JP2520144B2 - Rear wheel steering angle control device - Google Patents
Rear wheel steering angle control deviceInfo
- Publication number
- JP2520144B2 JP2520144B2 JP29989287A JP29989287A JP2520144B2 JP 2520144 B2 JP2520144 B2 JP 2520144B2 JP 29989287 A JP29989287 A JP 29989287A JP 29989287 A JP29989287 A JP 29989287A JP 2520144 B2 JP2520144 B2 JP 2520144B2
- Authority
- JP
- Japan
- Prior art keywords
- vehicle
- steering angle
- rear wheel
- center
- wheel
- 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
Classifications
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B62—LAND VEHICLES FOR TRAVELLING OTHERWISE THAN ON RAILS
- B62D—MOTOR VEHICLES; TRAILERS
- B62D7/00—Steering linkage; Stub axles or their mountings
- B62D7/06—Steering linkage; Stub axles or their mountings for individually-pivoted wheels, e.g. on king-pins
- B62D7/14—Steering linkage; Stub axles or their mountings for individually-pivoted wheels, e.g. on king-pins the pivotal axes being situated in more than one plane transverse to the longitudinal centre line of the vehicle, e.g. all-wheel steering
- B62D7/15—Steering linkage; Stub axles or their mountings for individually-pivoted wheels, e.g. on king-pins the pivotal axes being situated in more than one plane transverse to the longitudinal centre line of the vehicle, e.g. all-wheel steering characterised by means varying the ratio between the steering angles of the steered wheels
- B62D7/159—Steering linkage; Stub axles or their mountings for individually-pivoted wheels, e.g. on king-pins the pivotal axes being situated in more than one plane transverse to the longitudinal centre line of the vehicle, e.g. all-wheel steering characterised by means varying the ratio between the steering angles of the steered wheels characterised by computing methods or stabilisation processes or systems, e.g. responding to yaw rate, lateral wind, load, road condition
Landscapes
- Engineering & Computer Science (AREA)
- Physics & Mathematics (AREA)
- Mathematical Physics (AREA)
- Theoretical Computer Science (AREA)
- Chemical & Material Sciences (AREA)
- Combustion & Propulsion (AREA)
- Transportation (AREA)
- Mechanical Engineering (AREA)
- Steering-Linkage Mechanisms And Four-Wheel Steering (AREA)
- Steering Control In Accordance With Driving Conditions (AREA)
Description
【発明の詳細な説明】 （産業上の利用分野） 本発明は、車両の後輪舵角制御装置に関するものであ
る。The present invention relates to a rear wheel steering angle control device for a vehicle.
（従来の技術） この種の従来技術としては、例えば昭和62年６月５日
に社団法人自動車技術会が開催した「4WS（四輪操舵）
車：アクテイブ制御技術の最前線」シンポジウムの前刷
集第34〜41頁に記載されている「マツダ車速感応型四輪
操舵」に開示されているものがある。(Prior Art) As a conventional art of this kind, for example, “4WS (four-wheel steering)” held by the Society of Automotive Engineers of Japan on June 5, 1987.
Vehicles: Frontiers of active control technology "Mazda vehicle speed-sensitive four-wheel steering" described in pages 34-41 of the preprint of the symposium.
（発明が解決しようとする問題点） しかしながら、このような従来の後輪舵角制御装置に
あっては、車速を一定とすると、δr/δｆ＝一定となっ
ていたため、定常旋回での安定性は向上するが、緊急回
避的なハンドル操作およびスラローム走行等の動的なハ
ンドル操作を行なった場合に、車両の応答性に関して
は、向上代が少ないという問題点があった。(Problems to be Solved by the Invention) However, in such a conventional rear wheel steering angle control device, when the vehicle speed is constant, δ r / δ f = constant. Although the stability is improved, there has been a problem that there is little improvement margin regarding the responsiveness of the vehicle when the steering wheel operation for emergency avoidance and the dynamic steering wheel operation such as slalom traveling are performed.
