Electric vehicle low speed warning sound system and method

Abstract

The present invention relates to the field of vehicle control, and discloses an electric vehicle low-speed warning sound system and method. The electric vehicle low-speed warning sound system includes: a housing, a rotating motor, a speaker and a circuit board; the speaker is connected to the housing through a rotating motor, and the rotating motor is used to drive the speaker to rotate; the circuit board is fixed in the housing, and the rotating motor and the speaker are both connected to the circuit board for communication, and the circuit board is also connected to a vehicle-mounted camera; the circuit board is used to determine the position and distance of the hearing system to be prompted from the electric vehicle based on the image information collected by the vehicle-mounted camera, and at least control the rotating motor to drive the speaker to rotate the angle, so that the sound direction of the speaker is toward the position of the hearing system to be prompted, and control the speaker to emit a warning sound matching the distance. The present invention can realize the detection of the hearing system to be prompted, and then realize directional and accurate prompting.

Description

Technical Field

[0001] The present invention relates to the field of automobiles, and in particular to a low-speed warning sound system and method for an electric vehicle. Background Art

[0002] Electric vehicles use clean energy and electricity, which reduces environmental pollution. As electric vehicles are listed as development strategies by many countries in the world, the technology of electric vehicles is developing faster and faster, and the popularity rate is increasing. However, since electric vehicles are very quiet when driving at low speeds, pedestrians outside the vehicle, especially those with hearing impairments, find it difficult to detect the approach of the vehicle, which poses a great safety hazard.

[0003] In order to solve the pedestrian safety problem caused by the low noise of electric vehicles, the low-speed warning sound system came into being. At the same time, the state promulgated GB / T_37153-2018 "Electric Vehicle Low-Speed ​​Warning Sound" to stipulate the noise limit and test method requirements for vehicles equipped with low-speed warning sound systems, which was officially implemented on July 1, 2019. However, facing different groups of people to be warned, such as individuals at different distances or heights, if the same parameters are used for warnings, targeted and accurate warnings cannot be achieved.

[0004] In view of this, the present invention is proposed. Summary of the invention

[0005] In order to solve the above technical problems, the present invention provides an electric vehicle low-speed warning sound system and method, which can realize the detection of the hearing system to be prompted, and then achieve directional and accurate prompts.

[0006] The embodiment of the present invention provides an electric vehicle low-speed warning sound system, comprising: a housing, a rotating motor, a speaker, a circuit board, a sound sensor, a movable bracket, a slider and a fixed bracket;

[0007] The speaker is connected to the housing through the rotating motor, and the rotating motor is used to drive the speaker to rotate; the circuit board is fixed in the housing, the rotating motor and the speaker are both connected to the circuit board for communication, and the circuit board is also connected to the vehicle camera;

[0008] The circuit board is used to determine the position and distance of the hearing system to be prompted from the electric vehicle based on the image information collected by the vehicle-mounted camera, and at least control the rotary motor to drive the speaker to rotate an angle so that the sound output direction of the speaker is toward the position of the hearing system to be prompted, and control the speaker to emit a prompt sound matching the distance;

[0009] The sound sensor is fixed in the placement hole of the shell through a bracket, and the end surface of the sound sensor is on the same plane as the end surface of the placement hole;

[0010] The sound sensor is connected to the circuit board;

[0011] The sound sensor is used to measure the environmental noise around the electric vehicle, obtain noise information, and transmit it to the circuit board;

[0012] The circuit board is used to determine the noise spectrum at the position of the hearing system to be prompted based on the noise information, the position of the sound sensor and the position of the hearing system to be prompted, and determine the prompt sound parameters that are different from the noise spectrum;

[0013] The housing is fixed to the slider via the movable bracket, the slider is slidably connected to the fixed bracket, and the fixed bracket is used to fix the system to the body of the electric vehicle;

[0014] The slider is also connected to the circuit board;

[0015] The circuit board is also used to control the slider to drive the housing to slide based on the position and distance of the hearing system to be prompted from the electric vehicle, so as to drive the speaker to slide synchronously.

[0016] The embodiment of the present invention further provides a method for low-speed warning sound of an electric vehicle, which is executed based on the above-mentioned low-speed warning system of the electric vehicle; the method comprises:

[0017] Obtain image information collected by the vehicle-mounted camera;

[0018] Based on the image information, determining the position and distance of the hearing system to be prompted from the electric vehicle;

[0019] Based on the position and the distance, at least the rotary motor is controlled to drive the speaker to rotate at an angle so that the sound output direction of the speaker is toward the position of the hearing system to be prompted, and the speaker is controlled to emit a prompt sound matching the distance;

[0020] Obtain noise information collected by the sound sensor;

[0021] Determine a noise spectrum at the position of the hearing system to be prompted based on the noise information, the position of the sound sensor and the position of the hearing system to be prompted;

[0022] Based on the noise spectrum, a prompt tone parameter that is different from the noise spectrum is determined.

