Table of Content

28 February 2007, Volume 28 Issue 2

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Paper

Research on Driving Performances of Electric Transmission Tracked Vehicles Based on Torque Control Strategy

SUN Feng-chun, CHEN Shu-yong, GUO Fen

2007, 28(2):  129-133.  doi:10.3969/j.issn.1000-1093.2007.02.001

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The feasibility study on controlling the movement of an electric transmission tracked vemcie through controlling the output torques of left and right side motors directly was discussed in principle. The torque control strategy was put forward. The 3-D multi-body dynamics virtual prototype model of tracked vehicle running gear and the models oi integrated controller and motor control systems were built based on multi-body dynamics analysis software RecurDyn/ Track-HM and control system analysis software Matlab/Simulink. Also, the collaborative simulation model based on interface technology of different softwares was built. Under the conditions of the acceleration time (0?32 km/h), straight- line offset data in 100 m at different velocities, B/2 steering and climb ability of 15°slope, the vehi-cle's ariving performances were researched by collaborative simulation and reality vehicle test. The correctness of the model and torque control strategy is validated by analysis and comparison, which lays the foundation for further research on other driving performances.

A Research on Fault Diagnosis of Working Position Gear in Tank Gear-box

FAN Xin-hai, QIU Mian-hao, WANG Zi-ying,AN Gang

2007, 28(2):  134-137.  doi:10.3969/j.issn.1000-1093.2007.02.002

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A fault diagnosis method of working position gear in tank gear-box was put forward based on simulating the fault of working position gear in actual tank gear-box, extracting the envelope of vibra-tion signal by Hilbert transformation amplitude demodulation, and zooming low frequency band to the envelope signal.

Fatigue Life Simulation of Key Components of Running Gear for a Self-propelled Gun

YI Dang-xiang, LIU Chun-he, Lü Guo-zhi, LI Xin-jun

2007, 28(2):  138-143.  doi:10.3969/j.issn.1000-1093.2007.02.003

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The virtual prototype of the self-propelled gun was established, the load of the key compo-nents of running system under various driving conditions was simulated and obtained. For a single con-dition, stochastic load acting on the torsion bar was simulated, counted, evaluated and tested to obtain a distribution form. Using the weight coefficient method, the probability density deducing method and the steepest descent method, the fatigue load on various conditions was synthesized and extended. Moreover, two-dimensional design spectrum of the whole lives was established. The fatigue parameters of the torsion bar ’ s material were modified with modified miner (MM) rule and elemental miner (EM) rule. Utilizing the nominal stress method, the torsion bar’s fatigue safe lives were predicted. As a result, it is not probable to propagate fatigue cracks for the torsion bar within 12 814 km. And it shows that MM is more reasonable than EM.

Design of a Machine Gun Mount with Buffer-type Spade

WANG Rui-lin, LI Yong-jian, ZHANG Jun-nuo

2007, 28(2):  144-147.  doi:10.3969/j.issn.1000-1093.2007.02.004

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Machine gun mount is a base to ensure the iinng stability of the weapon. The machine gun’s stability was analyzed and a mount spade with buffer action was designed. By simulating calculation, the results show that the vibration of muzzle at y9 z directions can be reduced effectively by using the structure, which is helpful to improving the iinng precision of machine gun. The method can be used for solving the contradiction between reducing machine gun’s mass and improving firing accuracy of macmne gun.

Evaluation Method of Fighting Effectiveness of Small Arms System Based on Shooting Efficiency

GUO Kai, XU Cheng

2007, 28(2):  148-152.  doi:10.3969/j.issn.1000-1093.2007.02.005

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Aimed at the characteristics oi three battle situations, namely one to one, one to many, and many to one, the evaluation method of fighting effectiveness for small arms system based on their shooting efficiency was set up, where the seven different conditions of the head, head-chest, half-body, face-running, side-running, whole body and scattergun-body for the enemy personnel were sep-arately considered, and mathematic models of hit and damage probabilities established. Three different small arms systems were chosen and applied in the simulation to qualify the method. The hit and dam-age probabilities were analyzed at fighting processes for different small arms systems.

