JPH0198724A - Vibration control device - Google Patents

Abstract

PURPOSE:To greatly reduce numbers of sensor by presuming physical quantity affecting suspension character through presuming other quantity of state necessary for getting aimed braking force based on detected quantity of state on a state detecting means. CONSTITUTION:Other quantity of state for getting aimed braking force with a quantity of state presuming means II0 in a control means II, for instance, presumed suspended speed and the like is operated from quantity of state X detected by a state detecting means I, namely from relative displacement between a wheel axle and a car body while an automobile is running, again physical quantity affecting suspension character is presumed by a control force presuming means II'2, while presumed control force signal corresponding to the presumed physical quantity is output, and optimum aimed control force is operated by an aimed control force operating means II2. And with driving an actuator means IV attached to the suspension via a deviation calculating means II3 and a drive means III, suspension character is optimum variable controlled continuously. In such way, reliability on suspension can be improved with little numbers of sensor.

Description

Detailed Description of the Invention (Field of Industrial Application) The present invention relates to a vibration control device for suppressing vibrations caused by external forces or disturbances (road surface) in a support device for a building or a traveling device. It is something to do.

(Prior art and its problems) Conventionally, as vibration control devices, active control devices have been used that control vibration by forcibly applying a large amount of energy to external forces or disturbances using pressure from a hydraulic source or the like from outside the suspension. The system identifies the vibration state and selects an appropriate one from among two or three preset damping characteristics based on the output, changes the damping force characteristics using a small amount of energy, and controls the vibration suppression effect. Semi-active control type devices that control sprung mass fi@ji, and part-active control type devices that suppress sprung mass fi@ji by directing part of the energy from a hydraulic source installed outside the suspension as necessary in response to external force or disturbance. There is.

However, these conventional vibration control devices are active control devices that always use the pressure of the hydraulic source to control the control force acting on the suspension, and the hydraulic source consumes a large amount of energy. There was a problem in that the number of components such as the pump and tank pressure accumulator increased, resulting in a larger size and higher cost.

In addition, semi-active control devices use a discontinuous control method, so even though they have the effect of suppressing vibration, they apply the optimal target control force that takes into account various external forces or disturbances to achieve the optimal damping force characteristic control force. It does not control the damping force characteristics optimally for the effect of the damping force, and there is a problem in that it is not possible to sufficiently suppress the agitation. Furthermore, with part-active control devices, only a portion of the target control force is applied externally, so sufficient vibration control cannot be achieved, and furthermore, since it is discontinuous control, it is difficult to handle fine vibrations at high frequencies. There was a problem that it could not be followed.

In short, the main problem with conventional devices is that devices using semi-active control and part-active control do not control the entire control force for vibration suppression, but control only a part of the total control force for the purpose. Because the target was controlled discontinuously, it could not be completely controlled.
On the other hand, in devices using active control, the control force necessary for vibration suppression can be directly controlled as desired, but a large amount of power is constantly required for control, making the device large-scale.

In view of the problems of the prior art, the inventor of the present application first
We have developed a vibration control device that solves these problems (Japanese Patent Application Laid-open No. 108319/1983). As shown in Fig. 2, this vibration control device includes a state detection means (1) that detects physical quantities that affect the characteristics of the suspension that supports the vibrating body, and a state quantity that indicates the movement of the suspension; target control force calculation means (1) which calculates an optimal target control force from physical quantities and state quantities which are the outputs of the suspension in consideration of external forces or disturbances acting on the suspension; and a detected control force corresponding to the physical quantities detected by the state detection means I. A control means (■) consisting of a detection control force calculation means (2) for calculating the difference between the target control force and the detected control force, and a deviation calculation means (3) for calculating the deviation between the target control force and the detection control force; A driving means ■ that amplifies the power of the deviation signal, and a control force that equivalently generates a control force corresponding to the deviation of the actual detected control force from the target control force that takes into account the external force or disturbance acting on the suspension based on the power amplified output. actuator means for continuously variable control of the characteristics of the suspension, and equivalently generates a control force corresponding to the difference between the detected control force and the target control force that takes into account external forces or disturbances acting on the suspension. Since the characteristics of the suspension are continuously and variably controlled in this manner, the vibration control device suppresses vibration by equivalently applying a target control force to the suspension.

This vibration control device extracts the force between the physical quantity f from the optimal target control force and controls the physical quantity.
Compared to conventional vibration control devices, it allows fine control of the physical quantity f in consideration of external forces or disturbances, reduces energy consumption, simplifies the configuration, and reduces the weight, space, and cost of power sources, piping, etc. be.

