The flexible satellite batch production line is a complex discrete production system with multiple cross-disciplinary fields and mixed serial parallel tasks.As the source of the satellite batch production line process...The flexible satellite batch production line is a complex discrete production system with multiple cross-disciplinary fields and mixed serial parallel tasks.As the source of the satellite batch production line process,the warehousing system has urgent needs such as uncertain production scale and rapid iteration and optimization of business processes.Therefore,the requirements and architecture of complex discrete warehousing systems such as flexible satellite batch production lines are studied.The physical system of intelligent equipment is abstracted as a digital model to form the underlying module,and a digital fusion framework of“business domain+middleware platform+intelligent equipment information model”is constructed.The granularity of microservice splitting is calculated based on the dynamic correlation relationship between user access instances and database table structures.The general warehousing functions of the platform are divided to achieve module customization,addition,and configuration.An open discrete warehousing system based on microservices is designed.Software architecture and design develop complex discrete warehousing systems based on the SpringCloud framework.This architecture achieves the decoupling of business logic and physical hardware,enhances the maintainability and scalability of the system,and greatly improves the system’s adaptability to different complex discrete warehousing business scenarios.展开更多
Based on the comparison of several methods of time series predicting, this paper points out that it is necessary to use dynamic neural network in modeling of complex production process. Because self feedback and mutua...Based on the comparison of several methods of time series predicting, this paper points out that it is necessary to use dynamic neural network in modeling of complex production process. Because self feedback and mutual feedback are adopted among nodes at the same layer in Elman network, it has stronger ability of dynamic approximation, and can describe any non linear dynamic system. After the structure and mathematical description being given, dynamic back propagation (BP) algorithm of training weights of Elman neural network is deduced. At last, the network is used to predict ash content of black amber in jigging production process. The results show that this neural network is powerful in predicting and suitable for modeling, predicting, and controling of complex production process.展开更多
In response to the complex composition,scattered data storage,and differences in management levels of manufacturing resources in the production site of complex products,the research and application of digital technolo...In response to the complex composition,scattered data storage,and differences in management levels of manufacturing resources in the production site of complex products,the research and application of digital technology for perception and control of manufacturing resources in the production site of complex products are of great significance for accelerating the digital transformation and upgrading of complex product manufacturing enterprises.Firstly,focusing on the problems of single element of local management,high cost of heterogeneous integration of multiple data sources,and the difficulty in cleaning up the global status of manufacturing resources in the production site of complex products,basic requirements and core requirements of enterprises for global management and control of manufacturing resources in the production site are deeply analyzed.Secondly,the indicators and data sources of different manufacturing resources that managers at different levels are concerned about are analyzed,providing guidance for refined management.Thirdly,a reference architecture of the manufacturing resource management and control platform for the production site of complex products is proposed,supporting access,integration,and global unified management of manufacturing resource information through the access strategy,data,basic component,and APP layers.Finally,the feasibility,effectiveness,and practicality of the architecture are verified through practical cases,aiming to provide a reference for the manufacturing resource management of complex product manufacturing enterprises.展开更多
Blockchain technology has attracted worldwide atten-tion,and has strong application potential in complex product system supply chain and other fields.This paper focuses on the supply chain management issues of complex...Blockchain technology has attracted worldwide atten-tion,and has strong application potential in complex product system supply chain and other fields.This paper focuses on the supply chain management issues of complex product systems,and combines the technical characteristics of blockchain,such as tamper resistance and strong resistance to destruction,to conduct research on the application of blockchain based supply chain management for complex product systems.The block-chain technology is integrated into functional modules such as business interaction,privacy protection,data storage,and sys-tem services.The application technology architecture of com-plex product system supply chain integrated with blockchain is constructed.The application practice in complex product sys-tem supply chain is carried out.The results show that the sup-ply chain of complex product systems has the functions of traceability,cost reduction,and anti-counterfeiting protection.Finally,the future development direction and research focus of the complex product system supply chain based on blockchain are prospected,which provides a reference for the equipment manufacturing supply chain management in the mili-tary industry.展开更多
