System and method for synthesizing a motor vehicle sound in a motor vehicle

Abstract

A system for synthesizing and outputting a motor vehicle sound in a motor vehicle (10), comprising: - at least one detection device (12a to 12f) of an environmental condition in an external environment of the motor vehicle (10); - a device for synthesizing (14) the motor vehicle noise as a function of at least one operating parameter of the motor vehicle (10) and the at least one detected environmental condition; and - a noise generating device (16) for generating sound waves as a function of the synthesized motor vehicle noise, wherein the noise generating device (16) comprises at least one loudspeaker arranged in the interior of the motor vehicle (10), characterized in that the system further comprises an input device (20) for a user and a selection device (22), wherein the selection device (22) is designed to provide a basic sound file selected by the user to the device for synthesizing (14) the motor vehicle noise for modification as a function of the at least one detected environmental condition, wherein the basic sound file represents an interior noise of a motor vehicle as the starting material for synthesizing the motor vehicle noise.

Description

[0001] The present invention relates to a system for synthesizing a motor vehicle sound in a motor vehicle. This system comprises at least one detection device for detecting an ambient condition in an external environment of the motor vehicle, a device for synthesizing the motor vehicle sound as a function of at least one operating parameter of the motor vehicle and the at least one detected ambient condition, and a noise generation device for generating sound waves as a function of the synthesized motor vehicle sound. It also relates to a method for synthesizing a motor vehicle sound in a motor vehicle, in which at least one ambient condition in an external environment of the motor vehicle is first detected.Subsequently, the motor vehicle noise is synthesized as a function of at least one operating parameter of the motor vehicle and the at least one detected environmental condition, and finally, sound waves are generated as a function of the synthesized motor vehicle noise. The invention further relates to a motor vehicle with a system for synthesizing a motor vehicle noise.

[0002] A generic system and method are known from DE 10 2012 213 198 A1. This document deals with controlling a virtual engine sound of a hybrid vehicle or an electric vehicle, which comprises a detection device for detecting when the vehicle is inside, e.g., inside a tunnel or inside a garage. It further comprises a virtual engine sound generation section for generating the virtual engine sound of the vehicle and a control section for receiving data detected by the detection device. The virtual engine sound is controlled based on whether the vehicle is inside. It comprises a section for generating a corresponding virtual engine sound.In this context, when the vehicle is in an internal environment, such as surrounded by the walls of a building or the walls of a tunnel, the detection sensor detects that the environmental condition has changed due to the walls of the building or the walls of the tunnel. When the vehicle is inside, the control section is configured to control the volume of the sound output by the system, a sound pressure, and a frequency of the virtual engine sound. Specifically, the volume and sound pressure of the virtual engine sound are reduced. The virtual engine sound is output to the outside of the vehicle through a speaker installed in an engine compartment. This ensures that the volume of the virtual engine sound is not excessively loud and disturbing in the internal environment.

[0003] US 2014 / 0056438 A1 discloses a vehicle sound system that can be adapted to an external condition in the vehicle's exterior environment. The sound waves are audible outside the vehicle. Acoustic properties such as frequency, amplitude, phase, modulation, and time delay can be adjusted or selected. The generated sound can be audible both inside and outside the vehicle.

[0004] US 2011 / 0044470 A1 discloses an artificial engine noise generator. It takes the vehicle's driving environment into account, alerting pedestrians to the presence of an electric vehicle.

[0005] DE 10 2013 204 798 A1 relates to an environmental information notification device for a vehicle.It includes an interior sound acquisition device that acquires a sound in a passenger compartment of the vehicle, referred to as interior sound, a surrounding information presentation sound generator that generates an environment information presentation sound that satisfies a first condition and a second condition with respect to the interior sound, and an environment information presentation sound output device that outputs the environment information presentation sound, wherein the first condition is that a sound pressure level of the environment information presentation sound is higher in a predetermined frequency band and equal to or lower than that of the interior sound in the other frequency band, and the second condition is that the environment information presentation sound is provided by stereophony in which a sound visual localization direction is approximately directed to a virtual sound source.

[0006] DE 10 2012 218 482 A1 relates to a method for operating a driver assistance system of a vehicle, in which the vehicle has a plurality of microphones configured to detect ambient noise impinging on the vehicle from outside. The vehicle has a plurality of loudspeakers arranged in the vehicle. The ambient noise is reproduced in a directionally accurate manner by the loudspeakers, with at least one loudspeaker assigned to each microphone.

