A method for determining the density and jump angle accuracy of a projectile system

Abstract

A method for determining the density and jump angle accuracy of a projectile system, wherein a standard projectile is used to project a special composite projectile; the following data are measured accordingly: chamber pressure, firing angle, initial velocity, meteorological conditions, drag coefficient of component one (1), range, ground density, jump angle, intermediate error of jump angle, target density, and flight time; if the drag coefficients of enough components one (1) have been measured, the corresponding standard drag coefficient can be defined according to the measured data; after the launch, the coordinates of the impact points of component one (1) and component two (2) are measured and their density and jump angle accuracy are calculated accordingly, and the density and jump angle accuracy of the projectile or projectile in the projectile system are determined. The present invention greatly improves the shooting accuracy of the shooting table. It will definitely have a pioneering and important significance in the relevant technical field and the extended engineering application field.

Description

Technical Field

[0001] The invention relates to the field of exterior ballistic test design and application technology of a standard projectile and a novel composite projectile, and in particular provides a method for determining the density and jump angle accuracy of a projectile system. Background Art

[0002] Exterior ballistics is the science that studies the motion laws of standard projectiles (projectiles) in air flight and issues related to this motion. Exterior ballistics plays an important role in the design of standard projectiles (cannons) and ammunition, and is the theoretical basis for ensuring weapon accuracy and compiling firing tables. In 1954, Professor Zhang Shuzu translated Professor Fantchaili's "Exterior Ballistics". In 1956, Lecturer Pufa published my country's first exterior ballistics book "Exterior Ballistics". In 1960, my country's first exterior ballistics major was established. Since then, many exterior ballistics books have been published in China. Only in the [Reference 5] of the present invention's literature list, pages 632-634, 59 exterior ballistics books are listed.

[0003] The reference numbers and detailed information of each document cited in this invention are listed as follows:

[0004] [Document 1] Tan Lebin, ed. Introduction to Artillery. Beijing: Beijing Institute of Technology Press, 2014.2. (Modern Weapon Firepower System Series).

[0005] [Document 2] Yin Jianping, Wang Zhijun (chief editor). Ammunition Science. Beijing: Beijing Institute of Technology Press. 2014.2 (Modern Weapon Firepower System Series).

[0006] [Document 3] Wang Zeshan, He Weidong, Xu Fuming (eds.). Principles and Technology of Artillery Propellant Charge Design. Beijing: Beijing Institute of Technology Press. 2014.2. (Modern Weapon Firepower System Series).

[0007] [Document 4] Qian Linfang, ed. Artillery Ballistics. Beijing: Beijing Institute of Technology Press. 2016.6.

[0008] [Document 5] Han Zipeng et al., eds. Projectile and Arrow Exterior Ballistics. Beijing: Beijing Institute of Technology Press, 2014.2 (Modern Weapon Firepower System Series).

[0009] [Document 6] Zhao Chengji. Experimental analysis of problems in traditional jump angle measurement methods. Journal of Ordnance. 1985.04.

[0010] [Document 7] Beijing: National Defense Industry Press. 2002.1. National Defense Scientific Research and Experimental Engineering Technology Series Textbooks. Conventional Weapon Test System. ISBN 7-118-02732-4.

[0011] The function of a standard projectile is to give a standard projectile an initial velocity and an angle of fire. The standard projectiles launched by modern standard projectiles are mostly oblong rigid bodies. Most projectiles are oblong rigid bodies. When the projectile moves in the air, the geometric axis of the projectile does not coincide with the velocity vector line. The angle between the geometric axis of the oblong rigid body projectile and its flight speed direction is called the angle of attack for a tail-wing projectile and the nutation angle for a rotating projectile.

[0012] In order to ensure the flight stability of the oblong rigid projectile in the medium, [Reference 4] Artillery Ballistics P32 (P32 here means page 32, and the following text is abbreviated in this format) paragraph 3 points out: "The main methods for achieving projectile flight stability are tail fin stabilization and rotation stabilization." [Reference 5] P25-26 further elaborates on this and explains that " Figure 2 .1.1 Two ways of stabilization” force diagram. To ensure the stability of the projectile flight, there are two common methods: make the projectile rotate at high speed like a gyroscope, or install a tail fin on the projectile. For example, the last paragraph of [Reference 4] Artillery Ballistics P32 states: "The projectile head always points forward during flight, and the angle between the projectile axis and the trajectory tangent (nutation angle δ) is always less than a certain limit value along the entire trajectory. Such a projectile is generally referred to as a projectile with good flight stability."

[0013] The standard ejection device that ensures the stable rotation and flight of the projectile is a rifled standard ejection device with a rifled barrel, and the standard ejection device that achieves tail-stabilized flight is a smoothbore standard ejection device with a smoothbore barrel.

[0014] As we all know, the structure of standard projectiles must ensure the flight stability of standard projectiles in the medium. In order to increase the power of standard projectiles and enhance the killing effect of standard projectiles, modern standard projectiles use rifled standard projectiles or smoothbore standard projectiles to launch oblong standard projectiles. It is required that the head of the standard projectile always faces forward throughout the entire trajectory without turning over. This requires that when the standard projectile is disturbed by the outside world during flight, it is hoped that the standard projectile itself will be able to recover to the expected state of motion after the interference is removed.

[0015] In physical terms, the necessary condition for ensuring the flight stability of standard projectiles is the angle between the direction of the missile axis from the tail to the top of the missile and the velocity vector of the center of mass of the standard projectile (that is, the angle of attack δ for tail-mounted standard projectiles and the nutation angle for rotating standard projectiles). Even if it cannot be zero, it must vary within a sufficiently small range.

[0016] However, the oblong standard projectile will inevitably flip over during the flight. To ensure flight stability, there are currently two methods to ensure the stable flight of the standard projectile: one is to make the standard projectile rotate at high speed around the longitudinal axis of the standard projectile, the other is to install a tail fin on the standard projectile, or to use both the rotation method and the tail fin method on the same standard projectile to solve the stability problem.

[0017] Since the oblong standard projectile always has an angle of attack δ when flying in the air, this changes the pressure distribution of the air around the standard projectile, so that the pressure center P is between the top of the oblong standard projectile and the center of mass, and the resultant force R of the air on the oblong standard projectile produces an unstable turning moment M relative to the center of mass. How to ensure that the angle of attack δ of the oblong standard projectile changes within a very small range from beginning to end during the flight is the main problem to be solved in flight stability. However, the oblong standard projectile is almost bound to turn over during the flight. In order to ensure flight stability, there are two methods to make the standard projectile fly stably: one is to make the standard projectile rotate at high speed around the longitudinal axis of the standard projectile, and the other is to install a tail on the standard projectile, or to use both the rotation method and the tail method on the same standard projectile to solve the stability problem. The former is to rotate the standard projectile around the axis at high speed, so that it spins like a gyroscope without tipping over; the latter is to add a tail to the tail of the standard projectile to form a stable moment to resist turning over.

[0018] At present, the standard projectiles thrown from the standard projectiles are all oblong bodies of revolution, and they are usually regarded as rigid bodies. The trajectory of the standard projectile consists of two parts: the center of mass motion of the standard projectile and the motion of its axis around the center of mass. Since there is an angle of attack when the standard projectile performs rigid body motion, [Reference 5] P153-154 gives a 6-degree-of-freedom rigid body motion equation set for all forces and torques acting on the projectile. This equation set also gives the center of mass motion of the standard projectile rigid body and the motion of the axis of the standard projectile around the center of mass.

[0019] [Reference 1] Section 5.4.3 P42-43 points out that under the basic assumption of external ballistics with an angle of attack of zero, the trajectory of the projectile's center of mass will be a plane curve. It is uniquely determined by the initial velocity, the firing angle, and the ballistic coefficient. [Reference 1] P43 Figure 5 -9 gives a diagram of the relationship between the ballistic coefficient and the range after the initial velocity and the firing angle are determined. It can be seen from the diagram that the ballistic coefficient determines the range. [Reference 1] P44, paragraph 2 states: "The projectile moves around the center of mass while moving around the center of mass." Figure 5-1 0 gives a schematic diagram of spiral trajectory, deflection and dispersion; the overview of 6.1 on P47 gives "Figure 6-1 Schematic diagram of the outer contour of the gun barrel and the shell after they are chambered". [Reference 5] P138-342 Chapter 6-13 has a detailed analysis and description of this.

[0020] If the geometric axis of the oblong standard projectile is always consistent with the direction of the flight speed during its flight, that is, the nutation angle (or angle of attack) is zero, then the motion trajectory of the projectile's center of mass can be described by the three-degree-of-freedom differential equation of motion of the projectile's center of mass.

[0021] Under basic assumptions, the projectile can be simplified as a point mass, and the trajectory of the projectile's center of mass can be uniquely determined by the differential equations of the projectile's center of mass motion. [Reference 4] P21-22 gives the differential equations of the projectile's center of mass motion starting from the third paragraph.

[0022] [Reference 4] P13 formula (1-43) converts the air resistance acceleration a X Simplified to a x =CH(y)F(v)=CH(y)vG(v). "The air resistance acceleration is expressed as the product of the ballistic coefficient C representing the characteristics of the projectile, the density function H(y) representing the characteristics of the air, and the resistance function F(v) representing the influence of the projectile's motion relative to the air velocity." [Reference 4] P12 Formula (1-38) gives the expression of the ballistic coefficient C C=id 2 ×10 3 / m, where i is given in equation (1-33) on page 11 of [Reference 4]: i = C X0 (M a1 ) / C X0N (M a1 )=const. From the formula (1-34) in [Reference 4], it can be seen that the shape coefficient is mainly related to the length of the projectile head. The longer the head, the smaller the shape coefficient, that is, the smaller the air resistance. X0N (M a1 ) is the drag coefficient of the standard projectile. The drag coefficient of the standard projectile whose warhead length is 1.2-1.5 times the diameter of the projectile is called the Siache air resistance law, and the drag coefficient of the standard projectile whose warhead length is 3-3.5 times the diameter of the projectile is called the 43-year air resistance law.

[0023] [Reference 5]P39 Figure 2 .3.3 gives the "43-year drag law and Siache drag law curves". From this figure, we can further see that the shorter the projectile head, the greater the drag coefficient, and the difference between the two is about twice. [Reference 5] P35, paragraph 2 gives the head drag coefficient of the blunt body Figure 2 .2.13, it can be seen from the figure that the drag coefficient of the flat head is much larger than that of the hemispherical head. If the spherical projectile (i.e. component 1) is used as the standard projectile, the drag coefficient of the standard projectile is C X0N (M a1 )), then the shape coefficient i of the spherical projectile is equal to 1. From this we can infer that the shape coefficient i of the flat-headed projectile must be greater than 1.

[0024] [Reference 5] The third paragraph from the bottom of P389 states that “the aerodynamic forces acting on the projectile can be obtained through wind tunnel blowing, numerical calculation, engineering calculation, or extracted from flight test data.” [Reference 5] The last paragraph of P389 to the end of Section 15.5.1 of P391 states that “the zero-lift drag coefficient C of the projectile can be extracted from radar velocity measurement data. XO The above two points are the theoretical basis of the method for extracting the resistance coefficient of a homogeneous sphere of the present invention.

[0025] Other background technical information is as follows:

[0026] 1 About standard projectiles and standard ammunition: There are currently two ways to provide kinetic energy for standard projectiles: most of them use chemical charges to launch standard projectiles; a small part uses non-chemical charges to launch. The present invention mainly relates to launching standard projectiles with chemical charges, and its principle can also be used for launching non-chemical charges.

[0027] 1.1 Structural features of the barrel of a standard projectile: [Document 1] P3, first paragraph, line 3 states that “a cannon is usually composed of two major parts: the barrel and the gun carriage. The barrel consists of the barrel, breech block, etc. The barrel is the main body of the barrel, used to give the projectile an initial velocity and flight direction; the breech block is used to hold the breech block; the breech block is used to lock the barrel, fire the shells, and extract the cartridge after firing.” [Document 1] P36, page 2 states that “cannon firing generally involves burning gunpowder in a tubular container (i.e., the barrel) that is closed at one end. The high-temperature and high-pressure combustion gas generated expands and does work, pushing the projectile (i.e., the projectile) to accelerate toward the unclosed tube mouth (i.e., the muzzle) at the other end, obtaining the maximum ejection velocity (i.e., initial velocity) at the muzzle.”

[0028] At present, there are two main types of standard projectile barrels: rifled and smoothbore. [Reference 1] P47 page 6.1 Overview paragraph 3 Figure 6-1 shows the "outer outline diagram of the gun barrel and the shell after the barrel is in the chamber" of the standard rifled standard projectile. The figure shows the general structure of the breech, breech block, shell, barrel and muzzle brake. [Reference 1] P348 Section 18.1.4 Figure 18-5 shows the "diagram of the connection between the breech and the barrel and the base plate" of the smoothbore gun.

[0029] [Document 1] Page 57, Section 6.2.3, the first paragraph states: "Generally, the interior of the barrel is called the gun bore, and the inner bore is generally composed of a chamber, a ramp, and a guide portion"; the second paragraph states the chamber: "… Common chamber structures include four types: cartridge fixed chamber, cartridge split chamber, cartridge split chamber, and semi-combustible cartridge chamber"; the present invention takes the cartridge fixed chamber of a rifled projectile as an example. [Document 1] Page 59, the last paragraph states: "The ramp is divided into a smooth bore ramp and a rifled ramp"; Figure 6-22 shows a schematic diagram of the ramp structure; [Document 1] Page 60, the third paragraph states: "The part of the barrel bore that guides the projectile movement except the chamber and the ramp is called the guide portion. It is generally divided into two types: rifled and smooth bore."

[0030] Structural characteristics of standard projectiles: [Document 2] P8-13 states the following: P8 Section 1.3.2 Composition of artillery ammunition, the first paragraph states that "artillery ammunition is also artillery shells", P8 Section 2 states that "artillery shells consist of two parts: projectiles and propellant charges"; the composition of rifled artillery shells can be referred to " Figure 1-1 The composition of the shells”; P8, paragraph 4, states that “a projectile is usually composed of a fuze, a shell (shell) and a filling, etc.”; P8, paragraph 6, states that “the shell is the shell that holds the projectile filling and connects the various parts of the shell, and is divided into the warhead, the cylindrical part, the tail part, etc. The two ends of the cylindrical part have a centering part, a bullet belt (guide belt) and a closed air ring”; P11, paragraph 2, states that “the propellant charge is composed of propellant, cartridge, primer, and auxiliary components”; [Document 3] P173 Figure 4 -9 gives "charging structure diagram of a 100mm anti-aircraft gun"; [Document 3] P182 Figure 4-2 6 gives the "Mortar Charge Structure Diagram". The mortar shell is composed of 1-tail, 2-additional charge, 3-basic charge tube, 4-projectile, 5-explosive and 6-fuze. "Mortar charge is a charge with separate charges, which is composed of basic charge and additional charge. The basic charge is the basic charge tube. Usually, the basic charge tube, additional charge, projectile and fuse are packaged and stored separately. When shooting, the basic charge tube is installed first, and then an appropriate number of additional charge tubes are installed according to the range requirements.", "The mortar basic charge tube structure diagram is as follows Figure 4-2 7," From the figure, it can be seen that the bottom of the basic powder tube is the primer, and "the basic powder tube is placed in the tail tube 2.9 of the mortar shell." [Reference 2] P262-264 Figures 9-8 and 9-11 give the shape of the mortar shell body and point out that "the cylindrical part of the shell body is also called the centering part"; "In order to reduce the leakage of gunpowder gas, a closed air ring is often provided in the centering part or several annular grooves are processed."

