Sound source positioning method and device, and storage medium

Abstract

The invention discloses a sound source positioning method and device, and a storage medium. The embodiment of the invention discloses a sound source recognition method and device, equipment and a storage medium, and the method comprises the steps: obtaining environment sound pressure through at least two piezoelectric vibrators; calibrating the environment sound pressure obtained by each piezoelectric vibrator based on the adjustment coefficient of each piezoelectric vibrator to obtain the target sound pressure of each piezoelectric vibrator; the target sound pressure of each piezoelectric vibrator is converted into the distance between each piezoelectric vibrator and a sound source according to the relation that the sound pressure changes along with the distance; and determining the position of the sound source based on the position of each piezoelectric vibrator and the distance between each piezoelectric vibrator and the sound source.

Description

Technical Field

[0001] The present application relates to the field of sound recognition technology, and in particular to a sound source recognition method, device, equipment and storage medium. Background Art

[0002] At present, the automobile industry is showing a development trend of electrification, networking, sharing and intelligence, which has put forward new technical requirements for vehicle driving methods, user interaction experience, vehicle usage mode, etc., and it is urgent to improve the technology of the current vehicle system to meet these requirements. As a sensor, the external microphone needs to be placed outside the vehicle to support different application scenarios, such as external voice interaction, external voice vehicle control, external noise pickup for noise reduction inside and outside the vehicle, internal and external voice interaction, etc., and voice recognition technology is a technology that converts sound signals into digital signals and identifies the type and content of the sound through a series of algorithm analysis. The technology includes voice recognition, voice synthesis, voice analysis, voice conversion, etc. In the related technology, due to the limitation of vehicle waterproof and dustproof, the installation position of the external microphone is limited, the sound collection position is relatively single, the signal-to-noise ratio of the acquired sound signal is not high, and it is not possible to obtain sound signals at multiple locations to meet the user's experience needs. Summary of the invention

[0003] Another object of the present invention is to provide a sound source identification method, which has the advantage of obtaining ambient sound pressure through at least two piezoelectric vibrators; calibrating the ambient sound pressure obtained by each piezoelectric vibrator based on the adjustment coefficient of each piezoelectric vibrator to obtain the target sound pressure of each piezoelectric vibrator; utilizing the relationship between sound pressure and distance, converting the target sound pressure of each piezoelectric vibrator into the distance between each piezoelectric vibrator and the sound source; and determining the position of the sound source based on the position of each piezoelectric vibrator and the distance between each piezoelectric vibrator and the sound source.

[0004] Another object of the present invention is to provide a sound source identification method, which has the advantage of adjusting the ambient sound pressure obtained by each piezoelectric vibrator by obtaining the adjustment coefficient of each piezoelectric vibrator, so that the adjusted ambient sound pressure has the same noise sound pressure, which makes it easier to perform denoising and obtain better denoising effect.

[0005] Another object of the present invention is to provide a sound source identification method, which has the advantage of determining the adjustment coefficient of each piezoelectric vibrator by using the acquired standard noise sound pressure and the noise sound pressure acquired by each piezoelectric vibrator.

[0006] Another object of the present invention is to provide a sound source identification method, which has the advantage that by respectively mounting at least two piezoelectric vibrators on the diaphragms at different positions of the vehicle panel, the adjustment coefficient of the piezoelectric vibrator mounted on the corresponding diaphragm can be changed by adjusting the material of the diaphragm. At the same time, the distance between each two piezoelectric vibrators is greater than the preset distance to obtain a better positioning effect.

[0007] Another object of the present invention is to provide a sound source identification method, which has the advantage that for each piezoelectric vibrator, the change in sound pressure is determined based on preset sound pressure parameters and the adjusted ambient sound pressure, and then the distance between the piezoelectric vibrator and the sound source is obtained based on the change in sound pressure.

[0008] Another object of the present invention is to provide a sound source identification method, which has the advantage of determining a circle with each piezoelectric vibrator as the center and the distance between each piezoelectric vibrator and the sound source as the radius, and determining the intersection of the circles corresponding to each piezoelectric vibrator, and the intersection located outside the vehicle is the sound source position.

[0009] Another advantage of the present invention is that it provides a sound source identification method, which performs denoising processing based on the adjusted ambient sound pressure of at least two piezoelectric vibrators to obtain corresponding voice data, performs voice recognition based on the voice data to obtain a recognition result, and interacts based on the voice recognition result and the position of the sound source to obtain a better interaction effect.

[0010] Another object of the present invention is to provide a sound source identification method, which has the advantage of performing differential processing on the adjusted ambient sound pressure of at least two piezoelectric vibrators to eliminate the common noise part and obtain relatively pure voice data.

[0011] Another object of the present invention is to provide a sound source identification device, which has the advantage that the sound source identification device includes a piezoelectric array microphone, a control module and a diaphragm, the piezoelectric array microphone is mounted on the diaphragm at different positions on the vehicle panel, and the control panel is used to implement the above-mentioned method steps to receive sounds emitted from multiple directions, and then determine the position information of sound sources located at different positions of the vehicle.

[0012] Another object of the present invention is to provide an electronic device, which has the advantage that the electronic device includes a memory and a processor, the memory stores a computer program that can be run on the processor, and the processor implements the steps in the above method when executing the computer program.

[0013] Another object of the present invention is to provide a computer-readable storage medium, which has the advantage of storing a computer program thereon, and is characterized in that when the computer program is executed by a processor, the steps in the above method are implemented.

[0014] To achieve the above purpose, the technical solution of the embodiment of the present application is implemented as follows:

[0015] On the one hand, an embodiment of the present application provides a sound source identification method, the method comprising:

[0016] Acquire the ambient sound pressure through at least two piezoelectric vibrators; calibrate the ambient sound pressure acquired by each piezoelectric vibrator based on the adjustment coefficient of each piezoelectric vibrator to obtain the target sound pressure of each piezoelectric vibrator; utilize the relationship between the change of sound pressure and distance to convert the target sound pressure of each piezoelectric vibrator into the distance between each piezoelectric vibrator and the sound source; determine the position of the sound source based on the position of each piezoelectric vibrator and the distance between each piezoelectric vibrator and the sound source.

[0017] On the other hand, an embodiment of the present application provides a sound source identification device, including a piezoelectric array microphone, a control module and a diaphragm, wherein the piezoelectric array microphone is mounted on the diaphragm at different positions on the vehicle panel, and the control panel is used to implement the steps of the above method.

[0018] On the other hand, an embodiment of the present application provides an electronic device, including a memory and a processor, wherein the memory stores a computer program that can be executed on the processor, and the processor implements the steps in the above method when executing the computer program.

[0019] On the other hand, an embodiment of the present application provides a computer-readable storage medium having a computer program stored thereon, wherein the computer program implements the steps in the above method when executed by a processor.

[0020] It should be understood that the above general description and the following detailed description are merely exemplary and explanatory, and are not intended to limit the technical solutions of the present application. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Figure 1A A schematic top view of a vehicle external sound source recognition system provided in an embodiment of the present application;

[0022] Figure 1B A flow chart of a sound source identification method provided in an embodiment of the present application;

[0023] Figure 2 A flow chart of a sound source identification method provided in an embodiment of the present application;

[0024] Figure 3 A flow chart of a sound source identification method provided in an embodiment of the present application;

[0025] Figure 4 A flow chart of a sound source identification method provided in an embodiment of the present application;

[0026] Figure 5 A flow chart of a sound source identification method provided in an embodiment of the present application;

[0027] Figure 6 A flow chart of a sound source identification method provided in an embodiment of the present application;

[0028] Figure 7a-7c A schematic diagram of the structure of a piezoelectric vibrator provided in an embodiment of the present application;

[0029] Figure 8 This is a schematic diagram of a signal input structure of a single piezoelectric microphone according to an embodiment of the present application;

[0030] Fig. 9 A schematic diagram of the structure of a piezoelectric microphone vibrator provided in an embodiment of the present application;

[0031] Fig.10 A schematic diagram of a piezoelectric microphone vibrator array structure provided in an embodiment of the present application;

[0032] Fig.11 A schematic diagram of the structure of a piezoelectric microphone combination method provided in an embodiment of the present application;

[0033] Fig.12 A schematic diagram of the structure of a piezoelectric microphone combination method provided in an embodiment of the present application;

[0034] Fig.13 A schematic diagram of a noise elimination method provided in an embodiment of the present application;

[0035] Fig.14 A schematic diagram of a method for determining a sound source position provided in an embodiment of the present application;

[0036] Fig.15 A schematic diagram of a method for detecting a sound source position when the sound source volume changes provided in an embodiment of the present application;

[0037] Fig.16 A schematic diagram of the structure of a sound source identification device provided in an embodiment of the present application;

[0038] Fig.17 A hardware entity diagram of a computer device provided in an embodiment of the present application. DETAILED DESCRIPTION

[0039] In order to make the purpose, technical solutions and advantages of the present application clearer, the technical solutions of the present application are further elaborated in detail below in conjunction with the drawings and embodiments. The described embodiments should not be regarded as limiting the present application. All other embodiments obtained by ordinary technicians in the field without making creative work are within the scope of protection of the present application.

