水下无人系统学报

Strategy and Key Technologies of UUV Parking on the Seabed

SONG Bao-wei, ZHU Xin-yao, CAO Yong-hui, LIANG Qing-wei

2010, 18(6): 401-405. doi: 10.11993/j.issn.1673-1948.2010.06.001

[Abstract](1926) [PDF 572KB](1218)

Abstract:
Unmanned underwater vehicle（UUV）achieves wide applications, however it can not meet the requirement of long time reconnaissance and exploration. This paper analyzes the development, principle, key configuration and main parts of UUV that can park on the seabed, and presents two types of UUVs parking on the seabed-hydraulic support type and anchoring type. Their main composition, working principle and working process are simply described. Moreover, this paper discusses the key technologies of parking on the seabed for UUVs according to the parking strategies of these two types of UUVs.

Design of Visual Federate in Torpedo Virtual Test System Based on HLA

HU Jun-peng, HUANG Zhi-ping, LIU Chun-wu

2010, 18(6): 406-409. doi: 10.11993/j.issn.1673-1948.2010.06.002

[Abstract](1307) [PDF 1289KB](724)

Abstract:
Based on the real-time visual simulation software, Vega Prime and the high level architecture (HLA), the romancing thread and the data exchange thread of the virtual federate in the torpedo virtual test system is designed, and the problem of thread synchronization is solved to meet the requirement of the data visualization in the torpedo virtual test system. In view of the fact that the interface of each federate has the same characteristic, the federate interface dynamic link lib(DLL) is designed to settle the difficulty of code maintenance. A case study shows that the system displays images smoothly and realistically, meeting the real-time requirement.

Analysis of Internal Flow Field of Ventilation System for Ultra High Speed Torpedo Using CFD

WANG Ya-dong, YUAN Xu-long, ZHAHG Yu-wen

2010, 18(6): 410-413. doi: 10.11993/j.issn.1673-1948.2010.06.003

[Abstract](1748) [PDF 756KB](809)

Abstract:
In order to investigate the characteristics of ultra high speed torpedo (UHST) ventilation system and obtain solutions of mass flow rate allocation in specified proportion, we computed the flow flied with the CFD software FLUENT based on the compressible gas-water multiphase flow model. The flow field was simulated using a 2D axisymmetric mesh, and the contours of gas volume fraction, pressure, temperature and Mach number were achieved. By analyzing the characteristics of the flow field, a scheme for designing the sizes of ventilation holes was presented to realize the allocation of mass flow rate in specified proportion. The result has been applied to design a ventilation system, and the test verified the present scheme.

Analysis of Torpedo Positions Externally Hanged on UUV Based on CFD

ZHOU Jie

2010, 18(6): 414-418. doi: 10.11993/j.issn.1673-1948.2010.06.004

[Abstract](1663) [PDF 687KB](762)

Abstract:
In order to analyze the optimum positions of external torpedoes hanged on unmanned underwater vehicle (UUV), we first determined the external positions preliminarily via the underwater stability of the UUV after hanging torpedoes, and then calculated the hydrodynamic parameters of different external positions by FLUENT. According to the selected UUV, the best positions of the external torpedoes were obtained on both sides of the bottom of UUV. The dynamic motion characteristics of external positions are simulated by establishing SIMULINK spatial motion model, and the calculated results of the best positions are verified.

Reliability Estimation Method of Torpedo in Multimode Condition

ZHOU Chun-ming

2010, 18(6): 419-421. doi: 10.11993/j.issn.1673-1948.2010.06.005

[Abstract](1486) [PDF 175KB](711)

Abstract:
To accurately evaluate the reliability of a torpedo and provide evidence for test and usage, this paper presents a reliability estimation method and the lower confidence limit for torpedo in multimode condition by analyzing the multimode feature and binomial distribution of torpedo test. The fuzzy statistics theory and method are used in this study to substitute the sum of acceptable quality levels for successful test number.

Space-time Optimum Processing for Acoustic Homing System in Reverberation Background

ZHOU Jing, HAO Bao-an, CHEN Ya-lin, HU Qiao

2010, 18(6): 422-425. doi: 10.11993/j.issn.1673-1948.2010.06.006

[Abstract](1322) [PDF 595KB](731)

Abstract:
Reverberation is the main background noise of the torpedo active sonar, which limits active sonar target detection in the shallow sea. Space-time two-dimensional spectrum characteristic of receipting reverberation signal for homing system in the motion process are analyzed based on the reverberation Doppler variation at different angles of incidence. Optimum space-time processing and the evaluation method are also analyzed. The validity of this method is verified by the simulation output of the processor, the judgment criterions of space-time adaptive process technology are discussed, and the influence of the variation of array element number on the improvement factor of the optimum processor is analyzed.

