Active noise reduction method for characteristic peak value of automobile road noise and vehicle

Abstract

The application discloses an active noise reduction method for characteristic peaks of automobile road noise and a vehicle, and relates to the technical field of automobile road noise control. First, a sample vehicle road noise is tested, characteristic peaks of the road noise are analyzed, a transmission path is checked according to a sorting result of the characteristic peaks of the road noise, and a path contribution of the characteristic peaks of the road noise is analyzed; a component mode of the sample vehicle is tested, and component modal frequencies are analyzed; the modal frequencies of the screened components are compared with the characteristic peak contribution sorting, whether the components are coupled is detected, the coupling is recorded with the path and the component, and the uncoupled path is sorted again according to the contribution; meanwhile, coupled components, main path vibrations and target position noise data are collected, multiple coherence of the vibration and the noise signal is calculated, a reference signal combination is screened out through sorting analysis, road noise simulation is carried out, and a real vehicle is debugged. The application has high reference signal quality, good durability and safety, ideal road noise peak reduction effect, improved noise reduction performance of the system, better stability and wide application prospect.

Description

Technical Field

[0001] This invention relates to the field of automotive road noise control technology, specifically to an active noise reduction method and vehicle targeting the characteristic peak values ​​of automotive road noise. Background Technology

[0002] Road noise in automobiles is generated by wind shearing in at high speeds and by road surface input, tire response, and suspension-induced noise from the vehicle body. To improve driving quality and ride comfort, noise reduction is necessary. Existing noise reduction technologies on the market have the following problems:

[0003] (1) Road noise active noise reduction reference signal sensor layout scheme: There are many path coupling sources at the chassis suspension rods or body attachment points, resulting in low reference signal quality.

[0004] (2) Due to installation location limitations, all use triaxial acceleration sensors and there are a large number of them, resulting in low durability.

[0005] (3) The noise reduction effect of peak road noise is not ideal.

[0006] (4) The reference signal sensor is only used for active noise reduction, and its utilization rate is not high.

[0007] To address the aforementioned issues, it is essential to develop an active noise reduction method and vehicle specifically targeting the peak characteristics of road noise. Summary of the Invention

[0008] To address the shortcomings of existing technologies, the present invention aims to provide an active noise reduction method and vehicle for targeting the characteristic peaks of road noise in automobiles. The method is simple in structure, reasonable in approach, has high reference signal quality, high durability and safety, ideal noise reduction effect on road noise peaks, good stability, high utilization rate, and is easy to promote and use.

[0009] To achieve the above objectives, the present invention is implemented through the following technical solution: an active noise reduction vehicle for road noise characteristic peaks, comprising a vehicle body, wherein the vehicle body consists of a filtering algorithm that generates noise reduction signals by receiving and processing various input signals, a reference signal for identifying characteristic frequencies, an error signal for identifying the amplitude of characteristic frequencies, a control signal for system warning, and a noise reduction signal for canceling road noise characteristic peaks, wherein the reference signal is shared with the active suspension control.

[0010] Preferably, the reference signal includes the damping spring body, engine compartment frame beam, vehicle floor, partial roof, tailgate, front and rear subframes, roof crossbeam, engine compartment front bulkhead, and powertrain mounting active end, and the reference signal is configured to collect vehicle body vibration.

[0011] Preferably, the filtering algorithm is configured to generate a control signal source for canceling noise based on the reference signal, the error signal, and the control signal; the error signal is configured to be passenger noise acquisition; the control signal is configured to be vehicle status information input; and the noise reduction signal is configured to be noise output from the vehicle speaker.

[0012] The active noise reduction method targeting the characteristic peaks of vehicle road noise comprises the following steps:

[0013] (1) First, a preliminary test of road noise was conducted on the prototype vehicle. The noise data of the passenger position inside the vehicle was tested. Rough road, smooth road surface and urban road were selected, and the working conditions from 40km / h to 100km / h (interval of 20km / h) were tested respectively.

