Table of Content

30 August 2019, Volume 40 Issue 8

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Contents

2019, 40(8):  0. 

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Paper

Theoretical Model and Numerical Study of Shaped Charge Jet Penetrating into Thick Moving Target

JIA Xin, HUANG Zhengxiang， XU Mengwen， XIAO Qiangqiang

2019, 40(8):  1553-1561.  doi:10.3969/j.issn.1000-1093.2019.08.001

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An attack mode using shaped charge jet is proposed to effectively intercept and destroy the incoming high-speed missiles and earth-penetrating projectiles with large wall thickness. Based on virtual origin theory, an infinitesimal method is used to divide the interaction process of shaped charge jet and thick moving target into two stages: undisturbed jet penetration and disturbed jet penetration. At the undisturbed jet penetration stage, the jet is not be disturbed by lateral force on target plate. The penetration depth contributed by undistributed jet and the aperture of cavity were analyzed. At the disturbed jet penetration stage, the jet is disturbed by lateral force on target plate. The models of lateral drift velocity and penetration depth of distributed jet were established. A 40 mm-diameter shaped charge was designed to verify the theoretical model. The penetration depth of jet penetrating into steel target at the transverse velocity of 0-600 m/s was calculated using the LS-DYNA software. The theoretical results of the proposed model were compared with the experimental data in Ref.\[17\]. The results indicate that the shaped charge warhead is an effective means to strike high speed moving target. The higher the moving speed of target is, the shorter the elapsed time at the undisturbed jet penetration stage is, the more the interference of jet is, and the smaller the penetration depth is. Key

Construction for Online Observer Based on Exhaust Gas Temperature Dynamic Model

LI Jiawei, CUI Tao, LIU Yuhang, SHI Shuainan, SUN Qiang

2019, 40(8):  1562-1571.  doi:10.3969/j.issn.1000-1093.2019.08.002

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As one of the most core components for diesel emission control and monitoring, the exhaust temperature sensor is widely used for electronic control of diesel engine. In order to satisfy the needs of on-line fault diagnosis and fault-tolerant control of rear temperature sensors for the two-stage turbocharging system, an engine is used to establish a dynamic model of exhaust gas temperature which reflects the combustion conditions of cylinder, and the air-fuel ratio, engine speed, and altitude are used to calibrate the exhaust gas temperature influencing factors virtually. An on-line exhaust gas temperature observer including first-order lagging links was constructed, and the effectivenesses of observer at steady state and dynamic situation were verified in typical operating conditions. The result shows that the on-line observer can be used for on-line temperature estimation, which has a high calculation accuracy and dynamic response performance with the steady state accuracy of ±3%, the dynamic accuracy of ±8%, and the response time of less than 3 s. Key

Energy Management of Hybrid Electric Tracked Vehicle Based on Off-road Condition Prediction

XU Shaohang, XI Junqiang, CHEN Huiyan

2019, 40(8):  1572-1579.  doi:10.3969/j.issn.1000-1093.2019.08.003

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An energy management system based on off-road condition prediction is designed for the energy management of hybrid tracked vehicle in off-road environment. The vehicle speed and attitude are measured by using the vehicular sensor, and the off-road condition is classified based on support vector machine. A speed prediction model based on Markov chain is established using historical driving speed and acceleration for different off-road conditions. A model predictive control strategy based on off-road condition prediction is designed for energy management of hybrid electric tracked vehicle. The simulated results show that the proposed energy management system can be used to achieve the control objectives and improve the performance of hybrid electric tracked vehicles in off-road environment. Key

Kinematic Analysis and Optimization of Key Parameters of Suspension for Electric Differential Steering Wheeled Amphibious Vehicle