[0040] In the following description, reference is made to "some embodiments", which describe a subset of all possible embodiments, but it is understood that "some embodiments" may be the same subset or different subsets of all possible embodiments, and may be combined with each other without conflict. The terms "first / second / third" involved are merely used to distinguish similar objects and do not represent a specific order for the objects. It is understood that "first / second / third" may be interchanged in a specific order or sequence where permitted, so that the embodiments of the present application described herein can be implemented in an order other than that illustrated or described herein.

[0041] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as those commonly understood by those skilled in the art to which this application belongs. The terms used herein are only for the purpose of describing this application and are not intended to limit this application.

[0042] The embodiment of the present application provides a method for localizing a sound source, and more particularly, relates to a method for localizing a sound source using a vehicle-mounted piezoelectric microphone, which identifies the location of the sound source through the vehicle-mounted piezoelectric microphone and simultaneously recognizes the voice of the sound source, thereby supporting human-vehicle interaction. The method can be executed by a processor of a computer device. The computer device may refer to a server, a laptop, a tablet computer, a desktop computer, a smart TV, a set-top box, a mobile device (such as a mobile phone, a portable video player, a personal digital assistant, a dedicated messaging device, a portable gaming device), and other devices with data processing capabilities.

[0043] In some embodiments, when the car is used as a vehicle that can interact with the outside world, microphones need to be installed on different sides of the outside of the vehicle. Figure 1A It is a top view schematic diagram of vehicle external sound source recognition in some embodiments of the present application. The position of the external sound source is determined by an external microphone. Exemplarily, microphones 1, 2, and 3 are installed around the vehicle. The position of sound source 1 can be determined by microphones 1 and 2, and the position of sound source 2 can be determined by microphones 2 and 3.

[0044] Figure 1B A flow chart of a sound source identification method provided in an embodiment of the present application is shown as follows: Figure 1B As shown, the method includes the following steps S101 to S104:

[0045] S101. Acquire ambient sound pressure through at least two piezoelectric vibrators.

[0046] In an embodiment of the present application, at least two of the piezoelectric vibrators can be mounted on the diaphragm at different positions on the vehicle panel, such as the B-pillar of the vehicle or behind the front and rear bumpers. The specific installation position can be determined according to actual needs and application scenarios, and is not limited in the embodiment of the present application.

[0047] Based on the above embodiments, by installing the piezoelectric vibrator at multiple positions, it is possible to more conveniently obtain sound pressure signals from all directions, and is no longer limited to obtaining sound pressure from only fixed positions, thereby improving the user experience and the sound reception effect.

[0048] In some embodiments, when the piezoelectric vibrator is installed behind the window glass, glass can be used as the diaphragm. When the piezoelectric vibrator is installed on the outer shell of the vehicle, a plastic shell can be used as the diaphragm. The specific diaphragm type can vary with the material type of the installation position of the piezoelectric vibrator, which is not limited here. For example, a dedicated diaphragm can be used, which has a better sound reception effect and higher sensitivity. The softness of the diaphragm is positively correlated with the sensitivity.

[0049] Based on the above embodiment, directly installing the microphone on the back of the vehicle body structure can make minimal changes to the vehicle structure, ensuring the sealing of the vehicle body. Compared with traditional vehicle-mounted microphones, it has better dust and water resistance. The use of a dedicated diaphragm can further improve the microphone's sound reception effect and improve sensitivity. The diaphragm can be made of more durable automotive-grade materials, and the user experience is better than ordinary waterproof films.

[0050] In the embodiment of the present application, the distance between each two piezoelectric vibrators is greater than the preset distance. In some embodiments, the distance between each two piezoelectric vibrators is not less than 3 cm. Too small a distance between piezoelectric vibrators will lead to inaccurate recognition of the sound source position, so a minimum distance is set to ensure good recognition accuracy.

[0051] In an embodiment of the present application, the ambient sound pressure may be a collection of multiple sounds, such as human voices, bird calls, and the sound of cars driving. Of course, it may also include other types of sounds, depending on the actual application scenario, which is not limited in the embodiment of the present application.

[0052] In some embodiments, the piezoelectric vibrator can always be in standby mode, operate at low power consumption when no sound is sensed, and continuously monitor the surrounding environment. When the ambient sound pressure is sensed, it can respond quickly and resume normal operation. In some embodiments, when the ambient sound pressure less than the preset sound pressure threshold is obtained through the piezoelectric vibrator, it can be regarded as noise sound pressure that does not contain the user's voice and discarded; when the ambient sound pressure greater than or equal to the preset sound pressure threshold is obtained, it can be considered to contain the sound of the user for subsequent processing.

[0053] Based on the above embodiments, compared with ordinary MEMS (Micro-Electro-Mechanical System) microphones, the piezoelectric vibrator microphone used in the present application does not require additional power support, and can achieve sound-to-electric conversion only by relying on its own piezoelectric effect, and has a shorter response time. Therefore, the piezoelectric microphone can work in low-power mode for a long time for monitoring, realizing all-weather rapid response to user voice to determine the location of the sound source.

[0054] S102: Calibrate the ambient sound pressure acquired by each piezoelectric vibrator based on the adjustment coefficient of each piezoelectric vibrator to obtain a target sound pressure of each piezoelectric vibrator.

[0055] In the embodiment of the present application, the adjustment coefficient of each piezoelectric vibrator is an adjustment parameter for calibrating the ambient sound pressure, which is calculated based on the standard noise parameter and the noise level obtained by the piezoelectric vibrator.

[0056] In an embodiment of the present application, after the ambient sound pressure is obtained by each of the piezoelectric vibrators, based on the method for obtaining the adjustment coefficient, when calibrating the ambient sound pressure, the adjustment coefficient can be multiplied or divided by the ambient sound pressure to obtain the calibrated ambient sound pressure, that is, the target sound pressure.

[0057] It should be noted that the above calibration operation can be an operation to amplify, reduce, or keep the acquired ambient sound pressure unchanged. The panel materials used in different positions of the vehicle are different. For different positions of the vehicle, the diaphragm material may need to be adjusted to be close to the panel material. For example, in order to ensure sealing and durability, some positions of the vehicle need to use harder materials. Here, the diaphragm material also needs to be adjusted to a harder material. The harder material diaphragm will reduce the sensitivity of the microphone. Calibration of the acquired ambient sound pressure can adjust the sound pressure level of microphones with different sensitivities, which is convenient for subsequent noise reduction and recognition processing.

[0058] S103 , using the relationship between the change in sound pressure and distance, convert the target sound pressure of each of the piezoelectric vibrators into the distance between each of the piezoelectric vibrators and the sound source.

[0059] In the embodiment of the present application, when the sound pressure level generated by the sound source remains unchanged, as the distance between the sound source and the piezoelectric vibrator increases, the sound pressure obtained by the piezoelectric vibrator will also decrease, that is, the received ambient sound pressure is negatively correlated with the distance between the piezoelectric vibrator and the sound source. Based on this relationship, the distance between the sound source and each piezoelectric vibrator can be inferred by the obtained target sound pressure. The relationship between sound attenuation with distance is relatively easy to measure, and can be adjusted accordingly for different environments. For example, high temperature and low temperature will affect the propagation of sound. In this way, the accurate relationship between sound attenuation and distance can be obtained for subsequent steps.

[0060] S104: Determine the position of the sound source based on the position of each of the piezoelectric vibrators and the distance between each of the piezoelectric vibrators and the sound source.

[0061] In the embodiment of the present application, illustratively, the position of the sound source is determined by two piezoelectric vibrators. Based on the known positions of the piezoelectric vibrators and the distance between each piezoelectric vibrator and the sound source, the position of the sound source can be determined by constructing a geometric relationship.

