JPH1191538A - Estimation method for wheel friction circle radius - Google Patents
Estimation method for wheel friction circle radiusInfo
- Publication number
- JPH1191538A JPH1191538A JP27644897A JP27644897A JPH1191538A JP H1191538 A JPH1191538 A JP H1191538A JP 27644897 A JP27644897 A JP 27644897A JP 27644897 A JP27644897 A JP 27644897A JP H1191538 A JPH1191538 A JP H1191538A
- Authority
- JP
- Japan
- Prior art keywords
- wheel
- wheels
- force
- vehicle
- driving
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Granted
Links
Landscapes
- Control Of Driving Devices And Active Controlling Of Vehicle (AREA)
- Regulating Braking Force (AREA)
- Control Of Vehicle Engines Or Engines For Specific Uses (AREA)
Abstract
Description
【0001】[0001]
【発明の属する技術分野】本発明は、車輪の摩擦円半径
の推定方法に係り、更に詳細には各輪毎に摩擦円半径を
推定する方法に係る。The present invention relates to a method for estimating the radius of a friction circle of a wheel, and more particularly to a method of estimating a radius of a friction circle for each wheel.
【0002】[0002]
【従来の技術】自動車等の車輌に於ける車輪の摩擦円半
径の推定方法の一つとして、例えば本願出願人の出願に
かかる特開平4−331668号公報に記載されている
如く、車輌の前後加速度及び横加速度を検出し、車輪の
スリップが発生した際の前後加速度及び横加速度の二乗
和平方根を車輪の摩擦円半径と推定する方法が従来より
知られている。2. Description of the Related Art As one of methods for estimating the radius of a friction circle of a wheel in a vehicle such as an automobile, for example, as described in Japanese Patent Application Laid-Open No. Hei 4-331668 filed by the present applicant, the front and rear of the vehicle are described. 2. Description of the Related Art A method of detecting acceleration and lateral acceleration and estimating a root-sum-square of longitudinal acceleration and lateral acceleration when a wheel slip occurs as a friction circle radius of a wheel has been conventionally known.
【0003】車輪がスリップしているときに路面と車輌
との間に作用する水平方向の力は路面の摩擦係数に比例
し、水平方向の力は車輌の前後加速度及び横加速度の二
乗和平方根に比例するので、上述の方法によれば、路面
の摩擦係数に対応する値として車輪の摩擦円半径を推定
することができる。[0003] The horizontal force acting between the road surface and the vehicle when the wheel is slipping is proportional to the friction coefficient of the road surface, and the horizontal force is calculated as the root-sum-square of the longitudinal acceleration and the lateral acceleration of the vehicle. Since it is proportional, according to the above-described method, it is possible to estimate the friction circle radius of the wheel as a value corresponding to the friction coefficient of the road surface.
【0004】[0004]
【発明が解決しようとする課題】しかし上述の先の提案
にかかる従来の摩擦円半径の推定方法に於いては、車輌
全体の水平方向の力に基づき車輪の摩擦円半径が推定さ
れるので、路面の摩擦係数に対応する値を求めることは
できるが、各輪毎に個別に摩擦円半径を推定することが
できないという問題がある。However, in the conventional method of estimating the radius of the friction circle according to the above-mentioned proposal, the radius of the friction circle of the wheel is estimated based on the horizontal force of the entire vehicle. Although it is possible to obtain a value corresponding to the friction coefficient of the road surface, there is a problem that the friction circle radius cannot be individually estimated for each wheel.
【0005】本発明は、従来の減衰力制御装置従来の摩
擦円半径の推定方法に於ける上述の如き問題に鑑みてな
されたものであり、本発明の主要な課題は、各輪毎に路
面と車輪との間に作用する水平方向の力を推定すること
により、各輪毎に個別に摩擦円半径を正確に推定するこ
とである。The present invention has been made in view of the above-mentioned problems in the conventional method of estimating the radius of the friction circle in the conventional damping force control apparatus. By estimating the horizontal force acting between the wheel and the wheel, the friction circle radius is accurately estimated individually for each wheel.
【0006】[0006]
【課題を解決するための手段】上述の如き主要な課題
は、本発明によれば、請求項1の構成、即ち車輪の摩擦
円半径を推定する方法にして、各輪の横力を推定する工
程と、各輪の前後力を推定する工程と、各輪毎に前記横
力及び前記前後力の二乗和平方根を演算する工程と、各
輪毎に車輪スリップを検出する工程と、各輪毎に車輪ス
リップが検出されたときの前記二乗和平方根を当該車輪
の摩擦円半径と推定する工程とを有することを特徴とす
る方法によって達成される。According to the present invention, there is provided a method for estimating a radius of a friction circle of a wheel according to the present invention, wherein lateral force of each wheel is estimated. A step of estimating the longitudinal force of each wheel, a step of calculating the root-sum-square of the lateral force and the longitudinal force of each wheel, a step of detecting a wheel slip for each wheel, Estimating the root-sum-square when the wheel slip is detected as the friction circle radius of the wheel.
【0007】上記請求項1の構成によれば、各輪毎に横
力及び前後力の二乗和平方根が演算され、各輪毎に車輪
スリップが検出されたときの二乗和平方根が当該車輪の
摩擦円半径と推定されるので、路面と各輪との間に作用
する水平方向の力に基づき各輪毎に個別に摩擦円半径が
正確に推定される。According to the first aspect of the present invention, the root-sum-square of the lateral force and the longitudinal force is calculated for each wheel, and the root-sum-square when wheel slip is detected for each wheel is determined by the friction of the wheel. Since the circle radius is estimated, the friction circle radius is accurately estimated individually for each wheel based on the horizontal force acting between the road surface and each wheel.
【0008】また本発明によれば、上述の主要な課題を
効果的に達成すべく、上記請求項1の構成に於て、前記
車輪は駆動輪であり、前記前後力を推定する工程は左右
駆動輪の合計の駆動力を演算する工程と、左右駆動輪の
制駆動力差及び左右駆動輪の車輪回転慣性力差に基づき
左右駆動輪の駆動力差を演算する工程と、前記合計の駆
動力及び前記駆動力差に基づき各駆動輪の前後力を演算
する工程とを含むよう構成される(請求項2の構成)。According to the present invention, in order to effectively achieve the above-mentioned main object, in the above-mentioned structure of the first aspect, the wheel is a driving wheel, and the step of estimating the front-rear force includes the right and left. Calculating the total driving force of the driving wheels; calculating the driving force difference between the left and right driving wheels based on the braking / driving force difference between the left and right driving wheels and the wheel rotational inertia force difference between the left and right driving wheels; Calculating the longitudinal force of each driving wheel based on the force and the driving force difference (the configuration according to claim 2).
【0009】この請求項2の構成によれば、左右駆動輪
の合計の駆動力が演算され、左右駆動輪の制駆動力差及
び左右駆動輪の車輪回転慣性力差に基づき左右駆動輪の
駆動力差が演算され、合計の駆動力及び駆動力差に基づ
き各駆動輪の前後力が演算されるので、各駆動輪の前後
力が正確に推定される。According to this configuration, the total driving force of the left and right driving wheels is calculated, and the driving of the left and right driving wheels is performed based on the braking / driving force difference between the left and right driving wheels and the wheel rotational inertia difference between the left and right driving wheels. The force difference is calculated, and the longitudinal force of each driving wheel is calculated based on the total driving force and the driving force difference, so that the longitudinal force of each driving wheel is accurately estimated.
