Electromagnetic assisted system for an aircraft, aircraft and control method

Abstract

The application relates to an electromagnetic auxiliary system for an aircraft, the aircraft and a control method. The electromagnetic auxiliary system comprises a metal component arranged below a runway, an electromagnetic actuator arranged on an aircraft body of the aircraft, the electromagnetic actuator comprising a plurality of excitation coils arranged in sequence in a direction from a front end to a rear end of the aircraft body, the plurality of excitation coils being configured to be powered to selectively generate a vertical magnetic attraction force in a downward direction together with the metal component or simultaneously generate the vertical magnetic attraction force in the downward direction and a reverse magnetic force in a direction opposite to a moving direction of the aircraft, and a lifting component connected to the electromagnetic actuator and used for connecting the aircraft body, the lifting component being configured to drive the electromagnetic actuator to lift in a vertical direction. The reverse magnetic force can assist the aircraft in braking, the vertical magnetic attraction force can increase the friction between the aircraft and the ground, improve the braking capacity of the aircraft, solve the problem that the aircraft wheels are prone to skidding, and facilitate stable parking of the aircraft.

Description

Technical Field

[0001] This application relates to the field of aircraft technology, and in particular to electromagnetic auxiliary systems for aircraft, aircraft and control methods thereof. Background Technology

[0002] With the rapid development of modern air transport, the operational efficiency and safety of aircraft, as the most important means of transportation, have always been core concerns in the aviation field.

[0003] Aircraft operations on the ground at airports mainly involve braking after landing and taxiing. Braking is mostly achieved using hydraulic or electric wheel brakes, while taxiing and turning often involve controlling the nose wheel deflection and differential braking. These operations rely on the friction between the wheels and the runway. However, as an open environment, airport runways are easily contaminated, which reduces the friction between the wheels and the runway. This can easily lead to wheel spin / tacking, resulting in loss of braking force, decreased turning performance, and in severe cases, even runway overruns. Summary of the Invention

[0004] Therefore, it is necessary to provide an electromagnetic auxiliary system, an aircraft, and a control method for aircraft that are prone to slippage due to reduced friction between the wheels and the runway caused by runway contamination during braking and taxiing.

[0005] An electromagnetic assistance system for an aircraft, the electromagnetic assistance system comprising:

[0006] Metal components are disposed below the airstrip, which is configured to allow the aircraft to take off, land, taxi, and park.

[0007] An electromagnetic actuator is disposed on the aircraft body of the aircraft. The electromagnetic actuator includes a plurality of excitation coils arranged sequentially along the front end to the rear end of the aircraft body. The plurality of excitation coils are configured to be energized to selectively generate a downward vertical magnetic attraction force together with the metal component, or to simultaneously generate a downward vertical magnetic attraction force and a reverse magnetic force opposite to the direction of movement of the aircraft.

[0008] A lifting assembly is connected to the electromagnetic actuator and is used to connect to the aircraft body. The lifting assembly is configured to drive the electromagnetic actuator to lift vertically.

[0009] In one embodiment, the metal component includes a metal mesh and / or a metal plate.

[0010] In one embodiment, the airfield includes a take-off and landing runway for the aircraft to take off and land;

[0011] The metal component includes a first metal part and a second metal part. The first metal part is closer to the landing runway than the second metal part, and the effective conductive area of ​​the first metal part is smaller than the effective conductive area of ​​the second metal part.

[0012] The first metal component is a metal mesh or a metal plate, and the second metal component is a metal mesh or a metal plate.

[0013] An aircraft includes an aircraft body and an electromagnetic actuator and a lifting assembly of the electromagnetic auxiliary system in any of the above embodiments, wherein the lifting assembly is disposed on the landing gear of the aircraft body.

[0014] A control method for an electromagnetic auxiliary system for an aircraft as described in any of the above embodiments, the control method comprising:

[0015] Confirm that the aircraft's moving speed is greater than 0 m / s;

[0016] If a braking signal is received, then control any two adjacent excitation coils among the multiple excitation coils to be energized with direct current in opposite directions, generating a downward vertical magnetic attraction force and a reverse magnetic force opposite to the direction of movement of the aircraft.

[0017] If not, then each of the plurality of excitation coils is supplied with direct current in the same direction, or alternating current is supplied to each of the plurality of excitation coils, such that the magnetic field moves at the same speed as the aircraft, so as to generate a downward vertical magnetic attraction force.

[0018] In one embodiment, when the aircraft's moving speed is greater than 0 m / s, the control method further includes:

[0019] If a braking signal is received, the lifting assembly is controlled to drive the electromagnetic actuator to descend to a first preset height; if no braking signal is received, the lifting assembly is controlled to drive the electromagnetic actuator to descend to a second preset height.

[0020] When the aircraft is located in the airfield, the maximum height of the electromagnetic actuator relative to the airfield is Hmm, and both the first preset height and the second preset height are less than Hmm.

[0021] In one embodiment, the control method further includes:

[0022] Confirm that the aircraft's moving speed is equal to 0 m / s;

[0023] The excitation coils are energized to generate a downward-directed vertical magnetic attraction.

[0024] In one embodiment, when the aircraft's moving speed is 0 m / s, the control method further includes:

[0025] The lifting assembly is controlled to drive the electromagnetic actuator to descend to a third preset height, or to descend until it touches the field channel.

[0026] When the aircraft is located in the airfield, the maximum height of the electromagnetic actuator relative to the airfield is Hmm, and the third preset height is less than Hmm.

[0027] A control method for an aircraft as described in any of the above embodiments, the aircraft having a braking system configured to provide braking torque, wherein when the aircraft's moving speed is greater than 0 m / s, the control method includes:

[0028] Upon confirming receipt of the braking signal, the current I1 (A) of the excitation coil is obtained, and a braking torque Tm (N·m) is provided, where Tm ≤ μ(F1+Fz1)R, where μ is the coefficient of friction between the aircraft's wheels and the runway; F1 is the aircraft's own weight; Fz1 is the vertical magnetic attraction force when the current of the excitation coil is I1, N, Fz1≥0, 0≤I1≤Imax; and R is the radius of the aircraft's wheels, m.

