Hard target recognition composite inertial sensor and recognition method

Abstract

The invention provides a hard target identification composite inertial sensor and an identification method. According to the composite inertial sensor, a magnetoelectric speed sensing assembly and a tri-state inertial switch assembly are composited in the same shell, and a magnet of the magnetoelectric speed sensing assembly and an inertial rod of the tri-state inertial switch assembly are stacked up and down and make contact with each other in an initial state. And a magnetoelectric spring of the magnetoelectric speed sensing assembly is coaxially sleeved outside a switch spring of the three-state inertia switch assembly, so that a mutually nested coaxial structure is formed. The two sensors of the magnetoelectric speed sensing assembly and the three-state inertia switch assembly are integrated in a limited space through structural design, a first-layer target penetrating signal, the number of layers and a target outlet signal of a fuze can be accurately recognized, dynamic details in the penetration process can be obtained, the device can be used for various penetration scenes such as a single-layer target, a multi-layer target and a thick target, and the application range is wide. And the working condition adaptive capacity of the fuze is obviously enhanced.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of hard target recognition, and particularly relates to a hard target recognition composite inertial sensor and a recognition method. BACKGROUND

[0002] Penetration fuze is the "senses" and "brain" of hard target penetration weapon (commonly known as "earth-penetrating bomb"), which perceives and processes information through target detection and recognition technology, controls the explosion of ammunition at a suitable position in the target, and plays an important role in maximizing the damage effect of ammunition. In the penetration fuze, the inertial sensor as an important information detection element, the pros and cons of the overload signal it acquires affect the difficulty of signal processing and the accuracy of initiation control.

[0003] The magneto-electric velocity sensor and the three-state inertial switch are two new types of sensors.

[0004] The three-state inertial switch is a new type of inertial switch designed based on the principle of inertial switch, and its structure and equivalent circuit are shown in Figure 1 When the three-state switch is in a steady state, the output electrode is in contact with the upper contact column through the spring mass block, the output end is short-circuited to the ground, the circuit outputs a low level, and this state is called the "initial state" of the three-state switch. When the three-state switch is subjected to an external overload impact, if the inertial force generated by the impact is greater than the resistance of the spring pre-compression, the mass block will start to move. After generating sufficient displacement, the mass block is separated from the upper contact column at the initial position, so that the output state changes, and at this time the output end outputs the voltage on the voltage dividing resistor, which is called the intermediate state of the three-state switch. If the energy of the external impact is large enough, the mass block can move to the maximum stroke position and contact the lower contact column, and at this time the output end is directly connected to the positive electrode of the power supply, outputting the power supply voltage V CC , which is called the "final state" of the three-state switch.

[0005] Compared with the conventional switch, the three-state switch can start to move and complete the switching from the initial state to the intermediate state under small impact, which significantly improves the dynamic response of the target recognition. At the same time, since the three-state switch has a final state, on the one hand, when the impact energy is large enough, the mass block can only move to the maximum stroke position, which ensures the anti-interference ability of the three-state switch in thick target recognition; on the other hand, when the target is about to be out, as long as the inertial force of the overload is less than the spring resistance of the mass block at the final state position, the mass block will be separated from the base, and the final state will be converted to the intermediate state, which greatly improves the recognition sensitivity of the out-of-target time in the thick target penetration scene where the impact acceleration changes slowly, and the unloading feature is obvious.

[0006] The magneto-electric velocity sensor uses a magnet as a mass block, and identifies the penetration process by collecting the magneto-electric signal in the movement process of the magnet. Figure 2As shown, the magneto-electric velocity sensor is internally composed of an inertial system, a support structure and a conversion element. The conversion element includes a magnet and a coil. The magnet is also a mass block of the inertial system, the bottom surface of which is supported by a spring, and the top surface is a skeleton, which and the limiting structure determine the maximum stroke of the magnet. When the impact overload is generated by the penetrating projectile hitting the target, the magnet generates an induced electromotive force due to the relative motion with the coil, and the size of the induced electromotive force is positively correlated with the relative motion speed between the magnet and the coil.

[0007] Figure 3 The conventional switch signal (green) and the magneto-electric sensor signal (blue) when the ammunition penetrates the multi-layer target plate at high speed are shown, wherein the switch signal is very chaotic and it is difficult to identify the layer information; the magneto-electric sensor can better count the layers, and the layer counting signal (black) interval is well matched with the target plate arrangement in the test field, and it can be seen that the magneto-electric sensor has better robustness when the signal is stuck and mixed. In the target range test of the multi-layer working condition, the signal of the magneto-electric sensor is clearer than the layer information of the relative acceleration sensor signal, which proves its resistance to signal sticking.