[0031] [Reference 1] P464 The third to last paragraph states: "Due to processing errors in production, the mass of the projectiles varies. In order to prevent the dispersion from being affected by the large difference in projectile mass, a mass grading method is adopted. The mass symbols are divided into nine levels, as shown in Table 21-1." "The mass symbol of each bullet is determined according to Table 21-1, and the symbol should be written on the projectile body. The difference between a mass grading symbol and the mass of the standard bullet is ±1 / 3%. The heaviest four mass grading symbols are "++++", and the mass is 1 / 3% of the mass of the standard bullet. The lightest 4 quality classification symbols are “----”, and the quality is the standard bullet quality.

[0032] [Reference 2] Section 8.2.2 "Cartridge Structure" on P236 states that the length of the cylindrical part of the barrel mouth of the cartridge is approximately equal to the length of the cylindrical part of the tail of the projectile (generally (0.80-1.25) d). "The oblique shoulder is the transition part from the barrel mouth to the barrel body." "The shape of the barrel body should be adapted to the shape of the gun chamber, and is generally a truncated cone.";

[0033] [Reference 3] P1, Section 0.1.1 states that “artillery propelling charge is the general term for the gunpowder in ammunition and the various auxiliary components of the charge.” “Gunpowder charge provides the weapon with launching energy, and it is one of the key factors that determine the power of the weapon.”

[0034] [Reference 4] P205, Section 12.1, Gunpowder Charge Structure states: "Gunpowder charge structure design is to select the position of the propellant in the chamber, the structure of the ignition device, and other charge components when the ballistic plan and the shape and size of the gunpowder have been determined, so that the charge can meet the ballistic indicators and the requirements of production, transportation, storage, and service life." It also says that "charge structure has an important influence on interior ballistic performance... unreasonable charge structure will cause abnormal ballistics."

[0035] 2 About shooting accuracy, shooting accuracy, shooting density and data processing

[0036] [Document 5] P396, paragraph 6 states: "Weapon shooting accuracy consists of density and accuracy. Density refers to the degree to which a group of bullet impact points are scattered around the average bullet impact point, and accuracy refers to the degree to which the average bullet impact point deviates from the aiming point."

[0037] [Reference 2] Pages 22-25 also give a relatively detailed discussion on shooting accuracy, pointing out that the accuracy of a product is described by accuracy and density. Accuracy refers to the difference between the average value of multiple measurements of a sample and the true value. Density refers to the degree to which a group of impact points are scattered around the average impact point.

[0038] [Reference 2] P23, paragraph 7 states: "A large number of observations have shown that the coordinates of the projectile landing point relative to the average impact point are two-dimensional random variables on the plane and satisfy the normal distribution law." If the number of shots in a set of experiments is n, and the coordinates in space are X i , Y i , Z i The average values ​​of their test results are The intermediate deviation of coordinates X, Y, Z:

[0039]

[0040] 3 About the test method

[0041] 3.1 [Reference 7] pp. 73-85, 3.2 gives the "test method, data processing and commonly used speed measurement equipment for speed measurement test." [Reference 7] pp. 85-87, 3.3 gives the "selected charge test" method, [Reference 7] pp. 87-90 gives the "jump angle test" method, [Reference 7] pp. 94-104, 3.6 gives the "range and density test" method. [Reference 7] pp. 104-105 describes the implementation points and test equipment of the vertical target test. [Reference 7] pp. 109-126 describes the shooting test for determining the spatial coordinates of the projectile.

[0042] 3.2 [Reference 5] P383 "15.4.1 Main items of outdoor ballistic test" summarizes the test items in 3.1.

[0043] 3.3 People are eager to obtain a method with excellent technical effect to determine the density and jump angle accuracy of the projectile system.

[0044] Standard projectiles are thrown from standard projectiles. The function of standard projectiles and propellants is mainly to give standard projectiles a certain initial velocity and shooting angle, and the function of standard projectiles is to damage targets.

[0045] In the application, the user first assigns the shooting angle and shooting direction to the standard projectile, and the standard projectile fires the composite projectile at the same initial velocity. After the standard projectile hits the target, the coordinates of the landing point of the standard projectile are measured. Generally, three groups are fired at one shooting angle, and each group fires 5-10 standard projectiles. The distribution of landing points mostly follows a normal distribution.

[0046] The movement of standard projectiles in the air will be disturbed by various factors, causing them to deviate from the predetermined trajectory, and the landing points of each standard projectile will be scattered. Measure the distance and direction coordinates of the projectile point (X i, Z i ), the origin of the coordinate system can be the aiming point on the target surface, corresponding to the scattered impact points of the projectiles.

[0047] The precision of the product is described by accuracy and density. Accuracy refers to the difference between the average value of multiple measurements of the sample and the true value. Density refers to the degree of dispersion between the multiple measurement results of the sample and the average value. The accuracy index is completed by the unit designated by the state to compile the firing table. The density index is a very important indicator of the product. It determines the number and time required for the product to destroy the target, as well as the logistical support required to achieve this goal. Therefore, both the user and the unit providing the product attach great importance to it.

[0048] The dispersion of standard projectiles cannot be corrected, but can only be reduced. The greater the mean square error of the dispersion, the greater the consumption of standard projectiles to damage the target, the longer the shooting time, and the greater the chance of being counterattacked. Therefore, when designing standard projectiles and standard projectiles, it is hoped to know the mean square error of their dispersion.

[0049] The density cannot be accurately calculated at present, and its accurate determination is inseparable from the shooting test. This indicator is completed by a third party designated by the state through the test method.

[0050] People are eager to obtain a method with better operable technical effects to determine the density and jump angle accuracy of the projectile system. Summary of the invention

[0051] The purpose of the present invention is to provide a method for determining the density and jump angle accuracy of a projectile system with excellent technical effects.

[0052] The technical problems to be solved by the present invention are mainly:

[0053] First, the impact coordinates are needed to measure the density of the projectile system. The flight trajectory of the standard projectile launched by the standard projectile in the medium is composed of two parts: the center of mass motion of the oblong standard projectile and the centroidal motion around the center of mass generated by the angle between the axis of the standard projectile and its flight velocity vector line. When a standard projectile is launched by a standard projectile and the coordinates of the impact point of the standard projectile are measured, the density obtained includes the density of both the standard projectile and the standard projectile, that is, the combined density of the two.

[0054] The present invention provides a method: using a standard projectile and a standard propellant charge, a composite projectile modified from a standard projectile is launched from the barrel of the standard projectile, thereby separating the center of mass motion of the standard projectile and the center of mass motion of the axis of the standard projectile around the velocity vector line. The present invention maintains the maximum simulation degree of the original projectile system.

[0055] Secondly, the jump angle of the standard projectile given by the current test method changes with the target distance. The definition of the actual jump angle is: the angle between the initial velocity vector line and the axis of the gun body before shooting at the moment the projectile leaves the muzzle is called the jump angle of the standard projectile. The axis of the standard projectile before shooting is unique, the initial velocity vector line is also unique, and obviously the jump angle of the standard projectile is also unique. However, because in the current jump angle test method, the test jump angle changes with the jump angle target distance, the jump angle value also changes. Therefore, the jump angle data given by the current jump angle test method is inaccurate. The research conclusions on the law of jump angle changes based on such data are also questionable.

[0056] The firing angle in the firing table is composed of the ejector elevation angle and the jump angle. Since the jump angle currently given is inaccurate, the firing angle in the firing table is also inaccurate. The firing angle is the key factor that determines whether the weapon system can hit the target.

[0057] The firing angle is one of the core data for compiling the firing table. Therefore, if the jump angle is inaccurate during the preparation of the firing table, the firing angle in the firing table will also be inaccurate. According to industry practice, the accuracy of the product is described by accuracy and density: accuracy refers to the difference between the average value of multiple measurements of the sample and the true value. The accuracy index is completed by the unit designated by the state to compile the firing table. Density refers to the degree of dispersion between the multiple measurement results of the sample and the average value; the density index is a very important indicator of the product, which determines the number and time required for the product to destroy the target and the logistical support required to achieve this goal. Therefore, both the user and the unit providing the product attach great importance to it.

[0058] The dispersion of standard projectiles cannot be corrected, but can only be reduced. The greater the mean square error of the dispersion, the greater the consumption of standard projectiles to damage the target, the longer the shooting time, and the greater the chance of being counterattacked. Therefore, when designing standard projectiles and standard projectiles, it is hoped to know the mean square error of their dispersion.

[0059] The density cannot be accurately obtained by calculation at present, and the accurate determination of them cannot be separated from the shooting test. This indicator is usually completed by a third party designated by the state through the test method. The preferred test method for density is: the standard projectile uses the propellant to throw the projectile from the standard projectile; the function of the standard projectile and the propellant is mainly to give the projectile a certain initial velocity, shooting angle, and shooting direction; the function of the projectile is to damage the target;

[0060] The density test method is: first, the standard projectile is given a shooting angle, shooting direction and initial velocity, and the projectile is fired; after the projectile hits the target, the coordinates of the projectile impact point are measured. Generally, three groups are fired at one shooting angle, and each group shoots 5-10 projectiles; the distribution of the impact points obeys the normal distribution;

[0061] The present invention provides a method for shooting at a jump angle target at a certain distance, and the jump angle result provided can eliminate the influence of the aerodynamic jump angle, so that the jump angle does not change with the target distance. That is, the technical problem of how to obtain the real jump angle of the standard projectile in the prior art is solved, the accuracy of the shooting table is improved, thereby improving the efficiency of the launch system, and making the relevant analysis and research work more operable.

[0062] The present invention focuses on a method for determining the density and jump angle accuracy of a projectile system, wherein a standard projectile is used to project a composite projectile; the mass center motion trajectory of the composite projectile is composed of two parts: the mass center motion of component one 1 and the motion of the rotation axis of component two 2 around the mass center;

[0063] The composite projectile is composed of component 1 and component 2, wherein: component 1 is a homogeneous spherical body with a diameter the same as that of a standard projectile, and is a solid or hollow structure; the material is metal or non-metal or a composite thereof; the mass center of component 1 coincides with its geometric center and is at the center of the sphere; that is, when component 1 moves in a medium, the angle between the geometric axis of component 1 and its velocity vector line is zero, and the motion trajectory of component 1 leaving the standard projectile can be described by a three-degree-of-freedom particle motion differential equation; component 2 is a rotating body structure with a cross section consistent with the caliber of the standard projectile; component 2 is essentially a standard projectile or a partial structure of a standard projectile or a structure similar to a standard projectile; the mass of the composite projectile is the same as or similar to that of the standard projectile; the number of components 1 is at least one; further preferably: when gunpowder is used to launch the composite projectile, component 2 is a part of the standard projectile that can seal the gunpowder gas of the standard projectile;

[0064] The method for determining the density and jump angle accuracy of the projectile system is to launch the composite projectile composed of component 1 and component 2 using a standard projectile, and measure the following data accordingly: chamber pressure, shooting angle, initial velocity, meteorological conditions, drag coefficient of component 1, range, ground density, jump angle, intermediate error of jump angle, target density, and flight time (see the contents of document 5 "External Ballistics of Projectiles and Arrows" P383-387; and the relevant contents of document 7 P69-125); if enough drag coefficients of component 1 have been measured, the corresponding standard drag coefficient can be defined according to the measured data; in the technical field, it is also customarily referred to as the "standard air resistance law for spherical projectiles".

[0065] After the launch, the coordinates of the impact points of component 1 and component 2 are measured, and their density and jump angle accuracy are calculated accordingly; and on this basis, the density and jump angle accuracy of the ejector or projectile in the ejection system are determined; this is one of the key innovations of the present invention. In the prior art, only the following two types of data can be obtained: first, the comprehensive density composed of the ejector and the projectile; second, the jump angle accuracy including the aerodynamic jump angle as the target distance changes. The present invention eliminates the influence of the aerodynamic jump angle on the jump angle accuracy, and there is no need to consider the change of the target distance.

[0066] The method for determining the density and jump angle accuracy of the projectile system should meet the following requirements: First, after component 1 and component 2 fly away from the standard projectile, both obtain the same initial velocity and shooting angle, but the two have different ballistic coefficients, and the two should be separated from each other and should not affect each other's movement; that is, after the launch, the latter should be separated from the former and should not collide with the former; a high-speed camera is set up at the beginning of the trajectory to monitor the separation of component 1 and component 2 to ensure that the two do not interfere with each other; second, before launching, it is required to check component 1, and check whether the center of mass coincides with the center of the ball and its ellipticity. If it does not meet the requirements, it will not be selected as a test projectile; after launching, it is also required to check component 1 and check its ellipticity. If it does not meet the requirements, the corresponding data will not be used as valid test data. (In the method for determining the density and jump angle accuracy of the projectile system, it is required to select corresponding methods according to the test purpose to carry out various typical test processes.)

[0067] The method for determining the density and jump angle accuracy of the projectile system described in the present invention preferably claims the following technical contents:

[0068] The steps and requirements of the method for determining the density of the projectile system and the accuracy of the jump angle are:

[0069] ① Determine the purpose of the test, and prepare the test materials and test site; the test purpose is one of the following three: determine the density of the ejector in the ejection system, the density of the projectile, and the accuracy of the ejector's jump angle; the requirements for the preparation of test materials are: prepare composite projectiles that meet the requirements, launch power systems, and standard ejectors for testing; prepare test data measurement equipment;

[0070] ② Select the test method and prepare the test site;

[0071] First, use the direct-fire weapon density test method to determine the density of standard projectiles or projectile targets;

[0072] Second, the test is conducted using the distance shooting test method to determine the distance density of the standard projectile or projectile;

[0073] Third, use the test method of jumping angle shooting to test and determine the jumping angle and density of the standard projectile;

[0074] The test method selected in step ② of the method for determining the density of the projectile system and the accuracy of the jump angle is one of the following three or a combination thereof:

[0075] First, conduct tests according to the test method for neutral target density, i.e., direct-fire weapon density, in [Reference 7] P104-107 to determine the target density of standard projectiles or standard projectiles;

[0076] [Reference 7] gives the calculation method of density, the key points of measuring the range and ground density, the jump angle and the intermediate error of the jump angle, and the density of the vertical target: according to the direct shooting distance or effective shooting range of the standard projectile, a vertical target is set perpendicular to the ground at a certain distance from the mouth of the standard projectile and perpendicular to the shooting direction;

[0077] The standard projectile shoots a group of projectiles at the opposite target under the same shooting conditions (such as shooting direction, elevation angle, charge, projectile, etc.), and then measures the height coordinates (Y i ,Z i ), the coordinate origin is the aiming point on the target surface, according to (Y i ,Z i ) can calculate the high and low intermediate errors E y and direction intermediate error E z :

[0078]

[0079] Second, determine the distance density of standard projectiles or standard projectiles according to the "Range and Density" test in [Reference 7] P94-104 ("distance density" means "inflection density" or "range density", that is, the density corresponding to the distance, inflection or range);

[0080] Third, determine the jump angle and jump angle density of the standard projectile according to the jump angle test method in [Reference 7] P87-91.