JU Dongmei， XIANG Changle， TAO Yi， XU Xiaojun， WANG Wenhao

2019, 40(8):  1580-1586.  doi:10.3969/j.issn.1000-1093.2019.08.004

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In order to reduce the shape resistance of vehicles in water, it is necessary to raise the wheels of amphibious vehicles above the water line. A retractable suspension scheme for amphibious vehicles is proposed. Kinematics analysis is carried out to obtain the movement law of retractable suspension for vehicle. The optimization of suspension parameters is formulated to improve the retractable height of suspension. In the multi-body dynamics software ADAMS/Insight, the parameter optimization experiments are designed, and the optimization variables are determined by analyzing the sensitivity of parameters. According to the selected optimization variables, the optimization objectives are used to optimize the traveling mechanism, such as the receiving and unloading height, the turning angle, the camber angle and the kingpin inclination angle. The results show that the optimization effects of the retracting process and kinematics characteristics of the traveling mechanism are obvious, and the navigation resistance on water is greatly reduced while the land performance is guaranteed. Key

Analysis of Spin Rate and Correction ability of Two-dimensional Trajectory Correction Fuze for 155mm Fixed-canard Dual-spinProjectiles

SHI Kai， ZHANG Qian, LIU Mabao

2019, 40(8):  1587-1595.  doi:10.3969/j.issn.1000-1093.2019.08.005

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The premise of realizing the trajectory correction of two-dimensional trajectory correction fuze is to control the spin rate of fixed canards. Based on the 155mm fixed-canards projectile with two-dimensional trajectory correction fuze, the spin characteristics of projectile body and canards during dual-spinning are analyzed, respectively. A motion model of dual-spin stabilized projectile under the action of fixed canards is established. The two-dimensional trajectory correction fuze of 155 mm fixed-canard dual-spin projectile is simulated to calculate the aerodynamic parameters of canards by using CFD software. The dynamics equation of rolling channel is analyzed, and the characteristics of whole ballistic spin rate are analyzed from the following aspects: moment of inertia, moment of friction, rolling damping moment, and moment of canard guide roll moment. On the basis of spin rate control, the correction capability of two-dimensional trajectory correction fuze is evaluated. The simulated results show that 5.0-5.5 degrees of the rotating canards and 8-9 degrees of the modified canard can meet the requirement of balancing spin rate and the correction capability for control, and the simulated results of spin rate can represent the rotational speed characteristics of dual-spin-stabilized projectiles with course correction fuze and precision guidance kit. Key

Novel Bridgeless Igniter Based on Carbon Fiber Composites

YI Zhenxin, CAO Yaqing, ZHANG Lin, ZHU Shunguan, ZHU Chenguang

2019, 40(8):  1596-1602.  doi:10.3969/j.issn.1000-1093.2019.08.006

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Carbon-based energetic composite (CEC) was prepared by mixing the carbon fibers with lead azide (LA), lead styphanate (LS) and nickel hydrazine azide (NHA), respectively. The relationship between carbon fiber content and igniter performance was studied. The experimental result indicates that the ignition voltage of igniter is the lowest when the carbon fiber content is 30%. The 50% ignition voltages of NHA-CEC igniter, LS-CEC igniter and LA-CEC igniter are 14.1 V, 17.6 V and 27.8 V, and their safety currents are 280 mA, 250 mA and 180 mA ,respectively. The 50% electrostatic ignition voltages of NHA-CEC igniter, LS-CEC igniter and LA-CEC igniter are 28.9 kV, 27.3 kV and 30 kV, respectively, in pin-to-pin, and the antistatic capacity is more than 25 kV in pin-to-case of three type of igniters. The ignition process of igniter was investigated by high-speed photography and lead plate test of detonator. The results show that all the ignitors have reliable ignition ability, and LA-CEC and NHA-CEC can reliably detonate RDX to perforate the lead plate. The bridgeless pyrotechnics with CEC show more anti-electrostatic ability and are fabricated easily to the bridge wire and semiconductor bridge pyrotechnics. Key

