Safety protection design method for adaptive augmentation controller of carrier rocket

Abstract

The invention discloses a safety protection design method for a self-adaptive augmentation controller of a carrier rocket, and the method comprises the steps: simplifying an error term of the self-adaptive augmentation controller, and obtaining a single-input-output AAC controller; amplitude limiting design is carried out on parameter angular rate deviation delta omega, an error term er, a carrier rocket attitude angle # imgabs0 # and a damping term ys signal of an error term loop and a damping term loop of the single-input-output AAC controller; carrying out amplitude limiting on an output channel of the output loop, and carrying out amplitude limiting on the output change rate of the AAC controller; and setting a trigger access mechanism for the output change rate of the single-input-output AAC controller. According to the safety protection design method for the self-adaptive augmentation controller of the carrier rocket, the safety protection design problem of the self-adaptive augmentation controller adopted by the carrier rocket is solved, and the engineering application effects of being beneficial, harmless, easy and convenient to design, flexible and reliable are achieved.

Description

Technical Field

[0001] The invention relates to a safety protection design method for a carrier rocket adaptive augmentation controller, belonging to the technical field of spacecraft control. Background Art

[0002] During the flight of a launch vehicle, it is subject to complex superposition interference from different frequency bands and different intensities. The overload that a launch vehicle can withstand is relatively low, and its sensitivity to interference is also higher than that of other aircraft. When the rocket body is subject to external interference, the control bandwidth needs to be increased to cope with it. However, when the control signal changes too quickly and the bandwidth is too high, there is a problem of weak adaptability. For this reason, in the process of applying AAC control technology to launch vehicles, it is necessary to design the safety of the AAC controller according to the characteristics of the controlled object, including the input and output limits of each loop, the limits of the AAC controller output value and output change rate, and the trigger switch mechanism of the AAC controller.

[0003] At present, adaptive augmented controllers have not been widely used in the field of launch vehicles, and there are still no clear industry standards and successful cases for reference for related safety protection design methods. In public literature, it is generally emphasized to limit the output signal of the adaptive augmented controller, and there are no other safety protection measures. This limiting design only provides simple protection for the output layer of the adaptive augmentation to ensure that it is bounded. However, there are no effective protection measures for the frequency characteristics of the output signal, and it cannot meet the flight application requirements of the launch vehicle. At the same time, this method cannot protect the output of the entire adaptive augmented controller through local isolation, limiting and other measures when a branch of the adaptive augmented controller is abnormally calculated, nor can it realize the autonomous switching function of the adaptive augmented controller when necessary. In summary, the existing methods still have room for improvement. Summary of the invention

[0004] The technical problem solved by the present invention is: to overcome the deficiencies of the prior art, to provide a safety protection design method for an adaptive augmented controller for a launch vehicle, to adjust the structure of the AAC controller, and to perform protection design on each circuit, to solve the safety protection design problem of an adaptive augmented controller for a launch vehicle, and to achieve a beneficial, harmless, simple in design, flexible and reliable engineering application effect.

[0005] The technical solution of the present invention is: a safety protection design method for a launch vehicle adaptive augmented controller, wherein:

[0006] Adjusting the error term of the adaptive augmentation controller to obtain a single-input-output adaptive augmentation controller, wherein the adaptive augmentation controller is denoted as an AAC controller;

[0007] The error term loop and damping term loop parameters of the single-input-output AAC controller are the angular velocity deviation Δω, the error term e r , launch vehicle attitude angle and the damping term y s The signal is limited.

[0008] Limit the output channel of the output loop and limit the output change rate of the AAC controller;

[0009] A trigger access mechanism is set for the output change rate of the single-input-output AAC controller.

