Triggered fuze impact target overload and firing pin dynamic characteristic comprehensive test system and method

Abstract

This invention discloses a comprehensive testing system and method for the overload and firing pin dynamic characteristics of a trigger fuze upon impact with a target. Without altering the original physical parameters of the fuze, such as its mass and moment of inertia, this invention modifies the fuze by incorporating a firing pin dynamic characteristic acquisition device and a fuze overload testing device. This allows for the simultaneous acquisition of overload parameters during the entire ballistic flight of the munition and the firing pin dynamic characteristic parameters during target impact. The system precisely quantifies the correspondence between "overload - firing pin dynamic characteristics - ignition result," reflecting real-world operating conditions and clarifying the influence weight of each parameter on misfires. This comprehensive evaluation of the fuze's instantaneous firing rate, sensitivity, and ignition reliability provides data support for fuze structure optimization.

Description

Technical Field

[0001] This invention relates to the field of fuze performance testing technology, specifically to a comprehensive testing system and method for trigger fuze impact target overload and firing pin dynamic characteristics. Background Technology

[0002] The impact fuse is a core component that uses the reaction force or inertia of a projectile upon contact with a target to trigger the ignition mechanism, thus achieving the destructive function of the ammunition. It is also known as a "contact fuze" or "impact-detonation fuse." Due to its advantages such as low manufacturing cost, convenient operation, and strong environmental adaptability, the impact fuse is widely used by the armed forces of various countries in various types of ammunition and equipment.

[0003] In actual combat and training scenarios, the problem of misfires in fuses is a key hidden danger threatening combat effectiveness and operational safety. A misfire refers to a malfunction in which the fuse fails to ignite after the projectile impacts the target, resulting in the ammunition failing to detonate properly. Its harms are mainly manifested in three aspects: First, it directly affects combat effectiveness, as misfired ammunition cannot inflict effective damage, potentially missing crucial combat opportunities; second, it increases the risk of battlefield cleanup, as unexploded misfired ammunition left on the battlefield is easily exploited by the enemy or causes accidental casualties to civilians or friendly forces following behind; third, it affects equipment reliability assessment, as frequent misfires reduce the combat personnel's trust in the weapon system and interfere with tactical deployment decisions.

[0004] To address the aforementioned issues and improve the ignition rate of mechanically triggered fuses under extreme boundary conditions (such as small drop angles and low drop velocities) and uncertain target media (such as water surfaces, tidal flats, and soft soil), as well as to enhance the overall reliability of the fuse, it is necessary to optimize the structural design of the fuse's internal components, such as the firing pin, spring, and safety mechanism. This process relies on extensive testing to obtain parameters of the fuse's overload upon impact with the target and the dynamic response of the firing pin, in order to evaluate and verify the fuse's reliability.

[0005] However, the environmental excitations faced by a fuze throughout its entire ballistic trajectory are extremely complex, encompassing high overload impacts during launch, centrifugal forces and aerodynamic loads during flight, and instantaneous impact loads during target impact. Furthermore, the parameters affecting fuze ignition (such as impact velocity, angle, and target hardness) are numerous. Simultaneously, as a single-use product, the internal structure of a fuze is typically small (millimeter-level), placing stringent requirements on fuze testing systems: miniaturization (to fit within the confined space of the fuze), high overload resistance (withstanding impacts up to tens of thousands of grams), and low power consumption (ensuring power supply for the entire ballistic test). Currently, most fuze testing equipment is bulky, lacks sufficient overload resistance (unable to withstand the instantaneous high overloads during launch and target impact), or has high power consumption that makes it difficult to meet long-term testing needs. It cannot be embedded within the fuze to achieve multi-parameter acquisition under the entire ballistic environment, particularly failing to acquire dynamic data of the fuze triggering mechanism (such as the firing pin) under real-world conditions, thus hindering fuze ignition reliability assessment and structural optimization.

[0006] Existing indirect measurement methods using array gratings to measure the dynamic characteristics of the firing pin (firing moment, pin penetration velocity, acceleration, and firing pin energy) require two to three optical transmitters (semiconductor laser beams) and receivers (optical receivers) to be placed along the firing pin's path or inside the detonator. While optical transmitters can be miniaturized, optical receivers are relatively large and limited by their field of view. In narrow-distance measurement scenarios within the confined space inside the fuze, their resolution is insufficient, making it impossible to accurately capture the instantaneous dynamic parameters at the firing moment. This results in significant calculation errors for key indicators such as firing pin penetration velocity and firing energy, making it difficult to accurately determine the fuze's firing capability under extreme boundary conditions (small drop angle, low drop velocity), and failing to provide accurate data support for the analysis of misfires. Meanwhile, the reliability of fuze ignition is affected by multiple parameters throughout the entire ballistic process, including projectile launch, aerodynamic parameters of the flight trajectory, temperature parameters, and projectile motion parameters, as well as projectile motion parameters, fuze load, and firing pin dynamic characteristics during target impact. Furthermore, these parameters are coupled with each other (e.g., overload parameters during target impact directly affect the firing pin's motion state). Existing testing systems are mostly single-parameter testing devices (e.g., only measuring overload), unable to achieve simultaneous acquisition and data correlation of multiple parameters. This makes it impossible to clearly define the influence weight of each environmental parameter on fuze misfires, hindering targeted optimization of fuze structural design to improve ignition rate under extreme conditions.

[0007] Therefore, it is necessary to develop a comprehensive fuze testing system and supporting testing methods that meet the above conditions. This is of great practical significance for achieving accurate assessment of fuze ignition reliability under various conditions, effectively reducing the probability of misfires, and optimizing fuze structural design. Summary of the Invention

[0008] In view of this, the present invention provides a comprehensive testing system for the overload and dynamic characteristics of a trigger fuze hitting a target, including a firing pin dynamic characteristic acquisition device and a fuze overload testing device. It can simultaneously measure the acceleration of the trigger fuze, the firing moment of the firing pin, as well as the needle penetration speed, acceleration and firing pin energy, and can comprehensively evaluate the fuze's instantaneousness, sensitivity and firing reliability.

[0009] The present invention provides a comprehensive testing system for trigger fuze impact target overload and firing pin dynamic characteristics, comprising a firing pin dynamic characteristics acquisition device and a fuze overload testing device.