Experimental Research on Energy Release Behavior of W/Zr/Hf Alloy Fragment

WANG Luyao, JIANG Jianwei, LI Mei, MA Yuyu

2019, 40(8):  1603-1610.  doi:10.3969/j.issn.1000-1093.2019.08.007

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To investigate the energy release behavior of reactive material under impacting conditions, a high-strength and high-density tungsten-zirconium-hafnium active alloy fragment is driven to impact the Q235 steel target at different speeds by a ballistic gun. A three-stage, including shock activation, self-propagation energy release, and secondary self-activation, model of impact-release energy of alloy fragments is proposed by observing the perforation pattern of steel target and the high-speed photographic image of the post-target impact-release fire zone.The activation threshold of fragment energy, the critical condition of complete energy release, the maximum size of energy release flare region and the effective damage distance behind the target were obtained by applying stress wave, thermal stress theory and shock temperature rise equation. The results show that the tungsten-zirconium-hafnium active alloy fragment not only has the kinetic energy damage ability similar to the inert fragment, but also has a little active energy consumption before the target is penetrated, and the active energy is completely released in a millisecond time regime after penetrating into the target. Before the fragmentation active energy is fully activated, the maximum damage volume and effective damage distance in the release energy flare region increase exponentially and linearly with the increase in fragmentation speed. Key

Effect of Fluororubber Coating on the Properties of Nano-aluminum Powders

YAN Tao, REN Hui, MA Ai'e, JIAO Qingjie, WANG Huixin

2019, 40(8):  1611-1617.  doi:10.3969/j.issn.1000-1093.2019.08.008

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In order to obtain the influence of coating layers on the properties of nano-aluminum powders, the nano-aluminum powders prepared by the electric explosion method are coated with 5%, 10% and 15% of fluororubber. The surface morphologies, coating thicknesses, specific surface areas, elemental valence states and thermal responses of modified nano-aluminum powders are characterized using scanning electron microscope, transmission electron microscope, physical adsorption analyzer, X-ray photoelectron spectrometer and simultaneous thermal analyzer. And the active aluminum contents and combustion heat of different samples were measured. The results show that the specific surface areas of the modified nano-aluminum powders are slightly large than that of the passivated nano-aluminum powders. Fluororubber coatings chemically adsorb on the surface of nano-aluminum powders, which enhances the thermal stability of nano-aluminum powders, prevents the aluminum powders from further oxidation, and makes one of the contents of active aluminum up to 85.85%. The fluororubber promotes the combustion of modified nano-aluminum powders, so that the combustion heat of the modified nano-aluminum powders is more than that of the passivated nano-aluminum powders. Key

A System-level Calibration Method for Laser Gyro SINS

DONG Chunmei， REN Shunqing， CHEN Xijun， LI Wei

2019, 40(8):  1618-1626.  doi:10.3969/j.issn.1000-1093.2019.08.009

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An exciting method of rotating the turntable outer axis for an integer period is designed to optimize the system-level calibration method of calibrating a strapdown inertial navigation system (SINS) on the horizontal three-axis turntable. Based on the SINS error equation, the relationships among velocity errors and inertia measurement unit (IMU) errors are described, and a system-level calibration model of IMU is established. In the proposed model, the interaction effect of error parameters of accelerometer and gyro is avoided due to that the northward component contains the accelerometer errors and the eastward component contains the gyro errors only. According to the quasi-D optimal criterion, a 12-point plan of the icosahedron is designed, and 24 error terms of IMU are identified by least square method when one axis runs in the speed mode and the other axes run in the position mode. The simulated results show that the influences of the accelerometer and gyro measurement noises on the system-level calibration results are effectively restrained, and the error terms are identified accurately. Key

Research on GNSS Satellite-ground Service Information Transmission Scheduling Method Based on Inter-satellite Link

SONG Weilin， YANG Daoning

2019, 40(8):  1627-1633.  doi:10.3969/j.issn.1000-1093.2019.08.010

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The inter-satellite link is one of the main technical features of modern satellite navigation systems. A scheduling mathematical model is designed for the service information transmission scheduling problem of satellite navigation system with inter-satellite link. Based on this, a heuristic scheduling algorithm is proposed. Based on scene settings of Beidou-3 satellite navigation system, the model and algorithm are simulated and verified. The simulated results show that the proposed method can be used to schedule the service information transmission of 30 satellites in the satellite navigation system under the condition of regional monitoring network consisting of three ground stations in Beijing, Xinjiang and Hainan. And the scheduling results satisfy the mission requirements of satellite navigation system. The average number of ground station antennas is 15.375 in each mission period, and the utilization rate of most ground station antennas is over 70%. Key