[0010] Preferably, the single-input-output AAC controller is specifically:

[0011] The output loop signal expression of the AAC controller is:

[0012]

[0013] k t =k a +k0

[0014] Among them, k t is the adaptive final output coefficient, k a is the integral part of the output coefficient, and k0 is the constant part of the output coefficient; k a The derivative of k tmax is the upper limit of the output coefficient, e r is the error term, which indicates the deviation value of the reference model; s is the damping term, which represents the spectrum damper filter value; a is the error term weight, c is the damping term weight, and β is the regression term weight;

[0015] The formula for the damping term is:

[0016] y s =D(G(y3) 2 )

[0017]

[0018] The formula defining the error term is:

[0019]

[0020] Among them, a0 and a1 are constant coefficients. Δω represents the attitude angle and angular rate deviation of the launch vehicle, respectively. G(·), D(·), and N(·) represent the filter functions of the high-pass filter, low-pass filter, and correction network, respectively.

[0021] Preferably, the error term loop and the damping term loop of the AAC controller are limited, specifically:

[0022] Based on the control accuracy requirements of the flight mission, mathematical simulation is performed under normal working conditions to obtain the angular rate deviation Δω and the error term e r , launch vehicle attitude angle and the damping term y s The signal envelope range; combined with the elastic characteristics of the rocket and the sampling frequency of the onboard computer, and e r The limit value is greater than the acceptable attitude angle deviation envelope during flight. Let y s The signal limit value is equal to the envelope range of the elastic deviation of the rocket body;

[0023] For Δω, the Δω signal is written as the rigid body angular velocity Δω required by the system g Elastic noise Δω in different frequency bands tx (f) Superposition form Δω=Δω g +Δω tx (f) The limit value should be designed to cover the maximum variation range of the above signal, so as to ensure that the subsequent filter input will not be aliased or damaged due to limit.

[0024] Preferably, the output loop of the AAC controller is limited, specifically:

[0025] By using the worst margin principle, without the AAC controller, the static gain factor a0 of the system is adjusted until the rocket control system reaches the upper and lower boundaries of critical stability respectively; under the requirement of frequency domain stability in this worst state, the upper limit amplitude k of the output channel is determined tmax and the lower limit value k tmin .

[0026] Preferably, the output change rate of the AAC controller is limited, specifically:

[0027] Define the interference signal d(ω) as:

[0028] d(ω)=A w (ω)·sin(ω·t)

[0029] Among them, A w is the interference amplitude, ω is the frequency, and t is the time;

[0030] Consider the rigid body cutoff frequency ω of the arrow body g and the first-order elastic frequency ω t The interference magnitude of the two important frequency bands is obtained through frequency domain analysis and mathematical simulation. w (ω g ) and Aw (ω t ), select the minimum value of the two as the reference envelope, and obtain the maximum interference acceleration amplitude A that the rocket body can accept in different frequency bands wf :

[0031] A wf =min(A w (ω g ),A w (ω t ))

[0032] For the AAC controller output, it is necessary to consider that its rate of change amplitude does not exceed the above interference level. Considering that the first-order elastic frequency of the rocket body is greater than the rigid body cutoff frequency, the minimum envelope combination is taken to obtain the AAC controller output change rate Limiting:

[0033]

[0034] Among them, κ is a coefficient less than 1 and is selected according to actual task requirements.

[0035] Preferably, when setting a trigger access mechanism for the output change rate of the AAC controller, the trigger judgment is divided into two layers:

[0036] The first layer is for time judgment. In the rocket takeoff phase, large attitude maneuver phase, and shutdown separation phase, the AAC controller switch judgment operation is not performed to avoid the AAC controller step jump causing additional interference to the system;

[0037] The second level judgment adopts the change rate single-step trigger method, and the AAC controller output change rate is preset. as well as Rate of change The trigger threshold Only when the calculation results of the AAC controller meet the following conditions:

[0038]

[0039] Will be output normally, otherwise, the current moment Set to zero;

[0040] in, They are and The absolute value of , && represents logical AND.

[0041] Preferably, for the single-input-output AAC controller framework, there is only one input and one output, and the input is the error term e r .

