JP3281120B2 - Vehicle vibration reduction device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a vibration reducing device for a vehicle in which vibration, that is, noise of the vehicle is reduced by an interference effect using vibration for reduction.

[0002]

2. Description of the Related Art In a vehicle, in particular, an automobile or the like in which noise caused by an engine, that is, first vibration is a problem, a reducing vibration, that is, second vibration is generated from a speaker or the like, and the first vibration and second vibration are generated. It has been proposed to reduce the first vibration by interference with the first vibration.

[0003] In this type of vibration reduction apparatus, as shown in Japanese Patent Application Publication No. 1-501344, a reference signal generator for extracting a signal from a vibration source, that is, a signal corresponding to the first vibration, as a reference signal. A microphone for picking up vibration in a predetermined space where noise caused by the first vibration is a problem, a speaker for generating a second vibration toward the predetermined space, and a second vibration for outputting from the speaker. And an algorithm operation device for sequentially optimizing the filter coefficients of the filter. That is, the adaptive digital filter adjusts the gain, phase, and the like of the reference signal according to the reference signal to generate the second vibration, while reducing the filter coefficient of the adaptive digital filter so that the vibration detected by the microphone is reduced. Are sequentially optimized by the algorithm operation device. In general, a least-squares method is used as an algorithm for optimization.

The above-described vibration reducing device has the advantage that vibration can be reduced widely in response to various vibrations, but the amount of calculation is extremely large. , A high-end arithmetic unit is required. In particular, as the number of speakers and microphones increases, the amount of calculation increases in series.

[0005] In view of the above, the present applicant has taken into consideration that in vehicles, the first vibration to be canceled is generally periodic, such as vibration caused by rotation of the engine. As a result, a vibration reduction device for a vehicle which can extremely reduce the amount of calculation for generating the vibration for reduction and which does not require a sophisticated arithmetic device has been developed.

That is, a cycle detecting means for detecting a cycle of the first vibration generated due to the rotation of the engine;
A second vibration source (reducing vibration generating source) for outputting a second vibration (reducing vibration) for reducing the vibration energy of the vibration, for example, a speaker, and a vibration for detecting a vibration of a place such as a vehicle room to reduce the vibration. Detecting means such as a microphone, setting means for setting the vibration energy of the second vibration output from the second vibration source for each cycle detected by the cycle detecting means, and setting the output of the setting means to the vibration detecting means and the vibration. Detection means and second
Correction means for correcting based on the transfer characteristics between the vibration source and the vibration source.

[0007] With this configuration, although it is not possible to cope with sporadic or sudden vibrations, the second vibration waveform generation processing and the vibration picked up by the microphone are performed based on the cycle detected by the cycle detecting means. About processing 1
Since the calculation for the optimization of the vibration waveform of the second vibration can be performed very easily, the periodic vibration can be sufficiently reduced without using a sophisticated arithmetic unit. Become.

[0008]

However, in the above-described apparatus for reducing periodic vibration, the second vibration, that is, the reduction of the second vibration, is required when the control of the vibration reduction is once stopped and the control of the vibration reduction is started again. Since the vibration for use is newly optimized from the beginning, it is difficult to sufficiently reduce the vibration until the optimization is sufficiently performed.

SUMMARY OF THE INVENTION The present invention has been made in view of the above circumstances, and is intended to correct or optimize the reducing vibration for each period of the periodic vibration to be reduced. It is an object of the present invention to provide a vehicle vibration reduction device capable of sufficiently obtaining a vibration reduction effect.

[0010]

Means for Solving the Problems To achieve the above object, the present invention has the following configuration. That is, a vehicle vibration control device for reducing a periodic vibration generated by a first vibration source in a predetermined space of the vehicle, comprising: a period detecting unit configured to detect a period of the first vibration; A second vibration source for outputting a second vibration for reducing vibration energy, vibration detecting means for detecting vibration in the predetermined space, and information corresponding to a waveform signal for one cycle of the second vibration, that is, n pieces of information. For the output data, which is an n-dimensional vector having the waveform amplitude value as a component, a multiplication value of the n with a sampling period at the time series conversion described later is detected by the period detecting means. Setting means for setting to be the same as
The output data set by the setting means in a previous control cycle is corrected for each cycle based on an output of the vibration detection means and a transfer characteristic between the vibration detection means and the second vibration source. A correction unit, and arranging the components of the output data corrected by the correction unit in a sampling cycle, thereby performing time-series conversion into a waveform signal of a second vibration, and converting the waveform signal obtained by the conversion into the second signal. (2) output means for outputting from the vibration source, control means for starting the operation of the correction means and the output means when a predetermined control start condition is satisfied, and control which has been performed last time at the start of control by the control means. And initial value setting means for setting output data of the second vibration at the end of the vibration reduction control as an initial value at the start of the control.

