CN112585992A

CN112585992A - Sensor device for detecting acoustic signals in the surroundings of a vehicle

Info

Publication number: CN112585992A
Application number: CN201980057280.0A
Authority: CN
Inventors: M·舒曼; K·克里
Original assignee: Robert Bosch GmbH
Current assignee: Robert Bosch GmbH
Priority date: 2018-09-03
Filing date: 2019-08-26
Publication date: 2021-03-30
Anticipated expiration: 2039-08-26
Also published as: CN112585992B; WO2020048807A1; DE102018214898A1

Abstract

A sensor device (100) is described for detecting an acoustic signal source (310) in the environment of a vehicle (200), comprising: - at least one acoustic sensor (110, 120, 130, 140) with a sound receiver (111, 121, 131, 141) for detecting an acoustic signal of the acoustic signal source (310) in the environment of the vehicle (200), wherein the sound receiver (111, 121, 131, 141) is arranged in the vehicle ( 200), the cavity being delimited on at least one side by an outer wall (210) of the vehicle (200); and comprising a control device (150) for evaluating the detected acoustic signal (311), wherein the control device (150) is configured to: identify the at least one acoustic signal source (310) by means of the acquired acoustic signal (311) and determine the position of the signal source relative to the vehicle (200).

Description

Sensor device for detecting acoustic signals in the surroundings of a vehicle

The invention relates to a sensor device for detecting acoustic signals in the surroundings of a vehicle; and a control device for a corresponding sensor device.

Modern vehicles use different environmental sensors for monitoring the vehicle environment and for detecting possible hazards. A corresponding sensor system, which is currently also used as an assistance system to support the driver, forms the basis for future autonomous vehicles. For detecting the surroundings of the vehicle, various measuring methods are used, such as, for example, cameras, Lidar (laser radar), radar or ultrasonic sensors. According to the prior art, acoustic signals in the vehicle environment in the audible range are not detected under standard conditions. Valuable additional information is thereby lost, which may contribute significantly to safety in road traffic. In vehicles that are currently still controlled by the driver, the corresponding acoustic additional information can be perceived with the hearing of the driver (the H-bar), for example. The ambient sound may however be covered by noisy noise inside the vehicle, such as e.g. a radio or a shout of a child. The driver may also be distracted by corresponding room noise or other aspects. In automated vehicles, however, the ambient sound perceived by the driver is not integrated into the determination of the vehicle environment by the control system of the vehicle. In this case, the information contained in the audible range is not taken into account. In addition to perceiving acoustic signals in road traffic, human vehicle drivers are also typically able to determine the direction of the acoustic signals using both of their ears. However, due to the closed design of the passenger compartment, the direction determination is often relatively difficult for the vehicle driver and is therefore usually carried out very late. The direction detection is therefore usually possible only with limited success for acoustic signals from the vehicle environment.

It has proven difficult to: microphones for applications outside of vehicles have been developed, which are suitable for use in automobiles, since microphones mounted at the outside of vehicles are subject to wind, moisture, dirt and further threats. The arrangement of the respective microphones within the passenger compartment has the following disadvantages in contrast: there is noisy internal noise (e.g. caused by broadcasting or ventilation) as interference.

The task of the invention is therefore: a possible solution is provided for detecting acoustic signals in the surroundings of a vehicle. The object is achieved by a sensor device according to claim 1. The object is also achieved by a control device according to claim 11. Further advantageous embodiments of the invention are specified in the dependent claims.

According to a first aspect of the invention, a sensor device for detecting an acoustic signal in the surroundings of a vehicle is provided. The sensor device comprises at least one acoustic sensor with a sound receiver for detecting an acoustic signal of an acoustic signal source in the surroundings of the vehicle, wherein the sound receiver is arranged in a cavity of the vehicle, which is delimited at least on one side by an outer wall of the vehicle. The sensor device further comprises a control device for evaluating the detected acoustic signals. The control device is designed to: the at least one acoustic signal source is identified by means of the acoustic signals and the direction and/or position of the signal source relative to the vehicle is determined. The detection of acoustic signals in the vehicle environment provides valuable additional information. In this case, the acoustic signal itself can be used to identify the source of this acoustic signal or to determine the relative position of the source with respect to the vehicle itself, which is outside the field of view or range of conventional vehicle sensors. The acoustic sensor system is therefore very advantageous for increasing the safety in road traffic, not only in vehicles with a driver, but also in fully automatic vehicles.