[0010] The firing pin dynamic characteristic acquisition device is installed in the rotor seat after the rotor has been removed. It includes a multi-layer circuit board, a conductive elastic metal sheet, and a support pad. The multi-layer circuit board is arranged at intervals along the firing pin movement direction, and each layer of the circuit board has a through hole for the firing pin to pass through. The conductive elastic metal sheet is installed at the through hole and is used to make contact and conduction when the firing pin passes through. The support pad is used to adjust the height of the multi-layer circuit board so that the contact point of the conductive elastic metal sheet of any middle layer of the multi-layer circuit board is on the same plane as the original detonator end face. The fuze overload testing device is installed in the shell of the detonator tube after the pyrotechnic components have been removed. It includes an accelerometer and a processor. The accelerometer senses the full-trajectory overload of the projectile. The processor monitors the overload value sensed by the accelerometer in real time. If the detected overload value is greater than or equal to a first set threshold, it starts storing the detected overload value until the detected overload value is less than a second set threshold, at which point it stops storing and generates an overload curve. On the other hand, it monitors the conduction status of the multilayer circuit board, calculates the firing pin speed and firing pin impact energy, and marks the firing pin triggering time and firing pin speed on the overload curve.

[0011] Preferably, the portion of the conductive elastic metal sheet that contacts the firing pin has a bent structure.

[0012] Preferably, the rotor seat is machined and modified: the original mounting chamber where the rotor is located in the rotor seat is enlarged and bored flat. The geometric center of the processed chamber, the axis of the rotor seat and the motion axis of the firing pin coincide, and the inner diameter of the chamber is completely matched with the outer diameter of the multilayer circuit board; the through hole of the multilayer circuit board is located at the geometric center of the circuit board.

[0013] Preferably, through holes are set on the multilayer circuit board at the corresponding eccentric positions according to the original rotor's eccentricity.

[0014] Ideally, if the internal space of the detonation tube housing is insufficient, it can be modified into an extended version using the same material. The inner diameter, outer diameter, and threaded connection interface of the extended housing are precisely matched with the original structure.

[0015] Preferably, the fuze overload testing device further includes a fixing frame for fixing the circuit board carrying the processor and signal conditioning module.

[0016] Preferably, the interior of the outer shell is filled with protective filler material.

[0017] Preferably, the processor uses two timers of different frequencies to monitor the overload value sensed by the accelerometer and the conduction status of the multilayer circuit board; wherein, the high-frequency timer 1 continuously monitors the conduction status of the multilayer circuit board, and the low-frequency timer 2 monitors the overload value; the timer 1 has a higher priority than the timer 2. When the processor detects an overload value greater than or equal to the first set threshold, the two timers align their data based on that moment.

[0018] A preferred approach is to employ negative delay technology, which, in addition to recording real-time overload data collected after the fuze overload is ≥ the first set threshold, also records historical overload data collected during a period of time before the fuze overload is ≥ the first set threshold, in order to ensure the data integrity of the overload curve.

[0019] The present invention also provides a comprehensive fuze testing method using the above-described testing system, comprising: S1, Modify the fuse to be tested, install the test system, and inject test parameters from the host computer; S2, after powering on the fuse equipped with the test system, install it onto the projectile, load it into the cannon, and fire it; S3, the processor makes a real-time judgment on the fuze overload sensed by the accelerometer. If the fuze overload reaches the first set threshold, it synchronously collects and records the level signal of the firing pin conducting each layer of conductive elastic metal sheet, as well as the overload value sensed by the accelerometer. S4, when the sensed fuse overload is less than the second set threshold, stop data acquisition and return to step 3 until the projectile hits the ground; S5, the processor aligns the time axis of the firing pin turn-on signal with the time axis of the fuze overload signal based on the time when the fuze overload reaches the first set threshold; calculates the relative acceleration, absolute acceleration and motion speed of the firing pin based on the spacing of the multi-layer circuit board and the time difference of the turn-on time; generates an overload curve by combining the acceleration data at the corresponding time, and marks the firing pin trigger time and the firing pin speed at this time on the overload curve; S6. Evaluate the ignition reliability of the fuze based on whether the firing pin speed meets the fuze ignition threshold and the impact of fuze overload on the firing pin speed; if a "missed" situation occurs, locate the cause through correlation data.

[0020] Beneficial effects: 1. This invention adopts an "embedded integrated design + high overload resistance packaging process" fuze overload test device construction scheme to replace traditional external or large-scale test equipment. It achieves miniaturization and adaptation by modifying the original detonation tube shell of the fuze, and forms a high-strength protective structure by curing epoxy resin potting compound, which can withstand tens of thousands of g instantaneous impacts. At the same time, it adopts a low-power power management strategy to meet the full ballistic endurance requirements, thus solving the problem of mismatch between the test system and the miniaturization, high overload resistance and low power consumption requirements of the fuze.

[0021] 2. This invention adopts a direct measurement method for the dynamic characteristics of the firing pin using a "miniature direct contact three-layer conductive elastic metal sheet + high-speed sampling" method, replacing the traditional indirect measurement method using an array grating. It can be adapted to the millimeter-level space inside the fuse and achieves microsecond-level triggering accuracy through timer interrupt capture. It can accurately record the moment when the firing pin pierces the detonator and the dynamic characteristic parameters of the firing pin, thus solving the problem of the contradiction between the size and accuracy of the dynamic characteristic measurement of the firing pin.

[0022] 3. This invention employs a multi-parameter synchronous acquisition and correlation analysis scheme of "dual independent timer synchronous timing + negative delay data storage algorithm" to replace the traditional single-parameter testing mode. The processor of the fuze overload testing device sets two independently operating timers: Timer 1 for the firing pin signal and Timer 2 for the fuze overload signal. The two timers are synchronized using the ADC sampling start count as a unified reference. Combined with negative delay technology, the overload curve is fully preserved, achieving synchronous acquisition and time axis alignment of fuze overload and firing pin dynamic characteristics. Ultimately, deep correlation of multiple parameters is achieved, solving the problems of asynchronous acquisition of multiple parameters and missing data correlation analysis.

[0023] 4. This invention can accurately quantify the correspondence between "overload-firing pin dynamic characteristics-ignition result", clarify the influence weight of each parameter on misfire, and provide data support for fuse structure optimization. Attached Figure Description

[0024] Figure 1 A comprehensive testing system for trigger fuse impact target overload and firing pin dynamic characteristics.

[0025] Among them, 1- firing pin dynamic characteristic acquisition device, 2- fuse overload test device; 3- host computer.

[0026] Figure 2 This is a device for acquiring dynamic characteristics of the firing pin.

