Systems and methods for piezoelectric diaphragm transducers for automotive microphone applications

Abstract

The present invention provides a system and method for a piezoelectric diaphragm transducer for automotive microphone applications. The present invention provides a system and method for a transducer assembly for a vehicle having a resonant surface. The transducer assembly includes a housing, a gasket connected to the housing, and a piezoelectric assembly disposed between the gasket and the housing. The gasket is configured to connect to the resonant surface to form an air gap between the resonant surface and the piezoelectric assembly.

Description

[0001] CROSS-REFERENCE TO RELATED APPLICATIONS

[0002] This disclosure claims priority to and the benefit of (i) U.S. Provisional Application No. 62 / 895,772, filed on September 4, 2019, (ii) U.S. Provisional Application No. 62 / 939,979, filed on November 25, 2019, (iii) U.S. Provisional Application No. 62 / 988,625, filed on March 12, 2020, and (iv) U.S. Patent Application No. 16 / 879,147, filed on May 20, 2020, all of which are incorporated herein by reference in their entireties. Technical Field

[0003] The present disclosure generally relates to vehicle microphones. Background Art

[0004] Conventional microphones are used in automotive control systems to provide input for various vehicle operations. However, conventional microphones can be susceptible to weather conditions when deployed outside the vehicle. Furthermore, conventional microphones can be susceptible to environmental conditions, such as heat or cold, when deployed in certain locations on the vehicle, such as in the engine compartment. Therefore, a more robust assembly is needed for use as a microphone in a vehicle. Summary of the Invention

[0005] Described herein are systems and methods for a transducer assembly for a vehicle having a resonant surface, such as a vehicle window or other vehicle surface. In some cases, the transducer assembly can include a piezoelectric crystal accelerometer configured as an input device for converting a sound-related vibration input from a rigid, resonant surface of the vehicle into an electrical output. The output can include a sound signal that can be processed into a reproduction of the original sound using a processing computer, such as, for example, a speech recognition system associated with the vehicle's automotive computer. One exemplary embodiment includes a mountable, acoustically active transducer assembly that can capture sound from outside a vehicle at a sound quality sufficient for speech recognition processing using an onboard computer system while having a relatively low noise profile associated with the signal.

[0006] The transducer assembly can be configured to function as a weather-resistant solid-state microphone device that can be mounted inside or outside a vehicle and in locations that may not typically be suitable for microphones or other input devices, such as an engine compartment. The transducer assembly can include a piezoelectric actuator, such as a type commonly used in small consumer electronics to produce buzzes, chirps, or other sound outputs. The piezoelectric actuator can be configured as an input device, where the transducer assembly can be rigidly mounted to a resonant surface, such as a car window, and use the window to receive sound vibrations and generate sound signals for processing by the car's computer.

[0007] In some cases, the transducer assembly can include a small cavity between the piezoelectric device and the glass surface on which the transducer assembly is mounted. The air gap formed by the cavity can receive dynamic motions caused by sound resonating through the glass. The piezoelectric element can receive these dynamic (in some cases subtle) motions via the air gap between the piezoelectric element and the resonating glass surface, so that the piezoelectric element can move freely in response to the dynamic motions. The piezoelectric element can sense vibrations associated with sound (e.g., a person speaking, a dog barking, engine noise, street noise, etc.) because the sound resonates through the mounting surface (e.g., car glass) and moves the piezoelectric element, which produces a signal output without interference from a contact surface spanning the entire bottom of the piezoelectric element.

[0008] In this manner, a piezoelectric element can be positioned on a flexible diaphragm, which is suspended directly above the air gap by a connection surface (such as a gasket) extending around the periphery of the flexible diaphragm. The rigid piezoelectric disc portion can receive the differential air pressure force from the physical manifestation of sound as it propagates through the resonant surface. The piezoelectric element can generate electrical pulses that can be conditioned by a bandpass filter and amplification circuitry. The output can include a conditioned electrical sound signal that can be used by a processing computer onboard the vehicle.

[0009] The transducer assembly can be electrically passive, allowing it to be mounted to an external vehicle surface and generate a low-voltage signal with negligible electromagnetic interference that would otherwise distort or interrupt the acoustic output signal. For example, the transducer assembly can include an electromagnetic shielding layer within the assembly housing that is configured to shield the low-voltage signal from crosstalk between the device and other electromagnetic forces.

[0010] The systems and methods described below can provide a weatherproof and robust sound input device for delivering a high-quality sound output signal that mimics a microphone while using a robust and inexpensive solid-state component package.These and other advantages of the present disclosure are provided in greater detail herein. BRIEF DESCRIPTION OF THE DRAWINGS

[0011] The detailed description is set forth with reference to the accompanying drawings. The use of the same reference numerals may indicate similar or identical items. Various embodiments may utilize elements and / or components other than those shown in the accompanying drawings, and some elements and / or components may not be present in various embodiments. The elements and / or components in the figures are not necessarily drawn to scale. Throughout this disclosure, singular and plural terms may be used interchangeably, depending on the context.

[0012] Figure 1 A piezoelectric diaphragm transducer device adhered to a resonant surface is depicted according to an exemplary embodiment of the present disclosure.

[0013] Figure 2 Depicted is a piezoelectric diaphragm transducer device adhered to a resonant surface having a printed circuit board (PCB) configured as a tunable mass, according to an exemplary embodiment of the present disclosure.

[0014] Figure 3 Depicted is a piezoelectric diaphragm transducer device adhered to a resonant surface having a PCB integrated within a housing wall of the device, according to an exemplary embodiment of the present disclosure.

[0015] Figure 4A A piezoelectric diaphragm transducer device adhered to a resonant surface is depicted according to an exemplary embodiment of the present disclosure, wherein the piezoelectric transducer device includes a PCB integrated within an electrically shielded housing wall of the device.

[0016] Figure 4B A piezoelectric diaphragm transducer device adhered to a resonant surface is depicted according to an exemplary embodiment of the present disclosure, wherein the piezoelectric transducer device includes a two-piece housing and an annular ring configuration.

[0017] Figure 5 Schematically depicts a method for Figures 1 to 4B An exemplary PCB circuit for any of the devices depicted in .