[0023] The embodiments of the present invention have the following technical effects:

[0024] The electric vehicle low-speed warning sound system includes a shell, a rotating motor, a speaker and a circuit board; the speaker is connected to the shell through a rotating motor, and the rotating motor is used to drive the speaker to rotate; the circuit board is fixed in the shell, and the rotating motor and the speaker are both connected to the circuit board for communication, and the circuit board is also connected to the vehicle-mounted camera; the circuit board is used to determine the position and distance of the hearing system to be prompted from the electric vehicle based on the image information collected by the vehicle-mounted camera, and at least control the rotating motor to drive the speaker to rotate the angle so that the sound direction of the speaker is toward the position of the hearing system to be prompted, and control the speaker to emit a warning sound that matches the distance. It can be combined with the vehicle-mounted camera and the circuit board to realize the position and distance detection of the hearing system to be prompted, and then realize directional and accurate prompts matching the distance according to the detected distance and position. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] In order to more clearly illustrate the specific implementation methods of the present invention or the technical solutions in the prior art, the drawings required for use in the specific implementation methods or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are some implementation methods of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0026] Figure 1 It is a schematic diagram of the connection structure of a low-speed warning sound system for an electric vehicle provided by an embodiment of the present invention;

[0027] Figure 2 It is a hardware structure diagram of a low-speed warning sound system for an electric vehicle provided by an embodiment of the present invention;

[0028] Figure 3 It is a structural schematic diagram of a first shell in the electric vehicle low-speed warning sound system provided by an embodiment of the present invention;

[0029] Figure 4 It is a structural schematic diagram of a second shell in the electric vehicle low-speed warning sound system provided by an embodiment of the present invention;

[0030] Figure 5 It is a three-dimensional structural schematic diagram of a low-speed warning sound system for an electric vehicle provided by an embodiment of the present invention;

[0031] Figure 6 A schematic diagram of a fixed bracket related structure in a low-speed warning sound system for an electric vehicle provided by an embodiment of the present invention;

[0032] Figure 7 A schematic flow chart of a method for low-speed warning sound of an electric vehicle provided in an embodiment of the present invention. DETAILED DESCRIPTION

[0033] In order to make the purpose, technical solution and advantages of the present invention clearer, the technical solution of the present invention will be described clearly and completely below. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work belong to the scope of protection of the present invention.

[0034] The electric vehicle low-speed warning sound system and method provided in the embodiments of the present invention are mainly suitable for sound prompts when the electric vehicle is driving at a low speed. Based on the detection of the hearing system to be prompted, directional and accurate prompts can be achieved to improve safety.

[0035] Figure 1 1 is a schematic diagram of a connection structure of a low-speed warning sound system for an electric vehicle provided by an embodiment of the present invention. Figure 2 Schematic diagram of the hardware structure of an electric vehicle low speed warning sound system provided by an embodiment of the present invention. Figure 1 and Figure 2 The electric vehicle low-speed warning sound system includes: a shell 11, a rotating motor 12, a speaker 13 and a circuit board 14; the speaker 13 is connected to the shell 11 through the rotating motor 12, and the rotating motor 12 is used to drive the speaker 13 to rotate; the circuit board 14 is fixed in the shell 11, and the rotating motor 12 and the speaker 13 are both communicated with the circuit board 14, and the circuit board 14 is also connected to the vehicle camera 10; the circuit board 14 is used to determine the position and distance of the hearing system to be prompted from the electric vehicle based on the image information collected by the vehicle camera 10, and at least control the rotating motor 12 to drive the speaker 13 to rotate at an angle, so that the sound direction of the speaker 13 is toward the position of the hearing system to be prompted, and control the speaker 13 to emit a warning sound matching the distance.

[0036] The housing 11 seals and protects the rotating motor 12, the speaker 13 and the circuit board 14 disposed therein, which is conducive to realizing a waterproof and dustproof structure (exemplarily described below), improving the accuracy of the prompt sound, and extending the life of the entire system.

[0037] The circuit board 14 is provided with a module with data acquisition and analysis functions such as a controller (eg, a microprocessor) to implement data analysis, processing and control.

[0038] This embodiment has the following technical effects: the circuit board 14 receives the image information collected by the vehicle camera 10, and performs image recognition to determine the position and distance of the hearing system to be prompted from the electric vehicle, and then based on this, at least the rotating motor 12 is controlled to drive the speaker 13 to rotate at an angle, so that the sound direction of the speaker 13 is toward the position of the hearing system to be prompted, and the speaker 13 is controlled to emit a prompt sound that matches the distance, and the vehicle camera 10 and the circuit board 14 can be combined to realize the position and distance detection of the hearing system to be prompted, and then the directional and accurate prompt of matching distance is realized according to the detected distance and position. Therefore, based on the image recognition technology, the position of a biological body such as a pedestrian and the distance between it and the electric vehicle are judged, and then the sound direction of the speaker 13 is intelligently adjusted, and the prompt sound matching the distance is only emitted to the area near the hearing system of the biological body, thereby reducing energy consumption and reducing environmental noise.

