JP2010202162A - Active vibration and noise control device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an active vibration and noise control device capable of performing a noise reduction control without giving a sense of incongruity when a gear shift occurs. <P>SOLUTION: This active vibration and noise control device includes acceleration sensors 10 for detecting the vibration occurring inside a cabin, an actuator 20 for applying a wave motion to the inside of the cabin, and a control instruction value calculation part 32 for generating control instruction signals u for driving the actuator 20 so that road noise can be reduced according to the signals detected by the acceleration sensors 10. The control instruction value calculation part 32 estimates the vibration intruding from a transmission to the installation positions of the accelerator sensors 10 according to the signals output from the acceleration sensors 10, and removes the estimated vibration from the signals output from the acceleration sensors 10 to generate the control instruction signals u. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to an active vibration noise control device that reduces noise generated inside a structure such as a vehicle by outputting a wave.

  For active noise control devices that actively reduce vehicle interior noise, the shift change signal is used to prevent the system from diverging due to vibration changes when engine pulses change suddenly, such as during a shift change or acceleration. A technique for stopping control when a detection or an acceleration signal is detected is known (see Patent Document 1).

JP 2006-36061 A

  However, when the noise control device described in Patent Document 1 described above is used, noise control is stopped at the time of shift change or acceleration, while control is performed at normal times. And the passengers feel uncomfortable.

  The present invention has been made to solve such a conventional problem, and an object of the present invention is to perform noise reduction control without a sense of incongruity even when a second vibration such as a shift change occurs. It is an object of the present invention to provide an active vibration noise control device capable of performing

  The present invention provides a sensor that is arranged in a structure and detects vibration generated in the structure, wave applying means for applying a wave in the structure, and a first vibration source based on a signal from the sensor. Control means for controlling the wave applying means so as to reduce noise entering the structure. The control means estimates a second vibration source vibration that enters the sensor installation position from a second vibration source different from the first vibration source based on the output signal of the sensor, and estimates the second Two vibration source vibrations are removed from the output signal of the sensor to generate a control command signal for the wave applying means.

  In the present invention, by removing the second vibration source vibration that intrudes into the output signal of the sensor, noise reduction caused by the first vibration source can be reduced even in a situation where vibration caused by the second vibration source is generated. Control can be continued.

It is explanatory drawing which shows the outline of the active vibration noise control apparatus which concerns on this invention, (a) shows the whole vehicle, (b) shows the tire periphery. It is a block diagram which shows the structure of the active vibration noise control apparatus which concerns on this invention. It is a block diagram which shows the detailed structure of the control command value calculation part of the active vibration noise control apparatus which concerns on 1st Embodiment of this invention. It is a flowchart which shows the process sequence by the control command value calculation part of the active vibration noise control apparatus which concerns on 1st Embodiment of this invention. It is a flowchart which shows the process sequence by the T / M vibration calculation part of the active vibration noise control apparatus which concerns on 1st Embodiment of this invention. It is a block diagram which shows the structure which calculates the filter coefficient used with a controller of the active vibration noise control apparatus which concerns on 1st Embodiment of this invention. It is a block diagram which shows the detailed structure of the control command value calculation part of the active vibration noise control apparatus which concerns on 2nd Embodiment of this invention. It is a flowchart which shows the process sequence by the control command value calculation part of the active vibration noise control apparatus which concerns on 2nd Embodiment of this invention. It is a flowchart which shows the process sequence by the T / M vibration calculation part of the active vibration noise control apparatus which concerns on 2nd Embodiment of this invention. It is a flowchart which shows the process sequence by the T / M vibration calculation part of the active vibration noise control apparatus which concerns on 3rd Embodiment of this invention.

[First Embodiment]
Hereinafter, embodiments of the present invention will be described with reference to the drawings. The typical causes of vehicle interior noise entering from the outside of the vehicle (structure) are engine noise caused by engine vibration, and noise caused by road surface unevenness entering from tires (No. 1) 1 vibration source; hereinafter referred to as “road noise”), wind noise generated by the air flow during traveling, and the like. In the present embodiment, reduction of road noise will be mainly described from the above-described noises.

  FIG. 1 is an explanatory diagram schematically showing main propagation paths of vehicle body vibration and road noise caused by road surface unevenness when the vehicle is traveling. FIG. FIG. 1B is a side view of the tire 200. FIG.

  As shown in FIG. 1 (a), vibrations that are the main components of road noise entering the vehicle body from the four tires 200 are first attached to the axle 120 and suspension 130 shown in FIG. 1 (b) (not shown). The member 140 enters a highly rigid beam-like member called a member 140. Thereafter, the vibration propagates to the floor panel 110, which is a plate member having a relatively low rigidity and surrounded by the member 140, and the floor panel 110 vibrates.

