GB2587416A

GB2587416A - Landing gear position sensing

Info

Publication number: GB2587416A
Application number: GB1914050.8A
Authority: GB
Inventors: Wilson Fraser
Original assignee: Airbus Operations Ltd
Current assignee: Airbus Operations Ltd
Priority date: 2019-09-30
Filing date: 2019-09-30
Publication date: 2021-03-31
Also published as: GB201914050D0

Abstract

A landing gear position sensing system 1 comprising a system measuring position of landing gear component(s) 4, e.g. landing gear 7, bay door 12, uplocks 11, 16 or mechanisms 10, 15. An energy receiver(s) 3 (e.g. lidar sensor) receives energy from energy transmitter(s) 2 (e.g. laser or lidar transmitter). Energy characteristic (e.g. wavelength, energy density, travel time from transmission to reception) is indicative of the landing gear component position. Preferably electromagnetic energy spectrum is used, e.g. microwaves, radio waves, infrared, ultraviolet or visible light. Transmitter and receiver may be unitary 6 or mounted separately, moving relative to one another (figure 2). Receiver and transmitter may form a millimetric radar, monitoring positions of all landing gear bay components. Edge detection software may map the undercarriage bay. Leaks, failures, missing components, animals or a person may be detected in the landing gear bay through digital image comparison. Also disclosed an aircraft controller 5 determining first and second statuses of landing gear component(s) based on data received from energy receiver(s), the data indicative of first and second properties of the landing gear component(s). Properties may include position, temperature, structural rigidity and rotational velocity. Statuses may include landing gear position, tyre or brake condition.

Description

LANDING GEAR POSITION SENSING

TECHNICAL FIELD

[0001] The present invention relates to a landing gear position sensing system, a landing gear system, an aircraft controller and a method of operating a controller to determine a status of at least one landing gear component.

BACKGROUND

100021 In some known aircraft, landing gear is held in an extended position when the aircraft is on the ground and is stowed at a retracted position in a landing gear bay once the aircraft has taken off Such stowage of the landing gear helps to reduce aircraft drag and noise and the risk of the landing gear being damaged in flight The landing gear subsequently is extended to the extended position again before the aircraft lands. A landing gear bay door may at least partially cover the landing gear bay when closed, and may be openable to enable movement of the landing gear between the retracted position and the extended position. Movement of the landing gear and the landing gear bay door is typically controlled by a pilot using cockpit flight controls of the aircraft, such as a landing gear control lever.

10003] The landing gear of an aircraft can comprise many moving parts, the positions of which need to be accurately and reliably monitored to ensure that the landing gear is operating correctly (e.g. to determine when the landing gear is fully extended or retracted). Known devices for monitoring the position of a landing gear component utilise proximity sensors with an inductive circuit to determine when the component is in a particular position. In order to monitor all of the components in a landing gear, it has been known to use upwards of thirty such proximity sensors. This large quantity of sensors may make installation and replacement very time consuming. There is desire for a landing gear position sensing system that utilises fewer components while retaining the ability to accurately monitor multiple components.

SUMMARY

100041 A first aspect of the present invention provides a landing gear position sensing system comprising: a position measuring system configured to measure a position of at least one landing gear component, the position measuring system comprising: at least one energy transmitter and at least one energy receiver; wherein the at least one energy receiver is configured to receive energy from the at least one energy transmitter in use, a characteristic of the energy being indicative of the position of the at least one landing gear component.

100051 Optionally, the landing gear position sensing system further comprises a controller configured to: receive information representative of the energy received by the at least one energy receiver; and determine the position of the at least one landing gear component based on the information 100061 Optionally, the at least one energy transmitter and the at least one energy receiver are comprised in a unitary item.

100071 Optionally, the at least one energy transmitter and the at least one energy receiver are mountable in separate discrete positions.

100081 Optionally, the energy is electromagnetic energy.

100091 Optionally, the at least one energy receiver is a lidar sensor and the at least one energy transmitter is a lidar transmitter.

100101 Optionally, the at least one energy transmitter is a laser.

100111 A second aspect of the present invention provides a landing gear system comprising: at least one landing gear component; and a landing gear position sensing system, wherein the landing gear position sensing system comprises: a position measuring system configured to measure a position of at least one landing gear component, the position measuring system comprising: at least one energy transmitter and at least one energy receiver; wherein the at least one energy receiver is configured to receive energy from the at least one energy transmitter in use, a characteristic of the energy being indicative of the position of the at least one landing gear component.

