Patent Publication Number: US-2023146091-A1

Title: Airfield systems, devices, and methods

Description:
CROSS REFERENCE 
     This application claims priority benefit of U.S. Provisional Patent Application No. 63/263,843 filed Nov. 10, 2021, and titled, “AIRFIELD SYSTEMS,” which is incorporated herein by reference in its entirety. 
     All applications for which a foreign or domestic priority claim is identified in the Application Data Sheet as filed with the present application are hereby incorporated by reference under 37 CFR 1.57. 
    
    
     FIELD 
     The disclosure relates generally to the field of airfield barriers. Specifically, the application relates to the field generating airfield barriers with purified air, devices for generating airfields, methods of using such devices, and methods for manufacturing such devices. 
     BACKGROUND 
     Infectious aerosols are generated by people who are infected with viruses or bacteria, including those having the common cold, influenza, and/or coronavirus infection. The aerosols from carriers of the infection may comprise a collection of pathogen-laden particles in air. These aerosol particles may deposit onto or be inhaled by others who are not infected causing new infections and for disease spread. 
     SUMMARY OF CERTAIN ASPECTS 
     Several embodiments disclosed herein pertain to airfield generating devices (e.g., airfield generators), methods of using the same, and methods for manufacturing the same. In several embodiments, these devices are useful in inhibiting or preventing the transmission of infectious diseases, pollutants, allergens, odors, etc. The prevention and/or reduction of transmission of infection and/or disease-causing aerosols is especially important in today&#39;s society. For example, the COVID-19 (the disease caused by the novel coronavirus SARS-CoV2) pandemic caused public activity to substantially halt in the United States and other countries around the world. The risks to health associated with SARS-CoV2 resulted in disruptions in normal daily life and caused a massive economic impact, resulting in mass layoffs and closures of businesses just a few weeks into the crisis. These shutdowns were especially detrimental to businesses where close interactions are the norm, such as restaurants, classrooms, libraries, etc. Several embodiments disclosed herein provide devices configured to address issues with the transmission of pathogens. 
     In several embodiments, the devices (e.g., airfield generators) disclosed herein generate an air barrier (e.g., an airfield) between subjects. In several embodiments, the air barrier comprises fast moving, clean air. In several embodiments, the air barrier separates one subject&#39;s air environment from a second subject&#39;s air environment. In several embodiments, the moving air in the generated air barrier captures and/or pushes contaminated aerosols from the first subject away from the second subject so that the second subject is not exposed to pathogens from the first subject. In several embodiments, the velocity of the air in the airfield is sufficiently high so as to substantially inhibit or prevent aerosols and/or pathogens from breath, sneezes, and/or coughs from passing through the airfield. In several embodiments, the velocity of the air in the airfield is sufficiently high so as to reduce to a safe and/or non-transmissible level aerosols and/or pathogens from breath, sneezes, and/or coughs from passing through the airfield. In several embodiments, the velocity of the air in the airfield is sufficiently high so as to reduce particulate levels in aerosols and/or pathogens from breath, sneezes, and/or coughs from passing through the airfield. 
     In several embodiments, the airfield generator may be supplied with clean air from an outside source of clean air (e.g., an air tank, etc.). Alternatively, in several embodiments, the airfield generator is adapted to generate clean air from contaminated air to generate the airfield and a clean air environment. For example, in several embodiments, the airfield generator may be equipped with one or more filters configured to remove pathogens from the air. These filters may be used to generate clean and/or pure air that is accelerated by the airfield generator to produce the airfield barrier. For example, the airfield generator may be configured to use recycled air from a room in which the airfield generator is located to generate the airfield. As will be appreciated, the airfield generator may also act as a whole room air purifier. As illustration, in several embodiments, the airfield generator may be configured to pull air from the room in which the airfield generator resides into an air intake of the airfield generator, to filter and/or purify the air, to accelerate the air to a velocity sufficient to provide an airfield, and to expel the air as an airfield through an outlet of the airfield generator. In several embodiments, the air of the airfield circulates back into the airfield generator for recycling, cleaning, and continued generation of the airfield. Alternatively or additionally, the airfield generator may be configured to work with an existing HVAC system for buildings or rooms. For example, the airfield generator may acquire air from a supply vent of an HVAC system in an existing room and may be configured to direct exhaust air (e.g., from the airfield) to an air intake vent for the HVAC system in the room. 
     In several embodiments, advantageously, the airfield generator is compact, modular, and/or portable. In several embodiments, the airfield generator is configured to be installed as part of a structure (and/or to be retrofitted to a structure) without effecting the normal use of the structure. In several embodiments, the airfield generator is configured to attach to and/or inhibit or prevent the transmission of pathogens across structures. In several embodiments, the structures may include tables, desks, cubbies, workstations, etc. In several embodiments, when adapted to be used with a particular structure (such as a desk, table, etc.), the airfield generator is compact enough to provide little or no interference with the space beneath the structure (e.g., the leg space under the desk or table). 
     Existing wind-generating units (e.g., motors, fans, etc.) that are sufficiently powerful to provide adequate velocity of air to be used as an airfield are unacceptably noisy. The noise level generated inhibits or prevents the use of such wind-generating units in situations where the use of airfield generator would be desired. For example, excessive noise in a restaurant or classroom is not desirable and inhibits or prevents subjects from engaging in conversations at normal volume levels (about 60-70 dB). In several embodiments, advantageously, the airfield generator comprises one or more sound dampening features that absorb sound generated from the wind-generating unit (e.g., motor and/or fan) of the airfield generator. In several embodiments, the dampening feature reduces the noise level of the wind generating unit by equal to or at least about: 10 dB, 20 dB, 30 dB, 40 dB, 50 dB, or ranges including and/or spanning the aforementioned values. 
     In several embodiments, the airfield generator comprises a housing. In several embodiments, the airfield generator housing is configured to engage a filter system. In several embodiments, the airfield generator housing comprises a base. In several embodiments, the base comprises at least one air intake, an internal cavity providing an air passage through the base, and a filter system housing. In several embodiments, the filter system housing is provided within the air passage. In several embodiments, the airfield generator housing comprises or further comprises an outlet. In several embodiments, the outlet comprises an upwardly directed opening configured to generate an airfield. In several embodiments, the outlet is in fluid communication with the air passage of the base. In several embodiments, the airfield generator comprises a motor. In several embodiments, the motor is positioned at least partially within the internal cavity. In several embodiments, the motor is configured to generate an air flow from an ambient environment surrounding the airfield generator. In several embodiments, the motor generates airflow through the filter system and out of the airfield generator via the outlet of the housing thereby generating an airfield. In several embodiments, the airfield generated by the outlet provides a barrier (e.g., airfield) between a first side of the airfield and a second side of the airfield. In several embodiments, the airfield is configured to inhibit passage of aerosol particles through the airfield from the first side of the airfield to the second side of the airfield. 
     Any of the embodiments described above, or described elsewhere herein, can include one or more of the following features. No features are essential or critical. 
     In several embodiments, the airfield generator comprises the filter system while in other embodiments the filter system is separate from the airfield generator. In several embodiments, the filter system is configured to be engageable with the housing. In several embodiments, the filter system is configured to filter air passing into the airfield generator via the at least one air intake and through the airfield generator via the air passage. 
     In several embodiments, the outlet of the housing extends between a first side of the housing and a second side of the housing. In several embodiments, the outlet is a shape appropriate to generate first and second air environments that are substantially separated from one another by the airfield. In several embodiments, the outlet is a shape appropriate to generate air of sufficient velocity to provide the airfield. In several embodiments, the outlet has a dimension in one direction that is larger than its direction in a second direction. For example, in several embodiments, the outlet has a length measured in a direction proximal to one side of the housing and extending distally to a second side of the housing. In several embodiments, the outlet also has a width. In several embodiments, the length of the outlet is greater than its width. In several embodiments, the ratio of the length of the outlet to the width of the outlet is equal to or at least about: 30:1, 20:1, 15:1, 10:1, 15:2, 5:1, 5:2, and ratios between the aforementioned ratios. In several embodiments, the length of the outlet runs along a width of an object for which separate air environments are desired. For example, in several embodiments the length of the outlet is placed along the width of a table separating two equal or non-equal portions of the table along the length of the table. In several embodiments, when users are seated at the heads of the table, the airfield provides a separation between the air environment of the subjects. In several embodiments, the outlet may comprise one or more fins (e.g., adjustable or nonadjustable fins). In several embodiments, adjustable fins may allow a user to direct the air of the airfield in a particular direction (e.g., away from a particular user, toward a vent intake of the room, etc.). 
     In several embodiments, the filter system comprises a plurality of filters. In several embodiments, the plurality of filters comprises at least a first filter and a second filter. In several embodiments, the first filter has a first parameter and the second filter has a second parameter. In several embodiments, the first parameter is different than the second parameter. In several embodiments, the first parameter and the second parameter comprise at least one of a filter size, a filtering capacity, or a filter shape. In several embodiments, the air intake of the airfield generator comprises a first and a second air intake. In several embodiments, the first filter is configured to engage with a first filter housing of the airfield generator housing and is configured to filter a first portion of air traveling into the base through the first air intake. For example, the first filter may engage a first filter dock of the housing. In several embodiments, the second filter is configured to engage with a second filter housing of the base, the second filter being configured to filter a second portion of air traveling into the base through the second air intake. 
     In several embodiments, the internal cavity of the base extends widthwise between a first side of the housing (or a corresponding first side of the base) and a second side of the housing (or corresponding second side of the base) providing a width of the internal cavity. In several embodiments, the internal cavity has a length that extends through the base from an entrance to an exit of the internal cavity. In several embodiments, the first filter is proximal to the entrance of the internal cavity. In several embodiments, the second filter is proximal to the exit of the internal cavity. 
     In several embodiments, the length of the outlet of the housing spans (or substantially spans) the width of the internal cavity and/or air passage of the base. In several embodiments, the length of the outlet is greater than the width of the internal cavity. In several embodiments, the length of the outlet is approximately the same size as the width of the internal cavity. In several embodiments, the ratio of the length of the outlet to the width of the internal cavity is equal to or at least about: 2:1, 3:2, 4:3, 5:4, 6:5, 1:1, or ratios between the aforementioned ratios. 
     In several embodiments, the second filter is a polygonal filter having a filtering portion extending along a length of the second filter between a proximal end portion and a terminal end portion. In several embodiments, the proximal end portion and the terminal end portion are a corresponding polygonal shape visible when viewed along the length of the second filter (e.g., a triangular shape, square shape, pentagonal shape, hexagonal shape, etc.). In several embodiments, the length of the second air filter is sufficient to span the width of the internal cavity and/or air passage of the housing. In several embodiments, the second filter housing is polygonal in shape (e.g., having a triangular shape, a square shape, a pentagonal shape, a hexagonal shape, etc.). In several embodiments, the polygonal shape of the second filter housing corresponds to the polygonal shape of the polygonal filter. In several embodiments, the polygonal shape of the second filter housing is apparent when viewing the base from its side. In several embodiments, the second filter housing is configured to receive the second filter through a filter housing aperture. In several embodiments, the filter housing aperture is polygonal. In several embodiments, the second filter may be slide into the second filter housing through the width of the base. In several embodiments, when placed in the second filter housing, the second filter spans the internal cavity such that air traveling through the second air intake is forced through the second filter and into the internal cavity. 
     In several embodiments, the second filter comprises at least a first side, a second side, and a third side defined by vertices of the polygonal shape, wherein the first side defines a first filtering surface of the filtering portion of the second filter, and wherein the second side defines at least a second filtering surface of the filtering portion of the second filter. In several embodiments, as air passes through the second filter, the air flows through at least the first filtering surface and/or the second filtering surface of the second filter. In several embodiments, the second filter comprises a triangular pocket filter. In several embodiments, the filter system comprises a triangular pocket filter. 
     In several embodiments, the housing comprises a first engagement mechanism, wherein the filter system comprises a second engagement mechanism, and wherein the first engagement mechanism is configured to removably receive the second engagement mechanism to removably engage the filter system with the housing. 
     In several embodiments, the motor comprises an electric motor, such as an inductive motor. The motor can comprise a fixed or variable speed motor. In some embodiments, the motor operates on AC power and in other embodiments the motor operates on DC power. In several embodiments, the motor is configured to generate an air flow of at least 370 cubic feet per minute. In several embodiments, the motor is configured to generate an air flow of equal to or at least about: 100 cubic feet per minute, 250 cubic feet per minute, 350 cubic feet per minute, 400 cubic feet per minute, 450 cubic feet per minute, 500 cubic feet per minute, 650 cubic feet per minute, 750 cubic feet per minute, 1000 cubic feet per minute, or ranges including and/or spanning the aforementioned values. For example, in several embodiments, the motor is configured to generate an air flow ranging from 100 cubic feet per minute to 1000 cubic feet per minute, from 350 cubic feet per minute to 400 cubic feet per minute, from 350 cubic feet per minute to 750 cubic feet per minute, etc. 
