Table of Content

30 June 2016, Volume 37 Issue 6

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Paper

Research on Average Temperature Rise Characteristic of Wet Clutch

MA Biao, CHEN Fei, LI He-yan, XIONG Cen-bo, WANG Yu-sen, LI Geng-biao

2016, 37(6):  961-968.  doi:10.3969/j.issn.1000-1093.2016.06.001

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On the basis of the lumped parameter method which simplifies the components in hydraulic system to nodes, a thermal resistance network model of clutch hydraulic system is proposed to investigate the effects of oil flow and rotation speed difference on the temperature rise of wet clutch during engaging. An experimental device is designed to validate the simulation results. The results show that the oil flow rate has a greater influence on the temperature rise of wet clutch under the condition of high heat flux than that under the condition of low heat flux. The oil flow brings a slight effect on the temperature rise when the cooling flow increases to the critical value. Both the relative speed and the pressure have an influence on heat flux. The temperature of wet clutch is a linear function of the relative speed of friction plates. The clutch temperature rises by 8.05 percent with every 100 r/min increment in the relative speed under same cooling condition. The proposed model is verified effectively by comparison of simulated results and experimental data, which can better reflect the thermal equilibrium of wet clutch hydraulic system in normal condition.

Research on Parameter Updating of High Mobility Tracked Vehicle Dynamic Model Based on Multi-objectiveGenetic Algorithm

WANG Qin-long， WANG Hong-yan， RUI Qiang

2016, 37(6):  969-978.  doi:10.3969/j.issn.1000-1093.2016.06.002

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A method of model parameter updating is researched to improve the accuracy of simulation results of high mobility tracked vehicle dynamic model. A dynamic model of high mobility tracked vehicle is established, and the cement road and the gravel road are selected for updating the model parameters according to the statistical regularity of the driving conditions. The simulation results of dynamic model without parameter updating and the corresponding real vehicle test results under the same driving conditions are compared and analyzed, and the expression of objective function for model parameter updating is given. The updating parameters which influence objective function strongly are screened by using orthogonal experiment design method. The radial basis function neural network approximation models about the relation among updating parameters and objective functions are established to solve the issues of large calculation quantity and inefficiency of parameter updating. By analyzing the change rule of objective functions with updating parameters, the dynamic model parameters are updated simultaneously by using the second non-dominated sorting genetic algorithm (NSGA-Ⅱ) for two driving conditions. The final results of parameter updating are obtained. The research results show that the simulation accuracy of high mobility tracked vehicle dynamic model is effectively improved, and the availability of the proposed method is validated.

S Transform Relative Spectrum Entropy and Its Application in Degradation State Identification of Hydraulic Pump

WANG Yu-kui, LI Hong-ru, HUANG Zhi-jie, ZHAO Xu-cheng

2016, 37(6):  979-987.  doi:10.3969/j.issn.1000-1093.2016.06.003

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In order to characterize the degradation state of hydraulic pump, the degradation feature extraction method and degradation state identification method are studied. The degradation feature extraction method for pump which is named S transform relative spectrum entropy (STRSE) is proposed based on S transform (ST) for analyzing non-stationary vibration signal and relative entropy (RE)for characterizing the probability distribution difference among different signals. The analysis results of simulation signal demonstrate the availability and rationality of the proposed ST relative energy spectrum entropy (STRESE) and ST relative singular spectrum entropy (STRSSE) used as degradation features. The degradation feature vector is composed of the two features. The practical vibration signals of pump with piston shoe wear-out and loose faults are analyzed, and the results demonstrate the effectiveness of the proposed two features. The weighted grey relation method is used in the pump degradation state identification. A standard degradation mode matrix is built, and the degradation feature vectors of the samples to be identified are extracted. The grey relational analysis of degradation feature vectors and standard degradation mode matrix are performed. The grey correlation degrees are used to judge the degradation state of pump, and the analysis results demonstrate the favorable performance of the proposed method.