[0014] (2) Process and analyze the peak values ​​of road noise characteristics at each passenger position of the prototype vehicle, determine the main peak values ​​of each road surface and each working condition, and sort the main characteristic peak values ​​according to the frequency of road surface and working condition usage scenarios and the subjective evaluation results of road noise characteristic peak values.

[0015] (3) According to the ranking of road noise characteristic peaks, the transmission path of the main road noise characteristic peaks is investigated, and the contribution of the road noise characteristic peak path is analyzed by OTPA (operating condition transmission path analysis), ODS (operating deformation mode) and conventional testing methods.

[0016] (4) Test the modal characteristics of the prototype vehicle components, including the sensor arrangement components included in the reference signal;

[0017] (5) Analyze the modal frequencies of the components and select those that are consistent with the peak frequency of road noise characteristics;

[0018] (6) Compare the modal frequencies of the selected components in step (5) with the peak contribution ranking of the path noise characteristics in step (3) to detect whether the components are modally coupled: the frequency coupling of the two will record the path and the component, and at the same time, the remaining uncoupled paths will be re-sorted according to the contribution.

[0019] (7) Simultaneously collect vibration signals of coupling components, select vibration signals of the main path and noise signals of passenger positions in the vehicle, select rough road, smooth road surface and urban road, and test the working conditions from 40km / h to 100km / h (interval of 20km / h);

[0020] (8) Process and calculate the multicoherence between vibration signals and noise signals;

[0021] (9) Sort them according to the main peak or main frequency band coherence, take the top 8 as the pick-up points of reference signal data, analyze and screen out the reference signal combination, and formulate multiple combination schemes.

[0022] (10) Input the reference signal and error signal data collected in step (7) of each combination scheme into the algorithm to simulate the active noise reduction performance of the road noise characteristic peak.

[0023] (11) Verify the performance of each combination scheme, the stability of road noise characteristic peak noise reduction, and the system stability on a real vehicle.

[0024] Preferably, the subjective evaluation result of the road noise characteristic peak in step (2) is obtained by professional engineers through subjective evaluation and statistics of the road noise of the prototype vehicle, which is used as a basis for the importance of the road noise characteristic peak.

[0025] As a preferred option, in step (6), the contribution of the uncoupled analysis reordered paths is selected as 1-3 main paths as reference signal layout positions based on their importance, and their selection priority is lower than that of the coupled components.

[0026] As a preferred option, step (9) optimizes the number of reference signals, reduces the position of other peak contribution reference signal picking points according to the importance of peaks, and formulates multiple combination schemes.

[0027] The beneficial effects of this invention are: the reference signal quality is high, the utilization rate and durability are high, the noise reduction effect of the road noise peak is ideal, the road noise characteristic peak coherence is high, which greatly improves the noise reduction performance of the system, has better stability, and has broad application prospects. Attached Figure Description

[0028] The present invention will now be described in detail with reference to the accompanying drawings and specific embodiments;

[0029] Figure 1 This is a schematic diagram of the active noise reduction vehicle structure for the peak value of road noise characteristics of the present invention.

[0030] Figure 2 This is a schematic diagram showing the arrangement of the reference signals in this invention;

[0031] Figure 3 This is a flowchart of the active noise reduction method for the characteristic peak value of vehicle road noise according to the present invention. Detailed Implementation

[0032] To make the technical means, creative features, objectives and effects of this invention easier to understand, the invention will be further described below in conjunction with specific embodiments.

[0033] Reference Figure 1-3This specific embodiment adopts the following technical solution: an active noise reduction vehicle targeting the peak value of road noise characteristics includes a vehicle body 1. The vehicle body 1 consists of a filtering algorithm 2 that generates a noise reduction signal by processing and calculating various input signals, a reference signal 3 for identifying characteristic frequencies, an error signal 4 for identifying the amplitude of characteristic frequencies, a control signal 5 for system warning, and a noise reduction signal 6 for canceling the peak value of road noise characteristics. The reference signal 3 is configured for vehicle vibration acquisition and can be shared with active suspension control. The error signal 4 is configured for passenger noise acquisition. The control signal 5 is configured for vehicle status information input. The filtering algorithm 2 is configured to generate a control signal source for canceling noise based on the reference signal 3, the error signal 4, and the control signal 5. The noise reduction signal 6 is configured for noise output from the vehicle speaker.

