JP2018134899A - Suspension device and control apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a control apparatus that can inexpensively remove a vibrational component of outputs from a plant due to disturbance.SOLUTION: A suspension device according to the present invention includes wheels W each having a tire T and configured to travel on a road surface R, a vehicle body B, and a controller 2 configured to control an actuator A capable of controlling vibration of the vehicle body B in a system V that includes a suspension spring S interposed between the wheel W and the vehicle body B. The suspension device generates a control command on the basis of a transfer function Gr from a displacement Xof the road surface R to a displacement Xof the vehicle body B, a transfer function Gu from a control command Ufor the actuator A to the displacement Xof the vehicle body B, and the displacement information of the road surface R.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a suspension device and a control device.

  When the vehicle travels over the road surface unevenness while the vehicle is running, the suspension spring expands and contracts, and the support force by which the suspension spring supports the vehicle body fluctuates, causing the vehicle body to vibrate. In order to suppress the vehicle body vibration, a suspension device that suppresses the vibration of the vehicle body using a damping force variable damper or an actuator may be used in the vehicle.

  In such a suspension device, vibrations of the vehicle body are suppressed by controlling a load (control force) exerted by an actuator or a damping force variable damper interposed between the vehicle body and the wheel. How to obtain the control force varies depending on the control law, but in general, vibration control of the vehicle body is obtained from vibration information of the vehicle body.

  This suspension device can effectively suppress body vibration compared to the case where only passive dampers are used. However, since the actuator etc. exerts the control force after grasping the vibration state of the vehicle body, the generation of control force There is a case where it is difficult to suppress the vehicle body vibration due to a time delay. Therefore, a suspension device has been developed that senses road surface unevenness in advance and performs predictive control for predicting vibrations that occur in the vehicle body when the wheel gets over the road surface unevenness to further improve riding comfort ( For example, see Patent Document 1).

Japanese Patent Laid-Open No. 7-315028

  In the suspension device that performs such a predictive control, the vehicle body vibration can be predicted by sensing the road surface displacement with the preview sensor, so that it is possible to control the vehicle body vibration predicted by the control force generated by the actuator or the like.

  However, in order to calculate the control force that should be exerted by the actuator or the like, a complicated calculation such as calculating the transmission force estimated to be applied to the vehicle body from the road surface input and obtaining the control force that cancels the transmission force is required.

  Accordingly, an object of the present invention is to provide a suspension device and a control device capable of generating a control command that cancels the influence of disturbance by simple arithmetic processing.

  In order to achieve the above-described object, the suspension device of the present invention is configured such that the controller has a transfer function from the road surface displacement to the vehicle body displacement, velocity or acceleration and a transfer function from the control command to the actuator to the vehicle body displacement, velocity or acceleration. And a control command for canceling the influence of the disturbance based on the road surface displacement information. Therefore, in the suspension device of the present invention, it is possible to cancel the vibration of the vehicle body by canceling the vibration of the vehicle body due to road surface input.

  In addition, when the suspension device also uses skyhook control, even if the vehicle body vibrates, it is possible to effectively suppress the vibration of the vehicle body by attenuating this vibration.

  Further, when the suspension device includes a dynamic damper that suppresses the vibration of the wheel, even if the wheel vibrates, the vibration can be reduced and the vibration of the vehicle body can be effectively suppressed.

  The control device includes a controller that controls a control target that can control the output in the system in which the influence of the disturbance is output with a time delay with respect to the input of the disturbance, and from the input of the disturbance to the output of the system. A control command for canceling the influence of the disturbance from the output may be generated based on the transfer function and the transfer function from the control command for the controlled object that controls the output of the system to the output and the disturbance information input to the system. In the control device configured as described above, the influence of disturbance can be canceled from the output.

  According to the suspension device or the control device of the present invention, it is possible to generate a control command that cancels the influence of disturbance by a simple arithmetic process.

1 is a model diagram of a vehicle to which a suspension device according to an embodiment is applied. It is a control block diagram of the controller in the suspension device in one embodiment. It is a control block diagram of the controller in the suspension device of the modification of one embodiment. FIG. 10 is a model diagram of a vehicle to which a suspension device according to another modified example of the embodiment is applied. It is a model figure of the structure to which the damping device was applied.

