2018 Vol. 13, No. 6

Contens of CJSR 2018, Vol.13, No.6
Chinese Journal of Ship Research
2018, 13(6): .
[1]Key technologies and intelligence evolution of maritime UV…JIN Kefan,WANG Hongdong,YI Hong,et al (1)[2]Research status of Markov theory in unmanned systems…YAN Zheping,YANG Zewen,WANG Lu,et al(9)[3]Concept and key technology analysis of deep-sea walking-swimming robot…CHEN Hong,WANG Xinliang,WEI Wei,et al (19)[4]Application of USV to maritime safety supervision…LI Feng,YI Hong(27)[5]Full-scale simulation and analysis of self-propulsion performance of CRP-propelled high speed underwater vehicles…HUANG Yongsheng,YANG Chenjun,DONG Xiaoqian(34)[6]Review on underwater docking technology of AUV…ZHENG Rong,SONG Tao,SUN Qinggang,et al (43)[7]Review on development trend of launch and recovery technology for USV…ZHANG Xiaodong,LIU Shiliang,LIU Yu,et al (50)[8]A review of path planning and cooperative control for MAUV systems…ZHAO Rui,XU Jian,XIANG Xianbo,et al (58)[9]A real-time obstacle avoidance method for multi-AUV cluster based on artificial potential field…XU Bo,ZHANG Jiao,WANG Chao(66)[10]Method for intelligent obstacle avoidance decision-making of unmanned vessel in unknown waters…WANG Chengbo,ZHANG Xinyu,ZHANG Jiawei,et al (72)[11]Development of navigation system for large-scale and high-speed underactuated AUV…ZHAI Yunfeng,WANG Guanxue,XU Guohua,et al (78)[12]Heading control of AUV based on GA and fractional order technology…ZHAO Rui,XU Jian,WANG Miao,et al (87)[13]AUV control system and sonar target identification…ZHANG Jiamin,ZENG Qingjun,ZHU Zhiyu,et al (94)[14]Target assignment in formation reconfiguration for swarms of unmanned ships…LV Guanghao,PENG Zhouhua,WANG Dan,et al (101)[15]Task allocation of multiple autonomous underwater vehicles based on improved ant colony algorithm…LIU Ruixuan,ZHANG Yonglin(107)[16]Control system of ROV for underwater safety inspection and operation…ZHANG Guangyi,ZENG Qingjun,DAI Xiaoqiang,et al (113)[17]AUV emergency self-rescue mechanism and strategy…CHEN Zhu,XU Guohua,WANG Guanxue,et al (120)[18]Development of buoyancy regulating system for underwater glider…YANG Hai,LIU Yanji (128)[19]Research on AUV underwater landing strategy based on variable buoyancy system…SUN Qinggang,ZHENG Rong,YANG Bin,et al (134)[20]Design of intelligent diagnosis system for ship power equipment…ZHANG Yuewen,SUN Xiaolei,DING Yawei,et al (140)[21]Fault diagnosis of ship fuel system based on DPC-GMM algorithm…WEI Yi,ZHANG Yuewen,LI Bin(147)[22]Analysis on manned/unmanned aerial vehicle cooperative operation in antisubmarine warfare…XU Liang,PAN Xuanhong,WU Ming(154)[23]ASW concept of fixed-wing UAV and typical load…SU Jintao(160)
Ship Design and Performance
Key technologies and intelligence evolution of maritime UV
Kefan JIN, Hongdong WANG, Hong YI, Jingyang LIU, Jian WANG
2018, 13(6): 1-8. doi: 10.19693/j.issn.1673-3185.01293
In recent years, the technologies of maritime Unmanned Vehicle (UV) have developed rapidly, and especially because the development of artificial intelligence technology, it has made great breakthroughs in the functions and performance of the maritime UV. The development status of the maritime UV technology at home and abroad is reviewed, and then the key technologies for the maritime UV are analyzed. On this basis, a set of classification criteria for the intelligent levels of the maritime UV is proposed, and the operational capabilities and characteristics of the UVs at different intelligent levels are defined in detail, and the key technologies for evolution between levels are clarified. This provides a theoretical basis for the development of the maritime UV.
