Table of Content

31 August 2011, Volume 32 Issue 8

Previous Issue    Next Issue

Paper

Analysis and Effect of Interval Time between Two Injections of Piezoelectric Fuel Injector

WANG Jun， ZHANG You-tong， XIONG Qing-hui， DING Xiao-liang

2011, 32(8):  913-917.  doi:10.3969/j.issn.1000-1093.2011.08.001

Asbtract ( )   PDF (1012KB) ( )  

References | Related Articles | Metrics

In order to meet the requirement of main and pilot injections in an electronically controlled diesel engine, the dwell time between two injections of piezoelectric injector was analyzed. The structure and work principle of piezoelectric injector were briefly described. The effect factors of dwell time were analyzed, such as hydraulic delay time and electric response time, and the determining rule of interval time of main injection and pre-injection was presented. The experimental data was used to verify the effect of interval time between two injections, and measure the real minimal interval time between two injections. The effects of the injection pressure in high pressure line and the interval time between two injections on the fuel injection quantity were analyzed.

Bending Fatigue Analysis of Cast Iron Crankshafts in Consideration of Fillet Rolling Effects

BAO Ke, LIAO Ri-dong, ZUO Zheng-xing

2011, 32(8):  918-925.  doi:10.3969/j.issn.1000-1093.2011.08.002

Asbtract ( )   PDF (2127KB) ( )  

References | Related Articles | Metrics

As fillet rolling hardening technique has been widely used to enhance the bending fatigue strength of cast iron crankshaft, the residual stress due to fillet rolling must be considered in fatigue analysis. For a fillet-rolled cast iron crankshaft, a three dimensional roller-multidiameter shaft contact finite element model was established, and both bodies were flexible. The roller were used to simulate the rolling process by pressing in the roller, applying a relative revolution and unloading, and then the residual stresses induced by fillet rolling were obtained. After that, the bending stresses and strains near fillet by the action of bending moment in the fatigue test were computed by a finite element static analysis of the crankshaft section. In order to describe the properties of cast iron, the material model that has the different behaviors in tension and compression were used the rolling and bending calculation. The monotonic tension and compression stress-strain curves were chosen in rolling analysis, but the cyclic curves were used in bending computation. Finally the life of critical position near fillet region was got by the local stress/strain fatigue analysis method, in which the amplitude of strain was used as a basic parameter and the residual stress caused by fillet rolling was treated as a mean stress. The results agree with the bending fatigue test results of crankshaft sections well.

The Optimal Current Phase Angle in IPM Motor in Consideration of Cross-coupling Effect

LUO Hong-hao, WANG Fu-xing

2011, 32(8):  926-930.  doi:10.3969/j.issn.1000-1093.2011.08.003

Asbtract ( )   PDF (941KB) ( )  

References | Related Articles | Metrics

The saturation and cross-coupling effects in interior permanent magnet (IPM) motors have great impact on the motor performance. To take both effects into account, a method of fitting the maximum torque per ampere (MTPA) curve by BP neural network was presented. It can be derived from the dynamic equations of IPM motors that the dynamic torque and the steady-state torque are influenced by the cross-coupling effect. However, only the variations of direct- and quadrature-axis self-inductances are normally considered in the traditional analytic methods. A BP neural network was constructed to map the nonlinearity between the current amplitude and the optimal phase angle of current. The computational and simulation results show that the errors between the analytic computational result and the result calculated by finite element method (FEA) increase with the current amplitude, while the maximum error between the fitting result and the result calculated by FEA is less than 1 degree.

Simulation Research on Control Strategy of Electromechanic Clutch During Vehicle Starting

HE Jun， JIN Hui， CHEN Hui-yan

2011, 32(8):  931-938.  doi:10.3969/j.issn.1000-1093.2011.08.004

Asbtract ( )   PDF (1453KB) ( )  

References | Related Articles | Metrics

The DC-motor-driven AMT clutch actuator was developed for an off-road vehicle. Engine model, clutch model and driveline model were built. Through analysis of the jerk and the friction work, an intelligent control strategy based on fuzzy control and fuzzy PID was proposed and its simulation model was built in slow clutch engagement stage during vehicle starting. Through simulation analysis of clutch engagement process during vehicle starting in Matlab/Simulink, results show that this control strategy has good self-adaptability for different driver’s intentions and nonlinear change of clutch load.

