JP2009520634A - Rolling prevention device for vehicle - Google Patents

Abstract

  From at least one actuator (21) capable of acting on a load change (roll) in which the turning body tilts outward, the lateral acceleration of the vehicle, the roll angle of the anti-roll torque applied to the vehicle, and the driving situation data, An apparatus (11) for controlling roll of a vehicle (1), comprising a module for predicting a roll state and a module for generating an asymptotic removal setting value of disturbance acting on the roll.

Description

  The present invention belongs to the field of control systems for ground vehicles, particularly wheeled motor vehicles. Conventionally, an automatic vehicle includes wheels connected to a vehicle body by a vehicle body, a passenger compartment, and a suspension mechanism, and a front wheel that is a steered wheel that is operated by a handle that is entrusted to a driver's operation in the passenger compartment. , Having a rear wheel that is a steering wheel or is not a steering wheel.

  Document US 2004/0117085 describes a yaw stability control unit capable of controlling an active suspension system and an active anti-roll bar system, a roll stability control unit and a lateral acceleration providing information to a priority determination and integration unit. A vehicle yawing control system is described that includes a sensor, a roll sensor, a steering angle sensor, and at least one speed sensor.

  Document US 2004/0117071 describes a vehicle roll limiting method comprising proportional, derivative and second derivative type corrections and a control signal sent to a brake control system or to a steering control system. Is described.

  However, these systems require a large number of sensors and cause the vehicle to be not sufficiently stable when subjected to certain actions from the driver or against certain road conditions. . Certain situations, such as avoiding single or double obstacles, can lead to vehicle out of control. The uncontrollability in this case is often due to maladaptation because the vehicle response is extreme, not sufficiently mitigated, or difficult to predict.

  An object of the present invention is a roll prevention control system that ensures safety, security, comfort, and great driving pleasure.

  A roll control method for a vehicle including at least one actuator capable of acting on roll (roll) is based on a lateral acceleration of the vehicle, a roll angle of an anti-roll torque applied to the vehicle, and a driving state data. Predicting and generating asymptotic removal setpoints for disturbances acting on the roll. Thereby, disturbance can be removed efficiently.

  Preferably, the roll state is predicted according to the set value of the actuator and the lateral acceleration. Preferably, the roll state is predicted according to the dynamic range of the actuator. Preferably, the change in the roll state is calculated according to the disturbance.

  In one embodiment, a roll angle is measured with a sensor, and a roll state is predicted from the measured roll angle. In one embodiment, the set value is generated according to the speed of the vehicle, the steering angle of the front wheels, and / or the braking pressure.

  A roll control apparatus for a vehicle includes: at least one actuator capable of acting on a roll; a module for predicting a roll state from a lateral acceleration of the vehicle, a roll angle of an anti-roll torque applied to the vehicle, and driving situation data; A module for generating asymptotic removal setpoints for disturbances acting on

  In one embodiment, each module is arranged in a closed loop configuration. In one embodiment, the actuator is coupled to a controllable anti-roll bar. In one embodiment, the actuator is coupled to the active suspension.

  The vehicle includes a vehicle body, at least three wheels coupled to the vehicle body, and a vehicle roll control device. The device includes at least one actuator capable of acting on a roll, a module that predicts a roll state from a lateral acceleration of the vehicle, a roll angle of an anti-roll torque applied to the vehicle, and driving situation data, and the roll. A module for generating an asymptotic removal setting value of the disturbance to be transmitted.

  The present invention is applied to a vehicle having four wheels, two wheels, three wheels, or a vehicle having six or more wheels, at least two of which are steering wheels. Is done. The present invention enables a vehicle to take a desired roll behavior regardless of the driver's approach or road surface condition, and thereby enhances the comfort of a user of an automatic vehicle, among others. it can. Further, the present invention can enhance the sense of security, comfort and driving pleasure.

  The active anti-roll system can minimize the lateral response of the vehicle to steering by the driver while taking into account the vehicle speed. Optimization is performed according to the respective standards of safety, comfort and driving enjoyment.

