A method for correcting firing data of a closed-loop calibration system suitable for a satellite measurement point few working conditions

Abstract

This invention discloses a method for correcting firing parameters in a closed-loop firing correction system suitable for conditions with very few satellite measurement points. It adds a rotational speed measuring device to the projectile system to measure the real-time rotational speed of the artillery projectile. Based on external ballistics theory, this invention utilizes muzzle rotation speed, ballistic speed, and measurement data (coordinates and velocities) from a limited number of ballistic points to propose a method for estimating the range and lateral deviations of a single projectile relative to the target point. This allows for the rapid determination of the launch angle and directional corrections, enabling artillery firing correction. This invention solves the key problem of how to quickly and accurately determine the firing parameter corrections of a closed-loop firing correction system when there are very few ballistic measurement points, greatly improving the adaptability and reliability of the closed-loop firing correction system under complex battlefield conditions and effectively enhancing the combat capability of the weapon system.

Description

Technical Field

[0001] This invention belongs to the fields of external ballistics ballistic correction theory, artillery firing science, and artillery weapon system applications, and in particular, it is a method for correcting firing parameters of a closed-loop firing system suitable for conditions with very few satellite measuring points. Background Technology

[0002] This invention is based on a closed-loop firing correction system, which consists of two parts: an onboard system and a ground system. The onboard system includes a projectile rotation speed measuring device and a satellite positioning measuring device. The rotation speed measuring device (a mature technology) is powered on and operates while the projectile is moving inside the gun barrel, and can measure the muzzle rotation speed of each fired projectile. Furthermore, as the projectile flies, the projectile's rotational speed along its trajectory can be measured.

[0003] The satellite positioning and measurement device is used to receive satellite positioning signals in real time and transmit the signals to the ground system. The ground system receives the satellite positioning signals of the projectile in real time and transmits them to the computer for processing. The computer calculates the impact point of the projectile and then determines the firing data correction amount (including the angle correction amount and the direction correction amount) based on the deviation between the impact point and the target and transmits it to the fire control system, thereby adjusting the artillery firing data.

[0004] Based on the above description, one of the core foundations of this closed-loop firing correction system is missile-borne satellite positioning measurement. Under normal circumstances, satellite positioning can measure a relatively long flight trajectory (e.g., 30-40 seconds), resulting in a denser measurement point. This facilitates trajectory filtering and trajectory parameter state estimation. By substituting the filtered and estimated parameters into the trajectory equations and performing numerical integration, the impact point of the projectile can be predicted. By comparing this with the target coordinates, the firing parameter corrections can be accurately calculated.

[0005] However, actual battlefield conditions are quite complex. Especially with the development of advanced information technologies such as electronic warfare, satellite positioning and measurement are easily subject to various interferences on the battlefield. The number of measurement points and signal quality are severely affected. Under certain severe interference conditions, there may be very few satellite measurement points available; that is, after signal reception, signal transformation, data processing, and quality assessment, only 2-3 measurement points may be usable. In this situation, ballistic filtering and ballistic parameter state estimation cannot be performed normally. If forced to use them, abnormal results may be obtained. For example, one of the key objectives of ballistic parameter state estimation is to accurately estimate the actual drag coefficient of the projectile. Engineering practice shows that if the data conditions are insufficient (too few data points), the estimation results are difficult to converge, and the estimated drag coefficient will deviate significantly from the actual value, ultimately leading to large errors in impact point prediction and inaccurate calculation of firing data corrections.

[0006] Therefore, there is an urgent need for a ballistic technology that can effectively calculate the correction of firing parameters under conditions where there are very few satellite measurement points. This is also a necessary function for the closed-loop firing correction system to adapt to complex battlefield environments, but there is no relevant description in the existing technology. Summary of the Invention

[0007] When applied to ground artillery weapon systems, closed-loop firing correction systems based on satellite positioning measurements are susceptible to strong interference from complex battlefield environments, leading to significant data loss and a scarcity of effective measurement points. This severely impacts the determination of firing parameter corrections—a crucial step in the closed-loop firing correction process. Therefore, the purpose of this invention is to propose an appropriate method for determining firing parameter corrections under conditions with limited satellite measurement points, providing an effective solution to improve the adaptability of closed-loop firing correction systems to complex battlefield environments.