[0042] In a second aspect, a terminal device is provided, including:

[0043] a memory for storing instructions executed by at least one processor;

[0044] The processor is used to execute instructions stored in the memory to implement the safety protection design method of the launch vehicle adaptive augmented controller as described above.

[0045] According to a third aspect, a computer-readable storage medium is provided for storing computer instructions. When the computer instructions are executed on a computer, the computer executes the launch vehicle adaptive augmented controller safety protection design method as described above.

[0046] Compared with the prior art, the present invention has the following advantages:

[0047] (1) The AAC controller structure of the present invention is more concise, which is of great help to subsequent parameter design and stability evaluation;

[0048] (2) After the safety design of each path of the present invention is carried out respectively, it is ensured that the path calculation is smooth and correct, and there will be no problems such as calculation singularity and memory overflow, and it will not cause the posture of the controlled object to shake violently or cause additional interference to the controlled object;

[0049] (3) After the change rate trigger mechanism is added to the present invention, it is ensured that the AAC controller does not intervene too much in the control when the controlled object is in stable flight, but can respond quickly when necessary, quickly achieving the effect of improving the adaptability, playing a beneficial role without harming it. BRIEF DESCRIPTION OF THE DRAWINGS

[0050] Figure 1 It is a block diagram of the system composition of the present invention;

[0051] Figure 2 The dimensions of the moon sand table screen and the moon simulation diagram of the present invention;

[0052] Figure 3 This is a diagram of the three-dimensional translational motion device of the present invention. DETAILED DESCRIPTION

[0055] Aiming at the safety and reliability requirements of the existing adaptive augmentation controller applied to launch vehicles, the present invention provides a safety protection design method for an adaptive augmentation control (AAC) controller for launch vehicles, adjusts the structure of the AAC controller, and performs protection design for each circuit.

[0056] To achieve the above-mentioned purpose, the technical solution adopted by the safety protection design method of a launch vehicle adaptive augmentation controller of the present invention is as follows:

[0057] According to the characteristics of the launch vehicle's flight mission, in order to ensure that the AAC controller will not have abnormal output or cause additional interference to the rocket body during flight, the safety protection design of the AAC controller specifically includes changing the AAC controller to a single input-output structure, adding limits to the input and output circuits, increasing the limits on the AAC controller's output value and output change rate, and introducing an AAC controller trigger switch mechanism; specifically:

[0058] 1) First, adjust and improve the AAC controller path. Modify the AAC algorithm access position and add a correction network to the error term loop to simplify the control structure and construct a single-input-single-output structure;

[0059] 2) Based on the single-input-single-output structure, the three sub-modules of the AAC controller are integrated, and the limiting and protection designs are carried out on the integrated input paths respectively;

[0060] 3) Based on the interference sensitivity analysis of the controlled object and the frequency domain margin index requirements under the worst working condition, the maximum acceptable interference acceleration value is obtained by the sine derivative method, and the output limit value and output change rate limit value of the AAC controller are set;

[0061] 4) Finally, in view of actual flight requirements, in order to avoid unnecessary high-frequency jitter of the AAC controller output, a trigger access mechanism based on the AAC controller output change rate is proposed for the output path.

[0062] In conjunction with the accompanying drawings, the present invention proposes a launch vehicle adaptive augmentation controller (AdaptiveAugmentation Control, AAC) safety protection design method, the specific implementation steps are as follows:

[0063] 1) According to the characteristics of the launch vehicle's flight mission, in order to ensure that the AAC controller does not have abnormal output or cause additional interference to the rocket body during flight, a safety protection design is carried out for the AAC controller. The specific design parameters include each loop input, output limit, AAC controller output value and output change rate limit, and AAC controller trigger switch mechanism;

[0064] 2), first analyze and adjust the mathematical formula of the adaptive augmentation control (AAC) controller. The output loop signal expression of the AAC controller is:

[0065]

