A novel composite stabilization control method for highly statically unstable guided rockets

Abstract

This invention discloses a novel composite stabilization control method for highly statically unstable guided rockets. First, a damping loop is designed, followed by a pseudo-angle of attack stabilization loop, and then a lead-lag correction network is designed to form the composite stabilization control loop. This invention effectively solves the control design challenges of highly statically unstable guided rockets and exhibits strong robustness to time delays, parameter uncertainties, and unmodeled dynamics present in guided rockets.

Description

Technical Field

[0001] This invention belongs to the field of rocket technology, specifically relating to a novel composite stabilization control method for highly statically unstable guided rockets. Background Technology

[0002] In recent years, new types of guided rockets, such as lightweight mission payloads and separable high-lift-body payloads, have developed rapidly and possess immense value, attracting widespread attention from researchers in aerospace engineering and flight control fields. However, the static instability of these new guided rockets will increase significantly. Under the influence of various factors, including parameter uncertainties in the guided rocket model and time delays in input and state, the design of the stable control system for guided rockets presents a challenge. Considering both rapid and robust control requirements, a high-gain damped control design and a control scheme based on pseudo-angle of attack feedback and lead-lag correction network can achieve the system's static stability requirements and optimal matching performance of the guidance loop. External loops such as overload and trajectory tilt angle can be connected to achieve precise and stable control of external loop variables under different flight environments. Summary of the Invention

[0003] To overcome the shortcomings of existing technologies, this invention provides a novel composite stabilization control method for highly statically unstable guided rockets. First, a damping loop is designed, followed by a pseudo-angle of attack stabilization loop, and then a lead-lag correction network is designed to form the composite stabilization control loop. This invention effectively solves the control design challenges of highly statically unstable guided rockets and exhibits strong robustness against time delays, parameter uncertainties, and unmodeled dynamics inherent in guided rockets.

[0004] The technical solution adopted by this invention to solve its technical problem is as follows:

[0005] Step 1: Damping circuit design;

[0006] The damping circuit is used to suppress the initial launch disturbance of the rocket and ensure the stability of the projectile's attitude.

[0007] The open-loop transfer function of the damping circuit is:

[0008] (1)

[0009] The closed-loop transfer function of the damping circuit is:

[0010] (2)

[0011] in All of these are rocket dynamic coefficients. Indicates the control gain of the damping loop. Represent complex variables; Substituting into formula (2) yields the open-loop frequency response. Represents the imaginary unit. Indicates angular frequency;

[0012] Given the ideal inner loop crossing frequency The control gain of the damping loop is obtained as follows:

[0013]

[0014] Its simplified form is ;

[0015] Step 2: Design of pseudo-angle of attack stabilization loop;

[0016] The open-loop transfer function of the pseudo-angle of attack stabilization loop is:

[0017] (3)

[0018] The closed-loop transfer function of the pseudo-angle of attack stabilization loop is:

[0019] (4)

[0020] in, Gain for pseudo-angle of attack control;

[0021] Step 3: Design of the lead-lag compensation network;

[0022] The closed-loop transfer function of the composite stability-enhancing control loop is:

[0023] (5)

[0024] The transfer function of the lead compensation is: ,parameter , For the desired increase in leading phase angle, , All are lead correction factors, among which The transfer function of the hysteresis correction is , , All are lag correction factors;

[0025] Step 4: External control loop design;

[0026] For the three-ring tilt control, the climb flight phase from launch to the ballistic apex is carried out using tilt control to make the guided rocket fly according to the predetermined program angle;

[0027] The closed-loop transfer function of the tilt angle three-loop control loop is:

[0028]

[0029] in, This is the gain for tilt angle control.

[0030] Furthermore, in the tilt angle three-loop control, the open-loop cutoff frequency of the tilt angle three-loop control loop is 3 to 5 times the closed-loop bandwidth of the composite stabilization control loop.

