JP3779440B2 - Vehicle control device - Google Patents

Description

【００２２】
つまり接地荷重Ｗは、ばね上慣性力とばね下慣性力との和となるので、アクチュエータ５の伸縮加速度を制御してばね上質量とばね下質量との少なくともいずれか一方の慣性力を変化させることにより、接地荷重Ｗを変化させることができる。従って、アクチュエータ５の伸張加速度を制御することにより、接地荷重Ｗをタイヤ毎に一時的に増大させることが可能となる。なお、サスペンションストロークを２００mmとしてアクチュエータ５に１トンの推力を発生させた場合、約０．２秒間作動させることができる。
【００２３】
例えば、前輪駆動車の発進・加速の場合、通常でも前輪荷重が後輪荷重よりもやや大きいが（図３（ａ））、上記の手法で前輪の接地荷重を通常時に比して一時的に増大させることにより（図３（ｂ））、前輪のグリップ力が向上し、加速性能が向上する。また、同様に後輪駆動車の発進・加速の場合には図４（ａ）に示すように上記の手法で後輪の接地荷重を通常時に比して一時的に増大させ、４輪駆動車の場合には図４（ｂ）に示すように前後輪のすべての車輪の接地荷重を通常時に比して一時的に増大させることにより、駆動輪のグリップ力が向上し、加速性能が向上する。
【００２４】
一方、車両の旋回時には図５に示すように、後輪の接地荷重が小さくなり、外側にスピンする傾向にあるが、後輪の接地荷重を各輪の現在の接地荷重に応じて通常時に比して一時的に増大させることにより、各車輪のグリップ力が向上し、旋回性能が向上する。図示したものは前輪駆動車であるが、後輪駆動車、４輪駆動車についてもその程度は異なるもののこれと同様である。
【００２５】
ここで、上記各図は一般的な接地荷重分布の場合について説明したが、例えば前輪駆動車の後輪寄りに比較的重量物を積載した場合など、その荷重分布が変化した場合には荷重センサにてこれを検知し、その分布に応じて各車輪の接地荷重を増大させると良い。
【００２６】
なお、図３、図４及び図５は、タイヤの接地荷重（＝グリップ力）分布を概念的に示し、静荷重の範囲での接地荷重を実線の円で表し、アクチュエータ５のストローク制御で増大した接地荷重を二点鎖線の円で表している。
【００２７】
一般的には、アクチュエータの消費エネルギを節約するために車両重量を支持する懸架スプリングと減衰力発生用ダンパとを併用するが（図６参照）、その場合は、
Ｋs：懸架スプリングのばね定数
Ｃ：ダンパの減衰係数
とすると、ばね上質量Ｍ2並びにばね下質量Ｍ1の運動方程式は、それぞれ次式で与えられる。
Ｍ2・Ｚ2^**＋Ｃ・（Ｚ2^*−Ｚ1^*）＋Ｋs・（Ｚ2−Ｚ1）＝−Ｆz
Ｍ1・Ｚ1^**＋Ｃ・（Ｚ1^*−Ｚ2^*）＋Ｋs・（Ｚ1−Ｚ2）＋Ｋt・Ｚ1＝Ｆz
【００２８】
従って、タイヤ接地荷重Ｗは次式で与えられる。

【００２９】
つまり接地荷重Ｗは、上記と同様に、アクチュエータの伸縮加速度を制御することによって変化させることができることが分かる。
【００３０】
実際の車両の慣性力は、上下方向運動のみならず、ローリング運動およびピッチング運動によっても発生する。ここでばね上質量の重心点を通る各軸回りの回転運動を、
ロールレイト：φ
ピッチレイト：θ
ヨーレイト：γ
とし、重心位置を基準とした前後方向中心線と左右方向中心線から各輪の接地中心までの距離をそれぞれＬf、Ｌr、Ｔf／２、Ｔr／２とし（図７参照）、各輪のアクチュエータの推力を、Ｆz1（前左）、Ｆz2（前右）、Ｆz3（後右）、Ｆz4（後左）とし、力、モーメント、並びに座標系の向きを図８に示すものとすれば、ローリングモーメントは、
Ｍx＝Ｔf／２・（−Ｆz1＋Ｆz2）−Ｔf／２・（−Ｆz3＋Ｆz4）
となり、ピッチングモーメントは、
Ｍy＝Ｌf・（−Ｆz1−Ｆz2）−Ｌr・（−Ｆz3−Ｆz4）
となる。
【００３１】
また、
ローリング慣性モーメント：Ｉx
ピッチング慣性モーメント：Ｉy
とすれば、
ローリング慣性力は、
Ｉxφ^*＝Ｍx
＝Ｔf／２・（−Ｆz1＋Ｆz2）−Ｔf／２・（−Ｆz3＋Ｆz4）
となり、ピッチング慣性力は

となる。
【００３２】
さらに上下運動の慣性力は、
Ｍ2・Ｚ2^**＝−Ｆz1−Ｆz2−Ｆz3−Ｆz4
となり、これらの慣性力の少なくとも１つを制御することにより、ローリング運動およびピッチング運動を含む場合の接地荷重も、各タイヤについて個々に制御することで、一層急加速時の安定性が向上する。なお、従来のものは、４輪に荷重を配分するため、ローリング慣性力、ピッチング慣性力、並びに上下運動の慣性力は発生せず、これらの値は０となる。
【００３３】
尚、トラクション制御装置の作動要領については公知であることからその詳細な説明を省略する。
【００３４】