【0010】また本発明によれば、上述の主要な課題を
効果的に達成すべく、上記請求項2の構成に於て、前記
左右駆動輪は後輪駆動車の左右後輪又は前輪駆動車の左
右前輪であり、前記左右駆動輪の合計の駆動力は車輌の
前後加速度と車輌の重量との積として演算されるよう構
成される(請求項3の構成)。According to the present invention, in order to effectively achieve the above-mentioned main object, in the structure of the above-mentioned claim 2, the left and right drive wheels may be left and right rear wheels of a rear wheel drive vehicle or a front wheel drive vehicle. And the total driving force of the left and right driving wheels is calculated as a product of the longitudinal acceleration of the vehicle and the weight of the vehicle.
【0011】一般に、車輌が後輪駆動車又は前輪駆動車
である場合には、車輌の前後加速度は左右駆動輪の合計
の駆動力に等しい。上記請求項3の構成によれば、車輌
の前後加速度と車輌の重量との積が左右駆動輪の合計の
駆動力として演算されるので、左右駆動輪の合計の駆動
力が確実に推定される。Generally, when the vehicle is a rear wheel drive vehicle or a front wheel drive vehicle, the longitudinal acceleration of the vehicle is equal to the total driving force of the left and right drive wheels. According to the configuration of the third aspect, since the product of the longitudinal acceleration of the vehicle and the weight of the vehicle is calculated as the total driving force of the left and right driving wheels, the total driving force of the left and right driving wheels is reliably estimated. .
【0012】また本発明によれば、上述の主要な課題を
効果的に達成すべく、上記請求項2の構成に於て、前記
左右駆動輪は後輪駆動車の左右後輪又は前輪駆動車の左
右前輪であり、前記左右駆動輪の合計の駆動力はトルク
コンバータの出力トルクに基づき演算されるよう構成さ
れる(請求項4の構成)。According to the present invention, in order to effectively achieve the above-mentioned main object, in the configuration of the above-mentioned claim 2, the left and right drive wheels may be left and right rear wheels of a rear wheel drive vehicle or a front wheel drive vehicle. And the total driving force of the left and right driving wheels is calculated based on the output torque of a torque converter.
【0013】左右駆動輪はトルクコンバータの出力トル
クにより駆動されるので、左右駆動輪の合計の駆動力は
トルクコンバータの出力トルクに対応している。上記請
求項4の構成によれば、トルクコンバータの出力トルク
に基づき左右駆動輪の合計の駆動力が演算されるので、
左右駆動輪の合計の駆動力が確実に推定される。Since the left and right driving wheels are driven by the output torque of the torque converter, the total driving force of the left and right driving wheels corresponds to the output torque of the torque converter. According to the configuration of the fourth aspect, the total driving force of the left and right driving wheels is calculated based on the output torque of the torque converter.
The total driving force of the left and right driving wheels is reliably estimated.
【0014】[0014]
【課題解決手段の好ましい態様】本発明の一つの好まし
い態様によれば、上記請求項1の構成に於いて、車輌の
ヨーレート及び横加速度に基づき左右前輪の横力の合計
及び左右後輪の横力の合計が演算され、車輌の前後加速
度及び横加速度に基づき各輪の垂直荷重が演算され、各
輪の横力がその車輪の垂直荷重に比例する値として演算
されるよう構成される(好ましい態様1)。According to a preferred aspect of the present invention, in the configuration of the first aspect, the sum of the lateral forces of the left and right front wheels and the lateral force of the right and left rear wheels are determined based on the yaw rate and the lateral acceleration of the vehicle. The sum of the forces is calculated, the vertical load of each wheel is calculated based on the longitudinal acceleration and the lateral acceleration of the vehicle, and the lateral force of each wheel is calculated as a value proportional to the vertical load of the wheel (preferable). Aspect 1).
【0015】本発明の他の一つの好ましい態様によれ
ば、上記請求項1の構成に於いて、一方の駆動輪の前後
力は合計の駆動力より駆動力差が減算された値の二分の
一として演算され、他方の駆動輪の前後力は一方の駆動
輪の前後力と駆動力差との和として演算されるよう構成
される(好ましい態様2)。According to another preferred aspect of the present invention, in the configuration of the first aspect, the longitudinal force of one of the driving wheels is a half of a value obtained by subtracting the driving force difference from the total driving force. It is configured to be calculated as one, and the longitudinal force of the other driving wheel is calculated as the sum of the longitudinal force of one driving wheel and the driving force difference (preferred mode 2).
【0016】本発明の他の一つの好ましい態様によれ
ば、上記請求項3又は4の構成に於いて、左右駆動輪の
合計の駆動力は車輌の前後加速度と車輌の重量との積と
して演算される駆動力及びトルクコンバータの出力トル
クに基づき演算される駆動力の平均値として演算される
よう構成される(好ましい態様3)。According to another preferred embodiment of the present invention, in the configuration of claim 3 or 4, the total driving force of the left and right driving wheels is calculated as a product of the longitudinal acceleration of the vehicle and the weight of the vehicle. It is configured to be calculated as an average value of the driving force calculated based on the driving force and the output torque of the torque converter (preferred mode 3).
【0017】本発明の他の一つの好ましい態様によれ
ば、上記好ましい態様3の構成に於いて、変速中及び変
速後の所定の時間はトルクコンバータの出力トルクに基
づき演算される駆動力は0に設定されるよう構成される
(好ましい態様4)。According to another preferred embodiment of the present invention, in the configuration of the above-mentioned preferred embodiment 3, the driving force calculated based on the output torque of the torque converter is 0 during a predetermined time during and after a shift. (Preferred mode 4).
【0018】[0018]
【発明の実施の形態】以下に添付の図を参照しつつ、本
発明を好ましい実施形態について詳細に説明する。DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Preferred embodiments of the present invention will be described below in detail with reference to the accompanying drawings.
【0019】図1は自動変速機が搭載され本発明に従っ
て左右後輪の摩擦円半径が推定される後輪駆動車を示す
概略構成図(A)及び制御系のブロック線図(B)であ
る。FIG. 1 is a schematic configuration diagram (A) showing a rear wheel drive vehicle equipped with an automatic transmission and in which the friction circle radii of the left and right rear wheels are estimated according to the present invention, and a block diagram (B) of a control system. .
【0020】図1に於いて、10はエンジンを示してお
り、エンジン10の駆動力はトルクコンバータ12及び
トランスミッション14を含む自動変速機16を介して
プロペラシャフト18へ伝達される。プロペラシャフト
18の駆動力はディファレンシャル20により左後輪車
軸22L 及び右後輪車軸22R へ伝達され、これにより
駆動輪である左右の後輪24RL及び24RRが回転駆動さ
れる。In FIG. 1, reference numeral 10 denotes an engine, and a driving force of the engine 10 is transmitted to a propeller shaft 18 via an automatic transmission 16 including a torque converter 12 and a transmission 14. The driving force of the propeller shaft 18 is transmitted to the left rear wheel axle 22L and the right rear wheel axle 22R by the differential 20, whereby the left and right rear wheels 24RL and 24RR, which are the driving wheels, are driven to rotate.
【0021】一方左右の前輪24FL及び24FRは従動輪
であると共に操舵輪であり、図1には示されていない
が、運転者によるステアリングホイールの転舵に応答し
て駆動されるラック・アンド・ピニオン式のパワーステ
アリング装置によりタイロッドを介して操舵される。On the other hand, the left and right front wheels 24FL and 24FR are both driven wheels and steering wheels, and although not shown in FIG. 1, a rack-and-wheel driven in response to the driver turning the steering wheel. It is steered via a tie rod by a pinion type power steering device.