     In several embodiments, the upwardly directed opening is substantially vertical and/or is configured to direct air in a substantially vertical direction. In several embodiments, the outlet comprises a nozzle being configured to alter an air flow angle of the upwardly directed opening relative to a vertical direction. In several embodiments, the nozzle is configured to alter the air flow angle between 0 degrees and 45 degrees relative to the vertical direction. 
     In several embodiments, the housing is configured to seal the internal cavity. 
     In several embodiments, the airfield generator further comprises a sterilization system (e.g., other than the filter system). In several embodiments, the sterilization system is configured to sterilize at least one of the housing, the motor, the filter system housing or the filter system. 
     In several embodiments, the airfield generator further comprises at least one noise attenuation element. In several embodiments, the noise attenuation element is configured to reduce noise produced by the airfield generator. 
     In several embodiments, the housing is positioned on a support structure, and wherein the airfield generator is configured to generate the airfield such that the upwardly directed opening is angled relative to a top surface of the support structure. 
     In several embodiments, the airfield is generated using air from at least one of the first side of the airfield, the second side of the airfield, or both. 
     In several embodiments, the airfield generator is configured to reduce transmission of particulates sized 0.3 to 1 micron in the air at an efficiency of at least 75%, 80%, 90%, 95%, 97.5%, 99%, or 99.9%. In several embodiments, the airfield generator is configured to transmission of reduce particulates sized greater than 1 micron in the air at an efficiency of at least 75%, 80%, 90%, 95%, 97.5%, 99%, or 99.9%. In several embodiments, the particle reduction efficiency is accomplished at a flow rate of 100 cubic feet per minute, 250 cubic feet per minute, 350 cubic feet per minute, 400 cubic feet per minute, 450 cubic feet per minute, 500 cubic feet per minute, 650 cubic feet per minute, 750 cubic feet per minute, 1000 cubic feet per minute, or ranges including and/or spanning the aforementioned values. In several embodiments, the efficiency of reduction of particulate transmission may be measured across a given distance between a first point (where the particulate is generated) and a second point (where the amount of particulate is measured). To measure efficiency, the amount of particulate is measured at the second point in a system lacking an airfield generator. This amount of particulate is then compared to the amount of particulate measured at the second point in a second system having an airfield generator separating the first and second points. In several embodiments, the reduction in particle transmission includes particles generated from breath during respiration, talking, coughing, and/or sneezing. 
     In several embodiments, the airfield generator is configured to reduce incidences of infectious disease transfer, and wherein the infectious diseases is a common cold, influenza, and/or COVID. 
     Several embodiments pertain to an airfield generator comprising a housing comprising a base and an outlet. In several embodiments, the airfield generator comprises a first filter being configured to filter air passing through the first filter, the first filter comprises a first parameter. In several embodiments, the airfield generator comprises a second filter being configured to filter air passing through the second filter, the second filter comprising a second parameter, the second parameter being different than the first parameter. In several embodiments, the airfield generator comprises a motor being positioned at least partially within the housing. In several embodiments, the motor is configured to generate air flow from an ambient environment, through at least one of the first filter or the second filter, and through the outlet of the housing to generate an airfield, the airfield comprising air flow of filtered air traveling in an upward direction from the outlet of the housing. 
     In several embodiments, the first parameter and the second parameter comprise at least one of a filter size, a filtering capacity, or a filter shape. In several embodiments, the first filter is configured to engage with a first filter housing and is configured to filter air traveling into the base through a first air intake of the first filter housing. For example, the first filter may engage a first filter dock of the housing. In several embodiments, the second filter is configured to engage with a second filter housing of the base, the second filter being configured to filter air traveling into the base through a second air intake of the second filter housing. 
     In several embodiments, the second filter is a polygonal filter having a filtering portion extending along a length of the second filter between a proximal end portion and a terminal end portion. In several embodiments, the second filter comprises at least a first side, a second side, and a third side defined by vertices of the polygonal shape, wherein the first side defines a first filtering surface of the filtering portion of the second filter, and wherein the second side defines at least a second filtering surface of the filtering portion of the second filter. In several embodiments, as air passes from the base to the outlet through the second filter, the air flows through at least the first filtering surface and/or the second filtering surface of the second filter. In several embodiments, the second filter comprises a triangular pocket filter. In several embodiments, the filter system comprises a triangular pocket filter. 
     In several embodiments, the housing comprises a first engagement mechanism, wherein the filter system comprises a second engagement mechanism, and wherein the first engagement mechanism is configured to removably receive the second engagement mechanism to removably engage the filter system with the housing. 
     In several embodiments, the motor comprises an inductive motor. In several embodiments, the motor is configured to generate an air flow of at least 370 cubic feet per minute. 
     In several embodiments, the upwardly directed opening is substantially vertical and/or is configured to direct air in a substantially vertical direction. In several embodiments, the outlet comprises a nozzle being configured to alter an air flow angle of the upwardly directed opening relative to a vertical direction. In several embodiments, the nozzle is configured to alter the air flow angle between 0 degrees and 45 degrees relative to the vertical direction. 
     In several embodiments, the housing is configured to seal the internal cavity. 
     In several embodiments, the airfield generator further comprises a sterilization system (e.g., other than the filter system). In several embodiments, the sterilization system is configured to sterilize at least one of the housing, the motor, the filter system housing or the filter system. 
     In several embodiments, the airfield generator further comprises at least one noise attenuation element. In several embodiments, the noise attenuation element is configured to reduce noise produced by the airfield generator. 
     In several embodiments, the housing is positioned on a support structure, and wherein the airfield generator is configured to generate the airfield such that the upwardly directed opening is angled relative to a top surface of the support structure. 
     In several embodiments, the airfield is generated using air from at least one of the first side of the airfield, the second side of the airfield, or both. 
     In several embodiments, the airfield generator is configured to reduce particulates sized 0.3 to 1 micron in the air at an efficiency of at least 75%, 80%, 90%, 95%, 97.5%, 99%, or 99.9%. In several embodiments, the airfield generator is configured to reduce particulates sized greater than 1 micron in the air at an efficiency of at least 75%, 80%, 90%, 95%, 97.5%, 99%, or 99.9%. In several embodiments, the particle reduction efficiency is accomplished at a flow rate of 100 cubic feet per minute, 500 cubic feet per minute, 650 cubic feet per minute, 1000 cubic feet per minute, 1500 cubic feet per minute, 2000 cubic feet per minute, 5000 cubic feet per minute, 7500 cubic feet per minute, or ranges including and/or spanning the aforementioned values. 
     In several embodiments, the airfield generator is configured to reduce incidences of infectious disease transfer, and wherein the infectious diseases is a common cold, influenza, and/or COVID. 
     Several embodiments pertain to an airfield generator comprising airfield generator comprising a housing comprising a base and an outlet. In several embodiments, the airfield generator comprises a filter being configured to filter air passing through the filter. In several embodiments, the airfield generator comprises an inductive motor being positioned at least partially within the housing, the motor being configured to generate air flow from an ambient environment, through the filter, and through the outlet of the housing to generate an airfield, the airfield comprising an airflow of filtered air traveling in an upward direction from the outlet of the housing. 
     In several embodiments, the filter is one of a plurality of filters. In several embodiments, the filter is a first filter and the plurality of filters comprises at least a second filter, the first filter having a first parameter, the second filter having a second parameter, and wherein the first parameter is different than the second parameter. 
     In several embodiments, the first parameter and the second parameter comprise at least one of a filter size, a filtering capacity, or a filter shape. In several embodiments, the first filter is configured to engage with a first filter housing and is configured to filter air traveling into the base through a first air intake of the first filter housing. For example, the first filter may engage a first filter dock of the housing. In several embodiments, the second filter is configured to engage with a second filter housing of the base, the second filter being configured to filter air traveling through a second air intake of the second filter housing. 
     In several embodiments, the second filter is a polygonal filter having a filtering portion extending along a length of the second filter between a proximal end portion and a terminal end portion. In several embodiments, the second filter comprises at least a first side, a second side, and a third side defined by vertices of the polygonal shape, wherein the first side defines a first filtering surface of the filtering portion of the second filter, and wherein the second side defines at least a second filtering surface of the filtering portion of the second filter. In several embodiments, as air passes through the second filter, the air flows through at least the first filtering surface and/or the second filtering surface of the second filter. In several embodiments, the second filter comprises a triangular pocket filter. In several embodiments, the filter comprises a triangular pocket filter. 
     In several embodiments, the housing comprises a first engagement mechanism, wherein the filter comprises a second engagement mechanism, and wherein the first engagement mechanism is configured to removably receive the second engagement mechanism to removably engage the filter with the housing. 
     In several embodiments, the airfield generator further comprises a cooling system to cool the motor. In several embodiments, the motor is configured to generate an air flow of at least 370 cubic feet per minute. In several embodiments, the motor is configured to generate an air flow of equal to or at least about: 100 cubic feet per minute, 250 cubic feet per minute, 350 cubic feet per minute, 400 cubic feet per minute, 450 cubic feet per minute, 500 cubic feet per minute, 650 cubic feet per minute, 750 cubic feet per minute, 1000 cubic feet per minute, or ranges including and/or spanning the aforementioned values. 
     In several embodiments, the upward direction is substantially vertical. 
     In several embodiments, the upwardly directed opening is substantially vertical and/or is configured to direct air in a substantially vertical direction. In several embodiments, the outlet comprises a nozzle being configured to alter an air flow angle of the upwardly directed opening relative to a vertical direction. In several embodiments, the nozzle is configured to alter the air flow angle between 0 degrees and 45 degrees relative to the vertical direction. 
     In several embodiments, the housing is configured to seal the internal cavity. 
     In several embodiments, the airfield generator further comprises a sterilization system (e.g., other than the filter system). In several embodiments, the sterilization system is configured to sterilize at least one of the housing, the motor, and the filter (e.g., the first or second filter). In several embodiments, the sterilizing system may comprise, for example, a UV light. 
     In several embodiments, the airfield generator further comprises at least one noise attenuation element. In several embodiments, the noise attenuation element is configured to reduce noise produced by the airfield generator. 
     In several embodiments, the housing is positioned on a support structure, and wherein the airfield generator is configured to generate the airfield such that the upwardly directed opening is angled relative to a top surface of the support structure. 
     In several embodiments, the airfield is generated using air from at least one of the first side of the airfield, the second side of the airfield, or both. 
     In several embodiments, the airfield generator is configured to reduce particulates sized 0.3 to 1 micron in the air at an efficiency of at least 75%, 80%, 90%, 95%, 97.5%, 99%, or 99.9%. In several embodiments, the airfield generator is configured to reduce particulates sized greater than 1 micron in the air at an efficiency of at least 75%, 80%, 90%, 95%, 97.5%, 99%, or 99.9%. In several embodiments, the particle reduction efficiency is accomplished at a flow rate of 100 cubic feet per minute, 250 cubic feet per minute, 350 cubic feet per minute, 400 cubic feet per minute, 450 cubic feet per minute, 500 cubic feet per minute, 650 cubic feet per minute, 750 cubic feet per minute, 1000 cubic feet per minute, or ranges including and/or spanning the aforementioned values. 
     In several embodiments, the airfield generator is configured to reduce incidences of infectious disease transfer, and wherein the infectious diseases is a common cold, influenza, and/or COVID. 
     Several embodiments pertain to a method for reducing incidences of infectious disease transfer. In several embodiments, the method comprises obtaining an airfield generator. In several embodiments, the method comprises activating the airfield generator. In several embodiments, the method comprises causing the motor to generate an air flow from an ambient environment surrounding the airfield generator, through the filter system, and out the outlet of the housing, thereby generating an airfield. In several embodiments, the infectious disease is caused by one or more of a Rhinoviruses, Coronavirus, influenza virus types A, B, C, D,  Streptococcus pneumoniae, Haemophilus influenzae, Moraxella catarrhalis, Staphylococcus aureus , other streptococci species, anaerobic bacteria, or gram negative bacteria. 
     Several embodiments pertain to a method for reducing symptoms of allergy. In several embodiments, the method comprises obtaining an airfield generator. In several embodiments, the method comprises activating the airfield generator. In several embodiments, the method comprises causing the motor to generate an air flow from an ambient environment surrounding the airfield generator, through the filter system, and out the outlet of the housing, thereby generating an airfield. In several embodiments, the allergy is a seasonal allergy or a food allergy. 
     Several embodiments pertain to a method for manufacturing an airfield generator. In several embodiments, the method comprises obtaining a housing. In several embodiments, the method comprises obtaining a filter system. In several embodiments, the method comprises obtaining a motor. In several embodiments, the method comprises assembling the housing with the motor. In several embodiments, the method comprises engaging the filter system with the housing. In several embodiments, the method comprises obtaining inserting the plurality of filters into the airfield generator. 
