MATERIAL STRUCTURES

CROSS-REFERENCED APPLICATIONS

[0001] This application claims priority to U.S. Provisional application number 62/872,539 filed on July 10, 2019 the disclosure of which is included herein by reference in its entirety.

FIELD OF THE INVENTION

[0002] This invention generally is directed to materials that are capable of selectively self-adapting to and damping high amplitude sounds. More specifically, the invention is directed to systems and methods for producing noise-damping structures.

BACKGROUND

[0003] The concept of sound management is not new. There have been many developments in the area of sound management including noise cancellation headphones, soundproof walls, and“quiet” technology found in a variety of applications. For example, the music industry utilizes different sound reduction techniques for recording music as well as reducing sound levels that may reach a person’s ear. Other industries that apply sound management techniques and/or devices can include, industrial applications, commercial and/or consumer products as well as military applications, to name a few. Many such applications can use a variety of materials alone or in combination with advancements in electrical technology to improve and/or reduce sound. Many such applications can be specifically designed to protect the delicate components of the human ear.

[0004] Military applications, for example, have drawn a great deal of interest in recent years because the type of weapons and/or equipment used for military purposes have changed in many ways. For example, many of the vehicle systems can have noise levels ranging from 87 to nearly 120 decibels. Additionally, many of the weapon systems have noise levels ranging from 152 to 190 or more decibels. Furthermore, soldiers are often exposed to explosive devices in a battlefield environment that can produce both percussive effects as well as high amplitude sound waves. Accordingly, recurring exposure to such sound levels can be cause permanent damage to the human ear. Therefore, hearing protection methods and/or devices are regularly encouraged.

[0005]

[0006] Although many people use some type of device to protect their hearing, current technologies fail to be adaptable to the variety of situations in which they are used. Additionally, many devices can be too bulky and/or uncomfortable to use and thus, many people will opt to not use hearing protection. Furthermore, many current devices do not allow individuals to have conversations at normal sound levels because the device tends to block out such sound levels. Therefore, current manufactures fail to take advantage of improved technology to produce devices that are user friendly as well as protective.

SUMMARY OF THE INVENTION

[0007] Many embodiments are directed to micro-architected structures that are capable of adapting or responding to a force such that the adaptation can result in a reduction of the amplitude of the force in a downstream environment.

[0008] Various embodiments are directed to a self-tuning micro-architected structure that has a baseplate structure with a first face and a second face and at least one orifice passing through the faceplate. The micro-architected structure can also have at least one tuning plate, connected to the baseplate by a resilient connection, where the tuning plate is configured to resiliently respond to a received sound pressure wave such that the tuning plate moves and wherein the movement of the tuning plate results in an engaged position and a disengaged position. The engaged position results in a constriction of the at least one orifice in the baseplate. The disengaged position results in an opening of the at least one orifice in the baseplate.

[0009] In other embodiments, the at least one tuning plate is a circular disc having an upper face and a lower face and an opening extending between the upper and lower faces and wherein the opening is aligned with the at least one orifice. [0010] In still other embodiments, the resilient connection is a plurality of resilient connectors disposed between the circular disc and the baseplate at an angle such that the movement of the tuning plate is rotational as well as directional to towards the base plate wherein the plurality of resilient connectors close on each other in a manner to constrict the orifice.

[0011] In yet other embodiments, the tuning plate further comprises a stem element extending from a bottom face of the tuning plate towards the baseplate, and wherein the stem element is connected to at least two knee elements disposed laterally, each on a aside of the stem element and wherein the movement of the tuning plate is translated to each of the at least two knee elements through the resilient connection such that a perpendicular movement of the tuning plate generates a lateral movement of the knee elements so as to constrict the at least one orifice.

[0012] In still yet other embodiments, the micro-architected structure has a plurality of tuning plates each with at least two knee elements and wherein the knee elements of one of the plurality of tuning plates are configured to move towards at least another knee element of at least one other tuning plate.