Efficient preparation and assembly guidance for complex products relies heavily on semantic information in assembly process documents.This information encompasses various levels of elements and complex semantic relati...Efficient preparation and assembly guidance for complex products relies heavily on semantic information in assembly process documents.This information encompasses various levels of elements and complex semantic relationships.However,there is currently a scarcity of effective modeling techniques to express these documents'inherent assembly process knowledge.This study introduces a method for constructing an Assembly Process Knowledge Graph of Complex Products(APKG-CP)utilizing text mining techniques to tackle the challenges of high costs,low efficiency,and difficulty reusing process knowledge.Developing the assembly process knowledge graph involves categorizing entity and relationship classes from multiple levels.The Bert-BiLSTM-CRF model integrates BERT(bidirectional encoder representations from transformers),BiLSTM(bidirectional long short-term memory),and CRF(conditional random field)to extract knowledge entities and relationships in assembly process documents automatically.Furthermore,the knowledge fusion method automatically instantiates the assembly process knowledge graph.The proposed construction method is validated by constructing and visualizing an assembly process knowledge graph using data from an aerospace enterprise as an example.Integrating the knowledge graph with the assembly process preparation system demonstrates its effectiveness for process design.展开更多
Under the paradigm of Industry 5.0,intelligent manufacturing transcends mere efficiency enhancement by emphasizing human-machine collaboration,where human expertise plays a central role in assembly processes.Despite a...Under the paradigm of Industry 5.0,intelligent manufacturing transcends mere efficiency enhancement by emphasizing human-machine collaboration,where human expertise plays a central role in assembly processes.Despite advancements in intelligent and digital technologies,assembly process design still heavily relies on manual knowledge reuse,and inefficiencies and inconsistent quality in process documentation are caused.To address the aforementioned issues,this paper proposes a knowledge push method of complex product assembly process design based on distillation model-based dynamically enhanced graph and Bayesian network.First,an initial knowledge graph is constructed using a BERT-BiLSTM-CRF model trained with integrated human expertise and a fine-tuned large language model.Then,a confidence-based dynamic weighted fusion strategy is employed to achieve dynamic incremental construction of the knowledge graph with low resource consumption.Subsequently,a Bayesian network model is constructed based on the relationships between assembly components,assembly features,and operations.Bayesian network reasoning is used to push assembly process knowledge under different design requirements.Finally,the feasibility of the Bayesian network construction method and the effectiveness of Bayesian network reasoning are verified through a specific example,significantly improving the utilization of assembly process knowledge and the efficiency of assembly process design.展开更多
Heavy-duty machine tools are composed of many subsystems with different functions,and their reliability is governed by the reliabilities of these subsystems.It is important to rank the weaknesses of subsystems and ide...Heavy-duty machine tools are composed of many subsystems with different functions,and their reliability is governed by the reliabilities of these subsystems.It is important to rank the weaknesses of subsystems and identify the weakest subsystem to optimize products and improve their reliabilities.However,traditional ranking methods based on failure mode effect and critical analysis(FMECA)does not consider the complex maintenance of products.Herein,a weakness ranking method for the subsystems of heavy-duty machine tools is proposed based on generalized FMECA information.In this method,eight reliability indexes,including maintainability and maintenance cost,are considered in the generalized FMECA information.Subsequently,the cognition best worst method is used to calculate the weight of each screened index,and the weaknesses of the subsystems are ranked using a technique for order preference by similarity to an ideal solution.Finally,based on the failure data collected from certain domestic heavy-duty horizontal lathes,the weakness ranking result of the subsystems is obtained to verify the effectiveness of the proposed method.An improved weakness ranking method that can comprehensively analyze and identify weak subsystems is proposed herein for designing and improving the reliability of complex electromechanical products.展开更多
