Strong impact test method, system and test projectile for testing the soft recovery of a projectile body

Abstract

The application discloses a soft recovery test method and system for a strong impact test projectile body and a test projectile, and belongs to the field of strong impact test testing; the method is characterized in that: first, a high-speed camera is arranged on the side of the muzzle of a simulated artillery strong impact test device, and the lens of the high-speed camera is directed to the muzzle; an ultra-wide-angle camera is arranged on the rear side of the simulated artillery strong impact test device, and the lens of the ultra-wide-angle camera is directed to the front of the simulated artillery strong impact test device; then, the speed of the test projectile out of the muzzle and the real-time state and posture of the test projectile in the recovery process are acquired; finally, the damage reason and position of the tested sample are judged; the damage reason and position of the tested sample are obtained, that is, the damage is caused by the bore overload or the landing collision. The application solves the problems that, when the test projectile is subjected to strong impact overload test by a simulated artillery or a gas gun, the test projectile lacks a key state detection means and safe and reliable recovery judgment basis.

Description

Technical Field

[0001] This invention belongs to the field of high-impact testing, specifically relating to a soft recovery test method, system, and test projectile for a high-impact assessment test body simulating artillery firing. Background Technology

[0002] Currently, large-caliber artillery weapons are gradually developing towards intelligence, improving firing accuracy and damage effectiveness by adding guided warheads and intelligent monitoring modules inside the projectile. However, intelligent munitions often fail due to insufficient high-impact testing during the development or factory verification stages, leading to repeated design work, increased range testing, and extended testing cycles. Therefore, when conducting high-impact testing on intelligent munitions, to simulate the impact overload state of the projectile during firing in the barrel as closely as possible, simulated artillery is often used to test the critical components of the intelligent munition. During the experiment, the overload exceeds tens of thousands of grams, and the maximum speed reached exceeds 500 m / s. The recovery of the large-mass, high-kinetic-energy test projectile becomes a challenge. If it cannot be recovered safely and reliably, it will cause secondary damage to the tested modules inside the test projectile, rendering the high-impact test invalid.

[0003] Currently, when conducting high-impact overload tests on test projectiles using simulated artillery or gas cannons, large-mass, high-kinetic-energy test projectiles are usually recovered using a hard landing method. This recovery method can cause secondary overload damage to the onboard acquisition, storage, and testing system. Another method is to use a method that penetrates flexible materials for recovery. This method requires a very large buffer area and has high requirements for the buffer material, resulting in extremely high costs and low safety.

[0004] Therefore, a reliable and effective soft recovery test method is needed for the recovery of high-impact test projectiles fired in simulated artillery or gas cannons. Summary of the Invention

[0005] The technical problem to be solved:

[0006] To overcome the shortcomings of existing technologies, this invention provides a soft recovery test method, system, and test projectile for a high-impact test projectile simulating artillery firing. The method involves a simulated artillery high-impact test device that generates the required high-impact overload for the test projectile by launching the projectile with gunpowder or high-pressure gas. A high-speed camera captures image data of the projectile's muzzle flash, while an ultra-wide-angle camera records image data of the parachute-assisted recovery projectile from muzzle exit to landing. This data is used to determine whether the impact overload test meets the test overload requirements and the effectiveness of the soft recovery. This invention solves the problem of lacking key state detection methods and reliable recovery criteria when conducting high-impact overload tests on test projectiles using simulated artillery or gas cannons.

[0007] The technical solution of this invention is: a soft recovery test method for a projectile used in a high-impact test, the specific steps of which are as follows:

[0008] Step 1: Set up the image measurement system and install the test projectile;

[0009] A high-speed camera is set up to the side of the muzzle of the simulated artillery impact test device, with the lens pointed at the muzzle; an ultra-wide-angle camera is set up to the side and rear of the simulated artillery impact test device, with the lens pointed at the front of the simulated artillery impact test device.

[0010] The test projectile was installed inside the chamber of a simulated artillery high-impact test device. The test projectile was a parachute-damped and recoverable test projectile.