[0018] Figure 6 is an illustration of a rigid connection surface for the flexible diaphragm portion of the device according to an exemplary embodiment of the present disclosure.

[0019] Figure 7 is a schematic diagram of an exemplary vehicle control system according to the present disclosure, wherein the vehicle control system is configured to Figures 1 to 5 One or more devices depicted in any of the receive a sound input signal.

[0020] Figure 8A is a front view of a rearview mirror according to an embodiment of the present disclosure, wherein the transducer assembly is adhered to the inner surface of the mirror glass.

[0021] Figure 8B According to an embodiment of the present disclosure Figure 8A A partial cross-sectional view of the rearview mirror.

[0022] Figure 9 An exemplary transducer assembly rigidly adhered to a vehicle surface is depicted according to an exemplary embodiment of the present disclosure.

[0023] Figure 10 A cross-sectional view illustrates an exemplary configuration for attaching a transducer assembly to an exterior surface of automotive glass beneath a vehicle's glass bezel, according to an embodiment of the present disclosure.

[0024] Figure 11A Depicted is an exploded view of a piezoelectric diaphragm transducer device according to an exemplary embodiment of the present disclosure.

[0025] Figure 11B Depicted is a cross-sectional view of a piezoelectric diaphragm transducer device according to an exemplary embodiment of the present disclosure. DETAILED DESCRIPTION

[0026] The present disclosure will be described more fully hereinafter with reference to the accompanying drawings, in which exemplary embodiments of the disclosure are shown and are not intended to be limiting.

[0027] Figure 1 A transducer assembly 100 is depicted according to an exemplary embodiment of the present disclosure. The transducer assembly 100 can include a transducer housing 102 and an annular gasket 112 configured to be rigidly coupled to a resonant surface 116 at a base of the annular gasket 112 via an adhesive layer 114. The transducer assembly 100 can also include a flexible diaphragm 136 that separates an inner portion 106 from a cavity 109 formed by the annular gasket 112 when the annular gasket 112 is rigidly coupled to an outer portion 148 of the resonant surface 116. Thus, the flexible diaphragm 136 can be suspended above the resonant surface 116 such that an air gap 144 is formed between the flexible diaphragm 136 and the resonant surface 116. Although depicted as being generally dome-shaped, the housing and general shape of the transducer assembly 100 can be configured to be generally rectangular, oval, or another suitable shape.

[0028] In one embodiment, the piezoelectric disc assembly 133 can include a flexible diaphragm 136 and a piezoelectric disc portion 134. The piezoelectric disc portion 134 can be rigidly disposed on an interior-facing side of the flexible diaphragm 136 (e.g., on the interior portion 106 side of the flexible diaphragm 136). The piezoelectric disc assembly 133 can also include a tunable mass 138 disposed on a top surface of the piezoelectric disc portion 134. The tunable mass 138 can be rigidly coupled to the top surface of the piezoelectric disc portion 134 and sized to provide a vibration-enhancing mass for the piezoelectric disc portion 134. In some cases, the tunable mass 138 can be configured to enhance motion caused by sound resonating through the resonant surface and through the annular gasket 112 to the flexible diaphragm 136.

[0029] Those skilled in the art will appreciate that the tunable mass can be sized, shaped, and oriented within the transducer assembly, where the size, shape, and orientation are based on experimental observations of how these characteristics may affect the system response. The orientation, shape, size, substrate material, density, and fastening means of the tunable mass can be selected to enhance the vibratory component of the movable member in the transducer assembly 100 by increasing the amplitude of the signal output by the piezoelectric disc portion 134 (and the transducer assembly 100 in general).

[0030] The transducer assembly 100 may further include an electromagnetic field (EMF) shield 118 disposed on the housing inner surface 108 to electromagnetically separate the interior portion 106 from the exterior portion 104 of the transducer assembly 100 and the interior portion 106. The EMF shield may include and / or be constructed of a conductive or magnetic material that electrically isolates the printed circuit board (PCB) 120, the connecting wires 122, 124, and 126, and the piezoelectric disk portion 134 from radio frequency electromagnetic radiation. For example, the EMF shield 118 may be constructed of a metal plate, metal foil, metallic ink, a magnetic material, or another suitable material.

[0031] In some cases, the housing 102 and the EMG shield 118 can be integrated into a single unit, wherein the EMF shield 118 is overmolded as an insert during the injection molding operation. In other cases, the EMG shield 118 can be adhered to the housing inner surface 108 using a fastening device that provides a rigid connection between the EMF shield 118 and the housing 102. Alternatively, the EMF shield 118 and the housing 102 can be integrated into the same component, such that the EMF shield 118 is an added component (e.g., a magnetic or metallic powder, etc.) of the thermoplastic used to mold the housing 102. The EMG shield 118 can reduce and / or substantially eliminate the coupling of radio waves, electromagnetic fields, and / or electrostatic fields to the signal output of the PCB 120.

[0032] The printed circuit board (PCB) 120 of the transducer assembly 100 can be configured to include one or more signal conditioning circuits that remove signal content that may interfere with output processing. The one or more signal conditioning circuits can also be configured to amplify the signal output voltage for transmission to a vehicle computer, etc. Figure 5 Exemplary circuitry for PCB 120 is discussed.

[0033] exist Figure 1 Various configurations for placement of PCB 120 are discussed in detail through Figure 4, which can provide various benefits, including simplified assembly, reduced costs, and extended life of the device in the field. For example, Figure 1 A PCB 120 is depicted, which is disposed on the inner portion 106 side of the EMF shield 118. Figure 2 In FIG, PCB 220 is shown as being disposed on the top surface of piezoelectric disc portion 234 (instead of an adjustable mass, where PCB 220 is weighted depending on the specific application so as to also function as an adjustable mass). Figure 3 4 , PCB 320 may be insert molded into EMF shielding layer 418, where EMF shielding layer 418 is a separate layer rigidly disposed in connection with housing 402.

