CN113488017A

CN113488017A - Active noise reduction system and vehicle for road noise

Info

Publication number: CN113488017A
Application number: CN202110766261.4A
Authority: CN
Inventors: 何剑峰; 闫占功; 宋金响; 尤里·席尔瓦; 孙晨玮; 乌伟民; 邱利利; 李健健; 洪宗洲; 栾帅奇; 全炜倬
Original assignee: Weilai Automobile Technology Anhui Co Ltd
Current assignee: Weilai Automobile Technology Anhui Co Ltd; NIO Technology Anhui Co Ltd
Priority date: 2021-07-07
Filing date: 2021-07-07
Publication date: 2021-10-08

Abstract

The application relates to an active noise reduction system for road noise and a vehicle. The noise reduction system for road noise comprises a sensor system, an acoustic acquisition system, a processor and an audio output system, wherein the acceleration signals acquired by at least part of sensors in the sensor system are also used for active suspension control; the sound signals collected by the acoustic collection system are also used for voice-related services; and the audio output system is further configured to output a multimedia audio signal. Noise reduction systems according to some examples of the present application may share existing hardware of the vehicle, thereby reducing system complexity and allowing a higher fault tolerance rate for the system compared to an independent design.

Description

Active noise reduction system and vehicle for road noise

Technical Field

The application relates to the field of active noise reduction of vehicles, in particular to an active noise reduction system and a vehicle for road noise.

Background

On a new energy pure electric vehicle, because an internal combustion engine power assembly is not arranged, the noise of an internal engine and the noise of air intake and exhaust related to the internal combustion engine also disappear. However, noise problems caused by other sources of vibration noise, such as road noise, etc., are noticeable. The traditional passive vibration isolation, sound insulation and absorption measures can improve the noise level in the vehicle in a limited range. The basic principle of the active noise reduction technology is that the anti-phase sound waves are mutually counteracted, so that the purpose of noise reduction is achieved at a specific sound field position. At present, an active noise reduction self-adaptive algorithm for road noise is developed to a certain degree, and possibility is provided for further optimizing and controlling the road noise in the electric vehicle on the basis of passive noise reduction. However, the implementation of the active noise reduction system for road noise often requires additional hardware devices, which may increase the complexity of the internal system of the vehicle, and the interference of various subsystems in the vehicle may also affect the experience. Furthermore, the additional equipment also means higher development costs.

Disclosure of Invention

The embodiment of the application provides an active noise reduction system and a vehicle for road noise, and by sharing hardware in a plurality of systems, the complexity of an internal system of the vehicle can not be increased while road noise is actively suppressed.

According to an aspect of the present application, there is provided an active noise reduction system for road noise, including: a sensor system comprising one or more sensors that pick up acceleration signals relating to road noise; an acoustic collection system comprising one or more acoustic collectors that collect sound signals; a processor configured to generate an anti-phase sound wave signal relative to a road noise according to the acceleration signal and the sound signal; and an audio output system comprising one or more speakers that output the inverse sound wave signals; wherein the acceleration signals picked up by at least some of the sensors in the sensor system are also used for active suspension control; the sound signals collected by the acoustic collection system are also used for voice-related services; and the audio output system is further used for outputting multimedia audio signals.

In some embodiments of the present application, optionally, the sensor is mechanically coupled to the suspension system, and its mounting position may be at least one of: the suspension system comprises a vehicle body side mounting point and a vibration reduction supporting tower.

In some embodiments of the present application, optionally, the sensor mounting location is calibrated based on its detectable vibration amplitude range, sensitivity to detectable road surface excitation transmission.

In some embodiments of the application, optionally, the acoustic collector is arranged in the headrest and/or in a ceiling above the headrest.

In some embodiments of the present application, optionally, the speaker is disposed at a door position and configured to output the multimedia audio signal and a portion of the inverse sound wave signal below a predetermined frequency.

In some embodiments of the present application, optionally, the audio output system further comprises one or more noise reduction speakers disposed in the headrest and/or in a ceiling above the headrest for outputting a portion of the inverted acoustic wave signal that is higher than or equal to a predetermined frequency.

In some embodiments of the present application, optionally, the noise reduction system further includes: a CAN information extraction unit connected to the CAN system and configured to extract status information; and is

The processor is configured to generate the inverse acoustic wave signal further in accordance with the status information, wherein the status information includes at least one of: the number and position information of passengers, the vehicle speed information and the door and window opening and closing information.

