Table of Content

10 June 2013, Volume 24 Issue 11

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Influence of Oil Film Thickness on Characteristics of Closed Type Hydrostatic Slide

DIAO Jian-Hua-1, 2, GAO Dian-Rong-1, 2

2013, 24(11):  1421-1424,1430. 

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In order to analyze the influence of oil film thickness on the characteristics of a hydrostatic bearing system, the initial parameters of the closed type liquid hydrostatic slide were determined. According to the force balance equation and the flow equation, mathematical models of the power loss, the static characteristics and the dynamic characteristics were established. The power loss, bearing capacity, static stiffness, natural frequency, adjusting time, dynamic stiffness can be as the indexes, the influence of the oil film thickness on the slide characteristics were analyzed quantitatively with MATLAB. The research shows that the more the oil film thickness, the larger the power loss, the longer the adjusting time, the poorer the natural frequency, the static stiffness and the dynamic stiffness, but the bearing capacity keeps constant. So the thickness of oil film can be decreased in order to decrease the power loss and to improve the static and dynamic characteristics of the slide system. The proposed research analyzes the influence of the oil film thickness on the characteristic of closed type liquid hydrostatic slide, and provides a theoretical basis for design of the oil film in practical engineering.

Research on Reliability of Domestic Drilling Mud Pump Piston-cylinder Liner Friction Pair

YU Hui-Juan, GUO Jian-Yang, SU Zi-Mei, SUN Yong-Quan, JI Jia

2013, 24(11):  1425-1430. 

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From reality manufacturing level, a method of determining life distribution based on failure mechanism was studied deeply through analyzing failure mode and failure mechanism of piston-cylinder liner friction pair, and giving the failure criteria. Lognormal distribution and Weibull distribution both can be used to fit the life of piston and cylinder liner, further more, the best life distribution was selected according to likelihood ratio test, the statistical property of the friction pair working life was discussed, Maximum likelihood estimation of the piston and cylinder liner reliability was given. Confidence lower limit of reliability life and principles of developing best maintenance program were given considering the actual drilling conditions. Validation and feasibility of these methods were proved according to oil field data.

Parametric Optimum Design and Experiment of a Cymbal Stack Piezoelectric Harvester

WEN Cheng, ZHANG Tie-Min, ZHANG Jian-Tao, CAO Fei

2013, 24(11):  1431-1436. 

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The optimum design of a cymbal stack piezoelectric harvester (CSPH) was presented using FEM parametric optimum. Firstly, the parameterized FEM model of the cymbal stack transducer was created on the basis of the initial configuration. The structural parameters were chosen as the design variables and the induced voltage on the electrode surface was taken as the objective functions. Secondly, the sub-problem approximation method was chosen as the basic tool of the structural updating. Then the structural optimization scheme of the piezoelectric harvester was carried out based on ANSYS parametric design language (APDL). Finally, a prototype CSPH was fabricated according to the optimum design results. The experimental results show that, the CSPH generated voltage amplitude is increased by 87% after optimization.

Research on Control Methods of Piezoelectric On-off Pressure-regulationType Electro-pneumatic Digital Valve

HU Wei-Xiong-1, LI Xiao-Ning-2, SHU Song-Jing-1, LIU Di-1

2013, 24(11):  1436-1441. 

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In order to improve the dynamic performance and steady-state
accuracy of a developed piezoelectric on-off pressure-regulation type electro-pneumatic digital proportional pressure valve(PDPPV for short) and decrease its pressure fluctuations,its control algorithm was researched.Based on PWM control mode,an adjusted-shift PWM algorithm(AS-PWM) was presented.Moreover,a compound control algorithm using Bang-Bang control,P with dead zone and AS-PWM was proposed to control the PDPPV.Experimental results show that this controller makes up the weaknesses of the Bang-Bang control algorithm and the compound control algorithm of  P with dead zone plus PWM and the PDPPV control performance can be improved effectively.