Analysis of Progressive Damage of Composite Housing for Railgun under Winding Prestress

YIN Dong-mei, LI Bao-ming

2016, 37(6):  988-995.  doi:10.3969/j.issn.1000-1093.2016.06.004

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A 3D progressive damage model based on Hashin’s failure criterion and progressive damage theory is established to study the failure mechanism of filament-wound housing for railgun barrel by using finite element method. The simulations predict the onset and evolution behavior of damages in the composite housing for railgun. The prestress based on the filament winding pattern with iso-hoop stress is calculated by referencing the design theory for filament-wound pressure vessels. And the effect of winding prestress on the progressive damage of the filament-wound housing is also analyzed. The results indicate that several damage modes, such as matrix crack and delamination, etc, occur in the composite housing. The matrix crack and delamination damages caused by tension are the main damage modes in the process of steady failure. Some damage modes are inhibited to some extent by winding prestress, while the damage of the whole composite housing is intensified by it. In addition, the winding pattern used in this paper can only improve the stiffness and sealing property of the bore at applied initial electromagnetic pressure.

Analysis and Application Research on Baseband Code Characteristics of Inductive Setting System for Smart Ammunition

CHANG Yue, SHEN Xiao-jun, LI Jie, HU Jun-ming, ZHANG Feng

2016, 37(6):  996-1005.  doi:10.3969/j.issn.1000-1093.2016.06.005

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In order to meet the requirements of large amount of data, high transmission rate, high reliability of smart ammunitions, and realize the data setting of smart ammunitions, 6 baseband coded formats, such as unipolar non-return-to-zero code, unipolar return-to-zero code, Miller code, Manchester code, mark inversion code and modified miller code, are theoretically analyzed and simulated from three aspects of inductive setting system, such as energy transmission efficiency, power spectrum and bandwidth, and the influence of symbol synchronization on bit error rate, and are compared with the experimental results. The simulation and experimental results show that the modified Miller code with low level gapfactor=0.3 has the better energy transmission efficiency, abundant clock timing information, and lower bit error rate, and it is suitable for the transmission channel; the Manchester code is a kind of self-synchronous phase encoding code, which has a relatively rich clock timing information and a very low bit error rate, and it is suitable for the feedback channel. The laboratory experimental results are consistent with the theoretically simulated results.

Numerical Simulation on the Unsynchronized Discarding of Sabots at Non-zero Angles of Attack and Sideslip

HUANG Zhen-gui, TANG Qi-zhong, CHEN Zhi-hua, ZHAO Qiang

2016, 37(6):  1006-1015.  doi:10.3969/j.issn.1000-1093.2016.06.006

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The investigation on the dynamics process of launch of ammunition under different conditions is important for improving its performance during design and contributes to adapt the complex variable modern battlefield for the ammunition. For the purpose of improving the firing accuracy and flight stability of an armour-piercing fin-stabilized discarding sabot, the sabot dynamic discarding behavior after the projectile being ejected from the muzzle at non-zero angles of attack and sideslip is simulated by coupling the computational fluid dynamics and the six degree of freedom exterior ballistic code through the unstructured dynamic mesh technique and user defined function. The flow field characteristics and the trajectory parameters of all sabots are obtained. In addition, the aerodynamic coefficients of projectile are also obtained. The numerical results show that the asymmetric flow field of the sabots can be observed under the influence of the asymmetric inflow. This will lead to the nonuniform distribution of pressure on the sabot surfaces. The different trajectories of three sabots appear due to the unsynchronized and asymmetrical discarding of sabot. The increased aerodynamic interference between projectile and sabot reduces the firing accuracy and flight stability of projectile.

Experimental Research on Behavior of Active Material Projectile with Steel-like Density Impacting Aluminum Target

XIAO Yan-wen, XU Feng-yue, YU Qing-bo, ZHENG Yuan-feng, WANG Hai-fu

2016, 37(6):  1016-1022.  doi:10.3969/j.issn.1000-1093.2016.06.007

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The ballistic impact experiments are performed to investigate the penetration behavior of the pressed and sintered PTFE/Al/W active material projectile with steel-like density impacting an aluminum target. Based on the experimental results of ballistic limit velocity, perforated patterns and average hole sizes produced by the cylindrical active material projectiles normally impacting 2A12 aluminum plates with different thicknesses, a semi-empirical relationship between the ballistic limit velocity and aluminum plate thickness is developed by combining with the THOR penetration equation. The effect of aluminum plate thickness on penetration behavior and performance of active material projectile are analyzed. Moreover, for the combined considerations of the pressure distribution in the active material projectile, the rarefaction wave effect and the impact-initiated delay time, the influence of active material chemical response on the penetration performance is analyzed and discussed . The analysis shows that the initiation efficiency and the deflagration pressure inside penetration hole are increased with the increase in target thickness, resulting in the significantly improved perforation ability of active material projectile at the end of the penetration hole.