[0039] Specifically, the low-speed warning sound system in the related art continuously emits a warning sound within the vehicle speed range of 0-20 km / h. However, on an unmanned road, the warning sound system does not need to work. Through this embodiment, the warning sound can be intelligently turned off in the absence of a living organism, thereby reducing energy waste and noise pollution to the environment. In addition, in the presence of a living organism, the sound can only be emitted near the hearing system of the living organism, which can also reduce energy waste and environmental noise pollution, thereby saving energy and reducing environmental noise pollution.

[0040] In some embodiments, see Figure 1 and Figure 2 The electric vehicle low speed warning sound system may further include a sound sensor 15, the sound sensor 15 is connected through a bracket (reference Figure 4 The sensor bracket 150 shown in the figure is fixed in the placement hole 110 of the shell 11, and the end face of the sound sensor 15 is on the same plane as the end face of the placement hole 110; the sound sensor 15 is connected to the circuit board 14; the sound sensor 15 is used to measure the ambient noise around the electric vehicle, obtain noise information, and transmit it to the circuit board 14; the circuit board 14 is used to determine the noise spectrum at the position of the hearing system to be prompted based on the noise information, the position of the sound sensor 15 and the position of the hearing system to be prompted, and determine the prompt sound parameters that are different from the noise spectrum.

[0041] The ambient noise is measured by the sound sensor 15, and the noise condition near the hearing system to be prompted (such as the ears of pedestrians) is determined in combination with the distance. The noise condition can be represented by a noise spectrum, and the sound pressure level and frequency are further adjusted within the range required by regulations, and the speaker 13 is controlled to emit a prompt sound that exceeds the ambient noise and to which the hearing system is relatively sensitive, so that the hearing system can clearly hear the prompt sound warning.

[0042] Exemplarily, regulatory requirements may include speed-based prompt sound requirements, for example: when the forward vehicle speed is 10 km / h, the total sound pressure level of the prompt sound is not less than 52 dB (A); when the forward vehicle speed is 20 km / h, the total sound pressure level of the prompt sound is not less than 58 dB (A); when the reverse gear is 6 km / h, the total sound pressure level of the prompt sound is not less than 49 dB (A).

[0043] For example, the adjustment method of the prompt tone parameters may include: increasing the overall sound pressure level, increasing the sound frequency, and increasing the sound pressure level and the sound frequency at the same time. Specifically, the adjustment may be made based on the road conditions and vehicle conditions to improve the recognizability of the prompt tone.

[0044] In the related art, the total sound pressure level of the prompt sound (i.e., the volume of the sound) is fixed and cannot be changed according to the noise conditions of the surrounding environment. There may be excessive noise around the vehicle, and even the possibility of shielding the prompt sound. Pedestrians may not be able to hear the vehicle's prompt sound, which poses a safety risk. In this embodiment, the environmental noise is collected by a sound sensor, and the volume of the prompt sound and the magnitude of the specific frequency emitted by the system can be intelligently adjusted according to the noise conditions of the environment, thereby enhancing the magnitude of the frequency sensitive to the human ear, making it easier for pedestrians to identify and reducing safety risks.

[0045] In some embodiments, see Figure 2 and Figure 6 The electric vehicle low-speed warning sound system also includes a movable bracket 16, a slider 17 and a fixed bracket 18; the shell 11 is fixed to the slider 17 through the movable bracket 16, the slider 17 is slidably connected to the fixed bracket 18, and the fixed bracket 18 is used to fix the system to the body of the electric vehicle (for example, the center position of the front cross beam of the vehicle); the slider 17 is also connected to the circuit board 14; the circuit board 14 is also used to control the slider 17 to drive the shell 11 to slide based on the position and distance of the hearing system to be prompted from the electric vehicle, so as to drive the speaker 13 to slide synchronously.

[0046] The movable bracket 16 can be fixed to both sides of the housing 11 by bolts, and the other side of the movable bracket 16 is connected to the slider 17; a sliding motor 170 is arranged inside the slider 17 to control the slider 17 to slide left and right along the fixed bracket 18 and keep it fixed. Figure 1 The speaker 13, the rotating motor 12, the sound sensor 15 and the slider motor 170 can be connected to the circuit board 5 respectively through wires.

[0047] Among them, the fixed bracket 18 is provided with a guide groove 180, which is used for the sliding motor 170 to control the slider 17 to slide along the guide groove 180, and drive the shell 11 and the rotating motor 12, speaker 13 and other components therein to slide together; the fixed bracket 18 is fixedly installed with the body of the electric vehicle, for example, it can be installed on the front crossbeam of the vehicle.

[0048] Since the warning sound is mainly aimed at pedestrians outside the vehicle, it is necessary to control the noise impact of the warning sound device on the passengers inside the vehicle. To this end, the vibration noise generated by the warning sound system can be transmitted to the vehicle through air and structure. Vibration isolation pads (i.e., vibration isolation pads) can be installed on the fixed bracket to reduce the transmission of the vibration of the warning sound device to the vehicle.

