In this paper,a dynamic modeling method of motor driven electromechanical system is presented,and the uncertainty quantification of mechanism motion is investigated based on this method.The main contribution is to pro...In this paper,a dynamic modeling method of motor driven electromechanical system is presented,and the uncertainty quantification of mechanism motion is investigated based on this method.The main contribution is to propose a novel mechanism-motor coupling dynamic modeling method,in which the relationship between mechanism motion and motor rotation is established according to the geometric coordination of the system.The advantages of this include establishing intuitive coupling between the mechanism and motor,facilitating the discussion for the influence of both mechanical and electrical parameters on the mechanism,and enabling dynamic simulation with controller to take the randomness of the electric load into account.Dynamic simulation considering feedback control of ammunition delivery system is carried out,and the feasibility of the model is verified experimentally.Based on probability density evolution theory,we comprehensively discuss the effects of system parameters on mechanism motion from the perspective of uncertainty quantization.Our work can not only provide guidance for engineering design of ammunition delivery mechanism,but also provide theoretical support for modeling and uncertainty quantification research of mechatronics system.展开更多
In the internet of battlefield things, ammunition is becoming networked and intelligent, which depends on location information. Therefore, this paper focuses on the self-organized network collaborative localization of...In the internet of battlefield things, ammunition is becoming networked and intelligent, which depends on location information. Therefore, this paper focuses on the self-organized network collaborative localization of munitions with an aerial three-dimensional(3D) highly-dynamic topographic structure under a satellite denied environment. As for aerial networked munitions, the measurement of munitions is objectively incomplete due to the degenerated and interrupted link of munitions. For this reason, a cluster-oriented collaborative localization method is put forward in this paper. Multidimensional scaling(MDS) was first integrated with a trilateration localization method(TLM) to construct a relative localization algorithm for determining the relative location of a mobile cluster network. The information related to relative velocity was then combined into a collaborative localization framework to devise a TLM-vMDS algorithm. Finally, an iterative refinement algorithm based on scaling by majorizing a complicated function(SMACOF) was employed to effectively eliminate the influence of incomplete link observation on localization accuracy. Compared with the currently available advanced algorithms, the proposed TLM-vMDS algorithm achieves higher localization accuracy and faster convergence for a cluster of extensively networked munitions, and also offers better numerical stability and robustness for highspeed motion models.展开更多
In order to achieve the optimized design of a cased telescoped ammunition(CTA) interior ballistic design,a genetic algorithm was introduced into the optimal design of CTA interior ballistics with coupling the CTA inte...In order to achieve the optimized design of a cased telescoped ammunition(CTA) interior ballistic design,a genetic algorithm was introduced into the optimal design of CTA interior ballistics with coupling the CTA interior ballistic model. Aiming at the interior ballistic characteristics of a CTA gun, the goal of CTA interior ballistic design is to obtain a projectile velocity as large as possible. The optimal design of CTA interior ballistic is carried out using a genetic algorithm by setting peak pressure, changing the chamber volume and gun powder charge density. A numerical simulation of interior ballistics based on a 35 mm CTA firing experimental scheme was conducted and then the genetic algorithm was used for numerical optimization. The projectile muzzle velocity of the optimized scheme is increased from 1168 m/s for the initial experimental scheme to 1182 m/s. Then four optimization schemes were obtained with several independent optimization processes. The schemes were compared with each other and the difference between these schemes is small. The peak pressure and muzzle velocity of these schemes are almost the same. The result shows that the genetic algorithm is effective in the optimal design of the CTA interior ballistics. This work will be lay the foundation for further CTA interior ballistic design.展开更多
According to the compound packing problem in ammunition supply system in our army, the non-standard pallet series design model is proposed, and the original problem that can be solved as a set cover problem with a nes...According to the compound packing problem in ammunition supply system in our army, the non-standard pallet series design model is proposed, and the original problem that can be solved as a set cover problem with a nested bin-packing problem, is analyzed, then two heuristic algorithms are applied to solve the problem.展开更多
