A fast calculation method of trajectory parameters based on database

Abstract

The present invention discloses a database-based method for rapidly calculating trajectory parameters. The method comprises: constructing a boost-phase motion model for a boost-glide missile; setting a boost-phase flight program based on the boost-phase motion model to obtain a boost-phase terminal state; segmenting the boost-phase terminal state using an adaptive gridding method to obtain grid feature points; determining boost-phase trajectory parameters based on the boost-phase terminal state at the grid feature points, constructing a parameter database, and obtaining boost-phase trajectory parameters for the boost-glide missile by interpolating four feature points adjacent to the target's boost-phase terminal state. By using the present invention, the missile can further improve its trajectory parameter calculation speed and reduce flight altitude error when adapting to different flight missions. As a database-based method for rapidly calculating trajectory parameters, the present invention can be widely applied to the boost-phase guidance technology of missiles and launch vehicles.

Description

Technical Field

[0001] The present invention relates to the technical field of missile and carrier rocket booster guidance, and in particular to a method for quickly calculating trajectory parameters based on a database. Background Art

[0002] Early missile and launch vehicle trajectory parameter preparation took a long time and required extensive human intervention, resulting in a heavy computational burden that made it difficult to adapt to new combat modes and hindered the combat effectiveness of weaponry. Reducing launch preparation time is key to improving missile survivability and strike effectiveness, especially from mobile launch platforms. This requires rapid generation of full-range trajectories based on the current launch and target points, as well as rapid and accurate solution of relevant parameters. Existing methods for rapidly calculating firing parameters for boost-glide missiles under mobile launch conditions and for rapidly designing the ascent phase trajectory of solid-propellant launch vehicles rely on iterative methodologies for parameter solution. Due to the inherent iterative calculation process, these methods suffer from low computational efficiency, resulting in parameter preparation times that often fail to meet the requirements of new combat technical indicators. Summary of the Invention

[0003] In order to solve the above technical problems, the purpose of the present invention is to provide a method for quickly solving ballistic parameters based on a database, so that the missile can further improve the solution speed of its ballistic parameters and reduce the error of flight altitude when adapting to different flight missions.

[0004] The first technical solution adopted by the present invention is: a method for quickly calculating trajectory parameters based on a database, comprising the following steps:

[0005] Construct a boost phase motion model for a boost-glide missile;

[0006] Based on the boost phase motion model, the boost phase flight program is set to obtain the boost phase terminal state;

[0007] The terminal state of the boosting section is segmented by an adaptive grid segmentation method to obtain grid feature points.

[0008] According to the grid feature points and the terminal state of the boost phase, the trajectory data of the boost phase are determined and a data database is constructed;

[0009] Based on the data base, the trajectory data of the boost phase of the boost-glide missile are obtained by interpolating the four feature points adjacent to the terminal state of the boost phase.

[0010] Furthermore, the boost phase motion model of the boost-glide missile is constructed as follows:

[0011]

[0012] In the above formula, V represents velocity, θ represents velocity inclination, σ represents track yaw angle, v represents roll angle, φ represents latitude, λ represents longitude, r represents distance from the center of the earth, α represents angle of attack, m represents mass, and P e represents thrust, and g represents gravitational acceleration.

[0013] Furthermore, the flight procedure is specifically as follows:

[0014]

[0015] In the above formula, represents the flight program of a boost-glide missile, t 11 Indicates the end time of the vertical take-off phase of the boost-glide missile, t 12 Indicates the end time of the attack angle turning phase of the boost-glide missile, t 13 Indicates the end time of the gravity turning phase of the boost-glide missile, t 1s Indicates the end time of the fixed-axis flight phase of the boost-glide missile, t 2s Indicates the end time of the secondary flight phase of the boost-glide missile, t 3s Indicates the end time of the third stage flight of the boost-glide missile. It represents the rate of change of the secondary constant pitch angle of the boost-glide missile. Indicates the three-level constant pitch angle change rate of the boost-glide missile.