In a further embodiment, provision is made for: the cavity is designed as a resonator for amplifying at least one predetermined frequency. By means of this special configuration of the cavity, a particularly high sensitivity of the acoustic sensor can be achieved for the acoustic signal of a specific acoustic signal source.

In a further embodiment, provision is made for: the outer wall of the vehicle which delimits the cavity is designed as a resonator for at least one predetermined frequency. By means of this measure, the sensitivity of the acoustic sensor can also be significantly increased for the acoustic signal of the determined acoustic signal source.

In a further embodiment, provision is made for: the sensor device is optimized for detecting the following frequencies: this frequency is typical for the acoustic signal of the at least one defined acoustic signal source. In this case, special signals, for example, tunnel entries, shouts of children, intersections or traffic accidents, emergency vehicles or emergency vehicles, are provided as acoustic signal sources. The targeted optimization of the sensor device with respect to the frequency of the determined acoustic signals makes it possible to better detect the respective acoustic signal source.

In a further embodiment, provision is made for: the cavity of the at least one acoustic sensor is designed cylindrically, and the sound receiver is designed in the form of a microphone which is arranged on a side wall of the cylindrical cavity opposite the outer wall of the vehicle. This particular arrangement makes it possible for the microphone to be coupled particularly well to the acoustic environment of the vehicle, while at the same time being decoupled well from the interior of the vehicle.

In a further starting point, provision is made for: the at least one acoustic sensor comprises a functional layer in the form of a lambda/4 layer for matching the acoustic impedance, which functional layer is arranged on the inside of an outer wall of the vehicle, which outer wall delimits the cavity. This increases the amplification of the cavity resonator with respect to a certain frequency.

In a further embodiment, provision is made for: the sound receiver of the at least one acoustic sensor is designed in the form of the following solid-state sound transmitter: the solid acoustic receiver is arranged on the inside of an outer wall of the vehicle, which outer wall defines the cavity. This arrangement makes it possible to couple particularly well with the acoustic environment of the vehicle, while at the same time decoupling well from the vehicle interior. In a further embodiment, provision is made for: the sensor device comprises a system of a plurality of acoustic sensors, which are arranged at a distance from one another on one or more sides of the vehicle. The use of a plurality of sensors allows the sensitivity to be increased. Furthermore, the special arrangement of the sensors on several sides of the vehicle makes it possible to improve the direction detection for the signal source.

In a further embodiment, provision is made for: the acoustic sensors are arranged in pairs on respectively opposite sides of the vehicle. By means of this particular arrangement of the acoustic sensors, the direction determination for the acoustic signal source is significantly improved.

In a further embodiment, provision is made for: the at least one acoustic sensor is arranged in a door of the vehicle or in a roof structure of the vehicle. The arrangement of the acoustic sensor within the vehicle door makes it possible to use the already existing cavity within the door. In contrast, the arrangement of the acoustic sensor in the roof structure allows the sensitivity to be increased, since the possible blocking of the acoustic signal is reduced by the relatively high installation position. In addition, in particular in fully automatic vehicles, it is possible to use the already existing roof structure as a mounting point.

According to a further aspect, a control device for a sensor system is provided, which is used to detect acoustic signals in the surroundings of a vehicle. The control device is designed to evaluate the following sensor signals: due to the received acoustic signal, the sensor signal is emitted by at least one acoustic sensor arranged on the inside of the outer wall of the vehicle in order to identify an acoustic signal source which emits the acoustic signal and to determine the direction and/or position of the signal source relative to the vehicle.

The invention is further described below with the aid of the figures.

Here, the drawings show:

fig. 1 shows a driving situation in which a vehicle equipped with an acoustic sensor device detects a vehicle driving behind it;

FIG. 2 shows a block diagram of a sensor device of the vehicle from FIG. 1;

FIG. 3 shows a schematic illustration of the vehicle from FIG. 1;

FIG. 4 shows a transmission system placed in the roof structure;

fig. 5 shows a schematic illustration of the roof construction from fig. 4;

fig. 6 shows a simplified embodiment of the roof structure with two acoustic sensors;

fig. 7 shows an embodiment of the acoustic sensor 110 with a microphone as a sound receiver;

fig. 8 shows an alternative embodiment of the acoustic sensor with a sound receiver in the form of a solid-state sound transmitter;

figure 9 schematically shows a frequency response curve of a cavity resonator (hohlrauumresonator) tuned to a determined frequency;

FIG. 10 schematically illustrates frequency response curves of a cavity resonator tuned to three different resonant frequencies;

fig. 11 shows schematically the roof structure from fig. 5, in which the acoustic sensors are equipped with microphones; and is

Fig. 12 schematically shows the roof structure from fig. 5, in which the acoustic sensors are equipped with solid-state sound-transmitting receivers.