  Furthermore, the vibration of the floor panel 110 causes air vibrations in the passenger compartment and causes a resonance phenomenon in the passenger compartment, so that road noise can be heard in a predetermined space 100 in the passenger compartment. In this embodiment, in order to avoid complexity, only the space 100 (control space in the structure) near the right ear of the driver's seat is handled as the noise reduction control space.

  When a plurality of seats or a plurality of ear spaces are used as the control space, the setting may be changed as appropriate. Although noise is also generated by vibration of the roof panel and window glass (both not shown) in addition to the floor panel 110, most of the road noise that intrudes mainly from the mounting portion of the suspension 130 is generated by the floor panel 110. It is known to be caused by vibration. For this reason, if noise control is performed so as to cancel road noise caused by vibration of the floor panel 110, road noise can be reduced.

  In the present invention, a sensor (acceleration sensor 10 to be described later) is disposed on the floor panel 110, vehicle interior noise is estimated based on the output signal of this sensor, and a control command signal is generated by the control command value generating means. A technique is adopted in which control sound generated by an actuator (wave application unit) provided on the floor panel 110 is input into the vehicle interior based on the control command signal.

  Here, the present invention uses a method of estimating the noise of the control space 100 from the signal of the acceleration sensor 10 without using a microphone as a sensor. Since the acceleration sensor 10 installed on the floor panel 110 or the member 140 is used, road noise caused by the floor panel 110 is handled as a control target. Here, the reason why the floor panel 110 or the member 140 is selected as the installation location of the acceleration sensor 10 is that coherence with the vehicle interior noise (definition will be described later) is high.

  In addition, since all noises generated from the floor panel 110 and the member 140 are included as control targets, part of the engine noise and wind noise generated by the air flowing through the bottom of the vehicle body can be handled in the same manner.

  Further, the scope of the effect of the present invention is not limited to the category of noise reduction due to vibration of the floor panel 110, but is generated by the same mechanism such as a dash panel, a front glass, and a roof panel (both not shown). The same effect can be obtained for the noise generation source if the present invention is applied to the part concerned.

  FIG. 2 is an explanatory diagram schematically showing the configuration of the active vibration noise control device according to the first embodiment of the present invention. As shown in FIG. 2, the active vibration noise control apparatus according to the present embodiment includes four acceleration sensors 10a, 10b, 10c, 10d (hereinafter referred to as individual) for measuring vibrations of the floor panel 110 and the member 140. If there is no need to distinguish between the two actuators 20a and 20b (hereinafter referred to as "acceleration sensor 10") as two wave applying means for applying vibration to the floor panel 110 or the member 140 If there is no control signal, it is referred to as “actuator 20”). A control command body 30 for controlling the actuator 20 is calculated by calculating a control command signal for reducing vehicle interior noise based on the acceleration signal detected by the acceleration sensor 10. I have.

  Here, in this embodiment, a piezo-electric actuator is used as an example of the actuator 20. In addition, the actuator 20 can be installed in a part such as a dash panel, a front glass, a door panel, or a roof panel without adopting a form of installation on the floor panel 110 or the member 140. Furthermore, a speaker installed in the passenger compartment can be used as the actuator 20.

  An input signal of the control device main body 30 is an output of each acceleration sensor 10 (acceleration signals α1 to α4), and an output signal is a control command signal u (u1, u2) output to the actuator 20.

  A sufficient number of actuators 20 are attached to appropriate positions on the floor panel 110 of the vehicle body in order to reduce noise in the control space 100.

Generally, the number of acceleration sensors 10 needs to be larger than the number of vibration sources. The specific number of acceleration sensors 10 and their installation positions are such that the coherence Cxy (ω) between each acceleration sensor 10 and the sound pressure of noise in the control space 100 expressed by the following equation (1) is sufficiently high. (For example, 0.9 or more).

  In the present embodiment, the number of acceleration sensors is four (10a, 10b, 10c, 10d), and the number of actuators is two (20a, 20b). In addition, the number of the acceleration sensors 10 and the actuators 20 is not limited to the above, and can be appropriately set to an arbitrary number.

  In the above equation (1), Pxy (ω) represents a cross power spectrum between acceleration and sound pressure, and Pxx (ω) and Pyy (ω) represent auto power spectra of acceleration and sound pressure, respectively. PH represents a Hermitian transpose matrix of P.

  The control device main body 30 includes an amplification unit 31 (31a to 31f) for signal amplification, and a control command value calculation unit (control unit) 32 that calculates and outputs a control command signal for reducing vehicle interior noise.

