Sound detector for measuring the vibration of a surface, and vehicle comprising such a sound detector
Patent Information
- Authority / Receiving Office
- WO · WO
- Patent Type
- Applications
- Current Assignee / Owner
- ROBERT BOSCH GMBH
- Filing Date
- 2025-11-03
- Publication Date
- 2026-06-18
AI Technical Summary
Current ultrasonic distance measurement systems in vehicles are exposed to external environmental influences and require recesses in the vehicle bodywork, affecting design and requiring precise installation, which increases manufacturing effort.
A sound detector using a laser diode, photodiode, and control unit is positioned inside the vehicle, generating and detecting laser beams to measure vibrations of a measuring wall without direct contact, allowing for robust and versatile placement.
The sound detector is protected from external influences, maintains vehicle design integrity, reduces manufacturing complexity, and provides versatile positioning options while accurately measuring vibrations.
Smart Images
Figure EP2025081699_18062026_PF_FP_ABST
Abstract
Description
[0001] R.412154
[0002] - 1 -
[0003] Description
[0004] title
[0005] Sound detector for measuring the vibration of a surface, and a vehicle having such a sound detector
[0006] State of the art
[0007] Current devices for measuring ambient sound, particularly ultrasound, are usually embedded in the outer skin of vehicles. Embedding means that a recess is created in the vehicle's bodywork, and the receiver of the device for measuring the ambient ultrasound is inserted into this recess. This always creates a gap between the surface of the ultrasound sensor and the surrounding bodywork. Furthermore, the receiver of the ultrasound device is exposed to external environmental influences, such as the weather. Current ultrasonic distance measurement systems consist of a transmitter and a receiver. The transmitter is designed to emit an ultrasonic signal to the vehicle's surroundings via a surface.This emitted primary ultrasound beam is reflected by an object in the vicinity and reflected back to the receiver as a secondary ultrasound beam. The receiver has a surface that is set into vibration by the secondary ultrasound beam. The transmitter and / or the receiver are designed as piezoelectric elements, so that a vibration of this surface is directly converted into an electrical signal via the piezoelectric element. By determining the difference between the emission time of the primary ultrasound beam and the reception time of the secondary ultrasound beam, the distance of an object to the transmitter and the receiver can be determined. R.412154.
[0008] - 2 -
[0009] Disclosure of the invention
[0010] The sound detector according to the invention, in particular the ultrasound detector, with the features of claim 1, has the advantage over the known device that the sound detector can be arranged inside the vehicle, i.e., behind the bodywork. Thus, the vehicle design is not affected by the sound detector, and more placement options are available. Furthermore, this results in the sound detector being significantly better protected from external influences and therefore more robust against them. This also reduces the manufacturing effort of the vehicle, as no openings need to be provided in the outer skin. Moreover, this reduces the manufacturing effort of the vehicle because precise insertion of the ultrasound transducer into the opening of the vehicle's outer skin is no longer necessary.
[0011] According to the invention, this is achieved by the sound detector comprising a laser diode with a laser cavity, a photodiode, a measuring wall, and a control unit. The laser diode is configured to generate a first primary laser beam in its laser cavity. The laser cavity is configured to increase the intensity of the first primary laser beam to a predetermined intensity and to emit the first primary laser beam. The laser cavity is configured to receive a secondary laser beam reflected from the measuring wall and to superimpose it with a second primary laser beam. When the measuring wall moves, particularly vibrates, a frequency shift of the secondary laser beam occurs, resulting in a beat frequency. The photodiode is configured to detect this beat frequency and to convert the frequency shift of the secondary and second primary beams into an electrical signal.The control unit is designed to receive and / or retrieve the electrical signal from the photodiode in order to determine movement of the measuring wall by means of a temporal evaluation of the electrical signal.
[0012] In other words, it is an acoustic detector designed to determine the movement, in particular the vibration, of a surface of the measuring wall. For this purpose, the acoustic detector generates a first primary beam in its laser cavity via the laser diode. Within the laser cavity, the intensity of the laser beam is increased to a predetermined value. This first R.412154
[0013] - 3 -
[0014] The primary laser beam, with its increased laser intensity, is emitted from the laser cavity into the surrounding environment. The first primary laser beam, emitted from the laser cavity, is directed at the measuring wall. At the measuring wall, the first primary laser beam is reflected and returned to the laser cavity as a secondary laser beam. Meanwhile, a second primary laser beam is generated within the laser cavity of the laser diode. Within the laser cavity, the second primary laser beam and the received secondary laser beam are superimposed. This results in a so-called beat frequency, if the measuring wall moves at the point of reflection. The photodiode detects this beat frequency and converts it into an electrical signal. The control unit is electrically connected to the photodiode and can retrieve and / or receive this electrical signal.The control unit evaluates the electrical signal and can use it to determine, for example, a beat frequency. The control unit is configured to use this beat frequency to determine the movement of the measuring wall. Furthermore, the control unit is connected to the laser diode and the laser cavity for signal exchange. The control unit is configured to activate the emission of a primary laser beam by the laser diode.