  The present invention will be described below based on the embodiments shown in the drawings. As shown in FIGS. 1 and 2, the control device in one embodiment is applied to a suspension device C for damping a vehicle body B.

In applying the control device to the suspension device C, the disturbance is the road surface displacement X ₀ , the system is the vehicle V, the output is the displacement X _{2 of the} vehicle body B, and the controlled object whose output can be controlled is the actuator A.

  Hereinafter, each part will be described in detail. As shown in FIG. 1, a vehicle V as a system includes a wheel W having a tire T, a vehicle body B, and a suspension spring S that is interposed between the wheel W and the vehicle body B and elastically supports the vehicle body B. It is configured.

Vehicle V, the tire T and the spring of spring constant K _1, and the wheel W and the mass of the mass M _1, the suspension spring S and a spring of spring constant K _2, two mass two to the vehicle body B and the mass of the mass M ₂ This is a spring mass system having a degree of freedom, and can be expressed by a model of the spring mass system shown in FIG.

The suspension device C includes a sensor 1 for sensing a road surface displacement (vertical displacement of the road surface) X ₀ to advance the wheel W passes future as the displacement information of the road surface R. The sensor 1 includes, for example, a distance sensor that detects the distance from the road surface R and an acceleration sensor that detects the vertical acceleration of the vehicle body B. The sensor 1 is obtained from the distance between the road surface R and the vehicle body B and the output of the acceleration sensor. detecting a road surface displacement X ₀ based on the vertical displacement of the vehicle body B was. The configuration of the sensor 1 is not limited to the above. Also, advance the road surface displacement X ₀ when knows Suspension device C side can omit the sensor 1.

Furthermore, the suspension apparatus C includes a controller 2 that generates a control command U ₀ and an actuator A that is interposed between the wheel W and the vehicle body B as a control target controlled by the controller 2. As shown in FIG. 2, the controller 2 generates a control command U ₀ to be given to the actuator A in response to the input of the road surface displacement X ₀ , and the actuator A expands and contracts in response to the input of the control command U _{0 in} the vertical direction. Can be excited. As the actuator A, for example, a telescopic cylinder using hydraulic pressure or pneumatic pressure, an electric linear actuator, or the like can be used.

In this example, since the output of the system is the vibration of the vehicle body B, the controller 2 generates a control command U ₀ that instructs the actuator A on the thrust and the expansion / contraction direction from the road surface displacement X ₀ detected by the sensor 1. In the case the displacement information of the road surface R is known, the control unit 2, by referring to said displacement information and the traveling point information of the vehicle V, it may be grasp the current road surface displacement X ₀ of the wheel W.

Then, as shown in FIG. 1, a road surface displacement and X _0, the vertical displacement of the wheel W and X _1, the vertical displacement of the vehicle body B and X _2, consider an upward displacement as positive, the road surface displacement the transfer function from X ₀ to the displacement _{X 2} of the vehicle body B is defined in formula (1) below Gr.

次に、制御指令をＵ_０とし、車体Ｂの上下方向の変位をＸ_２とし、上向きの変位を正として考え、制御指令Ｕ_０から車体Ｂの変位Ｘ_２までの伝達関数をＧｕを以下の式（２）で定義する。

Next, assume that the control command is U ₀ , the vertical displacement of the vehicle body B is X ₂ , the upward displacement is positive, and the transfer function from the control command U ₀ to the displacement X _{2 of the} vehicle body B is expressed as follows: It defines with Formula (2).

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_２と、制御指令Ｕ_０によりアクチュエータＡが伸縮して動かされる車体Ｂの変位Ｘ_２が全く逆の大きさになれば両者が相殺される。よって、車体Ｂを動かさないようにさせるには、以下の式（３）が成り立てばよい。

The displacement X ₂ of the vehicle body B which is moved by the fluctuation of the road surface displacement X ₀ (the disturbance), both if the magnitude of the displacement X ₂ is completely reverse the vehicle body B which the actuator A is moved by expansion and contraction in response to the control instruction U ₀ Offset. Therefore, in order to prevent the vehicle body B from moving, the following equation (3) may be established.