[0062] Exemplarily, the location of the sound source can be determined by determining a triangle. When the distance between the piezoelectric vibrators and the distance between the piezoelectric vibrators and the sound source are obtained, a unique triangle can be constructed with the two piezoelectric vibrators as the two vertices of the triangle. The position of the triangle vertices outside the vehicle is used as the position of the sound source to determine the exact position of the sound source.

[0063] In some embodiments, if the sound source position is determined by multiple piezoelectric vibrators, two piezoelectric vibrators can be selected each time to adopt the calculation method in the above example, and a more accurate sound source position can be obtained through multiple calculations. In addition, calculations can also be performed through geometric relationships of other geometric figures, which are not listed here one by one.

[0064] Based on the above embodiments, by using relatively basic geometric relationships to infer the sound source position, the complexity of the system logic operation can be greatly reduced, the operation speed can be improved, and the error of the sound source position obtained by this method is not large, and the direction of the sound source can be basically identified.

[0065] Figure 2 1 is an optional flow chart of a sound source localization method provided in an embodiment of the present application, and the method can be executed by a processor of a computer device. Figure 1B , Figure 1B Step S102 in can be updated to S201 to S202, combined with Figure 2 The steps shown are described below, and the method includes the following steps:

[0066] S101. Acquire ambient sound pressure through at least two piezoelectric vibrators.

[0067] S201 . Adjust the ambient sound pressure acquired by each piezoelectric vibrator based on the adjustment coefficient of each piezoelectric vibrator to obtain an adjusted ambient sound pressure; each of the adjusted ambient sound pressures includes the same noise sound pressure.

[0068] In some embodiments, a corresponding adjustment coefficient is individually set for each piezoelectric vibrator, and the adjustment coefficient is a parameter used to adjust the ambient sound pressure obtained by the piezoelectric vibrator.

[0069] In some embodiments, the adjustment coefficient of the piezoelectric vibrator depends on the softness of the diaphragm material at the installation site of the piezoelectric vibrator and the selected standard noise sound pressure. When other conditions remain unchanged, for example, taking a pair of piezoelectric vibrators with diaphragms of different materials as an example, it is assumed that the ambient sound pressure after adjustment = the ambient sound pressure before adjustment * adjustment coefficient. For the sake of convenience, it is assumed that the diaphragm of the first piezoelectric vibrator is harder and the diaphragm of the second piezoelectric vibrator is softer. If the noise sound pressure obtained by the first piezoelectric vibrator is taken as the standard noise sound pressure, that is, the adjustment coefficient of the first piezoelectric vibrator is 1, and the adjustment coefficient of the second piezoelectric vibrator must be less than 1 to adjust the noise sound compression obtained by the second piezoelectric vibrator to the same level as the standard noise sound pressure. consistent; if the noise sound pressure obtained by the second piezoelectric vibrator is taken as the standard noise sound pressure, that is, the adjustment coefficient of the second piezoelectric vibrator is 1, and at this time the adjustment coefficient of the first vibrator must be greater than 1, then the noise sound pressure obtained by the first piezoelectric vibrator can be adjusted to be consistent with the standard noise sound pressure; for another example, the selected standard noise sound pressure has changed, which may be due to the adjustment of the preset standard noise sound pressure value, or the reselection of the noise sound pressure of other piezoelectric vibrators as the standard noise sound pressure. At this time, the proportional relationship between the standard noise sound pressure and the noise sound pressure of each piezoelectric vibrator has changed, and the adjustment coefficient needs to be modified so that the noise sound pressure of each piezoelectric vibrator can still be consistent with the standard noise sound pressure.

[0070] In some embodiments, in order to make the sound pressure obtained by each piezoelectric vibrator contain the same level of noise pressure, so as to facilitate denoising, the sound pressure obtained by each piezoelectric vibrator needs to be adjusted. The following is an example of a piezoelectric vibrator as the adjustment object.

[0071] Exemplarily, if the noise sound pressure level contained in the ambient sound pressure obtained by the piezoelectric vibrator is greater than the standard noise sound pressure, the ambient sound pressure obtained by the piezoelectric vibrator needs to be reduced as a whole based on the adjustment coefficient so that the noise sound pressure level contained in the ambient sound pressure is the same as the standard noise sound pressure.

[0072] Exemplarily, if the noise sound pressure level contained in the ambient sound pressure obtained by the piezoelectric vibrator is lower than the standard noise sound pressure, the ambient sound pressure obtained by the piezoelectric vibrator needs to be amplified as a whole based on the adjustment coefficient so that the noise sound pressure level contained in the ambient sound pressure is the same as the standard noise sound pressure.

[0073] Exemplarily, if the noise sound pressure level included in the ambient sound pressure acquired by the piezoelectric vibrator is equal to the standard noise sound pressure, it is no longer necessary to change the ambient sound pressure acquired by the piezoelectric vibrator.

[0074] In some embodiments, the ambient sound pressure acquired by each piezoelectric vibrator includes the same level of noise sound pressure, and the same amount of noise can be removed by directly performing differential processing to obtain a relatively pure voice sound pressure signal.

[0075] For example, using two piezoelectric vibrators as an example, the noise sound pressure in the ambient sound pressure obtained by the first piezoelectric vibrator is used as the standard noise sound pressure. At this time, it is no longer necessary to adjust the ambient sound pressure obtained by the first piezoelectric vibrator. For the sound pressure obtained by the second piezoelectric vibrator, its noise sound pressure is obtained and the ratio operation is performed with the standard noise sound pressure. The operation result is used as the adjustment coefficient of the second piezoelectric vibrator, and then the ambient sound pressure obtained by the second piezoelectric vibrator is adjusted based on the adjustment coefficient of the second piezoelectric vibrator. Among them, if the noise sound pressure of the ambient sound pressure obtained by the second piezoelectric vibrator is greater than the standard noise sound pressure, the adjustment is characterized by an overall reduction in the ambient sound pressure; if the noise sound pressure is less than the standard noise sound pressure, the adjustment is characterized by an overall increase in the ambient sound pressure; if the noise sound pressure is equal to the standard noise sound pressure, the adjustment is characterized by not changing the ambient sound pressure.

[0076] Based on the above embodiments, the common noise part in the ambient sound pressure can be eliminated by adjusting the ambient sound pressure, thereby achieving a better dynamic noise elimination effect.

[0077] S202: Using the adjusted ambient sound pressure of each piezoelectric vibrator as the target sound pressure of each piezoelectric vibrator.

[0078] In some embodiments, the target sound pressure is used as the sound pressure signal finally acquired by the piezoelectric vibrator, and in subsequent processing steps, operations are performed on the target sound pressure of each piezoelectric vibrator.

[0079] S103 , using the relationship between the change in sound pressure and distance, convert the target sound pressure of each of the piezoelectric vibrators into the distance between each of the piezoelectric vibrators and the sound source.

[0080] S104: Determine the position of the sound source based on the position of each of the piezoelectric vibrators and the distance between each of the piezoelectric vibrators and the sound source.

[0081] Here, the above steps S101, S103 and S104 correspond to the above steps S103 and S104 respectively. Figure 1B When implementing the steps S101, S103 and S104, reference may be made to the specific implementation manners of the aforementioned steps S101, S103 and S104.

[0082] In an embodiment of the present application, by adjusting the ambient sound pressure and determining the distance between each vibrator and the sound source based on the adjusted ambient sound pressure combined with the changing relationship between sound pressure and distance, and then determining the position of the sound source, the sound pressure of the sound source at each azimuth position can be obtained while ensuring the sound pressure effect, and then the position of the sound source can be determined.

[0083] Figure 31 is an optional flow chart of a sound source localization method provided in an embodiment of the present application, and the method can be executed by a processor of a computer device. Figure 2 , Figure 2 Steps S301 to S302 may be added after step S101 in the above method. Figure 3 The steps shown are described below, and the method includes the following steps:

[0084] S101. Acquire ambient sound pressure through at least two piezoelectric vibrators.

[0085] S301: Obtain a standard noise sound pressure and a noise sound pressure in each of the ambient sound pressures.

[0086] In an embodiment of the present application, the standard noise sound pressure can be a preset noise sound pressure, or it can be a selected ambient sound pressure from multiple acquired ambient sound pressures and the noise sound pressure in the ambient sound pressure can be used as the standard noise sound pressure. The standard noise sound pressure can be set according to actual needs and application scenarios, and the embodiment of the present application does not limit it.

