Patent Publication Number: US-2021180466-A1

Title: Lidar based fod detection for gas-turbine engines

Description:
FIELD 
     This disclosure relates generally to gas turbine engines, and more particularly to a foreign object debris (FOD) detection system for gas-turbine engines. 
     BACKGROUND 
     Gas turbine engines typically include a fan section to drive inflowing air, a compressor section to pressurize inflowing air, a combustor section to burn a fuel in the presence of the pressurized air, and a turbine section to extract energy from the resulting combustion gases. The fan section may include a plurality of fan blades coupled to a fan hub. Forward of the fan section typically includes an inlet. During operation of a gas turbine engine, foreign object debris (FOD) may enter the inlet and/or enter a gas turbine engine. 
     SUMMARY 
     A gas turbine engine is disclosed herein. The gas turbine engine may comprise a nacelle at least partially defining a boundary of an inlet of the gas turbine engine; a fan section disposed aft of the inlet; and a foreign object debris (FOD) detection system mounted to a radially inner surface of the nacelle; the FOD detection system comprising a light detection and ranging (LiDAR) sensor assembly configured to scan a pre-determined volume within the inlet. 
     In various embodiments, the gas turbine engine may further comprise an FOD detection processor electrically coupled to the LiDAR sensor assembly, the FOD detection processor configured to transfer a control signal to increase a resolution in a local area of a tracking zone in response to detecting FOD in the local area. The LiDAR sensor assembly may comprise a single transceiver configured to scan the pre-determined volume within the inlet. The LiDAR sensor assembly may comprise a plurality of transceivers, wherein each transceiver in the plurality of transceivers is fixed, the plurality of transceivers configured to scan the pre-determined volume. The plurality of transceivers may be disposed in an array. The LiDAR sensor assembly may further comprise a plurality of transmitters and a receiver, each transmitter in the plurality of transmitters configured to emit a pulsed beam sequentially following an adjacent transmitter in the plurality of transmitters. The plurality of transmitters may be disposed in an array. The LiDAR sensor assembly may further comprise a plurality of receivers and a transmitter, wherein each receiver is configured to detect a reflection from a pre-determined direction. The plurality of receivers may be disposed in an array. 
     A gas turbine engine is disclosed herein. The gas turbine engine may comprise: an engine core; an inlet disposed forward of the engine core, the inlet comprising a centerbody; and a foreign object debris (FOD) detection system mounted to the centerbody; the FOD detection system comprising a first light detection and ranging (LiDAR) sensor assembly configured to scan a first pre-determined volume within the inlet, the first pre-determined volume defining at least one of a first volume forward of the centerbody and a second volume radially outward of the centerbody. 
     In various embodiments, the gas turbine engine may further comprise a second LiDAR sensor assembly coupled to the centerbody. The first pre-determined volume may be the first volume. The second LiDAR sensor assembly may be configured to scan a second pre-determined volume, and the second pre-determined volume may be the second volume. The first LiDAR sensor assembly may be configured to detect and track FOD during operation of the gas turbine engine. The gas turbine engine may further comprise an FOD detection processor electrically coupled to the first LiDAR sensor assembly, and the first LiDAR sensor assembly may comprise a plurality of transceivers. The FOD detection processor may be configured to increase a first resolution of a first portion of transceivers in the plurality of transceivers in response to a transceiver in the plurality of transceivers detecting the FOD. The FOD detection processor may be configured to decrease a second resolution of a second portion of transceivers in the plurality of transceivers in response to the transceiver in the plurality of transceivers detecting the FOD. The second portion of transceivers may be different than the first portion of transceivers. The gas turbine engine may further comprise an FOD detection processor electrically coupled to the first LiDAR sensor assembly. The first LiDAR sensor assembly may comprise a plurality of transmitters and a receiver. The FOD detection processor may be configured to increase a first resolution of a first portion of transmitters in the plurality of transmitters in response to a transmitter in the plurality of transmitters detecting the FOD. The FOD detection processor may be configured to decrease a second resolution of a second portion of transmitters in the plurality of transmitters in response to the transmitter in the plurality of transmitters detecting the FOD. The second portion of transmitters may be different than the first portion of transmitters. 