[0008] The technical solution to achieve the purpose of this invention is as follows:

[0009] A method for correcting firing parameters in a closed-loop firing system suitable for conditions with very few satellite measurement points includes the following steps:

[0010] Step 1: Determine the initial velocity deviation Δv0: Measure the muzzle rotation speed of the projectile and calculate the actual initial velocity of the projectile. Based on the table of initial velocities, calculate the initial velocity deviation Δv0.

[0011] Step 2: Determine the launch angle deviation Δθ0: Using the ballistic equation of the mass point and the ballistic data of the first effective measuring point, iteratively adjust the launch angle calculated from the ballistic calculation by comparing the calculated value and the measured value of the height at the effective point until the calculated value matches the measured value. Then estimate the actual launch angle θ0 and determine the launch angle θ according to the table. 0N Find the angle deviation Δθ0;

[0012] Step 3: Determine the drag coefficient deviation Δc x Using the velocity data from the first and last two effective measurement points of each segment, with the data from the first effective measurement point as the initial condition, the drag coefficient used for trajectory calculation is iteratively adjusted based on the difference between the calculated and measured velocity values ​​at the last effective measurement point until the calculated and measured velocity values ​​match. This yields the drag coefficient deviation for each segment. The average value is then taken to obtain the drag coefficient deviation Δc. x ;

[0013] Step 4: Determine the angle correction Δθ 0C Based on external ballistics theory, the angle correction Δθ is calculated. 0C ;

[0014] Step 5: Determine the projectile's deviation and its coincidence coefficient: Based on the derivatives of the lift coefficient and the static moment coefficient, combined with the projectile's extreme moment of inertia, length, and actual mass, estimate the deviation at the farthest effective trajectory measurement point; compare the actual deviation value at the farthest effective trajectory measurement point with the estimated deviation value to obtain the coincidence coefficient;

[0015] Step 6: Determine the direction correction Δψ0: Look up the firing table to obtain the range X listed in the table. TAB Then the range of the projectile is X = X TAB +ΔX, where ΔX is the difference between the range of the projectile and the target range; calculate the azimuth angle ψ0 of the trajectory deviating from the firing surface; consult the firing table to obtain the azimuth angle ψ. 0N Find the direction correction amount Δψ0.

[0016] The significant advantages of this invention compared to existing technologies are:

[0017] (1) Under conditions of extremely limited data and inability to effectively carry out normal processing procedures such as ballistic filtering and state estimation, this invention delves into external ballistic theory and makes full use of the limited data. The theoretical calculation model established by this invention is not a purely theoretical model, but a model that has been modified with necessary adjustments based on measured data, making it more consistent with reality.

[0018] (2) In the technical solution of the present invention, iterative calculation is used for simple models (such as the ballistic equation of a point mass), while single calculation is used for complex models (such as the ballistic equation of a rigid body), which effectively matches the model complexity and computational load, and ensures the speed and accuracy of the technology application.

[0019] (3) The technical solution of the present invention can be compiled into a corresponding computer program and installed into the ground system (fire control computer) of the closed-loop firing correction system to achieve fully automated processing. Attached Figure Description

[0020] Figure 1 A schematic diagram of effective satellite measurement points under complex battlefield environments and strong interference conditions.

[0021] Figure 2 This is a flowchart of the technical solution of the present invention. Detailed Implementation

[0022] The present invention will be further described below with reference to the accompanying drawings and specific embodiments.

[0023] For ground artillery weapon systems employing this firing correction system, the onboard rotational speed measurement is unaffected by satellite signal interference. However, in complex battlefield environments with strong interference, the onboard system's satellite signal receiver can only obtain a very limited number of measurement points. Assuming that after signal processing, quality assessment, and data processing, only three effective satellite measurement points are available, such as... Figure 1As shown in the figure. This embodiment uses three valid satellite measurement points as an example for illustration.

[0024] Due to the extremely limited number of effective satellite tracking points, ballistic filtering and trajectory prediction can no longer be performed normally. For each effective satellite tracking point, including the projectile at time t... i Position coordinates (x) i ,y i ,z i ) and velocity (v) xi ,v yi ,v zi ), i = 1, 2, 3 (representing 3 valid satellite measurement points). v xi ,v yi ,v zi Let be the velocity components along the X, Y, and Z axes of the i-th valid satellite measurement point.

[0025] The following is the angle correction Δθ based on external ballistics theory and limited measurement data. 0C Method for determining the direction correction amount Δψ0.

