JPH0640051B2 - Road condition determination device - Google Patents
Road condition determination deviceInfo
- Publication number
- JPH0640051B2 JPH0640051B2 JP61100140A JP10014086A JPH0640051B2 JP H0640051 B2 JPH0640051 B2 JP H0640051B2 JP 61100140 A JP61100140 A JP 61100140A JP 10014086 A JP10014086 A JP 10014086A JP H0640051 B2 JPH0640051 B2 JP H0640051B2
- Authority
- JP
- Japan
- Prior art keywords
- road surface
- driving force
- ratio
- steering
- traveling
- 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.)
- Expired - Lifetime
Links
Landscapes
- Steering-Linkage Mechanisms And Four-Wheel Steering (AREA)
Description
【発明の詳細な説明】 (産業上の利用分野) 本発明は、走行路面状態判別装置、特に車両走行中の路
面の摩擦係数の高低を判別する装置に関するものであ
る。BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a traveling road surface state determination device, and more particularly to a device for determining the level of friction coefficient of a road surface while a vehicle is traveling.
(従来の技術) 従来より、前輪の転舵に応じて後輪をも転舵するように
した車両の4輪転舵装置として、例えば特開昭55-91457
号公報に開示されるように、前輪を転舵する前輪転舵機
構と、後輪を転舵する後輪転舵機構とを備え、前輪の転
舵角および車速に応じて後輪の転舵角を変化させ、低速
時では前輪と後輪とを逆位相に、高速時では同位相にす
ることにより、車両の横すべりを防止して走行安定性を
向上させるとともに、低速時での小廻り性の向上を図り
得るようにしたものが知られている。(Prior Art) Conventionally, as a four-wheel steering device for a vehicle in which the rear wheels are also steered in accordance with the steering of the front wheels, for example, JP-A-55-91457.
As disclosed in the publication, a front wheel steering mechanism that steers the front wheels and a rear wheel steering mechanism that steers the rear wheels are provided. The steering angle of the rear wheels depends on the steering angle of the front wheels and the vehicle speed. The front and rear wheels have opposite phases at low speeds and the same phase at high speeds to prevent side slippage of the vehicle and improve running stability. It is known that it can be improved.
しかるに、雪道や凍結した道路などの低μ路走行時の如
くタイヤのグリップ力が低い状態では、通常走行時と同
様に後輪が転舵されると、前輪と後輪とが逆位相となる
低速時においては車両が横すべりを生じ易くなり、走行
安定性が損われるという問題がある。However, when the rear wheels are steered in the same way as during normal driving when the tire grip is low, such as when driving on low μ roads such as snowy roads and frozen roads, the front and rear wheels are out of phase. At such low speeds, the vehicle is likely to cause side skid, which causes a problem of impairing running stability.
このような問題に対して、車両走行中の路面の摩擦係数
の状況に応じて前輪に対する後輪の転舵比を適宜変更す
ることにより、通常走行時は勿論のこと、低μ路走行時
においても車輪の横すべりを最小限に押え、走行安定性
の向上を図ることが可能である。For such a problem, by appropriately changing the steering ratio of the rear wheels to the front wheels in accordance with the condition of the friction coefficient of the road surface while the vehicle is traveling, not only during normal traveling but also during traveling on a low μ road. It is also possible to suppress the side slip of the wheels to the minimum and improve the running stability.
(発明が解決しようとする問題点) 上記のような方法により車輪の横すべり防止を図るため
には、路面の摩擦係数を随時的確に判定できるようにす
ることが重要な前提条件となる。(Problems to be Solved by the Invention) In order to prevent the wheels from slipping by the above-described method, it is an important prerequisite that the friction coefficient of the road surface can be accurately determined at any time.
本発明は、このような事情に鑑みなされたものであっ
て、車両走行中の路面の摩擦係数の高低を判別すること
のできる走行路面状態判別装置を提供しようとするもの
である。The present invention has been made in view of such circumstances, and an object of the present invention is to provide a traveling road surface state determination device capable of discriminating whether the friction coefficient of a road surface during traveling of a vehicle is high or low.
(問題点を解決するための手段) 本発明による走行路面状態判別装置は、車両走行中のス
リップ率および駆動力係数を検出する一方、実験等によ
り、スリップ率と駆動力係数との関係を、路面の摩擦係
数をパラメータとする少なくとも1つの駆動力係数特性
として予め、記憶しておき、前記検出された駆動力係数
の値と、前記記憶されている駆動力係数特性における、
前記検出されたスリップ率に対応する駆動力係数の値と
を比較することにより、路面の摩擦係数の高低を判別す
るようにしたものである。すなわち車両走行中の路面の
状態を判別する走行路面状態判別装置であって、路面に
対する駆動輪のスリップ率を検出するスリップ率検出手
段と、車両の駆動装置の駆動力と前記駆動輪が受ける車
輪荷重の比を検出する駆動力係数検出手段と、予め実験
等により得られる特性であって、路面に対する駆動輪の
スリップ率と、車両の駆動装置の駆動力と駆動輪が受け
る車軸荷重の比との関係を、路面の摩擦係数をパラメー
タとして示す少なくとも1つの駆動力係数特性が記憶さ
れている記憶手段と、前記駆動力係数検出手段の検出信
号から得られた駆動力係数の値を、前記記憶手段に記憶
されている駆動力係数特性における、前記スリップ率検
出手段の検出信号から得られたスリップ率の値に対応す
る駆動力係数の値と比較して、車両走行中の路面の摩擦
係数の高低を判別する判別手段とを備えていることを特
徴とするものである。(Means for Solving Problems) The traveling road surface state determination device according to the present invention detects the slip ratio and the driving force coefficient while the vehicle is traveling, and on the other hand, performs the experiment to determine the relationship between the slip ratio and the driving force coefficient. Preliminarily stored as at least one driving force coefficient characteristic having a road surface friction coefficient as a parameter, and the value of the detected driving force coefficient and the stored driving force coefficient characteristic,
By comparing the value of the driving force coefficient corresponding to the detected slip ratio, it is possible to determine whether the friction coefficient of the road surface is high or low. That is, a traveling road surface state determination device for determining the state of a road surface while the vehicle is traveling, a slip ratio detection means for detecting a slip ratio of a drive wheel with respect to the road surface, a driving force of a drive device of a vehicle and a wheel received by the drive wheel. A driving force coefficient detecting means for detecting a load ratio, a characteristic obtained in advance by an experiment or the like, which is a slip ratio of a driving wheel with respect to a road surface, and a ratio of a driving force of a driving device of a vehicle and an axle load received by the driving wheel. The storage means stores at least one driving force coefficient characteristic indicating the friction coefficient of the road surface as a parameter, and the value of the driving force coefficient obtained from the detection signal of the driving force coefficient detecting means. In the driving force coefficient characteristic stored in the means, the value of the driving force coefficient corresponding to the value of the slip ratio obtained from the detection signal of the slip ratio detecting means is compared with And it is characterized in that it comprises a determining means for determining the height of the friction coefficient of the surface.