[0027] Among them, 1-firing pin dynamic characteristic acquisition device, 101-firing pin, 102-safety system cover plate; 103-circuit board; 104-conductive elastic metal sheet; 105-support pad; 106-wire; 107-rotor seat Figure 3 This is a schematic diagram of a device for acquiring dynamic characteristics of a firing pin.

[0028] Among them, 1041, 1042, and 1043 are conductive elastic metal sheets; 1061, 1062, and 1063 are wires; 101 is a firing pin; and 203 is a processor.

[0029] Figure 4 This is a device for testing fuse overload.

[0030] Among them, 2-fuze overload test device, 201-wire, 202-circuit board; 203-processor; 204-fixed frame; 205-power module; 206-accelerometer; 207-shell; 208-data transmission interface; 209-protective filling material.

[0031] Figure 5 This is a hardware schematic.

[0032] Figure 6 This is a flowchart of the procedure for the fuse overload test device.

[0033] Figure 7 This is based on the principle of negative delay. Detailed Implementation

[0034] The present invention will now be described in detail with reference to the accompanying drawings and embodiments.

[0035] This invention provides a comprehensive testing system for the overload of a trigger fuse hitting a target and the dynamic characteristics of the firing pin.

[0036] The core of this invention is to solve the misfire problem in scenarios with small impact angles and weak targets (target media such as water, tidal flats, and deserts) (trigger fuse firing pin stabbing type, inertial mechanism forward thrust type, and dual-action triggering where the firing pin stabbes downwards and the inertial mechanism also thrusts forward).

[0037] This invention first analyzes the factors affecting the triggering of a misfire: (1) When the projectile grazes the ground at a small angle of impact, the fuse firing pin generally cannot directly pierce it. Instead, the inertial body (the rotor, rotor seat, and the needle-piercing detonator in the fuse) moves forward. Compared with a large angle of impact directly hitting the target, the normal overload peak value is lower and the duration is longer. Scenario 1: If the overload does not reach the overload threshold for the inertial body to overcome the spring resistance, the inertial body cannot move forward, resulting in a misfire.

[0038] Scenario 2: If the overload reaches the overload threshold for the inertial body to overcome the spring resistance, but the cumulative duration of the floor-scrubbing overload is too short, the inertial body can overcome the initial spring resistance and move forward, but the movement does not reach the firing pin, resulting in a misfire.

[0039] Scenario 3: The overload reaches the overload threshold of the inertial body overcoming the spring resistance, and the detonator on the inertial body can contact the firing pin, but the forward speed is insufficient, and the energy of the firing pin hitting the end face of the detonator is insufficient to ignite.

[0040] (2) When directly hitting the target, if the falling speed is low, the falling angle is small (not enough to rub the ground) or the target medium is a weak target (water, mudflats, desert, etc.), the firing pin can strike downwards, and the inertial body can carry the detonator forward. However, the speed at which the firing pin strikes the detonator (the relative speed between the firing pin and the inertial body) is low, and the striking energy is insufficient to detonate the detonator.

[0041] Analysis of factors influencing premature detonation of the fuse: Premature detonation of a trigger fuze refers to the phenomenon where the fuze detonates prematurely, and the warhead detonates before the projectile reaches its intended target or completes its normal ballistic trajectory. The detonation point is typically located on the ballistic curve. The main causes of premature detonation include: fuze misfires, and in external ballistic environments, excessive nutation angle of a high-spin projectile or abnormal forward overload excitation causing the firing pin to actuate unexpectedly and strike the detonator end face. Therefore, analyzing the environmental excitation characteristics during firing pin misfires is crucial for revealing the mechanism of premature detonation and improving the reliability of fuze triggering.

[0042] In summary, the normal reaction force of a projectile hitting a weak target at a small angle of impact is weak. The essence of a fuze misfire is the mismatch between the target impact overload parameters and the firing pin dynamic characteristics. Simply collecting fuze overload or firing pin dynamic characteristic parameters alone cannot clarify the relationship between the two—measuring overload alone cannot determine whether the firing pin has reached its designated position or whether the kinetic energy impacting the detonator is sufficient; measuring firing pin dynamic characteristics alone cannot confirm the overload conditions of the fuze under various conditions. Therefore, this invention modifies the fuze to be tested. Without changing the original physical parameters such as the fuze's mass and moment of inertia, a firing pin dynamic characteristic acquisition device and a fuze overload testing device are installed in the fuze. These devices simultaneously collect the overload parameters of the fuze during the entire ballistic flight of the projectile and the firing pin dynamic characteristic parameters during the target impact process. This accurately quantifies the correspondence between "overload - firing pin dynamic characteristics - firing result," reflecting real-world conditions, clarifying the influence weight of each parameter on misfires, and thus comprehensively evaluating the fuze's instantaneous firing rate, sensitivity, and firing reliability, providing data support for fuze structure optimization.

[0043] Therefore, the integrated testing system for the overload of the trigger fuse hitting the target and the dynamic characteristics of the firing pin of the present invention comprises three parts: (1) a firing pin dynamic characteristics acquisition device, which is installed on the firing pin movement path of the mechanical trigger fuse and is used to record the moment when the firing pin hits the detonator; (2) a fuse overload testing device, which is used to record the full ballistic overload of the projectile; and (3) a host computer, which sets the test parameters and reads / erases the data.

[0044] First, this invention modifies the fuze to be tested. The core objective of this modification is to create dedicated space for installing a firing pin dynamic characteristic acquisition device, while preserving all core structures (excluding the pyrotechnic components and rotor) without altering the original physical parameters such as the fuze's mass and moment of inertia, and ensuring that the firing pin's movement path is precisely aligned with the firing pin hole of the device. This guarantees that the test data reflects the actual operating conditions. The specific modification process is as follows: First, all pyrotechnic components (including the detonator and explosive charge built into the rotor) in the original fuze detonation sequence are removed. Then, the entire rotor mechanism is removed to fundamentally avoid the safety risk of accidental triggering of pyrotechnic components during testing. At the original locations of the firing pin and detonator, a fuze overload testing device with a high-g acceleration sensor as its core and a dynamic characteristic testing device for the firing pin in the ignition mechanism are installed. The original non-pyrotechnic core functional structures of the fuze are retained, including the fuze shell, rotor base, detonation tube shell, firing pin components, safety system cover plate, screw fixing components, etc. The original thread specifications of the fuze detonation tube shell, the original dimensions of the firing pin components, and the original screw hole positions of the safety system cover plate are used. All retained non-pyrotechnic core structures must maintain their original installation relationships to ensure that the key physical parameters and operating logic of the modified fuze, such as size, mass, and moment of inertia, are completely consistent with the original fuze.