  When the acceleration sensor 10 is a so-called charge type, the amplifying units 31a to 31f perform conversion between charge and voltage.

  In addition, the engine 150 and the transmission 160 are mounted on the vehicle. In the present invention, the vibration (second vibration source) generated in the transmission 160 is removed from the vibrations that enter the acceleration sensor 10.

  FIG. 3 is a block diagram showing a detailed configuration of the control command value calculation unit 32 shown in FIG. As shown in FIG. 3, the control command value calculation unit 32 includes an A / D conversion unit 33, a T / M vibration calculation unit 34, a vibration propagation characteristic model 70, a controller 38, subtracters 35a and 35b, and A D / A converter 39 is provided.

  The A / D converter 33 converts the acceleration signals α1, α2, α3, and α4 detected by the acceleration sensor 10 (10a to 10d) and amplified by the amplifiers 31a to 31d into digital signals, and outputs them to the subtractor 35a. To do.

  The vibration propagation characteristic model 70 is a model of a transfer function when vibration generated in the actuator 20 goes around to the installation position of the acceleration sensor 10. Usually kept in memory in the form of an IIR filter for online processing. When a plurality of sensors and actuators are provided (in this embodiment, four acceleration sensors and two actuators), a filter corresponding to the number is held. In the vibration propagation characteristic model 70, the vibration generated by the actuator 20 at the installation position of the acceleration sensor 10 is calculated by multiplying the control command signal u by a model from the actuator 20 to the noise generated in the control space 100. When a speaker is used instead of the actuator 20, the vibration propagation characteristic model 70 uses a transfer function that causes speaker vibration to circulate to the installation position of the acceleration sensor 10. In this case, when the amount of transmission is small, the vibration propagation characteristic model 70 can be omitted.

  The subtractor 35a subtracts a vibration component (an output signal of the vibration propagation characteristic model 70) generated by the actuator 20 at the installation position of the acceleration sensor 10 from the acceleration signals α1 to α4 detected by the acceleration sensor 10. The signal obtained as a result is only the signal αd (hereinafter referred to as “subtraction signal αd”), which is a component that has entered from outside the vehicle, among vibrations detected by the acceleration sensor 10.

  The T / M (transmission) vibration calculation unit 34, based on the subtraction signal αd output from the subtractor 35a, a vibration component that enters the installation position of the acceleration sensor 10 from the transmission 160 shown in FIG. M vibration source vibration αT) is estimated.

  The subtractor 35 b subtracts the vibration component estimated by the T / M vibration calculator 34 from the subtraction signal αd, and outputs the subtracted signal to the controller 38.

  Based on the signal output from the subtractor 35b, the controller 38 calculates a control command signal u to be output to the actuator 20 so as to reduce noise generated in the control space 100 by a method described later.

  The D / A conversion unit 39 converts the control command signal u calculated by the controller 38 into an analog signal, and outputs the control command signal u converted into the analog signal to the amplification units 31e and 31f shown in FIG. In the present embodiment, the control command value calculation unit 32 (control unit) is mounted on a so-called CPU.

  Next, the processing procedure by the control command value calculation unit 32 will be described with reference to the flowchart shown in FIG.

  In step S11, acceleration signals α1 to α4 converted into digital signals by the A / D converter 33 are input to the subtractor 35a. Thereafter, the flow proceeds to step S12.

  In step S12, the output signal of the controller 38 one sample before is multiplied by a filter indicating the vibration propagation characteristic model 70. The calculated signal is output to the subtractor 35a. Thereafter, the flow proceeds to step S13.

  In step S13, the subtracter 35a subtracts the signal acquired in the process of step S12 from the acceleration signals α1 to α4 acquired in the process of step S11. The signal obtained as a result is set as a subtraction signal αd. Thereafter, the flow proceeds to step S14.

  In step S <b> 14, the T / M vibration calculation unit 34 executes a process of calculating a vibration component that enters from the transmission 160 to the installation position of the acceleration sensor 10. Details of this processing will be described later using the flowchart shown in FIG. Thereafter, the flow proceeds to step S15.

  In step S15, the subtractor 35b subtracts the signal (T / M vibration source vibration αT or “0”) obtained in the process of step S14 from the subtraction signal αd obtained in the process of step S13. Thereafter, the flow proceeds to step S16.

  In step S16, the controller 38 calculates a control command signal u for reducing noise in the control space 100 based on the signal acquired in the process of step S15. Thereafter, the flow proceeds to step S17.

  In step S <b> 17, the digital control command signal u calculated in the process of step S <b> 16 is converted into an analog signal by the D / A conversion unit 39 and used as an output of the control command value calculation unit 32. Thereafter, the flow ends.

