Direct force adjustable interceptor time optimal attitude control method and system

Abstract

This invention proposes a time-optimal attitude control method and system for a direct force adjustable interceptor, comprising: Step 1, obtaining the interceptor's attitude angular velocity ω, attitude angle θ, and attitude angle command θ. c Step 2: Use the attitude angle command θ c The attitude angle deviation Δθ is calculated using the PD control law to obtain the gain coefficient K for stabilizing the interceptor's attitude. ang Damping coefficient K sf Step 3: Based on the attitude angular velocity ω, the attitude angular deviation Δθ, and the gain coefficient K... ang Damping coefficient K sf Step four: Calculate the engine valve opening command u of the interceptor; Execute the engine valve actuation according to the opening command u to achieve continuously adjustable attitude control thrust and achieve precise attitude tracking control. The interceptor attitude control method of this invention has a fast dynamic response, avoids oscillation and overshoot, and better meets the high dynamic and high precision requirements of the control system.

Description

Technical Field

[0001] This invention relates to the field of aircraft flight control, and in particular to a method and system for optimal control of missile variable structure attitude. Background Technology

[0002] The direct-collision kinetic energy kill interceptor employs advanced automatic homing technology to achieve high-precision autonomous detection, guidance, control, and direct collision kinetic energy destruction of the target. It is a high-precision, highly maneuverable, highly intelligent, and highly photoelectric information-intensive information weapon, representing the development direction and mainstream of anti-missile kill methods. Compared to on / off valve actuators, thrust-adjustable valve actuators offer advantages such as higher control precision and less jitter.

[0003] Traditional PID control, while simple in structure, cannot simultaneously meet the requirements of speed and overshoot; while bang-bang control is the optimal time control, chatter occurs near the switching line, affecting control accuracy. Summary of the Invention

[0004] This invention addresses the challenge of traditional control methods in balancing system dynamics and accuracy under both large and small commands. It provides a time-optimal attitude control method and system for a direct force adjustable interceptor, achieving rapid control response and avoiding oscillations and overshoot.

[0005] This invention proposes a time-optimal attitude control method for a direct force adjustable interceptor, comprising: Step 1, obtaining the interceptor's attitude angular velocity ω, attitude angle θ, and attitude angle command θ. c Step 2: According to the attitude angle command θ c And calculate the attitude angle deviation Δθ based on the attitude angle θ, and then calculate the attitude angle command θ. c The attitude angle deviation Δθ is calculated using the PD control law to obtain the gain coefficient K for stabilizing the interceptor's attitude. ang Damping coefficient K sf Step 3: Based on the attitude angular velocity ω, the attitude angular deviation Δθ, and the gain coefficient K... ang Damping coefficient K sf Calculate the engine valve opening command u of the interceptor; Step 4: Execute the engine valve actuation according to the opening command u.

[0006] Furthermore, in step two, the step of using the attitude angle command θ... c The attitude angle deviation Δθ is calculated based on the PD control law, and the gain coefficient K used for stabilizing the interceptor's attitude is used for control. ang Damping coefficient K sf Specifically, it includes:

[0007]

[0008]

[0009] Where, attitude angle deviation Δθ=θ c -θ, k1 is the gain coefficient that is constant under linear error e1, ζ is the closed-loop damping coefficient of the control system, β is the proportional factor, e1=1 / k1, e2=θ c / β is the threshold for switching control parameters based on error, and a3 is the angular acceleration generated by a unit opening of the engine valve.

[0010] Furthermore, the value of the gain coefficient k1 is the same as... The deviation is a value within the specified range, where ω n The natural frequency of the control system is used; the closed-loop damping coefficient ζ of the control system is between 1.0 and 2.0; the proportional factor β is greater than |Δθ / e1.

[0011] Furthermore, in step three, the engine valve opening command u = sat(x), where sat(x) is a saturation function.

[0012]

[0013] Where x is an intermediate variable, x = K ang ×Δθ-K sf ×ω.

