JP6770466B2 - Suspension control device - Google Patents

Description

The present invention relates to a suspension control device.

When the lower spring member overcomes the unevenness of the road surface while the vehicle is running, the suspension spring expands and contracts, and the bearing force that the suspension spring supports the upper spring member fluctuates, so that the upper spring member vibrates. In order to suppress the vibration of the spring-loaded member, an actuator interposed between the unsprung member and the spring-loaded member in the vehicle is interposed, and the thrust exerted by this actuator is controlled to control the spring-loaded member. There is a suspension control device that suppresses vibration.

Such a suspension control device is known to perform skyhook control by detecting the vertical velocity of the spring member and suppressing the vibration of the spring member. In the sky hook control, the state in which the spring member is suspended from the air by a fictitious skyhook damper is simulated by controlling the thrust exerted by the actuator to suppress the vibration of the spring member (for example, Patent Document 1). reference).

In addition, the unevenness of the road surface in front of the vehicle on which the vehicle is traveling is sensed in advance, and predictive control is performed to predict the vibration generated in the sprung member when the unsprung member overcomes the unevenness on the road surface to improve the riding comfort. Suspension control devices for further improvement have been developed (see, for example, Patent Document 2). In predictive control, the vibration of the unsprung member that may occur from the unevenness of the road surface is detected in advance, and the thrust of the actuator is controlled so that the vibration of the unsprung member is not transmitted to the spring member to suppress the vibration of the unsprung member. To do.

Japanese Patent Application Laid-Open No. 7-117447 JP-A-7-315028

The suspension control device that performs skyhook control detects the speed of the sprung member and suppresses the vibration of the sprung member with the actuator, but causes the actuator to exert a thrust that suppresses this against the movement of the sprung member. .. Therefore, in the suspension control device that performs skyhook control, although the vibration of the spring member can be reduced, it is required to improve the vibration suppressing effect.

Further, in the suspension control device that performs predictive control, the vibration transmitted from the unsprung member to the spring upper member cannot be accurately predicted unless the detection accuracy of the unevenness of the road surface is good. Furthermore, there is a response delay from the actuator control command to the output. Therefore, in the suspension control device that performs predictive control, it may not be possible to cancel the vibration transmitted from the unsprung member to the spring upper member well, and it is required to improve the vibration suppressing effect.

Therefore, an object of the present invention is to provide a suspension control device capable of improving the vibration suppressing effect of the spring member.

In order to achieve the above object, the suspension control device of the present invention includes a controller for controlling an actuator interposed between the lower spring member and the upper spring member together with the suspension spring in the vehicle, and the controller is a spring. Based on the vibration information of the lower member, the spring constant of the suspension spring, and the response delay information to the control command of the actuator, a control command for canceling the transmission force transmitted from the lower member to the upper spring member is obtained. When the suspension control device is configured in this way, the transmission force transmitted from the unsprung member to the spring upper member can be canceled while compensating for the response delay of the actuator.

The suspension control device, when the actuator is first-order lag system, the spring constant of the suspension spring and K _S, a displacement of the unsprung member and X _2, the time constant of the transfer function to the output from the control command of the actuator Assuming that T is T and the gain is k, the control command may be obtained by calculating the following equation (1). By obtaining the control command in this way, it is possible to generate a control command suitable for the actuator with the primary delay.

さらに、サスペンション制御装置は、アクチュエータが二次遅れ系である場合、懸架ばねのばね定数をＫ_Ｓとし、ばね下部材の変位をＸ_２とし、アクチュエータの制御指令から出力までの伝達関数における固有角周波数をωとし、アクチュエータの制御指令から出力までの伝達関数における減衰率をζとすると、以下の式（２）を演算して制御指令を求めてもよい。このように制御指令を求めると、二次遅れのアクチュエータに適した制御指令を生成できる。

Furthermore, the suspension control device, when the actuator is a secondary delay system, the spring constant of the suspension spring and K _S, a displacement of the unsprung member and X _2, specific angle of the transfer function to the output from the control command of the actuator Assuming that the frequency is ω and the attenuation rate in the transfer function from the control command of the actuator to the output is ζ, the control command may be obtained by calculating the following equation (2). By obtaining the control command in this way, it is possible to generate a control command suitable for the actuator with the secondary delay.