Security is a significant issue for everyone due to new and creative ways to commit cybercrime.The Closed-Circuit Television(CCTV)systems are being installed in offices,houses,shopping malls,and on streets to protect ...Security is a significant issue for everyone due to new and creative ways to commit cybercrime.The Closed-Circuit Television(CCTV)systems are being installed in offices,houses,shopping malls,and on streets to protect lives.Operators monitor CCTV;however,it is difficult for a single person to monitor the actions of multiple people at one time.Consequently,there is a dire need for an automated monitoring system that detects a person with ammunition or any other harmful material Based on our research and findings of this study,we have designed a new Intelligent Ammunition Detection and Classification(IADC)system using Convolutional Neural Network(CNN).The proposed system is designed to identify persons carrying weapons and ammunition using CCTV cameras.When weapons are identified,the cameras sound an alarm.In the proposed IADC system,CNN was used to detect firearms and ammunition.The CNN model which is a Deep Learning technique consists of neural networks,most commonly applied to analyzing visual imagery has gained popularity for unstructured(images,videos)data classification.Additionally,this system generates an early warning through detection of ammunition before conditions become critical.Hence the faster and earlier the prediction,the lower the response time,loses and potential victims.The proposed IADC system provides better results than earlier published models like VGGNet,OverFeat-1,OverFeat-2,and OverFeat-3.展开更多
This paper focuses on the dynamic tracking control of ammunition manipulator system. A standard state space model for the ammunition manipulator electro-hydraulic system(AMEHS) with inherent nonlinearities and uncerta...This paper focuses on the dynamic tracking control of ammunition manipulator system. A standard state space model for the ammunition manipulator electro-hydraulic system(AMEHS) with inherent nonlinearities and uncertainties considered was established. To simultaneously suppress the violation of tracking error constraints and the complexity of differential explosion, a barrier Lyapunov functionsbased dynamic surface control(BLF-DSC) method was proposed for the position tracking control of the ammunition manipulator. Theoretical analysis prove the stability of the closed-loop overall system and the tracking error converges to a prescribed neighborhood asymptotically. The effectiveness and dynamic tracking performance of the proposed control strategy is validated via simulation and experimental results.展开更多
The paper describes field test results of 7.62×51 mm M61 AP(armour piercing) ammunition fired into mild steel targets at an outdoor range.The targets varied from 10 mm to 32 mm in thickness.The tests recorded pen...The paper describes field test results of 7.62×51 mm M61 AP(armour piercing) ammunition fired into mild steel targets at an outdoor range.The targets varied from 10 mm to 32 mm in thickness.The tests recorded penetration depth,probability of perforation(i.e.,complete penetration),muzzle and impact velocities,bullet mass,and plate yield strength and hardness.The measured penetration depth exhibited a variability of approximately±12%.The paper then compared ballistic test results with predictive models of steel penetration depth and thickness to prevent perforation.Statistical parameters were derived for muzzle and impact velocity,bullet mass,plate thickness,plate hardness,and model error.A Monte-Carlo probabilistic analysis was then developed to estimate the probability of plate perforation of 7.62 mm M61 AP ammunition for a range of impact velocities,and for mild steels,and High Hardness Armour(HHA) plates.This perforation fragility analysis considered the random variability of impact velocity,bullet mass,plate thickness,plate hardness,and model error.Such a probabilistic analysis allows for reliability-based design,where,for example,the plate thickness with 95% reliability(i.e.only 1 in 20 shots will penetrate the wall) can be estimated knowing the probabilistic distribution of perforation.Hence,it was found that the plate thickness to ensure a low 5% probability of perforation needs to be 11-15% thicker than required to have a 50/50 chance of perforation for mild steel plates.Plates would need to be 20-30% thicker if probability of perforation is reduced to zero.展开更多
As part of a research program, it was desired to better understand the impact of the rotating chamber alignment with the barrel throat on the precision and accuracy of a novel cased telescoped(CT) ammunition firing ri...As part of a research program, it was desired to better understand the impact of the rotating chamber alignment with the barrel throat on the precision and accuracy of a novel cased telescoped(CT) ammunition firing rifle. In order to perform the study, a baseline CT ammunition chamber which was concentric with a Mann barrel bore was manufactured. Additionally, six chambers were manufactured with an offset relative to the barrel bore. These chambers were used to simulate a misaligned chamber relative to the bore axis. Precision and accuracy tests were then performed at 200 m in an indoor range under controlled conditions. For this project, 5.56 mm CT ammunition was used. As the chamber axis offset relative to the gun bore was increased, the mean point of impact was displaced away from the target center. The shift in the impact location is explained by the presence of in-bore yaw which results in lateral throw-off and aerodynamic jump components. The linear theory of ballistics is used to establish a relationship between the chamber misalignment and the resulting projectile mean point of impact for a rifle developed to fire CT ammunition. This relationship allows for the prediction of the mean point of impact given a chamber misalignment.展开更多
