Flexible belt net protection system for intercepting bullet with trigger fuze and explosion inducing method

Abstract

The invention relates to a flexible belt net protection system for intercepting a bullet with a trigger fuze and an explosion inducing method. Comprising a flexible belt net assembly, a detection system, a fire control system and a launching device, the flexible belt net assembly is assembled in the launching device, and the launching device is provided with the detection system and the fire control system; the launching device is assembled at the top of the protective fortification, and the flexible belt net assembly is composed of a flexible belt net body and mass blocks at all corner points of the flexible belt net; after the flexible belt net protection system is launched, the mass block pulls the flexible belt net body to be unfolded, the flexible belt net body makes physical contact with a bullet, and force conforming to a fuse triggering mechanism is generated; axial impact force, radial binding force and circumferential torque generated by the flexible belt net main body on an incoming target, namely an incoming bullet, cooperate with one another, so that a fuse is triggered. The net body unfolding area is large, the interception probability is high, parcel type protection reduces incidental damage, the device is suitable for urban civil scenes, and an efficient, safe and economic scheme is provided for active protection.

Description

Technical Field

[0001] This invention belongs to the field of active protection, specifically relating to a flexible mesh protection system and detonation method for intercepting projectiles with trigger fuses. Background Technology

[0002] Current hard-kill active protection methods mostly rely on the fragmentation and shockwave generated by the explosion of interceptor munitions to destroy them. However, this method has significant drawbacks: the fragmentation and shockwave effect lasts only a few milliseconds, requiring extremely precise hits within a very short time. If, due to accuracy deviations or target evasion, a critical area is not hit, the incompletely destroyed munition will approach the armor with residual kinetic energy. Furthermore, the penetration capability of fragments is limited by mass and velocity. If the fragment penetration depth is insufficient to penetrate the munition casing and detonate the internal explosive, ballistic deviation may cause the incoming munition to impact the armor at an unpredictable angle, thereby increasing the complexity and risk of defense. Summary of the Invention

[0003] The purpose of this invention is to provide a flexible mesh protection system and detonation method for intercepting projectiles with trigger fuses.

[0004] The technical solution to achieve the purpose of this invention is as follows: a flexible net protection system for intercepting missiles with trigger fuses, comprising a flexible net assembly, a detection system, a fire control system, and a launching device. The flexible net assembly is assembled inside the launching device, which is equipped with the detection system and the fire control system. The launching device is assembled on the top of the protective fortification. The flexible net assembly consists of a flexible net body and mass blocks at each corner of the flexible net.

[0005] After the flexible net protection system is launched, the mass block pulls the flexible net body to unfold, and the flexible net body makes physical contact with the warhead, generating a force that conforms to the fuze triggering mechanism; the axial impact force, radial restraint force and circumferential torque generated by the flexible net body on the incoming target, i.e., the incoming projectile, work together to effectively trigger the fuze.

[0006] Furthermore, the flexible mesh is polygonal, and the total mass of the protective system of the mass blocks is 1-1.5 times the mass of the flexible mesh itself;

[0007] The flexible belt mesh is formed by weaving strip fabrics in a horizontal and vertical interlacing manner; the interlacing of the strip fabrics forms mesh holes, and the mesh area accounts for 20%-40% of the total area of ​​the flexible belt mesh;

[0008] The flexible mesh belt is made of fabric with a tensile strength between 400MPa and 1000MPa.

[0009] An application of the above-mentioned flexible mesh protection system is characterized in that the triggering threshold of the triggering fuse is a projectile of 100g-200g, where g is the gravitational acceleration, and the projectile has a built-in load sensing component.