また、サスペンション制御装置は、ばね上部材の振動を抑制するばね上スカイフック制御力を加味して制御指令を求めてもよい。このように制御指令を求めると、アクチュエータがばね下部材からばね上部材へ伝達する伝達力を打ち消すだけでなく、ばね上部材の振動を抑制するばね上スカイフック制御力をも発揮するので、車両における乗心地が向上する。

Further, the suspension control device may obtain a control command in consideration of the sprung skyhook control force that suppresses the vibration of the sprung member. When the control command is requested in this way, the actuator not only cancels the transmission force transmitted from the unsprung member to the sprung member, but also exerts the sprung skyhook control force that suppresses the vibration of the sprung member. Riding comfort is improved.

Then, the suspension control device may obtain a control command in consideration of the unsprung skyhook control force that suppresses the vibration of the unsprung member. When the control command is requested in this way, the actuator not only cancels the transmission force transmitted from the unsprung member to the unsprung member, but also exerts the unsprung skyhook control force that suppresses the vibration of the unsprung member. Riding comfort is improved.

According to the suspension control device of the present invention, the vibration suppressing effect of the spring member can be improved.

It is a figure which showed the suspension control device in one Embodiment. It is a control block diagram of the controller in the suspension control device of one modification of one Embodiment. It is a figure which shows the structure of the suspension control device of another modification in one Embodiment.

Hereinafter, the present invention will be described based on the embodiments shown in the figure. As shown in FIG. 1, the suspension control device C in one embodiment is an actuator A interposed between a wheel W which is an unsprung member of a vehicle V and a vehicle body B which is an upper spring member together with a suspension spring S. Is controlled to suppress the vibration of the vehicle body B.

Hereinafter, each part will be described in detail. As shown in FIG. 1, the vehicle V, which is a system, is a suspension spring S which is interposed between a wheel W having tire Ti on the outer circumference, a vehicle body B, and the wheel W and the vehicle body B to elastically support the vehicle body B. It is composed of and.

Vehicle V, the tire Ti and spring of spring constant K _t, the wheel W and the mass of the mass M _1, the suspension spring S and a spring of spring constant K _S, two mass two to the vehicle body B and the mass of the mass M ₂ It is a spring mass system with a degree of freedom, and can be represented by the model of the spring mass system shown in FIG. Further, the road surface displacement is X ₀ , the vertical displacement of the vehicle body B is X ₁ , the vertical displacement of the wheel W is X _2, and the upward direction is positive in FIG.

The suspension control device C includes a sensor 1 for detecting vibration information of the wheel W, which is an unsprung member, and a controller 2 for _obtaining a control command _{fa_ref} given to the actuator A.

Suspension control device C, in this example, in order to detect the vertical displacement X ₂ and velocity dX 2 _/ dt of the wheel W as the vibration information of the wheel W is unsprung member, the sensor 1 is an acceleration sensor ing. The sensor 1 detects the vertical acceleration d ² X ₂ / dt ² of the wheel W and inputs it to the controller 2.

The control unit 2, as shown in FIG. 1, a speed calculating section 21 for the acceleration ^d 2 _X 2 / dt ² that is input from the sensor 1 integrated to determine the vertical velocity _dX 2 / dt of the wheel W, the acceleration Displacement calculation unit 22 that obtains the vertical displacement X ₂ of the wheel W by integrating d ² X ₂ / dt ² in the second order, and the displacement X ₂ and velocity dX ₂ / dt as vibration information of the wheel W that is a spring-down member. It is provided with a control command calculation unit 23 that generates a control command _{fa_ref} based on the above and inputs the control command _{fa_ref} to the actuator A.

Thus, the controller 2 gives generates a control command _{f A_ref} provide the vertical displacement _{X 2} and velocity _dX 2 / dt of the wheel W to the actuator A to the actuator A. The control command _{fa_ref} is a command that instructs the actuator A in the direction of expansion and contraction and the magnitude of thrust.