     A method of using a foreign object debris (FOD) detection system for a gas turbine engine is disclosed herein. The method may comprise: detecting FOD in an inlet of the gas turbine engine; increasing a first resolution of a first portion of transmitters or receivers in a plurality of transmitters or transceivers; and tracking the FOD through a pre-determined volume defined by the plurality of transmitters or transceivers. 
     In various embodiments, the method may further comprise decreasing a second resolution of a second portion of transmitters or transceivers in the plurality of transmitters or transceivers. The second portion of transmitters or transceivers being different than the first portion of transmitters or transceivers. 
     The foregoing features and elements may be combined in various combinations without exclusivity, unless expressly indicated otherwise. These features and elements as well as the operation thereof will become more apparent in light of the following description and the accompanying drawings. It should be understood, however, the following description and drawings are intended to be exemplary in nature and non-limiting. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1A  illustrates a cross-section view of a gas turbine engine, in accordance with various embodiments; 
         FIG. 1B  illustrates a perspective view of a front portion of a gas turbine engine, in accordance with various embodiments; 
         FIG. 2A  illustrates a cross-section, schematic view of a gas turbine engine, in accordance with various embodiments; 
         FIG. 2B  illustrates a cross-section, schematic view of a gas turbine engine during operation, in accordance with various embodiments; 
         FIG. 3A  illustrates a cross-section, schematic view of a gas turbine engine, in accordance with various embodiments; 
         FIG. 3B  illustrates a cross-section, schematic view of a gas turbine engine during operation, in accordance with various embodiments; 
         FIG. 4A  illustrates a cross-section, schematic view of a gas turbine engine, in accordance with various embodiments; 
         FIG. 4B  illustrates a cross-section, schematic view of a gas turbine engine during operation, in accordance with various embodiments; 
         FIG. 5  illustrates a light detection and ranging (LiDAR) sensor assembly, in accordance with various embodiments; 
         FIG. 6  illustrates a light detection and ranging (LiDAR) sensor assembly, in accordance with various embodiments; 
         FIG. 7  illustrates a light detection and ranging (LiDAR) sensor assembly, in accordance with various embodiments; and 
         FIG. 8  illustrates a method of using a foreign object debris (FOD) detection system of a gas turbine engine, in accordance with various embodiments. 
     
    
    
     DETAILED DESCRIPTION 
     The detailed description of exemplary embodiments herein makes reference to the accompanying drawings, which show exemplary embodiments by way of illustration. While these exemplary embodiments are described in sufficient detail to enable those skilled in the art to practice the disclosures, it should be understood that other embodiments may be realized and that logical changes and adaptations in design and construction may be made in accordance with this disclosure and the teachings herein. Thus, the detailed description herein is presented for purposes of illustration only and not of limitation. 
     The scope of the disclosure is defined by the appended claims and their legal equivalents rather than by merely the examples described. For example, the steps recited in any of the method or process descriptions may be executed in any order and are not necessarily limited to the order presented. Furthermore, any reference to singular includes plural embodiments, and any reference to more than one component or step may include a singular embodiment or step. Also, any reference to attached, fixed, coupled, connected or the like may include permanent, removable, temporary, partial, full and/or any other possible attachment option. Additionally, any reference to without contact (or similar phrases) may also include reduced contact or minimal contact. Surface shading lines may be used throughout the figures to denote different parts but not necessarily to denote the same or different materials. 
     As used herein, “electronic communication” means communication of electronic signals with physical coupling (e.g., “electrical communication” or “electrically coupled”) or without physical coupling and via an electromagnetic field (e.g., “inductive communication” or “inductively coupled” or “inductive coupling”). As used herein, “transmit” may include sending electronic data from one system component to another via electronic communication between the components. Additionally, as used herein, “electronic data” may include encompassing information such as commands, queries, files, data for storage, and the like in digital or any other form. 
     As used herein, “aft” refers to the direction associated with the tail (e.g., the back end) of an aircraft, or generally, to the direction of exhaust of the gas turbine. As used herein, “forward” refers to the direction associated with the nose (e.g., the front end) of an aircraft, or generally, to the direction of flight or motion. 