[0015] An advantage of this embodiment is that the sound detector is configured to detect a deflection and / or vibration of the measuring wall without being in direct contact with it. Thus, the sound detector is able to detect vibrations of the measuring wall caused by sound waves, particularly those resulting from airborne sound. In this way, the sound detector can measure a sound wave striking the measuring wall. Therefore, the sound detector, designed as an ultrasonic detector, does not need to be in direct contact with the ultrasound that set the measuring wall in motion.
[0016] The dependent claims describe preferred embodiments of the invention.
[0017] Preferably, the acoustic detector includes a collimating lens or a focusing lens. The collimating lens or focusing lens is arranged between the measuring wall and the laser cavity. The collimating lens or focusing lens is configured to collimate or focus the first primary laser beam emitted from the laser cavity. An advantage of this embodiment may be, R.412154
[0018] - 4 - that the measurement signal is improved by means of the collimating lens or the focusing lens.
[0019] The sound detector preferably incorporates a MEMS mirror. A MEMS mirror is a microelectromechanical mirror.
[0020] The MEMS mirror is configured to direct the first primary laser beam emitted from the laser cavity onto a first measuring point on the measuring wall and to direct a secondary laser beam reflected from the first measuring point back towards the laser cavity. An advantage of this embodiment is that the laser cavity can be positioned arbitrarily relative to the measuring wall, since the first primary laser beam or the secondary laser beam can be deflected by the MEMS mirror.
[0021] Advantageously, the MEMS mirror is pivotable about at least one axis, allowing the first primary laser beam to be directed at at least one second measurement point on the measuring wall. An advantage of this embodiment is that the first primary laser beam of the pivotable MEMS mirror can scan multiple points on the measuring wall as the first measurement point. This makes it possible to detect asymmetrical movement of the measuring wall. Using a single acoustic detector, vibrations can thus be measured in several point-like areas or over a continuous, extended area. In this way, directional information regarding a sound source or an acoustic reflection point of an object within the detection range, for example, around a vehicle, can also be derived using a single acoustic detector.
[0022] The sound detector advantageously features a first optical waveguide. This first optical waveguide is configured to direct a first primary laser beam originating from the laser cavity to a first measuring point on the measuring wall and to direct a secondary laser beam reflected from the first measuring point back to the laser cavity. An advantage of this embodiment can be that the influence of external factors on the guidance of the first primary laser beam and / or the secondary laser beam is reduced or completely eliminated. (R.412154)
[0023] - 5 - is prevented. Thus, this embodiment has the advantage of being particularly robust against external disturbances.
[0024] Preferably, the acoustic detector comprises a second optical waveguide and an optical switch. The second optical waveguide is configured to direct the first primary laser beam, originating from the laser cavity, to a second measuring point on the measuring wall and to direct a secondary laser beam reflected from the second measuring point to the laser cavity. The second measuring point differs from the first measuring point in its position on the measuring wall. The optical switch is configured to receive the first primary laser beam, originating from the laser cavity, and transmit it to the first optical waveguide and / or the second optical waveguide. The optical switch is configured to receive the secondary laser beam, originating from the first optical waveguide and / or the second optical waveguide, and transmit it to the laser cavity.One advantage of this embodiment is that, by means of the optical switch and the second optical waveguide, it is possible to simultaneously direct the first primary laser beam to both a first and a second measuring point. Alternatively or additionally, it is possible, by means of the optical switch and the first and second optical waveguides, to direct the first...
[0025] The primary laser beam can be switched back and forth arbitrarily between the first measuring point and the second measuring point.
