Available online at ScienceDirect. Procedia Engineering 174 (2017 )

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1 Available online at ScienceDirect Procedia Engineering 174 (2017 ) th Global Congress on Manufacturing and Management, GCMM 2016 Survey on Flexible Shipbuilding Technologies for Curved Ship-Blocks Wu Zhao-hui a, Du Ji-wang b*,zhu Ming-hua a, Fan Xiu-min b a Jiangnan Shipbuilding (Group) Co., Ltd., 988 Jiangnan RD, Shanghai , China b Shanghai Jiao tong University,800 Dongchuan RD, Shanghai , China Abstract Curved blocks are important structured components of a ship. At present time, the assembly and welding process of curved blocks are done mainly manually, which has been the bottleneck of ship construction for a long time. Through lots of research, technical discussion and analysis, the implementation of flexible construction of ship curved block will serve as an important method to solve the problem. The literature application statues of three kind of key technologies used for flexible ship building are analyzed in the paper. The first one is advanced design method, the second is flexible process technology & equipment and the third one is precision measurement technology. Based on the analysis results, it is clear that these advanced technologies are not well used in curved-block shipbuilding. Taking the advanced technology of precision assembly for large components into consideration, a framework of intelligent flexible construction of curved hull block based on these key technologies is proposed, which indicates the trend of research and development in the field of flexible intelligent shipbuilding in China The Authors. Published by Elsevier by Elsevier Ltd. This Ltd. is an open access article under the CC BY-NC-ND license ( Peer-review under responsibility of the organizing committee of the 13th Global Congress on Manufacturing and Management. Peer-review under responsibility of the organizing committee of the 13th Global Congress on Manufacturing and Management Keywords: Large structured part; Curved block; Flexible fixture; Precision measurement; Flexible shipbuilding 1. Introduction Shipbuilding involves a comprehensive processing and assembling process, and it is also a labor-intensive, capital intensive and technology intensive industry [1]. Three major shipbuilding indicators of china have been ranked first in the world since 2010[2]. However, the shipbuilding enterprises in our country still have the problems of high * Corresponding author. Tel.: ; fax: address: yjk888@sjtu.edu.cn The Authors. Published by Elsevier Ltd. This is an open access article under the CC BY-NC-ND license ( Peer-review under responsibility of the organizing committee of the 13th Global Congress on Manufacturing and Management doi: /j.proeng

2 Wu Zhao-hui et al. / Procedia Engineering 174 ( 2017 ) occupancy rate and long construction period compared with Japan, South Korea and other developed countries. This has greatly restricted the development of shipbuilding industry in our country. Therefore, the improvement of existing shipbuilding mode and gradually implement modern shipbuilding has become the inherent requirement of the development of Chinese shipbuilding industry. Curved blocks are important structured components of a ship. At present time, the assembly and welding process of curved blocks are done mainly manually, which has been the bottleneck of ship construction for a long time. Because these blocks are very difficult to construct, the building period is very long and the building quality is difficult to control. There are three main problems in the construction of curved blocks in our country, the first is the contradiction between the existing shipbuilding mode and digitized design method, the second is the contradiction between the longer preparation period and rapid response of the market and the last is the contradiction between the traditional assembly coordination method and the flexible assembly based on online detection technology. In order to solve and reconcile the contradictions, the following aspects of technological innovation need to be carried out to realize intelligent flexible shipbuilding: Digital design and simulation. The implementation of digital shipbuilding is a necessary foundation for the intelligent shipbuilding. In this way, the shipbuilding enterprises can break the technical barriers from design to construction of a ship, simulate the construction of the ship to find out potential problems and improve production efficiency. Flexible manufacturing process. Due to the diversity of ship orders and the complexity of products, the production planning and execution organizing are complicated. The multi- function of a flexible fixture can effectively guarantee the smooth construction of a complex ship. High-precision inspection equipment. The construction of large ships involves the processing and assembling of thousands of parts. The machining precision and assembly accuracy of the parts will affect the assembly quality of the whole ship. Precision inspection equipment is an important means of quality assurance. In summary, research on these key issues is urgent. This paper analyzes the current situation of these problems, uncovers the deficiencies in the existing research and puts forward the direction of the further research. 