Research status of Markov theory in unmanned systems
Zheping YAN, Zewen YANG, Lu WANG, Lidong YUE, Xiaoli PAN
2018, 13(6): 9-18. doi: 10.19693/j.issn.1673-3185.01199
With the development of artificial intelligence technology, the missions to be performed by unmanned systems are more and more complicated, and the systems are required to complete given missions independently in an unknown environment. In order to solve the planning and decision-making of unknown and uncertain problems in unmanned systems, Markov theory can be used for modeling and estimation to solve such complicated issues as mission decision-making and planning, target tracking and identification, and platform-to-system communication in unmanned platforms. This paper introduces the research progress and the practical application of Markov theory in Unmanned Aerial Vehicle(UAV), Unmanned Ground Vehicle(UGV)and Autonomous Underwater Vehicle(AUV)respectively, presents the current problems and the prospects of future development and research.
Concept and key technology analysis of deep-sea walking-swimming robot
Hong CHEN, Xinliang WANG, Wei WEI, Zhi LIU, Zhesong MA, Chao Zheng, Pingpeng TANG
2018, 13(6): 19-26. doi: 10.19693/j.issn.1673-3185.01241
The deep-sea robot is very useful in deep sea engineering. Based on a comparison and analysis of current deep-sea robots, this paper proposes a novel concept for a deep-sea walking-swimming robot, the purpose of which is to swim extensively in the sea and walk stably on the seafloor. The overall proposal, specifications and characteristics of the deep-sea walking-swimming robot are introduced. After an analysis of its environment and function characteristics, such key techniques as the regulation of the robot's walking/swimming attitude, cooperative current anti-turbulence of multi-legs and multi-joints, path planning for low energy consumption, dynamic seal of deep-sea joints and integration and optimization of the overall design are presented, showing that it is quite different from traditional underwater and multi-foot robots. Finally, the research progress of the above-mentioned techniques is also presented.
Application of USV to maritime safety supervision
Feng LI, Hong YI
2018, 13(6): 27-33. doi: 10.19693/j.issn.1673-3185.01220
The maritime safety supervision such as patrol and emergency disposal has the characteristics of broad regulatory waters, rapid emergency response demand, high rescue capacity demand etc. Because of excellent autonomy, and intelligence, fast speed, strong risk resistance capacity and other advantages of Unmanned Surface Vehicle(USV), it is necessary to carry out a study on the application of the USV to the maritime safety supervision. Based on a brief description of the development and main functions of the USV, the characteristic of the maritime safety supervision is analyzed and the potential applications of the USV are demonstrated. The results show that the USV has many advantages such as low composite cost, strong risk resistance capacity, high degree of intelligence, rapid emergence response, etc, meeting the demands of the maritime safety supervision. As a conclusion, the USV is suitable for a wide range of applications to the maritime safety supervision.
Full-scale simulation and analysis of self-propulsion performance of CRP-propelled high speed underwater vehicles
Yongsheng HUANG, Chenjun YANG, Xiaoqian DONG
2018, 13(6): 34-42. doi: 10.19693/j.issn.1673-3185.01118
  Objectives  In order to numerically predict the self-propulsion factors of high speed underwater vehicles equipped with Contra-Rotating Propellers (CRP),  Methods  RANS modeling approaches are developed for vehicle resistance, self-propulsion and CRP open-water simulation. In terms of resistance and open-water performance, the modeling accuracy are validated by comparisons with model experiments. Based on quasi-steady and unsteady simulations of a high speed underwater vehicle at full scale, the self-propulsion factors are analyzed and compared.  Results  The comparison of the numerical and experimental results at the model scale indicates that the simulation error margin of vehicle resistance is less than 3%, while those of CRP thrust and torque are less than 2% and 4% respectively. The numerically simulated full-scale resistance is 3% lower than that predicted by the model test data. The self-propulsion factors yielded from full-scale RANS simulations are all reasonable in magnitude. The self-propulsion factors yielded from the quasi-steady and unsteady models differ by less than 2%, indicating that the quasi-steady model is an economical choice for engineering applications.  Conclusions  The present modeling approaches are capable of supplying self-propulsion factors for CRP design with reasonable accuracy, and are expected to enhance design accuracy and work efficiency.