[0008] In summary, the existing problems of the hard target recognition inertial sensor are: (1) The first layer into the target time recognition of the magneto-electric sensor is unstable Because the starting threshold of the magneto-electric sensor is usually high, in the working condition of penetrating multi-layer target plate, the front cabin of the projectile will play a certain buffering role when the projectile collides with the first layer of target plate, resulting in a weak first layer penetration signal, and thus the fuze cannot identify the first layer penetration signal, thereby causing the number of layers to be less.

[0009] (2) The three-state inertial switch is difficult to deal with complex penetration Due to the limitation of its own working principle, the three-state inertial switch can only output three discrete state signals, which makes it have obvious limitations when facing complex and variable penetration process. Because the available overload information is extremely limited, this type of switch is difficult to capture the dynamic details in the penetration process, such as the conversion of different media, the instantaneous change of the projectile attitude, the overload fluctuation caused by material non-uniformity and other key features. Therefore, in the application scenarios that require fine identification of penetration layers, judgment of medium type or decoupling of complex overload curve, the information dimension provided by the three-state switch is obviously insufficient, and it is difficult to support effective analysis and accurate judgment of the whole penetration process. SUMMARY

[0010] Therefore, the present application provides a hard target recognition composite inertial sensor, which integrates a magneto-electric velocity sensor component and a three-state inertial switch component in a limited space through structural design, which can not only accurately identify the first layer penetration signal, the number of layers and the out-of-target signal of the fuze, but also obtain the dynamic details in the penetration process.

[0011] To solve the above technical problems, the present application is implemented as follows.

[0012] A hard target identification composite inertial sensor, which combines a magneto-electric speed sensing component and a three-state inertial switch component in the same shell; The magneto-electric speed sensing component includes a framework, a magnet, a coil, a magneto-electric spring and a magneto-electric signal component; the three-state inertial switch component includes an inertial rod, a switch spring, a guide seat and a three-state signal component; The lower end surface of the framework is mounted on the guide seat; the coil is wound on the outer surface of the framework, and the magnet is mounted in the guide channel provided by the internal cavity of the framework; the magneto-electric spring is pre-compressed, with its upper end abutting against the lower surface of the magnet and its lower end abutting against the guide seat to limit the position; the magneto-electric signal component is connected to the coil; The upper end surface of the inertial rod abuts against the lower surface of the magnet in the initial state, and the lower part of the rod is located in the guide cylinder provided by the guide seat; the bottom of the guide channel of the guide cylinder is the farthest distance for the movement of the guide cylinder; the magneto-electric spring is pre-compressed and arranged inside the magneto-electric spring and outside the guide cylinder; one end of the magneto-electric spring is limited by the step on the inertial rod, and the other end is limited by the guide seat; the three-state signal component gives different signals when the three-state inertial switch component is in three states; The starting threshold of the magnet is greater than the starting threshold of the inertial rod.

[0013] Preferably, the three-state signal component includes an upper conductive sheet, a lower conductive sheet, a switch conductive sheet, an upper conductive sheet lead, a lower conductive sheet lead, a switch wire and a three-state voltage output circuit; The switch conductive sheet is arranged above the magnet; when the magnet and the inertial rod are both in the initial position, the switch conductive sheet is in contact with the magnet, and the inertial rod is in electrical communication with the switch conductive sheet through the magnet; The middle part of the guide seat protrudes as a guide cylinder, and the periphery of the guide cylinder is provided with a limiting groove; the upper conductive sheet is arranged in the limiting groove; the lower end of the switch spring is limited by the limiting groove and always contacts the upper conductive sheet; The lower conductive sheet is arranged at the bottom of the internal guide channel of the guide cylinder, which is the farthest distance for the movement of the inertial rod; The upper conductive sheet lead is connected to the upper conductive sheet, the lower conductive sheet lead is connected to the lower conductive sheet, and the switch wire is connected to the switch conductive sheet; the upper conductive sheet lead, the lower conductive sheet lead and the switch wire are connected to the three-state voltage output circuit.

[0014] Preferably, the limiting groove is an annular groove, and the upper conductive sheet is also annular and laid on the bottom of the annular groove.

[0015] Preferably, a recess for mounting the switch conductive sheet is formed in the upper end surface of the framework, for mounting the switch conductive sheet.

[0016] Preferably, the upper conductive sheet lead passes through the lead-out hole formed in the guide seat, the gap between the framework and the shell, and the opening on the shell in sequence, and is led out of the shell. The lower conductive sheet lead wire sequentially passes through the lead-out hole of the guide seat, the gap between the framework and the shell, and the opening of the shell.

[0017] Preferably, a buffer sheet is arranged at the bottom of the guide cylinder in the guide seat and below the lower conductive sheet.

[0018] Preferably, the three-state voltage output circuit comprises a voltage dividing circuit composed of a power supply VCC, two groups of voltage dividing circuits and a ground GND; the power supply VCC is connected with the lower conductive sheet lead wire, the ground GND is connected with the switch wire, and the voltage dividing point is connected with the upper conductive sheet lead wire and serves as a three-state voltage output end.