[0016] Furthermore, the step of determining the trajectory data of the boost phase based on the boost phase terminal state at the grid feature points and constructing a data database specifically includes:

[0017] The constraints of the boost phase terminal state under the maximum and minimum range conditions are determined by direct method, and the boundary ranges of the boost phase trajectory data parameters are obtained.

[0018] Based on the boundary range of the boost phase trajectory data parameters, the boost phase terminal state is segmented by an adaptive grid segmentation method to obtain grid feature points.

[0019] According to the terminal state of the boosting segment on the grid feature point, the various parameters on the grid feature point are iteratively calculated using the Newton iteration algorithm, the calculation results are output and a database of various parameters is constructed.

[0020] Furthermore, the step of iteratively calculating the various parameters on the grid feature points by using the Newton iteration algorithm, outputting the calculation results and constructing a database of various parameters specifically includes:

[0021] According to the actual requirements of the launch mission, set the accuracy threshold corresponding to each parameter;

[0022] Integrate the boost phase trajectory of the boost-glide missile to obtain the initial boost phase terminal state;

[0023] Performing a difference process on the constraint condition of the boost phase terminal state and the initial boost phase terminal state to obtain a difference value;

[0024] The difference is judged, and if it is greater than a preset accuracy threshold, a Jacobian matrix is ​​constructed based on the difference;

[0025] The Jacobian matrix is ​​iteratively calculated using the Newton iteration formula until the calculation result is less than the preset accuracy threshold, the calculation result is output and a database of various elements is constructed.

[0026] Furthermore, the Jacobian matrix is ​​specifically as follows:

[0027]

[0028] In the above formula, M k The Jacobian matrix of the boosting segment terminal parameters, α m 、 and Represents the parameters of the trajectory elements, h represents the height constraint in the constraints of the terminal state of the boost phase, v represents the velocity constraint in the constraints of the terminal state of the boost phase, θ represents the local velocity inclination constraint in the constraints of the terminal state of the boost phase, In the Newton iteration method, h represents the terminal height of the boosting segment obtained by adjusting the integral of the iteration amount; k represents the terminal height of the boosting segment obtained by substituting the initial value of the iteration into the integral, In the Newton iteration method, the terminal velocity of the boosting segment is obtained by adjusting the integral of the iteration amount, v k represents the terminal velocity of the boosting stage obtained by substituting the initial value of the iteration into the integral, In the Newton iteration method, the terminal velocity inclination angle of the boosting segment is obtained by adjusting the integral of the iteration amount, θ k It represents the terminal velocity inclination angle of the boosting phase obtained by substituting the initial value of the iteration into the integral, and δ represents a small amount.

[0029] Furthermore, the Newton iteration calculation formula is as follows:

[0030]

[0031] In the above formula, Indicates the maximum negative angle of attack of the trajectory elements in the previous iteration, Indicates the maximum negative angle of attack of the trajectory elements under the current iteration number, Indicates the rate of change of the trajectory parameters secondary program angle of the previous iteration, Indicates the rate of change of the secondary program angle of the trajectory parameters under the current iteration number, Indicates the rate of change of the trajectory parameters three-level program angle in the previous iteration, Indicates the rate of change of the trajectory parameters three-level program angle under the current iteration number, h * The terminal height of the boost phase of the target, v * represents the terminal velocity of the target during the boost phase, θ * Indicates the target's terminal velocity inclination during the boost phase.

[0032] Furthermore, the step of obtaining the boost phase trajectory elements of the boost-glide missile by interpolating four feature points adjacent to the boost phase terminal state of the target based on the element database specifically includes:

[0033] Setting the distance between the missile's starting point and target point, and determining the missile's terminal parameters using a range analytical formula, the missile's terminal parameters include the terminal altitude and speed of the boost phase target;

[0034] Based on the various metadata database, the terminal parameters of the missile are searched and processed to obtain adjacent feature points;

[0035] Interpolation processing is performed on the adjacent feature points to obtain the ballistic parameters of the boost phase of the boost-glide missile.