この式（３）を変形して、制御指令Ｕ_０について解くと以下の式（４）となる。伝達関数Ｇｒと伝達関数Ｇｕは、車両（システム）Ｖのモデルから一義的に求まり既知であるから、式（４）中の右辺で路面変位Ｘ_０が検出できれば、制御指令Ｕ_０を求め得る。

When this equation (3) is modified and solved for the control command U ₀ , the following equation (4) is obtained. The transfer function Gu and the transfer function Gr is because it is known values are found uniquely from the model of the vehicle (system) V, if detected road surface displacement X ₀ in the right-hand side in the formula (4) can determine the control command U _0.

路面変位Ｘ_０は、センサ１で検知できるので、本発明のサスペンション装置（制御装置）Ｃは、わざわざ、車体Ｂへの伝達力を求めるといった複雑な演算を要せずに路面変位Ｘ_０から直接に制御指令Ｕ_０を求め得るのである。外乱の入力から外乱の影響が出力に現れるまでに時間遅れがあるシステムでは、このように制御指令Ｕ_０を生成してアクチュエータＡを制御すれば、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。

Road displacement X _0, since detectable by the sensor 1, the suspension device (control device) C of the present invention, bother, directly from the road surface displacement X ₀ without requiring complicated operations such determine the transfer force to the vehicle body B Therefore, the control command U ₀ can be obtained. In a system in which there is a time delay from the input of the disturbance until the influence of the disturbance appears in the output, if the control command U ₀ is generated and the actuator A is controlled in this way, the vibration of the vehicle body B caused by the disturbance input is canceled, The vibration of the vehicle body B can be suppressed.

From the above, according to the suspension device (control device) C of the present invention can generate a control command for canceling the effect of disturbance by a simple arithmetic processing, offset the vibration of the vehicle body B by the road surface displacement X ₀ is a disturbance input The vibration of the vehicle body B can be suppressed.

  When the vehicle V is a railway vehicle, the vehicle travels on a fixed track, so the displacement of the track in the travel section can be grasped in advance, and the point information can be obtained from the vehicle monitor. In both cases, the displacement of the track can be grasped, and the control for suppressing the vibration of the vehicle body B can be executed.

Returning to the actual control, it is necessary to consider the dead time τ and the operation delay related to the operation of the actuator A from the control command U ₀ , but as shown in FIG. 3, the control command U ₀ is obtained, It is sufficient to compensate for dead time and operation delay. The dead time and the operation delay may be incorporated in the transfer function Gu from the control command U ₀ to the displacement X _{2 of the} vehicle body B. For the dead time, the sensor 1 is the wheel W has senses road displacement X ₀ of the road surface R passing through the future, the front of the road surface displacement X ₀ by a distance obtained by multiplying the dead time τ from the wheel W to the velocity of the vehicle V If used, dead time can be compensated. The speed of the vehicle V may be obtained from a vehicle speed sensor or ECU (Electronic Control Unit) mounted on the vehicle. Further, regarding the operation delay, when it is incorporated into the transfer function Gu, it may be compensated by incorporating it as a linear model.

  As described above, the model is a single-wheel model, but in order to perform the vibration suppression control of the vehicle body B of the four-wheeled vehicle, the following may be performed. In an actual four-wheeled vehicle, when any one of the four wheels W passes through the unevenness of the road surface R, the influence affects the vibration of the vehicle body B immediately above all the four wheels. In addition, when performing vibration suppression control of the vehicle body B of the four-wheeled vehicle, the suspension device C controls the actuators A interposed between the four wheels W and the vehicle body B, respectively. When any one of the four actuators A is expanded and contracted, the influence affects the vibration of the vehicle body B immediately above all the four wheels.

Therefore, in the case of a four-wheeled vehicle, the road surface displacements of the road surface R through which the four-wheel wheels W pass are X ₀₁ , X ₀₂ , X ₀₃ , and X ₀₄ , respectively, and the vertical displacement of the vehicle body B directly above each wheel W Assuming X ₂₁ , X ₂₂ , X ₂₃ , and X ₂₄ , Expression (1) can be expressed as the following Expression (5). However, Gr _mn is a transfer function from the road surface displacement X _0n to the displacement X _{2m of the} vehicle body B.