  The invention will be better understood by considering the detailed description of several embodiments, illustrated by way of non-limiting example, and illustrated by the accompanying drawings, in which:

  As can be seen from FIG. 1, the vehicle 1 includes a vehicle body 2, two steering front wheels 3 and 4, and two rear wheels 5 and 6. Each wheel is connected to the vehicle body 2 by a suspension mechanism (not shown). Yes.

  The vehicle 1 includes a rack 8 arranged between the front wheels 3 and 4 and a rack 8 in response to a command received mechanically or electrically from a steering handle (not shown) entrusted to the operation of the driver of the vehicle. It is realized with a steering system 7 comprising a rack actuator 9 which can orient the front wheels 3 and 4 via.

  The anti-roll system 10 includes a control unit 11, a vehicle wheel speed sensor 13 that can determine the vehicle speed V, and the vehicle roll angle θ, the vehicle's center of gravity around the longitudinal axis along the longitudinal axis. A tilt sensor 14 and, optionally, a steering position sensor 12 for the front wheels 3 and 4 disposed on the actuator 9 are provided as an option.

  Further, the system 10 can include steering angle sensors 17 and 18 for the rear wheels 5 and 6 and actuators 19 and 20 that can direct the rear wheels 5 and 6. However, only a single sensor 17 and a single actuator 19 are sufficient for detecting the steering angle and directing the rear wheels 5 and 6. This is because the rear wheels 5 and 6 are not steering wheels. The position sensor and the velocity sensor may be optical or magnetic fields using, for example, the Hall effect, and may cooperate with an encoder connected to the movable part, but the sensors do not rotate.

The vehicle 1 includes two anti-roll bars 15 and 16 that connect the front wheels 3 and 4 and the rear wheels 5 and 6, respectively. The anti-roll system 10 includes at least one actuator shown here. The two actuators 21 and 22 are linked to the front anti-roll bar 15 and the rear anti-roll bar 16, respectively, and when receiving a control command from the control unit 11, an active anti-roll bar acting on the bars 15 and 16. Form. The actuators 21 and 22 can change the rigidity of the anti-roll bars 15 and 16 according to a set value received from the control unit 11, for example. The system 10 may include a lateral acceleration γ _T sensor 23 and a brake circuit pressure P sensor 24.

  The control unit 11 receives information from the RAM, ROM, central processing unit and sensors and is realized in the form of a microprocessor with an input / output interface that can in particular direct the anti-roll actuators 21 and 22 Can do.

More specifically, the control unit 11 comprises an input block 24 for receiving signals from the sensors 13, 14 and 23, in particular the vehicle speed V, the roll angle θ and the lateral acceleration γ _T (see FIG. 2). The vehicle speed V can be obtained by averaging the speeds of the front or rear wheels measured by sensors of the wheel antilock system. In this case, one sensor 13 is prepared for each wheel, and the wheel antilock system has an output that is input to the control unit 11 to supply vehicle speed information. Or the value of each sensor 13 is input into the control unit 11, and the control unit 11 receives this, and obtains the average value of the speed of a wheel.

The control unit 11 comprises a state observer 25 that can predict information that is not measured but that is necessary for control, such as disturbances that act on the vehicle, among others. The input block 24 supplies the state observer 25 with data “situations” relating to the driving situation, such as the vehicle speed V, the roll angle θ, the lateral acceleration γ _T , and in particular the steering angle α ₁ and / or the pressure P. For example, the state observer 25 is derived from a model based on a simple equation expressing transmission between the lateral acceleration γ _T and the roll angle θ of the vehicle body and between the torque μ _f applied by the anti-roll actuator and the roll angle θ of the vehicle body. Can be built. This equation can be written as follows, for example.

このモデルに付随する状態方程式は、次のようになる。

式中の記号はそれぞれ以下のとおりである。

By addition actuators, as distinguished from the actual Added torque mu _f control torque mu _c, it can be introduced the dynamic range of the actuator. This can be expressed as:

The equation of state associated with this model is:

The symbols in the formula are as follows.