[0034] Although respectively Figure 2 、 Figure 3 4, but it should be understood that in all examples, the PCB can be arranged to communicate with the vehicle computer, etc., via the wiring harness 130, etc., such as Figure 1As depicted. For example, the wiring harness 130 can be connected to a car computer. In some cases, the wiring harness 130 can include and / or can be a male two-pin connector without a pigtail to prevent the wiring from becoming loose from the pigtail, which can vibrate relative to adjacent components during vehicle movement. Mechanical contact can be perceived as structure-borne sound and can overload the output signal transmitted from the transducer assembly 100 via the pigtail. Therefore, the wiring harness 130 can include a wiring harness terminal 128, which is used to removably connect the connector 132 to the car computer and electrically connect the PCB 120 to the car computer. The wiring harness terminal 128 can be connected to the PCB 120 via a connecting wire 126. The PCB 120 can receive sensor data from the piezoelectric disc assembly 133 via connecting wires 122 and 124.

[0035] The transducer assembly 100 is configured such that the annular gasket 112 forms an air gap 144 between the piezoelectric disc assembly 133 and the resonant surface 116. The annular gasket 112 can be a generally cylindrical spacer that can be constructed of a rigid material with relatively low damping properties, such as, for example, a rigid polymer, a rigid polymer with fibers, glass or other additives, a metal, or other suitable material, that allows efficient vibration transfer from the resonant surface 116 to the piezoelectric disc assembly 133. Using a softer material for the annular gasket 112 can attenuate structure-borne vibration signals and reduce electrical output and increase noise. The annular gasket can space the assembly housing 102 and the flexible diaphragm 136 from a mounting surface (e.g., automotive glass, represented by the resonant surface 116) by forming an air gap between the glass (e.g., the resonant surface 116) and the piezoelectric disc portion 134.

[0036] Flexible diaphragm 136 can be constructed of an elastically deformable material, such as, for example, copper, a nickel alloy, or another suitable material. In one aspect, the various components of piezoelectric disc assembly 133 can be commercially available devices, such as piezoelectric diaphragms, which are commercially used as sound output devices for electronic devices, such as clocks, calculators, digital cameras, alarm systems, and the like. For example, flexible diaphragm 136, piezoelectric disc portion 134, and connecting wires 122 and 124 can be commercially available, inexpensive piezoelectric diaphragm sound devices, which are commonly used for sound generation in electronic devices.

[0037] The piezoelectric disc assembly 133 can be disposed above the resonant surface 116 with an air gap 144 separating the diaphragm from the resonant surface 116. By mounting the piezoelectric disc assembly 133 to the annular gasket 112 at the rigidly connected annular edge 140, the rigidly connected surface 142 can form a portion of the closed air gap 144, which increases the sensitivity of the piezoelectric disc portion 134 when it responds to dynamic input (e.g., vibrations with sound) that resonates through the resonant surface 116.

[0038] In some cases, the piezoelectric disc assembly 133 may include a commercially available piezoelectric acoustic component that is rigidly secured to the annular gasket 112 by a fastening means such as, for example, a double-sided adhesive layer, epoxy, or a mechanical connection formed by a press fit between the rigid connecting surface 142 and the annular bottom edge of the EMF shielding layer 118.

[0039] Annular gasket 112 can be separate from housing 102. That is, annular gasket 112 can be connected to housing 102 using snap-fit features that rigidly secure annular gasket 112 to housing 102, such that piezoelectric disc assembly 133 is sandwiched between the two mating components. Other means for connection are possible and contemplated. Regardless of the method of connecting annular gasket 112, housing 102, and piezoelectric disc assembly 133, it should be understood that the connection means can provide a rigid connection surface 142 at the outer edge of the periphery of flexible diaphragm 136, so that diaphragm 136 is away from the mounting surface of resonant surface 116. These features can form a secure connection for transmitting vibration signals to piezoelectric disc portion 134, wherein sensitivity is enhanced by the air pressure differential associated with the vibrations acting across air gap 144. In some cases, the housing and gasket can be a single, integral component.

[0040] Adhesive layer 114 and rigid connection surface 142 (which may also be an adhesive layer) may provide a rigid connection between flexible diaphragm 136, annular gasket 112, and resonant surface 116. Adhesive layer 114 (and in some embodiments, rigid connection surface 142) may include fastening means such as, for example, commercially known permanent double-sided adhesive materials, epoxy bonds, fasteners (e.g., screws / bolts), or another means for providing a rigid connection between flexible diaphragm 136, annular gasket 112, and resonant surface 116.

[0041] The bottom portion of the transducer assembly 100 can be mounted to a resonant surface 116 (which, in some embodiments, can be a car window glass). It will be appreciated that the sensitivity and lifespan of the transducer assembly 100 can be enhanced by corresponding shapes or indentations in the resonant surface 116, such that a cup-shaped disc within the glass surface provides a receiving surface onto which the transducer assembly 100 can be mounted. For example, the mounting surface can be shaped as a flat circular ring or annulus.

[0042] The PCB 120 can provide bandpass filtering via one or more bypass filters and signal amplification via one or more amplifier circuits that can filter the signal output and enhance desired frequencies centered around human speech (e.g., approximately 150 Hz to approximately 8 kHz). The PCB 120 can also provide high-pass filtering that can reduce the effects of any rigid body motion or vibration associated with vehicle motion by reducing the dynamic range of structure-borne signals. The PCB 120 can include one or more operational amplifiers that increase the voltage output of the transducer assembly 100, which is powered by a virtual voltage charge (similar to those used on conventional ECM microphone circuits), which can increase signal strength before it travels down through the wiring harness 130 to an automatic voice recognition system associated with the vehicle's computer.

[0043] The wiring harness 130 can be integrated with the housing 102 such that the wiring harness and housing 102 are molded as a single unit with insert-molded wiring harness terminals 128 for wired connection to the PCB 120. In another example, the PCB 120 can be connected to the wiring harness 130 and the wiring harness terminals 128 via connecting wires 126 that extend through openings in the housing 102 to allow the wires to pass through to the exterior surface 110 and connect with the wiring harness terminals 128. In such cases, the wiring harness 130 can be a separate component that is rigidly fastened to the exterior surface 110 of the housing 102 using a fastening means such as an adhesive, plastic welding, mechanical fasteners, or other suitable means.

