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Engineering Model for Detecting Sensitivity of the Coupling Capacitance Detector 被引量:2
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作者 王伟 邓甲昊 +1 位作者 尹君 黄艳 《Journal of Beijing Institute of Technology》 EI CAS 2004年第1期54-57,共4页
The sensitivity engineering model of the coupling capacitance detector is built to provide the theoretic foundation for designing its circuits and electrodes scientifically. The sensitivity concept model of the capaci... The sensitivity engineering model of the coupling capacitance detector is built to provide the theoretic foundation for designing its circuits and electrodes scientifically. The sensitivity concept model of the capacitance proximity detector is discussed, and the detecting sensitivity of the coupling capacitance detector is analyzed theoretically. Then the sensitivity engineering model, which can reflect the main parameters relationship of the detecting circuit is set up based on the foregoing analyses. It is concluded that: ① the sensitivity is mainly correlative with some parameters including the voltage transmission factor of the demodulator, the oscillating voltage amplitude and the amplitude variation constant of the oscillator; ② the sensitivity is also influenced by the areas of electrodes and the distance between electrodes of the detector. 展开更多
关键词 proximity detector coupling capacitance detector sensitivity engineering model
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DEVELOPMENT AND MOTION ANALYSIS OF MINIATURE WHEEL-TRACK-LEGGED MOBILE ROBOT 被引量:11
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作者 DUAN Xingguang HUANG Qiang +2 位作者 XU Yan RAHMAN N ZHENG Change 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2007年第3期24-28,共5页
A miniature wheel-track-legged mobile robot to carry out military and civilian missions in both indoor and outdoor environments is presented. Firstly, the mechanical design is discussed, which consists of four wheeled... A miniature wheel-track-legged mobile robot to carry out military and civilian missions in both indoor and outdoor environments is presented. Firstly, the mechanical design is discussed, which consists of four wheeled and four independently controlled tracked arms, embedded control system and teleoperation. Then the locomotion modes of the mobile robot and motion analysis are analyzed. The mobile robot can move using wheeled, tracked and legged modes, and it has the characteristics of posture-recovering, high mobility, small size and light weight. Finally, the effectiveness of the deve-loped mobile robot is confirmed by experiments such as posture recovering when tipped over, climb-ing stairs and traversing the high step. 展开更多
关键词 Mobile robot Locomotion modes STAIR-CLIMBING Posture recovery
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Simulation on the Models of Small Scale Passive Acoustic Sensor Arrays Based on Time-Delay Estimation Method 被引量:2
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作者 李杰 李喆 陈文聪 《Journal of Beijing Institute of Technology》 EI CAS 2005年第2期162-165,共4页
The passive acoustic localization with planar sensor array is introduced. Based on a method to eliminate the influence of effective sound velocity in passive detection, a new five-sensors solid array and its localizat... The passive acoustic localization with planar sensor array is introduced. Based on a method to eliminate the influence of effective sound velocity in passive detection, a new five-sensors solid array and its localization model are put forward. The factors that influence the precision of the localization are analyzed. Considering the errors from the factors synchronously, the simulation compares the solid array with the planar array. It can be proved that the five-sensor solid array is better than the four-sensor planar array in the estimation of bearing elements. 展开更多
关键词 passive acoustic detection acoustic localization sensor array time-delay estimation
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Wind Tunnel Experimental Investigation on the Aerodynamic Characteristics of the Multifin Rockets and Missiles 被引量:1
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作者 郝璐 吴甲生 《Journal of Beijing Institute of Technology》 EI CAS 2005年第3期293-296,共4页
The transonic-supersonic wind tunnel experiment on the aerodynamics of the rockets and missiles that have four, six, eight flat or wrap-around fins is introduced. The experimental results show, while M∞〈2.0, with th... The transonic-supersonic wind tunnel experiment on the aerodynamics of the rockets and missiles that have four, six, eight flat or wrap-around fins is introduced. The experimental results show, while M∞〈2.0, with the increase of the fins'number, the derivative of lift coefficient is increasing, the pressure center is shifting backwards, and the longitudinal static stability is augmenting. On the contrary, while the Mach number exceeds a certain supersonic value, the aerodynamic effectiveness of the eight-fin missiles would be lower than that of the six-fin missiles. For the low speed short-range missiles, by adopting six, eight or ten flat fins configuration, the lift effectiveness can be greatly increased, the pressure center can be shifted backwards, the static and dynamic stability can be obviously enhanced. For the high speed long-range large rockets and missiles launched from multi-tube launcher, the configuration adopting more than six fins can not be useful for increasing the stability but would make the rolling rate instable during the flight. 展开更多
