水下无人系统学报

R & D Status Quo and Perspective of Lightweight Supercavitating Torpedo in Germany

LI Ning, YANG Biao

2008, 16(2): 001-4. doi: 10.11993/j.issn.1673-1948.2008.02.001

[Abstract](2650) [PDF 772KB](1139)

Abstract:
An experimental supercavitating torpedo in Germany has achieved progress in speed and agility. The inertial guided supercavitating torpedo has successfully run at a velocity well over 200 kn. The torpedo is canard controlled. A cascaded roll-pitch control system incorporated directly in the nose of the torpedo enables very high turning rate. The internal subsystems like inertial navigation, autopilot-electronics, mechanisms and sonar components are designed to withstand high gravity environment and high jerks. Due to its high speed and the applied rocket propulsion technology,the torpedo can be well applied to short range underwater defence, High speed, fast reaction and high maneuverability support short range applications to surface ships and submarines.

Discussion on Concept and Key Technologies of Network-Torpedo

GAN Hua-dong, JI Bang-jie, ZHOU De-shan, YUN Xiao-hui

2008, 16(2): 005-8. doi: 10.11993/j.issn.1673-1948.2008.02.002

[Abstract](2077) [PDF 500KB](692)

Abstract:
Network gets more and more important in modern war. We point out that underwater operational concept on single platform is facing survival crisis based on the analysis of the concept and characteristic of network centric warfare(NCW), and present a concept of network-torpedo, its special mission and key technologies. The network-torpedo can realize real time identification, pursuit and attack on target with the information obtained effectively from battlefield at any time. We put emphasis on the functions and principles of several key technologies, including acoustic communication system, satellite navigation location system and power system. Finally, we propose some applied ideas for the network-torpedo.

Simulation of Two-dimensional Rigid Elliptic Head Structure Water Entry at High Speed

ZHENG Jin-wei, ZONG Zhi

2008, 16(2): 009-12. doi: 10.11993/j.issn.1673-1948.2008.02.003

[Abstract](2176) [PDF 422KB](675)

Abstract:
When a two-dimensional rigid elliptic head structure enters water at high speed, it endures tremendous impact arising from free water surface. It is very difficult to calculate the impact load by using normal dynamic method because of the nonlinearity of fluid-structure interface and the severe fluctuation of free water surface in the process of water entry. This paper simulates water entry of a structure with elliptic head by using the arbitrary Lagrangian-Eulerian(ALE) algorithm of ANSYS/LS-DYNA software. Simulation results show that the peaks in pressure curves increase with velocity of water entry, and there is a exponential relation between maximum acceleration and water entry velocity as this structure enters water at a specific angle. The maximum pressure appears when the angle is 35.

A Fast Initial Alignment Filtering Method of Velocity and Attitude Matching on Dynamic Base for Underwater Vehicle

LI Jun, ZHAO Hao, ZHAO Tao

2008, 16(2): 013-16. doi: 10.11993/j.issn.1673-1948.2008.02.004

[Abstract](2286) [PDF 421KB](764)

Abstract:
The alignment of underwater vehicle on dynamic base is studied, and an error model of strapdown inertial navigation system(SINS) is established. The underwater vehicle runs straightly and acceleratively in waves and winds during the process of alignment. Meanwhile the information of velocity and attitude from global positioning system(GPS) is used to help implement alignment, so the observation equations can be obtained. An alignment method based on quaternion attitude updating with the matching of velocity and attitude is proposed to estimate three initial misalignment angles. Consequently the misalignment angles are accurately and quickly estimated. Especially the method reduces the time for estimating azimuth error, and improves the accuracy of estimation. The simulation results illustrate the efficiency of the method.

Influence of Rocket Assisted Torpedo Rudder Load on Electric Steering Fin Actuator Loop Performance

HUANG Hua-hong, YIN Mei-fang, LIU Xue-chen

2008, 16(2): 017-20. doi: 10.11993/j.issn.1673-1948.2008.02.005

[Abstract](2539) [PDF 435KB](729)

Abstract:
An electric steering fin actuator loop system(ESFALS) that meets the requirements for product was designed, and a mathematical model of this system was established based on the features of hinge moment varying with time in big amplitude scope. According to the hinge moment changing law of a typical standard trajectory, the influence of load on ESFALS performance was studied. Simulation results show that steering fin working in nonlinear area has significant effect on the transition period of ESFALS and causes system divergence in the case of anti-steering.