[0026] This embodiment provides a method for determining the correction parameters of a closed-loop firing system suitable for operating conditions with very few satellite measurement points, comprising the following steps:

[0027] Step 1: Determine the initial velocity deviation Δv0

[0028] The projectile's muzzle rotation speed γ0 can be measured by the onboard system's rotation speed measurement device. Based on external ballistics theory, the actual initial velocity of the projectile can be estimated relatively accurately using the following formula:

[0029]

[0030] In the formula: d is the projectile diameter; η is the artillery twist rate, which is a known value.

[0031] Since the propellant charge number is fixed when the artillery is fired, the initial velocity v is determined. 0N Given this, we can find Δv0 = v0 - v 0N .

[0032] Step 2: Determine the angle deviation Δθ0

[0033] Based on actual initial velocity, actual projectile weight, and actual weather conditions (provided by the artillery meteorological support system), the actual firing angle is estimated through iterative calculations using the ballistic equations and ballistic data from the first valid measuring point. The specific process is as follows:

[0034] Using the point mass ballistic equation (see Han Zipeng's "External Ballistics of Projectiles and Rockets"), the actual mass of the projectile is taken (calculated from Δm), and the actual initial velocity v0 and the defined launch angle θ are used. 0NAs initial conditions, calculate the trajectory up to the first valid measuring point, and compare the calculated height y1 with the measured height y1. If the difference between the calculated and measured values ​​is less than a first set value (e.g., less than 1 meter), then the actual firing angle is considered to be the nominal firing angle θ. 0N Otherwise, the trajectory calculation angle, θ, is adjusted based on the difference between the two (the difference between the calculated value y1 and the measured value y1). 0N +Δθ0, and recalculate the trajectory to the first valid measuring point using the adjusted launch angle, comparing the calculated altitude y1 with the measured altitude y1. This process is repeated until the iteration termination condition is met (i.e., less than the first set value). Practice shows that Δθ0 is generally obtained with relatively high accuracy after 2-3 iterations.

[0035] Step 3: Determine the drag coefficient deviation Δc x

[0036] Still based on actual projectile weight, actual weather conditions (provided by the artillery weather support system), and using the point mass ballistic equation as the calculation model, Figure 1 The effective satellite measurement point 1 shown is the starting point for trajectory calculation, i.e., the position coordinates (x1, y1, z1) and velocity (v). x1 ,v y1 ,v z1 The initial condition for the ballistic integral is given by the standard drag coefficient c. xN Perform ballistic calculations up to the second effective satellite measuring point. Compare the calculated projectile velocity v2 at the second effective satellite measuring point with the measured value. The calculated and measured values ​​are compared. If the difference is less than the second set value (e.g., less than 0.2 m / s), the actual drag coefficient is considered to be the standard drag coefficient. Otherwise, the drag coefficient used for trajectory calculation is adjusted based on the difference between the two (the difference between the calculated and measured velocity values), i.e., c. xN +Δc x The trajectory is recalculated to the first valid measuring point using the adjusted drag coefficient, and the calculated and actual values ​​of the velocity at the first valid measuring point are compared. This process is repeated until the iteration termination condition is met (i.e., less than the second set value). The drag coefficient deviation between measuring point 1 and measuring point 2 is then obtained and denoted as [Δc]. x ] 12 .

[0037] Following the same approach described above, iterative calculations are performed based on the measured data from effective satellite measuring points 2 and 3 to obtain the drag coefficient deviation between measuring points 2 and 3, denoted as [Δc]. x ] 23 .

[0038] Considering the average effect on the trajectory, the drag coefficient deviation Δc x The average value above can be taken, that is

[0039]

[0040] If there are only two valid satellite measurement points, then Δc x =[Δc x ] 12 If there are four valid satellite measurement points, the deviation of the three drag coefficients obtained by iteration can be averaged. If there are more than four valid measurement points, but still not enough to carry out normal processing, then 3 to 4 measurement points can be selected for the above processing.

[0041] Step 4: Determine the angle correction Δθ 0C

[0042] Angle correction Δθ 0C It can be determined by the following formula

[0043]

[0044] In the formula: ΔX is the difference between the range of the projectile (i.e., distance) and the target range, and is a quantity to be determined; ΔX C The distance change corresponding to a one-unit change in the angle of incidence, as listed in the projection table, can be directly obtained from the table. Therefore, to calculate Δθ... 0C This is equivalent to finding ΔX.