上記「駆動輪が受ける車軸荷重」とは、駆動時における
車両荷重移動量をも考慮に入れた駆動輪1輪当たりに作
用する垂直荷重を意味するものである。The above-mentioned "axle load received by the drive wheels" means a vertical load that acts on each drive wheel in consideration of the vehicle load movement amount during driving.
また上記「車両の駆動装置の駆動力と前記駆動輪が受け
る車軸荷重の比」で表わされる駆動力係数は、各駆動輪
すべてについて駆動力係数の値を求めてこれらの値を平
均することにより得るようにしてもよいし、特定の1つ
の駆動輪について駆動力係数を得るようにしてもよい。Further, the driving force coefficient represented by the "ratio between the driving force of the vehicle drive device and the axle load received by the driving wheels" is obtained by calculating the values of the driving force coefficients for all the driving wheels and averaging these values. The driving force coefficient may be obtained for one specific driving wheel.
(実施例) 以下、本発明の実施例を図面に基づいて説明する。(Example) Hereinafter, the Example of this invention is described based on drawing.
第1図は本発明の第1実施例に係る走行路面状態判別装
置が設けられた車両の4輪操舵装置の全体構成を示し、
1は左右の前輪2L,2Rを転舵する前輪転舵機構であ
って、該前輪転舵機構1は、ステアリングハンドル3
と、該ステアリングハンドル3の回転運動を直線運動に
変換するラック&ピニオン機構4と、該ラック&ピニオ
ン機構4の作動を前輪2L,2Rに伝達して、これらを
左右に転舵させる左右のタイロッド5,5およびナック
アーム6,6とからなる。FIG. 1 shows the overall configuration of a four-wheel steering system for a vehicle provided with a traveling road surface condition determining apparatus according to a first embodiment of the present invention.
Reference numeral 1 denotes a front wheel steering mechanism that steers left and right front wheels 2L and 2R. The front wheel steering mechanism 1 includes a steering handle 3
And a rack and pinion mechanism 4 that converts the rotational movement of the steering handle 3 into a linear movement, and the left and right tie rods that transmit the operation of the rack and pinion mechanism 4 to the front wheels 2L and 2R and steer them left and right. 5, 5 and nuck arms 6, 6.
7は左右の後輪8L,8Rを転舵する後輪転舵機構であ
って、該後輪転舵機構7は、両端が左右の後輪8L,8
Rにタイロッド9,9およびナックルアーム10,10を介
して連結された車幅方向に延びる後輪操作ロッド11を備
えている。該後輪操作ロッド11にはラック12が形成さ
れ、該ラック12に噛合するピニオン13がパルスモータ14
により一対の傘歯車15,16およびピニオン軸17を介して
回転されることにより、上記パルスモータ14の回転方向
および回転量に対応して後輪8L,8Rが左右に転舵さ
れるように構成されている。Reference numeral 7 denotes a rear wheel steering mechanism that steers the left and right rear wheels 8L and 8R. The rear wheel steering mechanism 7 has left and right rear wheels 8L and 8R at both ends.
The rear wheel operating rod 11 extending in the vehicle width direction is connected to the R via tie rods 9, 9 and knuckle arms 10, 10. A rack 12 is formed on the rear wheel operation rod 11, and a pinion 13 meshing with the rack 12 is provided with a pulse motor 14
Is rotated via a pair of bevel gears 15 and 16 and a pinion shaft 17, so that the rear wheels 8L and 8R are steered left and right in accordance with the rotation direction and rotation amount of the pulse motor 14. Has been done.
また、上記後輪操作ロッド11には、該ロッド11を操作ロ
ッドとするパワーシリンダ18が接続されている。該パワ
ーシリンダ18は、後輪操作ロッド11に固着したピストン
18a により車幅方向に仕切られた左転用油圧室18b およ
び右転用油圧室18c を有しているとともに、該各油圧室
18b ,18c はそれぞれ油圧通路19a ,19b を介して、パ
ワーシリンダ18への油供給方向および油圧を制御するコ
ントロールバルブ20に連通し、該コントロールバルブ20
には油供給通路21および油戻し路22を介して油圧ポンプ
23が接続されており、該油圧ポンプ23はモータ24によっ
て回転駆動される。上記コントロールバルブ20は、ピニ
オン軸17の回転方向を検出して後輪8L,8Rの左方向
転舵(図中反時計方向への転舵)時には油供給通路21を
左転用油圧室18b に連通しかつ右転用油圧室18c を油戻
し路22に連通する一方、後輪8L,8Rの右方向転舵
(図中時計方向への転舵)時には上記とは逆の連通状態
とし、同時に油圧ポンプ23からの油圧をピニオン軸17の
回転力に応じた圧力に減圧するものであり、パルスモー
タ14により傘歯車15,16、ピニオン軸17,ピニオン13お
よびラック12を介して後輪操作ロッド11が軸方向(車幅
方向)に移動されるときには、パワーシリンダ18への圧
油供給により上記後輪操作ロッド11の移動を助勢するよ
うにしている。A power cylinder 18 having the rod 11 as an operating rod is connected to the rear wheel operating rod 11. The power cylinder 18 is a piston fixed to the rear wheel operation rod 11.
It has a left-turning hydraulic chamber 18b and a right-turning hydraulic chamber 18c that are partitioned in the vehicle width direction by 18a.
18b and 18c communicate with a control valve 20 for controlling the oil supply direction to the power cylinder 18 and the hydraulic pressure via hydraulic passages 19a and 19b, respectively.
To the hydraulic pump via an oil supply passage 21 and an oil return passage 22.
23 is connected, and the hydraulic pump 23 is rotationally driven by a motor 24. The control valve 20 detects the rotation direction of the pinion shaft 17 and communicates the oil supply passage 21 with the counterclockwise hydraulic chamber 18b when the rear wheels 8L, 8R are steered to the left (steering counterclockwise in the figure). While the right-turning hydraulic chamber 18c is communicated with the oil return path 22, when the rear wheels 8L, 8R are steered to the right (steering in the clockwise direction in the figure), the communication state opposite to the above is established, and at the same time, the hydraulic pump The hydraulic pressure from 23 is reduced to a pressure corresponding to the rotational force of the pinion shaft 17, and the pulse motor 14 causes the rear wheel operating rod 11 to move through the bevel gears 15, 16, the pinion shaft 17, the pinion 13 and the rack 12. When it is moved in the axial direction (vehicle width direction), pressure oil is supplied to the power cylinder 18 to assist the movement of the rear wheel operation rod 11.
