JP2000018315A - Active controller - Google Patents

Abstract

PROBLEM TO BE SOLVED: To suitably execute correction of change in an estimated transfer function against change of a environment in use for a vehicle, change with the lapse of hours, or the like without making occupants uncomfortable. SOLUTION: An actuator 23 is excited according to the signal of a frequency selected at random within a predetermined frequency for the short time under the driving of an engine 11 in a vehicle, a response by excitation is measured to calculate an estimated transfer function, the estimated transfer function which is calculated is compared with the data of the estimated transfer function which is memorized, and the entire data of the estimated transfer function which is memorized is updated on the basis of this estimated data. All data on the estimated transfer function to be memorized are updated on the basis of the estimated data. Excitation operation is informed to the occupants without making the occupants uncomfortable because the estimated transfer function is measured in a short time. Moreover, the capacity of a data table RAM 41 for temporarily memorizing the measurement data of the estimated transfer function can be decreased, and the memory cost of a control unit 31 can be decreased. In addition, the estimated transfer function can be maintained in a most suitable state, and proper adaptable control can be executed.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an active control device for actively suppressing vibration of a vehicle body.

[0002]

2. Description of the Related Art Conventionally, an active control system for an engine mount of a vehicle has an adaptive control system having a delay harmonic synthesizer least mean square filter (hereinafter, referred to as a DXHS LMS filter) as shown in FIG. A unit 40 is provided to perform active control.
That is, the crankshaft rotation pulse and the like are extracted from the engine 11 of the automobile as the signal source by the sensor 12,
The adaptive control unit 40 determines that the frequency is the control target frequency ω, selects and outputs the control target signal, and performs amplitude compensation and phase compensation on the output signal using the filter coefficient of the DXHS LMS filter. The signal is synthesized and output. The output signal is amplified by the power amplifier 32 and input to the shaker 23, and the vibration of the shaker is suppressed to suppress the vehicle body vibration. On the other hand, an external force signal of a frequency to be controlled is detected by a pickup acceleration sensor 16 attached to the seat 15 of the vehicle M, and is used for adaptive control.

Here, an adaptive control method using a DXHS LMS filter is based on an adaptive least mean square filter (Filtered-X LM).
This is to reduce the calculation amount of the filter coefficient in S), and is performed as follows. In the adaptive control, as shown in FIG. 6, a signal s of a crankshaft rotation pulse or the like is extracted by a sensor 12 from a vibration source 51 such as an automobile engine as a signal source. ω, and selects a control target signal of the control target frequency ω and outputs it to the adaptive filter W62.
The input signal x is amplitude- and phase-compensated by the filter coefficient of the adaptive filter W62, is synthesized into a sine wave signal, and is output. The output signal y is supplied to the control target system 63 (the transfer function G), and the processed signal z is output. The processing signal z is added with an external force d that has passed through a transmission system 52 (G ′), such as vibration of the engine, and is detected by a sensor as an observed value. In adaptive control, the target of the detection value of the sensor is 0
And the difference from the target becomes the error signal e. Using the error signal e and the estimated value of the estimated transfer function 64, the adaptive filter W is sequentially updated by the digital filter 65 (DXHS LMS) as described below. Here, a signal d (target signal) having a periodicity to be controlled is represented by the following equation 1.

[0004]

D = B · exp {j (ω ^* t + φ ^* )}

Note that ω ^* represents the angular frequency of the signal d, and B and φ ^* represent the amplitude and phase of the signal d, respectively. The periodic input signal x is represented by the following equation 2, the adaptive filter W is represented by the following equation 3, and the transfer function G is represented by the following equation 4.

[0006]

X = X · exp (jωt)

[0007]

W = [a, φ]

[0008]

G = [A, Φ]

Note that ω represents the angular frequency of the input signal x, and X represents the amplitude. A and φ represent an amplitude compensation coefficient and a phase compensation coefficient. Further, A and Φ represent an amplitude transfer function and a phase transfer function. The output signal y of the adaptive filter W and the output signal z of the transfer function G are as shown in Expressions 5 and 6 below.

