A redundancy actuation system channel switching method

Abstract

The application provides a redundancy actuation system channel switching method, comprising the following steps: establishing a flight control model of an aircraft; determining a response performance optimization form according to the flight control model; determining an upper limit of the flight control model response; modeling the redundancy actuation system of the system; determining a quantitative value of the influence of a switching threshold on a flight control response performance index; setting a quantitative increment of a response performance index caused by a redundancy actuation system fault switching threshold delta to zero, determining a quantitative value of the influence of a fault allowable response time on the flight control response performance index; determining the value range of the redundancy actuation system fault switching threshold delta and the redundancy actuation system fault allowable response time delta t under different disturbances; and determining the redundancy actuation system channel switching method under different error duration and external disturbance input. The application guarantees the effective switching of the redundancy actuation system under the current channel serious fault, the controllable transient characteristics of the aircraft and the good flight quality.

Description

Technical Field

[0001] This invention belongs to the field of fault-tolerant control and flight quality optimization technology, specifically relating to a channel switching method for a redundancy actuation system. Background Technology

[0002] To further enhance reliability, the aerospace industry is placing increasingly higher demands on the fault tolerance of control systems, especially in large civil aircraft and unmanned aerial vehicles (UAVs) requiring high reliability and ultra-long endurance. Ensuring the success rate of flight missions under harsh conditions places even greater demands on the performance and decision-making efficiency of fault-tolerant control systems. Redundant actuation systems, due to their ability to switch channels after a failure and to achieve fault-tolerant reconfiguration, are increasingly being applied to various high-value aircraft.

[0003] However, there is no clear criterion for channel switching in redundant actuation systems. If the channel switching conditions are too lenient after a system failure, the switching may be too delayed, which will affect the transient characteristics and control quality of the flight control system and even lead to catastrophic consequences. If the channel switching conditions are too strict, the actuation system may switch ineffectively under interference, wasting redundancy resources and fault tolerance potential. Therefore, it is of great significance to optimize the channel switching judgment criteria of redundant actuation systems. Summary of the Invention

[0004] The purpose of this invention is to overcome the shortcomings of the prior art and provide a channel switching method for a redundancy actuation system. The solution of this invention can solve the problems existing in the prior art.

[0005] The technical solution of this invention:

[0006] According to the first aspect, a channel switching method for a redundancy actuation system is provided, comprising the following steps:

[0007] Based on the pitch, roll, and yaw functions of the aircraft, which are determined by the elevator, aileron, and rudder respectively, a flight control state space model (hereinafter referred to as the flight control model) is established.

[0008] Determine the optimization form of response performance indicators based on the flight control model;

[0009] Determine the quantitative upper bound of the flight control model response performance index;

[0010] The redundant actuation system is used as the input to the flight control model, and the attitude angle controlled by the actuation system is used as the model output. The redundant actuation system components of the system are modeled.

[0011] Based on the input of the flight control model and the fault switching threshold δ of the redundant actuation system, the quantitative value of the impact of the switching threshold on the flight control response performance index is determined under the condition that rapid switching is required for sudden faults.

[0012] Based on the input of the flight control model and the fault tolerance response time Δt of the redundancy actuation system, for the slowly changing performance degradation type fault of the redundancy actuation system, since this type of fault will not cause it to reach the switching threshold δ in a short time, the quantitative increment of the response performance index caused by the fault switching threshold δ of the redundancy actuation system will be set to zero, thereby determining the quantitative value of the impact of the cumulative effect of the fault tolerance response time on the flight control response performance index.

[0013] Based on the upper bound of the flight control model response obtained under different external disturbances, the quantitative value of the impact of the switching threshold on the flight control response performance index, and the quantitative value of the impact of the fault tolerance response time on the flight control response performance index, the range of values ​​for the fault switching threshold δ of the redundancy actuation system and the fault tolerance response time Δt of the redundancy actuation system under different disturbances is determined. The upper bound of the flight control model response is used as the index optimization term to form the channel switching criterion.

[0014] The index function form of flight control response is affected by the duration of error and the amount of external interference input. Based on the redundancy actuation system channel switching criteria, the redundancy actuation system channel switching method is determined for different error durations and external interference inputs.