[0014] This invention also proposes a time-optimal attitude control system for a direct force adjustable interceptor, comprising: an attitude and command acquisition module, a control parameter determination module, an engine valve command determination module, and an engine valve control module; wherein, the attitude and command acquisition module acquires the interceptor's attitude angular velocity ω, attitude angle θ, and attitude angle command θ. c The control parameter determination module determines the parameters based on the attitude angle command θ. c And calculate the attitude angle deviation Δθ based on the attitude angle θ, and then calculate the attitude angle command θ. c The attitude angle deviation Δθ is calculated using the PD control law to obtain the gain coefficient K for stabilizing the interceptor's attitude. ang Damping coefficient K sf The engine valve command determination module determines the attitude angular velocity ω, the attitude angle deviation Δθ, and the gain coefficient K based on these parameters. ang Damping coefficient K sf The engine valve opening command u of the interceptor is calculated; the engine valve control module executes the engine valve actuation according to the opening command u.

[0015] Furthermore, the control parameter determination module determines the parameters based on the attitude angle command θ. c The attitude angle deviation Δθ is calculated based on the PD control law, and the gain coefficient K used for stabilizing the interceptor's attitude is used for control. angDamping coefficient K sf Specifically, it includes:

[0016]

[0017]

[0018] Where, attitude angle deviation Δθ=θ c -θ, k1 is the gain coefficient that is constant under linear error e1, ζ is the closed-loop damping coefficient of the control system, β is the proportional factor, e1=1 / k1, e2=θ c / β is the threshold for switching control parameters based on error, and a3 is the angular acceleration generated by a unit opening of the engine valve.

[0019] Furthermore, the value of the gain coefficient k1 is the same as... The deviation is a value within the specified range, where ω n The natural frequency of the control system is used; the closed-loop damping coefficient ζ of the control system is between 1.0 and 2.0; the proportional factor β is greater than |Δθ / e1.

[0020] Furthermore, the engine valve opening command u = sat(x), where sat(x) is a saturation function.

[0021]

[0022] Where x is an intermediate variable, x = K ang ×Δθ-K sf ×ω.

[0023] This invention discloses a missile variable structure attitude optimal control method and system. It uses PD control law to determine the control parameters for stabilizing the interceptor attitude, thereby reducing response oscillations and accelerating the transition process of the control system, which is conducive to the system quickly reaching stability. When there is a large error, small gain and small damping are used to achieve the bang-bang optimal control effect with the goal of speed. When there is a small error, constant coefficient linear control is used to improve steady-state performance by avoiding oscillations and overshoot. Attached Figure Description

[0024] Figure 1 The diagram below shows the block diagram of the time-optimal variable damping and variable gain attitude control method for the direct force adjustable interceptor provided by this invention.

[0025] Figure 2 This is a comparison chart of simulation results in the small command attitude angle response process between cases where the present invention is not used and cases where the method of the present invention is used.

[0026] Figure 3This is a comparison chart of simulation results in the large command attitude angle response process between cases where the present invention was not used and cases where the method of the present invention was used. Detailed Implementation

[0027] The present invention will be further described below with reference to the accompanying drawings and embodiments.

[0028] In one embodiment of the present invention, a six-degree-of-freedom full-parameter simulation is used to illustrate the implementation effect. During the simulation, 0.5° and 40° step commands are added to the pitch channel respectively.

[0029] In this implementation case, Figure 1 This is a flowchart of a time-optimal attitude control method for a direct force adjustable interceptor. The main control structure is a PD control structure. Conventional PD control uses a constant gain and constant damping coefficient. This invention uses the input command θ... c The current attitude angle deviation Δθ can be dynamically adjusted by the gain coefficient K. ang and damping coefficient K sf The control quantity u is obtained, and then u is assigned to different nozzle valves to execute commands, achieving overshoot-free and rapid tracking of commands of different magnitudes. The specific workflow is described as follows:

[0030] Step 1: The sensitive element processing unit measures the attitude angular velocity ω, the strapdown inertial navigation calculation unit calculates the attitude angle θ, and the guidance law gives the attitude angle command θ. c The signal is sent to the attitude control loop. In the simulation of this implementation case, θ... c The angles are 0.5° and 40° respectively.