The inventive idea provides for: the additional information is used by detecting signals from acoustics in the environment of the vehicle. Acoustic sensors with sound receivers are used here, which are neither arranged on the vehicle exterior nor in the vehicle interior. Instead, a cavity is used in the vehicle, which takes advantage of the weather-proof interior space without having to endure the acoustic disturbing environmental disadvantages of the passenger compartment. For this purpose, cavities already present in the vehicle body are suitable in principle, for example cavities in the vehicle door or in the roof structure (which are used in highly automated vehicles). In addition, the body of the vehicle is also adapted for the use of such acoustic sensors, wherein, for example, the roof structure in an autonomous vehicle is optimized in such a way that: so that the roof construction is particularly well suited for sound reception as an amplifying cavity. Typical wavelengths of sound and thus the geometrical size of the cavity are in the order of 1m and less.

In principle, instead of a microphone, a solid-state acoustic receiver (such as, for example, an acceleration receiver) can also be used for converting the acoustic signal into a corresponding sensor electrical signal. They are applied on the inside of the outer wall of the vehicle, such as for example the inside of the door or roof structure. The vehicle outer wall thus becomes part of the conversion element, wherein the geometry and the material together determine the propagation properties.

Fig. 1 shows the basic concept of identifying and locating external sound sources by means of a sensor system installed in a vehicle 200. The vehicle 200 has a sensor system 101, which comprises four

acoustic sensors

110, 120, 130, 140, which are arranged on

different sides

201, 202, 203, 204 of the vehicle 200. Two of the

sensors

130, 140 are arranged in two opposite vehicle doors, the other acoustic sensor 110 is arranged in the front region of the vehicle 200, and the fourth acoustic sensor is arranged in the rear region of the vehicle 200. This particular arrangement makes it possible to locate sound sources from outside in all directions well. In principle, other sensor arrangements or sensor arrays are also possible here. As is also shown in fig. 1, the

acoustic sensors

110, 120, 130, 140 of the vehicle 200 receive an acoustic signal 311 of a further vehicle 300 traveling behind the vehicle 200. The further vehicle 300 is, for example, an emergency vehicle or emergency vehicle (Einsatzwagen) which is equipped with a corresponding special signal device 310 for outputting an acoustic special signal 311. The acoustic signal 311 received by the sensor system 101 of the vehicle 200 is evaluated in a specially provided control device 150 of the vehicle 200, wherein the control device 150 is able to recognize the

signal source

310 or 300 and to determine the relative position of the signal source with respect to the vehicle 200.

Fig. 2 furthermore schematically shows a block diagram of the sensor device 100 from the vehicle 200 of fig. 1. As can be seen here, the

acoustic sensors

110, 120, 130, 140, after receiving the acoustic signal 311, each forward the corresponding sensor signal to the control device 150, which is connected to the acoustic sensors 110 to 140 by means of corresponding signal lines. In the exemplary embodiment shown here, the control device 150 is a separate control unit which forwards additional information resulting from the evaluation of the acoustic signal 311 via a corresponding data line, for example, to a central control unit 270 of the vehicle. The central control unit 270 can execute the corresponding control process of the vehicle 200 by means of the additional information obtained. In order to obtain as short a signal transmission time as possible, it can be advantageous: the control device 150 is arranged in the immediate vicinity of the

acoustic sensors

110, 120, 130, 140. This also increases the EMV robustness (EMV-Robushiet). The transmission of the signal to the controller can optionally transmit an analog signal which is sampled either analog or digitally. Particularly preferred in this respect are: the control device 150 is integrated into the roof structure 250.

Fig. 3 shows a schematic representation of the vehicle from fig. 1. It can be seen here that the first acoustic sensor 110 is arranged in a front region 201 of the vehicle, for example in the engine hood. Furthermore, a second acoustic sensor 120 is arranged in a rear region 202 of the vehicle 200, for example in a trunk lid. The third acoustic sensor 130 is arranged in the vehicle door 260 on the right vehicle side 203. A fourth acoustic sensor 140, which is not visible here, is accordingly arranged in the left door.

