Table of Content

31 December 2015, Volume 36 Issue 12

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Paper

Spherical Cavity-expansion Model for Concrete Targets Based on Cap Model and Penetration Resistance Analysis

LIU Zhi-lin， SUN Wei-wei， WANG Xiao-ming， FENG Jun

2015, 36(12):  2209-2216.  doi:10.3969/j.issn.1000-1093.2015.12.001

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In order to obtain the resistance equations of high-velocity projectile penetration into concrete targets, a dynamic spherical cavity-expansion model based on cap model is proposed. The general dynamic response expressions of concrete, which are applied to all kinds of spherical cavity expansion model, are obtained by describing the dynamic mechanical behaviors of concrete material with general equation of state and yield criterion. Yield softening properties of concrete under high pressure are considered in the proposed cavity expansion model by introducing the Drucker-Prager cap model. The calculated results show that the resistance equations of high velocity stage derived using Mohr-Coulomb yield criterion with shear saturation and Tresca criterion are great different from those derived using the cap model. The predictions obtained from the cap model are in good agreement with experimental data.

Study of Adjusting Diesel Fuel Supply System in Plateau Area

REN Zhao-xin， SU Tie-xiong， WANG Zeng-quan， YU Bao-jin， DING Ji-feng

2015, 36(12):  2217-2223.  doi:10.3969/j.issn.1000-1093.2015.12.002

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For the reliability problems of diesel engine in plateau area, such as cylinder head ablation and so on, the simulation investigation is made on the maximal fuel supply of injection pump and the different structures of injector nozzle. The effectiveness of the method to control the thermal load of engine in plateau environment is verified by adjusting the fuel supply parameters without modifying the engine structures. A plateau adjustment scheme of fuel supply system is presented, which includes decreasing the largest supply of the fuel pump properly, increasing the number of the jet holes, and reducing the diameter of jet holes and the spray angle of injector, by performance optimization experiment. The proposed scheme can be used to reduce the heat load of diesel engine and improve the reliability of diesel engine in plateau environment. The results show that the power output of diesel engine is dropped by 27% at high altitude of 4 500 m, and other control parameters are in the limited range.

Measurement of Motion Characteristics on Human-rifle System Based on the Combination of Micro Inertial Motion TrackerInstrument and High-speed Photography

GONG Peng-han, ZHOU Ke-dong, KANG Xiao-yong, HE Lei

2015, 36(12):  2224-2230.  doi:10.3969/j.issn.1000-1093.2015.12.003

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The motion parameters of human-rifle system are the important basis of weapons ergonomic evaluation and human-rifle system dynamics modeling in the process of automatic weapon shooting. In order to obtain the motion characteristics of the human-rifle system and quantitatively estimate its motion parameters during shooting of a bullpup rifle, a new method is explored for measuring the human-rifle system, which is a high-speed photography combined with inertial measurement of motion tracker instrument（MTI）. The proposed method is to use the motion information of motion feature points of human-rifle system taken by a high-speed camera to obtain the motion law of the human-rifle system in the pitching through the correlation processing, and the muzzle response of the rifle is measured using MTI inertial measuring instrument at the same time. The motion results at the pitching angles measured by high-speed photography and MTI are compared and analyzed. The experimental results show that the results measured using high speed photography and MTI are believable.

Research on the Performance Decay Rule of Large Caliber Machinegun Barrel

QIAO Zi-ping， LI Jun-song， XUE Jun

2015, 36(12):  2231-2240.  doi:10.3969/j.issn.1000-1093.2015.12.004

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In order to study the erosion rule of large caliber machinegun barrel in lifetime and find out the determinants of barrel life, the life test was done on two barrels made of different materials. The fundamental cause of the ellipse shot holes due to the erosion of the forth and fifth tapers are found out by analyzing the relations among the barrel life and the changes of bore land diameter and bore surface topography, accuracy and dispersion, decreased rate of muzzle velocity and number of ellipse shot holes, which results in the different life of two barrels; when firing 1 200 shots, the chrome layer in the fifth taper of bore fell off, the bore diameter measured by gauge can’t reflect barrel performance, but the barrel life is determinated by the changing of land diameter in the rear of barrel.