Ship Structure and Fitting
Review on underwater docking technology of AUV
Rong ZHENG, Tao SONG, Qinggang SUN, Jingqian GUO
2018, 13(6): 43-49, 65. doi: 10.19693/j.issn.1673-3185.01182
Autonomous Underwater Vehicles(AUV)form an important link between water surface support platforms, submarine stations and deep sea long-term observation systems. The underwater docking technology of AUVs has long been a research hotspot at home and abroad. In the induction and analysis of AUV underwater docking technology at home and abroad, such as underwater box(cage)docking, robot or carrier-assisted docking, pole guidance docking, platform blocking cable docking and bell-mouth guidance docking, the implementation methods and structural principles of various AUV docking technologies at home and abroad are introduced, as well as the development status and development trends of docking technology. In light of the widely used bell-mouth guidance docking method, a submerged docking system for heavy-duty AUVs is introduced in detail. The experiment proves that this system has strong modularity and low requirements for roll attitude. It is suitable for AUVs of various sizes, and the docking success rate of the docking system is high. The findings of this study can provide useful references for the future development of AUV underwater docking technology.
Review on development trend of launch and recovery technology for USV
Xiaodong ZHANG, Shiliang LIU, Yu LIU, Xiaofang HU, Chao GAO
2018, 13(6): 50-57. doi: 10.19693/j.issn.1673-3185.01258
The Unmanned Surface Vehicle(USV)is one of the hot research fields of unmanned vehicle, and its launch and recovery technology has become a frontier research topic due to the difficulties in recovery guidance, docking, coupling or uncoupling and so on. Through collecting and sorting out the technical points of the launch and recovery technology for USV that has existed and been under development in domestic and abroad, this paper concludes with three kinds of launch and recovery systems, i.e. davit, stern ramp and dock cabin. Then the comparison among these three kinds is carried out in aspects of equipment configuration, space demand, wave influence, mothership speed, adaptive sea state, operation condition, launch and recovery duration, etc., and then it is concluded that the stern ramp type is more suitable for the USV; in the meanwhile, practical research direction that contributes to realizing autonomous launch and recovery is pointed out, which plays a guiding role in the development of the USV and its launch and recovery technology.
Marine Machinery, Electrical Equipment and Automation
A review of path planning and cooperative control for MAUV systems
Rui ZHAO, Jian XU, Xianbo XIANG, Guohua XU
2018, 13(6): 58-65. doi: 10.19693/j.issn.1673-3185.01028
The Autonomous Underwater Vehicle(AUV)is an important tool for ocean exploration and the exploitation of underwater resources, which plays important roles in civilian and military fields. Along with the research progress of AUVs, it has become the current development trend to cooperate on completing underwater operations by constructing the Multiple Autonomous Underwater Vehicle(MAUV)system. The MAUV system has important theoretical research significance and practical value for improving the intelligence level of underwater vehicles and developing marine equipment. In this paper, the state of the art of the MAUV is presented from the point of view of practical application and scientific research. The main methods of path planning and cooperative control for MAUV are illustrated, including artificial intelligence and formation control techniques. Finally, the research trends of MAUV are also discussed and the main topic is highlighted.
A real-time obstacle avoidance method for multi-AUV cluster based on artificial potential field
Bo XU, Jiao ZHANG, Chao WANG
2018, 13(6): 66-71. doi: 10.19693/j.issn.1673-3185.01326
  Objectives  This paper proposes a real-time obstacle avoidance method based on artificial potential field, in order to cope with the many potential obstacles in complex underwater environment which affects the movement plan for multi-autonomous underwater vehicle(AUV)cluster.  Methods  Firstly, a formation method based on dynamic network topology is adopted, and the AUV is regarded as a node in the network. The potential field function is set to meet the formation requirements. Then, based on the artificial potential field method, the potential field function is established for the region where both targets and obstacles exist simultaneously. Afterwards, the potential field function is upgraded to an exponential function, such that the AUVs can be planned online for real-time accomplishment of the mission of obstacle avoidance for multi-AUV cluster. Finally, 10 AUVs and 6 obstacles are simulated with Matlab software.  Results  The simulation results show that with this method, each AUV can successfully avoid obstacles and reach the safe area at the target point.  Conclusions  The artificial potential field function method may enable the multi-AUV to accurately avoid obstacle in real time. The advancement of this technology has important and positive significance for improving military operational capability.