Aiming at the problem that the consumption data of new ammunition is less and the demand is difficult to predict,combined with the law of ammunition consumption under different damage grades,a Bayesian inference metho...Aiming at the problem that the consumption data of new ammunition is less and the demand is difficult to predict,combined with the law of ammunition consumption under different damage grades,a Bayesian inference method for ammunition demand based on Gompertz distribution is proposed.The Bayesian inference model based on Gompertz distribution is constructed,and the system contribution degree is introduced to determine the weight of the multi-source information.In the case where the prior distribution is known and the distribution of the field data is unknown,the consistency test is performed on the prior information,and the consistency test problem is transformed into the goodness of the fit test problem.Then the Bayesian inference is solved by the Markov chain-Monte Carlo(MCMC)method,and the ammunition demand under different damage grades is gained.The example verifies the accuracy of this method and solves the problem of ammunition demand prediction in the case of insufficient samples.展开更多
Euler angles and Euler kinematics equation of terminal sensing ammunition are expressed and rewritten by using quaternion to solve the singular problem in using Euler angles to describe the motion.The contrastive simu...Euler angles and Euler kinematics equation of terminal sensing ammunition are expressed and rewritten by using quaternion to solve the singular problem in using Euler angles to describe the motion.The contrastive simulations are performed in order to validate the correctness and advantage of the quaternion description.The simulation results show that the dynamic model with quaternion have stable solution,there is not singular point in the calculation,and the ballistic model rewritten by using the quaternion is suitable for describing the terminal sensing ammunition's scanning motion than the common Euler equation.展开更多
Some long distance air ammunition can be used to attack large still target. According to this character and according to the mathematical description of target-missile relative motion built by the message supplied by ...Some long distance air ammunition can be used to attack large still target. According to this character and according to the mathematical description of target-missile relative motion built by the message supplied by the strapdown inertial navigation system/global position system (SINS/GPS) of air ammunition, optimal guidance law is designed by applying optimal control theory. The simulation is provided to indicate that when the air ammunition reaches the target, its line-of-sight (LOS) and LOS angular rate can nearly equal zero. So the air ammunition can get good terminal attitude, and the air ammunition reaches the target at the expected velocity and heading.展开更多
In recent years, microstrip antennas have been more widely applied in satellite communications, mobile phones, unmanned aerial vehicle (UAV), and weapons. A micro-electro-mechanical systems-based (MEMS-based) high...In recent years, microstrip antennas have been more widely applied in satellite communications, mobile phones, unmanned aerial vehicle (UAV), and weapons. A micro-electro-mechanical systems-based (MEMS-based) high-resistance silicon C-band microstrip antenna array has been designed for the intelligent ammunition. The center frequency is 4.5 GHz. A cavity has been designed in substrate to reduce the dielectric constant of silicon and high-resistance silicon has been used as the material of substrate to improve the gain of antenna. It is very easy to be manufactured by using MEMS technology because of the improved structure of the antenna. The results show that the gain of the antenna is 8 dB and voltage standing wave ratio (VSWR) is less than 2 by the analysis and simulation in high freauencv structure simulator (HFSS).展开更多