【0022】左右の前輪24FL、24FR及び左右の後輪
24RL、24RRの制動力は制動装置26の油圧回路28
により対応するホイールシリンダ30FL、30FR、30
RL、30RRの制動圧が制御されることによって制御され
る。図には示されていないが、油圧回路28はリザー
バ、オイルポンプ、種々の弁装置等を含み、各ホイール
シリンダの制動圧は通常時には運転者によるブレーキペ
ダル32の踏み込み操作に応じて駆動されるマスタシリ
ンダ34により制御され、また必要に応じて後に詳細に
説明する如く車輌運動制御コンピュータ36により制御
される。The braking force of the left and right front wheels 24FL, 24FR and the left and right rear wheels 24RL, 24RR is controlled by a hydraulic circuit 28 of the braking device 26.
Wheel cylinders 30FL, 30FR, 30
It is controlled by controlling the braking pressure of RL and 30RR. Although not shown in the drawing, the hydraulic circuit 28 includes a reservoir, an oil pump, various valve devices, and the like, and the braking pressure of each wheel cylinder is normally driven in response to the driver's depressing operation of the brake pedal 32. It is controlled by a master cylinder 34 and, if necessary, by a vehicle motion control computer 36 as will be described in detail later.
【0023】車輌運動制御コンピュータ42には前後加
速度センサ38より車輌の前後加速度Gx を示す信号、
横加速度センサ40より車輌の横加速度Gy を示す信
号、車速センサ42より車速Vを示す信号、ヨーレート
センサ44より車輌のヨーレートγを示す信号、車輪速
度センサ46RL、46RRより左右後輪の車輪速度Vwr
l、Vwrr を示す信号、圧力センサ48RL、48RRより
左右後輪のホイールシリンダ30RL、30RR内の圧力P
rl及びPrrを示す信号、シフトポジションセンサ50よ
り自動変速機16のシフトポジションSPを示す信号、
回転数センサ52よりエンジン回転数Ne を示す信号、
回転数センサ54よりトルクコンバータ12の出力回転
数Nout を示す信号が入力される。A signal indicating the longitudinal acceleration Gx of the vehicle is sent from the longitudinal acceleration sensor 38 to the vehicle motion control computer 42.
A signal indicating the lateral acceleration Gy of the vehicle from the lateral acceleration sensor 40, a signal indicating the vehicle speed V from the vehicle speed sensor 42, a signal indicating the yaw rate γ of the vehicle from the yaw rate sensor 44, and the wheel speeds Vwr of the left and right rear wheels from the wheel speed sensors 46RL and 46RR.
l, the signal indicating Vwrr and the pressure P in the left and right rear wheel cylinders 30RL, 30RR from the pressure sensors 48RL, 48RR.
signals indicating rl and Prr, a signal indicating the shift position SP of the automatic transmission 16 from the shift position sensor 50,
A signal indicating the engine speed Ne from the speed sensor 52;
A signal indicating the output rotation speed Nout of the torque converter 12 is input from the rotation speed sensor 54.
【0024】尚車輌運動制御コンピュータ36は実際に
はCPU、ROM、RAM、入出力ポート装置を含む周
知の構成のマイクロコンピュータであってよい。また前
後加速度センサ38は車輌の加速方向を正として前後加
速度を検出し、横加速度センサ40及びヨーレートセン
サ44は車輌の左旋回方向を正として横加速度等を検出
するようになっている。更に左右後輪のホイールシリン
ダ30RL、30RR内の圧力Prl及びPrrは例えばマスタ
シリンダ34内の圧力等に基づき推定されてもよい。The vehicle motion control computer 36 may be a microcomputer having a known configuration including a CPU, a ROM, a RAM, and an input / output port device. The longitudinal acceleration sensor 38 detects longitudinal acceleration with the acceleration direction of the vehicle as positive, and the lateral acceleration sensor 40 and the yaw rate sensor 44 detects lateral acceleration and the like with the left turning direction of the vehicle as positive. Further, the pressures Prl and Prr in the wheel cylinders 30RL and 30RR of the left and right rear wheels may be estimated based on, for example, the pressure in the master cylinder 34 and the like.
【0025】フローチャートとしては図示されていない
が、車輌運動制御コンピュータ36は車速Vに基づき駆
動輪である左右の後輪24RL及び24RRの目標車輪速度
Vwtを演算し、実車輪速度と目標車輪速度との偏差とし
て左右後輪の駆動スリップ量SLrl及びSLrrを演算
し、駆動スリップ量SLrl及びSLrrに比例する値とし
て左右後輪の目標制動力Ftrl 及びFtrr を演算し、左
右後輪の制動力がそれぞれ対応する目標制動力になるよ
うホイールシリンダ30RL、30RR内の圧力を制御す
る。Although not shown in the flowchart, the vehicle motion control computer 36 calculates the target wheel speeds Vwt of the left and right rear wheels 24RL and 24RR as drive wheels based on the vehicle speed V, and calculates the actual wheel speed, the target wheel speed, The driving slip amounts SLrl and SLrr of the left and right rear wheels are calculated as the deviations of the left and right rear wheels, and the target braking forces Ftrl and Ftrr of the left and right rear wheels are calculated as values proportional to the driving slip amounts SLrl and SLrr. The pressure in the wheel cylinders 30RL and 30RR is controlled so as to achieve the corresponding target braking force.
【0026】また車輌運動制御コンピュータ36は前後
加速度Gx に基づく左右後輪の前後力Fxgrl、Fxgrrを
演算し、トルクコンバータの出力トルクに基づく左右後
輪の前後力Fxtrl、Fxtrrを演算し、それらの平均値と
して左右後輪の前後力Fxrl、Fxrr を演算する。また
コンピュータ36は四輪の接地荷重Fzjを演算し、接地
荷重に基づき四輪のコーナリングフォースFyjを演算
し、左右後輪の前後力Fxrl 、Fxrr 及びコーナリング
フォースFyrl 、Fyrr の二乗和平方根として左右後輪
の摩擦円半径Rmrl 、Rmrr を演算する。The vehicle motion control computer 36 calculates the longitudinal forces Fxgrl and Fxgrr of the left and right rear wheels based on the longitudinal acceleration Gx, and calculates the longitudinal forces Fxtrl and Fxtrr of the right and left rear wheels based on the output torque of the torque converter. The longitudinal force Fxrl, Fxrr of the left and right rear wheels is calculated as an average value. The computer 36 also calculates the four-wheel contact load Fzj, calculates the four-wheel cornering force Fyj based on the contact load, and calculates the front-rear force Fxrl, Fxrr of the left and right rear wheels and the square root of the sum of squares of the cornering forces Fyrl, Fyrr. The wheel friction circle radii Rmrl and Rmrr are calculated.
【0027】この場合駆動スリップ量SLrl及びSLrr
に比例する値として演算される左右後輪の目標制動力F
trl 及びFtrr がそれぞれ摩擦円半径Rmrl 、Rmrr に
照らし過剰であるときには、車輌運動制御コンピュータ
36は目標制動力を摩擦円半径にてガード処理し、左右
後輪の制動力が過剰になることを防止して左右後輪のト
ラクションを最適に制御する。In this case, the driving slip amounts SLrl and SLrr
Target braking force F for the left and right rear wheels calculated as a value proportional to
When trl and Ftrr are excessive in light of the friction circle radii Rmrl and Rmrr, respectively, the vehicle motion control computer 36 performs a guard process on the target braking force based on the friction circle radius to prevent the braking force of the left and right rear wheels from becoming excessive. To optimally control the traction of the left and right rear wheels.
【0028】次に図2に示されたフローチャートを参照
して図示の実施形態に於ける車輪の摩擦円半径演算のメ
インルーチンについて説明する。尚図2に示されたフロ
ーチャートによる演算は図には示されていないイグニッ
ションスイッチの閉成により開始され、所定の時間毎に
繰返し実行される。Next, a main routine for calculating a friction circle radius of a wheel in the illustrated embodiment will be described with reference to a flowchart shown in FIG. The calculation according to the flowchart shown in FIG. 2 is started by closing an ignition switch (not shown), and is repeatedly executed at predetermined time intervals.