  Next, a detailed procedure of the vibration calculation process by the T / M vibration calculation unit 34 shown in step S14 of FIG. 4 will be described with reference to the flowchart shown in FIG.

  First, in step S21, the shift command signal αtm is estimated using the subtraction signal αd. This calculation is performed as follows. First, the vehicle is subjected to a shift change, and the vibration generated at this time is measured by the acceleration sensor 10. Based on the input signal and the output signal at this time, the transfer function model GT from the shift command signal αtm to the installation position of the acceleration sensor 10 is identified. For example, the method described in “Adachi,“ System Identification for Control ”, Tokyo Denki University Press, 1996” may be used for the calculation of the transfer function model. Alternatively, the frequency characteristic may be measured and the transfer function model may be obtained by mode analysis.

  Next, at the time of traveling, an acceleration sensor is arranged at a point near the tire where the coherence between the output signal of the acceleration sensor 10 on the floor panel 110 (see the above-described equation (1)) is high, and the acceleration signal and on the floor A transfer function Gr between the output signal of the acceleration sensor 10 is obtained. The modeling method may be the above method.

Therefore, transmission of signals from the acceleration αtire near the tire and the shift command signal αtm to the subtraction signal αd of the acceleration sensor 10 on the floor panel 110 is expressed by the following equation (2).

Next, the matrix [Gr GT] shown in the equation (2) is subjected to singular value decomposition to obtain the following equation (3).

  Here, U and V indicate orthogonal matrices (or unitary matrices) that appear in the calculation of singular value decomposition. Σ is a matrix arranged in diagonal components in descending order of singular values.

Of the components of this matrix Σ, the singular value component having a relatively small value is set to 0, and by obtaining a pseudo inverse matrix Σs + shown in the following equation (4), the acceleration αtire near the tire and the shift command signal αtm are obtained. Can be estimated.

  A small singular value component may be selected by providing a predetermined ratio with respect to a certain threshold or the maximum singular value and selecting a singular value lower than that. By extracting the transfer function matrix in the last column of the equation (4), a transfer function for estimating the shift command signal αtm is obtained. By the above method, it is possible to estimate the vibration (shift command signal αtm) due to the shift change.

  That is, the T / M vibration calculation unit 34 estimates the shift command signal αtm using the transfer characteristic from the second vibration source (transmission) to the sensor installation position, and further multiplies the shift command signal αtm by the transfer function. Thus, the T / M vibration source vibration αT (second vibration source vibration) is obtained. Since the T / M vibration source vibration αT is specified using the transfer function, it can be estimated only by addition and multiplication, and the calculation time can be shortened. Further, an appropriate amount of T / M vibration source vibration αT can be obtained, and more accurate control can be performed.

  Further, the T / M vibration calculation unit 34 calculates the second vibration source vibration from the vibration (αtire) at a position highly related to the vibration of the second vibration source near the installation position of the second vibration source. Is estimated. Therefore, in addition to the output signal of the acceleration sensor 10, the second vibration is removed using the vibration in the vicinity of the second vibration source, so that the estimation accuracy of the second vibration can be improved. Further, vibration information in the middle of being transmitted from the vibration source to the installation position of the acceleration sensor 10 can be measured.

  Further, the T / M vibration source vibration αT may be removed when vibration having a high degree of relevance with vibration generated in the transmission reaches a predetermined threshold value. Therefore, by using the vibration in the vicinity of the second vibration source, it is possible to determine the start of the second vibration removal with higher accuracy.

  In step S22, it is determined whether or not the shift command signal αtm estimated in the process of step S21 is larger than a preset threshold value. If the shift command signal αtm is greater than or equal to this threshold value, it is determined that a shift change has occurred, and the flow moves to step S23.

  On the other hand, if the shift command signal αtm is less than the threshold value, it is determined that no shift change has occurred, and the flow proceeds to step S24.

  In step S23, the transmission command signal αtm is multiplied by the transfer function obtained by the above equation (4) to obtain the T / M vibration source vibration αT, which is output to the subtractor 35b.

  In step S24, it is determined that no shift change has occurred, αtm = 0 is set, and the calculation is terminated. In this process, by setting αtm = 0, it is possible to prevent output of noise superimposed on the T / M vibration source vibration αT calculated by the equation (4).

  In the process of step S21, the shift command signal αtm is estimated by the above-described equations (2) to (4). However, when the transfer function Gr is very small, it is estimated using only the transfer function model GT. It is also possible to do.

  Further, when the estimated T / M vibration source vibration αT (second vibration source vibration) exceeds a predetermined threshold by the process of step S22, the T / M vibration source vibration αT is removed from the subtraction signal αd. To control. Therefore, it is possible to specify the timing for starting the removal of the vibration by the second vibration source, and it is not necessary to always remove the vibration by the second vibration source.

