阅读说明：本技术 用于推进器反馈环位置检测的系统和方法 (System and method for propeller feedback loop position detection ) 是由 J.E.马龙 I.法雷尔 于 2019-06-27 设计创作，主要内容包括：提供了一种用于确定飞行器发动机的推进器的反馈环的位置的系统和方法。反馈环联接到推进器以与推进器一起旋转并且随着叶片角的调节而沿纵向轴线移位。接合构件配置成接合反馈环并且随着反馈环的移位而沿基本上平行于纵向轴线的纵向方向移位。传感器包括联接到发动机的第一构件和联接到接合构件的第二构件。当接合构件移位时,第二构件可沿纵向方向相对于第一构件移动。传感器产生指示第二构件相对于第一构件的纵向位置的信号。控制器从而传感器信号确定反馈环的轴向位置。(A system and method for determining a position of a feedback loop of a propeller of an aircraft engine is provided. The feedback loop is coupled to the propeller to rotate with the propeller and to displace along the longitudinal axis as the blade angle is adjusted. The engagement member is configured to engage the feedback loop and displace in a longitudinal direction substantially parallel to the longitudinal axis with displacement of the feedback loop. The sensor includes a first member coupled to the engine and a second member coupled to the engagement member. When the engagement member is displaced, the second member is movable in the longitudinal direction relative to the first member. The sensor generates a signal indicative of a longitudinal position of the second member relative to the first member. The controller determines the axial position of the feedback loop from the sensor signal.)

1. A feedback loop position detection system for a propeller of an aircraft engine, the propeller being rotatable about a longitudinal axis and having an adjustable blade angle, the system comprising:

a feedback loop coupled to the impeller to rotate with the impeller and to displace along the longitudinal axis as the blade angle is adjusted;

an engagement member configured to engage the feedback loop and displace in a longitudinal direction substantially parallel to the longitudinal axis with displacement of the feedback loop;

a sensor including a first member coupled to the aircraft engine and a second member coupled to the engagement member, the first member being stationary and the second member being movable relative to the first member in the longitudinal direction upon displacement of the engagement member, the sensor being configured to generate a sensor signal indicative of a longitudinal position of the second member relative to the first member; and

a controller configured to receive the sensor signal and determine an axial position of the feedback loop along the longitudinal axis based on a longitudinal position of the second member relative to the first member.

2. The system of claim 1, wherein the feedback loop has a channel formed around a circumferential portion thereof.

3. The system of claim 2, wherein the engagement member is configured to be retained in the channel.

4. The system of claim 3, wherein the channel is U-shaped and the engagement member is a block.

5. The system of any one of claims 1 to 4, wherein the sensor is a linear variable differential transformer, the first member comprises a plurality of solenoid coils, and the second member comprises a ferromagnetic core.

6. The system of any one of claims 1 to 5, wherein the first member is secured to a gearbox of the aircraft engine.

7. The system of any one of claims 1-6, wherein the sensor is configured to generate a sensor signal indicative of a longitudinal displacement of the second member relative to a reference position of the first member.

8. An aircraft engine comprising:

an impeller rotatable about a longitudinal axis and having blades with adjustable blade angles;

a feedback loop coupled to the impeller to rotate with the impeller and to displace along the longitudinal axis as the blade angle is adjusted;

an engagement member configured to engage the feedback loop and displace in a longitudinal direction substantially parallel to the longitudinal axis with displacement of the feedback loop;

a sensor including a first member coupled to the aircraft engine and a second member coupled to the engagement member, the first member being stationary and the second member being movable relative to the first member in the longitudinal direction upon displacement of the engagement member, the sensor being configured to generate a sensor signal indicative of a longitudinal position of the second member relative to the first member; and

a controller configured to receive the sensor signal and determine an axial position of the feedback loop along the longitudinal axis based on a longitudinal position of the second member relative to the first member.

9. The engine of claim 8, wherein the feedback loop has a channel formed around a circumferential portion thereof.

10. The engine of claim 9, wherein the engagement member is configured to be retained in the channel.

11. The engine of claim 10, wherein the channel is U-shaped and the engagement member is a block.

12. An engine according to any of claims 8 to 11, wherein the sensor is a linear variable differential transformer, the first member comprises a plurality of solenoid coils, and the second member comprises a ferromagnetic core.

