrected. However, it is also possible to configure a logic that corrects the target vehicle speed of the main line vehicle 11 as well. is there.
After the correction contents are reflected on the evaluation function in the evaluation means 3b of FIG. 2, the processing of the recommended operation amount calculation means 3d is performed, and u is set as the recommended operation amount._x ^T(Τ), u_x ^M(Τ), u_y ^M(Τ), t ≦ τ ≦ t + T is calculated. The calculated solution is transferred to the display device 4, processed for display, and presented to the driver. As a method of presentation, u is simply a recommended operation amount for the vehicle._x ^M(Τ) and u_y ^MThe method of displaying (τ) or the result expected when the operation of the obtained solution is actually performed is calculated using equations (1) and (2), and the surrounding environment is predicted after T seconds. A method of displaying a diagram may be considered. Furthermore, by displaying together the judgment (whether to join ahead or behind the main line vehicle 11) calculated by the driving policy determination means 3c, it is possible to provide more easily understandable information presentation.
[0035]
FIG. 7A shows a calculation result of the recommended operation amount by the recommended operation amount calculation means 3d in the scene of FIG. 3, and FIG. 7B shows an example of a method of displaying to the driver by the display device 4. In the scene of FIG. 3, the relationship between the merging vehicle 10 and the main line vehicle 11 is determined by the driving policy determining means 3c in FIG. 2 to be in the state of the area 2 in FIG. Therefore, a recommended operation amount for changing lanes after deceleration for the merging vehicle 10 to merge behind the main line vehicle 11 is calculated. On the other hand, for the main line vehicle 11, after maintaining a constant speed, a recommended operation amount for slightly accelerating in order to cope with a lane change of the merged vehicle 10 is calculated. The behavior of each of the vehicles 10 and 11 expected when these manipulated variables are taken is calculated, and the display device 4 displays the current (here, t = 0) and the end of the prediction time at τ = T. The positions of the vehicles 10 and 11 are schematically displayed. In addition, the fact that the driving policy determination means 3c has determined that the vehicle should merge backward is displayed together with a downward arrow and a text message as shown in FIG. 7B.
[0036]
The content of the processing by the arithmetic unit 3 in the first embodiment described above is summarized in the flowchart of FIG.
In step 1, information on the merging path is obtained through communication of the road-vehicle communication unit 5a (FIGS. 1 and 2). Specifically, the starting end x of the merging possible section 15 in FIG._beginAnd terminal x_endGet the information.
In step 2, information from the sensors 1a to 1d constituting the surrounding vehicle detecting means 1 is read.
In step 3, information from the vehicle speed sensor 2a constituting the own vehicle state detecting means 2 is read. The values of x, which is the information of the own vehicle 10 and the surrounding vehicles, are determined by the processes of steps 2 and 3.
In step 4, a default evaluation function is read.
In step 5, an index serving as a criterion for judging merging used in the driving policy determining means 3c is calculated. In the case of the first embodiment, when the merging vehicle 10 maintains the current vehicle speed, the merging end x_endIs calculated by the index calculation unit 3c-1. Is calculated.
In step 6, the index calculated by the index calculation unit 3c-1 in step 5 is compared with the determination logic map 3c-2, and should be merged forward or behind the main line vehicle 11 in the current surrounding environment. A determination is made as to whether or not the person is a child.
In step 7, the evaluation function correction unit 3c-3 determines correction contents of the evaluation function with reference to the determination result in step 6. Specifically, a method of setting a terminal evaluation term (a function ψ for measuring the desirability of the state x of the vehicle group at the predicted terminal time) and a target vehicle speed v of the merged vehicle 10_M ^*Has been described above.
In step 8, from the evaluation function corrected by the evaluation function correction unit 3c-3 of the driving policy determination unit 3c, the evaluation unit 3b, and the preset prediction unit 3a, using the recommended operation amount calculation unit 3d, Calculate the recommended operation amount.
In step 9, on the basis of the recommended operation amount calculated by the recommended operation amount calculation means 3 d, driving support information for the driver is presented on the display device 4.