[0013] In other embodiments, the base plate is a moveably interconnected lattice structure.

[0014] In still other embodiments, the baseplate is configured to be acted upon by a pulling force such that the pulling force results in the tuning plate being in the disengaged position such that the disengaged position generates a stored energy in the micro- architected structure.

[0015] In yet other embodiments, the tuning plate is a plunger element having an upper plate and a stem disposed on a bottom face of the upper plate and wherein the stem is configured with a prong element; wherein the resilient connection is a plurality of support elements resiliently connected to the plunger element and movably connected to the baseplate and wherein each of the support elements has a connecting face that corresponds with and cooperatively connects with the prong element while in the disengaged position and is spaced from the prong element in the engaged position. [0016] In still yet other embodiments, the micro-architected structure has a plurality of wall elements connected to the support elements such they may move in accordance with the movement of the support elements such that the movement of the wall elements act to constrict the orifices in the engaged position and open the orifices in the disengaged position.

[0017] In other embodiments, the micro-architected structure has a plurality of prong elements extending laterally from the stem element.

[0018] In still other embodiments, the components are made of a plastic material.

[0019] Other embodiments are directed to a sound reduction device that has a structural framework suitable for placement within an ear of a user. The sound reduction device has a tunable micro-architected structure or structures in accordance with the various embodiments described herein.

[0020] Other embodiments are directed to a sound reduction device that incorporates one or more embodiments of the micro-architected structures in a manner in which to reduce sound in a vehicle or a room.

[0021] Additional embodiments and features are set forth in part in the description that follows, and in part will become apparent to those skilled in the art upon examination of the specification or may be learned by the practice of the disclosure. A further understanding of the nature and advantages of the present disclosure may be realized by reference to the remaining portions of the specification and the drawings, which forms a part of this disclosure.

BRIEF DESCRIPTION OF THE DRAWINGS

[0022] The description will be more fully understood with reference to the following figures, which are presented as exemplary embodiments of the invention and should not be construed as a complete recitation of the scope of the invention, wherein:

[0023] Fig. 1 illustrates an example a hearing protection device in accordance with known art.

[0024] Fig. 2 illustrates a reduction in downstream amplitude of a sound impulse in accordance with embodiments of the invention. [0025] Fig. 3 is a graphical illustration of a reduction in pressure using hearing protection in accordance with embodiments of the invention.

[0026] Fig. 4 is a graphical illustration of a resistance versus velocity data plot in accordance with embodiments of the invention.

[0027] Figs.5A and 5B illustrates a tunable framework in accordance with embodiments of the invention.

[0028] Figs. 6A to 6C illustrates a tunable structure to reduce impulse amplitude in accordance with embodiments of the invention.

[0029] Fig. 6D illustrates a sequence of movement of a tunable structure in accordance with embodiments of the invention.

[0030] Figs. 7A to 7C illustrate a tunable structure in accordance with embodiments of the invention.

[0031] Figs. 7D-7F illustrate a sequence of movement of portions of a tunable structure in accordance with embodiments of the invention.

[0032] Figs. 8A to 8D provide graphical illustrations of the movement comparison between portions of a tunable structure in accordance with embodiments of the invention.

[0033] Figs. 9A and 9B illustrate a tunable element in accordance with embodiments of the invention.

[0034] Figs. 9C and 9D illustrate a matrix of tunable elements in accordance with embodiments of the invention.

[0035] Fig. 9E illustrates a sequence of movement of a tunable structure in accordance with embodiments of the invention.

DETAILED DESCRIPTION OF THE INVENTION

[0036] Turning now to the drawings, many of the embodiments described herein are directed to a tunable noise damping apparatus that can effectively dampen high threshold noises while remaining highly transmissive at lower decibels thresholds. Many embodiments include an architecture material structure that is tunable to be receptive to the input of incoming noise amplitude waves. Many embodiments may include a plurality of interconnected components that can move in relation to each other. The moveably interconnected components can be configured to move in response to a received impulse of sound such that any spaces between the interconnected components are reduced thereby reducing the amplitude of the received impulse. In some embodiments, the moveably interconnected components may be connected to a baseplate structure that can act as a support structure. In some embodiments, the baseplate may be a solid structure. In other embodiments, the base plate can be a resilient lattice structure that may respond to input sounds at various amplitudes causing some or all of the interconnected components to move.