[0029] Determine whether the current current I1 of the excitation coil is equal to Imax. If yes, maintain the current of the excitation coil at Imax. If no, control the current of the excitation coil to increase at a set rate and control the braking torque to increase at a preset rate. The maximum value of the braking torque increasing from Tm is μ(Fzmax-Fz1)R.

[0030] Where Fzmax is the vertical magnetic attraction force (N) when the current of the excitation coil is Imax.

[0031] In one embodiment, when the aircraft's moving speed is greater than 0 m / s, the control method further includes:

[0032] Confirmation received of slippage signal;

[0033] Determine whether a braking signal is received. If a braking signal is received, obtain the current control torque Tm (N·m) and determine whether the current current I1 of the excitation coil is equal to Imax, where 0≤I1≤Imax; if yes, control the braking torque to decrease from Tm to Tn1, where μ(F1+Fzmax)R≥Tn1≥μF1R; if no, control the braking torque to decrease from Tm to Tn2 in sequence, control the current of the excitation coil to increase from I1 at a set rate, and control the braking torque to increase at a preset rate, and the maximum value of the braking torque increase from Tm is μ(Fzmax-Fz1)R, where μ(F1+Fz1)R≥Tn2≥μF1R;

[0034] If no braking signal is received, and it is confirmed that the current I1 of the excitation coil is less than Imax, the current of the excitation coil is controlled to increase at a set rate.

[0035] Wherein, Imax is the maximum current of the excitation coil, A; μ is the coefficient of friction between the aircraft's wheels and the runway; F1 is the aircraft's own weight, N; Fzmax is the vertical magnetic attraction force when the maximum current of the excitation coil is Imax, N; Fz1 is the vertical magnetic attraction force when the excitation coil's current is I1, N; and R is the radius of the aircraft's wheels, m.

[0036] The aforementioned electromagnetic auxiliary system for aircraft comprises electromagnetic actuators, a lifting assembly, and a metal assembly. The metal assembly is located beneath the airstrip, which serves as the landing, taxiing, and parking area for the aircraft. The electromagnetic actuator includes multiple excitation coils arranged sequentially from the front to the rear of the aircraft. When the aircraft lands on the airstrip, it generates a downward vertical magnetic attraction and a reverse magnetic force. The vertical magnetic attraction increases the friction between the aircraft and the ground, mitigating slippage. Furthermore, the presence of the vertical magnetic attraction increases the aircraft's maximum braking torque. Combined with the reverse magnetic force's resistance to aircraft movement, this decelerates the aircraft and reduces braking distance. Similarly, when the aircraft taxis on the airstrip, it generates a downward vertical magnetic attraction, further increasing friction and mitigating slippage. The lifting assembly drives the electromagnetic actuators to rise and fall, adjusting the magnetic field strength.

[0037] Furthermore, when the aircraft is parked on the runway, a downward vertical magnetic force is generated, which helps the aircraft to park stably. At this time, the lifting assembly can drive the electromagnetic actuator to descend to a lower altitude or make the electromagnetic actuator contact the runway, increasing the vertical magnetic force and improving the parking stability of the aircraft. Attached Figure Description

[0038] Figure 1 This is a schematic diagram of the structure of an electromagnetic auxiliary system for an aircraft provided in some embodiments of this application.

[0039] Figure 2 for Figure 1 A schematic diagram of the metal components of the electromagnetic auxiliary system.

[0040] Figure 3 for Figure 1 A schematic diagram of the electromagnetic actuator and lifting assembly of the electromagnetic auxiliary system.

[0041] Figure 4 for Figure 1 A schematic diagram of the electromagnetic actuator and lifting assembly of the electromagnetic auxiliary system from another perspective.

[0042] Figure 5 for Figure 1 Schematic diagram of the working principle of the electromagnetic auxiliary system in the middle Figure 1 .

[0043] Figure 6 for Figure 1 Schematic diagram of the working principle of the electromagnetic auxiliary system in the middle Figure 2 .

[0044] Figure 7 A flowchart illustrating a control method for an electromagnetic auxiliary system for an aircraft, provided for some embodiments of this application.

[0045] Figure 8 for Figure 1 Schematic diagram of the working principle of the electromagnetic auxiliary system in the middle Figure 3 .

[0046] Figure 9 A flowchart illustrating a control method for an electromagnetic auxiliary system for an aircraft, provided for some embodiments of this application.

[0047] Figure 10 A flowchart illustrating a control method for an aircraft provided in some embodiments of this application.

[0048] Figure 11 A flowchart illustrating a control method for an aircraft provided in some embodiments of this application.

[0049] in:

[0050] 1. Aircraft; 11. Aircraft body; 111. Landing gear; 1111. Wheels; 12. Electromagnetic actuator; 121. Excitation coil; 13. Lifting assembly.

[0051] 2. Metal components; 21. Metal mesh; 22. Metal plate.

[0052] 3. Venue. Detailed Implementation

[0053] To make the above-mentioned objectives, features, and advantages of this application more apparent and understandable, the specific embodiments of this application are described in detail below with reference to the accompanying drawings. Many specific details are set forth in the following description to provide a thorough understanding of this application. However, this application can be implemented in many other ways different from those described herein, and those skilled in the art can make similar modifications without departing from the spirit of this application. Therefore, this application is not limited to the specific embodiments disclosed below.

[0054] In the description of this application, it should be understood that if terms such as "center", "longitudinal", "lateral", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", "axial", "radial", "circumferential" appear, these terms indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, and are only for the convenience of describing this application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this application.

[0055] Furthermore, where the terms "first" and "second" appear, these terms are for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined with "first" or "second" may explicitly or implicitly include at least one of that feature. In the description of this application, where the term "multiple" appears, "multiple" means at least two, such as two, three, etc., unless otherwise explicitly specified.

[0056] In this application, unless otherwise expressly specified and limited, the terms "installation," "connection," "joining," and "fixing," etc., should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components, unless otherwise expressly limited. Those skilled in the art can understand the specific meaning of the above terms in this application based on the specific circumstances.

