A method for automatically designing control parameters of a guided weapon autopilot

Abstract

The application discloses a kind of guided weapon autopilot control parameter automatic design method.The application can greatly improve the design efficiency of autopilot control parameter, and speed up the design and development progress of guided weapon control system.The application first selects feature points on uncontrolled trajectory, then builds particle model at each feature point, and independently designs the autopilot control parameter at each feature point;The application gives the typical structure of overload autopilot and attitude autopilot, and the designer can transform into appropriate autopilot structure by parameter setting according to specific needs;Then by obtaining the open-loop and closed-loop transfer function of the inner and outer loops of the autopilot, the static stability at the feature point is automatically determined, and a correction network is added to the static unstable state;Finally, the autopilot inner and outer loop control parameters are automatically designed based on frequency domain performance and time domain performance.The actual project flight verification has good engineering application effect.

Description

Technical Field

[0001] This invention relates to the field of ammunition guidance and control technology, specifically to an automatic design method for control parameters of a guided weapon autopilot, applicable to guided weapons and equipment such as missiles, guided projectiles, and guided rockets. Background Technology

[0002] In modern warfare, guided weapons can precisely strike various combat targets and are being widely researched and improved by countries around the world. Unlike unguided munitions and weapons, the guidance and control system of guided weapons can be divided into two stages: guidance and control. In the guidance stage, the weapon's guidance system measures the distance and line-of-sight angular velocity between the weapon and the target, and collects information such as the target's position and velocity. This information is then processed to generate guidance commands. In the control stage, the weapon's control system takes the weapon itself as the controlled object. It can overcome interference from various uncertainties, processes the tracking commands from the guidance system and the sensor signals from the projectile itself, and generates servo control commands to control the projectile's flight. The combined action of the guidance and control systems enables guided weapons to accurately hit their targets.

[0003] The autopilot is a crucial component of the guided weapon control system. The operational environment of guided weapons is a complex, nonlinear, and time-varying environment, making modeling extremely difficult. Flight altitude, speed, heading, atmospheric conditions, and other factors significantly influence the flight attitude of the guided weapon, and these influences must be overcome by the autopilot. As a vital part of the guided weapon control system, the autopilot is designed because guided weapons have long flight times, wide flight airspaces, and large speed variations. The autopilot design involves a large number of feature points, and traditional manual point-by-point design methods are labor-intensive, inefficient, and limit the overall development progress. Especially during the development and demonstration phase, which may involve multiple aerodynamic, structural, dynamic, and ballistic schemes, the number of feature points in the autopilot design further increases, severely impacting the overall optimization process and becoming a bottleneck restricting the design of the entire system. Summary of the Invention

[0004] In view of this, the present invention provides an automatic design method for control parameters of an autopilot for guided weapons, which can significantly improve the design efficiency of autopilot control parameters and has good engineering application effects.

[0005] The automatic design method for control parameters of the guided weapon autopilot of the present invention includes:

[0006] Step 1: Select feature points on the flight trajectory of the unguided ballistic trajectory of the guided weapon; obtain the dynamic coefficients of each feature point based on the aerodynamic data issued by the overall department;

[0007] Step 2: For each feature point, design the corresponding autopilot control parameters for that feature point, specifically as follows:

[0008] S21, Build a mass model at the feature point; Based on the mass model and the autopilot structure, obtain the open-loop transfer function and closed-loop transfer function of the autopilot at the feature point, where the inner loop is the damping loop of the autopilot and the outer loop is the overload loop of the autopilot.

[0009] S22, determine the static stability of the guided weapon at the feature point; if it is statically stable, design the internal and external loop control parameters according to the steady-state margin index of the autopilot; if it is statically unstable, first design a correction network to transform the statically unstable state into a statically stable state, and then design the internal and external loop control parameters according to the steady-state margin index.

[0010] S23: Based on the control parameters of the inner and outer loops and the closed-loop transfer function of the outer loop, calculate the frequency domain and time domain performance of the autopilot; determine whether the frequency domain and time domain performance meet the performance index requirements. If the index requirements are met, complete the autopilot control parameter design at this feature point; if the index requirements are not met, adjust the control parameters of the inner and outer loops and repeat S23 until the index requirements are met.

[0011] Step 3: Traverse all feature points and complete the design of autopilot control parameters at all feature points, thus completing the design of autopilot control parameters for the guided weapon.