[0010] A method for intercepting detonated projectiles with trigger fuses using the aforementioned flexible mesh protection system includes the following steps:

[0011] Step (1): Set up a flexible mesh protection system;

[0012] Step (2) The detection system identifies the flight trajectory and motion parameters of the incoming missile;

[0013] Step (3): The fire control system calculates the launch velocity of the flexible strip net;

[0014] Step (4): The launching device launches the flexible net assembly according to the launch speed of the flexible net calculated in step (3);

[0015] Step (5): The collision between the flexible mesh assembly and the incoming projectile decelerates the projectile and causes initial damage to the external protective structure of the projectile's trigger fuse; the dynamic load reaches the fuse trigger threshold, realizing the detonation of the incoming projectile; the mass block relies on inertia to drive the flexible mesh body to close, completely wrapping and binding the solid fragments generated by the explosion.

[0016] Furthermore, step (2) identifies the flight trajectory and motion parameters of the incoming projectile, including the projectile mass m2, the projectile flight speed v2, the angle α between the projectile flight direction and the horizontal direction, the horizontal distance L between the launching device and the collision position, and the launch angle θ of the flexible net.

[0017] Furthermore, step (3) specifically involves:

[0018] Let the horizontal direction of the incoming projectile's flight be the positive x-axis, and the direction of gravity be the positive y-axis. Analyze the horizontal collision velocity of the incoming projectile:

[0019] =130×cos8=128.5 m / s (1)

[0020] Calculate the impact force F based on the fuze overload relationship:

[0021] (2)

[0022] (3)

[0023] Among them, a f k is the overload threshold of the fuze. t With a load attenuation coefficient of 0.15, k i a is the inertial amplification factor. b For projectile acceleration;

[0024] Combining the relationship between collision impulse and momentum change, we get:

[0025] (4)

[0026] Among them, v a The velocity of the flexible net and the incoming projectile is the same, and t is the collision time.

[0027] Momentum conservation equation:

[0028] (5)

[0029] The velocity component along the x-axis at the instant of collision with the flexible belt mesh;

[0030] (6)

[0031] Combining equations (5) and (6), we get v a Relationship with v1:

[0032] (7)

[0033] The velocity v1 of the flexible mesh at the time of collision is calculated by combining equations (4) and (7);

[0034] Using the air resistance formula, the acceleration caused by air resistance applied to the flexible mesh is obtained:

[0035] (8)

[0036] Among them, v x Let C be the horizontal velocity of the flexible belt net at time t. d The air resistance coefficient is 0.8, ρ is the air density, and S is the windward area of ​​the net after it is unfolded.

[0037] Will Substituting into equation (6) above, we get:

[0038] (9)

[0039] Separating variables yields:

[0040] (10)

[0041] Integrating both sides of the equations respectively, we get:

[0042] (11)

[0043] Where v ox For the horizontal launch velocity of the flexible network, we get:

[0044] (12)

[0045] Separating variables from equation (6), we get:

[0046] (13)

[0047] Integrating both sides of the equation, we get:

[0048] (14)

[0049] The calculation yields:

[0050] (15)

[0051] The flexible mesh is subjected to gravity and air resistance in the vertical direction, and its approximate horizontal average speed is...

[0052] (16)

[0053] The vertical launch velocity of the flexible strip net is derived as follows:

[0054] (17)

[0055] Calculate the flexible strip net launch velocity:

[0056] (18).

[0057] Compared with the prior art, the significant advantages of this invention are:

[0058] 1. The flexible mesh is woven from a polygonal structure and high-strength fabric, with an optimized mesh area ratio to balance interception effectiveness and air penetration. Driven by the kinetic energy of corner mass blocks, it can quickly deploy to form a large-area barrier. Simultaneously, the fire control system relies on a three-order algorithm of "associative modeling - coupling calculation - correction verification" to accurately calculate the launch velocity, ensuring that the dynamic load generated by the mesh collision meets the triggering fuze, significantly improving the interception success rate against various types of munitions with triggering fuzes.

[0059] 2. It innovatively adopts a wraparound interception and protection logic, employing a three-stage process of "collision deceleration and deflection - dynamic load detonation - wrapping and buffering." This not only detonates the munitions in advance but also restrains fragments through the mesh wrapping and weakens the shock wave through flexible buffering, fundamentally solving the secondary risks caused by fragmentation and trajectory deviation in traditional hard-kill protection. This feature makes it safe for application in scenarios with stringent requirements for collateral damage, such as urban civilian fortifications and densely populated areas.