2. Key technologies of digital shipbuilding Digital shipbuilding is based on the knowledge fusion of shipbuilding process, which is characterized by digital modeling, simulation and optimization [3]. In this mode, information technology, advanced digital manufacturing technology, advanced shipbuilding technology and modern shipbuilding mode are comprehensively applied in various stages of a ship s whole life, which contains design, manufacture, testing, management and maintenance. Digital manufacturing has become the main technical means in shipbuilding industries, as its characteristics of quick response, high quality, low cost and good flexibility. Through digital product development, design, testing, manufacturing and management platform, ships can be displayed in digital modeling and digital prototyping, manufactured by digital control method, tested by virtual prototype and digital simulation and supervised in modern shipbuilding mode. These techniques constitute the core of digital shipbuilding. In the field of digital design and manufacturing, lots of advanced shipbuilding companies in worldwide are widely used commercial design software and shipbuilding system. With the development of CAD/CAE technology, the design of a ship has entered into the 3D era. The design cycle of new product development is effectively reduced. CAD/CAM system, NAPA three-dimensional CAD system software and Tribon shipbuilding system have been widely used in various countries around the world. Among them, the Tribon shipbuilding system is the most popular in the shipbuilding industry, and has been favored by many shipyard. In the field of integrated virtual simulation of ship digital construction, shipyards of the worldwide mainly developed virtual simulation software system fitting for the needs of themselves, because they have different shipbuilding mode and management mode. The design and manufacturing process is closely combined with the digital technology, which is the core of the digital construction technology of ships. In the field of ship building simulation, the research on the related technology of shipbuilding simulation starts very early. Some shipyard has put forward different theoretical system structure and developed some commercial software.

3 802 Wu Zhao-hui et al. / Procedia Engineering 174 ( 2017 ) Computer simulation technology was carried out very early in the United States. The DARPA proposed a new generation of ship design system named Virtual Simulation Based Ship Design. In this system, the virtual prototype technology and simulation technology were integrated to analyze the process of design, manufacture and maintenance of a ship [4].In September 2000, the six largest shipbuilding company in the United States jointly built a virtual enterprise based on Information Technology (dynamic alliance).this alliance contained shipbuilding contractors, suppliers and ship user, inspector and research department. They developed the first shipbuilding CALS system of the world based on interaction design and construction control method. In April 2002, Samsung heavy industry also launched the digital shipbuilding system development plan and developed a digital shipbuilding system in two years later [5].This system can simulate the whole shipbuilding process from steel plate cutting to ship launching in the virtual environment. The designer of shipyard can simulate and optimize the human s load, construction method, logistics and automation application before the construction of the ship, so as to improve the production efficiency greatly. This system was regarded as a milestone indicating the changeover from traditional ship manufacturing industry to digital development in shipbuilding industry. Maier shipyard in Germany began to implement the ship virtual manufacturing plan in The project used the latest product life cycle management system of BIM. The designer of shipyard could complete the design and development of ships in a three-dimensional virtual environment in this software system According to the test, the time of ship design could be shorten by 30%, building time decreased by 20%, and the product catalog reduced by 50%. Daewoo shipyard launched the simulation system of the construction process of the ship based on discrete time simulation kernel in 2010[6, 7]. Based on the previous experience of ship construction and digital technology, engineers could built a virtual shipyard in the system, which could simulate the whole shipbuilding process from steel plate cutting to ship launching. SembCorp shipyard in Singapore developed a ship block scheduling simulation platform which could carry out the simulation and optimization of sectional construction planning and dynamic scheduling in 2011[8]. The development of digital shipbuilding technology in China started relatively late. With the attention of shipbuilding enterprises, some software such as ship logistics system, ship design system, ship performance computing system, and ship production planning system has been developed and gradually applied in the process of ship building. Hudong Zhonghua shipyard