（問題点を解決するための手段） 上述の問題点を解決するため本発明においては、車速
およびハンドル操舵角を検出して、前輪舵角δｆ（Ｓ）
に対して後輪舵角δｒ（Ｓ）を次式 に基づいて制御する装置において、車両の重心と重体の
横すべり角を０とする位置間の距離l3を車速に応じて変
化させて後輪制御を行う制御装置を設ける。(Means for Solving Problems) In order to solve the above problems, in the present invention, the vehicle speed and the steering angle of the steering wheel are detected to detect the front wheel steering angle δ f (S).
For the rear wheel steering angle δ r (S), In the control device based on (1), a control device is provided for performing rear wheel control by changing the distance l 3 between the center of gravity of the vehicle and the position where the side slip angle of the body is 0 according to the vehicle speed.
（作 用） 上述のように、本発明によれば、δｒ（Ｓ）／δ
ｆ（Ｓ）の伝達関数を１次/1次の形として、車体の横す
べり角が０となる位置を所定の範囲に設定して後輪制御
を行なうようにしたため、ハンドル操舵に対する車両の
応答性、安定性が向上する。(Operation) As described above, according to the present invention, δ r (S) / δ
Since the transfer function of f (S) is of linear or linear form and the position where the side slip angle of the vehicle body is 0 is set within a predetermined range to control the rear wheels, the responsiveness of the vehicle to the steering of the steering wheel , Stability is improved.
特に本発明においては、車両の重心と車体の横すべり
角を０とする位置間の距離l3を車速に応じて変化させる
ようにしたから、低速機敏性と中高速応答安定性を高次
元で両立させることができる。In particular, in the present invention, the distance l 3 between the center of gravity of the vehicle and the position where the side slip angle of the vehicle body is set to 0 is changed according to the vehicle speed, so that low-speed agility and medium-to-high-speed response stability are achieved at a high level. Can be made.
（実施例） 以下、図面について本発明を詳細に説明する。第１図
は本発明の説明用平面図であり、図中１は前輪、２は後
輪、３はステアリングホイール、ｇは車両の重心であ
る。また図における各符号は次の通りである。(Example) Hereinafter, the present invention will be described in detail with reference to the drawings. FIG. 1 is a plan view for explaining the present invention, in which 1 is a front wheel, 2 is a rear wheel, 3 is a steering wheel, and g is a center of gravity of the vehicle. Moreover, each code | symbol in a figure is as follows.
M:車両重量 I:ヨー慣性モーメント l:ホイールベース a:車両の重心と前輪中心間の距離 b:車両の重心と後輪中心間の距離 l3:車両の重心と車体の横すべり角を０とする位置間の
距離 F1:前輪横力（２輪分） F2:後輪横力（２輪分） C1:前輪のコーナリングパワー（２輪分） C2:後輪のコーナリングパワー（２輪分） β1:前輪タイヤの横すべり角 β2:後輪タイヤの横すべり角 V:車速。M: vehicle weight I: yaw moment of inertia l: wheel base a: distance between the center of gravity of the vehicle and the center of the front wheels b: distance between the center of gravity of the vehicle and the center of the rear wheels l 3 : 0 for the center of gravity of the vehicle and the sideslip angle of the vehicle body the distance between the positions F 1: front wheel lateral force (two wheels min) F 2: rear wheel lateral force (two wheels min) C 1: cornering power (two-wheel min) of the front wheel C 2: rear wheel cornering power (2 Wheels) β 1 : Side slip angle of front tires β 2 : Side slip angle of rear tires V: Vehicle speed.
v:横移動速度 ω：ヨーレイト N:ステアリングギヤ比 第１図に示す線型２自由度モデルにおいて、運動方程
式をラプラス変換した形で表わすと、 ここでδ１＝θ/N（前輪操舵角），δ２を後輪操舵角
とすると、 いま重心点後方l3の距離での横移動速度をv3とする
と、 v3＝ｖ−l3ω … で表わされる。v: lateral movement speed ω: yaw rate N: steering gear ratio In the linear two-degree-of-freedom model shown in Fig. 1, when the equation of motion is expressed in Laplace transform, If δ 1 = θ / N (front wheel steering angle) and δ 2 is the rear wheel steering angle, If the lateral moving speed at the distance l 3 behind the center of gravity is v 3 , then v 3 = v−l 3 ω ...