13. An engine according to any of claims 8 to 12, wherein the first member is fixed to a gearbox of the aircraft engine.

14. An engine according to any of claims 8 to 13, wherein the sensor is configured to generate a sensor signal indicative of a longitudinal displacement of the second member relative to a reference position of the first member.

15. A method for determining an axial position of a feedback loop of a propeller of an aircraft engine, the propeller being rotatable about a longitudinal axis and having an adjustable blade angle, the method comprising:

displacing a movable sensor member relative to a stationary sensor member, the stationary sensor member being coupled to the aircraft engine, and the movable sensor member being displaceable relative to the stationary sensor member in a longitudinal direction substantially parallel to the longitudinal axis when the feedback loop is displaced along the longitudinal axis;

receiving a sensor signal indicative of a longitudinal position of the movable sensor member relative to the stationary sensor member; and

determining an axial position of the feedback loop along the longitudinal axis based on a longitudinal position of the movable sensor member relative to the stationary sensor member as obtained from the sensor signal.

16. The method of claim 15, wherein the sensor signal is indicative of a longitudinal displacement of the movable sensor member relative to a reference position of the stationary sensor member.

17. The method of claim 16, wherein the axial position of the feedback loop is determined based on a longitudinal displacement of the movable sensor member relative to a reference position of the stationary sensor member.

18. The method of any one of claims 15 to 18, wherein displacing the movable sensor member relative to the stationary sensor member comprises: displacing the movable sensor member relative to a reference position of the stationary sensor member, the movable sensor member comprising a ferromagnetic core of a linear variable differential transformer, the stationary sensor member comprising a plurality of solenoid coils of the linear variable differential transformer.

Technical Field

The present application relates generally to propeller feedback systems for aircraft engines and, more particularly, to systems and methods for detecting feedback loop position.

Background

Some aircraft engines have propellers with variable pitch, referred to as propeller blade (or beta) angle. In such engines, precise control of the beta angle is important for proper engine operation. For example, control of the beta angle may allow the blade angle to be controlled according to a desired engine power set point. The accurate measurement of the blade angle also ensures that the propeller is not inadvertently commanded to transition to a low beta angle or an inverted beta angle that would result in a potentially serious fault condition of the aircraft.

Various methods may be used to measure blade angle. One such method involves the use of a feedback loop mounted for rotation with the impeller and axially movable as the blade angle is adjusted. In particular, the blade angle may be obtained from measuring the axial displacement of the feedback loop. However, existing devices that measure this displacement have disadvantages, including their susceptibility to magnetic noise.

Accordingly, there is a need for a system and method for determining the position of a feedback loop of a mover.

Disclosure of Invention

According to one aspect, a feedback loop position detection system for a propeller of an aircraft engine is provided. The propeller is rotatable about a longitudinal axis and has an adjustable blade angle. The system comprises: a feedback loop coupled to the propeller to rotate with the propeller and to displace along the longitudinal axis as the blade angle is adjusted; an engagement member configured to engage the feedback loop and displace in a longitudinal direction substantially parallel to the longitudinal axis with displacement of the feedback loop; a sensor including a first member coupled to the aircraft engine and a second member coupled to the engagement member, the first member being fixed and the second member being movable in the longitudinal direction relative to the first member upon displacement of the engagement member, the sensor being configured to generate a sensor signal indicative of a longitudinal position of the second member relative to the first member; a controller configured to receive the sensor signal and determine an axial position of the feedback loop along the longitudinal axis based on a longitudinal position of the second member relative to the first member.

In some embodiments, the feedback ring has a channel formed around a circumferential portion thereof.

In some embodiments, the engagement member is configured to be retained in the channel.

In some embodiments, the channel is U-shaped and the engagement member is a block.

In some embodiments, the sensor is a linear variable differential transformer, the first member comprises a plurality of solenoid coils and the second member comprises a ferromagnetic core.

In some embodiments, the first component is secured to a gearbox of an aircraft engine.

In some embodiments, the sensor is configured to generate a sensor signal indicative of a longitudinal displacement of the second member relative to a reference position of the first member.