[0019] Preferably, in the initial state, the inertial rod contacts the magnet, communicates with the three-state signal assembly through the conductive performance of the magnet and the switch spring, and outputs the initial state signal; the magnet does not move, and the magneto-electric signal assembly does not generate a signal. When the acceleration overload is greater than the starting threshold of the inertial rod during penetration of the target, the inertial rod moves downward first, separates from the magnet, and only communicates with the three-state signal assembly through the switch spring, and outputs the intermediate state signal; when the acceleration overload is further greater than the starting threshold of the magnet, the magnet moves downward, and the magneto-electric signal assembly generates a signal. With the continuation of the penetration process, the magnet and the inertial rod continue to move downward, and when the inertial rod reaches the farthest position of the guide cylinder, it communicates with the three-state signal assembly through the conductive performance of the conductive part at the farthest position and the switch spring, and outputs the final state signal.

[0020] The application provides a penetration recognition method of a hard target recognition composite inertial sensor, and adopts the above hard target recognition composite inertial sensor. For penetrating a single-layer or multi-layer target, the time when the three-state inertial switch assembly is first changed from the initial state to the intermediate state is taken as the criterion for entering the first layer of the target. The output signal of the magneto-electric speed sensing assembly is taken as the layer counting basis, and after the number of counted layers reaches a predetermined value, the delay setting time is detonated.

[0021] Preferably, when penetrating a thick target, the time when the three-state inertial switch assembly is first changed from the initial state to the intermediate state is taken as the entering time, and the time when the three-state inertial switch assembly is first changed from the intermediate state to the initial state is taken as the exiting time, and after the exiting signal is obtained, the delay setting time is detonated.

[0022] Advantages: (1) Compared with the magneto-electric speed sensor or the three-state inertial switch, the composite sensor has the advantage that the coaxial double-spring vibrator structure integrates the functions of the two kinds of inertial sensors, and compared with the scheme of separately using the two kinds of sensors, the space in the fuze is saved, which is beneficial to the optimization of the space in the fuze and the miniaturization design of the fuze.

[0023] (2) The coaxial double-spring vibrator structure of the composite sensor inherits the inhibition of adhesion of the spring vibrator structure. The magnetoelectric part outputs continuous values, which can better reflect the penetration characteristics and is mainly suitable for multi-layer penetration conditions; the switch part responds quickly, the signal is simple, and the unloading feature is obvious, which can be used for the first target layer counting or judging the penetration time of thick targets in multi-layer penetration. The fuze using the composite inertial sensor can adapt to single-layer, multi-layer, and thick target penetration and other penetration conditions. In the future, further signal processing and target recognition methods can be developed according to the signal characteristics obtained by the magnetoelectric and switch parts. BRIEF DESCRIPTION OF DRAWINGS

[0024] Figure 1 The structure of the prior art three-state inertial switch.

[0025] Figure 2 The structure of the prior art magnetoelectric speed sensor.

[0026] Figure 3 The comparison between the conventional switch signal and the magnetoelectric sensor signal when the ammunition penetrates the multi-layer target at high speed is shown.

[0027] Figure 4 The structure diagram of the hard target recognition composite inertial sensor of the present application.

[0028] Figure 5 The circuit diagram of the three-state voltage output circuit.

[0029] Figure 6 The output characteristics of the three-state inertial switch.

[0030] Figure 7 The simulation displacement output curve of the magnet in the composite sensor and the output voltage signal curve on the coil under the same overload input. DETAILED DESCRIPTION

[0031] Considering that the magnetoelectric speed sensor can obtain dynamic details in the penetration process and accurately identify the out-of-target and multi-layer target after entering the first layer target, but is not sensitive to the first layer penetration signal; the three-state inertial switch can accurately determine the first target entering and out-of-target time, which can make up for the magnetoelectric sensor, but due to the simple signal, it is difficult to deal with complex conditions and cannot capture the dynamic details in the penetration process. The magnetoelectric sensor can provide more complete penetration overload information in other conditions.

[0032] Therefore, the application provides a hard target recognition composite inertial sensor, which combines a magneto-electric speed sensing assembly and a three-state inertial switch assembly in the same shell, so that the two work together, the three-state switch can make up for the deficiency of the magneto-electric sensor that is not sensitive to the first layer penetration signal and has difficulty in recognizing the out-of-target signal when penetrating a thick target, and the magneto-electric sensor can provide more complete penetration overload information in other working conditions. Compared with a single magneto-electric sensor or a three-state switch, the composite sensor can be used in single-layer target, multi-layer target and thick target and other penetration scenes, significantly enhancing the working condition adaptability of the fuze.