A Novel Effectiveness Assessment Method of Weapon System Based on Triangular Fuzzy Number Analytic Hierarchy Process

TUN Jun-1, DONG Xing-1, FANG Jiang-2, CHEN Zhi-Min-2, CENG Chang-1

2013, 24(11):  1442-1446. 

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In order to deal with the problems such as performance index in large and expert scoring uncertainty during the effectiveness assessment of weapon system, a novel effectiveness assessment method was proposed herein using the utility function and triangular fuzzy analytic hierarchy process. First of all, the hierarchical structure model and its mathematical model of weapon system effectiveness assessment were built. Furthermore, a quantitative method used in performance index layer and a computational method of system comprehensive weight was proposed respectively. Meanwhile, the whole process to assess weapon system effectiveness was described using unified modeling language(UML) sequence diagram. Finally, a case study on torpedo was implemented.

Study on Comparison and Optimization of Sheet Forming Parameters Using Kriging Interpolation and Regression Response Surface Metamodeling Techniques

QING Qi-Xiang, CHEN Zhe-Wu, LIU Jie, XIE Yu-Meng

2013, 24(11):  1447-1452,1458. 

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A sample data design was carried out by adopting Latin square experimental design method, moreover, in order to improve computing efficiency, Kriging surrogate model and polynomial regression response surface methodology were introduced into the complex system of optimization design of automotive panel sheet forming, and was employed for producing coarsen response surface. And then, the Kriging interpolation method was used for constructing the better robust surface to decide the better initial values of design variables and reduce constraints in considerable range. Finally, genetic algorithm was applied for finding the best optimization of the initial values of the design variables and the range of constraints updated. The optimization results show that is able to quantify the warpage of sheet metal forming and crack in the trends and characteristics accurately, the comparison between sequential linear programming and Kriging-based optimization method is done, and Kriging model has better predict ability than the polynomial regression model based on the classic fractional factor design, with the accuracy of the interest region and the points with larger predicted uncertainty for the accuracy and efficiency of the global approximation.

Analysis of Effect of Taper Roller Bearing Preload on Gear Whine in Manual Transmission

ZHANG Jing-1, CHEN Bing-Kui-1, TUN Chang-Hong-2, LI Chao-Yang-1, 3

2013, 24(11):  1453-1458. 

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Based on simulation analysis and experimental study,the effects of bearing preload on the whine noise in auto transmission was investigated. Firstly a fully parametric dynamic simulation model of six-speed manual transmission gearbox was set up, overall dynamic performance under different bearing preloads on countershaft was analyzed, analyses were mainly focused on the transmission error excitation, dynamic meshing force and bearing force change and dynamic response on housing. Using order tracking method, vibration acceleration and sound pressure level were investigated by experiments. The results show that: utilizing reasonable preload to increase bearing stiffness will help to control the transmission whine noise generation, and simulation and experimental results show good agreement.

All-in-one Design Optimization for Gun Manipulator

DAN Hai-Jun, JIAN Lin-Fang, XU E-Dong, CHEN Long-Miao

2013, 24(11):  1459-1463. 

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In order to overcome the lack of traditional gun optimization design of single-subject model analysis, multidisciplinary all-in-one design optimization method was employed herein. By analyzing the three disciplines and the coupling relationship between electrical controls, hydraulic and mechanical subsystems, an all-in-one analysis model for manipulator was established combining the multi-objective evolutionary algorithm. Comparing with original pre-solution, the preferable synthetically performances are obtained after optimization, and multidisciplinary all-in-one design optimization method has broad application prospects in gun design optimization.

Automated Welding for Lead Wires of Micro-motor Rotor Based on Microscopic Vision

LIU Kai, HE Gong-Han, XI Wen-Meng

2013, 24(11):  1463-1467. 