[0011] Step 2: Obtain the velocity of the test projectile ejected from the muzzle;

[0012] The simulated artillery impact test device was activated, and a high-speed camera was used to capture motion images of the test piece ejecting from the muzzle. The host computer processed and calculated the motion images to obtain the average velocity of the test piece ejecting from the muzzle.

[0013] Step 3: Obtain the real-time status and attitude of the test missile during its recovery process;

[0014] While activating the simulated artillery impact test device, an ultra-wide-angle camera was used to record image data of the test projectile flying out of the muzzle until it landed, and the opening state and attitude of the parachute-resistant recovery test projectile were analyzed.

[0015] Step 4: Determine the cause and location of damage to the test specimen;

[0016] First, the average velocity in step 2 is analyzed to obtain the maximum impact overload that the test projectile experiences in the barrel. This is then compared with the preset impact overload of the test specimen to determine whether the maximum impact overload meets the requirements of the test specimen.

[0017] Then, analyze the opening state and attitude of the parachute-assisted recovery test projectile recorded in step 3 to determine the soft recovery effect of the test projectile.

[0018] Finally, based on the results of the two assessments, the cause and location of the damage to the test specimen were determined, namely, it was caused by in-bore overload or impact upon landing.

[0019] A further technical solution of the present invention is: in step 1, two positioning marks are set on the test projectile along the axial direction, and the distance between the two positioning marks is 500mm.

[0020] A further technical solution of the present invention is: in step 1, the transverse optical axis of the high-speed camera is perpendicular to the barrel axis of the simulated artillery impact test device.

[0021] A further technical solution of the present invention is: in step 1, the shooting direction of the ultra-wide-angle camera is parallel to the barrel axis of the simulated artillery impact test device.

[0022] A further technical solution of the present invention is: the average velocity in step 2 is calculated by reading the displacement signal of the test projectile during the muzzle ejection process obtained by high-speed imaging, performing a differential operation on the displacement data of multiple consecutive frames of images, and obtaining the average velocity of the test projectile when it leaves the muzzle.

[0023] A further technical solution of the present invention is: in step 4, if it is determined that the maximum impact overload does not meet the requirements of the test specimen, then the damage to the test specimen is caused by the in-bore overload; if it is determined that the parachute-resistant recovery test projectile has not opened or its attitude is unstable, then the damage to the test specimen is caused by the landing collision.

[0024] A system for implementing a soft recovery test method for a high-impact test projectile includes a simulated artillery high-impact test device, a parachute-type recovery test projectile, a high-speed camera, an ultra-wide-angle camera, and a host computer. The high-speed camera is positioned to the side of the muzzle of the simulated artillery high-impact test device, with its lateral optical axis perpendicular to the barrel axis of the simulated artillery high-impact test device. The ultra-wide-angle camera is positioned to the side and rear of the simulated artillery high-impact test device, with its shooting direction parallel to the barrel axis of the simulated artillery high-impact test device. The host computer is connected to the high-speed camera and the ultra-wide-angle camera for acquiring image data and performing calculations.

[0025] A test projectile used in a soft recovery test method for a high-impact test projectile is a parachute-resistance recovery test projectile, comprising a projectile body, a recovery body and a deceleration parachute disposed therein, and the test specimen is installed inside the recovery body; the projectile body is a non-fixed, split-type projectile case, which is in a clamped state inside the gun barrel and splits immediately after flying out of the gun barrel to eliminate the constraint on the recovery body and deceleration parachute;

[0026] The recovery body and the deceleration parachute are connected by a coupling assembly, which buffers the end of the parachute's lines to the top of the recovery body.

[0027] A further technical solution of the present invention is: the coupling component includes a ring head screw, the top of which is a ring for tightening and fixing the end of the parachute rope, and the bottom end is a screw threadedly connected to the center of the top surface of the recovery body; it also includes a parachute rope laying track set on the outer surface of the recovery body, and each parachute rope is coupled to the corresponding track on the outer surface of the recovery body by adhesive bonding, for buffering when the deceleration parachute is deployed.