[0033] In structure, the magnet of the magneto-electric speed sensing assembly and the inertial rod of the three-state inertial switch assembly are stacked up and down and in contact with each other in the initial state, and the magneto-electric spring of the magneto-electric speed sensing assembly is coaxially sleeved outside the switch spring of the three-state inertial switch assembly, so as to form a coaxial structure nested with each other, thereby reducing the overall volume.

[0034] In functional design, the magnet and the inertial rod are respectively used as the mass blocks of the two sensors, the starting threshold of the magnet is greater than that of the inertial rod, and no interference occurs during movement, so that the two sensors can play their respective roles without conflict.

[0035] The application will be described in detail below with reference to the drawings and examples.

[0036] Figure 4 The structure diagram of the hard target recognition composite inertial sensor of the embodiment of the application is shown. As shown in the figure, it comprises a shell 15 and a magneto-electric speed sensing assembly and a three-state inertial switch assembly combined in the shell.

[0037] The magneto-electric speed sensing assembly comprises a framework 4, a magnet 1, a coil 2, a magneto-electric spring 3 and a magneto-electric signal assembly. The three-state inertial switch assembly comprises an inertial rod 5, a switch spring 6, a guide seat 7 and a three-state signal assembly.

[0038] In the magneto-electric speed sensing assembly, the lower end surface of the framework 4 is mounted on the guide seat 7; the coil 2 is wound around the outer surface of the framework 4, and the magnet 1 is installed in the guide channel provided in the internal cavity of the framework 4. The magneto-electric spring 3 is pre-compressed, with its upper end abutting against the lower surface of the magnet 1 and its lower end abutting against the guide seat 7 to limit the position; the magneto-electric signal assembly is connected to the coil 2.

[0039] In the three-state inertia switch assembly, in the initial state, the upper end surface of the inertia rod 5 abuts against the lower surface of the magnet 1, and the lower rod is located in the guide cylinder 71 provided by the guide seat 7; the bottom of the guide channel of the guide cylinder 71 is the farthest distance for the movement of the guide cylinder 71; the magneto spring 3 is pre-compressed and is arranged on the inner side of the magneto spring 3 and the outer side of the guide cylinder; one end of the magneto spring 3 is limited by the step on the inertia rod 5, and the other end is limited by the guide seat 7; the three-state signal assembly gives different signals when the three-state inertia switch assembly is in three states.

[0040] The three-state signal assembly comprises an upper conductive sheet 8, a lower conductive sheet 9, a switch conductive sheet 10, an upper conductive sheet lead 11, a lower conductive sheet lead 12, a switch lead 13 and a three-state voltage output circuit. Figure 4 A preferred position of these components is shown. The ingenious structural design fully integrates the two sensors, which can reduce the occupied space.

[0041] The switch conductive sheet 10 is arranged above the magnet 1. When the magnet and the inertia rod are both in the initial position, the switch conductive sheet 10 is in contact with the magnet, and the inertia rod 5 is in electrical communication with the switch conductive sheet 10 through the magnet. Preferably, a recess for mounting the switch conductive sheet 10 is formed in the upper end surface of the framework 4, for mounting the switch conductive sheet 10.

[0042] The middle part of the guide seat 7 protrudes as a guide cylinder 71, and a limiting groove 72 is arranged on the periphery of the guide cylinder; the upper conductive sheet 8 is arranged in the limiting groove 72; the lower end of the switch spring 6 is limited by the limiting groove 72 and always contacts the upper conductive sheet 8; the upper conductive sheet 8, the switch spring 6 and the inertia rod 5 are in contact, which is a normally closed pole. Preferably, the limiting groove 72 is an annular groove, and the upper conductive sheet 8 is also annular and is laid on the bottom of the annular groove, so as to ensure that the rotation of the switch spring 6 will not affect the electrical connection.

[0043] The lower conductive sheet 9 is arranged at the bottom of the guide channel inside the guide cylinder 71 and at the farthest distance where the inertia rod 5 can move. The lower conductive sheet 9 is not in contact with the inertia rod 5 in the initial state and the intermediate state, which is a normally open pole.

[0044] In a preferred embodiment, a buffer sheet 14 is arranged below the bottom of the guide channel of the guide cylinder 71 and the lower conductive sheet 9, for buffering the overload impact force and avoiding damage to the conductive sheet.

[0045] The upper conductive sheet lead 11 is connected to the upper conductive sheet 8, the lower conductive sheet lead 12 is connected to the lower conductive sheet 9, and the switch lead 13 is connected to the switch conductive sheet 10; the upper conductive sheet lead 11, the lower conductive sheet lead 12 and the switch lead 13 are connected to the three-state voltage output circuit.

[0046] The upper conductive sheet lead 11 is led out through the leading-out hole of the guide seat 7, the gap between the framework 4 and the shell 15, and the opening of the shell 15 in sequence; the lower conductive sheet lead 12 is led out through the leading-out hole of the guide seat 7, the gap between the framework 4 and the shell 15, and the opening of the shell 15 in sequence.