[0044] The connector 132 can provide a connection between the PCB 120 and the vehicle computer. In some cases, the piezoelectric diaphragm transducer assembly 100 can be configured to have a low profile and a small package size so that it can be discretely packaged at the edge of a vehicle window glass, behind the vehicle's door trim, or in another area so that the transducer is completely out of the customer's view. The package can have a low profile (e.g., no more than 20 mm high) and can be configured to include sufficient clearance between the outer surface 110 of the transducer assembly 100 and any adjacent components of the vehicle. An exemplary clearance can be, for example, at least 5 mm to 10 mm from any surrounding door trim or other components when mounted to provide adequate protection from vibration signal noise and protection from unintended structure-borne noise that could contaminate the window microphone signal.

[0045] Figure 2 Another exemplary piezoelectric diaphragm transducer 200 is depicted attached to the resonant surface 116. Unless otherwise expressly described in the following paragraphs, the transducer assembly 200 may be used with, for example, Figure 1 The transducer assemblies 100 shown are substantially similar or identical. Figure 2 The transducer assembly 200 shown is Figure 1 The difference of the assembly 100 may be that the piezoelectric disc assembly 233 may be composed of a piezoelectric disc portion 234, a flexible diaphragm 236 and a PCB 220, wherein the piezoelectric disc portion 234 and the PCB 220 are rigidly connected to the top surface of the flexible diaphragm 236. The flexible diaphragm 236 may be connected to the top surface of the flexible diaphragm 236. Figure 1 The flexible diaphragm 136 described above is substantially similar or identical to the piezoelectric disc portion 234. Figure 1 The piezoelectric disc portions 134 are substantially similar or identical.

[0046] The transducer assembly 200 can configure the PCB 220 to additionally function as an adjustable mass (wherein, in addition to the signal conditioning unit, the PCB 220 is weighted to function as a mass and the like is omitted). Figure 1 In one aspect, the PCB 220 can be made heavier by changing its size, thickness, material, or other characteristics so that when disposed within the piezoelectric disc assembly 233, the PCB package size mimics the dimensions of the piezoelectric disc assembly 233. Figure 1 The size and mass distribution of the adjustable mass block. Therefore, the PCB 220 can be disposed on the piezoelectric disc portion 234 and rigidly connected to the piezoelectric disc portion. The connecting wires 222 and 224 can connect the PCB 220 to the piezoelectric disc portion 234 and the flexible diaphragm 236, respectively.

[0047] Figure 2The configuration depicted in FIG200 may provide several advantages, including reducing the number of components in transducer assembly 200, which may reduce manufacturing costs, simplify design complexity, and extend component life and functional reliability. Among other aspects, by integrating the PCB and the tunable mass into a single unit that moves with the piezoelectric disk assembly 233, transducer assembly 200 may experience reduced signal noise from external vibrations because the PCB is separated from the housing by means other than through the flexible diaphragm 236.

[0048] Figure 3 Another exemplary piezoelectric diaphragm transducer device (hereinafter referred to as "transducer assembly 300") is depicted attached to resonant surface 116. Unless otherwise expressly described in the following paragraphs, transducer assembly 300 may be used with, for example, Figure 1 The transducer assemblies 100 shown are substantially similar or identical. Figure 3 The transducer assembly 300 shown is Figure 1 The assembly 100 may differ in that the piezoelectric disc assembly 333 may include a piezoelectric disc portion 334, a flexible diaphragm 336, and an adjustable mass 338. Figure 3 In an exemplary embodiment of the present invention, the PCB 320 may be included as an integral part of the housing 302. Figure 3 , an EMF shielding layer 318 is depicted. The EMF shielding layer 318 can be separate from (and rigidly connected to) the assembly housing 302, or alternatively, can be integrated with the housing 302 such that the EMF shielding layer 318 is provided as a property of a molded addition rather than as a separate component distinct from the housing 302. In this example, the housing 302 can be constructed of a thermoplastic having electromagnetic shielding properties.

[0049] On the other hand, PCB 320 can be sandwiched between EMF shielding layer 318 and housing 302. This exemplary configuration can provide EMF shielding properties that protect PCB 320 from EMF external vibrations originating from the outer surface side of transducer assembly 300, and can also protect PCB 320 from EMF originating from the inner portion 306 side of transducer assembly 300. For example, EMF vibrations can originate from the interior of the vehicle through resonant surface 116 (which can be glass).

[0050] The flexible membrane 336 can be connected to Figure 1 The flexible diaphragm 136 described above is substantially similar or identical to the piezoelectric disc portion 334. Figure 1 The piezoelectric disc portions 134 are substantially similar or identical.

[0051] Figure 3The configuration depicted in FIG300 can provide several advantages, including reducing the number of moving parts in the assembly (which can reduce unwanted signal content caused by the movement of the parts). Other possible advantages can include reduced manufacturing costs associated with eliminating design complexity and extended component life in the field. In other aspects, by integrating the PCB into the housing 302, the transducer assembly 300 can further enhance signal sensitivity and reduce signal noise from vibration because the PCB is integrated with the housing 302 without the need for a connection device and without the possibility of micro-motion associated with physical connection of separate components.

[0052] Figure 4A Another exemplary piezoelectric diaphragm transducer device (hereinafter referred to as "transducer assembly 400") is depicted, wherein the transducer assembly 400 includes a PCB 420 integrated within the electrical shielding wall of an EMF shield 418. Unless otherwise expressly described in the following paragraphs, the transducer assembly 400 may be used with, for example, Figure 1 The transducer assemblies 100 shown are substantially similar or identical. Figure 4A The transducer assembly 400 shown is Figure 1 The assembly 100 may differ in that the piezoelectric disc assembly 433 may include a piezoelectric disc portion 434 , a flexible diaphragm 436 , and an adjustable mass 438 .

[0053] The flexible membrane 436 can be connected to Figure 1 The flexible diaphragm 136 described above is substantially similar or identical to the piezoelectric disc portion 434. Figure 1 The piezoelectric disc portions 134 are substantially similar or identical.

[0054] In one aspect, the PCB 420 and the EMF shield 418 can be insert molded together, and the EMF shield 418 can be rigidly disposed in connection with the housing 402 .