(Problem to be solved by the invention) However, in this device, the state quantity indicating the movement of the suspension necessary to obtain the optimal target control force for continuously changing the suspension characteristics, and the All physical quantities given had to be detected. Therefore, a large number of sensors and a large number of signal lines are required, which increases the length of the signal lines, increases the possibility of noise intrusion, and reduces accuracy. Additionally, the reliability of the sensor is required to be ensured, resulting in an increase in cost. Furthermore, if control is performed without obtaining the optimum target control force due to deterioration or failure of the sensor, there is a problem in that ride comfort and running stability are significantly impaired.

Therefore, the present invention aims to solve the above problems. In other words, the purpose is to obtain the various quantities necessary to calculate the optimal target control force using the minimum number of detectors necessary, simplify the configuration, ensure reliability, and perform stable control. shall be.

(Means for Solving the Problems) As shown in FIG. 1, the vibration control device of the present invention includes a state detection means I for detecting a state quantity indicating the movement of a suspension supporting a photographing object, and a state detection means control force estimating means 112' which estimates a physical quantity that affects the suspension characteristics based on the state quantity output signal outputted by (1) and obtains a control force corresponding to the estimated quantity of the physical quantity; and the state outputted by the state detection means I. State quantity estimating means for estimating other state quantities necessary to obtain the target control force based on the quantity output signal■
o, a state quantity output signal outputted by the state detecting means (2), and the state quantity estimating means (2). a target control force calculation means (1) for calculating an optimal target control force by considering an external force or disturbance acting on the suspension from the state estimation amount outputted by the control force estimation means II2' and the estimated control force signal outputted by the control force estimation means II2'; A control means (■) consisting of a deviation calculation means (3) for calculating the deviation between the target control force outputted by the target control force calculation means (1) and the estimated control force outputted by the control force estimation means II2'; and the control means (2). A driving means (■) for power amplifying the deviation signal of the opening control force which is the output of the control force estimating means I[2' for the target control force which takes into account external force or disturbance acting on the suspension based on the power amplified output. Actuator means for continuously variable control of the characteristics of the suspension so as to equivalently generate a control force according to the deviation of the estimated control force, and a target control force and control force that take into account external forces or disturbances acting on the suspension. The characteristics of the suspension are continuously and variably controlled so as to equivalently generate a control force according to the difference between the estimated control force outputted by the estimation means, and as a result, the target control force is equivalently added to the suspension. This suppresses vibration.

(Function) In the above configuration, the state fi indicating the movement of the actuator means ■ which generates the specific state quantity which is the output of the state detection means ■, that is, the control force f acting on the suspension.
As the number between xs and the state quantity X that depends on the type of control force,
The control force f (Xs +

It is expressed as Further, in the case of the damping force fc, if the suspension speed is y, it is expressed as fC(X!+y). Therefore, as a state quantity! , and X are detected, the control force f can be estimated.

Furthermore, by detecting acceleration as a state quantity with the state detection means (2), velocity can be estimated by first-order integration, and displacement can be estimated by second-order integration.

From the above, the state X in which all the state quantities necessary for calculating the optimal target control force U determined by the target control force calculation means (1) are the outputs of the state detection means (2), and the state quantity estimating means (2). The optimum target control force U can be calculated because the estimated state quantity X, which is the output of

Once the optimal target control force U is determined, the deviation ε from the estimated control force is output in step 3, the drive means 2 amplifies the power, and the actuator 2 attached to the suspension is driven to adjust the suspension characteristics. Continuously optimally variable control.

(Effects of the Invention) The present invention provides, based on the state quantity detected by the state detection means,
The other state quantities necessary to obtain the target control force are estimated and found by the state quantity estimation means, and the physical quantities that affect the suspension characteristics are estimated and found by the control force estimation means, so the target control force can be estimated. The number of sensors for obtaining state quantities and physical quantities required for calculation can be significantly reduced. Therefore, the possibility of noise being mixed in from the sensor and the signal line connected to it is reduced, and reliability can be significantly improved. Further, there is an advantage that the configuration is simple and costs can be reduced.

[First Embodiment] In the first embodiment of the present invention, the control force estimating means U2J in the basic configuration of FIG. 1, as shown in FIG. a first coefficient setting means 11 and a second coefficient setting means 12 for setting two coefficients necessary for estimating a physical quantity based on the state; a state variable calculation means I3 for calculating a state variable by time-differentiating the state quantity output signal; The state quantity output signal outputted by the detection means I and the first coefficient setting means 1! and an estimated physical quantity calculation means 14 that calculates an estimated physical quantity using the two coefficients outputted by the second coefficient setting means 12 and the state variable outputted by the state variable calculation means 13, and an estimated physical quantity signal outputted by the estimated physical quantity calculation means 14. and an estimated control force calculating means 15 for obtaining a corresponding control force, and a state quantity estimating means (2). A first integrating means 16 that time-integrates the state quantity output signal outputted by the state detecting means (2), and a second integrating means 16 that time-integrates the signal outputted from the first integrating means 16.
It consists of an integrating means 17.