[0047] Figure 5 A circuit diagram of the tri-state voltage output circuit is shown. As shown in the figure, the tri-state voltage output circuit comprises a voltage dividing circuit composed of a power supply VCC, two groups of voltage dividing circuits and a ground GND; the power supply VCC is connected with the lower conductive sheet lead 12, the ground GND is connected with the switch lead 13, and the voltage dividing point is connected with the upper conductive sheet lead 11 and serves as a tri-state voltage output terminal.

[0048] The working process of the composite inertial sensor is as follows: In the initial state, the inertial rod 5 contacts the magnet 1, and communicates with the tri-state signal assembly through the conductive performance of the magnet 1 and the switch spring 6, and outputs the initial state signal. The magnet 1 does not move, and the magneto-electric signal assembly does not generate a signal.

[0049] When penetrating the target, when the acceleration overload is greater than the starting threshold of the inertial rod 5, the inertial rod 5 moves downward first, and only communicates with the tri-state signal assembly through the switch spring 6, and outputs the intermediate state signal; when the acceleration overload is further greater than the starting threshold of the magnet, the magnet 1 moves downward, the magneto-electric signal assembly generates a signal, and can reflect the penetration process.

[0050] With the continuation of the penetration process, the magnet 1 and the inertial rod 5 continue to move downward, and when the inertial rod 5 reaches the farthest position of the guide cylinder 71, it communicates with the tri-state signal assembly through the conductive part at the farthest position and the conductive performance of the switch spring 6, and outputs the final state signal.

[0051] The composite sensor of the application adopts a pair of coaxial double-spring vibrator structures, and the design is more complex than a single inertial switch or magneto-electric sensor. When designing the structural parameters of the sensor, not only the overload characteristics under the penetration working condition are considered, but also the interference of the motion coupling between the two spring vibrator systems on the respective output signals is considered.

[0052] Through reasonable design of the switch spring, the magneto-electric spring, the inertial rod and the magnet, the starting threshold of the magnet is greater than the starting threshold of the inertial rod, and at the same time, the recovery threshold of the magnet is also greater than the recovery threshold of the inertial rod. It is ensured that the motion of the magnet and the motion of the inertial rod will not interfere with each other in theory, that is, it can be ensured that the magneto-electric sensor and the switch work independently of each other. The starting threshold and the recovery threshold are respectively equal to the pressure of the spring at the initial position and the maximum displacement in value.

[0053] The design of the starting threshold of the magnet 1 being greater than the starting threshold of the inertia rod 5 can be determined empirically or experimentally. More preferably, the following parameter design process is adopted to accurately design the hard target recognition composite inertia sensor structure based on working condition overload and motion decoupling. The specific design process is as follows: (1) Structure parameter design for working condition (penetration overload peak) Two kinds of impact overloads are considered: interference impact overload and effective impact overload.

[0054] The interference impact overload ( ) is the maximum overload that does not cause the composite sensor to generate an output. Generally, the maximum overload value that the fuze can withstand in a non-penetration environment (in the barrel, during flight, etc.) is set as the interference impact overload value, and the starting threshold of the spring oscillator system is required to be greater than this overload. This design reduces the possibility of false action of the sensor under the impact of the shock overload in the non-penetration working condition, and enhances the reliability of the fuze. In the pre-compressed spring oscillator system, the gravity of the mass block is usually much smaller than the spring pre-compression force, so the spring pre-compression force can be regarded as the starting threshold force of the system. At this time, the system parameters are required to satisfy the following first condition:

[0055] In the formula, is the stiffness coefficient of the switch spring 6, is the pre-compression amount of the switch spring 6, is the mass of the inertia rod 5 as the mass block. According to the principle of the composite sensor, the starting threshold of the switch part needs to be smaller than that of the magneto part, so it is only required to make the structure parameters of the spring mass block system of the switch part satisfy the first condition of the above formula.

[0056] The effective impact overload ( a 2) is the minimum overload under the premise that the recovery threshold of the magnet is greater than the recovery threshold of the inertia rod, and the sensor can work reliably. When the maximum overload generated during penetration is greater than the effective impact overload, the sensor generally can work reliably. "Reliable work" means: 1. The magneto part can work normally and output signals; 2. The three-state part can reach the final state, i.e. the output signal of the switch part is a three-state signal that completely contains the initial state, intermediate state and final state, compared with the signal that only exists in the initial state and intermediate state. The three-state signal contains more information, which is beneficial to subsequent signal processing and initiation control. Generally, the minimum value of the overload peak that may occur during penetration is regarded as the effective impact overload, and the return threshold of the spring mass block system is required to be smaller than the effective impact overload, satisfying the following second condition:

[0057] In the formula, is the maximum displacement of the inertia rod 5.