は車体のロール速度であり、

はモデルによって計算した車体のロール速度であり、μ_ｃはロールトルクの設定値、μ_ｆはアクチュエータのダイナミックレンジによるフィルタをかけた、すなわち実際に加えられるロールトルクであり、τ_ａはアンチロール・アクチュエータの応答時間である。 Where y is the output, M is the total weight of the vehicle, and I _xx is the inertia around the longitudinal axis where the car body is located above its roll axis, ie the ground surface, and can tilt slightly forward. L is the wheel base of the vehicle, h ₀ is the height of the center of gravity with respect to the roll axis of the vehicle body, E ₁ is the front wheel tread, E ₂ is the rear wheel tread, and α ₁ is the steering of the front wheel Is the roll angle of the vehicle body, θ _c is the roll angle of the vehicle body calculated by the model,

Is the body roll speed,

Is the roll speed of the vehicle body calculated by the model, μ _c is the set value of the roll torque, μ _f is the roll torque that is filtered by the dynamic range of the actuator, that is, actually applied, and τ _a is the anti-roll Actuator response time.

によって特徴づけられる外乱をステップ外乱としてモデル化することができる。すると、オブザーバの発展方程式は次のようになる。

これを、

および

と書く。ここで、＾は値が予測値であることを示す。 Next, based on the same model, an additional disturbance is added to the model to construct this observer. For example, the equation

The disturbance characterized by can be modeled as a step disturbance. Then, the observer's evolution equation is as follows.

this,

and

Write. Here, ^ indicates that the value is a predicted value.

It can be seen that the observer depends on the speed. It should also be noted that K _obs is an observer configuration parameter. K _obs can be calculated for various vehicle speeds, and by inserting this, K _obs (V) is obtained, and different behaviors depending on the vehicle speed are obtained.

は、制御ユニット１１の他の要素によって使用される、車両状態に関する予測値を供給する。制御ユニット１１は外乱の漸近的除去ブロック２６をさらに備える。このブロック２６は、外乱値

を、一般に車両１のロール角θとなる当該出力に比して無視できるものとすることができる。閉ループ化は、状態オブザーバ２５によって予測される外乱値

に対して行われる。 4 predicted values

Supplies a predicted value relating to the vehicle state, which is used by other elements of the control unit 11. The control unit 11 further comprises a disturbance asymptotic removal block 26. This block 26 shows the disturbance value

Can be neglected as compared with the output which is generally the roll angle θ of the vehicle 1. The closed loop is a disturbance value predicted by the state observer 25.

To be done.

すなわち、

第１の関係から、Ｔ_a,1＝１を得る。
第２の関係から、

を得る。

さらに、横方向加速度γ_Ｔはフィードバックされないため、Ｇ_a,2＝０である。この入力は制御できなく、そのまま維持されるためである。

その結果、以下を得る。

The calculation of asymptotic removal of disturbances is based on the method of Larminat (Automatique, Commande des systems lineaires-Philippede Larminat-Hermes). In order to achieve asymptotic removal of disturbances, the following two relations must be satisfied:

That is,

From the first relationship, T _{a, 1} = 1 is obtained.
From the second relationship,

Get.

Further, since the lateral acceleration γ _T is not fed back, G _{a, 2} = 0. This is because this input cannot be controlled and is maintained as it is.

As a result, the following is obtained.

となる。したがって、外乱除去のための制御は、

で表される。 Further, the gain of the state feedback is given by G = (G ₁ G _a + G ₁ T _a ). Since the disturbance d is simply removed without changing the system dynamic range, G ₁ = (000). Therefore, after all,

It becomes. Therefore, the control for disturbance removal is

It is represented by

Control unit 11, which forms the output of the overall control unit supplies a torque setpoint mu _c, completed with a output 27 for transmitting it to the anti-roll actuator 21 and 22.