[0010]

Y = Xa · exp {j (ωt + φ)}

[0011]

Z = XaA.exp {j (ωt + φ + Φ)}

The angular frequency ω ^* is derived from a known input signal such as a crankshaft rotation pulse signal or an ignition pulse signal from the external sensor, and is assumed to be equal to the angular frequency ω of the output signal. Furthermore, the instantaneous mean square error J
Is represented by Equation 7 below.

[0013]

J = e ² = (z + d) ²

The updating formula of the adaptive filter is as shown in the following equation (8).

[0015]

(Equation 8)

When the gradient vector ▽ is obtained by using the above formulas 1, 6 and 7, it is expressed by the following formula 9.

[0017]

(Equation 9)

Here, since the amplitude and the phase are calculated independently of each other, the step size parameters of the amplitude and the phase are expressed as μa and μp, respectively, in the update formula for updating the filter coefficient. Also, since the true value of the transfer function is unknown, by replacing it with an estimated value (indicated by ＾), the update equation of the filter coefficient becomes
It will be like 0.

[0019]

(Equation 10)

As described above, the above algorithm does not require a convolution operation for updating a coefficient, and does not require a convolution operation for generating a reference signal. Therefore, in the case of periodic vibration or noise, When the fundamental wave and its higher-order components are to be controlled, an external harmonic signal is not required for input.

In the above adaptive control, the estimated transfer function 64
Is obtained in advance by a frequency sweep excitation or an impulse response measurement test or the like. The transfer function G is obtained by mapping an estimated value of the transfer function (G) of the control target system 64 represented by 表 記 with respect to frequency in the control program, and is referred to when the adaptive filter is updated.

[0022]

By the way, when an active control device is applied to a vehicle, the estimated transfer function is conventionally adjusted only at the time of shipment of the vehicle. When the estimated transfer function changes due to aging or the like, there is a possibility that the effect of the active control may not be properly exhibited. For example, there is a possibility that a problem such as deterioration of the noise vibration harness or divergence of the transmission characteristics of the control device may occur.

On the other hand, the estimated transfer function may be appropriately measured and updated, but when the estimated transfer function is measured, sweep vibration or the like must be performed to continuously apply vibration to the vehicle body. In addition, the occupant may feel uncomfortable, so that the measurement cannot be normally performed during the operation of the engine. Even if the estimated transfer function can be measured during operation, it is necessary to measure all frequencies within a predetermined frequency range, so that the measurement time becomes very long and the measurement data is temporarily stored. It is necessary to increase the capacity of the memory (RAM), and there is also a problem that the memory cost becomes high.

The present invention is intended to solve the above-mentioned problem, and corrects a change in an estimated transfer function due to a change in a use environment of a vehicle or a change with time without appropriately giving an occupant a feeling of discomfort. It is an object of the present invention to provide an active control device which can perform the measurement and further has an inexpensive memory for storing measurement data.

[0025]

Means for Solving the Problems and Effects of the Invention In order to achieve the above object, a structural feature of the invention according to claim 1 is that an input based on a periodic pulse signal from a vibration source of a vehicle is provided. The signal is subjected to amplitude compensation and phase compensation by a filter coefficient which is a function of an amplitude compensation coefficient and a phase compensation coefficient of an adaptive filter, and further processed by a transfer function of a controlled system of a vehicle. A digital filter based on an error resulting from the addition, and an estimated transfer function processed signal obtained by subjecting the input signal to amplitude and phase processing based on predetermined estimated transfer function data of a controlled system of the vehicle. Active control that successively updates the filter coefficients of the adaptive filter and controls the vibration of the vibrator based on the adaptive filter to actively suppress vehicle body vibration A plurality of measurement frequencies that are less and more discrete than the estimated transfer function data within a range of a predetermined frequency corresponding to the estimated transfer function data, and the signals of the plurality of measurement frequencies are provided at different times during the operation of the engine of the vehicle. The vibrator is sequentially vibrated in a short period of time, the response due to the vibration is measured, the estimated transfer function is calculated, and the estimated transfer function is estimated by comparing the calculated plurality of estimated transfer functions with predetermined estimated transfer function data. It is to estimate the change in the entire function data and update the entire estimated transfer function data based on the estimation result.