[0060] 3. The lightweight design reduces the overall weight of the system, lowering the load on the launcher and the deployment threshold. Compared to hard-kill solutions that rely on high-precision interceptor missiles, this system has a simpler structure and lower manufacturing costs. Meanwhile, the modular, flexible net-band interceptor units facilitate rapid loading and replacement, significantly reducing operational and maintenance expenses and possessing economic advantages for long-term widespread application. Attached Figure Description

[0061] Figure 1 This is a schematic diagram illustrating the process of intercepting munitions with trigger fuses according to the present invention.

[0062] Explanation of reference numerals in the attached figures:

[0063] 1-Detection system, 2-Fire control system, 3-Launch device, 4-Flexible net, 5-Mass block, 6-Incoming munition, 7-Explosion fragments, 8-Shock wave. Detailed Implementation

[0064] This invention discloses a flexible mesh protection system and detonation method for intercepting munitions with trigger fuses. The process is as follows: a detection system monitors and identifies incoming munitions entering the protection range in real time, collecting key parameters such as velocity, mass, and flight direction, and transmitting them to the fire control system; the fire control system calculates the launch velocity required to trigger the fuse and issues a command. Based on this, a high-strength flexible mesh is released through a launching device, forming an interception barrier along the target trajectory to resist the impact of the munition and trigger the fuse in advance. The invention is further described below with reference to the accompanying drawings and embodiments.

[0065] This invention provides a flexible mesh protection system and detonation method for intercepting munitions with trigger fuses, comprising the following steps:

[0066] Step 1: The detection system monitors and accurately identifies incoming munitions in real time. After determining that the munition has entered the protection range, it quickly collects the velocity, mass, and flight direction parameters of the munition and transmits the parameters to the fire control system synchronously.

[0067] Step 2: After receiving the parameters, the fire control system performs comprehensive analysis and calculations on the data to accurately calculate the launch speed that meets the interception requirements. Subsequently, the fire control system issues the launch speed control command to the launching device.

[0068] Step 3: The launching device launches the flexible net interception unit to the preset target interception area according to the command. During the launch process, the mass blocks assembled at the corners of the flexible net acquire sufficient kinetic energy under the driving force of the launching device, thereby driving the flexible net to overcome air resistance and rapidly deploy within the preset interception area, ultimately forming a polygonal interception barrier that effectively intercepts incoming munitions.

[0069] Step 4: When the flexible net collides with the incoming target, the impact reaction force decelerates the incoming target and deflects its flight trajectory, thereby decelerating the incoming target and deflecting its flight trajectory. At the same time, the friction and local compression between the flexible net and the target surface cause initial damage to the surface, protruding structures and auxiliary components of the incoming target.

[0070] Step 5: The flexible mesh continuously impacts the surface of the incoming target and pulls and wraps around it as the target moves, forming a dynamic load through the interaction between the two. When this dynamic load is transferred to the fuse of the incoming target, the overload value borne by the fuse reaches its preset trigger threshold to achieve "detonation" (prematurely triggering the target fuse and detonating the target).

[0071] Step Six: The mass block uses its inertia after the collision to close the flexible mesh. The flexible mesh then wraps and binds the solid fragments generated from the disintegration. At the same time, the flexible mesh's buffering properties weaken the propagation intensity of the shock wave, preventing fragments from spreading and secondary damage caused by the shock wave.

[0072] The fire control system analyzes the detection system data using algorithmic logic. The specific process is as follows: First, establish a quantitative relationship between fuze overload and collision force, and then calculate the minimum collision force required for interception based on the known overload threshold of the incoming projectile fuze. Next, using the flight direction of the incoming projectile as a reference, calculate the velocity components of the projectile and the net separately, and solve for the minimum collision velocity required for the flexible net by combining the law of conservation of momentum. Considering environmental factors such as air resistance and gravity, derive the initial launch velocities of the net in the horizontal and vertical directions, and calculate the resultant launch velocity.