     Neither the preceding Summary nor the following Detailed Description purports to limit or define the scope of protection. The scope of protection is defined by the claims. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       The following drawings and the associated descriptions are provided to illustrate embodiments of the disclosure and do not limit the scope of the claims. Throughout the drawings, reference numbers are re-used to indicate correspondence between referenced elements. 
         FIGS.  1 A- 1 H  illustrate an exemplary airfield system in accordance with aspects of this disclosure. 
         FIG.  2 A  schematically illustrates a block diagram of an airfield generator in accordance with aspects of this disclosure. 
         FIG.  2 B  depicts a subsystem of airfield systems in accordance with aspects of this disclosure. 
         FIG.  3    depicts a flowchart illustrating a process of controlling an airfield generator in accordance with aspects of this disclosure. 
         FIGS.  4 A- 4 E,  5 A- 5 B,  6 A- 6 C,  7 ,  8 A- 8 D, and  9 A- 9 J  depict subsystems of airfield systems in accordance with aspects of this disclosure. 
         FIGS.  10 A- 10 B  depict an air flow path of an airfield generator in accordance with aspects of this disclosure. 
         FIG.  11    illustrates an exemplary airfield system in accordance with aspects of this disclosure. 
     
    
    
     DETAILED DESCRIPTION OF CERTAIN EMBODIMENTS 
     The disclosure describes various devices, systems, and methods for airfield systems and, in particular, airfield systems to generate separate zones of space using a filtered airfield. For example, the systems may filter an airfield using minimum efficiency reporting value (MERV) filters. 
     The disclosure will now be described with reference to the accompanying figures, wherein like numerals refer to like elements throughout. The following description is merely illustrative in nature and is in no way intended to limit the disclosure, its application, or uses. It should be understood that steps within a method may be executed in different order without altering the principles of the disclosure. Furthermore, embodiments disclosed herein can include several novel features, no single one of which is solely responsible for its desirable attributes or which is essential to practicing the systems, devices, and methods disclosed herein. 
     Generally, airfield generators of the disclosure may produce an airfield traveling at a sufficient speed (e.g., approximately 650 feet per minute and/or as disclosed elsewhere herein) across a set distance such that the airfield generator is configured to effectively increase a social distance between the two interacting people (e.g., people who are conversing, laughing, etc.) when the generator is placed in between the individuals. For example, the airfield generator may be configured to redirect any aerosols present in a first individual&#39;s breath (e.g., during talking, sneezing, coughing) such that the aerosols are directed away from another individual. For instance, the breath aerosol may be raised into a HVAC intake zone, rather than in the face of other people. In some instances, the airfield can include a volume of air that has been filtered through an optional filter set up, which can be utilized in multiple configurations to address different use cases. Generally, the airfield generators of the disclosure may also assist in increase air changes per hour, ACH change over, to decrease transmission of unfiltered air patriciates, e.g., due to close proximity transmission. 
     In several embodiments, the social distance between individuals separated by the airfield generator (relative to those not separated by the airfield generator) is increased by a distance of equal to or at least about: 5 feet, 10 feet, 15 feet, 20 feet, or ranges including and/or spanning the aforementioned values. In several embodiments, the equivalent social distance is increased by a factor of equal to or at least about: 2 times (e.g., 2×), 3×, 4×, 5×, 10×, 15×, or 20×, or ranges including and/or spanning the aforementioned values. 
     A. Overview of Airfield Systems 
       FIGS.  1 A- 1 G  illustrate an exemplary airfield system  100  in accordance with aspects of this disclosure.  FIGS.  1 A- 1 G  depict different views of the airfield system  100 . As depicted in  FIG.  1 A , airfield system  100  includes an airfield generator  101  and a structure  102 . The airfield generator  101  may generate an airfield  106 A from outlet  104 , as discussed below. For instance, airfield generator  101  may filter environmental air and output filtered air to generate the airfield  106 A. 
     The airfield generator  101  may be positioned so that airfield  106 A may separate distinct zones of space  106 B and  106 C, so that transmission of unfiltered air (and particulates therein) between the distinct zones of space  106 B and  106 C is reduced. For instance, the distinct zones of space  106 B and  106 C may be adjacent to the airfield generator  101  and separated by the airfield  106 A for at least a defined length (e.g., at least a length of the outlet  104  of the airfield generator  101 ). The airfield  106 A may pull ambient air in the distinct zones of space  106 B and  106 C into the airfield  106 A increasing airflow and circulation in the distinct zones of space  106 B and  106 C creating an air dam. 
     As depicted in  FIG.  1 A , the airfield  106 A may be generally directed in the z direction and extend along the x direction, to thereby separate the distinct zones  106 B and  106 C, for at least a portion along the x direction, in respective y directions. As used herein, the z direction may be a vertical direction (e.g., in a field of gravity), and the x direction and y direction may be lateral directions (referred to as front and back direction for the y direction, and left and right direction for the x direction). In some instances, the z direction may refer to a height of the airfield being generated at least partially in a direction of air flow, the x direction may refer to a length of the airfield being generated (e.g., along a major axis of the airfield), and the y direction may refer to a width or depth of the airfield (e.g., along a minor axis of the airfield). 
     Various embodiments of the airfield generator  101  as described herein may provide the benefits of producing a high-volume amount of compact air through the airfield  106 A with the use of a generator  101  that is compact in size. The airfield  106 A can be generated generally along the z direction in an upward direction. 
     The outlet  104  of the airfield generator  101  may be various shapes to output the airfield  106 A.  FIGS.  1 A- 1 G  illustrate an outlet  104  with a generally elongated rectangular shape. However, it will be understood that the outlet  104  may be any size or shape suitable to generate an airfield. For example, the outlet  104  may comprise a generally curved shape. In some instances, the curve may be configured such that at least one of the individuals in one of the distinct zones  106 B,  106 C is located at a focal point of the curve. The outlet  104  may have a width  103  in they direction. In some embodiments, the outlet  104  may have a constant width  103  across the outlet  104  in the x direction. In other embodiments, the width  103  may be different across the outlet  104  in the x direction. For example, the width  103  may be larger at the middle of the outlet  104  than the width  103  at the ends of the outlet  104  so the air speed is constant across the outlet  104  in the x direction. 
     In some embodiments, the outlet  104  may be a nozzle with a continuous opening. However, the outlet  104  may instead have a non-continuous opening, such as with a grate or other structure to inhibit or prevent foreign objects to enter the outlet  104 , while still allowing a continuous airfield  106 A to be output therefrom. 
     The outlet  104  may be adjustable to change one or more features of the airfield  106 A (e.g., a direction, angle relative to the surface of the structure  102 , size, air speed, volume of air generated, etc.). For instance, the outlet  104  may be adjustable to change an angle of air flow relative to a z axis, such as from forward to backward or backward to forward within a defined range of angles. For instance, the range may be ±45° relative to the z axis. The range may be ±15°, ±25°, ±35°, ±45°, ±50°, ±60°, ±70°, ±80°, or ranges including and/or spanning the aforementioned values. As an example, the outlet  104  may be hinged to thereby adjust the angle from the z direction at which the airfield  106 A is projected into space, thereby adjusting the distinct zones of space  106 B and  106 C. In some embodiments, the outlet  104  may be adjustable manually or electronically via a controller  216  (described below with reference to  FIG.  2 A ). In some embodiments, the outlet  104  may automatically move from forward to backward and backward to forward within at least a portion of the defined range of angles at a predetermined angular velocity and/or at predetermined intervals. In the case of a structure  102  with a surface (such as a table), the outlet  104  may protrude through the surface to a fixed height in the z direction from the surface. For instance, the protrusion of the outlet  104  may enable the outlet  104  to be adjusted through the defined range of angle without interfering with the surface. 
     Generally, the structure  102  may include various different forms of supports. As depicted in  FIGS.  1 A- 1 G , the structure  102  may be an item of furniture, such as a table. The structure  102  (e.g., table) may have a surface. The structure  102  may separate two or more groups of people in respective zones of space. However, one of skill in the art would recognize that the structure could alternatively be, for example, a counter (e.g., at a checkout/check-in of a business, at a bar, etc.), a mobile stand to support the airfield generator  101 , a wall fixture, a barrier (e.g., between office desks, cubicles, etc.), a portion of an HVAC system, a ceiling, a drop ceiling, a portion of a vehicle, etc. Therefore, generally, the structure  102  may be a physical object that may fix and hold the airfield generator  101  in place, so that the airfield generator  101  may generate the airfield  106 A and the distinct zones of space  106 B and  106 C. As an additional example,  FIG.  11    depicts an alternative airfield system  1100 . Airfield system  1100  may include the airfield generator  101  with a different structure  1102 . The different structure  1102  may be an article of furniture, such as a podium (as depicted), or otherwise. In various embodiments, the structure  102  comprises, and/or the airfield generator  101  is comprised, in a desk, podium, counter, table, wall or pony wall, ceiling, floor, etc. In some embodiments, the structure  102  comprises, and/or the airfield generator  101  is comprised, in a vehicle, such as a car or airplane (e.g., to generate an airfield barrier between adjacent occupants or passengers). 
     While only one airfield generator  101 , one airfield  106 A, and two distinct zones of space  106 B and  106 C are depicted in  FIG.  1 A , one of skill in the art would recognize that multiple (e.g., two or more) airfield generators  101  may be arranged to generate multiple (e.g., two or more) airfields  106 A to generate a plurality of zones of space  106 B and  106 C. Generally, the arrangement of airfield generators  101  (and their respective airfields  106 A) may define boundaries of the plurality of zones of space  106 B and  106 C. For instance, airfield generators  101  (and their respective airfields  106 A) may be orthogonal to each other, or arranged at an acute or obtuse angle with respect to each other and spaced a part to define the boundaries of the plurality of zones of space  106 B and  106 C. 
       FIGS.  1 B- 1 C  depict features of various embodiments of the airfield generator  101  from below the surface of the structure  102 , from front and back views, respectively, of the airfield generator  101 . One of skill in the art would recognize that, when the structure  102  does not include a surface, the airfield generator  101  may have the same components, but the outlet  104  may be changed (e.g., shortened) as the protrusion through the surface may not be necessary. In particular,  FIGS.  1 B- 1 C  depict a base  108 , a fan  109  (also called a blower), and a main filter housing  110  of airfield generator  101 . The fan  109  can comprise, for example, a centrifugal fan, axial fan, or otherwise.  FIGS.  1 D- 1 E  depict features of various embodiments of the airfield generator  101  from below the surface of the structure  102 , from a left and right views of the airfield generator  101 . In particular,  FIGS.  1 B- 1 C  depict a motor  114  and bypass inlets  116  of airfield generator  101 .  FIGS.  1 F- 1 G  depict features of various embodiments of the airfield generator  101  from below the surface of the structure  102 . In particular,  FIGS.  1 F- 1 H  depict various attachment systems  120 ,  122  and  124  of airfield generator  101 . 
     The base  108  may have an interior volume to receive filtered air from a main filter (e.g., in the main filter housing  110 ) and a rack filter  802  (e.g., via the bypass inlets  116  as illustrated in  FIGS.  8 A- 8 D ) into at least one cavity (e.g., as illustrated in  FIGS.  4 A- 4 E ) to pass the filtered air to the centrifugal fan  109 . The base  108  may also be configured to removably secure the centrifugal fan  109  and motor  114  to create a sealed interface therebetween during operation (e.g., from vibrations and attenuate noise). The base  108  may provide for a sealed interface to enclose and protect one or more components (e.g., the centrifugal fan  109  and the motor  114 ) from the external environment. For example, the base  108 , when closed, may provide for an internal cavity that is water-proof (or at least water-resistant) to inhibit unintended fluid (e.g., liquids) from entering into the internal cavity of the base  108 . 
     As illustrated in  FIGS.  1 F- 1 G , the attachment systems  120  and  122  may secure the base  108  to the structure  102 . For instance, attachment systems  120  and  122  may be a bracket, which may be discontinuous (such as attachment system  120 ) or continuous along a length of the base  108  (such as attachment system  122 ). The attachment systems  120  and  122  may use, e.g., fasteners to attach the base  108  to the structure  102 , but one of skill in the art would recognize that other approaches may be taken (e.g., adhesive, etc.). 
     In some embodiments, as shown in  FIG.  1 H , the attachment system  124  may secure the base  108  to the structure  102  via vibration dampeners  126 . The vibrations dampeners  126  may be straps, nylon straps, rubber, springs, wires, or any other vibration dampening connection. In some embodiments, the vibration dampeners  126  may be one or more pieces of rubber coupled to the base  108  and the structure  108 . In the embodiments, where the vibration dampeners  126  are straps or nylon straps, the vibration dampeners  126  may be secured to the base  108  via one or more connectors  128 . The connectors may be a metal plate screwed into the base  108 , or any other fastener for connecting the straps to the base  108 . 