100121 The landing gear position sensing system of the second aspect of the present invention may comprise any of the above optional features of the landing gear position sensing system of the first aspect of the present invention.

100131 Optionally, at least one of the at least one energy transmitter and the at least one energy receiver is provided on the at least one landing gear component.

100141 Optionally, the at least one energy transmitter is movable relative to the at least one energy receiver.

100151 Optionally, the at least one energy transmitter and the at least one energy receiver are positioned remote from the at least one landing gear component and the at least one landing gear component is movable relative to the at least one energy transmitter and the at least one energy receiver.

100161 Optionally, the at least one landing gear component is at least one of a landing gear, part of a landing gear movement mechanism for moving the landing gear, a landing gear bay door, part of a landing gear bay door movement mechanism for moving the landing gear bay door, and an uplock for retaining a landing gear or a landing gear bay door in position.

100171 A third aspect of the present invention provides an aircraft controller configured to: receive data from at least one energy receiver, the data being indicative of a first and a second property of at least one landing gear component; and determine a first and a second status of the at least one landing gear component on the basis of the data.

100181 Optionally, the first and the second property include at least one of. position, temperature, structural rigidity and rotational velocity.

100191 Optionally, the first and the second status include at least one of landing gear position, tyre condition and brake condition.

100201 A fourth aspect of the present invention provides a method of operating a controller to determine a status of at least one landing gear component, the method comprising: receiving data from at least one energy receiver indicative of the status of the at least one landing gear component; and determining the status of the at least one landing gear component on the basis of the data.

100211 Optionally, the method further comprises providing an indication of the status of the at least one landing gear component to an operator.

100221 A fifth aspect of the present invention provides a non-transitory computer-readable storage medium storing instructions that, if executed by an aircraft controller, cause the aircraft controller to carry out the method according to the fourth aspect of the present invention.

100231 A sixth aspect of the present invention provides an aircraft comprising a landing gear position sensor system according to the first aspect of the present invention, a landing gear system according to the second aspect of the present invention, an aircraft controller according to the third aspect of the present invention or a non-transitory computer-readable storage medium according to the fifth aspect of the present invention.

BRIEF DESCRIPTION OF THE DRAWINGS

[0024] Embodiments of the invention will now be described, by way of example only, with reference to the accompanying drawings, in which: [0025] Figure 1 shows a schematic view of a landing gear system of an example of one embodiment of the invention.

[0026] Figure 2 shows a schematic view of a landing gear system of an example of another embodiment of the invention.

[0027] Figure 3 shows a flow diagram of a method of an example of one embodiment of the invention.

[0028] Figure 4 shows a schematic diagram of an example of a non-transitory computer-readable medium.

[0029] Figure 5 shows a schematic isometric view of an aircraft of an example of one embodiment of the invention.

DETAILED DESCRIPTION

[0030] Figure 1 shows a landing gear system. The landing gear system comprises a plurality of landing gear components, which are described in more detail below, and a landing gear position sensing system. The landing gear position sensing system comprises a position measuring system that is configured to measure a position of at least one landing gear component 4 of the landing gear components. In this embodiment, the landing gear component 4 in question is a landing gear, but in other embodiments it may be any one or more of those mentioned herein. The position measuring system 1 comprises at least one energy transmitter 2 and at least one energy receiver 3. In use, the at least one energy receiver 3 is configured to receive energy from the at least one energy transmitter 2. A characteristic of the energy is indicative of the position of the at least one landing gear component 4. In some embodiments, the characteristic of the energy may include at least one of energy density, wavelength and/or the time from transmission by the transmitter to reception at the receiver.

[0031] As shown in Figure 1, the landing gear system may comprise a landing gear 7 that is movable between a retracted position 8 and an extended position 9, a landing gear movement mechanism 10, an uplock 11 for retaining the landing gear 7 in the retracted position 8, a landing gear bay door 12 that is movable between a closed position 13 and an open position 14, a landing gear bay door movement mechanism 15, and an uplock 16 for retaining the landing gear bay door 12 in the closed position 13. Although not expressly shown in Figure 2, the landing gear 7 may also comprise at least one of a bogie beam, folding links and/or steering components. Each of these landing gear elements listed in this paragraph is an example of a "landing gear component" 4 referred to herein.