[0015] Furthermore, the aforementioned aircraft flight control state space model is as follows:

[0016]

[0017] Where, x aug (t)=[x(t) ∫e(t)dt] T y aug (t)=[y(t) ∫e(t)dt] T w aug (t)=[w(t) r(t)] T The state variable x(t) = [β pr φ] T Where β is the sideslip angle, p is the roll rate, r is the yaw rate, φ is the roll angle, and e(t) = r(t) - S out y(t) and e(t) are response errors, r(t) is the flight control command, w(t) is external interference, and S out y(t) represents the attitude angle output by the flight control model, y(t) = Cx(t), and the corresponding coefficient matrix is... In the flight control model, the input form of the control surface deflection angle is u(t)=[δ ain δ aout δ sp δ rup δ rlow ] T , where δ ainand δ aout The inputs are the deflection angles of the inner and outer ailerons, δ. sp The deflection angle input for the spoiler is δ. rup and δ rlow These are the deflection angles of the up and down rudders, respectively, where A is the linearized parameter matrix of the pre-augmented flight control model, and B... f For the control gain matrix, C f G is the full-state output matrix, G is the disturbance term matrix, and S is the full-state output matrix. out This is the attitude angle output matrix.

[0018] Furthermore, the redundant actuation system model is as follows:

[0019] Where δ is the out-of-tolerance threshold of the redundant actuation system; u sys For the system-level input of the actuation system; u A For the A channel input of the actuation system; u B This is the B channel input for the actuation system; The input for a fault-free and normal response in channel A of the redundancy actuation system; For the redundancy actuation system, channel B has a fault-free normal response input; t begin-fault The moment when the response of channel A of the redundancy actuation system begins to reach the switching threshold; t after-fault The moment when the redundancy actuation system's B channel successfully switches and begins to eliminate fault threshold deviations.

[0020] Furthermore, the optimized form of the flight control model response performance is an LQ quadratic form. in For the controller of the flight control model, K = [K x K e To control the gain, and These are the weight matrices for the augmented state vector and input vector of the flight control model, respectively, where Q... x Q is the augmented pre-state vector. e To augment the integral term of the error before the expansion, R x Before augmentation, the input vector R e Let P be the weight matrix of the unaugmented correlation error vector, and let P be the solution matrix of the control gain of the Riccati equation.

[0021] Furthermore, the upper bound of the flight control model response is Among them, P c It is a positive definite symmetric matrix, and γ is the perturbation suppression coefficient.

[0022] Furthermore, the quantitative value of the impact of the switching threshold on the flight control response performance index is as follows: e(δ(t)) is the state vector error term caused by the switching threshold.

[0023] Furthermore, the quantitative value of the impact of fault tolerance response time on flight control response performance indicators is as follows:

[0024] Furthermore, (∫e(τ)dt)Q e (∫e(τ)dt)=b, the formulas for determining the range of values ​​for the redundancy actuation system fault switching threshold δ and the redundancy actuation system fault tolerance response time Δt under different disturbances are: Where, λ 2 ||w|| 2 =w T (τ)G T Gw(τ), where λ is the spectral radius of matrix G.

[0025] Furthermore, the channel switching criteria for the redundancy actuation system are as follows:

[0026] The criterion for determining the maximum permissible time for channel switching in a redundancy actuation system is that when the external interference w is bounded, w has an upper bound on its norm ||w||. max At this point, the allowable response time reaches its maximum value (Δt). max Within this time, the switching is smooth; when the external interference is a pulse-type interference, w has no upper bound of norm for a short period of time. At this time, the redundancy actuation system faces extreme conditions and the redundancy actuation system performs transient switching; regarding the criteria for judging the maximum switching threshold of the redundancy actuation system, when the value of the flight control model response is determined, the shorter the duration of the error of the actuation system within the critical value, the larger its out-of-tolerance threshold setting is.

[0027] According to the second aspect, a redundancy actuation system is provided, wherein the redundancy actuation system uses the redundancy actuation system channel switching method described above to switch the redundancy actuation system.

[0028] According to the second aspect, an aircraft is provided, wherein the aircraft is equipped with the redundancy actuation system described above.