关键词 multifin wrap-around fins flat fins aerodynamic characteristics wind tunnel experiment
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Investigation and Application of Automatic Fingerprint Identification Based on Fuzzy Pattern Recognition 被引量:1
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作者 杨阳 康景利 +1 位作者 郭银景 唐富华 《Journal of Beijing Institute of Technology》 EI CAS 2004年第S1期49-53,共5页
Fingerprint image is a typical non-restraint image that has some uncertainty, which makes it difficult to perform identification using classical approach. Therefore, fuzzy pattern recognition is applied to match indiv... Fingerprint image is a typical non-restraint image that has some uncertainty, which makes it difficult to perform identification using classical approach. Therefore, fuzzy pattern recognition is applied to match individual query by searching the entire template database. The fuzzy maximum subordinate principle is used to solve shift matching. Through experimenting and analyzing, the approximate principle fuzzy method is employed by selecting fuzzy characteristics and determining the similarity function to achieve the further accuracy. Theoretical and experimental results show this approach is effective and reasonable. 展开更多
关键词 fuzzy pattern recognition fingerprint identification maximum subordinate principle approximate principle
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Self-Adaptive Matching Method of Signal and Energy Transmission 被引量:1
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作者 李杰 曲秀杰 +1 位作者 李喆 张峰 《Journal of Beijing Institute of Technology》 EI CAS 2003年第1期55-58,共4页
Aimed at the rapid message setting of the passive systems, the efficiency of energy transmission and the characteristics of signal transmission in the message setting are analyzed, which is based on the methods of the... Aimed at the rapid message setting of the passive systems, the efficiency of energy transmission and the characteristics of signal transmission in the message setting are analyzed, which is based on the methods of the circuit analysis and the electromagnetic induction technology. A self-adaptive impedance matching method of signal and energy transmission, which can set the message rapidly and effectively, is put forward. The electromagnetic induct setting system will reach the highest energy transmission efficiency when the equivalent resistance of the second loop is equal to the resistance of the first loop. The greater the ratio of the equivalent resistances is, the higher efficient the signal transmission has. Moreover, the validity of the method is verified by circuit design and tests. 展开更多
关键词 electromagnetic induction energy and signal transmission impedance matching message setting
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Analysis of Controlled Trajectory Optimization for Canard Trajectory Correction Fuze 被引量:1
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作者 郭泽荣 李世义 申强 《Journal of Beijing Institute of Technology》 EI CAS 2004年第4期410-413,共4页
The optimization method of the canard trajectory correction fuze's controlled trajectory phase is researched by using the aerodynamics of aerocraft and the optimal control theory, the trajectory parameters of the ... The optimization method of the canard trajectory correction fuze's controlled trajectory phase is researched by using the aerodynamics of aerocraft and the optimal control theory, the trajectory parameters of the controlled trajectory phase based on the least energy cost are determined. On the basis of determining the control starting point and the target point, the optimal trajectory and the variation rule of the normal overload with the least energy cost are provided, when there is no time restriction in the simulation process. The results provide a theoretical basis for the structure design of the canard mechanism. 展开更多
关键词 trajectory correction trajectory optimization FUZE OVERLOAD
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Optimum Optical Length of the Gas Cell Used for Monitoring Gas-In-Oil with FTIR 被引量:1
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作者 刘先勇 黄风雷 +1 位作者 王霞 周方洁 《Journal of Beijing Institute of Technology》 EI CAS 2003年第1期59-63,共5页
Dedicated experiments are designed to collect the infrared spectra of dissolved gas-in-oil of power transformers. Spectra of diagnostic gases are collected by 3 different laboratorial FTIR spectrometers using 3 differ... Dedicated experiments are designed to collect the infrared spectra of dissolved gas-in-oil of power transformers. Spectra of diagnostic gases are collected by 3 different laboratorial FTIR spectrometers using 3 different gas cells with various sets of equipment parameters. A formula is deduced to calculate the shortest optical length to detect a specific concentration according to measurements on gases with known concentrations near to the minimum detection limit. Collected spectra and calculated results suggested that the optimum optical length of the gas cell should be 150 mm to realize on-line monitoring of diagnostic gases within the required concentration range. At the end, an economic novel design of the gas cell is proposed based on the optimum length. 展开更多