According to one aspect, an aircraft engine is provided. An aircraft engine comprising: an impeller rotatable about a longitudinal axis and having blades with adjustable blade angles; a feedback loop coupled to the impeller to rotate with the impeller and to displace along the longitudinal axis as the blade angle is adjusted; an engagement member configured to engage the feedback loop and displace in a longitudinal direction substantially parallel to the longitudinal axis with displacement of the feedback loop; a sensor including a first member coupled to the aircraft engine and a second member coupled to the engagement member, the first member being fixed and the second member being movable in the longitudinal direction relative to the first member upon displacement of the engagement member, the sensor being configured to generate a sensor signal indicative of a longitudinal position of the second member relative to the first member; and a controller configured to receive the sensor signal and determine an axial position of the feedback loop along the longitudinal axis based on a longitudinal position of the second member relative to the first member.

In some embodiments, the feedback ring has a channel formed around a circumferential portion thereof.

In some embodiments, the engagement member is configured to be retained in the channel.

In some embodiments, the channel is U-shaped and the engagement member is a block.

In some embodiments, the sensor is a linear variable differential transformer, the first member comprises a plurality of solenoid coils and the second member comprises a ferromagnetic core.

In some embodiments, the first component is secured to a gearbox of an aircraft engine.

In some embodiments, the sensor is configured to generate a sensor signal indicative of a longitudinal displacement of the second member relative to a reference position of the first member.

According to one aspect, a method for determining an axial position of a feedback loop of a propeller of an aircraft engine. The propeller is rotatable about a longitudinal axis and has an adjustable blade angle. The method comprises the following steps: displacing a movable sensor member relative to a stationary sensor member, the stationary sensor member being coupled to the aircraft engine, and the movable sensor member being displaceable relative to the stationary sensor member in a longitudinal direction substantially parallel to the longitudinal axis when the feedback loop is displaced along the longitudinal axis; receiving a sensor signal indicative of a longitudinal position of the movable sensor member relative to the stationary sensor member; and determining an axial position of the feedback loop along the longitudinal axis based on the longitudinal position of the movable sensor member relative to the fixed sensor member as obtained from the sensor signal.

In some embodiments, the sensor signal is indicative of a longitudinal displacement of the movable sensor member relative to a reference position of the stationary sensor member.

In some embodiments, the axial position of the feedback loop is determined based on a longitudinal displacement of the movable sensor member relative to a reference position of the stationary sensor member.

In some embodiments, displacing the movable sensor member relative to the stationary sensor member comprises: displacing a movable sensor member relative to a reference position of a stationary sensor member, the movable sensor member comprising a ferromagnetic core of a linear variable differential transformer, the stationary sensor member comprising a plurality of solenoid coils of the linear variable differential transformer.

Drawings

Referring now to the drawings wherein:

FIG. 1 is a schematic cross-sectional view of a gas turbine engine;

FIG. 2 is a schematic cross-sectional illustration of an impeller assembly including a reduction gearbox in accordance with an illustrative embodiment;

FIG. 3 is a schematic illustration of a thruster assembly including a feedback loop in accordance with an illustrative embodiment;

FIG. 4A is a schematic illustration of a thruster assembly that includes the reduction gearbox of FIG. 2, the feedback loop of FIG. 3, and a sensor for measuring the position of the feedback loop, in accordance with an illustrative embodiment;

4B, 4C and 4D are schematic diagrams illustrating the longitudinal movement of the feedback loop and sensor of FIG. 4A;

FIG. 5 is a flowchart of a method for determining an axial position of a feedback loop in accordance with an illustrative embodiment; and

fig. 6 is a block diagram of an example computing system for implementing the method of fig. 5, according to an embodiment.

Detailed Description

FIG. 1 illustrates a gas turbine engine 10 of the type generally configured for subsonic flight, including an inlet 12 through which ambient air is propelled 12; a compressor section 14 for pressurizing air; a combustor 16 in which compressed air is mixed with fuel and ignited for generating an annular flow of hot combustion gases; and a turbine section 18 for extracting energy from the combustion gases. Turbine section 18 illustratively includes a compressor turbine 20 that drives compressor components and accessories, and at least one power or free turbine 22 that is independent of compressor turbine 20 and rotationally drives a rotor shaft 24 about a longitudinal propeller shaft axis a through a reduction gearbox 26. The hot gases may then be exhausted through an exhaust stub 28. The gas generator of engine 10 illustratively includes a compressor section 14, a combustor 16, and a turbine section 18. A rotor 30 in the form of a propeller through which ambient air is propelled is carried in a propeller hub 32. The rotor 30 may, for example, comprise a propeller of a fixed wing aircraft or a main (or tail) rotor of a rotary wing aircraft, such as a helicopter. Rotor 30 may include a plurality of circumferentially arranged blades connected to and extending radially from a hub or any suitable device. The blades may also rotate about their own radial axis through a number of blade angles that may be varied to achieve modes of operation such as feathering, full reverse, and forward thrust.