developed its own enterprise information system HDS-CIMS and shell, outfitting and painting integration of ship product design system independently. These software have replaced the imported design software gradually. Waigaoqiao shipyard has developed the software system SEM (shipbuilding enterprise management system) independently. Relative departments of the company are currently to promote the application of SEM. Jiangnan shipyard invested a lot in hardware and software systems. The research institute in Jiangnan shipyard is carrying out the research of heterogeneous electronic model transformation with Shipbuilding Technology Research Institute (STRI), which is expected to make a breakthrough in this area. Shipbuilding Technology Research Institute has been committed to the research of shipbuilding information technology, and developed a three-dimensional design and manufacturing system (SB3DS) [9]. Founded in 2008, the National Engineering Laboratory of digital shipbuilding committed research of information integration technology, virtual manufacturing technology and precision shipbuilding. Shipbuilding industry of the world has entered the digital stage now. In addition to commercial soft wares, advanced shipbuilding enterprises carried out the research on resource integration, optimization and simulation technology. By means of 3D modeling, computer graphics, virtual simulation technology and other theories and methods, the quality, it is much easier to evaluate cost and cycle of ship construction. These technologies are integrated together in a combination of theoretical method and develop application technology system to ensure the quality and efficiency of ship construction.

4 Wu Zhao-hui et al. / Procedia Engineering 174 ( 2017 ) Flexible fixture&jigs technology Fixture&Jigs are essential equipment for the construction of curved hull block, the quality and efficiency of ship construction depend on the assembly accuracy of the curved hull block on jigs. As one of the most important equipment in ship building, how to realize its flexibility has become a focus of research all of the world. At present, some small and medium-sized shipyard still use traditional jigs in our country. Some first-class shipyard such as Waigaoqiao shipyard, Guangzhou shipyard has begun to use the tubular active jigs. In contrast, shipyard in japan has begun to use the tubular active jigs in the 50 s [10]. Although the tubular active jigs has many technical improvement, it still cannot fully meet the flexibility needs of modern shipyard. How to reduce the material and consumption, to speed up the response time of the jigs, to improve the quality of shipbuilding and reduce the construction period of the ship have become an urgent problem need to be solved, which has also become a research topic of scholars. The flexibility of shipbuilding is originated from the concept of "multi point forming", which is based on the characteristics of flexible and digital manufacturing of multi point forming equipment. David E.Hardt [11-13] in MIT has carried out the research on the flexible bracket to realize automation for more than ten years and applied to the forming experiment of thin plate parts. By using the closed loop control principle to measure the height of a base body, and thus to control the forming precision, it was an important research direction for the modern flexible bracket technology. At present, Jiangsu University of Science and Technology is the main academic institution that has carried out the research on flexible jigs. She Jianguo, etc. focused on the structure design of flexible jigs which can adjust the height of the lead screw to meet the change of the height of the hull surface. The bracket was designed to realize the assembly line system [14]. In view of the strength check of the horizontal and vertical adjustment mechanism in the flexible jigs, the structure optimization was carried out by using the Pro / Mechanic finite element analysis software [15]. The research team led by Professor Wangzhi proposed the use of a flexible bracket to ensure line of the hull block. The template which was supported by ship hull was changed into a lifting hydraulic top rod, and adjustable structure of the hydraulic head rod could satisfy the height variation of the ship shape [16]. The corresponding control system based on internet communication was developed, which can collect the height of top poles in real time so as to realize the fixture brackets control as a whole system [17]. Jiangnan Shipyard has tried to make and use NC jigs for curved hull block in shipbuilding for the first time in China [18]. It proposes a new type of NC flexible jigs which kept the advantages of existing jigs. The application of flexible NC jigs could realize the fast and accurate positioning and assembling of curved block parts, so as to improve the quality and increase the efficiency of the construction of curved blocks. Flexible technology and computer aided technology can be used to realize the automation of flexible NC jigs. It can produce great economic significance to reduce the labor intensity, speed up the labor productivity, improve the processing precision and reduce the cost of rework. 