ここでl3の位置で横移動速度v3が０となるように、後
輪を操出する時の後輪操出制御関数を求める。As here the traverse speed v 3 is 0 at the position of the l 3, the rear wheel seek wheel Feeding control function after the time of output steering.
v3＝０より ｖ＝l3ω … となる。これを前述の〜に代入すると、 の関係式が得られる。From v 3 = 0, v = l 3 ω ... Substituting this into ~ above, The relational expression of is obtained.
前輪舵角δ１に応動して後輪舵角δ２をδ２（Ｓ）＝
Ｇ（Ｓ）・δ１（Ｓ）となる伝達関数Ｇ（Ｓ）によって
制御を行なう場合に、上述の式を用いてＧ（Ｓ）を求め
ることができる。In response to the front wheel steering angle δ 1 , the rear wheel steering angle δ 2 is changed to δ 2 (S) =
When control is performed by the transfer function G (S) that is G (S) · δ 1 (S), G (S) can be obtained using the above equation.
ω，δ１でまとめ直して、 左側の項｛ ｝内をそれぞれA,BとしてＧを求める
と、 ここで、 従って、 ハンドル操舵角に対するヨーレイト特性は、 ここで とすれば、式は下記のようになる。 Re-assemble with ω and δ 1 , When G is calculated with A and B in the left-side term {}, respectively, here, Therefore, The yaw rate characteristic with respect to the steering angle is here Then, the formula becomes as follows.
したがって本発明においては、車速およびハンドル操
舵角を検出して、前輪舵角δｆ（Ｓ）に対して後輪舵角
δｒ（Ｓ）を次式 に基づいて制御するようにすると共に、特に車両の重心
と車体の横すべり角を０とする位置間の距離l3を車速に
応じて変化させて後輪制御を行うようにする。 Therefore, in the present invention, the vehicle speed and the steering angle of the steering wheel are detected, and the rear wheel steering angle δ r (S) is calculated by the following equation with respect to the front wheel steering angle δ f (S). And the rear wheel control is performed by changing the distance l 3 between the center of gravity of the vehicle and the position where the side slip angle of the vehicle body is zero according to the vehicle speed.
第２図および第３図は本発明を実施する車両およびそ
の制御装置の一例を示すものである。図中1L,1Rは夫々
左右前輪、2L,2Rは夫々左右後輪である。前輪1L,1Rを夫
々ステアリングホイール３によりステアリングギヤ４を
介して転舵可能とし、前輪舵角δｆはステアリングホイ
ール操舵角をθ、ステアリングギヤ比をＮとすると、δ
ｆ＝θ/Nで表わされる。トランスバースリンク5L,5Rお
よびアッパーアーム6L,6Rを含むリヤサスペンション装
置により車体のリヤサスペンションメンバ７に懸架され
た後輪2L,2Rも転舵可能とし、この目的のため、後輪の
ナックルアーム8L,8R間をアクチュエータ９及びその両
端におけるサイドロッド10L,10Rにより相互に連結す
る。FIG. 2 and FIG. 3 show an example of a vehicle and a control device therefor embodying the present invention. In the figure, 1L and 1R are left and right front wheels respectively, and 2L and 2R are left and right rear wheels respectively. When the front wheels 1L and 1R can be steered by the steering wheel 3 via the steering gear 4, the front wheel steering angle δ f is δ, where θ is the steering wheel steering angle and N is the steering gear ratio.