As depicted in fig. 2, the rotor 30 is part of an impeller assembly 36. The rotor 30 is mounted to the propeller shaft 38 by a mounting flange 40. The propeller shaft 38 is received in the reduction gearbox 26. Reduction gearbox 26 receives power from input shaft 44, and input shaft 44 rotates and drives propeller shaft 38 through gear train 46. The propeller shaft 38 and the rotor 30 rotate about a longitudinal propeller axis a. As used herein, reference to a longitudinal direction refers to a direction substantially parallel to the longitudinal thruster axis a. Gear train 46 may reduce the angular velocity such that rotor 30 rotates at a lower speed than input shaft 44. As depicted, the gear train 46 includes two sets of reduction gears. However, the gear train 46 may have any number of reduction gears. Alternatively or additionally, gear train 46 may include one or more planetary gear sets. Reduction gearbox 26 has a housing 48 with a forward wall 50. The propeller shaft 38 is received through an opening in the front wall 50 and is carried by a bearing 52, the bearing 52 fixing the longitudinal position of the drive shaft 38 relative to the housing 48. The reduction gearbox 26 may vary depending on the actual implementation.

As depicted in fig. 3, the impeller 30 includes a plurality of angularly arranged blades 110, each blade 110 being rotatable about a radially extending axis R by a plurality of adjustable blade angles, the blade angle being the angle between a chord line of the impeller blade portion (i.e. a line drawn between the leading and trailing edges of the blade) and a plane perpendicular to the impeller axis of rotation. The propeller 30 may be a reverse propeller 30 having a variety of modes of operation, such as feathering, full reverse, and forward thrust. In some modes of operation, such as feathering, the blade angle is positive. The propeller 30 may be operated in a reverse mode, wherein the blade angle is negative.

The feedback loop 104 is supported for rotation with the impeller 30, the impeller 30 rotating about the longitudinal axis a. The feedback loop 104 is annular and may be referred to as a beta loop or a beta feedback loop. The feedback ring 104 is also supported for longitudinal sliding movement along the longitudinal axis a (e.g., by support members such as a series of circumferentially spaced beta feedback rods 106 extending along the longitudinal axis a). A compression spring 108 surrounds the end of each rod 106. The feedback loop 104 is mounted to be displaced in the longitudinal direction when the beta angle of the propeller blades is adjusted. In particular, adjustment of the beta angle causes corresponding axial movement of the stem 106, and thus the feedback loop 104, substantially parallel to the axis a. Conversely, adjustment of the beta angle in a first direction moves the feedback loop 104 forward (e.g., toward the propeller 30), and adjustment of the beta angle in an opposite direction moves the feedback loop 104 rearward (e.g., away from the propeller 30). In an example, the stem 106 and feedback loop 104 move to a maximum forward position when the blade 110 is at its minimum (or most negative) beta angle, and the stem 106 and feedback loop 104 move to a maximum rearward position when the blade 110 is at its maximum (or most positive) beta angle. It will be apparent that in other embodiments, this orientation may be reversed. The feedback loop 104 may be used to provide angular blade (or beta) position feedback from the axial position of the feedback loop 104 along the axis a.

With additional reference to fig. 4A, a sensor 200 is used to determine the axial position of the feedback loop 104. The sensor 200 includes a first member 202 and a second member 204, both of which extend in a longitudinal direction. The first member 202 is illustratively fixed, and the second member 204 is displaceable in the longitudinal direction and movable relative to the first member 202. The first member 202 is coupled to the engine 10 in any suitable manner. In the illustrated embodiment, the first member 202 is fixed to the gear case 26. The sensor 200 is configured such that the second member 204 is movable in a longitudinal direction relative to the first member 202 when the feedback loop 104 is moved along the longitudinal axis a. For example, the first member 202 may comprise a tube and the second member 204 may comprise an arm (e.g., a rod, a shaft, a bar, etc.). The arm may be configured to be received in the tube and displaceable in a longitudinal direction, into and out of the tube, when the feedback loop 104 is displaced along the axis a.

