Table of Content

31 March 2008, Volume 29 Issue 3

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Paper

Straight-line Running Control for Electric Drive Tracked Vehicles on Transverse Slopes

GUO Fen, SUN Feng-chun, WU Tao

2008, 29(3):  257-261.  doi:10.3969/j.issn.1000-1093.2008.03.001

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The dynamic model, the predictive model and the control model of electric drive tracked ve?hicles were derived. Based on the identification of driving intention of driver and moving states of the vehicles and comparing with traditional tracked vehicles, a new straight-line running predictive control strategy for electric drive tracked vehicles was proposed. In accordance witn transverse slope angles and variations of different roads and speeds, a straight-line running control system of vehicles was modeled and simulated by using Matlab/Simuimk. The simulation results were obtained at different conditions. The results proved the models and the predictive control strategy to be correct.

Research on Simulation Testing Device of the Ignition System for Large Caliber Propellant Charging

HAN Bo, ZHANG Xiao-zhi, XING Yu-ren,WANG Ze-shan

2008, 29(3):  262-265.  doi:10.3969/j.issn.1000-1093.2008.03.002

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A simulation testing device of the ignition system for large caliber propellant charging was designed to measure the combustion characteristics oi tne system. The tests for different ignition struc?tures were done by the simulation testing device. The optimized ignition structures were screened by the simulated results, and a series of the inner ballistic tests was carried by the two ignition structures. The results of the tests verify that the measured chamber pressure curves by the screened ignition structure are smooth and the pressure difference between the curves is attenuate. The simulation test?ing device can be used for screening the different ignition structures and guiding the ignition structure design and the safety evaluation of original firing test.

Simulation of Barrel Temperature of a Rapid-Fire Gun Based on Liquid-solid Couple

WU Yong-hai, XU Cheng, LU Chang-long, LI Feng

2008, 29(3):  266-270.  doi:10.3969/j.issn.1000-1093.2008.03.003

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The barrel liquid-cooling technology is widely used in ground-based air-defense and anti-mis?sile small-caliber automatic gun and ship-borne medium or small caliber guns. It is important to study the temperature distribution of the barrel where liquid-cooling technology is used for gun lunching safe?ty and weapon efnciency. lakmg a certain kind of rapid-fire gun as researched object, a liquid-solid u- nitized mathematic model oi heat transfer was set up by a thermal-liquid-solid coupled method coupling solid region with liquid one separated in traditional calculation method of temperature field. The tran?sient temperature oi the barrel system, whose material properties is related to temperature, was calcu?lated by CFD method, meanwhile the velocity effects of cooling water on barrel temperature were also discussed. The study result shows that the water flow cooling method for the barrel has obviously fa?vorable effect on the outer-surface cooling, along the radial direction inward, the amplitude of temper?ature decreasing caused by water flow fades out gradually; the temperature of the thin cooling-water sheet near the barrel’s outer surface changes a lot; when the flow velocity near the entrance exceeds some value, the barrel temperature field decreases just a little by increasing the flow velocity.

The Sympathetic Detonation Model Based on the Monte Carlo Theory

CHEN Hai-ping, HUANG Shun-xiang, LIU Feng, HU Fei

2008, 29(3):  271-276.  doi:10.3969/j.issn.1000-1093.2008.03.004

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According to experimental data and sympathetic detonation laws, the sympathetic detona?tion model (SDM) based on the Monte Carlo theory was established. An alveolate coordinate system wmch reflects actual distribution law of shell arrangement was proposed. The relationsnip of the expo?nent law between the logarithm of probability density function for amount of sympathetic detonation and the amount of sympathetic detonation was obtained by ^DM. The sympathetic detonation at some location, where Japanese abandoned chemical weapons (JACWs) were embedded, was simulated and analyzed by SDM, the proDability density function on amount of sympathetic detonation was obtained, ana the amount of sympathetic detonation according to the its maximum probability at a million times of detonating the embedded location was calculated. The SDM offers the basic theory for the disposal of JACWs and the simulation of the sources of risk assessment on production, transportation, storage and destruction of dangerous goods or materials.