[0049] In some embodiments, see Figure 6 A vibration isolation pad 19 may also be provided at the installation position of the fixed bracket 18 to reduce the vibration transmitted from the electric vehicle low-speed warning sound system to the front cross beam of the vehicle and reduce the impact of the warning sound on the passengers in the vehicle.

[0050] In this embodiment, the noise impact of the system on the occupants in the vehicle can be reduced by controlling the vibration and noise of the entire vehicle. Specifically, the prompt sound systems in the relevant technologies basically only meet the requirements of national regulations, and do not consider the impact on the occupants in the vehicle. Since the sound source of the prompt sound is in the medium and low frequency range of 500-1000Hz, it is easy to cause resonance of the body system and cause noise impact on the occupants in the vehicle. Therefore, in this embodiment, the transfer function from the installation position of the prompt sound system to the interior of the vehicle (such as sound transfer function, vibration transfer function, etc., considering the influence of air and structural transfer) is tested to evaluate whether the installation position is reasonable, and by adding vibration isolation pads 19, the impact of vibration on the occupants in the vehicle is reduced.

[0051] In some embodiments, in combination Figure 2 , Figure 3 and Figure 4 The shell 11 includes a first shell 111 and a second shell 112 sealed with the first shell 111; a sealing strip 1110 is set on the edge of the first shell 111 facing the second shell 112, and a groove 1120 is set on the edge of the second shell 112 facing the first shell 111; the first shell 111 and the second shell 112 are sealed by the groove 1120, and the sealing strip 1110 is filled in the gap between the first shell 111 and the second shell 112 to improve the sealing between the two shells.

[0052] The first shell 111 is located on the side of the second shell 112 away from the electric vehicle body. Based on the distance relative to the electric vehicle body, the farther first shell 111 can also be called the upper shell, and the closer second shell 112 can also be called the lower shell. A sealing strip 1110 is provided on the edge of the upper shell and installed inside the groove 1120 on the lower shell to improve the sealing performance at the sealing position of the upper shell and the lower shell, and to prevent dust and moisture from entering the interior of the shell 11.

[0053] Exemplarily, the speaker 13 can be fixed to the speaker bracket 130 by bolts, the bottom of the speaker bracket 130 is installed on the rotating motor 12, and the rotating motor 12 is fixed at the lower surface position inside the upper shell; the rotating motor 12 drives the speaker 13 to rotate, realizing up, down, left and right rotation, and the rotation angle range can be 45°, so that the speaker can emit prompt sounds at different angles.

[0054] For example, the circuit board 14 can be fixed inside the lower housing by bolts; a placement hole 110 is opened at the center of both sides of the lower housing, and the sound sensor 15 is fixed inside the lower housing by a sensor bracket 150 and placed in the placement hole 110, and the end face of the sound sensor 15 is on the same plane as the placement hole 110, so as to accurately collect environmental noise. For example, the placement hole 110 can be a circular hole, or other shapes adapted to the outer contour of the sound sensor 15, which is not limited here.

[0055] In some embodiments, a wind ball is installed on the top of the sound sensor 15, and the wind ball is used to prevent external dust and moisture from damaging the sensor, thereby ensuring the accuracy of collecting environmental noise.

[0056] In some embodiments, the shape of the first housing 111 is hemispherical (eg Figure 2 or Figure 3 As shown) or in an arc shape, and a sound hole 1111 is provided; the sound hole 1111 is used to allow the prompt sound emitted by the speaker 13 to pass through.

[0057] In this embodiment, a sound hole 1111 is provided so that the sound is emitted from the speaker 13 located in the housing 11 and then passes through the housing 11, thereby realizing a sound prompt to the organism in the environment.

[0058] In some embodiments, since the low-speed warning sound system is arranged on the outside of the electric vehicle body, dustproof and waterproof measures are required to ensure the sound efficiency while preventing the system from being damaged by dust or water, thereby ensuring its performance stability and extending its service life. An exemplary explanation is given below.

[0059] In some embodiments, see Figure 2 and Figure 3 The first shell 111 also includes a baffle 1112, which is arranged at the position of the sound hole 1111 to prevent dust and moisture from entering the shell 11; the baffle 1112 has a trumpet-shaped through hole, and the diameter of the trumpet-shaped through hole toward the outside of the shell 11 is larger than the diameter toward the inside of the shell 11.

[0060] In this embodiment, the baffle 1112 does not affect the sound passing through the shell 11 , and at the same time can prevent dust, moisture, etc. from entering the interior of the shell 11 .

[0061] In some embodiments, the baffles 1112 are semicircular in shape; when the number of the baffles 1112 is equal to or greater than two, the baffles 1112 are staggeredly distributed in the sound hole 1111 along the axial direction of the sound hole 1111 .