Research on the Expansion and Fracture Characteristics of Drawing-molded Oxygen-free Copper Tubes under Detonation Loading

SHEN Fei, WANG Hui, LI Biaobiao, ZHANG Gao

2019, 40(8):  1634-1640.  doi:10.3969/j.issn.1000-1093.2019.08.011

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In order to explore whether the drawn-molded oxygen-free copper tube meets the ductility requirements of standard cylinder test, a standard copper tube for SymbolFA@25 mm cylinder test was made of coarse-grained soft oxygen-free copper without secondary forging by using the drawing process. The high-speed framing camera and scanning camera were used to observe the expansion and fracture processes of copper tube under detonation loading of TNT and JO-159 explosives, and compare the difference of fracture strain and the direction of crack propagation in the typical high strain rate range. The influence of strain energy of copper tube on the characterization parameters of driving performance of explosive was also analyzed. The results show that the cracks of copper tubes are mainly formed and expanded along the busbar and the fragments are mainly strip-like under the detonation loading of TNT explosive. However, under the detonation loading of JO-159 explosive, a more complicated staggered state arises in the fracture zone, and the copper tube expands to form dense small fragments. The main reason for this phenomenon is that the circumferential and axial strain rates of copper tubes under detonation loading of JO-159 explosive are 1.34 and 2 times of those under detonation loading of TNT. Under the detonation loading of these two kinds of explosives, the fracture diameter reaches 3 times of the initial diameter, and the Gurney speed, which characterizes the driving performance of explosives, is not changed significantly. Therefore, the copper tubes can meet the requirements of the general high-energy explosives for cylinder test. Key

Comparison of Long-wave Infrared Interferometric Spectral Imagers and Design of Variable Gap F-P Type Spectral Imager

MENG Hemin， GAO Jiaobo， WANG Nan， WU Jianghui， GAO Zedong， ZHAO Yujie， LIU Fang

2019, 40(8):  1641-1647.  doi:10.3969/j.issn.1000-1093.2019.08.012

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Long-wave infrared (LWIR) spectral imaging technology has broad application prospects in mineral detection and identification of hazardous chemicals. Five kinds of common interference spectral imagers, such as two-sided Sagnac type, three-sided Sagnac type, static Michelson type, swing arm Michelson type and variable gap Fabry-Perot (F-P) type, are analyzed for the miniaturization and multi-platform application of LWIR spectral imaging technology. The advantages and disadvantages of these imagers are analyzed from the aspects of volume, stability, accuracy requirements, and optical system complexity. A prototype of variable gap F-P spectral imager was developed. The rearrangement, apodization, Fourier transform, spectral radiation calibration and other processing methods are used to accurately invert the target spectrum. The chemical DMMP was tested using the prototype imager, and the test result is consistent with that of MR170 high precision spectrometer. Key

Adaptive Dynamic Indicators Configuration Method for Dealing with Electromagnetic Interference in Battlefield

WU Tianhao， WANG Jingsong， NIU Kan， SUN Miao， WU Shaoqiang

2019, 40(8):  1648-1657.  doi:10.3969/j.issn.1000-1093.2019.08.013

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In the confrontation between friend and foe, the continuous electromagnetic conflict and interference may lead to the decrease in operational effectiveness or even functional loss of equipment. How to achieve rapid response and accurately configure the components and parts parameters in the electromagnetic interference environment has become one of the key capabilities to win the modern war. According to the uncertain, dynamic and multi-dimensional characteristics of battlefield electromagnetic interference, an adaptive dynamic indicator configuration method based on grey bullseye decision theory is proposed for the decision-making environment with unknown index weights and time sequence weights. Taking the approaching degree as a measurement standard, an adaptive grey target decision model with multiple time intervals is given vertically, and the adaptive adjustment method of the acquisition interval timing is given horizontally to realize the adaptive adjustment and determination of the countermeasure indicators. A adaptive dynamic indicators configuration model is constructed based on the type and principle of battlefield electromagnetic interference. The experiment and simulation were made, and the calculated results of the proposed algorithm was compared with those of the standard algorithm. The simulated results show that the proposed algorithm is feasible and accurate. Key