そして、上記パルスモータ14および油圧ポンプ23の駆動
用モータ24は、後輪転舵機構7の制御部たるコントロー
ラ25から出力される制御信号によって作動制御される。
上記コントローラ25には、前輪転舵機構1におけるステ
アリングハンドル3の操舵量等から前輪転舵角を検出す
る舵角センサ26からの舵角信号と、車速を検出する車速
センサ27からの車速信号と、車両走行中の路面の摩擦係
数の高低を判別する走行路面状態判別装置28からの路面
摩擦係数判別信号とがそれぞれ入力されているととも
に、バッテリ電源29が接続されている。The operation of the pulse motor 14 and the drive motor 24 of the hydraulic pump 23 is controlled by a control signal output from the controller 25 that is the control unit of the rear wheel steering mechanism 7.
The controller 25 receives a steering angle signal from a steering angle sensor 26 that detects a front wheel steering angle from the steering amount of the steering wheel 3 in the front wheel steering mechanism 1 and a vehicle speed signal from a vehicle speed sensor 27 that detects a vehicle speed. A road surface friction coefficient determination signal from a traveling road surface state determination device 28 that determines whether the friction coefficient of the road surface during traveling of the vehicle is high or low is input, and a battery power source 29 is connected.
上記コントローラ25の内部には、第2図に示すように、
車速に対する前輪と後輪の転舵比特性を第3図に示す如
く2種類記憶する特性記憶部30と、舵角センサ26からの
舵角信号および車速センサ27からの車速信号を受け、上
記特性記憶部30に記憶された転舵比特性から、前輪転舵
角と車速とに対応する後輪の目標転舵角を演算する目標
転舵角演算部31と、該目標転舵角演算部31で演算された
目標転舵角に対応するパルス信号を出力するパルスジェ
ネレータ32と、該パルスジェネレータ32からのパルス信
号を受けてパルスモータ14および油圧ポンプ23の駆動用
モータ24を駆動する駆動パルス信号に変換するドライバ
33とを備え、これらによって前輪転舵角に対する後輪転
舵角の比(転舵比)を所定の転舵比特性に従って可変と
して後輪転舵角が目標転舵角となるようにパルスモータ
14および油圧ポンプ23の駆動用モータ24を制御する転舵
比可変手段34が構成されている。Inside the controller 25, as shown in FIG.
A characteristic storage unit 30 that stores two types of steering ratio characteristics of the front wheels and the rear wheels with respect to the vehicle speed as shown in FIG. 3, a steering angle signal from the steering angle sensor 26, and a vehicle speed signal from the vehicle speed sensor 27 are received. From the turning ratio characteristics stored in the storage unit 30, a target turning angle calculation unit 31 that calculates a target turning angle of the rear wheels corresponding to the front wheel turning angle and the vehicle speed, and the target turning angle calculation unit 31 A pulse generator 32 that outputs a pulse signal corresponding to the target turning angle calculated in step S1, and a drive pulse signal that receives the pulse signal from the pulse generator 32 and drives the pulse motor 14 and the drive motor 24 of the hydraulic pump 23. Driver to convert
And a pulse motor so that the ratio of the rear wheel steering angle to the front wheel steering angle (steering ratio) can be varied according to a predetermined steering ratio characteristic so that the rear wheel steering angle becomes a target steering angle.
A turning ratio varying means 34 for controlling the driving motor 24 of the hydraulic pump 23 and the hydraulic pump 23 is configured.
ここに、上記特性記憶部30に予め記憶されている転舵比
特性は、第3図に示すように、晴天時などの路面の摩擦
係数が高い状態の通常走行時用の転舵比特性Aと、雨天
時や未舗装路などの低μ路走行時用の転舵比特性Bの2
種類であって、この両転舵比特性A,Bは、基本的に
は、車速が低速から高速に上昇するに従って転舵比kが
負方向の逆位相(前後輪が逆方向に転舵される状態)で
大きな値から零に近づくように移行し、中速域にて転舵
比kが正方向の同位相(前後輪が同方向に転舵される状
態)に変わり、高速域では同位相で転舵比kが大きくな
るように設定されている。そして、上記両転舵比特性
A,Bのうち、低μ路走行時用の転舵比特性Bは、通常
走行時の転舵比特性Aに比べて低速から高速までの全車
速域に亘って同位相側にずれた傾向にあり、転舵比kが
負方向の逆位相の値となる低速域ではその転舵比kが零
に近づきあるいは正方向の同位相に変化し、転舵比kが
正方向の同位相の値となる中速域ないし高速域ではその
転舵比kがより大きな値に設定されている。Here, as shown in FIG. 3, the steering ratio characteristic stored in advance in the characteristic storage unit 30 is a steering ratio characteristic A for normal running in a state where the friction coefficient of the road surface is high such as in fine weather. And 2 of the steering ratio characteristic B for running on low μ roads such as in the rain or on unpaved roads.
Basically, these two steering ratio characteristics A and B are basically the same as the steering ratio k in the negative phase (the front and rear wheels are steered in the opposite direction) as the vehicle speed increases from a low speed to a high speed. In the high speed range, the steering ratio k changes to the same phase in the positive direction (the front and rear wheels are steered in the same direction). The turning ratio k is set to increase with the phase. Of the two steering ratio characteristics A and B, the steering ratio characteristic B for low μ road traveling is wider than the steering ratio characteristic A for normal traveling over the entire vehicle speed range from low speed to high speed. The steering ratio k tends to shift to the same phase side, and the steering ratio k approaches zero or changes to the same phase in the positive direction in the low speed range where the steering ratio k becomes the value of the opposite phase in the negative direction. The steering ratio k is set to a larger value in the medium speed range or the high speed range where k has the same phase value in the positive direction.
そして、上記コントローラ25の内部には、さらに、走行
路面状態判別装置28からの路面摩擦係数判別信号を受け
る特性選択部35が備えられている。該特性選択部35は、
上記走行路面状態判別装置28からの判別信号により、路
面が設定値以上の摩擦係数を有する高μ路であるとの判
別結果を得たときには、上記特性記憶部30から通常走行
時用の転舵比特性Aを選択する一方、路面が設定値未満
の摩擦係数を有する低μ路であるとの判別結果を得たと
きには低μ路走行時用の転舵比特性Bを選択するもので
あって、該特性選択部35で選択された特性記憶部30の転
舵比特性に従って上記目標転舵角演算部31における目標
転舵角の演算が行なわれるようになっている。Further, inside the controller 25, there is further provided a characteristic selection unit 35 which receives a road surface friction coefficient determination signal from the traveling road surface state determination device 28. The characteristic selection unit 35
When the determination signal from the traveling road surface state determination device 28 obtains a determination result that the road surface is a high μ road having a friction coefficient of a set value or more, the steering for normal traveling from the characteristic storage unit 30 is obtained. While selecting the ratio characteristic A, the steering ratio characteristic B for traveling on the low μ road is selected when the determination result that the road surface is the low μ road having the friction coefficient less than the set value is obtained. The target turning angle calculation unit 31 calculates the target turning angle according to the turning ratio characteristic of the characteristic storage unit 30 selected by the characteristic selecting unit 35.