[0007] DE 10 2017 220 394 A1 relates to a method for operating a driver assistance system for a motor vehicle, which is assigned a communication interface, sensors, and an output unit, which are signal-coupled to a control unit of the motor vehicle. Data comprising traffic-relevant information about the vehicle's surroundings is received. The vehicle's surroundings are then determined based on the received data. Furthermore, an object in the vehicle's surroundings is determined based on the received data, and, if an object is determined, a direction is assigned for the determined object relative to the motor vehicle. Measurement signals comprising information about a driving movement of the motor vehicle are received from the sensor system of the motor vehicle. A trajectory of the motor vehicle is then determined based on the received measurement signals from the sensor system.Subsequently, the current driving situation for the vehicle is determined based on the detected vehicle environment and the determined trajectory. Finally, acoustic information is output via the output unit in a directionally accurate manner, depending on the object and the direction assigned to the object and the determined driving situation.

[0008] DE 10 2012 011 171 A1 relates to a method for displaying a recommended cornering speed in a vehicle. A driving profile characterized by a number of parameters is specified. A recommended cornering speed is then determined for a curve to be negotiated based on the geometry of the curve and the specified driving profile. Finally, a recommended cornering speed is output to the driver. The output can also be acoustic. For example, a warning tone could alert the driver that the recommended cornering speed has been exceeded or is about to be exceeded. An increasing volume and / or increasing frequency of a repeating warning tone could indicate that the recommended cornering speed is approaching.The friction coefficient of the road surface and / or the current load of the vehicle and / or weather data and / or traffic data can be used to determine the recommended cornering speed.

[0009] DE 10 2017 204 895 A1 relates to a method for entertaining a user of a vehicle, in which information about a detour around the vehicle is acquired by means of at least one sensor of the vehicle and the information is output via at least one output medium of the vehicle. When outputting the information acquired by the at least one sensor, at least part of the information generated by the vehicle itself is suppressed. For example, the following information can be acquired and output in the interior of a respective vehicle: odors, temperature, solar radiation, humidity, wind speed, wind direction, and / or vibrations of a current surface of the vehicle. Possible sensors include: interior microphone, exterior microphone, interior camera, exterior camera, rain sensor, interior temperature sensor, exterior temperature sensor, interior fragrance sensor, and exterior fragrance sensor.

[0010] DE 10 2015 114 667 A1 relates to a device for emitting acoustic signals in at least part of a passenger compartment of a motor vehicle. The acoustic signal can comprise a main signal and various secondary acoustic signals. Among the secondary acoustic signals, a sound from at least one natural event, in particular a sound from a body of water, precipitation, an earthquake, a volcanic eruption, or wind, can be considered.

[0011] The object of the present invention is to further develop a system and a method mentioned above in such a way that traffic safety can be further increased.

[0012] This object is achieved by a system having the features of patent claim 1, a method having the features of patent claim 8 and by a motor vehicle having the features of patent claim 9.

[0013] The present invention is based on the realization that the better a motor vehicle driver is aware of the environmental conditions in the vehicle's external environment, the greater the road safety that can be achieved. While the prior art seeks to achieve high road safety by informing pedestrians of the presence of an electric vehicle while avoiding unnecessary noise, the present invention specifically aims to inform the driver of a motor vehicle of environmental conditions. The driver's attention should be distracted from the traffic as little as possible.This is achieved by not displaying the ambient conditions, such as precipitation, driving through a tunnel, or cornering, on a special display instrument, but rather taking them into account when synthesizing the vehicle noise. The noise generation device comprises at least one loudspeaker located in the interior of the vehicle. This means that the driver is almost incidentally informed of road safety-relevant aspects in the vehicle's external environment. Because the driver receives subtle, i.e. more or less unconscious, information about the vehicle's surroundings, their attention is almost never distracted from the traffic situation. Furthermore, despite the reliable provision of information to the driver, the vehicle's external environment is not disturbed by noise.