Near-field Characteristic of Target for Radio Fuze

PAN Xi, CUI Zhan-zhong

2008, 29(3):  277-281.  doi:10.3969/j.issn.1000-1093.2008.03.005

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Taking the adaptive control of proximity or impact pattern for radio fuze as applied back-ground ,we established a near-field scattering characteristic model for the target to get the variable law of the Doppler signal and its frequency spectrum at making fuze located in electromagnetic scattering near-neid of the target under the conditions of proximity and impact patterns. Aiming at the continu?ous wave (CW) Doppler system fuze, we discussed the variable law of the Doppler signal and its fre?quency spectrum in the case of point target and further proposed the simulation results of the echo sig?nal and the Doppler frequency in the case of multipoint target. A body target scattering characteristic model was established by physical theory of optics and physical theory of diffraction, and an analytical method of the Doppler frequency spectrum characteristic was given.

CFD Grids-Based Transmission Model of the Rays Propagating Through the Hypersonic Flow Field

ZHAO Yan, WANG Tao, XU Dong, YANG Qiu-ying

2008, 29(3):  282-286.  doi:10.3969/j.issn.1000-1093.2008.03.006

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Aero-optical aberration caused by hypersonic flight can hazard the imaging quality and lower the guidance accuracy, so it is necessary to research the optical transmission through the hypersonic flow field. The density field acquired from the large eddy simulation(LES) was mapped onto the re?fractive index field in terms of the Gladstone-Dale relation, and the model that the rays transmit through the layers of the refractive index cell was built based on the CFD grids. So the geometrical op?tics was used, and a recursive ray tracing method of optical propagation through the flow of fluids was derived. Using different flow field data and different angles of incidence, the optical path difference (OPD), the optical path length and the ray coordinate excursion were calculated. The influences of al?titude, the Mach number and the angle of incidence on the optical propagation through the turbulent flow fields were discussed. This transmission model is the foundation of predicting the optical wave- front performances.

A Study of Optimal Array Distribution for Multistatic Sonar Receiver

GU Xiao-dong, QIU Zhi-ming, YUAN Zhi-yong

2008, 29(3):  287-290.  doi:10.3969/j.issn.1000-1093.2008.03.007

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The location method for passive time difference of arrival (TDOA) based on multiple sonar array was studied. Starting with the TDOA location principle, We analyzed the relation between posi?tion error and distribution geometry, and put forward the optimal distribution principle. The location precision of every array distribution was simulated to obtain optimal array distribution. The simulated result shows that tne optimal array distribution has greatly applied value in the passive location system.

Wideband Direction Finding Algorithm Based on Noiseless Covariance Matrix Transform

ZHAO Chun-hui, LIi Gang, ZHANG Chao-zhu

2008, 29(3):  291-295.  doi:10.3969/j.issn.1000-1093.2008.03.008

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Wide-band direction finding is a hot-point topic of research in array signal processing field. A novel wide-band direction finding algorithm was proposed. Noiseless covariance matrices at all fre?quency bins were transformed to noiseless covariance matrix at focusing frequency, then sub-space method was utilized to attain the DOA estimation. Compared with traditional wideband signal sub?space direction finding algorithms, the proposed algorithm does not need pre-estimate of direction of arrival. The theoretical analysis proved the estimation of the proposed algorithm to be unbiased. The simulated results proved the proposed algorithm applied to uniform linear array to De effective.

Performance of Passive Detection Based on CDMA Mobile Communication Signal

HE Zun-wen, NIU Jia-min

2008, 29(3):  296-299.  doi:10.3969/j.issn.1000-1093.2008.03.009

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CDMA mobile communication system is a synchronous one. Because oi high PN chip rate of the system’s frequency spread code, it has better performance when it is used for passive detection. The scneme in which the passive detection is conducted by the pilot signal was put forward based on analyzing the feature of CDMA mobile communication signal. The expression of the signal was de?duced, and the detection performance ol it was simulated. The result shows that the pilot signal has good detection performance both in distance and velocity, can be used for passive detection.