1. In the control force estimating means I[2', in order to obtain the estimated value of the physical quantity from the state quantity output signal outputted by the state detection means ■, two obtaining a numerical value between the first coefficient setting means and the second coefficient setting means,
Further, the state quantity output signal outputted by the state detection means (2) is obtained by a state variable calculation means 13 which calculates a state variable by time-differentiating the signal measured in accordance with the control period,
Estimated physical quantity calculation means 14 obtains estimated values of physical quantities from the above three parties. Based on this estimated physical quantity signal, the estimated control force calculating means 15 calculates the corresponding control force.

State quantity estimation means■. , the estimated values of the first and second state quantities are obtained by the first and second integrating means 16 and 17 using the state quantity output signal outputted by the state detection means (■), and these physical quantities and state am are calculated. From the estimated value and the state quantity output signal output from the state detection means I, an input signal to the target control force calculation means (1) necessary to obtain the target control force is obtained.

The first embodiment, which has the above configuration 9 effects, can significantly reduce the number of outputs generated by the state detection means (2), and therefore reduces the number of signal inputs that always occur when the state detection means (2) is installed. Since the amount of noise etc. in the line is reduced, this control system can be operated stably and the control can be continued safely, which has the advantage that accurate control can be realized.

[Second Embodiment] The second embodiment of the present invention is state quantity estimating means (2) in the basic configuration of FIG. is connected to the control force estimating means 112' as shown in FIG.
an abnormality determining means 21 for determining whether the state am output signal outputted by is an abnormal value; and the control force estimating means II2 when the abnormality determining means 21 determines that the state quantity output signal is an abnormal value. ' outputs the estimated control force output by
A signal selection means 22 that outputs a state am output signal when the abnormality determination means 21 determines that the state quantity output No. 18 is not an abnormal value, and a target control force is obtained based on the signal output by the signal selection means 22. and a state quantity calculating means 23 for estimating other state quantities necessary for the process.

The nine-plate abnormality determination means 21 determines whether the output of the state detection means I is an abnormal value or not, and outputs a determination signal thereof. The signal selection means 22 is based on the output of the abnormality determination means 21, and in the normal state is based on the output signal itself of the state detection means I.
Based on the output signal of the control force estimating means 2', which outputs an output signal so that the state quantity calculation means 23 performs the state quantity estimation calculation, and obtains the control force corresponding to the aforementioned physical quantity estimation in an abnormal state, An output signal is output so that the state quantity calculation means 23 performs the state quantity estimation calculation.

The state quantity calculation means 23 estimates and calculates other state quantities necessary to obtain the target control force based on the output signal of the signal selection means.

Effect-1: Due to the above-mentioned configuration 9 effects, the second embodiment makes it possible to calculate the target control force even if the output of the state detection means I shows an abnormal value and a failure occurs.
This has the advantage that stable control can be guaranteed, and even if a state outside the measurable range of the state detector occurs, stable control can be continued, and reliable control can be achieved.

(Specific Embodiments) First Embodiment> A vibration control device according to the present invention is as shown in FIG. 5(a).
This embodiment is applied to a gas-liquid fluid suspension device for an automobile in which an orifice 39 is disposed in the middle of an oil passage or pipe 40 that communicates between a hydraulic cylinder 37 and a gas-liquid fluid spring 38. Here, wheel suspension will be representatively explained using FIGS. 5 to 7.

The vibration control device of this embodiment includes a state detection means (2), a control means (2), a drive means (2), and an actuator means (2).

The control means (■) consists of a state quantity estimation means (■o), a target control force calculation means (■), an ivt force estimation means (■2'), a deviation calculation means (■3), and a sign adjustment means (■4). I have it.

As shown in FIG.
2 and the vehicle body frame 33 to detect relative displacement, and the potentiometer 3
1, and outputs a signal representing the relative displacement y between the axle and the vehicle body when the automobile is running; and a differentiator 42, which differentiates the relative displacement y output from the amplifier 41 and detects the relative speed y. , an acceleration sensor 43 that is attached to the vehicle body directly above the suspension to detect acceleration, an amplifier 44 that is connected to the acceleration sensor 43 and converts it into a voltage signal, a displacement sensor 45, and an amplifier 46 that outputs a signal representing displacement. . The displacement sensor 45 is connected to a linear actuator 47 and a valve body 48 as shown in FIG. 5(b).
In the actuator means (2), the displacement of the sub-hole 49 which continuously opens and closes the oil passage 40 to form a variable orifice is detected by a magnetic detection means comprising a permanent magnet 50 and a moving coil 51.