Design of Static Spectral Polarization Imaging System with Double Wollaston Prism

ZHAO Yiwu, DUAN Yun, LI Yingchao, SHI Haodong, JIANG Lun, WANG Chao, LIU Zhuang, LI Guanlin

2019, 40(8):  1658-1664.  doi:10.3969/j.issn.1000-1093.2019.08.014

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A static spectral polarization imaging system based on double Wollaston prism is proposed for the complex structure or moving parts of traditional spectral polarization imaging systems. According to the Stokes spectral modulation theory, a static spectral polarization imaging system with dual Wollaston prism is designed by using the polarization characteristics and beamsplitting principle of double Wollaston prism. The image side telecentric design is used for the pre-telescope system, and the object side telecentric design is used for the post-spectral polarization splitting system to achieve pupil matching. The whole structure adopts a spherical mirror and has no moving parts. It can simultaneously acquire the spectral and polarization information of target. The operating wavelength of the system is 450-900 nm, the focal length is 275 mm, the aperture is 90 mm, and the field of view is 2.35°. The analysis results show that full-field-of-view modulation transfer function (MTF) of the system is better than 0.55 at the Nyquist frequency of 90 lp/mm, and the imaging quality is close to the diffraction limit, which satisfies the imaging requirements.Key

Research on Electro-optical Composite Detection Mechanism Based on Microchannel Active Substrate

MU Yining, CHEN Xuewei, LIU Chunyang, LIU Dexing, HAO Guoyin

2019, 40(8):  1665-1672.  doi:10.3969/j.issn.1000-1093.2019.08.015

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A detection mechanism that can realize the composite detection under extremely weak light condition is proposed in order to meet the needs of composite detection in military and aerospace fields. The operating principle of a new device is described based on the photomultiplier model of microchannel plate, and the effect of transmission anode of complex waveguide anode on the constraints of vacuum photomultiplier system is analyzed. The device characteristics of the complex waveguide anodes are investigated using the analytical method of modulation transfer function. The feasibility of the scheme was proved by verifying the relevant parameters of composite waveguide anode. Based on the verification of the composite anode, a composite waveguide gate is proposed to improve the performance of composite detection, research the membrane for separating electric current, and simulate the electronic trajectory. The new device was test in a vacuum furnace. The results show that the device can extract two signals from a beam of incident light, and compared with the composite anode, the resolution of the composite gate device with composite gate is doubled. Key

Route Optimization Strategy of Military Cooperative Inspection

HAN Yuxing, DING Gangyi, CHAI Zuohong

2019, 40(8):  1673-1679.  doi:10.3969/j.issn.1000-1093.2019.08.016

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An improved cooperative ant colony optimization algorithm is proposed to enhance the inspection efficiency of large-scale inspection system with multiple robots. Each robot has an ant colony to search its inspection path, and a sharing taboo list is designed to implement the information interaction among the different ant colonies. The cost competitive mechanism is used to determine an ant among different ant colonies to search the inspection node. According to the distribution of the inspection nodes, the cooperative ant colony optimization algorithm could be used to accomplish the region segmentation and the path optimization simultaneously. Thus the inspection region could be segmented reasonably. Experimental results show that the cooperative ant colony optimization algorithm could be used to segment the inspection task more evenly than the conventional method based on map segmentation, which enhances the utilization rate of inspection robots, and the total inspection workload could be reduced. Therefore, the inspection performance could be improved significantly. Key

A Design of an Orthogonal Set of Transmitting Waveforms of MIMO Sonar Based on Costas Sequence