A New UAV Geo-location Approach Based on Common Points on Multiple Images

YU Jia-xiang, XIAO De-yun，JIANG Lu-dong

2008, 29(3):  300-304.  doi:10.3969/j.issn.1000-1093.2008.03.010

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For the accuracy of traditional UAV geo-location approach based on single image is too low to meet the needs of precise strike, new UAV geo-location method was presented. The mathematical models were constructed by linearization of the collinearity equations to iteratively compute the pose angles and focal length of the camera. The camera pose angles and the focal lengths were precisely reckoned by the three images of the target and at least three identifiable common point coordinates a- mong the images. /I hree-dimension coordinates of the ground target were calculated using forward in?tersection. The new method, which is independent of DEM and the measured values of camera pose angles, eliminates the two of the three primary error sources in the traditional UAV target location method and has better location precision. The. results of simulation and real image experiment show that the accuracy of the UAV position is main effective factor on that of the estimated target location, when the former is 5 m, the latter is about 10 m which is much less than that of the traditional.

Analysis and Design of Multi-beam Millimeter-wave Parabolic Reflector Antenna

LI Cheng-guo, MU Shan-xiang, ZHANG Zhong-chuan

2008, 29(3):  305-307.  doi:10.3969/j.issn.1000-1093.2008.03.011

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Aiming at engineering application, we analyzed radiation of multi-beam parabolic reflector antenna with conical horn feed source. On the basis that the radiation integral was evaluated rapidly via the FHT, the key parameter and radiation pattern of parabolic reflector antenna were derived through simulation and optimization, so as to simplify the design and the computation of parameters in engi?neering. A millimeter-wave parabolic reflector antenna of eight beams was designed by the optimized results. This study is instructive to engineering design of multi-beam parabolic reflector antenna.

A Method of Global Motion Estimation of Infrared Imaging Based on RANSAC + LS Algorithm

ZHUO Zhi-min, YANG Xin-yuan, YANG Lei

2008, 29(3):  308-312.  doi:10.3969/j.issn.1000-1093.2008.03.012

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A method of global motion estimation of infrarea imaging based on RANSAC + LS algorithm was proposed. The realized processes of the method are as follows： the matching are previewed; the global motion parameters are estimated by the algorithm for inliers as many as possible; the motion compensation of the parameter estimation results, are carried out by a bilinearity interpolation method. The method has high efficiency, uses inliers as many as possible compared with RANSAC algorithm, and can overcome LS algorithm’s defect which is susceptiole to error matching and outlier. The exper?imental results with taken practically infrared imaging show that the calculation accuracy of the algo?rithm is higher than that of RANSAC and LS algorithms.

Analysis on Operating Range of a Staring Infrared Search and Track System for Armed Helicopter

MU Da, WANG Jian-li，CHEN Tao

2008, 29(3):  313-317.  doi:10.3969/j.issn.1000-1093.2008.03.013

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Operating range is the main technique index of an infrared search and track (IRST) system. As the different strategic targets have different infrared radiation characteristics, the different operat?ing range models for the different targets should be established. Through analyzing the radiate charac?teristic of the armed helicopter in theories, the operating range model of a staring IRST system for the armed helicopter was established. The influence factors in every aspect on operating range were ex?plored by the calculated result of a living example to provide the theoretical basis for the design and ap?plications as well as the comprehensive evaluation of an IRST system.