The control force estimating means II2' calculates the spool displacement X of the linear actuator 47 output from the amplifier 46.

a computing unit 52 that computes the estimated damping force fc from
It consists of

The estimated damping force fc is the differential pressure Δ between the front and rear oil passages of the variable orifice.
p is multiplied by the piston cross-sectional area A of the hydraulic cylinder 37.

fc=ΔPA・・・・・・・・・・・・・・・
(1) The pressure difference ΔP is given by the following equation, where Q is the flow rate passing through the variable orifice.

Here, a(XS): orifice area of the variable orifice, c: flow coefficient of the variable orifice section, and ρ: oil density.

The flow rate Q is expressed by the following equation using the piston speed of the hydraulic cylinder 37, that is, the relative speed obtained by differentiating the relative displacement y between the axle and the vehicle body.

Q=Ay・・・・・・・・・・・・
・・・・・・・・・・・・ (3) Therefore, the estimated damping force fc is (1), (2).

From equation (3), it is given as the following equation.

fc ”K (Xs) y2 ・・・・・・・・・
・・・・・・・・・(4) Here, ρ K (xs) = −(C-A-a (Xs)'
t2...(5).

However, the actual damping force fc depends on the spool displacement X, and the flow coefficient C is not constant, and as shown in FIG. 5, the actual orifice area is Since the gain is larger than the design value and due to dimensional tolerances etc., the gain K<
xs) is difficult to calculate. Therefore, the relationship between the damping force and the spool displacement (X) and the relative speed (y) are experimentally investigated, and an experimental formula is derived as shown below.

f c =K(,xs)・y"1(X"...
・--(6)^ Here, the characteristics of gain K(xt) and index n(xs) are:
It varies depending on the orifice shape design, and an example is shown in FIG.

State quantity estimation means■. a bypass filter 53 that removes the DC component of the °2 signal from the sprung acceleration output from the amplifier 44; a first integrator 54 that integrates the output to calculate the estimated spring improvement X; and a second integrator 55 that integrates the output to calculate the estimated sprung mass displacement x2.

The target control force calculation means 1 calculates the optimum target control force U according to the following formula from the optimum gains G1 to G, s obtained in advance from a model assuming active control and the corresponding state signal.
Five multipliers 56 to 60 and an adder 6 for calculating
Consists of 1.

Gu"Gt@y+Gz"3/+Ga"X2+G4"
X2+Gs red fc ・・・・・・・・・・・・・・・
(7) The deviation calculation means (■3) includes a deviation device 62 that calculates the deviation ε between the damping force fc to be controlled and the optimal target control force U output from the target control force calculation means (■1).

The sign adjustment means (4) is composed of a multiplier 63 that multiplies the output ε of the deviation device 62 by the suspension speed n. It determines whether the deviation ε from the target control force can be controlled by the damping force, and if it is controllable, it outputs a signal that determines the direction of increase or decrease of the damping force, and if it cannot be controlled, it reduces the damping force. The purpose is to output a signal in a direction that approaches zero.

The sign adjustment function of the multiplier 63 will be explained using the table and FIG. 5(a). When the target control force U is positive in the upward direction perpendicular to the vehicle body and also in the direction of suspension compression, the target control force U and the relative speed N are both in the same direction, for example, when the piston of the hydraulic cylinder 37 is When the movement is upward (positive direction) and the target control force U signal is also upward (positive direction), the oil in the hydraulic cylinder 37 flows through the orifice 39 to the gas-liquid fluid spring 38 in proportion to the relative speed. In this case, by changing the opening degree of the orifice 39 using a control signal, the pressure inside the hydraulic cylinder 37, that is, the damping coefficient, and the magnitude of the upward (positive direction) damping force fc can be changed. , when the output ε of the deviation device 62 is positive (u>f(), the orifice opening is set in the closing direction, the damping coefficient is increased to increase the damping force, and ε is negative (u<fc)
Then, it is sufficient to set it in the opening direction and output a control signal to reduce the damping force by decreasing the damping coefficient. Further, the piston of the hydraulic cylinder 37 moves downward (negative direction),
If the target control force U signal is also downward (negative direction),
Contrary to the above, oil flows from the gas-liquid fluid spring 38 through the orifice into the hydraulic cylinder 37, so by similarly controlling the orifice opening degree, the magnitude of the downward (negative direction) damping force fc can be changed. be able to. Also in this case,
When ε is positive (-u > -f c ), the orifice opening is set in the open direction, the damping coefficient is made small, and the damping force is reduced.
If ε is negative (-U<-rc), it is necessary to set it in the closing direction and output a control signal that increases the damping coefficient and the damping force that equivalently acts on the suspension.