In the embodiment shown in FIG. 3, the anti-roll system 10 is responsive to the lateral acceleration or front wheel steering angle as described in French Patent Application No. 0507113 simultaneously with the disturbance removal means as described above. Perform open loop control, setting the dynamic and static roll response of the vehicle. Therefore, the control unit 11, except that the torque set value mu _c is again looped back to input block 24, a state observer 25 which receives the same data as in the embodiment the input side, transverse to the input side A disturbance removal module 28 that receives the acceleration γ _T and the driving state data “situation” and outputs a control torque μ _ff on the output side is provided. The control unit 11 includes an adder 29 for inputting the control torque μ _ff and the removal set value “μ _removal ”, and adds the two values to output the torque set value μ _c to the output side.

アクチュエータのダイナミックレンジをモデル化することによって、アクチュエータによって実際に加えられるトルクの測定を回避することができる。すなわち、

ここで、μ_ｆは加えられるトルク、μ_ｃはトルク設定値、τ_ａはアクチュエータのダイナミックレンジ、ｓはラプラス演算子である。このモデルに付随する状態方程式は、次のとおりである。

モデル３０は、計算によるロール角θ_ｃ、計算によるロール速度

および、アクチュエータのダイナミックレンジによるフィルタをかけた、すなわち実際に加えられるロールトルクμ_ｆを供給する。 The disturbance rejection module can include a vehicle model 30 that is not measured but can predict information required for control (see FIG. 4). Model 30 may be predicted specific behavior of the vehicle body 2, i.e. the roll mode response of the vehicle body 2 in accordance with the lateral acceleration gamma _T of the vehicle. This model, for example, between the lateral acceleration gamma _T and the vehicle body roll angle θ and may as those based on simplified equations of transfer elements between the torque mu _f and the vehicle body roll angle θ exerted by the actuator. That is,

By modeling the dynamic range of the actuator, it is possible to avoid measuring the torque actually applied by the actuator. That is,

Here, μ _f is the applied torque, μ _c is the torque set value, τ _a is the dynamic range of the actuator, and s is the Laplace operator. The equation of state associated with this model is:

The model 30 has a calculated roll angle θ _c and a calculated roll speed.

Then, a roll torque μ _f that is filtered by the dynamic range of the actuator, that is, actually applied, is supplied.

ここで、速度Ｖにおける極の実数部をａ_１（Ｖ）、虚数部をｂ_１（Ｖ）と記している。その上で、ループ化されたシステムの極を以下に設定する補償ファクタ Ｋ＝［Ｋ_１（Ｖ） Ｋ_２（Ｖ） Ｋ_３（Ｖ）］が求められる。

ここで、Ｔｄｙｎ_１１、Ｔｄｙｎ_１２、Ｔｄｙｎ_２１、Ｔｄｙｎ_２２、Ｔｄｙｎ_３１、Ｔｄｙｎ_３２は、車両の過渡応答の設定パラメータ（車両の速度Ｖに依存する変数）である。 In addition, the control unit 11 includes a transient value calculation block 31 for inputting the above-described output of the model 30 and the speed V of the vehicle 1. Block 31 calculates the control by pole placement that allows it to affect the transient response. The three poles of the system described above are described as follows.

Here, the real part of the pole in the velocity V _a 1 (V), which shows information about imaginary part _b 1 and (V). Then, a compensation factor K = [K ₁ (V) K ₂ (V) K ₃ (V)] is set, which sets the poles of the looped system to:

Here, Tdyn ₁₁ , Tdyn ₁₂ , Tdyn ₂₁ , Tdyn ₂₂ , Tdyn ₃₁ , and Tdyn ₃₂ are setting parameters for the transient response of the vehicle (variables depending on the vehicle speed V).

The compensation factor K (V ₀ ) is calculated for the selected individual velocity V ₀ by the paper “Robust Pole” by J. Kautsky et NK Nichols published in Int. J. Control, 41 (1985), pages 1129-1155. It can be calculated by the pole setting method described in “Assignment in Linear State Feedback”.

