A method and apparatus for generating overload commands based on glide slope deviation

Abstract

This disclosure relates to a method and apparatus for generating overload commands based on glide slope deviation. The method includes: generating a target vertical velocity based on the aircraft ground speed and the nominal glide slope angle; generating a vertical velocity deviation value based on the generated target vertical velocity and the aircraft's current vertical velocity; generating a vertical distance deviation value based on the aircraft's current radio altitude and the glide slope beam signal; generating a deviation vertical velocity estimate and a deviation vertical distance estimate based on the generated vertical velocity deviation value and the vertical distance deviation value; and generating a normal overload command based on the generated deviation vertical velocity estimate and deviation vertical distance estimate.

Description

Technical Field

[0001] This disclosure relates to the field of landing approach flight control, specifically to a method and apparatus for generating overload commands based on glide path deviation. Background Technology

[0002] Glide slope approach is a fundamental function required for all three types of landing. During the approach and landing, the glide slope angle and rate of descent are controlled by adjusting the pitch attitude and elevators to perform a five-way approach at a constant airspeed, ensuring the aircraft lands along the correct glide slope. The glide slope approach mode is crucial for ensuring a safe landing. Precise management of the aircraft's position and speed is required during the glide slope approach to ensure stable speed and attitude during the final approach phase. The glide slope angle and rate of descent are controlled by the pitch attitude and elevators. The optimal glide slope angle is typically set between 2.5° and 3° to ensure a smooth and accurate landing. Pilots need to closely monitor the aircraft's position and speed, as well as the glide slope angle, adjusting the aircraft's attitude as needed to maintain the correct glide slope angle.

[0003] However, conventional glide slope approach control methods directly control the glide slope deviation angle, and their control performance is significantly affected by the interception distance. Furthermore, these methods directly use the vertical velocity signal measured by sensors as input, resulting in poor robustness to sensor readings and significant susceptibility to altitude changes. In addition, conventional glide slope approach control methods rely on calculating the deviation angle using the glide slope beam signal acquired by sensors and an ILS (Instrument Landing System) model. This direct measurement method is susceptible to external factors such as altitude, terrain, and complex weather conditions, and the deviation angle calculation depends heavily on the accuracy of the ILS model.

[0004] Therefore, there is an urgent need for a method and equipment to further improve the existing glide slope approach control scheme. Summary of the Invention

[0005] This summary is provided to introduce, in a simplified form, some concepts that will be further described in the following detailed description section. This summary is not intended to identify key or essential features of the claimed subject matter, nor is it intended to help determine the scope of the claimed subject matter.

[0006] To address the problems in the prior art, this disclosure provides a method and apparatus for generating overload commands based on glide slope deviation. In the technical solution of this disclosure, the vertical velocity and vertical distance of the glide slope deviation can be estimated by synthesizing and filtering them. Furthermore, different weights can be assigned according to the aircraft altitude when estimating the vertical distance to obtain a more accurate estimate. This method enables the aircraft to land along a correct and accurate glide slope trajectory, which is crucial for ensuring a safe landing.

[0007] Specifically, in a first aspect of the present invention, a method for generating overload commands based on glide slope deviation is disclosed, the method comprising: The target vertical velocity is generated based on the aircraft's ground speed and nominal glide slope angle. A vertical speed deviation value is generated based on the target vertical speed and the aircraft's current vertical speed; The vertical distance deviation value is generated based on the aircraft's current radio altitude and glide slope beam signal; Based on the vertical velocity deviation value and the vertical distance deviation value, generate a deviation vertical velocity estimate and a deviation vertical distance estimate; and A normal overload command is generated based on the estimated vertical velocity and the estimated vertical distance of the deviation.

[0008] In one alternative implementation, the target vertical speed is calculated based on the aircraft ground speed and a trigonometric function with respect to the nominal glide slope angle, and the vertical speed deviation is obtained by subtracting the target vertical speed from the aircraft's current vertical speed.

[0009] In one alternative implementation, the glide slope beam signal indicates the glide slope deviation angle, and the vertical distance deviation value is calculated based on the glide slope deviation angle and the aircraft's current radio altitude.

[0010] In one alternative implementation, the deviation vertical velocity estimate is generated by complementary filtering and addition based on the vertical velocity deviation value and the vertical distance deviation value, and the deviation vertical distance estimate is generated by complementary filtering and subtraction based on the vertical velocity deviation value and the vertical distance deviation value.

[0011] In an alternative implementation, the deviation vertical velocity estimate is further generated by the following operation: The vertical velocity deviation value and the vertical distance deviation value are used to generate the deviation vertical velocity estimate using a high-pass filter and a differential filter, both of which have a first time constant.