[0028] A further technical solution of the present invention is: multiple parachute rope layout tracks are evenly distributed along the circumference of the outer surface of the recyclable body, and the number and position of the parachute ropes correspond one-to-one with the number of parachute ropes; the parachute rope layout track is a serpentine track with reciprocating bends, the tail of the track connects to the end of the parachute rope, and the head of the track connects to the upper end of the parachute rope, so as to avoid the parachute ropes from getting tangled when the deceleration parachute is deployed.

[0029] A further technical solution of the present invention is: the projectile body is a three-lobed tile structure, that is, a cylindrical projectile shell made up of three arc plates, and its bottom end is encapsulated with a projectile base; the projectile base is connected to the projectile body by a trapezoidal buckle;

[0030] The projectile base is a stepped cylindrical bottom cover, with its small-diameter end inserted into the projectile body and its large-diameter end located on the outside of the projectile body. A ring-shaped nylon projectile belt is fitted on it. The nylon projectile belt is located between the outer end face of the projectile body and the stepped surface of the projectile base, serving as a buffer connection between the two and preventing the projectile body from separating before it has completely detached from the gun barrel.

[0031] Beneficial effects

[0032] The beneficial effects of this invention are as follows: This invention proposes a soft recovery test method for high-impact test projectiles simulating artillery firing. Based on a parachute-assisted recovery test projectile, it provides a reliable and effective soft recovery test method for high-impact test projectiles. High-speed photography is used to observe the state of the parachute-assisted recovery test projectile at the moment of ejection from the muzzle, obtaining the state of the test projectile at the muzzle and simultaneously obtaining the initial velocity of the ejected projectile. Compared to the onboard storage test method, this invention can, at a lower cost and with higher efficiency, determine the maximum impact overload the test projectile experiences in the barrel by analyzing the initial velocity of the ejected projectile, and determine whether the impact overload meets the requirements of the tested specimen. Simultaneously, an ultra-wide-angle camera is used to obtain the state of the test projectile from the muzzle until landing, analyzing the opening state of the parachute and the descent attitude of the parachute-assisted recovery test projectile to determine the soft recovery effect of the test projectile. This allows for accurate differentiation between damage to the tested specimen caused by in-barrel overload and landing impact.

[0033] This invention provides a parachute-damped recovery test projectile, which achieves lossless recovery of the projectile after launch through parachute damping. It features a simple structure, easy assembly and disassembly, is ready to use and install, occupies little space, and can be used for high-impact environment testing of artillery projectiles under various conditions. Addressing the limitations of small projectile size and limited internal space, this invention ensures the attitude stability of the recovered projectile through a coupling component without adding any parachute opening mechanism or buffer connection mechanism. This solves the problem of parachute rope entanglement and ensures reliable acquisition of parameters related to the high-impact environment of the projectile within the artillery barrel.

[0034] Preferably, the coupling component of the present invention adopts a ring-head screw connection method to realize a detachable connection between the deceleration parachute and the recovery body, which can ensure the stability of the flight attitude of the recovery body; the parachute lines are coupled to the surface of the recovery body on a set track by adhesive bonding. Under the action of the parachute tension, the parachute lines gradually overcome the adhesive force from the top and gradually separate from the recovery body, which plays a buffering role in the connection of the two rigid bodies and ensures that the parachute lines will not entangle and affect the attitude of the recovery body during release.