It is represented by f = θ / N. The rear suspension device including the transverse links 5L, 5R and the upper arms 6L, 6R also enables the rear wheels 2L, 2R suspended on the rear suspension member 7 of the vehicle body to be steered. For this purpose, the rear wheel knuckle arm 8L is used. , 8R are connected to each other by the actuator 9 and side rods 10L, 10R at both ends thereof.
アクチュエータ９はスプリングセンタ式復動液圧シリ
ンダとし、その２室を夫々管路11L,11Rにより電磁比例
式圧力制御弁12に接続する。この制御弁12には更にポン
プ13及びリザーバタンク14を含む液圧源の液圧管路15及
びドレン管路16を夫々接続する。制御弁12はスプリング
センタ式３位置弁とし、両ソレノイド12L,12RのOFF時管
路11L,11Rを無圧状態にし、ソレノイド12LのON時通電量
に比例した圧力を管路11Lに供給し、ソレノイド12RのON
時通電量に比例した圧力を管路11Rに供給するものとす
る。The actuator 9 is a spring-centered backward hydraulic cylinder, and its two chambers are connected to the electromagnetic proportional pressure control valve 12 by pipe lines 11L and 11R, respectively. The control valve 12 is further connected to a hydraulic line 15 and a drain line 16 of a hydraulic source including a pump 13 and a reservoir tank 14, respectively. The control valve 12 is a spring center type 3-position valve, the solenoid lines 12L and 12R are in the OFF state when the pipe lines 11L and 11R are in a non-pressurized state, and a pressure proportional to the energization amount of the solenoid 12L when ON is supplied to the pipe line 11L. Turn on solenoid 12R
It is assumed that the pressure proportional to the hourly current amount is supplied to the pipeline 11R.
ソレノイド12L,12RのON,OFF及び通電量はコントロー
ラ17により電子制御し、このコントローラ17は第３図に
示す如くデジタル演算回路17aと、デジタル入力検出回
路17bと、記憶回路17cと、D/A変換器17dと、駆動回路17
eとで構成する。コントローラ17には、ステアリングホ
イール３の操舵角θを検出する操舵角センサ18からの信
号、及び車速Ｖを検出する車速センサ19からの信号を夫
々デジタル入力検出回路17bを経て入力する。コントロ
ーラ17のデジタル演算回路17aはこれら入力情報及び記
憶回路17cの格納定数を基に前記式を演算し、演算結
果に対応した後輪舵角δｒに関するデジタル信号をD/A
変換器17dによりアナログ信号に変換する。このアナロ
グ信号は駆動回路17eにより後輪舵角δｒに対応した電
流ｉに変換され、制御弁12に供給される。The ON / OFF and energizing amounts of the solenoids 12L and 12R are electronically controlled by a controller 17, and the controller 17 includes a digital operation circuit 17a, a digital input detection circuit 17b, a storage circuit 17c, and a D / A as shown in FIG. Converter 17d and drive circuit 17
and e. A signal from the steering angle sensor 18 that detects the steering angle θ of the steering wheel 3 and a signal from the vehicle speed sensor 19 that detects the vehicle speed V are input to the controller 17 via the digital input detection circuit 17b. The digital calculation circuit 17a of the controller 17 calculates the above formula based on the input information and the storage constant of the storage circuit 17c, and outputs the digital signal regarding the rear wheel steering angle δ r corresponding to the calculation result to the D / A.
The converter 17d converts the analog signal. This analog signal is converted by the drive circuit 17e into a current i corresponding to the rear wheel steering angle δ r and supplied to the control valve 12.
