Table of Content

30 November 2009, Volume 30 Issue 11

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Paper

Experiment Study on Coupled Characteristics of High-Low Fuel Ducts of DDC2000 Diesel’s EUP

QIU Tao，LIU Xing-hua, LU Ying, YIN Wen-hui

2009, 30(11):  1409-1412.  doi:10.3969/j.issn.1000-1093.2009.11.001

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The coupled experiment of high-low pressure fuel pipe of the DDC 2000 diesel’s EUP was conducted; the influences of return fuel of high pressure pipe on feed fuel of low pressure, low pressure fuel pipe on characteristic of high pressure injection were analyzed. The experimented, and analyzed re?sults show that if the low fuel pressure changes suddenly in the fuel-filled process for EUP, it will in?crease the cyclic variation of EUP injection characteristics and maybe cause the instability in the jet; with the camshaft speed increasing, the lack of fuel-filled becomes serious; the improved fuel supply pressure of low pressure fuel pipe is helpful to improving fuel supply pressure stability of fuel pump, preventing its abrupt change; the critical fuel supply pressures corresponding to different rotational speeds are different, which increase with the increases of the speeds.

Thermal Analysis for Hydrodynamic-Mechanical Transmission of Tank

BI Xiaoping, XU Xiang, WANG Pu-kai, SUO Wen-chao

2009, 30(11):  1413-1417.  doi:10.3969/j.issn.1000-1093.2009.11.002

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Considering comprehensively interference among the components in hydrodynamic mechani?cal transmission and influences of lubricating oil, the air in powerplant compartment and hull on the transferee! heat, a whole thermal analysis model was established, which consists of the generated heat models and the transferee! heat model of the components such as gearbox, hydrodynamic torque con-verter, transmission and final gearbox. The thermal analysis was accomplished for tank mechanical drive and hydraulic drive work conditions, and heat generation quantity and heat transfer quantity for transmission device and detailed temperature distribution for components were obtained. The compari-son between the analyzed and the tested temperature values was carried out. The analyzed results show that the maximum relative error of temperatures between the thermo-analyzed and the tested is less than 10 % .

Simulation on Performance of Special Movement of Electric Transmission Tracked Vehicle Based on VirtualPrototyping

WANG Shuang-shuang, ZHANG Yu-nan, YAN Nan-ming,ZHAO Yu-hui, ZHANG Liang

2009, 30(11):  1418-1423.  doi:10.3969/j.issn.1000-1093.2009.11.003

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In order to evaluate the performance of electric transmission tracked vehicle, models of mo?tor driving system and dynamics of the 20 ton tracked vehicle were constructed by virtual prototyping, which compose the model of mechanical-electric collaborative simulation. Special movements such as central steering, overpassing cliff and entrenchment were simulated and evaluated. The results show that performance of vehicle can meet designed demand, the method of collaborative simulation settles the technique basis for performance forecast and evaluation of electric transmission tracked vehicle.

Experimental Research on Noise Source Identification and the Radiation Characteristics of a Gearbox Based on NAH

XIANG Chang-le, CHEN Fu-zhong, LIU Hui,ZHANG Xi-qing

2009, 30(11):  1424-1429.  doi:10.3969/j.issn.1000-1093.2009.11.004

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The method of near-field acoustic holography (NAH) was applied to identify the noise source of a certain vehicle gearbox. The main internal excitation sources and the external radiation sources of noise were located by analyzing sound power spectra and holograms of the gearbox surfaces. On that basis, main rules and influence factors of the noise radiation were obtained through discussing radiation characteristics of the gearbox. The experimental research lays a solid foundation for the fur?ther research of noise reduction of the gearbox.

Research of Maintainability and Validation Methods in Armored Equipment Based on Virtual Maintenance

CUI Xiaofeng，FENG Wu-bin, XIANG Chang-le,WANG Zhan-jun, HAO Hui-bing

2009, 30(11):  1430-1434.  doi:10.3969/j.issn.1000-1093.2009.11.005

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Based on the VR technology and maintenance engineering theory, the simulation platform of armored, equipments’ virtual maintenance was established in order to realize process simulation of non- immerse virtual maintenance. V isual reachability of every maintenance unit during maintaining was e- valuated quantitatively by constructing visual inner-cone of the virtual human model, and visual reacha?bility of a certain maintenance was evaluated quantitatively by the fuzzy mathematical theory. Ine fea?sible method can be provided for analyzing and validating quantitatively qualitative index of visual reachability in the early period of scheme demonstration, research and development of new armored e- quipments.