[0035] Preferably, an annular nylon band is provided between the outer end face of the projectile and the stepped surface of the projectile base, thereby reducing the impact force of the projectile base on the projectile body. Attached Figure Description

[0036] Figure 1 This is a schematic diagram of the structure and positioning mark installation of the umbrella-type recovery test projectile according to an embodiment of the present invention;

[0037] Figure 2 This is a schematic diagram of the on-site layout of the measurement system in an embodiment of the present invention;

[0038] Figure 3 This is a flowchart of the test method according to an embodiment of the present invention;

[0039] Figure 4 This is a schematic diagram of the deceleration parachute structure according to an embodiment of the present invention;

[0040] Explanation of reference numerals in the attached drawings: 1. Projectile body, 2. Recovery body, 3. Deceleration parachute, 3.1. Parachute canopy, 3.2. Parachute lines, 3.3. Ring head screw, 4. Nylon projectile belt, 5. Projectile base, 6. Simulated artillery high impact test device, 7. First black and yellow BMW circular mark, 8-Second black and yellow BMW circular mark, 9. Parachute-resistant recovery test projectile, 10. High-speed camera, 11. Ultra-wide-angle camera, 12. Computer, 13. High-speed camera field of view. Detailed Implementation

[0041] The embodiments described below with reference to the accompanying drawings are exemplary and intended to explain the invention, and should not be construed as limiting the invention.

[0042] This invention relates to a soft recovery test method, system, and test projectile for high-impact test projectiles fired in simulated artillery or gas cannons.

[0043] An embodiment of a soft recovery test method for a high-impact test projectile, the specific steps of which are as follows:

[0044] Step 1: Set up the image measurement system and install the test projectile;

[0045] A high-speed camera is set up on the side of the muzzle of the simulated artillery impact test device, with the lens aimed at the muzzle and its transverse optical axis perpendicular to the barrel axis of the simulated artillery impact test device; an ultra-wide-angle camera is set up on the side and rear of the simulated artillery impact test device, with the lens aimed at the front of the simulated artillery impact test device and its shooting direction parallel to the barrel axis of the simulated artillery impact test device.

[0046] The test projectile was installed inside the chamber of a simulated artillery high-impact test device. The test projectile was a parachute-damped and recoverable test projectile.

[0047] Step 2: Obtain the velocity of the test projectile ejected from the muzzle;

[0048] The simulated artillery impact test device was activated, and a high-speed camera was used to capture motion images of the test object ejected from the muzzle. The upper computer read the displacement data of multiple consecutive images, performed a differential, and obtained the average velocity of the test object ejected from the muzzle.

[0049] Step 3: Obtain the real-time status and attitude of the test missile during its recovery process;

[0050] While activating the simulated artillery impact test device, an ultra-wide-angle camera was used to record image data of the test projectile flying out of the muzzle until it landed, and the opening state and attitude of the parachute-resistant recovery test projectile were analyzed.

[0051] Step 4: Determine the cause and location of damage to the test specimen;

[0052] First, the average velocity in step 2 is analyzed to obtain the maximum impact overload that the test projectile experiences in the barrel. This is then compared with the preset impact overload of the test specimen to determine whether the maximum impact overload meets the requirements of the test specimen.

[0053] Then, analyze the opening state and attitude of the parachute-assisted recovery test projectile recorded in step 3 to determine the soft recovery effect of the test projectile.

[0054] Finally, based on the results of the two assessments, the cause and location of the damage to the test specimen were determined, namely, the damage was caused by in-bore overload or landing collision. If it was determined that the maximum impact overload it could withstand did not meet the requirements of the test specimen, then the damage to the test specimen was caused by in-bore overload. If it was determined that the parachute-assisted recovery test projectile did not open or its attitude was unstable, then the damage to the test specimen was caused by landing collision.

[0055] Example 1 of a parachute-damped recovery test missile:

[0056] Reference Figure 1As shown, this embodiment of a parachute-damped recovery test projectile includes a projectile body 1, a recovery body 2, a deceleration parachute 3, a nylon cartridge belt 4, and a projectile base 5. The projectile body 1 has a three-lobed tile structure, that is, a cylindrical cartridge case spliced ​​together by three arc plates, with the projectile base 5 encapsulated at its bottom end. The projectile base 5 is connected to the projectile body by a trapezoidal buckle. The projectile base 5 is a stepped cylindrical bottom cover, with its small-diameter end inserted into the projectile body and its large-diameter end located on the outside of the projectile body. An annular nylon cartridge belt 4 is fitted on it. The nylon cartridge belt 4 is located between the outer end face of the projectile body 1 and the stepped surface of the projectile base 5, and is used for buffer connection between the two. It can be pre-positioned by adhesive to prevent the projectile body from separating before it is completely detached from the gun barrel.