[0073] The flexible strip net interception unit includes a flexible strip net and mass blocks. The mass blocks are assembled at various corners of the flexible strip net, and the total mass of the mass blocks is approximately 1-1.5 times the mass of the flexible strip net itself. This mass ratio design ensures both the overall lightweight design of the interception system and that the mass blocks have sufficient kinetic energy to pull the flexible strip net to deploy stably.

[0074] The flexible mesh has a polygonal structure, woven from strips of fabric in a horizontal and vertical interlacing pattern. The interlacing of the strips forms mesh openings, with these openings accounting for 20%-40% of the total area of ​​the flexible mesh. This mesh structure design and area ratio ensures, on the one hand, that the flexible mesh effectively intercepts incoming targets, preventing them from penetrating the mesh; on the other hand, it gives the flexible mesh good air permeability, reducing air resistance during deployment and ensuring the mesh quickly and stably forms within the pre-set interception area.

[0075] The flexible belt mesh is made of high-strength fabric with a tensile strength between 400MPa and 1000MPa to ensure the structural strength and cushioning performance of the flexible belt mesh.

[0076] The core principle of flexible mesh detonation is that the force conforming to the fuse triggering mechanism is transmitted through the physical contact between the mesh and the warhead; and the axial impact force, radial binding force and circumferential torque generated by the flexible mesh on the incoming target work together to effectively increase the fuse overload value and ensure stable and effective fuse triggering.

[0077] The incoming target is ammunition equipped with a trigger fuse, including but not limited to artillery shells, rockets, and grenades; the trigger fuse has a trigger threshold of 100g-200g (g is the acceleration due to gravity, 1g≈9.8m / s²), and has a built-in load sensing component that can accurately detect externally applied dynamic loads; when the external load reaches the preset trigger threshold of the fuse, the internal ignition sequence of the fuse is activated, thereby detonating the incoming ammunition.

[0078] Example

[0079] like Figure 1 As shown, the specific implementation method is as follows:

[0080] (1) Selection and assembly of interception components

[0081] Hexagonal high-strength flexible mesh 4 is selected, with a mesh body mass of m. 网 =1.5 kg, with 5 mass blocks assembled at each of the 6 corners of the net, and a total mass m 块 =2 kg, therefore the mass of the flexible strip net interception unit is m1=m 网 +m 块 =3.5 kg. The net is woven from strip fabric with a tensile strength of 600 MPa, and the mesh area is 30% of the total area of ​​the flexible net, ensuring both effective interception of incoming targets and good air penetration to reduce deployment drag. The net is installed on the launching device 3, and the launching device 3 is fixedly installed on the top of the civilian protective fortification.

[0082] (2) Detection system identifies key parameters

[0083] The detection system 1 and fire control system 2 are activated simultaneously. The detection system tracks the flight trajectory and motion parameters of the incoming rocket 6 in real time: the incoming rocket mass m2=4 kg, the flight speed v2=130 m / s, the angle α between the flight direction and the horizontal direction α=8°, the horizontal distance L between the launch device and the collision position L=30 m, and the launch angle θ of the flexible net θ=10°. The parameters are then transmitted to the fire control system in a synchronized manner.

[0084] (3) Fire control system calculation and analysis

[0085] The fire control system derives and calculates the key parameters of the flexible wire mesh required to meet the fuse triggering conditions based on the detection data, as follows:

[0086] Assuming the horizontal direction of the projectile's flight is the positive x-axis and the direction of gravity is the positive y-axis, analyze the horizontal collision velocity of the incoming projectile:

[0087] =130×cos8=128.5 m / s(1)

[0088] Calculate the impact force based on the fuze overload relationship:

[0089] (2)

[0090] (3)

[0091] Among them, the overload threshold a of the fuze f It is 150 g (g=9.8m / s) 2 (where k is the gravitational acceleration) and the load attenuation coefficient k t =0.15, inertial amplification factor k i =1.1, a b Given the projectile acceleration, m2 = 4 kg, the required collision force is calculated to be approximately 35294 N.