Diagnosis and Judgment of Transient and Small-size Plasma with Spectroscopic Method

ZHANG Lin, FENG Hong-yan, WU Rong,ZHU Shun-guan

2009, 30(11):  1435-1439.  doi:10.3969/j.issn.1000-1093.2009.11.006

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A ignition pattern of taking plasma as excitation energy is a developing ignition technique for energetic materials, which parameters, such as plasma temperature and electron density, are very im?portant for the illumination of ignition mechanism. As plasma generated by semiconductor bridge (SCB) is transient and small size, many measurement methods are unsuitable. Then SCB plasma tem?perature and electron density were diagnosed simultaneously with atomic emission spectroscopy (AES)，which of 1.0 Ω are between 2 400 K and 3 800 K and. 3.2 X IO14?4? 2 X IO14 cm 3 under the conditions of the discharge voltage of 16 V and the charge capacity of 47 μF. It was judged, whether discharge behaviors of the different type SCBs generate plasma, by space and time dimensions and AES. The investigated results can provide an effective method for diagnosing transient and small size plasma, theoretical instruction and reference basis for designing SしB and controlling ignition pattern, and diagnosis and judgement of plasma parameters for the other systems.

Guaranteed Cost Control for Multiple-Packet Transmission Networked Control Systems

XIE Cheng-xiang, HU Wei-Li

2009, 30(11):  1440-1445.  doi:10.3969/j.issn.1000-1093.2009.11.007

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The problem of guaranteed cost control for a class of multi-packet transmission networked control systems with uncertain short time-delay was studied. Under the condition of static schedule of sensor data transmission, a model was introduced in the controller node to predict the plant state, its state was updated using the received sensor data, then the multi-packet transmission networked control system was modeled as a linear discrete periodic system with uncertainties. The existence condition of guaranteed cost control law was derived according to periodic system theory and matrix inequality method, and the design method of guaranteed cost controller was also presented. The suboptimal guar?anteed cost control law and suboptimal cost index was obtained through solving optimize problem con?strained by bilinear matrix inequalities using PENBMI software. The simulated results by an example show the validity of the proposed, method.

Analysis on the Observability for Continuous Bearings-only System

LI Hong-rui, SHENG An-dong

2009, 30(11):  1446-1450.  doi:10.3969/j.issn.1000-1093.2009.11.008

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It was proved that a continuous bearings-only observation system is observable if and only if an observable discriminant which only consists of four bearings without their differentiating and the so?lution of differential equations is not equal to zero. Observer motion equations for the unobservable sys?tems were given and analyzed, the analyzed results show that a system is unobservaole if and only n for all bearing measurements the observer trajectory is equivalent to an uniform line. A criterion of target maneuver detection was presented by the mentioned above conclusions under the restriction of uniform live motion of target.

Blind Source Separation of the Array Signal in the Fractional Fourier Domain

DENG Bing, TAO Ran, YIN De-qiang

2009, 30(11):  1451-1456.  doi:10.3969/j.issn.1000-1093.2009.11.009

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A novel blind source separation method was proposed based on array average in the fractional Fourier domain, which introduces a set of weighting function into the fractional Fourier domain to de?crease the noise level and interaction among the source signals. Compared with the traditional blind source separation method, the proposed method does not require whitening and joint-diagonalization to the hybrid matrix, has lower complexity, small amount of operation and good anti-jamming capability.

A Novel Framework of the Mathematical Model and Ambiguity Function for a Bistatic Detection System

GUO Qiang, LI Wei-feng, MA Chang-zheng，DONG Xiu-jie, TAORan, WANG Yue

2009, 30(11):  1457-1462.  doi:10.3969/j.issn.1000-1093.2009.11.010

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Echo model and ambiguity function for a slowly fluctuating moving target were established by the distance r between the target and the reference point at wmch the target moving direction in?tersects the baseline, the angle a between the target moving direction and the baseline, the ratio n in which the baseline is divided by reference point and the baseline range L as arguments in any bistatic triangle plane. The signal delay at receiver was approximately calculated using Taylor series expansion which was derived by T. Tsao. Based on the model above mentioned, the ambiguity function is more of universal significance and simplified because of the randomicity of reference point target and hypoth?esized point target selected and no north-referenced coordinate system required.