また、四輪のアクチュエータＡの制御指令をそれぞれＵ_０１，Ｕ_０２，Ｕ_０３，Ｕ_０４とし、各車輪Ｗの直上の車体Ｂの上下方向変位Ｘ_２１，Ｘ_２２，Ｘ_２３，Ｘ_２４とすると、式（２）は以下の式（６）のように表現できる。ただし、Ｇｕ_ｍｎは、制御変位Ｕ_０ｎから車体Ｂの変位Ｘ_２ｍまでの伝達関数である。

Further, the control commands for the four-wheel actuator A are U ₀₁ , U ₀₂ , U ₀₃ , U ₀₄ , respectively, and the vertical displacements X ₂₁ , X ₂₂ , X ₂₃ , X ₂₄ of the vehicle body B immediately above each wheel W are assumed. Equation (2) can be expressed as Equation (6) below. However, Gu _mn is a transfer function from the control displacement U _0n to the displacement X _{2m of the} vehicle body B.

よって、四輪の場合、式（３）は、以下の式（７）のように表現できる。

Therefore, in the case of four wheels, Expression (3) can be expressed as the following Expression (7).

このように、式（７）を式（４）のように変形すれば、単輪モデルを四輪モデルに拡張して制御指令Ｕ_０１，Ｕ_０２，Ｕ_０３，Ｕ_０４を生成できる。式（７）を式（４）へ変形するには、伝達関数Ｇｕ_ｍｎでなる行列の逆行列を式（７）の右辺へ乗じればよく、そうすれば、路面変位Ｘ_０１，Ｘ_０２，Ｘ_０３，Ｘ_０４から制御指令Ｕ_０１，Ｕ_０２，Ｕ_０３，Ｕ_０４を得られる。

Thus, by transforming Equation (7) as Equation (4), the single wheel model can be expanded to the four wheel model to generate control commands U ₀₁ , U ₀₂ , U ₀₃ , U ₀₄ . In order to transform Equation (7) into Equation (4), the right side of Equation (7) may be multiplied by the inverse matrix of the transfer function Gu _mn , and then the road surface displacements X ₀₁ , X ₀₂ , Control commands U ₀₁ , U ₀₂ , U ₀₃ , U ₀₄ can be obtained from X ₀₃ , X ₀₄ .

  As can be understood from the above description, the suspension device C of the present invention performs control for capturing the road surface displacement as a disturbance and canceling the force (transmission force) transmitted to the vehicle body B in the vehicle V as a system by the input of the disturbance. Running. Therefore, when the actuator A is controlled only by the control, the actuator A cannot exhibit a damping force that attenuates the vibration when the vehicle body B vibrates. Therefore, in consideration of the case where the transmission force is not completely canceled by disturbance input and the vehicle body B vibrates, it is preferable to use skyhook control for suppressing the vibration of the vehicle body B in combination with the control.

In order to perform the skyhook control, the vertical speed of the vehicle body B is detected, and the skyhook control force F (F = −C _S · B _V ) obtained by multiplying the vertical speed B _V by the sky hook damping coefficient C _S. the Request skyhook control command U _S to exhibit to the actuator a. Then, the control instruction obtained by adding the control command U ₀ to exert the transmission force to the skyhook control command U _S as a final control command, it may be given to the actuator A. If skyhook control is used in addition to the control for canceling the transmission force in this way, even if the vehicle body B vibrates, it is possible to effectively suppress the vibration of the vehicle body B by attenuating this vibration.

  In addition, if the suspension device C of the present invention controls the actuator A only by the control to cancel the transmission force, the actuator A cannot exhibit the damping force that attenuates the vibration of the wheel W. Therefore, as shown in FIG. 4, if a dynamic damper D that suppresses the vibration of the wheel W is provided, the vibration of the wheel W can be suppressed.

  The dynamic damper D is composed of a spring 3 and a weight 4 elastically supported by the spring 3 on the wheel W. The spring 3 and the weight 4 have the natural frequency of the wheel W elastically supported by the tire T and the suspension spring S. The natural frequencies of the spring mass system are matched. Thus, if the natural frequency of the dynamic damper D is matched with the natural frequency of the wheel W, 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 only needs to be able to suppress the vibration of the wheel W, and therefore may use a rotary inertia. Furthermore, the dynamic damper D may be configured in parallel with a damper 5 that exhibits a damping force between the weight 4 and the wheel W, as indicated by a broken line in FIG. In the case where the damper 5 is provided, even if the natural frequency of the wheel W and the natural frequency of the dynamic damper D are deviated, there is an advantage that the vibration of the wheel W can be suppressed to some extent without being able to suppress vibration. For damping the wheel W, a suspension built-in wheel as disclosed in Japanese Patent Application Laid-Open Nos. 2003-191702, 2003-191703, or 2003-200302 may be used. Since the dynamic damper D and the suspension built-in wheel do not interfere with the skyhook control, both may be used together with the control for canceling the transmission force.