Method for intelligent obstacle avoidance decision-making of unmanned vessel in unknown waters
Chengbo WANG, Xinyu ZHANG, Jiawei ZHANG, Shuo LIU
2018, 13(6): 72-77. doi: 10.19693/j.issn.1673-3185.01144
  Objectives  In order to realize intelligent obstacle avoidance of unmanned vessel in unknown waters,  Methods  an intelligent obstacle avoidance decision-making model of the unmanned vessel based on Deep Reinforcement Learning(DRL)is established. Here we analyze the problems encountered in the unmanned vessel's intelligent obstacle avoidance decision-making, propose the design criteria of the intelligent obstacle avoidance decision-making, and then accordingly establish a decision-making model based on Markov Decision Process(MDP), through which obtain the optimal strategy by value function to make the maximum returns in behavior mapping of the unmanned vessel status and to design an excitation function specially composed of target approaching, off course and safety. Finally, carry out the simulation tests respectively in static and dynamic waters.  Results  The results show that the proposed intelligent decision-making method can effectively avoid obstacles, and ensure the safe navigation of the unmanned vessel in unknown waters.  Conclusions  The proposed method can provide a theoretical reference for autonomous navigation of the unmanned vessel.
Development of navigation system for large-scale and high-speed underactuated AUV
Yunfeng ZHAI, Guanxue WANG, Guohua XU, Zhu CHEN, Xin ZHANG
2018, 13(6): 78-86, 93. doi: 10.19693/j.issn.1673-3185.01074
  Objectives  This paper details the development of a navigation system for a new model of large-scale and high-speed underactuated Autonomous Underwater Vehicle(AUV).  Methods  First, the hardware composition and software architecture of AUV navigation system are introduced in detail, and the integrated navigation system of the AUV is constructed on the basis of the VxWorks real-time embedded operating system. Considering the non-linear characteristics and fault-tolerance requirements of high-speed AUV navigation systems, Unscented Kalman Filter (UKF) technology is used in the federated filters, and a federated filter based on UKF is designed.  Results  A two-dimensional plane model of the navigation system is simulated, showing that the federal unscented Kalman filter can obtain higher accuracy and better robustness than the traditional Kalman filter method. Finally, the real-time operation and reliability of the navigation system are verified via a semi-physical simulation debugging experiment, pool test, lake test and boat test.  Conclusions  The results show that this navigation system can meet the needs of the AUV in completing its missions.
Heading control of AUV based on GA and fractional order technology
Rui ZHAO, Jian XU, Miao WANG, Xianbo XIANG, Guohua XU
2018, 13(6): 87-93. doi: 10.19693/j.issn.1673-3185.01185
  Objectives  Autonomous Underwater Vehicle (AUV) is an important tool for ocean exploration and exploitation, which plays an important role in ocean resources exploration, underwater equipment maintenance, underwater search and rescue, etc. Heading control of AUV is the fundamental function to accomplish underwater mission. At present, conventional Integer-Order PID (IOPID) controller is widely used for heading control in domestic engineering. However, its robustness is poor and parameter setting is complex.  Methods  Due to the shortcomings mentioned above, a heading controller based on Fractional-Order PID(FOPID)technology is proposed, and Genetic Algorithm(GA)is adopted to automatically tune the control gains and enable the practical implementation of the controller. The numerical simulations for PID, GA based IOPID and GA based FOPID are compared respectively by trial-and-error method.  Results  The results showed that, compared with the other two controllers, the GA based FOPID heading controller has a significantly reduced overshoot when the rise time and the steady-state error are basically equal,  Conclusions  which indicates that the AUV applying the GA based FOPID is more effective and advantageous.