关键词 FTIR gas cell power transformer DGA optical length dissolved gas-in-oil
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Dynamic Damage Model of Brittle Rock and Its Application 被引量:1
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作者 高文学 刘运通 +1 位作者 杨军 黄风雷 《Journal of Beijing Institute of Technology》 EI CAS 2003年第3期332-336,共5页
On the basis of shock induced experiments and the ultrasonic tests of the damaged rocks, the damage evolution relation between the attenuation coefficient of sound wave and the damage dissipated energy is described. ... On the basis of shock induced experiments and the ultrasonic tests of the damaged rocks, the damage evolution relation between the attenuation coefficient of sound wave and the damage dissipated energy is described. Based on the TCK and RDA models, a damage model which connects the shock compression and tensile damage is established. And then the damage model is implemented in LS DYNA3D dynamic nonlinear program. Numerical simulation of deep hole blasting of groove is studied by use of the damage model proposed. The rock damage evolution process and the distributing rules of stress field under the explosion load are described well fairly, which provides the theory basis for the engineering blasting design. 展开更多
关键词 brittle rock dynamic damage model numerical simulation
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Theoretical Analysis of Noise of Piston Knocking Cylinder Wall in Automotive Engines 被引量:1
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作者 肖云魁 李世义 +2 位作者 曹亚娟 杨万成 冯汉生 《Journal of Beijing Institute of Technology》 EI CAS 2005年第3期284-288,共5页
Based on the loading conditions of engine, applying difference method to solve the hydrodynamic lubrication equation of piston skirt movement, the force acting on piston skirt and the moment on wrist pin were obtained... Based on the loading conditions of engine, applying difference method to solve the hydrodynamic lubrication equation of piston skirt movement, the force acting on piston skirt and the moment on wrist pin were obtained. A computer program for simulating the piston second order motion was conducted to calculate the lateral motion of the upper part and the bottom part of piston skirts of the engine of automotive model CA1091. From the simulated result, the maximal impacting phase and the maximal impacting region of the piston were obtained. The result can be used for designing engine, diagnosing the noise of piston knocking cylinder wall and explaining many practical fault phenomena in theory. 展开更多
关键词 piston knocking cylinder wall second order motion fault diagnosis
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Interference of the Cloud to Capacitance Proximity Fuze 被引量:1
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作者 李明 崔占忠 张万君 《Journal of Beijing Institute of Technology》 EI CAS 2004年第S1期45-48,共4页
Based on the study of the characteristics of the cloud, firstly the interference mechanism of the capacitance proximity fuze passing through the cloud has been studied. Analysis shows that the medium property of the c... Based on the study of the characteristics of the cloud, firstly the interference mechanism of the capacitance proximity fuze passing through the cloud has been studied. Analysis shows that the medium property of the cloud only, has little effect on the capacitance proximity fuze. Secondly, the adherence interference of the cloud to capacitance proximity fuze has been studied for the first time in this paper. Then finite element analysis (FEA) method has been used to simulate the adherence interference of the cloud. Simulation result shows that the cloud adherence effect interferes the output of the capacitance fuze greatly. At last, experiments have been made for the study of the cloud interference. 展开更多
关键词 CLOUD capacitance fuze: interference: finite element analysis
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Synthesis of Amino Acid Derived β-Cyclodextrins Used in Chiral Separation by Capillary Electrophoresis 被引量:1
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作者 戴荣继 佟斌 +4 位作者 魏征 顾峻岭 邓玉林 李明愉 傅若农 《Journal of Beijing Institute of Technology》 EI CAS 2004年第2期206-209,共4页
Six new kinds of amino acid derived β-cyclodextrins were synthesized to improve their water solubility and chiral separation properties. They are heptakis{2,6-di-O-[3-L-(1-isopropyl carboxyl methyl amino)-2-(hydroxy)... Six new kinds of amino acid derived β-cyclodextrins were synthesized to improve their water solubility and chiral separation properties. They are heptakis{2,6-di-O-[3-L-(1-isopropyl carboxyl methyl amino)-2-(hydroxy) propyl]}-β-cyclodextrin (i.e. L-Val-β-CD), heptakis{2,6-di-O-[3-L-(1-benzyl carboxyl methyl amino)-2-hydroxy propyl]}-β-cyclodextrin (i.e. L-Phe-β-CD), heptakis{2,6-di-O-[3-(D, L-1-benzyl carboxyl methyl amino)-2-hydroxy propyl]}-β-cyclodextrin (i.e. D,L-Phe-β-CD), heptakis{2,6-di-O-[3-(L-1-hydroxymethyl carboxyl methyl amino)-2-hydroxy propyl]}-β-cyclodextrin (i.e. L-Ser-β-CD), heptakis{2,6-di-O-[3-(L-1-carboxylmethyl carboxyl methyl amino)- 2-hydroxy propyl]}-β-cyclodextrin (i.e. L-Asp-β-CD), heptakis{2,6-di-O-[3-(L-2-carboxyl tetramethylene amino)-2-hydroxy propyl]}-β-cyclodextrin (i.e. L-Pro-β-CD). Their chemical structures were certified using FTIR and ()~1H NMR. Except for L-Phe-β-CD and D,L-Phe-β-CD, that are in soluble in water, the other amino acid derived β-CDs all have good water solubility. D,L-tyrosine and promethazine were baselinely separated by L-Val-β-CD in capillary electrophoresis. 展开更多