[0014] A preferred embodiment is characterized in that the at least one detection device is designed to detect a reverberant environment of the motor vehicle, wherein the device for synthesizing the motor vehicle noise is designed to synthesize the motor vehicle noise with reverberation. The detection device can be embodied as a navigation system, which typically has a GPS system to detect a position of the motor vehicle. Together with electronically provided map material, it can be used to determine whether the motor vehicle is in a tunnel, an underground parking garage, a passageway, or the like.By knowing that the vehicle is in a tunnel, especially when driving at night, the driver can drive with particular caution, for example, by reducing vehicle speed, avoiding overtaking, and preparing for crosswinds when exiting the tunnel. In this context, the detection device can also be designed as an external microphone to detect reverberant noise around the vehicle.

[0015] In a further preferred embodiment, the detection device is designed to detect cornering of the motor vehicle, wherein the device for synthesizing the motor vehicle noise is designed to synthesize the motor vehicle noise with a noise of squealing tires depending on a predeterminable relationship between the curve radius and the vehicle speed. If a driver of a motor vehicle hears the tires squealing while cornering, they know that the motor vehicle is in a limit range of static friction or has already exceeded it.By selecting the threshold value of the relationship between curve radius and vehicle speed at which the curve noise is generated, which is a predeterminable percentage lower than the relationship at which the motor vehicle actually loses static friction, safety reserves are created that can prevent the vehicle from skidding. The point at which the tires lose static friction can be estimated by evaluating the vehicle's steering and tracking behavior. If a driver hears squealing tires, they assume they are already at the limit and usually ease off the accelerator. In reality, however, the motor vehicle in the present invention is not yet at the limit. The predeterminable threshold value of the relationship between curve radius and vehicle speed can be adjustable so that, for example, a lower value can be selected for novice drivers than for experienced drivers.

[0016] The device for synthesizing the vehicle noise can be designed to vary the volume and / or frequency of the tire squealing noise depending on the relationship between the curve radius and the vehicle speed. This presents the driver with a largely realistic effect, while the vehicle is not yet at the limit, but rather on the safe side. A gyro sensor can be used to determine the relationship between the curve radius and the vehicle speed. Alternatively, the vehicle speed can be determined using a vehicle speedometer, with the curve radius being determined using the navigation system and corresponding electronic map material.

[0017] The detection device can also be designed as a precipitation sensor, with the device for synthesizing the vehicle noise being configured to synthesize the vehicle noise depending on the detected precipitation density. This allows the driver, for example, to adjust their speed to the intensity of the rain.

[0018] In a further preferred embodiment, the detection device is designed to detect at least one parameter of a road surface, wherein the device for synthesizing the motor vehicle noise is designed to synthesize the motor vehicle noise as a function of the at least one parameter of the road surface. The at least one parameter of the road surface can, for example, relate to the road surface, for example tar, gravel, or concrete, but can also relate to whether the road is wet, covered in snow, contaminated, or whether there are puddles on the road. For this purpose, an external camera of the motor vehicle, which is coupled to an image processing device, is preferably used as the detection device. In this way, the driver can then also adjust the vehicle speed to the road conditions communicated to him.

[0019] The detection device can also be designed as a temperature sensor, with the device for synthesizing the motor vehicle sound being configured to synthesize the motor vehicle sound depending on a detected temperature. Since air density varies at different temperatures, different sound speeds also result depending on the temperature. These are usually perceived subconsciously. According to the invention, the motor vehicle sound is synthesized depending on a detected temperature, allowing the driver to adjust their speed accordingly. For example, the braking distance is longer at low temperatures than at high temperatures.

[0020] Further advantageous embodiments emerge from the subclaims.

[0021] The preferred embodiments presented in connection with the system according to the invention and their advantages apply accordingly, as far as applicable, to the method according to the invention for synthesizing a motor vehicle sound in a motor vehicle and to the motor vehicle according to the invention with a system according to the invention for synthesizing a motor vehicle sound.

[0022] In the following, embodiments of the present invention will be described in more detail with reference to the accompanying drawings. These show: Fig. 1 is a schematic representation of an embodiment of a system according to the invention for synthesizing a motor vehicle sound in a motor vehicle; and Fig. 2 shows a signal flow graph for an embodiment of a method according to the invention for synthesizing a motor vehicle noise in a motor vehicle.

[0023] In the following, the same reference symbols are used for identical and similarly acting figures.

[0024] The exemplary embodiments explained below are preferred embodiments of the invention. In the exemplary embodiments, the described components of the embodiments each represent individual features of the invention that can be considered independently of one another, each of which also further develops the invention independently of one another.