The Application of Reverse Jet Gas Technology in Improving Firing Accuracy of a Machine Gun System

HUA Hong-liang， LIAO Zhen-qiang， SONG Jie， QIU Ming， XIAO Jun-bo

2015, 36(12):  2241-2246.  doi:10.3969/j.issn.1000-1093.2015.12.005

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The reverse jet gas technology is proposed to improve the firing accuracy of a 12.7 mm heavy machine gun system. The nozzles are designed at the different positions of the gun barrel, and 3 operating modes of nozzles are then designed for comparison. An accurate rigid-flexible coupling multi-body model of the machine gun system is then established based on related experimental data，and the muzzle dynamic responses are obtained through dynamic simulation. Based on the exterior ballistic theory and the boundary conditions, the bullet dispersions are obtained with a firing distance of 100 m, and the improved conditions of the firing accuracy of the machine gun system are compared. The results show that the initial displacement, firing angle and velocity are stable with little fluctuation when the nozzle thrusts form a moment. The radius of 50% scattered circle is decreased by about 72.3%. The reverse jet gas technology can effectively improve the firing accuracy of the machine gun system.

Simulation of the Characteristics of Backscattering Signals for Frequency Modulated Continuous Wave Laser Fuze

CHEN Hui-min, LIU Yang, ZHU Xiong-wei, WANG Feng-jie

2015, 36(12):  2247-2253.  doi:10.3969/j.issn.1000-1093.2015.12.006

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Frequency modulated continuous wave (FMCW) laser fuze has better resistance to interference than the pulse laser fuze, but it is still affected by cloud and fog. As the backscattering laser signals from cloud and fog may cause a false alarm and the laser power is attenuated by the scattering and absorption of the particles. In order to study the characteristics of echo for FMCW laser fuze, the Monte Carlo simulation model for FMCW laser fuze is built based on FMCW laser detection principle and Mie scattering theory. In the case of FMCW laser fuze and the target in the cloud and fog, the backscattering signals are simulated under the different visibility, and the influences of visibility in cloud and fog on FMCW laser fuze backscattering signals are analyzed. The proposed simulation method can be used to optimize the parameter of FMCW laser fuze for the improvement of the anti-interference ability.

Simulation Study of Bearing Band Engraving Process and Interior Ballistic Process Based on Thermo-mechanical Coupling FEA Model

DING Chuan-jun, ZHANG Xiang-yan

2015, 36(12):  2254-2261.  doi:10.3969/j.issn.1000-1093.2015.12.007

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In order to study the dynamic interaction process of bearing band and barrel, a thermo-mechanical coupling finite element analysis (FEA) model is established. The engraving process of bearing band and interior ballistic process are simulated by the explicit finite element method with the use of Fortran subroutines. The FEA model is proved to be effective by comparing the calculated results with experimental results. The calculated results show that the coefficient of secondary work varies as a function of time, and an extremum value appears in the early time when using classical interior ballistic equation.The thermal softening of bearing band surface has a significant effect on the interior ballistic process during the band engraving. For fixed cartridge case,the computational accuracy of the engraving process and the interior ballistic process could be improved by taking account of extracting bullet force.

Effect of Phantom-bit Technology on Guidance Performance of Phased Array Radar Seeker

LU Tian-yu， YIN Jian， DU Xiao， XIA Qun-li

2015, 36(12):  2262-2268.  doi:10.3969/j.issn.1000-1093.2015.12.008

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To study the effect of phantom-bit technology for phased array radar seeker (PARS) on missile guidance system, the cause of boresight error slope (BSES) is discussed according to the principle of antenna element shift phase, the transfer function of line-of-sight rate containing BSES is derived under the disturbance of missile body, and the change rules of amplitude and phase angle are analyzed. A model of BSES parasitic loop is established based on the pointing angle of beam space, and the effect of phantom bit number (PBN) on the stability boundary of parasitic loop is studied with Routh criteria. Under the condition of the typical radar noise input, the dimensionless and adjoint methods are used to research the influence of PBN on miss distance. The result shows that phantom-bit technology of PARS leads to BSES；the larger the PBN is, the bigger the BSES is, the easier the parasitic loop loses its satbility, and the larger the miss distance is. The receiver noise has a greater effect on miss distance compared to target glint noise under the same condition. Therefore an error calibration method, which is used to calibrate the error among different beam angle directions according to different PBNs, needs to be studied to reduce BSES and improve the accuracy of missile terminal guidance.