次に、駆動輪空転検出部２７による空転予測、検出処理について説明する。まず、車輪速センサ２８、車速センサ２９、前後方向加速度センサ３０、スロットル開度センサ３１、エンジン回転速度センサ３２、シフトポジションセンサ３３、操舵角センサ３４、ヨーレートセンサ３５及び横加速度センサ３６から信号を読み込み、これらに基づき、予め設定されている各データのテーブルと比較してまたは所定の式に各データを当てはめて車両の状態を駆動輪空転検出部２７にて判断し、各車輪の空転を予測し、または既に空転しているか否かを判断する。そして、空転するまたは空転していると判断されたら、路面摩擦係数μを考慮して増加させる接地荷重、即ち付勢接地荷重を算定し、上記した手法により実際に接地荷重を増加させることとなる。ここで、路面摩擦係数μは、上記各検出値、操舵反力等から算定すると良い。
【００３５】
尚、上記実施例は、アクチュエータとして油圧駆動のシリンダ装置を用いるものを示したが、これはリニアモータ或いはボイスコイルなどの如きその他の電気式の推力発生手段を用いても、あるいはカム機構やばね手段を用いて加速度を発生させても、同様の効果を得ることもできる。
【００３６】
また、本発明の要旨を逸脱しない範囲で使用センサを簡略化することもできる。例えば、ばね上、ばね下両加速度センサの出力差を二階積分することでも位置検出信号を得ることができるので、ストロークセンサを廃止することができるし、ばね上、ばね下両重量の実測値と、ばね上、ばね下両加速度センサの出力値とを演算することでアクチュエータが発生する力を求めることができるので、荷重センサを廃止することもできる。さらに、荷重センサと変位センサとの信号に基づいて状態推定器を構成し、ばね上、ばね下両加速度を間接的に求めることもできる。さらにＥＣＵについても、ディジタル、アナログ、またはハイブリッドのいずれでも実現可能なことは言うまでもない。
【００３７】
【発明の効果】
このように本発明によれば、加速時、旋回時に車輪の空転が予測または検知されたら、車体と車軸との間に設けたアクチュエータの伸長加速度で車体に上下方向の慣性力を発生させ、その反力を接地面に作用させることにより、タイヤの接地荷重を一時的に増大させ、タイヤのグリップ力の発生限界を高めることができ、安定に効率良く加速または旋回することが可能となる。また、これとトラクション制御装置を組み合わせ、協働させることにより、一層効率良く加速または旋回することができる。このとき、車輪の空転予測または検出に用いるセンサ、判断手段を共通化することで、構造が簡単になり、部品点数が削減される。
【図面の簡単な説明】
【図１】本発明が適用される能動型懸架装置の概略システム構成図。
【図２】本発明の原理を説明するためのモデル図。
【図３】（ａ）は従来の前輪駆動車の発進時の概念的な接地荷重分布図、（ｂ）は本発明が適用された前輪駆動車の発進時の概念的な接地荷重分布図。
【図４】（ａ）は本発明が適用された後輪駆動車の発進時の概念的な接地荷重分布図、（ｂ）は本発明が適用された４輪駆動車の発進時の概念的な接地荷重分布図。
【図５】本発明が適用された前輪駆動車の旋回時の概念的な接地荷重分布図。
【図６】一般的な能動型懸架装置のモデル図。
【図７】車体重心位置と接地位置との関係を示す説明図。
【図８】力、モーメント、並びに座標系の向きの関係を示す説明図。
【符号の説明】
１ タイヤ
２ 上サスペンションアーム
３ 下サスペンションアーム
４ 車体
５ アクチュエータ
６ ピストン
７・８ 油室
９ 油圧ポンプ
１０ サーボ弁
１１ ピストンロッド
１２ アキュムレータ
１３ アンロード弁
１４ オイルフィルタ
１５ 逆止弁
１６ 圧力調整弁
１７ オイルクーラ
１８ 電子制御ユニット（ＥＣＵ）
１９ サーボ弁ドライバ
２０ 荷重センサ
２１ ストロークセンサ
２２ ばね上加速度センサ
２３ ばね下加速度センサ
２４ 目標荷重演算部
２５ 安定化演算部
２６ 変位制限比較演算部
２７ 駆動輪空転予測部
２８ 車輪速センサ
２９ 車速センサ
３０ 前後方向加速度センサ
３１ スロットル開度センサ
３２ エンジン回転速度センサ
３３ シフトポジションセンサ
３４ 操舵角センサ
３５ ヨーレートセンサ
３６ 横加速度センサ
３７ スロットル開度制御装置[0001]
BACKGROUND OF THE INVENTION
The present invention generates an inertial force in the vertical direction on the vehicle body by the extension acceleration of the actuator that actively changes the vertical relative distance between the vehicle body and the axle, and temporarily increases the ground load by the reaction force. In particular, the vehicle control apparatus includes a grounding load control means capable of driving the wheel and a traction control means for controlling the driving force generated by the wheels to be near a peak value determined by the slip ratio between the tire and the road surface. Further, the present invention relates to a vehicle control device that can contribute to improvement of turning performance.