[0055] Figure 4A The configuration depicted in FIG4 can provide several advantages, including reducing the number of connected components in the assembly, which can reduce manufacturing costs and design complexity. Fewer connected components can also extend component life and improve functional reliability. Among other aspects, by integrating PCB 420 with housing 402 and / or EMF shield 418, transducer assembly 400 can enhance signal sensitivity and achieve signal-to-noise reduction in vibrations because the PCB is integrated with housing 402 and / or shield 418 without the need for a connection device and without the possibility of micro-motion associated with physical connection of separate components.

[0056] Figure 4BAnother exemplary piezoelectric diaphragm transducer device (hereinafter referred to as "transducer assembly 401") is depicted in which a housing 403 is provided that is rigidly connected to a separate annular ring 412 such that a flexible diaphragm 436 is rigidly sandwiched between the two connections. Although transducer assembly 401 is depicted with its PCB 420 integrated within the electrically shielding wall of an EMF shield 418, it is also possible to Figure 4B The two-piece housing and annular ring configuration is applied to Figures 1 to 4A Any of the configurations described.

[0057] Unless otherwise expressly described in the following paragraphs, the transducer assembly 400 may be used with Figure 1 The transducer assemblies 100 shown are substantially similar or identical. Figure 4B The transducer assembly 401 shown is Figure 1 The assembly 100 may differ in that the housing 403 is configured to be rigidly connected to the annular ring 412 by a fastening device, which may be a separate component from the housing 403, and the fastening device may be, for example, a snap fit with an undercut snap feature, a press fit, an adhesive bond, a fastener (e.g., a screw / bolt), or another fastening device.

[0058] Figure 4B The configuration depicted in can provide several advantages, including ease of assembly of the transducer assembly 401, which can reduce manufacturing costs and can reduce design complexity. In other aspects, a conventional piezoelectric diaphragm can be converted from a sound output device to an input device as described herein by rigidly connecting the housing 403 and the annular gasket 412 as two separate pieces with the flexible diaphragm 436 rigidly sandwiched between the components.

[0059] Figure 5 Schematically depicts the Figures 1 to 4B PCB circuit 500 for use with any of the devices depicted in

[0045] PCB circuit 500 may include disc element circuit 505 and preamplifier circuit 510. In one example, circuit 500 may include preamplifier circuit and bandpass filter. The bandpass filter may provide an output signal having content between 150 Hz and 8 kHz, and may omit other signal content. The operational amplifier may increase the output voltage so that circuit 500 may provide a signal with an amplitude sufficient to support a clear and unambiguous output that can be used for speech recognition to microphone input circuit 515.

[0060] Figure 6 is a top view of the flexible diaphragm 136 Figure 6-6 (like Figure 1 As shown by arrow 6-6 in the figure. Figure 6-6A rigid connection surface is depicted disposed around the peripheral edge of the diaphragm 136, which mates with a rigidly connected annular edge 140. By connecting the flexible diaphragm 136 only at the edges with a fixed connection that actively transmits vibrations to the flexible diaphragm 136, the connection footprint leaves sufficient internal space to allow the flexible diaphragm 136 to flex due to air pressure differentials created by the micro-vibrations across the resonant surface 116.

[0061] Figure 11A and Figure 11B A piezoelectric diaphragm transducer device 600 is depicted in accordance with an exemplary embodiment of the present disclosure. Unless otherwise expressly described in the following paragraphs, the transducer assembly 600 may be used with, for example, Figure 1 The transducer assembly 100 shown is substantially similar or identical. Figure 11A and Figure 11B In the illustrated transducer assembly 600, the housing 102 can be connected to the annular gasket 112 via the attachment assembly 602. In some cases, the attachment assembly 602 may not require an adhesive to hold the piezoelectric disk assembly 133 between the housing 102 and the annular gasket 112. The adhesive can cause damping and mitigate the transmission of vibrations from the glass to the piezoelectric disk assembly 133. Thus, the lack of adhesive can provide a technical advantage that improves the functionality and accuracy of the piezoelectric diaphragm transducer device 600.

[0062] The annular gasket 112 may include a slot 604. In some cases, the slot 604 may be annular. For example, the slot 604 may extend around the circumference of the annular base 112. The slot 604 may have any suitable size, shape, or configuration. The slot 604 may include a lug 606 and a wall 608. In some cases, the lug 606 and the wall 608 may be transverse to each other. The lug 606 and the wall 608 may have any suitable size, shape, or configuration. One or more protrusions 610 may extend from the wall 608. The protrusions 610 may have any suitable size, shape, or configuration.

[0063] The housing 102 may include a groove 612. In some cases, the groove 612 may be annular. For example, the groove 612 may extend around the inner circumference of the housing 102. The groove 612 may have any suitable size, shape, or configuration. The groove 612 may include a lug 614 and a wall 616. In some cases, the lug 614 and the wall 616 may be transverse to each other. The lug 614 and the wall 616 may have any suitable size, shape, or configuration. One or more channels 618 may be disposed within the wall 616. The channel 618 may include an open end 620 and a closed end 622. In some cases, the channel 618 may include a first portion 624 and a second portion 626 extending across the first portion 624. That is, the channel 618 may be L-shaped, etc. The channel 618 may have any suitable size, shape, or configuration.

[0064] The slot 604 of the annular gasket 112 and the groove 612 of the housing 102 can be configured to mate with each other. That is, the slot 604 and the groove 612 can be complementary to each other. In this way, the protrusion 610 can be configured to mate with the channel 618. For example, the protrusion 610 can enter the channel 618 through the open end 620 of the channel 618 and move along the first portion 624 of the channel 618 when the housing 102 is pressed against the annular gasket 112. Next, when the housing 102 is rotated, the protrusion 610 can travel along the second portion 626 of the channel 618. In some cases, the second portion 626 of the channel 618 can be angled (e.g., slightly tilted) so that when the housing 102 is rotated onto the annular gasket 112, the housing 102 is tightened against the annular gasket 112. For example, the second portion 626 of the channel 618 can be angled away from the annular gasket 112. In this manner, the protrusion 610 may travel along the second portion 626 of the channel 618 , which may cause the protrusion 610 to exert increasing force on the second portion 626 of the channel 618 as the protrusion 610 travels further upward and into the second portion 626 of the channel 618 .