[0025] Therefore, the disclosure is intended to encompass combinations of the features of the embodiments other than those shown. Furthermore, the described embodiments can also be supplemented by further features of the invention already described.

[0026] Fig. 1 shows a schematic representation of an embodiment of a system according to the invention for synthesizing a motor vehicle sound in a motor vehicle 10. This system comprises a plurality of detection devices 12a to 12f for detecting an ambient condition in an external environment of the motor vehicle 10. Detection device 12a is designed as an external microphone to detect a reverberant environment of the motor vehicle. Detection device 12b is designed to detect cornering of the motor vehicle. Detection device 12c is designed as a precipitation sensor, and detection device 12d is designed to detect at least one parameter of a road surface.The detection device 12e is designed as a temperature sensor to detect an outside temperature of the motor vehicle, while the detection device 12f is formed by a navigation system which, in conjunction with corresponding electronic map material, is able to determine the position of a motor vehicle, for example whether the motor vehicle is inside or outside a tunnel, in an underpass, an underground car park or the like.

[0027] The detection devices 12a to 12f are coupled to a device 14 for synthesizing the motor vehicle noise as a function of at least one operating parameter of the motor vehicle 10 and the at least one detected environmental condition. A device 18 serves to provide a signal to the device 14 for synthesizing the motor vehicle noise, which signal is coupled to at least one operating parameter of the motor vehicle. The at least one operating parameter of the motor vehicle can be, for example, its speed, its acceleration, an accelerator pedal position, a brake pedal position, a power drawn, for example from a vehicle battery, a speed of an electric motor, or the like.

[0028] In the case of the detection device 12a, the device 14 for synthesizing the vehicle sound is designed to synthesize the vehicle sound with reverberation. Reverberation refers to sound with gradually fading, weakening, audible vibrations.

[0029] In the case of the detection device 12b, the device 14 for synthesizing the motor vehicle noise is designed to synthesize the motor vehicle noise with a squealing tire noise depending on a predeterminable relationship between the curve radius and the vehicle speed. The device 14 for synthesizing the motor vehicle noise can be designed to vary the volume and / or frequency of the squealing tire noise depending on the relationship between the curve radius and the vehicle speed.

[0030] In the case of the detection device 12c, the device 14 for synthesizing the motor vehicle noise is designed to synthesize the motor vehicle noise as a function of a detected precipitation density.

[0031] In the case of the detection device 12e, the device 14 for synthesizing the motor vehicle noise is designed to synthesize the motor vehicle noise as a function of the at least one parameter of the road surface.

[0032] In the case of the detection device 12f, the device 14 for synthesizing the motor vehicle noise is designed to synthesize the motor vehicle noise as a function of a detected temperature.

[0033] Of course, the device 14 for synthesizing the motor vehicle noise can simultaneously take into account the different detection signals provided by the detection devices 12a to 12f relating to respective ambient conditions when synthesizing the motor vehicle noise.

[0034] The system according to the invention further comprises a noise generation device 16 for generating sound waves as a function of the synthesized motor vehicle noise. This device is therefore coupled to the device 14 for synthesizing the motor vehicle noise.

[0035] According to the invention, the noise generating device 16 comprises at least one loudspeaker arranged in the interior of the motor vehicle 10 and radiating sound waves into the interior, i.e., the passenger compartment, of the motor vehicle 10. In this way, the synthesized motor vehicle noise can be provided, in particular, to a driver of the motor vehicle 10.

[0036] The system according to the invention for synthesizing a motor vehicle sound in the motor vehicle 10 further comprises an input device 20 for a user and a selection device 22, which is designed to provide a base sound file selected by the user to the device for synthesizing the motor vehicle sound. The base sound file is then modified by the device 14 for synthesizing the motor vehicle sound depending on the detected ambient conditions. For example, the base sound file can relate to an interior sound of a Porsche 911 or a Bugatti Veyron, which is provided to the device 14 for synthesizing the motor vehicle sound as starting material for synthesizing the motor vehicle sound. The device 22 can offer a plurality of base sound files of the most diverse vehicle types for selection, but also at least one vehicle-neutral base sound file.This can give the vehicle occupants the acoustic impression that they are sitting in their dream car without disturbing the surroundings of the motor vehicle 10 with noise.