Therefore, when the target control signal U and the suspension relative speed i are in the same direction, the damping force fC is based on the target control force U.
can be controlled. On the other hand, if the target control force U and the relative speed y are in opposite directions, for example, the piston of the hydraulic cylinder 37 moves upward (positive direction), and the target control force U moves downward (negative direction), the oil in the hydraulic cylinder 37 enters the Jjc liquid fluid spring 120 through the orifice 39,
If the orifice opening is kept at a certain degree (not controlled), an upward (positive direction) damping force will act along with the relative speed, and the damping force will be controlled based on the target control force 1. Can not do it.

Therefore, if the orifice opening is set to all levels using a control signal and the damping coefficient is minimized to reduce the positive damping force fc that equivalently acts on the suspension, it will be as if the damping force fc is the same as when no control is applied. This corresponds to applying a force in the direction of the control force U and reducing it. At this time, the output ε("u-fc) of the deviation device 62 is, since the target control force U is negative and fc is positive from the same direction as the relative speed C.
Always negative. Further, the piston of the hydraulic cylinder 37 moves downward (negative direction), and the direction of the target control force U changes upward (
(positive direction), it is not possible to control the damping force based on the target control force U in the same way as above, so the orifice opening degree is fully opened using the control signal, and the damping coefficient is minimized to provide an equivalent effect to the suspension. It is desirable to reduce the damping force acting on the output ε(=
u − f c ) is always positive because the target control force U is positive and fc becomes negative in the same direction as the relative speed y. Therefore, when the target control force U and the relative speed y are in opposite directions,
Since it is not possible to control the damping force based on the target control force U, the orifice opening degree is fully opened using the control signal.
This means that the damping force should be reduced.

As described above, the control direction of the damping force and the orifice opening degree with respect to the output ε of the deviation device 62 in each state is summarized as shown in the table. To basically achieve this logic, by multiplying the sign of ε by the sign of the suspension relative speed y, which is in the same direction as the damping force, the output is a control signal corresponding to the control direction of the orifice opening. becomes. Here, it is sufficient that the control signal determines the direction of increase/decrease of the damping force, and in order to improve the ratio of the noise to the difference ε signal with respect to the target control force, that is, the S/N ratio, the multiplier 63 directly applies the signal to ε. ε, which is multiplied by the relative prime y, was used as the control signal.

The drive means m comprises a drive circuit 64 which provides negative feedback of the spool displacement signal of the actuator means (2) to the output of the deviation device 62 and outputs a current proportional to the deviation signal.

As shown in FIGS. 5 and 6, the actuator means (2) is a hydraulic cylinder 37 of the gas-liquid fluid suspension attached to the suspension arm 32 and the vehicle body frame 33.
A valve body 48 integrated with the valve body 48, an oil passage 40 that communicates the oil chamber of the accumulator 38 and the oil chamber of the hydraulic cylinder 37 through the valve body 48, and the oil passage 40.
A spool 49 that is continuously closed and closed to form a variable orifice, and a linear actuator 4 integrated with the spool.
7, a permanent magnet 50 that applies a force to the moving coil 51 according to the current output from the drive circuit 64 flowing through the moving coil, and a permanent magnet 50 that is attached to the linear actuator 47 to suppress the force that acts on the moving coil. A displacement sensor 45 detects the displacement of the spool.
and an amplifier 46 that outputs a signal representing displacement.

The operation of the first embodiment having the above-described configuration is as follows.

When the vehicle is running, an amplifier 41 converts a relative displacement amount (suspension displacement) y detected by a linear potentiometer into a voltage signal, and a differentiator 42 differentiates the output to obtain a relative speed signal i.

On the other hand, the spool displacement of the linear actuator 47 is detected by an inductance type contact displacement sensor, and the amplifier 46 converts it into a voltage signal to generate a spool displacement signal X.

is obtained. Based on this signal and the relative velocity Ω obtained earlier, the estimated damping force fc is obtained by calculating in the calculator 52.

When calculating the estimated sprung mass velocity x2 by integrating the sprung mass acceleration signal and the estimated sprung mass displacement x2 by further integrating the signal, if there is a slight offset potential at the output of the amplifier 44, the estimated sprung mass displacement obtained by the second-order integration Since the signal x2 causes a large drift, if the signal is used as it is for control, it will adversely affect ride comfort and steering stability. Therefore, as shown in FIG. 6, the amplifier 44 and the first integrator 5
A bypass filter 53 was provided between 4 and 4. The order of the bypass filter 530 is 1st order, and the cart frequency is a frequency range that does not adversely affect the suspension characteristics.
The frequency was chosen to be 0.1 Hz.

From the signals of the relative displacement y, relative velocity y, and estimated fc obtained above and the optimal gains 01 to G5, the optimal target control force 1 is calculated based on the formula (2) above, and the output of the adder 61 is can get. The deviation between the output of this target control force U and the estimated damping force fc to be controlled is taken, and the deviation is multiplied by the relative speed i in a multiplier 63 to convert it into a damping force control signal, and the output is By moving the drive circuit 64 accordingly, the damping coefficient changes and the damping force fc can be changed continuously.