[0012] In an optional implementation, the deviation vertical distance estimate is further generated by the following operation: At high altitude, based on the vertical velocity deviation value and the vertical distance deviation value, two low-pass filters with a first time constant are used to generate an estimated vertical distance value for the high-altitude deviation. At low altitude, based on the vertical velocity deviation value and the vertical distance deviation value, two low-pass filters with a second time constant greater than the first time constant are used to generate a low-altitude deviation vertical distance estimate; and The vertical distance estimate of the deviation is generated based on the upper-level deviation vertical distance estimate and the lower-level deviation vertical distance estimate, and by assigning appropriate weights. Low altitude and high altitude are determined by the aircraft's current radio altitude based on an altitude threshold, and the weight is dynamically adjusted based on the aircraft's current radio altitude.

[0013] In an alternative implementation, the normal overload command is further generated through the following operations: Assign the corresponding gain coefficients to the estimated vertical velocity of the deviation and the estimated vertical distance of the deviation, and then add them together; and The normal overload command is obtained by converting the total gain coefficient.

[0014] In a second aspect of the invention, an apparatus for generating overload commands based on glide slope deviation is disclosed, the apparatus comprising: The vertical speed deviation calculation module is configured to generate a target vertical speed based on the aircraft ground speed and the nominal glide slope angle, and to generate a vertical speed deviation value based on the target vertical speed and the aircraft's current vertical speed. The vertical distance deviation calculation module is configured to generate a vertical distance deviation value based on the aircraft's current radio altitude and glide slope beam signal; A deviation vertical velocity estimation module is configured to generate a deviation vertical velocity estimate based on the vertical velocity deviation value and the vertical distance deviation value; A deviation vertical distance estimation module, configured to generate a deviation vertical distance estimate based on the vertical velocity deviation value and the vertical distance deviation value; and A normal overload command generation module is configured to generate a normal overload command based on the estimated vertical velocity of the deviation and the estimated vertical distance of the deviation.

[0015] In an optional implementation, the vertical velocity deviation calculation module is further configured to: The target vertical velocity is calculated based on the aircraft's ground speed and a trigonometric function relating to the nominal glide slope angle; and The vertical speed deviation value is obtained by subtracting the target vertical speed from the current vertical speed of the aircraft.

[0016] In one alternative implementation, the glide slope beam signal indicates the glide slope deviation angle, and the vertical distance deviation calculation module is further configured to calculate the vertical distance deviation value based on the glide slope deviation angle and the aircraft's current radio altitude.

[0017] In an optional implementation, the deviation vertical velocity estimation module is further configured to generate the deviation vertical velocity estimate based on the vertical velocity deviation value and the vertical distance deviation value through complementary filtering and addition, and the deviation vertical distance estimation module is further configured to generate the deviation vertical distance estimate based on the vertical velocity deviation value and the vertical distance deviation value through complementary filtering and subtraction.

[0018] In an optional implementation, the deviation vertical velocity estimation module is further configured to: The vertical velocity deviation value and the vertical distance deviation value are used to generate the deviation vertical velocity estimate using a high-pass filter and a differential filter, both of which have a first time constant.

[0019] In an optional implementation, the deviation vertical distance estimation module is further configured to: At high altitude, based on the vertical velocity deviation value and the vertical distance deviation value, two low-pass filters with a first time constant are used to generate an estimated vertical distance value for the high-altitude deviation. At low altitude, based on the vertical velocity deviation value and the vertical distance deviation value, two low-pass filters with a second time constant greater than the first time constant are used to generate a low-altitude deviation vertical distance estimate; and The vertical distance estimate of the deviation is generated based on the upper-level deviation vertical distance estimate and the lower-level deviation vertical distance estimate, and by assigning appropriate weights. Low altitude and high altitude are determined by the aircraft's current radio altitude based on an altitude threshold, and the weight is dynamically adjusted based on the aircraft's current radio altitude.

[0020] In an optional implementation, the normal overload command generation module is further configured to generate the normal overload command by the following operations: Assign the corresponding gain coefficients to the estimated vertical velocity of the deviation and the estimated vertical distance of the deviation, and then add them together; and The normal overload command is obtained by converting the total gain coefficient.

[0021] In a third aspect of the invention, a computer-readable storage medium is disclosed, characterized in that the computer-readable storage medium stores instructions that, when executed, implement the method described in the first aspect.

[0022] Other aspects, features, and embodiments of the invention will become apparent to those skilled in the art after reading the following description of specific exemplary embodiments of the invention in conjunction with the accompanying drawings. Although features of the invention may be discussed below with reference to certain embodiments and drawings, all embodiments of the invention may include one or more of the advantageous features discussed herein. In other words, while one or more embodiments may be discussed having certain advantageous features, one or more of such features may also be used according to the various embodiments of the invention discussed herein. Similarly, although exemplary embodiments may be discussed below as embodiments of devices, apparatuses, or methods, it should be understood that such exemplary embodiments may be implemented in various devices, apparatuses, and methods. Attached Figure Description

[0023] To gain a more detailed understanding of the features described above in this disclosure, reference can be made to a more specific description of the above-briefly summarized aspects, some of which are illustrated in the accompanying drawings. However, it should be noted that the drawings illustrate only certain typical aspects of this disclosure and should not be considered as limiting its scope, as other equivalent aspects are permissible in this description.