[0057] To obtain the accurate muzzle velocity of the test projectile through high-speed camera analysis, black and yellow checkered markings 7 and 8 were installed on the test projectile. The distance between the centers of the crosshairs of the two black and yellow checkered markings 7 and 8 was 500 mm, and they were arranged along the axis of the test projectile as tracking markers and scale rulers for high-speed camera image analysis.

[0058] The recovery body 2 and the deceleration parachute 3 are detachably connected, which facilitates disassembly after recovery; the test specimen is installed inside the recovery body 2.

[0059] Soft recycling process:

[0060] When the parachute-recovery test projectile 9 flew out of the barrel of the simulated artillery impact test device 6, the projectile 1 was rapidly separated from the recovery body 2 and the deceleration parachute 3 due to the aerodynamic drag at the front end. After the three-lobed structure of the projectile 1 opened, it deviated from the trajectory under the action of aerodynamic force and continued to fly to the side and forward. The deceleration parachute 3 was inflated and deployed under the action of aerodynamic force, and it decelerated and flew together with the recovery body 2 and landed without damage.

[0061] Example 2 of the parachute-damped recovery test missile:

[0062] Reference Figure 1 As shown, this embodiment of a parachute-damped recovery test projectile includes a projectile body 1, a recovery body 2, a deceleration parachute 3, a nylon cartridge belt 4, and a projectile base 5. The projectile body 1 has a three-lobed tile structure, that is, a cylindrical cartridge case spliced ​​together by three arc plates, with the projectile base 5 encapsulated at its bottom end. The projectile base 5 is connected to the projectile body by a trapezoidal buckle. The projectile base 5 is a stepped cylindrical bottom cover, with its small-diameter end inserted into the projectile body and its large-diameter end located on the outside of the projectile body. An annular nylon cartridge belt 4 is fitted on it. The nylon cartridge belt 4 is located between the outer end face of the projectile body 1 and the stepped surface of the projectile base 5, and is used for buffer connection between the two. It can be pre-positioned by adhesive to prevent the projectile body from separating before it is completely detached from the gun barrel.

[0063] To obtain the accurate muzzle velocity of the test projectile through high-speed camera analysis, black and yellow checkered markings 7 and 8 were installed on the test projectile. The distance between the centers of the crosshairs of the two black and yellow checkered markings 7 and 8 was 500 mm, and they were arranged along the axis of the test projectile as tracking markers and scale rulers for high-speed camera image analysis.

[0064] The recovery body 2 and the deceleration parachute 3 are detachably connected by a ring-head screw. The top of the ring-head screw is a circular ring for tightening and fixing the ends of the parachute lines, and the bottom is a screw threaded to the center of the top surface of the recovery body. The outer surface of the recovery body 2 has parachute line layout tracks. Each parachute line 3.2 is adhesively attached to the corresponding track on the outer surface of the recovery body 2 for cushioning during parachute deployment. Multiple parachute line layout tracks are evenly distributed circumferentially on the outer surface of the recovery body 2, corresponding one-to-one with the number and position of the parachute lines. The parachute line layout tracks are serpentine tracks with reciprocating bends, the tail of the track connecting to the end of the parachute line, and the head of the track connecting to the upper end of the parachute line, to prevent the parachute lines from tangling during deployment. The test specimen is installed inside the recovery body 2.

[0065] Soft recycling process:

[0066] When the parachute-recovery test projectile 9 flew out of the barrel of the simulated artillery impact test device 6, the projectile 1 was rapidly separated from the recovery body 2 and the deceleration parachute 3 due to the aerodynamic drag at the front end. After the three-lobed structure of the projectile 1 opened, it deviated from the trajectory under the action of aerodynamic force and continued to fly to the side and forward. The deceleration parachute 3 was inflated and deployed under the action of aerodynamic force, and it decelerated and flew together with the recovery body 2 and landed without damage.