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A micro operating system which consisted of three degrees of freedom nano platform and microscopic vision was constructed, meanwhile, local calibration was made for visual space and nano platform using the movement error of characteristic objects in visual space on nano platform. Then, optimization equation was constructed and global calibration between the space of vision and the space of nano platform was carried out. When the coefficient matrix of Kalman filter equation was replaced by calibrated transformation matrix and the movements of characteristic points were controlled by the Kalman filter, the positioning precision can be improved. Besides, positioning the lead wires by high pressure airflow can overcome the problem of positioning wires because of the very soft of lead wires. The experimental results show that after the global calibration of system is done, the positioning accuracy achieves 27μm when the movements of characteristic points are controlled by vision based on position, and the precision achieves 5.4μm when the movements of characteristic points are controlled by Kalman filter. Meanwhile, the lead wires can be positioned under electrode of ERW(electric resisting welding) using the airflow positioning.

Application of EMD-ICA to Fault Diagnosis of Rolling Bearings

ZHANG Dun-Gong, LI Lin-Ji, MA Wen-Peng, LI Zhou-Yu, LIU Yu

2013, 24(11):  1468-1472. 

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Vibration signals generated by incipient faults of rolling element bearing was usually with low energy and dispersed frequency distribution, they were easily merged in strong disturbances of other vibration sources．According to this feature of rolling bearing's vibration signals, a new fault-diagnosis approach based on the combination of EMD and ICA was proposed. With the approach, single channel vibration signals were decomposed using EMD method and modal components were obtained at first, then they were restructured based on mutual correlation criterion. Therefore multi-dimensional virtual noise channels were constructed, source signals and noise signals were separated when FastICA method was adopted with multi-dimensional virtual noise channels used as input matrix of ICA. The method was applied to fault diagnosis of rolling bearings. The denoised signals were analyzed by fast Fourier transform method, then the results were compared with the fault characteristics to judge operation state of the rolling element bearings. Simulations and tests verify the feasibility of the method.

Dynamics Simulation Analysis of Column for Large-scale NC Gear Hobbing Machines

YANG Yong-1, 2, WANG Shi-Long-1, TIAN Zhi-Feng-3, ZHOU Jie-1, KANG Ling-1

2013, 24(11):  1473-1479. 

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 In order to avoid influence of cutting vibration on gear machining precision, it is necessary to simulate analysis the stiffness characteristic and harmonic responses of columns for large-scale NC gear hobbing machines. Based on the structural characteristics of the column of gear hobbing machines, transmission principle of hob spindle and dynamics theory, the FE simulation models of column and hob-box were set up to simulate and calculate the paramter of mode and harmonic response of the column.After the analysis of the vibration frequency of dynamic response and deformation,the variety law of vibration deformation was revealed for each order dynamics response simulation of the column. The results show that the range of resonance frequency can avoid the resonance of gear hobbing machines, the change law of column vibration deformation is revealed, the advice is proposed to improve the structure and assembly method of column, and the above researches offer theory gist and instructive reference value for the optimization design of component structure of large-scale NC gear hobbing machines.

Dual-NURBS Tool Path Fairing Method for Five-axis High-speed Machining

YANG Tang-Yong-1, FENG Jing-Chun-1, 2

2013, 24(11):  1479-1483. 

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A Fairing method for dual-NURBS tool path was proposed, smoothing the break points where the accuracy was not satisfied with Bezier dual-quaternion vector function. With the proposed method, the accuracy and G1 continuity of the whole tool-path were attained. As a result, the needs for five-axis high-speed machining are met by eliminating the abrupt changes of the velocity direction, thus improving the servo dynamics and reducing the shock of the machine tool.

Nonlinear Dynamics Analysis of Flexible Rotor Bearing System with Helical-gear

SONG Xiao-Guang-1, CUI Li-1, 2, ZHENG Jian-Rong-1

2013, 24(11):  1484-1488,1493. 