[0024] Figure 1 This is a schematic block diagram of an apparatus for generating overload commands based on glide slope deviation, according to an embodiment of the present disclosure.

[0025] Figure 2 This is a logic diagram of glide path approach control according to an embodiment of the present disclosure.

[0026] Figure 3 This is an on / off logic diagram of a glide slope approach system according to an embodiment of the present disclosure; Figure 4 This is a flowchart of a method for generating overload commands based on glide slope deviation, according to an embodiment of the present disclosure.

[0027] Figure 5 This is a graph showing the change in aircraft overload command during glide path approach mode according to an embodiment of this disclosure.

[0028] Figure 6 This is a graph showing the change in aircraft signal relative to the glide slope beamband in a glide slope approach mode according to an embodiment of this disclosure.

[0029] Figure 7This is a graph showing the change in aircraft speed during glide slope approach mode according to an embodiment of the present disclosure.

[0030] Figure 8 This is a graph showing the glide slope approach mode engagement and aircraft altitude changes according to an embodiment of this disclosure. Detailed Implementation

[0031] The various embodiments will now be described in more detail with reference to the accompanying drawings, which form part of this invention and illustrate specific exemplary embodiments. However, the embodiments may be implemented in many different forms and should not be construed as limiting the embodiments set forth herein; rather, these embodiments are provided so that this disclosure will be thorough and complete, and will fully convey the scope of these embodiments to those skilled in the art. The embodiments may be implemented as methods, apparatus, or devices. Therefore, these embodiments may be implemented in hardware, entirely in software, or in a combination of software and hardware aspects. Therefore, the following detailed description is not intended to be limiting.

[0032] The steps in each flowchart can be performed by hardware (e.g., processor, engine, memory, circuitry), software (e.g., operating system, application, driver, machine / processor executable instructions), or a combination thereof. As will be understood by those skilled in the art, the methods involved in each embodiment may include more or fewer steps than shown.

[0033] To address the problems in existing technologies, such as the control performance being significantly affected by the interception distance, poor robustness to sensors, significant influence from altitude changes, susceptibility of direct measurement methods to external factors like altitude, terrain, and complex weather, and dependence of deviation angle calculation on the accuracy of the ILS model, and considering the crucial role of autopilot in modern civil aircraft fly-by-wire control laws, this invention aims to provide a method and device for generating overload commands based on glide slope deviation. This method enables the smooth interception and tracking of glide slope signals during automatic landing glide slope mode guidance and control, achieving the required control accuracy while minimizing overload variation (ΔNz).

[0034] The various aspects of the present invention will now be described in detail.

[0035] Figure 1 This is a schematic block diagram of an apparatus 100 for generating overload commands based on glide slope deviation, according to an embodiment of the present disclosure.

[0036] exist Figure 1In the illustrated embodiment, device 100 may include a vertical velocity deviation calculation module 102, a vertical distance deviation calculation module 104, a deviation vertical velocity estimation module 106, a deviation vertical distance estimation module 108, and a normal overload command generation module 110. The following will be combined with... Figure 2 The logic diagram of the glide slope approach control shown above describes each of the above modules in detail.

[0037] In the above embodiments, the vertical velocity deviation calculation module 102 can be configured to generate the target vertical velocity based on the aircraft ground speed and the nominal glide slope angle. In an optional implementation, such as Figure 2 As shown, the nominal glide slope angle (GlideSlope_norminal) can be ±3° or any other suitable glide slope angle and can be expressed as γ. The aircraft ground speed (in mps) can be communicated via the communication interface in device 100 (not shown in...). Figure 1 The target vertical velocity (as shown in the diagram) is received and can be represented as Vground, and the target vertical velocity can also be referred to as the ideal or given vertical velocity, which can be represented as Vzgiv. In this embodiment, the vertical velocity deviation calculation module 102 can be further configured to calculate the target vertical velocity Vzgiv based on the aircraft ground speed and a trigonometric function for the nominal glide slope angle.

[0038] In a non-restricted example, the target vertical velocity Vzgiv can be obtained by the following formula: Vzgiv = Vground × sin(γ), As those skilled in the art will understand, in other embodiments of this disclosure, the target vertical velocity can also be determined by any other suitable trigonometric function calculation method, not limited to the above-described method, and can also be determined by any other suitable method, not limited to trigonometric function calculation.