[0032] The landing gear bay door 12 is associated with a landing gear bay (not shown). The landing gear bay door 12 at least partially covers the landing gear bay when in the closed position 13. The landing gear 7 is at least partially positioned in the landing gear bay when in the retracted position 8. This way, the landing gear bay door 12 helps to protect the landing gear bay, and the landing gear 7 when stowed in the bay, from debris that might be thrown towards the bay while the aircraft is moving on the ground or in flight. Moreover, the landing gear bay door 12 helps to reduce drag (i.e. create an aerodynamically-cleaner aircraft) when closed, as compared to when the bay is exposed. The landing gear bay door 12 is movable to the open position 14, at which movement of the landing gear 7 between the extended position 9 and the retracted position 8 is permitted.

[0033] The landing gear bay door movement mechanism 15 is for moving the landing gear bay door 12 between the closed position 13 and the open position 14, to permit movement of the landing gear 7 between the extended position 9 and the retracted position 8. The landing gear bay door movement mechanism 15 may be hydraulically-actuated, electro-hydraulically-actuated, electrically-actuated lock, or mechanically-actuated, for example.

[0034] The landing gear bay door uplock 16 is for retaining the landing gear bay door 12 in the closed position 13. In some cases, the landing gear bay door uplock 16 may be omitted. For example, the landing gear bay door 12 may be held in the closed position 13 by the landing gear bay door movement mechanism 15 or by a mechanical linkage. The landing gear bay door movement mechanism 15 may be hydraulically-actuated, electro-hydraulically-actuated, electrically-actuated lock, or mechanically-actuated, for example.

[0035] The landing gear movement mechanism 10 is for moving the landing gear 7 between the extended position 9 and the retracted position 8. The landing gear movement mechanism may be hydraulically-actuated, electro-hydraulically-actuated, electrically-actuated lock, or mechanically-actuated, for example.

[0036] The landing gear uplock 11 is for retaining the landing gear 7 in the retracted position 8. In some cases, the landing gear uplock 11 may be omitted. For example, the landing gear 7 may be held in the retracted position 8 by the landing gear movement mechanism 10 or by a mechanical linkage. The landing gear uplock 11 may be hydraulically-actuated, electro-hydraulically-actuated, electrically-actuated lock, or mechanically-actuated, for example.

[0037] In some embodiments, such as that shown in Figure 1, the landing gear position sensing system 1 further comprises a controller 5. The controller 5 is configured to receive information representative of the energy received by the at least one energy receiver 3 and determine the position of the at least one landing gear component 4 based on the information [0038] As shown in Figure 1, in some embodiments, the at least one energy transmitter 2 and the at least one energy receiver 3 may be comprised in a unitary item 6. Advantageously, this enables simple installation and replacement (if required).

[0039] Figure 2 shows an alternative embodiment of a landing gear system. This alternative embodiment is the same as the system of Figure 1, except for the configuration of the at least one energy transmitter 2 and the at least one energy receiver 3. In Figure 2, the at least one energy transmitter 2 and the at least one energy receiver 3 are mounted in separate discrete positions. More specifically, the at least one energy transmitter 2 is mounted on the landing gear component 4, and the at least one energy receiver 3 is mounted remotely from the landing gear component 4. The locations shown in Figure 2 are one example of the arrangement of the at least one energy transmitter 2 and the at least one energy receiver 3. The at least one energy transmitter 2 and the at least one energy receiver 3 may be positioned the other way around, so that the at least one energy transmitter 2 is mounted remotely from the landing gear component 4 and the at least one energy receiver 3 is mounted on the landing gear component 4, or be positioned in entirely different locations. In some embodiments, the at least one energy transmitter 2 and the at least one energy receiver 3 may be provided on the at least one landing gear 4.

[0040] In some embodiments, the landing gear position sensing system 1 is positioned in an aircraft landing gear bay. In some embodiments, reflective surfaces may be used to enable hard-to-reach components to be monitored. For example, a reflective surface (e.g. a minor) may be used to direct the energy from the at least one energy transmitter 2 around a corner or obstruction and towards a target. The target may be the at least one landing gear component 4 or the at least one energy receiver 3.