[0092] Combining the relationship between collision impulse and momentum change, we get:

[0093] (4)

[0094] Among them, v a Assuming the flexible netting and the incoming projectile share the same velocity, the collision time is t = 0.005 s.

[0095] Momentum conservation equation:

[0096] (5)

[0097] And the velocity component along the x-axis at the instant of collision with the flexible mesh;

[0098] (6)

[0099] Combining (5) and (6), we get v a Relationship with v1:

[0100] (7)

[0101] By combining (4) and (7), the velocity of the flexible mesh at the time of collision is calculated to be v1 = -34 m / s.

[0102] Using the air resistance formula, the acceleration caused by air resistance applied to the flexible mesh is obtained:

[0103] (8)

[0104] Among them, v x Let t be the horizontal velocity of the flexible belt net, and C be the air drag coefficient. d =0.8, air density ρ=1.2kg / m³ 3 The windward area of ​​the net after it is unfolded is S=0.2m². 2 .

[0105] Will Substituting into equation (6) above, we get

[0106] (9)

[0107] Separating variables

[0108] (10)

[0109] Integrating both sides of the equations respectively, we get

[0110] (11)

[0111] Where v ox For the horizontal launch speed of the flexible network, the following is compiled:

[0112] (12)

[0113] Where L = 30 m, we can solve for v. 0x =-76.43m / s

[0114] Separating variables from equation (6) yields

[0115] (13)

[0116] Integrating both sides of the equation, we get

[0117] (14)

[0118] Calculated

[0119] =0.609s(15)

[0120] The flexible mesh is subjected to gravity and air resistance in the vertical direction, and its approximate horizontal average speed is...

[0121] (16)

[0122] The vertical launch velocity of the flexible strip net is derived as follows:

[0123] 25.19 m / s(17)

[0124] Calculate the flexible strip net launch velocity:

[0125] 80.47 m / s(18)

[0126] 3) Net launch and deployment

[0127] The launching device launches the flexible mesh to the preset area at a speed of 81 m / s (higher than v0 to ensure stable detonation). Under the action of kinetic energy, the mass block drives the mesh to rapidly unfold, overcoming air resistance to form an interception barrier with an area of ​​approximately 1 m².

[0128] 4) Collision deceleration and initial damage

[0129] After the flexible net collided with the rocket, the impact reaction force slowed down the projectile. The trajectory deviation of the projectile was calculated to be 0.8 m according to the momentum conservation equation. At the same time, the friction and compression between the net and the surface of the projectile caused initial damage to the external protective structure of the projectile fuse.

[0130] 5) Dynamic load and detonation triggering

[0131] The net continuously impacts the surface of the projectile, generating pulling and entanglement effects. The axial impact force, radial binding force, and circumferential torque work together to form a dynamic load. After transmission, the fuze overload value reaches the trigger threshold of 120 g, initiating the ignition sequence to achieve rocket detonation.

[0132] 6) Sealing protection and prevention of secondary damage

[0133] After the collision, the mass block relies on inertia to drive the flexible net to close, completely wrapping and binding the solid fragments 7 generated by the explosion. At the same time, the flexible buffering characteristics of the net weaken the propagation intensity of the shock wave 8 by more than 55%, effectively preventing the fragments from spreading and the shock wave from causing secondary damage to the protective fortifications and surrounding civilian facilities.

Claims

1. A flexible belt net protection system for intercepting a flexible belt net with a triggered fuze projectile, characterized in that The flexible belt net protection system comprises a flexible belt net assembly, a detection system (1), a fire control system (2) and a launching device (3), the flexible belt net assembly is assembled in the launching device (3), the launching device (3) is provided with the detection system (1) and the fire control system (2); the launching device (3) is assembled on the top of a protective fortification, and the flexible belt net assembly is composed of a flexible belt net body (4) and mass blocks (5) at each corner point of the flexible belt net. After the flexible belt net protection system is launched, the mass blocks (5) pull the flexible belt net body (4) to be unfolded, the flexible belt net body (4) is in physical contact with a bullet, and a force meeting the trigger mechanism of a fuse is generated; the axial impact force, the radial binding force and the circumferential torque generated by the flexible belt net body (4) on an incoming target, i.e. an incoming bullet, are mutually coordinated, so that the fuse is effectively triggered.