According to the first aspect of the present invention, at different times during the operation of the engine of the vehicle,
Since it is only necessary to sequentially apply vibrations to the vehicle body in a short period of time using signals of a plurality of discrete measurement frequencies, the vibration caused by the vibrations does not cause discomfort to the occupant. Further, the estimated transfer function is measured at different times during the operation of the engine, and is updated with the measured value, so that the entire estimated transfer function data can be maintained in a proper state, and the proper active Control can be performed.

Further, a measurement frequency smaller than the estimated transfer function data and discrete within a predetermined frequency range is selected,
An estimated transfer function is calculated based on the result of the excitation by the signal of this frequency, and a change in the entire estimated transfer function data is estimated by comparing the calculated estimated transfer function with predetermined estimated transfer function data, and the estimated transfer function is estimated. The entire estimated transfer function data is updated based on the result. for that reason,
According to the first aspect of the present invention, the measurement time of the estimated transfer function can be shortened, the memory capacity for temporarily storing measurement data can be reduced, and the memory cost can be reduced.

According to a second aspect of the present invention, in the active control device according to the first aspect, the plurality of measurement frequencies are made different from the frequency for which the vibration control is performed. is there. With the configuration of the second aspect of the present invention as described above, it is possible to reliably measure the estimated transfer function by vibrating at different frequencies while appropriately performing vibration control.

[0029]

DESCRIPTION OF THE PREFERRED EMBODIMENTS One embodiment of the present invention will be described below with reference to the drawings. FIG. 1 shows a DXHS LMS for removing vibration of a four-cycle gasoline engine vehicle according to the embodiment.
FIG. 2 schematically shows an active control device using a filter, and FIG. 2 is a block diagram showing an adaptive control system using a DXHS LMS filter.

The gasoline engine vehicle M has an engine mount (hereinafter referred to as an engine mount) 20 mounted on the vehicle body 10. Engine mount 2
0 has a substantially cylindrical case 21 whose both ends are sealed, as shown in FIG. The case 21 has an annular convex portion 21a bulging coaxially outward at a substantially middle position in the axial direction. A substantially disk-shaped anti-vibration rubber 22 is coaxially fixed on the inner wall side of the annular convex portion 21a along the circumferential direction.
The anti-vibration rubber 22 has an axial cross-sectional shape projecting toward the one end side (upper end in the figure) of the case 21 in a mountain shape, and a substantially inverted conical fixing bracket 24 is coaxially fixed to the top side of the mountain shape. I have. An annular stopper portion 22a is formed at the peripheral edge of the flat surface (the upper end surface in the figure) of the fixing bracket 24 so that the vibration-proof rubber 22 is wrapped around and protrudes toward one end of the case 21.
A fixed shaft 25 is coaxially attached to an axial center position of the flat surface of the fixing bracket 24, and a distal end thereof protrudes from a through hole 21 b provided at a center position on one end side of the case 21.
The fixed shaft 25 has a screw hole at an axial center position.
An actuator 23 which is a vibrator for controlling the dynamic displacement of the engine is provided on the opposite side (lower side in the figure) of the vibration isolating rubber 22 in the case 21. A fixed shaft 26 having a thread groove is coaxially provided outward at a center position of the other end side (the lower end in the figure) of the case 21.

The engine mount 20 is fixed to the vehicle body 10 by a fixed shaft 26.
Is attached, the engine 11 is elastically supported. A rotation pulse sensor 12 is provided on a crankshaft of the engine 11.
Outputs a crankshaft rotation pulse signal, and based on this, a control unit 31 described later determines a fundamental frequency of the output signal. Further, a pickup acceleration sensor 14 for detecting a rotation speed (frequency) to be controlled is attached to the seat 13 of the automobile M.