Obstacle Avoidance for AUV in Virtual Environment

MA Wen-Jie, YAN Wei-sheng, GUI Zhi-Hui

2008, 16(2): 021-24. doi: 10.11993/j.issn.1673-1948.2008.02.006

[Abstract](2239) [PDF 490KB](713)

Abstract:
In order to simulate the process of obstacle avoidance for autonomous underwater vehicle(AUV) on horizontal plane in virtual environment, an visual simulation system of obstacle avoidance for AUV is developed on HP workstation based on the software platforms-MultiGen Creator and Vega. A simulation method of forward looking sonar(FLS) is proposed. Utilizing the collision vector function provided by Vega and the self-defined volume collision method, the function of FLS is simulated. A fuzzy inference system is designed to derive the obstacle avoidance angle based on the position relationship of AUV and obstacle. The obstacle avoidance for AUV on the horizontal plane in virtual environment is implemented. Simulation results show that this visual simulation can realistically make the simulation system approach practical circumstances, and satisfy the real time requirement of system simulation.

Space Time Adaptive Processing of Acoustic Homing Torpedo

ZHAO Shen-dong, TANG Jin-song, CAI Zhi-ming

2008, 16(2): 025-30. doi: 10.11993/j.issn.1673-1948.2008.02.007

[Abstract](2122) [PDF 763KB](875)

Abstract:
The principle of full dimension and reduced dimension space time adaptive processing (STAP) was introduced. By analyzing torpedo′s working environment and mode, and its data structure, the possibility to improve target detection performance of acoustic homing torpedo under reverberation background with STAP method was discussed, and the solutions to the key steps and the basic flow of reverberation suppression using STAP were given. The analysis shows that reverberation suppression using STAP is more difficult than clutter suppression of airborne early warning(AEW) radar, but its implementation is possible. Simulation results show that better target detection performance can be achieved by using STAP method than by conventional method. STAP method can sufficiently utilize the reverberation space time distribution characteristics of acoustic homing torpedo, so it will be a prospective method for reverberation suppression.

A Design of Multiple-mode Broadband Underwater Tonpilz Transducer

ZHANG Wen-bo, WANG Ming-zhou, HAO Bao-an

2008, 16(2): 031-33. doi: 10.11993/j.issn.1673-1948.2008.02.008

[Abstract](2201) [PDF 357KB](802)

Abstract:
With the rapid development of underwater acoustic signal processing technique, more and more information needs to be obtained from transducers, and the working frequency band of underwater acoustic transducers ought to be broader. A broadband underwater Tonpilz transducer was designed by using the coupling of transducer′s longitudinal vibration mode and the bending vibration mode of front mass to widen its frequency band. The electro-acoustic characteristics of the transducer was simulated with finite element method. The prototype transducers were made based on the results of simulations and tested. Experimental results show that the broadband characteristics of the Tonpilz transducer agree well with the simulation results. Its maximum transmitting voltage response level is 139 dB, -3dB bandwidth is beyond one octave, and low frequency is below 15kHz. Thus the designed transducer has the advantages of low frequency, broadband and high response level.

Design of Ultra-Wideband Signals Based on Chebyshev Approximation Method for Torpedo Homing System

CHEN Yong-sen, CHEN Hang, WANG Xin-hong, YAN Qing

2008, 16(2): 034-37. doi: 10.11993/j.issn.1673-1948.2008.02.009

[Abstract](1676) [PDF 413KB](677)

Abstract:
As a new developmental direction for torpedo homing system, very short impulse and ultra-wideband signal has the advantages such as more information and good anti-stealth effect. An ultra-wideband waveform design method for torpedo homing system is proposed. First, a finite impulse respond(FIR) band pass filter is designed based on Chebyshev approximation method, and then the windowed impulse response is used to adjust energy distribution of signal. Using equal spacing frequency points, this method has low calculating complexity, also it allows designers to specify signal duration, bandwidth and attenuation. Simulation result indicates that the signal has great energy attenuation outside band limit, and the energy distribute equally in band limit. Compared with narrowband signal the ultra-wideband signal imposes satisfactory suppression on reverberation.

A Method of Rotor and Stator Position Detection for Counter-rotating Permanent Magnet Brushless DC Motor

LI Hong, XU De-min, JIAO Zhei-hong, WANG Chong-wu

2008, 16(2): 038-41. doi: 10.11993/j.issn.1673-1948.2008.02.010

[Abstract](1806) [PDF 458KB](1280)

Abstract:
Counter-rotating permanent magnet Brushless DC motor (PM BLDCM) is composed of an inverter and a motor whose stator and rotor rotate in opposite direction simultaneously. Because the working state of the inverter depends on the relative position of the stator and rotor, it is very important to study an effective method to detect the relative position. This paper discusses the relations among the relative position of the stator and rotor,the working state of the motor, and the trigger logic of the inverter. A method of obtaining the position signal of the rotor and stator for counter-rotating PM BLDCM is presented by means of 12 Hall position sensors, and the logic expression about three-phase inverter state and the angle between the rotor and stator is derived. Simulation result proves this method can keep the PM BLDCM working efficiently.