JIA Jidong, LI Shuqiu, GAO Shanguo

2019, 40(8):  1680-1687.  doi:10.3969/j.issn.1000-1093.2019.08.017

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It’s important to find an orthogonal set of transmitting waveforms of MIMO sonar, and the orthogonality of signal set has a direct affect on the detection efficiency of MIMO sonar. The frequency-hopped signal based on a Costas sequence has a nearly ideal range-Doppler ambiguity function, however, the different frequency-hopped signals constructed by different primitive elements of a finite field are not always orthogonal. A search method for primitive elements is proposed based on the finite field theory, and an optimal orthogonal set of transmitting waveforms is designed based on the primitive elements of safe primes. The simulated results show that a set of transmitting waveforms made from a safe prime, which is less than 1 000, has not only the best orthogonality but also the maximum number of signals. Key

Acoustic Information-based TMA Method for Uniformly Accelerating Motion of Target

JU Yang， YUAN Yonghu， LIN Wei， XU Haisheng

2019, 40(8):  1688-1692.  doi:10.3969/j.issn.1000-1093.2019.08.018

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The most research on target motion analysis (TMA ) of underwater target is based on the hypothesis of uniform motion of a target, but is seldomly based on the hypothesis of uniformly accelerating motion. An innerpoint-Levenberg-Marquard (LM) method of calculating TMA parameters without the motion of observation platform is proposed. And an optimization searching method for TMA parameters is proposed, which combines the Doppler effect double model and the solving method of TMA parameters. It makes the solving process of parameters converge quickly. Simulated result shows that the inner-point LM method can be used to solve the TMA parameters effectively and reduce the dependence on the motion observation platform. Key

A Dynamic Camouflage Effect Evaluation Method Based on Feature Statistics

YANG Xin, XU Weidong, JIA Qi

2019, 40(8):  1693-1699.  doi:10.3969/j.issn.1000-1093.2019.08.019

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The existing camouflage effect evaluation is mainly for a single still image, which can not simulate the process of the reconnaissance personnel's interpretation of a target. A feature statistics-based dynamic camouflage effect evaluation method is proposed based on mean shift target tracking algorithm. The proposed method is to establish a normalized joint Gaussian distribution by using the data of correlation features between the target and the background of eight-way domain, and use the distribution range of probability density to evaluate the camouflage effect of target. A logarithmic amplification probability is proposed for calculating the probability density of joint distribution, which solves the problem that the high-dimensional joint distribution probability density has low numerical sensitivity and is inconvenient to set a threshold. At the same time, a sample update strategy is introduced to make the sample library update randomly according to a certain probability, so as to better adapt to the change in large-scale background caused by the turn of seasons and other factors. In the experimental process, the first-level, second-level and third-level camouflages are applied to a certain command vehicle. After collecting the data, the logarithmic amplification probability is calculated, and the statistics on the curves is made. The results show that 3 camouflages divided in reality completely correspond to the first-level，second-level and third-level camouflages pre-set by the 3σ criterion. The experimental results show that the model can effectively reflect the camouflage effect of target. Key

Design and Stability Analysis of Cantilever Low Pressure Casting Machine

LIU Zhigang, AN Jianfei, SHI Xiaoping, PEI Chenghui, HUANG Dongnan, WEN Haijun

2019, 40(8):  1700-1707.  doi:10.3969/j.issn.1000-1093.2019.08.020

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The operating space of four-column low-pressure casting machine is very narrow, so it is inconvenient for the production of cavity castings with multi-openings and sand cores. A low pressure casting machine with main and auxiliary cantilevers which swing synchronously and the completely opened space above the worktable was designed. The forces acting on the main cantilever during the filling, holding and unloading stages of the castings were calculated by using the relevant knowledge of fluid mechanics. The maximum impact force is 35 302 N, and the maximum gravity is 4 606 N. According to the maximum clearance between the upper mold and the side mold, the main cantilever is made of Q235A hollow round steel with length of 1 200 mm, outer diameter of 270 mm and inner diameter of 235 mm. The finite element method was used to simulate and analyze the cantilever structure. The results show that the maximum deformation is 1.8 mm at the oil cylinder of upper die of cantilever. The cantilever low pressure casting machine prototype was test, which meets the performance requirements of military products. When the caster enters the packing stage, the distance between the upper mold and the side mold is 1.92 mm, which is within the allowable safety clearance. Key