[0087] Based on the above embodiments, by flexibly selecting a suitable standard noise sound pressure, the sound distortion generated in the subsequent environmental sound pressure calibration operation can be reduced, thereby ensuring the accuracy of subsequent sound recognition.

[0088] In the embodiments of the present application, the noise sound pressure in each of the ambient sound pressures can be obtained through an ICA (independent component analysis) algorithm or a deep learning method. Any method that can obtain the noise sound pressure from the ambient sound pressure can be used in the embodiments of the present application and is not limited here.

[0089] S302: Determine an adjustment coefficient of each of the piezoelectric vibrators based on the standard noise sound pressure and the noise sound pressure acquired by each of the piezoelectric vibrators.

[0090] In an embodiment of the present application, a ratio operation is performed between the standard noise sound pressure and the noise sound pressure of each of the piezoelectric vibrators, and the calculated result is used as the adjustment coefficient of each of the piezoelectric vibrators. The order of the ratio operation is not limited here, and it is only used to obtain the size and proportional relationship between the noise sound pressure of the piezoelectric vibrator and the standard noise sound pressure, and to obtain the adjustment coefficient and calibrate the ambient sound pressure. Based on different operation orders, the operation method can be changed accordingly when the ambient sound pressure is subsequently adjusted based on the adjustment coefficient. For example, the adjustment coefficient = piezoelectric vibrator noise sound pressure / standard noise sound pressure, then the adjusted ambient sound pressure = the adjusted ambient sound pressure / adjustment coefficient.

[0091] Piezoelectric vibrators have high sensitivity, and even tiny differences in vibration can produce large results. Therefore, calculating the adjustment coefficient for each piezoelectric vibrator separately instead of using a unified adjustment coefficient to adjust all piezoelectric vibrators can make differentiated adjustments based on the tiny differences of each piezoelectric vibrator to obtain accurate sound pressure data, providing support for subsequent sound source location recognition and speech recognition.

[0092] Based on the above embodiment, by calculating the adjustment coefficient for each piezoelectric vibrator respectively, the acquired ambient sound pressure can be accurately adjusted, and the calculation method of the adjustment coefficient does not involve complex algorithms, and will not cause a large burden on the system when a large number of ambient sound pressures are involved at the same time. The adjustment coefficient can be obtained quickly, and then the ambient sound pressure can be adjusted.

[0093] S201 . Adjust the ambient sound pressure acquired by each piezoelectric vibrator based on the adjustment coefficient of each piezoelectric vibrator to obtain an adjusted ambient sound pressure; each of the adjusted ambient sound pressures includes the same noise sound pressure.

[0094] S202: Using the adjusted ambient sound pressure of each piezoelectric vibrator as the target sound pressure of each piezoelectric vibrator.

[0095] S103 , using the relationship between the change in sound pressure and distance, convert the target sound pressure of each of the piezoelectric vibrators into the distance between each of the piezoelectric vibrators and the sound source.

[0096] S104: Determine the position of the sound source based on the position of each of the piezoelectric vibrators and the distance between each of the piezoelectric vibrators and the sound source.

[0097] Here, the above steps S101, S201, S202, S103 and S104 correspond to the above steps respectively. Figure 2 When implementing the steps S101, S201, S202, S103 and S104, reference may be made to the specific implementation manners of the aforementioned steps S101, S201, S202, S103 and S104.

[0098] In the embodiment of the present application, the adjustment coefficient of each piezoelectric vibrator is calculated separately, which ensures the accuracy of the target sound pressure obtained, thereby improving the accuracy of subsequent sound source positioning. When a piezoelectric vibrator accessory in the vehicle is subsequently changed, it is only necessary to recalculate the adjustment coefficient of the piezoelectric vibrator separately, thereby improving the flexibility in the implementation of the solution.

[0099] Figure 4 1 is an optional flow chart of a sound source localization method provided in an embodiment of the present application, and the method can be executed by a processor of a computer device. Figure 1B , Figure 1B Step S103 in can be updated to S401 to S402, combined with Figure 4 The steps shown are described below, and the method includes the following steps:

[0100] S101. Acquire ambient sound pressure through at least two piezoelectric vibrators.

[0101] S102: Calibrate the ambient sound pressure acquired by each piezoelectric vibrator based on the adjustment coefficient of each piezoelectric vibrator to obtain a target sound pressure of each piezoelectric vibrator.

[0102] S401 . For each of the piezoelectric vibrators, determine a sound pressure variation based on a preset sound pressure parameter and the target sound pressure.

[0103] In the embodiment of the present application, the preset sound pressure parameter is the sound pressure at a preset distance from the sound source. Exemplarily, when the preset distance is 1m, the preset sound pressure parameter may be 66db.

[0104] In some embodiments, the sound pressure variation is the difference between a preset sound pressure parameter and a target sound pressure. The positive or negative value of the sound pressure variation can characterize whether the distance between the current sound source and the piezoelectric vibrator is within the preset distance or outside the preset distance. Exemplarily, taking the target sound pressure obtained by the piezoelectric vibrator as 60db as an example, the sound pressure variation at this time is determined to be 6db, indicating that the sound pressure is attenuated by 6db at this time, that is, the distance between the sound source and the piezoelectric vibrator is greater than 1m. Exemplarily, taking the sound pressure obtained by the vibrator as 71db as an example, the sound pressure variation at this time is determined to be -5db, indicating that the distance between the sound source and the piezoelectric vibrator is less than 1m.

[0105] In some embodiments, in addition to setting the preset distance to 1m, the sound pressure value obtained at other distances can also be selected as the preset sound pressure parameter, and the corresponding distance can be used as the preset distance. The same sound source at the same location will obtain different changes based on different preset sound pressure parameters and preset distances, but it will not affect the subsequent determination of the sound source location. The volume of sound emitted by different people is slightly different, but it is still within the normal range.

[0106] S402: Determine the distance between the piezoelectric vibrator and the sound source based on the sound pressure change.

[0107] Exemplarily, the calculation is continued with the data given in the example of step S401. First, the distance between the sound source and the piezoelectric vibrator is calculated for the case where the attenuation is 6 db. That is, at this time the distance between the sound source and the piezoelectric vibrator is 1.99m.

[0108] For example, the calculation is continued with the data given in the example of step S401, and the calculation is performed for the case where the attenuation is -5 db. At this time, the distance between the sound source and the piezoelectric vibrator is That is, at this time the distance between the sound source and the piezoelectric vibrator is 0.56m.

[0109] S104: Determine the position of the sound source based on the position of each of the piezoelectric vibrators and the distance between each of the piezoelectric vibrators and the sound source.

[0110] Here, the above steps S101, S102 and S104 correspond to the above steps S103, S104 and S105, respectively. Figure 1B Step S101, step S102 and step S104 in the embodiment may be implemented with reference to the specific implementation manners of the aforementioned steps S101, step S102 and step S104.

[0111] In the embodiment of the present application, calculations are performed based on variable preset parameters, and different calculation parameters can be set for different environments. For example, for a relatively small space, the corresponding preset parameters should also be reduced accordingly to obtain a better positioning effect. In this way, the preset parameters can be flexibly set to meet the application needs of various environments without consuming additional computing power.

[0112] Figure 5 1 is an optional flow chart of a sound source localization method provided in an embodiment of the present application, and the method can be executed by a processor of a computer device. Figure 1B , Figure 1B Step S104 in can be updated to S501 to S502, combined with Figure 5 The steps shown are described below, and the method includes the following steps:

[0113] S101. Acquire ambient sound pressure through at least two piezoelectric vibrators.

[0114] S102: Calibrate the ambient sound pressure acquired by each piezoelectric vibrator based on the adjustment coefficient of each piezoelectric vibrator to obtain a target sound pressure of each piezoelectric vibrator.

[0115] S103 , using the relationship between the change in sound pressure and distance, convert the target sound pressure of each of the piezoelectric vibrators into the distance between each of the piezoelectric vibrators and the sound source.

[0116] S501, determining a circle corresponding to each piezoelectric vibrator with the position of each piezoelectric vibrator as the center and the distance between each piezoelectric vibrator and the sound source as the radius.