第1図に示すように、走行路面状態判別装置28は、AB
Sコンピュータ37に接続されていて、該ABSコンピュ
ータ37には、駆動輪たる前輪2L,2Rおよび従動輪た
る後輪8L,8Rの回転速度が各車輪回転センサ38から
入力されるようになっている。そして、ABSコンピュ
ータ37に入力された前輪2L,2Rの回転速度が駆動輪
速信号として、および後輪8L,8Rの回転速度が車速
信号としてそれぞれ走行路面状態判別装置28に入力され
るようになっている。また、ABSコンピュータ37は、
車速センサ27およびABSモジュレータ39にも接続され
ていて、後輪8L,8Rの車輪回転センサ38からの入力
信号に基づいて車速センサ27に車速信号を出力し、AB
Sモジュレータ39に、各車輪2L,2R,8L,8Rの
制動装置に供給するブレーキ液圧の制御信号を出力する
ようになっている。As shown in FIG. 1, the traveling road surface state determination device 28 is
It is connected to the S computer 37, and the ABS computer 37 receives the rotation speeds of the front wheels 2L and 2R, which are driving wheels, and the rear wheels 8L and 8R, which are driven wheels, from the wheel rotation sensors 38. . Then, the rotational speeds of the front wheels 2L and 2R, which are input to the ABS computer 37, are input to the traveling road surface state determination device 28 as driving wheel speed signals, and the rotational speeds of the rear wheels 8L and 8R are input to the traveling road surface state determination device 28, respectively. ing. In addition, the ABS computer 37
It is also connected to the vehicle speed sensor 27 and the ABS modulator 39, and outputs a vehicle speed signal to the vehicle speed sensor 27 on the basis of an input signal from the wheel rotation sensor 38 of the rear wheels 8L and 8R.
A control signal of the brake fluid pressure supplied to the braking device of each wheel 2L, 2R, 8L, 8R is output to the S modulator 39.
上記走行路面状態判別装置28は、さらに、車軸荷重セン
サ40および制動力センサ41に接続されていて、車軸荷重
センサ40からは、駆動輪たる前輪2L,2Rのそれぞれ
が受ける車軸荷重を検出した検出信号が入力され、駆動
力センサ41からは、前輪2L,2Rのそれぞれに作用す
る駆動装置の駆動力を検出した検出信号が入力されるよ
うになっている。The traveling road surface state determination device 28 is further connected to an axle load sensor 40 and a braking force sensor 41, and detects from the axle load sensor 40 the axle load received by each of the front wheels 2L, 2R that are drive wheels. A signal is input, and from the driving force sensor 41, a detection signal for detecting the driving force of the drive device acting on each of the front wheels 2L, 2R is input.
上記車軸荷重は、駆動時における車両荷重移動量をも考
慮に入れた前輪2L,2Rの1輪当りに作用する垂直荷
重であって、例えば次のようにして得ることができる。
すなわち、サスペンションのコイルスプリングの変位量
と前記垂直荷重との間には比例関係があることから、コ
イルスプリングの表面にひずみセンサ(ストレインゲー
ジ)を取り付けることにより検出することができる。し
たがって車軸荷重をW、ひずみセンサの出力値をQとす
れば、W=rQ(r:定数) で表わすことができる。The axle load is a vertical load that acts on each of the front wheels 2L and 2R in consideration of the vehicle load movement amount during driving, and can be obtained as follows, for example.
That is, since there is a proportional relationship between the amount of displacement of the coil spring of the suspension and the vertical load, it can be detected by attaching a strain sensor (strain gauge) to the surface of the coil spring. Therefore, if the axle load is W and the output value of the strain sensor is Q, it can be expressed by W = rQ (r: constant).
一方、上記駆動力は、駆動時において駆動輪と路面との
間に働く接線力であって、次のようにして得ることがで
きる。すなわち、駆動力をDとすれば、 D=a+bTD a,b:定数 :車輪の回転速度 TD:駆動トルク で表わすことができる。ここに駆動トルクTDは駆動輪
のドライブシャフトのねじり量に対応したものとなるの
で、ドライブシャフトのねじり量を検出するセンサによ
り検出することが可能である。例えば、第4a図に示すよ
うに、ドライブシャフトの軸方向に所定間隔を置いて1
対のピックアップP1,P2を設け、第4b図に示すよう
に、これらピックアップP1,P2の出力パルスの時間
的変位からドライブシャフトのねじり量Rを求めれば、
駆動トルクTDは、 TD=lR(l:定数) で表わすことができる。したがって駆動力Dは、 D=α−βR で表わすことができる。On the other hand, the driving force is a tangential force acting between the driving wheel and the road surface during driving, and can be obtained as follows. That is, when the driving force is D, it can be expressed by D = a + bT D a, b: constant: wheel rotation speed T D : driving torque. Since the drive torque T D corresponds to the twist amount of the drive shaft of the drive wheel, it can be detected by a sensor that detects the twist amount of the drive shaft. For example, as shown in Fig. 4a, 1
If a pair of pickups P 1 and P 2 are provided and, as shown in FIG. 4b, the amount of twist R of the drive shaft is obtained from the time displacement of the output pulse of these pickups P 1 and P 2 ,
The driving torque T D can be represented by T D = lR (l: constant). Therefore, the driving force D can be represented by D = α−βR.
第5図は、走行路面状態判別装置28の構成を示すブロッ
ク図である。FIG. 5 is a block diagram showing the configuration of the traveling road surface state determination device 28.
走行路面状態判別装置28は、スリップ率検出部42、駆動
力係数検出部43、記憶部44および判別部45を備えてなる
ものであって、第6図に示すフローに従って車両走行中
の路面の摩擦係数の高低の判別をするようになってい
る。The traveling road surface state determination device 28 includes a slip ratio detection unit 42, a driving force coefficient detection unit 43, a storage unit 44, and a determination unit 45, and detects the road surface on which the vehicle is traveling according to the flow shown in FIG. It is designed to determine whether the friction coefficient is high or low.
すなわち、スリップ率検出部42において、ABSコンピ
ュータ37からの入力信号として得られる駆動輪速VDお
よび車速Voに基づき、(VD−VO)/VD× 100の
演算処理がなされ、スリップ率Sの値が検出される。That is, in the slip ratio detecting unit 42, the calculation processing of (V D −V O ) / V D × 100 is performed based on the drive wheel speed V D and the vehicle speed V o obtained as the input signal from the ABS computer 37, and the slip is detected. The value of the rate S is detected.