この際コントローラ17は制御弁の12のいずれのソレノ
イド12L又は12Rに電流ｉを供給すべきかを操舵角θから
決定し、対応する管路11L又は11Rに電流ｉ（演算後輪舵
角δｒ）に応じた液圧を発生させる。アクチュエータ９
はこの液圧に応じた方向へ又この液圧に応じた距離だけ
ストロークし、サイドロッド10L及び10Rを介し後輪2L及
び2Rを対応方向へ演算結果に応じた角度だけ転舵するこ
とができる。At this time, the controller 17 determines which solenoid 12L or 12R of the control valve 12 should be supplied with the current i from the steering angle θ, and the current i (calculated rear wheel steering angle δ r ) is supplied to the corresponding pipeline 11L or 11R. To generate a hydraulic pressure corresponding to. Actuator 9
Strokes in a direction corresponding to this hydraulic pressure and a distance corresponding to this hydraulic pressure, and can steer the rear wheels 2L and 2R through the side rods 10L and 10R in the corresponding direction by an angle corresponding to the calculation result. .
次に作用を説明する。l3を車速に応じて変化させるこ
とにより様々な車両特性を得ることができるようになる
が、下記の例はその一例を示すものである。Next, the operation will be described. Various vehicle characteristics can be obtained by changing l 3 according to the vehicle speed, and the following example shows one example.
すなわち、低速機敏性を増すため、低速時はl3を重心
点位置より前方に持って来るようにし、車速が高まるに
つれて安定性を確保するため、徐々にl3を後方側へずら
していくようにする。That is, to increase the low-speed agility, low speed is to bring forward the center of gravity point position l 3, in order to ensure stability as the vehicle speed increases gradually as by shifting the l 3 rearward To
第４図は本発明の実施例におけるK,T1,T2の車速依存
性を表わしたグラフを示すものである。FIG. 4 is a graph showing the vehicle speed dependence of K, T1, T2 in the embodiment of the present invention.
また第５図はl3の車速による変化を表わしたグラフを
示すものである。FIG. 5 is a graph showing the change of l 3 with the vehicle speed.
（発明の効果） 以上説明してきたように、本発明によれば、δ
ｒ（ｓ）／δｆ（ｓ）の伝達関数を１次/1次の形とし
て、車体の横すべり角が０となる位置を所定の範囲に設
定して後輪制御を行なうようにしたため、ハンドル操舵
に対する車両の応答性、安定性が向上する。(Effects of the Invention) As described above, according to the present invention,
Since the transfer function of r (s) / δ f (s) is of a first-order / first-order form, the position where the side slip angle of the vehicle body is 0 is set within a predetermined range to control the rear wheels. The responsiveness and stability of the vehicle to steering is improved.
特に本発明においては、車両の重心と車体の横すべり
角を０とする位置間の距離l3を車速に応じて変化させる
ようにしたから、低速機敏性と中高速応答安定性を高次
元で両立させることができるという効果も得られる。In particular, in the present invention, the distance l 3 between the center of gravity of the vehicle and the position where the side slip angle of the vehicle body is set to 0 is changed according to the vehicle speed, so that low-speed agility and medium-to-high-speed response stability are achieved at a high level. The effect that it can be obtained is also obtained.