     In various embodiments, and with reference to  FIG. 1A , a gas turbine engine  120  is disclosed. As used herein, “aft” refers to the direction associated with a tail (e.g., the back end) of an aircraft, or generally, to the direction of exhaust of gas turbine engine  120 . As used herein, “forward” refers to the direction associated with a nose (e.g., the front end) of the aircraft, or generally, to the direction of flight or motion. An A-R-C axis has been included throughout the figures to illustrate the axial (A), radial (R) and circumferential (C) directions. For clarity, axial axis A spans parallel to engine central longitudinal axis A-A′. As utilized herein, radially inward refers to the negative R direction towards engine central longitudinal axis A-A′, and radially outward refers to the R direction away from engine central longitudinal axis A-A′. 
     Gas turbine engine  120  may comprise a two-spool turbofan that generally incorporates a fan section  122 , a compressor section  124 , a combustor section  126 , and a turbine section  128 . In operation, fan section  122  may drive air along a bypass flow-path B, while compressor section  124  may further drive air along a core flow-path C for compression and communication into combustor section  126 , before expansion through turbine section  128 .  FIG. 1A  provides a general understanding of the sections in a gas turbine engine, and is not intended to limit the disclosure. The present disclosure may extend to all types of applications and to all types of turbine engines, including, for example, turbojets, turboshafts, and three spool (plus fan) turbofans wherein an intermediate spool includes an intermediate pressure compressor (“IPC”) between a low pressure compressor (“LPC”) and a high pressure compressor (“HPC”), and an intermediate pressure turbine (“IPT”) between the high pressure turbine (“HPT”) and the low pressure turbine (“LPT”). 
     In various embodiments, gas turbine engine  120  may comprise a low speed spool  130  and a high speed spool  132  mounted for rotation about an engine central longitudinal axis A-A′ relative to an engine static structure  136  via one or more bearing systems  138  (shown as, for example, bearing system  138 - 1  and bearing system  138 - 2  in  FIG. 1A ). It should be understood that various bearing systems  138  at various locations may alternatively or additionally be provided, including, for example, bearing system  138 , bearing system  138 - 1 , and/or bearing system  138 - 2 . 
     In various embodiments, low speed spool  130  may comprise an inner shaft  140  that interconnects a fan  142 , a low pressure (or a first) compressor section  144 , and a low pressure (or a second) turbine section  146 . Inner shaft  140  may be connected to fan  142  through a geared architecture  148  that can drive fan  142  at a lower speed than low speed spool  130 . Geared architecture  148  may comprise a gear assembly  160  enclosed within a gear housing  162 . Gear assembly  160  may couple inner shaft  140  to a rotating fan structure. High speed spool  132  may comprise an outer shaft  150  that interconnects a high pressure compressor (“HPC”)  152  (e.g., a second compressor section) and high pressure (or a first) turbine section  154 . A combustor  156  may be located between HPC  152  and high pressure turbine  154 . A mid-turbine frame  157  of engine static structure  136  may be located generally between high pressure turbine  154  and low pressure turbine  146 . Mid-turbine frame  157  may support one or more bearing systems  138  in turbine section  128 . Inner shaft  140  and outer shaft  150  may be concentric and may rotate via bearing systems  138  about engine central longitudinal axis A-A′. As used herein, a “high pressure” compressor and/or turbine may experience a higher pressure than a corresponding “low pressure” compressor and/or turbine. 
     In various embodiments, the air along core airflow C may be compressed by low pressure compressor  144  and HPC  152 , mixed and burned with fuel in combustor  156 , and expanded over high pressure turbine  154  and low pressure turbine  146 . Mid-turbine frame  157  may comprise airfoils  159  located in core airflow path C. Low pressure turbine  146  and high pressure turbine  154  may rotationally drive low speed spool  130  and high speed spool  132 , respectively, in response to the expansion. 