[0029] The beneficial effects of this invention compared to the prior art are as follows:

[0030] This invention optimizes the channel switching criteria of the redundancy actuation system by determining the range of values ​​for the fault switching threshold δ and the fault tolerance response time Δt of the redundancy actuation system. This avoids invalid switching and waste of fault tolerance resources caused by overly stringent switching conditions, while ensuring effective switching of the redundancy actuation system when the current channel is severely faulty, as well as the controllable transient characteristics and good flight quality of the aircraft. Attached Figure Description

[0031] The accompanying drawings, which form part of this specification, are provided to further illustrate embodiments of the invention and, together with the textual description, explain the principles of the invention. It is obvious that the drawings described below are merely some embodiments of the invention, and those skilled in the art can obtain other drawings based on these drawings without any creative effort.

[0032] Figure 1 A flowchart of the channel switching discrimination criterion for a redundancy actuation system provided according to an embodiment of the present invention is shown;

[0033] Figure 2 This diagram illustrates the principle of calculating the LQ quadratic quantization index value of the flight control model response according to an embodiment of the present invention.

[0034] Figure 3 This diagram illustrates the implementation architecture of the channel switching discrimination criterion for a redundant actuation system provided according to an embodiment of the present invention.

[0035] Figure 4 A schematic diagram of simulation results provided according to an embodiment of the present invention is shown. Detailed Implementation

[0036] It should be noted that, unless otherwise specified, the embodiments and features described in this application can be combined with each other. The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of the present invention, and not all of them. The following description of at least one exemplary embodiment is merely illustrative and is in no way intended to limit the present invention or its application or use. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0037] It should be noted that the terminology used herein is for the purpose of describing particular embodiments only and is not intended to limit the exemplary embodiments according to this application. As used herein, the singular form is intended to include the plural form as well, unless the context clearly indicates otherwise. Furthermore, it should be understood that when the terms "comprising" and / or "including" are used in this specification, they indicate the presence of features, steps, operations, devices, components, and / or combinations thereof.

[0038] Unless otherwise specifically stated, the relative arrangement, numerical expressions, and values ​​of the components and steps set forth in these embodiments do not limit the scope of the invention. It should also be understood that, for ease of description, the dimensions of the various parts shown in the drawings are not drawn to actual scale. Techniques, methods, and devices known to those skilled in the art may not be discussed in detail, but where appropriate, such techniques, methods, and devices should be considered part of the specification. In all examples shown and discussed herein, any specific values ​​should be interpreted as merely exemplary and not as limitations. Therefore, other examples of exemplary embodiments may have different values. It should be noted that similar reference numerals and letters in the following figures denote similar items; therefore, once an item is defined in one figure, it need not be further discussed in subsequent figures.

[0039] According to an embodiment of the present invention, a channel switching method for a redundancy actuation system is provided, comprising the following steps:

[0040] Based on the pitch, roll, and yaw functions of the aircraft, which are determined by the elevator, aileron, and rudder respectively, a flight control state space model (hereinafter referred to as the flight control model) is established.

[0041] Determine the optimization form of the flight control model response performance index based on the flight control model;

[0042] Determine the quantitative upper bound of the flight control model response performance index;

[0043] The redundant actuation system is used as the input to the flight control model, and the attitude angle controlled by the actuation system is used as the model output. The redundant actuation system components of the system are modeled.

[0044] Based on the input of the flight control model and the fault switching threshold δ of the redundant actuation system, the quantitative value of the impact of the switching threshold on the flight control response performance index is determined under the condition that rapid switching is required for sudden faults.

[0045] Based on the input of the flight control model and the fault tolerance response time Δt of the redundancy actuation system, for the slowly changing performance degradation type fault of the redundancy actuation system, since this type of fault will not cause it to reach the switching threshold δ in a short time, the quantitative increment of the response performance index caused by the fault switching threshold δ of the redundancy actuation system will be set to zero, thereby determining the quantitative value of the impact of the cumulative effect of the fault tolerance response time on the flight control response performance index.