As described above, in the recommended operation amount generating device for a vehicle according to the first embodiment, the own vehicle state detecting unit 2 that detects the running state of the own vehicle 10 and the surrounding vehicle 11 that runs around the own vehicle 10 are detected. Surrounding vehicle detecting means 1, a lane detecting means 6 for detecting a lane around the own vehicle 10, and a merge end x where a lane capable of traveling around the own vehicle 10 has disappeared._endDetecting means 5 for detecting the vehicle position, predicting means 3a for predicting the future position and speed of each of the vehicles 10 and 11 from the amount of operation that the own vehicle 10 and the surrounding vehicle 11 can take, The evaluation means 3b for numerically evaluating the desirability of the state of the entire vehicle group from the speed, the speed, and the operation amount, and the own vehicle 10 and the vehicle 10 based on the future prediction of the evaluation value calculated by the evaluation means 3b. Recommended operation amount calculating means 3d for calculating a pattern of an acceleration / deceleration operation and a lane changing operation to be taken by the surrounding vehicle 11, a merging vehicle 10 running on a merging lane 13 where the disappearance of the lane is detected, and a merging lane 13 Driving policy determining means 3 for determining whether the merging vehicle 10 should merge in front of or behind the main vehicle 11 based on the position and speed relationship with the main vehicle 11 traveling on the adjacent main lane 12. With the door has a configuration of adding the correction to the evaluation unit 3b according to the calculated result of the operation policy determining means 3c.
As described above, in the first embodiment, the driving policy determination unit 3c determines whether to join the front or the back of the main vehicle 11 traveling on the main lane 12, and the determined result is corrected by the evaluation unit 3b. It is configured to reflect. By introducing the operation policy determining means 3c, it is possible to clarify the judgment on the system side as to how to merge, and by changing the processing contents of the operation policy determining means 3c, various types of drivers can be used. It is possible to reproduce the judgment according to the merging characteristics. In addition, by including a term for suppressing the driver's discomfort in the evaluation term of the evaluation means 3b, the control command for the calculated merging can be controlled in accordance with the determination result of the driving policy determination means 3c. Can be made less uncomfortable for the person. That is, it is possible to calculate a control command that achieves both clarity of behavior and low uncomfortable feeling.
[0037]
In addition, the merging detection means 5 determines the merging end x based on information obtained through road-vehicle communication (road-vehicle communication unit 5a) between the communication device fixed on the road and the communication device mounted on the vehicle 10._endIs detected. As described above, by using the road-vehicle communication, information on the road structure in the merging section can be obtained with high accuracy, so that a more accurate and reliable control command can be calculated.
Further, the driving policy determining means 3c determines that the merging vehicle 10 is at the merging end x_end, The end arrival time TTE, which is a predicted value of the time required to reach the vehicle, the overtaking time TTP, which is the predicted value of the time required for the merged vehicle 10 to be overtaken by the main line vehicle 11, and the Based on the risk evaluation value (risk function RP) expected when the merging vehicle 10 changes lanes to the main lane 12 calculated from the relationship between the relative position and the speed, whether to merge in front of the main lane vehicle is determined. It is configured to determine whether to join. As described above, the current vehicle speed level is maintained by comparing the end arrival time TTE and the overtaking time TTP in the merging lane 13 where the section of the road where merging is possible is not a point but a section having a length. End point x_endIt is possible to determine whether or not there is a chance to join with a margin before reaching the vicinity. That is, in the prior art described in the patent document, the merging point is represented by a point. Therefore, on a road that can merge anywhere in a section having a predetermined spread, the merging point is set in advance. There was a problem that it had to be decided, but the first embodiment can solve this problem. By taking into account the risk RP when the lane is changed to the main lane 12, it is possible to make an appropriate judgment as to whether to accelerate or decelerate in order to realize a marginal merge.
[0038]
In addition, the driving policy determining means 3c should join in front of the main line vehicle 11 when the risk evaluation value is lower than a predetermined level and the terminal arrival time TTE is shorter than the overtaking time TTP by a predetermined value or more. In other cases, it is determined that it should merge backward. In this way, if the current vehicle speed level is maintained, the merging end x_endIs established, and only when there is sufficient margin with the main line vehicle 11, the logic that determines that the vehicle should merge ahead of the main line vehicle 11 is configured. Can be calculated based on the control command.