[0012] A better approach is to select feature points based on the guided weapon's flight altitude and flight motion parameters.

[0013] Preferred flight motion parameters are Mach number, flight speed, or dynamic pressure.

[0014] Preferably, the pitch and yaw channels adopt a three-loop autopilot structure with PI correction; the roll channel adopts an attitude autopilot structure with PI correction; through parameter setting, the three-loop autopilot structure with PI correction and the attitude autopilot structure with PI correction can be transformed into other types of autopilot mechanisms.

[0015] Preferably, in the pitch and yaw channels, the transfer function of the inner loop correction network is (s+A) / (s+B), and the transfer function of the outer loop PI correction is (s+K). i ) / s;

[0016] Let the correction network parameters A=0, B=0, and the external loop control parameter K i =0, at this time the controller structure is a classic two-circuit overload controller;

[0017] Let the correction network parameters A=0, B=0, and the external loop control parameter Ki >0, at this time the controller structure is a classic two-circuit overload controller with PI correction;

[0018] Let the correction network parameters A > 0 and B = 0, and the external loop control parameter K i >0, at this time the controller structure is a classic three-circuit overload controller with PI correction;

[0019] Let the correction network parameters A > B > 0, and the external loop control parameter K i >0, at this time the controller structure is a pseudo angle-of-attack three-loop controller with PI correction;

[0020] In the roll channel, the transfer function of the outer loop PI correction is (s+K) γi Let the external loop control parameter k / s be ) / s. γi =0, at this time the driving instrument structure is a typical attitude driving instrument structure.

[0021] In the pitch, yaw, and roll channels, if an autopilot structure with PI correction is used, the design inner loop control parameter K... ω K ωx External loop control parameter K A k γ During the process, a 1-2 dB amplitude margin and a 5-10° phase margin are left to cope with the margin reduction caused by the integrator.

[0022] Ideally, for a statically stable state, the internal circuit parameter K of the overload controller is... ω External loop control parameter K A The internal loop control parameter K of the attitude driving system ωx External loop control parameter k γ The design process is as follows:

[0023] S221: Set the initial value of control parameter K1; the initial value of K1 can be set to 1~5, and the magnitude of the initial value only affects the number of loops; K1 = K ω K A K ωx k γ ;

[0024] S222: Calculate the steady-state margin of the loop corresponding to the current control parameter value, and compare the current steady-state margin with the design specifications. If the design specifications are met, execute S223; otherwise, multiply K1 by the coefficient G1 and repeat S222 until the design specifications are met or the maximum number of loops is reached, then execute S223. The maximum number of loops can be set to 25 to prevent the program from entering an infinite loop. The coefficient G1 is 0.5 to 0.8, and this design uses a coarse-grained selection.

[0025] S223: Let K1 be multiplied by coefficient G2, and then multiplied by coefficient G3; the coefficient G2 is the reciprocal of coefficient G1; the coefficient G3 is 0.95 to 0.99; the closer the coefficient G3 is to 1, the more calculations are performed, and the more accurate the parameter design value is.

[0026] S224: Calculate the loop steady-state margin corresponding to the current control parameter value, and compare the current steady-state margin with the design specifications. If the design specifications are met, proceed to S235; otherwise, let K... ω Multiply by coefficient G3, repeat S224 until the design specifications are met or the maximum number of iterations is reached, then execute S235. This design is a fine-grained value selection.

[0027] S225, using the current K1 as the output, completes the design of this control parameter.

[0028] Preferably, for statically unstable states, an inner loop correction network needs to be designed first, followed by the design of other control parameters; the transfer function of the inner loop correction network is (s+A) / (s+B), where B = 0.2~0.4; the design process of the correction network parameter A is as follows:

[0029] S221A: Set the initial value of the correction network parameter A to B, and the inner loop control parameter to 1;

[0030] S222A: Multiply parameter A by coefficient G4 to obtain the upper and lower limits of the gain margin and the gain margin range of the open-loop transfer function of the current inner loop; the coefficient G4 is 1.2 to 1.5;

[0031] S223A: Continue to multiply parameter A by coefficient G4 to obtain the gain margin range of the open-loop transfer function of the current inner loop, and compare it with the gain margin range of S222A; if the range becomes smaller, execute S224; if the range increases, repeat S223A until the range becomes smaller or the maximum number of loop executions is reached, then execute S224A.

[0032] S224A: Divide parameter A by coefficient G4 to complete the design of parameter A and save the magnitude margin range of the current inner loop open-loop transfer function.