一方、駆動力係数検出部43において、車軸荷重センサ40
から入力される車軸荷重Wおよび駆動力センサ41から入
力される駆動力Dに基づき、D/Wの演算処置がなされ
駆動力係数μDの値が検出される。On the other hand, in the driving force coefficient detection unit 43, the axle load sensor 40
Based on the axle load W input from the driving force sensor and the driving force D input from the driving force sensor 41, D / W is calculated, and the value of the driving force coefficient μ D is detected.
こうして検出されたスリップ率Sおよび駆動力係数μD
の値は、判別部45に入力され、該判別部45において、記
憶部44に記憶されている路面状態判別マップとの照合が
なされ、これにより路面の摩擦係数の高低の判別がなさ
れるようになっている。The slip ratio S and the driving force coefficient μ D thus detected
The value of is input to the discriminating unit 45, and in the discriminating unit 45, the value is compared with the road surface state discrimination map stored in the storage unit 44, so that whether the friction coefficient of the road surface is high or low is determined. Has become.
路面状態判別マップは、第7図に示すように、路面に対
する駆動輪のスリップ率Sと駆動力係数μD(なわち駆
動装置の駆動力Dと駆動輪が受ける車軸荷重Wの比)と
の関係を示すグラフであって、路面の摩擦係数μをパラ
メータとする少なくとも1つの制動力係数特性曲線が示
されてなるものである。上記駆動力係数特性曲線は、実
験等により得ることができる特性曲線である。図には、
路面の摩擦係数μが0.6のドライコンクリート路面お
よびμが0.15の氷上においてそれぞれ実験により求
めた駆動力係数特性曲線EおよびFと、これら2つの特
性曲線E,Fから補間法を用いて算出された駆動力係数
特性曲線Gとが示されている。この特性曲線Gは、車両
走行中の路面が高μ路か低μ路かの判別を行う際の基準
となる路面の摩擦係数に対応する駆動力係数特性を示す
曲線である 第5および6図において、スリップ率検出部42および駆
動力係数検出部43から判別部45に入力されたスリップ率
Sおよび駆動力係数μDの値は、第7図に示すように、
記憶部44に記憶されている路面状態判別マップに座標点
X(S,μD)として表わされ、この点Xが、基準とな
る駆動力係数特性曲線Gに対して上にあるか下にあるか
によって、車両走行中の路面の摩擦係数の高低が判別さ
れることとなる。例えば、判別部45に、S=30%、μD
=0.4なる検出信号が入力されると、駆動力係数特性
曲線GにおけるS=30%に対応する駆動力係数の値0.
35と上記μD=0.4との比較がなされ、μD=0.
4>0.35として、点X(S=30,μD=0.4)は
特性曲線Gより上にあることが判別される。これによ
り、車両走行中の路面の摩擦係数が設定値より高いこ
と、すなわち高μ路であることが判明される。As shown in FIG. 7, the road surface state determination map includes a slip ratio S of the driving wheels with respect to the road surface and a driving force coefficient μ D (that is, a ratio of the driving force D of the driving device and the axle load W received by the driving wheels). It is a graph showing the relationship, and at least one braking force coefficient characteristic curve with the friction coefficient μ of the road surface as a parameter is shown. The driving force coefficient characteristic curve is a characteristic curve that can be obtained by experiments or the like. In the figure,
Driving force coefficient characteristic curves E and F obtained by experiments on a dry concrete road surface with a friction coefficient μ of 0.6 and on ice with a μ of 0.15, and an interpolation method is used from these two characteristic curves E and F. The driving force coefficient characteristic curve G calculated by the above is shown. This characteristic curve G is a curve showing the driving force coefficient characteristic corresponding to the friction coefficient of the road surface which serves as a reference when determining whether the road surface on which the vehicle is traveling is a high μ road or a low μ road. In FIG. 7, the values of the slip ratio S and the driving force coefficient μ D input from the slip ratio detecting unit 42 and the driving force coefficient detecting unit 43 to the discriminating unit 45 are as shown in FIG.
It is represented as a coordinate point X (S, μ D ) on the road surface state determination map stored in the storage unit 44, and this point X is above or below the reference driving force coefficient characteristic curve G. Whether or not the friction coefficient of the road surface during traveling of the vehicle is high or low is determined. For example, if the determination unit 45 has S = 30%, μ D
= 0.4, the value of the driving force coefficient corresponding to S = 30% in the driving force coefficient characteristic curve G is 0.
35 and the above μ D = 0.4, and μ D = 0.
As 4> 0.35, it is determined that the point X (S = 30, μ D = 0.4) is above the characteristic curve G. This reveals that the coefficient of friction of the road surface on which the vehicle is traveling is higher than the set value, that is, it is a high μ road.
第7図においては、記憶部44に記憶されている駆動力係
数特性曲線が、E,F,Gの3つで、基準となる特性曲
線はG1つとして示してなるが、基準となる特性曲線を
複数設定して高μ路、低μ路の2段階判別ではなく、よ
り多くの段階に分けて路面の摩擦係数の高低を相細かく
判別するようにしてもよい。この場合、基準となる特性
曲線をすべて補間法により求めるようにしてもよいが、
高低さまざまの摩擦係数を有する路面での走行実験等に
よる実測データから得た複数の特性曲線をそのまま用い
て基準となる特性曲線とするようにしてもよい。In FIG. 7, the driving force coefficient characteristic curves stored in the storage unit 44 are three, E, F, and G, and the reference characteristic curve is G1, but the reference characteristic curve is shown. It is also possible to set a plurality of values to determine the level of the friction coefficient of the road surface finely by dividing into more stages instead of the two-stage determination of the high μ road and the low μ road. In this case, it is possible to obtain all the reference characteristic curves by interpolation,
It is also possible to use a plurality of characteristic curves obtained from actual measurement data obtained by running experiments on a road surface having various high and low friction coefficients as they are and use them as reference characteristic curves.
このようにして判別部45にて車両走行中の路面の摩擦係
数μの高低が判別されると、該判別信号が4輪操舵用の
コントローラ25に入力され、転舵比特性の可変制御がな
されることとなる。In this way, when the discriminating unit 45 discriminates whether the friction coefficient μ of the road surface during traveling of the vehicle is high or low, the discriminating signal is inputted to the four-wheel steering controller 25, and the steering ratio characteristic is variably controlled. The Rukoto.