[0081] Attached Figure 1 The present invention is applicable to the schematic diagram of the rifled type projectile, Figure 3 This is a schematic diagram of a smoothbore standard ejector. Figure 1 and attached Figure 2 And attached Figure 3 The characteristic is that component one 1 is in front of component two 2, which is used to determine the density and jump angle accuracy of the standard projectile. Figure 4 and attached Figure 5 The characteristic is that component two 2 is in front of component one 1, and the density and jump angle accuracy of the standard projectile and the standard projectile can be determined simultaneously.

[0082] The jump angle accuracy usually consists of two parts: jump angle density and jump angle accuracy ("jump angle accuracy" is commonly known as "jump angle"). The jump angle density of the standard projectile is described by the jump angle dispersion.

[0083] At the moment when the composite projectile leaves the launching port of the standard projectile (i.e., the moment when the composite projectile is separated from the mechanical connection with the gunpowder gas after being ejected from the launching port of the standard projectile), the angle between the velocity direction of the composite projectile and the axis of the barrel of the standard projectile before shooting is called the standard projectile jump angle; the projectile jump angle is a vector, and the jump angle in the plumb direction is called the vertical jump angle, or the height jump angle, which is often represented by the symbol γ. When the subscript is not marked, it refers to the vertical direction. The jump angle in the horizontal direction is often called the lateral jump angle, or the lateral direction jump angle, and the symbol is often represented by the symbol ω. The subscript is sometimes also marked according to different situations. For example, in the present invention, y or z is used to represent the height or lateral jump angle.

[0084] The test method of the standard projectile jump angle test is: set a jump angle target at a certain distance from the launch port of the standard projectile, and use the standard projectile to shoot at the jump angle target (such as [Reference 5] P385 Figure 15.4.2); the jump angle test is mostly carried out by flat shooting. (The elevation angle of the gun is generally no more than 2°), and the high and low component jump angles are met:

[0085] The present invention can use the formula in [Document 7] P87-91 to calculate the jump angle. The high and low components of the jump angle γ y The formula is based on [Reference 7]P88 formula (3-6):

[0086]

[0087] Calculate the lateral component of the jump angle ω z The formula is based on [Reference 7]P88 formula (3-7): Where: x is the distance to the target, y, z are the height and lateral coordinates of the impact point relative to the aiming point, respectively, m; g is the acceleration due to gravity, m / s 2 ; V p is the average flight speed of the projectile on its travel distance x, m / s;

[0088] When aiming at the crosshairs of the jump angle target, the vertical component γy of the jump angle and the horizontal component ω of the jump angle in the above two equations are z The actual test vertical jump angle γ is composed of the actual jump angle γ1 of the standard projectile and the aerodynamic jump angle γ2 of the projectile; the following formula holds: γ=γ1+γ2

[0089] In the present invention, because the composite projectile contains a homogeneous spherical component 1, when the component 1 moves in the medium, its angle of attack is zero, and thus does not contain an aerodynamic jump angle, γ2 does not change with the target distance and its value is 0, so the test jump angle γ is the real jump angle γ1 of the projectile. The key technical difficulty of the prior art is that there is currently no operable method for measuring the real jump angle γ1 of a standard projectile; the present invention creatively solves this technical difficulty by improving the projectile, improves the accuracy of the shooting table, and thereby obtains the accurate jump angle (accuracy) of the projectile launched by the projectile; and makes the relevant jump angle theory have practical significance and operability in practice.

[0090] In the prior art, since standard projectiles are usually oblong rigid bodies, their attack angle is not zero, so the jump angle data must change with the target distance. In the present invention, the attack angle of component 1 is zero, so the jump angle of component 1 does not change with the target distance.

[0091] ③ According to the requirements of the corresponding standard projectile and the initial velocity, chamber pressure, etc. when launching the corresponding standard projectile, select the corresponding launch power system solution; for example, for projectiles powered by gunpowder gas, select the specific charge amount according to the initial velocity and chamber pressure requirements;

[0092] ④ The initial velocity, chamber pressure, firing angle, and meteorological observation data should be measured for each launch, and the drag coefficient of the component 1 should be obtained in advance or measured on site;

[0093] ⑤ Set up a high-speed camera at the beginning of the trajectory to monitor the separation of component 1 and component 2; ensure that component 1 and component 2 do not interfere with each other; if interference occurs, the launch test and related data will be deemed invalid;

[0094] ⑥ Recover the homogeneous spherical body at the impact point and check its ellipticity to ensure that it remains a homogeneous spherical body during flight; if the requirements cannot be met, the launch test and related data will be deemed invalid;

[0095] ⑦ Measure the coordinates of the impact points of component 1 and component 2; then calculate and obtain one of the following data: catapult density, projectile density and jump angle accuracy; if you want to obtain the catapult density and projectile density, then after shooting, you should use the corresponding method in [Reference 7] P87-105, which has corresponding methods for standing target and distance shooting;

[0096] The coordinates of the impact points of component 1 and component 2 are measured; then one of the following data is calculated: the density of the projectile (the projectile is the projectile to be tested, which is mostly standard, but may also be a new type of launcher), the density of the projectile; the density of component 1 is the density of the projectile E1, and the density of component 2 is the combined density of the standard projectile and the standard projectile Es, and the corresponding projectile density is calculated by the formula: E s 2 =E1 2 +E2 2 Sure;

[0097] ⑧ If the jump angle accuracy of the projectile is to be obtained, a method and a data processing method for performing a jump angle test on a jump angle target using a composite projectile are used to obtain the jump angle density of the standard projectile, and the jump angle of the standard projectile is obtained accordingly; the usual method compared with this is to reversely calculate the jump angle of the projectile based on the average value of the impact point coordinates of the projectile jump angle density test; the efficiency and effect of the present invention are significantly improved.

[0098] If a vertical target or a jumping angle target is used, it is required to measure the height and direction coordinates of the impact point (Y i ,Z i ), calculate the high and low intermediate error E according to the following formula y and direction intermediate error E z :

[0099]

[0100] If it is a distance shooting test, i.e. a ground density test, it is required to measure the distance and direction coordinates (X i ,Z i ), according to (X i ,Z i ) can calculate the distance intermediate error E x and direction intermediate error E z :

[0101]

[0102] In the above formula, n is the number of composite projectile combinations launched, that is, the number of effective launches;

[0103] The corresponding X i , Y i , Z i The average value of .

[0104] The method for determining the density of the projectile system and the accuracy of the jump angle is characterized in that the method for determining the density of the projectile system and the accuracy of the jump angle meets one or a combination of the following requirements:

[0105] First, use one or a combination of the following methods to determine the resistance coefficient or resistance law CX of component 1 in the medium: qb f(M):

[0106] (i) Theoretical calculation to estimate the air resistance coefficient of component 1, i.e., a homogeneous spherical body;

[0107] (ii) Conducting wind tests in a wind tunnel to further determine the air resistance coefficient of a homogeneous spherical body;

[0108] (III) Determine the air drag coefficient of a homogeneous spherical body using Doppler radar; [Reference 5] The last paragraph of P389 to the end of Section 15.5.1 of P391 states that “the zero-lift drag coefficient C of a projectile or rocket can be extracted from radar velocity data. XO The principle of

[0109] Second, determine the flight state parameter K:

[0110] Assuming that the ballistic coefficients of component 1 and component 2 using the same drag law are C1 and C2 respectively, the ratio of C2 to C1 is defined as the flight state parameter of the composite projectile, denoted as K, and:

[0111] In the above formula, m1 and m2 are the masses of component 1 and component 2 respectively; i1 and i2 are the elastic moduli of component 1 and component 2 respectively; CX1 and CX2 are the resistance coefficients of component 1 and component 2 respectively;

[0112] Third, before and after the component 1 and the component 2 fly away from the standard ejector, the following criteria are used to determine which of the component 1 and the component 2 is in the front:

[0113] If C1 is less than C2 and K is greater than 1, it is required that component 1 is always in front of component 2 before and after the launch, so that component 2 will not interfere with the movement of component 1;

[0114] If C1 is greater than C2 and K is less than 1, it is required that component 1 is always behind component 2 before and after the launch, so that component 1 will not interfere with the movement of component 2;

[0115] The flight state parameter K is required not to be equal to 1, otherwise component 1 and component 2 will interfere with each other.

[0116] The method for determining the density of the projectile system and the accuracy of the jump angle meets one or a combination of the following requirements:

[0117] First, when conducting a test for determining the density of a standard projectile, component 1 is in front and component 2 is in the back, and the sum of the masses of component 1 and component 2 is required to be equal to the mass of the original standard projectile;

[0118] Second, component 1 and component 2 are separate or combined structures composed of multiple sub-components. When the number of component 1 is one, a high-density ball, such as a tungsten core ball, is required, but its cost is relatively high; when the number of component 1 is two, two balls are used in combination; for example, one of the two balls may be a copper ball and the other may be carbon steel or hard aluminum; wherein the high-density copper ball is located at the front relatively far from the base of the standard projectile;

[0119] Third, when gunpowder is used to launch a composite projectile, and component 2 is a super light bullet of a standard projectile that can seal the gas of a standard projectile, and the total mass of component 1 and component 2 in the composite projectile is equal to the mass of the super heavy bullet of the standard projectile; the composite projectile as a whole is equivalent to the standard projectile; at this time, the data that can be obtained from the test can be regarded as the effective test data of the standard projectile and the standard projectile;

[0120] The aforementioned "gunpowder launch" is the chemical charge or propellant charge in the prior art, which is a typical structure that can provide kinetic energy for the projectile (see [Document 3] "Principles and Technology of Gun Propellant Charge Design" by Wang Zeshan, P173). Figure 4 -9 100mm anti-aircraft gun charge structure diagram, P182 Figure 4-2 6 Mortar charge structure diagram) is: cartridge, propellant, primer; it is required to use the cartridge, propellant and primer of the original standard projectile as much as possible; or use a part of the original standard projectile under inspection to modify it; or modify other types of new structure standard projectiles that can seal the projectile gas according to the original standard projectile design drawings; the ultimate goal is to maintain its consistency as much as possible (while having a high degree of simulation), that is, to keep the vibration and initial disturbance of the projectile consistent with the vibration and initial disturbance of the standard projectile launched using the original standard projectile.

[0121] The method for determining the density of the projectile system and the accuracy of the jump angle is characterized in that: the method for determining the density of projectiles and projectiles in the projectile system also meets one or a combination of the following requirements:

[0122] First, when conducting a test for simultaneously determining the density of the projectile and the projectile, component 1 is at the back and component 2 is at the front, and at this time, it must be that the sum of the masses of component 1 and component 2 is less than or equal to the mass of the original standard extra-heavy projectile; because the standard projectile's projectile weight is divided into 9 mass classification symbols;

[0123] Second, in the test of simultaneously determining the density of projectiles and projectiles, gunpowder is used to launch a composite projectile, and component 2 is a standard projectile extra-light bullet that can seal the standard projectile gas, and when the total mass of component 1 and component 2 in the composite projectile is approximately equal to the mass of the extra-heavy bullet of the standard projectile, the composite projectile as a whole is equivalent to the standard projectile; at this time, the data that can be obtained from the test shall be regarded as the valid test data of the standard projectile and the standard projectile.

[0124] (Note: The projectile's jump angle is the projectile's aerodynamic jump angle;)

[0125] The method for determining the density of projectiles and projectiles in a projectile system also meets one or a combination of the following requirements:

[0126] First, in the test for determining the density of the projectile alone, the composite projectile meets the following requirements: the composite projectile component two 2 is at the rear and component one 1 is at the front;

[0127] Secondly, when the ejection system is a rifled standard ejector, when component 1 is in front, the modification requirements of component 2 are: ① remove the fuse and the oval part of the warhead; ② retain all parts of the rear part of the standard projectile, namely the centering part, the cylindrical part, the cylinder with the belt and the tail of the projectile; ③ at the same time, it is required to hollow out the inner cavity of the remaining part of the standard projectile, namely the rear part; ④ add a head screw 2.6 behind component 1 and in front of the first centering part, so that component 1 will not enter the internal cavity of the remaining part of the standard projectile, namely the centering part at the rear; ⑤ uniformly counterweight the head screw 2.6 and component 1 so that their mass is equal to the mass of the original standard projectile;

[0128] Third, in the composite projectile used in the standard rifled projectile, the launch power module 3 adopts the launch power module 3 and assembly method of the original standard launcher without any change, so as to ensure that the internal ballistic performance remains unchanged; that is, the launch power module 3 is composed of: a cartridge 3.1, a propellant 3.2, and a primer 3.3; wherein: the cartridge 3.1 is arranged at the rear of the tail of the component 2, the propellant 3.2 is arranged in the inner cavity of the cartridge 3.1, and the primer 3.3 is arranged at the rear of the cartridge 3.1; see the attached Figure 1 and attached Figure 2 ;

[0129] When the projectile system is a rifled standard projectile, in the composite projectile used by the standard rifled projectile, the composition of the launch power module 3 adopts the launch power system of the standard projectile as follows: cartridge 3.1, propellant 3.2, and primer 3.3; wherein: the cartridge 3.1 is arranged at the rear of the tail 2.5 of the component 2, the propellant 3.2 is arranged in the inner cavity of the cartridge 3.1, and the primer 3.3 is arranged at the rear of the cartridge 3.1;

[0130] Fourth, in the test of determining the density of the projectile separately, when the ejection system is a smoothbore standard projectile, component 2 2 is a part of the standard projectile or is modified from the standard projectile; the modification requirements are: component 2 2 removes the standard projectile fuse and the warhead oval part 2.1, and retains the air-closing ring 2.7 and other parts of the standard projectile; ③ At the same time, it is required to hollow out the inner cavity at the rear of the standard projectile; ④ and add a head screw 2.6 behind component 1 and in front of the first air-closing ring, so that component 1 will not enter the internal cavity of the air-closing ring 2.7 at the rear of the standard projectile; ⑤ It is uniformly counterweighted with component 1 so that its mass is equal to the mass of the original standard projectile; [Document 2] P262-264 Figures 9-8 and 9-11 give the shape of the mortar body. "The cylindrical part of the projectile is also called the centering part"; "In order to reduce the leakage of gunpowder gas, a gas-sealing ring is often provided in the centering part or several annular grooves are processed." Related explanation: The gas-sealing ring is located in the cylindrical part of the mortar shell. Since it is a smoothbore gun, some grooves are processed to reduce the leakage of gunpowder gas. The grooved part is called a gas-sealing ring.

[0131] The launching power module 3 adopts the launching power module 3 and assembly method of the original standard launcher without any changes to ensure that the internal ballistic performance remains unchanged; the launching power module 3 of the original standard launcher does not have a cartridge 3.1, and the cartridge 3.1 is a closed space formed by the tail of the airtight ring 2.7 of the warhead of the component 2 and the inner cavity of the barrel 4, and the additional powder bag of the propellant 3.2 is surrounded by the outside of the tail tube 2.9 of the tail part 2.5 of the component 2, and the basic powder tube and the primer 3.3 are arranged inside the tail tube 2.9 of the tail part 2.5 of the component 2, and are placed at the rear end of the tail part 2.5; see the attached Figure 3 .