     In various embodiments, gas turbine engine  120  may comprise a high-bypass ratio geared aircraft engine. The bypass ratio of gas turbine engine  120  may also be greater than ten (10:1). Geared architecture  148  may be an epicyclic gear train, such as a star gear system (sun gear in meshing engagement with a plurality of star gears supported by a carrier and in meshing engagement with a ring gear) or other gear system. Geared architecture  148  may have a gear reduction ratio of greater than about 2.3 and low pressure turbine  146  may have a pressure ratio that is greater than about five (5). The diameter of fan  142  may be significantly larger than that of the low pressure compressor section  144 , and the low pressure turbine  146  may have a pressure ratio that is greater than about five (5:1). The pressure ratio of low pressure turbine  146  is measured prior to inlet of low pressure turbine  146  as related to the pressure at the outlet of low pressure turbine  146 . It should be understood, however, that the above parameters are exemplary of various embodiments of a suitable geared architecture engine and that the present disclosure contemplates other turbine engines including direct drive turbofans. 
     The next generation turbofan engines are designed for higher efficiency and use higher pressure ratios and higher temperatures in high pressure compressor  152  than are conventionally experienced. These higher operating temperatures and pressure ratios create operating environments that cause thermal loads that are higher than the thermal loads conventionally experienced, which may shorten the operational life of current components. 
     In various embodiments, and with reference to  FIG. 1B , a perspective view of a front portion of gas turbine engine  120  is depicted in greater detail. Gas turbine engine  120  may comprise a nacelle  101 , fan section  122 , and nose cone  102 . Fan section  122  may comprise a plurality of circumferentially arranged fan blades  121 . Fan platforms  123 , or spacers, may be arranged between adjacent fan blades  121 . Fan blades  121  may be mounted to a fan hub  103  located radially inward of fan platforms  123 . Nose cone  102  may be arranged forward of fan blades  121  to provide an aerodynamic flow path through fan section  122  along with fan platforms  123 . 
     In various embodiments, and with reference to  FIG. 2A , a foreign object debris (FOD) detection system  265  is disclosed. FOD detection system  265  may be configured to track FOD that has entered the inlet of a gas turbine engine. For example, FOD detection system  265  may be used to detect an elevation, azimuth and duration of FOD that has entered the inlet by scanning a pre-determined volume forward of fan blades  121 . The present disclosure may improve FOD detection, and accuracy of FOD size and trajectory during operation of gas turbine engine  120 , allowing for more accurate maintenance and/or inspection schedules of engine blades. Although the present disclosure may make reference to FOD detection systems forward of fan blades  121 , it should be understood by one skilled in the art that the present disclosure extends to any potential FOD detection systems within gas turbine engine  120 , and/or any other suitable engine. 
     In various embodiments, FOD detection system  265  may comprise various components to aid in FOD detection and/or tracking. For example, FOD detection system  265  may comprise a light detection and ranging (LiDAR) sensor assembly  270  and/or a FOD detection processor  290 . FOD detection system  265  may be installed within nacelle  101  of gas turbine engine  120 , as discussed further herein. In that respect, FOD detection system  265  may be coupled to nacelle  101  and may allow for FOD detection and/or tracking during operation of gas turbine engine  120 . In various embodiments, FOD detection system  265  may also be removably inserted within nacelle  101 . 
     In various embodiments, FOD detection system  265  may comprise FOD detection processor  290 . FOD detection processor  290  may be in electronic communication with LiDAR sensor assembly  270 . In various embodiments, FOD detection processor  290  may be integrated into computer systems onboard an aircraft, such as, for example, a full authority digital engine control (FADEC), an engine-indicating and crew-alerting system (EICAS), and/or the like. FOD detection processor  290  may include one or more processors and/or one or more tangible, non-transitory memories and be capable of implementing logic. Each processor can be 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. 
     In various embodiments, FOD detection processor  290  may comprise a processor configured to implement various logical operations in response to execution of instructions, for example, instructions stored on a non-transitory, tangible, computer-readable medium. As used herein, the term “non-transitory” is to be understood to remove only propagating transitory signals per se from the claim scope and does not relinquish rights to all standard computer-readable media that are not only propagating transitory signals per se. Stated another way, the meaning of the term “non-transitory computer-readable medium” and “non-transitory computer-readable storage medium” should be construed to exclude only those types of transitory computer-readable media which were found in In Re Nuijten to fall outside the scope of patentable subject matter under 35 U.S.C. § 101. 