Safety of underground ammunition storage is an important issue,especially during the accidental ignition of missiles.This work investigates the pressure and temperature distribution of the multi-layer underground ammu...Safety of underground ammunition storage is an important issue,especially during the accidental ignition of missiles.This work investigates the pressure and temperature distribution of the multi-layer underground ammunition storage with a pressure relief duct during the accidental ignition process of the missile.A large-scale experiment was carried out using a multi-layered restricted space with a pressure relief duct to simulate the underground ammunition store and a solid rocket motor to simulate the accidental ignition of the missile.The results show that when the motor gas mass flow increased by5.6 times,the maximum pressure of the ammunition storage increased by 5.87 times.At a certain motor flow rate,when the pressure relief exhaust area at the end of the relief duct was reduced by 1/2,the maximum pressure on the first layer did not change.But the rate of pressure relief was reduced and the time delayed for the pressure of ammunition store to drop to zero.In this experiment,when the motor ignition position was located in to the third layer ammunition chamber,the maximum pressure was reduced by 32.9%and also reduced the rate of change of pressure.In addition,for the experimental conditions,the theoretical analysis of the pressure relief of the ammunition storage is given by a simplified model.Based on the findings,some suggestions to the safety protection design of ammunition store are proposed.展开更多
The hard target smart fuse of penetration ammunition is developing to be smaller, lighter, smarter and multifunction. After analyzing the characteristics of high-g accelerating signals and the penetration algorithms, ...The hard target smart fuse of penetration ammunition is developing to be smaller, lighter, smarter and multifunction. After analyzing the characteristics of high-g accelerating signals and the penetration algorithms, this paper provides a solution of penetration ammunition fuse system based on embedded technology. This fuse system realizes acquisition of the high-g accelerating signals and uses the appropriate penetration algorithms to process them. The fuse system can not only make the same type of penetration ammunition to attack different kinds of objects accurately, but also meet the other requirements of the function of penetration ammunition fuse system.展开更多
Modern ammunition-rocket system is a complicated multidisciplinary system. During its development, undetermined factors will bring many risks. This paper elaborates the importance of risk analysis approach to ammuniti...Modern ammunition-rocket system is a complicated multidisciplinary system. During its development, undetermined factors will bring many risks. This paper elaborates the importance of risk analysis approach to ammunition-rocket system development and analyses various methods of risk analysis and estimation. Combined with practical situation of weapon system development, the risk measurement function with characteristics of risk preference is given provided that the risk preference characteristic of behavior maker is risk neutral of fixed constant. The development risk analysis based on risk measurement function enables effective risk decision to be made on the basis of quantified risk. Taking anti-helicopter intelligent mine warhead as an example, the paper verifies the efficiency of the method and shows that it has a scientific and practical value.展开更多
For the gradual maturity of Bayesian survival analysis theory,as well as the defects of the traditional methods for storage reliability evaluation,the Bayesian survival analysis method is proposed to build regression ...For the gradual maturity of Bayesian survival analysis theory,as well as the defects of the traditional methods for storage reliability evaluation,the Bayesian survival analysis method is proposed to build regression models for reliability in the random truncated test.These models can reflect the influences of different environments on the ammunition storage lifetime.As an example,the common exponential distribution is used here,and Markov chain Monte Carlo(MCMC)method based on Gibbs sampling dynamically simulates the Markov chain of the parameters' posterior distribution.Also,the parameters' Bayesian estimations are calculated in the random truncated condition.The simulation results show that the proposed method is effective and directly perceived.展开更多
基金supported by the National Natural Science Foundation of China(Grant Nos.11472137 and U2141246)。
文摘In this paper,a dynamic modeling method of motor driven electromechanical system is presented,and the uncertainty quantification of mechanism motion is investigated based on this method.The main contribution is to propose a novel mechanism-motor coupling dynamic modeling method,in which the relationship between mechanism motion and motor rotation is established according to the geometric coordination of the system.The advantages of this include establishing intuitive coupling between the mechanism and motor,facilitating the discussion for the influence of both mechanical and electrical parameters on the mechanism,and enabling dynamic simulation with controller to take the randomness of the electric load into account.Dynamic simulation considering feedback control of ammunition delivery system is carried out,and the feasibility of the model is verified experimentally.Based on probability density evolution theory,we comprehensively discuss the effects of system parameters on mechanism motion from the perspective of uncertainty quantization.Our work can not only provide guidance for engineering design of ammunition delivery mechanism,but also provide theoretical support for modeling and uncertainty quantification research of mechatronics system.