Fig. 4 shows an alternative arrangement of the sensor system 101 in a roof structure 250 of the vehicle 200. The roof structure 250 is constructed in a box-shaped manner, the

acoustic sensors

110, 120, 130, 140 being arranged on

different sides

201, 202, 203, 204 of the roof structure 250. Such roof structures 250 are already used in autonomous vehicles to mount environmental sensors, for example for Lidar sensors. In principle, however, such a roof structure 250 can also be provided as an optional accessory, which can be retrofitted to a vehicle without a corresponding roof structure. The roof structure 250 is subsequently understood as a part of the vehicle 200. In this regard, the exterior wall of the roof structure 250 forms a portion of the exterior vehicle wall 210.

A schematic illustration of the roof structure 250 from fig. 4 is shown in fig. 5. In the present exemplary embodiment, the roof structure 250 is of box-shaped design and has a substantially rectangular bottom surface. The sensor system 101 comprises four

acoustic sensors

110, 120, 130, 140, which are arranged in cavities in the interior of the roof structure 250, behind the outer walls 201 of the roof structure 250. The cavity can be divided into partial regions — front/rear/left/right, which are separated from one another by partition walls. In order to achieve as large an amplification effect as possible, it is advantageous: a separate cavity is provided for each

acoustic sensor

110, 120, 130, 140 and is designed cylindrically. Thus, multipath propagation of the acoustic wave is prevented extremely effectively. It has proven to be particularly advantageous structurally to mount the sensors in the central region of the respective vehicle outer wall. The acoustic sensors are preferably arranged in pairs on mutually

opposite sides

201, 202, 203, 204 of the roof structure 250. Depending on the application, the number and arrangement of the acoustic sensors of the sensor system 101 can in principle be different here.

Fig. 6 shows a simplified embodiment of the roof structure 250, which comprises only two

acoustic sensors

110, 120, compared to the variant from fig. 5. The first acoustic sensor 110 is arranged on the front side 201 of a box-shaped roof structure 250, and the second acoustic sensor 120 is arranged on the rear side 202 of the roof structure 250.

In principle, different instruments (such as, for example, a microphone or a solid-state sound transmitter) can be used as sound receivers for the acoustic sensors. Fig. 7 shows a first embodiment of the acoustic sensor 110, which uses a microphone 111 as a sound receiver. The microphone 111 is arranged in a cavity 112, which is delimited on one side by a vehicle outer wall 210. The cavity 112 for amplifying a specific frequency is designed in the present exemplary embodiment as a cylinder, wherein the microphone 111 is arranged on an end face 113 of the cylinder-shaped cavity 112 opposite the vehicle outer wall 210. The cavity 112, which serves as an acoustic resonator, furthermore has a functional layer 114 for matching the acoustic impedance, which is arranged on the inner side 211 of the vehicle outer wall 210. The functional layer 114 is preferably designed as a λ/4 layer, which is made of a suitable material and has a suitable layer thickness. When using a microphone as a sound receiver, the microphone is mounted within the roof structure as vibration-proof as possible via a suitable decoupling element (entkopplungselement) on the cavity side wall 113 opposite the vehicle outer wall 210 or directly on the vehicle outer wall 210.

Fig. 8, in contrast, shows an alternative embodiment of the acoustic sensor 110, in which the sound receiver 111 is designed in the form of a solid sound receiver. The solid sound receiver 111 is preferably arranged here directly on the inner side 211 of the vehicle outer wall 210. The acoustic sensor 110 likewise comprises a cavity 112, which is designed in the form of a cylinder in the present exemplary embodiment, as an acoustic resonator.

The cavities 112 of the acoustic sensor 110 from fig. 7 and 8 are preferably each designed for amplification of a specific frequency. The acoustic properties of such an acoustic cavity resonator are determined here primarily by the geometry of the cavity resonator and in particular by the length of the cavity resonator. Other properties, such as, for example, surface properties or materials, can also jointly determine the acoustic properties of the cavity resonator (akustisches Verhalten). The cavity resonator is characterized in that: in the space between the outer wall and the inner wall, standing waves (stehende Welle) are generated by constructive interference and thus additional amplification effects. The dimensions of the cavity resonator must be shaped here in such a way that: such that the length of the cavity resonator corresponds to L = n · λ/2+ λ/4. If amplification of a plurality of frequencies or a range of frequencies is to be achieved, it is advantageous: a compromise is set forth for the length L by the above formula. However, negative interference for the desired frequency, which leads to the cancellation of the sound waves concerned, must be avoided anyway.