     The vibration dampeners  126  may secure the base  108  to the structure  102  such that the base  108  is free floating. The vibration dampeners  126  may be coupled to the structure by connection system  130 . The connection system  130  may include a connecting portion  132  and an adjustment portion  134 . The connecting portion  132  may rotatably or movably couple the vibration dampeners  126  to the structure  102  such that when the base  108  moves or vibrates, the vibration dampeners  126  can move or vibrate relative to the structure  102  without transferring any movement or vibration to the structure  102 . In this way, when the motor  114  is powered and generating airfield  106 A, vibration or movement of the base  108  created by the motor  114  and the centrifugal fan  109  does not transfer, or is reduced from transferring, from the base  108  to the structure  102 . 
     The adjustment portion  134  may allow a user to change a length of the vibration dampeners  126 . The user may secure the base  108  to the structure  102  as shown in  FIG.  1 H  so the outlet  104  is below the structure  102 , or the user may use the  134  to shorten a length of the vibration dampeners  126  so the outlet  104  may extend through an opening  136  above the structure  102 . 
     In some embodiments, the opening  136  in the structure  102  may be larger than the outlet  104  so that if the outlet  104  is above the structure  102 , when the base  108  vibrates or moves, the outlet  104  may vibrate or move without contacting the structure  102 . 
     In some embodiments, the structure  102  may be a ceiling or a drop ceiling, and the base  108  may be secured to a secondary structure so the base  108  can be hung (e.g., upside down) above the structure  102 . The secondary structure may be a surface above a drop ceiling, a portion of an HVAC system or a surface near the portion of the HVAC system, or any other structure above or near the structure  102 . The base  108  may be uncoupled to the structure  102  so the movement or vibration of the base  108  will not be transferred to the structure  102 . The vibration dampeners  126  may reduce or eliminate caused nose cause by movement or vibration that may be transferred from the base  108  to the secondary structure. 
     The vibration dampeners  126  may reduce or eliminate vibration or movement of the structure  102  and/or reduce or eliminate sound caused by the vibration or movement of the structure  102 . 
     In the embodiments where the structure  102  or the secondary structure are a portion of an HVAC system or a surface near the portion of the HVAC system, the airfield generator  101  may provide purification to the HVAC system, and the base  108  may be positioned so the airfield  106 A is directed into the HVAC system. 
     With reference to  FIG.  1 B , the centrifugal fan  109  may receive filtered air from the at least one cavity, compress the filtered air to increase the airflow speed of the filtered air, output the compressed filtered air to the outlet  104  to thereby generate the airfield  106 A. The motor  114  may control operation of the centrifugal fan  109  by rotating impellers  706  (e.g., as illustrated in  FIG.  7   ) of the centrifugal fan  109  at fixed or various speeds via a shaft  912  (e.g., as illustrated in  FIG.  9 J ). For instance, the motor  114  may cause the impellers  706  of the centrifugal fan  109  to rotate at a fixed rotation per minute (RPM). Alternatively, the motor  114  may cause the impellers  706  to rotate at various RPMs, such as from a first RPM to a second RPM to increase airflow speed of the airfield  106 A from a first airflow speed to a second airflow speed. 
     Generally, the centrifugal fan  109  may extend axially along an axis of rotation of the impellers  706 , with a first opening in a shroud of the centrifugal fan  109  to receive the filtered air and a second opening in the shroud to output the compressed filtered air to the outlet  104 . The first and second openings may be substantially similar in length to each other and to the outlet  104 . The centrifugal fan  109  may be positioned along one end of the base  108  to be secured to the base  108  by, e.g., fasteners. For instance, the centrifugal fan  109  may be adjacent to, abut, or overlap an edge of the base  108  on a front or rear of the base  108 . The motor  114  may be attached to the centrifugal fan  109 . 
     In some instances, the motor  114  can comprise an inductive or alternating-current (AC) motor. The inductive motor can advantageously increase the durability and/or power of the motor  114  to improve the filtration capability of the airfield system  100 . For example, an increased power may permit the motor  114  to force an increased amount of air, relative to alternative motor designs, through higher quality filtration components. The higher quality filter components may include an increased number and/or rating of the filter. In some instances, the motor  114  may be configured to generate an airfield  106 A with air passing through at a rate of about 370 cubic feet per minute. The motor  114 , in some embodiments, may be configured to generate an airfield  106 A with air passing through at a rate of about 275 cubic feet per minute if the air is being filtered through two separate MERV 8 filters. An inductive motor may advantageously provide a steady, reliable movement of air relative to alternative designs that may result in variability of the rate of air flow throughout use. 
     The main filter housing  110  may be configured to removably receive a main filter (e.g., a one or more filters) to filter a first portion of environmental air  112  and pass the filtered air to the at least one cavity via a main inlet  426  (e.g., as illustrated in  FIG.  4 D ). Generally, the main filter housing  110  may be a cuboid shape that is generally rectangular with a height to receive the one or more filters in an ordered arrangement (e.g., as illustrated in  FIG.  6 A- 6 C ). Generally, the one the more filters of the main filter may include at least one of a pre-screen, a charcoal filter, or one or more MERV filters. Details of the one of more filters and the ordered arrangement thereof are discussed below with respect to  FIGS.  6 A- 6 C . 
     The main inlet  426  may be positioned on an opposite end of the base  108  from the centrifugal fan  109 . The main inlet  426  may be positioned on a bottom of the base  108  so that the first portion of environmental air  112  is drawn into the at least one cavity via the main inlet  426  in a vertical direction through the one or more filters of the main filter housing  110 . The main inlet  426  may be formed in the bottom of the base  108  by walls  412 - 416  (e.g., as illustrated in  FIG.  4 B ), cover  418  (e.g., as illustrated in  FIG.  4 C ), and rack holder  420  (e.g., as illustrated in  FIG.  4 D ) creating a seal between the sealed interior volume of the base  108  and the main filter housing  110 . 
     The bypass inlets  116  may be openings in the walls  412 - 416  of the base  108  on respective lateral (e.g., left and right) sides. The bypass inlets  116  may receive a rack filter  802  (e.g., as illustrated in  FIGS.  8 A- 8 D ) in rack holder  420  to filter a second portion of environmental air  118  and pass the filtered air to the at least one cavity. For instance, the bypass inlets  116  may be positioned on an opposite end of the base  108  from the centrifugal fan  109 . As an example, the bypass inlets  116  may be generally triangular, so that generally triangular rack filters  802  may be inserted through the bypass inlets  116 . The generally triangular rack filters  802  can be configured to create an airtight or substantially airtight seal with the structure of the bypass inlets  116 . Moreover, the bypass inlets  116  may be positioned in a corner opposite the centrifugal fan  109 , as the centrifugal fan  109  may (in the case of no bypass inlets  116  and rack filter  802 ) create a dead zone of filtered air in the at least one cavity due to vortices in the circular motion from the main inlet  426  to the first opening of the centrifugal fan  109 . In this manner, the bypass inlets  116  and the rack filter  802  may increase the volumetric flow rate of filtered air, while avoiding a dead zone of filtered air in the at least one cavity. The rack filter  802  may be a MERV 13 level triangulated pocket filter. In some embodiments, the bypass inlets  116  may also draw air over the motor  114 , thereby cooling the motor  114 . 
     In some embodiments, the main filter housing  110  may be omitted (e.g., as illustrated in  FIG.  4 E ), so that unfiltered air is received in the at least one cavity. In this case, the airfield  106 A may still operate to reduce transmission of particulates as the airfield  106 A may have an airspeed high enough to redirect unfiltered air from one zone of space to not enter another zone of space. For instance, this may reduce construction and operational cost of the airfield generator  101 , while still providing a reduction in transmission of particulates between each zone of space. For instance, as a result of filtering the environmental air using only the bypass inlets  116  with the rack filter  802  and generating an airfield  106 A, each zone of space may have reduced transmission of unfiltered air and reduce the effective social distance between different groups in each zone. 
     In some embodiments, the main filter housing  110  may be omitted for a polygonal filter  502  (e.g., as illustrated in  FIG.  5 A ). In this case, the environmental air may be filtered but not as thoroughly as if the main filter housing  110  was used. For instance, this may reduce construction and operational cost of the airfield generator  101 , while still providing filtered air to the at least one cavity. The airfield  106 A may have an airspeed high enough to redirect unfiltered air from one zone of space to not enter another zone of space. Therefore, in this case, the particulates may be both filtered out of the air to be used as the airfield  106 A (thereby reducing particulates in the environment) and redirected so as not interact with a different zone of space. For instance, as a result of filtering the environmental air using the polygonal filter  502  and the bypass inlets  116  with the rack filter  802  and generating an airfield  106 A, each zone of space may have reduced transmission of unfiltered air and reduce the effective social distance between different groups in each zone. 
     In some embodiments, the main filter housing  110  may be used to provide a higher level of filtration of the unfiltered air than using the polygonal filter  502 . While this may cost more to construct and operate than the previous two embodiments, the increase in filtration may enable indoor activities with reduced transmission of particles between the zones of space. For instance, as a result of filtering the environmental air using the main filter housing  110  and the bypass inlets  116  with the rack filter  802  and generating an airfield  106 A, each zone of space may have reduced transmission of unfiltered air and reduce the effective social distance between different groups in each zone. 
     In some embodiments, the main filter housing  110  and/or the polygonal filter  502  may be removably engaged with the base  108 , so that a user of the airfield generator  101  may remove the main filter housing  110  and/or the polygonal filter  502 . For instance, the main filter housing  110  and/or the polygonal filter  502  may be interchangeable to interface with the main inlet  426 , or omitted entirely. Each of the main filter housing  110  and the polygonal filter  502  may have engagement mechanisms that correspond to an engagement mechanism on the base  108 . For instance, the user may modify the configuration depending on application. Moreover, the one or more filters of the main filter housing  110  may be replaced with a same or different filters, depending on application. For example, for a first application if the user wants a high level of airflow or high air speed through the outlet  104 , and a high level of filtration of air is not important for the first application, the user may replace the one or more filters of the main filter housing  110 , the polygonal filter  502 , and/or the rack filter  802  with alternative one or more filters of the main filter housing  110 , the polygonal filter  502 , and/or the rack filter  802  with a lower MERV rating to increase the level of airflow or air speed of the airfield generator  101 . For a second application, if a high level of filtration is important, and the level of airflow or air speed through outlet  104  is not important for the second application, the user may replace the one or more filters of the main filter housing  110 , the polygonal filter  502 , and/or the rack filter  802  with alternative one or more filters of the main filter housing  110 , the polygonal filter  502 , and/or the rack filter  802  with a higher MERV rating to increase the level of filtration of the airfield generator  101 . Furthermore, the one or more filters of the main filter housing  110 , the polygonal filter  502 , and the rack filter  802  may be removable to clean the various filters to ensure proper filtration. 
     In some embodiments, the airfield generator may have a housing, a filter system, and a motor. The housing may include: a base comprising an air intake, an internal cavity providing an air passage through the base, and a filter housing, the filter housing being within the air passage; and an outlet. The outlet can comprise an opening (e.g., an upwardly directed opening) configured to generate an airfield, the outlet being in fluid communication with the air passage of the base. The outlet can extend between a first side of the housing and a second side of the housing. The filter system may be engageable with the housing. The filter system may be configured to filter air passing through the airfield generator via the air passage. The motor may be positioned at least partially within the internal cavity. The motor may be configured to generate an air flow from an ambient environment surrounding the airfield generator, through the filter system, and out of the airfield generator via the outlet of the housing thereby generating an airfield. The airfield generated by the outlet may provide a barrier between a first side of the airfield and a second side of the airfield. The airfield may be configured to inhibit passage of aerosol particles through the airfield from the first side of the airfield to the second side of the airfield. Moreover, the housing may include a first engagement mechanism. The filter system may include a second engagement mechanism. The first engagement mechanism may be configured to removably receive the second engagement mechanism to removably engage the filter system with the housing. 
     In some embodiments, the filter system may include a plurality of filters. At least one of the filters may be insertable into the filter housing to filter the air through the air intake and at least another filter may be insertable into the filter system to filter a separate portion of air. In some embodiments, the plurality of filters may include at least a first filter having a first parameter and at least a second filter having a second parameter. The first parameter may be different than the second parameter. The first parameter and the second parameter comprise at least one of a filter size, a filtering capacity, or a filter shape. A filter size may indicate a weight or volume of the filter (e.g., in standard sizes or as physical attributes). Filter capacity may indicate a property of the filter to remove a certain percentage of particulates at various cubic feet per minute. For example, a filter capacity may be a filter&#39;s ability to capture particles of various sizes, such as at least 0.3 microns, at least 1 microns, at least 3 micros, etc. For instance, filter capacity may be indicated by a MERV rating, such as MERV 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, or 16. It will be understood that any component of any filter or filter system described herein may comprise any type of filter described herein or any combination thereof. 