The advantages of the first embodiment are as follows. When calculating the sprung mass velocity and sprung mass displacement from the sprung mass acceleration signal detected by the acceleration sensor, the first integrator 54. The second integrator 55 is generally used, but if there is a slight drift in the output voltage due to the amplifier 44 itself, the output of the integrator may become saturated due to the high integral gain in the second-order integrated sprung mass displacement calculation. be. Therefore, by passing the output of the amplifier 44 through the primary bypass filter 53 having a frequency of 0.1 Hz, it is possible to stably estimate the sprung mass speed and the sprung mass displacement output. On the other hand, in estimating the damping force as well, by using an empirical formula, a more accurate damping force can be estimated and calculated.

By using these state estimation calculation methods, stable output can be obtained and it is possible to estimate changes in state quantities that are almost the same as actual changes in state quantities, making it possible to control damping force that adapts to riding comfort and driving conditions. . As a result, the vibration of the vehicle can be reduced, and ride comfort, running stability, etc. can be significantly improved.

Second Embodiment The second embodiment, like the first embodiment shown in FIG. 6, is embodied in a gas-liquid fluid suspension system for an automobile, and is configured as shown in FIG. 8. . The major difference from the first embodiment shown in FIG. 6 is that the control means
is replaced with a microcomputer 70, the oil temperature is detected by the oil temperature sensor 13 attached to the hydraulic cylinder 37,
The two points are that the estimated damping force fc is subjected to temperature compensation, and that the actuator that controls the damping force is replaced with a pulse motor.

First, the actuator means (2) for controlling the damping force will be explained with reference to FIGS. 8 and 9.

Inside the hydraulic cylinder 110 of the air 82 fluid suspension attached to the suspension arm 32 and the vehicle body frame 33, there is an orifice 112, an opening/closing plate 113, a rotary shaft 114 integrated with the opening/closing plate 113, and a rotary shaft 114 connected to the rotary shaft 114. It consists of a pulse motor 80. Therefore, when the rotary shaft +14 is rotated by the pulse motor, the opening/closing plate 113 is rotated, and the opening area of the orifice +12 is continuously varied, thereby forming a variable orifice.

Next, the state detection means I includes a potentiometer 31 that detects relative displacement as in the first embodiment, an amplifier 41 that converts the movement of the potentiometer 31 into a voltage signal, and is attached to the vehicle body directly above the suspension to detect sprung mass acceleration. In addition to the acceleration sensor 43 that is connected to the acceleration sensor 43 and the amplifier 44 that is connected to the acceleration sensor 43 and converts it into a voltage signal, an oil temperature sensor 81,
Amplifier 8 that connects with oil temperature sensor 81 and converts it into a voltage signal
It consists of 2.

Control means ■ is state quantity estimation means ■. , a target control force calculation means (2), a control force estimation means 112', a deviation calculation means (3), and a sign adjustment means (4). This microcomputer includes a human power unit 71 that takes in relative displacement y, sprung mass acceleration)°2, and temperature t, an arithmetic processing unit 72 that performs calculations for the control means H based on these state signals, and stores the calculation method. The output unit 74 outputs the damping force control signal calculated by the calculation processing unit 72 as a pulse signal. Here, details of the functions performed by the microcomputer 70 will be explained in the flowchart of FIG.
This will be explained using Figure 1.

After initialization with PO, the data of relative displacement y, sprung mass acceleration 2, and oil temperature t are taken in with PI. Next, in Pl, P
The cut frequency is 0.
The signal x2 is passed through a 1 Hz first-order bypass filter.

The transfer characteristic of the first-order bypass filter using the Laplace operator S is as follows.

Here, T: time constant When formula (8) is transformed into the output formula of the bypass filter, the following formula is obtained.

However, for the integral gain, = −・・・・・・・・・・・・・・・・・・・・・・
......(10).

Therefore, the calculation of the first-order bypass filter output is (9
) based on the formula. In addition, T = 1.
It will be 59 seconds.

Next, in P3, the bypass filter output calculated by P1)
The estimated sprung improvement degree cross is calculated by first-order integration of °2, and the estimated sprung mass displacement X2 is calculated by first-order integration.

Next, in P4, the relative displacement y taken in by Pl is differentiated to calculate the relative velocity.

As mentioned above, P2 to P4 are the bypass filter 53 of the first embodiment shown in FIG. First integrator 54. The analog calculations by the second integrator 55 and the differentiator 42 are simply replaced with digital calculations.