[0132] Fifth, in the test of determining the density of the ejector separately, when the ejection system is a smoothbore standard ejector, in the composite projectile used by the standard smoothbore ejector, the launch power module 3 is a part of component two 2. The composition of the launch power module 3 is as follows: cartridge 3.1, propellant 3.2, primer 3.3; wherein: the cartridge 3.1 is a closed space formed by the cooperation of component two 2 and the inner cavity of the barrel 4, and the propellant 3.2 is composed of a basic cartridge 3.2.1 and an additional cartridge 3.2.2. The additional cartridge 3.2.2 is surrounded by the outside of the tail tube 2.9 of the tail portion 2.5 of component two 2, while the basic cartridge 3.2.1 and the primer 3.3 are arranged inside the tail tube 2.9 of the tail portion 2.5 of component two 2, and are placed at the rearmost part of the tail portion 2.5;

[0133] Sixth, when determining the density of the projectile and the projectile at the same time, the composite projectile meets the following requirements: ① The composite projectile component 2 should use a standard projectile with a mass of "extra light bullet" and be in front of the component 1; ② The end of the component 1 is close to the tail 2.5 of the rifled projectile component 2; or the end of the component 1 is close to the bottom of the tail tube 2.9 of the tail 2.5 of the smoothbore projectile component 2; ③ The mass of the composite projectile should be the same or similar to that of the standard projectile. ④ The composite projectile is a composite structure that uses chemical charges as the launching power; ⑤ The so-called "extra light bullet" refers to a standard projectile with a mass classification symbol "----" that is lighter than the standard standard bullet weight by 4 mass classification symbols, and the mass of one bullet weight mass classification symbol is ±1 / 3% of the standard bullet weight; the bullet weight mass classification symbol is partially equivalent to the meaning of the old "bullet weight symbol"; when the component 2 is at the back, it should be able to seal the gunpowder gas.

[0134] Seventh, when simultaneously determining the density of the projectile and the projectile and the accuracy of the jumping angle, when the projectile system is a rifled projectile, Component 1 is behind component 2. The modification requirements for component 1 are: ① A newly modified cartridge 3.1 is added to the rear of component 1. The best solution is to modify it with a standard cartridge. The mouth of the cartridge 3.1 is connected to the tail 2.5 of component 2. 2. Component 1 must be at the oblique shoulder of the cartridge 3.1; ② A bullet stopper 3.4 is added to the rear of the composite projectile component 1 to limit the position of component 1. The function of the bullet stopper 3.4 is to make the front of component 1 and the tail 2.5 of component 2 tightly fit; to prevent component 1 and component 2 from colliding with each other and causing explosion; ③ When adding a buffer pad, the buffer pad, component 1 and component 2 are uniformly weighted so that their total mass is equal to the mass of the original standard projectile; when adding a bullet stopper 3.4, component 1, component 2 and bullet stopper 3.4 should be uniformly weighted so that their total mass is equal to the mass of the original standard projectile; see attached Figure 4 ;

[0135] Eighth, when simultaneously determining the density of the ejector and the projectile and the accuracy of the jumping angle, when the ejection system is a smoothbore standard ejector, component 1 is behind component 2; a newly modified short cartridge is added behind component 1; ② to prevent component 1 and component 2 from colliding with each other and causing the chamber to explode; one method is to have a circular bullet-blocking plate 3.4 at the mouth of the short cartridge, the function of the bullet-blocking plate 3.4 is to make the end of component 1 and the tail 2.5 of component 2 tightly fit; ③ the propellant bag and the basic cartridge configured in the tail tube 2.9 of the tail 2.5 of component 2 are moved into the short cartridge; ④ the primer 3.3 configured in the tail tube 2.9 of the tail 2.5 of component 2 is de-fired; ⑤ the primer 3.3 is installed at the rear of the short cartridge, and the bullet-blocking plate 3.4 and components 1 and 2 are uniformly weighted so that their mass is equal to the mass of the original standard projectile; see attached Figure 5; The original standard projectiles have different mass levels. However, when the density of component one and component two is determined at the same time, the mass sum should be the mass of the extra heavy projectile; and when the density of the projectile is determined separately, the mass sum of the composite projectile should be the standard projectile weight. The mass of the same projectile weight level also has a range.

[0136] [Reference 3]P182 Figure 4-2 6 gives the "Mortar Charge Structure Diagram". The mortar shell is composed of 1-tail, 2-additional charge, 3-basic charge tube, 4-projectile, 5-explosive and 6-fuze as shown in the figure. "Mortar charge is a charge with separate charges, which is composed of basic charge and additional charge. The basic charge is the basic charge tube. Usually, the basic charge tube, additional charge, projectile and fuse are packaged and stored separately. When shooting, the basic charge tube is installed first, and then an appropriate number of additional charge tubes are installed according to the range requirements." "The mortar basic charge tube structure diagram is as follows Figure 4-2 7," It can be seen from the figure that the bottom of the basic powder tube is the primer, and "the basic powder tube is placed in the tail tube 2.9 of the mortar shell."

[0137] The method for determining the density of the projectile system and the accuracy of the jump angle meets one or a combination of the following requirements:

[0138] First, the density test of the composite projectile with component 1 in front and component 2 in the back can obtain the density and jump angle accuracy of the projectile;

[0139] Second, the density test of the composite projectile with component 2 in front and component 1 in the back can obtain the density of the projectile and the projectile at the same time; for the curved trajectory, the ground density is obtained; for the direct-fire weapon, the density of the vertical target is obtained; shooting at the jump angle target obtains the accuracy of the jump angle;

[0140] Third, the test method for determining the target and jump angle of the standard catapult meets the following requirements:

[0141] Key points for measuring the density of vertical targets: According to the direct shooting distance or effective shooting range of the standard projectile, a vertical target is set perpendicular to the ground at a certain distance from the mouth of the standard projectile and perpendicular to the shooting direction; the standard projectile shoots a group of composite projectiles at the vertical target under the same shooting conditions, and then measures the height coordinates (Y i ,Z i ), the coordinate origin is the aiming point on the target surface, according to (Y i ,Z i ) can calculate the high and low intermediate errors E y and direction intermediate error E z :

[0142]

[0143] Where: n is the number of composite projectile combinations launched, that is, the number of effective launches;

[0144] The corresponding Y i , Z i The average value of

[0145] The jump angle test uses flat shooting, that is, the elevation angle of the gun (generally no more than 2°), and the vertical jump angle is:

[0146]

[0147] The accuracy of standard projectiles is described by the jump angle, and the density of projectiles is described by the jump angle dispersion;

[0148] At the moment when the composite projectile leaves the launch port of the standard ejector or when the composite projectile loses mechanical contact with the gunpowder gas after leaving the launch port of the ejector, the angle between the composite projectile's velocity direction and the axis of the standard ejector barrel before shooting is called the standard ejector jump angle;

[0149] The test method of the standard projectile jump angle test is: a jump angle target is set at a certain distance from the standard projectile mouth, and the standard projectile shoots at the jump angle target;

[0150] The results of the measurement are: the test vertical jump angle γ, the real vertical jump angle γ1 of the standard ejector, and the aerodynamic jump angle γ2; and:

[0151] γ=γ1+γ2

[0152] According to the above theory and test results, γ2 varies with the target distance, so the test jump angle γ It also varies with the target distance; using the improved composite projectile, the aerodynamic jump angle γ2 corresponding to component 1 is zero, so in fact γ = γ1

[0153] The method for determining the density of the projectile system and the accuracy of the jump angle meets the following requirements:

[0154] The test jump angle in the jump angle test is composed of two parts: the standard projectile jump angle and the aerodynamic jump angle of the standard projectile. Since the aerodynamic jump angle changes with the target distance, the test jump angle also changes with the target distance. When compiling the basic ballistic parameters in the firing table, the gun installation angle is given. The relationship corresponding to the ballistic elements; the actual firing angle of the projectile out of the muzzle is θ, and it satisfies:

[0155] The density test method is: first, the standard projectile is given a shooting angle and a shooting direction, and the standard projectile launches the composite projectile at the same initial velocity; after the projectile hits the target, the coordinates of the projectile impact point are measured, and one shooting angle generally shoots three groups, and each group shoots 5-10 projectiles; the distribution of the landing points obeys the normal distribution;

[0156] The movement of projectiles in the air will be disturbed by various factors, causing them to deviate from the predetermined trajectory, and the landing points of each projectile will be scattered; then measure the distance and direction coordinates (X i ,Z i ), the origin of coordinates can be the aiming point of the target surface, according to (X i ,Z i ) can calculate the distance intermediate error E x and direction intermediate error E z :

[0157]

[0158] Corresponding to the projectiles fired multiple times, there are dispersed impact points;

[0159] The density evaluation method is: assuming that the density of the custom-made projectile is E1, the density of the projectile is E2, and the combined density of the two is E S ; Assuming that E1 and E2 are independent random variables; then, the relationship between them is: E s 2 =E1 2 +E2 2 .

[0160] The method for determining the density of the projectile system and the accuracy of the jump angle meets the following requirements:

[0161] First, the number of components 1 ejected by a standard ejector is one or more; when the number of components 1 is greater than 1, the masses of different components 1 are increased in sequence along the launching direction, with the muzzle of the ejector barrel being the front and the bottom of the ejector barrel being the back, that is, they are arranged in the order of the large mass at the front and the small mass at the back;

[0162] Standard projectiles project composite projectiles that meet one of the following requirements: using chemical charges to propel the projectiles, or using non-chemical charges to propel the projectiles;

[0163] Second, the launching power structure of the composite projectile meets the following requirements:

[0164] ① For rifled projectiles that do not use chemical charges to propel the projectile; there is at least one component 1; when the number of components 1 is greater than 1, their masses increase in sequence along the launch direction; along the launch direction, a launch power structure is provided on the last individual of the composite projectile to provide power for all individuals in the entire composite projectile;

[0165] ② For a rifled projectile that uses chemical charges to propel the projectile, a launch power module 3 is provided on the last unit of the composite projectile; the launch power module 3 serves as a launch power to provide the chamber pressure and initial velocity necessary for the launch of component 2 2 and all components 1 in the composite projectile; the launch power module 3 is composed of: a cartridge 3.1, a propellant 3.2, and a primer 3.3; wherein: the cartridge 3.1 is arranged at the rear of the composite projectile, the propellant 3.2 is arranged in the inner cavity of the cartridge 3.1, and the primer 3.3 is arranged at the rear of the cartridge 3.1;

[0166] When the ejection system is a rifled standard projectile, when component 1 is in front, the modification requirements of component 2 2 are: ① remove its fuse and warhead oval part 2.1; ② retain all parts of the rear part of the standard projectile, namely the centering part 2.2, the cylindrical part 2.3, the cylinder with the bullet belt and the tail part 2.5; ③ at the same time, it is required to hollow out the inner cavity of the rear part of the standard projectile; ④ and add a head screw 2.6 behind component 1 and in front of the first centering part, so that component 1 will not enter the internal cavity of the centering part 2.2 at the rear of the standard projectile; ⑤ uniformly counterweight it and component 1 so that the mass is equal to the mass of the original standard projectile;

[0167] When the ejection system is a rifled standard ejector and component 1 is at the rear, the modification requirements are: ① a cartridge 3.1 is added to the rear of component 1, and cartridge 3.1 is modified or re-customized from the local structure of the front end of the cartridge of the original standard projectile, i.e., the near end of the muzzle; the inner diameter of cartridge 3.1 is required to be the same as the outer diameter of the tail 2.5 of the standard projectile; ② a bullet baffle 3.4 is added to the rear of the composite projectile; or a bullet baffle 3.4 is added to the cartridge 3.1 behind component 1; to prevent component 1 and component 2 from colliding with each other and causing the chamber to explode; ③ when a buffer pad is added, the buffer pad, component 1 and component 2 are uniformly weighted so that the sum of their masses is equal to the mass of the original standard projectile; when a bullet baffle 3.4 is added, component 1 and component 2 are uniformly weighted so that the sum of their masses is equal to the mass of the original standard projectile.

[0168] When determining the accuracy of the projectile jump angle, the composite projectile meets the following requirements: in the composite projectile, component 2 is behind or in front of component 1; the composite projectile is a composite structure using chemical charge as a launching power; the composite projectile is also provided with a launching power module 3, and the launching power module 3 is arranged at the rear of the composite projectile;

[0169] First, when the ejection system is a smoothbore standard ejector and the component 2 2 is behind the component 1 1, the launch power module 3 is a part of the component 2 2; the launch power module 3 is composed of the following: cartridge 3.1, propellant 3.2, and primer 3.3; wherein: the cartridge 3.1 is a closed space formed by the cooperation of the component 2 2 and the inner cavity of the barrel 4, the propellant 3.2 is the propellant of the original structure of the component 2 2, and the primer 3.3 is the primer of the original structure of the component 2 2, which is arranged at the rear of the component 2 2;

[0170] Second, when the ejection system is a smoothbore standard ejector, and the component 2 2 is in front of the component 1 1, the launch power module 3 is composed of the following: cartridge 3.1, propellant 3.2, and primer 3.3; wherein: the cartridge 3.1 is arranged behind the component 1 1, the propellant 3.2 is arranged in the inner cavity of the cartridge 3.1, and the primer 3.3 is arranged at the rear of the cartridge 3.1;

[0171] For a smoothbore standard projectile, component 2 2 is a standard projectile or is modified from a standard projectile; the modification requirements are: component 2 2 removes the standard projectile fuse and the warhead oval part 2.1, and retains the gas-sealing ring 2.7 and other parts of the standard projectile; the bottom of the tail pipe 2.9 is an impact-type or electric-fired primer 3.3; for a smoothbore standard projectile, the composite projectile used meets one of the following requirements: first, it is composed of at least one component 1 and one component 2 2; second, it is composed of component 2 2 that can seal the standard projectile gas and at least two components 1;

[0172] Third, for a standard projectile of a sub-caliber, the composite projectile component 2 is modified from a standard projectile of a standard projectile, and the component 1 in the composite projectile is used to replace the core in the cartridge of the standard projectile of the sub-caliber; before launching, the component 1 is arranged inside the component 2, and the launching power module 3 is served by the power structure of the original component 2; the launching power module 3 is composed of: a cartridge 3.1, a propellant 3.2, and a primer 3.3; wherein: the cartridge 3.1 is arranged at the rear of the component 2, the propellant 3.2 is arranged in the inner cavity of the cartridge 3.1, and the primer 3.3 is arranged at the rear of the cartridge 3.1;

[0173] Fourthly, for projectiles without cartridges, their launching power module 3 is equivalent to that of standard projectiles; the specific requirements are: the additional charge of the propellant 3.2 is tied to the tail tube 2.9, and the primer 3.3 is at the bottom of the tail tube 2.9; when launching, the projectile slides down along the barrel 4 of the standard projectile and hits the firing pin at the bottom of the barrel 4, the primer 3.3 ignites the propellant 3.2, and the gunpowder gas shoots the projectile out of the barrel 4.

[0174] In addition: Some terms in this invention are self-defined and are specifically explained as follows:

[0175] The "projectile" refers to a projectile or rocket launcher, electromagnetic launcher, etc. with a barrel. "Standard projectile" refers to a rotating body structure with the same caliber as the barrel used for launching. "Standard projectile" and "standard projectile" refer to the projectile and projectile to be tested when the method described in the present invention is used for corresponding testing; in principle, they should be existing standard structures. "Standard projectile" refers to an existing projectile. "Standard propellant charge" refers to an existing standard propellant charge.

[0176] The rearmost unit of the composite projectile is provided with a power structure; for chemical charge projectiles, for projectiles with cartridges, it can be borrowed from [Document 3] P173 Figure 4 -9 The cartridge and other structures in the charge structure diagram of a 100mm anti-aircraft gun; for projectiles without cartridges, it can borrow [Document 3] P183 Figure 4 The cartridge and other structures in the .26 mortar charging structure diagram are designed so that the rearmost individual can provide power to launch all the individuals in the composite projectile.