[0033] Ideally, for statically unstable states, after designing the calibration network parameters, the internal and external loop control parameters should be designed, including the internal loop control parameter K of the overload controller. ω External loop control parameter K A The internal loop control parameter K of the attitude driving system ωx External loop control parameter k γ The design process is as follows:

[0034] S225A: Set the initial value of control parameter K′1; the initial value of K′1 can be set to 1~5, and the magnitude of the initial value only affects the number of loops; K′1 = K ω K A K ωx K γ ;

[0035] S226A: Calculate the upper limit of the gain margin of the open-loop transfer function corresponding to the current control parameter value, and determine whether it is greater than half of the gain margin interval stored in S224A; if yes, execute S227A; if no, multiply parameter K′1 by coefficient G5, repeat S226A until the maximum number of loops is met or reached, then execute S227A; the maximum number of loops can be set to 25 to prevent the program from entering an infinite loop; the coefficient G5 is 0.5 to 0.8, and this design uses a coarse-grained selection;

[0036] S227A: Multiply parameter K′1 by coefficient G6, then multiply by coefficient G7; the coefficient G6 is the reciprocal of coefficient G5; the coefficient G7 is 0.95 to 0.99; the closer coefficient G7 is to 1, the more calculations are performed, and the more accurate the parameter design value is.

[0037] S228A: Calculate the upper limit of the gain margin of the open-loop transfer function corresponding to the current control parameter value, and determine whether it is greater than half of the gain margin interval stored in S224A; if yes, execute S229A; if no, multiply parameter K′1 by coefficient G7, repeat S228A until the condition is met or the maximum number of cycles is reached, and then execute S229A. This design is a fine-grained value selection.

[0038] S229A: Using the current K′1 as the output, complete the design of this control parameter.

[0039] The preferred PI correction parameter K of the overload controller i PI correction parameter k of attitude driving system γi The design process is as follows:

[0040] S231: Set the initial value of parameter K2; K2 = K i k γi ;

[0041] S232: Substitute K2 into the open-loop transfer function of the outer loop, calculate the steady-state margin of the current open-loop transfer function of the outer loop, and determine whether the current steady-state margin meets the frequency domain design specifications. If it does, execute S233; if it does not, multiply K2 by the coefficient G8, repeat S232, until it meets the specifications or the maximum number of iterations is reached, then execute S233; where the coefficient G8 is 0.9 to 0.95;

[0042] S233: Substitute K2 into the closed-loop transfer function of the outer loop, obtain the time-domain performance of the current outer loop, and determine whether the current time-domain performance can meet the time-domain design specifications. If it can, execute S234; if it cannot, multiply K2 by the coefficient G8, repeat S233, until it meets or reaches the maximum number of loops, and then execute S234.

[0043] S234: Use the current K2 as the output to complete the design of this parameter.

[0044] Beneficial effects:

[0045] (1) This invention first selects feature points on the uncontrolled trajectory, then builds mass models at each feature point, and independently designs the autopilot control parameters at each feature point. By obtaining the open-loop and closed-loop transfer functions of the autopilot's internal and external loops, the static stability at the feature point can be automatically determined. A correction network is added to the autopilot's internal loop in the statically unstable state to transform it into a statically stable state. Then, based on the frequency domain performance and time domain performance, the control parameters of the autopilot at statically stable and statically unstable points are automatically designed. This invention can significantly improve the design efficiency of autopilot control parameters and has good engineering application effects.

[0046] (2) Autopilots are divided into overload autopilots and attitude autopilots. Both autopilots can adopt a three-loop autopilot structure with PI correction. Through parameter setting, the three-loop overload autopilot structure with PI correction can be converted into a classic two-loop overload autopilot (when the correction network parameters A=0, B=0, and the outer loop control parameter K...). i =0), a classic two-loop overload control system with PI correction (when the correction network parameters A=0, B=0, and the external loop control parameter K = 0). i =0), a classic three-loop overload control system with PI correction (when the correction network parameter A > 0, B = 0, and the outer loop control parameter K = 0). i =0), pseudo-angle of attack three-loop autopilot with PI correction (when correction network parameter A>B>0, external loop control parameter K) i =0); The three-loop attitude control system with PI correction can also be converted into a classic attitude control system (when the external loop control parameter k γi =0); It can be applied to the control parameter design of various autopilots and has good versatility.