[0046] Based on the upper bound of the flight control model response obtained under different external disturbances, the quantitative value of the impact of the switching threshold on the flight control response performance index, and the quantitative value of the impact of the fault tolerance response time on the flight control response performance index, the range of values ​​for the fault switching threshold δ of the redundancy actuation system and the fault tolerance response time Δt of the redundancy actuation system under different disturbances is determined. The upper bound of the flight control model response is used as the index optimization term to form the channel switching criterion.

[0047] The index function form of flight control response is affected by the duration of error and the amount of external interference input. Based on the redundancy actuation system channel switching criteria, the redundancy actuation system channel switching method is determined for different error durations and external interference inputs.

[0048] By applying this setting, the upper bound of the flight control model response is set, and the range of values ​​for the redundancy actuation system fault switching threshold δ and the redundancy actuation system fault tolerance response time Δt under different disturbances is determined. Thus, based on the redundancy actuation system channel switching criteria, it is determined whether to perform channel switching. This avoids invalid switching and waste of fault tolerance resources caused by overly stringent switching conditions, while ensuring effective switching of the redundancy actuation system when the current channel is severely faulty, as well as the controllable transient characteristics and good flight quality of the aircraft.

[0049] In another embodiment, the aircraft control state-space formal model is as follows:

[0050] Where, xaug(t)=[x(t) ∫e(t)dt] T y aug (t)=[y(t) ∫e(t)dt] T w aug (t)=[w(t) r(t)] T The state variable x(t) = [β p rφ] T Where β is the sideslip angle, p is the roll rate, r is the yaw rate, φ is the roll angle, and e(t) = r(t) - S out y(t) and e(t) are response errors, r(t) is the flight control command, w(t) is external interference, and S out y(t) represents the attitude angle output by the flight control model, y(t) = Cx(t), and the corresponding coefficient matrix is... In the flight control model, the input form of the control surface deflection angle is u(t)=[δ ain δ aout δ sp δ rup δ rlow ] T , where δ ain and δ aout The inputs are the deflection angles of the inner and outer ailerons, δ.sp The deflection angle input for the spoiler is δ. rup and δ rlow These are the deflection angles of the up and down rudders, respectively, where A is the linearized parameter matrix of the pre-augmented flight control model, and B... f For the control gain matrix, C f G is the full-state output matrix, G is the disturbance term matrix, and S is the full-state output matrix. out This is the attitude angle output matrix.

[0051] In another embodiment, the redundant actuation system model of the system is as follows:

[0052] Where δ is the out-of-tolerance threshold of the redundant actuation system; u sys For the system-level input of the actuation system; u A For the A channel input of the actuation system; u B This is the B channel input for the actuation system; The input for a fault-free and normal response in channel A of the redundancy actuation system; For the redundancy actuation system, channel B has a fault-free normal response input; t begin-fault The moment when the response of channel A of the redundancy actuation system begins to reach the switching threshold; t after-fault The moment when the redundancy actuation system's B channel successfully switches and begins to eliminate fault threshold deviations.

[0053] In one further embodiment, the flight control model response performance optimization form is an LQ quadratic form. in For the controller of the flight control model, K = [K x K e To control the gain, and These are the weight matrices for the augmented state vector and input vector of the flight control model, respectively, where Q... x Q is the augmented pre-state vector. e To augment the integral term of the error before the expansion, R x Before augmentation, the input vector R e Let P be the weight matrix of the unaugmented correlation error vector, and let P be the solution matrix of the control gain of the Riccati equation.

[0054] In one further embodiment, the upper bound of the flight control model response is Among them, P c It is a positive definite symmetric matrix, and γ is the perturbation suppression coefficient.

[0055] In another embodiment, the quantification of the impact of the switching threshold on flight control response performance indicators is as follows: e(δ(t)) is the state vector error term caused by the switching threshold.

[0056] In another embodiment, the quantification of the impact of fault tolerance response time on flight control response performance indicators is as follows:

[0057] In another embodiment, let (∫e(τ)dt)Q e The formulas for determining the range of values ​​for the redundancy actuation system fault switching threshold δ and the redundancy actuation system fault tolerance response time Δt under different disturbances are: (∫e(τ)dt)=b. Where, λ 2 ||w|| 2 =w T (τ)G T Gw(τ), where λ is the spectral radius of matrix G.