[0039] In the above embodiments, the vertical speed deviation calculation module 102 can also be configured to generate a vertical speed deviation value based on the generated target vertical speed and the aircraft's current vertical speed. In an optional embodiment, the aircraft's current vertical speed can also be received through a communication interface in the device 100, such as... Figure 2 As shown, the unit can be mps and can be represented as VzIRS. In this embodiment, the vertical speed deviation calculation module 102 can be further configured to obtain the vertical speed deviation value by subtracting the generated target vertical speed from the received current vertical speed of the aircraft. Figure 2 As shown, this vertical velocity deviation value can be expressed as delta_Vz, and can be determined by the following formula: delta_Vz = VzIRS – Vzgiv, As those skilled in the art will understand, the above-described method for calculating the vertical velocity deviation value is merely exemplary and not limiting. In other embodiments of this disclosure, any other suitable method may be used to determine the vertical velocity deviation value delta_Vz.

[0040] exist Figure 1 In the illustrated embodiment, the vertical distance deviation calculation module 104 can be configured to generate a vertical distance deviation value based on the aircraft's current radio altitude and glide slope beam signal. In an alternative embodiment, the aircraft's current radio altitude and glide slope beam signal can be received via a communication interface in device 100, such as... Figure 2 As shown, the unit of the aircraft's current radio altitude can be ft, which can be represented as RA; the glide slope beam signal can be represented as EGS, and can indicate the glide slope deviation angle; the vertical distance deviation value can be represented as delta_Z. In this embodiment, the vertical distance deviation calculation module 104 can be further configured to calculate the vertical distance deviation value based on the glide slope deviation angle and the aircraft's current radio altitude.

[0041] In a non-limiting example, the received glide slope deviation signal EGS can first be converted into an angle deviation Δγ (deg), then the angle can be converted to radians: Δγ_rad = Δγ × π / 180, and finally the vertical distance deviation value delta_Z can be determined by the following formula: delta_Z = RA×Δγ_rad, As those skilled in the art will understand, the method for calculating the vertical distance deviation value described above is merely exemplary and not restrictive. In other embodiments of this disclosure, any other suitable method may be used to determine the vertical distance deviation value delta_Z.

[0042] exist Figure 1 In the illustrated embodiment, the deviation vertical velocity estimation module 106 can be configured to generate a deviation vertical velocity estimate based on the generated vertical velocity deviation value and the vertical distance deviation value. In an alternative implementation, such as Figure 2 As shown, the deviation vertical velocity estimate can be represented as EST_delta_Vz, and the deviation vertical velocity estimation module 106 can be further configured to generate the deviation vertical velocity estimate based on the vertical velocity deviation value and the vertical distance deviation value through complementary filtering and addition. In this embodiment, the deviation vertical velocity estimation module 106 can also be further configured to generate the deviation vertical velocity estimate based on the vertical velocity deviation value and the vertical distance deviation value using a high-pass filter (e.g., one that can be used to preserve rapidly changing dynamic trends and suppress slow drift) and a differential filter, both having a first time constant.

[0043] In a non-limiting example, the estimated vertical velocity deviation of the aircraft relative to the glide slope can be generated by filtering out noise and disturbances using a complementary filter based on the vertical distance deviation value based on the glide slope deviation angle and the vertical velocity deviation value of the aircraft relative to the nominal glide slope of -3°, followed by physical addition. As an example and not a limitation, the complementary filtering can be performed using a high-pass filter with a time constant (i.e., a first time constant) of 5s and a differential filter with a time constant of 5s, or any other suitable filter. As those skilled in the art will understand, the value of the first time constant described above is merely exemplary and not limiting; any other suitable time constant can be used for complementary filtering, and the method of addition is not limited to any particular physical addition method, but can be any suitable addition method.

[0044] In one alternative implementation, such as Figure 2 As shown, a speed gain coefficient can be assigned to the generated vertical speed deviation estimate. By multiplying the generated vertical speed deviation estimate by a speed gain coefficient (which can be determined by a one-dimensional lookup table based on the aircraft's radio altitude RA), a corresponding control quantity is generated to control the aircraft to eliminate the glide slope speed deviation, thereby maintaining the aircraft's approach at different altitudes according to the vertical speed required by the nominal glide slope angle.

[0045] exist Figure 1 In the illustrated embodiment, the deviation vertical distance estimation module 108 can be configured to generate a deviation vertical distance estimate based on the vertical velocity deviation value and the vertical distance deviation value. In an optional implementation, such as Figure 2 As shown, the deviation vertical distance estimate can be represented as EST_delta_Z, and the deviation vertical distance estimation module 108 can also be configured to generate the deviation vertical distance estimate based on the vertical velocity deviation value and the vertical distance deviation value through complementary filtering and subtraction.

[0046] In one alternative implementation, considering the different interference experienced by the glide slope deviation signal during the approach process at high and low altitudes, the calculation of the vertical distance estimate of the aircraft's deviation relative to the glide slope is divided into a vertical distance estimate at high altitude and a vertical distance estimate at low altitude. These are distinguished by altitude and assigned different weights. The weight ratio can be dynamically adjusted according to the real-time altitude position of the aircraft (for example, the high-altitude vertical distance estimate is trusted more at high altitudes, and the low-altitude vertical distance estimate is trusted more at low altitudes). Since signals such as radio altitude signals and glide slope beam signals are subject to different interference and noise at different altitudes, filters with different time constants are required.