[0066] kt =k a +k0 (2)

[0067] Among them, k t is the adaptive final output coefficient, k a is the integral part of the output coefficient, and k0 is the constant part of the output coefficient. k a The derivative of k tmax is the upper limit of the output coefficient; e r is the error term, which indicates the deviation value of the reference model; s is the damping term, which represents the filter value of the spectrum damper. a is the error term weight, c is the damping term weight, and β is the regression term weight. In the expression of the output loop, e r and s are the low-frequency and high-frequency interference signal values, respectively, which are calculated by the error term loop and the damping term loop. The error term formula is:

[0068]

[0069] The damping term formula is:

[0070] y s =D(G(y3) 2 ) (4)

[0071]

[0072] Among them, a0 and a1 are constant coefficients. Δω is the attitude angle and angular rate deviation of the launch vehicle, respectively. G(·), D(·), and N(·) represent the filter functions of the high-pass filter, low-pass filter, and correction network, respectively. By observing the above formula, it can be seen that the inputs of the error term loop and the damping term loop are different, and the correction network environment is increased. In order to simplify the system, the formula of the error term loop is defined as:

[0073]

[0074] The obtained system block diagram is shown in Figure 1 After the above improvements, a single-input-output AAC controller framework can be obtained, thereby simplifying the subsequent system design.

[0075] 3) Based on the single-input-output AAC controller framework, we can know that the AAC controller has only one input Therefore, the error term loop, damping term loop and output loop of the AAC controller can be integrated for parameter design.

[0076] It can be seen from the formula that the input of the AAC control system is e r, which directly acts on the error loop. Considering that in actual flight, the angular rate signal generally has more burrs and high-frequency jitter interference. When the system is in the limiting state, this interference may occupy the channel space in the low frequency band. Therefore, for Δω and e r On the contrary, in the damping term loop, considering that high-frequency interference should be identified first, it is necessary to and s The specific method is as follows: Based on the control accuracy requirements of the flight mission, mathematical simulation is performed under normal working conditions to obtain Δω, e r , and s The signal envelope range. At the same time, combined with the elastic characteristics of the rocket and the sampling frequency of the onboard computer, and e r The limit value is greater than the acceptable attitude angle deviation envelope during flight, y s The signal limit value is equal to the elastic deviation envelope range of the rocket body. For Δω, it is necessary to consider the influence of elasticity on the sensor entering the control closed loop. The Δω signal can be written as the rigid body angular velocity Δω required by the system. g Elastic noise Δω in different frequency bands tx (f) Superposition form Δω=Δω g +Δω tx (f) The limit value should be designed to cover the maximum variation range of the above signal, so as to ensure that the subsequent filter input will not be aliased or damaged due to limit.

[0077] Finally, in the output loop, by using the worst margin principle, without the AAC controller, the system static gain factor a0 is adjusted until the rocket control system reaches the upper and lower boundaries of critical stability. Under the requirement of frequency domain stability in this worst state, the upper limit amplitude k of the output channel is determined. tmax and the lower limit value k tmin The schematic diagram of the upper and lower limits of the AAC controller obtained by the translation margin diagram is shown in Figure 2 .

[0078] 4) Based on the single-input-output AAC controller framework, the system has only one output k t In the traditional method, only the value is limited. In the present invention, in view of the sensitivity of the launch vehicle to the angular velocity of interference with different frequencies, an innovative method is proposed to t Based on the limiting, the AAC output changes rate Based on the frequency domain margin analysis and time domain simulation analysis, the anti-interference ability of the rocket body in different frequency bands is pre-evaluated, and the maximum interference acceleration amplitude A that the rocket body can accept in different frequency bands is given. wf .