[0002]
[Prior art]
Conventionally, as disclosed in, for example, Japanese Patent Laid-Open No. 5-214974, the driving force generated by a tire at the time of sudden acceleration such as when the vehicle starts is near the peak value determined by the slip ratio between the tire and the road surface. 2. Description of the Related Art A traction control device that is controlled so that the tires are controlled so that the tires are not slipped and stably and efficiently accelerated is well known.
[0003]
On the other hand, a linear sliding actuator capable of actively changing the stroke is provided between the vehicle body and the axle, and the ground load distribution of each tire according to the motion state of the vehicle at that time becomes a predetermined target value. Thus, an active suspension system in which the actuator stroke is feedback-controlled has already been put into practical use.
[0004]
For example, a conventional active suspension system such as that proposed in Japanese Patent Publication No. 60-5000662 basically controls the thrust (stroke) of the hydraulic actuator so as to suppress a change in the posture of the vehicle body during traveling. Controls the amount of load movement between the front and rear axles so that when the vehicle goes straight, the tire follows the unevenness of the road surface to suppress changes in the center of gravity of the sprung mass and to suppress pitching during braking and acceleration. In general, the amount of load movement between tires is controlled so as to suppress rolling during turning.
[0005]
[Problems to be solved by the invention]
Incidentally, the grip force F of the tire is given by the product (F = μW) of the coefficient of friction μ between the tire and the road surface and the vertical load W applied to the ground contact surface of the tire. That is, it can be said that the grip force of a tire that greatly affects the mobility of the vehicle is proportional to the contact load if the coefficient of friction between the tire and the road surface is constant.