[0047] Therefore, as Figure 2As shown, the deviation vertical distance estimation module 108 can be further configured to: generate an upper-altitude deviation vertical distance estimate based on the vertical velocity deviation value and the vertical distance deviation value at high altitude using two low-pass filters with a first time constant (for example, not a limitation, but 5s, as described above) (e.g., used to retain slowly changing true deviations and filter out high-frequency jitter), and generate a lower-altitude deviation vertical distance estimate based on the vertical velocity deviation value and the vertical distance deviation value at low altitude using two low-pass filters with a second time constant greater than the first time constant (for example, not a limitation, but 10s).

[0048] In a non-limiting example, the vertical distance estimate at high altitude can be generated by complementary filtering of the vertical distance deviation based on the glide slope deviation angle and the vertical velocity deviation of the aircraft relative to the nominal glide slope of -3°. This complementary filtering can be performed, for example, by multiplying a low-pass filter with a time constant of 5s by a constant value of 5 and a low-pass filter with a time constant of 5s. The vertical distance estimate at low altitude can be generated by complementary filtering of the vertical distance deviation based on the glide slope deviation angle and the vertical velocity deviation of the aircraft relative to the nominal glide slope of -3°. This complementary filtering can be performed, for example, by multiplying a low-pass filter with a time constant (i.e., a second time constant) of 10s by a constant value of 10 and a low-pass filter with a time constant of 10s, assigning appropriate dynamic weights to both and subtracting them to obtain the estimated vertical distance deviation of the aircraft relative to the glide slope, i.e., the vertical distance estimate EST_delta_Z.

[0049] As will be understood by those skilled in the art, the first time constant, the second time constant, and the constant values ​​described above are exemplary and not limiting, and the method of subtraction is not limited to any particular method of subtraction, but any suitable method of subtraction can be used.

[0050] In one alternative implementation, such as Figure 2 As shown, a range gain coefficient can be assigned to the generated deviation vertical distance estimate. Then, by multiplying the generated deviation vertical distance estimate by a range gain coefficient (which can be determined by a one-dimensional lookup table (LOOKUP 1D) based on the aircraft's radio altitude RA), a corresponding control quantity is generated to control the aircraft to eliminate glide path distance deviation.

[0051] As those skilled in the art will understand, low and high altitudes can be determined using the aircraft's current radio altitude (RA) based on altitude thresholds, and the weights are dynamically adjusted according to the aircraft's current radio altitude. Adjustment criteria could include, for example, placing greater trust in the high-altitude deviation vertical distance estimate and assigning it a larger weight proportion at high altitudes, and placing greater trust in the low-altitude deviation vertical distance estimate and assigning it a larger weight proportion at low altitudes. As those skilled in the art will understand, the aforementioned altitude thresholds are not limited to any specific threshold, but can be set according to actual needs, and therefore can be any suitable altitude threshold. Similarly, the weight values ​​(e.g., proportions) are not limited to any specific value, but can be set according to actual needs, and therefore can be any suitable weight value.

[0052] exist Figure 1 In the illustrated embodiment, the normal overload command generation module 110 can be configured to generate a normal overload command based on the deviation vertical velocity estimate and the deviation vertical distance estimate. In an optional embodiment, such as Figure 2 As shown, the normal overload command generation module 110 can also be configured to add the generated deviation vertical velocity estimate and deviation vertical distance estimate into a command, and convert the result through a total gain coefficient to obtain the normal overload command NzCMD_GS, ​​in g, to control the aircraft to complete the approach along the actual glide path. As those skilled in the art will understand, the method of command addition is not limited to any specific addition method, but any suitable command addition method can be used.

[0053] In one exemplary embodiment of this disclosure, Figure 1 The device 100 shown may also include a computer-readable storage medium (not shown) for storing the received current vertical speed of the aircraft, the aircraft ground speed, the glide slope beam signal, the current radio altitude of the aircraft, and the generated target vertical speed, vertical speed deviation value, vertical distance deviation value, deviation vertical speed estimate, deviation vertical distance estimate, normal overload command, and instructions for performing the operations of the various modules in the device 100.

[0054] Figure 3 This is a connection logic diagram of a glide slope approach system according to an embodiment of the present disclosure.

[0055] Once the glide path approach mode is pre-positioned, the aircraft should begin intercepting the glide path before intersecting with the glide path trajectory. In approach mode, the following conditions are used to detect whether glide path interception has begun.