Discussion About Mechanism of Breech-Blow Caused by Gun Propellant Charge

YUN Lai-feng, RUI Xiao ting, WANG Hao, QIU Cong-Ii，CHEN Tao

2007, 28(2):  153-157.  doi:10.3969/j.issn.1000-1093.2007.02.006

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From the view point of the fracture of propellant charge causing problems of launch safety, it is pointed out that the safety procedure of pressure wave is inadequate to assess the launch safety of gun propellant charge, which is based on the initial negative differential pressure and sensitivity tests, ana tne operation oi the procedure is inconvenient. Generally, there does not exist a correspondence re-lationship between the degree of pressure wave and maximum chamber pressure. The degree of pres-sure wave cannot describe the degree of fracture of propellant charge in the chamber, and cannot depict the environment of the fracturing propellant charge exactly and wholly. The criteria of identification for launch safety of gun propellant charge should be built up on the basis of depicting the degree of pro-pellant fracture.

The Catalytic Action of Combustion Catalysts in Solid Propellant with Uniform Design and Regression Analysis

GAO Hong-xu, ZHAO Feng-qi, LI Shang-wen

2007, 28(2):  158-162.  doi:10.3969/j.issn.1000-1093.2007.02.007

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In order to observe the effect of combustion catalysts on burning rate of solid propellant, the catalytic action of composite catalysts in the combustion of solid propellant was studied by uniform de-sign and regression analysis of mathematical model. The results indicate that lead salt and carbon black affect the burning rate of solid propellant more greatly than copper salt. At the same time, there are interactions among lead salt, copper salt and carbon black. Their actions appear as the different ex-pression forms with the change of pressure in the pressure range selected. By means of uniform design experimentation, the preferable combination among the contents of lead salt, copper salt and carbon Diack was obtained for the combustion performance of solid propellant.

Real-time Window Enhancement Method for Image of Uncooled Thermal Sight

WANG Shi-yun，CHANG Ben-kang, ZHANG Jun-ju, QIAN Yun-sheng,SUN Lian-jun,YU Chun-yu

2007, 28(2):  163-166.  doi:10.3969/j.issn.1000-1093.2007.02.008

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To realize the real-time problem of the image enhancement technology in the infrared ther-mal sight system, a window enhancement method was put forward according to the vision characteris-tic of human’s eye. A proper size sub-image was first taken out of the whole infrared image and the sub-image was then processed with a certain enhancement algorithm, while pixels out of the sub-image were not processed. The hardware processing flow chart was given. It is proved from the analysis that the processing time of background pixels is saved with the window enhancement method and real-time responsibility of image processing is improved. Moreover, this method does not damage the enhance-ment effect and it is especially useful m the scene with small object.

A New Structure for Vertical，Cavity Surface Emitting Laser

HAO Yong-qin, LIU Wen-li, ZHONG Jing-chang, ZHANG Yong-ming, FENG Yuan, ZHAO Ying-jie

2007, 28(2):  167-169.  doi:10.3969/j.issn.1000-1093.2007.02.009

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A new mesa structure with ring-distributed perforations was presented, and vertical-cavity surface emitting Iaser(VCSEL) with such structure was fabricated. The testing results snow that these VCSELs operate with good performance, light output power is 1.34 times as much as that with ring groove?

An Optoelectronic Inspection Method for the Taper of a Bore

ZHANG Guoyu, ZHANG Ya-ting, XU Xi-ping, ZHANG Lian-cun

2007, 28(2):  170-174.  doi:10.3969/j.issn.1000-1093.2007.02.010

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Based on laser optical triangulation displacement inspecting technology and grating displace-ment inspecting technology, an optoelectronic non-contact measuring method and a laser-scanned opto-electronic measuring system were presented for measuring the taper of the Φ30 mm bore. In this paper, the constitution and overall structure of the system are described. The taper measuring method and the principle are discussed and theoretically analyzed, the non-contact measuring method for inner diameter is emphatically expounded by the principle of laser optical triangulation. Moreover, the measuring ac-curacy of the system was verified by experiment. I ne results indicate that the measuring accuracy of inspecting system is superior to ± 0 ? 003 mm, and the inspecting repetition accuracy is superior to 土 0.002 mm. It indicates that the system can fulfill the inspecting accuracy demand for inspecting the taper of the small-caliber bore, and the inspecting method is applicable.