[0117] In some embodiments, a method for determining the location of a sound source based on the characteristics of a circle is provided. When the distance between a piezoelectric vibrator and the sound source is known, a circle can be drawn with the piezoelectric vibrator as the center and the distance from the sound source as the radius, and the sound source can be determined to be on the circle. When two piezoelectric vibrators are used to perform the above operation, two intersections can be determined, and when the number of piezoelectric vibrators reaches three or more, a unique intersection can be determined. Using three or more piezoelectric vibrators can obtain a more accurate positioning effect, while using two piezoelectric vibrators can reduce costs while obtaining a more accurate positioning effect. In actual situations, the number of piezoelectric vibrators can be flexibly selected according to needs.

[0118] Based on the above example, the position of the sound source can be quickly obtained when the position of the piezoelectric vibrator and the distance to the sound source are known. In some environments where the accuracy requirement is not high, only two piezoelectric vibrators can be used for calculation, which can further improve the speed.

[0119] S502: Determine the position of the intersection point located outside the vehicle among the intersection points of the circles corresponding to each of the piezoelectric vibrators as the sound source position.

[0120] In the embodiment of the present application, when a person is interacting with the vehicle outside the vehicle, if the sound source position is determined by two piezoelectric vibrators, two possible sound source positions will be generated. At this time, the sound source position inside the vehicle can be excluded based on the scene of sound source position judgment, and the sound source outside the vehicle is used as the final determined true sound source position. The vehicle body is relatively simple to determine whether the sound source is inside or outside the vehicle, so the situation where the sound source is inside the vehicle can be excluded when only two piezoelectric vibrators are used, and the actual sound source position can be quickly and accurately obtained.

[0121] Here, the above steps S101, S102, and S103 correspond to the above steps respectively. Figure 1B When implementing steps S101, S102 and S103, reference may be made to the specific implementation manners of the aforementioned steps S101, S102 and S103.

[0122] In an embodiment of the present application, the number of piezoelectric vibrators enabled for each positioning operation can be selected based on the positioning accuracy requirements, and a distinction can be made between the sounds inside and outside the vehicle to prevent misidentification of the voices of people inside the vehicle, misjudgment of their positions, or misoperation, or even danger.

[0123] Figure 6 1 is an optional flow chart of the sound source localization method provided in the embodiment of the present application, and the method can be executed by a processor of a computer device. Figure 1B , Figure 1B Steps S601-S603 can be added after step S104 in Figure 6The steps shown are described below, and the method includes the following steps:

[0124] S101. Acquire ambient sound pressure through at least two piezoelectric vibrators.

[0125] S102: Calibrate the ambient sound pressure acquired by each piezoelectric vibrator based on the adjustment coefficient of each piezoelectric vibrator to obtain a target sound pressure of each piezoelectric vibrator.

[0126] S103 , using the relationship between the change in sound pressure and distance, convert the target sound pressure of each of the piezoelectric vibrators into the distance between each of the piezoelectric vibrators and the sound source.

[0127] S104: Determine the position of the sound source based on the position of each of the piezoelectric vibrators and the distance between each of the piezoelectric vibrators and the sound source.

[0128] S601 , performing denoising processing based on target sound pressures of at least two piezoelectric vibrators to obtain speech data corresponding to the sound source.

[0129] In some embodiments, a spectrum analysis method may be used to analyze the sound pressure signal to obtain the frequency band where the noise is located, and then a filter corresponding to the frequency band may be set to filter the sound pressure signal to remove the noise.

[0130] In some embodiments, differential processing may also be used for denoising. In which, step S601 includes:

[0131] Step S6011: Perform differential processing on the target sound pressures of at least two of the piezoelectric vibrators to obtain voice data corresponding to the sound source.

[0132] In an embodiment of the present application, after obtaining the target sound pressure of at least two piezoelectric vibrators, the target sound pressure is differentially processed to eliminate the common noise portion in each target sound pressure, and the difference signal is retained as the input of the human voice, and the retained human voice input is used as the speech data corresponding to the sound source.

[0133] Based on the above embodiments, by eliminating the common noise portion in the target sound pressure through differential processing, a relatively pure voice signal can be obtained, so that the system has a better recognition effect on the user's instructions to provide corresponding services or perform specified operations. Differential processing is a currently mature processing method and does not require the additional development of new noise reduction methods, thereby reducing development costs.

[0134] S602: Perform speech recognition based on the speech data to obtain a recognition result.

[0135] In an embodiment of the present application, after acquiring the voice data, the voice data is recognized to determine the semantics and other information of the voice data. Signal processing technology, acoustic feature extraction technology, acoustic model processing technology, voice model technology and other channels can be used to recognize the voice data. A suitable recognition method can be selected according to actual needs. As long as the method can obtain the result of voice recognition, it can be used in this embodiment and is not limited here.

[0136] In some embodiments, the accuracy and safety of vehicle voice recognition can be improved by pre-recording voice models of the vehicle owner and / or user preset persons. Unrecorded human voices can be marked as failing voice recognition in the recognition results, while recorded human voices such as the vehicle owner's voice can pass voice recognition.

[0137] Based on the above example, by obtaining voice data for recognition, it is possible to meet the user's usage needs while not responding to strangers' voices, preventing the vehicle from being stolen or dangerous by others. It only responds to pre-stored human voices, ensuring the safety of vehicle use and improving the user experience in many ways.

[0138] S603: interact based on the recognition result and the position of the sound source.

[0139] In an embodiment of the present application, after obtaining the voice recognition result, the vehicle can take corresponding actions based on the voice recognition result. For example, when the user says "open the trunk", the vehicle can open the trunk after recognizing the voice data to interact with the user. For another example, when the user says "open the door", the vehicle can open the door closest to the user based on the recognized position of the person.

[0140] In some embodiments, after recognizing the user's voice, the user is also supported to interact with the in-vehicle artificial intelligence such as ChatGPT, for example, querying weather information, road information, etc. through voice.

[0141] Based on the above embodiments, by combining the user's location for interaction, the use of the car is made intelligent, which can greatly improve the user experience in some cases where manual operation is inconvenient for some users. In addition, combined with artificial intelligence, it can have a better recognition effect on the instructions given by the user, and can meet the user's more diverse voice commands during the interaction.

[0142] Here, the above steps S101, S102, S103 and S104 correspond to the above steps respectively. Figure 1B Steps S101, S102, S103 and S104 in the embodiment may be implemented with reference to the specific implementation manners of the aforementioned steps S101, S102, S103 and S104.

[0143] In the embodiment of the present application, not only the position of the user when the voice is uttered is determined, but also the user's voice is recognized, and then interaction is performed based on the user's position, thereby realizing intelligent vehicle control.

[0144] The following is an explanation of an exemplary application of the embodiments of the present application in a practical application scenario.

[0145] With the development of intelligent connected cars, vehicles are increasingly in need of intelligent voice interaction capabilities with the outside world. As a sensor, the external microphone needs to be placed outside the car to support different application scenarios, such as external voice interaction, external voice vehicle control, external noise pickup for noise reduction inside and outside the car, and voice interaction inside and outside the car. However, the waterproof and dustproof level of current on-board microphones is very low, basically failing to meet the requirements of IP67 (i.e., it does not have a high level of waterproof and dustproof capabilities). In fact, there are currently no standard requirements for the installation of external microphones, but different manufacturers often require at least IP67 levels. IP67 means that the device has level 6 dustproof and level 7 waterproof capabilities. IP67-level devices can protect against dust ingress (overall contact prevention and dust penetration protection), and can also protect against short-term liquid immersion, with a maximum of 30 minutes of anti-immersion capabilities in water with a depth of 15 cm to 1 meter. In actual use, various extreme situations need to be considered. For example, in daily rainy days, IP67 can basically meet the waterproof level requirements of the microphone. However, during the car washing process, the IP67-rated microphone equipment cannot withstand the impact of a high-pressure water gun.

[0146] In fact, IP68 is the highest level in terms of dustproof and waterproof. The 8 in IP68 means that it can withstand immersion in water when submerged, and can be used continuously for a period of time in water at a certain depth. However, there is no clear regulation on the depth or time, which is generally determined by the manufacturer. In other words, it can be soaked in water at a depth of 1.5 meters for half an hour without damage, and it is still called IP68 if it exceeds this standard. Some IP68 products even require normal use for more than 10 hours at a depth of 100 meters, so there is no upper limit to the IP68 waterproof capability. Therefore, it is meaningless to define IP68, but there are clear regulations for IP69K. IP69K refers to the ability to withstand the hot steam scour test defined in EN60529 and DIN 40050-9. IP69K means that while completely preventing dust intrusion, it can withstand high-pressure and high-temperature water / steam cleaning, and the equipment can still operate normally. It can provide protection against water pressure of 100 bar (1450 psi) and temperature of 80°C. The pressure is applied directly to the equipment at 30 degree angles (0, 30, 60 and 90 degrees) for 30 seconds at each angle for a total of two minutes to prevent water ingress.