[0056] like Figure 3 As shown, 1 represents the relative position conditions when the aircraft approaches the glide path, specifically divided into the following two cases: 1) When an aircraft approaches the glide path from above, the following conditions must be met: 0 < εgl ​​<εgl_above & NzCMD_GS >0 2) When an aircraft approaches the glide path from below, the following conditions must be met: εgl_below < εgl ​​≤ 0 & NzCMD_GS≤0 Wherein, εgl is the glide slope beamband signal (i.e., the indicated glide slope beamband current value), which is acquired by the inertial and navigation system data sensors, and εgl_above and εgl_below are given glide slope angle limit values, which are obtained according to the radio altitude parameter tuning, and the unit is DDM; NzCMD_GS is the value of the normal overload instruction, in grams (g).

[0057] Its judgment logic is that as long as either of the two conditions is met, then condition 1 is met; 2 is the activation mode switch signal condition. When the approach pre-position mode is activated, condition 2 is satisfied. Condition 3 refers to the heading and track deviation conditions at the time of connection. Condition 3 is satisfied when the aircraft's lateral track has entered the linear zone of the heading beacon and the difference between the aircraft's heading and the runway heading is less than or equal to Delta_r. Delta_r is the deviation angle between the aircraft's heading and the runway's heading. It is calculated by the aircraft's inertial data and navigation data through the localizer approach control system, and the unit is deg. 4 is the logic "AND" judgment module, which means that conditions 1, 2, and 3 must be met simultaneously for the output to be "true"; 5 is a signal latch. When the input is true, the signal at that moment is latched. The purpose of latching is to prevent interruption once the connection condition is met, until the glide slope approach process is completed. 6 is the output logic signal for enabling the glide slope approach function. A signal of "1" indicates that the function is enabled, and "0" indicates that the function is not enabled.

[0058] Figure 4 This is a flowchart of a method 400 for generating overload commands based on glide slope deviation, according to an embodiment of the present disclosure.

[0059] like Figure 4 As shown, method 400 begins at step 402, generating a target vertical velocity based on the aircraft ground speed and the nominal glide slope angle. In an alternative implementation, the target vertical velocity may be calculated based on the aircraft ground speed and a trigonometric function with respect to the nominal glide slope angle.

[0060] Next, method 400 may continue to step 404, generating a vertical speed deviation value based on the target vertical speed and the aircraft's current vertical speed. In an optional implementation, the vertical speed deviation value may be obtained by subtracting the target vertical speed from the aircraft's current vertical speed.

[0061] Then, method 400 may continue to step 406, generating a vertical distance deviation value based on the aircraft's current radio altitude and the glide slope beam signal. In an alternative embodiment, the glide slope beam signal may indicate a glide slope deviation angle, and the vertical distance deviation value may be calculated based on the glide slope deviation angle and the aircraft's current radio altitude.

[0062] Next, method 400 may continue to step 408, generating a deviation vertical velocity estimate and a deviation vertical distance estimate based on the vertical velocity deviation value and the vertical distance deviation value. In an optional embodiment, the deviation vertical velocity estimate is generated by complementary filtering and addition based on the vertical velocity deviation value and the vertical distance deviation value, and the deviation vertical distance estimate is generated by complementary filtering and subtraction based on the vertical velocity deviation value and the vertical distance deviation value. In the above embodiment, the deviation vertical velocity estimate is also generated by using a high-pass filter and a differential filter, both having a first time constant, based on the vertical velocity deviation value and the vertical distance deviation value. In the above embodiments, the deviation vertical distance estimate is further generated through the following operations: at high altitude, a high-altitude deviation vertical distance estimate is generated using two low-pass filters with a first time constant based on the vertical speed deviation value and the vertical distance deviation value; at low altitude, a low-altitude deviation vertical distance estimate is generated using two low-pass filters with a second time constant greater than the first time constant based on the vertical speed deviation value and the vertical distance deviation value; and the deviation vertical distance estimate is generated based on the high-altitude deviation vertical distance estimate and the low-altitude deviation vertical distance estimate by assigning corresponding weights, wherein low altitude and high altitude are determined by the aircraft's current radio altitude according to an altitude threshold, and the weights are dynamically adjusted according to the aircraft's current radio altitude.

[0063] Finally, method 400 may continue to step 410, generating a normal overload command based on the deviation vertical velocity estimate and the deviation vertical distance estimate. In an optional embodiment, the normal overload command is further generated by: assigning corresponding gain coefficients to the deviation vertical velocity estimate and the deviation vertical distance estimate and adding them together; and obtaining the normal overload command through a total gain coefficient conversion.

[0064] After step 410, method 400 ends.

[0065] the following Figures 5 to 8 The simulation analysis results are shown when the technical solution of this disclosure is adopted.

[0066] Figure 5 This is a graph showing the change in aircraft overload command during glide path approach mode according to an embodiment of this disclosure.