     In some embodiments, the first filter may be configured to fit within the housing and may be configured to filter air traveling into the base through the air intake. In some embodiments, the second filter may be configured to fit within the filter housing of the base and be configured to filter air from the air passage prior expulsion through the outlet as the airfield. 
     In some embodiments, the first or second filter may be a polygonal filter having a filtering portion extending along a length of the first or second filter between a proximal end portion and a terminal end portion. The proximal end portion and the terminal end portion may be a corresponding polygonal shape visible when viewed along the length of the second filter. The first or second filter may comprise at least a first side, a second side, and a third side defined by vertices of the polygonal shape, where the first side defines a first filtering surface of the filtering portion of the first or second filter, and wherein the second side defines at least a second filtering surface of the filtering portion of the first or second filter. As air passes from the base to the outlet through the first or second filter, the air flows through at least the first filtering surface and the second filtering surface of the first or second filter. The first or second filter comprises a pocket filter with a polygonal shape, such as a triangular pocket filter. For example, the polygonal shape may comprise any one of a triangle, rectangle, pentagon, hexagon, or any of shape as desired. 
       FIG.  2    schematically illustrates a block diagram of an airfield generator  200  in accordance with aspects of this disclosure. For instance, the airfield generator  200  may be a part of the airfield system  100 , discussed above. As depicted in  FIG.  2   , the airfield generator  200  may include one or more of a main filter  204 , a rack filter  206 , at least one cavity  208 , a fan  210  (also called a blower), an outlet  212 , a controller  216 , sensor(s)  218 , sanitation system  220 , or any combination thereof. The airfield generator  200  may take in environmental air  202  and output an airfield of filtered air  214 , so as to generate at least two zones of space separated by the airfield of filtered air  214 . In operation, respective portions of environmental air  202  may be received by and filtered by the main filter  204  and the rack filter  206 , respectively. The filtered air may be directed into the at least one cavity  208  to be gathered in a sealed interior and received by the fan  210 . Fan  210  may compress the received filtered air and output the compressed air to the outlet  212 . The outlet  212  may output the airfield of filtered air  214 , so as to generate at least two zones of space separated by the airfield of filtered air  214 . 
     The controller  216  may control the fan  210 , based on data from the sensor(s)  218  and/or user inputs. For instance, the controller  216  may cause the fan  210  of the airfield generator  200  to turn on or turn off in response to a user input or a signal from one of the sensor(s)  218 . For instance, a first sensor of the sensor(s)  218  may monitor a temperature of a motor of the fan  210  (such as motor  114 ), a second sensor of the sensor(s)  218  may monitor a current or voltage draw of the motor, a third sensor of the sensor(s)  218  may monitor a volumetric flow rate of the filtered air or of airfield of filtered air  214 , and/or a fourth sensor of the sensor(s)  218  may monitor a filter status of the main filter  204  and/or the rack filter  206 . The controller  216  may receive data from the sensor(s)  218  and determine (based on arbitrarily complex conditions, generally referred to as “error conditions” indicating “errors”) to issue alerts (such as replace filter(s)) or turn on or off the fan  210 . 
     As shown in  FIG.  2 B , the sensors  218  may be a kill switch and the outlet  212  may include a grate  219 . The grate  219  may have one or more portions that interact with the sensors  218  when the grate  219  is placed on the outlet  212  so the sensors  218  may detect whether the grate  219  is on the outlet  212 . In this way, when the sensors  218  do not detect the grate  219  is on the outlet  212 , the controller  216  may receive data from the sensors  218  indicating that there is no grate  219  on the outlet  212  and the controller  216  may turn off the fan  210  or cut off power to the fan  210 . When the sensors  218  detect the grate  219  is on the outlet  212 , the controller may receive data from the sensors  218  indicating that the grate is on the outlet  212  and the controller may turn on the fan  210  or send power to the fan  210 . During operation of the airfield generator  200 , removal of the grate can result in stoppage of the fan  210 , such as due to a hardwired electrical connection or a command from the controller  216 . 
     Moreover, the controller  216  may control the sanitization system  220  to perform additional air sanitization. For instance, the controller  216  may periodically (such as every set period of time) or continuously, cause the sanitization system  220  to perform air sanitization. The sanitization system  220  may be a UV sterilization system within a sealed enclosure of the airfield generator  200 . For instance, the sanitization system  220  may include one or more UV sterilization systems, and the one or more UV sterilization systems may be in the at least one cavity  208 , adjacent to the fan  210 , adjacent to the main filter  204 , and/or adjacent to the rack filter  206  to perform air sanitization in addition to the main filter and the rack filter. One of skill the art would recognize that the one or more UV sterilization systems may direct UV light to one or several of the at least one cavity  208 , the fan  210 , the main filter  204 , and the rack filter  206  at a same time, therefore reducing cost while ensuring filtered environmental air (or unfiltered portion of environment air when the main filter or polygonal filter is not included) is sanitized. 
     Generally, the controller  216  may have a user interface. The user interface may display information to users (e.g., status, data, etc.) of the airfield generator  200  and receive user inputs to control operations of the airfield generator  200  or multiple airfield generators  200 . One of skill in the art would recognize that the controller  216  may be a computer, micro-controller, etc. that executes software using a memory (storing data and instructions on a non-transitory compute readable medium) and a processor to execute the instructions to perform the various operations described herein. 
     B. Example Control Process 
       FIG.  3    depicts a flowchart illustrating a process  300  of controlling an airfield generator in accordance with aspects of this disclosure. For instance, the airfield generator may be a part of the airfield system  100  or  200 , discussed above. The operations of the process  300  may be performed by a controller, such as controller  216 . As depicted in  FIG.  3   , the operations of the process  300  may start by receiving an instruction to turn on (Block  302 ). For instance, the controller may receive a user input or sensor signal indicating an instruction to turn on. 
     The controller may then proceed to cause a motor of a fan to generate an airfield out of an outlet (Block  304 ). For instance, the controller may transmit an instruction to the motor  114  to turn on and cause impellers  706  to rotate at an RPM to thereby draw environmental air  112  and  118  through various filters, such as the rack filter  802  and main filter of the main filter housing  110 , compress the filtered are, and output the airfield via the outlet  104 . 
     The controller may then proceed to monitor sensors and control a sanitization system (Block  306 ). For instance, the controller may monitor the sensor(s)  218  to determine whether errors conditions are satisfied or not and control the UV sterilization systems to perform additional sterilization (on filtered or unfiltered air when the main filter or the triangular filter is not included). 
     The controller may then proceed to, if an error is detected, issue an alert and/or turn off (Block  308 ). For instance, the controller may determine an error condition is satisfied based on sensor data and determine whether to issue an alert or turn off based on policies. For instance, if an error condition is not considered dangerous but preferred to be resolved (e.g., replace filters), the controller may issue an alert. On the other hand, if a motor temperature or an absence of the grate  219  (or some arbitrary complex conditional) indicates a dangerous circumstance, the controller may determine an instruction to turn off the motor. 
     The controller may then proceed to, responsive to an instruction to turn off, cause the motor of the fan to cease generating the airfield out of outlet (Block  310 ). For instance, the controller may receive a user input to turn off or determine a dangerous condition (and thereby determine an instruction to turn off), and send an instruction to the motor to turn off. 
     C. Example Subsystems 
       FIGS.  4 A- 4 E,  5 A- 5 B,  6 A- 6 C,  7 ,  8 A- 8 D, and  9 A- 9 D  depict subsystems of airfield systems  100 ,  200 , or  300  in accordance with aspects of this disclosure. For ease of reference, the following description will refer to features of airfield system  100 , but one of skill in the art would recognize that the features are applicable to airfield systems  200  or  300  as well. 
       FIG.  4 A  depicts the first portion of environmental air  112 , the second portion of environmental air  118  (on one lateral side), and the airfield  106 A of the airfield system  100 , without the structure  102 . Generally, the volumetric flow rate of the first portion of environmental air  112  and the second portion of environmental air  118  (from both lateral sides) may correspond to the volumetric flow rate of the airfield  106 A. Moreover, due to the relative differences in inlet areas of the bypass inlets  116  and the main inlet  426 , the volumetric flow rate of the first portion of environmental air  112  and the volumetric flow rate of the second portion of environmental air  118  (from both lateral sides) may not be substantively similar. Instead, the volumetric flow rate of the first portion of environmental air  112  may be a substantial proportion of the volumetric flow rate of the airfield  106 A. Therefore, the main filter may filter a substantial portion of the volumetric flow rate of the airfield  106 A. As the main filter can be composed of larger filters in both thickness and geometric shape (thereby, increasing surface area for filtering) and more filter layers (generally), the effective MERV level of the main filter may be higher, and in some embodiments substantially higher, than the rack filter. Therefore, the effective MERV level of the airfield system  100  may be greatly improved, with respect to the rack filter  802  alone, as a MERV level of system is based on (upstream versus downstream) rate of filtering at a specific volumetric flow rate. Therefore, in certain embodiments, certain versions of the main filter may be used to achieve a certain MERV level, while certain versions of the main filter, the polygonal filter  502 , or no main filter are used, based on circumstances to achieve different MERV levels. 
       FIG.  4 B  depicts the base  108  without cover  418  (see  FIG.  4 C ) and rack holder  420  (see  FIG.  4 D ). In particular,  FIG.  4 B  illustrates the walls  412 - 416 , a first cavity  406  and a second cavity  408 , in relation to the centrifugal fan  109  to define the sealed interior volume of the base  108 . Generally, the walls  412 - 416  include a first and second side walls  412  and  414 , which may have the bypass inlets  116 , and an end wall  416 . The end wall  416  may be on an opposite end of the base  108  from the centrifugal fan  109 . The first and second side walls  412  and  414  and the end wall  416  may define the structure of the base  108  and ensure sealing to the centrifugal fan  109 , the cover  418 , and the rack holder  420 . The first and second side walls  412  and  414  may ensure sealing between the interior volume along an interface with the shroud of the centrifugal fan  109  and the first and second side walls  412  and  414 . 
     The second cavity  408  may generally correspond to the main inlet  426  and the bypass inlets  116 . For instance, the second cavity may accommodate the rack filter  802  and allow the first portion of environmental air  112  to mix with the second portion of environmental air  118  before they enter the first cavity  406 . The first cavity  406  may be provided to allow for filtered air to enter the first opening in the shroud of the centrifugal fan  109 . Therefore, the first cavity  406  may have a defined gap between the first opening in the shroud and the second cavity  408 . 
       FIG.  4 C  depicts the cover  418  covering the first cavity  406 . The cover  418  may seal the interior volume along an interface with the shroud of the centrifugal fan  109  and the walls  412 - 416 , for instance the first and second side walls  412  and  414 . The cover  418  may extend from the centrifugal fan  109  to the main inlet  426 . 
       FIG.  4 D  depicts the rack holder  420 . The rack holder  420  may include structure  422  and support rails  424 . The structure  422  may support the support rails  424  and ensure sealing around the bypass inlets  116  and the walls  412 - 416 . Generally, the structure  422  and the support rails  424  may define the bypass inlets  116  to accommodate the rack filter  802  and provide structural support to fix the rack filter  802  during operation of the airfield system  100 . 
       FIG.  4 E  depicts the main inlet  426 . In particular, the main inlet  426  may be formed in the structure  422  of the rack holder  420 . Notably, the main inlet  426  may be unblocked by the rack filter  802  within the interior volume. The rack filter  802  may be configured to reduce or avoid vortices in the circular motion from the main inlet  426  to the first opening of the centrifugal fan  109 , such as by the rack filter  802  having a triangular shape. Other shapes are contemplated too, such as rectangular, pentagonal, hexagonal, etc. Moreover, the main inlet  426  may be spaced apart (in the z direction) from the rack filter  802  in accordance with a height of the walls  412 - 416  and the support rails  424 , so as to not interfere with the vortices in the circular motion from the main inlet  426  to the first opening of the centrifugal fan  109 . 
       FIG.  5 A  depicts the polygonal filter  502  covering the main inlet  426 . The polygonal filter  502  may be a triangulated pocket filter or other polygonal shape. The pocket filter may be configured (e.g., by having a triangulated shape) to allow the filter to expand through pockets thereof to increase surface area to increase filtering surface area, versus a fixed shape filter of similar dimensions. The polygonal filter  502  may consist of MERV 13 filter formed into a triangular shape that generally extends along an axial direction of impellers  706 , so that unfiltered air may pass through the filter into the second cavity  408 . 