Preferred embodiments of the present invention based on the above configuration are as described in claims 2 and 3 in the claims.

[0012]

【The invention's effect】

According to the first aspect of the present invention, at the time of starting the control of the vibration reduction, the output data at the end of the previous control of the vibration reduction is used as an initial value, so that it is completely new. As compared with the case where the vibration for reduction is optimized, the effect of vibration reduction can be obtained earlier.

[0014] With the configuration as described in claim 2, the difference between the engine speed at the end of the previous vibration reduction control and the engine speed at the start of the new vibration reduction control is calculated. When the value is too large, that is, when the suitability as the initial value is reduced, the setting of the initial value is prohibited, so that the adverse effect of the setting of the initial value can be avoided.

According to the configuration described in claim 3, since the output is started from the timing when the amplitude becomes 0 among the set initial values, the output is suddenly started from the timing when the amplitude is large. This is preferable in preventing a situation where the user is likely to feel that abnormal noise is likely to occur.

According to the fourth aspect of the present invention, the output gain of the vibration for reduction is gradually increased, so that the vibration change between before and after the start of the control is smooth. This is particularly preferable for preventing a situation in which the output is started at a timing when the amplitude of the vibration for reduction suddenly is large and the user feels that abnormal noise is generated.

[0017]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments of the present invention will be described below with reference to the accompanying drawings. In FIG. 1, an automobile 1 is a four-seater passenger car having a driver's seat 3, a passenger seat 4, and left and right rear seats 5 and 6 in a cabin 2. An in-line four-cylinder gasoline engine 8 is mounted on an engine room 7 formed at the front of the vehicle body, and its ignition coil is indicated by reference numeral 9.

The engine 8 is a noise source that generates a periodic vibration according to the engine speed, that is, a first vibration source. The cabin 2 is a predetermined space in which vibration of the engine 8 should be reduced. For this purpose, five speakers 11 and eight microphones 12 are installed in the cabin 2 as a predetermined space. The speaker 11 is a second vibration source that generates a second vibration for reducing engine noise in the vehicle compartment, that is, a reduction vibration generation source. And microphone 1
Reference numeral 2 denotes a vibration detecting unit that detects actual vibration of the passenger compartment. In the embodiment, the speaker 11 is also used for audio sources such as a cassette deck and a tuner, but may be provided exclusively for reducing vibration.

The automobile 1 has a control unit U mounted thereon using a microcomputer. The input / output relationship for the control unit U is shown in FIG.
The control unit U has a control unit 20 including a CPU. The control unit 20 receives a signal from the primary coil of the ignition coil 9, that is, an ignition pulse signal corresponding to the engine speed via a waveform shaping circuit 21 and a cycle calculation circuit 22, and receives a signal from each microphone 12. , An amplifier 23, a low-pass filter 24, and an A / D converter 25. The output signal from the control unit 20 is D
The signal is output to the speaker 11 via the / A converter 26, the low-pass filter 27, and the amplifier 28.

The control unit 20 optimizes the second vibration to be output from the speaker 11 so that the vibration detected by the microphone 12 is reduced. Hereinafter, the generation of the second vibration by the control unit 20 will be described. First, the basic point of the generation of the second vibration will be described.

Generation of Second Vibration (Basic) FIG. 3 is a block diagram showing the control unit 20.
For simplicity of description, the case where one speaker 11 and one microphone 12 are used is shown.

The control unit 20 adjusts the cycle of the vector y of the speaker input signal y to be output to the speaker 11 based on the result input from the cycle measuring circuit 22 (step 1,
The following step is abbreviated as S), and a built-in processor converts the matrix h of the impulse response h which is the transfer characteristic between the microphone 12 and the speaker 2 into a time series h (S).
2).

Next, the control unit 20 is a processor that sequentially optimizes the vector y based on the time series h of the impulse response h and the microphone output signal e input from the microphone 12 (S
3) After that, the vector y is converted into a time series y to be a speaker input signal y (S4) and output to the speaker 11.

The speaker 11 receives the input signal y
Is reproduced as anti-noise Z. On the other hand, the microphone 12
The noise d and the anti-noise Z cancel each other out, and the noise whose vibration energy is reduced is detected, and the result is output as a digital microphone output signal e to a processor built in the control unit 20. Hereinafter, the processor again executes the above step 3
And step 4 are repeated to obtain the speaker input signal y
Are sequentially optimized, and the vector y of the speaker input signal y is set so that the value of the microphone output signal e finally becomes zero.

Next, the calculation of the algorithm of the above steps performed by the control unit 20 will be described below.