Research on Dynamic Response of Launching Site Based on Different Interlayer Binding States

ZHOU Xiao-he， MA Da-wei， ZHU Zhong-ling, LIAO Xuan-ping, JU Xiao-jie

2015, 36(12):  2269-2277.  doi:10.3969/j.issn.1000-1093.2015.12.009

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To obtain the dynamic response of the launching site under the different binding states of base and surface layers, an interlayer binding mathematical model of base and surface layers is established based on bilinear cohesion constitutive of cohesive element. A cohesion mathematical model under different binding states of base and surface layers is established by introducing the initial damage variable and using the strain equivalence hypothesis. A numerical model of launching site under different binding states of base and surface layer is built based on the numerical model with interlayer effect, the distribution and evolution of damage on base-surface layer interface of the launching site below the bottom of launch canister are analyzed, and the dynamic response of the launching site under different binding states of base and surface layer is researched. The result shows that, when the base-surface layer binding state remains constant, the interface damage is the most serious in the base layer where the boundary is forced by the load applied by the bottom of the launch canister, and the interface damage of the base layer firstly increases and then decreases along the radius direction of the load area. When the binding state of base and surface layer gets worse,the interface damage of the base layer is invariant in the middle and decrease on both sides along the radius direction of the load area, the vertical and horizontal displacements of the launching site surface get larger in different degrees, and the maximum stresses of the surface and base layers center-bottom points get smaller.

The Effect of Atmosphere Boundary Layer on Airborne Space Laser Communication and Its Compensation Technology

GAO Tian-yuan, HU Yuan, JIANG Hui-lin, WANG Zhi-jian

2015, 36(12):  2278-2283.  doi:10.3969/j.issn.1000-1093.2015.12.010

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With the development of space laser communications technology, the atmospheric environment has a prominent effect on the airborne space laser communication, and the atmospheric boundary layer is one of the main influencing factors. To study the effect of atmospheric boundary layer on the communication, the influence of the boundary layer is discussed based on the airborne laser communications experiment and the theory of diffraction optics. The results show that the effect of atmospheric boundary layer on the space laser communications system is due to attaching a negative lens with focal length of -530 m in front of the system to cause the change of system focal length and the spot diffusion. The effect can be compensated by increasing a compensative lens in the system, and the corresponding compensation tests are carried out. The results show that the effect of the atmospheric boundary layer on the space laser communication can be compensated by optical method, and the compensation meets the requirements of space communication.

Coalition Formation of Multiple Heterogeneous Unmanned Aerial Vehicles in Cooperative Search and Attack in UnknownEnvironment

LIU Zhong, GAO Xiao-guang, FU Xiao-wei, MOU Zhi-ying

2015, 36(12):  2284-2297.  doi:10.3969/j.issn.1000-1093.2015.12.011

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A novel method for coalition formation of multiple heterogeneous unmanned aerial vehicles in cooperative search and attack in unknown environment is presented to improve the cooperative search and attack effectivenesses of multiple heterogeneous unmanned aerial vehicles. A coalition formation model is established based on the minimum target attack time and the minimum coalition scale with the constraints of required resources and simultaneous strike. A multistage sub-optimal coalition formation algorithm (MSOCFA) that has low computational complexity is proposed to solve the optimization problem of coalition formation. The performances of MSOCFA and partical swarm optimization algorithms are compared in terms of mission performance, complexity of algorithm and time taken to form the coalitions. In order to enable the multiple cooperative unmanned aerial vehicles to accomplish the search and attack missions autonomously, a distributed autonomous control strategy is proposed, which is based on the finite-state machine (FSM). The simulation results show the rationality, validity and high real-time performance of the proposed method for the coalition formation of multiple heterogeneous unmanned aerial vehicles in cooperative search and attack in the unknown environment. Monte Carlo method is employed to validate the impact of the number of unmanned aerial vehicles and targets on coalition formation. The reduced average mission completion time relates to the decreased number of targets and the increased the number of unmanned aerial vehicles.

An Algorithm for Convolutional Codes Recognition Based on Sectionally Extracting Soft-decision Weighted Walsh HadamardTransform

ZHANG Dai, ZHANG Yu, YANG Xiao-jing, FAN Bin-bin

2015, 36(12):  2298-2305.  doi:10.3969/j.issn.1000-1093.2015.12.012

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An algorithm for convolutional code recognition based on sectionally extracting soft-decision weighted Walsh Hadamard transform(WHT) is proposed for the issue of convolutional code recognition in the low signal-to-noise ratio(SNR) environment. The proposed algorithm is used to obtain a soft-decision frequency sequence by using received bits’ soft-decision information, and construct a weighted Walsh Hadamard matrix to recognize the basic check sequence. The code memory length and basic generated matrix are recognized based on the construction rule of basic encoding matrixt. The algorithm has the reduced run storage space. Simulation results show that the algorithm could recognize the convolutional codes with different coding rates in the low SNR environment, and has good fault-tolerant performance, which is improved greatly especially in recognition of long restraint-length convolutional codes.