[0037] The development of improved sound management has been a work of great interest for many years. As previously discussed, sound management applications often include those aimed at protecting the delicate parts of the human ear. The military, for example, continues to invest in developments aimed to improve the equipment used by many military personnel. This is due to the increasing number of U.S. Military veterans that are currently receiving compensation for hearing loss, which amounts to over $1 billion annually. Hearing loss is the most common service-connected disability. Accordingly, the military illustrates one example of an increased motive to develop improved systems and methods for sound management.

[0038] Sound waves can create pressure, which can be measured in terms of the amplitude of the wave called decibels. The amplitude of a sound wave tends to decrease over time. However, some situations may create reverberant conditions that create high amplitude impulses over a period, thus posing a greater risk. The larger the amplitude over a longer period can lead to increased damage to the delicate components of the human ear. This is generally a concept that is well understood by the many professions that deal with sound and noise such as the music industry and the military. Accordingly, many such institutions implement sound reduction devices to help reduce the amplitude of the sound waves that enter the ear. Such devices have included earplugs, noise cancelling headsets, passive active noise control devices, and walls with other sound absorbing materials such as foam. Such devices can help to reduce the number and amplitude of sound impulses, but they are not without their limitations that still contribute to hearing loss. [0039] Standard earplugs such as those illustrated in Fig. 1 have been used in various situations. Such earplugs can be effective at reducing high amplitude impulses; however, they dampen all sounds including low amplitude noises, which can hinder communication. As a result, they are often not used consistently at the necessary times (i.e. , a typical user will remove them to conduct normal conversations). For example, a gunner positioned in a gun turret of a military vehicle may not be affected by the sounds of the weapon system or vehicle but may also not be capable of hearing the commands of the truck commander. Likewise, dismounted soldiers may not be able to hear smaller sounds that could make a life-or-death difference.

[0040] Further developments have provided for such things as noise cancelling headsets. Such headsets are typically designed to cancel out undesired sound amplitudes in many numbers of ways only allowing desired low amplitude sounds to proceed to the user. Unfortunately, such noise cancelling headsets tend to be bulky and many require the use of some type of power source to engage the noise cancelling characteristics. Accordingly, such devices tend not to be effective for use in military applications. Additionally, such devices can have

[0041] Other developments have included the use of passive active noise control using layers of foam and Polyvinylidene Difluoride (PVDF) where the foam acts as a passive damping and actuating the piezoelectric PVDF might act as active noise cancellation. Additionally, other developments have led to the use of impedance control to limit the high frequency sounds. However, such developments also require complex configurations that may not be desirable for many situations. Accordingly, a simple design that can be used in easy to use devices would be desirable.

[0042] Non-linear damping earplugs currently exist and can offer a simple solution to reduce the high amplitude noises that are not desired. Non-linear damping operates by producing an acoustic impedance, which is essentially a viscous resistance and a non linear dependence on the particle velocity at its center. Essentially, it operates by placing a“filter” of sorts in the path of the sound with a hole that acts to produce a vortex in the flow thereby reducing the amplitude of the noise. For example, Fig. 2 illustrates a filtering device under the principle of non-linear damping that may be placed within a channel 202 wherein a central orifice 204 is configured to alter the upstream flow such that a vortex or vortices 206 are created in the downstream path 208 of the sound wave. The vortices 206 illustrate a disrupted flow of sound wave and thereby reduce the amplitude of the sound wave to a more reasonable level. Such devices can often result in a higher Noise Reduction Rating (NRR) that may be more desirable for the end user. The EPA uses an NRR to establish the level of hearing protection that a device may offer - the higher the NRR the more the hearing may be protected from higher amplitude sounds. The typical applications of non-linear damping devices tend to only use a single hole or single orifice to create the vortices. Additionally, such devices can still allow potentially damaging sound waves to penetrate the human ear based on the size and configuration of the hole.