Simulation of the Backscattered Signals for Laser Wake Guided Technique

ZHU Dong-hua, ZHANG Xiao-hui, XIA Min, RAO Jiong-hui, GU Jian-nong

2010, 18(6): 426-429. doi: 10.11993/j.issn.1673-1948.2010.06.007

[Abstract](1768) [PDF 397KB](750)

Abstract:
To study the mechanism of laser wake guidance, the laser backscattered signals from ship bubble wake received in the process of underwater vehicle full range detection were modeled and simulated, a ship wake data model and a laser backscattering model for wake bubble were built up, and a simulation software for the optical wake guided signals was programmed based on the models. The software could be used to simulate and obtain the laser scattering signals curves from the wakes of five typical U.S. naval warships with several simulation parameters by using the Monte Carlo simulation kernel and the typical surface ship wakes data. Simulation results exhibit the characteristics of laser backscattered signals under different conditions, and provide a criterion for the laser wake guided technique.

Waveform Reconstruction of Ship Radiated Noise

LUO Jian, CHENG Yue-wei, XIANG Jing-lin

2010, 18(6): 430-434. doi: 10.11993/j.issn.1673-1948.2010.06.008

[Abstract](1325) [PDF 420KB](663)

Abstract:
To realize physical simulation of ship radiated noise for physically detecting and assessing weapon and sonar prototype, an algorithm of generating a random time sequence with both specified amplitude probability distribution and desired spectral feature is obtained based on the linear system theory. By means of this algorithm, successive output of simulating ship radiated noise is achieved, and the noise spectral distortion caused by transducer system response can be corrected easily. The equivalent electrical performances of receiving transducer are discussed to construct an acoustic-electrical simulation system over a wideband range (3 Hz～20 kHz). Making use of acoustic coupling cavity，coupled vibration liquid and anechoic tank, physical simulation experiment for target detection system (TDS) can be conducted expediently. The reconstructed ship radiated noise includes continuous power spectrum density (PSD), the lines of the PSD, the envelope spectrum, the total radiated acoustic power and the time signature of noise.

A Passive Localization Method Using Near-field MVDR Focused Beamforming

XIONG Xin, ZHANG Xin-hua, HUANG Guan, LU Hai-jie, LAN Ying

2010, 18(6): 435-439. doi: 10.11993/j.issn.1673-1948.2010.06.009

[Abstract](1778) [PDF 655KB](1156)

Abstract:
This paper systematically researches the localization performance of the minimum variance distortionless response(MVDR) focused beamforming method and the influences of localization performance caused by some parameters in detail. We analyze the model of the receiving signals of linear array in near-field environment, and deduce the localization principles of the conventional focused beamforming method and MVDR focused beamforming method. We compare the localization performances of these two methods by simulation, and the localization performance of the MVDR focused beamforming method in the case of different array element spacings and target ranges. Simulation result indicates that, compared to the conventional focused beamforming method, the MVDR focused beamforming method can improve the resolution and reduce the influence of “aliasing” with smoother background and lower side-lobe level. To obtain better location effect, target must be in near-field position.

Simulation and Design of Adjustment System for Gravity Driven Underwater Gliders

HAN Ding-bang, SHI Xiu-hua, ZHAO Li-qiang, YANG Hui-tao

2010, 18(6): 440-444. doi: 10.11993/j.issn.1673-1948.2010.06.010

[Abstract](1778) [PDF 702KB](925)

Abstract:
To study the relationship between the motion parameters and control variables of the underwater glider, overall analysis of the weight-driven underwater glider is conducted, and gravity buoyancy adjustment mechanism and gravity center adjustment mechanism are designed. Mechanical analysis of the underwater glider with a gravity adjustment device installed in its bow is also conducted to get the parameters of the underwater glider’s control system. Kinematic equations are derived on the basis of Newton-Euler method, and simulation via the software Matlab is performed. The results show that the glider’s pitch angle, attack angle and velocity increase with the increasing mass moving distance or net buoyancy, there is an extreme value of horizontal velocity when net buoyancy is fixed. Finally, the parameters of gravity adjustment mechanism and gravity buoyancy adjustment mechanism are determined for achieving maximum horizontal velocity.

Design and Simulation of Test Route for Underwater Vehicle

WU Bi, WANG Xin, WANG Hua-kui

2010, 18(6): 445-448. doi: 10.11993/j.issn.1673-1948.2010.06.011

[Abstract](1820) [PDF 156KB](769)

Abstract:
The navigation accuracy test of underwater vehicles is closely related to test route design. To design optimal test route and get real navigation accuracy, this paper simulates the navigation system to get its accuracy in linear route, open-annular route, and annular route tests, respectively. Simulation result shows that the navigation accuracy in annular route test is lower than the real value due to error counteraction, while the navigation accuracy in linear route test gets closer to the real value. This paper offers a new test route design method by using simulation for underwater vehicle test.