[0045] According to external ballistics theory, ΔX can be composed of four parts, namely

[0046]

[0047] Where: Δv0, Δθ0, Δc x Δm represents the actual initial velocity v0 of the projectile relative to the stated initial velocity v0. 0N The deviation, the actual angle of incidence θ0 relative to the nominal angle of incidence θ 0N Deviation, actual drag coefficient c x Relative to the standard drag coefficient c xN The deviation, the deviation of the actual mass of the projectile from the mass of the standard projectile; These are the sensitivity factors of range to initial velocity, range to firing angle, range to drag coefficient, and range to projectile mass, respectively. These sensitivity factors can be obtained in advance and are known values.

[0048] From the above equation, we can see that finding ΔX is equivalent to finding Δv0, Δθ0, and Δc. x Δm, where the projectile mass deviation Δm can be directly determined from the projectile weight symbol marked on the projectile body. Therefore, finding ΔX mainly involves finding Δv0, Δθ0, and Δc. x .

[0049] From steps 1, 2, and 3 above, the values ​​of Δv0, Δθ0, and Δc for each shot are... xΔm can be obtained, and Since all values ​​are known, ΔX can be calculated using formula (4), and then obtained from the projection table. C The exit angle correction Δθ can be determined according to formula (3). 0C .

[0050] Step 5: Determine the projectile deviation and its coefficient of conformity.

[0051] Artillery shells are spin-stabilized projectiles, and their lateral deviation is mainly caused by the deflection flow. The formation of the deflection flow z is a cumulative effect on the trajectory and can be estimated using external ballistics theory. One commonly used estimation formula is...

[0052]

[0053] Where: x0, x f Let θ0 and θ' be the initial and final values ​​of the range X, respectively; f Let A and C be the initial and final values ​​of the trajectory inclination angle θ, respectively; and let C be the equatorial moment of inertia and polar moment of inertia of the projectile, respectively, which are known values. The rotational speed on the trajectory; v x b is the velocity component in the direction of the range. y =ρSc′ y / (2m), k z =ρSlm′ z / (2A), where ρ is the atmospheric density, S is the characteristic area of ​​the projectile (usually taken as the maximum cross-sectional area of ​​the projectile), l is the characteristic length of the projectile (usually taken as the projectile length), c′ y ,m′ z These are the derivatives of the lift coefficient and the static moment coefficient of the projectile, respectively, which are functions of the Mach number in the flight trajectory.

[0054] The lower limit of integration is set as: x0 = 0, θ0 = θ 0N +Δθ0 (i.e., the muzzle point); the upper limit of integration is taken as: x f =x3, θ f =arctan(v y3 / v x3 (i.e., effective satellite measuring point 3, which is also the farthest ballistic measuring point). The velocity in the range direction is taken as the average value. Aerodynamic coefficient c′ y ,m′ z The value is determined by the average Mach number between the muzzle point and measuring point 3, i.e. S and l are known values, m is the actual mass of the projectile (still determined directly by the projectile weight sign), and the rotational speed is... Take the average measurement value between the muzzle point and measuring point 3. Expanding the integral formula (5), we can obtain the formula for estimating the flow deviation at the three measuring points:

[0055]

[0056] Compare the actual deviation value z3 at measuring point 3 with the calculated value By comparison, the coefficient of agreement β of formula (6) can be obtained. z ,Right now

[0057]

[0058] Coefficient of conformity β z This reflects the deviation between the theoretical model and the actual situation. In the above technical solution, the purpose of selecting the farthest ballistic point is to improve the estimation accuracy of the deviation, because the farther the distance, the more fully the deviation accumulates and develops, and the higher the estimation accuracy.

[0059] Step 6: Determine the direction correction amount Δψ0

[0060] Since the estimation formula (5) is derived based on the rigid body ballistic equation (see Han Zipeng's "External Ballistics of Projectiles and Rockets"), the actual initial velocity, actual projectile weight, actual weather conditions (provided by the artillery weather support system), and actual drag coefficient are substituted into the rigid body ballistic equation to perform a ballistic calculation, and the calculated value of the impact point deviation (which is the value calculated by formula (6)) is used. Multiply by the conformity coefficient β z Then, the projectile's deflection estimate Z is obtained. Looking up the firing table, the range X can be obtained. TAB Furthermore, based on the previously determined ΔX, the estimated range of this projectile is X = X. TAB +ΔX, then the azimuth angle ψ0 of the ballistic deviation from the firing surface is

[0061]

[0062] A direction angle, denoted as ψ, can be determined based on the deflection value and direction correction amount listed in the injection table. 0N The direction correction amount can be determined by the following formula, i.e.