[0041] In some embodiments, the at least one energy transmitter 2 is configured to transmit energy towards a target. For example, the at least one energy transmitter 2 may be configured to direct energy towards at least one landing gear component 4 (as shown in Figure 1) or towards the at least one energy receiver 3 (as shown in Figure 2). The at least one energy receiver 3 is configured to receive at least part of the energy transmitted by the at least one energy transmitter 2. The at least one energy receiver 3 may be configured to receive the energy directly from the at least one energy transmitter 2 (as shown in Figure 2) or after reflection from the at least one landing gear component 4 (as shown in Figure 1). The travel time of the energy or differences in energy between the transmitted energy and the received energy may be used to determine the position of the at least one landing gear component 4.

[0042] In some embodiments, the energy may be electromagnetic energy. For example, the energy may be in the spectrum of at least one of microwaves, radio waves, infrared light, visible light or ultraviolet light.

[0043] In some embodiments, microwaves may be used to determine the surface and/or subsurface structural condition of non-metallic components (e.g. plastics or polymeric composites). For example, microwaves may be used to determine the condition of aircraft landing gear tyres and/or aircraft doors (e.g. fuselage doors or landing gear bay doors).

[0044] The at least one energy transmitter 2 and the at least one energy receiver 3 may be any components capable of transmitting or receiving energy. In some embodiments, the at least one energy receiver 3 is a lidar sensor and the at least one energy transmitter 2 is a lidar transmitter. In some embodiments, the at least one energy transmitter 2 is a laser. In one embodiment, the at least one energy receiver 3 and the at least one energy transmitter 2 may form part of a millimetric radar.

[0045] The use of a lidar or millimetric radar may allow a single device to be used to monitor the positions of plural, or all, of the components in a landing gear bay. Lidar measures a distance to a target by illuminating the target with laser light and measuring the reflected light with a sensor. The difference in laser return times and wavelengths can be used to make digital 3D representations of the target. Millimetric radar work in a similar way to lidar, but instead of laser light, use millimetre waves. The wave energy reflected back from a target can be used to contrast a 3D image of the target. As such, a single lidar or millimetric radar may be used to create a 3D representation of substantially all of the landing gear bay. In some embodiments, a multiplicity of devices may be used for redundancy. Advantageously, lidar and/or millimetric radar may have faster response time than a conventional proximity sensor. As such, operations that require the determination of a status of at least one landing gear component 4 may occur faster.

[0046] In some embodiments, the controller 5 may use edge detection software to determine the position and status of the at least one landing gear component 4. For example, if lidar or millimetric radar is used in a landing gear bay, edge detection software may be used to map the landing gear bay and the landing gear components therein. Advantageously, a substantially real-time image of the landing gear bay may be created, from which multiple components and statuses may be monitored at once. Moreover, when edge detection is used to determine a position of the at least one landing gear component 4, it is possible to determine the position at various points of its motion. In contrast, the use of a conventional proximity sensor may only allow the detection of the position of the at least one landing gear component 4 at a single point. Advantageously, edge detection may allow prediction of the dynamic movement of the at least one landing gear component 4, which may be used to increase the efficiency of other processes in an aircraft. For example, this prediction can be used to determine when a landing gear bay door is open enough to begin extending or retracting the landing gear, which may help to reduce the overall time taken to complete the extension or retraction process. This can reduce the amount of drag created by the landing gear, which in turn can help permit an increased maximum take-on weight (NITOW) of the aircraft and can help decrease an amount of noise generated by the aircraft. In some embodiments, edge detection aids, such as markings, are used to assist in edge detection and increase the accuracy of the results. Such edge detection aids may be provided on the at least one landing gear component.

[0047] The ability to produce a substantially real-time image of the landing bay allows functions and movements of the at least one landing gear component 4 to be monitored. For example, the extension and retraction time of the landing gear may be measured. This measurement may be used for diagnostic processes. Moreover, the at least one landing gear component 4 may be monitored so as to determine, for example, its condition and detect any failures.