     The polygonal filter  502  may include a structure  502 B and a triangular filter having axial filter portion(s)  502 A and an end filter portion  502 C. The structure  502 B may provide a rigid exterior portion of the polygonal filter  502  with one or more openings to accommodate the axial filter portion(s)  502 A and the end filter portion(s)  502 C, to thereby filter environmental air passing through the one or more openings. The structure  502 B may be made of cardboard, plastic, metal, or other suitable materials, or combinations thereof. The axial filter portion(s)  502 A and the end filter portion(s)  502 C may be unitary in construction (e.g., a filter formed into a triangular cylinder shape with proximal and terminal ends made of filter material), to seal each of the one or more openings of the polygonal filter  502  and to filter air moving therethrough. In this manner, construction of the filter may be easier (by avoiding internal adhesion for each filter portion to each opening and coordination thereof) but may be more costly as portions of filter not adjacent to the one or more openings may provide only partial filtering efficiency (e.g., as they are adjacent to the structure  502 B). Alternatively, the axial filter portion(s)  502 A and the end filter portion(s)  502 C may be separate pieces of filter fixed to the structure  502 B to seal each of the one or more openings of the polygonal filter  502  and to filter air moving therethrough. In this manner, less filter material may be used, but construction complexity may be increased. 
     In some embodiments, each axial filter portion  502 A may correspond to an axially extending opening on a surface of the structure  502 B of the polygonal filter  502 . The axial filter portion(s)  502 A (and the corresponding openings associated therewith) may form a filtering portion of each face of the polygonal filter  502 . The structure  502 B may form a non-filtering portion of each face of the polygonal filter  502 . Generally, the filtering portion of each face may be smaller, equal to, or larger than a non-filtering portion of each face of the polygonal filter  502 . In particular, a ratio of the filtering portion of each face to the non-filtering portion of each face is equal to or at least about: 30:1, 20:1, 15:1, 10:1, 15:2, 5:1, 5:2, ratios between the aforementioned ratios. As noted above, each axial filter portion  502 A may expand through (e.g., in a radially outward manner) or expand away (e.g., in a radially inward manner) from its respective axially extending opening on the surface of the structure  502 B of the polygonal filter  502 . In this manner, each axial filter portion  502 A may increase an effective filter surface area, to thereby increase filtering capacity polygonal filter  502 . 
     The end filter portion(s)  502 C may correspond to proximal and terminal open ends of the polygonal filter  502 . The end filter portion  502 C may provide additional filtering surface area for the polygonal filter  502 , as environmental air may pass through the end filter portion  502 C separately from the axial filter portion  502 A. 
     In some embodiments, the polygonal filter  502  may include a first side, a second side, and a third side defined by vertices of the polygonal shape, where the first side defines a first filtering surface using a first axial filter portion  502 A, and where the second side defines at least a second filtering surface using a second axial filter portion  502 A. The third side may or may not include additional filter portions and may be designed to face the main inlet  426 . In this manner, the first and second sides may provide at least a certain amount of filtering, while the third side may provide an outlet of the polygonal filter  502  to the main inlet  426 . In the case that the third side also has additional filter portions, the third side may filter the air filtered by the first and second sides before entering the main inlet  426 , thereby increasing an effective MERV rating of the polygonal filter  502  (but also increasing a pressure requirement on the motor  114 ). 
     In some embodiments, the filter  502  may comprise a triangulated pocket filter. The triangulated pocket filter may advantageously provide for a higher efficiency filtration system relative to alternative designs (e.g., a pleated filter system). In some embodiments, the filter  502  may comprise any polygonal shape suitable. For example, the polygonal shape may comprise any one of a triangle, rectangle, pentagon, hexagon, or any of shape as desired. As a particular example, the filter  502  may be an isosceles triangle with the first and second sides having a same length, and the third side having a length corresponding to the main inlet  426  (e.g., to cover the main inlet  426  and provide for engagement mechanisms of filter  502  corresponding to the engagement mechanism on the base  108 ). 
       FIG.  5 B  depicts a main filter  504  covering the main inlet  426  to filter the first portion of environmental air  112 . The main filter  504  may correspond to the main filter housing  110  with one or more filters, discussed above. As depicted in  FIG.  5 B , there are none of the one or more filters included therein, so the interior may be seen. Details of the main filter  504  are discussed below with respect to  FIGS.  6 A- 6 C . 
       FIG.  6 A  depicts an outside of the main filter  504 . As depicted in  600 A, the main filter  504  includes an exterior grate  604 , a pre-screen  606 , and a door  608  with a hinge  610 .  FIG.  6 B  depicts the door  608  opened by the hinge  610 , to expose a support  612  for exterior grate  604 , a first support  613 , a first filter  614 , a second support  615 , and a second filter  616 .  FIG.  6 C  depicts an internal separator screen  618 . 
     The exterior grate  604  may retain the pre-screen  606  and provide a first structural interface with the environment so that pre-screen  606  and other filters are not dislodged. The exterior grate  604  may be metal or plastic and provide a large surface area for first portion of environmental air  112  to pass through the exterior grate  604 . The pre-screen  606  may be a charcoal filter to pre-filter unfiltered air. The pre-screen  606  may filter out larger particulates than the first filter  614  or second filter  616 . 
     The door  608  and the hinge  610  may operate together to hold the exterior grate  604 , the pre-screen  606 , the first filter  614 , and the second filter  616 , in place (when the door is closed), and provide access to the pre-screen  606 , the first filter  614 , and the second filter  616  to replace each of the pre-screen  606 , the first filter  614 , and the second filter  616  as operational use indicates necessary. 
     The support  612  for the exterior grate  604  may support the exterior grate  604  and define an opening of the door  608  when the hinge  610  opens the door  608 . The exterior grate  604  may be retained by structure (see, e.g., lip of main filter  504  above exterior grate  604 ) and supported by the support  612  on at least one side. 
     The first support  613  and the second support  615  may define slots (of predetermined size) to support to first filter  614  and the second filter  616 . For instance, the first support  613  and the second support  615  may be spaced apart by a set distance, such as a standard size of filters for the first filter  614  and the second filter  616 . The first support  613  and the second support  615  may inform a user where to insert the first filter  614  and the second filter  616  and guide the insertion and removal of the first filter  614  and the second filter  616 . The first support  613  and the second support  615  may extend a length of first filter  614  and the second filter  616  from the opening of the door  608  to an opposite side of the main filter  504 , so as support or retain the first filter  614  and the second filter  616 . 
     The first filter  614  and the second filter  616  may be a same or different MERV levels. The first filter  614  and the second filter  616  may be a same or different thicknesses. The first filter  614  and the second filter  616  may be a same lateral size (e.g., a same cross-section), so that the unfiltered air passes through both. Similarly, the pre-screen  606  may be a same lateral size (e.g., a same cross-section), as the first filter  614  and the second filter  616 . For instance, the first filter  614  may be a MERV 8 filter and the second filter  616  may be a MERV 13 filter. One of skill in the art would recognize that various combinations of different MERV levels are possible, such as a MERV 8 and a MERV 8 filter, a MERV 13 and a MERV 13 filter, etc. 
     The internal separator grate  618  may be positioned behind support  612  for the exterior grate  604  to provide a zone of space for pre-filtered air to gather before passing through the first filter  614  and the second filter  616 . The internal separator grate  618  may be metal or plastic and provide a large surface area for first portion of environmental air  112  to pass through the internal separator grate  618 . 
       FIG.  7    depicts noise attenuation materials  702  and  704  of the at least one cavity in view of the impellers  706  of the first opening in the shroud of the centrifugal fan  109 . As discussed above, impellers  706  may compress the air (a mix of filtered and/or unfiltered, depending on configuration) to generate the airfield  106 A out of the outlet  104 . The noise attenuation materials  702  and  704  may line internal surface surfaces of the base  108  in the first cavity  406  and the second cavity  408 . The noise attenuation materials  702  and  704  may comprise rubber that is adhesively bound to portions of the first cavity  406  and the second cavity  408 . 
       FIGS.  8 A- 8 D  depict various rack filters, including a rack filter  802 , a rack filter  804 , a rack filter  806 , and a rack filter  808 . The rack filter  802  may include a triangulated pocket filter to allow the filter to expand through pockets thereof to increase surface area to increase filtering surface area, versus a fixed shape filter of similar dimensions. The rack filter  802  may consist of MERV 13 filter (or other MERV level filter) formed into a triangular shape that generally extends along an axial direction of impellers  706 , so that unfiltered air may pass through the bypass inlets  116  and through the filter into the second cavity  408 . 
     The rack filter  802  may include a structure  802 B and a triangular filter having axial filter portion(s)  802 A filtering environmental air coming into the structure  802 B by end openings  802 C. The structure  802 B may provide a rigid exterior portion of the rack filter  802  with one or more openings to accommodate the axial filter portion(s)  802 A, to thereby filter environmental air passing through the end openings  802 C, through the axial filter portion(s)  802 A, through the one or more openings, and into the second cavity  408 . The structure  802 B may be made of cardboard, plastic, metal, or other suitable materials, or combinations thereof. The axial filter portion(s)  802 A may be unitary in construction (e.g., a filter formed into a triangular cylinder shape with proximal and terminal ends left open to form the end openings  802 C), to seal each of the one or more openings of the rack filter  802  and to filter air moving therethrough. In this manner, construction of the filter may be easier (by avoiding internal adhesion for each filter portion to each opening and coordination thereof) but may be more costly as portions of filter not adjacent to the one or more openings may provide only partial filtering efficiency (e.g., as they are adjacent to the structure  802 B). Alternatively, the axial filter portion(s)  802 A may be separate pieces of filter fixed to the structure  802 B to seal each of the one or more openings of the rack filter  802  and to filter air moving therethrough. In this manner, less filter material may be used, but construction complexity may be increased. In some embodiments, the axial filter portion(s)  802 A may include charcoal, activated charcoal and/or activated carbon. 
     In some embodiments, each axial filter portion  802 A may correspond to an axially extending opening on a surface of the structure  802 B of the rack filter  802 . The axial filter portion(s)  802 A (and the corresponding openings associated therewith) may form a filtering portion of each face of the rack filter  802  that has an opening (e.g., at least one face has an opening, but one, two, or three (or more when the polygonal shape is not a triangle) may also have openings). The structure  802 B may form a non-filtering portion of each face of the rack filter  802  that has an opening. The structure  802 B may also form non-filtering portions on any face that does not have an opening. Generally, the filtering portion of each face of the rack filter  802  may be smaller, equal to, or larger than a non-filtering portion of each face of the rack filter  802 . In particular, a ratio of the filtering portion of each face to the non-filtering portion of each face is equal to or at least about: 30:1, 20:1, 15:1, 10:1, 15:2, 5:1, 5:2, and ratios between the aforementioned ratios. As noted above, each axial filter portion  802 A may expand through (e.g., in a radially outward manner) or expand away (e.g., in a radially inward manner) from its respective axially extending opening on the surface of the structure  802 B of the rack filter  802 . In this manner, each axial filter portion  802 A may increase an effective filter surface area, to thereby increase filtering capacity rack filter  802 . 
     The end openings  802 C may correspond to proximal and terminal open ends of the rack filter  802 . The end openings  802 C may form a part of an air intake of the airfield generator in conjunction with the bypass inlets  116 , so environmental air may pass through the end openings  802 C and then through the axial filter portion(s)  802 A. 
     In some embodiments, the rack filter  802  may include a first side, a second side, and a third side defined by vertices of the polygonal shape. In some embodiments, the first side defines a first filtering surface using a first axial filter portion  802 A, where the second side defines at least a second filtering surface using a second axial filter portion  802 A, and where the third side defines at least a third filtering surface using a third axial filter portion  802 A. In this manner, the first, second, and third sides may provide respective amounts of filtering (based on airflow geometry). In some embodiments, the first side defines a first filtering surface using a first axial filter portion  802 A, where the second side defines at least a second filtering surface using a second axial filter portion  802 A, and the third side defines non-filtering surface (e.g., with no opening in structure  802 B). In this manner, the first and second sides may provide respective amounts of filtering (based on airflow geometry). In some embodiments, the first side defines a first filtering surface using a first axial filter portion  802 A, and the second side and the third side define non-filtering surfaces (e.g., with no opening in structure  802 B). In this manner, the first and second sides may provide respective amounts of filtering (based on airflow geometry). 
     In some embodiments, the rack filter  802  may comprise a triangulated pocket filter. The triangulated pocket filter may advantageously provide for a higher efficiency filtration system relative to alternative designs (e.g., a pleated filter system). In some embodiments, the rack filter  802  may comprise any polygonal shape suitable. For example, the polygonal shape may comprise any one of a triangle, rectangle, pentagon, hexagon, or any of shape as desired. As a particular example, the rack filter  802  may be a right triangle with the first and second sides facing walls  412 - 416 , and the third side forming a hypotenuses therebetween. Generally, as discussed herein, the rack filter  802  may be inserted into the bypass inlets  116  of airfield generator  101  and secured in place to the support rails  424  (e.g., by a foam sealing or other sealing material (not depicted) that surrounds the structure  802 B between the structure  802 B and the structure of the bypass inlets  116 , where the sealing inhibits or prevents air from flowing into the base  108  between the structure  802 B and the structure of the bypass inlets  116  and does not block the end openings  802 C). 