In some embodiments of the present application, optionally, the noise reduction system further includes: a head tracking system comprising one or more image capture devices for capturing in-vehicle images and an image recognition device that recognizes occupant head position from the in-vehicle images; and the processor is configured to generate the inverse acoustic wave signal also as a function of the head position.

In some embodiments of the present application, optionally, the head tracking system is also used to monitor driver status.

In some embodiments of the present application, optionally, the processor is further multiplexed into at least one of: the controller of audio-visual system, the controller of power amplifier, the controller of intelligent driving system, the controller of suspension system, central domain controller.

According to another aspect of the application, there is provided a vehicle comprising a noise reduction system as any of the above.

By sharing the hardware of the active noise reduction system with other systems in the vehicle, the overall complexity of each system in the vehicle is reduced, and the faults caused by interference among the systems are also reduced.

Drawings

The above and other objects and advantages of the present application will become more apparent from the following detailed description when taken in conjunction with the accompanying drawings, in which like or similar elements are designated by like reference numerals.

Fig. 1 to 3 show schematic structural diagrams of an active noise reduction system according to an embodiment of the present application.

Detailed Description

For the purposes of brevity and explanation, the principles of the present application are described herein with reference primarily to exemplary embodiments thereof. However, those skilled in the art will readily recognize that the same principles are equally applicable to all types of active noise reduction systems for road noise and vehicles incorporating the same, and that these same or similar principles may be implemented therein, with any such variations not departing from the true spirit and scope of the present application.

Fig. 1-3 respectively illustrate active noise reduction systems according to some embodiments of the present application, where fig. 2 is a simplification of fig. 1 in order to clearly illustrate the principles of the present invention, and the active noise reduction system in fig. 3 illustrates some of the necessary components. The principles of the present invention will be better illustrated hereinafter by interspersing descriptions of the examples in fig. 1-3.

An aspect of the present application provides an active noise reduction system (hereinafter referred to as a noise reduction system) for road noise. As shown in fig. 3, noise reduction system 30 includes a sensor system 302, an acoustic acquisition system 303, a processor 301, and an audio output system 304. Wherein the sensor system 302 includes one or more sensors (not shown in fig. 3, and described in connection with other examples) that pick up acceleration signals related to road noise; the acoustic collection system 303 includes one or more acoustic collectors (not shown in fig. 3, but described in connection with other examples) that collect the sound signals; the processor 301 is configured to generate an anti-phase sound wave signal relative to the road noise according to the acceleration signal and the sound signal; the audio output system 304 includes one or more speakers that output an inverted acoustic wave signal. And, the acceleration signals picked up by at least some of the sensors in the sensor system 302 are also used for active suspension control; the sound signals collected by the acoustic collection system 303 are also used for voice related services; and the audio output system 304 is also used to output multimedia audio signals.

In the example of FIG. 2, noise reduction system 20 includes the following subsystems: a sensor system 202, an acoustic acquisition system 203, a processor 201, and an audio output system 204. In addition, several optional subsystems are also shown in FIG. 2.

As shown in fig. 2, sensor system 202 of noise reduction system 20 includes a number of vibration acceleration sensors (referred to herein simply as sensors) that are mechanically coupled to a suspension system (not shown in fig. 2) so that acceleration signals resulting from the movement of the wheels on the road surface may be picked up. On the other hand, since the road noise is also caused by motion, these acceleration signals are also associated with the road noise, and thus can be used as basic data for reducing the road noise.

Acceleration signals picked up by at least some of the sensors in sensor system 202 are also used for active suspension control. For example, the illustrated

sensors

2021, 2022 are already in the original design of the vehicle (not equipped with a noise reduction system) and are used for active suspension control. In some examples, the acceleration signals picked up by the

sensors

2021, 2022 can also be used to suppress road noise, and thus the

sensors

2021, 2022 are common to both the active suspension control system and the noise reduction system 20. In some examples, the sensor 2023 is introduced to further improve noise reduction. At this point, the sensor 2023 may be calibrated to be sensitive to vibration frequencies, and thus the signal it picks up is more suitable for use in suppressing road noise.