[0036] Furthermore, the calculation process of the interpolation processing is as follows:

[0037]

[0038]

[0039] In the above formula, h i 、v j 、h i+1 and v j+1 represents the coordinates of the adjacent feature points, α1 represents the ballistic elements on feature point 1, α2 represents the ballistic elements on feature point 2, α3 represents the ballistic elements on feature point 3, α4 represents the ballistic elements on feature point 4, and u represents h * to h i The normalized distance, w represents v * to v j The normalized distance. Represents the ballistic parameters obtained by interpolation from the parameter database.

[0040] The beneficial effects of the method of the present invention are as follows: the present invention establishes a boost phase motion model of a boost glide missile and designs a boost phase flight program to achieve different boost phase terminal states, thereby adapting to different mission requirements; and solves ballistic parameters through a constructed high-precision parameter database and an interpolation method, thereby solving the problems of slow solution speed of traditional ballistic parameter parameters and excessively long pre-launch preparation time; uses a neighboring point bilinear interpolation method to perform interpolation calculation on the ballistic parameters, and performs simulation calculation based on the parameters, so that the ballistic simulation flight has lower errors in height, speed and speed inclination. BRIEF DESCRIPTION OF THE DRAWINGS

[0041] Figure 1 This is a flowchart of the steps of a method for quickly calculating trajectory parameters based on a database of the present invention;

[0042] Figure 2 is a schematic diagram of an adaptive mesh generation method in a specific embodiment of the present invention;

[0043] Figure 3 This is a schematic diagram of a high-precision data base established for the boost phase of a boost-glide missile according to the present invention;

[0044] Figure 4 is a schematic diagram of the positional relationship between a target point and adjacent points in a specific embodiment of the present invention;

[0045] Figure 5 This is a schematic diagram explaining the method of equal-spaced grid division;

[0046] Figure 6 This is a schematic diagram explaining the inverse distance weighted interpolation algorithm. DETAILED DESCRIPTION

[0047] The present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments. The step numbers in the following embodiments are provided for ease of description only and do not limit the order of the steps. The order of execution of the steps in the embodiments can be adaptively adjusted based on the understanding of those skilled in the art.

[0048] Reference Figure 1 The present invention provides a method for quickly calculating trajectory parameters based on a database, the method comprising the following steps:

[0049] S1. Construct a boost phase motion model for a boost-glide missile.

[0050] Specifically, taking a boost-glide missile as an example, a motion model of the boost phase of a boost-glide missile is established in a semi-velocity coordinate system. The motion model of the boost phase of the boost-glide missile is specifically as follows:

[0051]

[0052] In the above formula, V represents velocity, θ represents velocity inclination, σ represents track yaw angle, v represents roll angle, φ represents latitude, λ represents longitude, r represents distance from the center of the earth, α represents angle of attack, m represents mass, and P e represents thrust, and g represents gravitational acceleration.

[0053] S2. Based on the boost phase motion model, set the boost phase flight program and obtain the boost phase terminal state;

[0054] Specifically, according to different mission requirements, the boost phase flight program can be designed to achieve different boost phase terminal states. The boost phase terminal state includes the boost phase terminal altitude, speed, and speed inclination. The boost phase terminal state affects the total range of the missile. The flight program design is as follows:

[0055]

[0056] In the above formula, represents the flight program of a boost-glide missile, t 11 Indicates the end time of the vertical take-off phase of the boost-glide missile, t 12 Indicates the end time of the attack angle turning phase of the boost-glide missile, t 13 Indicates the end time of the gravity turning phase of the boost-glide missile, t 1s Indicates the end time of the fixed-axis flight phase of the boost-glide missile, t 2s Indicates the end time of the secondary flight phase of the boost-glide missile, t 3s Indicates the end time of the third stage flight of the boost-glide missile. It represents the rate of change of the secondary constant pitch angle of the boost-glide missile. Indicates the three-level constant pitch angle change rate of the boost-glide missile;

[0057] In the angle of attack turning section, the expression of the angle of attack α(t) is:

[0058] α(t)=-α m sin 2 f(t)

[0059] Further,

[0060]

[0061] In the above formula, K is related to the time when the angle of attack reaches its extreme value, α m Indicates the extreme value of the angle of attack in the angle-of-attack turning section.