AUV control system and sonar target identification
Jiamin ZHANG, Qingjun ZENG, Zhiyu ZHU, Xiaoqiang DAI, Jinyi YAO
2018, 13(6): 94-100. doi: 10.19693/j.issn.1673-3185.01192
  Objectives  In order to meet the requirements of underwater search and rescue, exploration, target detection and tracking,  Methods  we carry out a target identification test for the developed "T-SEA Ⅰ" AUV, through which a typical frame is selected for the target detection and identification from the acquired moving target images by virtue of the front-view sonar; describe the system composition and working principles of "T-SEA Ⅰ" AUV; then propose a framework for a control system in which laptop and surface control box act as a surface control unit, PC104 industrial control board acts as the main control unit of an autopilot and the PC104 camera board processes the camera images separately; use three-frame difference method to detected the sonar target, and extract the target characteristics according to a fast ellipse detection algorithm based on Hough transform.  Results  The lake test shows that the AUV runs reliably and normally and meets the requirements of underwater work; the sonar target identification is good.  Conclusions  This AUV's control system structure and target identification method can provide a reference for the development of medium and large-scale AUVs and the target identifications in other fields such as video, infrared, etc.
Target assignment in formation reconfiguration for swarms of unmanned ships
Guanghao LV, Zhouhua PENG, Dan WANG, Weitao DOU
2018, 13(6): 101-106. doi: 10.19693/j.issn.1673-3185.01362
  Objectives  To study the target assignment in the formation reconfiguration of unmanned ships, a target assignment method is proposed.  Methods  Firstly, a distance-based cost function is generated by the current positions of the unmanned ships and the fixed target points. Secondly, based on the auction theory and according to the rapidity requirement of the target assignment in the formation reconfiguration of the unmanned ship, an auction termination mechanism is proposed based on the maximum number of iterations for possible non-feasible solution in the assignment of the traditional auction algorithm, which disperses part of the simulations, thus shortening the assignment time.  Results  Finally, the simulation results show that this proposed method can quickly give an optimized target assignment scheme for the formation reconfiguration of swarms of the unmanned ships when compared with the classical Hungarian method.  Conclusions  The proposed method herein can provide an effective reference for the target assignment in the formation reconfiguration of swarms of the unmanned ships and for the study on the autonomous decision-making of the unmanned ships.
Task allocation of multiple autonomous underwater vehicles based on improved ant colony algorithm
Ruixuan LIU, Yonglin ZHANG
2018, 13(6): 107-112. doi: 10.19693/j.issn.1673-3185.01029
  Objectives  With the submarine topographic survey mission of the Multiple Autonomous Underwater Vehicles (MAUV) as the background, the optimal task allocation method of MAUV is proposed on the basis of an improved ant colony algorithm.  Methods  The task allocation model is first established and the basic ant colony algorithm subsequently improved. The improved ant colony consists of multiple groups. In order to enhance the adaptive and global search ability of the algorithm, the ant selection method of the remaining task execution capability, new heuristic function and updated global pheromone method are improved. In local searches, the convergence rate of the optimal solution is further accelerated by the 2-opt algorithm.  Results  The Matlab simulation results show that the improved ant colony algorithm can effectively improve the task allocation efficiency of MAUV while also providing a good balance between the distance of the voyage and the cost of the consumption.  Conclusions  This article can provide references for submarine topographic survey mission assignment in real environments.
Control system of ROV for underwater safety inspection and operation
Guangyi ZHANG, Qingjun ZENG, Xiaoqiang DAI, Chunlei ZHU, Hongjie LING
2018, 13(6): 113-119. doi: 10.19693/j.issn.1673-3185.01167
  Objectives  In order to achieve safety inspections for surface attachments on hulls, dams and underwater steel structures according to the requirements of removing attachments, a new Remotely Operated Vehicle(ROV) equipped with cables for underwater safety inspection and operation is developed. This type of ROV uses different manipulators for different tasks to achieve the function of gripping and cutting, so as to ensure the removal of the attachments on the structure.  Methods  Here we describe the composition and principles of a control system of the ROV for underwater safety inspection and operation; this control system uses Arduino microcontroller as a control panel signal acquisition tool, industrial personal computer as a platform of the water surface monitoring system, zero buoyancy umbilical cable consisting of two pairs of twisted pairs and a pair of power cables as the means of the signal power transmission, and ARM embedded underwater control system as the main control unit; we establish the ROV dynamics model, and design the Generalized Predictive Controller(GPC)of ROV heading control.  Results  The commissioned system is normal; tank test and lake test in Qiandao Lake prove that the stability, reliability and real-time performance of the entire control system meet the design requirements and the requirements of underwater safety inspection and operation.  Conclusions  The design scheme and control algorithm of this system can provide reference for the control system of other ROVs.