[0037] Fig. 2 shows a signal flow graph for an embodiment of a method according to the invention for synthesizing a motor vehicle sound in a motor vehicle 10. First, in step 100, at least one environmental condition in an external environment of the motor vehicle is detected. Subsequently, in step 120, the motor vehicle sound is synthesized as a function of at least one operating parameter of the motor vehicle and the at least one detected environmental condition. Finally, in step 140, sound waves are generated as a function of the synthesized motor vehicle sound. The sound waves generated as a function of the synthesized motor vehicle sound are output via at least one loudspeaker arranged in the interior of the motor vehicle.

[0038] While exterior noise emissions must comply with noise emission regulations, noise emissions inside a motor vehicle are currently not yet limited. Generating a relevant noise inside the vehicle using exterior loudspeakers, as in the prior art, would exceed the relevant legal limits. According to the invention, a desired interior noise of the motor vehicle can be generated without conflicting with legal regulations regarding noise emissions.

Claims

[1] A system for synthesizing and outputting a motor vehicle sound in a motor vehicle (10), comprising: - at least one detection device (12a to 12f) of an environmental condition in an external environment of the motor vehicle (10); - a device for synthesizing (14) the motor vehicle noise as a function of at least one operating parameter of the motor vehicle (10) and the at least one detected environmental condition; and - a noise generating device (16) for generating sound waves as a function of the synthesized motor vehicle noise, wherein the noise generating device (16) comprises at least one loudspeaker arranged in the interior of the motor vehicle (10), characterized bythat the system further comprises an input device (20) for a user and a selection device (22), wherein the selection device (22) is designed to provide a basic sound file selected by the user to the device for synthesizing (14) the motor vehicle noise for modification depending on the at least one detected environmental condition, wherein the basic sound file represents an interior noise of a motor vehicle as starting material for synthesizing the motor vehicle noise. [2] System according to claim 1, characterized by that the at least one detection device (12a; 12f) is designed to detect a reverberating environment of the motor vehicle (10), wherein the device for synthesizing (14) the motor vehicle noise is designed to synthesize the motor vehicle noise with reverberation. [3] System according to one of the preceding claims, characterized bythat the at least one detection device (12b) is designed to detect cornering of the motor vehicle (10), wherein the device for synthesizing (14) the motor vehicle noise is designed to synthesize the motor vehicle noise with a noise of squealing tires as a function of a predeterminable relationship between curve radius and vehicle speed. [4] System according to claim 3, characterized by that the device for synthesizing (14) the motor vehicle noise is designed to vary the volume and / or frequency of the noise of squealing tires depending on the relationship between curve radius and vehicle speed. [5] System according to one of the preceding claims, characterized bythat the at least one detection device (12c) is designed as a precipitation sensor, wherein the device for synthesizing (14) the motor vehicle noise is designed to synthesize the motor vehicle noise as a function of a detected precipitation density. [6] System according to one of the preceding claims, characterized by that the at least one detection device (12d) is designed to detect at least one parameter of a road surface, wherein the device for synthesizing (14) the motor vehicle noise is designed to synthesize the motor vehicle noise as a function of the at least one parameter of the road surface. [7] System according to one of the preceding claims, characterized bythat the at least one detection device (12e) is designed as a temperature sensor, wherein the device for synthesizing (14) the motor vehicle noise is designed to synthesize the motor vehicle noise as a function of a detected temperature. [8] A method for synthesizing and outputting a motor vehicle sound in a motor vehicle (10) comprising the following steps: - detecting at least one environmental condition in an external environment of the motor vehicle (10) (step 100); - selecting a base sound file by user input, the base sound file being an interior sound of a motor vehicle as the source material for synthesis; - Synthesizing the motor vehicle sound as a function of at least one operating parameter of the motor vehicle (10) and the at least one detected environmental condition (step 120) by modifying the base sound file as a function of the at least one detected environmental condition; and - generating sound waves as a function of the synthesized motor vehicle noise (step 140), wherein the sound waves generated as a function of the synthesized motor vehicle noise are output via at least one loudspeaker arranged in the interior of the motor vehicle (10). [9] A motor vehicle (10) comprising a system for synthesizing and outputting a motor vehicle sound according to any one of claims 1 to 7.

Images