Research on Effect of Al on Curing Property of GAP Spherical Propellant by Rheological Isothemal Measuring Method

HE Wei, HE Li-ming, MA Zhong-liang, XIAO Zhong-liang, GUO Yan-li

2016, 37(6):  1023-1029.  doi:10.3969/j.issn.1000-1093.2016.06.008

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In order to study the effect of Al on the curing process of glycidyl azide polymer (GAP) spherical propellant, the curing kinetics of GAP spherical propellant is studied by rheotogical isothermal measurement. Cuing parameters are obtained through Sestak-Berggren model, and the curing models of GAP spherical propellants with 0% Al and 10% Al are established. The results show that the apparent activation energy of GAP spherical propellant during cuing is less changed in the range of 0

A Guidance Law with Finite Time under Control Variable Constraint

DUAN Mei-jun, ZHOU Di

2016, 37(6):  1030-1037.  doi:10.3969/j.issn.1000-1093.2016.06.009

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Based on control theory with finite time convergence, the finite time convergence condition of Bang-Bang sliding-mode guidance law and a hysteresis control switch are proposed for the problem of that a kinetic kill vehicle intercepts a supersonic maneuvering target in near space. The condition of finite time convergence of the sliding-mode guidance law against maneuvering target under control variable constraint is presented based on the principle of nullifying the line-of-sight angular rate. Both planar guidance law and three-dimensional guidance law are designed. The upper and lower thresholds of hysteresis control switch are obtained to eliminate the chattering of line-of-sight angular rate. Simulation results show that the proposed guidance law ensures the finite time convergence of line-of-sight angular rate, and has higher guidance accuracy and robustness to high speed maneuvering target. The hysteresis control switch can remove the chattering of line-of-sight angular rate effectively.

Research on Efficiency of Additional Thrust of Thermal Launching

DENG Ke, ZHOU Cheng-kang, YU Dian-jun, JIANG Yi

2016, 37(6):  1038-1043.  doi:10.3969/j.issn.1000-1093.2016.06.010

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In order to study the increased thrust of thermal launching missile, three different exhaust spaces are designed, and the governing equations for simulating the thermal launch process of missile and a region-wide structured grid model of missile are established using CFD method. Second-order upwind scheme and fully implicit method are used for spatial discrete and time discrete, respectively. The process and velocity of missile exiting from launch tube in three different exhaust spaces are calculated. The aerodynamic characteristics of missile and the changing process of increased thrust for the motion of missile in launcher are analyzed. The numerical results are consistent with the experimental results. The results show that the exhaust space can be changed to achieve the re-use of gas energy, and convert the aerodynamic force to a thrust for missile motion in order to improve the velocity of missile and reduce the energy consumption of missile launching.

Research and Experiment of Pointing/acquistion/tracking System for Airborne Space Laser Communication

LI Xiao-ming， ZHANG Li-zhong， MENG Li-xin， SONG Yan-song， JIANG Hui-lin

2016, 37(6):  1044-1051.  doi:10.3969/j.issn.1000-1093.2016.06.011

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Airborne space laser communication is characterized by high speed, anti-electromagnetic interference, security and easy assignment. It has been applied in the areas of integrated space-ground communication, networking communication, military communication, reliable communication in anti-electromagnetic environment. The characteristics of airborne laser communication and Y-12 plane are analyzed for aligning the communication optical-axis on airborne platform. Two-stage tracking technology is used to design an airborne pointing, acquisition and tracking (PAT) system for laser communication , which consists of coarse and fine tracking units. The long distance communication experiment of the system carried by Y-12 planes is accomplished. The experiment proves the tracking performance and adaptability of the PAT system.

The Application of Normal Distribution Transformation Algorithm in Sonar Image Processing

TAN Ke， ZOU Li-na

2016, 37(6):  1052-1057.  doi:10.3969/j.issn.1000-1093.2016.06.012

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For the requirements of the real-time processing of sonar image matching processing, the normal distributions transform (NDT) algorithm and its application in the sonar image processing are studied. The NDT algorithm is based on probability model. The coordinate of target point is calculated instead of the gray value of image, which speeds up the calculation speed of the NDT algorithm. Several methods of image denoising and segmentation are compared to give the results and analysis of each method. Based on TI DSP chip, the NDT image matching algorithm is achieved.