In addition, the evaluation means 3b calculates the risk evaluation value RP expected when the merging vehicle 10 changes lanes to the main lane 12 and the risk evaluation value RP expected when the merging vehicle 10 stays in the merging lane 13. Is included in the evaluation, and when the risk MP remaining in the merging lane 13 exceeds the risk RP expected when the lane is changed, the lane change is instructed. As described above, the risk MP for staying in the merging lane 13 is introduced, and whether or not merging is possible is determined by comparing with the risk RP expected when merging with the main lane 12, so that the section where merging is possible is determined. Even on a road that can be regarded as a section having a length rather than a point, it is possible to specifically calculate a position and a timing to be merged.
[0039]
Also, the evaluation means 3b determines that the merging vehicle 10 is at the merging end x_end, The risk evaluation value RP is set to be larger. Thus, the junction end x_end, The risk MP of staying in the merging lane 13 is greatly estimated, so that the merging end x_end, It becomes easier to obtain a control command for instructing merging, and the merging end x_endIt is possible to suppress the generation of a control command that reaches the control command.
[0040]
Further, the evaluation means 3b calculates the assumed value v of the desired traveling vehicle speed of each of the vehicles 10 and 11._T ^*, V_M ^*Is included in the evaluation, and the expected value v of the desired traveling speed of each of the vehicles 10 and 11 is included in the evaluation._T ^*, V_M ^*Is corrected on the basis of the driving policy determined by the driving policy determining means 3c. As described above, since the determination regarding the driving policy is reflected in the calculation of the control command through the parameter of the desired traveling vehicle speed, the determination result of the driving policy determining means is controlled only by a simple mathematical operation of changing the parameter. It can be reflected in the calculation result of the command.
[0041]
The above is the first embodiment of the present invention.
[0042]
Embodiment 2
Second Embodiment A second embodiment of the present invention will be described with reference to FIGS.
FIG. 9 is a layout diagram necessary for configuring the vehicle recommended operation amount generation device according to the second embodiment. The basic configuration is the same as that of the first embodiment. The only difference is that the merging detection means 5 (see FIG. 2) is not a road-to-vehicle communication unit (5a in FIG. 1) but a navigation system 5b. It is that you are. That is, in the second embodiment, information on the merging lane is obtained not from the road-vehicle communication but from the navigation system 5b. The configuration of the arithmetic unit 3 and the processing of each block in the first embodiment shown in FIG. 2 are exactly the same in the second embodiment.
[0043]
The operation of the apparatus in the scene of FIG. 10 will be described. FIG. 10 is the same scene as FIG. 3 which is an example of the application scene of Embodiment 1, except that the own vehicle and the other vehicle are replaced. In FIG. 10, 10a is a main line vehicle (own vehicle), and 11a is a merging vehicle (other vehicle).
In FIG. 10, the own vehicle 10a obtains the current value information and the information of the map information database from the navigation system 5b, and the lane on the right side of the main lane 12, which is the traveling lane of the own vehicle 10a, is the merging lane 13, and the own vehicle 10a It is detected that the vehicle 10a joins the main lane 12 of the vehicle. That is, it is determined that the vehicle traveling on the merging lane 13 on the right side of the vehicle 10a is the merging vehicle 11a.
Subsequent processing proceeds in exactly the same manner as in the first embodiment, and the recommended operation amount is u_x ^T(Τ), u_x ^M(Τ), u_y ^M(Τ), t ≦ τ ≦ t + T is calculated.
As the information to be presented to the driver, the same type as in the first embodiment can be used. For example, the display content of the display device 4 in the scene of FIG. 10 is as shown in FIG.
As described above, in the second embodiment, the merging detection means (see 5 in FIG. 2) determines the merging end x based on the information on the road structure obtained from the navigation system 5b (FIG. 9)._endIs detected. Therefore, by collating the information on the current position obtained from the navigation system 5b with the information on the road structure recorded in the map information database, it is possible to determine which lane corresponds to the merging lane disappearing in front. be able to.