[0057] In this application, unless otherwise expressly specified and limited, the use of descriptions such as "above" or "below" the second feature indicates that the first and second features are in direct contact or indirect contact via an intermediate medium. Furthermore, "above," "on top of," and "over" the second feature can mean that the first feature is directly above or diagonally above the second feature, or simply that the first feature is at a higher horizontal level than the second feature. Similarly, "below," "below," and "under" the second feature can mean that the first feature is directly below or diagonally below the second feature, or simply that the first feature is at a lower horizontal level than the second feature.

[0058] It should be noted that if an element is referred to as being "fixed to" or "set on" another element, it can be directly on the other element or there may be an intervening element. If an element is considered to be "connected to" another element, it can be directly connected to the other element or there may be an intervening element. If so, the terms "vertical," "horizontal," "upper," "lower," "left," "right," and similar expressions used in this application are for illustrative purposes only and do not represent the only possible implementation.

[0059] See Figures 1 to 4 , Figure 1 A schematic diagram of the structure of an electromagnetic auxiliary system for an aircraft according to an embodiment of this application is shown. Figure 2 It shows Figure 1 A schematic diagram of the metal components of the electromagnetic auxiliary system. Figure 3 It shows Figure 1 A schematic diagram of the electromagnetic actuator and lifting assembly of the electromagnetic auxiliary system. Figure 4 The diagram shows a structural schematic of the electromagnetic actuator and lifting assembly of the electromagnetic auxiliary system from another perspective.

[0060] Some embodiments of this application provide an electromagnetic auxiliary system for an aircraft, including a metal component 2 disposed below an airstrip 3 configured to allow the aircraft 1 to take off, land, taxi, and park.

[0061] The aforementioned airfield 3 includes a runway, taxiway, and apron. Taking aircraft 1 as an example, the runway is for takeoff and landing, the apron is the parking area for aircraft, and the taxiway is the road connecting the runway and the apron, allowing aircraft to taxi and shuttle, but without takeoff or landing function. In other words, aircraft 1 uses a conventional horizontal takeoff and landing mode for takeoff and landing, and aircraft 1 has landing gear, like a commercial airliner.

[0062] See Figure 1 and Figure 2The aforementioned metal component 2 includes a metal mesh 21 and / or a metal plate 22. The metal mesh 21 and / or metal plate 22 positioned below the channel 3 not only generate magnetic force in conjunction with the electromagnetic actuator 12, but also enhance the strength of the channel 3.

[0063] In one specific implementation, the airfield 3 includes a takeoff and landing runway for aircraft takeoff and landing. The metal assembly 2 includes a first metal component and a second metal component, both disposed below the takeoff and landing runway. The first metal component is closer to the starting point of the takeoff and landing runway than the second metal component when the aircraft 1 lands. The effective conductive area of ​​the first metal component is smaller than that of the second metal component. The first metal component is a metal mesh 21 or a metal plate 22. The second metal component is a metal mesh 21 or a metal plate 22.

[0064] Understandably, as aircraft 1 lands on the runway, it gets closer and closer to the runway until it touches it. This allows the first metal component to be placed at the landing point, and then the second metal component to be placed behind the first metal component, which can reduce costs.

[0065] For example, see Figure 2 The first metal component is selected as metal mesh 21, and the second metal component is selected as metal plate 22.

[0066] Among them, aircraft 1 can be an aircraft that uses conventional take-off and landing methods, that is, taxiing take-off and landing, such as a civil aircraft.

[0067] Of course, another specific implementation method is to place metal components on the rear side of the runway during landing, but not on the front side. Alternatively, two types of metal meshes or plates with different effective conductive areas can be arranged, with the metal mesh or plate with the smaller effective conductive area closer to the starting point of the runway during landing.

[0068] See Figure 1 , Figure 3 and Figure 4 The electromagnetic auxiliary system also includes an electromagnetic actuator 12. The electromagnetic actuator 12 is disposed on the aircraft body 11 of the aircraft 1, and includes multiple excitation coils 121 arranged sequentially along the front end to the rear end of the aircraft body 11. The multiple excitation coils 121 are configured to be energized to selectively generate a downward vertical magnetic attraction force together with the metal component 2, or simultaneously generate a downward vertical magnetic attraction force and a reverse magnetic force opposite to the direction of movement of the aircraft 1.

[0069] Understandably, when the excitation coil 121 is energized, it generates an electromagnetic field. When the aircraft 1 moves on the track 3, the metal component 2 cuts the magnetic field lines of the electromagnetic field, generating an induced current. This current can convert the kinetic energy of the aircraft 1 into heat energy and dissipate it. The induced magnetic field interacts with the magnetic field generated by the electromagnetic actuator, producing a vertical magnetic attraction force and a reverse magnetic force. The vertical magnetic attraction force can increase the friction between the aircraft 1 and the track 3, while the reverse magnetic force can hinder the movement of the aircraft 1 and decelerate it.

[0070] See Figure 3 and Figure 4 The electromagnetic actuator 12 also includes a magnetic yoke and pole shoes. The magnetic yoke and pole shoes are made of a high-permeability material.

[0071] See Figure 3 and Figure 4 The electromagnetic auxiliary system also includes a lifting assembly 13, which is connected to the electromagnetic actuator 12. The lifting assembly 13 is used to connect to the aircraft body 11 and to drive the electromagnetic actuator 12 to move up and down in the vertical direction.

[0072] Understandably, the distance between the electromagnetic actuator 12 and the runway 3 can be adjusted via the lifting assembly 13. This allows for the adjustment of the electromagnetic force, such as when the aircraft 1 is parked on the runway 3, the electromagnetic actuator 12 can be brought into contact with the runway 3, increasing the vertical magnetic attraction and facilitating stable parking of the aircraft 1. When the aircraft 1 moves, a set distance can be maintained between the electromagnetic actuator 12 and the runway 3. This set distance can be fixed or adjusted in real-time based on the distance between the aircraft 1 and the runway 3. For example, when the aircraft 1 is landing, the distance between the electromagnetic actuator 12 and the runway 3 gradually decreases, but without contact with the runway 3, to avoid collision.

[0073] The lifting assembly 13 also employs a motor and lead screw structure to enable the electromagnetic actuator 12 to move vertically. Alternatively, a hydraulic actuator can be used, utilizing the flow of hydraulic oil to drive the piston rod in reciprocating linear motion, thereby raising or lowering the electromagnetic actuator 12. Of course, the lifting assembly 13 can also adopt other structures, which are not specifically limited here.