     The rack filter  804 , the rack filter  806 , and the rack filter  808  may be alternative embodiments of the rack filter  802 . For ease of reference, only differences between each will discussed, while similar structural and functional features are applicable to each. 
     The rack filter  804  may include a structure  804 B and a triangular filter having axial filter portion(s)  804 A filtering environmental air coming into the structure  804 B by end openings  804 C. In particular, the axial filter portion(s)  804 A may be more rigid than the axial filter portion(s)  802 A of rack filter  802 , so that each axial filter portion  804 A may expand through (e.g., in a radially outward manner) or expand away (e.g., in a radially inward manner) from its respective axially extending opening on the surface of the structure  802 B to a smaller degree than the axial filter portion(s)  802 A of the rack filter  802 . In this manner, wear and tear (due to movement of the axial filter portion(s)  804 A when pressure changes occur) may be reduced, but an increase in filtering surface may not be as large. 
     The rack filter  806  may include a structure  806 B and a triangular filter having axial filter portion(s)  806 A filtering environmental air coming into the structure  806 B by end openings  806 C. The rack filter  808  may include a structure  808 B and a triangular filter having axial filter portion(s)  808 A filtering environmental air coming into the structure  808 B by end openings  808 C. In particular, both the rack filter  806  and the rack filter  808  may have axial filter portions  806 A,  808 A and respective openings on two filtering surfaces, whereas the rack filters  802 ,  804  may have axial filter portions  802 A,  804 A on a single surface thereof. Additionally, both the rack filter  806  and the rack filter  808  may have multiple (e.g., two or more) axial filter portions  806 A,  808 A on each filtering surface extending axially down the surface separated from each other by portions of structure  806 B,  808 B, whereas rack filter  802 ,  804  may have continuous axial filter portions  802 A,  804 A. 
     Moreover, the rack filters  806 ,  808  may differ in certain respects. For instance, the rack filter  806  and the rack filter  808  may have a same or different number of axial filter portions  806 A,  808 A and respective openings on two filtering surfaces. The sizes (e.g., length and width of openings of the number of axial filter portions  806 A,  808 A) may be a same width or different. The separation spacing between the openings of the number of axial filter portions  806 A,  808 A may be a same separation spacing or different. 
       FIGS.  9 A- 9 J  depict components of a thermal control system, such as a cooling system  902 , for airfield generators. For instance, the airfield system  100 ,  200 ,  300 , in any of the embodiments disclosed herein, may comprise the cooling system  902  to dissipate any heat being output from one or more components of the system and/or to reduce a temperature of one or more components. As described above the bypass inlets  116  may draw air over the motor  114  and/or draw hot air away from the motor  114 , thereby cooling the motor. 
     A schematic overview of the cooling system  902  is shown in  FIG.  9 J . The system can include one or more heat exchanges (also called heat exchangers). In some instances, the cooling system  902  may comprise a first heat exchange  904  (as illustrated in  FIG.  9 A- 9 C ), a pump  908  (as illustrated in in  FIGS.  9 E- 9 H ), and a second heat exchange  910  (as illustrated in  FIG.  91   ). The first heat exchange  904  may be positioned at least partially around the motor  114  to function as a heat sink, so that heat from the motor  114  may be transferred to a coolant of the cooling system  902 . The pump  908  may cause coolant within the cooling system  902  to circulate between the first heat exchange  904  and the second heat exchange  910 . The second heat exchange  910  may be positioned, for example, in the first cavity  406  (as shown in  FIG.  9 J ) to transfer heat from the coolant of the cooling system  902  to filtered air as it enters the first opening in the shroud of the centrifugal fan  109 . 
     In some embodiments, the first heat exchange  904  may have a first inlet portion  904 A, a first outlet portion  904 B, and a first heat transfer portion  904 C connecting the first inlet portion  904 A and the first outlet portion  904 B. The first inlet portion  904 A may be connected to the pump  908  to receive accelerated coolant that was cooled by the second heat exchange  910 . The first outlet portion  904 B may be connected to the second heat exchange  910  to thereby provide heated coolant. The first heat transfer portion  904 C may be a coil wound around (in a first direction (e.g., clockwise) or a second direction (e.g., counterclockwise)) an outside surface of the motor  114  one or more times (e.g., a plurality of times successively along an axially direction of the motor  114 ), so that heat from the motor  114  may be transferred to the coolant passing through the heat transfer portion  904 C. 
     As shown in  FIGS.  9 B and  9 C , the first heat transfer portion  904 C may be separated from the outside surface of the motor  114  by a distance  904 D so the motor  114  can vibrate without contacting the first heat transfer portion  904 C. The distance  904 D can be an air gap and/or void. The first heat transfer portion  904 C may be coupled to the base  108  so the first heat transfer portion  904 C does not contact the outside surface of the motor  114 . 
     In some embodiments, the first heat transfer portion  904 C can include an interior screen  904 C- 1 , coil  904 C- 2 , a first cover  904 C- 3 , and a second cover  904 C- 4 . The interior screen  904 C- 1  may be a thin sheet of material between the motor  114  and the coil  904 C- 2  and may increase the heat transfer from the motor  114  to the coil  904 -C 2 . The interior screen  904 C- 1  may include copper, aluminum, and/or any other material suitable for heat exchange. 
     The coil  904 C- 2  may be connected to the first inlet portion  904 A and the first outlet portion  904 B and may be wound around the interior screen  904 C- 2  one or more times. The coil  904 C- 2  may be tubing and may transport coolant around the motor  114  from the first inlet portion  904 A to the first outlet portion  904 B. As the coolant passes through the coil  904 C- 2  the coolant may draw heat away from the motor  114  and transport the heat away from the motor  114 . 
     The first cover  904 C- 3  may be wrapped around the outside of the coil  904 C- 2  and may keep heat from the motor  114  near the coil  904 C- 2  and away from the motor  114  to increase or maximize an amount of heat the coolant can transport away from the motor  114 . The first cover  904 C- 3  may include aluminum, cooper, and/or any other material that may keep heat near the coil  904 C- 2 . 
     The second cover  904 C- 4  may be a thin sheet of material wrapped around the first cover  904 C- 3 . The second cover  904 C- 4  may be coupled to the first cover  904 C- 3  via a magnet or other securement mechanism. The magnet may be a magnet just strong enough to couple the second cover  904 C- 4  to the first cover  904 -C 3  such that the magnet does not affect the motor  114 . The second cover  904 -C 4  may be an insulator designed to keep heat from escaping outside of the first cover  904 -C 3 . The second cover  904 -C 4  may include Teflon or any other suitable insulating material. 
     The second heat exchange  910  may have a second inlet portion  910 A, a second outlet portion  910 B, and a second heat transfer portion  910 C connecting the second inlet portion  910 A and the second outlet portion  910 B. The second inlet portion  910 A may be connected to the first heat exchange  904  (e.g., the first outlet portion  904 B) to receive heated coolant that was heated by the first heat exchange  904 . The second outlet portion  910 B may be connected to the pump  908  to thereby provide cooled coolant to the pump. The second heat transfer portion  910 C may traverse the first cavity one or more times. For instance, the second heat transfer portion  910 C may traverse the first cavity one time, two times, three times, or generally, a plurality of times. In this manner, the second heat transfer portion  910 C may transfer heat from the coolant to filtered air as it enters the first opening in the shroud of the centrifugal fan  109 . In some embodiments, the second heat exchange  910  may also have a plurality of protrusions  910 C. The plurality of protrusions  910 C of may increase a surface area of the second heat exchange  910 , to increase heat transference from the coolant to the filter air. For instance, the plurality of protrusions  910 C may be fins to interact with the filtered air without substantially constricting airflow into the first opening in the shroud of the centrifugal fan  109 . 
     The pump  908  may have a third inlet portion  908 A, a third outlet portion  908 B, an impeller  908 C, and an actuator system  908 D. The third inlet portion  908 A may be connected to the second outlet portion  910 B of the second heat exchange  910  to receive cooled coolant from the second heat exchange  910 . The third outlet portion  908 B may be connected to the first inlet portion  904 A of the first heat exchange  904  to provide accelerated, cooled coolant to the first heat exchange  904 . The impeller  908 C may accelerate the coolant received by the third inlet portion  908 A in accordance with the actuator system  908 D. 
     The actuator system  908 D may cause the impeller  908 C to rotate to thereby accelerate the coolant. For instance, the actuator system  908 D may be an inductive coil (e.g., a 120 volt alternating current coil) that is placed adjacent (e.g., substantially aligned with and near to) a magnet  908 C- 1  of the pump  908 . The magnet  908 C- 1  may be attached by a spindle  908 C- 2  (e.g., made of plastic) to the impeller  908 C, to thereby cause the impeller  908 C to rotate in accordance with rotation of the magnet. The inductive coil may cause the magnet  908 C- 1  to rotate in accordance with electricity being applied to the inductive coil. In this manner, the coolant circuit (e.g., sequentially through each of the pump  908 , the first heat exchange  904 , the second heat exchange  910 , and back to the pump  908 ) may be sealed from external actuation. The impeller  908 C may be located within a coolant housing  908 E within a path of the coolant. 
     In some embodiments, the coolant may be driven by a heat engine effect (e.g., thermodynamic gradient causing circulation). In various systems, the impeller  908 C and the actuator system  908 D may be omitted if the motor  114  is regulated to avoid outputting substantial heat. 
     Alternatively, the actuator system  908 D may be selectively activated to induce the motion of the impeller  908 C if the motor  114  is not currently outputting substantial heat. For instance, the controller  216  may monitor a temperature of the motor  114  (or an indication thereof, such as current drawn thereby) and control the actuator system  908 D to reduce circulation time, to thereby increase heat transference. Alternatively, the actuator system  904 D may be constantly activated (when the generator  101  is turned on), as the heat transference away the motor  114  may be necessary to regulate the temperature thereof. In this case, the controller  216  may be used to constantly activate the actuator system  904 D, or the actuator system  904 D may be directly hardwired to an electricity source of the generator  101  without the controller  216  controlling the actuator system  904 D. 
     In other embodiments, the first heat exchange  904  may instead have a different configuration. For instance, as illustrated in  FIG.  9 D , the first heat exchange  904  instead be a third heat exchange  906 . The third heat exchange  906  may include a fourth inlet portion  906 A, a fourth outlet portion  906 B, and a third heat exchange portion  906 C. The fourth inlet portion  906 A may correspond to the first inlet portion  904 A of the first heat exchange  904 , as described above. The fourth outlet portion  906 B may correspond to the first outlet portion  904 B of the first heat exchange  904 , as described above. The third heat exchange portion  906 C may be a coil wound around an outside surface of the motor  114 , so that heat from the motor  114  may be transferred to the coolant passing through the heat transfer portion  906 C. 
     The third heat exchange portion  906 C may include a plurality radial portions  906 C- 1 , a plurality of axial portions  906 C- 2 , and a plurality of circumferential portions  906 C- 3 . Each axial portion  906 C- 2  may extend from a proximal end portion of the motor  114  to a terminal end portion of the motor  114 . Each radial portion  906 C- 1  may extend radially outward then extend radially inward while extending circumferentially about a circumference defined substantially by the outer surface of the motor  114 . Each circumferential portions  906 C- 3  may extend circumferentially about the circumference while extending in a first axial direction then in a second axial direction opposite the first axial direction. For instance, each circumferential portions  906 C- 3  may connect two axial portions  906 C- 2  at the proximal end portion of the motor  114 , while each radial portion  906 C- 1  may connect two axial portions  906 C- 2  at the terminal end portion of the motor  114 . 
     The third heat exchange  906  may include a plurality of struts  906 D. Each strut  906 D may extend between adjacent portions of the third heat exchange  906  to increase heat transference between the motor  114  and the coolant. For instance, some struts  906 D may extend circumferentially about the circumference between two or more axial portions  906 C- 2 . Other struts  906 D may extend circumferentially about the circumference between end portions of a circumferential portion  906 C- 3  or a radial portion  906 C- 1 . 
     Generally, the coolant may be any suitable fluid to transfer heat. For instance, the coolant may be a non-hydrous fluid. The coolant may be non-toxic. The coolant may have a boiling point above temperatures the motor  114  may achieve. The first heat exchange  904  second heat exchange  910  and/or third heat exchange  906  may be any appropriate material, such as copper, aluminum, etc. 
     Therefore, the cooling system  902  may capture heat from the motor  114  (e.g., in an enclosed environment) and increase efficiency and safety of the airfield generator  101 . For instance, when the airfield generator  101  is placed in confined parameters (such as under counters or podiums), the heat from the motor  114  may be transferred to the filtered air (which is at ambient temperatures) and distributed away from the system in the airfield  106 A generated by the airfield generator  101 . 