The actuator A is interposed between the vehicle body B and the wheels W in parallel with the suspension spring S, and is, for example, a telescopic cylinder using hydraulic pressure or pneumatic pressure, an electric linear actuator, or the like. Has a source. Then, the actuator A exerts a thrust of the direction and magnitude according to the control command by inputting the control command _{fa_ref} to expand and contract, and _vibrates the vehicle body B and the wheels W in the vertical direction.

Then, as shown in FIG. 1, a road surface displacement and X _0, the vertical displacement of the wheel W and X _2, the vertical displacement of the vehicle body B and X _1, the thrust is the output of the actuator A f _a Assuming that the upward direction is positive, the equation of motion of the vehicle body B can be expressed as the following equation (3) from the vertical balance of the vehicle body B, which is a spring-up member.

また、ばね下部材である車輪Ｗの上下方向の釣り合いから車輪Ｗの運動方程式は、以下の式（４）のように示せる。

Further, the equation of motion of the wheel W can be expressed as the following equation (4) from the vertical balance of the wheel W which is an unsprung member.

さらに、アクチュエータＡを一次遅れ系とし、アクチュエータＡの制御指令ｆ_{ａ＿ｒｅｆ}から出力である推力ｆ_ａまでの応答遅れにおける時定数をＴとすると、アクチュエータＡの応答に関する微分方程式は、以下の式（５）のように示せる。

Additionally, the actuator A as a first-order lag system, when the time constant and T the response delay of the thrust to f _a is outputted from the control instruction f _{A_ref} actuator A, the differential equation for the response of the actuator A has the following formula (5 ) Can be shown.

式（３）を分解すると以下の式（６）となる。

The following equation (6) is obtained by decomposing the equation (3).

ここで、路面変位Ｘ_０の変動（外乱）によって車輪Ｗが振動するが、車輪Ｗの振動によって車体Ｂへ伝達される伝達力を打ち消せば、車体Ｂへ車輪Ｗの振動の伝達をキャンセルして絶縁できる。つまり、路面変位Ｘ_０の変動（外乱）によって動かされる車体Ｂの変位Ｘ_１と、アクチュエータＡが推力ｆ_ａを発揮して動かされる車体Ｂの変位Ｘ_１が全く逆の大きさになれば両者が相殺される。車輪Ｗの変位Ｘ_２によって車体Ｂに作用する伝達力は、車輪Ｗの変位Ｘ_２によって懸架ばねＳが伸縮して懸架ばねＳが発揮するばね力となるから、アクチュエータＡの推力ｆ_ａが車輪Ｗの変位によって懸架ばねＳが発揮するばね力Ｋ_ＳＸ_２の符号を反転した値に等しくなればよい。

Here, the wheel W vibrates due to the fluctuation (disturbance) of the road surface displacement X ₀ , but if the transmission force transmitted to the vehicle body B by the vibration of the wheel W is canceled, the transmission of the vibration of the wheel W to the vehicle body B is canceled. Can be insulated. Both words, the displacement X ₁ of the vehicle body B which is moved by the fluctuation of the road surface displacement X ₀ (the disturbance), if the magnitude of the displacement X ₁ is completely reverse the vehicle body B which the actuator A is moved by exerting a thrust f _a Is offset. Transmitting force acting on the vehicle body B by a displacement X ₂ of the wheel W, since the suspension spring S and the suspension spring S is stretching the displacement X ₂ of the wheel W is a spring force that exerts thrust f _a of the actuator A the wheel The spring force K _S X ₂ exerted by the suspension spring S due to the displacement of W may be equal to the inverted value of the sign.