[0058] In another embodiment, the channel switching criteria for the redundancy actuation system are as follows:

[0059] The criterion for determining the maximum permissible time for channel switching in a redundancy actuation system is that when the external interference w is bounded, w has an upper bound on its norm ||w||. max At this point, the allowable response time reaches its maximum value (Δt). max Within this time, the switching is smooth; when the external interference is a pulse-type interference, w has no upper bound of norm for a short period of time. At this time, the redundancy actuation system faces extreme conditions and the redundancy actuation system performs transient switching; regarding the criteria for judging the maximum switching threshold of the redundancy actuation system, when the value of the flight control model response is determined, the shorter the duration of the error of the actuation system within the critical value, the larger its out-of-tolerance threshold setting is.

[0060] According to a second aspect embodiment, a redundancy actuation system is provided, wherein the redundancy actuation system uses the redundancy actuation system channel switching method of the present invention to switch the redundancy actuation system.

[0061] According to a second aspect embodiment, an aircraft is provided, the aircraft being equipped with the redundancy actuation system described in this invention.

[0062] To gain a better understanding of the channel switching method for a redundancy actuation system provided by the present invention, a detailed description is provided below with reference to specific examples and accompanying drawings.

[0063] like Figure 1 As shown, a channel switching method for a redundancy actuation system includes the following steps:

[0064] Step 1: Establish a flight control model based on the pitch, roll, and yaw functions of the aircraft, which are determined by the elevator, aileron, and rudder respectively.

[0065] The state-space form of the flight control model was linearized at a certain stable operating point, as shown in the following formula:

[0066]

[0067] In the above model, the state variable x = [β pr φ] T Where β is the sideslip angle, p is the roll rate, r is the yaw rate, and φ is the roll angle, the input form of the control surface deflection angle in the flight control model is u = [δ ain δ aout δ sp δ rup δ rlow ] T , where δ ain and δ aout The inputs are the deflection angles of the inner and outer ailerons, δ. sp The deflection angle input for the spoiler is δ. rup and δ rlow These are the inputs for the rudder deflection angle in the up and down directions, respectively.

[0068] Define the flight command as r(t), and the flight control model output response as S. out If y(t), then the response error e(t) = r(t) - S out y(t) can be obtained in its augmented form from the basic flight control model.

[0069]

[0070] Where x aug (t)=[x(t) ∫e(t)dt] T y aug (t)=[y(t) ∫e(t)dt] T w aug (t)=[w(t) r(t)] T The corresponding coefficient matrix is

[0071] Step 2: Determine the optimization form of the flight control model response performance based on the flight control model;

[0072] The controller type of the flight control model is as follows: Where K = [K x K e To control the gain, the flight control model response performance optimization form is defined as an LQ quadratic form. In one specific embodiment, to remove the cumulative effect of the index since the calculation time, a fixed sliding window step size method is used to calculate the quantization value within a fixed time interval. The principle of this sliding window calculation is as follows: Figure 2 As shown.

[0073] Step 3: Determine the upper bound of the flight control model's response;

[0074] The response of the switching transient flight control model is defined as a disturbance, and a disturbance suppression coefficient γ is defined. Solving for the controller gain of the flight control model under disturbance suppression conditions yields the disturbance suppression input. Based on this, the Riccati constraint equations are solved.

[0075]

[0076] Where P c Given a positive definite symmetric matrix, the control gain can be solved in the following form: Based on this form of control gain, the flight control model response can possess bounded response performance, with its index function having an upper bound of .

[0077] Step 4: Use the redundant actuation system as the input to the flight control model, and use the attitude angles controlled by the actuation system as the model output to model the redundant actuation system of the system.

[0078] Assuming that all input components of the flight control model's actuation system are redundant actuation systems, the following definitions are first made to model the redundant actuation system:

[0079] δ: The out-of-tolerance threshold for redundant actuation systems;

[0080] u sys System-level inputs to the actuation system;

[0081] u A :A channel input of the actuation system;

[0082] u B :B channel input of the actuation system;

[0083] The redundant actuation system's A channel is functioning normally and responds to inputs without faults.