[0047] (3) By adopting a cyclical iterative approach, the values ​​of control parameters are gradually determined from coarse to fine, resulting in accurate and reliable design results with minimal computational burden. Attached Figure Description

[0048] Figure 1 Design process for autopilot control parameters.

[0049] Figure 2 This is a schematic diagram of the overload driving device.

[0050] Figure 3 This is a schematic diagram of the attitude driving system.

[0051] Figure 4 For the internal loop control parameter K in static steady state ω Design process.

[0052] Figure 5 For the statically stable external loop control parameter K A Design process.

[0053] Figure 6 Design process for correcting network parameters A for statically unstable states.

[0054] Figure 7 The internal loop parameter K is in a statically unstable state. ω Design process.

[0055] Figure 8 External loop control parameter K for statically unstable state A Design process.

[0056] Figure 9 For the external loop control parameter K i Design process. Detailed Implementation

[0057] The present invention will now be described in detail with reference to the accompanying drawings and embodiments.

[0058] Specific Implementation Method 1: Combination Figure 1 This specific embodiment describes an automatic design method for control parameters of a guided weapon autopilot, which includes the following steps:

[0059] Step 1: Based on the flight trajectory of the unguided ballistic trajectory of the guided weapon, select feature points that represent typical characteristics during its flight. Feature points are generally selected on the flight trajectory from the perspective of altitude and motion parameters, taking into account the flight characteristics of the guided weapon. The feature points can be selected as an m×n two-dimensional matrix, where m is the flight altitude and n is Mach, or it can be motion parameters such as flight speed and dynamic pressure.

[0060] Step 2: Calculate the dynamic coefficient of each characteristic point based on the aerodynamic parameters, structural parameters, engine thrust parameters, etc. of the guided weapon issued by the overall department.

[0061] Step 3: Set the performance indicators of the autopilot, including: steady-state margin (including amplitude margin and phase margin), closed-loop bandwidth, delay margin, damping ratio, rise time, settling time, overshoot, steady-state error, etc.

[0062] For each feature point, the corresponding autopilot control parameters are designed separately, as follows:

[0063] Step 4: Select the autopilot structure. Autopilots are divided into overload autopilots and attitude autopilots. Based on the dynamic coefficients of the feature points, construct a point mass model to obtain the open-loop and closed-loop transfer functions of the autopilot's inner and outer loops at those feature points. The inner loop refers to the damping loop, also known as the angular velocity loop. The outer loop, depending on the autopilot structure, can be divided into an overload loop or an angular position loop.

[0064] Step 5: Determine the static stability of the guided weapon at the feature point based on the transfer function: If it is statically stable, there is no need to design a correction network or the control parameters of the correction network can be set to 0. The inner loop control parameters and outer loop control parameters can be designed directly based on the steady-state margin index. If it is statically unstable, the correction network and its control parameters need to be designed first to correct the statically unstable state to a statically stable state. Then, the inner loop control parameters and outer loop control parameters are designed based on the steady-state margin index.

[0065] Step 6: Based on the control parameters of the inner and outer loops and the closed-loop transfer function of the outer loop, calculate the frequency domain and time domain performance of the autopilot, such as damping ratio, rise time, overshoot, and closed-loop bandwidth.

[0066] Step 7: Verify whether the frequency domain and time domain performance meet the design requirements. If the requirements are met, complete the autopilot control parameter design at this feature point and proceed to Step 8; if not, adjust the internal and external loop control parameters and return to Step 6.

[0067] Step 8: Traverse all feature points and repeat steps 4 to 7 until the control parameters for each feature point are designed. The autopilot control parameters design is now complete.

[0068] Specific Implementation Method Two: Combination Figure 2-3 This specific embodiment differs from step four of Specific Embodiment One in that it provides schematic diagrams of a general overload autopilot structure and an attitude autopilot structure. Designers can select control parameters and modify the autopilot structure according to project needs to meet the design requirements of the guided weapon autopilot.

[0069] The autopilot of a guided weapon includes three control channels: pitch, yaw, and roll. The pitch and yaw channels of an axisymmetric guided weapon are similar and can be simplified to pitch and yaw channels for analysis. Figure 2 A general control structure diagram for an autopilot in the pitch / yaw channel is presented, which is a typical structure of an overload autopilot with PI correction.