At P5, the damping force is estimated from the relative velocity y calculated at P4, the oil temperature t taken at Pl, and the orifice opening area. Here, since a pulse motor is used as the actuator means (2), the orifice opening area is expressed as a number between the pulse motor rotation angle θ, and the rotation angle θ is P
Pulse motor rotation angle control signal θ output at O. matches. Therefore, since the orifice frontage area a(θ) is known, the estimated damping force fc when the reference oil temperature t is t=tn can be calculated using the empirical formula (6) shown in the first embodiment between θ. It is determined by the following equation as a number.

・n(θ) fc=K (θ)y ・・・・・・・・・・・・
(11) Here, the damping force with respect to the relative speed and the rotation angle θ is calculated in advance based on the equation (1), and the calculated values are mapped with respect to θ and i.

Next, when the oil temperature changes, the oil density ρ changes as follows.

ρ=ρ. -kt ・・・・・・・・・・・・・・・
(12) where ρ is the oil density when the oil temperature is 0° C. As an example, the change in oil density ρ with respect to the oil temperature is shown in FIG. 11. Therefore, the gain K(θ) in equation (1) is proportional to the oil density ρ, as shown in equation (5), and therefore changes in accordance with changes in oil temperature.

Therefore, the oil temperature t is detected, the oil density ρ is calculated from equation (12), and the density ratio ρ/ρn between that value and the density ρn at the reference oil temperature is calculated using equation (1). Estimated damping force fc By multiplying and summing together, the damping force fc' corresponding to the oil temperature change can be calculated. That is, fc' becomes the following formula.

ρn At P6, the optimal target control force U is calculated using the equation (7) shown in the first embodiment, and at Pl, the damping force to be controlled with respect to the optimal target control force U, that is, the damping force fc' determined at P5. Calculate the deviation ε from

Next, in P8, the deviation ε obtained in Pl is multiplied by the relative velocity Q obtained in P4 to calculate εy, which is used as the rotation angle control signal θゎ of the pulse motor. This is the same reason as in the first embodiment, so the explanation will be omitted here.

In PO, θ determined in P8. The signal line is switched to the CR for clockwise rotation or the CCR for counterclockwise rotation of the pulse motor depending on the direction of , and at the same time a pulse proportional to the magnitude of θ is output.

The driving means (2) includes a driving circuit 64 connected to the CR and CCR signal lines output from the microcomputer 70 and outputting a current pulse corresponding to the pulse signal.

The operation of the second embodiment having the above-described configuration is as follows. After initializing at PO, the microcomputer outputs the relative displacement signal y detected by the linear potentiometer at Pl, the oil temperature signal t detected by the oil temperature sensor attached to the hydraulic cylinder, and the spring ball detected by the continuity sensor. Data of the acceleration signal)° is sampled every 10 m5ec.

After calculating the output ゛x°2 of the first-order bypass filter with the sprung mass acceleration ~° with Pl, the estimated sprung mass velocity is calculated with P3, and then P
After calculating the relative velocity in step 4, calculate the output and the previous one step (1
Based on the magnitude of the pulse motor rotation angle control signal θc (=θ) calculated in P8 before 0 m5ec), the estimated damping force fc at the standard oil temperature tn is read out from a pre-stored map. Then, this value is multiplied by the oil density change ρlρn obtained from the detected oil temperature t to obtain the temperature-compensated estimated damping force fc'.

Next, P6 is the optimal target control force U, Pl is the deviation, P8
is the pulse motor rotation angle control signal θ. seek.

And finally, CR for clockwise rotation according to the output obtained in P8.
Alternatively, a CCR pulse for counterclockwise rotation is output.

As above, the execution from P1 to P9 is completed within 10 m5ec, and the process returns to PI again.

A pulse motor 80 is driven by driving a clockwise or counterclockwise rotation pulse output from the microcomputer by a drive circuit 64. By rotating the pulse motor, the orifice opening area a(θ) is continuously changed. That is, the damping coefficient changes and the damping force can be changed continuously.

The second embodiment has the following advantages. That is, in addition to the advantages of the first embodiment, the oil temperature t in the hydraulic cylinder is detected;
By adding temperature compensation to the estimated damping force fc, it is possible to estimate the damping force actually occurring in the suspension, and it is possible to obtain a control force close to the ideal optimal target control according to the ever-changing road surface conditions. This allows damping force control to be adapted to all driving conditions. As a result, there is an advantage in that it is possible to reduce the number of images taken of the vehicle and to significantly improve ride comfort, running stability, and the like.

Furthermore, since a pulse motor is used as the actuator means, minor loop control for detecting and feeding back the rotation angle of the motor is unnecessary, and the circuit configuration can be simplified.

Furthermore, since the calculations of the differentiator 42 and the control means (2) of the first embodiment shown in FIG. This has the advantage of eliminating the need for analog multipliers, reducing space and cost.