[0062] S3. Determine the trajectory data of the boost phase according to the boost phase terminal state and construct a data database;

[0063] Specifically, ballistic parameters are a set of parameters used to adjust the control instruments and aiming system before launch and to control the missile's motion state during flight. They mainly refer to the flight program, shutdown functional, and firing azimuth.

[0064] S31. Determine the parameters of the boost phase trajectory data according to the boost phase terminal state;

[0065] Specifically, in the design of the flight program, the end time of the vertical takeoff segment t is basically determined based on the characteristics of the aircraft and the laws of flight dynamics. 11 , the end time of the angle of attack turning section t 12 , the end time of the first-level flight segment t 1s , Secondary flight segment end time t 2s And the end time of the third-level flight segment t 3s If the trajectory parameters take into account the duration of the gravity turning segment and the duration of the fixed axis flight segment, a smaller time step is required in the trajectory integration process to ensure that the iterative increment is at the time step node, thereby achieving better accuracy. However, due to the small time step, the efficiency of the trajectory integration calculation is greatly reduced. Therefore, these two parameters can be determined according to the traditional flight dynamics method, that is, at the end time t 12 and the end time of the first-level flight segment t 1s The starting time of the fixed-axis flight segment is reasonably selected to ensure that the state of the aircraft at the shutdown point of the boost segment meets the boost segment terminal constraint. Specifically, on the one hand, the calculation efficiency of the standard trajectory parameters can be improved while ensuring the calculation accuracy; on the other hand, the dimension of the database parameters can be reduced. The trajectory parameters of the boost segment are selected as the extreme value α of the angle of attack turning segment. m And the second and third level constant pitch angle change rate and

[0066] S32. Determine the constraints of the boost phase terminal state under the maximum and minimum range conditions by direct method, and obtain the boundary ranges of the trajectory data parameters of the boost phase;

[0067] Specifically, refer to Figure 2 Once these three parameters are determined, the boost phase flight program and the terminal state of the boost phase of the aircraft can be obtained. Conversely, the trajectory parameters can also be solved based on the boost phase terminal state constraints. The boost phase terminal constraints are the height, speed, and speed angle constraints of the missile separation point, that is, h1 = h * 、v1=v * and θ1=θ * For boost-glide missiles, the terminal velocity inclination is generally 0. The direct method is used to determine the terminal constraint conditions (h max ,v max ) and (hmin ,v min ), which serves as the boundary of the metadata database.

[0068] S33, based on the boundary range of the trajectory data parameters of the boost phase, performing a meshing process on the boost phase terminal state using an adaptive meshing method to obtain mesh feature points;

[0069] Specifically, refer to Figure 3 To improve the computational efficiency of database establishment and overcome the errors caused by equally spaced grid partitioning at the boundary, an adaptive grid partitioning method will be used for the height and speed of the aircraft shutdown point within the terminal constraints of the boost phase to obtain a number of height-speed grid feature points. An equally spaced grid partitioning method will be used in the two-dimensional space of the terminal velocity and terminal altitude of the boost phase to obtain grid feature points. Then, at each feature point, the ballistic parameters that meet the terminal constraints are calculated, and the gradient changes of the ballistic parameters with respect to the terminal velocity and terminal altitude are analyzed. In the area where the gradient changes of the parameter parameters are high, the grid feature points will be encrypted; while in the area where the gradient changes of the parameter parameters are low, the grid feature points will remain relatively sparse.

[0070] Furthermore, the adaptive grid generation method can be replaced by an equally spaced grid generation method, and the interpolation method can be replaced by neural network fitting, polynomial fitting, and inverse distance weighted interpolation methods. The specific replacement methods are as follows:

[0071] Equally spaced meshing:

[0072] Reference Figure 5 In the selection of feature points, the idea of ​​equidistant grid division can be adopted, that is, within a certain range, the height and speed of the shutdown point are increased at the same interval respectively, and then the grid feature points are determined. This method can quickly mark the grid feature points in the database, so it has the advantages of short time consumption and convenient operation. However, it is difficult to select a suitable division distance for equidistant grid division. If the division interval is too large, the accuracy of the database-based element solution method will be poor. If the grid division interval is too small, the speed of database establishment will be reduced.