Sensitivity Analysis of Forced Torsional Vibration on Vehicle Powertrain

LIU Hui, CAI Zhong-chang, CAO Hua-xia, XIANG Chang-le

2011, 32(8):  939-944.  doi:10.3969/j.issn.1000-1093.2011.08.005

Asbtract ( )   PDF (1001KB) ( )  

References | Related Articles | Metrics

Based on the lumped parameter model of forced torsional vibration of powertrain, the sensitivity formulations of the torsional vibration angualr displacement of lumped masses and additional torsional vibration stress of shafts to stiffness were derived by the direct differentiation method. The sensitivity analysis of forced torsional vibration response was extended. With the powertrain of a heavy vehicle as a real example, the characteristics of sensitivities of vibration response on powertrain were calculated and analyzed. The feasibility of this method was validated. It provides the theoretical foundation for dynamic modification and optimization design of powertrain.

A Method for Recognizing Cylinder Cutout of Armored Vehicle Engine Based on Speed Complexity Analysis

QIAO Xin-yong, LIU Chun-hua, XIE Xiao-yang, ZHANG Xiao-ming

2011, 32(8):  945-949.  doi:10.3969/j.issn.1000-1093.2011.08.006

Asbtract ( )   PDF (1340KB) ( )  

References | Related Articles | Metrics

In order to get the speed characteristic of engine in misfiring condition, a measuring method for instantaneous speed of engine is researched. The tests are taken on an armored vehicle to simulate the misfire faults in the way of cutting off the fuel, and the instantaneous speed signals are measured in the conditions of normal work, incomplete combustion and misfire. In order to clear the signal noise, the original speed signal is translated into “0-1” series. Fourier analysis is done to show the irregular change of engine speed when engine cylinder is cut out. Furthermore the complexity of the speed signal is analyzed, and K［,C］ complexity is extracted. The result shows that engine cylinder cut out can be recognized by analyzing the complexity of speed.

Modeling of Electro-hydraulic Position Servo Systems of Pump-Controlled Cylinder

GAO Qiang，JIN Yong，WANG Li，HOU Yuan-long，JI Li-jun

2011, 32(8):  950-956.  doi:10.3969/j.issn.1000-1093.2011.08.007

Asbtract ( )   PDF (1019KB) ( )  

References | Related Articles | Metrics

An exact mathematic model is difficult to establish for the electro-hydraulic position servo systems of pump-controlled cylinder because of its nonlinearity and time variability. The mechanism modeling and intelligent modeling techniques were proposed to order to solve the problem. The simulation results show that the mechanism modeling technique has poor generalization and low modeling accuracy, otherwise, the fuzzy modeling and BP neural-network modeling technique can fit the nonlinearity and time-variability of the system. BP neural network modeling based on genetic algorithm offers a better solution to the local minimum in BP neural network, so the neural network modeling based on genetic algorithm has better generalization and high modeling accuracy.

Study of Anti-Swing Control of Ship-Borne Vertical Loader Machine

QU Jun， MA Da-wei， LIU Wei

2011, 32(8):  957-962.  doi:10.3969/j.issn.1000-1093.2011.08.008

Asbtract ( )   PDF (973KB) ( )  

References | Related Articles | Metrics

Ahierarchical sliding-mode control method was proposed for anti-swing control of ship-borne vertical loader machine, and Lyapunov stability criterion was used to prove its stablilty. To avoid the chattering problem due to hierarchical sliding-mode control, a fuzzy controller system was designed to adjust the parameters of sliding mode.The simulation results show that this hierarchical fuzzy sliding-mode controller had a good dynamic performance,and can meet the requirement of anti-swing control and guarantee the system stability.

Finite Element Simulation and Process Analysis of Projectile Entering into Barrel

FAN Li-xia， HE Xiang-yue

2011, 32(8):  963-969.  doi:10.3969/j.issn.1000-1093.2011.08.009

Asbtract ( )   PDF (2076KB) ( )  

References | Related Articles | Metrics

For the contact problem of projectile entering into a barrel which is difficult to solve through observation and experiment, the finite element model of projectile and barrel was established to investigate the entering process with large deformation and full friction. The dynamic explicit algorithm and Arbitrary Lagrange-Eluerian (ALE) adaptive meshing technology were used to numerically simulate the entering process of lead core projectile. The formation of indentation on rifle and the material flow in projectile were revealed, and the deformation of bullet shell and lead core were analyzed before and after the projectile enters into the barrel, and the residual stress on the projectile was investigated. The results can provide the theoretical references to improve the firing accuracy.