[0074] The electromagnetic auxiliary system provided in this embodiment includes an electromagnetic actuator 12, a lifting assembly 13, and a metal assembly 2. The metal assembly 2 is located below a runway 3, which is used for takeoff, landing, taxiing, and parking of the aircraft 1. The electromagnetic actuator 12 includes multiple excitation coils 121 arranged sequentially from the front end to the rear end of the aircraft 1. When the aircraft 1 lands on the runway 3, it generates a downward vertical magnetic attraction force and a reverse magnetic force. The vertical magnetic attraction force increases the friction between the aircraft 1 and the ground, improving the slippage problem. The presence of the vertical magnetic attraction force also increases the maximum braking torque of the aircraft 1. Combined with the reverse magnetic force's resistance to the aircraft 1's movement, this decelerates the aircraft 1 and reduces the braking distance. When the aircraft 1 taxis on the runway 3 (without braking), it generates a downward vertical magnetic attraction force, increasing the friction between the aircraft 1 and the ground and improving the slippage problem. The lifting assembly 13 drives the electromagnetic actuator 12 to rise and fall to adjust the magnetic field strength, thereby adjusting the electromagnetic force.

[0075] Furthermore, when the aircraft 1 is parked on the runway 3, a downward vertical magnetic force is generated, which is beneficial for the stable parking of the aircraft 1. At this time, the lifting assembly 13 can drive the electromagnetic actuator 12 to descend so that the electromagnetic actuator 12 contacts the runway 3, increasing the vertical magnetic force and improving the stability of the aircraft 1 when parked.

[0076] This embodiment also provides an aircraft 1, which includes an aircraft body 11 and an electromagnetic actuator 12 and a lifting assembly 13 of the electromagnetic auxiliary system described in the above embodiment. The lifting assembly 13 is disposed on the landing gear 111 of the aircraft body 11. The landing gear 111 is provided with wheels 1111.

[0077] Thus, the electromagnetic actuator 12 is housed in the landing gear bay along with the landing gear 111 during flight of the aircraft 1 for protection. When the aircraft 1 is preparing to land, it can be moved outside the landing gear bay along with the landing gear 111 to perform its function.

[0078] For example, the aircraft 1 is selected as a civil aircraft, which takes off and lands using conventional methods, that is, on a runway. Of course, the aircraft 1 can also be other types of aircraft, such as drones, which can take off by taxiing on an airstrip and land by taxiing.

[0079] Figure 5 It shows Figure 1 Schematic diagram of the working principle of the electromagnetic auxiliary system in the middle Figure 1 . Figure 6 It shows Figure 1 Schematic diagram of the working principle of the electromagnetic auxiliary system in the middle Figure 2 . Figure 7 Flowcharts of control methods for electromagnetic auxiliary systems of aircraft in some embodiments are shown.

[0080] This embodiment also provides a control method for an electromagnetic auxiliary system for an aircraft.

[0081] See Figures 5 to 7 In some embodiments, the control method includes:

[0082] Confirm that the moving speed of aircraft 1 is greater than 0 m / s.

[0083] If a braking signal is received, then control any two adjacent excitation coils 121 to be energized with direct current in opposite directions, generating a downward vertical magnetic attraction force Fz and a reverse magnetic force Fx opposite to the direction of movement of the aircraft 1.

[0084] If not, then each of the multiple excitation coils 121 is supplied with direct current in the same direction, or each of the multiple excitation coils 121 is supplied with alternating current, such that the magnetic field moves at the same speed as the aircraft 1, to generate a downward vertical magnetic attraction force Fz. The main force generated is the downward vertical magnetic attraction force Fz, along with a small or negligible reverse magnetic force Fx opposite to the direction of the aircraft's movement.

[0085] For details, please refer to Figure 5 During the braking process of aircraft 1, such as the landing phase, any two adjacent excitation coils 121 can be energized with direct current in opposite directions. This generates a downward vertical magnetic attraction force Fz and a reverse magnetic force Fx opposite to the direction of aircraft 1's movement. This increases friction (the presence of the vertical magnetic attraction force Fz increases the normal force, which is the sum of the aircraft 1's weight and the vertical magnetic attraction force Fz, thus increasing friction), improving the slippage problem. Furthermore, the reverse magnetic force Fx can be used to decelerate aircraft 1. The direction of aircraft 1's movement is as follows: Figure 5 The OX direction is indicated by the middle arrow.

[0086] In this situation, when the speed of aircraft 1 moving on airfield 3 is greater than 0 m / s, it is determined whether a braking signal has been received. (See also...) Figure 5If a braking signal is received at this time, the system controls any two adjacent excitation coils 121 to be energized with direct current in opposite directions. This generates an induced magnetic field with alternating N and S poles. Magnetic lines of force originate from the N pole, pass through the air gap, pass through the metal components installed in the air passage, return to the S pole through the air gap, and then return to the N pole, thus forming a closed magnetic circuit. As the electromagnetic actuator 12 moves with the aircraft 1, the magnetic flux through a certain area of ​​the metal component 2 changes. According to Faraday's law of electromagnetic induction, the metal component 2 will generate an induced current, also known as an eddy current. At the same time, the eddy current generates a counter-magnetic field, which interacts with the magnetic field of the electromagnetic actuator 12, generating a vertical magnetic attraction force Fz and a reverse magnetic force Fx, which hinder the movement of the electromagnetic actuator 12, i.e., the aircraft 1. Furthermore, from an energy perspective, the kinetic energy of the electromagnetic actuator 12 is dissipated as heat by the induced current flowing through the metal component 2. At this time, braking of the aircraft 1 can be achieved without relying on the friction between the wheels and the air passage.

[0087] At this point, under ideal conditions, the theoretical formulas for the vertical magnetic attraction force Fz (N) and the reverse magnetic force Fx (N) generated by a single excitation coil 121 of the electromagnetic actuator 12 are as follows:

[0088]

[0089]

[0090] Where Bb is the magnetic flux density, T; v represents the velocity of the electromagnetic actuator 12 relative to the field channel 3, which is assumed to be the velocity of the aircraft 1, m / s; τ is the distance between adjacent magnetic poles, m; ρ represents the resistivity of the metal component 2, Ω⋅m; δ represents the skin depth, m; D represents the diameter of the eddy current generation region, m; and S represents the effective magnetic flux area, m. 2 μ0 is the vacuum permeability, H / m.