[0084] The redundant actuation system's B channel responded normally without any faults.

[0085] t begin-fault The moment when the response of channel A of the redundancy actuation system begins to reach the switching threshold;

[0086] t after-fault The redundancy actuation system B channel switching was successful, and the moment of starting to eliminate fault threshold deviation began.

[0087]

[0088] Since the switching of the actuation system is completed transiently, the switching time is ignored, and only the fault tolerance response time Δt = t is considered. after-fault -tbegin-fault During this period, the flight control model's actuation system had no input to this channel, only interference input.

[0089] Step 5: Based on the input of the flight control model and the fault switching threshold δ of the redundant actuation system, determine the quantitative value of the impact of the switching threshold on the flight control response performance index.

[0090] because For the flight control model input, the flight control response error caused by the threshold of the actuation system input can be defined as...

[0091] Because the performance index is in the form of

[0092]

[0093] Based on the above form, considering the fixed threshold error, it can be deduced that the quantified value of the impact of the threshold deviation on the flight control response performance index is:

[0094]

[0095] Step 6: Based on the input of the flight control model and the fault tolerance response time Δt of the redundancy actuation system, set the quantitative increment of the response performance index caused by the fault switching threshold δ of the redundancy actuation system to zero, and determine the quantitative value of the impact of the fault tolerance response time on the flight control response performance index.

[0096] The following model is used to model the response error index caused by the pure switching time. During switching, the redundancy actuation system has a brief state of no input, that is, u(t) = 0 during the time Δt. The only input is the disturbance input Gw(t). The index quantity is calculated according to the performance index form.

[0097]

[0098] According to the principle of small perturbations

[0099]

[0100] Therefore, we take its upper bound form.

[0101]

[0102] Step 7: Based on the upper bound of the flight control model response obtained under different external disturbances, the quantitative value of the impact of the switching threshold on the flight control response performance index, and the quantitative value of the impact of the fault tolerance response time on the flight control response performance index, determine the range of values ​​for the fault switching threshold δ of the redundancy actuation system and the fault tolerance response time Δt of the redundancy actuation system under different disturbances.

[0103] The sum of the threshold response error and the response error caused by the switching time in the flight control model is calculated as follows:

[0104]

[0105] The index function form of flight control response is affected by the duration of error and the amount of external interference input. Based on the redundancy actuation system channel switching criteria, the redundancy actuation system channel switching method is determined for different error durations and external interference inputs.

[0106] Based on the quantitative requirements for flight quality, an upper bound is set for the increment of the indicator function variables.

[0107]

[0108] make (∫e(τ)dt)Q e (∫e(τ)dt)=b, then

[0109]

[0110] As can be seen from the above form, given that the switching threshold δ(t) and the switching tolerance time Δt of the redundancy actuation system are determined, the uncertainty variable affecting the index function depends on the external disturbance input w(τ). T (τ)G T Gw(τ) can be written in maximal norm form as λ. 2 ||w|| 2 Where λ is the spectral radius of matrix G, the final form of the index function is:

[0111] ΔJ max =J δ +J Δt

[0112] = a(δ(t))t+bΔt+(1+γ 2 )λ 2 ||w|| 2 Δt=a(δ(t))t+(b+(1+γ 2 )λ 2 ||w|| 2 )Δt

[0113] The formulas for determining the range of values ​​for the redundancy actuation system fault switching threshold δ and the redundancy actuation system fault tolerance response time Δt under different disturbances are as follows:

[0114] Where, λ 2 ||w|| 2 =w T (τ)G T Gw(τ), where λ is the spectral radius of matrix G.

[0115] As can be seen from the above, under the premise of determining the switching threshold and switching time of the redundancy actuation system, the index function of the flight control response is mainly affected by the duration of the error and the amount of external interference input. If the external interference input is a pulse-type input and the allowable switching time of the actuation system is set too long, the index function will instantly exceed the maximum constraint.