  FIG. 6 is a block diagram for designing a filter for calculating the control command signal u by the controller 38. A block 51 (denoted as C in FIG. 6) shown in FIG. 6 represents a control command value generation filter to be designed, and a block 50 represents the control space 100 based on the acceleration signals α1 to α4 detected by each acceleration sensor 10 during traveling. The transfer function Gα up to the sound pressure (SPL *; Sound Pressure Level) is shown.

  A block 60 indicates a transfer function Gp from the control command signal u (u1, u2) output to the actuator 20 to the sound pressure in the control space 100. In FIG. 6, the signal line is described as a single line, but when there are a plurality of accelerations, control spaces, and actuators, a plurality of signal lines corresponding to the number of the signal lines are shown. In that case, each block is a multi-input, multi-output block.

  When a speaker is used as the actuator 20 instead of the piezoelectric actuator, the block 60 uses a transfer function from a command signal output to the speaker to the sound pressure in the control space 100. Blocks 40a and 40b (denoted as Wc2 and Wc3 in FIG. 6) and 40c (denoted as Wc1 in FIG. 6) are design parameters indicating weight functions. Blocks 40a and 40b are used to limit the maximum voltage of the control command signals u1 and u2.

  Increasing the values of the weight functions Wc2, Wc3 of the blocks 40a, 40b decreases the corresponding actuator gain. It is also possible to give these weight functions Wc2 and Wc3 frequency characteristics. In this case, the gain can be reduced only in a certain frequency band. Further, the weight function Wc1 of the block 40c has a frequency characteristic that is an outline of the filter C shown in the block 51. In other words, when it is desired to lower the filter gain outside the control frequency band, a band pass filter may be used. As a result, the filter gain outside the control band is lowered, and the voltage consumption can be reduced.

  The transfer function of each block uses a mathematical model expressed by a differential equation or Laplace transform. This modeling may be performed as follows.

  The transfer function Gp shown in the block 60 is a system identification using a sound pressure signal and an input signal in a control space determined according to the occupant position obtained by inputting white noise or an impulse signal to the actuator 20. Can be obtained. The system identification method is described in, for example, “Structural Dynamical Toolbox” which is a toolbox of the control system design tool MATLAB and the above-mentioned literature “Adachi,“ System Identification for Control ”, Tokyo Denki University Press, 1996”. The subspace identification method may be used. Further, the transfer function Gα of the block 50 can be obtained by measuring the acceleration signal and sound pressure level during traveling and using the above method.

  At this time, the filter C is designed to minimize the transfer function from the acceleration signals α1 to α4 to the sound pressure (SPL *) and the norm of the transfer function from the acceleration signals α1 to α4 to the control command signals u1 and u2. . Various design methods can be considered. For example, design using the H∞ control method or H2 control method described in “Hosoe, Araki,“ Control System Design—H∞ Control and its Applications ”, Asakura Shoten, 1994”. can do.

  In the present embodiment, the design is performed using two weight functions (design parameters) Wc2 and Wc3 shown in the blocks 40a and 40b, but the design is performed using other weight functions (design parameters) described in the above-mentioned reference. Also good. When the transfer functions Gα and Gp are modeled as a continuous time system, the obtained filter is discretized using Tustin transform or the like. Alternatively, the transfer functions Gα and Gp may be modeled as a discrete time system, and the digital controller may be designed using a design method for the discrete time system.

  As described above, the active vibration noise control apparatus according to the first embodiment is provided with the above-described system configuration, thereby causing vibrations entering from the road surface without stopping the control of noise reduction when shifting the transmission. Thus, the control for reducing the noise generated in the control space 100 can be continuously executed.

  In the present embodiment, the transmission signal is applied as a signal to be subtracted from the acceleration signals α1 to α4. However, other vibrations such as engine vibration, fan vibration, air conditioner compressor vibration, and speaker vibration can be specified. If so, the same method can be applied.

[Second Embodiment]
Next, a second embodiment of the present invention will be described. Since the active vibration noise control apparatus according to the second embodiment is different from the first embodiment described above only in the configuration of the control command value calculation unit 32 shown in FIG. The configuration of the control command value calculation unit 32 according to the second embodiment will be described with reference to the block diagram shown.

  The control command value calculation unit 32 according to the second embodiment is different from that shown in FIG. 3 in that a shift command signal αtm supplied from the outside is input to the T / M vibration calculation unit 34. Other configurations are the same as those in FIG. The shift command signal αtm can be acquired, for example, via a CAN or a dedicated line installed in the vehicle.

  Next, a processing procedure by the control command value calculation unit 32 according to the second embodiment will be described with reference to a flowchart shown in FIG.