【0029】まずステップ10に於いては、車輌の前後
加速度Gx を示す信号等の読み込みが行われ、ステップ
20に於いては、図3に示されたサブルーチンに従って
前後加速度Gx に基づく左右後輪の前後力Fxgrl、Fxg
rrが演算され、ステップ30に於いては、図4に示され
たサブルーチンに従ってトルクコンバータ12の出力ト
ルクに基づく左右後輪の前後力Fxtrl、Fxtrrが演算さ
れる。First, in step 10, a signal indicating the longitudinal acceleration Gx of the vehicle is read, and in step 20, the left and right rear wheels based on the longitudinal acceleration Gx are read in accordance with the subroutine shown in FIG. Front and rear force Fxgrl, Fxg
rr is calculated, and in step 30, the longitudinal forces Fxtrl and Fxtrr of the left and right rear wheels based on the output torque of the torque converter 12 are calculated according to a subroutine shown in FIG.
【0030】ステップ40に於いては、図5に示された
サブルーチンに従って四輪の接地荷重Fzj(j=fl、f
r、rl、rr)が演算され、ステップ50に於いては、図
6に示されたサブルーチンに従って四輪のコーナリング
フォースFyj(j=fl、fr、rl、rr)が演算される。In step 40, the ground contact load Fzj (j = fl, f) of the four wheels according to the subroutine shown in FIG.
r, rl, rr) are calculated, and in step 50, the four-wheel cornering force Fyj (j = fl, fr, rl, rr) is calculated according to the subroutine shown in FIG.
【0031】ステップ60に於いては、シフトポジショ
ンセンサ50よりのSP信号に基づき自動変速機16が
変速中であるか否かの判別、即ち自動変速機の変速段の
切り換え中又は変速段の切り換え完了後の所定の時間内
であり、左右後輪の駆動力が安定しない期間中であるか
否かの判別が行われ、否定判別が行われたときにはステ
ップ70に於いてステップ90の演算に於ける重み係数
Kx が1に設定され、肯定判別が行われたときにはステ
ップ80に於いて重み係数Kx が0に設定される。In step 60, it is determined whether or not the automatic transmission 16 is shifting gears based on the SP signal from the shift position sensor 50, that is, during or during gear shift of the automatic transmission. It is determined whether or not it is within a predetermined time after completion and during a period during which the driving force of the left and right rear wheels is not stable, and if a negative determination is made, the process proceeds to step 70 in step 90. The weighting coefficient Kx is set to 1 and when a positive determination is made, the weighting coefficient Kx is set to 0 in step 80.
【0032】ステップ90に於いては、前後加速度Gx
に基づく前後力Fxgrl、Fxgrrとトルクコンバータの出
力トルクに基づく前後力Fxtrl、Fxtrrとの重み平均値
として下記の数1に従って左右後輪の前後力Fxrl 、F
xrr が演算され、ステップ100に於いては、図7に示
されたサブルーチンに従って左右後輪の摩擦円半径Rmr
l 、Rmrr が演算される。In step 90, the longitudinal acceleration Gx
The longitudinal force Fxrl, Fx of the left and right rear wheels according to the following equation 1 as a weighted average value of the longitudinal force Fxgrl, Fxgrr based on the torque and the longitudinal force Fxtrl, Fxtrr based on the output torque of the torque converter.
xrr is calculated, and in step 100, the friction circle radius Rmr of the left and right rear wheels according to the subroutine shown in FIG.
l and Rmrr are calculated.
【数1】Fxrl =(Fxgrl+Kx ・Fxtrl)/2 Fxrr =(Fxgrr+Kx ・Fxtrr)/2## EQU1 ## Fxrl = (Fxgrl + Kx.Fxtrl) / 2 Fxrr = (Fxgrr + Kx.Fxtrr) / 2
【0033】図3に示された左右後輪の前後力Fxgrl、
Fxgrr演算ルーチンのステップ21に於いては、Mを車
輌の重量として下記の数2に従って左右後輪の合計の前
後力Fxallが演算され、ステップ22に於いては、Cpf
をブレーキ油圧より前後力への変換係数として下記の数
3に従って左右後輪の制動力についての補正値Fxbrl、
Fxbrrが演算される。The longitudinal force Fxgrl of the left and right rear wheels shown in FIG.
In step 21 of the Fxgrr calculation routine, the total longitudinal force Fxall of the left and right rear wheels is calculated in accordance with the following equation (2), where M is the weight of the vehicle. In step 22, Cpf
Is a correction coefficient Fxbrl for the braking force of the left and right rear wheels according to the following Equation 3 as a conversion coefficient from the brake hydraulic pressure to the longitudinal force.
Fxbrr is calculated.
【0034】[0034]
【数2】Fxall=M・Gx## EQU2 ## Fxall = M · Gx
【数3】Fxbrl=Cpf ・Prl Fxbrr=Cpf ・Prr## EQU3 ## Fxbrl = Cpf.Prl Fxbrr = Cpf.Prr
【0035】ステップ23に於いては、左右後輪の車輪
速度Vwrl 、Vwrr の時間微分値として車輪加速度Vwd
rl、Vwdrrが演算されると共に、Cwfを車輪加速度より
前後力への変換係数として下記の数4に従って左右後輪
の回転慣性力についての補正値Fxirl、Fxirrが演算さ
れる。In step 23, the wheel acceleration Vwd is calculated as a time differential value of the left and right rear wheel speeds Vwrl, Vwrr.
rl and Vwdrr are calculated, and correction values Fxirl and Fxirr for the rotational inertia force of the left and right rear wheels are calculated according to the following Equation 4 using Cwf as a conversion coefficient from the wheel acceleration to the longitudinal force.
【数4】Fxirl=Cwf・Vwdrl Fxirr=Cwf・Vwdrr## EQU4 ## Fxirl = Cwf.Vwdrl Fxirr = Cwf.Vwdrr
【0036】ステップ24に於いては、下記の数5に従
って左右後輪の前後力差ΔFxrが演算され、ステップ2
5に於いては下記の数6に従って前後加速度Gx に基づ
く左右後輪の前後力Fxgrl、Fxgrrが演算される。In step 24, the longitudinal force difference ΔFxr between the left and right rear wheels is calculated according to the following equation (5).
In step 5, the longitudinal forces Fxgrl and Fxgrr of the left and right rear wheels based on the longitudinal acceleration Gx are calculated according to the following equation (6).
【0037】[0037]
【数5】 ΔFxr=(Fxbrl+Fxirl)−(Fxbrr+Fxirr)ΔFxr = (Fxbrl + Fxirl) − (Fxbrr + Fxirr)
【数6】Fxgrl=(Fxall−ΔFxr)/2 Fxgrr=(Fxall+ΔFxr)/2Fxgrl = (Fxall−ΔFxr) / 2 Fxgrr = (Fxall + ΔFxr) / 2
【0038】図4に示された左右後輪の前後力Fxtrl、
Fxtrr演算ルーチンのステップ31に於いては、エンジ
ン10の回転数Ne 及びトルクコンバータ12の出力回
転数Nout に基づき下記の数7に従ってトルクコンバー
タのスリップ比Rslが演算される。The longitudinal force Fxtrl of the left and right rear wheels shown in FIG.
In step 31 of the Fxtrr calculation routine, the slip ratio Rsl of the torque converter is calculated according to the following equation 7 based on the rotation speed Ne of the engine 10 and the output rotation speed Nout of the torque converter 12.