Stability Analysis of Networked Torpedo Control System with Uncertainties

LI Juan-li, LIU Wei-dong, ZHANG Xing-hua

2010, 18(6): 449-452. doi: 10.11993/j.issn.1673-1948.2010.06.012

[Abstract](1725) [PDF 424KB](725)

Abstract:
Stability is the most important factor for networked control system. According to the structure and character of the networked control system, a simulation framework based on TrueTime is established to describe the yaw control of torpedo. In the simulation, the influences of such uncertain factors as network time delay and data packet missing on the stability of proportional integral differential(PID)control system are analyzed. The Lyapunov stability theory and the linear matrix inequality(LMI)are used in the design of the controller to ensure the stability of the networked control system. Simulation results show that the designed controller can weaken the influences of the uncertain factors on the networked control system, and make the control system stable.

Numerical Simulation on Inner Flow Field of Gas Turbine with Partial Inlet Flow

YI Jin-bao, ZHAO Wei-bing, SHI Hai-chao

2010, 18(6): 453-457. doi: 10.11993/j.issn.1673-1948.2010.06.013

[Abstract](1547) [PDF 2127KB](560)

Abstract:
A three-dimensional, viscous, steady CFD analysis is performed for investigating gas turbine flow field with partial inlet flow, by solving RANS-Navier-Stocks equations and RNG k- turbulence model. The inner flow mathematics of turbine is studied in detail. The results show that the inner complex flow characteristics of the turbine can be predicted with the present simulation method; the inlet shock wave and flow separation occur in turbine because of the supersonic inlet flow, leading to worse load distribution on blade and turbine efficiency; strong three-dimensional vortex structures occur in the inner flow of turbine because of the partial inlet flow design and the high speed rotation of turbine; the turbine blades work under the alternating impact force, which imposes a bad effect on the blade stress distribution. This study may offer a reference for the design and engineering application of the gas turbine with partial inlet flow.

Starting Method of Sensorless Permanent Magnet Brushless DC Motor in AUV Adopting Third-harmonic Integral Method

LI Hong, WANG Chong-wu

2010, 18(6): 458-464. doi: 10.11993/j.issn.1673-1948.2010.06.014

[Abstract](1921) [PDF 507KB](723)

Abstract:
autonomous underwater vehicle (AUV); permanent-magnet brushless DC motor (PMBLDCM); third- harmonic integration method; position sensor; starting method

Analysis of Salvo Test and Evaluation for Two Torpedoes

HE Cheng-gang, TANG Shi-xuan, DENG Nan-ming

2010, 18(6): 465-469. doi: 10.11993/j.issn.1673-1948.2010.06.015

[Abstract](1422) [PDF 234KB](686)

Abstract:
There exist differences in torpedo salvo test method and evaluation standard. According to the definition of the salvo test for torpedoes and the factor that influences the performance of torpedo salvo, the requirement for evaluating the salvo performance of acoustic homing torpedo during the whole process of search, tracking and attack is proposed in this paper. Then an optimal salvo test scheme following the evaluation standards is recommended. And a new salvo test method for wake homing torpedoes is presented, (which includes at first launching single torpedo to pass through its own wakes at different angles for several times so as to check whether the wake homing torpedo can detect the torpedo wake or not, and then deciding whether the wake homing torpedoes salvo can be performed, finally conducting salvo test.

Models of Launching Opportunity and Initial Course for Mobile Acoustic Decoy Launched by Submarine

LI Chang-jun, WANG Shun-yi

2010, 18(6): 470-474. doi: 10.11993/j.issn.1673-1948.2010.06.016

[Abstract](1503) [PDF 249KB](682)

Abstract:
Launching opportunity and initial course are important factors in operational effectiveness of mobile acoustic decoy. We analyze the operational process of submarine defending acoustic homing torpedo with a mobile decoy, establish a mathematical model to calculate the valid range of launching opportunity and initial course of mobile acoustic decoy in a certain countermeasure situation. Based on initial information of torpedo alerting, optimized launching opportunity and initial course are obtained by the optimum search algorithm.

Torpedo Coordinated Attack by Two Helicopters Against Operational Countermeasures

JIAN Ming-yu, DING Hong-yan, WANG Jia-xing

2010, 18(6): 475-478. doi: 10.11993/j.issn.1673-1948.2010.06.017

[Abstract](1442) [PDF 269KB](701)

Abstract:
Considering that target submarine adopts such countermeasures as evasive maneuver and deployment of noise jammer when helicopter launches torpedoes, we analyze the organization of torpedo coordinated attack by two helicopters and the selection of aiming point which affects hit probability, establish a conversion model of coordinated attack parameter, a model of submarine evasive maneuver, and a model of noise jammer. Compared with single helicopter torpedo attack, the coordinated attack by two helicopters against operational countermeasures can effectively increase torpedo hit probability and achieve higher target detecting probability.

2010 Vol. 18, No. 6

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