[0067] The parachute-damped recovery test projectile in the above two embodiments is used in the implementation system of a soft recovery test method for a high-impact test projectile. The implementation system includes a simulated artillery high-impact test device 6, a parachute-damped recovery test projectile 9, a high-speed camera 10, an ultra-wide-angle camera 11, and a computer (i.e., a host computer) 12. The high-speed camera 10 is located to the side of the muzzle of the simulated artillery high-impact test device 6, and its transverse optical axis is perpendicular to the barrel axis of the simulated artillery high-impact test device 6. The ultra-wide-angle camera 11 is located to the side and rear of the simulated artillery high-impact test device 6, and its shooting direction is parallel to the barrel axis of the simulated artillery high-impact test device 6. The computer 12 is connected to the high-speed camera 10 and the ultra-wide-angle camera 11 and is used to acquire image data and perform calculations.

[0068] Reference Figure 2As shown in the diagram, this embodiment illustrates the equipment setup for the high-impact test. The parachute-assisted recovery test projectile 9 is launched from the muzzle of the simulated artillery high-impact test device 6. A high-speed camera 10 captures motion images of the parachute-assisted recovery test projectile 9 at the moment of exiting the muzzle. A computer 12 processes these motion images to obtain the projectile's displacement data. Before the parachute-assisted recovery test projectile 9 lands, an ultra-wide-angle camera 11 captures images of the projectile 9 to obtain its deceleration parachute opening status and attitude during flight.

[0069] Reference Figure 3 As shown, the specific test method in this embodiment is as follows: First, two black and yellow grid marks are arranged along the axis of the parachute-resistant recovery test projectile, with a distance of 500mm between the centers of the two marks; second, a high-speed camera is mounted on the side of the simulated artillery impact test device, with the lateral optical axis of the high-speed camera perpendicular to the axis of the simulated artillery impact test device barrel, ensuring that the camera's field of view is approximately 2000mm, the image resolution is 1mm / pixel, the barrel occupies approximately 500mm in the frame, and the frame rate is set to 10000fps; furthermore, an ultra-wide-angle camera is mounted on the side of the simulated artillery impact test device. The camera was positioned parallel to the barrel axis. Further, an impact overload test was conducted using a simulated artillery impact test device, launching a parachute-assisted recovery test projectile. A high-speed camera recorded the image data of the parachute-assisted recovery projectile the moment it exited the muzzle, while an ultra-wide-angle camera recorded the image data from its exit to its landing. The computer processed the displacement signal of the parachute-assisted recovery projectile upon exiting the muzzle, and the muzzle velocity was obtained through a first derivative. Finally, the image data recorded by the ultra-wide-angle camera was analyzed to determine whether the parachute-assisted recovery projectile deployed its deceleration parachute normally in the air and whether it landed slowly and vertically. This analysis determined whether the impact overload test met the test overload requirements and the soft recovery effect.

[0070] Although embodiments of the present invention have been shown and described above, it is understood that the above embodiments are exemplary and should not be construed as limiting the present invention. Those skilled in the art can make changes, modifications, substitutions and variations to the above embodiments within the scope of the present invention without departing from the principles and spirit of the present invention.