文摘In the internet of battlefield things, ammunition is becoming networked and intelligent, which depends on location information. Therefore, this paper focuses on the self-organized network collaborative localization of munitions with an aerial three-dimensional(3D) highly-dynamic topographic structure under a satellite denied environment. As for aerial networked munitions, the measurement of munitions is objectively incomplete due to the degenerated and interrupted link of munitions. For this reason, a cluster-oriented collaborative localization method is put forward in this paper. Multidimensional scaling(MDS) was first integrated with a trilateration localization method(TLM) to construct a relative localization algorithm for determining the relative location of a mobile cluster network. The information related to relative velocity was then combined into a collaborative localization framework to devise a TLM-vMDS algorithm. Finally, an iterative refinement algorithm based on scaling by majorizing a complicated function(SMACOF) was employed to effectively eliminate the influence of incomplete link observation on localization accuracy. Compared with the currently available advanced algorithms, the proposed TLM-vMDS algorithm achieves higher localization accuracy and faster convergence for a cluster of extensively networked munitions, and also offers better numerical stability and robustness for highspeed motion models.
文摘In order to achieve the optimized design of a cased telescoped ammunition(CTA) interior ballistic design,a genetic algorithm was introduced into the optimal design of CTA interior ballistics with coupling the CTA interior ballistic model. Aiming at the interior ballistic characteristics of a CTA gun, the goal of CTA interior ballistic design is to obtain a projectile velocity as large as possible. The optimal design of CTA interior ballistic is carried out using a genetic algorithm by setting peak pressure, changing the chamber volume and gun powder charge density. A numerical simulation of interior ballistics based on a 35 mm CTA firing experimental scheme was conducted and then the genetic algorithm was used for numerical optimization. The projectile muzzle velocity of the optimized scheme is increased from 1168 m/s for the initial experimental scheme to 1182 m/s. Then four optimization schemes were obtained with several independent optimization processes. The schemes were compared with each other and the difference between these schemes is small. The peak pressure and muzzle velocity of these schemes are almost the same. The result shows that the genetic algorithm is effective in the optimal design of the CTA interior ballistics. This work will be lay the foundation for further CTA interior ballistic design.
文摘According to the compound packing problem in ammunition supply system in our army, the non-standard pallet series design model is proposed, and the original problem that can be solved as a set cover problem with a nested bin-packing problem, is analyzed, then two heuristic algorithms are applied to solve the problem.
文摘Security is a significant issue for everyone due to new and creative ways to commit cybercrime.The Closed-Circuit Television(CCTV)systems are being installed in offices,houses,shopping malls,and on streets to protect lives.Operators monitor CCTV;however,it is difficult for a single person to monitor the actions of multiple people at one time.Consequently,there is a dire need for an automated monitoring system that detects a person with ammunition or any other harmful material Based on our research and findings of this study,we have designed a new Intelligent Ammunition Detection and Classification(IADC)system using Convolutional Neural Network(CNN).The proposed system is designed to identify persons carrying weapons and ammunition using CCTV cameras.When weapons are identified,the cameras sound an alarm.In the proposed IADC system,CNN was used to detect firearms and ammunition.The CNN model which is a Deep Learning technique consists of neural networks,most commonly applied to analyzing visual imagery has gained popularity for unstructured(images,videos)data classification.Additionally,this system generates an early warning through detection of ammunition before conditions become critical.Hence the faster and earlier the prediction,the lower the response time,loses and potential victims.The proposed IADC system provides better results than earlier published models like VGGNet,OverFeat-1,OverFeat-2,and OverFeat-3.
基金the National Natural Science Foundation of China, ChinaGrant ID: 11472137。
文摘This paper focuses on the dynamic tracking control of ammunition manipulator system. A standard state space model for the ammunition manipulator electro-hydraulic system(AMEHS) with inherent nonlinearities and uncertainties considered was established. To simultaneously suppress the violation of tracking error constraints and the complexity of differential explosion, a barrier Lyapunov functionsbased dynamic surface control(BLF-DSC) method was proposed for the position tracking control of the ammunition manipulator. Theoretical analysis prove the stability of the closed-loop overall system and the tracking error converges to a prescribed neighborhood asymptotically. The effectiveness and dynamic tracking performance of the proposed control strategy is validated via simulation and experimental results.