Digital Image Stabilization Using Kalman Filtering

XING Hui, YAN Jing-long, ZHANG Shu-jiang

2007, 28(2):  175-177.  doi:10.3969/j.issn.1000-1093.2007.02.011

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A real-time stabilization system using Kaiman filtering for video reconnaissance was present-ed. Inter-frame global motion vectors were predicted by feature matching based motion estimation. The global camera motion was defined in terms of constant velocity motion models, and Kalman filter-ing was employed to facilitate smooth operation. Experimental results for many video sequences show that the method can eliminate high frequency tremble, remain active motion of camera and realize real time image stabilization satisfactorily.

A New Electric-mechanical Coupled Study on Superlattice Structure in Semiconductors

ZHANG Bin-zhen, LI Ke-jie, ZHANG Wen-dong, XUE Chen-yang

2007, 28(2):  178-181.  doi:10.3969/j.issn.1000-1093.2007.02.012

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Double potential barrier superlattice quantum membrane made from AlAs/ GaAs has been grown through molecular beam epitaxy technology on (001)-oriented GaAs substrates. Pressure-de-pendent current-voltage characteristics of superlattice nlm were studied in room temperature. Mea-sured results show that the drift of I- V curve is proportional to the applied force. It provides a basis of research for electric-mechanical coupled transducer based on resonant tunneling effect.

The Research on Electromagnetic Scattering Property of Finite Dipole Antenna Array

LIAO Yan-ping, YANG Shen-yuan, MA Hui-zhu,HOU Yan-Ii

2007, 28(2):  182-186.  doi:10.3969/j.issn.1000-1093.2007.02.013

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A new method solving electromagnetic scattering property of finite dipole array was pro-posed .Because the surface current distribution for each Rao-Wilton-Glisson ( RWG) edge element was replaced by an infinitesimal dipole in the dipole model, the scattering field was then obtained from the contributions oi infinitesimal dipole. Finally, the scattering simulated patterns were given from differ-ent array element separations, incident frequencies, incident angles and array element numbers with po-lar coordinates. It provides the basis for the research on other kinds of array antennas’ scattering prop-erties .

Bearing Estimation of the Separate Sections of a Volume Target with Non-Typical Vector Acoustic Intensity Array

CHEN Shao-hua, XIANG Jing-lin, LUO Jian,HAN Peng

2007, 28(2):  187-191.  doi:10.3969/j.issn.1000-1093.2007.02.014

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Ships at short distance should De considered as a volume target. A scheme was proposed for the bearing estimation of the separate sections of a volume target with a non-typical vector acoustic in-tensity array. The bearings of the midway section and the section between the midway and the stern of the volume target radiating low frequency noise were estimated with the vector acoustic intensity method, while the bearing of the stern section radiating high frequency noise was estimated with the hign precision adaptive FIR time delay estimation method, and both the above two methods used the same array of small size. To test this scheme, experiment was conducted in a semi-anechoic chamber, with 3 loudspeakers simulating the sound sources of the 3 separate sections of the volume target. Ex-perimental results show that bearings of the 3 sections can be estimated with satisfying precision and the 3 sections are distinguishable. This scheme provides a feasible approach for the bearing estimation of the 3 sections of a ship with a small array.

An Algorithm for Passive Direction Estimation to Low Altitude Target Based on Particle Velocity Measurement

CAI Zong-yi, ZHAO Jun-wei, LI Jia-wu, GUO Yan，XU Xue-zhong，TANG Yu-zhi, DONG Yong-feng

2007, 28(2):  192-196.  doi:10.3969/j.issn.1000-1093.2007.02.015

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Passive acoustic direction finding is an important aspect in the acoustic surveillance. In order to detect the low altitude targets, the method for passive bearing estimation with acoustic vector sen-sors was presented. Based on the technique of measuring the field particle velocity, the algorithm of passive bearing estimation to low altitude target was derived. Simulating with the noise signal radiated from the real target, the results show that the algorithm can achieve direction estimation in precision of 2° when the size of acoustic vector sensor is 0.3 m and signal-noise-ratio (SNR) = 0 dB. The experi-ment on particle velocity directivity of the acoustic vector sensors was also carried out, and gained the figures of the particle velocity directivity of the vector sensor. It has the fine spatial directivity. The experiment results also show that the method can reach a high precision, and can be used in passive acoustic direction estimation to low altitude target. Furthermore, the results of the research could be directly used in estimating the direction of the targets such as helicopters, missiles, and so on.

