A transfer function estimation apparatus and method for road noise active control system

Abstract

The present application relates to a kind of transfer function estimation equipment and method for road noise active control system, including exciter, acceleration sensor, sound sensor, volume sound source and data acquisition system;The force sensor of the exciter is fixedly connected with wheel axle head, when estimating transfer function, first obtain sound-vibration frequency response function matrix, sound-sound frequency response function matrix;The sound-sound frequency response function matrix obtained is superimposed, and the transfer function between anti-phase sound wave and residual signal is obtained;The sound-vibration frequency response function matrix obtained is superimposed, and the transfer function between reference signal and residual signal is obtained;According to different road noise active control system architecture, the required transfer function is called, with the advantages of improving the adaptability and noise reduction effect of road noise active control system.

Description

Technical Field

[0001] This invention belongs to the field of transfer function technology, and particularly relates to a transfer function estimation device and method for an active road noise control system. Background Technology

[0002] Road noise active control system (RNC) is an active noise reduction technology based on the principle of anti-phase acoustic wave cancellation. The main algorithm currently used is the FXLMS algorithm. There are three main road architectures: feedforward architecture, feedback architecture, and hybrid feedback architecture. In order to solve the time delay problem of anti-phase signal when using any architecture, it is necessary to estimate the transfer function of the system to ensure that the emitted anti-phase acoustic wave can achieve the condition of equal amplitude and anti-phase with the noise signal, thereby achieving the purpose of eliminating or suppressing road noise.

[0003] like Figure 1 As shown, there are two types of transfer functions that need to be estimated: 1. the transfer function P(z) between the reference signal sensor and the residual microphone; 2. the transfer function S(z) between the loudspeaker and the residual microphone. For front-feedback and hybrid-feedback architectures, both P(z) and S(z) need to be estimated simultaneously, while for back-feedback architectures, only S(z) needs to be estimated. Currently, the main method for transfer function estimation is to construct an FIR filter to simulate the transfer function, then train the filter offline using white noise, and use the resulting filter as the transfer function.

[0004] However, the above method has some problems:

[0005] 1. The transfer function estimated by this method is of low quality. It is only a simulation method and differs greatly from the actual transfer function of the system, resulting in an unsatisfactory noise reduction effect for the entire system.

[0006] 2. This method is a universal estimation, which has poor adaptability to different vehicle models or systems, resulting in unstable noise reduction effect of the entire system, especially when there are large differences in transmission characteristics between different vehicle models. Summary of the Invention

[0007] The objective of this invention is to provide a transfer function estimation device for an active road noise control system that has the advantages of improving the adaptability and noise reduction effect of the active road noise control system.

[0008] The first objective of this invention is achieved through the following technical solution:

[0009] A transfer function estimation device for an active road noise control system includes a vibrator, an acceleration sensor, a sound sensor, a volumetric sound source, and a data acquisition system. The data acquisition system is used to acquire signals emitted by the sound sensor, the vibrator, the acceleration sensor, the volumetric sound source, and a loudspeaker. The force sensor of the vibrator is fixedly connected to the wheel axle head, and the acceleration sensor is located on one side of the force sensor to obtain the relative phase information of the force sensor. The sound sensor is located inside the vehicle, the volumetric sound source is connected to the loudspeaker, and the data acquisition system is connected to the volumetric sound source, the vibrator, and the sound sensor.

[0010] As a further feature of the invention, the number and location of the sound sensors correspond to the requirements of the road noise active control system.

[0011] As a further feature of the invention, the sound sensor is provided with four.

[0012] As a further feature of the invention, the acceleration sensor is glued to one side of the force sensor, and the force sensor is glued to the wheel axle head.

[0013] The second objective of this invention is to propose a transfer function estimation method for an active road noise control system that has the advantages of improving the adaptability and noise reduction effect of the active road noise control system.

[0014] The second objective of this invention is achieved through the following technical solution:

[0015] A transfer function estimation method for an active road noise control system includes the following steps:

[0016] S1: Obtain the acoustic-vibration frequency response function matrix;

[0017] S2: Obtain the acoustic frequency response function matrix;

[0018] S3: Superimpose the obtained sound-to-sound frequency response function matrices to obtain the transfer function between the antiphase sound wave and the residual signal;

[0019] S4: Superimpose the obtained acoustic-vibration frequency response function matrices to obtain the transfer function between the reference signal and the residual signal;

[0020] S5: Call the required transfer function according to different road noise active control system architectures.

[0021] As a further provision of the invention, the step of obtaining the acoustic-vibration frequency response function matrix includes:

[0022] S11: Input a burst of random white noise signal into the exciter;

[0023] S12: The data acquisition system synchronously acquires signals from the sound sensor, exciter, and accelerometer, and processes the signals to obtain the acoustic-vibration frequency response function between the excitation point of the exciter and each sound sensor.