Location-allocation Joint Optimization Model of Spare Parts Supply under Supply Disruption Risk

WANG Yadong, SHI Quan, CHEN Cai, YOU Zhifeng

2019, 40(8):  1708-1715.  doi:10.3969/j.issn.1000-1093.2019.08.021

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In wartime, the spare parts warehouse or transport carrier may be attacked deliberately, and some storage and transportation capacity may be completely or partially lost, which leads to the interruption of spare parts supply system. The interruption risk of supply network is an uncertain parameter and difficult to be predicted and change dynamically. In view of the depth uncertainty of interruption risk, the diversification of wartime spare parts supply optimization objectives is considered. A joint optimization model of multi-objective location-allocation for wartime spare parts supply is constructed for the minimum cost of spare parts supply and the shortest lead time of supply. A corresponding robust optimization model is established based on the robust equivalent change of polyhedron uncertainty set. The meta-heuristic algorithms are used to obtain the non-dominate solution sets and the corresponding supply plans. The results show that the efficiency and reliability of spare parts supply network can be greatly improved by strengthening some key nodes. On the other hand, the optimal solution of the robust optimization model can guarantee the feasibility of the worst-case solution of spare parts supply, that is, the model has good robustness. Key

Demand Forecasting Model for Joint Fire Strike Ammunition under Stochastic Combination Constraints

XUE Hui， WANG Yuan， ZHANG Tianpeng， LIU Tielin

2019, 40(8):  1716-1724.  doi:10.3969/j.issn.1000-1093.2019.08.022

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For the ammunition demand forecast under joint firepower strike, the effective combat effectiveness indexes of different equipment against different targets are determined based on the loss-exchange ratio of weapon-equipment confrontation. The effective combat effectiveness index is taken as a criterion to evaluate the threat of enemy targets to friend equipment, and provide an essential basis for ammunition demand forecasting. According to the principle of maximum damage to enemy, an joint firepower strike ammunition demand forecasting model with the maximum comprehensive combat effectiveness index as the objective function is established. A variety of constraints are set according to the influencing factors of ammunition demand, the constraints are randomly combined according to the actual combat situation, and the intelligent optimization algorithm is used to solve the model. The result shows that the proposed method is reasonable, effective and operable, and represents the characteristics of joint firepower strike. The demand forecasting of joint fire strike ammunition under the optimal equipment-ammunition-target formation mode is realized. Key

Microphone Array Sound Source Direction-of-arrival Estimation Based on Distributed Compressed Sensing

HUANG Huixiang， GUO Qiuhan， TONG Feng

2019, 40(8):  1725-1731.  doi:10.3969/j.issn.1000-1093.2019.08.023

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Compressed sensing-orthogonal matching pursuit (CS-OMP) algorithm is to transform the sound source localization problem into a signal sparse reconstruction problem, which can obtain higher positioning performance than the traditional positioning algorithm. However, the CS-OMP algorithm does not consider the correlation of multiple signals in positioning. The distributed compressed sensing (DCS) theory is introduced into the sound source localization of microphone array. Considering the common sparsity between the signals, the distributed compressed sensing-simultaneous orthogonal matching pursuit (DCS-SOMP) algorithm is used to reconstructure the signals for constructing a sparse position and positioning the sound source. Simulated and experimental results show that the DCS-SOMP algorithm has better positioning performance and robustness in low SNR environment compared with the traditional positioning algorithm and CS-OMP algorithm. Key

Event Triggered Adaptive Robust Trajectory Tracking Control for Multi-joint Manipulators