     D. Air Flow Path 
       FIGS.  10 A and  10 B  depict an air flow path of airfield systems of the disclosure. With reference to  FIG.  10 A , a first portion of environmental air  1012  may be drawn into a main filter housing  1010  through a main inlet  1026 . The first portion of environmental air  1012  may be drawn through one or more filters  614 ,  616  (shown in  FIG.  6 B ) to filter the first portion of environmental air  1012  to make a first portion of filtered air  1014 . The first portion of filtered air  1014  may be drawn through a main outlet  1028  out of the main filter housing  1010 . 
     With reference to  FIG.  10 B , the first portion of filtered air  1014  from the main outlet  1028  may be drawn through a secondary inlet  1030  into a base  1008 . The base  1008  may include a rack filter  1016 . A second portion of environmental air  1013  may be drawn into the base  1008  through one or more bypass inlets  116  (shown in  FIGS.  1 D and  1 E ) and through a rack filter  1016 . The rack filter  1016  may be one or more of the rack filters  802 - 808 . The rack filter  1016  may filter the second portion of environmental air  1013  to make a second portion of filtered air  1015 . The second portion of filtered air  1015  may exit the rack filter  1016  through a first side  1020 , a second side  1022 , and a third side  1024 . The second portion of filtered air  1015  that exits the rack filter  1016  through the second side  1022  and the third side  1024  may be drawn through a back portion  1019  of the base  1008 . The second portion of filtered air  1015  that passes through the back portion  1019  may make an airflow of an airfield  1006  laminar. The second portion of filtered air  1015  and the first portion of filtered air  1014  may combine into a filtered air flow  1026 . The filtered air flow  1026  may be drawn into a fan housing  1028  and forced through an outlet  1030  by fan  1029  to make the airfield  1006 . The outlet may be generally vertical and/or upwardly facing (e.g., in a directional generally perpendicular to and/or away from the floor). 
     The first portion of environmental air  1012 , the second portion of environmental air  1013  from a first of the one or more bypass inlets  116 , and the second portion of environmental air  1013  from a second of the one or more bypass inlets  116  may each have different flow rates. The airfield  1006  may have a flow rate higher than the first portion of environmental air  1012 , the second portion of environmental air  1013  from the first of the one or more bypass inlets  116 , and/or the second portion of environmental air  1013  from the second of the one or more bypass inlets  116 . For example, the first portion of environmental air  1012  may have a flow rate of less than or equal to about 230 ft/min, the second portion of environmental air  1013  from the first of the one or more bypass inlets  116  may have a flow rate of less than or equal to about 630 ft/min, and the second portion of environmental air  1013  from the second of the one or more bypass inlets  116  may have a flow rate of less than or equal to about 550 ft/min and the airfield  1006  may have a flow rate of at least about 900 ft/min. 
     E. Further Aspects 
     Generally, airfield systems of the disclosure, including airfield systems  100 ,  200 , or  300 , may be manufactured and/or assembled. For instance, a method to manufacture the airfield system  100  may include: obtaining a housing, a filter system, a motor of an airfield system, where the filter system is engageable with the housing; obtaining a plurality of filters; assembling the housing with the motor; engaging the filter system with the housing; and inserting the plurality of filters. 
     Moreover, airfield systems of the disclosure, including airfield systems  100 ,  200 , or  300 , may reduce the incidences of infectious disease transfer. For instance, a method to reduce the incidences of infectious disease transfer may include: receiving an instruction to operate an airfield generator of airfield systems  100 ,  200 , or  300 ; and causing the motor to generate an air flow from an ambient environment surrounding the airfield generator, through the filter system, and out the outlet of the housing, thereby generating an airfield. The infectious diseases may be a common cold, influenza, and/or COVID. The infectious disease may be caused by one or more of a Rhinoviruses, Coronavirus, influenza virus types A, B, C, D,  Streptococcus pneumoniae, Haemophilus influenzae, Moraxella catarrhalis, Staphylococcus aureus , other streptococci species, anaerobic bacteria, or gram negative bacteria. 
     Further, airfield systems of the disclosure, including airfield systems  100 ,  200 , or  300 , may reduce symptoms of allergy. For instance, a method to reduce symptoms of allergy may include: receiving an instruction to operate an airfield generator of airfield systems  100 ,  200 , or  300 ; and causing the motor to generate an air flow from an ambient environment surrounding the airfield generator, through the filter system, and out the outlet of the housing, thereby generating an airfield. The allergy may be a seasonal allergy or a food allergy. 
     Airfield generators, of airfield systems  100 ,  200 , or  300 , may generate the airfield using air from at least one of the first side of the airfield, the second side of the airfield, or both. The airfield generators may reduce particulates sized 0.3 to 1 micron in the air at an efficiency of at least 75%, and particulates sized greater than 1 micron in the air at an efficiency of at least 90%, at a specific cubic feet per minute. The airfield generators may reduce incidences of infectious disease transfer. For instance, the infectious diseases may be a common cold, influenza, and/or COVID. 
     Many other variations than those described herein will be apparent from this disclosure. For example, certain acts, events, or functions of any of the algorithms described herein can be performed in a different sequence, can be added, merged, or left out altogether (for example, not all described acts or events are necessary for the practice of the algorithms). Moreover, acts or events can be performed concurrently, for example, through multi-threaded processing, interrupt processing, or multiple processors or processor cores or on other parallel architectures, rather than sequentially. In addition, different tasks or processes can be performed by different machines and/or computing systems that can function together. 
     It is to be understood that not necessarily all such advantages can be achieved in accordance with any particular example of the examples disclosed herein. Thus, the examples disclosed herein can be embodied or carried out in a manner that achieves or optimizes one advantage or group of advantages as taught herein without necessarily achieving other advantages as may be taught or suggested herein. 
     The various illustrative logical blocks, modules, and algorithm steps described in connection with the examples disclosed herein can be implemented as electronic hardware, computer software, or combinations of both. To clearly illustrate this interchangeability of hardware and software, various illustrative components, blocks, modules, and steps have been described above generally in terms of their functionality. Whether such functionality is implemented as hardware or software depends upon the particular application and design constraints imposed on the overall system. The described functionality can be implemented in varying ways for each particular application, but such implementation decisions should not be interpreted as causing a departure from the scope of the disclosure. 
     The various illustrative logical blocks and modules described in connection with the examples disclosed herein can be implemented or performed by a machine, such as a general purpose processor, a digital signal processor (DSP), an application specific integrated circuit (ASIC), a field programmable gate array (FPGA) or other programmable logic device, discrete gate or transistor logic, discrete hardware components, or any combination thereof designed to perform the functions described herein. A general purpose processor can be a microprocessor, but in the alternative, the processor can be a controller, microcontroller, or state machine, combinations of the same, or the like. A processor can include electrical circuitry or digital logic circuitry configured to process computer-executable instructions. In another example, a processor can include an FPGA or other programmable device that performs logic operations without processing computer-executable instructions. A processor can also be implemented as a combination of computing devices, for example, a combination of a DSP and a microprocessor, a plurality of microprocessors, one or more microprocessors in conjunction with a DSP core, or any other such configuration. A computing environment can include any type of computer system, including, but not limited to, a computer system based on a microprocessor, a mainframe computer, a digital signal processor, a portable computing device, a device controller, or a computational engine within an appliance, to name a few. 
     The steps of a method, process, or algorithm described in connection with the examples disclosed herein can be embodied directly in hardware, in a software module stored in one or more memory devices and executed by one or more processors, or in a combination of the two. A software module can reside in RAM memory, flash memory, ROM memory, EPROM memory, EEPROM memory, registers, hard disk, a removable disk, a CD-ROM, or any other form of non-transitory computer-readable storage medium, media, or physical computer storage known in the art. An example storage medium can be coupled to the processor such that the processor can read information from, and write information to, the storage medium. In the alternative, the storage medium can be integral to the processor. The storage medium can be volatile or nonvolatile. The processor and the storage medium can reside in an ASIC. 
     The apparatuses and methods described herein may be implemented by one or more computer programs executed by one or more processors. The computer programs include processor-executable instructions that are stored on a non-transitory tangible computer readable medium. The computer programs may also include stored data. Non-limiting examples of the non-transitory tangible computer readable medium are nonvolatile memory, magnetic storage, and optical storage. 
     Some embodiments have been described in connection with the accompanying drawings. The figures are drawn and/or shown to scale, but such scale should not be interpreted as limiting, since dimensions and proportions other than what are shown are contemplated and are within the scope of the disclosed invention. Distances, angles, etc. are merely illustrative and do not necessarily bear an exact relationship to actual dimensions and layout of the devices illustrated. Components can be added, removed, and/or rearranged. Further, the disclosure herein of any particular feature, aspect, method, property, characteristic, quality, attribute, element, or the like in connection with various embodiments can be used in all other embodiments set forth herein. Additionally, any methods described herein may be practiced using any device suitable for performing the recited steps. 
     F. Terminology 
     Terms of orientation used herein, such as “top,” “bottom,” “horizontal,” “vertical,” “longitudinal,” “lateral,” and “end” are used in the context of the illustrated embodiment. However, the present disclosure should not be limited to the illustrated orientation. Indeed, other orientations are possible and are within the scope of this disclosure. Terms relating to circular shapes as used herein, such as diameter or radius, should be understood not to require perfect circular structures, but rather should be applied to any suitable structure with a cross-sectional region that can be measured from side-to-side. Terms relating to shapes generally, such as “circular” or “cylindrical” or “semi-circular” or “semi-cylindrical” or any related or similar terms, are not required to conform strictly to the mathematical definitions of circles or cylinders or other structures, but can encompass structures that are reasonably close approximations. The terms “up” and “down” (and related terms) are with reference to the pull of Earth&#39;s gravity. 
     The terms “approximately,” “about,” and “substantially” as used herein represent an amount close to the stated amount that still performs a desired function or achieves a desired result. For example, in some embodiments, as the context may dictate, the terms “approximately”, “about”, and “substantially” may refer to an amount that is within less than or equal to 10% of the stated amount. The term “generally” as used herein represents a value, amount, or characteristic that predominantly includes or tends toward a particular value, amount, or characteristic. As an example, in certain embodiments, as the context may dictate, the term “generally parallel” can refer to something that departs from exactly parallel by less than or equal to 20 degrees. 
     Conditional language used herein, such as, among others, “can,” “might,” “may,” “for example,” and the like, unless specifically stated otherwise, or otherwise understood within the context as used, is generally intended to convey that certain examples include, while other examples do not include, certain features, elements and/or states. Thus, such conditional language is not generally intended to imply that features, elements and/or states are in any way required for one or more examples or that one or more examples necessarily include logic for deciding, with or without author input or prompting, whether these features, elements and/or states are included or are to be performed in any particular example. The terms “comprising,” “including,” “having,” and the like are synonymous and are used inclusively, in an open-ended fashion, and do not exclude additional elements, features, acts, operations, and so forth. Also, the term “or” is used in its inclusive sense (and not in its exclusive sense) so that when used, for example, to connect a list of elements, the term “or” means one, some, or all of the elements in the list. Further, the term “each,” as used herein, in addition to having its ordinary meaning, can mean any subset of a set of elements to which the term “each” is applied. 
     Disjunctive language such as the phrase “at least one of X, Y, or Z,” unless specifically stated otherwise, is otherwise understood with the context as used in general to present that an item, term, etc., may be either X, Y, or Z, or any combination thereof (for example, X, Y, and/or Z). Thus, such disjunctive language is not generally intended to, and should not, imply that certain examples require at least one of X, at least one of Y, or at least one of Z to each be present. 
     Unless otherwise explicitly stated, articles such as “a” or “an” should generally be interpreted to include one or more described items. Accordingly, phrases such as “a device configured to” are intended to include one or more recited devices. Such one or more recited devices can also be collectively configured to carry out the stated recitations. For example, “a processor configured to carry out recitations A, B and C” can include a first processor configured to carry out recitation A working in conjunction with a second processor configured to carry out recitations B and C. 
     G. Summary 
     Various embodiments and examples of airfield systems, devices, and methods have been disclosed. Although the systems, devices, and methods have been disclosed in the context of those embodiments and examples, and the above detailed description has shown, described, and pointed out novel features as applied to various examples, it will be understood that various omissions, substitutions, and changes in the form and details of the disclosed technology can be made without departing from the spirit of the disclosure. As will be recognized, the embodiments described herein can be embodied within a form that does not provide all of the features and benefits set forth herein, as some features can be used or practiced separately from others. This disclosure expressly contemplates that various features and aspects of the disclosed embodiments can be combined with, or substituted for, one another. Accordingly, the scope of this disclosure should not be limited by the particular disclosed embodiments described above, but should be determined only by a fair reading of the claims that follow.