Claims

1. A soft recovery test method for a hard impact qualification test projectile body, characterized by: The specific steps are as follows: Step 1: Set up the image measurement system and install the test projectile; A high-speed camera is mounted on the side of the muzzle of the simulated artillery impact test device, with the lens pointed at the muzzle; an ultra-wide-angle camera is mounted on the side and rear of the simulated artillery impact test device, with the lens pointed at the front of the simulated artillery impact test device; the horizontal optical axis of the high-speed camera is perpendicular to the barrel axis of the simulated artillery impact test device; the shooting direction of the ultra-wide-angle camera is parallel to the barrel axis of the simulated artillery impact test device. The test projectile was installed inside the chamber of a simulated artillery high-impact test device. The test projectile was a parachute-damped and recoverable test projectile. Two positioning marks were set along the axial direction on the test projectile, with a distance of 500 mm between the two positioning marks; Step 2: Obtain the velocity of the test projectile ejected from the muzzle; The simulated artillery impact test device was activated, and a high-speed camera was used to capture motion images of the test piece ejecting from the muzzle. The host computer processed and calculated the motion images to obtain the average velocity of the test piece ejecting from the muzzle. Step 3: Obtain the real-time status and attitude of the test missile during its recovery process; While activating the simulated artillery impact test device, an ultra-wide-angle camera was used to record image data of the test projectile flying out of the muzzle until it landed, and the opening state and attitude of the parachute-resistant recovery test projectile were analyzed. Step 4: Determine the cause and location of damage to the test specimen; First, the average velocity in step 2 is analyzed to obtain the maximum impact overload that the test projectile experiences in the barrel. This is then compared with the preset impact overload of the test specimen to determine whether the maximum impact overload meets the requirements of the test specimen. Then, analyze the opening state and attitude of the parachute-resistant recovery test projectile recorded in step 3 to determine the soft recovery effect of the test projectile. Finally, based on the results of the two judgments, the cause and location of the damage to the test specimen were determined, namely, it was caused by in-bore overload or impact upon landing. The test projectile includes a projectile body, a recovery body and a deceleration parachute disposed therein, and the test specimen is installed inside the recovery body; the projectile body is a non-fixed, split-type projectile casing, which is in a clamped state inside the gun barrel and splits immediately after flying out of the gun barrel to eliminate the constraint on the recovery body and deceleration parachute; the recovery body and deceleration parachute are connected by a coupling component, which buffers the end of the deceleration parachute's parachute ropes to the top of the recovery body. The coupling assembly includes a ring head screw, the top of which is a ring for tightening and fixing the end of the parachute rope, and the bottom of which is a screw threaded to the center of the top surface of the recovery body; it also includes a parachute rope laying track set on the outer surface of the recovery body, and each parachute rope is coupled to the corresponding track on the outer surface of the recovery body by adhesive bonding, which is used for buffering when the deceleration parachute is deployed. The outer surface of the retractable body is evenly distributed with multiple parachute rope layout tracks along the circumference, and each track corresponds to the number and position of the parachute ropes. The parachute rope layout tracks are serpentine tracks with reciprocating bends, with the tail end of the track connecting to the end of the parachute rope and the head end connecting to the upper end of the parachute rope, in order to prevent the parachute ropes from getting tangled when the deceleration parachute is deployed. The projectile body has a three-lobed structure, that is, a cylindrical shell composed of three arc plates spliced ​​together, with a base encapsulated at its bottom. The base is connected to the projectile body by a trapezoidal buckle. The base is a stepped cylindrical bottom cover, with its small-diameter end inserted into the projectile body and its large-diameter end located on the outside of the projectile body. A ring-shaped nylon belt is fitted on it. The nylon belt is located between the outer end face of the projectile body and the stepped surface of the base, serving as a buffer connection between the two and preventing the projectile body from separating before it has completely detached from the gun barrel.

2. The soft recovery test method for a strong impact test projectile body according to claim 1, characterized in that: The average velocity in step 2 is calculated by reading the displacement signal of the test projectile during the muzzle ejection process obtained by high-speed camera, performing a differential on the displacement data of multiple consecutive frames of images, and obtaining the average velocity of the test projectile when it leaves the muzzle.

3. The soft recovery test method for a hard impact test projectile body according to claim 1, characterized in that: In step 4, if it is determined that the maximum impact overload does not meet the requirements of the test specimen, then the damage to the test specimen is caused by the in-bore overload; if it is determined that the parachute-type recovery test projectile has not opened or its attitude is unstable, then the damage to the test specimen is caused by the landing collision.

Images