Weak Line Spectrum Detection Based on Sign Function Type Stochastic Resonance in Non-Gaussian Marine Noise

DONG Hua-yu, ZHANG Xiaobing, XUAN Zhaolin

2008, 29(3):  318-322.  doi:10.3969/j.issn.1000-1093.2008.03.014

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Taking sign function as a stochastic resonance (SR) moael, we researched a signal detection method in the non-Gaussian underwater noise environment and analyzed tlie performance of the detec?tor. In contrast with SR based on Langevin function, the proposed model have a higher local signal-to- noise ratio gain and can be used in a wider frequency range. Numerical simulation indicates that, the more evident the non-Gaussian characteristics of noise are, the more excellent the performance of the detection method based on sign function SR is. The real data certify the proposed SR’s validity.

Modeling and Analysis of Guidance Loop with Velocity Pursuit Guidance Law

SONG Jin-wu，XIA Qun-li，XU Jin-xiang

2008, 29(3):  323-326.  doi:10.3969/j.issn.1000-1093.2008.03.015

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Taking initial aiming error as inertial small perturbance, we established a model of guidance loop with velocity pursuit guidance law at the ideal conditions and deduced an analytical expression. Normalizing the analytical expression, we obtained only one design parameter, non-dimentional termi?nal guided time, which can directly determine the guidance accuracy and the missile lateral accelera?tion. The scope of the parameter was given by analyzing non- dimensional lateral acceleration and miss- distance.

Strength Analysis and Wave Permeance Property Test of Electromagnetic Window Lid Made from Resion Base Composite

ZHANG Jun, HE Yue-jin, ZHAO Cheng,ZHANG Heng

2008, 29(3):  327-330.  doi:10.3969/j.issn.1000-1093.2008.03.016

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The materials and the structure of electromagnetic window lid were designed based on the requirements of wave permeance property. The designed lid was analyzed in strength by FEM and the manufactured one was tested in compressive strength. The result of strength analysis is consistent with that of compressive strength test, and meets the requirements of the lid strength. The wave perme- nance property test of electromagnetic window lid was also carried out. The delected result shows that the average attenuations of the penetrant signals in two frequency channel through the lid are 1.30b dB and 1.588 dB, respectively, and the corresponding wave permeance rates are 86% and 83 %, respec?tively ;the selected material can meet the requirements of wave permeance property.

Research on the Motion of Three-dimensional Underwater Explosion Bubble with Dytran Software

RONG Ji-li，LI Jian

2008, 29(3):  331-336.  doi:10.3969/j.issn.1000-1093.2008.03.017

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The underwater explosion bubble motion under the gravitation was simulated and analyzed using MSC. DYTRAN finite element analysis software. The bubble impulse process was numerically calculated by the introduced technique of processing flow field boundary at different TNT charges with same depth and different depths with same TNT charge. The radial displacement histories of the bub?ble were acquired by analyzing and sumarizing the radius and the impulse period of the bubble at the above operating conditions. The computational results of the radius and the impulse period were com- parea with the experimental results ? The compared results show that the former is consistent with the latter, the finite element model is correct and effective. The research has value to correlative theory re?search and engineering calculation.

Investigation of Integrated Muiti-disciplinary and Multi-objective Optimization of the Torpedo Shape Design Method

YU De-hai, SONG Bao-wei, YANG Shi-xing, LI Jia-wang, LIU Xu-Iin

2008, 29(3):  337-340.  doi:10.3969/j.issn.1000-1093.2008.03.018

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A multi-disciplinary and multi-objective optimization of the torpedo shape design method was proposed. The design model for integrated multi-disciplinary and multi-objective optimization of the torpedo shape was built. The frame of improved concurrent subspace optimization algorithm was pro- Dosed. An example of the torpedo shape optimization design was given. The optimized results were compared with the original shape. The compared results show that the optimized performances in the respects of hydrodynamics and acoustics are greatly improved, and the proposed method is feasible and adaptable.