  In step S31, the acceleration signals α1 to α4 input to the A / D conversion unit 33 are converted into digital signals and then output to the subtractor 35a. Thereafter, the flow proceeds to step S32.

  In step S32, a shift command signal αtm output from the transmission 160 is acquired from CAN, for example. In addition, you may acquire via other dedicated lines instead of CAN. Thereafter, the flow proceeds to step S33.

  In step S33, the filter indicating the vibration propagation characteristic model 70 is multiplied by the output signal of the controller 38 one sample before. The calculated signal is output to the subtractor 35a. Thereafter, the flow moves to step S34.

  In step S34, the subtracter 35a subtracts the signal acquired in the process of step S33 from the acceleration signals α1 to α4 acquired in the process of step S31. A signal obtained as a subtraction result is defined as a subtraction signal αd. Thereafter, the flow proceeds to step S35.

  In step S35, the vibration that intrudes into the acceleration sensor 10 from the transmission 160 based on the shift command signal αtm acquired in the process of step S32 and the subtraction signal αd acquired in the process of step S34 in the T / M vibration calculation unit 34. The process of calculating is executed. Details of this processing will be described later based on the flowchart shown in FIG. Thereafter, the flow proceeds to step S36.

  In step S36, in the subtractor 35b, the signal obtained in the process in step S14 (vibration Cx ^ (t) calculated in the process in step S42 described later, or " 0 ") is subtracted. Thereafter, the flow proceeds to step S37.

  In step S37, the controller 38 calculates a control command signal u for reducing noise in the control space 100 based on the signal acquired in the process of step S36. The filter used in the controller 38 is designed using the same method as in the first embodiment described above. Thereafter, the flow proceeds to step S38.

  In step S <b> 38, the digital control command signal u calculated in step S <b> 37 is converted into an analog signal by the D / A conversion unit 39 and used as an output of the control command value calculation unit 32. Thereafter, the flow ends.

  Next, a detailed procedure of vibration calculation processing by the T / M vibration calculation unit 34 shown in step S35 of FIG. 8 will be described with reference to a flowchart shown in FIG.

  In step S41, it is determined whether or not a shift command signal αtm supplied from the outside indicates a shift. If it is determined that a shift is instructed, the process proceeds to step S42. If it is determined that no shift is instructed, the process proceeds to step S43.

In step S42, the vibration Cx ^ (t) generated by the vibration of the transmission vibration source at the installation position of the acceleration sensor is estimated using the subtraction signal αd and the shift command signal αtm. This technique is performed as follows. First, assuming that noise does not enter the input αtire of the above-described equation (2), the equation (2) is expressed in the state space, and the following equation (5) is obtained.

  Here, x is a state variable, and matrices (A, B, C) are state space representations of the transfer function GT in the above equation (2). Although the D matrix is not shown for simplicity, a direct term may exist. w represents noise that enters between the transmission shift signal and the acceleration sensor 10, and this covariance is measured and given in advance. It is specified as the representative value.

  Further, v is a vibration component that enters the acceleration from the tire, and the covariance thereof is measured in advance as the covariance of Gr and αtire. That is, the first term of the second formula of the above-described formula (5) represents the acceleration transmitted from the transmission vibration source, and the second term represents the acceleration that has entered from the tire. The sum of these represents that the acceleration signal is established.

  By constructing a Kalman filter for the system expressed by the above equation (5), the estimated value x (^) of the state x is calculated from αd and αtm, and as a result, the vibration generated by the shift is generated at the acceleration sensor position. The vibration Cx ^ (t) to be created is estimated. In step S42, the estimated vibration Cx ^ (t) is output, and the flow ends.

  In step S43, 0 is output and the calculation is terminated.

  Further, the T / M vibration calculation unit 34 uses the transfer characteristics from the first vibration source to the installation position of the acceleration sensor 10 and the transfer characteristics from the second vibration source to the installation position of the acceleration sensor 10 to calculate T / M The M vibration source vibration αT (second vibration source vibration) is estimated. Therefore, since the transfer characteristic from the first vibration source to the acceleration sensor 10 is used in addition to the transfer characteristic from the second vibration source to the acceleration sensor 10, the estimation accuracy can be improved.

  Further, by using the above-described method, it is possible to specify the timing at which transmission vibration subtraction is started by the processing of step S41 shown in FIG. 9, and to reduce the calculation load in the normal state. Further, by the process in step S42 shown in FIG. 9, the vibration generated at the installation position of the acceleration sensor 10 due to the transmission vibration can be estimated more accurately.