In the conceptual design stage of complex products, CBR（Case-Based Reasoning） tool is useful to offer a feasible set of schemes. Then the most adaptive scheme can be generated through a procedure of comparison and e...In the conceptual design stage of complex products, CBR（Case-Based Reasoning） tool is useful to offer a feasible set of schemes. Then the most adaptive scheme can be generated through a procedure of comparison and evaluation. The procedure is essentially a multiple criteria decision-making problem. The traditional multiple criteria programming is not flexible enough in executing the system evaluation algorithm due to both the limited experimental data and the lack of human experiences. To make the CBR tool to be more efficient, a new method for the best choice among the feasible schemes based on the Fuzzy AHP using Fuzzy numbers （FFAHP） is proposed. Since the final results become a problem of ranking the mean of fuzzy numbers by the optimism of decision-maker using the FFAHP, its execution is much more intuitive and effective than with the traditional method.展开更多
This paper puts forward a complex inner product averaging method for calculating normal form of ODE. Compared with conventional averaging method, the theoretic analytical process has such simple forms as to realize co...This paper puts forward a complex inner product averaging method for calculating normal form of ODE. Compared with conventional averaging method, the theoretic analytical process has such simple forms as to realize computer program easily. Results can be applied in both autonomous and non-autonomous systems. At last, an example is resolved to verify the method.展开更多
With the development of science and technology as well as the diversification and individualization of market demand,modern products update more and more rapidly.e rapid development of new products to satisfy the incr...With the development of science and technology as well as the diversification and individualization of market demand,modern products update more and more rapidly.e rapid development of new products to satisfy the increasingly improved and personalized customer demands greatly depends on the progress in the innovative design theory and performance optimization展开更多
Background Augmented assembly guidance aims to help users complete assembly operations more efficiently and quickly through augmented reality technology,breaking the limitations of traditional assembly guidance techno...Background Augmented assembly guidance aims to help users complete assembly operations more efficiently and quickly through augmented reality technology,breaking the limitations of traditional assembly guidance technology which is single in content and boring in way.Object registration is one of the key technologies in augmented assembly guidance process,which can affect the location and direction of virtual assembly guidance information in real assembly environment.Methods This paper presents an object registration method based on RGB-D camera,which combines Lucas-Kanade(LK)optical flow algorithm and Iterative Closet Point(ICP)algorithm.An augmented assembly guidance system for complex products through this method is built.Meanwhile,in order to compare the effectiveness of the proposed method,we also implemented object registration based on an open source augmented reality SDK Vuforia.Results An engine model and a complex weapon cabin equipment are taken as an case to verify this work.The result shows that the registration method proposed in this paper is more accurate and stable compared with that based on Vuforia and the augmented assembly guidance system through this method greatly improves the user's time compared with the traditional assembly.Conclusions Therefore,we can conclude that the object registration method mentioned in this paper can be well applied in the augmented assembly guidance system,which can do enhance the efficiency of assembly considerably.展开更多
In order to intensify market competition, manufacturing enterprises must improve their product innovation capability. It is difficult to integrate the system modeling, simulation and collaborative process management i...In order to intensify market competition, manufacturing enterprises must improve their product innovation capability. It is difficult to integrate the system modeling, simulation and collaborative process management in complex product development. A collaborative platform for complex product development based on multi-domain unified modeling and simulation is proposed in this paper. The architecture of the platform is firstly stated. The idea and realization of three key technologies, i.e. multi-domain modeling and simulation for complex product, knowledge management for product design and simulation, multi-domain collaborative mechanism, are emphasized. Finally, an industry case is given. The demonstration of the system shows that integration architecture is the effective infrastructure for multi-domain collaborative product development.展开更多
Simulation technique is an efficient approach to realize the planning and scheduling of manufacturing process of products. An appropriate and efficient manufacturing process model is the basis and key of manufacturing...Simulation technique is an efficient approach to realize the planning and scheduling of manufacturing process of products. An appropriate and efficient manufacturing process model is the basis and key of manufacturing process simulation. By analyzing the features of large-sized and complex products, a method of manufacturing process modeling based on activity network is presented and a mapping algorithm of translating BOM/BOP into the manufacturing process model is designed in detail.展开更多