[0073] Inverse distance weighted interpolation:

[0074] Reference Figure 6 Since the elements of feature points closer to the target point are closer to the elements to be solved than those of feature points farther away, when solving the ballistic elements of the target position, the inverse distance weighted interpolation method will make predictions based on the four nearest feature points, and the feature points closer to the target position are assigned larger weights, while the feature points farther away are assigned smaller weights;

[0075] That is, given a target location for a mission, the four closest feature points can be selected from the trajectory library by sorting by distance. Based on the longitude and latitude of the target point and the adjacent points, combined with spherical trigonometry theory, the distances R1, R2, R3, and R4 between the target point and the four adjacent points can be obtained.

[0076] Therefore, according to the inverse distance weighted interpolation method, the weight function of each adjacent corresponding value is:

[0077]

[0078] In the above formula, p represents the weight parameter, and p∈[-3,0]. The closer p is to zero, the greater the influence of feature points farther away on the predicted value.

[0079] Therefore, the predicted values ​​of the target impact point for:

[0080]

[0081] In the above formula, w i Represents the weight coefficient of the adjacent feature points, α i Represents the ballistic elements near the feature point;

[0082] S34. According to the terminal state of the boosting segment at the grid feature point, the various parameters at the grid feature point are iteratively calculated using the Newton iteration algorithm, the calculation results are output, and a database of various parameters is constructed.

[0083] Specifically, the boost phase terminal state in step S31 is the boundary of the database, that is, the boost phase terminal state under the maximum range and minimum range conditions, respectively. The characteristic points on the database are divided by the boost phase terminal state (terminal height and speed), so the boost phase terminal state in step S34 is the terminal state at the database characteristic point. Finally, when using database interpolation, the target parameters are obtained by interpolation calculation based on the boost phase terminal state of the mission target. The accuracy of the database-based parameter solution method is related to the number of characteristic points. The more characteristic points there are, the larger the database scale, the higher the solution accuracy, and the longer the database construction time; at each characteristic point, the Newton iteration method is used to solve the three boost phase trajectory parameters that meet the terminal constraint conditions, and the parameter α of each group of parameters is recorded. m 、 and Form a complete high-precision database.

[0084] S341. According to the actual accuracy requirements of the launch mission, set the accuracy threshold corresponding to each parameter;

[0085] Specifically, the terminal constraints of the boost phase include the terminal height h * , terminal velocity v * and the local velocity inclination angle θ *, then the trajectory parameters α m 、 and The determination steps are as follows: first, let the iteration control variable k = 0, and give the initial value α m 、 and Set the iterative calculation control accuracy ε1, ε2 and ε3.

[0086] S342. Integrate and calculate the boost phase trajectory of the boost-glide missile to obtain the initial boost phase terminal state;

[0087] S343, performing subtraction processing on the constraint condition of the boost phase terminal state and the initial boost phase terminal state to obtain a difference value;

[0088] Specifically, the boost phase trajectory is integrated and the boost phase terminal state h is obtained. k , v k and θ k , determine whether the following relationship exists. If so, directly output the calculation result. If not, loop through steps S344 and S345 until the calculation result satisfies the following relationship:

[0089]

[0090] S344, judging the difference, judging that the difference is greater than a preset accuracy threshold, and constructing a Jacobian matrix based on the difference;

[0091] Specifically, and As parameters, calculate the terminal parameters and by and As parameters, the terminal parameters are calculated and by and + is the parameter, and the terminal parameters are calculated and Use the difference method to get the Jacobian matrix M k , the Newton calculation formula is as follows:

[0092]