次に、上記第1実施例の作用・効果について説明する
に、路面の摩擦係数が設定値以上の通常走行時の場合に
は、後輪転舵機構7のコントローラ25においては、特性
選択部35で特性記憶部30に記憶された2種類の転舵比特
性A,Bの中から通常走行時用の転舵比特性Aが選択さ
れ、この選択された転舵比特性Aに基づいて転舵比可変
手段34の目標転舵角演算部31で目標転舵角が演算される
ことにより、前輪転舵角に対する後輪転舵角の転舵比が
上記通常走行時用の転舵比特性Aに従って可変制御さ
れ、その結果、後輪8L,8Rは、低車速時では前輪2
L,2Rと逆位相に転舵され、中・高車速時では前輪2
L,2Rと同位相に転舵される。Next, the operation and effect of the above-described first embodiment will be described. When the road surface friction coefficient is equal to or greater than the set value during normal running, the controller 25 of the rear wheel steering mechanism 7 uses the characteristic selection unit 35. The steering ratio characteristic A for normal traveling is selected from the two types of steering ratio characteristics A and B stored in the characteristic storage unit 30, and the steering ratio based on the selected steering ratio characteristic A. Since the target turning angle is calculated by the target turning angle calculation unit 31 of the variable means 34, the turning ratio of the rear wheel turning angle to the front wheel turning angle is changed according to the turning ratio characteristic A for the normal running. As a result, the rear wheels 8L and 8R are controlled so that at low vehicle speeds, the front wheels 2L and 8R
The front wheels 2 are steered in the opposite phase of L and 2R, and at medium and high vehicle speeds.
It is steered in the same phase as L and 2R.
一方、路面の摩擦係数が設定値未満になる雨天時や未舗
装路,雪路走行時の場合には、上記特性選択部35は、走
行路面状態判別装置28からの路面摩擦係数判別信号を受
けて上述の通常走行時用の転舵比特性Aに代って低μ路
走行時用の転舵比特性Bを特性記憶部30から選択し、こ
の選択された低μ路走行時用の転舵比特性Bに従って転
舵比が転舵比可変手段34によって可変制御される。On the other hand, when the road surface friction coefficient is less than the set value in rainy weather, unpaved roads, or snowy roads, the characteristic selection unit 35 receives the road surface friction coefficient determination signal from the traveling road surface state determination device 28. Then, instead of the steering ratio characteristic A for normal traveling described above, the steering ratio characteristic B for traveling on a low μ road is selected from the characteristic storage unit 30, and the selected steering characteristic for traveling on a low μ road is selected. The turning ratio is variably controlled by the turning ratio changing means 34 in accordance with the turning ratio characteristic B.
この場合、上記低μ路走行時用の転舵比特性Bは、通常
走行時用の転舵比特性Aに比べて同位相側にずれている
ので、後輪8L,8Rが通常走行時よりも前輪2L,2
Rと同位相方向に転舵されて車輪の横方向グリップ力が
増大し、その結果、低μ路走行時においても車輪(前輪
2L,2Rおよび後輪8L,8R)の横すべりが可及的
に防止されることになる。よって、走行安定性の向上を
図ることができる。In this case, since the steering ratio characteristic B for traveling on the low μ road is deviated to the same phase side as compared with the steering ratio characteristic A for traveling normally, the rear wheels 8L, 8R are more than those in traveling normally. Front wheels 2L, 2
The steering wheel is steered in the same phase direction as R to increase the lateral gripping force of the wheels, and as a result, the wheels (the front wheels 2L, 2R and the rear wheels 8L, 8R) can be laterally slid even when traveling on a low μ road. Will be prevented. Therefore, traveling stability can be improved.
第8図は上記第1実施例における後輪転舵機構7のコン
トローラ25の変形例を示したものである。このコントロ
ーラ25は、目標転舵角演算部31′とパルスジェネレータ
32′とドライバ33′とによって構成され、前輪転舵角に
対する後輪転舵角の転舵比を特性記憶部30′に記憶され
た所定の転舵比特性(第1実施例における特性記憶部30
に記憶された通常走行時用の転舵比特性Aに相当)に従
って可変制御する転舵比可変手段34′を備えているとと
もに、走行路面状態判別装置28からの路面摩擦係数判別
信号を受け、路面摩擦係数の低下に応じて上記転舵比可
変手段34′の目標転舵角演算部31′で演算された目標転
舵角に対して漸次正方向の補正転舵角を加算して、転舵
比を漸次同位相方向に大きく補正する補正手段としての
補正部36を備えてなるものである。すなわち、この変形
例においては、走行路面状態判別装置28における路面の
摩擦係数の高低の判別は、基準となる駆動力係数特性を
複数設定して、車両走行中に検出されたスリップ率およ
び駆動力係数の値をこれらの特性と照合することにより
なされることとなる。FIG. 8 shows a modified example of the controller 25 of the rear wheel steering mechanism 7 in the first embodiment. This controller 25 includes a target steering angle calculation unit 31 'and a pulse generator.
A predetermined steering ratio characteristic (a characteristic storage unit 30 in the first embodiment, which includes a steering ratio of a rear wheel steering angle to a front wheel steering angle and is stored in a characteristic storage unit 30 ', is constituted by a driver 32' and a driver 33 '.
The steering ratio varying means 34 'is variably controlled in accordance with the steering ratio characteristic A for normal traveling stored in (4), and receives the road surface friction coefficient discrimination signal from the traveling road surface state discrimination device 28. In accordance with the decrease in the road surface friction coefficient, the corrected steered angle in the positive direction is gradually added to the target steered angle calculated by the target steered angle calculation unit 31 'of the steered ratio varying means 34', and the steered ratio is changed. The correction unit 36 is provided as a correction unit that gradually and largely corrects the steering ratio in the same phase direction. That is, in this modified example, in the determination of the level of the friction coefficient of the road surface in the traveling road surface state determination device 28, a plurality of reference driving force coefficient characteristics are set, and the slip ratio and the driving force detected during vehicle traveling are set. It will be done by matching the values of the coefficients with these properties.
したがって、上記変形例の場合には、通常走行時用の転
舵比特性が路面の摩擦係数の低下に応じて同位相方向に
漸次大きく補正されるので、上記第1実施例の如く路面
摩擦係数が設定値未満となった時点で転舵比特性を通常
走行時用から低μ路走行時用のものに切換え選択する場
合に比べて転舵比の制御精度が細かくなり、走行安定性
の向上をより一層図ることができる。Therefore, in the case of the modified example, the steering ratio characteristic for normal traveling is gradually corrected in the same phase direction as the friction coefficient of the road surface decreases, so that the road surface friction coefficient as in the first embodiment is increased. When the value becomes less than the set value, the steering ratio control accuracy becomes finer and the running stability is improved compared to the case where the steering ratio characteristics are switched from those for normal driving to those for low μ road driving. Can be further improved.