Real-time Visualization of Electromagnetic Situation with Graphics Processing Unit Based on Ray-casting Algorithm

GAO Ying， CHEN Xu， ZHOU Shi-jun， GUO Shu-xia

2015, 36(12):  2306-2314.  doi:10.3969/j.issn.1000-1093.2015.12.013

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The battlefield electromagnetic situation has the characteristics of complexity, multidimensions and time-varying. Real-time visualization of battlefield electromagnetic situation is significant for commanders to make scientific decisions. Currently, the battlefield electromagnetic data models are not perfect. A mathematic model of the field strength of multiple radiation resources is established by taking the field strength for example, which is used to provide the data sources for constructing 3D volume data field of the battlefield electromagnetic situation. The traditional central processing unit (CPU)-based algorithm cannot meet the requirement of real-time solution because of the complexity of mathematical models related to the volume data field. A volume data field accelerated generation technique based on general purpose graphics processing unit (GPGPU) is proposed. The experimental results show that the proposed technique can meet the requirement of real-time visualization compared to the traditional algorithm. A transfer function is designed to accomplish the visualization of electromagnetic situation based on GPU ray-casting algorithm.

Optimization of Polyphase Codes for Anti-deceptive Jamming of Synthetic Aperture Radar

YAN Jia-bing, LI Wei, LAN Xing, WU Hao-tian, ZHANG Qun

2015, 36(12):  2315-2320.  doi:10.3969/j.issn.1000-1093.2015.12.014

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Deceptive jamming for synthetic aperture radar(SAR) can get the compression gains of range and azimuth direction, and the performance of SAR can be affected by low power. An anti-jamming method based on the agility of multiple orthogonal phase codes between neighboring pulses is proposed for the deceptive jamming suppression of SAR. The long polyphase codes are optimized based on weighted cyclic algorithm to increase the of the auto-correlation peak of codes and decrease the sidelobe of correlation function and the peak of cross-correlation function. As a result, the performance of anti-repeater jamming is enhanced. The comparison between the performances of auto-correlation and cross-correlation of polyphase codes optimized using simulated annealing algorithm, genetic algorithm and the proposed methodr are compared by simulation. The anti-jamming performance of polyphase code is compared with that of the biphase codes under various jamming powers. The results show that the proposed can be used to achieve a detection probability of 88% even at jamming power of 20 dB.

Joint Sparse Recovery Estimation of Underwater Acoustic Single-input-multiple-output Channels

ZHOU Yue-hai，CAO Xiu-ling，TONG Feng，CHEN Dong-sheng

2015, 36(12):  2321-2329.  doi:10.3969/j.issn.1000-1093.2015.12.015

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Underwater single-input-multiple-output (SIMO) system enables the exploitation of space diversity to achieve performance enhancement. Considering that the vertical correlation radius of underwater channels is usually larger than the distance between array elements, the sparse structures of SIMO channels response exhibit considerable correlation feature. A channel estimation algorithm under the framework of distributed compressed sensing（CS）is presented to perform the joint sparse recovery estimation of SIMO channel via simultaneous orthogonal matching pursuit (OMP). Compared with the traditional CS channel estimation algorithms which only exploit the sparsity of single channel, the proposed algorithm is capable of employing the joint sparse correlation of SIMO channels to improve the performance of SIMO channel estimation. The simulation and field experimental results show that the proposed algorithm effectively improves the performance of SIMO channel estimation in terms of estimation accuracy and communication quality, especially under low signal-noise ratio.

Noise Reduction of Chaotic Signal Based on Auxiliary Sigma Point Particle Filter

YANG Hong， LI Ya-an， LI Guo-hui

2015, 36(12):  2330-2335.  doi:10.3969/j.issn.1000-1093.2015.12.016

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In order to solve the problem of that the traditional extended Kalman filter and unscented Kalman filter methods cannot effectively suppress the additive noise of the chaotic system, an improved particle filter algorithm is presented. The state space description of the chaotic system is derived in detail, and a noise reduction method of chaotic signal based on auxiliary sigma point particle filter is proposed. As an example，Lorenz chaotic signal is used to evaluate the efficiency of the proposed algorithm. The results show that the proposed algorithm has obvious effect on noise reduction for Lorenz chaotic signal with noise.