[0045] Ensure that there is sufficient space inside the detonator housing to accommodate the fuze overload testing device components such as the processor, accelerometer, and power module. If the space inside the detonator housing is insufficient, it can be modified into an extended version. The material of the extended section should be consistent with that of the original detonator housing (such as high-strength alloy steel), and the inner diameter, outer diameter, and connection interface threads of the extended housing should be precisely matched with the original structure.

[0046] (1) Firing pin dynamic characteristic acquisition device The firing pin dynamic characteristic acquisition device is installed on the firing pin movement path of the mechanical trigger fuse, specifically on the rotor seat, i.e., at the original rotor location, such as... Figure 2 As shown, it includes a multilayer circuit board, a conductive elastic metal sheet, a support pad, a safety system cover, and wires, used to record the moment the firing pin strikes the detonator and to calculate the firing pin's movement speed.

[0047] The circuit boards are arranged at intervals along the firing pin's movement direction. Each circuit board has a through-hole at its center for the firing pin to pass through. Two conductive elastic metal sheets are symmetrically welded to both sides of the through-hole, extending to the centerline of the through-hole to ensure contact between the firing pin and the two conductive elastic metal sheets when passing through the through-hole. Under normal conditions, the two conductive elastic metal sheets do not contact each other, and the measurement circuit is in an open state. When the firing pin passes through the through-hole along its movement path, it contacts the two conductive elastic metal sheets, and the measurement circuit becomes conductive, generating an electrical signal. The firing pin stroke is a fixed parameter for each fuse. The firing pin activation time can be deduced by combining the conduction time difference and the distance between each circuit board. Preferably, the number of circuit boards stacked is ≥3 layers to ensure sufficient conductive elastic metal sheets along the firing pin's movement path to activate detection nodes, allowing for the calculation of the firing pin's average speed and acceleration. This further derives the firing pin kinetic energy (corresponding to sensitivity) and firing pin movement time (corresponding to instantaneity), improving accuracy and system redundancy. The spacing between adjacent circuit boards can be controlled by the circuit board thickness or the interval distance.

[0048] The conductive elastic metal sheet is made of a metal material with high conductivity and high elastic recovery, such as beryllium copper spring sheet, which has good conductivity, elasticity and high strength. The part of the conductive elastic metal sheet that contacts the firing pin is designed with a curved structure. Under the premise that the two conductive elastic metal sheets do not touch, the distance between them is minimized as much as possible to improve the sensitivity of the firing pin trigger signal, reduce time error and ensure accurate capture of signal changes at the moment of firing pin movement.

[0049] The support pad is mounted on the rotor seat, located below the multi-layer circuit board, and is used to accommodate the internal cavity of the rotor seat after the rotor and detonator have been removed, achieving precise spatial positioning of the circuit board. After the original rotor and detonator of the fuze are removed, the remaining height of the cavity is greater than the total thickness of the circuit board. The height of the circuit board needs to be adjusted using the support pad to support the entire circuit board to the target position. The multi-layer circuit board is positioned by interlayer stacking or annular spacers. The dimensions of the annular spacers must meet the following requirements: the inner diameter is not less than the diameter of the circuit board's through-hole (to avoid obstructing the firing pin's passage), and the outer diameter is not greater than the outer diameter of the conductive elastic metal sheet (to avoid blocking the conductive elastic metal sheet or interfering with electrical signal conduction). By adjusting the thickness of the support pads and annular shims, the following conditions are achieved: ① The conductive elastic metal contacts of the first circuit board are located outside the original detonator; ② The conductive elastic metal contacts of the last circuit board are located inside the original detonator; ③ The conductive elastic metal contacts of any intermediate circuit board are on the same plane as the end face of the original detonator (ensuring that the moment the firing pin conducts through this layer is consistent with the moment the firing pin strikes the end face of the original detonator). This ensures that the complete stroke of the firing pin precisely covers the monitoring range of each layer of conductive elastic metal sheets. Preferably, the conductive elastic metal contacts of the first circuit board are on the same plane as the initial position of the firing pin tip (ensuring accurate spatial reference for capturing the firing pin's activation moment). During installation, the overall height of the circuit board can be fine-tuned by increasing or decreasing the number of support pads and replacing them with insulating support pads of different thicknesses (such as acrylic sheets, or other insulating materials of the same specifications as the circuit board). This ensures that the conductive elastic metal contacts of the intermediate circuit boards are located at the middle node of the firing pin's stroke, cooperating with the first and last layers, and calculating the firing pin's movement speed and acceleration through the conduction time difference. Simultaneously, it is necessary to ensure close contact between the support pad and the circuit board and fuze housing to prevent circuit board misalignment under high overload conditions. Furthermore, the insulating properties of the support pad provide electrical isolation between the circuit board and the fuze housing, preventing signal interference. By adjusting the thickness of the support pad to match the starting position of the firing pin, it is ensured that the firing pin's movement path is precisely aligned with the through-holes on the circuit board.

[0050] In addition, since the original rotor is an eccentric cylindrical structure, its rotation center does not coincide with the geometric center of the rotor seat. The purpose is to achieve physical isolation of the detonation sequence through rotational misalignment, and only align with the firing pin path after the rotor is turned upright. For the test device of this invention, if the circuit board is directly replaced with the original rotor position, two major problems will be faced: (1) If the outer diameter of the circuit board is the same as that of the original rotor, the firing pin hole needs to be opened eccentrically to align the firing pin path. However, the huge centrifugal force generated when high-spin stability projectiles (such as grenades) fly will inevitably cause the conductive elastic metal sheet at the opening of the circuit board to have eccentric mass. The centrifugal force may cause the circuit board, which is only fixed by the side wall adhesive, to rotate and shift, eventually causing the firing pin hole and the firing pin to be misaligned, and data cannot be collected; (2) If the firing pin hole of the circuit board is opened in the center, and the rotor seat is not processed, the eccentric space of the original rotor seat will cause the firing pin and the hole to be misaligned, and the firing pin cannot pass through normally, and the test will fail. Therefore, this invention designs two modification schemes to adapt to different types of projectiles: Option 1 (Compatible with all types of projectiles, especially high-spin projectiles) Core idea: Modify the rotor base through machining to make the installation space concentric and simplify the positioning of the circuit board.

[0051] Specific operation: Using machining methods, the mounting chamber where the original rotor is located in the rotor seat is enlarged and bored to make the geometric center of the chamber completely coincide with the axis of the rotor seat (i.e. the firing pin movement axis), forming a concentric cylindrical chamber; at the same time, it is ensured that the inner diameter of the chamber is completely matched with the outer diameter of the multi-layer circuit board of the firing pin dynamic characteristic acquisition device.