[0062] Exemplarily, the sound hole 1111 may be cylindrical and pass through the side wall of the housing 11; correspondingly, the baffle 1112 may be semicircular in shape and evenly spaced at 90° along the axial direction of the sound hole 1111 and cross-distributed inside the sound hole 1111; a number of trumpet-shaped through holes are provided on the baffle 1112, and the trumpet-shaped through holes have a large diameter toward the outside and a small diameter toward the speaker 13. The semicircular baffle 1112 blocks the sound hole 1111, so that dust or water vapor driven by the wind is blocked, and dust will adhere to the outward side of the baffle 1112, and water vapor will also condense on the baffle 1112. When the sound is transmitted from the speaker 13, it will be transmitted from the gap surrounded by the baffle 1112 and the sound hole 1111, so as not to affect the transmission of the sound.

[0063] By further arranging staggered baffles 1112, a curved path is formed in the sound hole 1111, further improving the effect of the baffles 1112 on dust and water vapor, but will not hinder the transmission of sound waves. Furthermore, the trumpet-shaped through hole provided on the baffle 1112 allows part of the wind carrying dust and water vapor from the outside to pass through the baffle 1112 when it moves to the baffle 1112, so as to reduce the wind noise caused by the wind resistance of the baffle 1112 to the wind. At the same time, due to the gradually reduced inner diameter of the trumpet-shaped through hole, dust or water vapor entering the through hole will be further blocked; in addition, the sound waves transmitted from the inside to the outside will also pass through the trumpet-shaped through hole, which will have an amplifying effect on the sound waves and increase the sound level.

[0064] It is understandable that the shape of the baffle 1112 can be any shape, as long as it has the effect of blocking and spoiling. The shape of the baffle 1112 is preferably semicircular, because the blocking area and the gap area of ​​a single baffle 1112 are 1:1, which can ensure both a good playback effect and a good blocking effect. At the same time, the number of baffles 1112 is preferably 4, and they are staggered at 90°, which ensures that the baffle 1112 has the effect of blocking dust and moisture while facilitating processing.

[0065] Furthermore, in order to extend the service life of the system, a layer of gauze can be completely covered on the outermost side of the sound hole 1111 to pre-block larger dust. In actual application scenarios, after the system has been used for a period of time, if there is a lot of dust attached to the gauze, it can be cleaned by flicking or shaking it, which is convenient for maintenance.

[0066] In this embodiment, by setting a baffle 1112 inside the sound hole 1111, it can not only prevent dust and water vapor, but also improve the sound level. The shape and area of ​​the baffle can be flexibly selected and designed according to the specific environmental quality, temperature and humidity of the use scene, and are not limited here.

[0067] In some embodiments, see Figure 2 and Figure 3 The electric vehicle low speed warning sound system further includes a desiccant strip 113 ; the desiccant strip 113 is fixed inside the first shell 111 and is used to absorb moisture entering the shell 11 .

[0068] For example, the first housing 111 may be arc-shaped. Figure 2 and Figure 3 Taking the orientation shown as an example, the upper and lower surfaces may be flat, and the left side surface may be an arc surface, with a hole opened on the arc surface so that the prompt sound emitted by the speaker 13 can pass through. In other embodiments, the left side surface may also be hemispherical so that the sound emitted by the speaker 13 can pass flexibly from a larger angle range to flexibly meet the prompt needs of different organisms. Among them, desiccant strips 113 may be provided on both sides of the interior of the first shell 111 to absorb moisture entering the interior of the first shell 111 from the sound hole 1111 to avoid its influence on the speaker 13 and other components in the shell 11.

[0069] In some embodiments, see Figure 1 , Figure 2 and Figure 5 The second shell 112 also has an electrical connection hole 1122 (ie, a PIN hole), which is used to connect the circuit board 14 and the vehicle computer 01 of the electric vehicle; the vehicle computer 01 is used to provide voltage and bus information (ie, CAN information) to the circuit board 14.

[0070] Exemplarily, taking the orientation relative to the electric vehicle body as an example, a PIN hole is provided on the outer bottom surface of the second shell 112 for connecting with the vehicle computer to provide voltage and vehicle CAN and other information, so as to facilitate the circuit board 14 to perform comprehensive information processing and utilization.

[0071] Based on the same inventive concept, the present invention also provides an electric vehicle low-speed warning sound method, which can be executed based on any electric vehicle low-speed warning system provided in the above-mentioned implementation manner, and can achieve corresponding beneficial effects.

[0072] The method provided by the present invention can be executed in the circuit board 14. The method is exemplarily described below in combination with input signals, signal processing and output signals.

[0073] Among them, the input signals mainly include CAN information, image information collected by the vehicle-mounted camera, and noise information collected by the sound sensor.

[0074] Specifically, the CAN information mainly corresponds to obtaining vehicle speed information, which is used as a trigger condition for the prompt sound to work. For example, according to regulatory requirements, the prompt sound system needs to work when the forward gear speed is within the range of 0-20km / h and when the reverse gear is in reverse gear.

[0075] Specifically, the image information collected by the on-board camera is the information obtained by using the camera on the electric vehicle itself to collect images. The image information is mainly used for image recognition to identify people or other objects, and to measure the distance and position of the hearing system (i.e., the ear) from the electric vehicle, so as to provide direction and sound prompts for matching distance.