Many catalysts were pcrpared by carbonization of ion exchange resin-PdCl_2 complexes at high temperature in nitrogen, hydrogen atmosphere. The rates for the hydrogenation of methyl acrylate and the amounts of Pd eluti...Many catalysts were pcrpared by carbonization of ion exchange resin-PdCl_2 complexes at high temperature in nitrogen, hydrogen atmosphere. The rates for the hydrogenation of methyl acrylate and the amounts of Pd elution of the carbonaceous products were measured and compared with those of commercial Pd/C catalyst. It indicates that the carbonaceous products are less active than Pd/C. However, the leaching of Pd from carbonaceous products is very small and much less than that from Pd/C.展开更多
With the increasing of complexity of complex mechatronic products, it is necessary to involve multidis- ciplinary design teams, thus, the traditional customer requirements modeling for a single discipline team becomes...With the increasing of complexity of complex mechatronic products, it is necessary to involve multidis- ciplinary design teams, thus, the traditional customer requirements modeling for a single discipline team becomes difficult to be applied in a multidisciplinary team and project since team members with various disciplinary backgrounds may have different interpretations of the customers＇ requirements. A new synthesized multidisci- plinary customer requirements modeling method is pro- vided for obtaining and describing the common understanding of customer requirements （CRs） and more importantly transferring them into a detailed and accurate product design specifications （PDS） to interact with dif- ferent team members effectively. A case study of designing a high speed train verifies the rationality and feasibility of the proposed multidisciplinary requirement modeling method for complex mechatronic product development. This proposed research offersthe instruction to realize the customer-driven personalized customization of complex mechatronic product.展开更多
Axiomatic design（AD） is a popular design method,and satisfying the independence axiom is the basis of AD.However,AD doesn＇t provide methods to decompose functions then keep them independent and to handle coupled de...Axiomatic design（AD） is a popular design method,and satisfying the independence axiom is the basis of AD.However,AD doesn＇t provide methods to decompose functions then keep them independent and to handle coupled design.A few of ways of handling coupled design are mainly passive resolutions when coupled design exists,but not efficient to each product design.Hence,this paper presents an innovative approach to design and decompose functions of complex products based on functional connections,aiming at actively avoiding functional coupling.By contrasting with component networks,four kinds of relations among functions are identified,including spatial,energy,material,and information connection.Then the definitions of these relations and the dominant connection are given.Based on the definitions,the principles of functional decomposition and design are developed,in which each non-leaf function is broken into sub functions centered on its dominant connection with avoidance of functional cross and coupling,and sequentially satisfies the independence axiom.Then the operational flow of the proposed approach is constructed.Determining the dominant connection of a function,decomposing the function into sub functions in terms of the dominant connection and reverse examination and optimization are planed as the core steps in each zigzagging.Input process output（IPO） analysis is introduced to obtain the dominant connection of a function,some rules for examining and optimizing the decomposition results reversely according to oriented object theory are presented as well.An illustrative example about the pouring function of squeeze casting equipments presented demonstrates how to use the proposed approach,and indicates its effectiveness.The proposed approach expands the principles of AD,constructs a guidance policy for independent functional design of complex products based on AD,and can help decrease or actively avoid coupled design and improve design efficiency.展开更多
When designing large-sized complex machinery products, the design focus is always on the overall per- formance; however, there exist no design theory and method based on performance driven. In view of the defi- ciency...When designing large-sized complex machinery products, the design focus is always on the overall per- formance; however, there exist no design theory and method based on performance driven. In view of the defi- ciency of the existing design theory, according to the performance features of complex mechanical products, the performance indices are introduced into the traditional design theory of ＂Requirement-Function-Structure＂ to construct a new five-domain design theory of ＂Client Requirement-Function-Performance-Structure-Design Parameter＂. To support design practice based on this new theory, a product data model is established by using per- formance indices and the mapping relationship between them and the other four domains. When the product data model is applied to high-speed train design and combining the existing research result and relevant standards, the corresponding data model and its structure involving five domains of high-speed trains are established, which can provide technical support for studying the relationships between typical performance indices and design parame- ters and the fast achievement of a high-speed train scheme design. The five domains provide a reference for the design specification and evaluation criteria of high speed train and a new idea for the train＇s parameter design.展开更多