In the formula (3), if K S and _(X 2 _{-X 1)} and a value related numeric opposite sign equal thrust f _a, as indicated that the acceleration does not occur in the vehicle body B I think. In other words, it seems like may be used as the thrust _{f a = -K S (X 2} -X 1). However, (X _2- X ₁ ) is the relative displacement between the vehicle body B and the wheels W, and the change in the relative displacement is also due to the change in the posture of the vehicle body B due to turning, braking or acceleration, or the change in the load on the vehicle body B. It is not possible to determine whether it is due to road surface displacement. For example, when reducing the suspension spring S sinks forward of the vehicle body B by pitching _and exert a thrust to f _a = -K actuator A as _{S (X} 2 -X _1), to facilitate the sinking of the vehicle body B It exerts thrust in the direction. When the vehicle body B floats, it promotes the lifting. As described above, in the control for feeding back the relative displacement between the vehicle body B and the wheels W, there is a mode in which the posture of the vehicle body B is not stable and the vibration of the vehicle body B oscillates. Accordingly, the spring force K _S · X ₂ thrust f _a of the actuator A is the suspension spring S is exerted by the displacement X ₂ of the wheel W as transmission force, so as to cancel the transmission power, and obtains a thrust f _a of the actuator A Just do it. Based on the above, the following equation (7) may be established.

他方、ラプラス演算子をｓとして、式（５）の制御指令とアクチュエータＡの推力の関係を伝達関数で表現すると、伝達関数は、以下の式（８）で表現される。

On the other hand, when the Laplace operator is s and the relationship between the control command of the equation (5) and the thrust of the actuator A is expressed by the transfer function, the transfer function is expressed by the following equation (8).

この式（８）を式（７）に代入すると、式（９）となる。なお、式（９）中で、ｋはゲインである。この式（９）は、アクチュエータＡの制御指令ｆ_{ａ＿ｒｅｆ}の入力から推力ｆ_ａを出力するまでの応答遅れが勘案された式となる。

Substituting this equation (8) into equation (7) yields equation (9). In equation (9), k is a gain. The equation (9) is composed of an input control command f _{A_ref} actuator A and expression response delay has been consideration of to the output of thrust f _a.

ラプラス演算子ｓが乗算される変数は微分されるので、式（９）を展開して整理すると、以下の式（１０）が得られる。

Since the variable to which the Laplace operator s is multiplied is differentiated, the following equation (10) can be obtained by expanding and rearranging equation (9).

式（１０）から理解できるように、変位Ｘ_２に対して位相が進む速度を利用してアクチュエータＡの応答遅れを補償できる制御指令ｆ_{ａ＿ｒｅｆ}を求める。この式（１０）において、アクチュエータＡの制御指令ｆ_{ａ＿ｒｅｆ}の入力から推力ｆ_ａを出力するまでの応答遅れについて、予め、実機において時定数Ｔとゲインｋに計測すれば足り、車輪Ｗの変位Ｘ_２と速度ｄＸ_２／ｄｔをセンサ１で検知する加速度ｄ^２Ｘ_２／ｄｔ^２から得られる。よって、制御指令演算部２３は、式（１０）を演算すれば制御指令ｆ_{ａ＿ｒｅｆ}を求め得る。このように制御指令ｆ_{ａ＿ｒｅｆ}を求めてアクチュエータＡへ入力するとアクチュエータＡは、推力ｆ_ａを発揮して車輪Ｗからの伝達力を打ち消せるので、路面からの外乱入力による車体Ｂの振動を相殺して、車体Ｂの振動を抑制できる。

As can be seen from equation (10), by utilizing the speed at which the phase is advanced relative to the displacement X ₂ obtains a control command f _{A_ref} capable of compensating the response delay of the actuator A. In this formula (10), the response delay from the input of the control instruction f _{A_ref} actuator A to the output of thrust f _a, in advance, sufficient by measuring the constant T and the gain k when the actual displacement of the wheel W X _It is obtained from the acceleration d ² X ₂ / dt ² that detects ₂ and the velocity dX ₂ / dt with the sensor 1. Therefore, the control command calculation unit 23 can obtain the control command _{fa_ref} by calculating the equation (10). When the control command _{fa_ref} is obtained and input to the actuator A in this way, the actuator A exerts _a thrust _fa to cancel the transmission force from the wheel W, so that the vibration of the vehicle body B due to the disturbance input from the road surface is offset. Therefore, the vibration of the vehicle body B can be suppressed.