2. The flexible web shield system of claim 1, wherein, The flexible belt net is a polygon, and the total mass of the mass blocks of the protection system is 1-1.5 times the mass of the flexible belt net itself. The flexible belt net is formed by weaving a strip-shaped fabric through horizontal and vertical interlacing; the interlaced part of the strip-shaped fabric forms a mesh hole, and the area of the mesh hole accounts for 20%-40% of the total area of the flexible belt net. The flexible belt net is made of a fabric with a tensile strength of 400-1000 MPa.

3. Use of a flexible belt webbing protection system according to any of claims 1-2, characterized in that, The trigger threshold for triggering the fuse is 100-200 g of the bullet, g is the acceleration of gravity, and the bullet is provided with a built-in load sensing assembly.

4. A method of intercepting a dud with a fuze train using the flexible belt netting protection system of claims 1-2, wherein, The method comprises the following steps: Step (1): setting the flexible belt net protection system; Step (2): the detection system (1) identifies the flight trajectory and motion parameters of the incoming bullet; Step (3): the fire control system (2) calculates the launching speed of the flexible belt net; Step (4): the launching device (3) launches the flexible belt net assembly according to the launching speed of the flexible belt net calculated in step (3); Step (5): the collision between the flexible belt net assembly and the incoming bullet slows down the bullet body, and causes the preliminary damage of the external protection structure of the bullet trigger fuse; the dynamic load reaches the trigger threshold of the fuse, so that the incoming bullet is induced to explode; the mass blocks drive the flexible belt net body to be closed by inertia, and fully wrap and bind the solid fragments generated by the explosion.

5. The method of claim 4, wherein, Step (2) identifies the flight trajectory and motion parameters of the incoming bullet, including the mass m2 of the incoming bullet, the flight speed v2 of the incoming bullet, the angle α between the flight direction of the incoming bullet and the horizontal direction, the horizontal distance L between the launching device and the collision position, and the launching angle θ of the flexible belt net.

6. The method of claim 5, wherein, Step (3) is specifically: It is assumed that the horizontal direction of the incoming bullet is the positive direction of the x-axis, and the direction of gravity is the positive direction of the y-axis, the horizontal collision speed of the incoming bullet body is analyzed: (1) According to the overload relationship of the fuse, the collision force F is calculated: (2) (3) where a f is the overload threshold of the fuze, k t is the load attenuation coefficient = 0.15, k i is the inertial amplification coefficient, a b is the projectile acceleration; Combined with the collision impulse and the momentum change relationship, it is obtained that: (4) where v a is the common velocity of the flexible belt web and the incoming projectile, and t is the duration of the impact. The momentum conservation equation is: (5) The velocity component of the flexible belt net in the x-axis at the moment of collision is: (6) Simultaneous equations (5) (6) give v a v1relationship: (7) The velocity v1 of the flexible belt net at the moment of collision is calculated by combining equations (4) and (7); Combined with the air resistance formula, the acceleration of the air resistance applied to the flexible belt net is obtained: (8) where v x is the horizontal velocity of the flexible web at time t, C d is the air resistance coefficient = 0.8, p is the air density, and S is the windward area of the web after it is deployed. Will Substituting into equation (6) above, we get: (9) The variable is separated to obtain: (10) The integral of both sides of the equation is: (11) where v ox is the horizontal launch velocity of the flexible net, and we obtain (12) The variable is separated from equation (6) to obtain: (13) The integral of both sides of the equation is: (14) The calculation result is: (15) The approximate horizontal average speed of the flexible belt net in the vertical direction is subjected to the gravity and the air resistance, and is (16) The vertical launching speed of the flexible belt net is derived as (17) The launching speed of the flexible belt net is obtained as (18)。

Images