【数7】Rsl=Ne /Nout (Ne ≧Nout の場合) Rsl=Nout /Ne (Ne <Nout の場合)Rsl = Ne / Nout (when Ne ≧ Nout) Rsl = Nout / Ne (when Ne <Nout)
【0039】ステップ32に於いては、スリップ比Rsl
よりトルクコンバータ12の容量係数Cp を求めるため
の図には示されていないマップよりトルクコンバータの
容量係数Cp が演算され、ステップ33に於いては、下
記の数8に従ってトルクコンバータの入力トルクTinが
演算される。In step 32, the slip ratio Rsl
The capacity coefficient Cp of the torque converter is calculated from a map (not shown) for obtaining the capacity coefficient Cp of the torque converter 12, and in step 33, the input torque Tin of the torque converter is calculated according to the following equation (8). Is calculated.
【数8】Tin=Cp ・Ne 2 [Equation 8] Tin = Cp · Ne 2
【0040】ステップ34に於いては、スリップ比Rsl
よりトルクコンバータ12のトルク比Rtqを求めるため
の図には示されていないマップよりトルクコンバータの
トルク比Rtqが演算され、ステップ35に於いては下記
の数9に従ってトルクコンバータの出力トルクTout が
演算される。In step 34, the slip ratio Rsl
The torque ratio Rtq of the torque converter is calculated from a map (not shown) for obtaining the torque ratio Rtq of the torque converter 12, and in step 35, the output torque Tout of the torque converter is calculated according to the following equation (9). Is done.
【数9】Tout =Tin・Rtq## EQU9 ## Tout = Tin.Rtq
【0041】ステップ36に於いては、図3に示された
フローチャートのステップ22の場合と同様、上記数3
に従って左右後輪の制動力についての補正値Fxbrl、F
xbrrが演算され、ステップ37に於いては、図3に示さ
れたフローチャートのステップ23の場合と同様、上記
数4に従って左右後輪の回転慣性力についての補正値F
xirl、Fxirrが演算され、ステップ38に於いては下記
の数10に従ってトルクコンバータの出力トルクTout
に基づく左右後輪の前後力Fxtrl、Fxtrrが演算され
る。In step 36, as in step 22 in the flowchart shown in FIG.
Correction values Fxbrl, F for the braking force of the left and right rear wheels according to
xbrr is calculated, and in step 37, similarly to step 23 of the flowchart shown in FIG. 3, the correction value F for the rotational inertia of the left and right rear wheels is calculated according to the above equation (4).
xirl and Fxirr are calculated, and in step 38, the output torque Tout of the torque converter is calculated according to the following equation (10).
, Front-rear forces Fxtrl and Fxtrr of the left and right rear wheels are calculated.
【数10】Fxtrl=Tout /2−Fxbrl+Fxirl Fxtrr=Tout /2−Fxbrr+FxirrFxtrl = Tout / 2−Fxbrl + Fxirl Fxtrr = Tout / 2−Fxbrr + Fxirr
【0042】図5に示された四輪の接地荷重Fzj演算ル
ーチンのステップ41に於いては、Hを車輌の重心高さ
とし、Lを車輌のホイールベースとし、Tr を車輌のト
レッドとして下記の数11に従って車輌の前後加速度G
x 及び横加速度Gy に起因する前後方向及び横方向の荷
重移動量ΔFx 、ΔFy が演算される。In step 41 of the four wheel ground contact load Fzj calculation routine shown in FIG. 5, H is the height of the center of gravity of the vehicle, L is the wheelbase of the vehicle, and Tr is the tread of the vehicle. 11 the longitudinal acceleration G of the vehicle
The load movement amounts ΔFx and ΔFy in the front-rear direction and the lateral direction due to x and the lateral acceleration Gy are calculated.
【数11】ΔFx =M・H・Gx /L ΔFy =M・H・Gy /TrΔFx = M · H · Gx / L ΔFy = M · H · Gy / Tr
【0043】ステップ42に於いては、Mf 及びMr を
それぞれ左右前輪及び左右後輪が担持する車輌の重量と
し、gを重力加速度とし、Kf を前輪のロール剛性配分
比(1未満の正の定数)として下記の数12に従って旋
回内側前輪、旋回外側前輪、旋回内側後輪、旋回外側後
輪の接地荷重Fzfi 、Fzfo 、Fzri 、Fzro が演算さ
れる。In step 42, Mf and Mr are the weights of the vehicles carried by the left and right front wheels and the left and right rear wheels, g is the gravitational acceleration, and Kf is the roll rigidity distribution ratio of the front wheels (a positive constant less than 1). ), Ground contact loads Fzfi, Fzfo, Fzri, and Fzro of the turning inside front wheel, turning outside front wheel, turning inside rear wheel, and turning outside rear wheel are calculated according to the following Expression 12.
【数12】 Fzfi =Mf ・g−ΔFx /2−ΔFy ・Kf Fzfo =Mf ・g−ΔFx /2+ΔFy ・Kf Fzri =Mr ・g+ΔFx /2−ΔFy ・(1−Kf ) Fzro =Mr ・g+ΔFx /2+ΔFy ・(1−Kf )## EQU12 ## Fzfi = Mf.g-.DELTA.Fx / 2-.DELTA.Fy.KfFzfo = Mf.g-.DELTA.Fx / 2 + .DELTA.Fy.KfFzri = Mr.g + .DELTA.Fx / 2-.DELTA.Fy. (1-Kf) Fzro = Mr.g + .DELTA.Fx / 2 + .DELTA.・ (1-Kf)
【0044】ステップ43に於いては、車輌の横加速度
Gy が正であるか否かの判別、即ち車輌が左旋回中であ
るか否かの判別が行われ、肯定判別が行われたときには
ステップ44に於いて下記の数13に従って四輪の接地
荷重Fzj(j=fl、fr、rl、rr)が設定され、否定判別
が行われたときにはステップ45に於いて下記の数14
に従って四輪の接地荷重Fzjが設定される。尚車輌の旋
回方向の判定は操舵角又はヨーレートγの符号判別によ
り行われてもよく、それらの組合せにより行われてもよ
い。In step 43, it is determined whether or not the lateral acceleration Gy of the vehicle is positive, that is, whether or not the vehicle is turning to the left. In step 44, the four-wheel contact load Fzj (j = fl, fr, rl, rr) is set according to the following equation (13), and if a negative determination is made, the following equation (14) is determined in step 45.
, The ground load Fzj of the four wheels is set. The turning direction of the vehicle may be determined based on the sign of the steering angle or the yaw rate γ, or may be determined based on a combination thereof.
【0045】[0045]
【数13】Fzfl =Fzfi Fzfr =Fzfo Fzrl =Fzri Fzrr =FzroFzfl = Fzfi Fzfr = Fzfo Fzrl = Fzri Fzrr = Fzro
【数14】Fzfl =Fzfo Fzfr =Fzfi Fzrl =Fzro Fzrr =FzriFzfl = Fzfo Fzfr = Fzfi Fzrl = Fzro Fzrr = Fzri
【0046】図6に示された四輪のコーナリングフォー
スFyj演算ルーチンのステップ51に於いては、車輌の
横加速度Gy と車速V及びヨーレートγの積V・γとの
偏差Gy −V・γとして横加速度の偏差、即ち車輌の横
滑り加速度Vydが演算され、横滑り加速度Vydが積分さ
れることにより車体の横滑り速度Vy が演算され、更に
車体の前後速度Vx (=車速V)に対する車体の横滑り
速度Vy の比Vy /Vx として車体のスリップ角βが演
算される。In step 51 of the four-wheel cornering force Fyj calculation routine shown in FIG. 6, the deviation Gy−V · γ between the lateral acceleration Gy of the vehicle and the product V · γ of the vehicle speed V and the yaw rate γ is calculated. The deviation of the lateral acceleration, that is, the side slip acceleration Vyd of the vehicle is calculated, and the side slip speed Vy is calculated by integrating the side slip acceleration Vyd. Further, the side slip speed Vy of the vehicle with respect to the longitudinal speed Vx (= vehicle speed V) of the vehicle is calculated. Is calculated as the ratio Vy / Vx of the vehicle body.