設定パラメータが１のときは車両の動的応答は変更されず、１を超えるパラメータは車両のロール応答を増大させ、１未満のパラメータは車両のロール応答を低下させることがわかる。一例として、次のように設定することができる。
Ｔｄｙｎ_１１＝0.8
Ｔｄｙｎ_１２＝0
Ｔｄｙｎ_２１＝0.8
Ｔｄｙｎ_２２＝0
Ｔｄｙｎ_３１＝0.8
Ｔｄｙｎ_３２＝0 This gives the first part of the command as follows:

It can be seen that when the set parameter is 1, the dynamic response of the vehicle is not changed, a parameter greater than 1 increases the roll response of the vehicle, and a parameter less than 1 decreases the roll response of the vehicle. As an example, it can be set as follows.
Tdyn ₁₁ = 0.8
Tdyn ₁₂ = 0
Tdyn ₂₁ = 0.8
Tdyn ₂₂ = 0
Tdyn ₃₁ = 0.8
Tdyn ₃₂ = 0

With this setting, the dynamic response of the vehicle can be decelerated while suppressing roll vibration. This setting can increase the comfort of the passenger by reducing the sudden start of the roll that the passenger feels when entering the curve. Thus, block 31 provides the coefficients K ₁ , K ₂ and K ₃ and the first part of the command “μ _{c transient} ” to the output.

ここでＴｇｓは、必要であれば速度Ｖに応じて変化させることができる設定パラメータである。 In addition, the control unit 11 includes a block 32 for calculating a static command “μ _{c static} ” from which the coefficients K1, K ₂ and K ₃ , the vehicle speed V and the lateral acceleration γ _T are input. . This command “μc _static ” can set a static value of the roll angle of the vehicle body, which is generated in response to a steering operation of a predetermined size. This result can be expressed as follows in comparison with the static gain (right side) that can be obtained in the same vehicle without the active anti-roll device. That is,

Here, Tgs is a setting parameter that can be changed according to the speed V if necessary.

パラメータＴｇｓが１のとき、車両の静的応答は変更されず、パラメータＴｇｓが１を超えるときは車両の静的応答は強められ、パラメータＴｇｓが１未満のときは車両の静的応答は弱められることがわかる。一例としてＴｇｓを０．８とすることによって、安定した転回時に車体に生じるロールを減らし、それによって乗員の快適性を顕著に改善することができる。 The second part of the command is calculated according to the parameter Tgs as follows: That is,

When the parameter Tgs is 1, the vehicle's static response is not changed, when the parameter Tgs exceeds 1, the vehicle's static response is strengthened, and when the parameter Tgs is less than 1, the vehicle's static response is weakened. I understand that. As an example, by setting Tgs to 0.8, it is possible to reduce rolls generated in the vehicle body during stable turning, thereby significantly improving passenger comfort.

The control unit 11 is completed with an adder 33 and an output 34. The adder 33 inputs the control output “μ _{c transient} ” of the block 31 as one input data and the command output “μ _{c static} ” of the block 32 as another addition input data. On the other hand, the output of the adder 33 becomes output data of the disturbance removal module.

In the embodiment shown in FIG. 5, the steering angle α ₁ is filtered based on the calculated roll angle θ _c , the vehicle roll state X _2c, and the dynamic range of the actuator, and the roll torque μ _f that is actually applied is Used for calculation by the model 31.

アクチュエータによって実際に加えられるトルクμ_ｆは、前記と同様、測定したものではなく、同様にアクチュエータのダイナミックレンジをモデル化して得たものである。すなわち、

The control unit 11 shown in FIG. 5 is similar to that shown in FIG. 4 except that the model 30 is based on the following equation, for example. Here, α ₁ is the steering angle of the front wheels.