From the above, according to the suspension control device C of the present invention, the influence of the disturbance can be canceled while compensating for the response delay of the actuator A by a simple calculation process, so that the vehicle body B due to the change of the road surface displacement X ₀ which is the disturbance input The vibration can be effectively offset, and the vibration suppression effect of the vehicle body B can be improved.

Although possible to suppress the vibration of the vehicle body B even when the the _-K S _{X 2} obtained by inverting the sign of the displacement _{X 2} of the wheel W is multiplied by the spring constant _{K S} of the suspension spring S as the control command _{f A_ref,} actuator Since the response delay of A cannot be compensated, the vibration suppression effect is inferior. On the other hand, according to the suspension control device C of the present invention, since the control force for canceling the influence of the disturbance is obtained while compensating for the response delay of the actuator A, the vibration suppressing effect of the vehicle body B is improved.

In the case where the actuator A is provided with a characteristic of the secondary delay, the natural angular frequency and omega, when the attenuation factor zeta, when the gain and k, the transfer function from the control command f _{A_ref} to thrust f _a Is expressed as the following equation (11).

この式（１１）を式（７）に代入すると、式（１２）となる。式（１２）は、アクチュエータＡの制御指令ｆ_{ａ＿ｒｅｆ}の入力から推力ｆ_ａを出力するまでの二次の応答遅れが勘案された式となる。

Substituting this equation (11) into equation (7) yields equation (12). Equation (12) is a second-order response delay from the input of the control instruction f _{A_ref} actuator A to the output of thrust f _a is consideration equation.

ラプラス演算子ｓが乗算される変数は微分され、ラプラス演算子ｓの二乗が乗算される変数は二階微分となるので、式（１２）を展開して整理すると、以下の式（１３）が得られる。

The variable to which the Laplace operator s is multiplied is differentiated, and the variable to which the square of the Laplace operator s is multiplied is the second derivative. Therefore, when the equation (12) is expanded and arranged, the following equation (13) is obtained. Be done.

式（１３）から理解できるように、アクチュエータＡが二次の応答遅れ位の特性を備えている場合、一次遅れのアクチュエータＡに比較して、変位Ｘ_２から位相が進んだ速度ｄＸ_２／ｄｔに加えて、更に位相が進んだ加速度ｄ^２Ｘ_２／ｄｔ^２を加味して、制御指令ｆ_{ａ＿ｒｅｆ}を求めればよい。つまり、二次遅れのアクチュエータＡの場合、制御指令ｆ_{ａ＿ｒｅｆ}を求めるために利用するばね下部材である車輪Ｗの振動情報は、変位Ｘ_２、速度ｄＸ_２／ｄｔおよび加速度ｄ^２Ｘ_２／ｄｔ^２となる。このようにすれば、アクチュエータＡの応答遅れを補償しつつ、路面からの外乱入力による車体Ｂの振動を相殺して、車体Ｂの振動を抑制できる。よって、アクチュエータＡが高次の応答遅れとなれば、車輪Ｗの変位Ｘ_２から位相が次数分進んだ情報を加味すれば、アクチュエータＡの応答遅れの特性に対応して車体Ｂの振動を抑制できる。よって、制御指令ｆ_{ａ＿ｒｅｆ}を得るためのばね下部材である車輪Ｗの振動情報は、アクチュエータＡの応答遅れの次数に応じて、前述のように決定すればよい。

As can be understood from the equation (13), when the actuator A is provided with a characteristic of the secondary response delay position, first order lag as compared to the actuator A, the velocity dX 2 _/ dt of the displacement X ₂ advances the phase In addition to this, the control command _{fa_ref} may be obtained by adding the acceleration d ² X ₂ / dt ² whose phase is further advanced. That is, in the case of the actuator A having a secondary delay, the vibration information of the wheel W, which is an unsprung member used to obtain the control command _{fa_ref} , is displacement X ₂ , velocity dX ₂ / dt, and acceleration d ² X ₂ / dt. It becomes ² . In this way, the vibration of the vehicle body B can be suppressed by canceling the vibration of the vehicle body B due to the disturbance input from the road surface while compensating for the response delay of the actuator A. Therefore, if the actuator A is a higher order response delay, if considering the information phase advances a few minutes following the displacement X ₂ of the wheel W, suppressing the vibration of the vehicle body B so as to correspond to the characteristics of the response delay of the actuator A it can. Therefore, the vibration information of the wheel W, which is the unsprung member for obtaining the control command _{fa_ref} , may be determined as described above according to the order of the response delay of the actuator A.