Further, the suspension device C described above, but the output of the system is the displacement X ₂ of the vehicle body B, as the acceleration or velocity of the vehicle body B outputs may be realized vibration suppression of the vehicle body B.

  Further, in the above description, the present invention has been described by taking the case where the control device is the suspension device C as an example. However, the control device can be used other than the suspension device C of the vehicle V.

  For example, as shown in FIG. 5, the control device 10 can be used to control a mass damper MD that dampens the structure 11. In this case, the control device 10 controls the movable mass 12 that is installed on the structure 11 so as to be movable in the left-right direction in FIG. 5 and the cylinder device 13 that drives the movable mass 12. The control device 10 is installed on the ground G and detects a displacement sensor 14 that detects horizontal and horizontal displacement of the ground G, and a controller 15 that generates a control command to be given to the cylinder device 13 from the ground displacement detected by the displacement sensor 14; It is configured with.

  In this case, the structure 11 can be expressed as a spring mass system in which each layer is expressed as a spring 16 and a mass 17 as in the model diagram shown in FIG. If the displacement of the ground G due to the earthquake motion is a disturbance and the displacement of the top floor of the structure 11 is an output, the structure 11 can be shown as a system in which a time delay occurs until the influence of the input appears in the output. Further, the mass damper MD that is a control target can control the displacement of the uppermost floor of the structure 11 by driving the movable mass 12 with the cylinder device 13. Therefore, the displacement of the ground G due to the earthquake motion is determined by the displacement of the ground G from the transfer function from the disturbance to the displacement of the uppermost floor of the structure 11 and the transfer function from the control command to the mass damper MD to the displacement of the uppermost floor. Control that cancels the transmission force transmitted to the top floor of the object 11 becomes possible. Of course, the speed and acceleration of the ground G may be used as disturbances. Further, the output may be a displacement of a layer other than the top floor of the structure 11 or may be a speed or acceleration of an arbitrary layer of the structure 11.

  As described above, the control device of the present invention can be applied to devices other than the suspension device C, and controls the output of a system in which a time delay occurs even when the influence of the disturbance appears on the output of the system from the input of the disturbance. It can be used to generate control commands to be given to controlled objects, and the influence of disturbance can be removed from the output.

  The control device of the present invention includes a transfer function from disturbance input to system output, a transfer function from control command to output for a controlled object that controls system output, and disturbance information input to the system. Based on the output, the control command for canceling the influence of the disturbance is generated, so that the control command for canceling the influence of the disturbance can be generated by a simple arithmetic process. The disturbance information may be obtained by sensing, or may be held in the control device if known. When the disturbance information is held in the control device, the disturbance information may be referred to as appropriate when the controller 15 controls the mass damper MD that is a vibration control target.

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

  A ... Actuator, B ... Car body, C ... Suspension device (control device), D ... Dynamic damper, R ... Road surface, S ... Suspension spring, T ... Tire, V ... Vehicle (system), W ... Wheel, 2, 15 ... Controller, 10 ... Control device, 11 ... Structure (system)

Claims (4)

A controller for controlling an actuator capable of controlling vibration of a vehicle body in a system having a wheel having a tire traveling on a road surface, a vehicle body, and a suspension spring interposed between the wheel and the vehicle body; ,
The controller is
A transfer function from displacement of the road surface to displacement, speed or acceleration of the vehicle body;
A transfer function from the control command to the actuator to the displacement, speed or acceleration of the vehicle body;
A suspension apparatus that generates a control command based on the displacement information of the road surface. The controller is
The suspension device according to claim 1, wherein a skyhook control command for causing the actuator to exhibit a skyhook control is added to the control command to control the actuator. The suspension device according to claim 1, further comprising a dynamic damper that suppresses vibration of the wheel. A controller for controlling a control target capable of controlling an output in a system in which the influence of the disturbance is output with a time delay with respect to the input of the disturbance;
A transfer function from the input of the disturbance to the output of the system;
A transfer function from a control command to the output to be controlled to control the output of the system;
A control apparatus that generates a control command for canceling the influence of the disturbance from the output based on disturbance information input to the system.

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