Forecast Model and Error Analysis of the Line-of-Sight Angular Speed of Short Range Missiles

LI Yi, LI Zhao, LIU Jun-chen

2009, 30(11):  1463-1468.  doi:10.3969/j.issn.1000-1093.2009.11.011

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For the short range missile adopting open-loop control flies along the forecast line-of-sight (LOS), the forecast precision determines the missile hit precision. In order to study the influence of the LOS angular speed forecast error on the guidance precision, the forecast model and forecast error model of the LOb s angular speed were established, based on the coordinate transformation principle of strapdown inertial guidance system; the influences of the error source on forecast error and hit pricision were simulated and analyzed; the precision match and require ment of inertial devices were proposed. The investigated results provide theoretical basis for studying missile error model and the method of re?ducing and compensating error.

Influences of Technological Parameters on Tribological Properties of Ni-Base Alloy Strengthening Coatings by Electro Spark Deposition

TAN Ye-fa, CAI Bin, XU Ting,CHU Wei-jun, JIANG Guo-liang, TAN Hua

2009, 30(11):  1469-1472.  doi:10.3969/j.issn.1000-1093.2009.11.012

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In oraer to prepare high quality alloy strengthening coatings and improve their tribological properties, the Ni-base alloy strengthening coatings were prepared by electro-spark deposition. Influ?ence of technological parameters on tribological properties of the Ni-base alloy coatings were studied in detail.the researched results show that the parameters such as electro-parameters, specific strength?ening time and flux of argon gas have important effects on tribological properties of the Ni-base alloy coatings; the microstructure of Ni-base alloy strengthening coatings prepared by low value of output voltage (110 V) and relative big capacitance volume 1300 μF) is dense and have good property of wear resistance; the proper specific strengthening time of 2.5 min/cm2 and the argon gas flux of 5 L/min were adopted to prepare the Ni-base alloy coatings, which can result in dense and uniform microstruc?ture, decrease friction coefiicient.and increase wear resistance. The wear mechanisms of Ni-base alloy coatings are mainly micro-cutting and micro-fracture wear.

E-Bayesian Estimation Method of Parameter and Its Applications in Reliability Engineering

HAN Ming

2009, 30(11):  1473-1476.  doi:10.3969/j.issn.1000-1093.2009.11.013

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A evaluation method of reliability of industrial products needs to be improved effectively with the advance of science and technology. E-Bayesian estimation method of parameter estimation in relia?bility engineering was proposed. Based on the definition of E-Bayesian estimation of the failure proba?bility, the formulas of E-Bayesian estimation and hierarchical Bayesian estimation of the iailure proba?bility were provided, and the characteristic of the E-Bayesian estimation, 1.e. the relation between E- Bayesian estimation and hierarchical Bayesian estimation, was discussed. The calculated results by the practical problem show that the proposed E-Bayesian estimation method is feasible, and convenient in engineering application.

A New Cepstrum Coefficients Applied to Acoustic Target Recognition

MA Yuan-feng, CHEN Ke-an, MA Miao,ZHANG Cheng

2009, 30(11):  1477-1483.  doi:10.3969/j.issn.1000-1093.2009.11.014

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A kind of cepstrum coefficients based on new feature was presented. Compared with Mel- frequency cepstrai coefficients (MFCC) used extensively at present, it was improved for computing tke new cepstrum feature in acoustic target recognition that I) the bank of trianguiar filters was improved based on cochlear model; 2) the log-compressed was replaced by the exp-compressed which is the func?tion of frequency; 3) the adaptive mechanism was introduced into the process of transformation from frequency domain to perceptual domain. Simulations of the four acoustic target recognition were carried out. The simulated results show that the proposed features have strong anti-noise ability.

Directional Performance of Acoustic Vector Sensors' in Pekeris Waveguide

WU Yan-qun, HU Yong-ming

2009, 30(11):  1484-1487.  doi:10.3969/j.issn.1000-1093.2009.11.015

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The complex acoustic intensity was derived and analyzed for a far-field harmonic point source in Pekeris waveguide. The results of the study show that the instantaneous acoustic intensity flux for each normal mode is the souna energy distribution of a pair of plane waves with the same amplitude and initial phase difference of 丌 in the medium; the interference of each normal mode results in the ex?istence of the horizontal active and reactive acoustic intensity; in the vertical direction, the cancellation phenomenon of acoustic energy flux exists in each normal mode for oneself, but interference of each other leads to the nonzero active acoustic intensity; a 3-D acoustic vector sensor can not identify the point source elevation angle of the radiation harmonic signal by the averaged acoustic intensity method, in the Pekeris waveguide, simulations were conducted by the normal mode code.