First, the sampling period of the microphone output signal e of the microphone 12 by the control unit 20 is set to Δt. Assuming that the impulse response h, which is the transfer characteristic between the microphone 12 and the speaker 11, converges to 0 within a finite time J △ t, and the value of the impulse response h after the elapse of j △ t after the impulse input is given Let h _j be the noise d, which is the first vibration generated from the engine 8, the anti-noise Z, which is the second vibration generated from the speaker 11 when the speaker input signal y is given, and the noise d at that time. The relationship between the k-th sample value e (k) of the microphone output signal e at time k can be expressed by the following equation (1).

E (k) = d (k) + Z (k) = d (k) + matrix h ^T · matrix y (k) (1) where matrix h = [h ₀ h ₁ h ₂ ... H _J-1 ] ^T matrix y (k) = [y (k) y (k-1) y (k-2).
(K-J + 1)] ^T d (k): component of noise d included in e (k) Z (k): component of anti-noise Z included in e (k) y (k) : K-th sample value of speaker input signal y Therefore, Z (k) in equation (1) is represented by the following equation (2).

[0028]

(Equation 1)

Since the noise d is a periodic noise having a certain period N △ t, the anti-noise Z for reducing the vibration energy of the noise d, the speaker input signal y, and the same period as the noise d It must be a periodic oscillation and a periodic signal with N △ t.

Therefore, the following equation (3) holds for the speaker input signal y. y (k) = y (K-qN) = y (k) y (k-1) = y (k-qN-1) = y (k + N-1) y (k-2) = y (k -qN-2) = y (k + N-2) (3) ... y (k-N + 1) = y (k- (q + 1) N + 1) = y (k + 1) where q = 0, 1, 2,... Therefore, equation (1) is expressed as follows: e (k) = d (k) + vector h ^T · time series y (k ) (4) where y (k) = [y (K) y (K + N-1) y (K + N-2)
・ ・ Y (K + 1)] ^T

[0031]

(Equation 2)

Here, Q is the minimum value of the integer q satisfying J ≦ (q + 1) N.

Next, the K + i-th sample value e of the microphone output signal e at the time k + i after the time i has further elapsed from the time k.
(K + i) (where i = 1, 2,...) Is given by the following equation (5)
Can be represented by

E (k + i) = d (k + i) + vector h T · time series y (k + i) = d (k + i) + time series h (i) T · time series y (k ) ..... (5) where the time series y (k + i) = [ y (k + i) 'y (k + i' -1) y (k + N-1) y (k + N -2) ············ y (k + i ' +1)] T time series h (i) = [bar h i ' bar h i + 1 ' ···· bar h
N + 1 bar -h 0 Ba -h 1 · · · · bar -h i '-1] T Note that, i' is an integer remainder of the division of the i in N.

By the way, in the equation (5), k merely represents an arbitrary initial point of the microphone input signal e. Therefore, when k = 0 and i is replaced with k again, the following equation (6) is obtained.

E (k) = d (k) + time series h (k) ^T · time series y (0) = d (k) + time series h (k) ^T · vector y where vector y = [y (0) y (N-1) y (N-2)... Y (1)] ^T = [y ₀ y _N-1 y _N-2 ... Y ₁ ] ^T where the next evaluation Introduce a function. F = E [e (k) ² ] = E [d (k) + time series h (k) ^T · vector y] = E [d (k) ² ] +2 vectors y ^T · E [d (k) · when the series h (k)] + vector y ^T · E [time series h (k) · time series h (k) ^T] vector y ······ (7) However, E [] is the expected value (E is an expected operator). From Expression (7), the gradient of the evaluation function with respect to the vector y is given by the following Expression (8). ∂F / ∂ vector y = 2E [d (k) · time series h (k)] + 2E [time series h (k) · time series h (k) ^T ] vector y = 2E [time series h (k) { d (k) + time series h (k) ^T vector y｝] = 2E [time series h (k) · e (k)] (8) where E [time series h (k) If the time series h (k) · e (K) is used as the instantaneous estimated value of [e (K)], the speed having the period N △ t (ie, the number of elements N) that gives the minimum value of F is obtained. The value of the vector y, which is the output signal vector, can be optimized by repeatedly calculating the following recurrence formula (9) based on the steepest descent method.

Vector y (K + 1) = Vector y (k) −μ · e (k) · Time Series h (k) (9) where μ / 2 is a convergence coefficient.

The recurrence formula (9) obtained in this manner corrects the setting of the vibration energy of the anti-noise for reducing the vibration energy of the noise by the processor as the data processing device built in the control unit 20. In this case, it is replaced with a simpler algorithm as shown below.