AUV emergency self-rescue mechanism and strategy
Zhu CHEN, Guohua XU, Guanxue WANG, Yan LIU, Yunfeng ZHAI, Yu ZHENG
2018, 13(6): 120-127. doi: 10.19693/j.issn.1673-3185.01027
  Objectives  In order to guarantee the navigation safety of high speed Autonomous Underwater Vehicles(AUV), a new type of practical and reliable emergency system is developed.  Methods  First, this paper introduces the composition of the emergency self-rescue system and analyses and designs the reliability of the system. Secondly, it mainly focuses on the emergency mechanism and strategies, which include the multi-channel data collection mechanism, active emergency switch mechanism and automatic fault priority setting mechanism, as well as the contents of the emergency action methods. Next, an expert emergency decision-making model is designed to output action decisions to handle the faults. Discrete steering rules are introduced to raise the AUV in emergency conditions. Finally, based on the VxWorks real-time operating system, the emergency system control software is coded and hardware in the loop simulation carried out.  Results  The results show the feasibility of the emergency self-rescue mechanism and strategies.  Conclusions  As such, the emergency system and mechanism introduced in this paper can make up for shortages in traditional emergency means, which has important reference value for the self-rescue methods of submarine-shaped AUVs.
Development of buoyancy regulating system for underwater glider
Hai YANG, Yanji LIU
2018, 13(6): 128-133, 165. doi: 10.19693/j.issn.1673-3185.01238
  Objectives  Buoyancy regulating system is a key component of an underwater glider for controlling submerging and surfacing statuses and gliding speed of the underwater glider. To further study the buoyancy regulating system,  Methods  we carry out theoretical analysis and CFD for the underwater glider and its buoyancy regulating system to obtain the buoyancy regulating value, which is an important design parameter; develop a buoyancy regulating system with both oil outlet and oil return passages, that is, a high-pressure plunger pump for oil outlet in deep water and a low-energy gear pump for oil return in shallow water. We conduct the tests for the oil outlet and oil return characteristics and the energy consumption under different pressure conditions.  Results  The results show that the oil outlet is normal under the pressure of 2.5 MPa and the oil return is normal under atmospheric pressure. The developed test device can simulate the marine pressure in the actual operating environment of the underwater glider.  Conclusions  The study results can provide useful references for the engineering application of the buoyancy regulating system.
Research on AUV underwater landing strategy based on variable buoyancy system
Qinggang SUN, Rong ZHENG, Bin YANG, Mozhu LI
2018, 13(6): 134-139. doi: 10.19693/j.issn.1673-3185.01059
  Objectives  The underwater landing of an Autonomous Underwater Vehicle(AUV)is a way to achieve underwater long-term latency and fixed-point observation which is conductive to the better control of changes in the marine environment.  Methods  This paper mainly introduces the fundamental structure and main functions of an AUV which is based on the oil sac type variable buoyancy system. Two kinds of underwater landing strategies are established:controlled buoyancy vertical dive landing and sailing dive and controlled buoyancy vertical landing. The target point deviation, energy consumption and AUV take-off from the bottom are analyzed, and the actual underwater landing experimental verification is carried out in a lake.  Results  The experimental results show that the AUV is able to steadily land underwater and take off from the bottom safely with this variable buoyancy system. The control strategy of sailing dive and controlled buoyancy vertical landing can save more energy, and the landing point is more accurate than with the strategy of controlled buoyancy vertical diving.  Conclusions  As such, the control strategy of sailing dive and controlled buoyancy vertical landing is more in line with the demands of future practical application.