QIAN Qian, ZHANG Aihua, SUN Yixia

2019, 40(8):  1732-1739.  doi:10.3969/j.issn.1000-1093.2019.08.024

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For the multi-joint manipulator trajectory tracking control with uncertain disturbances and modelling errors, an event triggered controller is proposed based on adaptive robust control algorithm. The adaptive robust control algorithm is presented to ensure the trajectory tracking precision of multi-joint manipulator, and the adaptive term is used to deal with the uncertainty caused by uncertain disturbances and modelling errors. In the event triggered control framework, the current tracking errors and expected states are taken as inputs to define the state variables of event triggered control system, and Lyapunov stability theory is used to obtain the triggering condition,and no Zeno behaviours occur in the system. The control command is updated only when the triggering condition is satisfied, which can reduce the frequency of communication and computation, and improve the reliability. The semi-global uniform ultimate boundedness of multi-joint manipulator tracking control system is ensured, and the theoretical results are verified through simulation. Key

Research Notes

Research on Extreme Learning Machine Model-based Particle Filter Tracking Method for Device-free Localization

GUO Yonghong, SONG Biao, ZHAO Dongyang, LI Xuguang, NAN Huailiang

2019, 40(8):  1740-1746.  doi:10.3969/j.issn.1000-1093.2019.08.025

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Device-free localization (DFL) is an emerging wireless technique for estimating the location of target. The radio frequency signal is seriously polluted due to the uncertainty of wireless channel. An extreme learning machine model-based particle filter (ELM-PF) algorithm for DFL is proposed. The proposed algorithm is used for ELM building （offline stage）and target position estimation (online stage). In the ELM building process, a radio frequency signal propagation model built by ELM is used to describe the mapping relationship between target position and radio signal strength indicator (RSSI). In the process of target position estimation, a target is tracked via particle filter with the radio frequency signal propagation model. Experimental results show that the proposed ELM-PF algorithm can eliminate the fluctuation of the wireless signals and be robust to the tracking accuracy compared with the existing Gaussian process model-particle filter (GPM-PF) and support vector machine-particle filter (SVM-PF). Key

Design and Experimental Study of Ultrasonic Local Resonance System

LI Pengtao， ZHAO Bo， ZHAO Chongyang， WANG Yi

2019, 40(8):  1747-1755.  doi:10.3969/j.issn.1000-1093.2019.08.026

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In ultrasonic vibration machining, the cutting force and cutting heat are significantly reduced, the tool wear is reduced, and the machining efficiency is improved. The ultrasonic vibration machining process is widely used for machining the difficult-to-machine materials, such as hard and brittle materials. In order to avoid the influence of tool load on the resonant frequency, the local resonance theory is used to divide the vibration system into two subsystems. The frequency equation of complex acoustic system is derived from the total input impedance equal to zero at the junction of the subsystems, and the size of vibration system is calculated. Calculated results show that the modal analysis results and the actual measured results are less than 3% deviation from the theoretical values, which meets the design requirements and verifies the correctness of the theoretical design of local resonance. The acoustic system designed by this method is not affected by the tool load, the fluctuation of force during processing is small, and the stability of the system is improved to some extent, indicating that the local resonance system has a good processing effect. Key

Evaluation Method of Exponential Series System Reliability Based on Fixed Time Truncated Test and the Combinationof System and Its Units Test Data

JIN Junkun, YANG Ningguo, L Dongxue

2019, 40(8):  1756-1760.  doi:10.3969/j.issn.1000-1093.2019.08.027

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The test data of system and its units are provided through the reliability test of weapon. At the stage of approval test, the common evaluation method is to take the system test time into account but not considering the units test time, and the failure number in units test is either added directly into the total failure number (very severe but unscientific) or discarded (information waste). Based on the reliability model of exponential series system, the failure number and total time of units test are converted into the equivalent failure number and time of system by introducing the approximation formula of fiducial probability density of failure rate under fixed time truncated test scheme. The result indicates that the units test data can be used to supplement the system test data, reduce the cost of test, and improve the evaluation accuracy of reliability. The result also shows that the conversion formula of units data of fixed number truncated test is different from that of fixed time truncated test, and applying mechanically the conversion formula of fixed number truncated test is not worth advocating for the fixed time truncated test. Key