First, a pair of the speaker 11 and the microphone 1
When 2 is used, recurrence equation (9) is replaced by the following equation (10). y _{(k−j + QN)} ^′ (k + 1) = y _{(k−j + QN)} ^′ · (k) −μ · e (k) · h _j (10) At this time, the processor In k, for example, the following four operation procedures are performed.

Operation 1: The speaker input signal y _k ^′ (k) is output to the speaker 11. Operation 2: A microphone output signal e (K) is input from the microphone 12. Operation 3: Engine 22 input from cycle measurement circuit 22
The integer value closest to a value obtained by multiplying the rotation cycle of Ord / Δt or 1 / (Ord · Δt) is set to N. Operation 4: The recurrence formula (10) is calculated for j = 0, 1, 2,..., J-1. Here, k ′ and (k−j + QN) ′ are respectively k (k−
j + QN) is an integer remainder when N is divided by N, and Ord is an arbitrary constant for setting the lowest order of the noise to be reduced with respect to the engine speed.

Next, when a plurality of speakers 11... And microphones 12 are used, for example, based on the steepest descent method,

[0042]

(Equation 3)

As an instantaneous estimated value of

[0044]

(Equation 4)

Using, the evaluation function

[0046]

(Equation 5)

The optimum value of the vector y ₁ , which is the first speaker output signal vector for minimizing the following equation, is represented by the following recurrence equation (11).
Is calculated by iterative calculation.

[0048]

(Equation 6)

[0049] However, y _lk ^': first spin at time k - Ka input signal e _m: m-th microphone output signal h _LMJ: first spin - force between-the m microphone impulse response j △ t time after Value L: Number of speakers M: Number of microphones J: Integer value indicating that the impulse response between all the speakers and microphones converges to 0 within a finite time Δt Also, the vector _yl = [y _{l 0 yl N-1 yl N-2} ... y
_{l 1} ] ^T time series h _lm (k) = [bar h _{lm k '} bar h _{lm k' + 1} ...
Bar h _{lm N + 1} Bar h _{lm 0} Bar h _{lm 1} ... Bar h _lm
k'-1] ^T In addition, bus _{-h lm 0 = h lm 0 +} h lm N + ···· h lm QN server _{-h lm 1 = h lm 1 +} h lm N + 1 + ··· h lm QN + ₁ ... ... ... ... server _{-h lm j-QN-1 =} h lm j-QN-1 + h lm j- (Q-1) N-1 + ··· + h _{lm j-1} bar h _{lm j-QN} = h _{lm j-QN} + h _{lm j- (Q-1) N} + ・ ・ ・ +0 ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・Bar _{lmN -1} = _{hlmN -1} + _{hlm2N -1} +... +0 l = 1, 2,..., Lm = 1, 2,. Formula (9) is replaced by the following formula (12).

[0050]

(Equation 7)

At this time, the processor performs, for example, the following four operation procedures at time k.

Operation 11: speaker input signal y _1k ^′ (k),
^{_{y 2k '(k), ····}} , y lk' (k) , respectively first spin - force, the second spin - outputs to mosquitoes - mosquitoes, ..., a L spin. Operation 12: microphone output signals e ₁ (k), e ₂ (k),..., E _M (k)
Are input from the first microphone, the second microphone,..., The Mth microphone, respectively. Operation 13: the engine 2 input from the cycle measurement circuit 22
An integer value closest to a value obtained by multiplying the rotation cycle of 2 by Ord / △ t or 1 / (Ord △ Δt) is defined as N. Operation 14: 1 = 1, 2,... L and j = 0,
The recurrence formula (12) is calculated for 1, 2,..., J-1. Also, the plurality of speakers 11 ... and the microphones 12 ...
・ ・ When using

[0053]

(Equation 8)

As the instantaneous estimated value of α, time series h _1k ^′ (k)
・ Using e _k ^' (k), the evaluation function is calculated based on the steepest descent method.

[0055]

(Equation 9)

The optimum value of the vector y ₁ , which is the first speaker output signal vector for minimizing the following equation, is expressed by the following recurrence equation (13).
Is calculated by iterative calculation. Vector y ₁ (k + ₁₎ = vector _{y 1 (k) -μ · α} · time series ^{_{h 1k "(k) · e}} k" (k) ···· (13) However, k "is, the k M Is a value obtained by adding 1 to the integer remainder obtained by dividing by 1. The recurrence formula (13) can be calculated in a shorter time than the recurrence formula (11).

Therefore, the recurrence equation (9) is replaced by the following equation (14). _{y 1 (k-J + QN} ) '(k + 1) = y 1 (K-j + QN)' (k) -μ · α · e k (k) · h 1k "j ····· ( 14) At this time, the processor performs, for example, the following four operation procedures at the time.