[0091] See Figure 6When aircraft 1 is taxiing (without braking), such as during its movement from the runway to the apron via the taxiway, or vice versa, in one scenario, each of the multiple excitation coils 121 can be energized with a direct current in the same direction to generate a downward vertical magnetic attraction force Fz and a reverse magnetic force Fx opposite to the direction of aircraft 1's movement. In this case, the reverse magnetic force Fx is small and its deceleration effect on aircraft 1 is negligible. In another scenario, each of the multiple excitation coils 121 can be energized with an alternating current, making the magnetic field's moving speed the same as the aircraft 1's moving speed, to generate a downward vertical magnetic attraction force Fz. In this case, the magnetic field's moving speed is vm, where vm = 2fτ, f is the excitation frequency, and τ is the distance between adjacent magnetic poles. Theoretically, no eddy currents are generated, and the reverse magnetic force Fx is zero. The direction of aircraft 1's movement is as follows: Figure 6 The arrow points in the OX direction. In both cases, the vertical magnetic attraction Fz increases the friction between aircraft 1 and the track 3, thus allowing for greater friction without slippage under a limited coefficient of friction.

[0092] In an ideal scenario, taking the control of multiple excitation coils 121 to pass alternating current through each excitation coil 121, and making the magnetic field moving at the same speed as the aircraft 1, as an example, the theoretical formulas for the vertical magnetic attraction force Fz and the reverse magnetic force Fx generated by a single excitation coil 121 of the electromagnetic actuator 12 are as follows:

[0093]

[0094]

[0095] The principle of the magnetic field during the gliding process of aircraft 1 is similar to the principle of the magnetic field generation during the braking process, and will not be elaborated here.

[0096] Furthermore, when the moving speed of aircraft 1 is greater than 0 m / s, the control method of the electromagnetic auxiliary system also includes:

[0097] If a braking signal is received, the control lifting assembly 13 drives the electromagnetic actuator 12 to descend to a first preset height. If no braking signal is received, the control lifting assembly 13 drives the electromagnetic actuator 12 to descend to a second preset height. When the aircraft 1 is located on the airfield 3, the maximum height of the electromagnetic actuator 12 relative to the airfield 3 is H mm, and both the first and second preset heights are less than H mm.

[0098] In other words, when aircraft 1 brakes, the electromagnetic force can be increased by reducing the distance between electromagnetic actuator 12 and the runway 3. However, the height at which electromagnetic actuator 12 descends must be less than H mm to avoid collision between electromagnetic actuator 12 and runway 3 when aircraft 1 moves. Similarly, when aircraft 1 is gliding, the electromagnetic force can also be increased by reducing the distance between electromagnetic actuator 12 and runway 3. However, the height at which electromagnetic actuator 12 descends must be less than H mm to avoid collision between electromagnetic actuator 12 and runway 3 when aircraft 1 moves.

[0099] It should be noted that the first preset height and the second preset height can be set to be the same or different, and can be set according to actual needs. Furthermore, the process of the lifting component 13 driving the electromagnetic actuator 12 to descend can be set to descend to the desired position within a preset time, or it can be set to descend gradually as the current of the excitation coil 121 increases. Thus, the descent process of the lifting component 13 driving the electromagnetic actuator 12 is not specifically limited here.

[0100] Specifically, the magnetic field strength is directly proportional to the current and inversely proportional to the distance from the ground. That is, the magnetic field strength can be increased by increasing the current and / or decreasing the distance between the electromagnetic actuator 12 and the field channel 3, thereby increasing the vertical magnetic attraction force Fz and the reverse magnetic force Fx. The distance between the electromagnetic actuator 12 and the field channel 3 is achieved by driving the lifting assembly 13.

[0101] Figure 8 It showed Figure 1 Working principle of electromagnetic auxiliary system Figure 3 . Figure 9 Flowcharts of control methods for electromagnetic auxiliary systems used in aircraft are shown in some examples.

[0102] See Figure 8 and Figure 9 The above control methods also include:

[0103] Confirm that the moving speed of aircraft 1 is 0 m / s.

[0104] Multiple excitation coils 121 are energized to generate a downward vertical magnetic attraction force Fz.

[0105] Understandably, in this situation, the speed of aircraft 1 is 0 m / s, and aircraft 1 is in a stationary state. Since the speed of aircraft 1 is 0 m / s, only vertical magnetic attraction force Fz is generated at this time, which helps aircraft 1 to remain stationary.

[0106] Furthermore, when the moving speed of the aircraft 1 is equal to 0 m / s, the control method also includes: controlling the lifting assembly 13 to drive the electromagnetic actuator 12 to descend to a third preset height, or to descend to the point of contact with the airfield 3. Wherein, when the aircraft 1 is located in the airfield 3, the maximum height of the electromagnetic actuator 12 relative to the airfield 3 is H mm, and the third preset height is less than H mm.

[0107] When the electromagnetic actuator 12 contacts the field channel 3, the distance between the electromagnetic actuator 12 and the field channel 3 reaches its minimum value, which increases the vertical magnetic attraction force Fz, thereby further improving the stability of the aircraft 1 in the parking state. In this case, it is not necessary to install additional tethering cables on the aircraft 1, or to use tethering cables in conjunction with them to secure the aircraft 1, thus improving the parking stability of the aircraft 1.

[0108] It should be noted that when the aircraft 1 is in a parked state, the electromagnetic actuator 12 can also be kept out of contact with the airfield 3. In this case, the descent height of the electromagnetic actuator 12 can be set according to actual needs, and no specific limitation is made here.

[0109] This application embodiment also provides a control method for an aircraft. The aircraft 1 includes a braking system configured to provide braking torque. In this case, the aircraft 1 also includes an aircraft body 11, an electromagnetic actuator 12, and a lifting assembly 13. The lifting assembly 13 is connected to the landing gear 111 of the aircraft body 11 and is used to drive the electromagnetic actuator 12 to move up and down in the vertical direction.