[0043] In contrast to previous designs, many embodiments of the invention may incorporate one or more holes to produce the vortex necessary to reduce the amplitude of the upstream sound. For example, some embodiments may utilize a self-sizing or a tunable hole or holes that are capable of responding to the impulse wave from the upstream sound thereby reducing the size of the orifice(s) in relation to the pressure wave from the sound. Fig. 3 illustrates a graphical representation of the sound attenuation of a self-damping or tunable orifice in accordance with many embodiments of the invention. It can be illustrated that upon interaction with a higher amplitude sound having a larger pressure, the attenuation of the device may be significantly more than the attenuation from normal sound conditions. Such embodiments may function in any number of methods using any number of materials that may offer a resilient like response to pressure, specifically the pressure generated from noise.

[0044] Turning now to Fig. 4, a graphical illustration of the acoustical attenuation of an embodiment with more than one orifice. For example, embodiments with dual orifices illustrate an increased resistance of a device with dual orifices over a device with a single orifice. This can be illustrative of various embodiments which can take advantage of more than one orifice by which sound waves can be controlled. In numerous embodiments, the multiple orifices can be used to generate more than one set of vortices and thereby operate to create a greater damping of high amplitude sound waves. As illustrated in Fig. 4, the dual orifice generates a greater amount of damping than a device with a single orifice. Thus, multiple orifices can operate to quickly attenuate high amplitude sound waves.

[0045] Resilient structures, in accordance with many embodiments of the invention may be implemented in any number of ways to achieve high NRR’s as well as self damping. For example, Figs. 5A and 5B illustrate a micro-architected structure 502 that can be formed from a number of individual elements 504. The individual elements 504 may be made up of a number of resiliently connected structural components 506. The geometric shape of such structures may have the ability to respond and reshape under pressure such that the internal spaces 508 between the structural elements 506 may be reduced and/or increased during the application or removal of air pressure. The individual structural elements 506 may be interconnected at one or more hinge points 510 that can allow for some movement in the structure itself. Additionally, many of the structural elements 506 may be engineered or designed to be resilient or flexible such that only an elastic deformation of the element 502 and 504 may occur under pressure. The combination of hinge points 510 and resiliently connected elements 506 can result in a structure that can adapt in a variety of ways to any variety of forces. For example, the structural elements 506 may be interconnected in such a way that together they form a cohesive structure capable of supporting an ambient force such as ambient air pressure. Flowever, upon reception of a force that exceeds the ambient force, the structural elements may move in such a manner that the internal spaces 508 are reduced. It should be understood that Figs. 5A and 5B illustrate an embodiment of a micro-architected structure that can be tunable to respond to any number of sound impulses and does not represent all embodiments.

[0046] The use of resilient structures can be beneficial in many embodiments because they can be adapted such that the closure of spaces is tunable to generate the vortexes necessary to effectively reduce the amplitude of an incoming sound wave to a more desirable level; thus effectively increasing the NRR of the device. Accordingly, many embodiments may incorporate resilient structures or features to generate that self-adjusts to the associated pressure from a noise. The resilient structures, according to many embodiments of the invention, may incorporate other elements such as plates, rings, platforms, etc. that may be connected to or interconnected with other resilient elements. Additionally, some embodiments may incorporate such additional elements that are manufactured of the same or similar resilient material. Accordingly, many embodiments may use a number of manufacturing processes to produce the resilient structures or resilient elements. For example, some embodiments may use 3-D printing techniques to create a filter with multiple holes that incorporates the use of the resilient structural elements. Additionally, some embodiments may use injection molding or casting to create the filters. Likewise, many embodiments may use other materials including, but not limited to, rubber, Teflon, paper, plastic, foam etc.