Experimental Study on Damping Characteristics of the Twin-tube Magneto- Rheological Fluid Damperwith Disc Type Orifice for the Vehicle

ZHANG Jin-qiu, WANG Hong-tao, FENG Zhan-zong，JIA Jin-feng

2009, 30(11):  1488-1492.  doi:10.3969/j.issn.1000-1093.2009.11.016

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Structure and principle of the Twin-tube Magnetorheological fluid damper (MRD) were de-signed and described. The laws of varying damp force with current, displacement, gap and frequency were investigated by testing for the damper. The tested results show that the damp force increases nonlinearly with the increase of control current; the adjustable coefficients of peak damp force and con?suming energy decreases nonlinearly with the increase of frequency, and increases nonlinearly with the increase of gap. The tested investigation of damping characteristics lays the foundation for the applica?tion of the damper to semi-active control of suspension system of armored vehicle.

Research on Optimization Method for Accelerated Life Test of CQ2-series Cylinder

FU Yong-ling, HAN Guohui, WANG Zhan-lin,CHEN Juan

2009, 30(11):  1493-1498.  doi:10.3969/j.issn.1000-1093.2009.11.017

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Based on optimization model of CQ2-series cylinder, an improved genetic algorithm was de?signed, in which the points of crossover and mutation in the algorithm vary with the population diver?sity function, and during later period of optimization, Powell method was employed for acceleration. The optimization results of the complex function with high dimensions show that the the problem of premature convergence is solved effectively and the optimal value was approached rapidly in later opti?mization, to get global optimum. Accelerated life test of CQ2-series cylinders was conducted based on the optimization scheme. The tested results verily that the scheme can shorten the period and reduce the cost effectively under the premise of without influence on the parameter estimation precision.

Study on the Constant False Alarm Rate Detector Based on Subspace Modeling in LJncertain Waveguide

ZOU Li-na, ZHU Xian, DU Shuan-ping

2009, 30(11):  1499-1503.  doi:10.3969/j.issn.1000-1093.2009.11.018

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The troubles of active sonar faced in the uncertain shallow water waveguide mainly are echo uncertainty and reverberation interference. So a detecting and estimating method by a constant false alarm rate (CFAR) detector for subspace echo was presented. The CFAR detector was structured by the generalized likelihood ratio test (GLRT) theory under the conditions that the echo was modeled as a subspace signal, the reverberation interference was modeled as a like signal one, and the maximum likelihood estimation of the reverberation correlation matrix was substituted into likelihood ratio test. The processed results to the simulated data and the real ones show tKat tKe CFAR detector kas better coherent matching ability to the uncertain channel, better tolerance to the channel uncertainty, by which the better pulse compression effect can be obtained, the target position estimation precision can be improved, and the detection performance can be improved by I - 2.5 dB compared with the conven?tional matching filter.

Nonlinear Flight Control System Design of Bank-to Turn Unmanned Aerial Vehicle

YANG Jun-peng，ZHU Xiao-ping

2009, 30(11):  1504-1509.  doi:10.3969/j.issn.1000-1093.2009.11.019

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A method of designing a bank-to-turn(BTT) flight control system of unmanned aerial vehi?cle (UAV) was studied to solve the problems cause by kinematics coupling, aerodynamic nonlinearity and parameter uncertainty. The zero dynamic system of nonlinear motion of BTT was adjusted for sta?bility augmentation by the quadratic optimum adjustment law; the nonlinear system of BTT was pro?cessed linearly by the precision feedback linearization method; the control law of BTT was designed by a sliding mode variable structure control method to obtain the BTT flight control system with nonlin?earity and robustness. The performance of the control system was analyzed by the digital simulation based on U/vV six-freedom nonlinearly dynamic and kinematic model. The simulated results show that the control system can meet the needs of accuracy and robustness under the condition of perturbation.