  Further, in the second embodiment, the shift command signal αtm acquired by CAN or the like is used in addition to the acceleration signal α. However, a signal indicating an operation state, such as a signal for monitoring the hydraulic state, or a signal attached to the transmission housing. Further, an acceleration sensor signal or an acceleration sensor signal attached to the transmission mount may be used.

  By using the system configuration described above, it is possible to continue to reduce noise generated due to vibration invading from the road surface without stopping noise reduction control even at the time of shifting by the transmission. In the second embodiment, the transmission signal is used as a signal to be subtracted from the acceleration signals α1 to α4. However, other sources such as engine vibration, fan vibration, air conditioner compressor vibration, and speaker vibration can be specified. Any vibration can be applied.

  In that case, instead of the shift command signal αtm shown in FIG. 7, the signals of the respective vibration sources may be input and used as the calculation start timing.

[Third Embodiment]
Next, an active vibration noise control device according to a third embodiment of the present invention will be described. Since the apparatus configuration is the same as that of the second embodiment, description of the configuration is omitted.

  In the third embodiment, it is assumed that the signal to be subtracted from the acceleration signals α1 to α4 is vibration generated due to engine vibration (second vibration source). In this case, the shift command signal αtm shown in FIG. 7 is replaced with an engine pulse signal or a crank angle sensor signal.

  Hereinafter, the procedure of the vibration calculation process by the T / M vibration calculation unit 34 according to the third embodiment will be described with reference to the flowchart shown in FIG.

  First, in step S51, the engine speed is acquired based on a sensor signal (not shown). Thereafter, the flow proceeds to step S52.

  In step S52, the engine vibration source vibration αT (second vibration source vibration) is estimated using the subtraction signal αd. This estimation can be executed by using the engine vibration source vibration αT in place of the shift command signal αtm in the above-described equations (2) to (4). Thereafter, the flow proceeds to step S53.

  In step S53, the frequency of the engine vibration source vibration αT is estimated based on the engine speed acquired in the process of step S51. At this time, the calculation is performed including the main component obtained from the main rotation cycle of the engine and the harmonic component of the frequency. The ratio of the main component and the harmonic component for each rotation number is stored in advance in the memory. Thereafter, the flow moves to step S54.

  In step S54, it is determined whether or not the cross-correlation function between the sine wave having the engine vibration frequency acquired in step S53 and the engine vibration source vibration αT acquired in step S52 is greater than or equal to a predetermined threshold value. If it is determined that the value is equal to or greater than the threshold value, the flow proceeds to step S55, and if it is less than the threshold value, the flow returns to step S52.

  In step S55, the engine vibration source vibration αT is multiplied by a transfer function from the engine vibration source vibration αT to the acceleration at the installation position of the acceleration sensor 10. This transfer function design method is the same as the method described in the first embodiment. Thereafter, the calculation is terminated.

  Here, in the process of step S52, the method of estimating the engine vibration source vibration αT using the above-described equations (2) to (4) based on the subtraction signal αd has been described. However, the tacho pulse, the crank angle, etc. The operation amount and the operating state can be measured, and the second vibration can also be estimated using the equation (2) based on those signals.

  That is, the control command value calculation unit 32 estimates the second vibration source vibration αT based on the output signal of the acceleration sensor 10 and the operation amount for operating the second vibration source. Since the second vibration source vibration αT is estimated using the operation amount of the second vibration source in addition to the output signal of the acceleration sensor 10, the estimation accuracy of the second vibration can be improved.

  Further, the control command value calculation unit 32 estimates the second vibration source vibration αT based on the output signal of the acceleration sensor 10 and the operating state of the second vibration source. And since it removes using the driving | running state of a 2nd vibration source in addition to the output signal of the acceleration sensor 10, the estimation precision of a 2nd vibration can be improved. Further, the vibration source signal at a position closer to the vibration generating source can be measured.

  Furthermore, it is possible to control to remove the second vibration source vibration αT from the subtraction signal αd based on the operation amount such as the transmission, the engine, the tacho pulse and the crank angle, and the operation state. Therefore, it is possible to determine the start of removal with higher accuracy by using the operation amount of the second vibration source, and to start removal with higher accuracy by using the operation state of the second vibration source. Judgment can be made.

  Further, in step S53 described above, the calculation is performed including the principal component obtained from the main rotation cycle of the engine that is the vibration source performing the periodic motion and the harmonic component of the frequency, and the correlation is performed in the process of step S54. It is also possible to perform a subtraction process in the subtractor 35b when it is determined that is high. Therefore, when performing periodic motion, it can be estimated that the frequency and overtone are the second vibration, so that the vibration caused by the second vibration source can be more accurately removed.