[0048] In some embodiments, the landing gear position sensing system 1 may detect leaks or failures in the at least one landing gear component 4. For example, the at least one landing gear component 4 may comprise a hydraulic component and the landing gear position sensing system 1 may be configured to detect a leak of hydraulic fluid, such as by identifying hydraulic fluid on the surface of a component or following a determination that the extension or retraction time of the landing gear is greater than a predetermined normal" period. Alternatively or additionally, the landing gear position sensing system 1 may detect a damaged or missing component, such as a spring. In some embodiments, the landing gear position sensing system I may detect such leaks, failures or missing components through an image comparison between an expected/reference image (free of foreign objects) and a measured image (e.g. a real-time image). The expected/reference image may be a stored image that is accessible by the controller 5 [0049] In some embodiments, the landing gear position sensing system 1 may be configured to provide an indication to an operator when a failure and/or inconsistency is detected. For example, if the landing gear position sensing system 1 determines that the at least one landing gear component 4 has not deployed correctly before landing, the operator may be provided with an indication to abort the landing.

[0050] In some embodiments, the landing gear position sensing system 1 may be used in conjunction with one or more conventional measurement gauges. For example, the at least one landing gear component 4 may comprise a shock absorber. The shock absorber may be connected to a pressure gauge which is configured to determine and display an indication of a pressure within the shock absorber. In one embodiment, pressure gauge may be within the field of view of the at least one energy receiver 3 and/or the at least one energy transmitter 2 such that the landing gear position sensing system I can determine the indication on the pressure gauge.

[0051] As shown in Figure 2, in some embodiments the at least one energy transmitter 2 may be moveable relative to the at least one energy transmitter 3. As the at least one energy transmitter 2 is provided on a moveable landing gear component (in the example of Figure 2, on a strut of the landing gear), when the at least one landing gear component 4 moves, so too will the at least one energy transmitter 2. In the illustrated embodiment, the at least one energy transmitter 2 is moveable relative to the at least one energy receiver 3 and the landing gear bay. In some other embodiments, alternatively or additionally, the at least one energy receiver 3 may be moveable relative to the at least one energy transmitter 2 and the landing gear bay.

[0052] Although the at least one energy transmitter 2 is provided on the landing gear component 4 in Figure 2, in some embodiments, the at least one energy transmitter 2 and the at least one energy receiver 3 are posited remote from the at least one landing gear component 4. The at least one landing gear component 4 may be moveable relative to the at least one energy transmitter 2 and the at least one energy receiver 3. For example, the at least one energy transmitter 2 may be positioned opposite the at least one energy receiver 3 such that when an object (e.g. the at least one landing gear component 4) passes between the at least one energy transmitter 2 and the at least one energy receiver 3, it alters or breaks communication between the two. This arrangement may be used to indicate that at least one landing gear component 4 is in a certain position, for example a stowed position.

[0053] In some embodiments, an aircraft controller 5, such as the controller 5 of Figure 1 or the controller 5 of Figure 2, is configured to receive data from at least one energy receiver 3, wherein the energy is indicative of a first property and a second property of at least one landing gear component 4. The aircraft controller 5 may be configured to determine a first status and a second status of the at least one landing gear component 4 on the basis of the data. Advantageously, this allows a single energy receiver 3 to be used to determine multiple properties or statuses of the at least one landing gear component 4. Using a single energy receiver 3 to monitor the at least one landing gear component, where previously many sensors would have been used, saves space, leads to lower costs and makes replacement and maintenance easier. Moreover, by using fewer sensors than a conventional system, there are correspondingly fewer electrical connections to the sensors. As such, potential damage to such connections (for example due to impact from debris) and the resultant off-lining of the sensors can be reduced.

[0054] In some embodiments, the first and second properties may include at least one of position, temperature, structural rigidity and/or rotational velocity. In some embodiments, the first and second statuses may include at least one of: landing gear position, tyre condition and brake condition.

[0055] For example, the aircraft controller 5 may receive data from at least one energy receiver 3 that is indicative of the position and temperature of a landing gear tyre This data can then be used to determine the position of the tyre (and, by extension, the landing gear) while also estimating or determining a condition of the tyre. For example, the tyre may be provided with a thermo-reactive colour change strip which changes colour depending on the temperature of the tyre, or a radio frequency identification (RFID) tag equipped with a subsurface temperature transducer. The aircraft controller 5 may receive data indicative of the temperature of the tyre from the colour change strip or RFID tag, while also receiving data indicative of their position (and therefore the tyre's position).

[0056] In some embodiments, the at least one energy receiver 3 may comprise an RFID tag and the at least one energy transmitter may comprise an RFID reader. The RFID tag may be positioned on the at least one landing gear component 4 and contain information about that component (e.g. the year of manufacture, the number of uses, the date of last inspection, the serial number, and/or the manufacturer). When interrogated by the RFID reader, the AHD tag may transmit this information to the RFID reader which may be transmitted to the controller 5.