Grindability Evaluation of Ceramics via Grey Clustering Approach

YU Ai-bing, WANG Min, TIAN Xin-li

2007, 28(2):  197-201.  doi:10.3969/j.issn.1000-1093.2007.02.016

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A comprehensive evaluation method for ceramic grindability was proposed. More influencing factors of ceramic grindability can be considered simultaneously. Ceramics to be evaluated were selected as clustering objects, influencing factors of ceramic grindability were selected as clustering items. Grindabilities of ceramics were classified as different grey degrees, u-rey whitenization functions of in-fluencing factors for ceramic grindability were determined. Fixed weight clustering coefficients were calculated with deviation matrix method.しlustering vectors for ceramics were calculated. finally, grindabilities of ceramics were classified according to comparison of clustering coefficients. Silicon car-bide, alumina, zirconia and silicon nitride were evaluated as the examples. The property parameters and machining process/output parameters were considered together. Four ceramics were classified as three grindability grades. I He research results show that grey fixed weight clustering approach is a reasonable method for grindability evaluation of ceramics.

Hydrodynamic Pressure Modeling and Verification of Contact Zone on Abrasive Jet Finishing with Grinding Wheel as Restraint

LI Chang-he, CAI Guang-qi, XIU Shi-chao, LIU Feng

2007, 28(2):  202-205.  doi:10.3969/j.issn.1000-1093.2007.02.017

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The three-dimensional hydrodynamic pressure model of wedge-like zone between wheel and workpiece on abrasive jet finishing with wheel as restraint was established based on Navier-Stokes and continuity equations. The simulation results of three-dimensional hydrodynamic pressure show that the hydrodynamic pressure is directly proportional to grinding wheel velocity and inversely proportional to minimum clearance between wheel and workpiece, and the peak pressure is generated just in the mini-mum clearance region in whicn the higher pressure gradient occurs. It can also be concluded that the pressure distribution is uniform in the direction of width of wheel except at the edge of wheel in which side-leakage exists. The smaller the gap distance is, the narrower the peak pressure distributions be-come. The hydrodynamic pressure at weSge-like zone between wheel and workpiece was investigated experimentally. The experimental results show that the theoretical model is in agreement with experi-mental results and the model can well forecast hydrodynamic pressure distribution at contact zone be-tween wheel and workpiece.

Experimental Techniques and Analysis

A Measuring System of Inertia Moment of Missile and Its Error Analysis

LI Hui-peng, TANG Wen-yan, ZHANG Chun-fu, SUN He-yi, WANG Jun

2007, 28(2):  206-208.  doi:10.3969/j.issn.1000-1093.2007.02.018

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A large system used for measuring inertia moment of missile with the mass ranged from 100 kg to I 200 kg was developed. The measurement of missile’s inertia moment relative to three axes was realized by an expandable measuring arm under only one-step installation having less the position-ing errors than multi-step installations. The main factors affecting precision were also analyzed quanti-tatively. The inertia moment of standard body was measured, and the results show that the error is less than 0.1% in measuring inertia moment relative to every axis.

Comprehensive Reviews

Review Research Advancement on Graded Ceramic- Metal Armor Composites

WANG Yang-wei, WANG Fu-chi, YU Xiao-dong, MA Zhuang

2007, 28(2):  209-214.  doi:10.3969/j.issn.1000-1093.2007.02.019

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The preparation process, dynamic response under shock load, material design, ballistic test and modeling of the graded ceramic-metal armor composite were reviewed. The advantages of the graded armor composite were discussed m detail, and furthermore the emphasis of future work was pointed out.