[0065] The piezoelectric disc assembly 133 can be disposed between the housing 102 and the annular gasket 112. For example, the outer edge 628 of the piezoelectric disc assembly 133 can be sandwiched (i.e., captured) between the lug 606 of the annular gasket 112 and the lug 614 of the housing 102. In this manner, the piezoelectric disc assembly 133 can be secured in place without the use of adhesives.

[0066] Figure 7 A schematic diagram of an exemplary vehicle control system 700 is depicted that is configured to receive an acoustic input signal from a transducer assembly 745. The transducer assembly 745 may be configured as described with respect to a corresponding Figures 1 to 4BAny of the transducer assemblies 100, 200, 300, or 400 described herein are substantially similar or identical. Although described below as an autonomous vehicle, the control system 700 can be configured for use in a vehicle 705, which can be an autonomous vehicle, a semi-autonomous vehicle, or a conventionally driven vehicle. The control system 700 can include a user interface 710, a navigation system 715, a communication interface 720, an autonomous driving sensor 730, an autonomous mode controller 735, and one or more processing devices 740. The control system 700 can also include a speech recognition system 755. The transducer assembly 745 can provide an input signal to the speech recognition system 755, which can be configured to interpret the input signal as a contextualized speech input. In one embodiment, the control system 700 can perform one or more vehicle actions based on the input, such as starting a drive motor, stopping the vehicle, performing steering or braking actions, or other vehicle operations.

[0067] The user interface 710 can be configured or programmed to present information to a user during operation of the vehicle 705. In one aspect, the user interface can provide an audible output of signals received from the transducer assembly 745. In addition, the user interface 710 can be configured or programmed to receive user input and, therefore, can be located in or on the vehicle 705 so that it is visible, audible, or interactive to a passenger or operator. For example, in an embodiment where the vehicle 705 is a passenger car, the user interface 710 can be located in the passenger compartment.

[0068] The navigation system 715 can be configured and / or programmed to determine the location of the autonomous vehicle 705. The navigation system 715 can include a global positioning system (GPS) receiver that is configured or programmed to triangulate the position of the AV 705 relative to satellites or land-based transmitter towers. Thus, the navigation system 715 can be configured or programmed for wireless communication. The navigation system 715 can further be configured or programmed to develop a route from the current location to a selected destination and display a map and present driving directions to the selected destination via, for example, the user interface 710. In some cases, the navigation system 715 can develop a route based on user preferences. Examples of user preferences can include maximizing fuel efficiency, reducing travel time, traveling the shortest distance, etc.

[0069] In one aspect, the vehicle control system 700 can be configured to receive audio data from a piezoelectric diaphragm transducer 750 (hereinafter referred to as "transducer 750") and perform one or more vehicle operations based on the audio data. For example, the vehicle control system 700 (hereinafter referred to as "control system 700") can receive audio data, wherein the data includes one or more engine or motor sounds indicating a vehicle maintenance issue requiring immediate attention or repair. Thus, the control system 700 can receive the audio data, compare the audio data to a database of audio sounds associated with vehicle maintenance indications, and determine that the vehicle requires immediate maintenance based on a match between the audio data and the maintenance indication. In response to determining that the vehicle requires immediate maintenance, the control system 700 can control the autonomous mode controller 735 to navigate to a maintenance location or other safe location so that the maintenance issue can be resolved. In one aspect, the control system 700 can obtain information from the navigation system 715 and navigate the vehicle 705 to the maintenance location based on GPS information.

[0070] On the other hand, the speech recognition system 755 can receive the audio data and determine that the audio indicates human speech. The control system 700 can cause the speech recognition system 755 to recognize speech content in the audio data and evaluate the speech content for context indicating that an immediate vehicle control action is required (such as stopping the vehicle, slowing the vehicle, steering the vehicle to the side of the road, etc.).

[0071] Control system 700 can facilitate communication between the driver of vehicle 705 and another driver. For example, another vehicle may be parked next to vehicle 705, and the driver of the other vehicle may initiate a temporary communication. The driver of the second vehicle may attempt to attract the attention of the driver of vehicle 705 by asking for help, hoping that their voice can be heard through the closed windows of vehicle 705. Although the driver may not normally be able to hear the communication issued by the second driver when the windows are closed, music is playing, etc., the voice recognition system 755 can receive the voice input (sound) through transducer 750, which can be attached to the car window 760 of vehicle 705, and determine via voice recognition system 755 that the voice content of the sound received from transducer 750 is relevant to the need to play an audio feed through the audio system of vehicle 705. Control system 700 can output the voice signal through communication interface 720 and / or user interface device 710. In this example, although the windows are closed, a clear reproduction of the individual's voice can be emitted through one or more vehicle sound systems, so that the driver of vehicle 705 can clearly hear the question being asked by the other driver.

[0072] In another example, an observer outside the vehicle may notice that the vehicle operator has left an object (e.g., a cup of coffee) on the roof of the vehicle and inadvertently begins driving away with the cup of coffee on the roof. The observer may yell, "Driver! Your coffee is on the roof!" Although the driver may not be able to hear the verbal utterance, the control system 700 may receive the audio data via the transducer 750, interpret the data to contextualize the speech content indicating "coffee is on the roof," compare the context to a database indicating actions associated with particular phrases in the context (e.g., "coffee is on the roof" is associated with the need to slow down and stop the vehicle when it can safely do so), and issue vehicle control commands to the autonomous mode controller 735 based at least in part on the associated actions associated with the phrases contextualized by the speech recognition system.

[0073] The communication interface 720 may be configured or programmed to facilitate wired and / or wireless communication between components of the vehicle 705 and other devices (such as a remote server or another vehicle) when using a vehicle-to-vehicle communication protocol. The communication interface 720 may also be configured and / or programmed to use any number of communication protocols (such as Low power or Wi-Fi) enables the vehicle 705 to communicate directly with the mobile device.