[0116] Criteria for determining the maximum allowable time for channel switching in a redundancy actuation system:

[0117] By ΔJ max =a(δ(t))t+(b+(1+γ) 2 )λ 2 ||w|| 2 )Δt can be obtained

[0118] (1) When the external disturbance w is a bounded disturbance, then w has an upper bound on its norm ||w||. max ,at this time That is, the threshold out-of-tolerance integral value of the redundancy actuation system A channel must be minimized, i.e., the out-of-tolerance time t must be minimized. min At this point, the acceptable response time can reach its maximum value (Δt). max To ensure transient characteristics during switching, a smooth switching process can be implemented within this timeframe.

[0119] (2) When the external interference is pulse-type interference, w has no upper bound on the norm for a short period of time, that is, ||w||→∞. When the redundancy actuation system faces extreme operating conditions, the switchover needs to be completed rapidly within a very short time. At this time, the maximum allowable switchover time of the redundancy actuation system is in the millisecond range. Sacrificing flight quality and prioritizing flight safety, the redundancy actuation system performs transient switchover.

[0120] The basis for setting the maximum switching threshold for redundant actuation systems:

[0121] By ΔJ max =a(δ(t))t+(b+(1+γ) 2 )λ 2 ||w|| 2 )Δt can be obtained Based on the above analysis, a channel switching criterion for the redundancy actuation system is formulated. a(δ(t)) is inversely proportional to the threshold deviation time. Therefore, given a fixed error index function value, the shorter the duration of error within the critical value, the larger the deviation threshold can be set. The specific relationship expression is as follows: For, in this formula, ΔJ max For a constant value, t min a(δ(t)) represents the shortest duration of the actuation system within the response threshold error. maxThis indicates the maximum configurable switching threshold integral.

[0122] Algorithm simulation verification

[0123] The selected flight control model parameter matrix, after linearization, is shown below:

[0124]

[0125] The solved control gain matrix is

[0126]

[0127] The application architecture of the switching algorithm in the case of channel failure or performance degradation of the redundancy actuation system according to the present invention is as follows: Figure 3 As shown, the simulation scenarios in this invention include "no-handover algorithm", "bounded interference handover", and "pulse interference handover". Specific simulation results are attached. Figure 4 As shown in the simulation results, in the case of a main channel failure, if there is no channel switching algorithm to distinguish between the two, the flight control attitude of the redundant actuation system will diverge and lose control. With the algorithm designed in this invention, in the presence of bounded disturbances, the redundant actuation system can complete the smooth channel switching within the optimized specified time, and the flight control attitude can continue to remain stable. In the case of severe pulse disturbances, the redundant actuation system can complete the transient switching according to the algorithm described in this invention. The flight control attitude may jitter, but the overall stability can be maintained, sacrificing flight quality to ensure flight safety.

[0128] In summary, the channel switching method for a redundancy actuation system provided by this invention has at least the following advantages compared to the prior art:

[0129] This invention optimizes the channel switching criteria of the redundancy actuation system by determining the range of values ​​for the fault switching threshold δ and the fault tolerance response time Δt of the redundancy actuation system. This avoids invalid switching and waste of fault tolerance resources caused by overly stringent switching conditions, while ensuring effective switching of the redundancy actuation system when the current channel is severely faulty, as well as the controllable transient characteristics and good flight quality of the aircraft.

[0130] The above are merely preferred embodiments of the present invention and are not intended to limit the present invention. Various modifications and variations can be made to the present invention by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