The sensor 200 generates a signal indicative of the longitudinal position of the second member 204 relative to the first member 202. Thus, the signal may be indicative of a longitudinal displacement of the second member 204 relative to a reference position of the first member 202. The reference position may be any reference position. When the position of the second member 204 is aligned with any reference position of the first member 202, the signal generated by the sensor 200 indicates no displacement. As the second member 204 moves from the first position to the second position, the sensor 200 generates a signal indicative of the second position, and thus the displacement of the second member 204 relative to the reference position of the first member 202, in response to the displacement of the feedback loop 104 along the longitudinal axis a. It should be understood that the second member 204 may be axially displaced in the longitudinal direction so as to be positioned in a plurality of positions other than the first and second positions.

The second member 204 is coupled to an engagement member 210, the engagement member 210 configured to engage the feedback loop 104. Second member 204 may be coupled to engagement member 210 by any suitable mechanism. For example, in the illustrated embodiment, fasteners 212 are used to couple second member 204 to engaging member 210. The fasteners 212 may be pins, screws, bolts, and the like.

According to an embodiment, the feedback ring 104 has formed a channel 220 around a circumferential portion thereof, the channel 220 being configured to retain the engagement member 210. In the illustrated embodiment, the channel 220 is U-shaped. However, the configuration of the channels 220 may vary depending on the actual implementation. The engagement member 210 is a ring engagement member that is configured to move with the feedback ring 104 along the longitudinal axis a, and the engagement member 210 remains in the channel 220 as the feedback ring 104 rotates. The engagement member 210 may be made of any suitable material(s). In some embodiments, the engagement member 210 is a block. According to a specific and non-limiting example of embodiment, the block is made of carbon.

Computing device 400 is connected to sensor 200 for receiving signals generated by sensor 200. The computing device 400 may be referred to as a controller. The computing device 400 is configured to determine the axial position of the feedback loop from the signal generated by the sensor 200. As described elsewhere in this document, the sensor signal indicates the position of the second member 204 relative to the first member 202. Thus, the axial position of the feedback loop 104 along the longitudinal axis a may be determined from the sensor signal. For example, when the second member 204 is at the first position and aligned with the reference position of the first member 202 (i.e., there is no displacement of the second member 204 relative to the reference position of the first member 202), this corresponds to a first axial position of the feedback loop 104. When the second member 204 is at a second position corresponding to a given displacement of the second member 204 relative to the reference position of the first member 202, this corresponds to a second axial position of the feedback loop. Thus, the relationship between the displacement of the second member 204 relative to the reference position of the first member 202 may be used to determine the axial position of the feedback loop. For example, the axial position of the feedback loop may be determined from the displacement of the second member 204 relative to the reference position of the first member 202 using a look-up table, formula, equation, or the like.

The position of the feedback loop 104 may be determined based on known geometries of the engine and/or the various components described herein. For example, the position of the sensor 200 relative to a thruster face reference position (e.g. the position defined by the axis R in fig. 3) may be used to provide a constant value (e.g. the distance between the thruster face reference position and the sensor 200). The measured displacement of the second member 204 relative to the reference position of the first member 202 may be added to the constant value to determine the position of the feedback loop 104. In some embodiments, when there is a repeatable starting position of the feedback loop, the relative movement may be used to determine the position of the feedback loop 104. The given axial position of the feedback loop corresponds to a given vane angle, and thus the vane angle may be determined from the axial position of the feedback loop 104 by the computing device 400. The configuration of computing device 400 is described in further detail elsewhere in this document.

In some embodiments, the sensor 200 is a Linear Variable Differential Transformer (LVDT). First member 202 may include three solenoid coils and second member 204 may include a cylindrical ferromagnetic core. Three solenoid coils may be placed around the tube. The core may be attached to an arm (e.g., a rod, a shaft, a bar, etc.), and the arm may be coupled to the engagement member 210. The three solenoid coils include a center coil, which is a primary coil, and two outer coils, which are top and bottom secondary coils. The core is configured to slide along an axis a and is configured to move into and out of a tube around which the three solenoid coils are wound. The alternating current drives the primary coils and induces a voltage in each secondary coil that is proportional to the length of the core associated with the secondary coil. As the core moves, the association of the primary coil with the two secondary coils changes and causes the induced voltage to change. In this embodiment, the signal generated by the sensor 200 is the output voltage, which is the difference between the top secondary voltage and the bottom secondary voltage. The output voltage varies depending on the position of the second member 204 relative to the first member 202. For example, the value of the output voltage may vary linearly with the amount of variation in the axial displacement of the second member 204 relative to the reference position of the first member 202. Thus, a given value of the output voltage may correspond to a given axial position of the feedback loop 104.