[0070] Among them, K ω K represents the control parameters of the internal loop of the driver's instrument, and A and B represent the design parameters of the calibration network. A K i These are the control parameters for the external circuit of the driver's instrument. yc For overload instructions, a y For overload feedback, the servo is a classic second-order circuit (damping ratio of 0.6, frequency of 17Hz), and δ represents the servo deflection angle feedback. It represents the pitch angular velocity. The transfer function of the projectile is calculated from the dynamic coefficient at this characteristic point. The transfer function of the inner loop correction network is (s+A) / (s+B), and the transfer function of the outer loop PI correction network is (s+K). i ) / s.

[0071] Designers can modify the structure of the controller by adjusting its parameters according to project requirements.

[0072] Let the correction network parameters A=0, B=0, and the external loop control parameter K i =0, at this time the controller structure is a classic two-circuit overload controller;

[0073] Let the correction network parameters A=0, B=0, and the external loop control parameter K i >0, at this time the controller structure is a classic two-circuit overload controller with PI correction;

[0074] Let the correction network parameters A > 0 and B = 0, and the external loop control parameter K i >0, at this time the controller structure is a classic three-circuit overload controller with PI correction;

[0075] Let the correction network parameters A > B > 0, and the external loop control parameter K i >0, at this time the controller structure is a pseudo angle-of-attack three-loop controller with PI correction;

[0076] It should be noted that, regardless of the type of controller structure used, the internal loop control parameter K... ω External loop control parameter K A All of these must be designed. Moreover, for statically unstable projectiles, correction network parameters A and B also need to be designed.

[0077] Figure 3 A general autopilot control structure diagram for the roll channel is presented, which is a posture autopilot with PI correction. Wherein, K... ωx K is the control parameter for the internal circuit of the driver's instrument. γ K γi These are the external circuit control parameters for the driver's instrument. γ cγ is the roll angle command, and γ is the roll angle feedback. δ represents the roll rate, the servo is a classic second-order circuit (damping ratio of 0.6, frequency of 17Hz), and δ represents the servo deflection angle feedback. The transfer function of the projectile is calculated from the dynamic coefficient at this characteristic point. In the roll channel, the external loop PI-corrected transfer function is (s+K) γi ) / s, which can make the control parameter K γi =0, at this time the control system structure is a typical attitude control system structure. Similar to an overload control system, the internal loop control parameter K ωx External loop control parameter k γ It is also something that must be designed.

[0078] It should be noted that the external loop control parameter K i / k γi Its main function is to increase the system order and eliminate steady-state error. But K i / k γi The addition of PI correction will reduce the steady-state margin of the control system. Therefore, if PI correction is to be added, the control parameter K should be designed accordingly. ω K A K ωx and k γ It is necessary to consider leaving some margin in advance. Generally, leave an amplitude margin of 1 to 2 dB and a phase margin of 5 to 10°.

[0079] Specific Implementation Method Three: Combination Figures 4-5 This specific implementation method differs from step five of the first implementation method in that it focuses on the design process of control parameters for statically stable projectiles.

[0080] First, let's introduce the internal circuit parameter K of the overload driving instrument. ω Design process:

[0081] Step 1: Set the internal loop control parameter K ω The initial value of K; ω The initial value can be set to 1 to 5, and the size of the initial value only affects the number of loops;

[0082] Step 2: Calculate the steady-state margin of the current inner loop and compare it with the design specifications. If the design specifications are met, proceed to Step 3; otherwise, let K... ω Multiply by a coefficient G1, where G1 is between 0.5 and 0.8. In this embodiment, G1 = 0.5 is selected. Repeat step two until the design target is met or the maximum number of iterations is reached, and then execute step three. The maximum number of iterations in step two is set to 50.

[0083] Step 3: Take the final K from Step 2 ωMultiply by coefficient G2, where G2 is the reciprocal of coefficient G1;

[0084] Step 4: Place K ω Multiply by a coefficient G3, which is between 0.95 and 0.99. The closer the coefficient G3 is to 1, the more calculations are performed, and the more accurate the parameter design value is. In this embodiment, G3 = 0.95.

[0085] Step 5: Calculate the current K ω The steady-state margin of the inner loop is calculated, and the current steady-state margin is compared with the design specifications. If the design specifications are met, step six is ​​executed; otherwise, step four is returned until the design specifications are met or the maximum number of iterations is exceeded, at which point step six is ​​executed. The maximum number of iterations for steps four and five is set to 50.