Short Papers

Optimal Design for Shaped Charge Structure Based on an Experimental Design Method

YANG Dong-mei, ZHANG Ai-ping, ZHAO You-shou

2007, 28(2):  215-219.  doi:10.3969/j.issn.1000-1093.2007.02.020

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A shaped charge structure is usually designed by experience, based on lots of tests and simu-lation calculations, and the final decision is usually chosen from several candidates. It is not a real opti-mum design, and the design period is long. An optimization method for shaped charge structure design based on experimental design method was proposed. Without forming the objective function, con-straint functions and differential calculations, the optimization method is simple and feasible. A set of combinations of design variables such as liner angle, wall thickness and so on, with their three level values was arranged in a propriety orthogonal array in order to evaluate the structural response, namely the jet penetration depth of the shaped charge. The optimum solution of all design variables with the optimum jet penetration depth was attained by iterative calculations on the basis of analysis of variance and F-test application. The structural design of 12D mm caliber shaped charge as an example was calcu-lated ana analyzed with the proposed optimum program. By comparing the results of program calcula-tion and the former scheme, the optimization method based on experimental design method indicates feasibility in helping to get an optimum scheme of the shaped charge structural design.

Design of Self-spin Frequency for Rotating Missiles

ZOU Ru-ping, ZHANG Yan-feng

2007, 28(2):  220-222.  doi:10.3969/j.issn.1000-1093.2007.02.021

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Aimed at the design of rotating missile’s self-spin frequency, the factors of influence and principle for the choice of self-spin frequency were presented m consideration of the missile ’ s dynamic stable region. Taking a type of missile as an example, the self-spin frequency of the rotating missile was designed by calculating power factor, intrinsic frequency and dynamic stable region of the missile and analyzing systematic frequency. The method presented in this paper has reference value for self-spin frequency design in the similar kinds of missiles.

Research on Developmental and Productive Cost for Aircraft Based on Grey Correlation Analysis Theory and Equalisation-Engineering-Value-Rate Method

XIE Jian-xi, SONG Bi-feng, LIU Dong-xia, XU Jian, YAO Qin

2007, 28(2):  223-227.  doi:10.3969/j.issn.1000-1093.2007.02.022

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Based on the large amount of historical data at home and abroad, by using grey correlation analysis theory, the determination method of cost drive factor on developmental and productive cost for aircraft, which overcomes the shortcoming of scarce sample data, was established. Combining the fea-tures of less known knowledge in early conceptual design stage for aircraft, the authors proposed the definition of equalisation-engineering- value-rate. A developmental and productive cost estimation model fitted for new aircraft at home was presented by applying the above method to modify the existent model established by foreign countries. The model provides a new thought for the research on develop- menal and productive cost in aircraft top-level design and cost-effectiveness assessment.

Modeling and Decision- Making of Multi-target Optimization Assignment for Aerial Defense Weapon

WANG Xiaoyi, LIU Zai-wen, HOU Chao-zhen, YUAN Ju-mei

2007, 28(2):  228-231.  doi:10.3969/j.issn.1000-1093.2007.02.023

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On the basis of analyzing the mechanism of decision-making, a multi-target assignment deci-sion-making model used to research aerial defense weapon system was set up to realize the multi-target optimization assignment of missiles. An improved particle swarm optimization (PSO) based on the model was put forward to compute optimization assignment for aerial defense weapon. Comparing with genetic algorithm (GA), the results of two examples prove the method to be effective and superior.

Research Notes

The Theoretical Study of the Molecular Structure of TATFIW

LI Li-jie, CHEN Shu-sen, CHEN Hua-xiong, JIN Shao-hua, ZHAO Xin-qi

2007, 28(2):  232-236.  doi:10.3969/j.issn.1000-1093.2007.02.024

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The molecular structure of triacetyltriformylhexaazaisowurtzitane (TATFIW) was opti-mized and its IR harmonic frequency was calculated by ぃaussian 98 software package at the level of B3LYP/6-3lG. It was found that molecular inner hydrogen bond exists in TATFIW, acetyl is easier off than formyl in the nitrolysis with nitric-sulfuric mixed acid, by analyzing bond length, bond angle, dihedral angle and charge of TATFIW theoretically. Above mentioned result agrees well with that of the experiment. The comparison of IR harmonic frequency and intensity between calculated and exper-imental values, the relative error of IR harmonic frequenceies which is less than 3.6%, were given.

Stepped Frequency Pulse Radio Fuze

HU Xiu-juan, DENG Jia-hao, SANG Hui-ping

2007, 28(2):  237-241.  doi:10.3969/j.issn.1000-1093.2007.02.025

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Based on the case of air-to-ground missile, a Dasic geometrical relationship of missile-target encounter was given and the basic simulation model was established including transmitting, receiving and signal processing. The influences of Doppler effect on radio fuze performance in different cases of missile-target encounter and velocity compensation were analyzed. Rational design of pulse waveform permits the realization of high explosive range and precise attacking.