Experimental Investigation and Modeling of Three-dimensional Surface Roughness in LS-WEDM of TC4

GONG Ya-dong, SUN Yao, LIU Yin

2016, 37(6):  1058-1065.  doi:10.3969/j.issn.1000-1093.2016.06.013

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Low speed wire electrical discharge machining (LS-WEDM) has an irreplaceable role in titanium alloy machining, but the complexity of microcosmic discharge makes it difficult to build the surface roughness model. Furthermore, the existing machine systems can not provide any machining parameters of titanium alloy. Box-Behnken experiment of TC4 as research object is designed by Design-Expert software. The three-dimensional contourgraph and scanning electron microscope are used to analyze the surface morphology, power spectrum and re-solidified layer, and the finished surface is isotropic and different from grinding surface. The observed result shows that the open circuit voltage is 100 V with the peak current of 40 A, and the crack extends to TC4 matrix with the pulse width of 18 μs. A quadratic model of three-dimensional surface roughness is established after model selection and significance test by using response surface method. In order to improve the prediction accuracy and generalization ability, BP neural network is applied to build a combined model. The verification experiments show that it can reduce the mean absolute error from 4.33% to 3.26% for in-sample and from 13.31% to 8.50% for out-sample, which provides a new method for electrical discharge machining simulation.

Influence of Tool Vibration Characteristics on the Hole Roundness Morphology in BTA Deep-hole Drilling

KONG Ling-fei, NIU Han, HOU Xiao-li, LIN Hong-bin, WANG Jie

2016, 37(6):  1066-1074.  doi:10.3969/j.issn.1000-1093.2016.06.014

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According to the characteristics of deep-hole drilling, a roundness morphology model of machined hole influenced by the dynamical vibration of drilling tool is established. In order to satisfy the dynamic analysis precision, the drilling tool system is discretized into multi-elements beam with the local structure characteristics by using the semi-analytical method. Two adjacent elements must satisfy the continuity condition of modal shape function transfer matrix. Based on the aforementioned method, a novel analytical model of radial cutting depth is deduced to satisfy the precise calculation and analysis of roundness morphology in the progress of practical deep-hole drilling by using Newton-Raphson iterative method, and the relationship between tool vibration properties and roundness morphology is obtained. Various numerical examples are provided to validate the feasibility of proposed method, and the relevant results can be used for the prediction and on-line control of roundness error in the process of deep-hole machining.

Research on Distribution Uniformity of Electroformed Metal Layer by Using Hollow Square Cathode-shielding Plate

LI Hui-juan, MING Ping-mei, ZHOU Tao, ZHAO Yun-long, QIN Ge

2016, 37(6):  1075-1081.  doi:10.3969/j.issn.1000-1093.2016.06.015

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A modified electroforming approach is proposed to further improve the thickness uniformity of electroformed pieces with large areas. The proposed approach involves the addition of a hollow square cathode-shielding plate to the cathode which translates circumferentially. Some simulations and experiments were carried out to study the proposed method. The research results show that both geometrical feature parameters and placement positions of hollow square cathode-shielding plate have great effects on the cathode current density distribution. The thickness distribution of deposited metal can be significantly improved using the modified process in which thickness deviation of less than 8% is achieved for 100 μm thick deposit (70 mm×70 mm). The proposed electroforming approach is expected to provide an upgraded alternative for preparing the considerably uniform large-area flat electroformed layers.

A Planning Method of Equipment Support Task Based on Priority Ordering and Particle Swarm Optimization Algorithm

PENG Peng-fei， YU Qian， LI Qi-yuan

2016, 37(6):  1082-1088.  doi:10.3969/j.issn.1000-1093.2016.06.016

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A solution space model based on task priority ordering is constructed according to the practical problem of support resource occupancy conflicts and logical relationship among support tasks in the process of equipment support task planning. A planning method of equipment support task based on priority ordering and improved particle swarm optimization is further proposed. In the proposed method, the decomposed support tasks are ordered by priority according to their importance and logical order. According to the sorted results, the task and the resource matching solution space obtained by the particle swarm optimization algorithm are adjusted for solving the problem of resource occupancy and logical sequence. A multi-dimensional asynchronous processing mechanism is proposed to ensure that the particles are feasible, so that the search efficiency of the particle swarm optimization algorithm is improved. The effectiveness and advantage of the method in the planning of equipment support tasks are verified by examples and contrastive simulation analysis. The method has broad application prospects in the field of equipment support assistant decision-making technology.