[0110] Figure 10 A flowchart of a control method for an aircraft according to some embodiments of this application is shown.

[0111] See Figure 10 In some embodiments, when the moving speed of the aircraft 1 is greater than 0 m / s, the control method of the aircraft 1 includes:

[0112] Upon confirming receipt of the braking signal, the current I1 (A) of the excitation coil 121 is acquired, and the braking torque Tm (N·m) is provided, where Tm ≤ μ(F1+Fz1)R. Here, μ is the coefficient of friction between the aircraft's wheels 1111 and the runway 3; F1 is the weight of the aircraft 1 (N); Fz1 is the vertical magnetic attraction force when the current in the excitation coil 121 is I1 (Fz1 ≥ 0, 0 ≤ I1 ≤ Imax); and R is the radius of the aircraft's wheels 1111 (m).

[0113] Determine if the current of the excitation coil 121 is equal to Imax. If yes, maintain the current of the excitation coil 121 at Imax. If not, sequentially control the current of the excitation coil 121 to increase at a set rate and control the braking torque to increase at a preset rate, with the maximum increase in braking torque from Tm being μ(Fzmax-Fz1)R. Here, Fzmax is the vertical magnetic attraction force when the current of the excitation coil 121 is Imax.

[0114] Understandably, upon receiving a braking signal, the current I1 of the excitation coil 121 is acquired, and a braking torque Tm is provided, where Tm ≤ μ(F1+Fz1)R. Due to the presence of the vertical magnetic attraction Fz1, the maximum torque can reach μ(F1+Fz1)R, which is beneficial for the braking of aircraft 1. In this case, it is determined whether the current I1 of the excitation coil 121 is equal to Imax. If so, the current of the excitation coil 121 is kept at Imax, and the braking torque remains unchanged. If not, the current of the excitation coil 121 is first controlled to increase at a set rate. This increase in the current of the excitation coil 121 increases the vertical magnetic attraction, and the braking torque can then be controlled to increase at a preset rate, thereby increasing the braking torque. The maximum increase in braking torque from Tm is μ(Fzmax-Fz1)R, improving the braking effect and reducing the braking distance.

[0115] Specifically, when the aircraft 1 brakes, it is preferable to control any two adjacent excitation coils 121 to be energized with direct current in opposite directions, which generates a vertical magnetic attraction force Fz and a reverse magnetic force Fx. When the aircraft 1 is gliding (without braking), each excitation coil 121 is energized with alternating current, and the magnetic field moves at the same speed as the aircraft 1. Alternatively, each excitation coil 121 is energized with direct current in the same direction, primarily generating a vertical magnetic attraction force Fz.

[0116] Furthermore, it can be assumed that the vertical height of the electromagnetic actuator 12 remains constant when the aircraft 1 is moving. Of course, the vertical position of the electromagnetic actuator 12 can also be considered. With the current of the excitation coil 121 remaining constant, the closer the electromagnetic actuator 12 is to the field channel 3, the greater the electromagnetic force. At this time, the vertical magnetic attraction Fz is determined by the current of the excitation coil 121 and the height relative to the field channel 3.

[0117] In addition, the control method also includes:

[0118] Upon confirming receipt of the braking signal, the current I1 of the excitation coil 121 is acquired, and a braking torque Tm is provided, where Tm ≤ μ(F1 + Fz1)R. Here, μ is the coefficient of friction between the aircraft's wheels 1111 and the runway 3; F1 is the weight of the aircraft 1 (N); Fz1 is the vertical magnetic attraction force when the current in the excitation coil 121 is I1 (N); Fz1 ≥ 0, 0 ≤ I1 ≤ Imax; and R is the radius of the aircraft's wheels 1111 (m).

[0119] If a slippage signal is received, it is determined whether the current current I1 of the excitation coil 121 is equal to Imax, where Imax is the maximum value of the current of the excitation coil 121. If yes, the braking torque is controlled to decrease from Tm to Tn1. If no, the braking torque is controlled to decrease from Tm to Tn2, the current of the excitation coil 121 is controlled to increase at a set rate, and the braking torque is controlled to increase at a preset rate.

[0120] In other words, under braking conditions, if a slippage signal is received, it is determined whether the current I1 of the excitation coil 121 is equal to Imax. If the current I1 of the excitation coil 121 is equal to Imax, the braking torque is reduced to Tn1, which reduces the braking torque to prevent the wheels 1111 from locking up and improve the slippage problem. If the current I1 of the excitation coil 121 is less than Imax, the braking torque is first reduced to Tn2 to prevent the wheels 1111 from locking up and improve the slippage problem. Then, the current of the excitation coil 121 is increased at a set rate. At this time, the increase in vertical magnetic attraction allows the braking torque to increase, thus increasing the braking torque at a preset rate, which is beneficial for braking the aircraft 1. Among them, the current of the excitation coil 121 increases to a maximum of Imax, and the maximum increase in braking torque is (μ(Fzmax-Fz1)R).

[0121] It should be noted that the vertical height of the electromagnetic actuator 12 can be considered constant. Alternatively, the vertical position of the electromagnetic actuator 12 can also be considered. With the current of the excitation coil 121 remaining constant, the closer the electromagnetic actuator 12 is to the field channel 3, the greater the electromagnetic force. In this case, the vertical magnetic attraction Fz is determined by both the current of the excitation coil 121 and its height relative to the field channel 3.

[0122] Furthermore, if a braking signal is received but no slippage signal is received, the current of the excitation coil 121 is kept constant, thus maintaining the braking torque. Alternatively, the current of the excitation coil 121 can be reduced to zero at a set rate. In this case, the braking torque decreases as needed, but always maintains Tm ≤ μ(F1 + Fz1)R to prevent slippage. Here, Fz1 is the vertical magnetic attraction force when the current of the excitation coil 121 is I1, and I1 is the current of the excitation coil 121, which gradually decreases. When the current of the excitation coil 121 is zero, the maximum braking torque is (μF1R).

[0123] Figure 11 A flowchart of a control method for an aircraft in some embodiments of this application is shown.