     In various embodiments, FOD detection processor  290  may be configured to control FOD detection system  265 . For example, FOD detection processor  290  may be configured to transfer a control signal to increase a resolution in a local area of a tracking zone in response to detecting FOD in the local area. FOD detection processor  290  may generate and transmit the control signal based on an input received from the LiDAR sensor assembly  270 . The excitation control signal may comprise electronic instructions configured to cause the LiDAR sensor assembly  270  to pulse and/or scan a pre-determined volume in an inlet of the gas-turbine engine, as discussed further herein. The scan may be configured to concentrate on a local volume in response to detection of FOD. In various embodiments, the LiDAR sensor assembly  270  may be configured to sear a beam to various azimuths and elevations, send and receive a returned pulse at each azimuth and elevation (i.e., each grid point). The scan may be achieved via mechanical means, solid state means, or the like. 
     Referring now to  FIG. 2B , a FOD detection system  265  for a gas turbine engine  120  during use is illustrated. In various embodiments, LiDAR sensor assembly  270  is configured to scan a pre-determined volume  320  within an inlet  310  of a gas turbine engine  120 . The inlet  310  may be at least partially defined by nacelle  101 , nose cone  102  and fan blades  121 . In various embodiments, the LiDAR sensor assembly  270  may comprise a transceiver, a transmitter and receiver, or the like. The LiDAR sensor assembly  270  may be configured to rapidly transmit light. The light may be transmitted in various directions and define a pre-determined volume  320  in inlet  310 . The light transmitted from the LiDAR sensor assembly  270  may reflect off a component in the inlet (e.g., the nose cone  102 ) and return to the LiDAR sensor assembly  270 . The LiDAR sensor assembly  270  may be configured to receive the returned light via a transceiver, a receiver, or the like. The LiDAR sensor assembly  270  may be configured to measure the time it takes for the emitted light to travel to the component in the inlet  310  and back. The time may be used to calculate a distance via LiDAR sensor assembly  270 . By scanning throughout pre-determined volume  320  in the inlet  310 , the LiDAR sensor may define a spatial relation of components in the inlet  310  during normal operation of gas turbine engine  120 . In doing so, LiDAR sensor may be configured to identify, detect, and/or track FOD  301  that enters inlet  310  along an FOD path  302 . 
     Referring now to  FIG. 3A , a schematic view of a gas turbine engine  400  including a FOD detection system  465 , in accordance with various embodiments is illustrated. FOD detection system  465  may comprise the LiDAR sensor assembly  270  and FOD detection processor  290 . Gas turbine engine  400  comprises an inlet  410 , an engine core  420 , and an exhaust  430 . In various embodiments, the inlet comprises a centerbody  412  disposed at a forward end of inlet  410 . In various embodiments, LiDAR sensor assembly  270  may be coupled to the centerbody  412  of inlet  410  (e.g., a bifurcated inlet) and directed in the aft direction towards engine core  420 . The LiDAR sensor assembly  270  may be configured to scan a volume aft of centerbody  412 . By mounting the LiDAR sensor assembly  270  to centerbody  412 , the LiDAR sensor assembly  270  may scan an entire volume of or substantially an entire volume of inlet  410  prior to entering engine core  420 . 
     Referring now to  FIG. 3B , an FOD detection system  465  for a gas turbine engine  400  during use is illustrated. In various embodiments, LiDAR sensor assembly  270  is configured to scan a pre-determined volume  415  within an inlet  410  of a gas turbine engine  400 . In various embodiments, the LiDAR sensor assembly  270  may comprise a transceiver, a transmitter and receiver, or the like. The LiDAR sensor assembly  270  may be configured to rapidly transmit light. The light may be transmitted in various directions and define a pre-determined volume  415  in inlet  410 . The light transmitted from the LiDAR sensor assembly  270  may reflect off an inner surface of inlet  410  and/or fan section  422  of engine core  420  and return to the LiDAR sensor assembly  270 . The LiDAR sensor assembly  270  may be configured to receive the returned light via a transceiver, a receiver, or the like. The LiDAR sensor assembly  270  may be configured to measure the time it takes for the emitted light to travel to the inner surface of inlet  410  and/or the fan section  422  and back. The time may be used to calculate a distance via LiDAR sensor assembly  270 . 