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Considering backlash, radial clearance of bearing and unbalance force,the mass, stiffness and damping matrixes of a rotor system were obtained by using finite element method, then they were assembled by an integrated method. Nonlinear dynamics model of a flexible rotor bearing system with helical-gear was established. Runge-Kutta method was used to solve nonlinear dynamics equations, and the dynamic behaviors of the system were analyzed. The nonlinear dynamics behaviors of the flexible rotor bearing system with helical-gear were discussed for effect of speed, shaft stiffness and unbalance. The results show that periodic, quasi-periodic and chaos motion occur as the speed changes. With the decrease of shaft stiffness, the range of chaos motion is decreased and the amplitude is also changed. As the unbalance increases, the range of chaos motion state is increased and range of the chaotic motion is changed.

Line Array of Grating Moving Light Modulators for MOEMS Hadamard Transform Spectrometer

YUE Qiu-Qin-1, ZHANG Zhi-Hai-2, TU Hua-2

2013, 24(11):  1489-1493. 

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According to the faint light signal fast detection in HT(Hadamard transform) spectrometer, a line array of grating moving light modulators made by MOEMS technology was proposed. The paper presented a novel HT error compensation algorithm. After the fabrication process of GMLM(grating moving light modulator) was designed based on the Al film micromachining technology, the line array device was manufactured in lab. Experimental results indicate that GMLM can work well under power supply voltage of 8.1V, and the switch frequency can reach up to 140Hz, which can satisfy the HT spectrometer requirements of fast modulation, wide spectrum, minor abrasion and errors.

IPSO-PID Servo Synchro Control on Hydraulic Broaching Machine with Dual Cylinder

NI Jing, SHAO Bin, MENG Zhen, CHEN Guo-Jin

2013, 24(11):  1494-1500. 

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In view of the shortcomings on synchro-motion of slide carriage in hydraulic broaching machine driven by single cylinder, an electro-hydraulic servo system with dual cylinder was designed and its nonlinear model was presented based on the analysis of slide carriage motion chracteristics. Then the algorithm of
 IPSO was introduced, and a IPSO-PID synchro controller similar to classical PID controller structure for electro-hydraulic servo system with dual cylinder was provided on the basis of tracking and synchronization performance. The simulation and factual application in hydraulic broaching machine show that the proposed controller has better tracking and synchronization performance than conventional PID controller has and can solve the problem of dual cylinder hydraulic broaching machine synchronous driving problem better.

Research on Statistical Method of Reliability Growth Testing Data for Multi-systems with Synchronous Corrective Actions

BO Jun, JIN Fang-Jian, CHEN Wen-Hua, WANG Meng, HU Dui-Min, SHU Xu-Xiang

2013, 24(11):  1500-1504. 

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The values of reliability assessment based on the MIL-HDBK-189, GJB/Z77 and AMSAA-BISE model for the failure data would be greater than the actual values.Herein, the expectation of each time-to-failure was fist obtained by using the hierarchical Bayesian method and least squares estimation method. Then, the growth testing data was analyzed through a new model obtained by substituting the expectation for the time-to-failure in AMSAA model. The effects of the three statistical methods mentioned above were assessed based on the Monte Carlo method. The results indicate the values of reliability assessment by applying the method proposed are closer to the actual values.

Magnetic Memory Non-destructive Testing(NDT) for Remanufacturing of Drive Axle Housing

HUANG Hai-Hong, LIU Ru-Jun, ZHANG Xi, LIU Zhi-Feng

2013, 24(11):  1505-1509. 

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In order to study the magnetic memory NDT for remanufacturing of drive axle housing, pieces of smooth stretch material with 510L were selected to analyze the change of magnetic signals at the different stages of plastic strain. Based on the tensile tests of 510L, the magnetic memory testing and detection of deformation for the drive axle housing were performed. The relationship between the deformation and the magnetic memory signals was established. The results show that magnetic memory normal component Hp(y) changes from the slash without the mutation peak into reversal with the zero crossing; when increasing strain of tensile specimen, the magnetic memory normal component gradient Kmax slowly increases in the early stage, and rapid increases when specimen appearing necking. The quantitative relationship between axle housing deformation and Kmax can be established, and the gradient Kmax appears the mutation when axle housing gets a larger deformation. Magnetic memory testing can provide the basis for damage assessment of parts to be remanufactured.