  Further, an acceleration sensor may be arranged at a point where the coherence with the acceleration sensor 10 is sufficiently high and in the vicinity of the engine mount, and the engine vibration source vibration αT may be estimated based on a detection signal of the acceleration sensor.

  In the third embodiment, it is possible to evaluate whether or not the engine vibration source vibration αT calculated from the acceleration sensor 10 can be correctly estimated by directly measuring the engine frequency and using the value. If a vibration having a frequency different from that of the engine vibration is estimated, the estimated value is inaccurate, and it is considered that some error is inserted in the acceleration signal. Therefore, the estimation is performed again. By this method, it is possible to remove only the vibration of the main frequency of the engine vibration and its harmonic component.

  In the third embodiment, in addition to the engine vibration, the generated signal can be measured among periodic vibrations generated in the vehicle body, such as vibrations caused by the rotation of the fan and vibrations caused by the rotation of the air conditioner compressor. If so, it can be applied.

  Each embodiment described above is an example of application of the present invention, and the technical scope of the present invention is not intended to be limited to the contents described in the above-described embodiment. . That is, the technical scope of the present invention is not limited to the specific technical items disclosed in the above-described embodiments, but includes various modifications, changes, alternative technologies, and the like that can be easily derived from the disclosure.

  The embodiment of the present specification is an embodiment of the present invention for a vehicle. For example, when noise is reduced inside a certain structure, when vibration other than vibration for which noise reduction is desired enters from outside. Also, the effect of the present invention can be obtained.

  The present invention is extremely useful for reducing noise generated in a vehicle when a transmission shift change occurs.

10 (10a to 10d) Acceleration sensor 20 (20a, 20b) Actuator 30 Control device body 31 (31a to 31f) Amplifying unit 32 Control command value calculation unit 33 A / D conversion unit 34 T / M vibration calculation unit 35a Subtractor 35b Subtractor 38 Controller 39 D / A converter 40a, 40b, 40c Weight function 50 Transfer function (Gα)
51 Filter (C)
60 Transfer function (Gp)
70 Vibration propagation characteristic model 100 Control space (predetermined space)
110 Floor panel 120 Axle 130 Suspension 140 Member 150 Engine 160 Transmission 200 Tire

Claims (12)

A sensor disposed in the structure and detecting vibrations generated in the structure;
Wave applying means for applying a wave in the structure;
Control means for controlling the wave applying means so as to reduce noise intruding into the structure from the first vibration source based on the signal of the sensor;
The control means estimates a second vibration source vibration that enters the sensor installation position from a second vibration source different from the first vibration source based on an output signal of the sensor, and estimates the second vibration An active vibration and noise control apparatus characterized by generating a control command signal for wave applying means by removing source vibration from an output signal of the sensor.   2. The active vibration noise control apparatus according to claim 1, wherein the control unit estimates vibration of the second vibration source using a transfer characteristic from the second vibration source to the sensor installation position.   3. The control device according to claim 1, wherein the control unit estimates the second vibration source vibration based on an output signal of the sensor and an operation amount for operating the second vibration source. An active vibration noise control device according to claim 1.   The control unit estimates the second vibration source vibration based on an output signal of the sensor and an operating state of the second vibration source. The active vibration noise control apparatus as described.   The control means estimates the second vibration source vibration from vibration at a position highly related to the vibration by the second vibration source at or near the installation position of the second vibration source. The active vibration noise control device according to claim 1, wherein the active vibration noise control device is provided.   The control means uses the transmission characteristic from the first vibration source to the sensor installation position and the transmission characteristic from the second vibration source to the sensor installation position to perform the second vibration source vibration. The active vibration noise control device according to claim 1, wherein the active vibration noise control device is estimated.   The control means removes the estimated second vibration source vibration from the output signal of the sensor when the estimated second vibration source vibration exceeds a predetermined threshold. The active vibration noise control device according to claim 6.   The control means determines whether or not to remove the estimated second vibration source vibration from the output signal of the sensor, based on an operation amount for operating the second vibration source. The active vibration noise control device according to any one of claims 1 to 6.   The control means determines whether or not to remove the estimated second vibration source vibration from the output signal of the sensor based on an operating state of the second vibration source. The active vibration noise control device according to claim 6.   Whether the control means removes the estimated second vibration source vibration from the output signal of the sensor based on a vibration highly related to the vibration generated in the second vibration source and a predetermined threshold value. The active vibration noise control device according to claim 1, wherein the active vibration noise control device is determined.   The control means, when the second vibration source generates a periodic vibration, removes only the signal of the periodic vibration frequency and the harmonic frequency. Item 11. The active vibration noise control device according to any one of Items 10 to 10.   The active vibration noise control device according to any one of claims 1 to 11, wherein the second vibration source is a transmission mounted on a vehicle.

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