[0034] It should be noted that the reference signal 3 includes a damping spring body 301, a cabin frame beam 302, a vehicle floor 303, a partial roof 304, a tailgate 305, front and rear subframes 306, a roof crossbeam 307, a cabin front bulkhead 308, and a powertrain suspension active end 309.

[0035] This specific implementation proposes an active noise reduction method targeting the characteristic peak of vehicle road noise, the steps of which are as follows:

[0036] (1) First, a preliminary test of the road noise of the prototype vehicle was conducted, and the noise data of the passenger position inside the vehicle was tested. Rough roads, smooth roads and urban roads were selected, and the operating conditions from 40km / h to 100km / h (interval of 20km / h) were tested respectively. In addition, professional engineers conducted a subjective evaluation and statistical analysis of the road noise of the prototype vehicle, which was used as a basis for the importance of the peak value of road noise characteristics.

[0037] (2) Process and analyze the peak values ​​of road noise characteristics at each passenger position of the prototype vehicle, determine the main peak values ​​of each road surface and each working condition, and sort the main characteristic peak values ​​according to the frequency of road surface and working condition usage scenarios and the subjective evaluation results of road noise characteristic peak values.

[0038] (3) According to the ranking of road noise characteristic peaks, the transmission path of the main road noise characteristic peaks is investigated, and the contribution of the road noise characteristic peak path is analyzed by OTPA (operating condition transmission path analysis), ODS (operating deformation mode) and conventional testing methods.

[0039] (4) Test the modal characteristics of the prototype vehicle components, including the sensor arrangement components included in reference signal 3;

[0040] (5) Analyze the modal frequencies of the components and select those that are consistent with the peak frequency of road noise characteristics;

[0041] (6) Compare the modal frequencies of the components screened in step (5) with the peak contribution ranking of the path noise characteristics in step (3) to detect whether the components are modally coupled: the frequency coupling of the two will record the path and the component, and at the same time, the remaining uncoupled paths will be re-sorted according to the contribution amount. The contribution amount of the re-sorted uncoupled paths will be analyzed, and 1-3 main paths will be selected as reference signal 3 layout scheme positions according to their importance. Their selection priority is lower than that of coupled components.

[0042] (7) Simultaneously collect vibration signals of coupling components, select vibration signals of the main path and noise signals of passenger positions in the vehicle, select rough road, smooth road surface and urban road, and test the working conditions from 40km / h to 100km / h (interval of 20km / h);

[0043] (8) Process and calculate the multicoherence between vibration signals and noise signals;

[0044] (9) Sort them according to the main peak or main frequency band coherence, take the top 8 as the pick-up points of the reference signal data, and analyze and screen the reference signal combination; if you want to optimize the number of reference signals, reduce the contribution of other peaks according to the importance of the peaks, and formulate multiple combination schemes.

[0045] (10) Input the reference signal 3 and error signal 4 data collected in step (7) of each combination scheme into the algorithm to simulate the active noise reduction performance of the road noise characteristic peak.

[0046] (11) Verify the performance of each combination scheme, the stability of road noise characteristic peak noise reduction, and the system stability on a real vehicle.

[0047] It is worth noting that step (3) includes, but is not limited to: confirming based on path and response: for example, the subframe path is determined by subframe modal testing, the NTF (acoustic transfer function) value of the subframe mounting pad path, and combined with OTPA results to jointly determine the noise peak contribution path; at the response coupling end, the panel modality, panel NTF results, and panel ODS results can be combined to select points. Based on the in-vehicle noise peak characteristic analysis path and the main contribution location of the panel response, the main contribution paths and response locations are filtered and sorted.