[0031] The beneficial effects of this invention are as follows:

[0032] 1. This invention can effectively solve the control design problem of highly statically unstable guided rockets and has strong robustness to time delays, parameter uncertainties, and unmodeled dynamics in guided rockets.

[0033] 2. This invention is mainly used for the static instability control of guided rockets. Compared with traditional composite stabilization control methods, it can further improve the composite stabilization effect on projectiles with large static instability, effectively improve the stability margin of the entire closed-loop control system, and the method is simple and easy to implement, which is conducive to engineering implementation. It can be widely used in the design of various guided rocket control systems and has broad application prospects. Attached Figure Description

[0034] Figure 1 This is a block diagram of the damping control structure of the present invention.

[0035] Figure 2 This is a block diagram of the pseudo-angle of attack stabilization loop structure of the present invention.

[0036] Figure 3 This is a block diagram of the composite stabilization control loop of the present invention.

[0037] Figure 4 This is a block diagram of the tilt angle three-loop control circuit structure of the present invention.

[0038] Figure 5 This is a flowchart of the method of the present invention.

[0039] Figure 6(a) shows the frequency domain response curve of the damping circuit + pseudo angle of attack stabilization circuit in an embodiment of the present invention.

[0040] Figure 6(b) shows the frequency domain response curve of the damping circuit + pseudo angle of attack stabilization circuit + lead-lag correction network in the embodiment of the present invention.

[0041] Figure 7 This is a comparison diagram of the time-domain step response curves of the method of the present invention and the traditional method in an embodiment of the present invention. Detailed Implementation

[0042] The present invention will be further described below with reference to the accompanying drawings and embodiments.

[0043] like Figure 5As shown, this invention proposes a novel composite stabilization control method for highly statically unstable guided rockets, addressing the problem of large static instability control, such as lightweight payloads and separable high-lift-body payloads. The technical solution is as follows:

[0044] Step 1: Damping circuit design;

[0045] The damping circuit is used to suppress the initial launch disturbance of the rocket and ensure the stability of the projectile's attitude; the damping control structure is as follows: Figure 1 As shown.

[0046] The open-loop transfer function of the damping circuit is:

[0047] (1)

[0048] The closed-loop transfer function of the damping circuit is:

[0049] (2)

[0050] Will Substituting into formula (2) yields the open-loop frequency response;

[0051] Given the ideal inner loop crossing frequency The control gain of the damping loop is obtained as follows:

[0052]

[0053] Its simplified form is ;

[0054] Step 2: Design of pseudo-angle of attack stabilization loop;

[0055] To meet the requirements of fast and robust control, the pseudo-angle of attack stabilization loop design method should prioritize ensuring that the gain margin of the large statically unstable system meets the requirements. The phase margin can be supplemented by a lead-lag compensation network. The pseudo-angle of attack stabilization loop structure is as follows: Figure 2 As shown.

[0056] The open-loop transfer function of the pseudo-angle of attack stabilization loop is:

[0057] (3)

[0058] The closed-loop transfer function of the pseudo-angle of attack stabilization loop is:

[0059] (4)

[0060] Step 3: Design of the lead-lag compensation network;

[0061] Based on the design results of step 2, a lead-lag compensation network is designed to ensure that the amplitude and phase margin of the large statically unstable system meet the requirements.

[0062] The closed-loop transfer function of the composite stability-enhancing control loop is:

[0063] (5)

[0064] The transfer function of the lead compensation is: The transfer function of the hysteresis correction is The structure of the composite stabilization control loop is as follows: Figure 3 As shown.

[0065] By comprehensively utilizing the amplitude attenuation of the lag network and the phase lead of the lead network, the open-loop frequency characteristics of the system are modified, thereby improving the stability of the entire system.

[0066] The damping loop, the pseudo-angle of attack stabilization loop, and the lead-lag compensation network together constitute a composite stabilization control loop. By integrating the static and dynamic gains of the system, the parameters of the correction filter network, and considering various random errors, the margin of the large statically unstable system meets the requirements and suppresses the influence of various disturbances on the closed-loop control system.