第１図は本発明の説明用平面図、 第２図は本発明を適用する車両の制御装置図、 第３図はその制御装置のブロック線図、 第４図および第５図は本発明の説明用の各種特性図であ
る。 1,1L,1R……前輪、2,2L,2R……後輪 ３……ステアリングホイール ４……ステアリングギヤ 5L,5R……トランスバースリンク 6L,6R……アッパアーム ７……リヤサスペンションメンバ ９……アクチュエータ 12……電磁比例式圧力制御弁 17……コントローラ、18……操舵角センサ 19……車速センサFIG. 1 is a plan view for explaining the present invention, FIG. 2 is a control device diagram of a vehicle to which the present invention is applied, FIG. 3 is a block diagram of the control device, and FIGS. 4 and 5 show the present invention. It is various characteristic diagrams for explanation. 1,1L, 1R …… front wheel, 2,2L, 2R …… rear wheel 3 …… steering wheel 4 …… steering gear 5L, 5R …… transverse link 6L, 6R …… upper arm 7 …… rear suspension member 9 ・ ・ ・… Actuator 12 …… Electromagnetic proportional pressure control valve 17 …… Controller, 18 …… Steering angle sensor 19 …… Vehicle speed sensor
Claims (1)
輪舵角δｆ（Ｓ）に対して後輪舵角δｒ（Ｓ）を次式 に基づいて制御する装置において、車両の重心と車体の
横すべり角を０とする位置間の距離l3（後輪方向をプラ
スとする）を車速に応じて変化させて後輪制御を行う制
御装置を設けることを特徴とする後輪舵角制御装置。但
し、S:ラプラス演算子 K,T1、T2:制御定数 M:車両重量 I:ヨー慣性モーメント l:ホイールベース a:車両の重心と前輪中心間の距離 b:車両の重心と後輪中心間の距離 C1:前輪のコーナリングパワー（２輪分） C2:後輪のコーナリングパアー（２輪分） V:車速。1. A vehicle speed and a steering angle of a steering wheel are detected, and a rear wheel steering angle δ r (S) is calculated with respect to a front wheel steering angle δ f (S) as follows. In a device for controlling rear wheels, a controller for controlling rear wheels by changing a distance l 3 (a rear wheel direction is positive) between a center of gravity of a vehicle and a position where a sideslip angle of a vehicle body is 0 according to a vehicle speed. A rear wheel steering angle control device comprising: However, S: Laplace operator K, T1, T2: Control constant M: Vehicle weight I: Yaw moment of inertia l: Wheel base a: Distance between the center of gravity of the vehicle and the center of the front wheels b: Distance between the center of gravity of the vehicle and the center of the rear wheels C 1 : Front cornering power (for two wheels) C 2 : Rear wheel cornering power (for 2 wheels) V: Vehicle speed.
Priority Applications (2)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP29989287A JP2520144B2 (en) | 1987-11-30 | 1987-11-30 | Rear wheel steering angle control device |
| US07/277,745 US4947326A (en) | 1987-11-30 | 1988-11-30 | Rear wheel steer angle control system for vehicle |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP29989287A JP2520144B2 (en) | 1987-11-30 | 1987-11-30 | Rear wheel steering angle control device |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPH01145273A JPH01145273A (en) | 1989-06-07 |
| JP2520144B2 true JP2520144B2 (en) | 1996-07-31 |
Family
ID=17878196
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP29989287A Expired - Lifetime JP2520144B2 (en) | 1987-11-30 | 1987-11-30 | Rear wheel steering angle control device |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JP2520144B2 (en) |
Cited By (1)
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| US20230044869A1 (en) * | 2021-07-22 | 2023-02-09 | GM Global Technology Operations LLC | Vehicle actuation commands to affect transient handling |
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| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP4606861B2 (en) * | 2004-12-03 | 2011-01-05 | 本田技研工業株式会社 | Vehicle state detection device |
| JP4639985B2 (en) * | 2005-06-22 | 2011-02-23 | トヨタ自動車株式会社 | Vehicle steering control device |
| JP5321107B2 (en) * | 2009-02-06 | 2013-10-23 | 日産自動車株式会社 | Turning behavior control device and turning behavior control method |
-
1987
- 1987-11-30 JP JP29989287A patent/JP2520144B2/en not_active Expired - Lifetime
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US20230044869A1 (en) * | 2021-07-22 | 2023-02-09 | GM Global Technology Operations LLC | Vehicle actuation commands to affect transient handling |
| US11724739B2 (en) * | 2021-07-22 | 2023-08-15 | GM Global Technology Operations LLC | Vehicle actuation commands to affect transient handling |
Also Published As
| Publication number | Publication date |
|---|---|
| JPH01145273A (en) | 1989-06-07 |
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