[0086] Step Six: If the design requirements are met, save the design results. If the maximum number of iterations is exceeded and the requirements are still not met, mark position 1 as requiring manual review. Subsequent manual review and verification are required. This design is now complete.

[0087] Static stabilized projectile overload control instrument external circuit control parameter K A The internal loop control parameter K of the attitude driving system ωx external loop control parameter k of attitude driving system γ Design process and K ω The design process is the same and will not be repeated here. It is important to note that the external loop control parameters are evaluated using the stability margin of the external loop, such as... Figure 5 As shown.

[0088] Detailed Implementation Method Four: Combination Figures 6-8 This specific implementation method differs from step five of the first implementation method in that it focuses on the design process for control parameters of a statically unstable projectile.

[0089] If the closed-loop transfer function of the projectile has poles in the right half-plane, the system is a statically unstable projectile. For a statically unstable projectile, the correction network parameters A and B should be designed first, and then the inner loop control parameter K should be designed. ω and external loop control parameter K A .

[0090] The transfer function of the inner loop correction network is (s+A) / (s+B), where B = 0.2 to 0.4. The design process for the correction network parameter A is as follows:

[0091] Step 1: Set the initial value of the calibration network parameter A, A = B, and the inner loop control parameter K. ω =1.

[0092] Step 2: Multiply parameter A by coefficient G4 to obtain the upper and lower limits of the gain margin and the gain margin range of the open-loop transfer function of the current inner loop. The coefficient G4 is 1.2 to 1.5; in this embodiment, G4 = 1.2.

[0093] Step 3: Continue multiplying parameter A by coefficient G4 to obtain the gain margin interval of the current inner loop open-loop transfer function, and compare it with the gain margin interval from Step 2. If the interval decreases, proceed to Step 4; if the interval increases, repeat Step 3 until the interval decreases or the maximum number of iterations is reached, then proceed to Step 4. Let the maximum number of iterations for Step 3 be 25.

[0094] Step 4: Divide parameter A by coefficient G4. This will result in the inner loop open-loop transfer function having the largest gain margin range. Save parameters A and B.

[0095] After completing the design of the calibration network parameters, the internal and external loop control parameters are designed, taking the internal loop control parameter K of the overload controller as an example. ω For example, the design process is as follows: Figure 7 As shown, the details are as follows:

[0096] Step 5: Set the internal loop control parameter K ω The initial values ​​are substituted into the correction network parameters A and B designed in step four. In this embodiment, K... ω The initial value is set to 1.

[0097] Step Six: Calculate the upper limit of the gain margin of the open-loop transfer function of the current inner loop, and determine whether it is greater than half of the gain margin interval obtained in Step Four. If the condition is met, proceed to Step Seven; otherwise, let parameter K... ω Multiply by a coefficient G5, where G5 is between 0.5 and 0.8; in this embodiment, G5 = 0.5 is selected. Repeat step six until the judgment condition is met or the maximum number of iterations in step six is ​​reached, then proceed to step seven. The maximum number of iterations in step six is ​​set to 50.

[0098] Step 7: Let parameter K ω Multiply by coefficient G6, then multiply by coefficient G7; the coefficient G6 is the reciprocal of coefficient G5; the coefficient G7 is 0.95 to 0.99, and in this embodiment, coefficient G7 = 0.95.

[0099] Step 8: Calculate the upper limit of the gain margin of the open-loop transfer function of the current inner loop, and determine whether it is greater than half of the gain margin interval obtained in Step 4. If the condition is met, proceed to Step 9; otherwise, let parameter K... ω Multiply by coefficient G7, repeat step eight until the judgment condition is met or the maximum number of iterations in step eight is reached, then proceed to step nine. The maximum number of iterations in step eight is set to 50.

[0100] Step 9: Save the current parameter K ω The value of represents the result of this design. If step eight exceeds the maximum number of iterations and still fails to meet the judgment condition, the flag requiring manual review will be set to 1, and subsequent manual review and verification will be required. This design is now complete.

[0101] External loop control parameter K of the statically unstable projectile overload control system A The internal loop control parameter K of the attitude driving system ωx External loop control parameter k γ Similar to the control parameter K of the inner loop in steps five to eight ω The design process will not be elaborated further. It is important to note the external loop control parameter K. A k γ During the design process, the gain margin of the open-loop transfer function of the outer loop is used for evaluation, such as... Figure 8 As shown.