Multi-disciplinary virtual prototypes of complex products are increasingly and widely used in modern advanced manufactur- ing. How to effectively address the problems of unified modeling, composition and reuse based o...Multi-disciplinary virtual prototypes of complex products are increasingly and widely used in modern advanced manufactur- ing. How to effectively address the problems of unified modeling, composition and reuse based on the multi-disciplinary heteroge- neous models has brought great challenges to the modeling and simulation （M＆S） science and technology. This paper presents a top-level modeling theory based on the meta modeling framework （M2F） of the COllaborative SIMulation （COSlM） theory of virtual prototyping to solve the problems. Firstly the fundamental prin- ciples of the top-level modeling theory are decribed to expound the premise, assumptions, basic conventions and special require- ments in the description of complex heterogeneous systems. Next the formalized definitions for each factor in top level modeling are proposed and the hierarchical nature of them is illustrated. After demonstrating that they are self-closing, this paper divides the top- level modeling into two views, static structural graph and dynamic behavioral graph. Finally, a case study is discussed to demon- strate the feasibility of the theory.展开更多
Changes in requirements may result in the increasing of product development project cost and lead time, therefore, it is important to understand how require- ment changes propagate in the design of complex product sys...Changes in requirements may result in the increasing of product development project cost and lead time, therefore, it is important to understand how require- ment changes propagate in the design of complex product systems and be able to select best options to guide design. Currently, a most approach for design change is lack of take the multi-disciplinary coupling relationships and the number of parameters into account integrally. A new design change model is presented to systematically analyze and search change propagation paths. Firstly, a PDS-Be- havior-Structure-based design change model is established to describe requirement changes causing the design change propagation in behavior and structure domains. Secondly, a multi-disciplinary oriented behavior matrix is utilized to support change propagation analysis of complex product systems, and the interaction relationships of the matrix elements are used to obtain an initial set of change paths. Finally, a rough set-based propagation space reducing tool is developed to assist in narrowing change propagation paths by computing the importance of the design change parameters. The proposed new design change model and its associated tools have been demonstrated by the scheduling change propagation paths of high speed train＇s bogie to show its feasibility and effectiveness. This model is not only supportive to response quickly to diversified market requirements, but also helpful to satisfy customer require- ments and reduce product development lead time. The proposed new design change model can be applied in a wide range of engineering systems design with improved efficiency.展开更多
文摘The flexible satellite batch production line is a complex discrete production system with multiple cross-disciplinary fields and mixed serial parallel tasks.As the source of the satellite batch production line process,the warehousing system has urgent needs such as uncertain production scale and rapid iteration and optimization of business processes.Therefore,the requirements and architecture of complex discrete warehousing systems such as flexible satellite batch production lines are studied.The physical system of intelligent equipment is abstracted as a digital model to form the underlying module,and a digital fusion framework of“business domain+middleware platform+intelligent equipment information model”is constructed.The granularity of microservice splitting is calculated based on the dynamic correlation relationship between user access instances and database table structures.The general warehousing functions of the platform are divided to achieve module customization,addition,and configuration.An open discrete warehousing system based on microservices is designed.Software architecture and design develop complex discrete warehousing systems based on the SpringCloud framework.This architecture achieves the decoupling of business logic and physical hardware,enhances the maintainability and scalability of the system,and greatly improves the system’s adaptability to different complex discrete warehousing business scenarios.
文摘Based on the comparison of several methods of time series predicting, this paper points out that it is necessary to use dynamic neural network in modeling of complex production process. Because self feedback and mutual feedback are adopted among nodes at the same layer in Elman network, it has stronger ability of dynamic approximation, and can describe any non linear dynamic system. After the structure and mathematical description being given, dynamic back propagation (BP) algorithm of training weights of Elman neural network is deduced. At last, the network is used to predict ash content of black amber in jigging production process. The results show that this neural network is powerful in predicting and suitable for modeling, predicting, and controling of complex production process.