[0067] like Figure 5 As shown, the red and black dashed lines represent the accuracy range of the overload command control (the black dashed line is the lower limit of the overload limit range drawn according to design requirements, and the red dashed line is the upper limit of the overload limit range drawn according to design requirements). When the aircraft is in level flight after trimming, the overload command is 0, and the unit is g. The maximum overload command change is set to |ΔNz|=0.15, so the control range of the overload command is -0.15 to +0.15, as shown by the red and black dashed lines. The magenta line is the overload command calculated by the glide slope approach mode (the overload command obtained by the traditional method), and the green line is the overload command output by the final automatic flight control law (the overload command obtained by the method of this invention). The maximum overload command output during glide slope interception is 0.02g, and it is stable at 0g during glide slope tracking. It can be seen that the overload change is small and the rate of change is slow during glide slope interception and tracking, the transition process is smooth, and it is ultimately maintained within the required accuracy range.

[0068] Figure 6 This is a graph showing the change in aircraft signal relative to the glide slope beamband in a glide slope approach mode according to an embodiment of this disclosure.

[0069] like Figure 6 As shown, the black dashed line represents the overshoot and tracking limit range of the glide slope beam signal according to conventional design requirements (i.e., the threshold range within which glide slope beam ripple cannot exceed), while the red dashed line represents the overshoot and tracking limit range of the glide slope beam signal according to higher design standards (i.e., the threshold range within which glide slope beam ripple cannot exceed). It can be seen that during the aircraft's level flight and automatic acquisition of the glide slope, the beam segment signal relative to the glide slope exhibits no overshoot or oscillation; the acquisition process is rapid and stable, ultimately maintaining within the required accuracy range.

[0070] Figure 7 This is a graph showing the change in aircraft speed during glide slope approach mode according to an embodiment of the present disclosure.

[0071] like Figure 7As shown, the magenta dashed line represents the given calibration airspeed, the blue solid line represents the calibration airspeed, and the black dashed line represents the speed limit range drawn according to design requirements (i.e., the threshold range within which speed fluctuations cannot exceed). It can be seen that during the glide slope interception process, the maximum overshoot relative to the initial trim speed of 145 kN is 0.6 kN. The speed change is small, the rate of change is slow, there is no overshoot, and it ultimately remains within the required accuracy range.

[0072] Figure 8 This is a graph showing the glide slope approach mode engagement and aircraft altitude changes according to an embodiment of this disclosure.

[0073] like Figure 8 As shown in the chart above, the glide slope approach mode engagement status is illustrated, where 1 indicates sub-mode engagement and 0 indicates sub-mode disengagement. The solid green line represents the glide slope mode, and the solid black line represents the localizer mode. In the chart below, the solid blue line represents the actual output altitude value, and the dashed red line represents the virtual glide slope range drawn based on the nominal glide slope and control requirements. It can be seen that upon intercepting the glide slope, the flight trajectory transitions from level flight to a -3° glide without overshoot, ultimately remaining within the required accuracy range.

[0074] In summary, compared to existing control methods based on glide slope deviation angles, the glide slope approach mode elevator channel control method of this invention employs a control method based on the estimated glide slope deviation distance and the estimated vertical velocity relative to the glide slope, which greatly improves performance and enhances system robustness. It enables smooth interception and tracking of glide slope signals during automatic landing glide slope mode guidance and control, improves control accuracy, minimizes overload variations, and enhances passenger comfort.

[0075] The embodiments of the present invention have been described above with reference to block diagrams and / or operational descriptions of methods and apparatus according to embodiments of the present invention. The functions / actions indicated in the blocks may appear in a different order than shown in any flowchart. For example, depending on the functions / actions involved, two blocks shown consecutively may actually be executed substantially simultaneously, or these blocks may sometimes be executed in reverse order.

[0076] The above description is merely a preferred embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any variations or substitutions that can be easily conceived by those skilled in the art within the technical scope disclosed in the present invention should be included within the scope of protection of the present invention. Therefore, the scope of protection of the present invention should be determined by the scope of the claims.

Claims

1. A method for generating overload commands based on glide slope deviation, the method comprising: The target vertical velocity is generated based on the aircraft's ground speed and nominal glide slope angle. A vertical speed deviation value is generated based on the target vertical speed and the aircraft's current vertical speed; The vertical distance deviation value is generated based on the aircraft's current radio altitude and glide slope beam signal; Based on the vertical velocity deviation value and the vertical distance deviation value, generate a deviation vertical velocity estimate and a deviation vertical distance estimate; and A normal overload command is generated based on the estimated vertical velocity and the estimated vertical distance of the deviation.

2. The method according to claim 1, characterized in that, The target vertical speed is calculated based on the aircraft's ground speed and a trigonometric function with respect to the nominal glide slope angle, and the vertical speed deviation is obtained by subtracting the target vertical speed from the aircraft's current vertical speed.

3. The method according to claim 1, characterized in that, The glide slope beam signal indicates the glide slope deviation angle, and the vertical distance deviation value is calculated based on the glide slope deviation angle and the aircraft's current radio altitude.