Multi-objective Optimization Design of the Multilayered Planar Shield

GAN Ming-gang, CHEN Jie, CAI Tao, PAN Feng

2007, 28(2):  242-245.  doi:10.3969/j.issn.1000-1093.2007.02.026

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The shielding effectiveness of multilayered planar shield is the strong non-linear function of incident angle，conductivity, magnetic permeability, the dielectric constant and the thickness of every layer. Design of the multilayered composite materials is to solve the equations made of these functions. It’s very difficult to solve the problem by numeric methods. The multi-objective optimization model was presented to solve the problem of the electromagnetic design. The total weight，cost ana thickness are the optimization objects and the shielding effectivenesses (SE) in some frequencies are the con-strained conditions in the model. And the genetic algorithm was used to design the multilayered com-posite material by the existent multilayered planar composite electromagnetic shielding material model. By making use of this method, the different shielding materials and the corresponding tmckness of ev-ery layer can be designed for given shielding effectiveness (SE) in some frequencies, different incident angles. Finally the method was simulated, the results demonstrate the validity of the method.

A Measurement and Controlling System of Ground Hot-firing Test for Rocket Roll-control Engine

REN Yong-feng, LIU Wen-yi, ZHANG Wen-dong

2007, 28(2):  246-248.  doi:10.3969/j.issn.1000-1093.2007.02.027

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A measurement and controlling system for hot-firmg test based on PXI-bus was proposed. Besides I/O module of PXI-bus, it adopts auxiliary control logic circuit, which can decompose real time control process into two parts ： process arranging part which is completed by PXI，and executing part which is completed by auxiliary control logic circuit. Theoretical precision of response time for real time* control can be 5 μs, while executing precision of the control system can be 0.1 ms in practice. So, the method mentioned above could make up for the limitation of real time control when using PXI-bus, and also advance real-time management ability of computer system when facing different missions at one time.

A New Method of Load Separation from Autonomous Underwater Vehicle

SONG Baowei, SHAO Cheng, LI Jia-wang,DU Xiao-xu

2007, 28(2):  249-252.  doi:10.3969/j.issn.1000-1093.2007.02.028

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A new method of load separation from the head of AUV (autonomous underwater vehicle) was proposed. Based on the dynamic equations given, a set of transform models for the beginning posi-tion of the separated load and the carrier were deduced. A particular measure was given to the new method of load separation. The load turns around an axis at the top of the head of AUV with the buoyancy of the Ioaa itself firstly and then makes a thorough separation from the AUV. This is desir-able because the load has the motion away from the carrier having appropriate pitch attitude, thus re-ducing the chance for the separated load to knock against the AUV. Results of subsequent simulation show that the new method of load separation is safe and easily applied.

A Study on the Crystallization Behavior of ZnO-Al2O3 -S1O2 Transparent Glass- Ceramics

HOU Zhao-xia, SU Chun-hui, ZHANG Hua-shan，ZHANG Hong-bo

2007, 28(2):  253-256.  doi:10.3969/j.issn.1000-1093.2007.02.029

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Li2O-ZnO-Al2O3-Si02 glass was melted in a platinum crucible at 1600℃ for 2 h，and then a two-step heat treatment for the nucleation and crystal growth was used to prepare transparent glass- ceramics. The characterizations were performed by differential thermal analysis, X-ray diffraction, Fourier transmission infrared spectroscopy, scanning electron microscopy and UV-Vis-NIR scanning spectrophotometer. Only one crystal phase namely cubic gahnite ZnAl2O4 exists when heat-treated be-low 970 ℃，and tetrahedral [B-quartz phase begins to precipitate at 970℃ and becomes the main crystal phase at 1100 ℃，at the same time, gahnite ZnAl2O4 becomes the minor crystal phase. The grain size distributes normally, and the standard deviation increases with the heat treatment temperature increas-ing. The lattice parameter of cubic gahnite calculated by the XRD data is 0.809 3nm( 士 0.0007)， which is very close to that of the standard sample.