[0047] Turning now to Fig. 6A an embodiment of a tunable structure 600 that may be used in a variety of applications for noise reduction. Sound protection, in accordance with some embodiments may also utilize the tunable structure 600. In various embodiments, the tunable structure 600 may include a base plate 602 with one or more openings 604. Additionally, many embodiments may include corresponding orifice plates 606 configured with one or more orifices 608 positioned coaxially with the corresponding opening. Each of the orifice plates 606 may be connected to the base plate by one or more resilient support elements 610. The resilient elements 610, in many embodiments, can allow for the orifice plates 606 to move with respect to the base plate 602. In numerous embodiments, the resilient elements 610 may be disposed in such a manner to allow for a rotational movement as well as a perpendicular moment of the orifice plate 606 with respect to the base plate 602. It can be understood that in many such embodiments, a rotational as well as perpendicular movement may act to effectively reduce the size of the opening 604 in the base plate. From the standpoint of noise reduction, the reduction of size of the orifice by which sound is directed will effectively reduce the amplitude of the wave entering the orifice by the introduction of vortices.

[0048] Fig. 6B further illustrates the use of resilient elements 610 to support the orifice plate 606. It can be understood that a number of resilient elements 610 can be positioned in a variety of locations to provide a support as well as allow for movement of the orifice plat 606 with respect to the base plate 602. The resilient elements 610 can be produced in such a manner that they are tuned or responsive to a variety of different amplitudes. For example, in some embodiments the resilient elements may respond or allow for the movement of the plate 606 only when encountering a higher amplitude sound wave and keep the plate 606 close to the base plate 602 until the amplitude of the sound wave is reduced to a certain level. Accordingly, the resilient elements can be tuned to respond to any number of amplitudes.

[0049] Fig. 6C illustrates a top view of a similar structure illustrated in Figs. 6A and 6B. It can be appreciated that many embodiments may provide for a number of spaces 612 between the resilient elements 610. These spaces 612 can allow sound to be passed through the openings. Additionally, it can be appreciated many embodiments that allow for a rotational and perpendicular movement of the orifice plate 606 may naturally work to close off the spaces 612 as well as reduce the size of the opening 604 by which the sound wave can enter. Effectively, this reduction in the opening would act to reduce the amplitude of sound waves that enter the opening 604. Fig. 6D illustrates a progression of movement of the orifice plate 606 with respect to the base plate 602 in accordance with some embodiments.

[0050] Such views aid to help illustrate the manner in which many embodiments may operate in a self-damping or tunable manner in accordance with the corresponding force. In accordance with many embodiments, the plurality of orifice plate and resilient element combinations may move in singularity or in unison with each of the other plurality of plate’s base on the amplitude and direction of the air pressure waves induced from corresponding sound. As discussed above the tunability of the resilient elements can play a key role in what sound can be allowed to enter the openings and subsequently be transmitted along a sound path. It can be appreciated that such structures can be applied in a variety of different applications including, but not limited to, hearing protection devices. Additionally, it can be appreciated that some embodiments may utilize a single resilient structure, while other embodiments may use multiple structures in a matrix to reduce the sound transmission.

[0051] Turning now to Fig. 7A other embodiments of a micro-architected structure can be illustrated. In accordance with some embodiments, a micro-architected structure can be constructed of multiple resiliently moveable components that move in response to a force being applied. Some embodiments of a micro-architected structure 700 may have a paddle element 702 and a stem portion 704. The paddle element 702 can be configured to directly interact with a force produced from a sound wave and may be resiliently connected to the stem portion 704 such that it can move in a variety of directions depending on the force from the sound wave. Additionally, the stem portion 704 may be resiliently connected to knee elements 706 through multiple resilient connections 708. Accordingly, when the paddle portion interacts with a pressure wave generated by some type of noise, it can move and subsequently result in the movement of the knee elements 706. The movement of the knee elements 706 can act as a method or manner to close the openings 710 that may exist between multiple paddle elements. For example, when a sound pressure wave interacts with the paddles 702 the paddles can move slightly towards a base element 712 of the structure 700. The movement of the paddles 702 is then translated to the knees 706 by way of the stem 704 and resilient connection elements 708. The movement of the knees 706 can then act to close off the openings 710 between the paddles 702. Figs. 7B and 7C illustrate a side and top view, respectively, of embodiments of a matrix of multiple micro-architected elements based on the embodiment illustrated in Fig. 7A.