[0067] Step 4: External control loop design;

[0068] For the tilt-angle three-loop control, the climb phase from launch to the trajectory apex is characterized by tilt-angle control, ensuring the guided rocket flies at a predetermined angle. The tilt-angle three-loop control loop structure is as follows: Figure 4 As shown.

[0069] The closed-loop transfer function of the tilt angle three-loop control loop is:

[0070]

[0071] in, This is the gain for tilt angle control.

[0072] In tilt angle three-loop control, the open-loop cutoff frequency of the tilt angle three-loop control loop is made to be 3 to 5 times the closed-loop bandwidth of the composite stabilization control loop.

[0073] Example:

[0074] The invention will now be described in further detail with reference to a certain type of guided rocket weapon system.

[0075] Step 1: Design the damping circuit:

[0076] Select the statically unstable ballistic characteristic points of the guided rocket's active phase. , , , Given the ideal inner loop crossing frequency .

[0077] but ;

[0078] Step 2: Design of pseudo-angle of attack stabilization circuit:

[0079] The damping circuit gain is ,Pick =2.5927, Figure 6(a) shows the frequency domain response curve of the damping loop + pseudo-angle of attack stabilization loop, and the open-loop gain margin can be seen. Phase margin The gain margin meets the requirements (>6dB), but the phase margin does not meet the requirements (>35°), and needs to be corrected by a lead-lag network.

[0080] Step 3: Design of the lead-lag compensation network:

[0081] The parameters for the lead-lag compensation network are selected as follows: The required lead phase angle. ,but , , , Figure 6(b) shows the frequency domain response curves of the damping loop + pseudo-angle of attack stabilization loop + lead-lag compensation network, where the open-loop gain margin is... Phase margin It is evident that after adding the lead-lag compensation network, the system is stable at the static instability point, and both the gain margin and phase margin meet the requirements.

[0082] Step 4: Tilt Angle Three-Loop Control Loop Design:

[0083] Tilt control gain Derived from the design. For example... Figure 7 As shown, after adding the lead-lag compensation network, the system is stable at the static instability point, and the response time is improved compared with the traditional damping + pseudo-angle of attack stabilization method.

Claims

1. A novel composite stabilization control method for a highly statically unstable guided rocket, characterized in that, Includes the following steps: Step 1: Damping circuit design; The damping circuit is used to suppress the initial launch disturbance of the rocket and ensure the stability of the projectile's attitude. The open-loop transfer function of the damping circuit is: (1) The closed-loop transfer function of the damping circuit is: (2) in All of these are rocket dynamic coefficients. Indicates the control gain of the damping loop. Represent complex variables; Substituting into formula (2) yields the open-loop frequency response. Represents the imaginary unit. Indicates angular frequency; Given the ideal inner loop crossing frequency The control gain of the damping loop is obtained as follows: ； Its simplified form is ; Step 2: Design of pseudo-angle of attack stabilization loop; The open-loop transfer function of the pseudo-angle of attack stabilization loop is: (3) The closed-loop transfer function of the pseudo-angle of attack stabilization loop is: (4) in, Gain for pseudo-angle of attack control; Step 3: Design of the lead-lag compensation network; The closed-loop transfer function of the composite stability-enhancing control loop is: (5) The transfer function of the lead compensation is: ,parameter , For the desired increase in leading phase angle, , All are lead correction factors, among which The transfer function of the hysteresis correction is , , All are lag correction factors; Step 4: External control loop design; For the three-ring tilt control, the climb flight phase from launch to the ballistic apex is carried out using tilt control to make the guided rocket fly according to the predetermined program angle; The closed-loop transfer function of the tilt angle three-loop control loop is: ； in, This is the gain for tilt angle control.

2. The novel composite stabilization control method for a highly statically unstable guided rocket according to claim 1, characterized in that, In the aforementioned tilt angle three-loop control, the open-loop cutoff frequency of the tilt angle three-loop control loop is 3 to 5 times the closed-loop bandwidth of the composite stabilization control loop.

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