The frequency response curves of the

cavity resonators

112, 122, 132, 142 tuned to a determined frequency f1 are shown schematically in fig. 9. Due to the structural interference, the

cavity resonators

112, 122, 132, 142 exhibit a particularly high amplification G in their range of the resonant frequency f1, which amplification G drops off sharply on both sides. The frequency ranges which are further away are in this case subject to a significantly lower amplification.

Fig. 10 shows a schematic illustration of the frequency response curves of the

cavity resonators

112, 122, 132, 142 tuned to a total of three resonance frequencies f1, f2, f 3. The partial overlapping of the frequency response curves by the respective resonance frequencies f1, f2, f3 results in a relatively high amplification in the entire central frequency range, while the lower and upper frequency ranges are amplified significantly lower by the

cavity resonators

112, 122, 132, 142, respectively.

The resonance properties of the

cavities

112, 122, 132, 142 of the

acoustic sensors

110, 1209, 130, 140 and, if appropriate, of the vehicle outer wall 210 separating the cavities from the vehicle environment can also be tuned to the following frequencies: this frequency is typical for certain driving states or acoustic signals. These are calculated, for example, as acoustic special signals of emergency vehicles and emergency vehicles. For the beep sound in germany (Tat uta), it would therefore be of interest to optimize for both frequencies 400 and 700 Hz. This frequency is calculated from the german standard (DIN-Norm) and furthermore it is sought to increase the frequency by means of the doppler effect when assuming a movement in opposite directions. For the two frequencies 400 and 700Hz, the formula shown above is used, thus yielding the optimum length L (in meters, respectively) of the cavity resonator given in the following table.

Hz	m	n=1	n=2	n=3
					400	0.85	0.64	1.06	1.49
700	0.486	0.36	0.61	0.85

As can be seen from the above table, the length 0.64m for 400Hz and 0.61m for 700Hz are relatively closely adjacent. A cavity with said length L equal to 0.625m is therefore suitable as an optimum compromise, whereby the length almost reaches an optimum value for both frequencies. Alternatively to the above example, additional frequencies can also be calculated in the design, also taking into account the doppler shift. In principle, in addition to the fundamental mode (Grundmode) or the fundamental frequency, the resonance behavior of the resonator can also be designed using the upper mode (Obermode) or the upper frequency (oberequenz) of the signal. Since the upper mode or upper frequency is typically in a higher frequency range, the detection of this upper mode or upper frequency is rarely disturbed very strongly by typical driving noises. Thereby yielding a better signal-to-noise ratio depending on the usage scenario. In case a solid acoustic receiver is used instead of a microphone, the housing becomes part of the transducer. The geometry and material therefore determine the propagation properties.

An advantageous variant results when the dimensions and materials of the vehicle outer wall are selected in this way: such that the vehicle outer wall has one or more natural frequencies in the range of the acoustic signal to be detected. This enables an amplification effect for the useful signal.

Typical interesting frequency ranges are in the range of 200Hz to 1kHz for voice detection and in the range of the transmission frequency (400 Hz and 700Hz in Germany, 300 Hz-1.9 kHz in the United states, etc.) for the detection of emergency signals, or the corresponding upper mode or upper frequency of the signal to be detected.

The size, thickness and rigidity of the vibrating plate (vehicle outer wall) are decisive for the location of the natural resonance. By means of these properties, the vehicle outer wall can be constructed in such a way that: so that multiple modes (and hence intrinsic resonances) are also excited.

Alternatively, the vehicle outer wall can be formed by a suitable production method, such as, for example, CFK doffing (CFK favern), in such a way that: resulting in a heterogeneous conflict (innomogene streitiggkeit). This makes it possible to introduce a plurality of dies into the component concerned in a targeted manner.

It is particularly advantageous here when the modes lie in the interval between 200Hz and 2 kHz.

Further advantages when using a solid acoustic receiver are: a park rub (Parkrempler) (collision) can be detected by the sensor. In highly automated vehicles, this information is important for assessing the functionality of all sensors in the vehicle. This enables a disorder recognition (Dejustigeerkennung) to be carried out in a simple manner.