Structural Optimization Design of  B-pillar Considering Roof Crush and Side Impact Requirements in Passenger Car

LEI Fei, CHEN Xin, CHEN Guo-Dong, GUAN Feng-Jiao

2013, 24(11):  1510-1516. 

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The optimization design of B-pillar was carried out by
considering the roof strength and the safety of side impact.The inner plate of B-pillar,
as well as the outer plate,consisted of two different parts which were welded together by tailor-welded blank technology and formed by high strength steel. The type of material and the thickness of steel were treated as discrete design variables. The optimization model of the structural crashworthiness of B-pillar was established by considering the material
cost,the impact force,the intrusion and its velocity at B-pillar.The moving least square response surface and genetic algorithm were utilized to improve the crashworthiness of B-pillar.The results show that the intrusion and its velocity at B-pillar are reduced by
3.8% and 5.6% respectively.The roof strength is enhanced by 18.53% and
  the mass is reduced by 13.8%,while the material cost is unchanged.Thus,the roof strength and the safety of side impact are improved effectively.

Quality Chain Management Model Based on Product Key Characteristics

DU Wei, MO Rong, LI Shan, LI Bo

2013, 24(11):  1516-1520. 

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This paper incorporated the KCs concept to the QCM theory and a model of QCM based on KCs was proposed.Firstly,a conceptual model and a structural model of quality chain were presented.Secondly,the evolvement process of KCs in the quality chain system was analyzed.The KCs fundamental activities including identification,controlling and feedback were running in the quality chain system,furthermore the KCs flow-down and transfer implements the product quality gradually.Thirdly,a quality chain collaboration management process model was established based on KCs.Finally a framework of QCM based on KCs was proposed.

Research on Vehicle Driving Situation Identification (Part Ⅱ)——Based on Fuzzy-neural Network

TIAN Yi-1, 2, 3, ZHANG Xin-2, ZHANG Cuan-2, ZHANG Liang-2

2013, 24(11):  1521-1524,1530. 

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By using the best subset of the vehicle driving pattern, a vehicle driving situation identification model was created herein, which was based on the fuzzy-neural network. Identifying vehicle driving cycle on the urban way and highway of the Beijing, Shanghai, Guangzhou and Wuhan,the results are: except the accuracy of Beijing urban way is as 82.67%, the accuracy of other vehicle driving cycles is as 100%; and the accuracy of Beijing urban way and highway on-road driving situation is as 89.08%.

Evaluation of Difference between LNG and Diesel Heavy-duty Commercial Vehicle's Life Cycle Environmental Emission

CHU Xiao-Yue-1, YANG Yan-Beng-1, XU Jian-Quan-1, 2, CHEN Die-Song-1

2013, 24(11):  1525-1530. 

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An evaluation model of the difference between LNG and diesel heavy-duty commercial vehicles' life cycle emissions was established. Through an empirical analysis of the LNG and the diesel heavy-duty commercial vehicle, it is found that the NOx, SOx and PM of the LNG vehicle are reduced by 32.83%, 83.68% and 100% relatively comparing to the diesel vehicle, but CO emission is increased by 21.39%, the HC emission increases 7.83 times.Meanwhile, the LNG heavy-duty commercial vehicles' CO2 emission in the using phase is 6.82% less than that of the diesel vehicle, but 8.88% more in the whole life cycle.

Control for Chaos in Automobile Suspension System Based on Back-stepping Design Adaptive Sliding Mode Controller

GAO Yuan-1, 2, 3, FAN Jian-Wen-2, 3, TAN Guang-Xin-2, LUO Wen-An-2, 3

2013, 24(11):  1531-1537. 