[0079] The mathematical expression of the interference signal d(ω) is:

[0080] d(ω)=A w (ω)·sin(ω·t) (7)

[0081] Among them, A w is the interference amplitude, ω is the frequency, and t is the time. It can be seen that the interference signal d(ω) is a function of frequency. For launch vehicles, the rigid body cutoff frequency ω of the rocket body is generally concerned. g and the first-order elastic frequency ω t The interference magnitude of the two important frequency bands. Through frequency domain analysis and mathematical simulation, the interference amplitude A of the above two frequency bands can be obtained. w (ω g ) and A w (ω t ). Select the minimum value of the two as the reference envelope, recorded as:

[0082] A wf =min(A w (ω g ),A w (ω t )) (8)

[0083] For the AAC controller output, it is necessary to consider that its rate of change amplitude cannot exceed the above interference level. Considering that the first-order elastic frequency of the rocket body is greater than the rigid body cutoff frequency, the minimum envelope combination is taken to obtain the AAC controller output change rate Limiting:

[0084]

[0085] Among them, κ is a coefficient less than 1 and is selected according to actual task requirements.

[0086] 5), formula (9) has designed a limiter for the output path of the single-input-output AAC controller framework to ensure that the output signal will not be too large and contain too many high-frequency characteristics. This method can suppress the interference of high-frequency disturbances with large amplitudes on low-frequency angular rate signals. However, in order to optimize the interference to the system when the amplitude of the high-frequency interference signal is small, it is necessary to propose a trigger access mechanism based on the output change rate of the AAC controller. The trigger judgment is divided into two layers. The first layer is for time judgment. During the rocket takeoff phase, large attitude maneuver phase, shutdown and separation phase, etc., the AAC controller switch judgment operation is not performed to avoid the AAC controller step jump causing additional interference to the system. The second layer of judgment adopts the change rate single-step trigger method to pre-set the AAC controller output change rate. as well as Rate of change Trigger threshold In actual flight, the AAC controller can only be used when the calculation results meet the following conditions:

[0087]

[0088] in, They are and The absolute value of && represents the logical AND, that is, only when both of the above conditions are met, Will be output normally, otherwise, the current moment Set to zero. See the trigger determination flow chart Figure 3 .

[0089] In a second aspect, a terminal device is provided, including:

[0090] a memory for storing instructions executed by at least one processor;

[0091] The processor is used to execute instructions stored in the memory to implement the safety protection design method of the launch vehicle adaptive augmented controller as described above.

[0092] According to a third aspect, a computer-readable storage medium is provided for storing computer instructions. When the computer instructions are executed on a computer, the computer executes the launch vehicle adaptive augmented controller safety protection design method as described above.

[0093] The contents not described in detail in the specification of the present invention belong to the prior art known to the professional and technical personnel in this field.

Claims

1. A safety protection design method for a launch vehicle adaptive augmented controller, characterized in that include: Adjusting the error term of the adaptive augmentation controller to obtain a single-input-output adaptive augmentation controller, wherein the adaptive augmentation controller is denoted as an AAC controller; The error term loop and damping term loop parameters of the single-input-output AAC controller are the angular velocity deviation Δω, the error term e r , launch vehicle attitude angle and the damping term y s The signal is limited. Limit the output channel of the output loop and limit the output change rate of the AAC controller; A trigger access mechanism is set for the output change rate of the single-input-output AAC controller.

2. A launch vehicle adaptive augmentation controller safety protection design method according to claim 1, characterized in that: Single input and output AAC controller, specifically: The output loop signal expression of the AAC controller is: k t =k a +k0 Among them, k t is the adaptive final output coefficient, k a is the integral part of the output coefficient, and k0 is the constant part of the output coefficient; k a The derivative of k tmax is the upper limit of the output coefficient, e r is the error term, which indicates the deviation value of the reference model; s is the damping term, which represents the spectrum damper filter value; a is the error term weight, c is the damping term weight, and β is the regression term weight; The formula for the damping term is: y s =D(G(y3) 2 ) The formula defining the error term is: Among them, a0 and a1 are constant coefficients. Δω represents the attitude angle and angular rate deviation of the launch vehicle, respectively. G(·), D(·), and N(·) represent the filter functions of the high-pass filter, low-pass filter, and correction network, respectively.