[0026] Particularly preferably, the first measuring point is surrounded by a first measuring wall damping element. In particular, the first measuring wall damping element is formed in a ring shape around the first measuring point. The first measuring wall damping element is applied to the measuring wall and exhibits higher damping than the measuring wall. Alternatively or additionally, the second measuring point is surrounded by a second measuring wall damping element. In particular, the second measuring wall damping element is formed in a ring shape around the second measuring point. The second measuring wall damping element is applied to the measuring wall and exhibits higher damping than the measuring wall. The first measuring wall damping area and / or the second measuring wall damping area are formed, for example, by a layer of butyl rubber. An advantage of this embodiment can be that the vibration of the R.412154 can be influenced by means of the first measuring wall damping area and / or the second measuring wall damping area.
[0027] - 6 - The vibration of the remaining measuring wall reduces the impact of external disturbances on the measurement of the movement at the first and / or second measuring point. This allows for a reduction in the influence of external disturbances on the measurement of the movement at the respective measuring points. The measuring wall damping elements serve in particular to dampen disruptive structure-borne noise in the vicinity of the measuring point. The first measuring wall damping element and / or the second measuring wall damping element are arranged only on one side of the measuring wall. This ensures that the measuring wall damping elements are not visible from one side.
[0028] Advantageously, the first optical waveguide has an integrated gradient lens for beam shaping. The gradient lens is then configured, for example, to focus the primary laser light as it exits the first optical waveguide, particularly at the measurement point. Alternatively or additionally, the gradient lens is configured to focus the secondary laser light as it exits the first optical waveguide, particularly also at the optical switch and / or the laser cavity. An advantage of this embodiment can be that the gradient lens allows for simple guidance and focusing of the primary laser light and / or the secondary laser light.
[0029] In an advantageous embodiment, a resonator is mounted on the measuring wall. The resonator is connected or coupled to the measuring wall, in particular via a coupling element. The resonator is adapted to at least one frequency range, for example, ultrasound or audio signals such as the siren frequency of emergency vehicles. Preferably, the resonator is arranged on the measuring wall. The resonator is designed to selectively amplify vibrations of specific frequencies for improved detectability.
[0030] Furthermore, the invention comprises a vehicle comprising a fairing part and a sound detector according to one of the preceding embodiments. The fairing part constitutes the measuring wall of the sound detector. The first measuring point is arranged on an inner surface of the fairing part. The measuring wall corresponds in particular to said inner surface of the fairing part. An advantage of this embodiment can be that the sound detector is thus not arranged in a recess of the fairing part. Instead, R.412154
[0031] - 7 - The sound detector is positioned on the inside of the cladding panel and is therefore invisible from the outside and protected from external influences. This makes the sound detector more robust against external interference.
[0032] Preferably, the vehicle has an ultrasonic transmitter. The ultrasonic transmitter is configured to emit a primary ultrasonic beam into the vehicle's surroundings. The fairing component is configured to be set into vibration by at least a portion of a secondary ultrasonic beam reflected into the surroundings.
[0033] Drawings
[0034] Exemplary embodiments of the invention are described in detail below with reference to the accompanying drawings. The drawing shows:
[0035] Figure 1 is a schematic representation of a vehicle comprising a sound detector according to an embodiment of the invention.
[0036] Figure 2 shows a schematic representation of a sound detector according to a first embodiment of the invention.
[0037] Figure 3 shows a schematic representation of a sound detector according to a second embodiment of the invention.
[0038] Figure 4 shows a schematic representation of a sound detector according to a third embodiment of the invention.
[0039] Figure 5 shows a schematic representation of a sound detector according to a fourth embodiment of the invention.
[0040] Figure 6 shows a schematic representation of a sound detector according to a fifth embodiment of the invention.
[0041] Figure 7 is a schematic representation of a sound detector according to a sixth embodiment of the invention, R.412154
[0042] - 8 -
[0043] Figure 8 shows a schematic representation of a sound detector and a
[0044] Sound transducer according to an embodiment of the invention,
[0045] Figure 9 shows a schematic representation of a sound transmitter and a
[0046] sound detector according to an embodiment of the invention, and
[0047] Figure 10 shows a schematic representation of an alternative embodiment of a measuring wall of the sound detector according to one of the embodiments of the invention.
[0048] Exemplary embodiments of the invention
[0049] Preferably, all elements, units and / or assemblies in all figures have the same reference numerals.
[0050] Figure 1 shows a schematic representation of a vehicle 10 with a fairing panel 11 and a sound detector 100 arranged in the fairing panel according to an embodiment of the invention and an ultrasonic transmitter 20. The sound detector 100 can be positioned anywhere on the vehicle 10, for example, also laterally in the vehicle door. This provides an advantageous, design-neutral, and versatile positioning option.