[0147] However, supporting IP69K does not mean supporting IP68. The biggest significance of IP69K is high temperature protection (for example, in winter in the north, high-pressure water guns can be high-temperature hot water) and high-pressure impact waterproofing (not long-term immersion waterproofing). For microphone equipment outside the car, if the impact of high-pressure water guns is taken into consideration, it is necessary to support IP67 and IP69K requirements.

[0148] The best water pressure for car washing is generally between 40bar and 80bar. When washing a car with a higher water pressure, the paint surface of the car may be damaged due to the high pressure, causing certain damage to the surface of the car. Most IP67 waterproof structural designs use waterproof sealing foam or waterproof glue sealant (waterproof sealing between shells), but waterproof sealing foam or waterproof glue sealant will cause the sound of the electroacoustic device to not pass through the shell after the electronic product is sealed. If waterproof membrane materials (waterproof breathable membrane\waterproof sound-permeable membrane) are used to achieve waterproof and breathable, it is necessary to open air holes or sound-permeable holes on the shell to achieve air permeability and sound permeability. The waterproof membrane materials (waterproof breathable membrane\waterproof sound-permeable membrane) of electronic products on the market currently have the functions of dustproof and waterproof, air permeability and pressure balance, as well as moisture-proof exhaust and cooling and heat dissipation. However, waterproof membrane materials alone are not enough, because the requirements of automotive-grade applications, especially on the outside of the car body, are not suitable for covering with waterproof membrane materials alone. Even IP69K materials cannot guarantee their aging characteristics. Therefore, the outdoor microphones on the market are basically installed inside the exterior rearview mirror and equipped with a waterproof membrane, which can prevent dust while also avoiding the impact of rain and water guns.

[0149] When a car is used as a vehicle that can interact with the outside world, microphones need to be installed on different sides of the outside of the vehicle. Considering the waterproof level requirements, there is currently no suitable installation location for the microphone. The usual way is to install the microphone inside the exterior rearview mirror. The problem with this is that the direction of the outside person's speech should be close to the direction of the exterior rearview mirror. In addition, when the exterior rearview mirror is replaced with a smaller exterior rearview camera, it is impossible to install an exterior microphone. At the same time, other locations of the vehicle, such as the front and rear, still need to install exterior microphones to support voice input from different directions outside the vehicle. In order to solve the above problems, the embodiments of the present disclosure provide a microphone that does not require a pickup hole but can still pick up sounds outside the vehicle, thereby solving problems such as waterproofing, dustproofing, and corrosion resistance, and at the same time determining the position of the speaker.

[0150] In the embodiment of the present application, the microphone utilizes the piezoelectric characteristics of the piezoelectric vibrator. When there is air vibration outside the vehicle, the piezoelectric vibrator will sense the vibration caused by the diaphragm through its back diaphragm and convert the vibration signal into an electrical signal, which is the input microphone audio signal. Among them, through the array mode of multiple piezoelectric vibrators, the following characteristics can be achieved: 1. The sampling sound frequency of the piezoelectric microphone is wider (compared to traditional microphones) 2. Better resistance to environmental noise level (based on the capabilities of the microphone array) 3. Waterproof, dustproof, and high temperature resistant 4. Lower cost (multiple microphone arrays can still use one ECU), better scalability 5. No need for complex microphone mounting brackets 6. Support sound positioning 7. With sound wake-up function (can work in low power mode), it can be awakened by external sound. When the external sound pressure exceeds the threshold, the microphone component is actively awakened, and the microphone component can wake up the vehicle ECU to work.

[0151] In some embodiments, the car microphone can be installed in the internal structure of the car panel, supporting the appropriate position of the car voice interaction, such as the side of the car, the plastic back panel of the B-pillar or C-pillar, and the rear of the car can also be installed in the appropriate position of the rear box tail, etc. These positions can be installed with diaphragms of similar material structures, and because the diaphragms are directly facing the outside, they can be waterproof and dustproof, and the appearance is basically the same.

[0152] In some embodiments, the installation methods include: 1. Mounted behind the diaphragm, the structural components of the diaphragm and the piezoelectric vibrator are installed outside the car and seamlessly spliced ​​with the external panel. The diaphragm is made of special materials, and the color and appearance are consistent with the surrounding materials, but the diaphragm material has better receiving sensitivity and can better receive the sound outside the car. This diaphragm material is usually not a metal material, and it would be more appropriate to use a softer material. 2. Mounted behind the window glass, the piezoelectric vibrator is mounted on the back of the window, so that the external sound will vibrate the glass, and the glass will transmit the vibration to the piezoelectric vibrator. The piezoelectric vibrator converts the pressure vibration into an electrical signal, and the piezoelectric vibrator microphone module can resolve the piezoelectric signal into a sound audio signal. Usually, due to the thick thickness of the glass, its signal receiving sensitivity is not high enough, so the final sound signal-to-noise ratio is not good enough, affecting the receiving effect. Therefore, verification and calibration are required, installed in a suitable position, and the signal-to-noise ratio is improved through the microphone array. However, due to the poor signal-to-noise ratio of the environment outside the car itself, the voltage obtained by the piezoelectric vibrator will be lower through the glass diaphragm with lower sensitivity. 3. Mounted behind the plastic panel outside the car, the piezoelectric vibrator can be directly mounted behind the B-pillar or the front and rear bumpers outside the car. When encountering a panel with a harder material, the signal reception sensitivity will be insufficient, so the final sound signal-to-noise ratio is not good enough, affecting the reception effect. Therefore, verification and calibration are required, and the signal-to-noise ratio is improved through the microphone array.

[0153] like Figure 7a-7c As shown, Figure 7a-7c The voltage generated by the medium-pressure electric vibrator changes accordingly when it is deformed. The piezoelectric vibrator is very sensitive and can sense very slight vibration pressure. It converts the vibration pressure into an electrical signal, thus converting the captured vibration signal into an acoustic electrical signal. Figure 7a When the piezoelectric vibrator 71 is stretched, the voltmeter 72 detects a reverse voltage. Figure 7b The piezoelectric vibrator 73 is not deformed, and the voltmeter 74 shows that no voltage is generated. Figure 7c The piezoelectric vibrator 75 is compressed, and the voltmeter 76 detects a forward voltage.

[0154] Among them, the piezoelectric vibrator converts sound into electric energy through the piezoelectric effect. When the piezoelectric ceramic sheet is subjected to external pressure, the ceramic sheet undergoes mechanical changes, and its polarization strength decreases, causing a portion of the charge attached to the surface of the ceramic sheet to be released, resulting in a discharge phenomenon. When the pressure is removed, it returns to its original state, the polarization strength increases, and a portion of the charge is adsorbed on the electrode again, resulting in a charging phenomenon. This phenomenon of converting mechanical energy into electrical energy is called the "positive piezoelectric effect." Positive piezoelectric effect: When subjected to external force, the polarization of the piezoelectric body changes and releases corresponding electrical energy, and the released electrical energy is proportional to the applied force. Therefore, after selecting the piezoelectric vibrator, the piezoelectric vibrator is mounted on the back of the external diaphragm (the hard protective film on the panel). Figure 8-10 As shown, Figure 8 It is a schematic diagram of the signal input structure of a single piezoelectric microphone, wherein 81 is the positive voltage output and 82 is the negative voltage output; Fig. 9 It is a schematic diagram of the structure of a piezoelectric microphone vibrator assembly, where only one piezoelectric microphone vibrator is installed on the diaphragm panel; Fig.10 It is a schematic diagram of a piezoelectric microphone vibrator array structure, in which two piezoelectric microphone vibrators are installed on the same diaphragm panel.

[0155] In some embodiments, the function of the piezoelectric microphone array back component is to parse the analog voltage signal of the microphone into an audio signal and output it to other ECU modules in the vehicle through the I2S (Inter IC Sound) bus, also known as the integrated circuit built-in audio bus.

[0156] like Figure 11-12 As shown, Fig.11 It is a schematic diagram of the structure of a piezoelectric microphone combination method, in which a back plate assembly is not provided for each piezoelectric vibration microphone; Fig.12 This is a schematic diagram of the structure of another piezoelectric microphone combination method, in which a back plate component is provided for each piezoelectric microphone.