[0024] S13: Repeat S11 and S12 to measure the acoustic-vibration frequency response function between the exciter and each sound sensor in turn, so as to obtain the acoustic-vibration frequency response function matrix.

[0025] As a further provision of the invention, the step of obtaining the acoustic-vibration frequency response function matrix includes:

[0026] S21: Place the volumetric sound source at the mounting point of one of the speakers and install sound sensors inside the vehicle;

[0027] S22: Input a burst of random white noise signal into the volumetric sound source;

[0028] S23: The data acquisition system synchronously acquires signals emitted by the sound sensor and the volumetric sound source, processes them, and obtains the sound-sound frequency response function between the excitation point of the volumetric sound source and each sound sensor.

[0029] S24: Repeat steps S11, S12 and S13 to measure the acoustic frequency response function of each loudspeaker mounting point in turn, so as to obtain the acoustic frequency response function matrix.

[0030] As a further feature of the invention: in step S3, the obtained acoustic-acoustic frequency response function matrices are superimposed, and the superimposed result is assigned to S(z) to obtain the transfer function between the antiphase acoustic wave and the residual signal.

[0031] As a further feature of the invention: in step S4, the obtained acoustic-vibration frequency response function matrices are superimposed, and the superimposed result is assigned to P(z) to obtain the transfer function between the reference signal and the residual signal.

[0032] Compared with the prior art, the present invention has the following beneficial technical effects:

[0033] 1. This technical solution applies an experimental transfer function estimation method to a road noise active control system. It uses the sound-vibration frequency response function matrix to estimate the transfer function between the reference signal and the residual signal, and uses the sound-sound frequency response function matrix to estimate the transfer function between the antiphase sound wave and the residual signal, thereby improving the quality of transfer function estimation. Different transfer functions are used for different vehicle models, thereby improving the adaptability and noise reduction effect of the road noise active control system. Attached Figure Description

[0034] Figure 1 This is a diagram of the architecture of an active noise control system in the existing technology.

[0035] Figure 2 This is a schematic diagram showing the location of the vibrator, sound sensor, and volumetric sound source of the present invention, as well as the principle for obtaining the transfer function.

[0036] Figure 3 This is a schematic diagram of the method for estimating the transfer function of the present invention;

[0037] Figure 4 This is a flowchart of the method for estimating the transfer function of the present invention.

[0038] Explanation of reference numerals in the attached figures

[0039] 1. Vibrator; 2. Sound sensor; 3. Volumetric sound source; 4. Speaker; 5. Wheel axle head. Detailed Implementation

[0040] To better understand the above-mentioned objectives, features, and advantages of the present invention, the present invention will be described in detail below with reference to the accompanying drawings and specific embodiments. It should be noted that, unless otherwise specified, the embodiments and features described in these embodiments can be combined with each other.

[0041] In the description of this invention, it should be noted that the terms "center," "upper," "lower," "left," "right," "vertical," "horizontal," "inner," and "outer," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, or the orientation or positional relationship commonly used when the product of this invention is in use. They are only for the convenience of describing this invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this invention. In addition, the terms "", "", "third", etc., are only used to distinguish descriptions and should not be construed as indicating or implying relative importance.

[0042] Furthermore, terms such as "horizontal" and "vertical" do not imply that components must be absolutely horizontal or suspended, but rather that they can be slightly tilted. For example, "horizontal" simply means that its direction is more horizontal than "vertical," not that the structure must be completely horizontal, but can be slightly tilted.

[0043] In the description of this invention, it should also be noted that, unless otherwise explicitly specified and limited, the terms "set," "install," "connect," and "link" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection of two components. Those skilled in the art can understand the specific meaning of the above terms in this invention based on the specific circumstances. Example

[0044] like Figure 2 and Figure 3 As shown, a transfer function estimation device for an active road noise control system includes a vibrator 1, an acceleration sensor, a sound sensor 2, a volumetric sound source 3, and a data acquisition system. The force sensor of the vibrator 1 is attached to the wheel axle head 5, and the acceleration sensor is attached to one side of the force sensor to obtain the relative phase information of the force sensor. The sound sensor 2 is located inside the vehicle, the volumetric sound source 3 is connected to a speaker 4, and the data acquisition system is connected to the volumetric sound source 3, the vibrator 1, and the sound sensor 2. The data acquisition system is used to collect signals emitted by the sound sensor 2, the vibrator 1, the acceleration sensor, the volumetric sound source 3, and the speaker 4.

[0045] The number and arrangement of the sound sensors 2 correspond to the requirements of the road noise active control system. In this implementation, there are four sound sensors 2. Example

[0046] like Figure 3 and Figure 4 As shown, a transfer function estimation method for an active road noise control system includes the following steps:

[0047] S1: Obtain the acoustic-vibration frequency response function matrix;

[0048] S2: Obtain the acoustic frequency response function matrix;

[0049] S3: Superimpose the obtained acoustic frequency response function matrices and assign the superimposed result to S(z) to obtain the transfer function between the antiphase acoustic wave and the residual signal;

[0050] S4: Superimpose the obtained acoustic-vibration frequency response function matrices, assign the superimposed result to P(z), and obtain the transfer function between the reference signal and the residual signal;

[0051] S5: Call the required transfer function according to different road noise active control system architectures.