4. Precision measuring technology The manufacturing of high-quality products depends not only on high precision processing equipment, also requires high-precision inspection equipment. The introduction of precision measurement technology in shipbuilding is the inevitable demand of modern shipbuilding Parts machining/welding quality inspection The hull surface is a complex 3D curved surface with double degree of curvature, which cannot be described by regular analytic surface [19]. At present, lots of research methods have been developed in detection of some basic geometric elements such as point, line, surface, circle, sphere, cylinder and so on[20]. The surface precision measurement technology for curved hull surface is becoming an urgent need to study. At present, the principle of detection technology for free surface of ship parts is the same as parts surface detection in other industries, such as automobile and aerospace industry. The achievements of general technology research can be applied to the surface inspection of ship parts. Traditional detection methods mainly include manual

5 804 Wu Zhao-hui et al. / Procedia Engineering 174 ( 2017 ) detection in off-line detection. The low detection efficiency and poor accuracy not only affects the processing efficiency, but also decreases the equipment utilization s rate and the product processing quality. Installing a trigger test head on CNC machine tools does not change the original hardware and software system of numerical control equipment. In this method, the main function of the industrial three coordinate measuring machine is transplanted to the NC machining equipment, which can effectively improve the detection accuracy and avoid the subjective error due to the manual operation [21]. At present, some key technical difficulties in on-line detection of curved surface are measurement and path planning, error compensation and measurement precision of the surface. The measurement of free form surfaces is divided into two steps. The digital processing of surface is carried out according to the rule of "Surface-Curve-Point set -Test suite" firstly. And then the motion path of the measuring head is defined for contact-type measurement. The measuring point density can vary in accordance with the measured surface curvature. The greater the curvature, the denser the sample points. Li Jian[23] proposed a method to arrange measuring points adaptively according to the measured surface specific geometry, in which the measuring point distribution density varies with the changing curvature. By this method, the precision of measuring point can be optimized and the measurement efficiency can be improved. Shao Wei [24] proposed a measurement path planning method based on position information. Adaptive control theory was applied in the measuring head to realize automatic tracking control. In order to realize high speed, precision and scanning measurement of free surface, the measuring head was set to adjust its position with the change of the surface automatically. As the detection and processing are carried out on the same machine tools, the detection head is generally installed in the tool magazine. The detection process brought into the error of the machine itself which affects the accuracy of the measurement. Cho M W [25] proposed the PNN (neural network Polynomial) model established for the real time data measured by the system, which describes the relation between the errors of various machine tools under certain machining conditions. Y.Shen [26] considered that the pretravel error was the biggest factor affecting the accuracy of the probe based on the normal direction of the measuring point. Layer back-propagation network neural (BP three-hidden) analysis method is proposed to compensate the error of the proposed method. On line detection technology for curved surface parts has made great progress in the aspects of system development, data acquisition, path-planning and error compensation. However, the measurement speed still needs to be improved due to the complexity of environment and the measurement error factors Assembly accuracy detection The traditional method of hull block assembly is completed with the use of crane lifter lifting block segments one by one. The adjustment and positioning of the segments are carried out by using a plurality of elastic screws or oil tops [27]. The main disadvantage of this technique is that the crane utilization rate is relatively low, the cycle is long, labor intensity of workers is high and the positioning accuracy for assembly is poor. Information sensing technology and data acquisition methods are the premise of the integration of industrial automation and information technology in intelligent manufacturing. MAA (Measurement Assisted Assembly) is one of the integrated intelligent manufacturing technology, and it is also the inevitable trend of digital intelligent docking technology for ships and other large scale products [28]. Right now, hull and folding butt joint tracking and measurement technology is still in the preliminary stage, which is mostly learning from the aircraft and spacecraft cabin docking measurement technology. We can predict the development direction of the ship block