Indeed Added torque mu _f by the actuator is similar to the above, not measured, in which the dynamic range of the actuator obtained by similarly modeled. That is,

ただし、

であり、ｙは当該出力であり、Ｘ_2,cは

によって定義される、車両の第２のロール状態である。 The equation of state associated with this model is:

However,

, Y is the output, and X _{2, c} is

Is the second roll state of the vehicle as defined by

ただしＴｇｓは、必要であれば、速度Ｖに応じて変化することができる設定パラメータである。 The block 31 for calculating the transient value is the same as that shown in FIG. The static control calculation block 32 can set a stable value of the roll angle of the vehicle body, which is generated in response to a steering operation of a predetermined size. The result is expressed as follows compared to the static gain (right side) that can be obtained with the same vehicle without active anti-roll device. That is,

However, Tgs is a setting parameter that can be changed according to the speed V if necessary.

式中の記号は前述のとおりである。すなわち、

制御ユニット１１は前記実施形態と同様、ブロック３１の出力「μ_２過渡」と、ブロック３２からの出力「μ_２静的」とを入力する加算器３３をもって完結する。 The second part of the command is calculated according to the parameter Tgs as follows:

The symbols in the formula are as described above. That is,

The control unit 11 is completed with an adder 33 that inputs the output “μ _{2 transient} ” of the block 31 and the output “μ _{2 static} ” from the block 32, as in the above embodiment.

  The present invention provides a control method capable of controlling an active anti-roll system and setting a dynamic and static roll response of a vehicle according to a lateral acceleration or a front wheel steering angle by an open loop strategy. provide. This control can depend on the speed V of the vehicle, for example. The vehicle is designed for the most stable behavior regardless of the driver's demands and road conditions, providing an extremely high level of safety, security, comfort and driving enjoyment in an optimized state .

  The invention makes it possible to benefit from changes in the operation of the anti-roll bars 15 and 16 when the vehicle desires, especially as soon as the vehicle enters the curve, so that the grounding of the vehicle and the driving feel felt by the driver. Improve comfort.

1 is a schematic diagram of a vehicle equipped with a control system according to one aspect of the present invention. 1 is a logic diagram of a system according to one aspect of the present invention. FIG. 3 is a logic diagram of a system according to another aspect of the invention. FIG. 3 is a block diagram of a control unit 11 according to another aspect of the present invention. FIG. 3 is a block diagram of a control unit 11 according to another aspect of the present invention.

Claims (11)

  A roll control method for a vehicle (1) comprising at least one actuator (21) capable of acting on roll (roll), the vehicle lateral acceleration, the roll angle of anti-roll torque applied to the vehicle and driving A method of predicting a roll state from situation data and generating an asymptotic removal setting value of disturbance acting on the roll   The method according to claim 1, wherein a roll angle is predicted according to a set value and a lateral acceleration of the actuator.   The method according to claim 2, wherein a roll angle is calculated according to a dynamic range of the actuator.   The method according to claim 1, wherein the change of the roll angle is calculated according to the disturbance.   The method according to claim 1, wherein the change of the roll angle is measured according to the value of the sensor.   The device according to any one of claims 1 to 5, wherein the set value is generated according to a vehicle speed, a steering angle of a front wheel, and / or a braking pressure.   At least one actuator (21) capable of acting on roll (roll), and a module (24) for predicting the roll state from the lateral acceleration of the vehicle, the roll angle of the anti-roll torque applied to the vehicle and the driving situation data And a roll control device (11) for a vehicle, comprising: a module (25) for generating an asymptotic removal setting value for disturbance acting on the roll.   The apparatus of claim 7, wherein each module is arranged in a closed loop configuration.   9. An apparatus according to claim 7 or 8, wherein the actuator is connected to a controllable anti-roll bar.   The apparatus of claim 7 or 8, wherein the actuator is coupled to an active suspension.   A vehicle comprising a vehicle body, at least three wheels coupled to the vehicle body, and a vehicle roll control device (11), wherein the device can act on the roll; A module (24) for predicting the roll state from the lateral acceleration of the vehicle, the roll angle of the anti-roll torque applied to the vehicle and the driving situation data, and a module (25) for generating asymptotic removal setting values of disturbance acting on the roll A vehicle comprising:

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