[0052] Circuit board adaptation: The firing pin holes of the multi-layer circuit board are all opened at the geometric center. During installation, the circuit board assembly is directly embedded into the concentric rotor seat cavity. Precise alignment of the firing pin holes and firing pins can be achieved without additional positioning structures. The circuit board and the inner wall of the rotor seat are tightly bonded with strong adhesive. The centrifugal force of the high-spin projectile will not cause it to deviate, resulting in strong stability.

[0053] Option 2 (for fin-stabilized low-spin projectiles) The core idea is to maintain the original eccentric structure of the rotor base and achieve hole alignment by positioning and fixing it with a circuit board.

[0054] Specific operation: According to the original rotor's eccentricity, drill a firing pin hole on the multilayer circuit board at the corresponding eccentric position (the hole position is consistent with the center position of the detonator after the original rotor is straightened); at the same time, drill 3-4 screw holes evenly on the edge of the circuit board (the screw hole position avoids the conductive elastic metal sheet and signal transmission line), corresponding to the reserved hole position on the rotor seat (if there is no reserved hole position, it can be drilled by machining to ensure that the hole position does not damage the structural strength of the rotor seat).

[0055] Fixing method: After the circuit board assembly is placed into the rotor seat chamber, it is fastened to the rotor seat by screws passing through the screw holes of the circuit board, completely restricting the rotational freedom of the circuit board; after installation, the coaxiality of the firing pin hole and the firing pin needs to be checked to ensure that the firing pin can pass through smoothly and does not rub against the hole wall.

[0056] The safety system cover is fixed to the original structure of the fuze (such as the rotor seat). The original fuze safety system cover or a customized adapter cover can be used. It is fixed by fasteners (such as screws) to ensure the structural stability of the device under high overload conditions.

[0057] The wires transmit the electrical signals generated when the conductive elastic metal sheets on each layer of the circuit board are turned on to the fuze overload test device, ensuring the integrity and accuracy of the signal transmission.

[0058] Figure 2 This is a modified type of fuse. The original detonator was placed in the original rotor; here, the rotor is removed, and the original detonation sequence is replaced with a firing pin dynamic characteristic acquisition device. The firing pin dynamic characteristic acquisition device mainly consists of a firing pin 101, a multi-layer circuit board 103, a conductive elastic metal sheet 104, and wires 106. A safety system cover 102 and a support pad 105 provide support for the device. The support pad 105 is directly constructed from multiple stacked circuit boards, the same as those on circuit board 103. The multi-layer circuit board 103 has three layers. The principle of the firing pin dynamic characteristic acquisition device is as follows: Figure 3 As shown, when the firing pin is activated, it passes sequentially through three conductive elastic metal sheets (beryllium copper springs) 1041, 1042, and 1043. The part of the conductive elastic metal sheet that contacts the firing pin is slightly bent downwards, and the gap between the two conductive elastic metal sheets should be as small as possible when they are not in contact. When the firing pin moves, the three circuits are turned on sequentially, and the three signals are transmitted through three wires 1061, 1062, and 1063 to the 203 processor for recording and storage. Figure 3 In the diagram, T1, T2, and T3 represent the conduction times of the circuits containing the 1041, 1042, and 1043 conductive elastic metal sheets, S represents the spacing between the conductive elastic metal sheets, and a represents the relative acceleration of the striking pin and the rotor seat driving the entire detection device forward. When the firing mechanism is a double-action firing mechanism (the striking pin strikes downward and the rotor seat moves forward), the relative acceleration of the striking pin and the rotor seat during the piercing process is assumed to be uniform acceleration. The total stroke of the striking pin is X. Assuming that the striking pin undergoes uniform acceleration linear motion, the speed is derived using the conduction time difference between adjacent elastic elements and the layer spacing S.

[0059] Let: the conduction time of the first layer (1041) be T1, the conduction time of the second layer (1042) be T2, and the conduction time of the third layer (1043) be T3; the velocity of the firing pin when passing through the second layer is... v 2. The acceleration is a. The spacing between layers in a multilayer circuit board can be equal or unequal.

[0060] If the intervals between each layer are not equal, the interval between layers 1 and 2 is S12, and the interval between layers 2 and 3 is S23 (known); according to the formula for uniformly accelerated linear motion... : Floors 1-2: (1) (2) Floors 2-3: (3) (4) In uniformly accelerated motion, the velocity of the second layer near the midpoint of the displacement can be approximated by the average velocity over the entire process, and strictly satisfies the following: (5) Joint (2) (4) elimination v 2. Solve for the acceleration. : (6) If the contact spacing of each layer of conductive elastic metal sheet is equal, and S12=S23=S, then: (7) (8) The acupuncture energy is the kinetic energy of the needle, and the formula is: (m is the mass of the firing pin, which is known).

[0061] (2) Fuze overload test device The fuze overload testing device is used to record the acceleration load of the projectile throughout its entire trajectory from launch and flight to impact with the target. Its structure includes a shell, a fixed frame, an acceleration sensor, a processor, a circuit board, a power module, wires, and a data transmission interface. The outer shell is modified from the original detonation tube shell of the fuze. That is, the length or inner diameter of the original detonation tube shell is modified according to the internal component layout requirements, without the need to redesign a completely new shell. This maximizes the compatibility with the original installation structure of the fuze and reduces the amount of modification to the fuze.

[0062] The accelerometer is installed inside the housing. A high-G triaxial accelerometer is selected, and its range needs to cover the overload range of the entire trajectory of the projectile. During installation, it is ensured that one of the detection axes coincides with the projectile axis.

[0063] The processor, installed within the housing, employs a high-speed microprocessor or dedicated data processing chip. It receives electrical signals (firing trigger signals) from the firing pin dynamic characteristic acquisition device and acceleration signals from the accelerometer, performing functions such as signal filtering, timing analysis, and signal type conversion. Its main functions include data acquisition algorithms and storage. The processor's built-in data acquisition and storage logic workflow for the fuze overload testing device is as follows: Figure 6 As shown.