[0076] Specifically, the noise information collected by the sound sensor is mainly used to characterize the noise conditions in the surrounding environment of the electric vehicle, and the noise conditions near the location of the hearing system of the organism are estimated on the circuit board through a known transfer function to determine the prompt sound parameters that are distinguished from the environmental noise.

[0077] The circuit board can receive the above input signal and perform data processing, and the specific data processing process can be performed by the controller. Exemplarily, the controller can include an information processor, an audio controller and a voltage controller. The method proposed in this embodiment is mainly performed by the information processor.

[0078] For example, Figure 7 A flowchart of a method for low-speed warning sound of an electric vehicle provided by an embodiment of the present invention. Figure 7 , the method may include the following steps:

[0079] S210: Obtain image information collected by the vehicle-mounted camera.

[0080] The circuit board is connected to the vehicle-mounted camera for communication, and can obtain image information collected by the vehicle-mounted sensor in real time or at a fixed time.

[0081] S220: Determine the position and distance between the hearing system to be prompted and the electric vehicle based on the image information.

[0082] The circuit board performs image recognition based on the image information to determine whether there is a living organism in the image, and when there is a living organism, determines the position of the hearing system of the living organism (i.e., the hearing system to be prompted) and the distance from the electric vehicle.

[0083] S230. Based on the position and distance, at least control the rotary motor to drive the speaker to rotate an angle so that the sound output direction of the speaker is toward the position of the hearing system to be prompted, and control the speaker to emit a prompt sound that matches the distance.

[0084] Among them, the circuit board sends a control signal based on the position and distance determined in the above steps to control the rotating motor to drive the speaker to rotate at an angle so that the rotation direction of the speaker is toward the hearing system to be prompted; and controls the speaker to emit a prompt sound that matches the distance.

[0085] In this embodiment, the circuit board determines the position and distance of the hearing system to be prompted from the electric vehicle based on the image information collected by the vehicle-mounted camera, and at least controls the rotating motor to drive the speaker to rotate at an angle so that the sound direction of the speaker is toward the position of the hearing system to be prompted, and controls the speaker to emit a prompt sound that matches the distance. It can combine the vehicle-mounted camera and the circuit board to realize the position and distance detection of the hearing system to be prompted, and then realize directional and accurate prompts matching the distance based on the detected distance and position.

[0086] In some embodiments, the electric vehicle low speed warning sound method may also include:

[0087] Obtain noise information collected by the sound sensor;

[0088] Determine a noise spectrum at the location of the hearing system to be prompted based on the noise information, the location of the sound sensor and the location of the hearing system to be prompted;

[0089] Based on the noise spectrum, a prompt tone parameter that is distinguished from the noise spectrum is determined.

[0090] In this embodiment, by detecting and identifying ambient noise, prompt sound parameters that are different from the noise spectrum corresponding to the ambient noise can be generated, so that the prompt sound can be clearly distinguished from the ambient noise, which facilitates the hearing system to be prompted to recognize the prompt sound and improves safety.

[0091] In some embodiments, the electric vehicle low speed warning sound method may also include:

[0092] Obtain bus information based on electrical connection hole transmission;

[0093] Based on the bus information, determine whether the current vehicle speed is within the vehicle speed threshold range matched by the prompt tone;

[0094] If the current vehicle speed is within the vehicle speed threshold range, the image information is processed.

[0095] In this embodiment, low-speed sound prompts are performed in combination with vehicle speed information to avoid high-speed prompts, reduce energy consumption, and meet low-speed prompt requirements.

[0096] In some embodiments, the electric vehicle low speed warning sound method may also include:

[0097] Based on the image information, determine whether there is a living organism in the image;

[0098] If there is a living being in the image, the position and distance of the hearing system to be prompted from the electric vehicle are determined.

[0099] In this embodiment, a sound prompt is given in combination with image recognition to determine whether a living organism exists, and the prompt is prepared only when a living organism is recognized, thereby avoiding energy consumption and reducing environmental noise pollution.

[0100] In some embodiments, the electric vehicle low speed warning sound method may also include:

[0101] The sound source is converted based on the prompt sound parameters to control the speaker to emit the corresponding prompt sound.

[0102] In this embodiment, the sound source conversion is performed according to the prompt sound parameters to meet the prompt requirements.

[0103] In some embodiments, the electric vehicle low speed warning sound method may include:

[0104] Step 1: Determine whether the vehicle speed is within the preset conditions (i.e., trigger conditions); the preset conditions include the vehicle speed being within the range of 0-20 km / h or being in reverse gear.

[0105] Step 2: If it is not within the above preset conditions, then make sure not to issue a reminder sound.

[0106] When the circuit board receives the vehicle CAN information, it determines whether the vehicle meets the triggering conditions for the prompt sound (according to national standards). When the electric vehicle speed is within the range of 0-20km / h or in the reversing state, the prompt sound system is ready to work and wait for the next triggering condition. Otherwise, it stops working.

[0107] Step 3: If it is within the above preset conditions, image recognition is performed on the image information collected by the vehicle-mounted camera and judgment is made.

[0108] Step 4: If the image does not include a living organism, determine not to issue a prompt sound reminder.