[0074] The telematics transceiver 725 may include wireless transmission and communication hardware that may be configured to communicate with one or more transceivers associated with telecommunications towers and other wireless telecommunications infrastructure. For example, the telematics transceiver 725 may be configured and / or programmed to receive messages from and transmit messages to one or more cellular towers associated with a telecommunications provider and / or a telematics service delivery network (SDN) associated with the vehicle 705. In some examples, the SDN may establish communication with a mobile device, which may be and / or include a cellular phone, tablet computer, laptop computer, key fob, or any other electronic device. An internet-connected device such as a PC, laptop computer, notebook computer, or a Wi-Fi-connected mobile device or another computing device may establish cellular communication with the telematics transceiver 725 via the SDN.

[0075] The communication interface 720 can also communicate using one or more vehicle-to-vehicle communication technologies. Examples of vehicle-to-vehicle communication protocols may include, for example, a dedicated short-range communication (DSRC) protocol. Thus, the communication interface 720 can be configured or programmed to receive messages from a remote server and / or transmit messages to other autonomous, semi-autonomous, or manually driven vehicles. In some aspects, the transducer 750 can generate an acoustic signal using the vehicle-to-vehicle communication protocol, which is transmitted to another vehicle.

[0076] The autonomous driving sensors 730 may include any number of devices configured or programmed to generate signals that assist in navigating the vehicle 705 when the vehicle 705 is operating in an autonomous (e.g., unmanned) mode. Examples of the autonomous driving sensors 730 may include radar sensors, lidar sensors, vision sensors, etc. When the vehicle 705 is operating in an autonomous mode, the autonomous driving sensors 730 may help the vehicle "see" the road and the vehicle's surroundings, and / or navigate around various obstacles.

[0077] The autonomous mode controller 735 can be configured or programmed to control one or more vehicle subsystems when the vehicle is operating in autonomous mode. Examples of subsystems that can be controlled by the autonomous mode controller 735 may include one or more systems for controlling braking, ignition, steering, acceleration, transmission control, and / or other control mechanisms. The autonomous mode controller 735 can control the subsystems based at least in part on signals generated by the autonomous driving sensors 730. It is contemplated that the control system 700 can use information received from the transducer 750 to control one or more subsystems. Exemplary information can include voice data as described above, vehicle sounds indicating mechanical failure or need for maintenance, emergency situations indicated by sounds emitted by, for example, emergency vehicle sirens, and other auditory inputs.

[0078] Figure 8A and Figure 8B A front view of the rearview mirror 805 and a partial cross-sectional view of the rearview mirror 805 are depicted, respectively. The rearview mirror 805 is configured with a piezoelectric diaphragm transducer 810 (hereinafter referred to as "transducer assembly 810"), which can receive vibration input from the rearview mirror glass 820 of the rearview mirror 805 and generate an acoustic signal that can be used for various purposes. The transducer assembly 810 can be used with the following devices: Figure 1 The depicted transducer assemblies 100 are substantially similar or identical.

[0079] like Figure 8B The cross-sectional view AA shown in FIG depicts a transducer assembly 810 on an interior portion 815 of a rearview mirror 805. The transducer assembly 810 is depicted as being rigidly connected to an interior surface 825 of the rearview mirror glass 820. In an exemplary embodiment, the transducer assembly 810 can be used as a sound input device to generate sound on an interior surface of a vehicle (e.g., on a surface similar to that shown in FIG). Figure 7 705) so that the transducer 810 can capture sound input through the glass 820 and transmit the sound input to a connected vehicle computer. Figure 8A and Figure 8BThe illustrated configuration may replace or supplement interior microphones typically disposed within the interior of a vehicle cabin (eg, where the microphone is integrated with a rearview mirror, sun visor, or at another interior location).

[0080] In some aspects, the transducer assembly 810 can be mounted on other non-glass surfaces of the vehicle. For example, Figure 9 A vehicle 905 is depicted having exemplary transducer assemblies 910, 915, 920, 925, 930, and 935 rigidly adhered to various vehicle surfaces that provide various corresponding benefits as resonant surfaces. The transducer assemblies 910 through 935 may be connected and arranged to communicate with a vehicle control system 940 via a control bus 945. The control system 945 may communicate with respect to Figure 7 The control system 700 described is substantially similar or identical.

[0081] In some aspects, the vehicle control system 940 can be coupled to a transducer assembly 910, which can be rigidly coupled to the exterior surface of the vehicle windshield 950 beneath the window frame 955. One advantage of placing the transducer assembly at a location behind the upper windshield frame can include utilizing the large area of a resonant surface (e.g., windshield 950), which can produce a high-quality sound signal originating from a forward position relative to the vehicle 905. Thus, sound can resonate through the windshield, and the transducer assembly 910 can generate an output signal through the resonance.

[0082] The control system 905 may be placed in electrical communication with a transducer assembly 925 disposed on a rearview mirror of the vehicle 905, which may provide a means for pickup of sound originating from the sides or rear of the vehicle 905. Additionally, voice communications from individuals standing outside the vehicle 905 may generally be flush with the transducer assemblies 910, 925, 930, 935, etc., making speech readily received by the resonant surface and the transducer assembly attached thereto.

[0083] Figure 10A cross-sectional view of an exemplary configuration for attaching a transducer assembly 1015 to the outer surface of an automotive glass 1005 below a glass bezel 1025 is shown. The automotive glass 1005 may include an indexing recess 1010 that forms a pocket for mounting the transducer assembly 1015. The indexing recess 1010 may provide a gap (e.g., gap 1020) between the surface of the transducer assembly 1015 and any other vehicle components adjacent to the assembly, such as, for example, the glass bezel 1025. Creating a gap may mean that components adjacent to the transducer assembly 1015 do not contact the transducer assembly 1015. By providing the recess 1010 in the automotive glass 1005, the transducer assembly 1015 may be mounted in a location on the vehicle that may be out of the user's view and may protect the transducer assembly 1015 from physical damage caused by weather or collisions, etc. However, it should be understood that among the many advantages of the embodiments described herein, transducer assembly 1015 (and other similar transducer assemblies described herein) can be used as robust and weather-resistant microphones that can be mounted on exterior surfaces of vehicles because they are generally unaffected by weather, dirt, etc.