[0051] Figure 2 shows a schematic representation of an acoustic detector 100 according to a first embodiment of the invention. The acoustic detector 100 comprises a laser diode 110 with a laser cavity 130, a photodiode 120, a measuring wall 140, and a control unit 150 (not shown). The laser diode 110 is configured to generate a first primary laser beam 210 in its laser cavity 130. The laser cavity 130 is configured to increase the intensity of the first primary laser beam 210 to a predetermined intensity and to emit the first primary laser beam 210. The laser cavity 130 is configured to receive a secondary laser beam 220 reflected from the measuring wall 140 and to superimpose it with a second primary laser beam 210 following the first primary laser beam 210. If the measuring wall 140 moves, this superposition results in a beat frequency.The photodiode 120 is set up to detect the beat frequency and to use the beat frequency to create a frequency shift between the secondary laser beam 220 and the second primary laser beam 210 R.412154.
[0052] - 9 - to detect and convert into an electrical signal. The control unit 150 is configured to receive and / or retrieve the electrical signal from the photodiode 120 and to determine any movement of the measuring wall 140 by means of a temporal evaluation of the electrical signal. Here, the opening of the laser cavity is oriented such that the first primary laser beam 210 leaving the laser cavity 130 is directed in a straight line to the first measuring point 142.
[0053] The first measuring point 142 is surrounded by a ring-shaped first measuring wall damping element 182. This first measuring wall damping element 182 is attached to the measuring wall 140. The first measuring wall damping element 182 has a higher damping than the measuring wall 140 itself. This allows vibrations of the measuring wall 140 to still be detected at the first measuring point 142, while interfering effects such as structure-borne noise in the vicinity of the first measuring point 142 are damped. For example, the first measuring wall damping element 182 is made of butyl rubber.
[0054] Figure 3 shows a schematic representation of an acoustic detector 100 according to a second embodiment of the invention. The second embodiment of the acoustic detector 100 has essentially similar features to the first embodiment. In contrast to the first embodiment of the acoustic detector 100, the opening of the laser cavity 130 in the second embodiment of the acoustic detector 100 is oriented transversely to a position of the measuring point 142 on the measuring wall 140. The acoustic detector 100 additionally includes a MEMS mirror 150. The MEMS mirror 150 is arranged in the light path of the first primary laser light 210 as it exits the laser cavity 130. Thus, the MEMS mirror is able to deflect the first primary laser light 210 emitted from the laser cavity 130.The MEMS mirror is configured to direct the first primary laser light 210 emitted from the laser cavity 130 onto a first measuring point 142 on the measuring wall 140 and to return a secondary laser beam 220 reflected from the first measuring point 142 to the laser cavity 130. The MEMS mirror 150 has at least one axis 151. The MEMS mirror 150 is pivotably mounted about this axis 151, so that the first primary laser beam 210 can be pivoted across the measuring wall 140. R.412154.
[0055] - 10 -
[0056] Figure 4 shows a schematic representation of an acoustic detector 100 according to a third embodiment of the invention. The third embodiment of the acoustic detector 100 has similar features to the first and second embodiments of the acoustic detector 100. The MEMS mirror 150 is configured to align the first primary laser beam 210 to a second measuring point 144 and to a third measuring point 146 on the measuring wall 140.
[0057] Figure 5 shows a schematic representation of an acoustic detector 100 according to a fourth embodiment of the invention. The fourth embodiment of the acoustic detector 100 has similar features to the first to third embodiments of the acoustic detector 100. The acoustic detector 100 has a first optical waveguide 162. The first optical waveguide 162 is configured to direct a first primary laser beam originating from the laser cavity 130 to a first measuring point 142 on the measuring wall 140. The first optical waveguide 162 is configured to direct a secondary laser beam reflected from the first measuring point 142 to the laser cavity 130. The opening of the laser cavity 130 can be arbitrarily positioned relative to the surface of the measuring wall 140, since the outgoing first primary laser beam 210 is guided by the first optical waveguide 162 to the measuring point 142 on the measuring wall 140.