[0058] If the above first condition and the second condition appear contradictory, the value of the interference impact overload and the effective impact overload needs to be selected according to the safety, real-time and sensitivity of the compound inertial sensor for the hard target identification. Reducing the interference impact overload will reduce the safety of the fuze, leading to more false signals; increasing the effective impact overload will reduce the real-time and sensitivity of the fuze.

[0059] (2) Motion decoupling parameter design In the process of the compound inertial sensor, the switch signal is the main criterion for the projectile in and out of the target, so we hope that the real-time performance of the switch part is better; at the same time, we also hope that the motion between the two mass blocks in the coaxial double-spring oscillator system does not interfere with each other, and the requirements are: In the loading process of starting penetration, the penetration overload shows an increasing trend, and the inertial rod needs to move before the magnet, which requires that the starting threshold of the switch part be less than that of the magnetoelectric part. In the unloading process of ending penetration, the two mass blocks start to return, and the penetration overload shows a decreasing trend. In order to make the motion of the two mass blocks not interfere with each other, the magnet should start to return first, that is, the recovery threshold of the magnetoelectric part is greater than that of the switch part. In summary, in order to make the motion of the two mass blocks decoupled during starting and returning, the following conditions need to be met:

[0060] Wherein:

[0061] In the formula, the subscripts 1 and 2 represent the parameters of the magnetoelectric part and the switch part, respectively.

[0062] Combined with the first condition, the second condition and the third condition, the pre-compression, the stiffness coefficient, the mass of the mass block and the maximum displacement are designed to adapt, so that the starting threshold of the magnet 1 is greater than that of the inertial rod 5, and no interference occurs during the motion.

[0063] From the above analysis, when the system parameters meet the motion decoupling condition, the motion of the two mass blocks during starting and returning does not interfere with each other; to prove that the motion of the two mass blocks still does not interfere with each other during the whole process of the trip and return under ideal conditions, the force analysis of the mass block needs to be carried out first. First of all, define the whole process of trip / return as the process that the mass block starts to move until the mass block reaches the maximum displacement. This process does not include the rebound motion stage after the mass block collides with the limit, which is difficult to predict and control. Under ideal conditions, during the process of projectile penetration, the mass block in the sensor is mainly affected by the inertial force and the spring pressure, so that t the mass block​i The acceleration is:

[0064] In the formula, g ( t )yes t The overload acceleration that constantly acts on the mass block x i (t) represents t The displacement of the mass block at any given time.

[0065] Taking the overload direction as positive, compare the acceleration values ​​of the magnet and the inertial rod at the same displacement s: Since the magnet and the inertial rod are located within the same sensor, the overload acceleration experienced by these two masses is... g ( t They can be considered equal. Assume the magnet and the inertial rod are at the same displacement x. Both are subjected to the same overload acceleration g(t). The magnitudes of the accelerations of the magnet and the inertial rod are compared by subtracting their respective accelerations:

[0066] Let the function be:

[0067] According to the motion decoupling condition, we can obtain:

[0068] because y 1( x ), y 2( x ) is a linear function. Based on the above conditions, it's easy to see that when 0 < x < x M At that time, y1( x ) <y2( x Therefore:

[0069] The above equation proves that when the decoupling condition is met, at the same displacement, the acceleration of the inertial rod is always greater than the acceleration of the magnet. This indicates that during the outward journey, when the magnet and the inertial rod approach each other, there must be a tendency for them to move away from each other; similarly, the same conclusion can be drawn during the return journey. This characteristic helps reduce motion interference between the two mass blocks, but their motion may still interfere with each other. To ensure that the two mass blocks will not collide at all during the outward and return journeys under certain parameter conditions, it is necessary to verify this by solving the analytical solution of the motion differential equation.

[0070] Based on the above structure and parameter design, the recognition scheme of the hard target recognition composite inertial sensor based on the present invention is as follows.

[0071] Figure 6 The output characteristics of the three-state inertial switch are shown. Figure 6 (a) in FIG. 1 is a simulation curve of the displacement of the inertial rod of the composite sensor switch under the action of a half-sine overload (the rebound in the figure indicates that the inertial rod collides with the magnet or the sensor structure), Figure 6 (b) in FIG. 1 is a simulation curve of the half-sine overload signal and the switch output. Under the action of the overload, the inertial rod first moves away from the initial position, and the output signal becomes the intermediate state; when the overload is large enough, the inertial rod reaches the limit position, and the output signal becomes the final state. After a period of time, when the overload value decays to below the return threshold, the inertial rod starts to return; and after stabilization, it remains in the initial state.