[0064] Before launch, after the system is powered on, the processor completes initialization and then enters a low-power waiting state for data acquisition. In this state, the processor operates in a time-division multiplexing manner using two timers of different frequencies: Firstly, a high-frequency timer continuously monitors the circuit conduction status of the firing pin dynamic characteristic acquisition device. If the circuit containing the conductive elastic metal sheet is detected to be closed (i.e., firing pin triggering), firing pin timer 1 is started to record the conduction time of each circuit layer and store the timing data in memory. If no circuit closure is detected, high-frequency monitoring continues. Secondly, a low-frequency timer 2 synchronously monitors the fuze overload value. When the monitored overload value is ≥ a first set threshold, the acquired data is stored in memory in real time. During storage, it continuously checks whether the overload value is < a second set threshold. If the overload value is < the second set threshold, the acquisition and storage of overload data stops, and the low-power state is restored, waiting for the next overload ≥ the first set threshold to acquire the fuze overload. The first and second set thresholds are generally set to tens of grams, sufficient to filter out overload noise generated during projectile loading. The first and second set thresholds can be the same or different values; if they are the same, the conditions for starting and stopping sampling are the same. If the threshold is set to a positive or negative value, only overload in a single direction on the detection axis can be collected. If the threshold is set to an absolute value, overload in both positive and negative directions on the detection axis can be collected (corresponding to target collision overload and launch overload). In this embodiment, both the first and second threshold values ​​are set to |50|g. 50g can generally filter out sensor noise and overload noise generated by projectile loading (such as the projectile sliding inside the barrel and closing the breech), without filtering out small excitations that are sufficient to disengage the safety mechanism or trigger the firing mechanism.

[0065] To obtain a more complete acceleration curve, positive or negative delay techniques can be used. In addition to recording real-time overload data collected after the fuze overload ≥ a first set threshold, historical overload data collected for a period of time before the fuze overload ≥ the first set threshold is also recorded. This embodiment uses negative delay technology, the principle of which is as follows: Figure 7As shown, the entire storage space is divided into two regions: a negative latency region and an overload acquisition region. After the system is powered on, before the fuze overload reaches or exceeds a first set overload threshold, cyclic sampling is performed in the negative latency region. The cyclic sampling data capacity of the negative latency region is ≥128 data points, which is set according to actual needs such as sampling rate and RAM storage size. The buffer of the negative latency region is filled before writing from the beginning. When the fuze overload reaches the first set threshold, writing begins from the address after the reserved data size of the negative latency region (i.e., the overload acquisition region) until the overload is < a second set threshold. The 128 data points of the negative latency region and the data of the overload acquisition region are written to the memory, and the system enters a low-power state waiting for acquisition.

[0066] To achieve synchronous correlation of parameters on the time axis, two timers, Timer 1 and Timer 2, are used in the processor while waiting for readings. Timer 1 is used for the firing pin dynamic characteristic acquisition device, and Timer 2 is used for the fuze overload testing device. Timer 1 has higher priority than Timer 2. The sampling frequency of the firing pin dynamic characteristic acquisition device is 500kHz, and the sampling frequency of the fuze load is 10kHz. The sampling frequency can be set according to the performance of the processor, ADC, and other hardware, combined with the requirements. Timer 1 and Timer 2 start synchronous timing from the reference point when the fuze overload exceeds the first set threshold acquired by the ADC. The processor records the moment when Timer 1 captures the firing pin contacting the conductive elastic metal sheet. The purpose is to align the firing pin trigger time with the time axis of the acceleration curve, achieving accurate correlation analysis of multiple parameters.

[0067] The circuit board can be set as a single piece or multiple pieces stacked together, and data and power are transmitted between the circuit boards through wires; the circuit board integrates a signal conditioning module (for amplification and filtering of the raw signal) and a processor.

[0068] The power module includes micro energy storage elements (such as button lithium batteries, thin lithium polymer batteries, etc.), a power management chip, and a voltage regulator unit. The power management chip manages the charging and discharging of the energy storage elements and provides overcharge and over-discharge protection. The voltage regulator unit divides the output voltage of the energy storage elements to the operating voltage required by each component of the system. Before the fuze overload test device is installed on the fuze, the power management chip is in a disabled state, the power supply is not connected to the circuit system, and it consumes almost no electrical energy, which greatly reduces the loss of the power module and extends the storage time of the power supply energy.

[0069] The mounting frame, made of high-strength materials (such as pins), is used to secure multiple circuit boards, maintaining their relative positions and preventing displacement or damage under high overload conditions. The mounting frame is not limited to pin soldering; any frame that can secure the circuit boards at the required spacing and maintain structural stability is acceptable. If insulators are used for fixing, electrical connections between the circuit boards are established using wires.

[0070] The data transmission interface (J30J) is used to establish temporary communication between the fuze overload test device and the host computer to achieve data transmission. It can be a wired connection (such as USB to TTL serial port) or wireless data transmission. This embodiment uses wired transmission. The system power-on operation can be completed by the host computer or by an external battery. That is, from the completion of the test system debugging to the launch of the projectile, it can be done without relying on the host computer.

[0071] The interior of the outer shell is filled with a protective filler material. Before curing, this material has good fluidity, which can fully fill the gaps inside the shell. After curing, it forms a high-strength structure, providing waterproof, moisture-proof, insulating, temperature-resistant, and shockproof protection for the internal components, significantly improving the system's resistance to emission overload and penetration overload. The protective filler material can be epoxy resin, silicone resin, polyurethane potting compound, acrylic potting compound, etc.

[0072] Further optimization is needed; the accelerometer can be a triaxial accelerometer or a single-axis accelerometer depending on requirements, ensuring that the detection axis coincides with the spring axis during installation; the protective filling material is made of epoxy resin-based polymer material, with a tensile strength of not less than 50MPa and an impact strength of not less than 15kJ / m² after curing, and can maintain stable performance within a temperature range of -40℃ to 85℃, meeting the fuze's usage requirements in complex environments; the processor is equipped with a multi-channel high-speed ADC function, with an overload sampling rate of not less than 10kHz, ensuring continuous acquisition of acceleration signals; for the instantaneous dynamic process of the firing pin, an interrupt mechanism is used to capture signals, with a trigger timing accuracy of not less than 2μs, ensuring accurate recording of the instantaneous parameters of the firing pin movement.

[0073] Further optimization is needed. For small- and medium-caliber fuses (such as ≤82mm mortar shell fuses), wired interfaces (micro USB interfaces, pin interfaces) are preferred for data transmission. These interfaces are compact and can be embedded in confined spaces. For medium- and large-caliber fuses (such as 155mm howitzer fuses), wireless transmission (such as Bluetooth, 4G, Zigbee, WIFI) can be integrated to support wireless data reading. This allows the system to be started and test data to be retrieved without disassembling the projectile.