基金The authors appreciate the laboratory assistance of Goran Simundic and Michael Goodwin for assistance with measurement of the field test results The assistance of final year honours student Richard Szlicht is gratefully acknowledged.
文摘The paper describes field test results of 7.62×51 mm M61 AP(armour piercing) ammunition fired into mild steel targets at an outdoor range.The targets varied from 10 mm to 32 mm in thickness.The tests recorded penetration depth,probability of perforation(i.e.,complete penetration),muzzle and impact velocities,bullet mass,and plate yield strength and hardness.The measured penetration depth exhibited a variability of approximately±12%.The paper then compared ballistic test results with predictive models of steel penetration depth and thickness to prevent perforation.Statistical parameters were derived for muzzle and impact velocity,bullet mass,plate thickness,plate hardness,and model error.A Monte-Carlo probabilistic analysis was then developed to estimate the probability of plate perforation of 7.62 mm M61 AP ammunition for a range of impact velocities,and for mild steels,and High Hardness Armour(HHA) plates.This perforation fragility analysis considered the random variability of impact velocity,bullet mass,plate thickness,plate hardness,and model error.Such a probabilistic analysis allows for reliability-based design,where,for example,the plate thickness with 95% reliability(i.e.only 1 in 20 shots will penetrate the wall) can be estimated knowing the probabilistic distribution of perforation.Hence,it was found that the plate thickness to ensure a low 5% probability of perforation needs to be 11-15% thicker than required to have a 50/50 chance of perforation for mild steel plates.Plates would need to be 20-30% thicker if probability of perforation is reduced to zero.
文摘As part of a research program, it was desired to better understand the impact of the rotating chamber alignment with the barrel throat on the precision and accuracy of a novel cased telescoped(CT) ammunition firing rifle. In order to perform the study, a baseline CT ammunition chamber which was concentric with a Mann barrel bore was manufactured. Additionally, six chambers were manufactured with an offset relative to the barrel bore. These chambers were used to simulate a misaligned chamber relative to the bore axis. Precision and accuracy tests were then performed at 200 m in an indoor range under controlled conditions. For this project, 5.56 mm CT ammunition was used. As the chamber axis offset relative to the gun bore was increased, the mean point of impact was displaced away from the target center. The shift in the impact location is explained by the presence of in-bore yaw which results in lateral throw-off and aerodynamic jump components. The linear theory of ballistics is used to establish a relationship between the chamber misalignment and the resulting projectile mean point of impact for a rifle developed to fire CT ammunition. This relationship allows for the prediction of the mean point of impact given a chamber misalignment.
基金the Army Scientific Research(KYSZJWJK1744,012016012600B11403).
文摘Aiming at the problem that the consumption data of new ammunition is less and the demand is difficult to predict,combined with the law of ammunition consumption under different damage grades,a Bayesian inference method for ammunition demand based on Gompertz distribution is proposed.The Bayesian inference model based on Gompertz distribution is constructed,and the system contribution degree is introduced to determine the weight of the multi-source information.In the case where the prior distribution is known and the distribution of the field data is unknown,the consistency test is performed on the prior information,and the consistency test problem is transformed into the goodness of the fit test problem.Then the Bayesian inference is solved by the Markov chain-Monte Carlo(MCMC)method,and the ammunition demand under different damage grades is gained.The example verifies the accuracy of this method and solves the problem of ammunition demand prediction in the case of insufficient samples.
文摘Euler angles and Euler kinematics equation of terminal sensing ammunition are expressed and rewritten by using quaternion to solve the singular problem in using Euler angles to describe the motion.The contrastive simulations are performed in order to validate the correctness and advantage of the quaternion description.The simulation results show that the dynamic model with quaternion have stable solution,there is not singular point in the calculation,and the ballistic model rewritten by using the quaternion is suitable for describing the terminal sensing ammunition's scanning motion than the common Euler equation.