The electric control device 30 for controlling the vibration removal includes:
A control unit 31 including a microcomputer is provided, and a part of the control unit 31 includes the adaptive control unit 40 described above.
Further, the adaptive control unit 40 stores a data table RAM 41 storing data of the estimated transfer function. The control unit 31 executes the “vibration removal control program” shown in FIG. The rotation pulse sensor 12 and the pickup acceleration sensor 14 are connected to the input side of the control unit 31. The actuator 23 of the engine mount 20 is connected to the output side of the control unit 31 via a power amplifier 32.

The present embodiment is directed to an automobile equipped with a four-cycle four-cylinder engine, and the vibration frequency range of the rotation secondary component, which is a problem, is 20 to 200 Hz between 600 and 6000 rpm. is there. In this frequency range, for example, 21 discrete measurement frequencies f _{1 to} f ₂₁ are selected at intervals of 10 Hz, and excitation is performed in a spot for one period at predetermined intervals, for example, intervals of 10 minutes for each measurement frequency, The transfer function is measured. The predetermined interval may be constant or different. The time required for the measurement is a short time such that the occupant does not feel the excitation performed in a spot manner, and is a time standard of 0.5 second or less. Further, the measurement frequencies f ₁ to
For f _21, the frequency different from the frequency at which adaptive control is performed is adapted to be selected. Thereby, appropriate excitation can be performed without disturbing the execution of the adaptive control. The selection of the frequency range, the selection of the measurement interval, and the relationship with the frequency of the adaptive control are performed under the control of the control unit 31.

Further, the control unit 31 stores transfer function data obtained by oscillating the actuator 23 at the ₂₁ measurement frequencies f _{1 to} f ₂₁ with data of the estimated transfer function stored in the data table RAM 41 in advance. A control is performed to compare and estimate a change in the estimated transfer function based on the comparison, and to update the data of the entire estimated transfer function stored in the data table RAM 41 based on the estimated data. Here, as the estimation method, there is a method of simply adding the average value of the rate of change of each transfer function measurement data, and a method of obtaining a correlation coefficient from the measurement data and correcting the data based on the correlation coefficient is also possible. Yes, and it is also possible to estimate data changes by using various data analysis methods.

Next, the operation of the embodiment configured as described above will be described. The control unit 31 starts execution of the “vibration removal control program” in step 70 shown in FIG. 4, and in step 71, the measurement frequency fx (x = 1 to 2)
1) is selected, and the number x is initialized to “1”. In step 72, the measurement time interval T is selected, and the elapse of time is counted in the control unit 31. Next, it is determined whether or not the engine is in an operating state. When the engine is in an operating state (step 73), adaptive control is performed according to the adaptive control system shown in FIG. 2, and vibration elimination control of engine vibration is performed (step 73). 74). Next, it is determined whether or not the measurement time of the transfer function has come (step 75). When the measurement time has come, the measurement of the transfer function is started. That is, the frequency f _1, the spot to excitation signal is output (step 76), pressure of the actuator 23 vibration is performed, the vibration caused by excitation is input to the control unit 31 by the pickup acceleration sensor 14, the result Based on this, the estimated transfer function value Dx (here, D1) is calculated (step 7).
7). The calculated value Dx of the estimated transfer function data is temporarily stored in the data table RAM 41, and the number of times of measurement x
Is increased by "1" (steps 78 and 79). Here, the measurement time of the estimated transfer function is as short as 0.5 seconds or less as described above, and because the vibration is spot-like, the vibration is not noticed by the occupant. It does not give any discomfort.

Next, it is determined whether or not the measurement at the measurement frequencies f _{1 to} f ₂₁ has been completed (step 80). Here, since the measurement has not been completed, the program returns to step 75, and the processing of the following steps is performed. When the measurement at the measurement frequency f ₁ ~f ₂₁ terminates all the program is transferred to step 81, based on the measurement data for each measurement frequency, the data table RAM
The change of the entire estimated transfer function data is estimated based on the comparison with the estimated transfer function data stored in 41. Based on the estimated data, the stored data of the entire estimated transfer function is updated (step 82). Thereafter, the program ends at step 83 and a new execution is started at step 70.