[0052] Figs. 7E-7F illustrate respective views (side, top, and isometric) of embodiments of a resilient micro-architected structure in motion when a force is applied. Accordingly, it can be illustrated that the force or pressure that may interact with the paddle(s) can result in the lateral movement of the knees towards the open spaced between the paddles 702. This can result in the effective reduction of noise or the amplitude of the incoming noise wave. Thereby, reducing the potential for damaging effects on hearing. It can be appreciated that under ambient conditions, or lower to no noise levels the paddles 702 and knees 706 may remain in an undisturbed state with the openings left undisturbed between the paddles 702. Additionally, many embodiments many allow for individual micro-architected to be acted upon or for all to be acted upon at any given time. For example, depending on the pressure generated from the sound wave, one or more paddles may be activated thereby activating the knees to close the openings. Likewise, the sound pressure wave may only partially activate the paddles and knees thereby only partially closing the openings. It can be appreciated that many embodiments may tune the resilient elements and connections to respond to any number of different sound wave amplitudes. For example, lower amplitudes may not activate the knees while higher amplitudes may.

[0053] In accordance with many embodiments, the small movement of the paddles can translate to a larger movement in the knees. For example, Figs. 8A through 8D illustrate the comparison between the movements of the paddles when compared to that of the knees for different situations or different forces over time. Fig. 8A illustrates the movement of the paddle given a first impulse or force applied. The oscillation of the paddle corresponds to that of the knees illustrated in Fig. 8B. Flowever, it can be seen the small movement of the paddle can result in a movement of the knees that is roughly ten times that of the paddle. Likewise, Figs. 8C and 8D illustrate a similar comparison given a different amplitude applied. Therefore, it can be appreciated that many embodiments may be tuned to respond to different amplitudes resulting in an effective reduction in sound transmission. Although certain configurations and designs of the various elements are illustrated, it should be understood that various embodiments might include any number of different designs and/or configurations to achieve the level of response desired by the micro-architected components. Additionally, it can be appreciated that the micro-architected component can be produced in a number of different methods including but not limited to additive manufacturing. Furthermore, any number of desired materials can be used to achieve the level of effective noise reduction and/or cancellation.