Dynamic Reliability Analysis of Mechanical Components

WANG Xin-gang, ZHANG Yi-min，WANG Bao-yan

2009, 30(11):  1510-1514.  doi:10.3969/j.issn.1000-1093.2009.11.020

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The traditional reliability model of components can not well reflect the effect of loads of stochastic-changed amplitude and strength degradation on reliability due to neglecting changes of relia-bility and failure rate with used time. Considering stochastic loads of variable amplitude and strength degradation, a functional equation model for dynamic reliability of mechanical components was estab-lished based on random process and order statistics theory, and then reliability index and dynamic relia-bility of components were obtained according to second order moment method and perturbation method. Variation rules of strength, loads, reliability and failure rate of mechanical components with used time were studied and dynamic curves of reliability and failure rate vs used time were also given. The calculated results by a real example show that the functional equation model established is in accor?dance with practical working conditions, and the dynamic curves obtained possess certain guiding sig?nificance for determining test time and reliable life of comoonents.

Size Effect on Static Mechanics Behaviors of Isolator with Chevron-Shaped Struts

ZHAO Hua, WANG Min-jie, ZHAO Shu-de,CHEN Bo-Ii

2009, 30(11):  1515-1521.  doi:10.3969/j.issn.1000-1093.2009.11.021

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The size effect of structural dimensions on static mechanics behaviors of isolator with dhevron-shaped struts was analyzed by FEM method, and the relationships between plateau-start-force of force/deflection curve and structural dimensions were constructed. Effects of variations of rib-angle, rib-width and rib-height on plateau-start-displacement, plateau-start-force and plateau-length of force/ deflection curve were studied respectively. Based on the results of variations of plateau-start-force with structural dimensions, the relationships between plateau-start-force and structural dimensions were in?vestigated ;the master curve which is used to describe variation of the plateau-start-force with the ratio of rib-height and rib-width was constructed by introduction of the shift factors of rib-width and rib-an?gle, and described by a parabolic function. The variations of plateau-start-force under the different rib- height and n D-width with rib-angle were calculated by the master curve function and analyzed by the FEA. Comparison between the analyzed and the calculated shows the validity of the master curve func?tion. The analyzed results of size effect and the master curve function can provide theoretical direction for designing the isolator.

The Color Coding of Information Based on Different Mental Workload and Task Type

ZHANG Lei, ZHUANG Da-min, WAN-YAN Xiao-ru

2009, 30(11):  1522-1526.  doi:10.3969/j.issn.1000-1093.2009.11.022

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Through analyzing task characteristics in the process of driving aircrafte by pilot, an interac?tive simulation model was developed, wmch contains four display interfaces corresponding to different types of the tasks. The subject s identification situation to the different color codings was evaluated and analyzed by the experiment, in which mental workload is controlled by changing display frequency of task information and correct response rate and reaction time are regarded as performance indicators, to provide a scientific basis for designing ergonomics of information display interface,the experiment?ed results show that the mental workload has different influences on information identification when the color coding schemes are different; the information color coding has different influence when the tasK types are different; the matched background-target colors have significant effect on information identification, wmch are selected according to the different mental workloads and task types.

Comprehensive Reviews

Heat Stress Problem and Solution of Tank & Armored Vehicle Crewmen

GUO Xin-mei, YUAN Xiu-gan

2009, 30(11):  1527-1532.  doi:10.3969/j.issn.1000-1093.2009.11.023

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It was analyzed that heat environment in tank and armored vehicles and NBC protective clothing make crewmen be at high level of heat stress and severely weaken their survivability and fight?ing capacity. The research and development of air conditioning and microclimate cooling used in the tank and armored vehicles for solving the heat stress of crewmen were reviewed. The analyzed and re?viewed results show that microclimate cooling is better than air conditioning in some respects of low power consumption, small size, light weight, simple technology and significant cooling effect (special?ly for crewmen wearing NBC protective clothing)，and a best solution for the heat stress of tank and armored vehicles crewmen so far.

A Survey of the Complex Large System Dynamic Reliability and Dynamic Probabilistic Risk Assessment

TAO Jun-yong, WANG Yong, CHEN Xun

2009, 30(11):  1533-1539.  doi:10.3969/j.issn.1000-1093.2009.11.024

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Complex large system failure often causes huge property loss, and even serious society influ?ence and heavy casualties, the reliability and risk assessment therefore have been widely concerned. In the context of reliability and probabilistic risk assessment of the complex large system, how to consider the influence of the system ’ s dynamic behavior on the system reliability and risk has been a hotspot over the past two decades, and evolved the concept of dynamic reliability and many methods. This pa?per reviewed the concept, the theory ana technology, furthermore introduced the main dynamic relia?bility assessment methods and their application, and provided some help for dynamic reliability study.