[0093] In the above formula, M k The Jacobian matrix of the boosting segment terminal parameters, α m 、 and Represents the parameters of the trajectory elements, h represents the height constraint in the constraints of the terminal state of the boost phase, v represents the velocity constraint in the constraints of the terminal state of the boost phase, θ represents the local velocity inclination constraint in the constraints of the terminal state of the boost phase, In the Newton iteration method, h represents the terminal height of the boosting segment obtained by adjusting the integral of the iteration amount; k represents the terminal height of the boosting segment obtained by substituting the initial value of the iteration into the integral, In the Newton iteration method, the terminal velocity of the boosting segment is obtained by adjusting the integral of the iteration amount, v k represents the terminal velocity of the boosting stage obtained by substituting the initial value of the iteration into the integral, In the Newton iteration method, the terminal velocity inclination angle of the boosting segment is obtained by adjusting the integral of the iteration amount, θ k It represents the terminal velocity inclination angle of the boosting phase obtained by substituting the initial value of the iteration into the integral, and δ represents a small amount.

[0094] S345. Iteratively calculate the Jacobian matrix using the Newton iteration formula until the calculation result is less than a preset accuracy threshold, output the calculation result and construct a database of various elements.

[0095] Specifically, the Newton iteration formula is as follows:

[0096]

[0097] In the above formula, Indicates the maximum negative angle of attack of the trajectory elements in the previous iteration, Indicates the maximum negative angle of attack of the trajectory elements under the current iteration number, Indicates the rate of change of the trajectory parameters secondary program angle of the previous iteration, Indicates the rate of change of the secondary program angle of the trajectory parameters under the current iteration number, Indicates the rate of change of the trajectory parameters three-level program angle in the previous iteration, Indicates the rate of change of the trajectory parameters three-level program angle under the current iteration step, h * The terminal height of the boost phase of the target, v * represents the terminal velocity of the target during the boost phase, θ * Indicates the target's boost phase terminal velocity inclination angle;

[0098] The present invention takes into account the differences in the impact of different launch point and target point positions on the trajectory parameters of the boost phase. In order to improve the adaptability of the parameter database to the mobile launch environment, the terminal height and terminal velocity of the boost phase are used as indicators when establishing the parameter database, thereby obtaining a three-dimensional database of trajectory parameters regarding height and velocity, namely, the parameter database.

[0099] S4. Based on the various metadata database, the boost phase trajectory data of the boost glide missile is obtained by interpolating the four feature points adjacent to the boost phase terminal state of the target.

[0100] S41. Setting the distance between the starting point and the target point of the missile, and determining the terminal parameters of the missile using a range analytical formula, wherein the terminal parameters of the missile include the terminal altitude and speed of the target in the boost phase;

[0101] S42, searching and processing the terminal parameters of the missile based on the various element databases to obtain adjacent feature points;

[0102] S43. Perform interpolation processing on adjacent feature points to obtain the boost phase trajectory data of the boost-glide missile.

[0103] Specifically, refer to Figure 4 For a given launch mission, based on the distance between the starting point and the target point, the terminal altitude and speed of the boost phase target can be determined by the range analytical formula: Find four feature points close to it in the metadata database, which are (h i ,v j )、(h i+1 ,v j )、(h i ,v j+1 ) and (h i+1 ,v j+1 );

[0104] The voyage analysis formula is specifically as follows:

[0105] In the semi-velocity coordinate system, the ballistic motion equation of the gliding segment is established as follows:

[0106]

[0107] In the above formula, h represents the flight altitude, S represents the ballistic range, R e represents the radius of the Earth;

[0108] In the gliding phase, the aircraft flies at an altitude between the dense atmosphere and the rarefied atmosphere, and has ballistic characteristics such as the jump glide trajectory and the balanced glide trajectory. Next, based on the characteristics of the balanced glide trajectory, the range estimation problem of the gliding aircraft will be studied. Assuming that the velocity inclination angle is a small amount, that is, θ≈0, based on the quasi-balanced glide condition,

[0109] Therefore, we can get:

[0110]

[0111] Furthermore, the direct relationship between range and speed is derived as follows:

[0112]