[0044]
The above is the second embodiment of the present invention.
[0045]
Embodiment 3
Third Embodiment A third embodiment of the present invention will be described with reference to FIGS.
The layout of the third embodiment is the same as that of the second embodiment shown in FIG. However, the navigation system 5b according to the third embodiment has a function of receiving not only GPS signals but also signals related to road information such as FM multiplex broadcasting.
FIG. 12 shows an example of an application scene of the third embodiment. FIG. 12 shows a scene in which the own vehicle 10 is traveling in the right lane and another vehicle 11 is traveling behind the left lane. In the third embodiment, information on a regulated lane (regulated lane 17) associated with road construction, an accident, or the like is received, and when the own vehicle 10 approaches the corresponding point, the regulated lane 17 is combined with the merged lane. It is assumed that the recommended operation amount is presented to the driver. In the right lane (restriction lane 17) in front of the own vehicle 10, lane regulation is performed due to an accident, and the lane has virtually disappeared. In the third embodiment, such lane regulation information is detected by receiving a road information signal. The restricted lane is considered to be the same type of lane as the merging lane in the first and second embodiments, and a virtual merging end x is set at an appropriate point before lane regulation is performed._endSet. In that way, the junction end x_endIs set, mathematically, the problem of generating the recommended operation amount becomes exactly the same as that of the first and second embodiments. Can be.
As the information to be presented to the driver, the same type as in the first and second embodiments can be used. For example, the display content of the display device 4 in the scene of FIG. 12 is as shown in FIG.
[0046]
As described above, in the third embodiment, the merging detecting means (see 5 in FIG. 2) determines the merging end x based on the information on the accident and the road construction obtained by receiving the radio broadcasting such as the FM multiplex broadcasting._endIs detected. Therefore, by taking in information on lane regulation due to accidents, construction, and the like provided by wireless broadcasting, information on the vanishing point of the lane, which cannot be grasped only by the map information database, can be obtained, and it is possible to cope with more various scenes.
[0047]
The above is the third embodiment of the present invention.
[0048]
Although the present invention has been specifically described based on the embodiments, the present invention is not limited to the above-described embodiments, and it is needless to say that various modifications can be made without departing from the gist of the present invention.
[Brief description of the drawings]
FIG. 1 is a layout diagram of a vehicle recommended operation amount generation device according to a first embodiment of the present invention.
FIG. 2 is a diagram illustrating a configuration of functional blocks of the device according to the first embodiment of the present invention.
FIG. 3 is a diagram showing an example of an application scene of the first embodiment of the present invention.
FIG. 4 is a diagram showing an example of a risk function for staying in a merging lane according to Embodiment 1 of the present invention.
FIG. 5 is a block diagram of an operation policy determination unit according to the first embodiment of the present invention.
FIG. 6 is a diagram illustrating an example of a determination logic map in an operation policy determination unit according to the first embodiment of the present invention.
FIG. 7 is a diagram illustrating an example of a calculation result of a recommended operation amount and a display method thereof according to the first embodiment of the present invention.
FIG. 8 is a diagram showing a flowchart of a process according to the first embodiment of the present invention.
FIG. 9 is a layout diagram of a vehicle recommended operation amount generation device according to a second embodiment of the present invention.
FIG. 10 is a diagram showing an example of an application scene of the second embodiment of the present invention.
FIG. 11 is a diagram illustrating an example of a calculation result of a recommended operation amount and a display method thereof according to the second embodiment of the present invention.
FIG. 12 is a diagram illustrating an example of an application scene of a third embodiment of the present invention.
FIG. 13 is a diagram illustrating an example of a calculation result of a recommended operation amount and a display method thereof according to the third embodiment of the present invention.
[Explanation of symbols]
1. Surrounding vehicle detection means
1a ... Forward radar
1b ... Image sensor
1c ... rear radar
1d ... side sensor
2. Vehicle status detection means
2a: Vehicle speed sensor
3. Calculation part
3a: prediction means
3b ... Evaluation means
3c: Operating policy decision means
3c-1 ... Index calculation unit
3c-2: Decision logic map
3c-3 ... Evaluation function correction unit
3d: Recommended operation amount calculation means
3f… Ambient environment information
3g… Correction contents
4. Display device
5 ... Merging detection means
5a: Road-to-vehicle communication unit
5b… Navigation system
6 ... Lane detection means
6a ...