Fig. 11 schematically shows the roof structure 250 from fig. 5, in which the

acoustic sensors

110, 120, 130, 140 are each equipped with a

sound receiver

111, 121, 131, 141 in the form of a microphone according to the embodiment from fig. 7. Fig. 12, in contrast, schematically shows the roof structure 250 from fig. 5, in which the

acoustic sensors

110, 120, 130, 140 are each equipped with a

sound receiver

111, 121, 131, 141 in the form of a solid-state sound transmitter according to the embodiment from fig. 8.

Claims

1. A sensor device (100) for detecting acoustic signals (311) in the environment of a vehicle (200), comprising:

- at least one acoustic sensor ( 110 , 120 , 130 , 140 ) with a sound receiver ( 111 , 121 , 131 , 141 ) for detecting acoustic signal sources ( 310 ) of the acoustic signal ( 311 ), wherein the sound receiver ( 111 , 121 , 131 , 141 ) is arranged in a cavity ( 112 , 122 , 132 , 142 ) of the vehicle ( 200 ), the the cavity is defined on at least one side by the outer wall (210) of the vehicle (200); and

- a control device ( 150 ) for evaluating the detected acoustic signal ( 311 ), wherein the control device ( 150 ) is designed to identify at least the a source of the acoustic signal (310), and the direction and/or position of the signal source relative to the vehicle (200) is determined.

2. The sensor device (100) according to claim 1, wherein the cavity (112, 122, 132, 142) is designed as a resonator for amplifying at least _one predetermined frequency (f1, f ₂ , _f3 ).

3. The sensor device (100) according to claim 1 or 2, wherein the outer wall (210) of the vehicle (200) bounding the cavity (112, 122, 132, 142) is It is designed as a resonator for at least one predetermined frequency (f ₁ , f ₂ , f ₃ ).

4. The sensor device (100) according to claim ₂ or ₃ , which is optimized for detection of frequencies (f1, f2, _f3 ) for acoustic signals The acoustic signal (311) of at least one of the sources (310) is typically:

- emergency vehicles or special signaling devices for emergency vehicles;

- tunnel entrance;

- the cry of the child;

- crossroads;

- Traffic accident.

5. The sensor device (100) according to any of the preceding claims, wherein the cavity (112, 122, 132, 142) of the at least one acoustic sensor (110, 120, 130, 140) is cylindrical ground, and wherein the sound receivers ( 111 , 121 , 131 , 141 ) are constructed in the form of microphones that are arranged in the cylindrical cavity ( 112 , 122 , 132 , 142 ), and all on the opposite side wall (133) of the outer wall (210) of the vehicle (200).

6. The sensor device (100) according to claim 5, wherein the at least one acoustic sensor (110, 120, 130, 140) comprises a functional layer (114, 124, 134, 144) for matching the acoustic impedance, the functional layer is arranged on the inner side (211) of the outer wall (210) of the vehicle (200), the outer wall defining the cavity (112, 122, 132, 142).

7. The sensor device (100) according to any one of claims 1 to 4, wherein the sound receiver (111, 121, 131, 141) Constructed in the form of a structure-borne sound receiver arranged on the inner side (211) of an outer wall (210) of the vehicle (200), the outer wall defining the cavity ( 112, 122, 132, 142).

8. The sensor device (100) according to any of the preceding claims, wherein the sensor device (100) comprises a system (101) of a plurality of acoustic sensors (110, 120, 130, 140) ), the acoustic sensors are arranged on one or more sides (201, 202, 203, 204) of the vehicle (200) at a distance from each other.

9 . The sensor device ( 100 ) according to claim 8 , wherein the acoustic sensors ( 110 , 120 , 130 , 140 ) are respectively arranged in pairs on respectively opposite sides of the vehicle ( 200 ). 10 . (201, 202, 203, 204).

10. The sensor device (100) according to any of the preceding claims, wherein the at least one acoustic sensor (110, 120, 130, 140) is arranged at a door (230) of the vehicle (200) ) or in the roof structure (250) of the vehicle.

11. Control device (150) for a sensor device (100) according to any one of claims 1 to 10 for detecting acoustic signals in the environment of a vehicle (200),

In this case, the control device ( 150 ) is designed to evaluate a sensor signal which is arranged by at least one of the outer walls ( 210 ) of the vehicle ( 200 ) due to the received acoustic signal ( 311 ). Acoustic sensors ( 110 , 120 , 130 , 140 ) at the inner side ( 211 ) are provided to identify an acoustic signal source ( 310 ) that emits said acoustic signal ( 311 ), and to determine the relative to the direction and/or location of the vehicle (200).