[0058] Figure 6 shows a schematic representation of an acoustic detector 100 according to a fifth embodiment of the invention. The fifth embodiment of the acoustic detector 100 has similar features to the first to fourth embodiments of the acoustic detector 100. The acoustic detector has a second optical waveguide 164 and a third optical waveguide 166. The second optical waveguide 164 is configured to direct the first primary laser beam, originating from the laser cavity 130, to a second measuring point 144 on the measuring wall 140 and to direct a secondary laser beam, reflected from the second measuring point 144, to the laser cavity 130. The third optical waveguide 166 is configured to direct the first primary laser beam, originating from the laser cavity 130, to a third measuring point 146 on the measuring wall 140, and to direct a secondary beam, reflected from a third measuring point 146, to the laser cavity 130. R.412154
[0059] - 11 -
[0060] Figure 7 shows a schematic representation of an acoustic detector 100 according to a sixth embodiment of the invention. The sixth embodiment of the acoustic detector 100 has similar features to the first through fifth embodiments of the acoustic detector 100. The acoustic detector 100 includes an optical switch 170. The optical switch 170 is configured to receive the first primary laser beam emanating from the laser cavity 130 and to transmit it to the first optical waveguide 162 and / or the second optical waveguide 164 and / or the third optical waveguide 166. Alternatively or additionally, the optical switch 170 is configured to transmit the secondary laser beam emanating from the first optical waveguide 162 and / or the second optical waveguide 164 and / or the third optical waveguide 166 to the laser cavity 130.
[0061] Figure 8 shows a schematic representation of a sound detector 100 according to a first embodiment of the invention with a sound transmitter 20, for example, an ultrasonic transducer. Instead of the sound detector 100 according to the first embodiment, an arrangement of the sound detector 100 according to one of the second to sixth embodiments would also be conceivable. The sound transmitter 20 is arranged at a distance from a panel 11 of the vehicle. Here, the sound transmitter 20 is, for example, installed without being concealed, i.e., also embedded in the panel 11 in a conventional manner. The sound transmitter 20 is configured to emit a primary sound beam 22 into the surroundings 5. The emitted primary sound beam 22 is reflected by an object 23 in the surroundings 5 and reflected back to the panel 11 as a secondary sound beam 24. The panel 11 is set into vibration by the secondary sound beam 24.
[0062] The measuring wall 140 is an inner wall of the paneling part 11, so that it is not apparent from the outside that a detector or sensor is present. For example, in the case of vehicle 10, the acoustic detector 100 is located on the inside of an outer skin of vehicle 10 formed by the paneling part 11 and is not visible from the outside. The first measuring point 142 is located on the inner side 11a of the paneling part 11, i.e., the measuring wall 140. The first primary laser beam 210 emitted by the laser cavity 130 is reflected onto the first measuring point 142 on the inside of the paneling part 11 and returned to the laser cavity 130 as a secondary laser beam 220. R.412154
[0063] - 12 -
[0064] Figure 9 describes an arrangement of a sound detector 100 according to a first embodiment of the invention and a sound transmitter 20, which is, for example, an ultrasonic transducer. In this embodiment, the sound transmitter 20 is arranged behind the trim panel 11 of the vehicle 10. The sound transmitter 20 is configured to send the sound signal through the trim panel 11 into an environment 5. Thus, in this embodiment, both the sound transmitter 20 and the sound detector 100 are arranged behind a trim panel 11 of the vehicle 10 and are therefore invisible from the outside and protected from external influences.
[0065] Figure 10 schematically shows an alternative embodiment of the measuring wall 140, which can alternatively be used in the embodiments described above. In this embodiment, a resonator 230 is attached to the measuring wall 140. The resonator 230 is connected to the measuring wall 140 via a coupling element 231. The resonator 230 is designed to selectively amplify vibrations of certain frequencies for improved detectability. For example, the resonator 230 is adapted to at least one frequency range, such as ultrasound or audio signals like the siren frequency of emergency vehicles. In this embodiment as well, the measuring wall 140 is, for example, an inner wall of the cladding part 11. The resonator 230 and the coupling element 231 are not visible from the outside. Thus, it is not visible from the outside that a detector or sensor is located on the inner side 11a of the cladding part 11.