[0157] In some embodiments, not every piezoelectric microphone assembly requires a backplate assembly. The backplate assembly may be integrated into other ECU modules, or all piezoelectric microphone assemblies may share one backplate assembly. In this way, the analog signal on each piezoelectric microphone assembly will be connected to other ECU modules or one of the backplate assemblies.

[0158] like Fig.13 As shown, Fig.13 is a schematic diagram of a noise elimination method. Fig.13 Taking two piezoelectric microphones as an example, it is demonstrated how to adjust the received ambient sound pressure, which is explained below in conjunction with an embodiment.

[0159] In some embodiments, the sound pressure signal can be processed by the following method. The principle of piezoelectric microphone array signal processing is to perform differential processing on a single microphone signal, obtain a difference signal as the input of the human voice, and eliminate other signals as external noise. The premise of this is that the horizontal distance between each microphone needs to be far enough, for example, not less than 3 cm. When the diaphragm materials used by microphone 1 and microphone 2 are different, the sound pressure received at the microphone end for the same external sound pressure will be different. The softer the diaphragm material, the higher the sensitivity of the microphone, that is, the higher the sound pressure received. The harder the diaphragm material, the lower the sensitivity of the microphone, that is, the lower the sound pressure received. Therefore, the sound pressure level of the microphone can be adjusted at this time, such as increasing or decreasing the sound pressure Z received by microphone 2. When the noise sound pressure level X of microphone 2 is 噪 The noise sound pressure level Y of microphone 1 噪 When the adjustment coefficient of microphone 2 is a=Y 噪 / Z 噪 , then the modulated sound pressure of microphone 2 is X=a*Z. Through differential processing, the pressure difference XY of the two microphones can be obtained at this time. The pressure difference is the voice pressure difference D of the person outside the car, that is, a*ZY, where. The voice sound pressure Y received by microphone 1 is the sound pressure received by the person outside the car when speaking at a specific position outside the car. The voice sound pressure X received by microphone 2 is the sound pressure received by the person outside the car when speaking at the same position, that is, X=Y+D=a*Z. Through the above method, the receiving sensitivity of the microphone can be improved. The main method is to use the modulated sound pressure amplitude to eliminate common noise and parse the human voice sound pressure input of different microphones. The advantage of this method is that it has better dynamic characteristics, and when there is a large range of random noise outside, it can do better dynamic noise elimination.

[0160] The microphone receiving sensitivity can be improved by the method in the above embodiment. The main method is to use the modulated sound pressure amplitude to eliminate common noise and analyze the human voice sound pressure input of different microphones. The advantage of this method is that it has better dynamic characteristics and can perform better dynamic noise elimination when there is a large range of random noise outside.

[0161] like Fig.14 As shown, Fig.14 The present invention is a schematic diagram of a method for determining the location of a sound source. The specific method is described below in conjunction with an embodiment.

[0162] In some embodiments, the position of the sound source can be determined by the following method: when microphone 1 and microphone 2 are in the same environment, it can be assumed that the noise environment is basically the same, so only the change in the position of the speaker will cause the sound pressure to be different on different microphones. The louder the sound pressure of the person outside the vehicle, the greater the sound pressure received by the microphone. When the person outside the vehicle speaks at the same sound pressure level, the closer to the vehicle, the closer the sound pressure received by the microphone. Using the voice sound pressure intensity of the person outside the vehicle, the position of the person outside the vehicle can be located (using the intersection of the radius circle to take the intersection point). In this way, the horizontal relative position of the person outside the vehicle and the center point of microphone 1 and microphone 2 can be determined.

[0163] like Figure 1A As shown, Figure 1A The present invention is a top view schematic diagram for identifying external sound sources of a vehicle, and a specific method is described below in conjunction with an embodiment.

[0164] The specific implementation method is as follows. In order to make the scheme easier to understand, the nouns and values ​​involved in the scheme are first explained. Sound pressure level (SPL): The human ear's induction of the strength of sound is reflected by the sound pressure level, and the unit is DB. Sound pressure level: LP = 20lg (P / P0) where P is the sound pressure (Pa Pascals), P0 is the reference sound pressure, which is 2*10-5Pa. This value refers to the sound pressure of the sound with a frequency of 1000Hz when the human ear can just hear the sound, that is, the lowest sound pressure. Definition: When talking normally, the human voice power is 1uW. When speaking loudly, the human voice power can increase to 1mW, that is, the sound pressure measured at 1m is approximately 65-69dB. Sound attenuation (L): When the temperature is 20℃, the attenuation at the distance from the sound source is: L = 20lgD where: D is the front distance from the sound source (M meters). It can be deduced from this that the attenuation at 1M from the sound source is L = 20lg1 = 0dB. The attenuation at 2M is L=20lg2=6dB, and so on. In the above embodiment, the accuracy of the microphone for sound source positioning does not need to be very precise, as long as the approximate direction (distance and direction from the vehicle) is confirmed. Therefore, it can be preliminarily estimated that the speaking sound pressure of the person outside the car (at a distance of 1 meter) is 66dB (reference value). At this time, the car-end microphones at different distances can measure the input sound pressure of the speaker and are also different, so as to deduce the distance relationship with the sound source. Using the sound pressure attenuation L=20lgD, it is obtained that at 1 meter, the attenuation is 0, and the sound pressure at this time is 66dB. Therefore, when the distance is D, the sound pressure attenuation is L=LP(microphone)-66dB=20lgD, and the distance a and b of the corresponding microphone from the speaker can be obtained by measuring LP. Because the spacing c of the microphone array is a fixed value, the position relationship of the triangle abc is confirmed. It is also possible to know the direction of the person outside the car, that is, the sound source 1 of the person outside the car. This is the method of realizing vehicle positioning by microphone array positioning method.

[0165] In order to improve the accuracy of positioning outside the car, it is recommended that the distance of the microphone array outside the car should not be too small. Otherwise, due to the small distance of c, the position of the person outside the car cannot be measured (the two circles almost overlap), and only the distance between the person outside the car and the microphone can be confirmed. At this time, it is also necessary to match the distance position captured by the external camera or the external digital key.

[0166] Of course, when a person outside the vehicle stands at the position of sound source 2, the array composed of microphone 2 and microphone 3 can identify the position of the person outside the vehicle.

[0167] like Fig.15 As shown, Fig.15This is a schematic diagram of a method for detecting the location of a sound source when the volume of the sound source changes (for the sake of convenience, the distance ratios in the figure have been deformed, and the distance ratios in the figure do not represent the distance ratios in the real scene). The following method can be used to detect the different volume of different people speaking. Assuming that the person's position relative to the vehicle has not changed, that is, the location of the sound source has not changed, but the volume has changed, and the sound pressure change is △dB, then microphone 1 measures a distance change of △a from the location of the sound source, and microphone 2 measures a distance change of △b from the location of the sound source, and the corresponding calculated location of the person outside the vehicle will also change. However, this change in sound pressure has little effect on the location and orientation. For example, assuming that the distance between microphone 1 and microphone 2 is 0.05 meters, and the sound source is located between microphone 1 and microphone 2, the sound pressure of a person at a distance of 1 meter is 66dB, and the distance between the sound source and microphone 1 and microphone 2 is 1m and 1.02m respectively. It can be obtained that the sound pressure measured by microphone 1 is 66db, the sound pressure measured by microphone 2 is about 65.828db, and the distance between the sound source and the vehicle is 0.925m. If the sound pressure of the sound source increases by 2db at this time, the new distance between the sound source and microphone 1 is 0.794m, and the distance between the sound source and microphone 2 is about 0.81m. At this time, the distance between the sound source and the vehicle is 0.759m, and the distance change from the vehicle is 0.166m. It can be seen that the distance change is not large. Therefore, the sound source can still be located according to the reference volume of 66dB. The change in the volume of the human voice source has little effect on positioning. Through sound source positioning, we can know where the speaker is horizontally located, which can support more powerful speech recognition, such as better support for chatGPT (who is speaking to and where the speaker is standing). As a result, the vehicle can track the position of the speaker and output the corresponding vehicle introduction content in the corresponding side position. When the vehicle is restricted by privacy protection and the external camera cannot be used for external monitoring, better and more comfortable communication with people outside the vehicle can be achieved through sound source positioning. When there is a piezoelectric vibrator microphone array outside the car, the voice position of the person outside the car can be located and tracked in the sound field to better support external voice recognition and voice interaction. When there are multiple microphones outside the car, the external microphone can uniformly receive the ambient noise outside the car. Since the voice of the person outside the car is at a specific position, the difference of the sound input by the external microphone can modulate the speech of the person outside the car, thereby improving the signal-to-noise ratio. The difference is not obvious, and the direction can be basically recognized.