[0102] Specific Implementation Method Five: Combination Figure 9 The difference between this specific implementation method and step five in the first implementation method lies in the external loop control parameter K. i Parameter design. External loop control parameter K i The design process is as follows:

[0103] Step 1: Set K i The initial value of K in this embodiment is K. i The initial value is set to 1.

[0104] Step 2: Place K i Substitute the values ​​into the open-loop transfer function of the outer loop to calculate the steady-state margin of the current open-loop transfer function; verify whether the current steady-state margin meets the design specifications. If it does, proceed to step three; otherwise, let K... i Multiply by coefficient G8, repeat step two until the maximum number of iterations is met or reached, then proceed to step three. The coefficient G8 is between 0.9 and 0.95; in this embodiment, G8 = 0.9. The maximum number of repetitions for step two is set to 20.

[0105] Step 3: Place K i Substitute the values ​​into the outer loop closed-loop transfer function to obtain the time-domain performance of the current outer loop closed-loop transfer function. If the current time-domain performance meets the design specifications, proceed to step four; otherwise, K... i Multiply by the coefficient G8, repeat step three until the maximum number of iterations is met or reached, then proceed to step four. Set the maximum number of repetitions for step three to 20.

[0106] Step 4: Save the current K iRetrieve the value and end the design. If the maximum number of iterations is exceeded and the requirements are still not met, the manual review flag should be set to 1, and the system should wait for manual review.

[0107] PI correction parameter k of attitude driving system γi Design process and PI correction parameters K of overload driving instrument i The same applies, so I won't repeat myself.

[0108] In summary, the above are merely preferred embodiments of the present invention and are not intended to limit the scope of protection of the present invention. 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. An automatic design method for control parameters of an autopilot for a guided weapon, characterized in that, include: Step 1: Select feature points on the flight trajectory of the unguided ballistic trajectory of the guided weapon; obtain the dynamic coefficients of each feature point; Step 2: For each feature point, design the corresponding autopilot control parameters for that feature point, specifically as follows: S21, Build a mass model at the feature point; Based on the mass model and the autopilot structure, obtain the open-loop transfer function and closed-loop transfer function of the autopilot at the feature point, where the inner loop is the damping loop of the autopilot and the outer loop is the overload loop of the autopilot. S22, determine the static stability of the guided weapon at this feature point; If the system is in a statically stable state, the internal and external loop control parameters are designed based on the autopilot's steady-state margin index. Specifically, for a statically stable state, the internal loop parameters of the autopilot are... External loop control parameters Inner loop control parameters of attitude control system External loop control parameters The design process is as follows: S221: Set control parameters K The initial value of 1; K 1= S222: Calculate the steady-state margin of the loop corresponding to the current control parameter value, and compare the current steady-state margin with the design specifications. If the design specifications are met, execute S223; otherwise, set... Multiply by a coefficient Repeat step S222 until the design specifications are met or the maximum number of iterations is reached, then execute step S223; the coefficient The value is 0.5~0.8; S223: Order Multiply by a coefficient Then multiply by a coefficient The coefficient coefficient The reciprocal of the coefficient; The value is 0.95~0.99; S224: Calculate the loop steady-state margin corresponding to the current control parameter value, and compare the current steady-state margin with the design target. If the design target is met, then execute S235. If the design specifications are not met, then... Multiply by a coefficient Repeat S224 until the design target is met or the maximum number of loops is reached, then execute S235. S225, in the current As output, complete the design of this control parameter; If the state is statically unstable, a correction network is first designed to transform it into a statically stable state. Then, the control parameters for the inner and outer loops are designed based on the steady-state margin index. Specifically, for a statically unstable state, an inner loop correction network needs to be designed first. The transfer function of the inner loop correction network is... , = 0.2 ~ 0.4; Correct network parameters The design process is as follows: S221A: Setting calibration network parameters The initial value is The internal loop control parameter is 1; S222A: Let the parameter Multiply by a coefficient Find the upper and lower limits of the gain margin and the gain margin interval of the open-loop transfer function of the current inner loop; the coefficients It is 1.2~1.5; S223A: Continue setting parameters Multiply by a coefficient Find the gain margin range of the open-loop transfer function of the current inner loop and compare it with the gain margin range of S222A; if the range becomes smaller, execute S224; if the range increases, repeat S223A until the range becomes smaller or the maximum number of loop executions is reached, then execute S224A. S224A: Let the parameter Divide by coefficient Complete parameters The design preserves the magnitude margin range of the current inner loop open-loop transfer function; S23: Based on the control parameters of the inner and outer loops and the closed-loop transfer function of the outer loop, calculate the frequency domain and time domain performance of the autopilot; determine whether the frequency domain and time domain performance meet the performance index requirements. If the index requirements are met, complete the autopilot control parameter design at this feature point; if the index requirements are not met, adjust the control parameters of the inner and outer loops and repeat S23 until the index requirements are met. Step 3: Traverse all feature points and complete the design of autopilot control parameters at all feature points, thus completing the design of autopilot control parameters for the guided weapon.