また、第9図は上記第1実施例の変形例として前輪転舵
角θFの大きさに応じて後輪転舵角θRを演算して転舵
比を制御する場合の転舵比特性を示したものである。こ
の舵角による転舵比制御は、前輪転舵角θFが高車速時
では小さく、低車速時では大きくなるという実情に基づ
いて前輪転舵角θFに対する後輪転舵角θRの転舵比を
制御するものであり、その転舵比特性は、基本的には車
速による転舵比制御の場合と同様、低車速時では前輪と
後輪とを逆位相に、高車速時では同位相にするように設
定されている。Further, FIG. 9 shows a steering ratio characteristic when the steering ratio is controlled by calculating the rear-wheel steering angle θ R according to the magnitude of the front-wheel steering angle θ F as a modification of the first embodiment. It is shown. The steering ratio control by the steering angle, the front wheel turning angle theta F is smaller than at high vehicle speed, steering of the rear wheel steering angle theta R for the front wheel turning angle theta F based on the actual situation that becomes large at the time of low vehicle speed The steering ratio characteristic is basically the same as in the case of steering ratio control by vehicle speed, in which the front wheel and the rear wheel are in opposite phases at low vehicle speeds and at the same phase at high vehicle speeds. Is set to.
そして、上記舵角による転舵比制御の場合においても、
その転舵比特性としては、通常走行時用の転舵比特性C
と低μ路走行時用の転舵比特性Dの2種類がある。低μ
路走行時用の転舵比特性Dは、通常走行時用の転舵比特
性Cに比べて前輪転舵角θFの全範囲に亘って後輪転舵
角θRの正方向の同位相側にずれた傾向にあり、路面摩
擦係数が設定値未満の状態において、この転舵比特性D
に従って後輪が第1実施例の場合と同様に通常走行時よ
りも前輪と同位相方向に転舵される。尚、舵角による転
舵比制御の場合には、第1実施例の如き車速を検出する
車速センサ27は不要である。Then, even in the case of the steering ratio control by the steering angle,
As the steering ratio characteristic, the steering ratio characteristic C for normal traveling is used.
And a steering ratio characteristic D for traveling on a low μ road. Low μ
Compared with the steering ratio characteristic C for normal traveling, the steering ratio characteristic D for road traveling has a positive in-phase side of the rear wheel steering angle θ R over the entire range of the front wheel steering angle θ F. When the road surface friction coefficient is less than the set value, the steering ratio characteristic D
Accordingly, the rear wheels are steered in the same phase direction as the front wheels as compared with the case of normal traveling, as in the case of the first embodiment. In the case of the steering ratio control by the steering angle, the vehicle speed sensor 27 for detecting the vehicle speed as in the first embodiment is unnecessary.
さらに、第10図は本発明の第2実施例に係る車両の4輪
操舵装置の全体構成を示し、この4輪操舵装置における
後輪転舵機構7′は、第1実施例の4輪操舵装置におけ
る後輪転舵機構7の如くパルスモータ14の作動により後
輪8L,8Rを電気的に転舵する代わりに、前輪転舵機
構1の操舵力を利用して後輪8L,8Rを機械的に転舵
するようにしたものである。Furthermore, FIG. 10 shows the overall construction of a four-wheel steering system for a vehicle according to a second embodiment of the present invention. The rear wheel steering mechanism 7'in this four-wheel steering system is the four-wheel steering system of the first embodiment. Instead of electrically steering the rear wheels 8L, 8R by operating the pulse motor 14 as in the rear wheel steering mechanism 7 in FIG. 1, the steering force of the front wheel steering mechanism 1 is used to mechanically drive the rear wheels 8L, 8R. It was designed to be steered.
すなわち、上記後輪転舵機構7′は、ギヤ等からなる転
舵比変更装置46を備え、該転舵比変更装置46には車体前
後方向に延びる伝達ロッド47の後端が連結され、該伝達
ロッド47の全端部には、前輪転舵機構1のラック&ピニ
オン機構4のラック軸4aに形成されたラック48と噛合す
るピニオン49が設けられている。また、上記転舵比変更
装置46からは摺動部材50が延出され、該摺動部材50に形
成されたラック51に対しては、後輪操作ロッド11にラッ
ク12およびピニオン13を介して連結されたピニオン軸17
の前端部に設けたピニオン52が噛合している。しかし
て、前輪転舵機構1の操舵力がラック&ピニオン機構4
のラック軸4aから伝達ロッド47を介して転舵比変更装置
46に伝達され、該転舵比変更装置46においてコントロー
ラ25の制御に従って転舵比が変更された後に操舵力が摺
動部材50およびピニオン軸17を介して後輪操作ロッド11
に伝達されることにより、後輪8L,8Rが左右に転舵
されるように構成されている。尚、4輪操舵装置のその
他の構成は、第1実施例の4輪操舵装置と同じであり、
同一部材には同一部号を付してその説明は省略する。That is, the rear wheel turning mechanism 7'includes a turning ratio changing device 46 including gears, and the turning ratio changing device 46 is connected to a rear end of a transmission rod 47 extending in the vehicle front-rear direction. A pinion 49 that meshes with a rack 48 formed on the rack shaft 4a of the rack and pinion mechanism 4 of the front wheel steering mechanism 1 is provided at all ends of the rod 47. A sliding member 50 extends from the steering ratio changing device 46, and a rack 51 formed on the sliding member 50 is attached to the rear wheel operation rod 11 via the rack 12 and the pinion 13. Articulated pinion shaft 17
The pinion 52 provided at the front end of the is meshed. Then, the steering force of the front wheel steering mechanism 1 is equal to the rack and pinion mechanism 4
Steering ratio changing device from the rack shaft 4a of the vehicle through the transmission rod 47
The steering force is transmitted to the rear wheel operation rod 11 via the sliding member 50 and the pinion shaft 17 after the steering ratio is changed under the control of the controller 25 in the steering ratio changing device 46.
The rear wheels 8L and 8R are steered to the left and right by being transmitted to. The other configurations of the four-wheel steering system are the same as those of the four-wheel steering system of the first embodiment.
The same members are designated by the same reference numerals and the description thereof will be omitted.
そして、上記転舵比変更装置46を制御するコントローラ
25自体は、第1実施例の場合と同じであり、また、それ
により同様の作用・効果を奏することができるのは勿論
である。And a controller for controlling the turning ratio changing device 46.
Of course, 25 itself is the same as that of the first embodiment, and of course, the same action and effect can be obtained.
(発明の効果) 以上詳述したように、本発明による走行路面状態判別装
置は、スリップ率検出手段および駆動力係数検出手段に
より、車両走行中のスリップ率および駆動力係数を検出
する一方、記憶手段により、スリップ率と駆動力係数と
の関係を、路面の摩擦係数をパラメータとする少なくと
も1つの駆動力係数特性として予め記憶しておき、判別
手段により、前記検出された駆動力係数の値と、前記記
憶されている駆動力係数特性における、前記検出された
スリップ率に対応する駆動力係数の値とを比較して、路
面の摩擦係数の高低の判別を行うようになっているの
で、簡単かつ的確に路面状態の判別を行うことが可能と
なる。(Effects of the Invention) As described in detail above, the traveling road surface state determination device according to the present invention detects the slip ratio and the driving force coefficient during traveling of the vehicle by the slip ratio detecting means and the driving force coefficient detecting means, while storing them. The means stores in advance the relationship between the slip ratio and the driving force coefficient as at least one driving force coefficient characteristic using the friction coefficient of the road surface as a parameter, and the determining means determines the value of the detected driving force coefficient. , The stored driving force coefficient characteristic is compared with the value of the driving force coefficient corresponding to the detected slip ratio to determine whether the friction coefficient of the road surface is high or low. In addition, it is possible to accurately determine the road surface condition.