High Precision Echo Flight Time Measurement Method and Its Implementation

ZHANG Jin, WANG Bo-xiong, CUI Yuan-yuan, LIU Jian-nan, ZHANG Li-xin

2011, 32(8):  970-974.  doi:10.3969/j.issn.1000-1093.2011.08.010

Asbtract ( )   PDF (1119KB) ( )  

References | Related Articles | Metrics

A new high-precision echo flight time of measuring algorithm was presented by analyzing the advantages and disadvantages of high-precision digital time interval measuring algorithms, which combines the pulse counting method with the phase delay interpolation. The pulse counting method is used to ensure a large dynamic measuring range, and the double-edge triggering counter is designed to improve the accuracy and reduce the counting quantization error. The phase delay interpolation is used to reduce the quantization error of pulse counting for further improving the time measurement resolution. A n-fold phase delay interpolation was performed to raise the time measurement resolution to 1/2n of the quantized error. Test data show that the echo flight time measurement system with this algorithm as its core and implemented on Xilinx FPGA has a shorter conversion time, and a measured error is less than 55 ps.

Application of Concrete with Phase-Change Materials in Pavement Infrared Camouflage

JIA Qi，LV Xu-liang，RONG Xian-hui，HE Chao，TANG Xue-feng

2011, 32(8):  975-980.  doi:10.3969/j.issn.1000-1093.2011.08.011

Asbtract ( )   PDF (1465KB) ( )  

References | Related Articles | Metrics

As a result of peculiar thermal infrared exposing signature of concrete, effective infrared camouflage methods for pavement have not been reported yet. Several methods were used to modify the thermal characteristics of concrete, which include mixing high heat-transfer material, adding microencapsulated phase change material(PCMs) and spraying high reflective coating. The obtained product is called phase-changing concrete. A one-dimensional thermo-physical model was used to investigate the thermal characteristics of the phase-changing concrete. The optimized volume fractions of high heat-transfer materials and PCMs were obtained based on the model. Experiment investigations are also carried out, which proved that the added PCMs can effectively descend the temperature of concrete pavement and the thermal image is also disrupted significantly. The time-temperate curve of phase-changing concrete is consistent with that of surrounding background vegetation.

Adaptive Integral Backstepping Control for Vertical Pitch Motion of Underwater Gliders

CHEN Yu-hang, YAN Wei-sheng, GAO Jian, DU Liang

2011, 32(8):  981-985.  doi:10.3969/j.issn.1000-1093.2011.08.012

Asbtract ( )   PDF (939KB) ( )  

References | Related Articles | Metrics

The pitch motion tracking and controlling problems of buoyancy-driven underwater glider were studied for the uncertainty of its dynamic model and parameters. The relationship between pitch angle and moving mass displacement was determined, a adaptive nonlinear tracking controller based on Lyapunov theory and backstepping was designed, the uncertainty of model parameters was solved using an adaptive mechanism, and the integral items were synthesized to reduce steady error. And then The backstepping method was used to design a moving mass servo controller by taking the moving mass displacement as a reference input. The controller can enable the underwater glider to tack a pitch angle reference command globally and asymptotically. The stability and error convergence of the system were proved based on Lyapunov theory. Simulation results show that the method can verify the global asymptotical stability of the controller and its adaptability to the uncertain parameters of model.

Research on High-Resolution Direction-of-Arrival Estimation Based on An Acoustic Vector-hydrophone

LIANG Guo-long， ZHANG Kai， FU Jin， ZHANG Yao， LI Li

2011, 32(8):  986-990.  doi:10.3969/j.issn.1000-1093.2011.08.013

Asbtract ( )   PDF (1474KB) ( )  

References | Related Articles | Metrics

In order to increase the resolving power for only using a single acoustic vector-sensor, the MUSIC algorithm is applied to the DOA (direction of arrival) estimation.Taking into account the characteristic of single coustic vector-sensor, the high-resolution DOA estimation based on subspace decomposing theory is realized. According to the problem apprearing in the application, the improved algorithm is advanced. Simulation indicates that the result using the algorithm achieves the high-resolution DOA estimation whether narrowband or wideband signal with theirs information unknown and obtains the gradually agonic estimation without bias when the SNR (signal-to-noise ratio) is high. The result of processing data testifies to the validity of improved algorithm.