[0057] In some embodiments, the landing gear position sensing system 1 may be configured to determine if a foreign object is present in the system. For example, the landing gear position sensing system may be configured to determine whether debris has entered a landing gear bay. Such a determination may not be possible with conventional proximity sensors. In some embodiments, the landing gear position sensing system 1 may detect a foreign object through an image comparison between an expected/reference image (free of foreign objects) and a measured image (e.g. a real-time image). The expected/reference image may be a stored image that is accessible by the controller 5. This technique may similarly be used to determine the condition of components, for example landing gear tyres. In some embodiments, the landing gear position sensing system I may be configured to determine whether a person or other animal is within an operating area. If the landing gear position sensing system I detects a person or other animal, it may cause the automatic shutdown of certain systems or components to reduce, for example, the risk of injury to said person or other animal.

[0058] In some embodiments, the landing gear position sensing system 1 may utilise digital image processing. Such digital image processing may include: detection of the positions of components in a first image, such as through the use of suitable edge finding I 3 software that is configured to process the received image(s) and identify the positions of points and/or edges in the image(s); and comparison of the identified positions with comparative positions of the points and/or edges in a second image. The first image can, for example, be a recent or substantially real-time image of one or more components of the landing gear system. The second image can be a reference image of the system in good working order, for example, and may be stored in storage that is accessible to the controller 5. Images may be captured and analysed in this way over several respective flights, and the positions of the points and/or edges in the respective images compared to see if there is any progressive creep and/or inconsistencies of the points and/or edges over a plurality of flights, which could be indicative of degradation of one or more components in the landing gear system.

100591 In some embodiments, the landing gear position sensing system may further comprise a cleaning apparatus to clean the at least one energy transmitter 2 and/or the at least one energy receiver 3. For example, the cleaning apparatus may comprise a fluid jet which directs fluid towards the at least one energy transmitter 2 and/or the at least one energy receiver 3. Additionally or alternatively, the cleaning apparatus may comprise a translucent film which is provided over at least a part of the at least one energy transmitter 2 and/or the at least one energy receiver 3. The translucent film may be provided as a length of roll such that a portion of the film can be moved away from the at least one energy transmitter 2 and/or the at least one energy receiver 3 when it becomes dirty and replaced with a clean portion of the film. The at least one energy transmitter 2 and/or the at least one energy receiver 3 may have a self-cleaning lens cover, such as a cover that operates according to an electrowetting principle as described at the following URL: http://microsystems.mju.ac.kr/8277. Advantageously, such cleaning may prevent incorrect or inaccurate readings that may occur if either or both of the at least one energy transmitter 2 and the at least one energy receiver 3 are dirty.

[00601 Figure 3 shows a method 30 of operating a controller to determine a status of at least one landing gear component 4. The method comprises receiving 31 data from at least one energy receiver 3 indicative of the status of that at least one landing gear component 4, and determining 32 the status of the at least one landing gear component 4 on the basis of the data. The method 30 may be performed by the controller 5 of either Figure 1 or the controller 5 of Figure 2, for example The landing gear component(s) 4 may be any one or more of those discussed herein [0061] In one embodiment, the method 30 may further include providing 33 an indication of the status of the at least one landing gear component 4 to an operator. For example, the status may be that the landing gear is extended or retracted. The indication may be given to the flight crew in the cockpit. The indication could be visual, audible or tactile, for example, such as by way of illuminating a light, sounding a beeper or buzzer, or operating a vibration device.

[0062] Figure 4 shows a schematic diagram of a non-transitory computer-readable storage medium 40 according to one embodiment. The non-transitory computer-readable storage medium 40 stores instructions 43 that, if executed by a processor 42 of an aircraft controller 41, cause the processor 42 to perform one of the methods described herein. In some examples, the aircraft controller 41 is the aircraft controller 5 described above with reference to Figures I and 2 or a variant thereof described herein. The instructions 43 may comprise instructions to perform any of the methods 30 described above with reference to Figure 3.

[0063] Figure 5 shows an aircraft 100 comprising a landing gear system as described herein. The aircraft 100 may comprise at least one landing gear component 4, along with a landing gear position sensing system 1. The landing gear position sensing system may be any landing gear position sensing system described herein. The aircraft 100 may further comprise a non-transitory computer-readable medium as described above with reference to Figure 4.