[0048] In this specific implementation, vibration and in-vehicle noise are collected simultaneously from the main paths and response locations selected in steps (4) and (5). For example, there are 2 vehicle body transmission paths, 2 spring damping paths, 2 tailgate response paths, and 2 front and rear crossbeams of the sunroof, totaling 8 paths. This will collect vibration at 8 locations and noise at each passenger location in the vehicle at the same time.

[0049] In addition, step (7) involves collecting data and selecting a combination of reference signals. After the combination is confirmed, the resulting combined reference signal (vibration) and target noise signal (noise) are input into the algorithm for simulation. Step (8) describes the correlation between multiple reference signals and multiple target signals at various frequency points. Vibrations along each path and vibrations at the coupling position of the panel are used as reference signals, and passenger noise inside the vehicle is used as the target signal for multicoherence calculation. In MATLAB, the Mscohere function can be used for calculation. First, some invalid signals are eliminated according to the multicoherence algorithm, and then signals with high coherence are input into the proof model for calculation. This reduces the computational load of the algorithm, improves efficiency, and does not affect the simulation structure.

[0050] This specific implementation analyzes the importance of key passenger locations and significant road noise peaks based on the vehicle road noise problem. For example, in a certain vehicle, the 40Hz road noise at the driver's position has a significant subjective and objective impact, while 80Hz has a secondary impact; the 100Hz road noise at the rear passenger position has a significant impact, while 40Hz has a secondary impact, with the driver's 40Hz being the most important. First, multicoherence calculations are performed on the driver's 40Hz, and the top three combinations are selected for simulation. Because there are certain differences between actual debugging and simulation, the best simulation result may not be the best in reality. Then, important frequencies at other positions are calculated to obtain combinations. Since the number of reference signals cannot be infinite, the range of reference signals is narrowed by combining the results of important frequencies at the above important positions. For example, there are 2 paths for the subframe, 1 path for the door, and 1 path for the front crossbeam. Two positions are selected, and the frequencies of interest can be calculated comprehensively (40Hz for the front row and 100Hz for the rear row), and 2-3 sets of solutions are selected for actual vehicle debugging.

[0051] This specific implementation is applicable to common operating conditions such as constant speed driving, conventional highways, and urban roads. Its technical advantages are: ① The road noise active noise reduction reference signal sensor is arranged on the road noise peak mode coupling component, with fewer coupling from other noise sources and high reference signal quality; ② Each sensor is mainly placed inside the vehicle or engine compartment, ensuring high durability and safety; ③ There are few space restrictions on the installation of the component where the road noise peak mode is located, allowing the use of single sensors to reduce costs; ④ The reference signal sensor is arranged on the longitudinal or transverse beams, which can be shared by the active suspension, improving utilization efficiency; ⑤ The road noise characteristic peak has high coherence, greatly improving the noise reduction performance and stability of the system, and has broad market application prospects.

[0052] The foregoing has shown and described the basic principles, main features, and advantages of the present invention. Those skilled in the art should understand that the present invention is not limited to the above embodiments. The embodiments and descriptions in the specification are merely illustrative of the principles of the invention. Various changes and modifications can be made to the invention without departing from its spirit and scope, and all such changes and modifications fall within the scope of the present invention as claimed. The scope of protection of this invention is defined by the appended claims and their equivalents.