文摘Some long distance air ammunition can be used to attack large still target. According to this character and according to the mathematical description of target-missile relative motion built by the message supplied by the strapdown inertial navigation system/global position system (SINS/GPS) of air ammunition, optimal guidance law is designed by applying optimal control theory. The simulation is provided to indicate that when the air ammunition reaches the target, its line-of-sight (LOS) and LOS angular rate can nearly equal zero. So the air ammunition can get good terminal attitude, and the air ammunition reaches the target at the expected velocity and heading.
基金supported by the Chinese PLA General Armament Department under Grant No.51318020305
文摘In recent years, microstrip antennas have been more widely applied in satellite communications, mobile phones, unmanned aerial vehicle (UAV), and weapons. A micro-electro-mechanical systems-based (MEMS-based) high-resistance silicon C-band microstrip antenna array has been designed for the intelligent ammunition. The center frequency is 4.5 GHz. A cavity has been designed in substrate to reduce the dielectric constant of silicon and high-resistance silicon has been used as the material of substrate to improve the gain of antenna. It is very easy to be manufactured by using MEMS technology because of the improved structure of the antenna. The results show that the gain of the antenna is 8 dB and voltage standing wave ratio (VSWR) is less than 2 by the analysis and simulation in high freauencv structure simulator (HFSS).
基金supported by the Natural Science Foundation of China(Grant number:NSFC11572095)。
文摘Safety of underground ammunition storage is an important issue,especially during the accidental ignition of missiles.This work investigates the pressure and temperature distribution of the multi-layer underground ammunition storage with a pressure relief duct during the accidental ignition process of the missile.A large-scale experiment was carried out using a multi-layered restricted space with a pressure relief duct to simulate the underground ammunition store and a solid rocket motor to simulate the accidental ignition of the missile.The results show that when the motor gas mass flow increased by5.6 times,the maximum pressure of the ammunition storage increased by 5.87 times.At a certain motor flow rate,when the pressure relief exhaust area at the end of the relief duct was reduced by 1/2,the maximum pressure on the first layer did not change.But the rate of pressure relief was reduced and the time delayed for the pressure of ammunition store to drop to zero.In this experiment,when the motor ignition position was located in to the third layer ammunition chamber,the maximum pressure was reduced by 32.9%and also reduced the rate of change of pressure.In addition,for the experimental conditions,the theoretical analysis of the pressure relief of the ammunition storage is given by a simplified model.Based on the findings,some suggestions to the safety protection design of ammunition store are proposed.
文摘The hard target smart fuse of penetration ammunition is developing to be smaller, lighter, smarter and multifunction. After analyzing the characteristics of high-g accelerating signals and the penetration algorithms, this paper provides a solution of penetration ammunition fuse system based on embedded technology. This fuse system realizes acquisition of the high-g accelerating signals and uses the appropriate penetration algorithms to process them. The fuse system can not only make the same type of penetration ammunition to attack different kinds of objects accurately, but also meet the other requirements of the function of penetration ammunition fuse system.
文摘Modern ammunition-rocket system is a complicated multidisciplinary system. During its development, undetermined factors will bring many risks. This paper elaborates the importance of risk analysis approach to ammunition-rocket system development and analyses various methods of risk analysis and estimation. Combined with practical situation of weapon system development, the risk measurement function with characteristics of risk preference is given provided that the risk preference characteristic of behavior maker is risk neutral of fixed constant. The development risk analysis based on risk measurement function enables effective risk decision to be made on the basis of quantified risk. Taking anti-helicopter intelligent mine warhead as an example, the paper verifies the efficiency of the method and shows that it has a scientific and practical value.
基金Sponsored by National Nature Science Foundation of China(70771038).
文摘For the gradual maturity of Bayesian survival analysis theory,as well as the defects of the traditional methods for storage reliability evaluation,the Bayesian survival analysis method is proposed to build regression models for reliability in the random truncated test.These models can reflect the influences of different environments on the ammunition storage lifetime.As an example,the common exponential distribution is used here,and Markov chain Monte Carlo(MCMC)method based on Gibbs sampling dynamically simulates the Markov chain of the parameters' posterior distribution.Also,the parameters' Bayesian estimations are calculated in the random truncated condition.The simulation results show that the proposed method is effective and directly perceived.