As can be understood from the above, in the suspension control device C of the present invention, the road surface displacement is regarded as a disturbance, and the force (transmission force) transmitted to the vehicle body B in the vehicle V, which is a system, is canceled by the input of the disturbance. Is running. Therefore, when the actuator A is controlled only by the control, the actuator A cannot exert a damping force for damping the vibration when the vehicle body B vibrates. Therefore, in consideration of the case where the vehicle body B vibrates without completely canceling the transmission force due to the disturbance input, it is preferable to use the sky hook control for suppressing the vibration of the vehicle body B together with the control.

To perform skyhook control, the vehicle body speed dX ₁ / dt in the vertical direction of the vehicle body B is detected, the spring skyhook control force F _bsky is obtained from the vehicle body speed dX ₁ / dt, and the spring skyhook control is performed. The thrust f _{a of the} actuator A may be obtained by adding the force F _bsky to the force −K _s X ₂ that cancels the transmission force due to the displacement X ₂ of the wheel W. In order to detect the vehicle body speed dX ₁ / dt, as shown in FIG. 2, the vehicle body B is provided with an acceleration sensor 3 for detecting the vertical acceleration of the vehicle body B, and the controller 2 is provided with the acceleration detected by the acceleration sensor 3. The vehicle speed calculation unit 24 may be provided to integrate and obtain the vehicle body speed dX ₁ / dt. Further, the control command calculation unit 23 multiplies the vehicle body speed dX ₁ / dt by the sprung skyhook damping coefficient C _bsky to obtain the sprung skyhook control force F _bsky (F _bsky = C _bsky dX ₁ / dt), and _obtains the spring. by adding the force _-K s _{X 2} for canceling the transmission force due to the displacement _{X 2} of the upper skyhook control force _{F Bsky} and the wheel W, it may be determined thrust _{f a} of the actuator a. In this manner, when the thrust f _a determined to expand it into the equation (8), equation (14) below is obtained.

式（１４）を用いて制御指令ｆ_{ａ＿ｒｅｆ}を求めれば、アクチュエータＡは、伝達力を打ち消す力に加えてばね上スカイフック制御力Ｆ_ｂｓｋｙも発揮するので、車体Ｂが振動しても車体Ｂが制振されて車両における乗心地が向上する。

If the control command _{fa_ref} is obtained using the equation (14), the actuator A exerts the _sprung skyhook control force F _bsky in addition to the force that cancels the transmission force, so that the vehicle body B vibrates even if the vehicle body B vibrates. Vibration control improves the riding comfort in the vehicle.

The skyhook control may be applied to the vibration damping of the wheel W which is an unsprung member. In this case, the unsprung skyhook damping coefficient C _wsky is multiplied by the vertical velocity dX ₂ / dt of the wheel W to obtain the unsprung skyhook control force F _wsky (F _wsky = C _wsky dX ₂ / dt). adds to the force _-K s _{X 2} for canceling the transmission force due to the displacement _{X 2} of the wheel W, may be determined thrust _{f a} of the actuator a. In this manner, when the thrust f _a determined to expand it into the equation (8), equation (15) below is obtained.

式（１５）を用いて制御指令ｆ_{ａ＿ｒｅｆ}を求めれば、アクチュエータＡは、伝達力を打ち消す力に加えてばね下スカイフック制御力Ｆ_ｗｓｋｙも発揮するので、車輪Ｗの振動を抑制できるので、車体Ｂにおける振動も抑制されて車両における乗心地が向上する。なお、車輪Ｗの制振にスカイフック制御を利用する場合、図１に示したサスペンション制御装置Ｃの構成を変更せずに適用可能である。

If the control command _{fa_ref} is obtained using the equation (15), the actuator A exerts the _unsprung skyhook control force F _wsky in addition to the force that cancels the transmission force, so that the vibration of the wheel W can be suppressed. The vibration in B is also suppressed, and the riding comfort in the vehicle is improved. When sky hook control is used for damping the wheel W, it can be applied without changing the configuration of the suspension control device C shown in FIG.