Claims

1. An active noise reduction method for road noise characteristic peaks of a vehicle, the active noise reduction method being used to reduce noise in a vehicle, the vehicle comprising a vehicle body (1), the vehicle body (1) comprising a filtering algorithm (2) for generating a noise reduction signal by processing and calculating various input signals, a reference signal (3) for identifying characteristic frequencies, an error signal (4) for identifying the amplitude of characteristic frequencies, a control signal (5) for controlling system warnings, and a noise reduction signal (6) for canceling road noise characteristic peaks, wherein the reference signal (3) is shared with active suspension control, characterized in that, The noise reduction method for vehicles includes the following steps: (1) First, a preliminary test of road noise of the prototype vehicle was conducted, and the noise data of the passenger position inside the vehicle was tested. Rough road, smooth road surface and urban road were selected, and the working conditions of 40km / h to 100km / h with an interval of 20km / h were tested respectively. (2) Process and analyze the peak values ​​of road noise characteristics at each passenger position of the prototype vehicle, determine the main peak values ​​of each road surface and each working condition, and sort the main characteristic peak values ​​according to the frequency of road surface and working condition usage scenarios and the subjective evaluation results of road noise characteristic peak values. (3) According to the ranking of road noise characteristic peaks, the transmission path of the main road noise characteristic peaks is investigated, and the contribution of the road noise characteristic peak path is analyzed by working condition transmission path analysis OTPA, working deformation mode ODS and conventional test methods. (4) Test the modal characteristics of the prototype vehicle components, including the sensor arrangement components included in the reference signal (3); (5) Analyze the modal frequencies of the components and select those that are consistent with the peak frequency of road noise characteristics; (6) Compare the modal frequencies of the selected components in step (5) with the peak contribution ranking of the path noise characteristics in step (3) to detect whether the components are modally coupled: the frequency coupling of the two will record the path and the component, and at the same time, the remaining uncoupled paths will be re-sorted according to the contribution. (7) Simultaneously collect vibration signals of coupling components, select vibration signals of the main path and noise signals of passenger positions in the vehicle, select rough road, smooth road surface and urban road, and test the working conditions from 40km / h to 100km / h with an interval of 20km / h. (8) Process and calculate the multicoherence between vibration signals and noise signals; (9) Sort them according to the main peak or main frequency band coherence, analyze and screen out reference signal combinations, and formulate multiple combination schemes; (10) Input the reference signal (3) and error signal (4) data collected in step (7) of each combination scheme into the algorithm to simulate the active noise reduction performance of the road noise characteristic peak. (11) Verify the performance of each combination scheme, the stability of road noise characteristic peak noise reduction, and the stability of the system by actual vehicle testing.

2. The active noise reduction method for the characteristic peak of vehicle road noise according to claim 1, characterized in that, In step (2), the subjective evaluation result of the road noise characteristic peak is obtained by professional engineers through subjective evaluation and statistics of the road noise of the prototype vehicle, which is used as a basis for the importance of the road noise characteristic peak.

3. The active noise reduction method for the characteristic peak of vehicle road noise according to claim 1, characterized in that, In step (6), the contribution of the uncoupled analysis reordered path is used to select 1-3 main paths as reference signals based on their importance. The location of the (3) layout scheme is selected with lower priority than that of the coupled components.

4. The active noise reduction method for the characteristic peak of vehicle road noise according to claim 1, characterized in that, Step (9) Sort the data according to the main peak or main frequency band coherence, and take the top 8 as the pick-up points of the reference signal data; reduce the position of the reference signal pick-up points according to the importance of the peak, reduce the contribution of other peaks, optimize the number of reference signals, and formulate multiple combination schemes.

5. The active noise reduction method for the characteristic peak of vehicle road noise according to claim 1, characterized in that, The reference signal (3) includes a damping spring body (301), a cabin frame beam (302), a vehicle floor (303), a partial roof (304), a tailgate (305), front and rear subframes (306), a roof crossbeam (307), a cabin front bulkhead (308), and a powertrain mounting active end (309). The reference signal (3) is configured to collect vehicle body vibrations.

6. The active noise reduction method for the characteristic peak of vehicle road noise according to claim 1, characterized in that, The filtering algorithm (2) is configured to generate a control signal source to cancel noise based on the reference signal (3), the error signal (4), and the control signal (5).

7. The active noise reduction method for the characteristic peak of vehicle road noise according to claim 1, characterized in that, The error signal (4) is configured for passenger noise acquisition.

8. The active noise reduction method for the characteristic peak of vehicle road noise according to claim 1, characterized in that, The control signal (5) is configured as a vehicle status information input.

9. The active noise reduction method for the characteristic peak of vehicle road noise according to claim 1, characterized in that, The noise reduction signal (6) is configured as the noise output of the vehicle speaker.

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