[0072] Figure 7 The simulation displacement output curve of the magnet in the composite sensor and the output voltage signal curve on the coil under the same overload input are shown. A voltage threshold is set in advance, and when the negative voltage on the coil reaches this threshold during the penetration process, the number of penetrated layers is increased by 1, and the signal in the next period of time is shielded to prevent multiple negative vibration peaks from occurring during the penetration of the same layer, resulting in multiple layer identification. Because the magnet needs to spend a period of time to reach a certain speed after starting to move to trigger the voltage threshold, the response time of the magnetoelectric part to the penetration is slower than that of the switch part; and when the magnet is at the limit position, the output voltage on the coil is 0, which is particularly evident during the penetration of a thick target, which makes it difficult for the magnetoelectric part to fully reflect the penetration process in such cases.

[0073] According to the analysis of the output of the composite sensor under different working conditions, there are disadvantageous working condition intervals for both the magnetoelectric and switch parts in terms of layer identification or cavity identification. To make the composite sensor adapt to different working conditions (including penetrating a single layer of target, continuously penetrating multiple layers of target, penetrating a thick target, etc.), it is necessary to combine the characteristics of the magnetoelectric sensor and the three-state inertial switch, and develop a target identification strategy based on the signals of the magnetoelectric and switch parts.

[0074] (1) For the case of penetrating a single layer or multiple layers of target: Because the signal of the magnetoelectric sensor can reflect more target characteristics, the output signal of the magnetoelectric part is mainly used as the criterion for layer counting. According to the working principle of the magnetoelectric sensor, a negative voltage threshold is set according to the approximate strength and thickness of the target, and the absolute value of the negative voltage of the magnetoelectric part is greater than or equal to the absolute value of the threshold, and the number of layers is increased by 1; thereafter, a pre-set shielding time is entered, and during this period, even if the magnetoelectric part signal reaches the threshold again, the signal processing part will not perform layer counting operation, avoiding the influence of multiple negative peaks of the magnetoelectric part signal caused by the high-frequency vibration of the overload acceleration signal on the layer identification when penetrating the same layer of target. After the number of layers reaches the predetermined value, the detonation signal is sent after a certain time delay.

[0075] The front cabin of the penetration ammunition head equipped with components first collides with the target plate, and the front cabin absorbs part of the overload energy when it is destroyed, which buffers the projectile body, resulting in a lower overload acceleration value acting on the tail sensor. Since the start threshold of the three-state inertial switch is small when the decoupling condition is met, the start signal of the switch part can be used as the criterion for the first layer of penetration.

[0076] Therefore, for the case of penetrating a single-layer or multi-layer target, the penetration recognition method of the present application is: First, the time when the three-state inertial switch component reaches the intermediate state from the initial state for the first time is used as the criterion for the first layer of penetration. Subsequently, the output signal of the magneto-electric speed sensing component is used as the layer counting basis, and after the number of layers reaches the predetermined value, the delay set time is detonated.

[0077] (2) The case of penetrating thick targets When penetrating thick targets, the time of entering and exiting the target is the key to target recognition. The output of the switch part is used to determine the entry and exit time of the target. However, the signal of the magneto-electric part cannot fully reflect the entire penetration process, so it can only be used as a redundant criterion. Therefore, when penetrating thick targets, the time when the three-state inertial switch reaches the intermediate state from the initial state for the first time is used as the entry time, and the time when it returns to the initial state from the intermediate state for the first time is used as the exit time. After obtaining the exit signal, delay for a certain time to detonate. For the problem of time delay of switch signal returning to initial state, the delay amount of detonation time can be appropriately reduced according to the simulation results.

[0078] In summary, the above is only a preferred embodiment of the present application and is not intended to limit the scope of protection of the present application. Any modification, equivalent replacement, improvement, etc. made within the spirit and principles of the present application shall be included within the scope of protection of the present application.

Claims

1. A hard target recognition composite inertial sensor, characterized in that, A magnetoelectric velocity sensing component and a three-state inertial switch component are combined in the same housing; The magnetoelectric speed sensing component includes a frame (4), a magnet (1), a coil (2), a magnetoelectric spring (3), and a magnetoelectric signal component; the three-state inertial switch component includes an inertial rod (5), a switch spring (6), a guide seat (7), and a three-state signal component; The lower end face of the skeleton (4) is mounted on the guide seat (7); the outer surface of the skeleton (4) is wound with a coil (2), and the magnet (1) is installed in the guide channel provided by the cavity inside the skeleton (4); the magnetoelectric spring (3) is pre-compressed, with its upper end abutting against the lower surface of the magnet (1) and its lower end abutting against the guide seat (7) to limit the movement; the magnetoelectric signal assembly is connected to the coil (2). The upper end face of the inertial rod (5) abuts against the lower surface of the magnet (1) in the initial state, and the lower rod is located inside the guide tube (71) provided by the guide seat (7); the bottom of the guide tube (71) guide channel is the farthest distance the guide tube (71) moves; the magnetoelectric spring (3) is pre-compressed and is set inside the magnetoelectric spring (3) and outside the guide tube; one end of the magnetoelectric spring (3) is limited by the step on the inertial rod (5), and the other end is limited by the guide seat (7); the three-state signal component gives different signals when the three-state inertial switch component is in three states respectively; The starting threshold of the magnet (1) is greater than the starting threshold of the inertial rod.