     By scanning throughout pre-determined volume  415  in the inlet  410 , the LiDAR sensor assembly  270  may define a spatial relation of inlet  410  in the pre-determined volume  415  during normal operation of gas turbine engine  400 . In doing so, LiDAR sensor assembly  270  may be configured to identify, detect, and/or track FOD  401  that enters inlet  410  along a FOD path  402  and travels through the pre-determined volume  415 . The LiDAR sensor assembly  270  may be configured to target a local area within pre-determined volume  415  of inlet  410  when LiDAR sensor detects FOD  401 . In doing so, LiDAR sensor may more accurately map and/or track FOD  401  as it travels along FOD path  402  and enters engine core  420 . 
     Referring now to  FIG. 4A , a schematic view of a gas turbine engine  500  including a FOD detection system  565 , in accordance with various embodiments is illustrated. FOD detection system  565  may comprise LiDAR sensor assembly  270  and FOD detection processor  290 . Gas turbine engine  500  comprises an inlet  510 , an engine core  520 , and an exhaust  530 . In various embodiments, the inlet comprises a centerbody  512  disposed at a forward end of inlet  510 . In various embodiments, LiDAR sensor assembly  270  may be coupled to the centerbody  512  of inlet  510  and directed RADIALLY outward towards an inner surface of inlet  510 . The LiDAR sensor assembly  270  may be configured to scan a volume radially outward of centerbody  412 . For example, LiDAR sensor may be configured to rotate about centerbody  512 . By mounting the LiDAR sensor assembly  270  to centerbody  412 , LiDAR sensor may scan an entire pre-determined volume  515  in inlet  510  prior to entering engine core  420  and/or ensure any FOD traveling through the inlet  510  is detected. 
     Referring now to  FIG. 4B , a FOD detection system  565  for a gas turbine engine  500  during use is illustrated. In various embodiments, LiDAR sensor assembly  270  is configured to scan a pre-determined volume  515  within an inlet  310  of a gas turbine engine  500 . In various embodiments, the LiDAR sensor assembly  270  may comprise a transceiver, a transmitter and receiver, or the like. The LiDAR sensor assembly  270  may be configured to rapidly transmit light. The light may be transmitted in various directions and define a pre-determined volume  515  in inlet  510 . The light transmitted from the LiDAR sensor assembly  270  may reflect off an inner surface of inlet  510  and return to the LiDAR sensor assembly  270 . The LiDAR sensor assembly  270  may be configured to receive the returned light via a transceiver, a receiver, or the like. The LiDAR sensor assembly  270  may be configured to measure the time it takes for the emitted light to travel to the inner surface of inlet  410  and/or the fan section  422  and back. The time may be used to calculate a distance via LiDAR sensor assembly  270 . 
     By LiDAR sensor assembly  270  scanning throughout pre-determined volume  515  in the inlet  510  and rotating about centerbody  512 , the LiDAR sensor may define a spatial relation of inlet  510  in the pre-determined volume  515  during normal operation of gas turbine engine  400 . In doing so, LiDAR sensor assembly  270  may be configured to identify, detect, and/or track FOD  501  that enters inlet  510  along a FOD path  502  and travels through the pre-determined volume  515 . The LiDAR sensor assembly  270  may be configured to target a local area within pre-determined volume  515  of inlet  510  when LiDAR sensor detects FOD  501 . In doing so, LiDAR sensor may more accurately map and/or track FOD  501  as it travels along FOD path  502  and enters engine core  520 . 