In some examples, the existing sensor 2022 in the original design of the vehicle model may also be calibrated to be sensitive to vibration amplitude, so that the signal it picks up is more suitable for suspension control. At this point, the only sensor that the active suspension control system shares with noise reduction system 20 will be sensor 2021.

In some examples, the acceleration signals picked up by all of the illustrated

sensors

2021, 2022, … …, 2023, while being input signals for active suspension control, are also used to suppress road noise. In this way, the sensor system 202 will be maximally shared.

In some embodiments of the present application, the sensor mounting locations described above may be body side mounting points of a suspension system, a shock absorbing support tower, or the like. According to an actual vehicle calibration result, 4-8 sensors may be needed for the whole vehicle.

In some embodiments of the present application, the sensor mounting locations described above are calibrated based on the range of sensor detectable vibration amplitudes, the sensitivity of detectable road surface excitation transmission. For example, to maximize the sensors in the common sensor system 202, the position of each sensor may be calibrated based on the range of detectable vibration amplitudes (e.g., on the bearings) and the sensitivity of detectable road surface excitation transfer simultaneously, such that a balance point can be found between the two (range of detectable vibration amplitudes, sensitivity of detectable road surface excitation transfer).

The arrangement of the sensor system 101 is shown in the noise reduction system 10 of FIG. 1, with only two sensors of the sensor system 101 being shown for illustrative purposes. As shown, where the suspension system 1012 is interposed between the tire 1011 and the subframe 1013, the

sensors

1014, 1015 may be mechanically coupled to the suspension system 1012 to pick up acceleration signals related to road noise. The picked up signals will be sent to the processor 103 for performing noise suppression.

Returning to fig. 2, acoustic collection system 203 of noise reduction system 20 includes one or more acoustic collectors disposed within the headrest and/or within the ceiling above the headrest. As shown in fig. 2, the

acoustic collectors

2031, 2032, … …, 2033 are arranged in the headrest and/or in the ceiling above the headrest for collecting sound signals. The sound signals collected by the

acoustic collectors

2031, 2032, … …, 2033 in the acoustic collection system 203 are also used for voice-related services, for example, they can be used for voice recognition, car-machine conversation, hands-free conversation, etc. A specific example of the acoustic collector may be a microphone or the like.

In some embodiments of the present application, in some high-end vehicle models, an acoustic collector may be arranged in the headrest of each passenger position and in the ceiling above the headrest, thereby making it possible to collect the sound signal of each passenger position and also providing the possibility of road noise suppression for each passenger position.

The noise reduction system 10 of fig. 1 shows an acoustic collection system composed of

acoustic collectors

1091 and 1092, in which the

acoustic collectors

1091 and 1092 are disposed in headrests of a driver seat and a passenger seat, respectively. Due to the close arrangement to the occupant, the

acoustic collectors

1091 and 1092 can more clearly collect the sound of the occupant, so that the accuracy of speech recognition can be improved, for example. Further, the sound signals collected by the

acoustic collectors

1091 and 1092 will be input to the processor 103 as residual noise for adaptive feed-forward noise reduction by the noise reduction system 10. Although the figures show one acoustic collector for each occupant position, more acoustic collectors may be arranged for each occupant or some of the occupant positions. For example, an additional acoustic collector may be disposed in the ceiling above the headrest of the driving seat, thereby further improving the voice recognition and noise suppression effects of the driving seat.

Returning to fig. 2, processor 201 of noise reduction system 20 is configured to generate an anti-phase acoustic wave signal with respect to road noise from the acceleration signal from sensor system 202, the sound signal from acoustic collection system 203. For example, the processor 201 may execute an active noise reduction algorithm to process the input acceleration signal and the input sound signal, so as to obtain an inverse sound wave signal. Here, the generated reverse phase acoustic wave signal is in the form of an electric signal. Various types of speaker playback described below may be utilized to counteract road noise.

In addition to being used in noise reduction system 20, in some embodiments of the present application, processor 201 may also be multiplexed as a controller for a video and audio system, a controller for a power amplifier, a controller for an intelligent driving system, a controller for a suspension system, or a central domain controller. As shown in fig. 1, the processor 103 of the noise reduction system 10 may be integrated and shared with a controller of the audio/video system 104, a controller of the power amplifier 106, a controller of the smart driving system (not shown), a controller of the suspension system 1012, or a central domain controller (not shown), so as to share computing power, thereby further reducing the system development cost.