jointing tracking technology based on the summary of relative measurement technology. Measurement of component position is more commonly used by laser tracker, indoor GPS, camera system etc. Indoor GPS can only be used in a fixed space, and it is vulnerable to interference from the signal which may cause the error. Comparatively speaking, laser measurement technology has the characteristics of non-contact, no guide rail, fast detection speed, good portability and so on. It is widely used and studied. Zhou Jihua [29] studied the function, principle and measurement method of the laser tracking measurement technology. A flexible assembly technology system was proposed on this basis, and it was integrated with a number of advanced digital technologies. Mei Zhongyi [30] studied the problem of aircraft components assembly positioning. The research of technology and principle of digital flexible assembly for aircraft components docking based on laser tracking and positioning was carried out. The laser tracking measurement system was developed based on the laser

6 Wu Zhao-hui et al. / Procedia Engineering 174 ( 2017 ) tracker software package. A number of experts [31-34] conducted in-depth research on flexible assembly of large parts, they all emphasized that the application of laser measurement technology in flexible assembly of large parts was a growing trend. The laser tracking and positioning measurement system is connected through the Ethernet. The measurement data obtained by the laser tracking and positioning system are directly fed back to the system computer after processing the measured data through the processing unit. The computer is then compared with the position of the exact mathematical model to obtain the correct value of the assembly position, which can guide the assembly process. Laser measurement technology is widely used in flexible docking system of aircraft and missile cabin. Such systems generally contain digital measurement system, position and attitude adjustment mechanism, control system and data processing system [35]. The digital measuring system is used to measure the position and orientation of the components quickly and accurately. The data processing system is used to analyze and calculate the theoretical position. The control system is used to adjust the position and attitude of the components. The digital measurement system has just been introduced into section connection of shipbuilding processes, there is still much room for future research and application in ship industry. 5. Discussion Modern shipbuilding technology is moving towards a higher degree of automation, mechanization, modular, integrated and intelligent direction. Throughout the shipbuilding industry in recent years, the development of technology has made considerable progress. Advanced manufacturing technology from aviation and aerospace industries has gradually been introduced into the field of shipbuilding. It can be predicted that the advanced ship manufacturing technology is still the key focus of research in a long period of time. The key research is: The system integration of simulation software and measurement equipment. Research on high speed and precision technology for on-line measurement, the fusion technology of a variety of sensor measurement data. The development of precise bracket control system and flexible assembly system. Intelligent flexible manufacturing system should have four basic characteristics: state perception, real time analysis, autonomous decision-making and precision implementation. The real-time operation information and data obtained from the sensor system can be used to do the real-time simulation in the virtual simulation system. The expert system can make the decision and then feed back to the actuator according to the simulation results [36]. The framework of the intelligent flexible construction system (Fig. 1) for curved ship blocks can be proposed on the concept of intelligent flexible manufacturing system. There are four main modules in the framework of the system, which is corresponding to four stages of the construction of curved ship blocks. These four modules also reflect the integrity of the connotation of intelligent flexible manufacturing system. Field data acquisition. With the help of high precision sensors and laser ranging equipment, engineers can obtain the current state of the equipment remotely. These data stored in the database is the basis for simulation analysis in the system. Real-time simulation and evaluation. The data obtained from the shop floor real-time is processed by virtual simulation software to simulate the future operation of the equipment. The simulation results provide support for decision making. Expert system for curve blocks. The next stage of production planning is established by comparing the experience gained from the knowledge database with the simulation results. The modification and enlargement of the knowledge data base are along with production. Flexible control system of jigs. This module is the core component of the system. As a main equipment using in the construction of curved ship blocks, system of jigs can realize functions such as surface perception, fault detection and network control.