[0124] See Figure 11 In some embodiments, when the moving speed of the aircraft 1 is greater than 0 m / s, the control method further includes:

[0125] The slippage signal has been received.

[0126] The system determines whether a braking signal is received. If a braking signal is received, the current braking torque Tm is obtained, and it is determined whether the current I1 of the excitation coil 121 is equal to Imax, where 0 ≤ I1 ≤ Imax. If yes, the braking torque is reduced from Tm to Tn1, where μ(F1 + Fzmax)R ≥ Tn1 ≥ μF1R. If no, the system sequentially reduces the control torque from Tm to Tn2, increases the current of the excitation coil 121 from I1 at a set rate, and increases the braking torque at a preset rate, with the maximum increase in braking torque from Tm being (μ(Fzmax - Fz1)R), where μ(F1 + Fz1)R ≥ Tn2 ≥ μF1R.

[0127] If no braking signal is received, and it is confirmed that the current of the excitation coil 121 is less than Imax, then the current of the excitation coil 121 is controlled to increase at a set rate.

[0128] Where Imax is the maximum current of excitation coil 121, A; μ is the coefficient of friction between the wheel 1111 of aircraft 1 and the runway 3; F1 is the weight of aircraft 1, N; Fzmax is the vertical magnetic attraction force when the current of excitation coil 121 is Imax, N; Fz1 is the vertical magnetic attraction force when the current of excitation coil 121 is I1, N; R is the radius of wheel 1111 of aircraft 1, m.

[0129] Understandably, when aircraft 1 receives a slippage signal while moving, there are two possibilities. One is that aircraft 1 is braking and slippage has occurred. In this case, the current braking torque Tm is obtained, and it is determined whether the current current I1 of the excitation coil 121 is equal to Imax. If so, the braking torque is reduced from Tm to Tn1, where μ(F1+Fzmax)R≥Tn1≥μF1R. This means that even though the braking torque is reduced due to slippage, the maximum value of the braking torque is still higher than if there were no vertical magnetic attraction Fx. Conversely, when the current I1 of the excitation coil 121 is less than Imax, the braking torque is first reduced to Tn2, and then the current of the excitation coil 121 is increased. With the increased current of the excitation coil 121, the braking torque is increased. This not only eliminates slippage but also increases the braking torque to brake aircraft 1 and reduce the braking distance. Where μ(F1+Fz1)R≥Tn2≥μF1R, the maximum value of the braking torque that can increase from Tn2 is μ(Fzmax-Fz1)R. That is to say, the current of the excitation coil 121 is I1, the vertical magnetic attraction force is Fz1, the current of the excitation coil 121 increases to Imax, and the vertical magnetic attraction force is Fzmax. Therefore, the maximum value that the braking torque can increase from Tn2 is μ(Fzmax-Fz1)R.

[0130] With the presence of a vertical magnetic attraction Fz, although the braking torque is reduced if slippage occurs during braking, the maximum value of the braking torque is still greater than in the case without the vertical magnetic attraction, which is beneficial for the braking of aircraft 1. Moreover, when the current of excitation coil 121 has not reached Imax, the braking torque can be reduced first to alleviate slippage. Subsequently, as the current of excitation coil 121 increases, the braking torque is increased, thus restoring the reduced braking torque to a certain extent, which is beneficial for the braking of aircraft 1. Furthermore, the presence of a reverse magnetic force Fx can also promote the deceleration of aircraft 1.

[0131] In other words, under braking conditions, to provide maximum braking torque, this electromagnetic auxiliary system can work in conjunction with the braking system of aircraft 1. When wheel 1111 slippage is detected, the braking system adjusts the braking torque through an algorithm based on data such as the contact force between wheel 1111 and the runway, dynamic parameters, and runway conditions to prevent wheel 1111 from locking up. At this time, the electromagnetic force is increased by increasing the current of the excitation coil 121. The reverse magnetic force Fx can directly participate in braking, while the vertical magnetic attraction force Fz can increase the friction between wheel 1111 and runway 3. The increase in friction can be fed back to the braking system, allowing the braking torque to be restored to a certain extent.

[0132] To prevent sudden electromagnetic force changes from impacting the runway 3 and the wheels 1111, the current in the excitation coil 121 increases or decreases at a set rate. This set rate is determined based on actual needs, such as the structure of the aircraft 1 and the load-bearing capacity of the runway 3. Similarly, the maximum current in the excitation coil 121 must not exceed the set maximum value Imax. Excessive current in the excitation coil 121 would generate excessive electromagnetic force, potentially damaging the structure of the aircraft 1 and the runway 3, affecting passenger comfort and the safety of both the aircraft 1 and the runway 3. Therefore, Imax is set according to actual needs, such as by comprehensively evaluating the load-bearing capacity of the aircraft 1 and the runway 3, and the actual current-electromagnetic force relationship.

[0133] Specifically, when the aircraft 1 brakes, it is preferable to control any two adjacent excitation coils 121 to be energized with direct current in opposite directions, which generates a vertical magnetic attraction force Fz and a reverse magnetic force Fx. When the aircraft 1 is gliding (without braking), each of the multiple excitation coils 121 is energized with alternating current, and the magnetic field moves at the same speed as the aircraft 1. Alternatively, each of the multiple excitation coils 121 is energized with direct current in the same direction, mainly generating a vertical magnetic attraction force Fz, in which case the reverse magnetic force Fx is small or negligible.

[0134] Another scenario is when the aircraft 1 does not brake upon receiving a skidding signal, such as during a taxiing turn. In this case, if no braking signal is received, the current I1 of the excitation coil 121 is less than Imax. The current of the excitation coil 121 is then increased at a set rate to increase the maximum friction between the aircraft 1 and the runway 3, thereby improving the skidding problem.

[0135] The technical features of the above embodiments can be combined in any way. For the sake of brevity, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0136] The embodiments described above are merely illustrative of several implementation methods of this application, and while the descriptions are relatively specific and detailed, they should not be construed as limiting the scope of the patent application. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of this application, and these all fall within the protection scope of this application. Therefore, the protection scope of this patent application should be determined by the appended claims.