Research on the Outlet Cavity Features during the Launch of Submarine Launched Missile

WANG Ya-dong，YUAN Xu-long，QIN Dong-sheng

2011, 32(8):  991-995.  doi:10.3969/j.issn.1000-1093.2011.08.014

Asbtract ( )   PDF (1063KB) ( )  

References | Related Articles | Metrics

Submarine launched missiles are usually ejected by a gas-steam ejection system. In the separating process of missile tail and canister outlet, there is a strong interaction between water and gas, and a cavity is formed in front of the canister outlet. The cavity’s development affects the launch platform. CFD software FLUENT was used to simulate the process of cavity development and its effect on the launch platform. The pressure pulsations on the different places of the submarine surface and their effect on launch deep were affected by depth were investigated. The simulated result shows that the simulated data is agreement with the experiment data, and the investigation method is valid.

Damp Network Design of Horizontal Loop in Strapdown Inertial Navigation System

ZHA Feng， XU Jiang-ning, QIN Fang-jun, JI Bing

2011, 32(8):  996-1001.  doi:10.3969/j.issn.1000-1093.2011.08.015

Asbtract ( )   PDF (1340KB) ( )  

References | Related Articles | Metrics

The damp network design for strapdown inertial navigation system (SINS) was studied according to the control model and error characteristic of SINS horizontal loop. The stability and frequency characteristic of the system was analyzed on the basis of the control model. As the logarithmic magnitude curve of the horizontal loop model on different frequency bands reflected different performance of the system, a design method based on the expected curve was proposed. In the method, the time-domain performance indexes were transformed to frequency parameters, by which the expected logarithmic magnitude curve was plotted. Finally the damp network parameters were obtained. Digital simulation and test on sea for SINS were completed. In the simulation the Schuler oscillation in attitude error was damped to zero and the position error was increased to 1.5 nmile/24 h from 4 nmile/24 h, and in the test on sea the attitude accuracy improved by 1 order and the position accuracy improved by 1 time when the damp network was cascaded into the SINS. Compared with the network designed by the tentative method, this damp network has the same steady-state performances and less overshoot and settling time.

Cooperative Navigation for Multiple Autonamous Underwater Vehicles Based on Relative Displacement Measurementwith a Single Leader

LI Wen-bai, LIU Ming-yong, ZHANG Li-chuan, LIU Fu-qiang

2011, 32(8):  1002-1007.  doi:10.3969/j.issn.1000-1093.2011.08.016

Asbtract ( )   PDF (994KB) ( )  

References | Related Articles | Metrics

To meet the precision and real time performance of single leader cooperative navigation system for autonomous underwater vehicles (AUV), a novel navigation method based on relative displacement measurements is presented. By analyzing localization principle and kinematic model of the navigation system, the location estimation of the follower vehicle can be calculated by means of an extended Kalman filter (EKF) via combining dead-reckoning information and the geometric relation of relative position between the leader and follower vehicles. Compared with the existing research, simulation results show that this algorithm has a high positioning accuracy and improves the real time of the positioning calculation.

Finite Element Analysis and Control of Clamping Deformation Mechanism of Thin-wall Shell Workpiece

WANG Jun，GENG Shi-min，ZHANG Liao-yuan，LV Yu-shan

2011, 32(8):  1008-1013.  doi:10.3969/j.issn.1000-1093.2011.08.017

Asbtract ( )   PDF (1634KB) ( )  

References | Related Articles | Metrics

The thin-wall shell workpiece with insufficient rigidity is liable to deform during the machining process, and the requirement of its planeness is very strict. The paper took a typical aeronautical aluminum-alloy for example. The finite element models were established to simulate the effect of locating points, clamping sequence and loading mode on the deformation of thin-wall shell part by the action of intensive load and even load. The result shows that the clamping forces are preferably applied step by step so that the deformation of thin-wall shell part can be effectively controlled and the planeness is further improved. In the same clamping sequence and loading mode, the uniform load is better than the concentrated load. The thickness of pad was optimized for uniform loading.