第1図は本発明による走行路面状態判別装置が設けられ
た車両の4輪操舵装置の一例を示す概要図、 第2図は4輪操舵装置のコントローラのブロック図、 第3図はコントローラが車速による転舵比制御を行う場
合における転舵比特性を示す図、 第4aおよび4b図は駆動トルク検出のための説明図、 第5図は走行路面状態判別装置の構成を示すブロック
図、 第6図は走行路面状態判別装置の作用を示すフローチャ
ート、 第7図は走行路面状態判別装置の作用を示すグラフ、 第8図は4輪操舵装置のコントローラの変形例のブロッ
ク図、 第9図はコントローラが舵角による転舵比制御を行う場
合における転舵比特性を示す図、 第10図は本発明による走行路面状態判別装置が設けられ
た車両の4輪操舵装置の他の例を示す概要図である。 28……走行路面状態判別装置 42……スリップ率検出部 43……駆動力係数検出部 44……記憶部 45……判別部FIG. 1 is a schematic diagram showing an example of a four-wheel steering system for a vehicle provided with a traveling road surface condition determining apparatus according to the present invention, FIG. 2 is a block diagram of a controller of the four-wheel steering system, and FIG. 4A and 4B are explanatory views for detecting drive torque, FIG. 5 is a block diagram showing a configuration of a traveling road surface state determination device, and FIG. FIG. 7 is a flow chart showing the operation of the traveling road surface state determination device, FIG. 7 is a graph showing the operation of the traveling road surface state determination device, FIG. 8 is a block diagram of a modified example of the controller of the four-wheel steering device, and FIG. 9 is the controller. FIG. 10 is a diagram showing a steering ratio characteristic when a steering ratio control is performed by a steering angle, and FIG. 10 is a schematic diagram showing another example of a four-wheel steering device for a vehicle provided with a traveling road surface state determination device according to the present invention. Is. 28 …… Running road surface condition discriminating device 42 …… Slip ratio detecting unit 43 …… Driving force coefficient detecting unit 44 …… Storage unit 45 …… Identifying unit
Claims (1)
面状態判別装置であって、 路面に対する駆動輪のスリップ率を検出するスリップ率
検出手段と、 車両の駆動装置の駆動力と前記駆動輪が受ける車軸荷重
の比を検出する駆動力係数検出手段と、 予め実験等により得られる特性であって、路面に対する
駆動輪のスリップ率と、車両の駆動装置の駆動力と駆動
輪が受ける車軸荷重の比との関係を、路面の摩擦係数を
パラメータとして示す少なくとも1つの駆動力係数特性
が記憶されている記憶手段と、 前記駆動力係数検出手段の検出信号から得られた駆動力
係数の値を、前記記憶手段に記憶されている駆動力係数
特性における、前記スリップ率検出手段の検出信号から
得られたスリップ率の値に対応する駆動力係数の値と比
較して、車両走行中の路面の摩擦係数の高低を判別する
判別手段とを備えていることを特徴とする走行路面状態
判別装置。1. A traveling road surface condition determining device for determining a condition of a road surface during traveling of a vehicle, comprising: slip ratio detecting means for detecting a slip ratio of a drive wheel with respect to the road surface; A driving force coefficient detecting means for detecting a ratio of an axle load received by the wheels, a characteristic obtained in advance by experiments, etc., that is, a slip ratio of the driving wheels with respect to a road surface, a driving force of a vehicle drive device and an axle received by the driving wheels. A storage unit that stores at least one driving force coefficient characteristic indicating a road ratio as a parameter, the relationship between the load ratio, and a value of the driving force coefficient obtained from the detection signal of the driving force coefficient detecting unit. Is compared with the value of the driving force coefficient corresponding to the value of the slip ratio obtained from the detection signal of the slip ratio detecting means in the driving force coefficient characteristic stored in the storage means, A traveling road surface state determination device, comprising: a determination unit that determines whether the friction coefficient of the road surface during traveling is high or low.
Priority Applications (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
JP61100140A JPH0640051B2 (en) | 1986-04-30 | 1986-04-30 | Road condition determination device |
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
JP61100140A JPH0640051B2 (en) | 1986-04-30 | 1986-04-30 | Road condition determination device |
Publications (2)
Publication Number | Publication Date |
---|---|
JPS62257043A JPS62257043A (en) | 1987-11-09 |
JPH0640051B2 true JPH0640051B2 (en) | 1994-05-25 |
Family
ID=14266011
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
JP61100140A Expired - Lifetime JPH0640051B2 (en) | 1986-04-30 | 1986-04-30 | Road condition determination device |
Country Status (1)
Country | Link |
---|---|
JP (1) | JPH0640051B2 (en) |
Cited By (1)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JP2016526499A (en) * | 2013-06-14 | 2016-09-05 | ピレリ・タイヤ・ソチエタ・ペル・アツィオーニ | Method and system for estimating possible friction between a vehicle tire and a rolling surface |
Families Citing this family (5)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
GB9004674D0 (en) * | 1990-03-02 | 1990-04-25 | Lucas Ind Plc | Method of and apparatus for controlling wheel spin |
JP2626226B2 (en) * | 1990-09-26 | 1997-07-02 | 日産自動車株式会社 | Four-wheel steering control device |
JP2020032850A (en) * | 2018-08-29 | 2020-03-05 | トヨタ自動車株式会社 | Vehicle control apparatus |
JP7434909B2 (en) * | 2020-01-10 | 2024-02-21 | 住友ゴム工業株式会社 | Road surface condition determination device, determination method, and determination program |
JP7396053B2 (en) * | 2020-01-10 | 2023-12-12 | 住友ゴム工業株式会社 | Tire slip ratio determination device, determination method, and determination program; road surface condition determination device, determination method, and determination program |
-
1986
- 1986-04-30 JP JP61100140A patent/JPH0640051B2/en not_active Expired - Lifetime
Cited By (2)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JP2016526499A (en) * | 2013-06-14 | 2016-09-05 | ピレリ・タイヤ・ソチエタ・ペル・アツィオーニ | Method and system for estimating possible friction between a vehicle tire and a rolling surface |
US9746414B2 (en) | 2013-06-14 | 2017-08-29 | Pirelli Tyre S.P.A. | Method and system for estimating the potential friction between a vehicle tyre and a rolling surface |
Also Published As
Publication number | Publication date |
---|---|
JPS62257043A (en) | 1987-11-09 |
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