     In various embodiments, a gas turbine engine may comprise a plurality of LiDAR assemblies. The LiDAR sensor assemblies from  FIGS. 2A-4B  may be used in any combination and be within the scope of this disclosure. As such, using a plurality of LiDAR sensor assemblies may allow tracking of FOD from entering the inlet until the FOD reaches the engine core. A LiDAR sensor assembly  270  may be disposed anywhere in inlet  410  and be within the scope of this disclosure. The LiDAR sensor assembly  270  may be configured to track any FOD that enters an inlet of a gas turbine engine as disclosed herein. 
     Referring now to  FIG. 5 , a LiDAR sensor assembly  670 , in accordance with various embodiments, is illustrated. LiDAR sensor assembly  670  comprises a plurality of transceivers  672 . In various embodiments, the plurality of transceivers  672  may be arranged in an array. Each transceiver in the plurality of transceivers  672  may be aimed in a different direction. The plurality of transceivers  672  may be arranged to define a pre-determined volume to be scanned. Each transceiver may be configured to output a pulsed beam. The angle and/or width of each pulsed beam in the plurality of pulsed beams  674  may be defined by a resolution of the respective pulsed beam. In various embodiments, each pulsed beam in the plurality of pulsed beams  674  may have the same resolution. In various embodiments, a corresponding FOD detection processor in a respective FOD detection system may increase a resolution of a first portion of beams in the plurality of pulsed beams  674  and decrease a resolution of a second portion of beams in the plurality of pulsed beams  674  in response to detecting FOD proximate the first portion of beams. In other words, the enhanced resolution of the pulsed beams directed proximate the FOD may more accurately track the FOD as it travels towards an engine core. 
     In various embodiments, each transceiver in the plurality of transceivers  672  are fixed. Each transceiver may scan its respective direction at the same time as an adjacent transceiver, or each transceiver may scan its respective direction sequentially following an adjacent transceiver. In various embodiments, LiDAR sensor assembly  270  in  FIGS. 2A-4B  may be in accordance with LiDAR sensor assembly  670 . 
     Referring now to  FIG. 6 , a LiDAR sensor assembly  770 , in accordance with various embodiments, is illustrated. LiDAR sensor assembly  770  comprises a plurality of transmitters  772  and a receiver  780 . In various embodiments, the plurality of transmitters  772  may be arranged in an array. Each transmitter in the plurality of transmitters  772  may be aimed in a different direction. The plurality of transmitters  772  may be arranged to define a pre-determined volume to be scanned. Each transmitter may be configured to output a pulsed beam. The angle and/or width of each pulsed beam in the plurality of pulsed beams  774  may be defined by a resolution of the respective pulsed beam. In various embodiments, each pulsed beam in the plurality of pulsed beams  774  may have the same resolution. In various embodiments, a corresponding FOD detection processor in a respective FOD detection system may increase a resolution of a first portion of beams in the plurality of pulsed beams  774  and decrease a resolution of a second portion of beams in the plurality of pulsed beams  774  in response to detecting FOD proximate the first portion of beams. In other words, the enhanced resolution of the pulsed beams directed proximate the FOD may more accurately track the FOD as it travels towards an engine core. 
     In various embodiments, each transmitter in the plurality of transmitters  772  are fixed. Each transmitter may scan its respective direction sequentially following an adjacent transceiver. By scanning each transmitter in the plurality of transmitters  772  sequentially, the receiver can correlate the return beam to a respective transmitter in the plurality of transmitters  772 . In various embodiments, LiDAR sensor assembly  270  in  FIGS. 2A-4B  may be in accordance with LiDAR sensor assembly  770 . 
     Referring now to  FIG. 7 , a LiDAR sensor assembly  870 , in accordance with various embodiments, is illustrated. LiDAR sensor assembly  870  comprises a plurality of receivers  880  and a transmitter  872 . In various embodiments, the plurality of receivers  880  may be arranged in an array. Each receiver in the plurality of receivers  880  may be aimed in a different direction. The plurality of receivers  880  may be arranged to cover and/or define a pre-determined volume to be scanned. The transmitter  872  may be configured to output a non-directional pulsed beam  874 . The angle and/or width of the pulsed beam may be defined by a resolution of the respective pulsed beam and configured to provide a return to each receiver in the plurality of receivers  880 . 