文摘In response to the complex composition,scattered data storage,and differences in management levels of manufacturing resources in the production site of complex products,the research and application of digital technology for perception and control of manufacturing resources in the production site of complex products are of great significance for accelerating the digital transformation and upgrading of complex product manufacturing enterprises.Firstly,focusing on the problems of single element of local management,high cost of heterogeneous integration of multiple data sources,and the difficulty in cleaning up the global status of manufacturing resources in the production site of complex products,basic requirements and core requirements of enterprises for global management and control of manufacturing resources in the production site are deeply analyzed.Secondly,the indicators and data sources of different manufacturing resources that managers at different levels are concerned about are analyzed,providing guidance for refined management.Thirdly,a reference architecture of the manufacturing resource management and control platform for the production site of complex products is proposed,supporting access,integration,and global unified management of manufacturing resource information through the access strategy,data,basic component,and APP layers.Finally,the feasibility,effectiveness,and practicality of the architecture are verified through practical cases,aiming to provide a reference for the manufacturing resource management of complex product manufacturing enterprises.
基金supported by the National Natural Science Foundation of China(71871007)Project of Chinese Academy of Engineering.
文摘Blockchain technology has attracted worldwide atten-tion,and has strong application potential in complex product system supply chain and other fields.This paper focuses on the supply chain management issues of complex product systems,and combines the technical characteristics of blockchain,such as tamper resistance and strong resistance to destruction,to conduct research on the application of blockchain based supply chain management for complex product systems.The block-chain technology is integrated into functional modules such as business interaction,privacy protection,data storage,and sys-tem services.The application technology architecture of com-plex product system supply chain integrated with blockchain is constructed.The application practice in complex product sys-tem supply chain is carried out.The results show that the sup-ply chain of complex product systems has the functions of traceability,cost reduction,and anti-counterfeiting protection.Finally,the future development direction and research focus of the complex product system supply chain based on blockchain are prospected,which provides a reference for the equipment manufacturing supply chain management in the mili-tary industry.
基金Supported by National Natural Science Foundation of China(Grant No.52375479)。
文摘Efficient preparation and assembly guidance for complex products relies heavily on semantic information in assembly process documents.This information encompasses various levels of elements and complex semantic relationships.However,there is currently a scarcity of effective modeling techniques to express these documents'inherent assembly process knowledge.This study introduces a method for constructing an Assembly Process Knowledge Graph of Complex Products(APKG-CP)utilizing text mining techniques to tackle the challenges of high costs,low efficiency,and difficulty reusing process knowledge.Developing the assembly process knowledge graph involves categorizing entity and relationship classes from multiple levels.The Bert-BiLSTM-CRF model integrates BERT(bidirectional encoder representations from transformers),BiLSTM(bidirectional long short-term memory),and CRF(conditional random field)to extract knowledge entities and relationships in assembly process documents automatically.Furthermore,the knowledge fusion method automatically instantiates the assembly process knowledge graph.The proposed construction method is validated by constructing and visualizing an assembly process knowledge graph using data from an aerospace enterprise as an example.Integrating the knowledge graph with the assembly process preparation system demonstrates its effectiveness for process design.