Referring to fig. 4B, 4C, and 4D, examples illustrate longitudinal movement of the feedback loop 104 and the second member 204 of the sensor 200. In this example, the actuator 109 engages with the piston assembly 111 to adjust the beta angle of the blade. Specifically, the piston assembly 111 moves back and forth in the longitudinal direction and causes rotation of the vane 110 through sliding engagement with the actuator 109. In the depicted embodiment, forward motion of the piston assembly 111 decreases the beta angle of the blade 110, and rearward motion increases the beta angle. However, in other embodiments, the situation may be reversed. When the piston assembly 111 adjusts the beta angle, the piston assembly 111 also engages the rod 106. As shown in fig. 4B, during a portion of the forward movement of the piston assembly 111, the piston assembly 111 bears against a stop 113 mounted to the rod 106, pulling the rod 106 and feedback ring 104 in a forward direction (as indicated by arrow 291) and compressing the spring 108. The second member 204 also moves forward as the feedback loop 104 moves forward. As shown in fig. 4C, when the piston assembly 111 is moved in a rearward direction (as indicated by arrow 292), the spring 108 pushes the rod 106 and the feedback wheel 104 rearward. The second member 204 also moves rearward as the feedback loop 104 moves rearward. In the depicted embodiment, the feedback wheel 104 reaches a maximum rearward position (the position shown in FIG. 4C) before the piston assembly 111 reaches its maximum rearward position. After the feedback loop 104 reaches the maximum rearward position, the piston assembly 111 moves out of contact with the stop 113, as shown in fig. 4D, after which further rearward movement of the piston assembly 111 does not cause movement of the feedback loop 104. Other suitable configurations for adjusting the beta angle and causing corresponding longitudinal movement of the feedback wheel 104 will be apparent to the skilled person.

Referring to fig. 5, a flow chart illustrating an example method 300 for determining the axial position of the feedback loop 104 is shown. Although method 300 is described herein with reference to engine 10, this is for exemplary purposes. The method 300 may be applied to any suitable engine. At step 302, a movable sensor member (also referred to herein as second member 204) is displaced relative to a stationary sensor member (also referred to herein as first member 202). The stationary sensor member 202 is coupled to the aircraft engine 10, and when the feedback loop 104 is displaced along the longitudinal axis a, the movable sensor member 204 may be displaced relative to the stationary sensor member 204 along a longitudinal direction substantially parallel to the longitudinal axis a. A sensor signal indicative of the longitudinal position of the movable sensor member relative to the fixed sensor member is generated at the sensor 200. At step 304, a sensor signal indicative of a position of the movable sensor member 204 relative to the stationary sensor member 202 is received. The sensor signal may be as described elsewhere in this document. At step 304, the axial position of the feedback loop 104 is determined based on the longitudinal position of the movable sensor member 204 relative to the fixed sensor member 202. The determination of the axial position of the feedback loop 104 may be determined as described elsewhere in this document. The axial position of the feedback loop 104 may also be referred to as the longitudinal position of the feedback loop 104. The propeller blade angle may then be determined from the axial position of the feedback loop 104. The determined propeller blade angle may be output to an aircraft computer, for example, to display the propeller blade angle on an aircraft or cockpit display. The determined propeller blade angle may be used by the controller 400 (or another engine controller and/or aircraft computer) for various engine and/or aircraft controls. For example, the determined propeller blade angle may be used to synchronize phasing to adjust the blade angle of each propeller of a plurality of engines of a multi-engine propeller driven aircraft. For example, the engine controller(s) and/or the aircraft computer(s) may adjust the propeller blade angle of each engine based on the determined propeller blade angles of the plurality of engines.