[0006]
However, in the traction control device as described above, since the ground contact load is constant, the driving force distribution of each wheel according to the vehicle behavior at that time can be optimized within the range of the friction coefficient determined by the road surface and the tire. However, it was not possible to further increase the tire grip margin.
[0007]
Similarly, in the active suspension system as described above, the load distribution of each wheel according to the vehicle behavior at that time can be optimized within the range of the vehicle weight, and the tire grip exceeds the range of the vehicle weight. It was not possible to further increase the power margin.
[0008]
The present invention has been devised in order to solve the problems imposed on the prior art as described above, and its main purpose is to obtain a stable and high performance especially at the time of acceleration such as at the time of starting or turning. An object of the present invention is to provide a vehicle control device that can perform the above-described operation.
[0009]
[Means for Solving the Problems]
To achieve the above objects, in the present invention generates an inertial force in the vertical direction on the vehicle body in a stretched acceleration of the actuator provided between the vehicle body and the axle, temporary ground contact load of the tire by the reaction force A ground load control means for increasing the speed, a wheel idling detection means for predicting that one of the wheels is idle and / or detecting that the wheel is idling at the time of starting or traveling, and a drive generated by the wheel A vehicle control device having a traction control means for controlling the force so as to be in the vicinity of a peak value determined by a slip ratio between the tire and the road surface, the wheel idling detection means predicts that the wheel idling and / or the wheel When it is detected that the vehicle is idling, the wheel contact load increasing control by the ground load control means is prioritized over the wheel driving force control by the traction control means. And shall and performing.
[0010]
According to this, since a load exceeding the vehicle weight can be temporarily applied to the tire contact surface, the generation limit of the grip force of the tire can be raised as desired, and temporary acceleration such as when starting Performance and turning performance are improved. In addition, acceleration performance and turning performance are optimized by appropriately controlling the driving force of the tire. At this time, the occurrence of tire slip is detected by a common sensor and judged by a common judgment device, whereby the structure is simplified and the number of parts can be reduced.
[0011]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, a configuration of the present invention will be described in detail with reference to the accompanying drawings.
[0012]
FIG. 1 schematically shows a schematic configuration of a main part of an active suspension device for a vehicle to which the present invention is applied. The tire 1 is supported by upper and lower suspension arms 2 and 3 so as to be movable up and down with respect to the vehicle body 4. A hydraulic actuator linear actuator 5 is provided between the lower suspension arm 3 and the vehicle body 4.
[0013]
The linear actuator 5 is of the cylinder / piston type, and the hydraulic pressure supplied from the variable displacement hydraulic pump 9 to the upper and lower oil chambers 7 and 8 of the piston 6 inserted in the cylinder is controlled by the servo valve 10. As a result, a vertical thrust is generated in the piston rod 11, whereby the relative distance between the center (axle) of the tire 1 and the vehicle body 4 can be freely changed.
[0014]
The oil discharged from the pump 9 is stored in an accumulator 12 for removing pump pulsation and securing the oil amount in a transient state, and then individually to each actuator 5 with respect to the actuator 5 provided on each wheel. It is supplied via a provided servo valve 10.
[0015]
An unload valve 13, an oil filter 14, a check valve 15, a pressure adjustment valve 16, an oil cooler 17, and the like are connected to this hydraulic circuit as in a known active suspension system.
[0016]
The servo valve 10 continuously controls the hydraulic pressure and direction applied to the hydraulic actuator 5 by providing a control signal generated from an electronic control unit (ECU) 18 to the solenoid 10a via the servo valve driver 19. A load sensor 20 provided at a connection portion between the vehicle body 4 and the piston rod 11, a stroke sensor 21 provided between the vehicle body 4 and the lower suspension arm 3, and a sprung for detecting vertical acceleration on the vehicle body side. The acceleration sensor 22 and the unsprung acceleration sensor 23 that detects the vertical acceleration on the tire side are controlled based on signals processed by the ECU 18.