[0031] Step 2: According to the attitude angle command θ c The attitude angle deviation Δθ is used to calculate the loop control parameter K for stabilizing the interceptor's attitude. ang K sf Gain coefficient Damping coefficient Where, attitude angle deviation Δθ=θ c -θ, k1 is the constant gain coefficient under the linear region error e1, and k1 is generally taken as... The difference is the value within the specified neighborhood, ω n ζ is the natural frequency of the control system, typically ranging from 5 to 8; ζ is the closed-loop damping coefficient of the control system, typically ranging from 1.0 to 2.0; β is the proportional factor, typically greater than |Δθ| / e1; e1 = 1 / k1, e2 = θ c / β is the threshold for switching control parameters based on error, and a3 is the angular acceleration generated by a unit opening of the attitude control valve. In the simulation of this implementation case, a3 is 80.3557s. -2 k1 is 1.3745, ζ is 1.025, and β is 32.1501.

[0032] Step 3: Based on the attitude angular velocity ω obtained in Step 1 and the attitude angular deviation Δθ and control parameter K obtained in Step 2... ang K sf Calculate the corresponding engine valve opening command u = sat(K) ang ×Δθ-K sf ×ω), where sat(x) is the saturation function. x is an intermediate variable, x = K ang ×Δθ-K sf ×ω.

[0033] Step 4: The engine valves actuate according to the opening command u, achieving continuously adjustable attitude control thrust and precise attitude tracking control. The valve opening limit is 0 to 1.

[0034] Accordingly, the present invention also proposes a time-optimal attitude control system for a direct force adjustable interceptor, which includes an attitude and command acquisition module, a control parameter determination module, an engine valve command determination module, and an engine valve control module.

[0035] The attitude and command acquisition module acquires the interceptor's attitude angular velocity ω, attitude angle θ, and attitude angle command θ. c .

[0036] The control parameter determination module determines the parameters based on the attitude angle command θ. c The attitude angle deviation Δθ is used to calculate the control parameter K for stabilizing the interceptor's attitude. ang K sf Specifically, this includes:

[0037] Gain coefficient Damping coefficient

[0038] Where, attitude angle deviation Δθ=θ c -θ, k1 is a constant gain coefficient under linear region error e1, and the value of k1 is related to ω. n 2 The deviation of / a3 is within the specified range, where ω n Let be the natural frequency of the control system; ζ be the closed-loop damping coefficient of the control system, with a value between 1.0 and 2.0; β be the proportional factor, with a value greater than |Δθ / e1; e1 = 1 / k1, e2 = θ c / β is the threshold for switching control parameters based on error, and a3 is the angular acceleration generated by the attitude control valve per unit opening.

[0039] The engine valve command determination module determines the attitude angular velocity ω, the attitude angle deviation Δθ, and the control parameter K based on these parameters. ang Ksf Calculate the opening command u of the interceptor's engine valve; specifically, the engine valve opening command u = sat(x), where sat(x) is a saturation function.

[0040] Where x is an intermediate variable, x = K ang ×Δθ-K sf ×ω.

[0041] The engine valve control module executes engine valve actuation according to the opening command u, thereby achieving continuous and adjustable attitude control thrust.

[0042] Based on the above steps for time-optimal attitude control of the direct force adjustable interceptor, a six-degree-of-freedom full-parameter simulation is performed. Attitude angle commands below 10° are considered small commands, while those above are considered large commands. The simulation results for the attitude angle response to small commands are as follows: Figure 2 As shown in the figure, the rise time (90%) of the traditional PID control algorithm is 0.38s, and the overshoot is 0.069%; while the rise time of the algorithm of this invention is 0.24s, and the overshoot is 0.0%. The simulation results of the large command attitude angle response are as follows: Figure 3 As shown in the figure, the rise time (90%) of the traditional PID control algorithm is 0.98s, and the overshoot is 44.05%; while the rise time of the algorithm of this invention is 1.11s, and the overshoot is 0.43%. This demonstrates that the time-optimal attitude control method for a direct force adjustable interceptor described in this invention has better dynamic quality and steady-state performance than the traditional PID control algorithm under both large and small command input conditions.

[0043] Although the present invention has been disclosed above with reference to preferred embodiments, it is not intended to limit the present invention. Any person skilled in the art can make possible changes and modifications to the technical solutions of the present invention by utilizing the methods and techniques disclosed above without departing from the spirit and scope of the present invention. Therefore, any simple modifications, equivalent changes and alterations made to the above embodiments based on the technical essence of the present invention without departing from the content of the technical solutions of the present invention shall fall within the protection scope of the technical solutions of the present invention.