In some embodiments, the sensor signal is indicative of a longitudinal displacement of the movable sensor member 204 relative to a reference position of the stationary sensor member 202. In some embodiments, the axial position of the feedback loop 104 is determined based on a longitudinal displacement of the movable sensor member 204 relative to a reference position of the stationary sensor member 202. In some embodiments, displacing the movable sensor member 204 relative to the stationary sensor 202 comprises: the movable sensor member 204 (which includes a ferromagnetic core of a linear variable differential transformer) is displaced relative to a reference position of the stationary sensor member 202 (which includes a plurality of solenoid coils of a linear variable differential transformer).

Referring to fig. 6, the method 300 may be implemented, at least in part, using a computing device 400 that includes a processing unit 412 and a memory 414, the memory 414 having stored therein computer-executable instructions 416. The processing unit 412 may include any suitable device configured to implement the system such that the instructions 416, when executed by the computing device 400 or other programmable apparatus, may cause the functions/acts/steps of the method 300 as described herein to be performed. Processing unit 412 may include, for example, any type of general purpose microprocessor or microcontroller, a Digital Signal Processing (DSP) processor, a Central Processing Unit (CPU), an integrated circuit, a Field Programmable Gate Array (FPGA), a reconfigurable processor, other suitably programmed or programmable logic circuitry, or any combination thereof.

Memory 414 may include any suitable known or otherwise machine-readable storage medium. Memory 414 may include a non-transitory computer-readable storage medium, such as, but not limited to, an electronic, magnetic, optical, electromagnetic, infrared, or semiconductor system, apparatus, or device, or any suitable combination of the foregoing. The memory 414 may comprise any type of suitable combination of computer memory, either internal or external to the device, such as Random Access Memory (RAM), Read Only Memory (ROM), Compact Disc Read Only Memory (CDROM), electro-optic memory, magneto-optic memory, Erasable Programmable Read Only Memory (EPROM), and Electrically Erasable Programmable Read Only Memory (EEPROM), ferroelectric RAM (fram), and the like. Memory 414 may comprise any storage device (e.g., an apparatus) suitable for retrievably storing machine-readable instructions 416 executable by processing unit 412. In some embodiments, the computing device 400 may be implemented as part of a Full Authority Digital Engine Control (FADEC) or other similar device, including an Electronic Engine Control (EEC), an Engine Control Unit (ECU), or the like.

The methods and systems for determining the axial position of a feedback loop described herein may be implemented in a high level procedural or object oriented programming or scripting language, or a combination thereof, to communicate with or facilitate the operation of a computer system, such as computing device 400. Alternatively, the method and system for determining the axial position of the feedback loop may be implemented in assembly or machine language. The language may be a compiled or interpreted language. Program code for implementing the method and system for determining the axial position of the feedback loop may be stored on a storage medium or device, such as a ROM, magnetic disk, optical disk, flash drive, or any other suitable storage medium or device. The program code can be read by a general-purpose or special-purpose programmable computer for configuring and operating the computer when the storage medium or device is read by the computer to perform the procedures described herein. Embodiments of the method and system for determining an axial position of a feedback loop may also be considered to be embodied by a non-transitory computer-readable storage medium having a computer program stored thereon. The computer program may comprise computer readable instructions which cause a computer or in some embodiments the processing unit 412 of the computing device 400 to operate in a specific and predefined manner to perform the functions described herein.

Computer-executable instructions may take many forms, including program modules, executed by one or more computers or other devices. Generally, program modules include routines, programs, objects, components, data structures, etc. that perform particular tasks or implement particular abstract data types. Typically, the functionality of the program modules may be combined or distributed as desired in various embodiments.

The above description is intended to be exemplary only, and those skilled in the art will recognize that changes may be made to the embodiments described without departing from the scope of the invention disclosed. Other modifications, which are within the scope of this invention, will be apparent to those of skill in the art upon reviewing this disclosure.

Various aspects of the methods and systems for determining the axial position of a feedback loop may be used alone, in combination, or in a variety of arrangements not specifically discussed in the embodiments described in the foregoing and is therefore not limited in its application to the details and arrangement of components set forth in the foregoing description or illustrated in the drawings. For example, aspects described in one embodiment may be combined in any manner with aspects described in other embodiments. While particular embodiments have been shown and described, it will be obvious to those skilled in the art that changes and modifications may be made without departing from the invention in its broader aspects. The scope of the following claims should not be limited by the embodiments set forth by way of example, but should be accorded the broadest reasonable interpretation consistent with the description as a whole.