[Brief explanation of the drawing]

FIG. 1 is a schematic configuration diagram of the present invention, FIG. 2 is a schematic configuration diagram showing a conventional technique, FIG. 3 is a schematic configuration diagram showing a first embodiment of the present invention, and FIG. 4 is a second embodiment of the present invention. 5(a) is a schematic configuration diagram of an automobile gas-liquid fluid suspension according to a first embodiment of the present invention; FIG. 5(b) is a sectional view of an actuator means according to a first embodiment; FIG. Figure 6 is a system configuration diagram showing the entire first embodiment, Figure 7 shows the relationship between spool displacement and damping force in the gas-liquid fluid spring, and Figure (a) shows the relationship between spool displacement and gain; FIG. 5B is a diagram showing the relationship between spool displacement and index. FIG. 8 is a block diagram showing the configuration of the second embodiment, and FIG. 9 (
a) is a sectional view of the actuator means of the second embodiment, FIG. 10(b) is a sectional view taken along line A-A in FIG. , FIG. 11 is a diagram showing changes in oil density with respect to oil temperature. I...State detection means, ■...Control means, ■. ...
State quantity estimation means, ■1...Target control target calculation means, 11
2'... Control force estimation means, ■3... Deviation calculation means,
■... Drive means, ■... Actuator means, 11
... first count setting means, 12 ... second count setting means, 13 ... state variable calculation means, 14 ... estimated physical quantity calculation means, 15 ... estimated control force calculation means, 16 ...・
first integrating means, 17... second integrating means; Applicant Toyota Central Research Institute Co., Ltd. Toyota Motor Corporation Figure 5 (a) (b) 45-branch at-, 47-1 Nonia Akiko Yueta-Bubble Body I 49-Suar 50. −＊
Kumagnet 51 - Mugo) Fool'11 with Gecoil] l1fLfLixs Figure 9 (a) Figure 10

Claims (3)

[Claims] (1) A state detection means for detecting a state quantity indicating the movement of a suspension that supports a vibrating body, and estimating a physical quantity that affects suspension characteristics based on a state quantity output signal outputted by the state detection means, and estimating the physical quantity. control force estimating means for obtaining a control force corresponding to the amount; state quantity estimating means for estimating another state quantity necessary to obtain the target control force based on the state quantity output signal outputted by the state detection means; Optimum target control force is determined based on the state quantity output signal outputted by the detection means, the estimated state quantity outputted by the state quantity estimating means, and the estimated control force signal outputted by the control force estimating means, taking into account the external force or disturbance acting on the suspension. and a deviation calculation means that calculates a deviation between the target control force output by the target control force calculation means and the estimated control force output by the control force estimation means; A drive means for power amplifying a deviation signal between both control forces, which is an output of the control means; and an estimated control output by a control force estimating means for a target control force that takes into account an external force or disturbance acting on the suspension based on the power amplified output. actuator means for continuously variable control of the characteristics of the suspension in order to equivalently generate a control force according to the deviation of the force; Since the characteristics of the suspension are continuously variable controlled to equivalently generate a control force corresponding to the difference between the estimated control force and the estimated control force to be output, as a result, vibration is reduced by equivalently adding the target control force to the suspension. A vibration control device characterized by suppressing. (2) The control force estimating means includes first coefficient setting means and second coefficient setting means for setting two coefficients necessary for physical quantity estimation based on the state quantity output signal outputted by the state detection means, and the state quantity output signal a state variable calculation means for calculating a state variable by time-differentiating the state variable, a state quantity output signal outputted by the state detection means, two coefficients outputted by the first coefficient setting means and the second coefficient setting means, and the state variable calculation means. The state quantity estimating means includes: an estimated physical quantity calculating means for calculating an estimated physical quantity using a state variable outputted by the estimated physical quantity calculating means; and an estimated control force calculating means for obtaining a control force corresponding to an estimated physical quantity signal outputted by the estimated physical quantity calculating means; Claim 1 comprising: a first integrating means for time-integrating the state quantity output signal outputted by the state detecting means; and a second integrating means for time-integrating the signal outputted by the first integrating means. The vibration control device described in (1). (3) The state quantity estimating means is connected to the control force estimating means, and includes an abnormality determining means for determining whether the state quantity output signal outputted by the state detecting means is an abnormal value; The control force estimating means outputs an estimated control force when the quantity output signal is determined to be an abnormal value, and the state quantity is output when the abnormality determining means determines that the state quantity output signal is not an abnormal value. The present invention is characterized in that it comprises a signal selection means for outputting an output signal, and a state quantity calculation means for estimating other state quantities necessary to obtain a target control force based on the signal outputted by the signal selection means. Range number (
The vibration control device described in section 1).