[0054] In accordance with numerous embodiments, as described above, micro- architected elements can be used individually or in groups as part of a matrix. For example, Figs. 9A and 9B illustrate an embodiment of a micro-architected element that can be manipulated by the interaction with sound pressure waves. For example, some embodiments may utilize configurations or portions thereof that function with a negative Poisson ratio. A negative Poisson ratio is where a material or structure under a force in one direction acts to increase in size in the other directions which is opposite from what a typical elastic response would be. In numerous embodiments, the force applied along the“y” axis may result in the increase in dimension of the device along the“x” and“z” axes. Figs. 9A through 9E illustrate embodiments that can operate utilizing a negative Poisson ratio in at least a portion of the structure. For example, figs. 9A and 9B illustrate an embodiment of a micro-architected structure 900 that may be movably connected to a matrix structure 902. The matrix structure 902 can operate using a negative Poisson ratio in which a force applied along one axis can cause the matrix to expand along the other axes rather than shrink. In numerous embodiments, the individual element 900 may consist of a plunger 904 that has an upper plate 905 connected to an elongated shaft 906 where the shaft is connected to an under side of the upper plate 905. In accordance with many embodiments, the elongated shaft 906 may be configured with one or more prongs 908 that extend laterally from the shaft and are configured to engage with one or more shutter elements 910. In many embodiments, the shutter elements 910 may have a portion or face 912 that is configured to cooperatively engage with an opposing face on the prongs 908. In addition to being engageable with the prongs 908, the shutter elements 910 may be moveably connected to the matrix framework 902. The matrix framework 902, in accordance with many embodiments, can act as a resilient or spring loading feature such that when an extending force is applied in any direction the shutter elements 910 can open or move toward the prongs 908 and engage with the prongs 908 in a snap like fit. Such engagement, according to many embodiments, can cause the plunger 904 to be in a fixed open position that allows for a separation between the shutter elements 910. Additionally, the fixed open position can act as a holding force that holds the position of the shutter elements in relation to the matrix and can thereby allow for the flow of various amplitudes of sound waves. In numerous embodiments, the micro- architected structure 900 may have additional wall elements 914 connected to the shutter elements 910 that can move based on the movement of the shutter elements 910. Accordingly, it can be appreciated that a space may be opened and closed between the wall elements 914 based on the position of the shutter elements. Thus, many such embodiments can be poised to allow sound to pass through the openings between the shutters and walls and the corresponding matrix 902. [0055] In accordance with many embodiments, the matrix structure, when pulled to open the shutters, provides stored energy in each of the elements and overall structure that may be released when in contact with the pressure from high amplitude sound impulses. Accordingly, in many embodiments, when the plunger upper plate 905 interacts with an incoming pressure wave from a sound impulse that is higher than desired, it may be forced in the direction toward the matrix structure 902 causing the plunger shaft prongs 908 to disengage from the shutters 910. Subsequently, the stored energy in the matrix structure 902 is released and allows the shutters to close as illustrated in Figs. 9C and 9D. In accordance with many embodiments, the individual plungers 904 may interact solo with an incoming impulse or may act in groups of two or more to close the openings that may further the production of vortexes within the sound stream thereby reducing the amplitude of the downstream sound. As can be seen by Figs. 9A and 9B the individual matrix elements may be configured with or without sidewall elements 912. Such elements may help many embodiments by improving the movement capabilities of the shutter elements 910 with respect to the plunger 904. Fig. 9D illustrates a sequential movement of the lattice structure 902 resulting in a movement of the shutter elements 910 towards the prongs 908 as an example of how some embodiments may function.

[0056] Although certain configurations and designs of the various elements are illustrated, it should be understood that various embodiments might include any number of different designs and/or configurations to achieve the level of response desired by the micro-architected components. Additionally, it can be appreciated that the micro- architected component can be produced in a number of different methods including but not limited to additive manufacturing. Furthermore, any number of desired materials can be used to achieve the level of effective noise reduction and/or cancellation.

[0057] Embodiments described herein illustrate various types of micro-architected components that can operate in a manner conducive to reducing the transmission of undesired sound waves by introducing a variety of vortices into the sound wave to reduce the amplitude of said waves. While the disclosure provides a number of examples of different components and structures it should be understood that any combination of one or more of the individual structures can be used to achieve the desired level of sound reduction.

SUMMARY & DOCTRINE OF EQUIVALENTS

[0058] As can be inferred from the above discussion, the above-mentioned concepts can be implemented in a variety of arrangements in accordance with embodiments of the invention. Specifically, embodiments of tunable structures may be implemented in any number of hearing protection structures or any structure used to limit and/or reduce the amplitude of projected sound. Achieving such functionality, according to embodiments, involves the implementation of special arrangements/designs between subsystems described above, and their equivalents.

[0059] Accordingly, although the present invention has been described in certain specific aspects, many additional modifications and variations would be apparent to those skilled in the art. It is therefore to be understood that the present invention may be practiced otherwise than specifically described. Thus, embodiments of the present invention should be considered in all respects as illustrative and not restrictive.