【0047】ステップ52に於いては、車体のスリップ
角βの微分値βd 及び車輌のヨーレートγの微分値γd
が演算されると共に、Lf を車輌の重心と前輪車軸との
間の車輌前後方向の距離とし、Lr を車輌の重心と後輪
車軸との間の車輌前後方向の距離とし、Iz を車輌のヨ
ー慣性モーメントとして下記の数15に従って左右前輪
及び左右後輪のそれぞれについて合計のコーナリングフ
ォースFyf、Fyrが演算される。In step 52, the differential value βd of the slip angle β of the vehicle body and the differential value γd of the yaw rate γ of the vehicle
Lf is the distance between the center of gravity of the vehicle and the front wheel axle in the longitudinal direction of the vehicle, Lr is the distance between the center of gravity of the vehicle and the rear axle in the longitudinal direction of the vehicle, and Iz is the yaw of the vehicle. The total cornering forces Fyf and Fyr are calculated for each of the left and right front wheels and the left and right rear wheels as the moment of inertia according to Equation 15 below.
【数15】Fyf={M・V・Lr ・(βd +γ)+Iz
・γd }/L Fyr={M・V・Lf ・(βd +γ)−Iz ・γd }/
LFyf = {MV Lr (βd + γ) + Iz
・ Γd} / L Fyr = {MV ・ Lf ・ (βd + γ) -Iz ・ γd} /
L
【0048】ステップ53於いては、下記の数16に従
って各輪のコーナリングフォースFyj(j=fl、fr、r
l、rr)が演算される。In step 53, the cornering forces Fyj (j = fl, fr, r
l, rr) are calculated.
【数16】Fyfl =Fyf・Fzfl /(Fzfl +Fzfr ) Fyfr =Fyf・Fzfr /(Fzfl +Fzfr ) Fyrl =Fyr・Fzrl /(Fzrl +Fzrr ) Fyrr =Fyr・Fzrr /(Fzrl +Fzrr )Fyfl = Fyf · Fzfl / (Fzfl + Fzfr) Fyfr = Fyf · Fzfr / (Fzfl + Fzfr) Fyrl = Fyr · Fzrl / (Fzrl + Fzrr) Fyrr = Fyr · Fzrr / (Frr)
【0049】次に図7に示されたフローチャートを参照
して左右後輪の摩擦円半径Rmrl 、Rmrr の演算につい
て説明する。尚図7に示されたフローチャートによる演
算は左後輪(j=rl)及び右後輪(j=rr)について個
別に実行される。Next, the calculation of the friction circle radii Rmrl and Rmrr of the left and right rear wheels will be described with reference to the flowchart shown in FIG. The calculation according to the flowchart shown in FIG. 7 is executed individually for the left rear wheel (j = rl) and the right rear wheel (j = rr).
【0050】図7のサブルーチンのステップ101に於
いては、平均前後力Fxj及びコーナリングフォースFyj
に基づき下記の数17に従ってタイヤの発生力Fxyj が
演算され、ステップ102に於いては車速Vに基づき図
8に示されたグラフに対応するマップより目標車輪速度
Vwtが演算される。In step 101 of the subroutine of FIG. 7, the average longitudinal force Fxj and the cornering force Fyj
, The tire force Fxyj is calculated according to the following equation (17), and in step 102, the target wheel speed Vwt is calculated from the map corresponding to the graph shown in FIG.
【数17】Fxyj =(Fxj2 +Fyj2 )1/2 ## EQU17 ## Fxyj = (Fxj 2 + Fyj 2 ) 1/2
【0051】ステップ103に於いては、Vw1を正の定
数として、実車輪速度Vwjが基準値Vwt+Vw1を越えて
いるか否かの判別、即ち当該後輪が加速スリップの状態
にあるか否かの判別が行われ、肯定判別が行われたとき
にはステップ104に於いてカウンタのカウント値Cs
が1インクリメントされ、否定判別が行われたときには
ステップ105に於いてカウンタのカウント値Cs が0
にリセットされる。In step 103, it is determined whether or not the actual wheel speed Vwj exceeds the reference value Vwt + Vw1, using Vw1 as a positive constant, that is, whether or not the rear wheel is in an acceleration slip state. Is performed, and when a positive determination is made, the count value Cs of the counter is determined in step 104.
Is incremented by 1 and a negative determination is made in step 105 that the count value Cs of the counter is 0.
Is reset to
【0052】ステップ106に於いては、カウンタのカ
ウント値Cs が基準値Cse(正の一定の整数)であるか
否かの判別、即ち加速スリップが所定の時間継続したか
否かの判別が行われ、肯定判別が行われたときにはステ
ップ108へ進み、否定判別が行われたときにはステッ
プ107へ進む。In step 106, it is determined whether or not the count value Cs of the counter is a reference value Cse (a positive constant integer), that is, whether or not the acceleration slip has continued for a predetermined time. When the determination is affirmative, the process proceeds to step 108, and when the determination is negative, the process proceeds to step 107.
【0053】ステップ107に於いては、Vw2をVw1よ
りも大きい正の定数として、実車輪速度Vwjが基準値V
wt+Vw2を越えているか否かの判別、即ち当該後輪が過
大な加速スリップの状態にあるか否かの判別が行われ、
否定判別が行われたときには摩擦円半径が更新されるこ
となくステップ10へ戻り、肯定判別が行われたときに
はステップ108に於いてカウンタのカウント値Cs が
0にリセットされ、ステップ109に於いて摩擦円半径
Rmjがステップ101に於いて演算されたタイヤ発生力
Fxyj に更新された後ステップ10へ戻る。In step 107, the actual wheel speed Vwj is set to the reference value Vw2 by setting Vw2 as a positive constant larger than Vw1.
It is determined whether or not the value exceeds wt + Vw2, that is, whether or not the rear wheel is in an excessive acceleration slip state.
When a negative determination is made, the process returns to step 10 without updating the friction circle radius. When an affirmative determination is made, the count value Cs of the counter is reset to 0 in step 108, and the friction value is determined in step 109. After the circle radius Rmj is updated to the tire generating force Fxyj calculated in step 101, the process returns to step 10.
【0054】かくして図示の実施形態によれば、ステッ
プ20に於いて前後加速度Gx に基づく左右後輪の前後
力Fxgrl、Fxgrrが演算され、ステップ30に於いてト
ルクコンバータの出力トルクに基づく左右後輪の前後力
Fxtrl、Fxtrrが演算され、ステップ90に於いてこれ
らの重み平均値として左右後輪の前後力Fxrl 、Fxrr
が演算される。Thus, according to the illustrated embodiment, the longitudinal forces Fxgrl and Fxgrr of the left and right rear wheels based on the longitudinal acceleration Gx are calculated in step 20, and the left and right rear wheels based on the output torque of the torque converter are calculated in step 30. The longitudinal forces Fxtrl and Fxtrr of the right and left rear wheels are calculated in step 90 as an average of these weights.
Is calculated.