An Improved Parallel Prediction Model of Equipment Support Capability

SHUAI Yong, SONG Tai-liang, WANG Jian-ping, SHEN Hong

2016, 37(6):  1089-1095.  doi:10.3969/j.issn.1000-1093.2016.06.017

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Equipment support capability is an important constituent part of army combat power. For the sake of improving the accuracy of predicting the equipment support capability, an improved parallel prediction model is proposed for the problems existing in current prediction algorithms and their combined models. The indexes and weights of equipment support capability are confirmed by text mining. A non-isometric multi-scale interval fuzzy time series model is established by modifying the interval scale algorithm. At the same time, the particle swarm optimization algorithms about particle speed, location and inertia weight value are improved to optimize the parameters of support vector machine. An improved parallel prediction model is constructed based on the above two models, by which the weight values are calculated and the predicted weight values and the predicted values are combined to obtain the final predictive value. The given example shows that the improved prediction model is accurate.

Comparison of NLDE and DES Methods for Prediction of Cavity Aerodynamic Noise

ZHANG Qun-feng， YAN Pan-pan， LI Jun

2016, 37(6):  1096-1103.  doi:10.3969/j.issn.1000-1093.2016.06.018

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Cavity in the supersonic flow has an obvious self-sustained pressure oscillation which causes a fierce aerodynamic noise. An open cavity which length-to-depth ratio is 5.88 is simulated to predict the noise under the condition of Ma=2.0. Both detached eddy simulation (DES) method and nonlinear acoustic method for solving the non-linear disturbance equations (NLDE) method are used. The results show that NLDE method performs better in predicting the sound pressure level (SPL), and the predicted results are in agreement with the experimental results while the peak values of cavity tones obtained by DES method are 5 dB lower than those obtained by NLDE method. However, the DES method is more accurate in predicting the mode frequencies. The reason for these differences is that the DES method can capture the noise source more accurately, and NLDE method can simulate the noise propagation better. The comparison on computing resource indicates the DES method needs high resolution mesh and small time step which leads to high cost of computing resources, and the NLDE method models the fine scale turbulent motions by synthetic turbulence on coarse mesh and large time step, thus reducing the need for computing resource significantly.

Gait Analysis of an Inchworm-like Robot Climbing on Curved Surface and CPG-based Planning

JIN Ying-lian, REN Jie, FENG Wei-bo, LI Jian-jun, WANG Bin-rui

2016, 37(6):  1104-1110.  doi:10.3969/j.issn.1000-1093.2016.06.019

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The curved surface climbing gait is the key of wall-climbing robots for detecting the wind turbine blades. A mechanical model of an inchworm-like climbing robot with 5 DOF is designed, including three T type joints and two I type joints. The adaptability of the vacuum sucker and mechanical model to the arc surface is analyzed based on geometric method. The fliping gaits on curved surface are analyzed by the circular trajectory planning method. The function relationship between the joint angle and curvature radius is established based on the stable adsorption state. Based on the supervised learning method，the adaptive frequency Hopf oscillator and Kuramoto couple, a central pattern generator (CPG) module corresponding to a joint and a CPG network of robot are designed. The steady-state values of the parameters which are learned from the flat flip gait can be the initial values of the parameters of CPG network, and then the flip gait on curved surface is planned by adjusting the angle amplitudes online. The coordinated simulation of the curved surface flip gait based on Matlab and Adams is carried out，which validates the stability of the proposed CPG network. The physical prototype robot is developed, and the flip gait experiments on curved surface are carried out. The results show that the angle amplitude gained from the stable adsorbing status can be used to transfer the plane gait to curved surface gait, and the online adjustment CPG planning is valid.

Research Notes

Design and Analysis of a Novel Electric Firing Mechanism for Sniper Rifles

LIU Hua, FAN Da-peng, LI Sheng-peng, ZHOU Qing-kun

2016, 37(6):  1111-1116.  doi:10.3969/j.issn.1000-1093.2016.06.020

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A novel electric firing mechanism which is imbedded in the rifle grip is proposed for the disturbance to line-of-sight (LOS) and low action speed caused by manual firing. The structure and operating principle of the electric firing mechanism are illustrated. A parametric model is established. The electromagnet force of the electric firing mechanism is simulated in COMSOL, and the disturbance to LOS and response time of the electric firing mechanism is tested. The result shows that the mechanism is capable of electrically firing, the azimuthal disturbance of electric firing to LOS is reduced to 1/5 of manual firing, and the response time is 35 ms, which is much faster than manual firing speed. The electric firing mechanism will be helpful to catch the firing time precisely.