[0084] In the above disclosure, reference has been made to the accompanying drawings which form a part of the above disclosure, which illustrate specific embodiments in which the present disclosure may be practiced. It will be understood that other embodiments may be utilized and structural changes may be made without departing from the scope of the present disclosure. References in the specification to "one embodiment," "an embodiment," "an exemplary embodiment," etc. indicate that the embodiment being described may include a particular feature, structure, or characteristic, but every embodiment may not necessarily include the particular feature, structure, or characteristic. Furthermore, such phrases do not necessarily refer to the same embodiment. Furthermore, when a feature, structure, or characteristic is described in conjunction with an embodiment, whether or not explicitly described, those skilled in the art will recognize such feature, structure, or characteristic in conjunction with other embodiments.

[0085] It should also be understood that the word "example" as used herein is intended to be non-exclusive and non-limiting in nature. More specifically, the word "exemplary" as used herein indicates one of several examples, and it should be understood that no undue emphasis or focus is placed on the particular example being described.

[0086] Computer-readable media (also referred to as processor-readable media) include any non-transitory (e.g., tangible) media that participate in providing data (e.g., instructions) that can be read by a computer (e.g., by a processor of a computer). Such media can take many forms, including but not limited to non-volatile media and volatile media. A computing device may include computer-executable instructions, where the instructions can be executed by one or more computing devices (such as those listed above) and stored on a computer-readable medium.

[0087] With respect to the processes, systems, methods, heuristics, and the like described herein, it should be understood that although the steps of such processes, etc. have been described as occurring in a certain ordered sequence, such processes can be practiced with the steps performed in an order other than that described herein. It should also be understood that certain steps can be performed simultaneously, other steps can be added, or certain steps described herein can be omitted. In other words, the descriptions of the processes herein are provided for the purpose of illustrating various embodiments and should in no way be construed as limiting the claims.

[0088] Therefore, it should be understood that the above description is intended to be illustrative and not restrictive. Upon reading the above description, many embodiments and applications other than the examples provided will be apparent. The scope should not be determined with reference to the above description, but rather with reference to the appended claims and the full scope of equivalents to which such claims are entitled. It is anticipated and expected that the technology discussed herein will develop in the future, and that the disclosed systems and methods will be incorporated into such future embodiments. In short, it should be understood that the present application is capable of modification and variation.

[0089] All terms used in the claims are intended to be given their ordinary meaning as understood by those skilled in the art as discussed herein, unless expressly indicated to the contrary in this document. Specifically, unless a claim recites an express limitation to the contrary, the use of singular articles such as "a", "said", "the" and the like should be interpreted as reciting one or more of the elements indicated. Unless otherwise specifically stated or understood otherwise in the context used, conditional language such as "can", "may", "possibly" or "may" is generally intended to convey that certain embodiments may include certain features, elements and / or steps, while other embodiments may not include certain features, elements and / or steps. Therefore, such conditional language is generally not intended to imply that one or more embodiments require each feature, element and / or step in any way.

[0090] According to one embodiment, the printed circuit board includes an amplification circuit and a bandpass filter, wherein the printed circuit board is configured to: receive a signal from the piezoelectric assembly; eliminate unwanted signal content through the bandpass filter; amplify the signal through the amplification circuit; and transmit the signal.

[0091] According to one embodiment, the invention also features a wiring harness terminal in communication with the printed circuit board.

[0092] According to one embodiment, the transducer assembly gasket is annular.

[0093] According to one embodiment, the transducer assembly housing and the gasket are integral.

[0094] According to the present invention, a method includes attaching a transducer assembly to a resonant surface of a vehicle, the transducer assembly including a piezoelectric assembly spaced apart from the resonant surface; receiving, by the piezoelectric assembly, dynamic vibrations resonating from the resonant surface; and generating, by the piezoelectric assembly, an electrical output signal associated with the dynamic vibrations.

Claims

1. A transducer assembly for a vehicle having a resonant surface, the transducer assembly comprising: case; an electromagnetic field shielding layer disposed on an inner surface of the housing and configured to electromagnetically separate an interior portion of the transducer assembly from an exterior portion of the transducer assembly; a gasket connected to the housing; as well as a piezoelectric assembly, the piezoelectric assembly being disposed between the gasket and the housing, The gasket is configured to be connected to the resonant surface to form an air gap between the resonant surface and the piezoelectric assembly.

2. The transducer assembly of claim 1, wherein the piezoelectric assembly comprises a diaphragm.

3. The transducer assembly of claim 2, wherein the piezoelectric assembly comprises a piezoelectric disk disposed on the diaphragm.

4. The transducer assembly of claim 3, wherein the piezoelectric assembly comprises an adjustable mass disposed on the piezoelectric disk.

5. The transducer assembly of claim 1, wherein the piezoelectric assembly is configured to receive dynamic vibrations resonating from the resonant surface.

6. The transducer assembly of claim 5, wherein the piezoelectric assembly is configured to generate an electrical output signal associated with the dynamic vibration.

7. The transducer assembly of claim 1, further comprising a printed circuit board in communication with the piezoelectric assembly.

8. The transducer assembly of claim 7, further comprising a wiring harness terminal in communication with the printed circuit board.

9. The transducer assembly of claim 1, wherein the gasket is annular.

10. The transducer assembly of claim 1, wherein the gasket is rigidly connected to the resonant surface.

11. The transducer assembly of claim 1 , wherein the housing and the gasket are integral.

12. A transducer assembly for a resonant surface, the transducer assembly comprising: a housing having an inner portion and an outer portion; an electromagnetic field shielding layer disposed on an inner surface of the housing and configured to electromagnetically separate the inner portion from the outer portion; a gasket having a proximal end and a distal end, wherein the proximal end is configured to be connected to the housing and the distal end is configured to be connected to the resonant surface; a piezoelectric assembly disposed between the gasket and the housing, wherein the piezoelectric assembly is configured to be attached around the proximal end of the gasket and spaced apart from the resonant surface; as well as An air gap is formed by the gasket, the piezoelectric assembly, and the resonant surface. 13 . The transducer assembly according to claim 12 , wherein the piezoelectric assembly comprises a diaphragm, a piezoelectric disk disposed on the diaphragm, and an adjustable mass disposed on the piezoelectric disk.

14. The transducer assembly of claim 12, further comprising a printed circuit board in communication with the piezoelectric assembly.

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