Claims

1. A time-optimal attitude control method for a direct force adjustable interceptor, characterized in that, include: Step 1: Obtain the interceptor's attitude angular velocity ω, attitude angle θ, and attitude angle command θ. c ; Step 2: According to the attitude angle command θ c And calculate the attitude angle deviation Δθ based on the attitude angle θ, and then calculate the attitude angle command θ. c The attitude angle deviation Δθ is calculated using the PD control law to obtain the gain coefficient K for stabilizing the interceptor's attitude. ang Damping coefficient K sf ; Step 3: Based on the attitude angular velocity ω, the attitude angular deviation Δθ, and the gain coefficient K ang Damping coefficient K sf Calculate the interceptor's engine valve opening command u; Step 4: Execute the engine valve actuation according to the opening command u; In step two, the step of using the attitude angle command θ c The attitude angle deviation Δθ is calculated based on the PD control law, and the gain coefficient K used for stabilizing the interceptor's attitude is used for control. ang Damping coefficient K sf Specifically, it includes: Where, attitude angle deviation Δθ=θ c -θ, k1 is the gain coefficient that is constant under linear error e1, ζ is the closed-loop damping coefficient of the control system, β is the proportional factor, e1=1 / k1, e2=θ c / β is the threshold for switching control parameters based on error, and a3 is the angular acceleration generated by a unit opening of the engine valve.

2. The method according to claim 1, characterized in that, The gain coefficient k1 takes the value of... The deviation is within the specified range.

3. The method according to claim 1, characterized in that, Where ω n The natural frequency of the control system is used; the closed-loop damping coefficient ζ of the control system is between 1.0 and 2.0; the proportional factor β is greater than |Δθ| / e1.

4. The method according to claim 1, characterized in that, In step three, the engine valve opening command u = sat(x), where sat(x) is a saturation function. Where x is an intermediate variable, x = K ang ×Δθ-K sf ×ω.

5. A time-optimal attitude control system for a direct force adjustable interceptor, characterized in that, include: The system includes an attitude and command acquisition module, a control parameter determination module, an engine valve command determination module, and an engine valve control module; among which... The attitude and command acquisition module acquires the interceptor's attitude angular velocity ω, attitude angle θ, and attitude angle command θ. c ; The control parameter determination module determines the parameters based on the attitude angle command θ. c And calculate the attitude angle deviation Δθ based on the attitude angle θ, and then calculate the attitude angle command θ. c The attitude angle deviation Δθ is calculated using the PD control law to obtain the gain coefficient K for stabilizing the interceptor's attitude. ang Damping coefficient K sf ; The engine valve command determination module determines the attitude angular velocity ω, the attitude angle deviation Δθ, and the gain coefficient K based on these parameters. ang Damping coefficient K sf Calculate the opening command u of the interceptor engine valve; The engine valve control module executes engine valve actuation according to the opening command u; The control parameter determination module determines the control parameters based on the attitude angle command θ. c The attitude angle deviation Δθ is calculated based on the PD control law, and the gain coefficient K used for stabilizing the interceptor's attitude is used for control. ang Damping coefficient K sf Specifically, it includes: Where, attitude angle deviation Δθ=θ c -θ, k1 is the gain coefficient that is constant under linear error e1, ζ is the closed-loop damping coefficient of the control system, β is the proportional factor, e1=1 / k1, e2=θ c / β is the threshold for switching control parameters based on error, and a3 is the angular acceleration generated by a unit opening of the engine valve.

6. The system according to claim 5, characterized in that, The gain coefficient k1 takes the value of... The deviation is within the specified range.

7. The system according to claim 5, characterized in that, Where ω n The natural frequency of the control system is used; the closed-loop damping coefficient ζ of the control system is between 1.0 and 2.0; the proportional factor β is greater than |Δθ| / e1.

8. The system according to claim 5, characterized in that, The engine valve opening command is u = sat(x), where sat(x) is a saturation function. Where x is an intermediate variable, x = K ang ×Δθ-K sf ×ω.

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