When applying skyhook control to the vibration control of both the vehicle body B and the wheel W, the control command is added by adding the third and fourth terms on the right side of the equation (15) to the right side of the equation (14). You just have to ask.

Further, as shown in FIG. 3, if the dynamic damper D that suppresses the vibration of the wheel W is provided, the vibration of the wheel W can also be suppressed. The dynamic damper D is composed of a spring 4 on the wheel W and a weight 5 elastically supported by the spring 4. The dynamic damper D includes the spring 4 and the weight 5 at the specific frequency of the wheel W elastically supported by the tire Ti and the suspension spring S. The natural frequencies of the spring mass system consisting of are matched. In this way, if the natural frequency of the wheel W is matched with the natural frequency of the dynamic damper D, the vibration of the wheel W can be suppressed. If the dynamic damper D is used in combination with the control for canceling the transmission force in this way, even if the wheel W vibrates, this vibration can be reduced and the vibration of the vehicle body B can be effectively suppressed. Further, the dynamic damper D may be one that utilizes rotational inertia as long as the vibration of the wheel W can be suppressed. Further, as shown by the broken line in FIG. 3, the dynamic damper D may be configured by arranging dampers 6 that exert a damping force between the weight 5 and the wheels W in parallel. When the damper 6 is provided, even if the natural frequency of the wheel W and the natural frequency of the dynamic damper D deviate from each other, the vibration suppression cannot be performed at all, and there is an advantage that the vibration of the wheel W can be suppressed to some extent. Further, in controlling the vibration of the wheel W, a wheel with a built-in suspension as disclosed in JP-A-2003-191702, JP-A-2003-191703, or JP-A-2003-200702 may be used. Since the dynamic damper D and the wheel with a built-in suspension do not interfere with the skyhook control, both may be used together with the control for canceling the transmission force.

Although the preferred embodiments of the present invention have been described in detail above, modifications, modifications, and changes can be made without departing from the scope of claims.

A ... Actuator, B ... Body (spring member), C ... Suspension control device, S ... Suspension spring, V ... Vehicle, W ... Wheel (unsprung member), 2・ ・ ・ Controller

Claims (5)

A controller for controlling an actuator interposed between the unsprung member and the sprung member in the vehicle together with the suspension spring is provided.
The controller transmits vibration information transmitted from the unsprung member to the sprung member based on vibration information of the unsprung member, spring constant of the suspension spring, and response delay information to a control command of the actuator. A suspension control device characterized in that a control command for canceling a force is sought. Wherein the controller, if the actuator is a first-order lag system, the spring constant of the suspension spring and K _S, a displacement of the unsprung member and X _2, the time in the transfer function to the output from the control command for the actuator The suspension control device according to claim 1, wherein when the constant is T and the gain is k, the following equation (16) is calculated to obtain the control command.

Wherein the controller, if the actuator is a two-order lag system, in the spring constant of the suspension spring and K _S, a displacement of the unsprung member and X _2, the transfer function to the output from the control command for the actuator Claim 1 is characterized in that the control command is obtained by calculating the following equation (17), where ω is the natural angle frequency and the attenuation rate in the transfer function from the control command to the output of the actuator is ζ. The suspension control device described.

The controller obtains a spring-up skyhook control force that suppresses vibration of the spring-up member based on sky-hook control, and receives vibration information of the spring-down member, a spring constant of the suspension spring, and a control command of the actuator. The suspension control device according to any one of claims 1 to 3, wherein the control command is obtained based on the response delay information and the spring-loaded skyhook control force. The controller obtains an unspring skyhook control force that suppresses vibration of the unspring member based on skyhook control, and receives vibration information of the unspring member, a spring constant of the suspension spring, and a control command of the actuator. The suspension control device according to any one of claims 1 to 4, wherein the control command is obtained based on the response delay information and the spring-loaded skyhook control force.

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