[0063] Δψ0=ψ0-ψ 0N (9)

[0064] Based on the above method for determining firing data corrections, the fire control servo system is automatically adjusted to the correct position via a computer program. The specific process is as follows: (See the flowchart below for the technical solution of this invention). Figure 2 This will be used to explain the specific implementation method.

[0065] Step 1: The artillery fires a shell. The rotational speed measuring device is activated and operates under the overload impact inside the barrel to measure the rotational speed of the shell. The muzzle speed of the projectile is measured when it leaves the muzzle. The initial velocity is determined according to formula (1) and by referring to the firing table, and the initial velocity deviation Δv0 is calculated.

[0066] Step 2: After the satellite positioning signal receiver exits the muzzle, the missile-borne system sends the received satellite positioning data from a segment of the trajectory back to the ground system. The ground system performs signal and data processing to determine whether it is an extreme condition (very few effective measuring points). If not, it proceeds to the normal data processing and trajectory calculation process; if it is determined to be an extreme condition with very few effective measuring points, it proceeds to the next step.

[0067] Step 3: Using the actual initial velocity (statistical initial velocity + initial velocity deviation), actual projectile weight (calculated as Δm according to the projectile weight symbol marked on the projectile), and actual weather conditions (provided by the artillery weather support system), the ballistic equation of mass and the ballistic data (position and velocity coordinates) of the first effective measuring point are used. The calculated firing angle is iteratively adjusted according to the difference between the calculated and measured values ​​of the height at the effective point until the calculated value matches the measured value. Then, the actual firing angle θ0 is estimated, and the statistical firing angle θ is found from the firing table. 0N Then the angle deviation is Δθ0=θ0-θ 0N .

[0068] Step 4: Using the actual initial velocity (statistical initial velocity + initial velocity deviation), actual projectile weight (calculated according to the projectile weight symbol marked on the projectile body), actual weather conditions (provided by the artillery weather support system), and actual firing angle, divide the projectile into segments according to effective measuring points. Using the velocity data (position and velocity coordinates) from the first and last effective measuring points of each segment, taking the data from the first effective measuring point as the initial condition, iteratively adjust the drag coefficient used for trajectory calculation by comparing the calculated velocity value with the measured value at the last effective measuring point until the calculated velocity value matches the measured value. This yields the drag coefficient deviation for each segment (relative to the standard drag coefficient of this type of projectile). Taking the average value gives the drag coefficient deviation Δc. x .

[0069] Step 5: Look up the sensitivity table to obtain the sensitivity factors. And the distance change ΔX corresponding to a change of 1 unit in the angle of incidence. C ΔX is calculated according to formula (4), and the angle correction Δθ is calculated according to formula (3). 0C .

[0070] Step 6: Using the data (time, position, velocity, and rotational speed) from the furthest effective trajectory measurement point, calculate the trajectory inclination angle θ at that point. f Average rotational speed from the muzzle to that point Calculate the average Mach number based on the muzzle velocity and the velocity at that point, and then find the derivative of the lift coefficient c′ from the projectile aerodynamic coefficient table using the average Mach number. y and the derivative of the static moment coefficient Based on the known extreme moment of inertia, length, and actual mass of the projectile, the deflection is estimated according to formula (6).

[0071] Step 7: Using the estimated deviation and the measured deviation at the farthest effective trajectory measurement point, calculate the coincidence coefficient β according to formula (7). z .

[0072] Step 8: Starting from the muzzle, substitute the actual initial velocity, actual projectile weight, actual weather conditions (provided by the artillery weather support system), and actual drag coefficient into the rigid body ballistic equation to calculate the trajectory to the point of impact, obtain the deflection calculation value, and multiply it by the coincidence coefficient β. z This gives the deviation value of the projectile.

[0073] Step 9: Look up the firing table to obtain the firing range X. TAB Then the range of the projectile is X = X TAB +ΔX, then calculate the direction angle ψ0 of the ballistic deviation from the firing surface according to formula (8); look up the firing table to obtain the table-determined azimuth angle ψ 0N Then, the direction correction Δψ0 can be calculated according to formula (9).

[0074] It is worth noting that the firing table data itself is stored in the computer of the ground system, and the table lookup in the above steps can be performed automatically; the above iterations and calculations are all completed automatically by the program in the computer; the determined firing angle correction and direction correction are used by the fire control servo system to adjust the gun to position and carry out more accurate firing of the next shell.