Applying an Improved Extremum Seeking Algorithm Based on ARNN to Calculating the Equilibrium States of a Class of Saucer-like Air Vehicles

HU Yun-an, ZUO Bin, LI Jing

2008, 29(3):  341-347.  doi:10.3969/j.issn.1000-1093.2008.03.019

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To solve the drawbacks of slow convergence and large random existing in some trimmed- methods, such as simplex algorithm and mixture genetic algorithm, the characteristics of equilibrium states in the steady flight of saucer-like air vehicles were studied, and an improved extremum seeking algorithm based on annealing recurrent neural network (ARNN) was proposed to complete the calcula?tion of equilibrium states of saucer-like air vehicles. The calculation of trimming values in the steady f lignt was transformed into solving the cost function (CF) introduced in the paper, and the trimming values in some conventional steady states of saucer-like air vehicles were solved by the proposed algo?rithm .The simulated results verify that the algorithm proposed has better convergence, Steadiness and precision than that of the mixture genetic algorithm in the same background.

Technical RISK Analysis of Ship-borne Multiple Function Rocket Launcher Based on Gray Cluster Decision

WANGFeng，MA Da-wei, WU Xiaoyun, et al

2008, 29(3):  348-351.  doi:10.3969/j.issn.1000-1093.2008.03.020

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The development of ship-borne multiple function rocket launcher is a complicated system en?gineering .As it is difficult to quantitate evaluating index and attributive value, the analysis and evalu?ation of technical risk become the bottle-neck in the risk management of weapon development program. Aiming at grey property of technical risk, we proposed an integrative evaluation method of grey clus?tering evaluation combined with analytic hierarchy process (AHP) for technical risk of weapon devel-opment. Technical risk analysis for three overall schemes of ship-borne multiple function rocket launcher was taken as an example, risk grades of every subsystem were analyzed first, then technical risks of three overall schemes were sorted. fhe evaluating result would provide some decision support for the choosing of overall schemes of the weapon system.

A Fault Diagnosis Approach of the Large complex System Based on Bayes Theory

LIAN Ke, LONG Bing, WANG Hou-jun

2008, 29(3):  352-356.  doi:10.3969/j.issn.1000-1093.2008.03.021

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According to the characteristic of the large complex system, we Duilt a fault diagnosis model in fault space to describe the relationship between fault sources and test set. Based on it, Bayes theory was introduced into the problem of fault diagnosis of the large system. The running states of the sys?tem were estimated according to the maximal posterior probability. We concluded the problem as a set cover problem (SCP)，and the near-optimal resolution was given by Lagrange relax algorithm. The example in which the algorithm is applied to the fault diagnosis of the Apollo prelaunch data guoted from Ref. Lll] demonstrates the algorithm has enough precision and efficiency.

Research Notes

Preparation and IR Spectrum Characteristics of Nano-material ZnO Doped with NiO

TANG Ji-long, LIU Guojun, FU Xiu-hua, WEI Zhi-peng,WANG Jing

2008, 29(3):  357-360.  doi:10.3969/j.issn.1000-1093.2008.03.022

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In order to seek a new electromagnetic wave absorbing material for aircraft stealth, aiming at IR spectrum characteristics of ZnO, the nano-material ZnO doped with NiU was prepared by a com?bustion method. It was determined that the sample is composed of orthorhombic hexahedron NiO and hexagonal crystal ZnO by the D/max-ra type X-ray diffractometer, the Zn position is replaced by Ni partially to form effective doping; the particle sizes of the sample are about 30 nm by the JEM 1000 EX2 transmission electron microscope; a wide absorption band of the sample from 6.89 μm to 16.7 μm exists in medium-far IR band by the UV-3100 PC spectrophotometer and FTS 3000 (Bio-Rad) IR spectrometer, which covers the medium-far IR band from 8 μm to 14 μm of military radar.