Operation 21: speaker input signal y _1k ^′ (k), y
_2k ^′ (k),..., Y _Lk ^′ (k)
, The second speaker,...,..., The L-th speaker. Operation 22: The microphone output signal e _k ^" (k) is input from the k-th microphone. Operation 23: the engine 2 input from the cycle measurement circuit 22
An integer value closest to a value obtained by multiplying the rotation cycle of 2 by Ord / Δt or 1 / (Ord · Δt) is defined as N. Operation 24: 1 = 1, 2,..., L and j = 0,
The recurrence formula (14) is calculated for 1, 2,..., J-1. Therefore, the operation of the above algorithm is the recurrence formula (9),
(11) and (13) or the recurrence formulas (10), (12) and (14), which are simplified versions of these recurrence formulas, need only be iteratively calculated, so that the calculation time for speaker input control is reduced. It is possible to do.

Control at the Start of Vibration Reduction Control Next, with reference to FIG. 4 and subsequent drawings, a description will be given of the control of the above-described vibration reduction, that is, the specific control at the start of the ANC control. (1) Overall Overview (FIGS. 4 to 7) First, in FIG. 4, in relation to the ANC control unit 20 and the cycle (engine speed) measurement unit 22, each functional unit 5
1 to 54, that is, ON / OFF determination unit 51 of ANC control
, A memory 52, an initial data correction unit 53, and a data adjustment unit 54 at the start of output.

The determination unit 51 determines whether or not to execute the ANC control. In the embodiment, when the IG pulse is not continuously input for a predetermined time (corresponding to the determination of engine stop), or It is determined that the ANC control is stopped or turned off when the fluctuation of the engine speed, that is, the fluctuation of the rotation cycle is large, and that the ANC control is executed or turned on at other times. Then, based on the determination result of ON and OFF of the ANC control, each part 20,
The control of 52 to 54 is performed as described later. The memory 52 stores waveform data of the vibration for reduction at the end of the ANC control, that is, output data.

The correction unit 53 converts the waveform data stored in the memory, that is, the output data, into the engine speed at the time when the stored output data is generated (previous A
The adjustment is performed based on the difference between the engine speed at the end of the NC control) and the engine speed at the time when the ANC control is newly started this time. More specifically, the data length (data number) of the output data stored in the memory 52 is adjusted according to the difference in the engine speed as described later. An example of adjusting this data length is schematically shown in FIG. 5. In FIG. 5, the old data is the output data stored in the memory 52, and the new data is the new data. The one shown as corresponds to the engine speed when the ANC control is newly started this time.
In the data length adjustment shown in FIG. 5, new data is obtained by expanding and contracting the vibration waveform of the old data as much as possible without breaking it as much as possible.

At the start of output, the data adjustment unit 54 applies the initial value corrected by the initial data correction unit 53 to the ANC control unit 20.
This is to prevent the output from being performed at a timing when the amplitude is suddenly large when output from. For this reason, the data adjustment unit 54 is provided with the ANC control unit 20 as shown in FIG.
The output is started after waiting for the timing at which the amplitude becomes 0 or almost 0 among the outputs from, or the output gain is initially set to 0 and gradually increased as shown in FIG.

(2) Details of the Judgment Unit 51 (FIG. 8) FIG. 8 is a flow chart showing the control contents of the judgment unit 51. First, in Z (step-the same applies hereinafter) 1, as described above, By checking the input state of the IG pulse and the magnitude of the fluctuation of the engine speed, it is determined whether or not to execute the ANC control. In Z2, it is determined whether or not the determination result in Z1 is ON. If the determination in Z2 is NO, it is determined in Z3 whether or not the ANC control is OFF. When the determination in Z3 is NO, that is, when the ANC control is currently ON, the output data (corresponding to the old data shown in FIG. 5) at that time is stored in the memory 52. , A5 in Z5
A command to turn off the control is output.

If the determination in Z2 is YES, Z6
In, it is determined whether or not the ANC control is currently ON. When the determination in Z6 is NO, that is, when the ANC control is newly started this time, after the initial data is corrected by the initial data correction unit 53 in Z7, the ANC control is turned on in Z8. Output the command to be executed. If the determination in Z3 is YES, or if the determination in Z6 is YES, the operation is returned as it is.

(3) Details of the initial data correction unit 53 (FIG. 5,
9 to 14) FIG. 9 is a flowchart showing the control contents of the initial data correction unit 53. In Q (step-the same applies hereinafter) 1 in FIG. 9, the output data stored in the memory 52 is output.
The data number n _{0 of the data} is read. Next, at Q2, the current engine speed r is read. After this, Q
In 3, according to the equations shown here, de corresponding to the current engine speed r - motor speed n ₁ is calculated. In this equation, "sf" is the sampling frequency (Hz), and "int" means that the calculation result is an integer rounded off.