[0074] like Figure 4As shown, 207 is the original detonator casing, which can be lengthened depending on the specific dimensions of the fuze overload testing device; 201 wire transmits the three conductive elastic metal sheet switching signals collected by the firing pin dynamic characteristic acquisition device to the processor 203; 205 provides power for the button-type rechargeable lithium battery; 206 is the accelerometer, which must be installed with one axis aligned with the projectile axis; 208 is the data transmission interface, which establishes temporary communication between the testing system and the host computer for powering on the system, configuring parameters, and reading data; wired or wireless transmission can be used; 209 is the protective filler material (epoxy resin potting) to resist launch overload and penetration overload. The epoxy resin is liquid before curing. It has excellent fluidity and, after curing, provides waterproofing, moisture resistance, insulation, temperature resistance, and shock absorption. It effectively prevents damage to components, wire breakage, and pad detachment caused by high impact overloads, greatly enhancing the impact resistance of circuit modules and components. 204 stainless steel serves as a fixing frame, which can be fixed by soldering with circuit pins to achieve physical connection, relative position fixation, and data transmission between circuit boards. Other methods can also be used to fix multi-layer circuit boards. If the fixing frame uses insulating material, the circuit boards can be connected by wires to achieve data transmission. There are no requirements for the arrangement order of the circuit boards containing each module, as long as space requirements are met, connections and fixation are secure, and the arrangement is convenient.

[0075] The hardware principle is as follows Figure 5 As shown, the storage test system consists of sensors, processors, power modules, signal conditioning modules, protective filling materials, and high-strength housings. After power-on, the system enters a waiting acquisition state, cyclically sampling in the negative delay region without recording. When the overload is greater than or equal to the first set threshold (|50|g), the signal conditioning module conditions the signal output by the accelerometer. The conditioned acceleration signal is then converted by an ADC and stored in the memory. When the overload is less than the second set threshold (|50|g), the system returns to the waiting acquisition state and enters a low-power state, waiting for data recovery and reading.

[0076] (3) Host computer The host computer in this invention is an external auxiliary device, which is a general-purpose computer (such as a desktop computer or a laptop computer). It establishes a temporary connection with the "fuze overload test device" through a data transmission interface. It does not participate in the core data acquisition, processing or storage logic inside the fuze. Its functions are limited to the following aspects: sending power-on command, configuring test parameters, initialization triggering, data reading, memory erasure and auxiliary analysis support.

[0077] Before testing, power is supplied to the fuze overload testing device via the data transmission interface, enabling and locking the power management chip to maintain power supply. The host computer transmits basic test parameters to the fuze overload testing device, including: the first set threshold for overload acquisition (the overload value that triggers acquisition), the second set threshold (the overload value that stops acquisition), the amount of buffered data in the negative delay storage area (e.g., 128 sets of historical data), and the sampling frequency. These parameters serve only as initial inputs to the fuze overload testing device and are executed by the system's built-in processor according to preset logic. The host computer does not participate in real-time parameter adjustment or logic control. The trigger system completes initialization (including timer initialization, sensor initialization, etc.). After initialization, the host computer disconnects from the system. After the test is completed, the host computer reads the test data (including firing pin activation time, full ballistic overload data, calculated firing pin velocity, impact energy, number of overload data acquisitions, etc.) from the storage unit of the fuze overload test device through the data transmission interface. The data format is a general text format (such as CSV format), which can be directly imported into general tools such as Excel and MATLAB for subsequent analysis (such as plotting overload-time curves, calculating the correlation between firing pin kinetic energy and overload, etc.), without the need for special analysis software.

[0078] This invention also provides a test method based on the above-mentioned comprehensive test system for dynamic characteristics and overload environment of fuse firing pin, including... Step S1: Configure test parameters Interface connection: Establish a communication connection between the test system and the host computer through the data transmission interface of the fuze overload test device.

[0079] Parameter settings: The host computer sets the test parameters for the fuze overload test device through the data transmission interface. The test parameters include the system start acquisition condition (i.e., the first set threshold), the system stop acquisition condition (i.e., the second set threshold), the amount of data buffered in the negative delay storage area, the firing pin signal sampling frequency, and the acceleration signal sampling frequency.

[0080] Step S2: Test system embedded assembly Fuze modification: Disassemble the original rotor (including detonator) of the mechanical trigger fuze, retain the core structure such as the rotor seat and detonation tube housing; modify the bottom of the rotor seat according to the required multi-layer circuit board and support pad size to ensure that the multi-layer circuit board of the firing pin dynamic characteristic acquisition device can be stably embedded.

[0081] Assembly of the firing pin dynamic characteristic acquisition device: embed the support pad into the rotor seat mounting slot, stack multiple circuit boards in sequence and calibrate the coaxiality of the through holes to ensure that the firing pin movement path is aligned with the through holes; weld conductive elastic metal sheets on both sides of the through holes of each layer of circuit boards, and connect each layer of circuit boards to the fuze overload test device through wires; install the original fuze safety system cover plate and fix it with fasteners.

[0082] Assembly of the fuze overload test device: The processor, accelerometer, and power module are soldered onto the circuit board, and the circuit boards are connected by a fixed frame and encapsulated in the outer shell (modified from the original detonation tube shell of the fuze); the outer shell is fixed to the rotor seat by a detachable connection method (such as threads), and protective filling material is injected into the shell. After curing, the assembly is completed; the original ignition logic and service operation procedures of the fuze are not changed throughout the process.

[0083] Step S3: Full ballistic data acquisition Loading and firing: After powering on the fuse equipped with the test system, install it onto the projectile, load it into the gun according to the standard procedure, and fire.

[0084] Start of data acquisition: After the test system is powered on, the accelerometer monitors the acceleration signal in real time, but does not store it; when the projectile is launched and the fuze overload reaches the first set threshold, the fuze overload test device automatically switches to the data acquisition and storage mode, and synchronously and cyclically executes the following steps: S31 captures the electrical signal of the firing pin turning on each layer of conductive elastic metal sheet and records the moment of conduction; The S32 collects the full trajectory acceleration data of the fuze; S33 uses a negative latency algorithm to write the previous historical data and real-time data that have reached the first set threshold into the storage unit.

[0085] S34 stops data acquisition. When the projectile acceleration drops below the second set threshold, the system stops data acquisition and returns to a low-power state where it is waiting to acquire data.