Claims

1. An electromagnetic auxiliary system for an aircraft, characterized in that, The electromagnetic auxiliary system includes: Metal component (2) is disposed below the runway (3), which is configured for the aircraft to take off, land, taxi and park; An electromagnetic actuator (12) is disposed on the aircraft body (11) of the aircraft. The electromagnetic actuator (12) includes a plurality of excitation coils (121) arranged sequentially along the front end to the rear end of the aircraft body (11). The plurality of excitation coils (121) are configured to be energized to selectively generate a downward vertical magnetic attraction force together with the metal component (2), or to simultaneously generate a downward vertical magnetic attraction force and a reverse magnetic force opposite to the direction of movement of the aircraft. A lifting assembly (13) is connected to the electromagnetic actuator (12) and is used to connect to the aircraft body (11). The lifting assembly (13) is configured to drive the electromagnetic actuator (12) to lift in the vertical direction.

2. The electromagnetic auxiliary system for aircraft according to claim 1, characterized in that, The metal component (2) includes a metal mesh (21) and / or a metal plate (22).

3. The electromagnetic auxiliary system for aircraft according to claim 1, characterized in that, The airfield (3) includes a take-off and landing runway for the aircraft to take off and land; The metal component (2) includes a first metal part and a second metal part. The first metal part is closer to the landing runway than the second metal part, and the effective conductive area of ​​the first metal part is smaller than the effective conductive area of ​​the second metal part. The first metal part is a metal mesh (21) or a metal plate (22), and the second metal part is a metal mesh (21) or a metal plate (22).

4. An aircraft, characterized in that, It includes an aircraft body (11) and an electromagnetic actuator (12) and a lifting assembly (13) of an electromagnetic auxiliary system as described in any one of claims 1-3, wherein the lifting assembly (13) is disposed on the landing gear (111) of the aircraft body (11).

5. A control method for an electromagnetic auxiliary system for an aircraft as described in any one of claims 1-3, characterized in that, The control method includes: Confirm that the aircraft's moving speed is greater than 0 m / s; Determine whether a braking signal is received. If so, control any two adjacent excitation coils (121) to be supplied with direct current in opposite directions to generate a downward vertical magnetic attraction force and a reverse magnetic force opposite to the direction of movement of the aircraft. If not, then each of the plurality of excitation coils (121) is supplied with direct current in the same direction; or, each of the plurality of excitation coils (121) is supplied with alternating current, and the magnetic field moves at the same speed as the aircraft to generate a downward vertical magnetic attraction.

6. The control method for an electromagnetic auxiliary system for an aircraft according to claim 5, characterized in that, When the aircraft's moving speed is greater than 0 m / s, the control method further includes: If a braking signal is received, the lifting assembly (13) is controlled to drive the electromagnetic actuator (12) to descend to a first preset height; if no braking signal is received, the lifting assembly (13) is controlled to drive the electromagnetic actuator (12) to descend to a second preset height. When the aircraft is located in the airfield (3), the maximum height of the electromagnetic actuator (12) relative to the airfield (3) is Hmm, and both the first preset height and the second preset height are less than Hmm.

7. The control method for an electromagnetic auxiliary system for an aircraft according to claim 5, characterized in that, The control method further includes: Confirm that the aircraft's moving speed is equal to 0 m / s; The excitation coils (121) are energized to generate a downward vertical magnetic attraction.

8. The control method for an electromagnetic auxiliary system for an aircraft according to claim 7, characterized in that, When the aircraft's moving speed is 0 m / s, the control method further includes: Control the lifting assembly (13) to drive the electromagnetic actuator (12) to descend to a third preset height, or to descend to touch the field channel (3). When the aircraft is located in the airfield (3), the maximum height of the electromagnetic actuator (12) relative to the airfield (3) is Hmm, and the third preset height is less than Hmm.

9. A control method for an aircraft as described in claim 4, characterized in that, The aircraft has a braking system configured to provide braking torque. When the aircraft's moving speed is greater than 0 m / s, the control method includes: Upon confirming receipt of the braking signal, the current I1 (A) of the excitation coil (121) is obtained, and the braking torque Tm (N·m) is provided, where Tm ≤ μ(F1+Fz1)R, where μ is the coefficient of friction between the aircraft's wheels (1111) and the runway (3); F1 is the aircraft's own weight, N; Fz1 is the vertical magnetic attraction force when the current of the excitation coil (121) is I1, N, Fz1≥0, 0≤I1≤Imax; R is the radius of the aircraft's wheels (1111), m; Determine whether the current I1 of the excitation coil (121) is equal to Imax. If yes, keep the current of the excitation coil (121) at Imax. If no, control the current of the excitation coil (121) to increase at a set rate and control the braking torque to increase at a preset rate. The maximum value of the braking torque increasing from Tm is μ(Fzmax-Fz1)R. Wherein, Fzmax is the vertical magnetic attraction force when the current of the excitation coil (121) is Imax, N.

10. The control method for an aircraft according to claim 9, characterized in that, When the aircraft's moving speed is greater than 0 m / s, the control method further includes: Confirmation received of slippage signal; Determine whether a braking signal is received. If a braking signal is received, obtain the current control torque Tm (N·m) and determine whether the current current I1 of the excitation coil (121) is equal to Imax, where 0≤I1≤Imax; if yes, control the braking torque to decrease from Tm to Tn1, where μ(F1+Fzmax)R≥Tn1≥μF1R; if no, control the braking torque to decrease from Tm to Tn2, control the current of the excitation coil (121) to increase from I1 at a set rate, and control the braking torque to increase at a preset rate, and the maximum value of the braking torque to increase from Tm is μ(Fzmax-Fz1)R, where μ(F1+Fz1)R≥Tn2≥μF1R; If no braking signal is received, and it is confirmed that the current I1 of the excitation coil (121) is less than Imax, the current of the excitation coil (121) is controlled to increase at a set rate. Wherein, Imax is the maximum current of the excitation coil (121), A; μ is the friction coefficient between the aircraft's wheels (1111) and the runway (3); F1 is the aircraft's own weight, N; Fzmax is the vertical magnetic attraction force when the current of the excitation coil (121) is Imax, N; Fz1 is the vertical magnetic attraction force when the current of the excitation coil (121) is I1, N; R is the radius of the aircraft's wheels (1111), m.

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