     In various embodiments, each receiver in the plurality of receivers  880  and the transmitter  872  are fixed. The transmitter  872  may scan the volume illuminated by the non-directional pulsed beam. Each receiver in the plurality of receivers  880  may be aligned in a pre-defined direction. A scan of the volume of non-directional pulsed beam  874  may be achieved after each pulse. In various embodiments, LiDAR sensor assembly  270  in  FIGS. 2A-4B  may be in accordance with LiDAR sensor assembly  870 . 
     In various embodiments, LiDAR sensor assembly  270  in  FIGS. 2A-4B  may comprise a single transceiver configured to scan a respective predefined volume by scanning in various directions. The various directions of the transceiver may create a grid in the respective predefined volume and detect FOD by determining any changes to the spatial relationships in the predefined volume. 
     Referring now to  FIG. 8 , a method  900  of using a FOD detection system for a gas turbine engine, in accordance with various embodiments, is illustrated. The method comprises detecting foreign object debris (FOD) (step  902 ). The FOD may be detected by a plurality of transmitters or a plurality of transceivers from a LiDAR sensor assembly. The FOD may first be detected by a respective transmitter or transceiver in the plurality of transmitters or the plurality of transceivers. In response to the respective transmitter or transceiver detecting the FOD, a resolution of a first portion of transmitters or transceivers that are adjacent to the respective transmitter or receiver may be increased (step  904 ). 
     The method  900  may further comprise decreasing a resolution of a second portion of transmitters or transceivers (step  906 ). The second portion of transmitters or transceivers are mutually exclusive from the first portion of transmitters or receivers. The method  900  may further comprise tracking the FOD via the first portion of transmitters or transceivers (step  908 ). By increasing the resolution of the transmitters or transceivers that reflect off the FOD, the path of the FOD may more accurately be detected, while maintaining the amount of power consumption of the FOD detection system. 
     Benefits, other advantages, and solutions to problems have been described herein with regard to specific embodiments. Furthermore, the connecting lines shown in the various figures contained herein are intended to represent exemplary functional relationships and/or physical couplings between the various elements. It should be noted that many alternative or additional functional relationships or physical connections may be present in a practical system. However, the benefits, advantages, solutions to problems, and any elements that may cause any benefit, advantage, or solution to occur or become more pronounced are not to be construed as critical, required, or essential features or elements of the disclosure. The scope of the disclosure is accordingly to be limited by nothing other than the appended claims, in which reference to an element in the singular is not intended to mean “one and only one” unless explicitly so stated, but rather “one or more.” 
     Moreover, where a phrase similar to “at least one of A, B, or C” is used in the claims, it is intended that the phrase be interpreted to mean that A alone may be present in an embodiment, B alone may be present in an embodiment, C alone may be present in an embodiment, or that any combination of the elements A, B and C may be present in a single embodiment; for example, A and B, A and C, B and C, or A and B and C. Systems, methods and apparatus are provided herein. In the detailed description herein, references to “one embodiment”, “an embodiment”, “various embodiments”, etc., indicate that the embodiment described may include a particular feature, structure, or characteristic, but every embodiment may not necessarily include the particular feature, structure, or characteristic. Moreover, such phrases are not necessarily referring to the same embodiment. 
     Further, when a particular feature, structure, or characteristic is described in connection with an embodiment, it is submitted that it is within the knowledge of one skilled in the art to affect such feature, structure, or characteristic in connection with other embodiments whether or not explicitly described. After reading the description, it will be apparent to one skilled in the relevant art(s) how to implement the disclosure in alternative embodiments. 
     Furthermore, no element, component, or method step in the present disclosure is intended to be dedicated to the public regardless of whether the element, component, or method step is explicitly recited in the claims. No claim element herein is to be construed under the provisions of 35 U.S.C. 112(f), unless the element is expressly recited using the phrase “means for.” As used herein, the terms “comprises”, “comprising”, or any other variation thereof, are intended to cover a non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements does not include only those elements but may include other elements not expressly listed or inherent to such process, method, article, or apparatus.