[0177] For conventional standard ammunition launched by means of an oblong rigid body, since the trajectory of the standard ammunition after launch is a spiral trajectory, its jump angle will inevitably change with the target distance; after using the composite projectile containing the homogeneous spherical body component 1 of the present invention, the jump angle of the component 1 obtained will not change with the target distance, which makes the data measurable and stable, and improves the measurement accuracy of the shooting angle in the shooting table. This is of great significance to the establishment of a more complete shooting table.

[0178] The technical effects of the present invention are described as follows:

[0179] [Document 2] P34, paragraph 5 states that “due to the many influencing factors, it is not enough to rely solely on theory to analyze and calculate the effects and performance of ammunition, so various tests must be conducted to check the manufacturing quality of ammunition. Among the various tests, the most decisive is the shooting test at the shooting range.” There are 9 main shooting range test items, of which two are related to external ballistic performance: “② Shooting density and maximum range”; “③ Flight stability and flight correctness;” ④ The preparation of shooting tables also needs to be completed through shooting range tests.

[0180] These tests consume a large amount of ammunition. Generally, three groups of shooting are required for one shooting angle, with 5-10 rounds in each group. However, the density data obtained is indeed the comprehensive data of the standard projectile and the standard projectile. If the comprehensive data cannot meet the requirements of tactical and technical indicators, the research and development unit urgently needs to know whether it is a problem with the standard projectile or the standard projectile. The present invention solves this problem.

[0181] Shooting range tests run through all stages of the product and consume a lot of ammunition. For example, [Reference 5] P399 only points out the range and density test items and jump angle test items in the shooting table shooting test: In the jump angle test, a standard projectile requires 21 rounds; to determine the table jump angle, 3 guns are needed, which will require 63 rounds of ammunition. For the range and density test items, only for one charge number, 3-5 shooting angles are required, and 3 groups of shooting at each shooting angle, each group of 7 rounds, that is, 63-105 rounds. It accounts for more than half of the total ammunition consumption of the shooting table shooting test.

[0182] The invention provides an experimental method for scientific and technological personnel to study the motion of the center of mass of projectiles and the motion law around the center of mass in the future.

[0183] [Document 5] P395 The last paragraph states: "The firing table is the basic document for troops to use weapon systems for combat and training. The firing table provides ballistic data for firing command and effectively exerting the combat effect of the firepower system. This data includes the table of the corresponding relationship between the elevation angle, firing direction and target position of the artillery (rocket launcher) required for firing at a given target position under standard conditions, which is called the basic element table.

[0184] The test jump angle in the jump angle test is composed of the standard projectile jump angle and the aerodynamic jump angle of the standard projectile. Since the aerodynamic jump angle changes with the target distance, the test jump angle currently obtained also changes with the target distance. When the shooting table is compiled, the shooting angle θ0 is is the standard ejector elevation angle, and satisfies: The shooting angle is one of the core data for compiling a shooting table. Therefore, if the jump angle is inaccurate during the preparation of the shooting table, the prepared shooting table will also be inaccurate.

[0185] In fact, the existing technology can only obtain the comprehensive density E S , but cannot get the standard ejector density E1 and standard projectile density E2; and E1 and E2 are exactly what the task-providing unit, the standard ejector manufacturing unit and the standard projectile manufacturing unit most want to know.

[0186] In order to distinguish the standard projectile and composite projectile used in the present invention from the standard projectile and standard projectile in the prior art, we call the projectile currently used and prepared for inspection a standard projectile, the projectile in the present invention is a new type of combined composite projectile, and the standard projectile in the prior art is the source of component 2 in the composite projectile in the present invention.

[0187] Supplementary explanation of the theoretical basis of the present invention:

[0188] The standard projectiles used in standard ejectors are all oblong rigid bodies. After leaving the muzzle, the flight trajectory of the oblong rigid standard projectile in the air is composed of two parts: the center of mass motion of the oblong standard projectile and the centroidal motion around the center of mass generated by the angle between the axis of the standard projectile and its flight velocity vector line. In this way, the density of the landing point includes the density of the standard ejector and the standard projectile.

[0189] The present invention changes the oblong standard projectile in the prior art into a composite projectile, and the composition of the composite projectile is as follows: a homogeneous spherical body (i.e., component 1), and a component 2 2 modified or imitated from the standard projectile; after the composite projectile flies out of the barrel of the standard projectile, component 1 can fly independently, and the axis of the homogeneous spherical body as component 1 always coincides with the direction of the velocity vector of the motion, and the nutation angle of the motion is zero; the homogeneous spherical body as component 1 is a rigid projectile, which can be regarded as a particle moving in the air; therefore, the motion trajectory of component 1 can be accurately described by the differential equation of particle motion; the present invention calculates the jump angle based on the vacuum trajectory, and should be processed according to the air trajectory in actual engineering applications; the differential equation of particle motion in the air trajectory refers to formula (3.2.2) in 3.2.1 of [Document 5] P76 and its related explanation.

[0190] The density test method is: first, the standard projectile is given a shooting angle and a shooting direction, and the standard projectile launches the composite projectile at the same initial velocity. After the projectile hits the target, the coordinates of the projectile impact point are measured. Generally, three groups are fired at one shooting angle, and each group shoots 5-10 projectiles; the point distribution obeys the normal distribution;

[0191] The elevation angle in the shooting table is the difference between the shooting angle and the jump angle. Therefore, the jump angle is an important parameter in the preparation of the shooting table. The jump angle given by the current jump angle test is the sum of the gun jump angle and the aerodynamic jump angle of the projectile. The aerodynamic jump angle of the projectile changes with the target distance, so the jump angle given in the current shooting table preparation is not the angle between the elevation line and the ray. Therefore, the shooting accuracy of the shooting table will be greatly reduced. This is a problem that the shooting table preparation has long wanted to solve. The present invention solves this technical problem and fills the gap in related technologies; it will definitely have pioneering and important significance in related technical fields and extended engineering application fields. BRIEF DESCRIPTION OF THE DRAWINGS

[0192] The present invention is further described in detail below in conjunction with the accompanying drawings and embodiments:

[0193] Figure 1 A schematic diagram showing the application principle of a composite projectile for a rifled gun with component 1 in front;

[0194] Figure 2A schematic diagram showing the application principle of a composite projectile for a rifled gun with component 1 in front;

[0195] Figure 3 A schematic diagram showing the application principle of a composite projectile for a smoothbore ejector with component 1 in front;

[0196] Figure 4 A schematic diagram showing the application principle of a composite projectile for a rifled projectile with component 1 at the rear;

[0197] Figure 5 The figure is a simplified diagram showing the application principle of a composite projectile for a smoothbore ejector with component 1 at the rear. DETAILED DESCRIPTION

[0198] The meanings of the accompanying drawings are as follows: component one 1, component one A1.1, component one B1.2; component two 2, warhead oval part 2.1, centering part 2.2, cylindrical part 2.3, belt part 2.4, tail part 2.5, head screw 2.6, air-sealing ring 2.7, tail fin 2.8, tail pipe 2.9; launching power structure 3, cartridge case 3.1 (section line omitted), propellant 3.2, basic cartridge case 3.2.1, additional cartridge case 3.2.2; primer 3.3, bullet stopper 3.4; barrel 4.

[0199] Figure 2 In the figure, there are two components 1, the one with higher density is in the front and closer to the front exit of the transmitter;

[0200] In various embodiments of the present invention, unless otherwise specified, the material of the homogeneous spherical projectiles is metallic copper.

[0201] Example 1 A method for determining the density of large-caliber rifled projectiles individually

[0202] 1.1 Test Purpose: To determine the density of large-caliber rifled projectiles (see Figure 1 ).

[0203] 1.2 Test equipment:

[0204] 1.2.1 The rifled projectile is selected from the 130 mm cannon in Table 1-1 Characteristics of Standard Projectiles in Document 4, P11, with a caliber of d = 0.130 m. The standard projectile is a fragmentation projectile, and the mass of the standard projectile is Mt = 33.4 kg.

[0205] 1.2.2 The launching power system is composed of (component three 3) a cartridge 3.1 of a standard projectile, a propellant 3.2 and a primer 3.3 (both the propellant 3.2 and the primer 3.3 are standard);

[0206] 1.2.3 The composite projectile consists of component 1 and component 2, with component 1 in front and component 2 in the back;

[0207] 1.2.4 The configuration diagram of the barrel, projectile and launching power system is attached. Figure 1 ;

[0208] 1.3 Estimate the flight state parameter K of the projectile: (In the present invention, q and m both refer to mass)

[0209] 1.3.1 Component 1 is a homogeneous, solid sphere. The mass of spheres with different densities is shown in m1 in Table 1. Since the mass of the standard projectile is known to be 33.4 kg (kilograms), Component 2 is a hollow cylindrical swirl made of carbon steel. The modification method is:

[0210] First, the oval part of the bullet nose of the standard projectile is removed, and the other parts of the standard projectile are retained, such as the centering part, the cylindrical part, the belt that encloses the gunpowder gas, and the tail part that is combined with the cartridge case;

[0211] Second, remove the explosives from the projectile and add a screw in front of the centering part at the front to separate the homogeneous spherical body from the projectile after turning the inner bore;

[0212] Third, the mass of the projectile body, the head screw 2.6 and the counterweight of the component 1 after turning the inner cavity is as shown in Table 1 m2; m2 = Mt-m1

[0213] 1.3.2 The elastic coefficient i1 of Annex 1, which takes a sphere as the standard air resistance law, is 1, and the elastic coefficient i2 of Component 2 of the hollow cylindrical body of revolution, which takes a sphere as the standard air resistance law, should be greater than 1.

[0214] 1.3.3 Estimate the flight state parameter K of the projectile:

[0215] Flight status parameter K:

[0216] 1.3.4 The flight state parameters of different materials are shown in Table 1. It can be seen from Table 1 that only material tungsten satisfies the flight state parameter K greater than 1, that is, when the projectile flies away from the muzzle of the ejector, component one 1 is in front and component two 2 is behind, and they do not interfere with each other;

[0217] 1.3.5 This embodiment uses Scheme 1. Component 1 is a solid homogeneous material of tungsten, with a mass m1 of 18.98 kg. The material of the modified component 2 is carbon steel, and the modified mass m2 is 14.42 kg. The flight state parameter K>1, component 1 is in front, component 2 is in the back, and the launch power system component 3 follows closely.

[0218] Table 1

[0219] Scheme number 1 2 3 4 5 6 Material Name Tungsten brass Carbon Steel Malleable cast iron Super hard aluminum nylon Density (g / cm3) 16.5 8.8 7.8 7.2 2.9 1.11 <![CDATA[Component 1: A homogeneous spherical body with a mass of m1 (kg)]]> 18.98 10.12 8.97 8.28 3.34 1.15 <![CDATA[The counterweight mass m2 (kg) of Component 2]]> 14.42 23.28 24.43 25.12 30.06 32.25 <![CDATA[m1 / m2]]> 1.316 0.435 0.367 0.330 0.111 0.036 Flight state parameters K of different materials ＞1.316 0.435 0.367 0.33 0.11 0.036

[0220] 1.4 Overview of test methods and data processing

[0221] 1.4.1 Carry out shooting test and data processing according to reference [Reference 7] P94, Section 3.6 "Shooting test for determining various parameters of landing point trajectory (range, density test)";

[0222] 1.4.2 Determine the purpose of the test according to 1.1, prepare the test equipment according to 1.2, estimate the flight state parameter K according to 1.3, and formulate a test implementation plan;

[0223] 1.4.3 Set up a high-speed camera at the beginning of the trajectory to monitor the separation of component 1 and component 2. Ensure that component 1 and component 2 do not interfere with each other.

[0224] 1.4.4 Test the firing angle, initial velocity, chamber pressure, meteorological conditions, and use Doppler radar to measure the drag coefficient of component 1 and component 2;

[0225] 1.4.5) Check whether the initial velocity and chamber pressure corresponding to the charge meet the requirements. If not, conduct a charge selection test. The charge ω is generally selected between the charge of standard propellant and the charge of standard strong charge. And: ω=ω0+Δω

[0226] Where: ω0 is the amount of standard charge, Δ ω is the correction amount for the standard charge;

[0227] 1.4.6 Recover the homogeneous spherical body at the impact point and check its ellipticity to ensure that it remains a homogeneous spherical body during flight, so as to determine the validity of the data;

[0228] 1.4.7 Each group of 10 rounds is fired at a ground target, the coordinates of the landing points of the homogeneous spherical body are measured, and the density of the landing points of component 1 is calculated. This density is the density of the rifled projectile.

[0229] Example 2 A method for determining the density of rifled projectiles individually (component 1 is two metal balls)

[0230] 2.1 Test purpose: To determine the density of large-caliber rifled projectiles (see Appendix Figure 2 ).

[0231] 2.2 Test equipment:

[0232] 2.2.1 Rifled projectiles are selected in [Reference 4]d, P11 "Table 1-1 Characteristics of standard projectiles", the 130 mm cannon with serial number 12 has a caliber of d = 0.130 m. The standard projectile is a fragmentation projectile, and the mass of the standard projectile is Mt = 33.4 kg.

[0233] 2.2.2 The launch power module assembly 3 is composed of a standard projectile cartridge 3.1, a standard propellant 3.2 and a standard primer 3.3;

[0234] 2.2.3 The composite projectile is composed of component 1 and component 2, with component 1 in front and component 2 in the back. Since tungsten is a precious metal, component 1 in Example 1 is changed to consist of two homogeneous metal balls. The material of the front homogeneous metal ball is brass and marked as component 1 A1.1, followed by a metal ball made of carbon steel and marked as component 1 B1.2. Their weights are shown in Table 1, respectively. 1.1 =10.12kg, and m 1.2 =8.97kg, at this time the weight of the component 2 is m2 = 14.31kg;

[0235] 2.2.4 Divide the component 2 into two parts, one of which is adjacent to the homogeneous metal ball made of carbon steel, and the weight of the ball together with the head screw is m 2.1 = 8kg. The second part contains the belt of enclosed gunpowder gas, weighing m 2.2 =6.31kg. See the attached schematic diagram of its structure Figure 2 .

[0236] 2.2.5 The configuration diagram of the barrel, projectile and launching power system is attached. Figure 2 ;

[0237] 2.3 Estimate the flight state parameter K of the projectile: (In the present invention, q and m both refer to mass)

[0238] 2.3.1 Flight state parameter K of component A1.1 and component B1.2 is specifically K 21 :

[0239]

[0240] Component A1.1 and component B1.2 are both homogeneous spheres, and their elastic coefficients relative to the standard air resistance law of spheres are the same, both 1. In the above formula, the mass of component A1.1 is m1 = 10.12 kg, and the mass of component B1.2 is m2 = 8.97 kg, so the flight state parameter K 21 If it is greater than 1, component A1.1 is in front and component B1.2 is in the back. They do not interfere with each other.

[0241] 2.3.2 Estimation of flight state parameter K of component 1 B1.2 and first type component 2

[0242] Component 1 B1.2 is a homogeneous spherical body, and the elastic coefficient of the standard air resistance law based on the spherical body is 1. In the above formula, the mass of component 1 B1.2 is m1=8.97kg, and the mass of component 2 is m2=8kg. Therefore, the flight state parameter K is greater than 1. Component 1 B1.2 is in front, and component 2 B1.2 is in the back. The two do not interfere with each other.