[0109] Step 5: If there are living organisms in the image, such as pedestrians, animals, etc., the location and distance of the hearing system of the living organism are further identified based on image recognition technology.

[0110] Step 6. According to the identified position and distance, control the slider to move left and right, and control the rotary motor to rotate the angle to point the speaker to the target position and prepare to issue a prompt sound reminder.

[0111] Among them, real-time image information of the vehicle's surrounding environment is collected through systems such as on-board cameras, and surrounding objects such as pedestrians, animals, trash cans, trees, etc. are identified through image recognition technology. If a biological body that needs to issue a warning sound is identified, such as a pedestrian, cyclist or animal, the circuit board will calculate the position near its hearing system and the distance relative to the vehicle. Through the controller in the circuit board, a signal is sent to the sliding motor to adjust the left and right position of the speaker on the fixed bracket, and a signal is sent to the rotating motor to adjust the speaker to point to the identified biological body. If a trash can, tree or other non-biological body is identified, the position of the warning sound device remains unchanged and it also stops working, so as to save energy and reduce pollution to the surrounding environment.

[0112] Step 7. Analyze the noise conditions at the target location (i.e., the location of the hearing system) based on the noise information collected by the sound sensor to generate a noise spectrum, and determine the prompt sound parameters. The prompt sound parameters must be within the noise range required by regulations (e.g., GBT37153-2018 "Low-speed Prompt Sound for Electric Vehicles" and GB1495-2002 "External Noise Limits and Measurement Methods for Accelerating Vehicles").

[0113] For example, the generation of prompt sound parameters may include: 1) increasing the overall sound pressure level, 2) increasing the sound frequency, 3) increasing both the sound pressure level and the sound frequency. The adjustment method may be selected according to actual conditions to improve the recognizability of the prompt sound and complete the prompt function.

[0114] Among them, in order to improve the accuracy of the prompt, it is necessary to collect the noise environment near the hearing system to be prompted, but the sound sensor is set on both sides of the shell, and there is a certain distance between it and the biological body. It is impossible to directly estimate the vicinity of the pedestrian's ear. Circuit board simulation or actual testing is required to measure the sound transfer function of each position around the vehicle relative to the prompt sound device, and then calculate the noise spectrum near the hearing system through the sound sensor. Since GBT 37153-2018 "Low-speed Prompt Sound of Electric Vehicles" has requirements for sound pressure level and frequency, such as when the forward speed is 10km / h, the total sound pressure level of the prompt sound shall not be less than 52dB (A), and when the forward speed is 20km / h, the total sound pressure level of the prompt sound shall not be less than 58dB (A); and GB1495-2002 "External Noise Limits and Measurement Methods for Accelerating Vehicles" requires that the external passing noise of the vehicle is less than 75dB (A), so the sound pressure level and frequency of the prompt sound need to meet two regulations. If the environmental noise is too loud, it is necessary to improve the recognizability of the prompt sound. This embodiment provides three adjustment methods: 1. increasing the overall sound pressure level, 2. increasing the sound frequency, and 3. increasing both the sound pressure level and the sound frequency. Adjustments can be made in real time according to actual conditions to improve the recognizability of the prompt tone.

[0115] Furthermore, the audio controller in the circuit board is used to convert the prompt sound source.

[0116] Finally, based on the above trigger conditions, the controller transmits the signal to the speaker, and the speaker works to emit the required prompt sound to alert the surrounding pedestrians or other organisms.

[0117] At the same time, the selection of prompt sound effects should not only take into account the sound pressure level, but also the sound quality of the sound effects, so that people will not feel bored after hearing them, causing noise pollution.

[0118] Furthermore, the voltage controller in the circuit board is used to control the system voltage to 12V, so as to prevent the vehicle voltage from being too high or too low, which would affect the normal use of the system.

[0119] Among them, the output signal of the circuit board is used to control the action of the rotating motor (or also including the slider motor) so that the position and angle of the speaker point to the hearing system to be prompted; on the other hand, it controls the speaker to sound a prompt sound to alert the organism (such as a pedestrian).

[0120] Based on the same inventive concept, the present invention also provides an electric vehicle low-speed warning sound device, which can be arranged in the circuit board of any electric vehicle low-speed warning sound system provided in the above embodiments, and is used to execute the steps of any of the above electric vehicle low-speed warning sound methods to achieve corresponding beneficial effects.

[0121] It should be noted that the terms used in the present invention are only for describing specific embodiments, rather than limiting the scope of the present application. As shown in the present specification, unless the context clearly indicates an exception, the words "one", "a", "a kind of" and / or "the" do not specifically refer to the singular, but may also include the plural. The terms "include", "comprise" or any other variant thereof are intended to cover non-exclusive inclusion, so that the process, method or device including a series of elements includes not only those elements, but also includes other elements not explicitly listed, or also includes elements inherent to such process, method or device. In the absence of further restrictions, the elements defined by the sentence "include one..." do not exclude the presence of other identical elements in the process, method or device including the elements.