7 806 Wu Zhao-hui et al. / Procedia Engineering 174 ( 2017 ) Summary Fig. 1. The framework of the intelligent flexible construction system for curved ship blocks. The flexible manufacturing of curved surface block is at the breakthrough stage of single point digital manufacturing technology. Relative technologies are developed in the direction of the integration of the flexible production line. The key technologies mentioned in this paper are the important foundation and supporting technology for the intelligent shipbuilding. And they are also the most important technologies to solve the efficiency and quality bottleneck problem of domestic shipbuilding industry. It can improve the level of digital application of shipbuilding enterprises, and promote the update of enterprise management philosophy, management mode and management method. The research of key technology improves the overall capability of shipbuilding industry, promotes the transformation of shipbuilding industry to intelligent production mode, and strengthens the core competitiveness of shipbuilding industry. China is in the critical period of the "made in China 2025", it is a new challenge and a good opportunity to realize intelligent shipbuilding. Acknowledgements This work is supported by National Basic Research Major Project (A ). References [1] Xie Ziming,Xue Zengfeng. Key technologies of digital shipbuilding. Naval Architecture and Ocean Engineering,2006(1): [2] Yiting Zhan. Research on Key Technologies of Soft Platform Supporting Ship Digital Design.Dalian University of Technology,Dalian,2008. [3] Wu Qiang. Some Key Technologies of Digital Manufacturing for Ship.Shipbuilding of China,2005,46(2): [4] Andrews D, Casarosa L, Pawling R. Integrating the simulation of operations into preliminary ship design. Journal of Experimental Biology, 2002, 205(14): [5] Lee K, Shin J G, Ryu C. Development of simulation-based production execution system in a shipyard A case study for a panel block assembly shop. Production Planning & Control, 2009, 20(8): [6] CHA J H, ROH M. Combined discrete event and discrete time simulation framework and its application to the block erection process in shipbuilding. Advances in Engineering Software, 2010, 41(4):

8 Wu Zhao-hui et al. / Procedia Engineering 174 ( 2017 ) [7] CHA J H, PARK K P, LEE K Y. Development of a simulation framework and applications to new production processes in shipyards. Computer-Aided Design, 2012, 44(3): [8] Liu Z, Chua D K, Wee K H. A Simulation Model for Spatial Scheduling Dynamic Block Assembly in Shipbuilding. Journal of Engineering, Project, and Production Management, 2011, 1(1): [9] CAO Yu-jiao. Development actuality about the digital shipbuilding in our country. SHIP ENGINEERING,2008,30(3):6-9. [10] Kang W, Lu C, Gao X, et al. Research on the Industrial Design Method of Control Panel Based on Man-Machine Engineering Restriction. The International Conference on Computer-Aided Industrial Design &, Conceptual Design. Chinese Mechanical Engineering Society, 2008:7-11. [11] Hardt D E, Webb R D, Suh N P. Sheet Metal Die Forming Using Closed-Loop Shape Control. CIRP Annals - Manufacturing Technology, 1982, 31(1): [12] Walczyk D F, Hardt D E. Design and analysis of reconfigurable discrete dies for sheet metal forming. Journal of Manufacturing Systems, 1998, 17(6): [13] Rzepniewski A K, Hardt D E. Development of general multivariable run-by-run control methods with application to a sheet metal forming process. International Journal of Machine Tools & Manufacture, 2008, 48(5): [14] She Jianguo,GU Yongfeng. Analysis and design of flexible bracket based on production center shipbuilding method. SHIP SCIENCE AND