Claims
R.412154 - 13 - Claims 1. Sound detector (100) comprising: - a laser diode (110) with a laser cavity (130), - a photodiode (120), - a measuring wall (140), and - one control unit (150), - wherein the laser diode (110) is configured to generate a first primary laser beam (210) in its laser cavity (130), - wherein the laser cavity (130) is configured to increase the intensity of the first primary laser beam (210) to a predetermined intensity, and to emit the first primary laser beam (210), - wherein the laser cavity (130) is configured to receive a secondary laser beam (220) reflected from the measuring wall (140) and to superimpose it with a second primary laser beam, wherein, when the measuring wall (140) is moved, the superposition leads to a beat frequency, - wherein the photodiode (120) is configured to detect the beat frequency and to convert a frequency shift of the secondary beam (220) to the second primary beam into an electrical signal by means of the beat frequency, and - wherein the control unit (150) is configured to receive and / or retrieve the electrical signal from the photodiode (120) in order to determine a movement of the measuring wall (140) by means of a temporal evaluation of the electrical signal.
2. Sound detector (100) according to claim 1 , characterized in that - a collimation lens or focusing lens is arranged between the measuring wall (140) and the laser cavity (130), and - wherein the collimation lens is configured to collimate the first primary laser beam (210) emitted from the laser cavity (130), or - wherein the focusing lens is configured to focus the first primary laser beam (210) emitted from the laser cavity (130). R.412154 - 14 - 3. Sound detector (100) according to one of the preceding claims, characterized by a MEMS mirror (150) which is configured to direct the first primary laser beam (210) emitted from the laser cavity (130) to a first measuring point (142) on the measuring wall (140) and to direct a secondary laser beam (220) reflected from the first measuring point (142) to the laser cavity (130).
4. Sound detector (100) according to claim 3, characterized in that the MEMS mirror (150) is pivotable about at least one axis (151) so that a first primary laser beam (210) is directed onto a second measuring point (144) can be directed on the measuring wall (140) 5. Sound detector (100) according to one of the preceding claims, characterized by a first optical waveguide (162), - wherein the first optical waveguide (162) is configured to direct the first primary laser beam (210) originating from the laser cavity (130) to a first measuring point (142) on the measuring wall (140), and - to direct a secondary laser beam (220) reflected from the first measuring point (142) towards the laser cavity (130).
6. Sound detector (100) according to one of the preceding claims, characterized by a second optical waveguide (164) and an optical switch (170), - wherein the second optical waveguide (164) is configured to direct the first primary laser beam (210) originating from the laser cavity (130) to a second measuring point (144) on the measuring wall (140) and to direct a secondary laser beam (220) reflected from the second measuring point (144) to the laser cavity (130), - wherein the optical switch (170) is configured to receive the first primary laser beam (210) emanating from the laser cavity (130) and to transmit it to the first optical waveguide (162) and / or to the second optical waveguide (164), and - wherein the optical switch (170) is set up to emit the secondary laser beam (220) from the first optical waveguide R.412154 - 15 - (162) and / or from the second optical waveguide (164) to the laser cavity (130).
7. Sound detector (100) according to one of the preceding claims, characterized in that - the first measuring point (142), in particular in an annular form, is surrounded by a first measuring wall damping element (182), wherein the first measuring wall damping element (182) is applied to the measuring wall (140), wherein the first measuring wall damping element (182) has a higher damping than the measuring wall (140), and / or - the second measuring point (144), in particular in an annular form, is surrounded by a second measuring wall damping element (184), wherein the second measuring wall damping element (184) is applied to the measuring wall (140), wherein the second measuring wall damping element (184) has a higher damping than the measuring wall (140).
8. Sound detector (100) according to one of the preceding claims, characterized in that the first optical waveguide (162) has an integrated gradient lens, - wherein the gradient lens is configured to focus the first primary laser light upon exiting the first optical waveguide (162) particularly onto the first measurement point (142), and / or - wherein the gradient lens is configured to focus the secondary laser light (220) as it exits the first optical waveguide (162) particularly onto the optical switch (170) and / or the laser cavity (130).
9. Sound detector (100) according to one of the preceding claims, characterized in that a resonator (230) is attached to the measuring wall (140), in particular via a coupling element (231), wherein the resonator is configured to selectively amplify vibrations of predetermined frequencies for better detectability.
10. Vehicle (10) comprising a fairing part (11) and a sound detector (100) according to one of the preceding claims, - wherein the cladding part (11) represents the measuring wall (140) of the sound detector (100), and R.412154 - 16 - - wherein the first measuring point (142) is located on an inside (11 a) of the cladding part (11).
11. Vehicle (10) according to claim 10, characterized by a sound transmitter (20), - wherein the sound emitter (20) is configured to emit a primary sound beam (22) to send in an environment (5) of the vehicle (10), and - wherein the cladding part (11) is arranged to be set into vibration by at least part of a secondary sound beam (24) reflected in the environment.