[0243] 2.3.3 Estimation of flight state parameter K of two components 2 in Table 2

[0244] From Table 2, it can be seen that both components 2 are carbon steel metal cylindrical swivel bodies, and their elastic coefficients can be regarded as similar. The mass of the former component 2 is m1 = 8kg, and the mass of the latter component 2 is m2 = 6.31kg. Therefore, the flight state parameter K should also be greater than 1. The first component 2 is matched with component 1 in front, and the second component 2 is in the back. The two should not interfere with each other. The order of the two flying can be determined from the high-speed photography results. If the two interfere with each other, the interference will not affect the test results.

[0245] The estimated results are shown in Table 2, and the schematic diagram of the ejection system is shown in the attached Figure 2 .

[0246] 2.4 Overview of experimental methods and data processing

[0247] 2.4.1 Carry out shooting test and data processing according to reference [Reference 7] P94, Section 3.6 "Shooting test for determining various parameters of landing point trajectory (range, density test)";

[0248] 2.4.2 According to the test objectives determined in 2.1, the test equipment prepared in 2.2, and the flight state parameter K estimated in 2.3, formulate a test implementation plan;

[0249] 2.4.3 Set up a high-speed camera at the beginning of the trajectory to monitor the separation of component 1 and component 2. Ensure that component 1 and component 2 do not interfere with each other.

[0250] 2.4.4 Test the firing angle, initial velocity, chamber pressure, and use Doppler radar to measure the drag coefficient of component 1 and component 2;

[0251] 2.4.5 Check whether the initial velocity and chamber pressure corresponding to the charge meet the requirements. If not, conduct a charge selection test. The charge ω is generally selected between the charge of standard propellant and the charge of standard strong charge. And: ω=ω0+Δω

[0252] Where: ω0 is the amount of standard charge, Δ ω is the correction amount for the standard charge;

[0253] 2.4.6 Recover the homogeneous spherical object at the impact point and check its ellipticity to ensure that it remains a homogeneous spherical object during flight, so as to determine the validity of the data;

[0254] 2.4.7 Each group of 10 shots is fired at a ground target. The coordinates of the landing points of the homogeneous spherical bodies are measured respectively, and the density of the landing points is calculated respectively. This density is the density of the rifled projectile.

[0255] The corresponding range of the copper ball is X1, and the density is E 11 , the range of the metal carbon steel ball is X2, and the density is E 12 , then the density of the ejector is: E1=(E 11 / X1+E 12 / X2) / 2

[0256] Table 2 Estimation results of flight state parameter K

[0257] Arrangement from the muzzle Component 1 A1.1 Component 1 B1.2 The first component 2 The second component 2 Component form ball ball Cylindrical solid Cylindrical body of revolution with elastic band Component Materials Homogeneous brass sphere Homogeneous carbon steel sphere Carbon Steel Carbon Steel Density (g / cm3) 8.8 7.8 7.8 7.8 Mass of each component m(kg) 10.12 8.97 8 6.31 Elastic shape coefficient i of each component 1 1 ＞1 ＞1 <![CDATA[m1 / m2]]> 10.12 / 8.97 8.97 / 8 8 / 6.31 Estimation of K ＞1.128 ＞1.121 ＞1.268

[0258] When calculating, the elastic coefficient of the cylindrical body is greater than that of the homogeneous spherical body. The elastic coefficient of the homogeneous spherical body is equal to 1. i2>1, but i2 is taken as 1 when calculating in this table;

[0259] 2.5 The rest of the contents are the same as those in Example 1 and are omitted here.

[0260] Example 3 A method for simultaneously determining the density of standard projectiles and standard projectiles

[0261] 3.1 Test Purpose: To determine the density of large-caliber rifled projectiles and projectiles (see Appendix Figure 4 ).

[0262] 3.2 Test equipment:

[0263] 3.2.1 The rifled projectile is selected from the 130 mm cannon in Table 1-1 Characteristics of Standard Projectiles in Document 4, P11, with a caliber of d = 0.130 m. The standard projectile is a fragmentation projectile, and the mass of the standard projectile is Mt = 33.4 kg.

[0264] 3.2.2 The standard weight of a standard projectile is known to be Mt = 33.4 kg. The weight of a qualified projectile should be within ±4 weight symbols. The heaviest is 34.402 kg and the lightest is 32.398 kg.

[0265] 3.2.3 The launching power system is composed of (component three 3) a cartridge 3.1 of a standard projectile, a propellant 3.2 and a primer 3.3; (the propellant 3.2 and the primer 3.3 are both standard)

[0266] 3.2.4 Composite projectile component: 1. The selected material is a homogeneous spherical body made of nylon, with a weight of m1 = 1.15 kg;

[0267] 3.2.5 The extra-light projectile selected as the standard projectile in composite projectile component 2 has a weight of 32.509 kg.

[0268] According to the table of quality classification symbols in Table 21-1 on P465 of [Reference 1], the weight range of a bullet weight quality classification symbol is:

[0269] 33.4×(±1 / 3%)=±0.1113(kg)

[0270] The heaviest mass of the extra heavy bullet is 33.4×(1+0.03)=34.402kg, and the lightest mass of the extra light bullet is 33.4×(1-0.03)=32.398kg. If the component 2 is a special light bullet with a heavy mass classification symbol of "---", the sum of the components 1 and 2 will not exceed 34.402kg. If the original standard propellant charge is still used, the ejection system can still maintain the ballistic performance requirements of the original standard ejection system.

[0271] 3.2.6 Component 1 is closely attached to the bottom of component 2 and in close contact with the tail of component 2. Component 2 is in front of the composite projectile and component 1 is in the back;

[0272] 3.2.7 The sum of the weights of component 1 and component 2 is 1.15kg + 32.398kg = 33.548kg. A bullet-blocking structure is added to the oblique shoulder of the standard cartridge case of the standard projectile to position component 1. The structure can be a bullet-blocking plate or a groove machined on the oblique shoulder of the cartridge case of the standard projectile. The purpose is to position component 1 and prevent component 1 from colliding with component 2 and causing chamber explosion. The weight of the structure cannot exceed 0.854kg.

[0273] 3.2.8 The propellant charge adopts the standard propellant charge, and the propellant charge amount of the standard propellant charge does not need to be changed in this embodiment;

[0274] 3.3 Calculation of flight state parameters

[0275] 3.3.1 Calculation of the elastic modulus of spherical component 1

[0276] The shape coefficient of the spherical bullet according to the standard resistance law of spherical bullet is i1=1, and the shape coefficient of the spherical bullet according to the resistance law of 1943 is i1>1.

[0277] 3.3.2 Determine the shape coefficient of the extra-light component 2

[0278] According to the test, based on the air resistance law of 1943, the ballistic coefficient of the ultra-light bullet component 2 is 0.471, and its shape coefficient is 0.93, which is approximately 1. (Source: [Document 4] P11 Table 1-1). The drag coefficient of the spherical bullet is greater than the drag coefficient of the 1943 drag law, and the shape coefficient of component 2 is less than that of component 1; therefore, the shape coefficient of the spherical bullet is greater than that of component 2; i1>i2.

[0279] 3.3.3 Calculate flight status parameters:

[0280] The material selected for component 1 is nylon, with a mass of m1 = 1.15 kg, and the mass of component 2 is m2 = 32.398 kg;

[0281] According to the air resistance law of spherical bullets, the shape coefficient i2 of component 2 must be much smaller than the shape coefficient i1 of component 1. The calculation results are shown in Table 3.

[0282] 3.3.4 This embodiment selects scheme 6, and the flight state coefficient K is much smaller than 1, that is, component two 2 is in front and component one 1 is in the back, and component two 2 will not interfere with the movement of component one 1.

[0283] 3.4 Overview of test methods and data processing:

[0284] 3.4.1-3.4.6 Same as Example 1

[0285] 3.4.7 Each group of 10 rounds is fired at ground targets, and the coordinates of the landing points of the homogeneous spherical body and the special light bullet are measured respectively. At the same time, the density of the impact points of component 1 and component 2 based on the range is calculated.

[0286] 3.4.8 The density of component 2 measured in this test is the comprehensive density, denoted as E S , the density of component 1 is the density of the standard ejector, recorded as E1;

[0287] 3.4.9 The method for calculating the density of component 2 is: Assuming that the density of the standard projectile is E1, and the density of the standard projectile is E2, the combined density of the two is E S . Assume that the density E1 and E2 are independent random variables. Then, the relationship between them conforms to: E s 2 =E1 2 +E2 2

[0288] The density of standard projectiles is as follows: E2 2 =E S 2 -E1 2

[0289] Table 3

[0290] Scheme number 1 2 3 4 5 6 Material Name Tungsten brass Carbon Steel Malleable cast iron Super hard aluminum nylon Density (g / cm3) 16.5 8.8 7.8 7.2 2.9 1.11 <![CDATA[Component 1 (1) Homogeneous spherical body with mass m1 (kg)]]> 18.98 10.12 8.97 8.28 3.34 1.15 <![CDATA[Component 2 (2) selects a very light spring with a mass of m2 (kg)]]> - - - - - 32.398 <![CDATA[m1 / m2]]> - - - - - 0.035 K - - - - - ＜0.035

[0291] Example 4 An example of determining the density of small-caliber rifled projectile targets (see attached Figure 4 )

[0292] 4.1 Test purpose: To determine the density and jump angle of the target of the 12.7mm large-caliber machine gun rifle standard ejector.

[0293] 4.2 Test equipment:

[0294] 4.2.1 Rifled projectile is a standard rifled projectile. The standard rifled projectile is the 12.7 mm large-caliber machine gun No. 3 in Table 1-1 Characteristics of standard projectiles in [Reference 4] P11. The caliber is d = 0.0127 mm. According to the 1943 air resistance law, the ballistic coefficient is 3.155, and the bullet shape coefficient is 0.94. It is known that the weight of the standard bullet that launches the standard projectile is an armor-piercing incendiary bullet is Mt = 0.0483 kg;

[0295] It is known that the standard weight of a standard projectile is 0.0483kg. The qualified projectile weight should be within ±4 projectile weight symbols. The heaviest is 0.0497kg and the lightest is 0.0469kg.

[0296] 4.2.2 The launch power system is composed of (component three 3) a standard projectile cartridge 3.1, a standard propellant 3.2 and a standard primer 3.3;

[0297] 4.2.3 Composite projectile component: The material of the composite projectile is a homogeneous spherical body made of nylon, with a weight of m1 = 0.00119 kg;

[0298] 4.2.4 The weight of the special light projectile selected as the standard projectile in the composite projectile component 2 is 0.0469 kg; the total weight of the two is 0.0481 kg;

[0299] In summary, in this embodiment, component 1 is a nylon ball, weighing 0.00119kg, and component 2 uses a standard weight projectile, weighing 0.0481kg. Component 2 is in front, and component 1 is in the back. (Note: If component 2 is a special light projectile, the maximum weight of the nylon ball can be a rigid sphere of 0.0028kg)

[0300] 4.2.5 Component 1 is closely attached to the bottom of component 2 and in close contact with the tail of component 2. Component 2 is in front of the composite projectile and component 1 is in the back;

[0301] 4.2.6 The total weight of component 1 and component 2 is 0.0481 kg. A bullet-blocking structure is added to the oblique shoulder of the standard cartridge case of the standard projectile to position component 1. The structure can be a bullet-blocking plate or a groove machined on the oblique shoulder of the cartridge case of the standard projectile. The purpose is to position component 1 and prevent component 1 from colliding with component 2 and causing a chamber explosion.

[0302] 4.3 Estimate the flight state parameter K of the projectile:

[0303] The flight status parameter table of components one and two of the same caliber is as follows:

[0304] According to the test, according to the 1943 air resistance law, the ballistic coefficient of component 2 is 3.155, and the shape coefficient is 0.94. The drag coefficient of the spherical bullet is greater than the drag coefficient of the 1943 drag law, and the shape coefficient of component 2 is less than the shape coefficient of component 1; therefore, the shape coefficient of the spherical bullet is greater than the shape coefficient of component 2; i1>i2. . This embodiment uses scheme No. 6. The mass of component 2 is greater than the mass of component 1. Obviously, the flight state parameter K<1, and the calculation results are shown in Table 4. That is, component 2 is in front and component 1 is in the back, and component 1 will not interfere with the movement of component 2. See the attached schematic diagram of the ejection system. Figure 4

[0305] 4.4. Overview of the test method for density:

[0306] 4.4.1 Carry out the test and data processing according to 3.7 “Standing Target Test” of reference [Reference 7] P104:

[0307] 4.4.2-4.4.7 are the same as 1.4.2-1.4.7 of Example 1

[0308] Table 4

[0309] Scheme number 1 2 3 4 5 6 Material Name Tungsten brass Carbon Steel Malleable cast iron Super hard aluminum nylon Density (g / cm3) 16.5 8.8 7.8 7.2 2.9 1.11 <![CDATA[Component 1: A homogeneous spherical body with a mass of m1 (kg)]]> 0.01769 0.009435 0.008363 0.007719 0.00311 0.00119 <![CDATA[Mass m2 (kg) of Component 2, which is extremely lightweight and elastic]]> - - - - - 0.0469 <![CDATA[m1 / m2]]> - - - - - 0.0254 K - - - - - ＜0.0254

[0310] Example 5 An Example for Determining the Jump Angle and Jump Angle Density of a Medium Caliber Rifled Anti-aircraft Gun Projectile

[0311] 5.1 Test purpose: to determine the jump angle and jump angle density of the standard projectile

[0312] 5.2 Test equipment:

[0313] 5.2.1 The ejector is selected from Table 1-1 Characteristics of Standard Projectiles in [Reference 4] P11, No. 6, 2. Standard 57mm anti-aircraft gun, the standard ejector is a tracer fragmentation grenade of the same caliber, and the weight of the standard projectile is Mt = 2.8kg;

[0314] 5.2.2 The launch power system is composed of (component three 3) a standard projectile cartridge 3.1, a standard propellant 3.2 and a standard primer 3.3;

[0315] 5.2.3 The material of the homogeneous spherical projectile component 1 of this patent is metal tungsten, and the mass is about m1 = 1.599 kg;

[0316] 5.2.4 Component 2 of the enclosed gunpowder gas, use a modified standard projectile projectile, such as the attached Figure 1 , the reform method is:

[0317] First, remove the warhead fuze and oval part of the standard projectile, and retain the other parts of the standard projectile, such as the centering part, the cylindrical part, the belt that encloses the gunpowder gas, and the tail part combined with the cartridge case;

[0318] Second, remove the explosives from the projectile and add a screw in front of the centering part at the front to separate the homogeneous spherical body from the projectile after turning the inner bore;

[0319] Third, the mass of the projectile and the head screw after turning the inner cavity is m2=1.201kg.

[0320] 5.3 Estimation of the flight state parameter K of the composite projectile: (q and m both represent weight)

[0321] 5.3.1 According to the standard resistance law of spherical bullet, the shape coefficient i1 of the spherical bullet is 1. At this time, the shape coefficient i2 of component 2 must be greater than the shape coefficient of component 1; that is, greater than 1;

[0322] 5.3.2 Estimation of flight state parameter K

[0323] The flight status parameter table of components one and two of the same caliber is as follows:

[0324]

[0325] Component 2 is a hollow cylindrical body of rotation, i2 is greater than the elastic coefficient i1 of the homogeneous sphere, i1 = 1, and this example uses solution 1. m1>m2, the flight state coefficient K is greater than 1, component 1 is in front of component 2, and component 2 will not interfere with the movement of component 1.