3. A launch vehicle adaptive augmentation controller safety protection design method according to claim 1, characterized in that: The error term loop and damping term loop of the AAC controller are limited by: Based on the control accuracy requirements of the flight mission, mathematical simulation is performed under normal working conditions to obtain the angular rate deviation Δω and the error term e r , launch vehicle attitude angle and the damping term y s The signal envelope range; combined with the elastic characteristics of the rocket and the sampling frequency of the onboard computer, and e r The limit value is greater than the acceptable attitude angle deviation envelope during flight. Let y s The signal limit value is equal to the envelope range of the elastic deviation of the rocket body; For Δω, the Δω signal is written as the rigid body angular velocity Δω required by the system g Elastic noise Δω in different frequency bands tx (f) Superposition form Δω=Δω g +Δω tx (f) The limit value should be designed to cover the maximum variation range of the above signal, so as to ensure that the subsequent filter input will not be aliased or damaged due to limit.

4. A launch vehicle adaptive augmentation controller safety protection design method according to claim 1, characterized in that: The output circuit of the AAC controller is limited by: By using the worst margin principle, without the AAC controller, the static amplification factor a0 of the system is adjusted until the rocket control system reaches the upper and lower boundaries of critical stability respectively; under the requirement of frequency domain stability in this worst state, the upper limit amplitude k of the output channel is determined tmax and the lower limit value k tmin .

5. The safety protection design method for a launch vehicle adaptive augmentation controller according to claim 1 is characterized in that: The output change rate of the AAC controller is limited as follows: Define the interference signal d(ω) as: d(ω)=A w (ω)·sin(ω·t) Among them, A w is the interference amplitude, ω is the frequency, and t is the time; Consider the rigid body cutoff frequency ω of the arrow body g and the first-order elastic frequency ω t The interference magnitude of the two important frequency bands is obtained through frequency domain analysis and mathematical simulation. w (ω g ) and A w (ω t ), select the minimum value of the two as the reference envelope, and obtain the maximum interference acceleration amplitude A that the rocket body can accept in different frequency bands wf : A wf =min(A w (oh g ),A w (oh t )) For the AAC controller output, it is necessary to consider that its rate of change amplitude does not exceed the above interference level. Considering that the first-order elastic frequency of the rocket body is greater than the rigid body cutoff frequency, the minimum envelope combination is taken to obtain the AAC controller output change rate Limiting: Among them, κ is a coefficient less than 1 and is selected according to actual task requirements.

6. A launch vehicle adaptive augmentation controller safety protection design method according to claim 1, characterized in that: When setting the trigger access mechanism for the output change rate of the AAC controller, the trigger judgment is divided into two layers: The first layer is for time judgment. In the rocket takeoff phase, large attitude maneuver phase, and shutdown separation phase, the AAC controller switch judgment operation is not performed to avoid the AAC controller step jump causing additional interference to the system; The second level judgment adopts the change rate single-step trigger method, and the AAC controller output change rate is preset. as well as Rate of change The trigger threshold Only when the calculation results of the AAC controller meet the following conditions: Will be output normally, otherwise, the current moment Set to zero; in, They are and The absolute value of , && represents logical AND.

7. A launch vehicle adaptive augmentation controller safety protection design method according to claim 1, characterized in that: For the single-input-output AAC controller framework, there is only one input and one output, and the input is the error term e r .

8. A terminal device, characterized in that: include: a memory for storing instructions executed by at least one processor; A processor, configured to execute instructions stored in a memory to implement a method according to any one of claims 1 to 7.

9. A computer-readable storage medium, characterized in that: The computer-readable storage medium stores computer instructions, and when the computer instructions are executed on a computer, the computer is enabled to execute the method according to any one of claims 1 to 7.

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