Claims

1. A channel switching method for a redundancy actuation system, characterized in that, Includes the following steps: Based on the pitch, roll, and yaw functions of the aircraft, which are determined by the elevator, aileron, and rudder respectively, a flight control state space model, i.e., a flight control model, is established. The optimization form of the response performance index is determined based on the flight control model; the optimization form of the flight control model response performance is an LQ quadratic form. ,in The controller for the flight control model. State variables ,in Sideslip angle, For the roll rate, The yaw rate, For roll angle, , For response error, For flight control commands, Due to external interference, Output attitude angles for the flight control model. , For coefficients, To control the gain, , and These are the weight matrices for the augmented state vector and input vector of the flight control model, respectively. For the augmented pre-state vector, To augment the integral term of the previous error, Before augmentation, the input vector The weight matrix for the pre-amplified correlation error vector, The solution matrix for the control gain of the Riccati equation. , For control gain matrix; Determine the quantitative upper bound of the flight control model response performance index; the upper bound of the flight control model response is... ,in, , It is a positive definite symmetric matrix. This is the disturbance suppression coefficient; The redundant actuation system is used as the input to the flight control model, and the attitude angle controlled by the actuation system is used as the model output. The redundant actuation system components of the system are modeled. Based on the input of the flight control model and the fault switching threshold of the redundant actuation system The quantitative value of the impact of the switching threshold on the flight control response performance index was determined under the condition that a rapid switch is required for sudden failures. Based on the input of the flight control model and the fault tolerance response time of the redundant actuation system For slowly degrading performance failures in redundant actuation systems, since these failures do not cause the system to reach the switching threshold in a short period of time... Therefore, the fault switching threshold of the redundancy actuation system will be adjusted. The resulting quantitative increment of the response performance index is set to zero, thereby determining the quantitative value of the impact of the cumulative effect of fault tolerance response time on the flight control response performance index; the quantitative value of the impact of fault tolerance response time on the flight control response performance index is as follows: ; in, Let be the interference term matrix, and let , The threshold for determining the redundancy actuation system fault switching and redundancy actuation system fault tolerance response time The formula for the range of values ​​under different disturbances is: ,in, = , For matrix spectral radius; Based on the upper bound of the flight control model response obtained under different external disturbances, the quantitative value of the impact of the switching threshold on the flight control response performance index, and the quantitative value of the impact of the fault tolerance response time on the flight control response performance index, the fault switching threshold of the redundancy actuation system is determined. and redundancy actuation system fault tolerance response time The range of values ​​under different disturbances is used as the upper bound of the flight control model response as the index optimization term to form the channel switching criterion; The index function form of flight control response is affected by the duration of error and the amount of external interference input. Based on the redundancy actuation system channel switching criteria, the redundancy actuation system channel switching method is determined for different error durations and external interference inputs.

2. The channel switching method for a redundancy actuation system according to claim 1, characterized in that, The state-space model for aircraft flight control is as follows: ,in, The corresponding coefficient matrix is , , The input form of the control surface deflection angle in the flight control model is as follows: ,in and The inputs are the deflection angles of the inner and outer ailerons, respectively. Input the deflection angle of the spoiler. and These are the inputs for the yaw angles of the up and down rudders, respectively. To augment the linearized parameter matrix of the pre-flight control model, For the full-state output matrix, For the interference term matrix, This is the attitude angle output matrix.

3. The channel switching method for a redundancy actuation system according to claim 2, characterized in that, The input form of the redundant actuation system model is: ,in, The out-of-tolerance threshold for redundant actuation systems; For the system-level input of the actuation system; This is the A-channel input for the actuation system; This is the B channel input for the actuation system; The input for a fault-free and normal response in channel A of the redundancy actuation system; The input for a fault-free and normal response in channel B of the redundancy actuation system; The moment when the response of channel A of the redundancy actuation system begins to reach the switching threshold; The moment when the redundancy actuation system's B channel successfully switches and begins to eliminate fault threshold deviations.

4. The channel switching method for a redundancy actuation system according to claim 3, characterized in that, The channel switching criteria for the redundancy actuation system are as follows: The criterion for determining the maximum allowable time for channel switching in the redundancy actuation system is based on external interference. For bounded interference, then Has an upper bound on the norm At this point, the allowable response time reaches its maximum value. Within this time frame, the redundancy actuation system can switch smoothly; when the external disturbance is a pulse-type disturbance, then... When there is no upper bound on the norm for a short period of time, the redundant actuation system faces extreme conditions and performs transient switching. Regarding the criteria for determining the maximum switching threshold of the redundant actuation system, under the condition that the preset value of the flight control model response is determined, the shorter the duration of the error of the actuation system within the critical value, the larger its out-of-tolerance threshold setting should be.

5. A redundant actuation system, characterized in that, The redundant actuation system is switched using the redundant actuation system channel switching method according to any one of claims 1-4.

6. An aircraft, characterized in that, The aircraft is equipped with the redundancy actuation system as described in claim 5.

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