10 ... Merging vehicle (own vehicle)
10a: Main line vehicle (own vehicle)
11: Main line vehicles (other vehicles)
11b ... Merging vehicle (other vehicle)
12: Main line lane
13 ... Merging lane
14 ... Unmerged section
15 ... Section where merging is possible
16: Merging completion section
17: Regulated lane

Claims (9)

Own-vehicle state detection means for detecting a running state of the own vehicle;
Surrounding vehicle detecting means for detecting a surrounding vehicle traveling around the own vehicle,
Lane detecting means for detecting a lane around the own vehicle,
Merging detection means for detecting a merging end where a lane capable of traveling around the own vehicle has disappeared,
Prediction means for predicting the future position and speed of each vehicle from the amount of operation that the own vehicle and the surrounding vehicles can take;
Evaluation means for numerically evaluating the desirability of the state of the entire vehicle group from the position of the own vehicle and the surrounding vehicles, the speed, and the operation amount,
Recommended operation amount calculation means for calculating a pattern of acceleration / deceleration operation and lane change operation to be taken by the own vehicle and the surrounding vehicles based on a future prediction of an evaluation value calculated by the evaluation means,
From the position and speed relationship between the merging vehicle traveling on the merging lane where the disappearance of the lane has been detected and the main lane traveling on the main lane adjacent to the merging lane, the merging vehicle moves forward of the main lane. Operating policy decision means for deciding whether to merge or to merge backward,
A recommended operation amount generating device for a vehicle, wherein a correction is made to the evaluation means according to a calculation result of the driving policy determination means. The merging detection means,
The recommended operation for a vehicle according to claim 1, wherein the merging end is detected based on information obtained through road-to-vehicle communication between a communication device fixed on a road and a communication device mounted on the vehicle. Quantity generator. The merging detection means,
The recommended operation amount generating device for a vehicle according to claim 1, wherein the merging end is detected based on information on a road structure obtained from a navigation system. The merging detection means,
The recommended operation amount generating device for a vehicle according to any one of claims 1 to 3, wherein the merging end is detected based on information on an accident and road construction obtained by receiving a radio broadcast. The driving policy determining means,
The terminal arrival time is a predicted value of the time until the merging vehicle reaches the merging terminal,
An overtaking time, which is a predicted value of a time until the merging vehicle is overtaken by the main line vehicle,
An evaluation value of a risk expected when the merged vehicle is changed from the lane to the main lane, which is calculated from the relationship between the relative position and the speed of the merged vehicle and the main line vehicle,
The recommended operation amount generating device for a vehicle according to any one of claims 1 to 4, wherein it is determined whether to merge in front of or behind the main line vehicle based on the following. The driving policy determining means,
The evaluation value of the risk is lower than a predetermined level,
When the terminal arrival time is shorter than the overtaking time by a predetermined value or more, it is determined that the vehicle should join the front of the main line vehicle, and otherwise, it should be determined that the vehicle should join the rear. The recommended operation amount generating device for a vehicle according to claim 5, wherein The evaluation means,
The evaluation value of the risk expected when the merging vehicle has changed lanes to the main lane, and the evaluation includes a comparison between the evaluation value of the risk expected by the merging vehicle staying in the merging lane,
The vehicle recommended operation amount generating device according to any one of claims 1 to 6, wherein a lane change is instructed when a risk of staying in the merging lane exceeds a risk expected when the lane is changed. The evaluation means,
8. The recommended operation amount generating device for a vehicle according to claim 7, wherein the evaluation value of the risk is set to be larger as the merging vehicle approaches the merging end. The evaluation means,
Include the deviation between the assumed value of the desired traveling speed of each vehicle and the actual traveling speed in the evaluation,
The recommended operation amount generating device for a vehicle according to any one of claims 1 to 8, wherein the assumed value of the desired traveling vehicle speed of each vehicle is corrected based on the driving policy determined by the driving policy determining means.

Images