Design of intelligent diagnosis system for ship power equipment
Yuewen ZHANG, Xiaolei SUN, Yawei DING, Peiting SUN
2018, 13(6): 140-146. doi: 10.19693/j.issn.1673-3185.01209
  Objectives  In order to adapt to the development of unmanned ships, strengthen the ship-shore integrated management of ship power equipment, reduce the workload of marine engineers, and realize on-condition maintenance of ship power equipment, this paper designs an intelligent diagnosis system of ship power equipment allowing for ship-shore integrated management.  Methods  According to the functions and features, the health status of components is evaluated with the single parameter threshold method and the radar chart, and the evaluation results are presented in the form of health scores. For components scored below 70 points, the system automatically enters the decision-making support interface, and the corresponding decision for a fault is provided for the engineer's reference. Taking the training ship "yukun" as the target ship, the intelligent diagnosis system of the actual ship power equipment is verified.  Results  The results of actual ship verification show that the intelligent diagnosis system of ship power equipment has high accuracy and operability, which realizes the transformation from "breakdown maintenance" to "on-condition maintenance".  Conclusions  The intelligent diagnosis system of ship power equipment helps improve the safety of ship operation and has certain practical value.
Fault diagnosis of ship fuel system based on DPC-GMM algorithm
Yi WEI, Yuewen ZHANG, Bin LI
2018, 13(6): 147-153, 165. doi: 10.19693/j.issn.1673-3185.01262
  Objectives  The traditional Gaussian Mixture Model(GMM)has the inherent shortcoming of slow convergence which can easily lead to over-fitting and cause the parameter calculation to fall into a local optimum. As such, it is not suitable for the fault diagnosis of marine fuel systems.  Methods  A fault diagnosis method for a ship fuel system based on the DPC-GMM algorithm is proposed. First, the GMM and parameter estimation algorithms are analyzed. Combined with the Density Peaks Clustering(DPC) algorithm, GMM parameters corresponding to the state of the fuel system of ship are calibrated to achieve the unsupervised diagnosis of the failure of a ship's fuel system. Based on the obtained fuel system failure data, the proposed method is verified.  Results  The experimental results show that this method has higher recognition accuracy and faster recognition speed than the traditional Back Propagation(BP)neural network and Support Vector Machine(SVM) diagnosis algorithm.  Conclusions  The analysis results have important guiding significance for the fault diagnosis of marine fuel systems.
Weapon, Electronic and Information System
Analysis on manned/unmanned aerial vehicle cooperative operation in antisubmarine warfare
Liang XU, Xuanhong PAN, Ming WU
2018, 13(6): 154-159. doi: 10.19693/j.issn.1673-3185.01072
  Objectives  Cooperative operation of Manned/Unmanned Aerial Vehicle(MAV/UAV)hybrid formation in antisubmarine warfare can give full play to both MAV and UAV to improve the operational efficiency significantly, being one of the typical air operation modes in the future under the network condition.  Methods  This paper analyzes the operational advantages and technical challenges of cooperative operation of MAV/UAV in antisubmarine warfare, and introduces the theoretical research status and equipment development of this operation at home and abroad. On this basis, this paper focuses on five typical operation modes in antisubmarine warfare, and based on the antisubmarine mission requirements, puts forward the cooperative operation planning, cooperative data chain, capacity requirement for antisubmarine warfare aircraft and UAV platform and the key technologies to be solved to achieve cooperative antisubmarine warfare.  Results  It is shown that cooperation of MAV/UAV has great potential in antisubmarine warfare,  Conclusions  and the findings provide guidance for future UAV equipment development and MAV/UAV cooperative antisubmarine warfare training.
ASW concept of fixed-wing UAV and typical load
Jintao SU
2018, 13(6): 160-165. doi: 10.19693/j.issn.1673-3185.01133
There is broad prospect of the fixed-wing Unmanned Aerial Vehicle(UAV)in the application of the Anti-Submarine Warfare(ASW)because of its characteristics, such as low cost, long endurance, good maneuverability and wide range of searching. But the ASW theory and engineering practice for the fixed-wing UAV has just started, still facing a series of challenges in the development of the operation concept, the design of the operation process and the integration of the ASW loads. Here we introduce the development of the fixed-wing anti-submarine UAV in foreign countries, summarize the ASW concept and ASW missions of the fixed-wing UAV, analyze the operational control of the fixed-wing anti-submarine UAV, describe the basic composition and functions of the typical ASW loads of the "search-attack-submarine" type fixed-wing UAV, and thus provide reference for the demonstration, development, design and use of the ASW fixed-wing UAV.