[0017]
The ECU 18 includes a wheel idling detection unit 27, a target load calculation unit 24, a stabilization calculation unit 25, and a displacement limit comparison calculation unit 26. A wheel speed sensor 28 provided on the drive wheel, a vehicle speed sensor 29 provided on the driven wheel, a longitudinal acceleration sensor 30, a throttle opening sensor 31, an engine rotation speed sensor 32, a shift position sensor 33, and a steering angle sensor 34 are provided. , A slip prediction signal or slip detection signal generated in the wheel slip detection unit 27 based on signals from the yaw rate sensor 35 and the lateral acceleration sensor 36, a signal from the sprung acceleration sensor 22, and a signal from the unsprung acceleration sensor 23 The target load calculation unit 24 obtains a temporary target load, the difference between this value and the signal of the load sensor 20 is processed by the stabilization calculation unit 25, and then the displacement limit comparison calculation unit 26 performs the stroke sensor. The servo valve driver 19 is given with reference to the signal 21 so that the control is performed within the stroke range of the actuator 5. To adjust the decree value. In response to the adjusted command signal, the servo valve 10 is driven so that the target load and the actual load are equal to generate an extension acceleration in the actuator 5, and the reaction force of the vertical inertia force acting on the vehicle body at that time increase the tire contact patch load by.
[0018]
The wheel idling detection unit 27 is also connected to a throttle opening degree control device 37 constituting a traction control device, and controls the throttle opening degree to be suppressed based on the idling prediction signal or idling detection signal.
[0019]
Here, if wheel slippage is predicted or detected by the wheel idling detection unit 27, the throttle opening may be suppressed simultaneously with increasing the tire grounding load. First, the tire grounding load is increased. If the control is performed so as to suppress the throttle opening when the idling of the wheel is still predicted or detected, the vehicle can be accelerated or turned most efficiently.
[0020]
Next, the principle of temporarily increasing the ground load will be described. In the model of FIG.
M2: Unsprung mass M1: Unsprung mass Z2: Unsprung coordinate Z1: Unsprung coordinate Kt: Spring constant of tire Fz: Actuator thrust, where the downward direction is positive, the motion of unsprung mass M2 and unsprung mass M1 Each equation is given by the following equation. However, the ^* mark in the formula represents the first derivative, and the ^** mark represents the second derivative.
M2 ・ Z2 ^** = −Fz
M1 ・ Z1 ^** + Kt ・ Z1 ＝ Fz
[0021]
Therefore, the tire ground contact load W is given by the following equation.

[0022]
That is, since the ground load W is the sum of the sprung inertia force and the unsprung inertia force, the inertial force of the sprung mass or the unsprung mass is changed by controlling the expansion / contraction acceleration of the actuator 5. As a result, the ground load W can be changed. Therefore, the ground load W can be temporarily increased for each tire by controlling the extension acceleration of the actuator 5. When the suspension stroke is 200 mm and a thrust of 1 ton is generated in the actuator 5, it can be operated for about 0.2 seconds.
[0023]
For example, in the case of start / acceleration of a front wheel drive vehicle, the front wheel load is usually slightly larger than the rear wheel load (FIG. 3 (a)), but the ground contact load of the front wheel is temporarily compared to the normal time by the above method. By increasing (FIG. 3 (b)), the grip force of the front wheels is improved and the acceleration performance is improved. Similarly, when starting and accelerating the rear wheel drive vehicle, as shown in FIG. 4 (a), the ground contact load of the rear wheel is temporarily increased by the above method as compared with the normal time, and the four wheel drive vehicle is In this case, as shown in FIG. 4 (b), the grounding load of all the front and rear wheels is temporarily increased as compared with the normal time, thereby improving the grip force of the driving wheel and improving the acceleration performance. .
[0024]
On the other hand, as shown in FIG. 5, when the vehicle turns, the rear wheel's ground contact load tends to decrease and spin outward, but the rear wheel's ground load is compared to the normal time according to the current ground load of each wheel. As a result, the gripping force of each wheel is improved and the turning performance is improved. The illustrated one is a front-wheel drive vehicle, but the same applies to rear-wheel drive vehicles and four-wheel drive vehicles, although the degree is different.
[0025]
Here, each of the above figures describes the case of a general ground load distribution. However, when the load distribution changes, for example, when a relatively heavy object is loaded near the rear wheel of the front wheel drive vehicle, the load sensor It is good to detect this and to increase the ground contact load of each wheel according to the distribution.