Research Notes

The Analysis and Control of Low Speed of All-Electric Tank Gun Control System

ZHU Zhi-kun, MA Xiao-jun, LI Chang-bing, LI Nian-yu

2011, 32(8):  1014-1018.  doi:10.3969/j.issn.1000-1093.2011.08.018

Asbtract ( )   PDF (1300KB) ( )  

References | Related Articles | Metrics

For the nonlinear friction moment existed in all-electric tank gun control system, the factors affecting the low speed characteristic were analyzed using the piece wise linearity and state variable methods. Based on the analyzed results, a load observer was designed to observe and calculate the load change of the system. The observed values were sent to the current controller to compensate the effect of load change on the system. The simulation and experimental results show that the load observer can be used to reduce a ‘crawl’ phenomenon and improve the low speed performance of system. A feasible project was provided for the improvement of the low speed performance of all-electric tank gun control system.

Experiment Research of Sliding Mode Variable Structure Control for GYRO Stabilized Platform

YAO Zhao , LIU Jie , LI Yun-gong， YI Ying-gang， GAO Fei

2011, 32(8):  1019-1024.  doi:10.3969/j.issn.1000-1093.2011.08.019

Asbtract ( )   PDF (938KB) ( )  

References | Related Articles | Metrics

In view of the requirements of isolating disturbances and stabilizing optical axis of high-precision gyro stabilized platform, a double-axis stabilized platform system centering on the flexible gyro was designed. The gyro stabilized platform’s structure were introduced and it’s error sources was analyzed. In order to eliminate the steady-state angle error which occurs in rate gyro feedback and traditional PID control scheme, a sliding mode variable structure control scheme is presented. The results show that the gyro stabilized platform accuracy can improve 50% above after using sliding mode variable structure control. 〓〓〓

The Design and Analysis of Energy Accumulator Weapon Launching System

CHENG Guang-tao, ZHANG Zhen-shang₂, HU Kun₃, KONG Yan-feng₂

2011, 32(8):  1025-1029.  doi:10.3969/j.issn.1000-1093.2011.08.020

Asbtract ( )   PDF (933KB) ( )  

References | Related Articles | Metrics

Based on aeroelastics theory, a design of energy accumulator underwater weapon launching system for submarine is posed in order to reduce the injection noise when the weapon is launching. High pressure gas is the medium of accumulating energy, which is easy realizable in engineering. According to characters of balanceable lunching system, the mathematical modal of accumulator launching system is built, and the simulation is conducted under Matlab programming environment. The simulated results indicate that the improving launching system is realizable to launching torpedo, and the parameter of launching time，and velocity of torpedo leaving the tube correspond with the requirement of regular launching weapons. The design of the launching system reduce the pneumatic noise and eliminate the pressurization of submarine cabin, which is meaningful to the design of launching system and the improvement of reciprocating engine launching system.

FRFT-based Joint Range and Radial Velocity Estimation of Underwater Target

MA Yan, LUO Mei-ling

2011, 32(8):  1030-1035.  doi:10.3969/j.issn.1000-1093.2011.08.021

Asbtract ( )   PDF (967KB) ( )  

References | Related Articles | Metrics

A joint range/radial velocity estimation method based on Fractional Fourier Transform (FRFT) of underwater target was developed for active SONAR/RADAR. The FRFT of linear frequency modulated signal was given, and the relationship between the real signal parameter and the generalized parameter of discrete computation was shown. During discrete computation, the scaling was involved. And further, the FRFT of pulse signal was derived. The joint estimated radial velocity and range were proposed and derived, which are closely related with the location of maximum FRFT spectrum of echo. The simulation data and the measured data of water tank were used to demonstrate that the new approach can use one pulse (positive or negative LFM) simultaneously to estimate target range and radial velocity . At last, the sensitivity of estimated parameters was discussed.

Research on Estimation Method of MTBF for Zero-Failure Data in Reliability Time Truncated Qualification Test

GUO Rong-hua, WU Yu-sheng, CHEN Qing-rong

2011, 32(8):  1036-1040.  doi:10.3969/j.issn.1000-1093.2011.08.022

Asbtract ( )   PDF (937KB) ( )  

References | Related Articles | Metrics

With the advancement of design and manufacturing technology of the weapons and equipment, the probability of zero-failure is increased in the reliability time truncated qualification test. Many Statisticians have addressed such an issue, however, these methods are hardly applied because they focus on the mathematical derivation and the theoretical demonstration on zero-failure. A new method presented in this paper was used to derive a proof value of MTBF (mean-time-between-failures) from the Principle of Little-Probability according to the project of time truncated qualification test in GJB899 . The method is easily operated and practicable, and can theoretically calculate the point estimation and the confidence intervals of MTBF. In addition, the application background of the method and project was described in detail. The evaluation method can calculate the estimation value of MTBF for GJB899.