In Q4, it is determined whether or not the data numbers n ₀ and n ₁ match. If the determination in Q4 is NO, the data length correction is performed in Q5 as described later, and then the process proceeds to Q6. YES in Q4 discrimination
In the case of, the process shifts to Q6 without passing through Q5. In Q6, the waveform data corrected or not corrected in Q5 is transferred to the ANC control unit 20 as an initial value.

An example of the data length correction in Q5 will be described with reference to FIGS. First, the contents of the data length correction performed in Q5 are schematically shown in FIG. FIG. 5A shows the previous vibration waveform, and the number of data values is six. Fig. 5 (3)
This shows the vibration waveform to be obtained by expanding and contracting the waveform,
The case where the data value is eight is shown. In FIG. 5, first, as shown in FIG. 5 (2), a temporary vibration waveform is formed. This provisional vibration waveform is set to have the same data length as the data length of the previous vibration waveform, and the new data value number is set on this provisional data length. A sampling cycle is set according to certain eight data values. In the case of this embodiment, the tentative sampling period at the tentative data length (temporary vibration waveform) is the basic, that is, 6/8 of the sampling period at the previous data length.

Then, on the temporary data length, the data value of the previous vibration waveform is plotted at each temporary sampling timing. By returning the provisional vibration waveform obtained in this way to the original basic sampling period (outputting the provisional vibration waveform for each basic sampling period), the waveform shown in FIG. An elongated vibration waveform is obtained. It is to be noted that the same operation is performed when the waveform is reduced, but in this case, the temporary sampling period is longer than the basic sampling period.

Assuming the above, the contents of Q5 are shown in FIG. First, in Q11, i is 1
After that, in Q12, j is set according to the equation shown here. Next, in Q13, k
Is determined according to the equation shown here, where "in
The meaning of "t" means that it should be a rounded integer. For example, as shown in FIG. 4, n ₀ is 6, n ₁
Is 8, the value in parentheses enclosed by "int" is initially 0.75, so k is set to 8.

After Q13, in Q14, it is determined whether j = k. If the determination in Q14 is YES, the process proceeds to Q18 after y (j) is set as y '(i) in Q15. When NO is determined in the determination of Q14, after jk is set as j,
After calculating y ′ (i) described later in Q17, the process shifts to Q18. The processing of Q15 is a case where the previous data value exists just at the phase position of j.
The processing of No. 6 is a case where the previous data value does not exist at the phase position of j.

In Q18, after i is set to i + 1, Q19
In, it is determined whether or not i is equal to n ₁ corresponding to the current data number. Initially, the determination in Q19 is NO, so the process returns to Q12, the above-described processing is repeated, and the interpolation is continued.

If the determination in Q19 is YES, Q
After setting i to 0 at 20, at Q21,
After changing y ′ (i) to y (i), i + 1 in Q22
There is set as i, and, in Q23, i is judged whether greater than n ₁ is initially N in this determination
The result is set to O, and the processing after Q21 is repeated. And Q
When the result of the determination in step 23 is YES, the interpolation is terminated, and the return is made.

The processing of Q12 to Q19 described above is the same as that of FIG.
This is the process of creating temporary data shown in (2), and the process after Q20 is the process of changing this temporary data to new data shown in FIG. 5 (3).

FIG. 11 shows the contents of Q17.
That is, in Q25 of FIG. 11, it is determined whether or not k + 1 is greater than n ₀ , and NO is determined in the determination of Q25.
In Q26, to perform the primary interpolation, the arithmetic mean of the values before and after the phase position of i is set as y '(i). When the determination in Q25 is YES, the phase position of k is the last and there is no subsequent phase position, but the subsequent phase positions are equal to those of the first phase position. Therefore, the arithmetic mean of the value of the immediately preceding phase position and the value of the first phase position is y ′ (i)
Is set as The meaning of the arithmetic mean indicated by Q26 or Q27, that is, the content of the primary interpolation is schematically shown in FIG.

FIG. 13 shows a case where the entire vibration waveform is expanded and contracted by analog processing. That is,
Considering that the previous data passes through the D / A converter 26 for the speaker 11 and the low-pass filter 27,
The signal after passing through the pass filter 27 is set to return to the control unit 20 again through the A / D converter 41. The sampling cycle of the A / D converter 41 is set by the frequency dividing circuit 42, and the sampling cycle of the frequency dividing circuit 42 is set to the previous data by the sampling adjuster 42 which receives a command signal from the control unit 20. The value is set to a value corresponding to the ratio between the number and the current data number. In the case of the present embodiment, the whole of the vibration waveform can be expanded and contracted by the very general methods of D / A conversion and A / D conversion, and the speaker 11 is used as the D / A converter. By doing so, the structure becomes simpler and the cost is more advantageous than when a D / A converter for expanding and contracting the vibration waveform is separately provided for exclusive use.