[0026]
3, 4, and 5 conceptually show the tire ground contact load (= grip force) distribution, and the ground contact load in the static load range is indicated by a solid circle, which is increased by the stroke control of the actuator 5. The applied ground load is represented by a two-dot chain line circle.
[0027]
Generally, in order to save energy consumption of the actuator, a suspension spring that supports the vehicle weight and a damper for generating a damping force are used in combination (see FIG. 6).
When Ks is the spring constant of the suspension spring and C is the damping coefficient of the damper, the equations of motion for the sprung mass M2 and the unsprung mass M1 are given by the following equations, respectively.
M2 / Z2 ^** + C. (Z2 ^* -Z1 ^* ) + Ks. (Z2-Z1) =-Fz
M1 ・ Z1 ^** + C ・ (Z1 ^* −Z2 ^* ) + Ks ・ (Z1−Z2) + Kt ・ Z1 = Fz
[0028]
Therefore, the tire ground contact load W is given by the following equation.

[0029]
That is, it can be seen that the ground load W can be changed by controlling the expansion / contraction acceleration of the actuator, as described above.
[0030]
The actual vehicle inertia force is generated not only by the vertical motion but also by the rolling motion and the pitching motion. Here, the rotational motion around each axis passing through the center of gravity of the sprung mass,
Roll rate: φ
Pitch rate: θ
Yaw rate: γ
Lf, Lr, Tf / 2, and Tr / 2 are the distances from the center line in the front-rear direction and the center line in the left-right direction with respect to the center of gravity position to the center of contact of each wheel (see FIG. 7). If the thrust is Fz1 (front left), Fz2 (front right), Fz3 (rear right), Fz4 (rear left), and the direction of the force, moment, and coordinate system is shown in Fig. 8, the rolling moment Is
Mx = Tf / 2 · (−Fz1 + Fz2) −Tf / 2 · (−Fz3 + Fz4)
And the pitching moment is
My = Lf. (-Fz1-Fz2) -Lr. (-Fz3-Fz4)
It becomes.
[0031]
Also,
Rolling moment of inertia: Ix
Pitching moment of inertia: Iy
given that,
Rolling inertia is
Ixφ ^* = Mx
= Tf / 2. (-Fz1 + Fz2) -Tf / 2. (-Fz3 + Fz4)
And the pitching inertia is

It becomes.
[0032]
Furthermore, the inertial force of the vertical movement is
M2 ・ Z2 ^** = -Fz1-Fz2-Fz3-Fz4
Thus, by controlling at least one of these inertial forces, the grounding load when the rolling motion and the pitching motion are included is also individually controlled for each tire, so that the stability at a sudden acceleration is further improved. In addition, since a conventional thing distributes a load to four wheels, a rolling inertia force, a pitching inertia force, and an inertia force of a vertical motion do not occur, and these values are zero.
[0033]
In addition, since the operation | movement point of a traction control apparatus is well-known, the detailed description is abbreviate | omitted.
[0034]
Next, the idling prediction and detection processing by the drive wheel idling detection unit 27 will be described. First, signals from the wheel speed sensor 28, the vehicle speed sensor 29, the longitudinal acceleration sensor 30, the throttle opening sensor 31, the engine rotation speed sensor 32, the shift position sensor 33, the steering angle sensor 34, the yaw rate sensor 35, and the lateral acceleration sensor 36. Based on these data, the driving wheel idling detection unit 27 determines the state of the vehicle by comparing with a table of each data set in advance or by applying each data to a predetermined formula to predict idling of each wheel. Or whether it is already idle. If it is determined that the vehicle is idling or idling, the contact load to be increased in consideration of the road surface friction coefficient μ, that is, the biased contact load is calculated, and the contact load is actually increased by the above-described method. . Here, the road surface friction coefficient μ is preferably calculated from the detected values, the steering reaction force, and the like.
[0035]
In the above embodiment, a hydraulically driven cylinder device is used as the actuator. However, this may be achieved by using other electric thrust generating means such as a linear motor or a voice coil, a cam mechanism or a spring. Even if acceleration is generated using the means, the same effect can be obtained.