[0064] It is to noted that the term or as used herein is to be interpreted to mean -and/or", unless expressly stated otherwise [0065] The above embodiments are to be understood as illustrative examples of the invention. Further embodiments of the invention are envisaged. It is to be understood that any feature described in relation to any one embodiment may be used alone, or in combination with other features described, and may also be used in combination with one or more features of any other of the embodiments, or any combination of any other of the embodiments. Furthermore, equivalents and modifications not described above may also be employed without departing from the scope of the invention, which is defined in the accompanying claims.

Claims

CLAIMS: 1. A landing gear position sensing system comprising: a position measuring system configured to measure a position of at least one landing gear component, the position measuring system comprising: at least one energy transmitter and at least one energy receiver; wherein the at least one energy receiver is configured to receive energy from the at least one energy transmitter in use, a characteristic of the energy being indicative of the position of the at least one landing gear component.
2 The landing gear position sensing system according to claim 1, further comprising a controller configured to: receive information representative of the energy received by the at least one energy receiver; and determine the position of the at least one landing gear component based on the information.
3. The landing gear position sensing system according to claim 1 or claim 2, wherein the at least one energy transmitter and the at least one energy receiver are comprised in a unitary item.
4. The landing gear position sensing system according to claim 1 or claim 2, wherein the at least one energy transmitter and the at least one energy receiver are mountable in separate discrete positions.
The landing gear position sensing system according to any preceding claim, wherein the energy is electromagnetic energy.
6. The landing gear position sensing system according to any preceding claim, wherein the at least one energy receiver is a lidar sensor and the at least one energy transmitter is a lidar transmitter.
7. The landing gear position sensing system according to any preceding claim, wherein the at least one energy transmitter is a laser.
8. A landing gear system comprising: at least one landing gear component; and a landing gear position sensing system, wherein the landing gear position sensing system comprises: a position measuring system configured to measure a position of at least one landing gear component, the position measuring system comprising: at least one energy transmitter and at least one energy receiver; wherein the at least one energy receiver is configured to receive energy from the at least one energy transmitter in use, a characteristic of the energy being indicative of the position of the at least one landing gear component.
9. The landing gear system according to claim 8, wherein at least one of the at least one energy transmitter and the at least one energy receiver is provided on the at least one landing gear component.
10. The landing gear system according to any one of claims 8 to 9, wherein the at least one energy transmitter is movable relative to the at least one energy receiver.
11. The landing gear system according to any one of claims 8 to 10, wherein the at least one energy transmitter and the at least one energy receiver are positioned remote from the at least one landing gear component, and the at least one landing gear component is movable relative to the at least one energy transmitter and the at least one energy receiver.
12. The landing gear system according to any one of claims 8 to 11, wherein the at least one landing gear component is at least one of: a landing gear, part of a landing gear movement mechanism for moving the landing gear, a landing gear bay door, part of a landing gear bay door movement mechanism for moving the landing gear bay door, and an uplock for retaining a landing gear or a landing gear bay door in position.
13. An aircraft controller configured to: receive data from at least one energy receiver, the data being indicative of a first and a second property of at least one landing gear component; and determine a first and a second status of the at least one landing gear component on the basis of the data.
14. The aircraft controller according to claim 13, wherein the first and the second property include at least one of position, temperature, structural rigidity and rotational velocity.
15. The aircraft controller according to any one of claims 13 to 14, wherein the first and the second status include at least one of landing gear position, tyre condition and brake condition.
16. A method of operating a controller to determine a status of at least one landing gear component, the method comprising: receiving data from at least one energy receiver indicative of the status of the at least one landing gear component; and determining the status of the at least one landing gear component on the basis of the data.
17 The method according to claim 16, further comprising providing an indication of the status of the at least one landing gear component to an operator.
18. A non-transitory computer-readable storage medium storing instructions that, if executed by an aircraft controller, cause the aircraft controller to carry out the method according to claim 16 or claim 17
19. An aircraft comprising the landing gear position sensor system according to any one of claims 1 to 7, the landing gear system according to any one of claims 8 to 12, the aircraft controller according to any one of claims 13 to 15, or the non-transitory computer-readable storage medium according to claim 18