(4) Prohibition of Initial Value Setting When the engine speed at the end of the previous ANC control is greatly different from the engine speed at the time when the ANC control is newly started, the initial value is stored in the memory 52 described above. It is preferable to prohibit the setting of the initial value using the output data which is present, and a control example for this is shown in FIG. The flowchart shown in FIG. 14 shows only a main part thereof, and is a partial modification of FIG.

That is, after Q3 in FIG. 9, in Q31 in FIG. 14, the absolute value of the difference between the data numbers n ₀ and n ₁ is calculated as the deviation d. And in Q32,
It is determined whether the deviation d is equal to or greater than a predetermined value. This Q
If the determination at 32 is NO, it is assumed that there is no problem even if the output data stored in the memory 52 is used.
The processing from Q4 onward in FIG. 9 is performed (there is an initial value setting).

If the determination in Q32 is NO, in Q33, the data values of the output data stored in the memory 52 are corrected to be all zeros, and then the flow shifts to Q6 in FIG. . The process of Q33 is equivalent to correcting the amplitude of each phase of the output data stored in the memory 52 to all zeros, and is substantially the same as the state without initial value setting. In FIG. 14, the difference in engine speed is determined based on the difference between the data numbers n ₀ and n ₁ .
The difference in engine speed may be directly observed (AN
The engine speed at the end of the C control is stored).

(5) Details of output data adjustment (FIG. 15, FIG. 1)
6) FIG. 15 shows an example of the control contents of the output data adjusting section 54. As shown in FIG. 6, the control contents for starting the output after waiting for the timing when the amplitude becomes 0 are shown. This figure 1
In 5, first, in Q 41, it is determined whether or not the determination result of the determination section 51 is ON. If the determination in Q41 is NO, the output adjustment is unnecessary. In this case, the flag is reset to 0 in Q49, and then the return is made.

If the determination in Q41 is YES, in Q42, a signal from the ANC control unit 20 is input as y '(y' is one of a plurality of data numbers for one cycle). -Indicating the amplitude or amplitude). Thereafter, in Q43, it is determined whether or not the flag is 0. This Q43
When the determination is YES, the ANC control is turned on from the OFF state, and the ANC control is newly started. At this time, it is determined in Q44 whether or not the input y 'is substantially zero. If the determination in Q44 is NO, after y ′ is set to 0 in Q45, Q ′
In step 47, after y ′ is set as y ″, y ″ is output from the adjustment unit 54 to the speaker 11.

If the determination in Q44 is YES, Q
After setting the flag to 1 in 46, the flow shifts to Q47. After passing through Q46, the process of correcting y 'to 0 is not performed, and the input y' is used as it is as the output y "of the adjustment unit 54. After passing through Q46, the determination of Q43 is NO. In this case, the input y 'from the ANC control unit 20 is always used as the output y "of the adjusting unit 54 (the role of the adjusting unit 54 ends).

Thus, as long as y ′ is not substantially zero, Q
By the process of 45, the amplitude of the vibration for reduction becomes 0,
In effect, the state is the same as that in which no vibration for reduction is generated. Then, at the time when y ′ becomes substantially zero, the vibration for reduction starts to be output from the speaker 11. Of course, the time when the determination of Q44 is YES corresponds to the output start time in FIG.

FIG. 16 shows another example of the control contents of the output data adjusting section 54, which corresponds to the control contents of gradually increasing the output gain as shown in FIG. This FIG.
First, in Q51, it is determined whether or not the determination result of the determination unit 51 is ON. If the determination in Q51 is NO, the output gain β is set to 0 in Q58.

If the determination in Q51 is YES, after y 'is input in Q52, in Q53, y' is multiplied by an output gain β (initially 0 from the setting in Q58). Then, the output y ″ is set.
At 54, after y ″ is output to the speaker 11, Q
55, the output gain β is increased by a predetermined increment dβ (1.
(A value sufficiently smaller than 0) is added to obtain a new output gain β. Thereafter, in Q56, β is 1.0
It is determined whether or not the above has been achieved. If the determination in Q56 is NO, the control is returned as it is, and Q52 to Q5
5 is repeated to gradually increase the output gain β. When the output gain β becomes 1.0, the determination of Q56 becomes YES, and in this case, in Q57,
β is set to 1.0. After passing through this Q57, the input y 'and the output y "always have the same value (the role of the data adjusting unit 54 ends).