Claims

1. A method for correcting firing data of a closed-loop calibration system suitable for satellite measurement point few working conditions, characterized in that, The method comprises the following steps: Step 1, determining the muzzle velocity deviation Δv0: measuring the muzzle rotating speed of the projectile, calculating the actual muzzle velocity of the projectile, and determining the muzzle velocity deviation Δv0 according to the table muzzle velocity; Step 2, determining the angle deviation Δθ0: using the particle trajectory equation and the trajectory data of the first effective measuring point, adjusting the trajectory calculation angle according to the ratio difference between the calculated value and the measured value of the height at the effective point, until the calculated value and the measured value are consistent, then the actual firing angle θ0 is estimated, and the firing angle deviation Δθ0 is calculated according to the table 0N . Step 3, determining the drag coefficient deviation Δc x : Using the speed data of the first and last two effective measuring points of each section, taking the speed data of the first effective measuring point as the initial condition, adjusting the drag coefficient for trajectory calculation according to the difference between the calculated value and the measured value of the speed at the last effective measuring point until the calculated value and the measured value of the speed are consistent, then the drag coefficient deviation of each section is obtained, and the average value is taken to obtain the drag coefficient deviation Δc x ; Step 4, determining the angle of departure correction Δθ 0C : According to the exterior ballistic theory, the angle of departure correction Δθ 0C ; Angle of Elevation Correction Δθ 0C is determined by the equation: where ΔX is the difference between the projectile range and the target range, ΔX C is the distance change corresponding to a change of one unit in the listed firing angle in the firing table, Δv0, Δθ0, Δc x , Δm are the deviations of the actual initial velocity v0 of the projectile relative to the standard initial velocity v 0N , the deviation of the actual firing angle θ0 relative to the standard firing angle θ 0N , the deviation of the actual drag coefficient c x relative to the standard drag coefficient c xN , and the deviation of the actual mass of the projectile relative to the standard mass of the projectile, respectively; are the sensitivity factors of the range to the initial velocity, the range to the firing angle, the range to the drag coefficient, and the range to the mass of the projectile, respectively. Step 5, determining the deflection of the projectile and the coincidence coefficient: according to the lift coefficient derivative and the static moment coefficient derivative, combining the maximum moment of inertia of the projectile, the projectile length and the actual mass, the deflection of the farthest effective trajectory measuring point is estimated; the actual deflection value of the farthest effective trajectory measuring point is compared with the estimated deflection value to obtain the coincidence coefficient; Step 6, determine the direction correction Δψ0: look up the table to get the table load range X TAB , the range of the projectile is X=X TAB +ΔX, ΔX is the difference between the range of the projectile and the target range; the estimated flow is calculated by the arctangent function of the divisor of the range of the trajectory deviating from the shooting surface direction angle ψ0; look up the table, and get the table direction angle ψ 0N , find out the direction correction Δψ0.

2. The method according to claim 1, characterized in that, The actual muzzle velocity of the projectile is: wherein is the muzzle velocity of the projectile, d is the projectile diameter; and η is the gun spin.

3. The method of claim 1, wherein the method is characterized by: When determining the firing angle deviation, the actual muzzle velocity and the table muzzle angle are used as initial conditions to calculate the trajectory to the first effective measuring point, and the calculated value and the measured value of the height are compared; if the difference between the calculated value and the measured value is less than a set value, it is considered that the actual firing angle is the table firing angle, otherwise the firing angle of the trajectory calculation is adjusted according to the difference between the two values, and the trajectory is calculated again to the first effective measuring point, and then compared again until the iteration end condition is met.

4. The method of claim 1, wherein the method is characterized by: When determining the drag coefficient deviation, the calculated value and the measured value of the projectile speed of each effective satellite measuring point are compared; if the difference between the calculated value and the measured value is less than a second set value, it is considered that the actual drag coefficient is the standard drag coefficient, otherwise the drag coefficient used for trajectory calculation is adjusted according to the difference between the two values.

5. The method of claim 1, wherein the method is further characterized by: The deflection estimation formula is: wherein is the estimated value of the drift of the farthest effective trajectory measuring point, C is the polar moment of inertia of the projectile, m is the actual mass of the projectile, l is the characteristic length of the projectile, c' y , z are the lift coefficient derivative and the static moment coefficient derivative of the projectile, respectively, is the average measurement from the muzzle point to the farthest effective trajectory measuring point, θ0, θ f are the initial value and the terminal value of the trajectory inclination angle θ, respectively, t n is the time of the farthest effective trajectory measuring point.

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