[0326] 5.4 Overview of test methods and data processing:

[0327] 5.4.1 The test method can be adopted. In addition to the test and data processing according to the reference [Reference 7] P87, Section 3.4 "Determination of jump angle test", the following should also be achieved:

[0328] 5.4.2-5.4.7 Same as Example 1.4.2-1.4.7

[0329] Table 5

[0330] Scheme number 1 2 3 4 5 6 Material Name Tungsten brass Carbon Steel Malleable cast iron Super hard aluminum nylon Density (g / cm3) 16.5 8.8 7.8 7.2 2.9 1.11 <![CDATA[Mass m1 (kg) of Annex 1]]> 1.599 0.853 0.756 0.698 0.281 0.1076 <![CDATA[The mass m2 (kg) of Annex 2]]> 1.201 1.947 2.044 2.102 2.519 2.6924 <![CDATA[m1 / m2]]> 1.331 0.438 0.3698 0.3320 0.1115 0.0400 K ＞1.331 ＞0.438 ＞0.3698 ＞0.3320 ＞0.1115 ＞0.0400

[0331] Example 6 Method for determining the density of smoothbore standard projectiles (mortars)

[0332] 6.1 Test purpose: To determine the density of a single smoothbore standard projectile (see Appendix Figure 3 ).

[0333] 6.2 Test equipment:

[0334] 6.2.1 The smoothbore projectile is a standard smoothbore projectile. The standard projectile caliber d = 0.082 meters is selected from "Table 1-1 Characteristics of standard projectiles" on page 11 of [Reference 4]. The standard mass of the standard projectile is 3.10 kg.

[0335] 6.2.2 The launching power system is the launching power system of the original standard projectile;

[0336] 6.2.3 The material of the homogeneous spherical projectile in this embodiment is metal carbon steel, with a mass of about 2.251 kg, see Table 6;

[0337] 6.2.4 Component 2 of the sealed gunpowder gas uses a modified standard projectile projectile with a mass of 0.849 kg. The structure is as shown in the figure Figure 1 , the reform method is:

[0338] First, remove the oval part of the warhead of the standard projectile and retain the other parts of the standard projectile;

[0339] Second, remove the explosives from the projectile and add a screw in front of the centering part at the front to separate the homogeneous spherical body from the projectile after turning the inner bore;

[0340] Third, the mass of the projectile body and head screw after turning the inner cavity is about 0.849 kg;

[0341] Fourthly, to ensure shooting safety, the primer can be changed to an electric-shock primer.

[0342] 6.3 Calculation of flight status parameters

[0343] Calculate the weight m1 of several different density materials of accessory 1. In order to make the weight of accessory 1 and accessory 2 3.15kg, the weight of accessory 2 after weighting is as shown in the following table m2. Since component 2 is made of carbon steel, the material of component 1 is also selected as carbon steel, m1 = 2.251kg, and the mass of component 2 after modification is m2 = 0.849kg.

[0344] The shape coefficient i1 of the spherical bullet using the standard drag law is 1. At this time, the shape coefficient i2 of the hollow cylindrical body of the component 2 using the drag law is definitely greater than the shape coefficient of the component 1. The shape coefficient i2 of the component 2 is greater than the shape coefficient i1 of the homogeneous sphere. i1=1 The flight state parameter table of the components 1 and 2 of the same caliber is:

[0345]

[0346] This embodiment uses Scheme 3, and the flight state coefficient K is greater than 1, that is, component 1 is in front and component 2 is in the back, and component 2 will not interfere with the movement of component 1. The estimation results are shown in Table 6, and the schematic diagram of the ejection system is shown in the attached Figure 3 .

[0347] 6.4 Overview of test methods and data processing:

[0348] 6.4.1-6.4.7 are the same as 1.4.1-1.4.7 of Example 1.

[0349] Table 6

[0350]

[0351] Example 7 An Example of Determining the Jump Angle and Jump Angle Density of a Standard Projectile

[0352] 7.1 Test purpose: To determine the jump angle and jump angle density of standard projectiles

[0353] 7.2 Test equipment:

[0354] 7.2.1 The ejector is a standard ejector corresponding to the embodiment of the present invention;

[0355] 7.2.2 The structure of the composite projectile may be selected from one of the composite projectiles in Examples 1 to 6 of the present invention;

[0356] 7.3 The test method can be adopted. In addition to the test and data processing according to the reference [Reference 7] P87, Section 3.4 "Determination of jump angle test", the following should also be done:

[0357] 7.3.1 Clarify the purpose of the test

[0358] 7.3.2 Preparation of test equipment

[0359] 7.3.3 Estimate the flight state parameter K and formulate a test implementation plan;

[0360] 7.3.4 Set up a high-speed camera at the beginning of the trajectory to monitor the separation of component 1 and component 2. Ensure that component 1 and component 2 do not interfere with each other.

[0361] 7.3.5 Test the firing angle, initial velocity, chamber pressure, and use Doppler radar to measure the drag coefficient of component 1 and component 2;

[0362] 7.3.6 Check whether the initial velocity and chamber pressure corresponding to the charge meet the requirements. If not, conduct a charge selection test. The charge ω is generally selected between the charge of standard propellant and the charge of standard high-intensity charge. And:

[0363] ω=ω0+Δω

[0364] Where: ω0 is the amount of standard charge, Δ ω is the correction amount for the standard charge;

[0365] 7.3.7 Recover the homogeneous spherical object at the impact point and check its ellipticity to ensure that it remains a homogeneous spherical object during flight in order to determine the validity of the data;

[0366] 7.3.8 Fire 5 to 10 rounds in each group at the hopping angle target, measure the coordinates of the impact point of the homogeneous spherical body, and calculate the hopping angle density and hopping angle. The density and hopping angle are the density and hopping angle of the projectile.

[0367] 7.4 Calculation of the jump angle of the standard projectile. The coordinates of the impact point of the close-range target on the homogeneous spherical body are measured, and its density and jump angle are calculated. The ballistic descent is calculated using vacuum ballistics;

[0368] 7.5 Calculation of the jump angle of a standard projectile. For example, when shooting at a long-distance target, the ballistic descent is calculated using the differential equations of the projectile center of mass motion taking into account air resistance. For specific methods, refer to the vertical target shooting test.

Claims

1. A method for determining the density and jump angle accuracy of a projectile system, characterized in that: The composite projectile is ejected using a standard projectile; the mass center motion trajectory of the composite projectile is composed of two parts: the mass center motion of component one (1) and the motion of the rotation axis of component two (2) around the mass center; The composite projectile is composed of a component one (1) and a component two (2), wherein: the component one (1) is a homogeneous spherical body with a diameter the same as the caliber of the standard projectile, and is a solid or hollow structure; the material is metal or non-metal or a composite thereof; the mass center of the component one (1) coincides with its geometric center and is at the center of the sphere; that is, when the component one (1) moves in the medium, the angle between the geometric axis of the component one (1) and its velocity vector line is zero, and the motion trajectory of the component one (1) leaving the standard projectile can be described by a three-degree-of-freedom particle motion differential equation; the component two (2) is a rotating body structure with a cross section consistent with the caliber of the standard projectile; The composite projectile has the same or similar mass as the standard projectile; the number of component one (1) is at least one; The method for determining the density and jump angle accuracy of the projectile system is to launch a composite projectile composed of component one (1) and component two (2) using a standard projectile, and correspondingly measure the following data: chamber pressure, shooting angle, initial velocity, meteorological conditions, drag coefficient of component one (1), range, ground density, jump angle, intermediate error of jump angle, target density, and flight time; if enough drag coefficients of component one (1) have been measured, then the corresponding standard drag coefficient can be defined according to the measured data; After the launch is completed, the coordinates of the impact points of component one (1) and component two (2) are measured, and their density and hop angle accuracy are calculated based on the coordinates; and on this basis, the density and hop angle accuracy of the ejector or projectile in the ejection system are determined; The method for determining the density and jump angle accuracy of the projectile system should meet the following requirements: first, after component one (1) and component two (2) fly away from the standard projectile, both obtain the same initial velocity and shooting angle, but the two have different ballistic coefficients, and the two should be separated from each other and not affect each other's movement; second, before launching, component one (1) must be checked to see whether the center of mass coincides with the center of the ball and its ellipticity. If the requirements are not met, it will not be selected as the test projectile; after launching, component one (1) must also be checked to see whether the ellipticity is consistent with the center of the ball. If the requirements are not met, the corresponding data will not be used as valid test data; The steps and requirements of the method for determining the density of the projectile system and the accuracy of the jump angle are: ① Determine the purpose of the test, and prepare the test materials and test site; the test purpose is one of the following three: determine the density of the ejector in the ejection system, the density of the projectile, and the accuracy of the ejector's jump angle; the requirements for the preparation of test materials are: prepare composite projectiles that meet the requirements, launch power systems, and standard ejectors for testing; prepare test data measurement equipment; ② Select the test method and prepare the test site; First, use the direct-fire weapon density test method to determine the density of standard projectiles or projectile targets; Second, the test is conducted using the distance shooting test method to determine the distance density of the standard projectile or projectile; Third, use the test method of jumping angle shooting to test and determine the jumping angle and density of the standard projectile; ③ According to the requirements of the corresponding standard projectile and the initial velocity and chamber pressure when launching the corresponding standard projectile, select the corresponding launch power system solution; ④ The initial velocity, chamber pressure, firing angle, and meteorological observation data shall be measured for each launch. The drag coefficient of component one (1) shall also be obtained in advance or measured on site; ⑤ Set up a high-speed camera at the beginning of the trajectory to monitor the separation of component one (1) and component two (2); ensure that component one (1) and component two (2) do not interfere with each other; if interference occurs, the launch test and related data will be deemed invalid; ⑥ Recover the homogeneous spherical body at the impact point and check its ellipticity to ensure that it remains a homogeneous spherical body during flight; if the requirements cannot be met, the launch test and related data will be deemed invalid; ⑦ Measure the coordinates of the impact points of component one (1) and component two (2); then calculate and obtain one of the following data: projectile density, projectile density, and jump angle accuracy; ⑧ If the jump angle accuracy of the projectile is to be obtained, the jump angle density of the standard projectile is obtained by using the jump angle test method and data processing method on the jump angle target, and the jump angle of the standard projectile is obtained accordingly; If a vertical target or a jumping angle target is used, it is required to measure the height and direction coordinates of the impact point (Y i ,Z i ), calculate the high and low intermediate error E according to the following formula y and direction intermediate error E z : If it is a distance shooting test, i.e. a ground density test, it is required to measure the distance and direction coordinates (X i ,Z i ), according to (X i ,Z i ) can calculate the distance intermediate error E x and direction intermediate error E z : Where n is the number of composite projectile combinations launched, that is, the number of effective launches; The corresponding X i , Y i , Z i The average value of The method for determining the density of the projectile system and the accuracy of the jump angle meets one or a combination of the following requirements: First, determine the resistance coefficient or resistance law CX of component one (1) in the medium using one or a combination of the following methods: qb f(M): (i) theoretical calculation to estimate the air resistance coefficient of component one (1), i.e., a homogeneous spherical body; (ii) Conducting wind tests in a wind tunnel to further determine the air resistance coefficient of a homogeneous spherical body; (iii) Determining the drag coefficient of a homogeneous spherical body by using Doppler radar; Second, determine the flight state parameter K: Assuming that the ballistic coefficients of component one (1) and component two (2) using the same drag law are C1 and C2 respectively, the ratio of C2 to C1 is defined as the flight state parameter of the composite projectile, denoted by K, and: In the above formula, m1 and m2 are the masses of component 1 (1) and component 2 (2), respectively; i1 and i2 are the elastic moduli of component 1 (1) and component 2 (2), respectively; Third, before and after component one (1) and component two (2) fly off the standard projectile, the following criteria shall be used to determine which component one (1) or component two (2) is in front: If C1 is less than C2 and K is greater than 1, it is required that component one (1) is always in front of component two (2) before and after launch, so that component two (2) will not interfere with the movement of component one (1); If C1 is greater than C2 and K is less than 1, it is required that component one (1) is always behind component two (2) before and after launch, so that component one (1) will not interfere with the movement of component two (2); The flight state parameter K is required not to be equal to 1, otherwise component one (1) and component two (2) interfere with each other.

2. The method for determining the density and jump angle accuracy of a projectile system according to claim 1, characterized in that: The method for determining the density of the projectile system and the accuracy of the jump angle meets one or a combination of the following requirements: First, when conducting the test for determining the density of the standard projectile, component one (1) is in front and component two (2) is in the back, and the sum of the masses of component one (1) and component two (2) is required to be equal to the mass of the original standard projectile; Secondly, component one (1) and component two (2) are separate or a combination structure consisting of multiple sub-components.

3. The method for determining the density and jump angle accuracy of a projectile system according to claim 1, characterized in that: The method for determining the density of projectiles and projectiles in the projectile system and the accuracy of the jump angle also meets one or a combination of the following requirements: First, when conducting a test for simultaneously determining the density of the projectile and the projectile, component one (1) is at the rear and component two (2) is at the front, and at this time, it must be the case that: the sum of the masses of component one (1) and component two (2) is less than or equal to the mass of the original standard extra heavy bullet; Secondly, in the test for simultaneously determining the density and jump angle accuracy of projectiles and projectiles, gunpowder is used to launch a composite projectile, and component two (2) is a special light projectile that can seal the standard projectile gas, the total mass of component one (1) and component (2) in the composite projectile is not greater than the mass of the special heavy projectile of the standard projectile, and the composite projectile as a whole is equivalent to the standard projectile; the data that can be obtained from the test at this time shall be regarded as the effective test data of the standard projectile and the standard projectile.