Research on Comprehensive Scheme of Shipboard Hard and Soft Torpedo Defense Weapons against Intelligent Torpedoes

REN Lei， JIA Yue， LI Wen-zhe

2015, 36(12):  2336-2341.  doi:10.3969/j.issn.1000-1093.2015.12.017

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A countermeasure method of hard and soft torpedo defense weapons, i.e., floating acoustic decoy and suspended depth charge, against acoustic homing torpedoes is proposed. The launching sequence is determined, and two possible laying schemes are presented. The countermeasure effects of the two schemes are simulated by using statistical simulation method. An optimal scheme to use the shipboard hard and soft torpedo defense weapons against intelligent acoustic homing torpedoes is chosen through analysis. The survival probability of ship is effectively improved by improving the laying interval between floating acoustic decoy and suspended depth charge.

Drilling Experiment of Laminated Composites by Ultrasonic Vibration Assisted Helical Milling Method

GAO Hang， SUN Chao， RAN Chong， ZHANG Xin， LI Li-li

2015, 36(12):  2342-2349.  doi:10.3969/j.issn.1000-1093.2015.12.018

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An ultrasonic vibration assisted helical milling method is proposed for machining 40CrNiMoA/glassfiber reinforced plastics (GFRP) laminated composites. The tool trajectory of ultrasonic vibration assisted helical milling method is analyzed, and the ultrasonic vibration amplitude range of effective machining is deduced. The cutting force, cutting temperature and machining quality of three different machining method under the same tool cutting speed and machining efficiency are analyzed. The results show that, compared with the traditional helical milling and drilling，the cutting forces of ultrasonic vibration assisted helical milling of 40CrNiMoA are reduced by 25% and 40%, respectively; while the maximum cutting temperatures are decreased by 15.7% and 22%. When processing GFRP, the maximum temperature is reduced by 16.5% and 50%. Meanwhile, the hole walk surface quality is significantly improved, the manufacturing defects, such as tearing and burrs, are significantly reduced to reach the manufacturing requirements.

Study of Properties of Quartz/POSS Modified Silicone Wave-transparent Materials

WEI Hua-zhen, LI Ying, KONG Guo-qiang

2015, 36(12):  2350-2357.  doi:10.3969/j.issn.1000-1093.2015.12.019

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A kind of wave-transparent composite is made by using glycidyl POSS as modifier, poly(methylphenylsiloxane) as matrix resin, quartz fiber as reinforcing agent，and its mechanical and dielectric properties are studied. The results show that the compressive strength and bending strength of quartz/POSS modified silicone composite are 71.4 MPa and 137.0 MPa, respectively. The composite has excellent dielectric properties with dielectric constant of less than 3.3 and dielectric dissipation factor of less than 0.007 at 8.7 GHz and temperature from room temperature to 600 ℃. It is a multifunctional composite, including heat protection, wave-transmission and load carrying.

Effect of Excess Air Ratio and Ignition Timing on Performance of M100 Methanol Engine

WANG Yan-peng，WANG Zhong，ZHANG Deng-pan，JU Yu-sheng，ZHANG Yong-ming

2015, 36(12):  2358-2362.  doi:10.3969/j.issn.1000-1093.2015.12.020

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The effects of excess air ratio and ignition timing on engine torque and break specific fuel consumption of a methanol engine transformed from a gasoline engine are studied, and the performance of M100 methanol engine is experimentally investigated. Results show that the engine torque increases with the increase in advanced ignition angle for a specified excess air ratio at 2 500 r/min, and the NO emission is increased by 80% when the fuel consumption decreases. When the excess air ratio decreases at a specified ignition time，the engine torque increases, and HC and CO emissions are significantly increased. The maximum torque is increased by 5.2% higher than that of original gasoline engine, and the brake specific fuel consumption is lower at speed of 2 000 r/min.

Research on Flow Resistance Coefficient and Opening Force of Deep Diving Outboard Pilot-operated Valve

LIU Shao-gang，ZHENG Da-yong，CHENG Qian-ju

2015, 36(12):  2363-2368.  doi:10.3969/j.issn.1000-1093.2015.12.021

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The flow resistance coefficient and opening force are the most important parameters for the evaluation of valve performance. In consideration of the influence of noise reduction optimization on the internal flow passage of pilot operated valve, the CFX software is used to simulate and analyze the flow resistance coefficients under different external working pressures and openings. The analysis results show that the flow resistance coefficient of optimized flow passage is less than that of the original flow passage for the valve under low and full openings. The valves with and without pilot hole are also statically analyzed by CFX software under different openings. the surface groups for extracting are determined according to the influence surface of actual valve rod axial force, and the axial forces of valve rod in different positions are obtained. The analysis results indicate that the pilot hole can reduce the opening force, and the maximum opening force of value with pilot hole is an half of that of value without pilot hole. The simulated opening force is validated by experiment, and the experimental result is consistent with the simulation result.