关键词 cyclodextrin derivatives capillary electrophoresis chiral selector
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RCS Reduction of Airborne Dispenser
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作者 郝璐 吴甲生 《Journal of Beijing Institute of Technology》 EI CAS 2004年第S1期58-62,共5页
The radar cross section (RCS) of dispenser and its components is computed by graphical electromagnetic computing (GRECO) method, which bases on physical optics (PO) method. A satisfied agreement is gotten between comp... The radar cross section (RCS) of dispenser and its components is computed by graphical electromagnetic computing (GRECO) method, which bases on physical optics (PO) method. A satisfied agreement is gotten between computed and measured results outdoor. The results show that the main scattering source of the dispenser is the mirror reflecting of the body; in the most crucial nose-on region, the nose mirror reflecting plays important role; the corner reflecting is important to the fins' RCS. The corresponding measures to reduce dispenser's RCS are proposed. It is indicated that to reduce RCS, shaping should be adopts first, while aerodynamic characteristics and stealth characteristics should be considered synthetically during the design of dispenser. 展开更多
关键词 DISPENSER radar cross section (RCS) physical optics method (PO) outdoor RCS test graphical electromagnetic computing (GRECO)
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Direct Monte Carlo Method Simulation of the Synthesis of Carbon Particle Through Coagulation in the Detonation of Explosives
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作者 马峰 恽寿榕 黄风雷 《Journal of Beijing Institute of Technology》 EI CAS 2003年第3期278-281,共4页
A model is constructed and used in computing the coagulation probability of free carbon during the detonation of explosives. A direct simulation Monte Carlo (DSMC) program is constructed to simulate the coagulation of... A model is constructed and used in computing the coagulation probability of free carbon during the detonation of explosives. A direct simulation Monte Carlo (DSMC) program is constructed to simulate the coagulation of free carbon particles. The evaluation of the distribution spectrum of particles in the system is obtained. The simulation result is consistent with the experimental curve. 展开更多
关键词 Monte Carlo method DSMC ultrafine particle COAGULATION
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Research on Protection Capability of Flying-Whip Multifunctional Explosive Reactive Armor
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作者 张虎生 张宝■ +1 位作者 张庆明 刘长林 《Journal of Beijing Institute of Technology》 EI CAS 2004年第3期299-304,共6页
The experimental research on protection capability of the flying-whip multifunctional explosive reactive armor (ERA) was performed, in which the comparison experiment was made on the damage effect of the flying-whip&#... The experimental research on protection capability of the flying-whip multifunctional explosive reactive armor (ERA) was performed, in which the comparison experiment was made on the damage effect of the flying-whip's geometrical figuration, material property and driven velocity on the long-rod armor-piercing-projectile. The moving velocity of the flying-whip driven by different explosives and the pressure attenuation law of shock wave travelling in the back plate were measured respectively with the electric probe method and the manganin piezoresistive gauge technique. The following conclusions based on a great quantity of experimental data were drawn: compared with the sandwich ERA the flying-whip multifunctional ERA has very good protection function against the long-rod armor-piercing-projectile, the shaped charge warhead and the anti-armor tandem warhead. In addition, the composite plate made of the armor-steel and rubber plate can lessen the vibration and shock of the main armor caused by the explosion of the charge.. 展开更多
关键词 flying-whip explosive reactive armor armor protection detonating acceleration impact damage
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Numerical Simulations of Jet Flow Inside Launching Box and Design of Pressure Opening the Covers of Missile Launching Box
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作者 刘琦 郝继光 +1 位作者 姜毅 陈建伟 《Journal of Beijing Institute of Technology》 EI CAS 2004年第S1期54-57,共4页