2. The hard target recognition composite inertial sensor as described in claim 1, characterized in that, The three-state signal component includes an upper conductive plate (8), a lower conductive plate (9), a switch conductive plate (10), an upper conductive plate lead (11), a lower conductive plate lead (12), a switch line (13), and a three-state voltage output circuit; The switch conductive sheet (10) is positioned above the magnet (1); when both the magnet and the inertial rod are in their initial positions, the switch conductive sheet (10) is in contact with the magnet, and the inertial rod (5) is electrically connected to the switch conductive sheet (10) through the magnet. The guide seat (7) has a protruding guide cylinder (71) in the middle, and a limiting groove (72) is provided around the guide cylinder; the upper conductive sheet (8) is set in the limiting groove (72); the lower end of the switch spring (6) is limited by the limiting groove (72) and always contacts the upper conductive sheet (8); The lower conductive sheet (9) is located at the bottom of the guide channel inside the guide cylinder (71) and at the farthest point where the inertial rod (5) can move; The upper conductive lead (11) is connected to the upper conductive sheet (8), the lower conductive lead (12) is connected to the lower conductive sheet (9), and the switch line (13) is connected to the switch conductive sheet (10); the upper conductive lead (11), the lower conductive lead (12) and the switch line (13) are connected to the three-state voltage output circuit.

3. The hard target recognition composite inertial sensor as described in claim 2, characterized in that, The limiting groove (72) is an annular groove, and the upper conductive sheet (8) is also annular and is laid at the bottom of the annular groove.

4. The hard target recognition composite inertial sensor as described in claim 2, characterized in that, The upper surface of the frame (4) is provided with a groove for installing the switch conductive sheet (10) for installing the switch conductive sheet (10).

5. The hard target recognition composite inertial sensor as described in claim 2, characterized in that, The upper conductive sheet lead wire (11) is led out sequentially through the lead-out hole opened in the guide seat (7), the gap between the skeleton (4) and the outer shell (15), and the opening on the outer shell (15); The lower conductive sheet lead wire (12) is led out sequentially through the lead-out hole opened in the guide seat (7), the gap between the skeleton (4) and the outer shell (15), and the opening on the outer shell (15).

6. The hard target recognition composite inertial sensor as described in claim 2, characterized in that, A buffer sheet (14) is provided at the bottom of the guide cylinder (71) and below the lower conductive sheet (9) in the guide seat (7).

7. The hard target recognition composite inertial sensor as described in claim 2, characterized in that, The three-state voltage output circuit includes a voltage divider circuit consisting of a power supply VCC, two voltage divider circuits and ground GND; the power supply VCC is connected to the lower conductive plate lead (12), the ground GND is connected to the switch line (13), and the voltage divider point is connected to the upper conductive plate lead (11) and serves as the three-state voltage output terminal.

8. The hard target recognition composite inertial sensor as described in any one of claims 1-7, characterized in that, In the initial state, the inertial rod (5) contacts the magnet (1), and is connected to the three-state signal component through the conductivity of the magnet (1) and the switch spring (6), and outputs the initial state signal; When the magnet (1) does not move, the magnetoelectric signal component does not generate a signal; When penetrating the target, when the acceleration overload is greater than the activation threshold of the inertial rod (5), the inertial rod (5) moves downward first, disengages from the magnet (1), and is connected to the three-state signal component only through the switch spring (6), outputting an intermediate state signal; when the acceleration overload is further greater than the activation threshold of the magnet, the magnet (1) moves downward, and the magnetoelectric signal component generates a signal; As the penetration process continues, the magnet (1) and the inertial rod (5) continue to move downward. When the inertial rod (5) reaches the farthest position of the guide tube (71), it connects with the three-state signal component through the conductivity of the conductive part at the farthest position and the switch spring (6) to output the final state signal.

9. A penetration identification method using a hard target recognition composite inertial sensor, characterized in that, The method employs the hard target identification composite inertial sensor as described in any one of claims 1-8; the method includes: When used to penetrate single-layer or multi-layer targets, the moment when the three-state inertial switch assembly first reaches the intermediate state from the initial state is used as the criterion for penetrating the first layer of the target. Subsequently, the output signal of the magnetoelectric velocity sensor component is used as the basis for layer counting. After the number of layers reaches the predetermined value, the detonation is delayed by a set time.

10. The method as described in claim 9, characterized in that, When penetrating a thick target, the moment when the three-state inertial switch assembly first reaches the intermediate state from the initial state is taken as the target entry moment, and the moment when it first returns from the intermediate state to the initial state is taken as the target exit moment. After obtaining the target exit signal, the detonation is initiated after a set time delay.

Images