Research on Calibration Method of Ballistic Gelatin Based on Motion Characteristics of Spherical Projectile

LIU Fei, SHAN Yong-hai, ZHANG Jun-bin, GONG Xiao-ze

2016, 37(6):  1117-1124.  doi:10.3969/j.issn.1000-1093.2016.06.021

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In order to explore the method of using a gelatin target to assess projectile lethality, the mechanical properties of ballistic gelatin are analyzed, and the movement rule of spherical projectile in gelatin is studied based on the experimental research and the transient dynamic analysis software. The results show that the mechanical properties of ballistic gelatin should be calibrated before experiment; a cavity phenomenon may arise when the spherical projectile moves in the ballistic gelatin at a high speed, the max diameter of cavity increases with the rising of penetration depth, and the resistance and speed of projectile are reduced exponentially; and the gelatin target can be simplified as a fluid model when the projectile penetrate it at a high speed (300～1 000 m/s). The mathematical relationship between velocity and displacement is established through example analysis and calculation, and a ballistic gelatin calibration method is proposed.

Trajectory Optimization of Aerocraft Based on Shaping and Dimension Reduction

ZHANG Song, HOU Ming-shan

2016, 37(6):  1125-1130.  doi:10.3969/j.issn.1000-1093.2016.06.022

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A dimension reduction optimization strategy based on trajectory shaping is presented to improve the accuracy of trajectory optimization. The proposed method is able to improve the performance of the direct trajectory optimization method in solving non-smooth trajectory optimization problem. According to the boundary conditions, the unknown trajectory is shaped using the Bezier curves with a few shape variables. The concepts of inverse dynamic and parametric transform are introduced to reduce the original problem to a lower dimensional optimal control problem. The result shows that lower dimensional problem tends to have a better conditioning number when it is solved by direct optimization method, and the accuracy of solutions is improved dramatically. The validation of the proposed method over conventional direct optimization method is demonstrated by the simulation results.

A Terminal Multi-constraint Optimal Guidance Law for Missile

LI Qiang， LU Bao-gang， WANG Xiao-hui， WANG Yong-hai， ZHUANG Ling

2016, 37(6):  1131-1137.  doi:10.3969/j.issn.1000-1093.2016.06.023

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A new optimal guidance law is presented to satisfy the terminal constraints for the precise strike and efficient damage to ground target. The proportional-navigation constraint, impact angle and acceleration constraints are used to achieve the terminal acceleration command convergence through the guidance-order adjustment. The simulation results show that the optimal guidance law can meet the terminal constraints, and the command performance and the attack effect are improved as well.

Trajectory Research of Active High Fidelity Decoys Based on the Kinematics Modulation Principle

ZHONG Lin, RAO Bin, LI Yong-zhen

2016, 37(6):  1138-1143.  doi:10.3969/j.issn.1000-1093.2016.06.024

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For the active high fidelity decoy jamming generated by exo-atmospheric jammer, the decoys at the radar data processing level can be discriminated based on dynamics conversation law. That makes the conventional decoys invalidate to some extent. The correlative relationship among the active decoy parameters and the kinematics parameters is derived theoretically based on the moderate kinematics modulation principle. The relationship is simplified to a quadratic equation, and analytic expression is also derived. The countermeasure performances of the conventional false targets and the moderate modulated false targets are compared by computer simulation. The study illustrates that the kinematic characteristics of the active high fidelity decoys generated by the proposed method are the same as those of the true targets, achieving the purpose of mixing the false with the genuine.

Overall Optimization of Reliability and Maintainability of Major Weapon System

LYU Jian-wei, XU Yi-fan, XIE Zong-ren

2016, 37(6):  1144-1152.  doi:10.3969/j.issn.1000-1093.2016.06.025

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The availability is an important part of weapon system effectiveness, and also the prerequisite for achieving the conventional technical performance. By the discussion of the hierarchical structure of weapon system and the basic formulas for its availability, a fundamental principle of coordinating and improving the availability indicators among different subsystems is proposed based on mathematical analysis. The effect of improving difficulty of subsystem availability on improving order is discussed according to engineering practice. And an optimization method and its algorithm are designed for subsystem availability, equipment-level reliability and maintainability. Furthermore, based on a type of navy vessel, the feasibility and validity of the proposed algorithm are verified by Matlab programming. A theoretical basis and implementation approach are provided to obtain and improve the total availability with minimum cost, and take different equipment reliability and maintainability of different subsystems as an integration indicator.