2. The method as described in claim 1, characterized in that, Feature points are selected based on the guided weapon's flight altitude and flight motion parameters.

3. The method as described in claim 2, characterized in that, Flight motion parameters include Mach number, flight speed, or dynamic pressure.

4. The method as described in claim 1, characterized in that, The pitch and yaw channels adopt a three-loop autopilot structure with PI correction; the roll channel adopts an attitude autopilot structure with PI correction; through parameter setting, the three-loop autopilot structure with PI correction and the attitude autopilot structure with PI correction can be transformed into other types of autopilot mechanisms.

5. The method as described in claim 4, characterized in that, In the pitch and yaw channels, the transfer function of the inner loop correction network is: The external loop PI correction transfer function is ; Let the network parameters be corrected External loop control parameters At this time, the controller structure is a classic two-circuit overload controller; Let the network parameters be corrected External loop control parameters At this time, the controller structure is a classic two-circuit overload controller with PI correction; Let the network parameters be corrected External loop control parameters At this time, the controller structure is a classic three-circuit overload controller with PI correction; Let the network parameters be corrected External loop control parameters At this time, the controller structure is a pseudo-angle of attack three-loop controller with PI correction; In the roll channel, the transfer function of the outer loop PI correction is: Set the external loop control parameters At this point, the control system structure is a typical attitude control system structure.

6. The method as described in claim 5, characterized in that, In pitch, yaw, and roll modes, if an autopilot structure with PI correction is used, the internal loop control parameters need to be designed. External loop control parameters During the process, a 1-2 dB amplitude margin and a 5-10° phase margin are left.

7. The method as described in claim 1, characterized in that, For statically unstable states, after completing the design of the calibration network parameters, the design of the inner and outer loop control parameters is carried out. Among them, the inner loop control parameters of the overload controller are... External loop control parameters Inner loop control parameters of attitude control system External loop control parameters The design process is as follows: S225A: Setting control parameters The initial value; = S226A: Calculate the upper limit of the gain margin of the open-loop transfer function corresponding to the current control parameter value, and determine whether it is greater than half of the gain margin interval stored in S224A; if yes, execute S227A; if no, set the parameter... Multiply by a coefficient Repeat S226A until the maximum number of iterations is met or reached, then execute S227A; the coefficient The value is 0.5~0.8; S227A: Set parameters Multiply by a coefficient Multiply by a coefficient The coefficient coefficient The reciprocal of the coefficient; The value is 0.95~0.99; S228A: Calculate the upper limit of the open-loop transfer function gain margin corresponding to the current control parameter value, and determine whether it is greater than half of the gain margin interval stored in S224A; if yes, execute S229A; if no, set the parameter... Multiply by a coefficient Repeat S228A until the maximum number of loops is met or reached. S229A: In the current... As output, complete the design of this control parameter.

8. The method according to any one of claims 1 to 6, characterized in that, PI calibration parameters of overload control device PI calibration parameters of attitude driving system The design process is as follows: S231: Setting parameters K 2. Initial values; K 2= ; S232: Will Substituting the values ​​into the outer loop open-loop transfer function, calculate the steady-state margin of the current outer loop open-loop transfer function, and determine whether the current steady-state margin meets the frequency domain design specifications. If it does, execute S233; otherwise, set... Multiply by a coefficient Repeat S232 until the maximum number of iterations is met or reached, then execute S233; where the coefficient is... The value is 0.9~0.95; S233: Will Substitute the values ​​into the closed-loop transfer function of the outer loop to obtain the time-domain performance of the current outer loop, and determine whether the current time-domain performance meets the time-domain design specifications. If it does, execute S234; otherwise, set... Multiply by a coefficient Repeat S233 until the maximum number of loops is met or reached, then execute S234; S234: In the current As output, complete the design of this parameter.

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