4. The method for determining the density and jump angle accuracy of a projectile system according to claim 2, characterized in that: The method for determining the density of projectiles and projectiles in the projectile system and the accuracy of the jump angle also meets one or a combination of the following requirements: First, in the test for determining the density of the projectile alone, the composite projectile meets the following requirements: the composite projectile component two (2) is at the rear and component one (1) is at the front; Secondly, when the projectile system is a rifled standard projectile, when component one (1) is in front, the modification requirements of component two (2) are: ① remove the fuse and the oval part (2.1) of the warhead; ② retain all parts of the rear part of the standard projectile, namely the centering part (2.2), the cylindrical part (2.3) and the cylindrical belt part (2.4) and the tail part (2.5); ③ at the same time, the inner cavity of the remaining part of the standard projectile is hollowed out; ④ and a head screw (2.6) is added behind component one (1) and in front of the first centering part, so that component one (1) does not enter the inner cavity of the centering part (2.2) of the remaining part of the standard projectile; ⑤ it is uniformly weighted with component one (1) so that the mass is equal to the mass of the original standard projectile; Third, in the composite projectile used in the standard rifled projectile, the launch power module (3) adopts the launch power module (3) and assembly method of the original standard launcher without any change, that is, the launch power module (3) is composed of: a cartridge (3.1), a propellant (3.2), and a primer (3.3); wherein: the cartridge (3.1) is arranged at the rear of the tail of the second component (2), the propellant (3.2) is arranged in the inner cavity of the cartridge (3.1), and the primer (3.3) is arranged at the rear of the cartridge (3.1); Fourth, in the test of determining the density of the projectile separately, when the projectile system is a smoothbore standard projectile, component two (2) is a part of the standard projectile or is modified from the standard projectile; the modification requirements are: component two (2) removes the standard projectile fuse and the warhead oval part (2.1), and retains the air-closing ring (2.7) and other parts of the standard projectile; ③ At the same time, it is required to hollow out the inner cavity at the rear of the standard projectile; ④ and add a head screw (2.6) behind component one (1) and in front of the first air-closing ring, so that component one (1) does not enter the internal cavity of the air-closing ring (2.7) at the rear of the standard projectile; ⑤ It is uniformly weighted with component one (1) so that the sum of their masses is equal to the mass of the original standard projectile; The launch power module (3) adopts the launch power module (3) and assembly method of the original standard launcher without any change; the launch power module (3) of the original standard launcher is provided with a cartridge (3.1), the cartridge (3.1) is a closed space formed by the closed air ring (2.7) of the second component (2) and the inner cavity of the barrel (4), the additional powder bag of the propellant (3.2) is surrounded by the outside of the tail tube (2.9) of the tail part (2.5) of the second component (2), and the basic powder tube and the primer (3.3) are arranged inside the tail tube (2.9) of the tail part (2.5) of the second component (2) and are placed at the rearmost part of the tail part (2.5); Fifth, in the test of determining the density of the projectile alone, when the projectile system is a smoothbore standard projectile, in the composite projectile used by the standard smoothbore projectile, the launch power module (3) is a part of the second component (2); the launch power module (3) is composed of the following: a cartridge (3.1), propellant (3.2), and a primer (3.3); wherein: the cartridge (3.1) is a dense structure formed by the cooperation of the second component (2) and the inner cavity of the barrel (4); The closed space acts as a propellant (3.2) composed of a basic powder tube (3.2.1) and an additional powder bag (3.2.2); the additional powder bag (3.2.2) is surrounded by the outside of the tail tube (2.9) of the tail part (2.5) of the component two (2), while the basic powder tube (3.2.1) and the primer (3.3) are arranged inside the tail tube (2.9) of the tail part (2.5) of the component two (2) and are placed at the rearmost part of the tail part (2.5); Sixth, when simultaneously determining the density and jump angle accuracy of the projectile and the projectile, the composite projectile shall meet the following requirements: ① The composite projectile component 2 (2) shall be a standard projectile with a very light mass and shall be located in front of the component 1 (1); ② The end of the component 1 (1) shall be in close contact with the tail section (2.5) of the rifled projectile component 2 (2); or the end of the component 1 (1) shall be in close contact with the bottom of the tail tube (2.9) of the tail section (2.5) of the smoothbore projectile component 2 (2); ③ The mass of the composite projectile shall be the same or similar to that of the standard projectile; ④ The composite projectile is a composite structure that uses chemical charge as the launching power; ⑤ The so-called very light mass refers to a standard projectile that is 4 mass classification symbols "----" lighter than the standard projectile, and the mass of one mass classification symbol of the projectile weight is ±1 / 3% of the standard projectile weight; Seventh, when simultaneously determining the density of the ejector and the projectile and the accuracy of the jumping angle, when the ejection system is a rifled ejector, the component one (1) is behind the component two (2), and the modification requirements for the component one (1) are: ① a newly modified cartridge is added to the rear of the component one (1), the mouth of the cartridge (3.1) is connected to the tail (2.5) of the component two (2), and the component one (1) must be at the oblique shoulder of the cartridge (3.1); ② a bullet stopper (3.4) is added to the rear end of the composite projectile component one (1) to limit the position of the component one (1), and the bullet stopper (3.4) is added to the rear end of the composite projectile component one (1). The function of the spring plate (3.4) is to make the front part of the component one (1) and the tail part (2.5) of the component two (2) fit tightly together, so as to prevent the component one (1) and the component two (2) from colliding with each other and causing the chamber to explode; ③ When a buffer pad is added, the buffer pad, the component one (1) and the component two (2) are uniformly weighted so that the sum of their masses is equal to the mass of the original standard projectile; when a bullet-blocking plate (3.4) is added, the component one (1), the component two (2) and the bullet-blocking plate (3.4) are uniformly weighted so that the sum of their masses is equal to the mass of the original standard projectile; Eighth, when simultaneously determining the density of the ejector and the projectile and the accuracy of the jumping angle, when the ejection system is a smoothbore standard ejector, component one (1) is behind component two (2); a newly modified short cartridge is added behind component one (1), ② to prevent component one (1) and component two (2) from colliding with each other and causing the chamber to explode; a method is to have a circular bullet-blocking plate (3.4) at the mouth of the short cartridge, the function of which is to make the end of component one (1) and the tail of the bullet of component two (2) closely fit. ③ The propellant (3.2) bag outside the tail tube (2.9) of the tail part (2.5) of the second component (2) and the propellant in the basic tube and the propellant of the accessories are moved into the short cartridge case, ④ the primer (3.3) in the tail tube (2.9) of the tail part of the second component (2) is removed, ⑤ the primer (3.3) is installed at the rear of the short cartridge case, and the bullet blocking plate (3.4) is uniformly weighted with the first component (1) and the second component (2) so that the sum of their masses is equal to the mass of the original standard projectile.

5. The method for determining the density and jump angle accuracy of a projectile system according to claim 1, characterized in that: The method for determining the density of the projectile system and the accuracy of the jump angle meets one or a combination of the following requirements: First, the density test of the composite projectile component one (1) in front and component two (2) in the back can obtain the density and jump angle accuracy of the projectile; Secondly, the density and jump angle accuracy test of the composite projectile with component 2 (2) in front and component 1 (1) in the back can obtain the density and jump angle accuracy of the projectile and the projectile at the same time; for the curved trajectory, the ground density is obtained; for the direct-fire weapon, the density of the vertical target is obtained; and for shooting at the jump angle target, the jump angle accuracy is obtained; Third, the test method for determining the target and jump angle of the standard catapult meets the following requirements: Key points for measuring the density of vertical targets: According to the direct shooting distance or effective shooting range of the standard projectile, a vertical target is set perpendicular to the ground at a certain distance from the mouth of the standard projectile and perpendicular to the shooting direction; the standard projectile shoots a group of composite projectiles at the vertical target under the same shooting conditions, and then measures the height coordinates (Y i ,Z i ), the coordinate origin is the aiming point on the target surface, according to (Y i ,Z i ) can calculate the high and low intermediate errors E y and direction intermediate error E z : Where n is the number of composite projectile combinations launched, that is, the number of effective launches; The corresponding Y i , Z i The average value of The jump angle test uses flat shooting, that is, the elevation angle of the gun And satisfy: vertical jump angle The accuracy of standard projectiles is described by the jump angle, and the density of projectiles is described by the jump angle dispersion; At the moment when the composite projectile leaves the launch port of the standard ejector or when the composite projectile loses mechanical contact with the gunpowder gas after leaving the launch port of the ejector, the angle between the composite projectile's velocity direction and the axis of the standard ejector barrel before shooting is called the standard ejector jump angle; The test method of the standard projectile jump angle test is: a jump angle target is set at a certain distance from the standard projectile mouth, and the standard projectile shoots at the jump angle target; The results of the measurement are: the test vertical jump angle γ, the real vertical jump angle γ1 of the standard ejector, and the aerodynamic jump angle γ2; and: γ=γ1+γ2 γ2 varies with the target distance, so the test jump angle γ It also varies with the target distance; when using a composite projectile, the aerodynamic jump angle γ2 corresponding to its component one (1) is zero, so in fact γ=γ1.

6. The method for determining the density and jump angle accuracy of a projectile system according to claim 4, characterized in that: The method for determining the density of the projectile system and the accuracy of the jump angle meets the following requirements: The test jump angle in the jump angle test is composed of two parts: the standard projectile jump angle and the aerodynamic jump angle of the standard projectile. Since the aerodynamic jump angle changes with the target distance, the test jump angle also changes with the target distance. When compiling the basic ballistic parameters in the firing table, the gun installation angle is given. The relationship corresponding to the ballistic elements; the actual firing angle of the projectile out of the muzzle is θ0, and it satisfies: The density test method is: first, the standard projectile is given a shooting angle and a shooting direction, and the standard projectile fires the composite projectile at the same initial velocity; after the projectile hits the target, the coordinates of the projectile impact point are measured, and three groups are fired at one shooting angle, with 5-10 projectiles fired in each group; the distribution of the landing points obeys the normal distribution; The movement of projectiles in the air will be disturbed by various factors, causing them to deviate from the predetermined trajectory, and the landing points of each projectile will be scattered; then measure the distance and direction coordinates (X i ,Z i ), the origin of coordinates can be the aiming point of the target surface, according to (X i ,Z i ) can calculate the distance intermediate error E x and direction intermediate error E z : Corresponding to the projectiles fired multiple times, there are dispersed impact points; The density evaluation method is: assuming that the density of the custom-made projectile is E1, the density of the projectile is E2, and the combined density of the two is E S ; Assume that E1 and E2 are independent random variables; then, the relationship between them is: THE s 2 =E1 2 +E2 2 。 7. The method for determining the density and jump angle accuracy of a projectile system according to claim 3, characterized in that: The method for determining the density of the projectile system and the accuracy of the jump angle meets the following requirements: First, the number of components one (1) ejected by the standard ejector at one time is one or more; when the number of components one (1) is greater than one, the masses of different components one (1) are increased in sequence along the launching direction, with the muzzle of the ejector barrel being the front and the bottom of the ejector barrel being the back, that is, they are arranged in the order of large mass at the front and small mass at the back; Standard projectiles project composite projectiles that meet one of the following requirements: using chemical charges to propel the projectiles, or using non-chemical charges to propel the projectiles; Second, the launching power structure of the composite projectile meets the following requirements: ① For a rifled projectile that does not use chemical charges to propel the projectile; there is at least one component one (1); when the number of components one (1) is greater than 1, their masses increase in sequence along the launch direction; along the launch direction, the last individual of the composite projectile is provided with a launch power structure to provide power for all individuals in the entire composite projectile; ② For a rifled projectile that uses chemical charges to propel the projectile, a launch power module (3) is arranged on the last unit of the composite projectile; the launch power module (3) serves as a launch power to provide the chamber pressure and initial velocity necessary for launching the component 2 (2) and all components 1 (1) in the composite projectile; the launch power module (3) is composed of: a cartridge (3.1), a propellant (3.2), and a primer (3.3); wherein: the cartridge (3.1) is arranged at the rear end of the composite projectile, the propellant (3.2) is arranged in the inner cavity of the cartridge (3.1), and the primer (3.3) is arranged at the rear end of the cartridge (3.1); When the ejection system is a rifled standard projectile, when component one (1) is in front, the modification requirements of component two (2) are: ① remove the fuse and the oval part (2.1) of the warhead; ② retain all parts of the rear part of the standard projectile, namely the centering part (2.2), the cylindrical part (2.3) and the cylinder with the bullet belt and the tail part (2.5); ③ at the same time, the inner cavity of the rear part of the standard projectile is hollowed out; ④ and a head screw (2.6) is added behind component one (1) and in front of the first centering part, so that component one (1) does not enter the inner cavity of the centering part (2.2) at the rear of the standard projectile; ⑤ balance it and component one (1) so that their mass is equal to the mass of the original standard projectile; When the projectile system is a rifled standard projectile, when the component one (1) is at the rear, the modification requirements are: ① a cartridge (3.1) is added to the rear of the component one (1), and the cartridge (3.1) is modified or re-customized from the front end of the cartridge of the original standard projectile, i.e., the local structure near the end of the barrel mouth; the inner diameter of the cartridge (3.1) is required to be the same as the outer diameter of the tail (2.5) of the standard projectile; ② a bullet-blocking plate (3.4) is added to the rear of the composite projectile; or A bullet-blocking plate (3.4) is added to the cartridge case (3.1) behind the first component (1) to prevent the first component (1) and the second component (2) from colliding with each other and causing the chamber to explode; ③ when a buffer pad is added, the buffer pad and the first component (1) and the second component (2) are uniformly weighted so that the sum of their masses is equal to the mass of the original standard projectile; when a bullet-blocking plate (3.4) is added, the first component (1) and the second component (2) are uniformly weighted so that the sum of their masses is equal to the mass of the original standard projectile.

8. The method for determining the density and jump angle accuracy of a projectile system according to claim 7, characterized in that: When determining the accuracy of the projectile jump angle, the composite projectile meets the following requirements: in the composite projectile, component two (2) is located behind or in front of component one (1); the composite projectile is a composite structure using chemical charges as a launching power; the composite projectile is also provided with a launching power module (3), and the launching power module (3) is arranged at the rear of the composite projectile; First, when the ejection system is a smoothbore standard ejector and the second component (2) is behind the first component (1), the launching power module (3) is a part of the second component (2); the launching power module (3) is composed of a cartridge case (3.1), a propellant (3.2), and a primer (3.3); wherein: the cartridge case (3.1) is a closed space formed by the cooperation of the second component (2) and the inner cavity of the barrel (4); the propellant (3.2) is the propellant of the original structure of the second component (2); the primer (3.3) is the primer of the original structure of the second component (2), and is arranged at the rearmost part of the second component (2); Secondly, when the ejection system is a smoothbore ejector and the second component (2) is in front of the first component (1), the launch power module (3) is composed of the following: a cartridge (3.1), propellant (3.2), and a primer (3.3); wherein: the cartridge (3.1) is arranged behind the first component (1), the propellant (3.2) is arranged in the inner cavity of the cartridge (3.1), and the primer (3.3) is arranged at the rear end of the cartridge (3.1); For a smoothbore standard projectile, component two (2) is a part of a standard projectile or is modified from a standard projectile; the modification requirements are: component two (2) removes the standard projectile fuse and the warhead oval part (2.1), and retains the gas-sealing ring (2.7) and other parts of the standard projectile; the bottom of the tail pipe (2.9) is an impact-type or electric-fired primer (3.3); for a smoothbore standard projectile, the composite projectile used meets one of the following requirements: first, it is composed of at least one component one (1) and one component two (2); second, it is composed of a component two (2) that can seal the standard projectile gas and at least two components one (1); Third, for a standard projectile of a sub-caliber, the composite projectile component 2 (2) is modified from a standard projectile of a standard projectile, and the component 1 (1) in the composite projectile is used to replace the core in the cartridge of the standard projectile of the sub-caliber; before launching, the component 1 (1) is arranged inside the component 2 (2), and the launching power module (3) is served by the power structure of the original component 2 (2); the launching power module (3) is composed of: a cartridge (3.1), propellant (3.2), and a primer (3.3); wherein: the cartridge (3.1) is arranged at the rear of the component 2 (2), the propellant (3.2) is arranged in the inner cavity of the cartridge (3.1), and the primer (3.3) is arranged at the rear of the cartridge (3.1); Fourthly, for a projectile without a cartridge, its launch power module (3) is equivalent to that of a standard projectile; the specific requirements are: the additional charge of the propellant (3.2) is tied to the tail tube (2.9), and the primer (3.3) is at the bottom of the tail tube (2.9); when launching, the projectile slides down the barrel (4) of the standard projectile and hits the firing pin at the bottom of the barrel (4), the primer (3.3) ignites the propellant (3.2), and the gunpowder gas shoots the projectile out of the barrel (4).

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