Numerical simulations are presented for jet flow inside a launching box. The predictions are based on solutions of the unsteady three-dimensional Reynolds-averaged Navier-stokes equations. Since the pressure opening t... Numerical simulations are presented for jet flow inside a launching box. The predictions are based on solutions of the unsteady three-dimensional Reynolds-averaged Navier-stokes equations. Since the pressure opening the forward cover is given, the pressure opening the backward cover is designed by analyzing the flow field inside the launching box. The κ -ε turbulent model is presented and the structured meshes are used through the whole computational field. 展开更多
关键词 launching box the pressure opening the covers jet flow
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Building and Analysis of Computer Aided Fuze Fault Tree
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作者 王亚斌 刘明杰 谭惠民 《Journal of Beijing Institute of Technology》 EI CAS 2004年第4期398-401,共4页
A common software to analyze fuze fault tree is developed to simplify the trivialness in generating the fuze fault tree and reduce the manual calculation work. The overall structure, function and implementation of the... A common software to analyze fuze fault tree is developed to simplify the trivialness in generating the fuze fault tree and reduce the manual calculation work. The overall structure, function and implementation of the system are introduced. The software based on Windows platform is used to generate the fuze fault tree in graphics mode. A quantitative analysis of fuze fault tree can be obtained by the method of minimum cut sets. A calculation example is used to verify the function of the software. Consequently, the expected requirements of this software system are achieved to a certain level. 展开更多
关键词 fuzes fault tree analysis PROGRAM
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Study of Piezoresistive Micro Electro-Mechanical Accelerometer Design Platform
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作者 张菁华 石庚辰 《Journal of Beijing Institute of Technology》 EI CAS 2005年第3期289-292,共4页
According to the inland micro electro-mechanical system (MEMS) process technique level, a design platform of piezoresistive micro electro-mechanical accelerometer is given. This platform is much more adaptable to th... According to the inland micro electro-mechanical system (MEMS) process technique level, a design platform of piezoresistive micro electro-mechanical accelerometer is given. This platform is much more adaptable to the inland designer compared with the current MEMS CAD software. The design flow is presented in detail, and the key techique in the platform is analyzed amply. The structure design methodology is exemplified in the design of a piezoresistive accelerometer, and the accelerometer is the optimized structure for the given performance requirements. The accelerometer is now being manufactured. 展开更多
关键词 micro electro-mechanical system SENSOR computer aided design
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Component-Based Software Trustworthiness Fuzzy Analytic Hierarchy Process Model
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作者 石剑飞 闫怀志 +1 位作者 秦玮 王文同 《Journal of Beijing Institute of Technology》 EI CAS 2010年第2期170-176,共7页
For a more accurate and comprehensive assessment of the trustworthiness of component-based soft- ware system, the fuzzy analytic hierarchy process is introduced to establish the analysis model. Combine qualitative and... For a more accurate and comprehensive assessment of the trustworthiness of component-based soft- ware system, the fuzzy analytic hierarchy process is introduced to establish the analysis model. Combine qualitative and quantitative analyses, the impacts to overall trustworthiness by the different types of components are distinguished. Considering the coupling relationship between components, dividing the system into several layers from target layer to scheme layer, evaluating the scheme advantages disadvantages by group decision-making, the trustworthiness of a typical J2EE structured component-based software is assessed. The trustworthiness asses model of the software components provides an effective methods of operation. 展开更多
关键词 component-based software trustworthiness analysis fuzzy analytic hierarchy process J2EE structure
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Design of Robust-Adaptive Controller of Extended Range Guided Munition
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作者 王金柱 刘藻珍 《Journal of Beijing Institute of Technology》 EI CAS 2004年第S1期63-67,共5页
Extended range guided munition (ERGM) is a complicated multi-input and multi-output control system. It is very difficult for general control method to meet both the designing stability and its dynamical performance, f... Extended range guided munition (ERGM) is a complicated multi-input and multi-output control system. It is very difficult for general control method to meet both the designing stability and its dynamical performance, for the parameters being uncertain in the ERGM model. Adaptive controller and robust tracking controllers are presented respectively in this paper. These two approaches are synthesized in order to design an improved and applied performance of ERGM controller. Computer simulation technology is used to validate it, and the result shows the design is reasonable and applied. 展开更多
关键词 adaptive control robust control: robust tracking controller
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