Deformation Characteristic of Tungsten SKeleton/ Zr-based Amorphous Alloy Composites Under High-speed Impact

CHENG Huan-wu，WANG Lu, XUE Yun-fei，WANGHai-Ii, WU Qing-shan，ZHANG Hai-feng，WANG Ai-min

2008, 29(3):  361-363.  doi:10.3969/j.issn.1000-1093.2008.03.023

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The deformation characteristic of the tungsten skeleton/Zr-based amorphous alloy composite under high-speed impact at room temperature was investigated by self-made high-speed impact tester. It is found that the deformation characteristics of the composite mainly contain the tungsten skeleton fracture, softening of the amorphous alloy and flowing along the deformation direction of tungsten skeleton. An obviously common boundary between different deformation bands appears on the shear section, which farms the shear bands and the cracks.

Design and Implementation of Undulatory Bionics Propeller Based on Single Flexible Fin

LIN Long-xin, SHEN Lin-cheng, XIE Hai-bin

2008, 29(3):  364-368.  doi:10.3969/j.issn.1000-1093.2008.03.024

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The undulatory bionlic propeller is a new underwater propeller which imitates the undulatory dorsal fin of Uymnarchus Niloticus. The goal and the general idea of this system were put forward. The sub-systems composed of flexible fin, mechanism, control system, actuator were designed in de?tail. The tests of reliability and sealing property, the electric debug, and the pool experiment were car?ried out, as well as some experimental results were given. The investigated results indicate that the mechanism and the sealing property meet demands of the design; the control and sense systems are sta?ble and reliable; the related conclusions of undulatory propellant theory of the flexible fin are valid.

Robustness Analysis of Terminal Area Energy Management Trajectory for Reusable Launch Vehicle

SUN Chun-zhen, HUANG Yi-min

2008, 29(3):  369-373.  doi:10.3969/j.issn.1000-1093.2008.03.025

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In order to research the robustness of terminal area energy management(TAEM) trajectory for reusable launch vehicle(RLV), a method of trajectory robustness assessing based on nonlinear e- quations of motion was developed. A trajectory design method basing on the nonlinear equations of mo?tion was introduced. According to the principle of the method, the concept of TAEM trajectory ro-bustness was defined, and uncertainties of the influence on TAEM trajectory robustness were listed. The energy gradient was defined as the measure of the ability to increase and decrease energy to remove energy dispersions, and the primary factors affecting the energy gradient were listed. The method of trajectory robustness analysis for TAEM was developed. Taking a certain RLV demonstrator for ex?ample, the influences of the model uncertainties on the energy corridor and the nominal trajectory ro?bustness were analyzed.

Adaptive Integral Backstepping Surge Motion Tracking Control for an Underwater Vehicle

GAO Jian, ZHAO Ning-ning，XU De-min, YAN Wei-sheng

2008, 29(3):  374-378.  doi:10.3969/j.issn.1000-1093.2008.03.026

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The nonlinear tracking and controlling problem of surge motion for underwater vehicle was proposed. Taking aim at generally existential uncertainty factors, such as unknown ocean current, un?known parameters in dynamic model and external constant disturbance, a novel adaptive nonlinear con?troller with integrator based on backstepping was designed by using adaptive mechanism to overcome the uncertain factors and adding integral item in feedback to improve the robust against the unmodeled dynamic character. The designed controller can make underwater vehicle track the instruction of the reference position globally and asymptotically. The functions of adaptive mechanism and integral item were analyzed by simulation method at different conditions. The simulated results show that the track?ing system of closed loop has global and asymptotical stability.

A Convex Partition Algorithm for a Polygon with Holes

JIAO Li-nan，TANG Zhen-min

2008, 29(3):  379-384.  doi:10.3969/j.issn.1000-1093.2008.03.027

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The algorithm makes convex partition of a polygon with holes using monotone chains, it in?cludes three stages： the first one decomposes a polygon with holes into ordered monotone chains; the second one divides the original polygon with holes into monotone polygons through combinations and splits of ordered monotone chains; the third one partitions every monotone polygon into convex poly?gons. Proofs and complexity analysis of all stages in the algorithm were given. The experiment and analysis show that the average complexity of the algorithm approximates O(nlgn).