The noise reduction system 10 of fig. 1 shows a processor 103 comprising a plurality of pins, wherein an acceleration signal from the sensor system 101, a sound signal from the acoustic collection system are input, and an active noise reduction algorithm is executed by the processor 103, resulting in an inverse sound wave signal being input to the mixer 105. In the mixer 105, the input inverse sound wave signal is mixed with the audio signal from the av system 104, and then amplified by the power amplifier 106. The processed signals may be played via various speakers in the vehicle.

Returning to FIG. 2, the audio output system 204 of the noise reduction system 20 includes speakers 2041-2043 disposed at the door locations, and the speakers 2041-2043 may be configured to output antiphase sonic signals. In some examples, the audio output system 204 is also used to output multimedia audio signals. For example, the audio output system 108 shown in fig. 1 including the

speakers

1081, 1082 and the

headrest speakers

1083, 1084 is used to output signals mixed by the mixer 105 and amplified by the power amplifier 106. Of course, when the multimedia audio signal and the inverse sound wave signal are not output, the audio output system 108 may only output the inverse sound wave signal and the multimedia audio signal.

In some embodiments of the present application, the speaker is configured to output the multimedia audio signal and a portion of the inverted acoustic wave signal that is lower than a predetermined frequency. For example, the speakers 2041-2043 (or the speakers 1081, 1082) shown in fig. 2 may have good medium-low frequency response characteristics, and thus, the output multimedia audio signal and the inverted sound wave signal thereof may be utilized to cancel the medium-low frequency component of the original road noise.

In some embodiments of the present application, the audio output system further comprises one or more noise reduction speakers disposed in the headrest and/or in a ceiling above the headrest for outputting portions of the inverted acoustic wave signal that are greater than or equal to the predetermined frequency. For example, the audio output system 204 shown in fig. 2 further includes

noise reduction speakers

2044 and 2046, which are good in medium-high frequency response, and which may be disposed in the headrest, in the ceiling above the headrest, so that a portion of the inverted sound wave signal higher than or equal to a predetermined frequency (for example, 400 Hz) is played around the occupant, thereby achieving road noise suppression for the occupant area (specifically, near the ear of the occupant). In this case, the suppression is mainly directed to the medium-high frequency components in the original road noise. Of course, in some examples, it may be determined whether or not a noise reduction speaker in the headrest or in the ceiling above the headrest needs to be disposed according to the calibration result. In the example of fig. 1, the audio output system 10 includes

headrest speakers

1083, 1084 that are also used to suppress the mid-to-high frequency components of the original road noise.

In some embodiments of the present application, the noise reduction speaker is disposed in the headrest of each occupant position and/or in the ceiling above the headrest. If there is a noise reduction requirement for multiple occupants, a noise reduction speaker having a good middle-high frequency response as described above may be disposed for each occupant position, for example, in the headrest of each occupant position, in the ceiling above the headrest.

Returning to fig. 2, in some embodiments of the present application, the noise reduction system 20 further includes a CAN information extraction unit 205 connected to the CAN system. The CAN information extraction unit 205 may extract status information, which may be information on the number and position of passengers, vehicle speed information, door and window opening and closing information, and the like. At this time, the processor 201 will also generate an anti-phase acoustic wave signal according to the state information. For example, if the information extracted by the CAN information extraction unit 205 indicates that there is only one driver in the vehicle, the other passenger positions are free. At this time, the processor 201 will mainly process the sound signals collected by the acoustic collectors related to the driving position in the acoustic collection system 203 (for example, the acoustic collectors are arranged in the headrest of the driving position and in the ceiling above the headrest) according to the state information, and the inverse sound wave signals output by the audio output system 204 are also directed to the driving position (for example, the noise reduction speakers in the headrest of the driving position and in the ceiling above the headrest of the driving position of the audio output system 204 are driven to play the medium-high frequency components of the inverse sound wave signals, and the speakers of the audio output system 204 are driven to output the medium-low frequency components of the inverse sound wave signals with the driving position as the center of the sound field). For another example, the output inverted acoustic wave signal may also adjust the loudness of the finally output sound with the vehicle speed. In the example of fig. 1, the CAN information extraction unit 102 is also connected to a port of the processor 103 for transmitting status information thereto.