[0113] Integrate to get the formula for the maximum gliding range:

[0114]

[0115] In the above formula, V0, h0 and V f They are respectively the terminal velocity of the boost phase, the terminal altitude and the terminal velocity of the glide phase;

[0116] The trajectory parameters corresponding to the terminal height and velocity of the boost phase target (h * ,v * ) can be obtained by interpolating the data of the nearby feature points in the database through the bilinear interpolation method of the nearby points, as shown below:

[0117]

[0118]

[0119] In the above formula, h i 、v j 、h i+1 and v j+1 represents the coordinates of the adjacent feature points, α1 represents the ballistic elements on feature point 1, α2 represents the ballistic elements on feature point 2, α3 represents the ballistic elements on feature point 3, α4 represents the ballistic elements on feature point 4, and u represents h * to h i The normalized distance, w represents v * to v j The normalized distance. Represents the trajectory parameters obtained by interpolation of the parameter database;

[0120] This solution specifically includes database construction and usage steps. Furthermore, taking the calculation of various ballistic elements of the boost-glide missile's boost phase trajectory as an example, in a simulation environment using an AMD Ryzen 5 4600H and 16.0GB of RAM, the traditional Newton iteration method takes 10.77 seconds to calculate, while the database-based element calculation method takes 0.0081 seconds, greatly improving computational efficiency. The results show that the height error of the boost-phase trajectory shutdown point is within 2 meters, and the absolute value of the velocity error is within 0.02 m / s.

[0121] The above is a specific description of the preferred implementation of the present invention, but the invention is not limited to the embodiments. Those skilled in the art can make various equivalent modifications or substitutions without violating the spirit of the present invention. These equivalent modifications or substitutions are all included in the scope defined by the claims of this application.

Claims

1. A method for quickly calculating trajectory parameters based on a database, characterized in that: The following steps are involved: Construct a boost phase motion model for a boost-glide missile; Based on the boost phase motion model, the boost phase flight program is set to obtain the boost phase terminal state; The terminal state of the boosting section is segmented by an adaptive grid segmentation method to obtain grid feature points. According to the grid feature points and the terminal state of the boost phase, the trajectory data of the boost phase are determined and a data database is constructed; Based on the element database, the four feature points adjacent to the boost phase terminal state are interpolated to obtain the boost phase trajectory elements of the boost glide missile. The boost phase motion model of the boost-glide missile is specifically constructed as follows: In the above formula, V represents velocity, θ represents velocity inclination, σ represents track yaw angle, v represents roll angle, φ represents latitude, λ represents longitude, r represents distance from the center of the earth, α represents angle of attack, m represents mass, and P e represents thrust, g represents gravitational acceleration; The step of obtaining the boost phase trajectory elements of the boost-glide missile by interpolating four feature points adjacent to the boost phase terminal state based on the element database specifically includes: Setting the distance between the missile's starting point and target point, and determining the missile's terminal parameters using a range analytical formula, the missile's terminal parameters include the terminal altitude and speed of the boost phase target; Based on the various metadata database, the terminal parameters of the missile are searched and processed to obtain adjacent feature points; Interpolation processing is performed on the adjacent feature points to obtain the ballistic parameters of the boost phase of the boost-glide missile.

2. The method for quickly calculating trajectory parameters based on a database according to claim 1, characterized in that: The flight procedures are as follows: In the above formula, represents the flight program of a boost-glide missile, t 11 Indicates the end time of the vertical take-off phase of the boost-glide missile, t 12 Indicates the end time of the attack angle turning phase of the boost-glide missile, t 13 Indicates the end time of the gravity turning phase of the boost-glide missile, t 1s Indicates the end time of the fixed-axis flight phase of the boost-glide missile, t 2s Indicates the end time of the secondary flight phase of the boost-glide missile, t 3s Indicates the end time of the third stage flight of the boost-glide missile. It represents the rate of change of the secondary constant pitch angle of the boost-glide missile. Indicates the three-level constant pitch angle change rate of the boost-glide missile.