4. The method according to claim 1, characterized in that, The deviation vertical velocity estimate is generated by complementary filtering and addition based on the vertical velocity deviation value and the vertical distance deviation value, and the deviation vertical distance estimate is generated by complementary filtering and subtraction based on the vertical velocity deviation value and the vertical distance deviation value.

5. The method according to claim 4, characterized in that, The estimated vertical velocity deviation is also generated through the following operations: The vertical velocity deviation value and the vertical distance deviation value are used to generate the deviation vertical velocity estimate using a high-pass filter and a differential filter, both of which have a first time constant.

6. The method according to claim 4, characterized in that, The estimated vertical distance deviation is also generated through the following operations: At high altitude, based on the vertical velocity deviation value and the vertical distance deviation value, two low-pass filters with a first time constant are used to generate an estimated vertical distance value for the high-altitude deviation. At low altitude, based on the vertical velocity deviation value and the vertical distance deviation value, two low-pass filters with a second time constant greater than the first time constant are used to generate a low-altitude deviation vertical distance estimate; and The vertical distance estimate of the deviation is generated based on the upper-level deviation vertical distance estimate and the lower-level deviation vertical distance estimate, and by assigning appropriate weights. Low altitude and high altitude are determined by the aircraft's current radio altitude based on an altitude threshold, and the weight is dynamically adjusted based on the aircraft's current radio altitude.

7. The method according to claim 1, characterized in that, The normal overload command is also generated through the following operations: Assign the corresponding gain coefficients to the estimated vertical velocity of the deviation and the estimated vertical distance of the deviation, and then add them together; as well as The normal overload command is obtained by converting the total gain coefficient.

8. An apparatus for generating overload commands based on glide slope deviation, the apparatus comprising: The vertical speed deviation calculation module is configured to generate a target vertical speed based on the aircraft ground speed and the nominal glide slope angle, and to generate a vertical speed deviation value based on the target vertical speed and the aircraft's current vertical speed. The vertical distance deviation calculation module is configured to generate a vertical distance deviation value based on the aircraft's current radio altitude and glide slope beam signal; A deviation vertical velocity estimation module is configured to generate a deviation vertical velocity estimate based on the vertical velocity deviation value and the vertical distance deviation value; A deviation vertical distance estimation module is configured to generate a deviation vertical distance estimate based on the vertical velocity deviation value and the vertical distance deviation value; as well as A normal overload command generation module is configured to generate a normal overload command based on the estimated vertical velocity of the deviation and the estimated vertical distance of the deviation.

9. The device according to claim 8, characterized in that, The vertical velocity deviation calculation module is further configured to: The target vertical velocity is calculated based on the aircraft's ground speed and a trigonometric function relating to the nominal glide slope angle; and The vertical speed deviation value is obtained by subtracting the target vertical speed from the current vertical speed of the aircraft.

10. The device according to claim 8, characterized in that, The glide slope beam signal indicates the glide slope deviation angle, and the vertical distance deviation calculation module is further configured to calculate the vertical distance deviation value based on the glide slope deviation angle and the aircraft's current radio altitude.

11. The device according to claim 8, characterized in that: The deviation vertical velocity estimation module is further configured to generate the deviation vertical velocity estimate based on the vertical velocity deviation value and the vertical distance deviation value through complementary filtering and addition; and The deviation vertical distance estimation module is further configured to generate the deviation vertical distance estimate based on the vertical velocity deviation value and the vertical distance deviation value through complementary filtering and subtraction.

12. The device according to claim 11, characterized in that, The deviation vertical velocity estimation module is further configured to: The vertical velocity deviation value and the vertical distance deviation value are used to generate the deviation vertical velocity estimate using a high-pass filter and a differential filter, both of which have a first time constant.

13. The device according to claim 11, characterized in that, The deviation vertical distance estimation module is further configured to: At high altitude, based on the vertical velocity deviation value and the vertical distance deviation value, two low-pass filters with a first time constant are used to generate an estimated vertical distance value for the high-altitude deviation. At low altitude, based on the vertical velocity deviation value and the vertical distance deviation value, two low-pass filters with a second time constant greater than the first time constant are used to generate a low-altitude deviation vertical distance estimate; and The vertical distance estimate of the deviation is generated based on the upper-level deviation vertical distance estimate and the lower-level deviation vertical distance estimate, and by assigning appropriate weights. Low altitude and high altitude are determined by the aircraft's current radio altitude based on an altitude threshold, and the weight is dynamically adjusted based on the aircraft's current radio altitude.

14. The device according to claim 8, characterized in that, The normal overload command generation module is further configured to generate the normal overload command through the following operations: Assign the corresponding gain coefficients to the estimated vertical velocity of the deviation and the estimated vertical distance of the deviation, and then add them together; as well as The normal overload command is obtained by converting the total gain coefficient.

15. A computer-readable storage medium, characterized in that, The computer-readable storage medium stores instructions that, when executed, implement the method of any one of claims 1-7.

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