[0036]
In addition, the sensor used can be simplified without departing from the scope of the present invention. For example, the position detection signal can be obtained by second-order integration of the output difference of both the sprung and unsprung acceleration sensors, so that the stroke sensor can be eliminated, and the actual measured values of both the sprung and unsprung weights can be used. Since the force generated by the actuator can be obtained by calculating the output values of both the sprung and unsprung acceleration sensors, the load sensor can be eliminated. Further, a state estimator can be configured based on signals from the load sensor and the displacement sensor, and both the sprung and unsprung accelerations can be obtained indirectly. Furthermore, it goes without saying that the ECU can be realized in any of digital, analog, and hybrid.
[0037]
【The invention's effect】
As described above, according to the present invention, when idling of a wheel is predicted or detected during acceleration or turning, an inertial force in the vertical direction is generated in the vehicle body by the extension acceleration of the actuator provided between the vehicle body and the axle. By causing the reaction force to act on the contact surface, the contact load of the tire can be temporarily increased, the generation limit of the grip force of the tire can be increased, and the vehicle can be accelerated or turned stably and efficiently. Moreover, it can accelerate or turn more efficiently by combining this and the traction control device to cooperate. At this time, by using a common sensor and determination means for predicting or detecting the idling of the wheel, the structure is simplified and the number of parts is reduced.
[Brief description of the drawings]
FIG. 1 is a schematic system configuration diagram of an active suspension device to which the present invention is applied.
FIG. 2 is a model diagram for explaining the principle of the present invention.
FIG. 3A is a conceptual ground load distribution diagram at the start of a conventional front wheel drive vehicle, and FIG. 3B is a conceptual ground load distribution diagram at the start of a front wheel drive vehicle to which the present invention is applied.
4A is a conceptual grounding load distribution diagram at the start of a rear wheel drive vehicle to which the present invention is applied, and FIG. 4B is a conceptual view at the start of a four wheel drive vehicle to which the present invention is applied. Is a distribution diagram of ground contact load.
FIG. 5 is a conceptual ground load distribution diagram during turning of a front-wheel drive vehicle to which the present invention is applied.
FIG. 6 is a model diagram of a general active suspension system.
FIG. 7 is an explanatory diagram showing a relationship between a vehicle body center of gravity position and a ground contact position.
FIG. 8 is an explanatory diagram showing a relationship between force, moment, and direction of a coordinate system.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 Tire 2 Upper suspension arm 3 Lower suspension arm 4 Car body 5 Actuator 6 Piston 7 and 8 Oil chamber 9 Hydraulic pump 10 Servo valve 11 Piston rod 12 Accumulator 13 Unload valve 14 Oil filter 15 Check valve 16 Pressure adjustment valve 17 Oil cooler 18 Electronic control unit (ECU)
19 servo valve driver 20 load sensor 21 stroke sensor 22 sprung acceleration sensor 23 unsprung acceleration sensor 24 target load calculation unit 25 stabilization calculation unit 26 displacement limit comparison calculation unit 27 driving wheel idling prediction unit 28 wheel speed sensor 29 vehicle speed sensor 30 Longitudinal acceleration sensor 31 Throttle opening sensor 32 Engine rotation speed sensor 33 Shift position sensor 34 Steering angle sensor 35 Yaw rate sensor 36 Lateral acceleration sensor 37 Throttle opening control device

Claims (1)

An inertial force in the vertical direction is generated in the vehicle body by the extension acceleration of the actuator that actively changes the vertical relative distance between the vehicle body and the axle, and the reaction force is applied to the ground load acting between the tire and the road surface. A ground load control means, a wheel idling detection means for predicting and / or detecting that one of the wheels is idling at the time of starting or running, and a driving force generated by the wheel as a tire. A vehicle control device having traction control means for controlling to be near a peak value determined by a slip ratio with a road surface,
When the wheel idling detection means predicts that the wheel is idling and / or detects that the wheel is idling, the ground load control means preferentially controls the wheel driving force by the traction control means. A vehicle control apparatus that performs control of increasing a ground contact load of a wheel .

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