Research Notes

A New Parallel Scrambling/Descrambling Method Based on the Property of Sampling Subsequence of m-Sequence

WUWen-jun，TANG Gui-lin，GUO Xiaojun，HUANG Zhi-ping

2009, 30(11):  1540-1545.  doi:10.3969/j.issn.1000-1093.2009.11.025

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In order to solve defect of the scrambling/descrambling method in the current SDH comuni- cation, a new parallel scrambling/descrambling method was proposed. The process of parallel scram?bling/ descrambling is regarded as a sampling process of the m-sequence. When the sampling interval is the power of 2，generated polynome of the sampling subsequence of m-sequence is equivalent to that of the original m-sequence, which have the different initial states respectively. Based on the property, the parallel scrambler can be divided to several scramblers whose parallel word widths are much small?er, to improve operation rate, rhe architecture of this scrambler is simple, has no requirement on memory and can better satisfy the time sequence request of high-speed transport system. The proposed method was realized by field programmable gate array and verified in the application of front terminal of high speed optical transport system.

A Family of Protograph-Based LDPC for Space Communication

XIA Guojiang, SUN Hui-xian, XIONG Wei-ming

2009, 30(11):  1546-1552.  doi:10.3969/j.issn.1000-1093.2009.11.026

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Taking aim at the higher complexity of decoding AR4JA codes and the characters of space communication, a new protograph based rate compatible family of LDPC codes were constructed. The difference between the decoding thresholds of these codes and their capacity limits is witnin about 0.5 dB. These codes also have minimum distance growing linearly witli code length, which is of advantage for low error floor performance. In addition, a common decoder can be used for decoding all rates with the same protograph. In the aspects of theory and computer simulation, protograph based LDPC was compared with AR4JA protograph based LDPC which was proposed for CCSDS by NASA JPL. The compared result shows that the performances of both are of little difference, but the latter’s computa?tional complexity is higher than the former.

Research on Survivability Model of Underwater Monitoring System

ZHOU Rui, QIAO Chun-jie, WANG Yue-ke

2009, 30(11):  1553-1557.  doi:10.3969/j.issn.1000-1093.2009.11.027

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Being faced with complicated marine environment, the survivability of an underwater moni?toring system is sharp focused is the design stage. The survivability design provides guarantee for mak?ing services of the system meet user’s requirements when the system encounters attacks, failures, and accidents et al. According to system characteristic and probability distribution of events in some envi?ronment, survivability of the system was quantified by mathematical expectation of services perfor?mance of the system. The changing process of influence of events on survivability performance was simulated by state transition matrix based on survivability models of events and state of the system. The simulated results by an example show that the established models are correct and have important effects for designing the system and evaluating survivability of the system.

The Confidence Intervals for the Scale Parameter of the Birnbaum-Saunders Fatigue Life Distribution

SUN Zhu-Iing

2009, 30(11):  1558-1561.  doi:10.3969/j.issn.1000-1093.2009.11.028

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No simple and effective frequentest approach is now available about interval estimations of the parameters of Birnbaum-Saunders fatigue life distribution, the common distribution in reliability analysis. A question of interval estimation of the parameter of this distribution was discussed. A new pivotal variable to construct the classical confidence intervals for the scale parameter was given. And precision confidence intervals for the scale parameter of this distribution with a simple form were also obtained. The result makes an important progress for the parameter estimation of this distribution.

Research on Multi-UCAV Cooperative Route Planning Based on Coevolutionary Multi-Ant-Colony Algorithm

SU Fei, PENG Hui, SHEN Lin-cheng

2009, 30(11):  1562-1568.  doi:10.3969/j.issn.1000-1093.2009.11.029

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Cooperative route planning is one of the key technologies increasing the efficiency of multi unmanned combat aerial vehicles (UCAV) to perform cooperative missions. The space, precedence and time window constraints in multi-UCAV cooperative route planning were analyzed, and the crite?ria of cooperative route estimation based on cooperative coefficient were presented; The cooperative route planning algorithm based on the coevolutionary multi-ant-colony algorithm was designed and im-plemented by the coevolutionary strategy among multi- ant- colony and. the improved state transition rule and pheromone updating mechanism. The simulated results show that the proposed method can solve the cooperative constraints efficiently, and is effective for the multi-UCAV cooperative route planning problem.