Design and Implementation of Single Battery Voltage Sampling System for Wire-guided Torpedo

QI Na, YAO Shun

2008, 16(2): 042-45. doi: 10.11993/j.issn.1673-1948.2008.02.011

[Abstract](2095) [PDF 455KB](710)

Abstract:
Sampling of single battery voltage is a key technique for the charging and discharging equipment of general wire-guided torpedo. The disturbing signal will enter into the entrance of sampling to influence the stability of sampling data when strong current exists. Real-time sampling of single battery voltage during charging or discharging is implemented based on AT89S52 control core, AD629 protective circuit, and linear light coupling isolation of disturbing signal. Application results prove that the system works steady, and the sampling data are exact and credible. So the intelligence level of the charging and discharging equipment is improved with the sampling system.

Simulation of Inner Trajectory Flow Field for Pneumatic Imbalance Torpedo Launcher

SONG Bao-wei, HUANG Hai

2008, 16(2): 046-49. doi: 10.11993/j.issn.1673-1948.2008.02.012

[Abstract](1548) [PDF 435KB](682)

Abstract:
In order to directly describe the inner chamber pressure and the distribution of torpedo exit velocity, this paper builds a inner flow field model of torpedo launcher, and performs a numerical simulation based on the dynamic mesh technique of the software Fluent. Simulation result shows that the pressure distribution varies in launcher when torpedo moves in it. At beginning of launch, the pressure gradually gets lower from entrance of launcher due to throttling within the annular gap of torpedo and launcher. But with torpedo moving and the annular gap increasing, the pressure in the back section of launcher bacomes equal to the pressure at the unilateral valve entrance, and the pressure at torpedo tail is always less than the entrance pressure.

A Calculation Method of Target Motion Factors Based on Grey Relational Analysis

HUANG Wen-bing, SONG Jian-feng

2008, 16(2): 047-60. doi: 10.11993/j.issn.1673-1948.2008.02.015

[Abstract](1538) [PDF 437KB](595)

Abstract:
Aiming at the characteristic of fast attack from long distance for wire-guided torpedo,a method is presented which can quickly get the target motion factors based on grey relational analysis under an unmixed azimuth condition. According to proper division of initial target distance and velocity, as well as the board angles which are calculated via the variation of measured target bearing, different standard target classes are combined and different standard bearing sequences are obtained by simulation.Using the measured target bearing sequence as the refer sequence and the standard bearing sequences as the comparing sequences,the grey relational analysis is conducted to make sure that the target situation belongs to one of the standard classes, then the target motion factors are achieved. Simulation results show that the method can obtain the target motion factors with certain accuracy in a shorter time.

A Calculation Method of the Largest Launch Range for Wake Homing Torpedo

XIA Pei-lun

2008, 16(2): 050-52. doi: 10.11993/j.issn.1673-1948.2008.02.013

[Abstract](2177) [PDF 448KB](1053)

Abstract:
Some issues concerning the calculation of the largest launch range (LLR) for wake homing torpedo (WHT) are discussed. The LLR for WHT torpedo shows its uniqueness and complexity over straight running torpedo. The precise calculation of the LLR for WHT depends on the accurate description of the final homing pursuing trajectory of the torpedo, which is virtually impossible. An approximate calculation method is therefore presented and analyzed. The results show that the method is simple and very effective for attack decision making (ADM) of the launcher, typically the submarine. The LLR for WHT is also found not unique but changing with the anticipated impact point, which poses problems in its application to submarine ADM, therefore some solutions are proposed.

Route Planning for UUV Based on Index Function Set Order

HUANG Xin, CAI Zhi-Ming, YAO Wan-jun

2008, 16(2): 053-56. doi: 10.11993/j.issn.1673-1948.2008.02.014

[Abstract](1466) [PDF 544KB](668)

Abstract:
By analyzing the demands of route planning for unmanned underwater vehicle(UUV) carried by submarine, the high efficiency of dynamic planning algorithm and the problems caused by using a single index function in conventional dynamic planning are discussed. An improved method of index function set order is presented to enhance task adaptability. The operational opportunity and the program flow diagram are introduced. In this method,the single index function is replaced with a variable index function set. Simulation result shows that the improved method is efficient in the first step solution of route planning.

2008 Vol. 16, No. 2

Journal News> >

Download> >