Mechanical Contact Mechanics of Water Lubrication Rubber Stave Bearing and Cu Backing for Ship Stern Tube

TIAN Hong-liang， ZHENG Jin-hua， QIN Hong-ling

2015, 36(12):  2369-2380.  doi:10.3969/j.issn.1000-1093.2015.12.022

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The theoretical solutions for normal contact load, real contact area, real elastic contact area, real plastic contact area and rubber plasticity index in the contact of rubber stave bearing and Cu backing are constructed by considering the elastic and plastic deformation zones of microcontacts based on statistical analysis of wiggly and jagged surface micro geometric morphology. The calculation and analytical results show that the expected number of contacts increases with the increase in normal contact load and increases slightly with the increase in apparent contact area. The separation between rubber stave bearing and Cu backing decreases with the increase in normal contact load, and gains with the increment of apparent contact area for a given normal contact load. For a given apparent contact area, the real contact area is almost exactly proportional to normal contact load but doesn’t depend on apparent contact area. The average real contact pressure is aggrandized with the augment of normal contact load and lessens with the increase in apparent contact area. The contact resistance between contact surfaces diminishes as the normal contact load increases. When the rubber plasticity index is less than 1.77 or metal plasticity index is less than 0.6, the elastic deformation is caused on contact surfaces. When the rubber plasticity index exceeds 2.95 or the metal plasticity index is larger than 1.0, the plastic deformation occurs on contact surface. The related model and simulation curves lay a theoretical foundation for the accurate solution of elastic and plastic contact about rubber harsh surface.

Research Notes

Research on Internal Ballistics Design Method of Water-projectile Test after Gun Repair

FU Jian-ping，ZHANG Ze-feng，YU Jia-wu，LI Lei

2015, 36(12):  2381-2385.  doi:10.3969/j.issn.1000-1093.2015.12.023

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Gun water-projectile test is widely used to determine its technology state and inspect its repair quality after repairing. It is difficult to determine the key internal ballistic parameters in the mass of water-projectile because an internal ballistics design method on water-projectile test lacks for the new guns, which is restricted to carry out water-projectile test. An internal ballistics model of water-projectile test is established based on the principle of water-projectile test and its engineering practice. The internal ballistics design method based on the impulse equal principle of gun bore resultant forces in water-projectile test and live firing is introduced. The research result can preovid theoretical guidance for water-projectile test after new gun repair, and provide the reference for the water-projectile test of the other assessment purposes.

Research on Optimal Search Path Programming in Continuous Time and Space Based on an Adaptive Genetic Algorithm

ZHANG Xian， REN Yao-feng， WANG Run-peng

2015, 36(12):  2386-2395.  doi:10.3969/j.issn.1000-1093.2015.12.024

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A Markovian-target model based on stochastic differential equations and a path programming model with both searcher’s direction and velocity treated as decision variables are presented for optimal searcher path problem in continuous time and space, and the effect of searcher’s velocity on the detection ability is considered. A genetic algorithm with adaptive mutation is designed by introducing three kinds of control factors, which fulfills the adaptive control of the direction and range of mutation and dynamically regulates the balance between local search and global search. In an example of searching a target with a random escaping direction, an approximate logarithmic spiral path is found. Moreover, the algorithm provides a reasonable and effective search scheme in a path programming problem for a helicopter searching multiple targets. The results indicate that the proposed algorithm has the significant advantages of stability and global optimizing ability in comparison with other methods, and is well suitable for the search path programming problem in continuous time and space.

Research on Digital Pattern Automatic Painting System

XIE Wei，ZHOU Zhi-yong，CAI Yun-xiang，MU Jing-yang

2015, 36(12):  2396-2400.  doi:10.3969/j.issn.1000-1093.2015.12.025

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Digital pattern is a new camouflage technique, which has better camouflage effect. For the problem of low efficiency of artificial painting，four detection techniques, such as the 3D square grid modeling of military equipment, the 3D digital pattern model generation, the spraying automatic path planning and the real time detection of lance position, are solved. A digital pattern automatic painting system is constructed. Test results show that the application of automatic system can effectively improve the painting efficiency of digital pattern, and promote the further development of digital pattern technology.