As described above, according to the above embodiment, the measurement time of the estimated transfer function is shortened, and the data table RA for temporarily storing the measurement data is used.
The capacity of M41 can be reduced, and the memory cost of the control unit 31 can be reduced.

In each of the above embodiments, the rotation pulse signal of the engine is used.
From the vehicle position detection signals such as shift position and water temperature,
By obtaining the filter coefficients, it is also possible to perform adaptive control. In each of the above embodiments, the DXHS LMS filter is used as the adaptive filter.
Another adaptive filter such as an ed-X LMS filter may be used.

[Brief description of the drawings]

FIG. 1 is a schematic diagram schematically showing an active control device for removing vibration of a four-cycle gasoline engine vehicle according to an embodiment of the present invention.

FIG. 2 is a block diagram schematically showing an adaptive control system.

FIG. 3 is a partial cross-sectional view showing an engine mount with an actuator mounted on a vehicle.

FIG. 4 is a flowchart illustrating a “vibration removal control program” executed by a control unit.

FIG. 5 is a schematic diagram schematically showing a part of a vehicle to which a conventional active control device is applied.

FIG. 6 is a block diagram schematically showing a conventional adaptive control system.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 10 ... Body, 11 ... Engine, 12 ... Rotation pulse sensor, 14 ... Pickup acceleration sensor, 20 ... Engine mount with an actuator, 21 ... Case, 22 ... Anti-vibration rubber, 23 ... Actuator, 30 ... Electric control device, 3
DESCRIPTION OF SYMBOLS 1 ... Control part, 32 ... Power amplifier, 40 ... Adaptive control part,
41: Data table RAM, 51: Vibration source, 52
... signal transmission system, 61 ... frequency determination unit, 62 ... adaptive filter W, 63 ... controlled object system (transfer function G), 64 ... controlled object system (estimated transfer function), 65 ... digital filter (DXHS)
LMS).

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat ゛ (Reference) G05B 23/02 G05B 23/02 F G05D 19/02 G05D 19/02 D // G05B 15/02 G05B 15 / 02 PF term (Reference) 3D035 CA05 CA27 CA35 3J048 AA10 AB15 AC07 AD03 CB19 CB24 EA01 5H004 GA14 GA15 GA35 GB12 HA12 HB08 JB03 KA32 KB21 KC12 KC44 MA06 MA11 5H215 AA10 BB01 CC07 CX04 GG09 GG17 AE17 5

Claims (2)

[Claims] An input signal based on a periodic pulse signal from a vibration source of a vehicle is subjected to amplitude compensation and phase compensation by a filter coefficient which is a function of an amplitude compensation coefficient and a phase compensation coefficient of an adaptive filter. After processing using the transfer function of the controlled system, the processing signal based on the transfer function and the external force from the vibration source are added, and an error resulting from the addition and a predetermined estimation of the controlled system of the vehicle are performed. A digital filter sequentially updates filter coefficients of the adaptive filter based on an estimated transfer function processed signal obtained by subjecting the input signal to amplitude and phase processing using transfer function data, and performs excitation control of a vibrator based on the adaptive filter. The active control device that actively suppresses the vehicle body vibration by performing the estimation in a range of a predetermined frequency corresponding to the estimated transfer function data A plurality of measurement frequencies less and discrete than the transfer function data are selected, and at different times during the operation of the engine of the vehicle, the vibrator is sequentially vibrated in a short time by the signals of the plurality of measurement frequencies. A response is measured to calculate an estimated transfer function, a change in the entire estimated transfer function data is estimated by comparing the calculated plurality of estimated transfer functions with predetermined estimated transfer function data, and based on the estimated result, An active control device, wherein the entirety of the estimated transfer function data is updated. 2. The active control device according to claim 1, wherein the plurality of measurement frequencies are different from the frequency at which the excitation control is being performed.