TECHNOLOGY,2008,30(1): [15] GuYong-feng, Yang Chen, She Jian-guo. Research on three-dimensional modeling method of flexible bracket based on group technology in simulation system. Ship Science and Technology, 2015(6): [16] Ding Cha. Key Technologies of Flexible Bracket Control System Based on ARM. Jiangsu University of Science and Technology, [17] Wang Zhitong. Research on Flexible Bracket Control Network Architecture and Surface Fitting Algorithm. Jiangsu University of Science and Technology, [18] Song Jun-jie, Yu Yang, Wang Jian, et al. Research on Flexible Manufacturing Technology Based on NC Jigs for Curved Hull Block. NAVAL ARCHITECTURE AND OCEAN ENGINEERING,2016, 32(2): [19] Wang Ming-yan Jia Chuan-ying. Ship surface NURBS model and display with OpenGL. JOURNAL OF DALIAN MARITIME UNIVERSITY, 2005, 31(1): [20] Li Y, Gu P. Inspection of free-form shaped parts. Robotics and Computer-Integrated Manufacturing, 2005, 21(4 5): [21] Zhu Jincai, Gao Jian, Chen Xin. State-of-the-art of On-line Inspection Technology for Parts with Free-form Surface.MACHINE TOOL & HYDRAULICS,2007, 35(8): [22] Lai Xin-min, Huang Tian, Chen Guan-long, et al. Adaptive Sampling of Digitizing for the Free-Form Surface. JOURNAL OF SHANGHAI JIAOTONG UNIVERSITY,1999,33(7): [23] Li Jian, Wang Wen, Chen Zichen. State Searching Adaptive Measuring Technique for Free-form Surface Parts. CHINESE JOURNAL OF SCIENTIFIC INSTRUMENT, 2002, 23(5): [24] Shao Wei, Guo Junjie. Surface online measurement planning based on acquired real state information. Manufacturing Technology & Machine Tool, 2012(6): [25] Cho M W, Seo T I, Kwon H D. Integrated error compensatiojn method using OMM system for profile milling operation[j]. Journal of Materials Processing Technology, 2003, 136(1): [26] Shen Y, Moon S. Error compensation of coordinate measurements in computer-integrated manufacturing using neural networks. Journal of Materials Processing Technology, 1996, 61(1): [27] Zheng Xiong-sheng, Rui Xiao-song. Automatic Assembling Control System of Large Ship Body Section Based on PLC. Ship Engineering, 2011, 33(3): [28] Wen Ke, Du Fuzhou. Key technologies for digital intelligent alignment of large-scale components. Computer Integrated Manufacturing Systems,2016(3): [29] Zou Ji-hua,Liu Zhi-cun, FAN Yu-qing. Large-size airplane parts digital assembly technology. COMPUTER INTEGRATED MANUFACTURING SYSTEMS,2007, 13(7): [30] Mei Zhongyi, Fan Yuqing. Flexible assembly technique for aircraft parts joining based on laser tracking and positioning. JOURNAL OF BEIJING UNIVERSITY OF AERONAUTICS AND ASTRONAUTICS, 2009, 35(1): [31] Song Likang, Zheng Tangjie, Huang Shaohua, et al. Aircraft Intelligent Assembly Manufacture System Construction and Its Key Technology. Aeronautical Manufacturing Technology, 2015(13): [32] Guo Hongjie,Du Baorui, Zhao Jianguo, et al. Key Technology on Intelligent Aircraft Assembly. Aeronautical Manufacturing Technology, 2014(21): [33] Yao Yanbin, Zou Fang, Liu Huadong. Intelligent Assembly Technology of Aircraft. Aeronautical Manufacturing Technology, 2014(22): [34] Zhu Haiping, Yang Fuming, He Jie. Key Technology of Aircraft Assembly Quality Management System and Its Implementation. Aeronautical Manufacturing Technology, 2015(9): [35] Mei Z, Maropoulos P G. Review of the application of flexible, measurement-assisted assembly technology in aircraft manufacturing. Proceedings of the Institution of Mechanical Engineers Part B Journal of Engineering Manufacture, 2014, 228(10): [36] Wu Xiao-feng, Yue Hong, Shi Yao, et al. Current status and development trend of smart manufacturing technology and standardization of China s shipbuilding industry. Shipence and Technology, 2016, 38(5):1-6.