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A self-adaptive sliding mode control method based on back-stepping design theory was presented, which was used to control chaos in the uncertain automobile suspension system with extern disturbance. The total uncertain factors in the system were estimated by self-adaptive algorithm. The asymptotic stability of controller was proved by Lyapunov theory. Simulation results demonstrate that even if suspension system exists time-variable parameters, uncertain mathematical model and different grade roads interference, this method can realize control chaotic vibration to the steady state, reduce vertical displacement, velocity and acceleration of suspension vibration very much, improve comfort and safety of driving evidently. The presented controller is independent of nonlinear term of the suspension model, and can offset the uncertain influences by adaptive estimating of disturbances. Hence, the control method has better adaptability and robustness. The research results provide a useful reference for design the controllable suspension system with good vehicle ride comfort.

Road Simulation Test of DCT Key Parts Based on RPC

JU Chi-Gong-1, QIAO Kai-1, DAN Xiao-Hui-1, TU Yong-2, YI Feng-2

2013, 24(11):  1537-1541. 

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To evaluate the fatigue reliability of DCT key parts such as valves,transducers and electronic components under the actual road vibration, a road simulation test table for DCT key parts was designed based on RPC technology together with MTS hydraulic servo actuator and control system. By arranging acceleration transducers and strain gauges near the key parts, combining with a reliability method of some enterprises, a large number of load spectrum was acquired on Xiangyang Automobile Proving Ground and analysed in the laboratory, then the final drive signals were acquired through repeated simulation iteration, and the vibration performance of DCT key parts in the corresponding road sections of Xiangyang Automobile Proving Ground was reappeared accurately and rapidly. An effective method for evaluating the fatigue reliability of DCT key parts was put forward from the tests.

Research on Failure of Wind Turbine Gearbox and Recent Development of Its Design and Manufacturing Technologies

WANG Hui, LI Xiao-Long, WANG Gang, XIANG Dong, RONG Yi-Ming

2013, 24(11):  1542-1549. 

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Large-scale, high reliability and long service duration were already the development directions of wind power equipment which also presented a number of challenges on the design and manufacturing technologies of large wind gearbox. Following an introduction to some crucial technical problems of wind turbine gearbox running, the failure mechanism of key parts, and the latest research on advanced design and manufacturing of wind turbine gearbox were discussed in detail. The gaps of research and real applications between China and overseas were analyzed. Finally, the future trends of wind turbine gearbox design and manufacturing were also prospected.

Energy Efficiency Assessment of Mechanical Manufacturing System: Characteristics, State-of-the-art and Future Trends

LIU Fei, WANG Qiu-Lian

2013, 24(11):  1550-1556. 

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The energy efficiency assessment of a mechanical manufacturing system is the systematic evaluation about energy consumption status,energy consumption processes and energy efficiency of the system. As the premise of reducing the system's energy consumption and improving energy efficiency, the assessment system has gradually been studied in the world. This paper firstly analyzed the characteristics of energy efficiency assessment for mechanical manufacturing system and, consequently, summarized four traits, namely the multiple-energy-sources feature and the multiple-layer architecture feature of the energy consumption status and the complicacy-variety feature and total life-cycle feature of the energy consuming processes and instantaneous energy efficiency. And then, based on the characteristics analysis, the current researches of the energy efficiency assessment for mechanical manufacturing system were analyzed, including the assessing contents and the energy efficiency indicators. Finally, the future trends of the energy efficiency assessment for mechanical manufacturing system were concluded. The trends can be detailed as the construction of the integrated index system and the development of the basic database for energy efficiency, the quota of the energy consumption of manufacturing products and tasks, the standardizations of the energy efficiency assessment, and the development of informationization platform for supporting energy efficiency assessment and improvement, et al.

Development and Prospects of Cymbal Underwater Transducers

BANG Hai-Jun-1, XU Wei-Qi-1, WANG Dun-Pan-2

2013, 24(11):  1556-1561. 

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The development of cymbal transducer as underwater transducer in the later 20 years was studied thoroughly. These developments included vibration modes in water, effect of material and geometry on electromechanical performance, ability for sustaining high hydrostatic pressure, shaping directional beam pattern, adopting new materials and assembling cymbal array. Several theoretical methods used on cymbal were compared and investigated. At last, key points of future development were summed up.