Although the embodiment has been described above, the vibration source for reduction is not limited to the speaker, but may be a variable displacement type actuator interposed between the engine and the vehicle body.

[Brief description of the drawings]

FIG. 1 is a top view of a vehicle to which the present invention is applied.

FIG. 2 is an overall control system diagram for generating a vibration for reduction.

FIG. 3 is a block diagram showing a configuration of a portion for optimizing the vibration for reduction in FIG. 2;

FIG. 4 is a diagram showing a control system for setting an initial value.

FIG. 5 is a diagram schematically showing correction of data length.

FIG. 6 is a diagram schematically showing output of vibration for reduction from the timing of amplitude 0.

FIG. 7 is a diagram schematically illustrating a state in which the output gain of the vibration for reduction is gradually increased.

FIG. 8 is a flowchart showing the control contents of an ON / OFF determination section of ANC control.

FIG. 9 is a flowchart showing control contents of an initial data correction unit.

FIG. 10 is a flow chart showing control contents of data length correction.
G.

FIG. 11 is a flowchart showing control contents of data length correction.
G.

FIG. 12 is a diagram schematically showing contents of interpolation performed at the time of data length correction.

FIG. 13 is a diagram showing a circuit example when data length correction is performed using an analog circuit.

FIG. 14 is a main part flowchart showing control contents when initial value setting is prohibited.

FIG. 15 is a flowchart for performing the control contents shown in FIG. 6;

FIG. 16 is a flowchart for performing the control contents shown in FIG. 7;

[Explanation of symbols]

 1: automobile 2: cabin 8: engine (vibration source) 11: speaker (vibration generation source for reduction) 12: microphone (vibration detection means) 20: vibration generation circuit for reduction 51: ON / OFF of vibration reduction control Judgment unit 52: Memory 53: Initial data correction unit 54: Output data adjustment unit

Continuation of the front page (56) References JP-A-4-352197 (JP, A) JP-A-4-303898 (JP, A) JP-A-5-127684 (JP, A) JP-A-6-274184 (JP, A) JP-A-6-282284 (JP, A) JP-A-6-337686 (JP, A) JP-A-6-266376 (JP, A) JP-A-4-109124 (JP, A) JP-A-4-347559 (JP, A) JP-A-5-39710 (JP, A) JP-A-5-80777 (JP, A) JP-A-4-203406 (JP, A) JP-A-4-287733 (JP, A A) JP-A-1-191198 (JP, A) JP-A-1-257798 (JP, A) JP-A-4-505221 (JP, A) JP-A-5-503622 (JP, A) (58) Survey Field (Int.Cl. ⁷ , DB name) G10K 11/178 B60R 11/02 F16F 15/02 G10K 11/16 F01K 1/00 F01K 1/06

Claims (4)

(57) [Claims] 1. A periodic vibration generated by the first vibration source and a vibration control device for a vehicle to be reduced in the predetermined space of the vehicle, and cycle detecting means for detecting the first period of vibration, said first A second vibration source for outputting a second vibration for reducing the vibration energy of one vibration, a vibration detecting means for detecting a vibration in the predetermined space, information corresponding to a waveform signal for one cycle of the second vibration, sand
That is, an n-dimensional matrix having n waveform amplitude values as constituent elements
For output data that is a
The multiplied value by the sampling period at the time of the time series conversion becomes the same as the period of the first vibration detected by the period detecting means.
A setting unit configured to set as the set by the setting means in the previous control cycle
Output data, the based on the transfer characteristic between the output and the second vibration source and said vibration detecting means of said vibration detecting means
Correction means for correcting each cycle, and the configuration of the output data corrected by the correction means
By arranging the elements at every sampling cycle, the second vibration
Time-series converted to a waveform signal of
An output unit for outputting a waveform signal from the second vibration source; and a correction unit when the predetermined control start condition is satisfied.
And control means for starting operation of the serial output means, at the start of control in the control unit, during the last
At the end of the vibration reduction control.
An initial value setting means for setting output data of vibration as an initial value at the start of control. 2. The system according to claim 1 , wherein the first vibration source is an engine, and an engine speed at the time of ending the previous vibration reduction control and an engine speed at the time of disclosing the new vibration reduction control are set forth. A vibration control device for a vehicle , further comprising prohibiting means for prohibiting setting of an initial value by the initial value setting means when the difference is equal to or more than a predetermined value. 3. The output of the initial value set by the initial value setting means according to claim 1 ,
Amplitude further comprises an output timing setting means for causing the 0 or substantially 0. The timing, that
A vibration control device for a vehicle . 4. The method of claim 1, initially starting the control of the vibration reduction, the output gain is gradually increased, eventually are predetermined output gain, this
And a vibration control device for a vehicle .