【0055】またステップ40に於いて四輪の接地荷重
Fzjが演算され、ステップ50に於いて各輪の接地荷重
に基づき四輪のコーナリングフォースFyjが演算され、
ステップ100に於いて左右後輪の前後力Fxrl 、Fxr
r 及びコーナリングフォースFyrl 、Fyrr の二乗和平
方根として左右後輪の摩擦円半径Rmrl 、Rmrr が演算
される。In step 40, the ground contact load Fzj of the four wheels is calculated, and in step 50, the cornering force Fyj of the four wheels is calculated based on the ground load of each wheel.
In step 100, the front-rear force Fxrl, Fxr of the left and right rear wheels
The friction circle radii Rmrl and Rmrr of the left and right rear wheels are calculated as the square root of the sum of squares of r and the cornering forces Fyrl and Fyrr.
【0056】従って図示の実施形態によれば、車輌全体
としての摩擦円半径ではなく、左右後輪の摩擦円半径R
mrl 及びRmrr を個別に正確に推定することができ、こ
れにより摩擦円半径との関連で左右後輪の駆動力を最適
に制御して左右後輪のトラクションを最適に制御するこ
とができる。Therefore, according to the illustrated embodiment, the friction radius R of the left and right rear wheels is not the radius of the friction circle of the entire vehicle.
mrl and Rmrr can be individually and accurately estimated, whereby the driving force of the left and right rear wheels can be optimally controlled in relation to the friction circle radius, and the traction of the left and right rear wheels can be optimally controlled.
【0057】特に図示の実施形態によれば、左右後輪の
前後力Fxrl 及びFxrr は前後加速度Gx に基づく前後
力Fxgrl、Fxgrrとトルクコンバータの出力トルクに基
づく前後力Fxtrl、Fxtrrとの重み平均値として演算さ
れ、ステップ60に於いて自動変速機の変速中である旨
の判別が行われるとステップ80に於いてトルクコンバ
ータの出力トルクに基づく前後力に対する重み係数Kx
が0に設定されるので、自動変速機の変速に起因して左
右後輪の駆動力が安定していない状況に於いてこれらに
基づき左右後輪の前後力が演算されることに起因して左
右後輪の摩擦円半径が不正確に演算されることを確実に
防止することができる。In particular, according to the illustrated embodiment, the longitudinal forces Fxrl and Fxrr of the left and right rear wheels are weighted average values of the longitudinal forces Fxgrl and Fxgrr based on the longitudinal acceleration Gx and the longitudinal forces Fxtrl and Fxtrr based on the output torque of the torque converter. When it is determined in step 60 that the automatic transmission is shifting, a weight coefficient Kx for the longitudinal force based on the output torque of the torque converter is determined in step 80.
Is set to 0, the front-rear force of the left and right rear wheels is calculated based on these in a situation where the driving force of the left and right rear wheels is not stable due to the shift of the automatic transmission. Incorrect calculation of the friction circle radii of the left and right rear wheels can be reliably prevented.
【0058】尚変速機がマニュアル式の変速機である車
輌の場合には、ステップ30、ステップ60〜90が省
略され、ステップ100に於いて左右後輪の摩擦円半径
Rmrl 、Rmrr は前後加速度Gx に基づく前後力Fxgr
l、FxgrrとコーナリングフォースFyrl 、Fyrr との
二乗和平方根として演算される。If the transmission is a vehicle of a manual type, step 30, steps 60 to 90 are omitted, and in step 100, the friction circle radii Rmrl and Rmrr of the right and left rear wheels are determined by the longitudinal acceleration Gx. Longitudinal force Fxgr based on
Calculated as the square root of the sum of squares of l, Fxgrr and cornering forces Fyrl, Fyrr.
【0059】以上に於ては本発明を特定の実施形態につ
いて詳細に説明したが、本発明は上述の実施形態に限定
されるものではなく、本発明の範囲内にて他の種々の実
施形態が可能であることは当業者にとって明らかであろ
う。In the above, the present invention has been described in detail with respect to a specific embodiment. However, the present invention is not limited to the above embodiment, and various other embodiments are included in the scope of the present invention. It will be clear to those skilled in the art that is possible.
【0060】例えば図示の実施形態に於いては、車輌は
自動変速機が搭載された後輪駆動車であり、左右後輪の
摩擦円半径が推定されるようになっているが、本発明は
前輪駆動車の左右前輪の摩擦円半径の推定に適用されて
もよい。For example, in the illustrated embodiment, the vehicle is a rear-wheel drive vehicle equipped with an automatic transmission, and the radius of the friction circle of the right and left rear wheels is estimated. It may be applied to the estimation of the friction circle radius of the left and right front wheels of the front wheel drive vehicle.
【0061】また図示の実施形態に於いては、駆動輪で
ある左右後輪の摩擦円半径が推定されるようになってい
るが、従動輪の操舵角が考慮された転がり抵抗やホイー
ルシリンダ内の圧力等に基づき従動輪の前後力が演算さ
れ、これらの前後力及びステップ50に於いて演算され
る従動輪のコーナリングフォースの二乗和平方根として
従動輪の摩擦円半径が推定されるよう構成されてもよ
い。In the illustrated embodiment, the friction circle radii of the left and right rear wheels, which are the driving wheels, are estimated. However, the rolling resistance and the wheel cylinder in consideration of the steering angle of the driven wheels are taken into consideration. The frictional radius of the driven wheel is estimated as the square root of the sum of squares of the front and rear forces of the driven wheel and the cornering force of the driven wheel calculated in step 50. You may.
【0062】[0062]
【発明の効果】以上の説明より明らかである如く、本発
明の請求項1の構成によれば、各輪毎に横力及び前後力
の二乗和平方根が演算され、各輪毎に車輪スリップが検
出されたときの二乗和平方根が当該車輪の摩擦円半径と
推定されるので、路面と各輪との間に作用する水平方向
の力に基づき各輪毎に個別に摩擦円半径を正確に推定す
ることができ、これにより駆動輪のトラクション制御や
車輪の制駆動力を制御することによる車輌の挙動制御を
過不足なく適切に行うことができる。As is apparent from the above description, according to the first aspect of the present invention, the root-sum-square of the lateral force and the longitudinal force is calculated for each wheel, and the wheel slip is calculated for each wheel. Since the square root of the sum of squares at the time of detection is estimated as the friction circle radius of the corresponding wheel, the friction circle radius is accurately estimated for each wheel individually based on the horizontal force acting between the road surface and each wheel. Accordingly, the vehicle behavior control by controlling the traction control of the drive wheels and the braking / driving force of the wheels can be appropriately performed without excess or deficiency.
【0063】また本発明の請求項2の構成によれば、左
右駆動輪の合計の駆動力が演算され、左右駆動輪の制駆
動力差及び左右駆動輪の車輪回転慣性力差に基づき左右
駆動輪の駆動力差が演算され、合計の駆動力及び駆動力
差に基づき各駆動輪の前後力が演算されるので、各駆動
輪の摩擦円半径の推定に必要な各駆動輪の前後力を正確
に推定することができる。According to the second aspect of the present invention, the total driving force of the left and right driving wheels is calculated, and the left and right driving wheels are driven based on the braking / driving force difference between the left and right driving wheels and the wheel rotation inertia difference between the left and right driving wheels. Since the driving force difference between the wheels is calculated, and the longitudinal force of each driving wheel is calculated based on the total driving force and the driving force difference, the longitudinal force of each driving wheel necessary for estimating the friction circle radius of each driving wheel is calculated. It can be accurately estimated.
【0064】更に本発明の請求項3又は4の構成によれ
ば、各駆動輪の前後力の推定に必要な左右駆動輪の合計
の駆動力を確実に推定することができる。Further, according to the third or fourth aspect of the present invention, it is possible to reliably estimate the total driving force of the left and right driving wheels required for estimating the longitudinal force of each driving wheel.