3. The method for quickly calculating trajectory parameters based on a database according to claim 2, characterized in that: The step of determining the trajectory data of the boost phase based on the grid feature points and the boost phase terminal state and constructing a data database specifically includes: The constraints of the boost phase terminal state under the maximum and minimum range conditions are determined by direct method, and the boundary ranges of the boost phase trajectory data parameters are obtained. Based on the boundary range of the boost phase trajectory data parameters, the boost phase terminal state is segmented by an adaptive grid segmentation method to obtain grid feature points. According to the terminal state of the boosting segment on the grid feature point, the various parameters on the grid feature point are iteratively calculated using the Newton iteration algorithm, the calculation results are output and a database of various parameters is constructed.

4. The method for quickly calculating trajectory parameters based on a database according to claim 3, characterized in that: The step of iteratively calculating the various parameters on the grid feature points by using the Newton iterative algorithm, outputting the calculation results and constructing a database of various parameters specifically includes: According to the actual requirements of the launch mission, set the accuracy threshold corresponding to each parameter; Integrate the boost phase trajectory of the boost-glide missile to obtain the initial boost phase terminal state; Performing a difference process on the constraint condition of the boost phase terminal state and the initial boost phase terminal state to obtain a difference value; The difference is judged, and if it is greater than a preset accuracy threshold, a Jacobian matrix is ​​constructed based on the difference; The Jacobian matrix is ​​iteratively calculated using the Newton iteration formula until the calculation result is less than the preset accuracy threshold, the calculation result is output and a database of various elements is constructed.

5. The method for quickly calculating trajectory parameters based on a database according to claim 4, characterized in that: The Jacobian matrix is ​​specifically as follows: In the above formula, M k The Jacobian matrix of the boosting segment terminal parameters, α m 、 and Represents the parameters of the trajectory elements, h represents the height constraint in the constraints of the terminal state of the boost phase, v represents the velocity constraint in the constraints of the terminal state of the boost phase, θ represents the local velocity inclination constraint in the constraints of the terminal state of the boost phase, In the Newton iteration method, h represents the terminal height of the boosting segment obtained by adjusting the integral of the iteration amount; k represents the terminal height of the boosting segment obtained by substituting the initial value of the iteration into the integral, In the Newton iteration method, the terminal velocity of the boosting segment is obtained by adjusting the integral of the iteration amount, v k represents the terminal velocity of the boosting stage obtained by substituting the initial value of the iteration into the integral, In the Newton iteration method, the terminal velocity inclination angle of the boosting segment is obtained by adjusting the integral of the iteration amount, θ k It represents the terminal velocity inclination angle of the boosting phase obtained by substituting the initial value of the iteration into the integral, and δ represents a small amount.

6. The method for quickly calculating trajectory parameters based on a database according to claim 5, characterized in that: The Newton iteration calculation formula is as follows: In the above formula, Indicates the maximum negative angle of attack of the trajectory elements in the previous iteration, Indicates the maximum negative angle of attack of the trajectory elements under the current iteration number, Indicates the rate of change of the trajectory parameters secondary program angle of the previous iteration, Indicates the rate of change of the secondary program angle of the trajectory parameters under the current iteration number, Indicates the rate of change of the trajectory parameters three-level program angle in the previous iteration, Indicates the rate of change of the trajectory parameters three-level program angle under the current iteration number, h * The terminal height of the boost phase of the target, v * represents the terminal velocity of the target during the boost phase, θ * Indicates the target's terminal velocity inclination during the boost phase.

7. The method for quickly calculating trajectory parameters based on a database according to claim 6, characterized in that: The calculation process of the interpolation process is as follows: In the above formula, h i 、v j 、h i+1 and v j+1 represents the coordinates of the adjacent feature points, α1 represents the ballistic elements on feature point 1, α2 represents the ballistic elements on feature point 2, α3 represents the ballistic elements on feature point 3, α4 represents the ballistic elements on feature point 4, and u represents h * to h i The normalized distance, w represents v * to v j The normalized distance of Represents the ballistic parameters obtained by interpolation from the parameter database.

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