[0086] Step S4: Data Reading and Analysis Data processing: The processor of the fuze overload test device uses the ADC sampling start count as a reference to align the time axis of the firing pin conduction signal and the acceleration signal; based on the spacing of the multi-layer circuit boards and the time difference of conduction, it calculates the relative acceleration, absolute acceleration and motion speed of the firing pin; combined with the acceleration data at the corresponding time, it generates an overload curve and marks the firing pin trigger time and the firing pin speed at this time on the overload curve.

[0087] Data recovery: The fuze overload test device is recovered and connected to the host computer through the data transmission interface to read the firing pin conduction time data and full ballistic acceleration data in the storage unit.

[0088] Reliability assessment: The ignition reliability of the fuze is assessed based on whether the firing pin speed meets the fuze firing threshold and the impact of overload on the firing pin speed. If a "missed" situation occurs, the cause is located by correlating the data (such as insufficient overload causing the firing pin speed to be too low).

[0089] This invention can simultaneously acquire "full ballistic overload curve, firing pin initiation / trigger point, firing pin velocity / acceleration / energy". In the firing pin dynamic characteristic acquisition device, the time it takes for the firing pin to pierce the detonator is measured by connecting the firing pin to a conductive elastic metal sheet and establishing a circuit. Dynamic characteristics (firing time, pin penetration velocity, acceleration, and firing pin energy) are calculated based on the time difference between the multiple conductive elastic metal sheets connected to the circuit and the spacing between the sheets. In the fuze overload testing device, an acceleration sensor monitors the acceleration signal in real time. Overload acquisition is completed by setting a first threshold and a second threshold, and the complete acceleration curve is stored using negative delay technology. Finally, the correlation between the fuze overload curve and the trigger time is achieved by aligning the firing pin trigger time with the overload curve time axis. This invention can accurately quantify the correspondence between "overload - firing pin dynamic characteristics - firing result", clarify the influence weight of each parameter on misfire, and provide data support for fuze structure optimization.

[0090] In summary, the above are merely preferred embodiments of the present invention and are not intended to limit the scope of protection of the present invention. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

Claims

1. A comprehensive testing system for the overload and firing pin dynamic characteristics of a trigger fuse hitting a target, characterized in that, This includes a firing pin dynamic characteristic acquisition device and a fuze overload testing device; The firing pin dynamic characteristic acquisition device is installed in the rotor seat after the rotor has been removed. It includes a multi-layer circuit board, a conductive elastic metal sheet, and a support pad. The multi-layer circuit board is arranged at intervals along the firing pin movement direction, and each layer of the circuit board has a through hole for the firing pin to pass through. The conductive elastic metal sheet is installed at the through hole and is used to make contact and conduction when the firing pin passes through. The support pad is used to adjust the height of the multi-layer circuit board so that the contact point of the conductive elastic metal sheet of any middle layer of the circuit board is on the same plane as the original detonator end face. The fuze overload testing device is installed in the shell of the detonator tube after the pyrotechnic components have been removed. It includes an accelerometer and a processor. The accelerometer senses the full-trajectory overload of the projectile. The processor monitors the overload value sensed by the accelerometer in real time. If the detected overload value is greater than or equal to a first set threshold, it starts storing the detected overload value until the detected overload value is less than a second set threshold, at which point it stops storing and generates an overload curve. On the other hand, it monitors the conduction status of the multilayer circuit board, calculates the firing pin speed and firing pin impact energy, and marks the firing pin triggering time and firing pin speed on the overload curve.

2. The testing system as described in claim 1, characterized in that, The portion of the conductive elastic metal sheet that contacts the firing pin has a curved structure.

3. The testing system as described in claim 1, characterized in that, The rotor seat is machined and modified: the original mounting chamber of the rotor seat is enlarged and bored flat. The geometric center of the chamber, the axis of the rotor seat and the motion axis of the firing pin are coincident after the modification, and the inner diameter of the chamber is completely matched with the outer diameter of the multilayer circuit board. The through hole of the multilayer circuit board is located at the geometric center of the circuit board.

4. The testing system as described in claim 1, characterized in that, Based on the original rotor's eccentricity, through holes are set at the corresponding eccentric positions on the multilayer circuit board.

5. The testing system as described in claim 1, characterized in that, If the internal space of the detonation tube shell is insufficient, it is modified into an extended version using the same material. The inner diameter, outer diameter, and threaded connection interface of the extended shell are precisely matched with the original structure.

6. The testing system as described in claim 1, characterized in that, The fuze overload testing device also includes a fixed frame for fixing the circuit board that carries the processor and signal conditioning module.

7. The testing system as described in claim 1, 5, or 6, characterized in that, The interior of the outer shell is filled with protective padding material.

8. The testing system as described in claim 1, characterized in that, The processor uses two timers of different frequencies to monitor the overload value sensed by the accelerometer and the conduction status of the multilayer circuit board; among them, the high-frequency timer A continuously monitors the conduction status of the multilayer circuit board, and the low-frequency timer B monitors the overload value; timer A has a higher priority than timer B. When the processor detects an overload value greater than or equal to the first set threshold, the two timers align their data based on that moment.

9. The testing system as described in claim 1, characterized in that, The negative delay technology is adopted to record not only the real-time overload data collected after the fuze overload is greater than or equal to the first set threshold, but also the historical overload data collected during a period of time before the fuze overload is greater than or equal to the first set threshold, so as to ensure the data integrity of the overload curve.

10. A comprehensive testing method for fuses using the testing system described in any one of claims 1 to 9, characterized in that, include: S1, Modify the fuse to be tested, install the test system, and inject test parameters from the host computer; S2, after powering on the fuse equipped with the test system, install it onto the projectile, load it into the cannon, and fire it; S3, the processor makes a real-time judgment on the fuze overload sensed by the accelerometer. If the fuze overload reaches the first set threshold, it synchronously collects and records the level signal of the firing pin conducting each layer of conductive elastic metal sheet, as well as the overload value sensed by the accelerometer. S4, when the sensed fuse overload is less than the second set threshold, stop data acquisition and return to step 3 until the projectile hits the ground; S5, the processor aligns the firing pin conduction signal with the time axis of the fuze overload signal based on the time when the fuze overload reaches the first set threshold. Based on the spacing between the multi-layer circuit boards and the time difference between conduction, the relative acceleration, absolute acceleration, and velocity of the firing pin are calculated; combined with the acceleration data at the corresponding time, an overload curve is generated, and the firing pin trigger time and the firing pin velocity at that time are marked on the overload curve; S6. Evaluate the ignition reliability of the fuze based on whether the firing pin speed meets the fuze ignition threshold and the impact of fuze overload on the firing pin speed; if a "missed" situation exists, locate the cause through correlation data.

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