[0122] It should also be noted that the terms "center", "up", "down", "left", "right", "vertical", "horizontal", "inside", "outside", etc., indicating the orientation or positional relationship, are based on the orientation or positional relationship shown in the drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present invention. Unless otherwise clearly specified and limited, the terms "installed", "connected", "connected", etc. should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be an indirect connection through an intermediate medium, or it can be a connection between the two elements. For those of ordinary skill in the art, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0123] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or replace some or all of the technical features therein by equivalents. However, these modifications or replacements do not deviate the essence of the corresponding technical solutions from the technical solutions of the embodiments of the present invention.

Claims

1. An electric vehicle low speed warning sound system, characterized in that: include: Housing, rotating motor, speaker, circuit board, sound sensor, moving bracket, slider and fixed bracket; The speaker is connected to the housing through the rotating motor, and the rotating motor is used to drive the speaker to rotate; the circuit board is fixed in the housing, the rotating motor and the speaker are both connected to the circuit board for communication, and the circuit board is also connected to the vehicle camera; The circuit board is used to determine the position and distance of the hearing system to be prompted from the electric vehicle based on the image information collected by the vehicle-mounted camera, and at least control the rotary motor to drive the speaker to rotate an angle so that the sound output direction of the speaker is toward the position of the hearing system to be prompted, and control the speaker to emit a prompt sound matching the distance; The sound sensor is fixed in the placement hole of the shell through a bracket, and the end surface of the sound sensor is on the same plane as the end surface of the placement hole; The sound sensor is connected to the circuit board; The sound sensor is used to measure the environmental noise around the electric vehicle, obtain noise information, and transmit it to the circuit board; The circuit board is used to determine the noise spectrum at the position of the hearing system to be prompted based on the noise information, the position of the sound sensor and the position of the hearing system to be prompted, and determine the prompt sound parameters that are different from the noise spectrum; The housing is fixed to the slider via the movable bracket, the slider is slidably connected to the fixed bracket, and the fixed bracket is used to fix the system to the body of the electric vehicle; The slider is also connected to the circuit board; The circuit board is also used to control the slider to drive the housing to slide based on the position and distance of the hearing system to be prompted from the electric vehicle, so as to drive the speaker to slide synchronously; The housing comprises a first housing and a second housing sealed with the first housing; A sealing strip is provided on the edge of the first shell facing the second shell, and a groove is provided on the edge of the second shell facing the first shell; The first shell and the second shell are sealed by the groove, and the sealing strip is filled in the gap between the first shell and the second shell; The first shell is in a hemispherical or arc shape and is provided with a sound hole; The sound hole is used to allow the prompt sound emitted by the speaker to pass through; The first housing further comprises a baffle, which is arranged at the location of the sound hole and is used to prevent dust and moisture from entering the housing; The baffle has a trumpet-shaped through hole, and the diameter of the trumpet-shaped through hole toward the outside of the shell is larger than the diameter toward the inside of the shell; The baffle is in a semicircular shape; The number of the baffles is equal to or greater than two, and the baffles are staggeredly distributed in the sound hole along the axial direction of the sound hole.

2. The electric vehicle low speed warning sound system according to claim 1, characterized in that: Also included are desiccant strips; The desiccant strip is fixed inside the first shell and is used to absorb moisture entering the shell.

3. The electric vehicle low speed warning sound system according to claim 1, characterized in that: The second housing further has an electrical connection hole, and the electrical connection hole is used to connect the circuit board and the vehicle computer of the electric vehicle; The vehicle computer is used to provide voltage and bus information to the circuit board.

4. A method for low-speed warning sound of electric vehicle, characterized in that: Based on the electric vehicle low speed warning system according to any one of claims 1 to 3, the method comprises: Obtain image information collected by the vehicle-mounted camera; Based on the image information, determining the position and distance of the hearing system to be prompted from the electric vehicle; Based on the position and the distance, at least the rotary motor is controlled to drive the speaker to rotate at an angle so that the sound output direction of the speaker is toward the position of the hearing system to be prompted, and the speaker is controlled to emit a prompt sound matching the distance; Obtain noise information collected by the sound sensor; Determine a noise spectrum at the position of the hearing system to be prompted based on the noise information, the position of the sound sensor and the position of the hearing system to be prompted; Based on the noise spectrum, a prompt tone parameter that is different from the noise spectrum is determined.

5. The electric vehicle low speed warning sound method according to claim 4, characterized in that: Also includes: Obtain bus information based on electrical connection hole transmission; Based on the bus information, determining whether the current vehicle speed is within a vehicle speed threshold range matched by the prompt tone; If the current vehicle speed is within the vehicle speed threshold range, processing the image information; And / or, the method further comprises: Based on the image information, determining whether there is a living thing in the image; If there is a living being in the image, the position and distance of the hearing system to be prompted from the electric vehicle are determined.

6. The electric vehicle low speed warning sound method according to claim 4 or 5, characterized in that: Also includes: The sound source is converted based on the prompt sound parameter to control the speaker to emit a corresponding prompt sound.

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