[0052] S1 includes:

[0053] S11: Input a burst of random white noise signal into exciter 1;

[0054] S12: The data acquisition system synchronously acquires signals from sound sensor 2, exciter 1 and accelerometer, and processes the signals to obtain the acoustic-vibration frequency response function between the excitation point of exciter 1 and each sound sensor 2.

[0055] S13: Repeat S11 and S12 to measure the acoustic-vibration frequency response function between the exciter 1 and each sound sensor 2 in sequence, so as to obtain the acoustic-vibration frequency response function matrix.

[0056] S2 includes:

[0057] S21: Place the volumetric sound source 3 at the mounting point of one of the speakers 4, and arrange the sound sensor 2 inside the vehicle;

[0058] S22: Input a burst of random white noise signal into volumetric sound source 3;

[0059] S23: The data acquisition system synchronously acquires the signals emitted by the sound sensor 2 and the volumetric sound source 3, processes them, and obtains the sound-sound frequency response function between the excitation point of the volumetric sound source 3 and each sound sensor 2.

[0060] S24: Repeat steps S11, S12 and S13 to measure the sound-sound frequency response function of each speaker 4 mounting point in turn to obtain the sound-sound frequency response function matrix. In this embodiment, there are four speakers 4.

[0061] The embodiments given above are preferred examples for implementing the present invention, and the present invention is not limited to the above embodiments. Any non-essential additions or substitutions made by those skilled in the art based on the technical features of the present invention are within the protection scope of the present invention.

Claims

1. A transfer function estimation method for an active road noise control system, wherein the method is implemented using a transfer function estimation device for the active road noise control system, characterized in that: The device includes a vibrator (1), an acceleration sensor, a sound sensor (2), a volume sound source (3), and a data acquisition system. The data acquisition system is used to acquire signals emitted by the sound sensor (2), the vibrator (1), the acceleration sensor, the volume sound source (3), and the speaker (4). The force sensor of the exciter (1) is fixedly connected to the wheel axle head (5), and the acceleration sensor is located on one side of the force sensor to obtain the relative phase information of the force sensor. The sound sensor (2) is installed inside the vehicle, the volume sound source (3) is connected to the speaker (4), and the data acquisition system is connected to the volume sound source (3), the vibrator (1) and the sound sensor (2). The sound sensor (2) is provided with four; The method includes the following steps: S1: Obtain the acoustic-vibration frequency response function matrix; S2: Obtain the acoustic frequency response function matrix; S3: Superimpose the obtained sound-to-sound frequency response function matrices to obtain the transfer function between the antiphase sound wave and the residual signal; S4: Superimpose the obtained acoustic-vibration frequency response function matrices to obtain the transfer function between the reference signal and the residual signal; S5: Call the required transfer function according to different road noise active control system architectures; The steps for obtaining the acoustic-vibration frequency response function matrix include: S11: Input a burst of random white noise signal into the exciter (1); S12: The data acquisition system synchronously acquires signals from the sound sensor (2), the exciter (1) and the accelerometer, and processes the signals to obtain the acoustic-vibration frequency response function between the excitation point of the exciter (1) and each sound sensor (2); S13: Repeat S11 and S12 to measure the acoustic-vibration frequency response function between the exciter (1) and each sound sensor (2) in turn to obtain the acoustic-vibration frequency response function matrix; The steps for obtaining the acoustic frequency response function matrix include: S21: Place the volumetric sound source (3) at the mounting point of one of the speakers (4) and arrange the sound sensor (2) inside the vehicle; S22: Input a burst of random white noise signal into the volumetric sound source (3); S23: The data acquisition system synchronously acquires the signals emitted by the sound sensor (2) and the volume sound source (3), processes them, and obtains the sound-sound frequency response function between the excitation point of the volume sound source (3) and each sound sensor (2); S24: Repeat steps S21, S22 and S23 to measure the acoustic frequency response function of each loudspeaker (4) installation point in turn to obtain the acoustic frequency response function matrix; The sound-to-sound frequency response function matrix obtained in S3 is superimposed, and the superimposed result is assigned to S(z) to obtain the transfer function between the antiphase sound wave and the residual signal. The acoustic-vibration frequency response function matrices obtained in S4 are superimposed, and the superimposed result is assigned to P(z) to obtain the transfer function between the reference signal and the residual signal.

2. The transfer function estimation method for an active road noise control system according to claim 1, characterized in that: The acceleration sensor is glued to one side of the force sensor, and the force sensor is glued to the wheel axle head (5).

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