【図1】自動変速機が搭載され本発明に従って左右後輪
の摩擦円半径が推定される後輪駆動車を示す概略構成図
(A)及び制御系のブロック線図(B)である。FIG. 1 is a schematic configuration diagram (A) showing a rear wheel drive vehicle equipped with an automatic transmission and in which the friction circle radii of left and right rear wheels are estimated according to the present invention, and a block diagram (B) of a control system.
【図2】実施形態に於ける左右後輪の摩擦円半径推定の
メインルーチンを示すフローチャートである。FIG. 2 is a flowchart illustrating a main routine of estimating a friction circle radius of right and left rear wheels in the embodiment.
【図3】実施形態に於ける前後加速度Gx に基づく左右
後輪の前後力Fxgrl、Fxgrr演算のサブルーチンを示す
フローチャートである。FIG. 3 is a flowchart showing a subroutine for calculating the front and rear forces Fxgrl and Fxgrr of the left and right rear wheels based on the front and rear acceleration Gx in the embodiment.
【図4】実施形態に於けるトルクコンバータの出力トル
ク基づく左右後輪の前後力Fxtrl、Fxtrr演算のサブル
ーチンを示すフローチャートである。FIG. 4 is a flowchart showing a subroutine for calculating the front and rear forces Fxtrl and Fxtrr of the left and right rear wheels based on the output torque of the torque converter in the embodiment.
【図5】実施形態に於ける四輪の接地荷重Fzj演算のサ
ブルーチンを示すフローチャートである。FIG. 5 is a flowchart illustrating a subroutine for calculating a four-wheel ground contact load Fzj in the embodiment.
【図6】実施形態に於ける四輪のコーナリングフォース
Fyj演算のサブルーチンを示すフローチャートである。FIG. 6 is a flowchart illustrating a subroutine of a four-wheel cornering force Fyj calculation in the embodiment.
【図7】実施形態に於ける左右後輪の摩擦円半径Rmrl
、Rmrr 演算のサブルーチンを示すフローチャートで
ある。FIG. 7 shows a friction circle radius Rmrl of the left and right rear wheels in the embodiment.
, Rmrr is a flowchart showing a subroutine of calculation.
【図8】車速Vと目標車輪速度Vwtとの間の関係を示す
グラフである。FIG. 8 is a graph showing a relationship between a vehicle speed V and a target wheel speed Vwt.
【符号の説明】 10…エンジン 12…トルクコンバータ 16…自動変速機 20…ディファレンシャル 26…制動装置 28…油圧回路 30FL〜30RR…ホイールシリンダ 36…車輌運動制御コンピュータ 38…前後加速度センサ 40…横加速度センサ 42…車速センサ 44…ヨーレートセンサ 46RL、46RR…車輪速度センサ[Description of Signs] 10 ... Engine 12 ... Torque Converter 16 ... Automatic Transmission 20 ... Differential 26 ... Brake Device 28 ... Hydraulic Circuit 30FL-30RR ... Wheel Cylinder 36 ... Vehicle Motion Control Computer 38 ... Longitudinal Acceleration Sensor 40 ... Lateral Acceleration Sensor 42: Vehicle speed sensor 44: Yaw rate sensor 46RL, 46RR: Wheel speed sensor
Claims (4)
各輪の横力を推定する工程と、各輪の前後力を推定する
工程と、各輪毎に前記横力及び前記前後力の二乗和平方
根を演算する工程と、各輪毎に車輪スリップを検出する
工程と、各輪毎に車輪スリップが検出されたときの前記
二乗和平方根を当該車輪の摩擦円半径と推定する工程と
を有することを特徴とする方法。1. A method for estimating a friction circle radius of a wheel,
Estimating the lateral force of each wheel, estimating the longitudinal force of each wheel, calculating the root sum square of the lateral force and the longitudinal force for each wheel, and calculating the wheel slip for each wheel. Detecting, for each wheel, estimating the root-sum-square when wheel slip is detected for each wheel as the radius of the friction circle of the wheel.
定する工程は左右駆動輪の合計の駆動力を演算する工程
と、左右駆動輪の制駆動力差及び左右駆動輪の車輪回転
慣性力差に基づき左右駆動輪の駆動力差を演算する工程
と、前記合計の駆動力及び前記駆動力差に基づき各駆動
輪の前後力を演算する工程とを含むことを特徴とする請
求項1に記載の方法。2. The method according to claim 1, wherein the step of estimating the longitudinal force includes calculating a total driving force of the left and right driving wheels, and calculating a difference in braking / driving force of the left and right driving wheels and a wheel rotation of the left and right driving wheels. The method according to claim 1, further comprising: calculating a driving force difference between left and right driving wheels based on an inertial force difference; and calculating a longitudinal force of each driving wheel based on the total driving force and the driving force difference. 2. The method according to 1.
は前輪駆動車の左右前輪であり、前記左右駆動輪の合計
の駆動力は車輌の前後加速度と車輌の重量との積として
演算されることを特徴とする請求項2に記載の方法。3. The left and right driving wheels are left and right rear wheels of a rear wheel driving vehicle or left and right front wheels of a front wheel driving vehicle, and the total driving force of the left and right driving wheels is a product of a longitudinal acceleration of the vehicle and a weight of the vehicle. 3. The method according to claim 2, wherein the operation is performed.
は前輪駆動車の左右前輪であり、前記左右駆動輪の合計
の駆動力はトルクコンバータの出力トルクに基づき演算
されることを特徴とする請求項2に記載の方法。4. The vehicle according to claim 1, wherein the left and right drive wheels are left and right rear wheels of a rear wheel drive vehicle or left and right front wheels of a front wheel drive vehicle, and a total driving force of the left and right drive wheels is calculated based on an output torque of a torque converter. 3. The method according to claim 2, wherein the method comprises:
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JP27644897A JP3948076B2 (en) | 1997-09-24 | 1997-09-24 | Estimation method of friction circle radius of wheel |
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JP27644897A JP3948076B2 (en) | 1997-09-24 | 1997-09-24 | Estimation method of friction circle radius of wheel |
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Family
ID=17569581
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Cited By (4)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JP2008232080A (en) * | 2007-03-22 | 2008-10-02 | Fuji Heavy Ind Ltd | Drive force control device for vehicle |
JP2009241721A (en) * | 2008-03-31 | 2009-10-22 | Advics Co Ltd | Wheel lateral force estimating device of vehicle |
JP2020032961A (en) * | 2018-08-31 | 2020-03-05 | 株式会社アドヴィックス | Vehicle control device |
WO2023210535A1 (en) * | 2022-04-28 | 2023-11-02 | 三菱自動車工業株式会社 | Control device for vehicle |
-
1997
- 1997-09-24 JP JP27644897A patent/JP3948076B2/en not_active Expired - Lifetime
Cited By (5)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JP2008232080A (en) * | 2007-03-22 | 2008-10-02 | Fuji Heavy Ind Ltd | Drive force control device for vehicle |
JP2009241721A (en) * | 2008-03-31 | 2009-10-22 | Advics Co Ltd | Wheel lateral force estimating device of vehicle |
JP2020032961A (en) * | 2018-08-31 | 2020-03-05 | 株式会社アドヴィックス | Vehicle control device |
WO2020045566A1 (en) * | 2018-08-31 | 2020-03-05 | 株式会社アドヴィックス | Vehicle control device |
WO2023210535A1 (en) * | 2022-04-28 | 2023-11-02 | 三菱自動車工業株式会社 | Control device for vehicle |
Also Published As
Publication number | Publication date |
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JP3948076B2 (en) | 2007-07-25 |
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