[0168] In some embodiments, the piezoelectric microphone does not require power, and uses its own piezoelectric effect to have a very short response time when sensing sound pressure. Therefore, the piezoelectric microphone can work in a low-power mode, while existing technologies, such as MEMS (Micro-Electro-Mechanical System) microphones, require power support for continuous monitoring. It can be seen that piezoelectric microphones have advantages that other microphones cannot match.

[0169] In some embodiments, the control can be performed through the following process: the microphone analog signal enters the A / D converter and is converted into a digital audio signal. The voice signal of the microphone can be obtained through noise reduction processing inside the DSP. At the same time, the DSP transmits the processed audio signal to the external ECU module. The MCU or DSP processes the sound source positioning and sends the positioning information to the vehicle module through the corresponding transceiver method (such as UART, CAN, LIN and other interfaces).

[0170] The microphone backplane array control module can also be integrated into other ECUs. Through the piezoelectric microphone array and microphone backplane array control module, as well as noise cancellation and positioning tracking, a complete piezoelectric microphone array integrated module solution is formed to support voice input in an out-of-car environment.

[0171] The methods provided in the above embodiments can solve the following problems: 1. A piezoelectric array microphone array structure for an outdoor vehicle environment is designed to support dustproof, waterproof and corrosion-resistant. 2. A noise cancellation system based on an outdoor piezoelectric vibrator microphone is designed to improve the signal-to-noise ratio, and the speaking position of a person can be determined based on multiple microphones. 3. The piezoelectric vibrator microphone has a low-power operation mode, while the piezoelectric microphone does not require a power supply, fully utilizes its own piezoelectric effect, and has a very short response time.

[0172] like Fig.16 As shown, Fig.16The present invention is a structural schematic diagram of a sound source identification device. The device comprises a piezoelectric array microphone, a control module and a diaphragm (integrated in the microphone, not shown in the figure). The piezoelectric array microphone is mounted on the diaphragm at different positions on the vehicle panel. The piezoelectric array microphone is connected to the control module. The function of the control module can be realized by a processor in a computer device; of course, it can also be realized by a specific logic circuit; in the implementation process, the processor can be a central processing unit (CPU), a microprocessor (MPU), a digital signal processor (DSP) or a field programmable gate array (FPGA), etc. The control module is used to implement some or all of the steps in the above method.

[0173] like Fig.17 As shown, an embodiment of the present application provides an electronic device 1700, including a memory 1702 and a processor 1701, wherein the memory stores a computer program that can be executed on the processor, and when the processor executes the program, some or all of the steps in the above method are implemented.

[0174] The embodiment of the present application provides a computer-readable storage medium on which a computer program is stored, and when the computer program is executed by a processor, some or all of the steps in the above method are implemented. The computer-readable storage medium can be transient or non-transient.

[0175] An embodiment of the present application provides a computer program, including a computer-readable code. When the computer-readable code is run in a computer device, a processor in the computer device executes some or all of the steps for implementing the above method.

[0176] The embodiment of the present application provides a computer program product, which includes a non-transitory computer-readable storage medium storing a computer program, and when the computer program is read and executed by a computer, some or all of the steps in the above method are implemented. The computer program product can be implemented specifically by hardware, software or a combination thereof. In some embodiments, the computer program product is specifically embodied as a computer storage medium, and in other embodiments, the computer program product is specifically embodied as a software product, such as a software development kit (SDK) and the like.

[0177] It should be noted here that the description of the various embodiments above tends to emphasize the differences between the various embodiments, and the same or similar aspects can be referenced to each other. The description of the above device, storage medium, computer program and computer program product embodiments is similar to the description of the above method embodiment, and has similar beneficial effects as the method embodiment. For technical details not disclosed in the embodiments of the device, storage medium, computer program and computer program product of this application, please refer to the description of the method embodiment of this application for understanding.

Claims

1. A sound source identification method, characterized in that: The method comprises: Acquiring ambient sound pressure through at least two piezoelectric vibrators; Calibrate the ambient sound pressure acquired by each piezoelectric vibrator based on the adjustment coefficient of each piezoelectric vibrator to obtain the target sound pressure of each piezoelectric vibrator; Using the relationship between the change in sound pressure and distance, convert the target sound pressure of each of the piezoelectric vibrators into the distance between each of the piezoelectric vibrators and the sound source; The position of the sound source is determined based on the position of each of the piezoelectric vibrators and the distance between each of the piezoelectric vibrators and the sound source.

2. The method according to claim 1, characterized in that: The step of calibrating the ambient sound pressure acquired by each piezoelectric vibrator based on the adjustment coefficient of each piezoelectric vibrator to obtain the target sound pressure of each piezoelectric vibrator includes: Adjusting the ambient sound pressure obtained by each piezoelectric vibrator based on the adjustment coefficient of each piezoelectric vibrator to obtain an adjusted ambient sound pressure; each of the adjusted ambient sound pressures includes the same noise sound pressure; The adjusted ambient sound pressure of each of the piezoelectric vibrators is used as the target sound pressure of each of the piezoelectric vibrators.

3. The method according to claim 2, characterized in that: Before calibrating the ambient sound pressure acquired by each piezoelectric vibrator based on the adjustment coefficient of each piezoelectric vibrator to obtain the target sound pressure of each piezoelectric vibrator, the method further includes: Acquiring a standard noise sound pressure and a noise sound pressure in each of the environmental sound pressures; An adjustment coefficient of each of the piezoelectric vibrators is determined based on the standard noise sound pressure and the noise sound pressure acquired by each of the piezoelectric vibrators.

4. The method according to claim 3, characterized in that The at least two piezoelectric vibrators are mounted on the diaphragm at different positions on the vehicle panel, the adjustment coefficient is related to the softness of the diaphragm, and the distance between any two of the at least two piezoelectric vibrators is greater than or equal to a preset distance.

5. The method according to claim 1, characterized in that: The method of converting the target sound pressure of each of the piezoelectric vibrators into the distance between each of the piezoelectric vibrators and the sound source by utilizing the relationship between the sound pressure and the distance includes: For each of the piezoelectric vibrators, a sound pressure variation is determined based on a preset sound pressure parameter and the target sound pressure; and a distance between the piezoelectric vibrator and a sound source is determined based on the sound pressure variation.

6. The method according to claim 1, characterized in that The determining the position of the sound source based on the position of each of the piezoelectric vibrators and the distance between each of the piezoelectric vibrators and the sound source comprises: Determine a circle corresponding to each piezoelectric vibrator with the position of each piezoelectric vibrator as the center and the distance between each piezoelectric vibrator and the sound source as the radius; The position of the intersection point located outside the vehicle among the intersection points of the circles corresponding to each of the piezoelectric vibrators is determined as the sound source position.

7. The method according to claim 1, characterized in that: The method further comprises: Performing denoising processing based on target sound pressures of at least two piezoelectric vibrators to obtain speech data corresponding to the sound source; Performing speech recognition based on the speech data to obtain a recognition result; Interaction is performed based on the recognition result and the position of the sound source.

8. The method according to claim 7, characterized in that: The denoising is performed based on the target sound pressure of at least two piezoelectric vibrators to obtain the speech data corresponding to the sound source, including: The target sound pressures of at least two of the piezoelectric vibrators are differentially processed to obtain speech data corresponding to the sound source.

9. A sound source identification device, characterized in that: It includes a piezoelectric array microphone, a control module and a diaphragm. The piezoelectric array microphone is mounted on the diaphragm at different positions on the vehicle panel. The piezoelectric array microphone is connected to the control module, wherein: The control module is used to execute the method according to any one of claims 1 to 8.

10. An electronic device, characterized in that: The method comprises a memory and a processor, wherein the memory stores a computer program executable on the processor, and the processor implements the steps of the method according to any one of claims 1 to 8 when executing the computer program.

11. A computer-readable storage medium having a computer program stored thereon, characterized in that: When the computer program is executed by a processor, the steps in the method according to any one of claims 1 to 8 are implemented.

Images