In some embodiments of the present application, the noise reduction system further comprises a head tracking system comprising one or more image capture devices and an image recognition device. As shown in FIG. 2, noise reduction system 20 also includes a head tracking system 206, where head tracking system 206 also includes one or more image capture devices and image recognition devices. In the example of fig. 1, head tracking system 107 includes an image capture device 1071 and an image recognition device (not shown). The image capturing device 1071 is used to capture an in-vehicle image, and the image recognizing device recognizes the head position of the occupant from the in-vehicle image. As shown, the head recognized by the image recognition device is shown, and the positions of the

ears

1072, 1073 of the head are recognized. At this time, the processor 103 will also generate an anti-phase acoustic wave signal according to the head position. Specifically, the position information of the

ears

1072, 1073 will be sent to the processor 103, whereupon the processor 103 will update in real time the transfer function from the speakers, e.g. arranged in the headrest, to the human ears, thereby adjusting the output signals of the speakers in the audio output system 108, in particular the output signals of the

headrest speakers

1083, 1084 in the audio output system 108, in accordance with the position of the

ears

1072, 1073 of the head.

In some embodiments of the present application, the head tracking system is also used to monitor driver status. For example, the state of the driver may be monitored by capturing an in-vehicle image by the image capturing device 1071 shown in fig. 1 and recognizing information such as the direction of the driver's sight line from the in-vehicle image by the image recognizing device.

Another aspect of the application provides a vehicle comprising a noise reduction system as any of the above. In the vehicle, the noise reduction system can share the original hardware equipment such as an acceleration sensor, an acoustic collector, a processor, a loudspeaker and the like, so that the interference among all subsystems in the vehicle can be reduced, and the complexity of the system in the vehicle is reduced. In addition, the sharing of hardware can also reduce the cost of development and production.

The above are merely specific embodiments of the present application, but the scope of the present application is not limited thereto. Other possible variations or substitutions may occur to those skilled in the art based on the teachings herein, and are intended to be covered by the present disclosure. In the present invention, the embodiments and features of the embodiments may be combined with each other without conflict. The scope of protection of the present application is subject to the description of the claims.

Claims

1. An active noise reduction system for road noise, comprising:

a sensor system comprising one or more sensors that pick up acceleration signals relating to road noise;

an acoustic collection system comprising one or more acoustic collectors that collect sound signals;

a processor configured to generate an anti-phase sound wave signal relative to a road noise according to the acceleration signal and the sound signal; and

an audio output system comprising one or more speakers that output the inverse sound wave signals;

wherein the acceleration signals picked up by at least some of the sensors in the sensor system are also used for active suspension control; the sound signals collected by the acoustic collection system are also used for voice-related services; and the audio output system is further configured to output a multimedia audio signal.

2. The noise reduction system of claim 1, wherein the sensor is mechanically coupled to a suspension system and may be mounted in at least one of: the suspension system comprises a vehicle body side mounting point and a vibration reduction supporting tower.

3. The noise reduction system of claim 2, wherein the sensor mounting location is calibrated based on its detectable vibration amplitude range, sensitivity of detectable road surface excitation transmission.

4. The noise reduction system of claim 1, wherein the acoustic collector is disposed within a headrest and/or within a ceiling above the headrest.

5. The noise reduction system of claim 1, wherein the speaker is disposed at a door location and is configured to output the multimedia audio signal and a portion of the inverse sound wave signal below a predetermined frequency.

6. The noise reduction system of claim 5, wherein the audio output system further comprises one or more noise reduction speakers disposed within the headrest and/or within a ceiling above the headrest for outputting portions of the inverse sound wave signal above or equal to a predetermined frequency.

7. The noise reduction system of claim 1, further comprising: a CAN information extraction unit connected to the CAN system and configured to extract status information; and is

8. The noise reduction system of claim 1, further comprising: a head tracking system comprising one or more image capture devices for capturing in-vehicle images and an image recognition device that recognizes occupant head position from the in-vehicle images; and is

The processor is configured to generate the inverse acoustic wave signal also as a function of the head position.

9. The noise reduction system of claim 8, wherein the head tracking system is further configured to monitor a driver state.

10. The noise reduction system of claim 1, wherein the processor is further multiplexed into at least one of: the controller of audio-visual system, the controller of power amplifier, the controller of intelligent driving system, the controller of suspension system, central domain controller.

11. A vehicle comprising a noise reduction system as claimed in any one of claims 1-10.