基金Supported by National Key Research and Development Program(Grant No.2024YFB3312700)National Natural Science Foundation of China(Grant No.52405541)the Changzhou Municipal Sci&Tech Program(Grant No.CJ20241131)。
文摘Under the paradigm of Industry 5.0,intelligent manufacturing transcends mere efficiency enhancement by emphasizing human-machine collaboration,where human expertise plays a central role in assembly processes.Despite advancements in intelligent and digital technologies,assembly process design still heavily relies on manual knowledge reuse,and inefficiencies and inconsistent quality in process documentation are caused.To address the aforementioned issues,this paper proposes a knowledge push method of complex product assembly process design based on distillation model-based dynamically enhanced graph and Bayesian network.First,an initial knowledge graph is constructed using a BERT-BiLSTM-CRF model trained with integrated human expertise and a fine-tuned large language model.Then,a confidence-based dynamic weighted fusion strategy is employed to achieve dynamic incremental construction of the knowledge graph with low resource consumption.Subsequently,a Bayesian network model is constructed based on the relationships between assembly components,assembly features,and operations.Bayesian network reasoning is used to push assembly process knowledge under different design requirements.Finally,the feasibility of the Bayesian network construction method and the effectiveness of Bayesian network reasoning are verified through a specific example,significantly improving the utilization of assembly process knowledge and the efficiency of assembly process design.
基金Supported by National Nat ural Science Foundation of China(Grant Nos.51675227,51975249)Jilin Province Science and Technology Development Funds(Grant Nos.20180201007GX,20190302017GX)+2 种基金Technology Development and Research of Jilin Province(Grant No.2019C037-01)Changchun Science and Technology Planning Project(Grant No.19SS011)National Science and technology Major Project(Grant No.2014ZX04015031).
文摘Heavy-duty machine tools are composed of many subsystems with different functions,and their reliability is governed by the reliabilities of these subsystems.It is important to rank the weaknesses of subsystems and identify the weakest subsystem to optimize products and improve their reliabilities.However,traditional ranking methods based on failure mode effect and critical analysis(FMECA)does not consider the complex maintenance of products.Herein,a weakness ranking method for the subsystems of heavy-duty machine tools is proposed based on generalized FMECA information.In this method,eight reliability indexes,including maintainability and maintenance cost,are considered in the generalized FMECA information.Subsequently,the cognition best worst method is used to calculate the weight of each screened index,and the weaknesses of the subsystems are ranked using a technique for order preference by similarity to an ideal solution.Finally,based on the failure data collected from certain domestic heavy-duty horizontal lathes,the weakness ranking result of the subsystems is obtained to verify the effectiveness of the proposed method.An improved weakness ranking method that can comprehensively analyze and identify weak subsystems is proposed herein for designing and improving the reliability of complex electromechanical products.
基金This project was partly supported bythe Key Programof the National Natural Science Foundation of China (79990580) .
文摘In the conceptual design stage of complex products, CBR（Case-Based Reasoning） tool is useful to offer a feasible set of schemes. Then the most adaptive scheme can be generated through a procedure of comparison and evaluation. The procedure is essentially a multiple criteria decision-making problem. The traditional multiple criteria programming is not flexible enough in executing the system evaluation algorithm due to both the limited experimental data and the lack of human experiences. To make the CBR tool to be more efficient, a new method for the best choice among the feasible schemes based on the Fuzzy AHP using Fuzzy numbers （FFAHP） is proposed. Since the final results become a problem of ranking the mean of fuzzy numbers by the optimism of decision-maker using the FFAHP, its execution is much more intuitive and effective than with the traditional method.
文摘This paper puts forward a complex inner product averaging method for calculating normal form of ODE. Compared with conventional averaging method, the theoretic analytical process has such simple forms as to realize computer program easily. Results can be applied in both autonomous and non-autonomous systems. At last, an example is resolved to verify the method.
文摘With the development of science and technology as well as the diversification and individualization of market demand,modern products update more and more rapidly.e rapid development of new products to satisfy the increasingly improved and personalized customer demands greatly depends on the progress in the innovative design theory and performance optimization
基金the National Defense Basic Scientific Research,China(JCKY2016605B006)National Defense Basic Scientific Research,China(JCKY2017203B071).
文摘Background Augmented assembly guidance aims to help users complete assembly operations more efficiently and quickly through augmented reality technology,breaking the limitations of traditional assembly guidance technology which is single in content and boring in way.Object registration is one of the key technologies in augmented assembly guidance process,which can affect the location and direction of virtual assembly guidance information in real assembly environment.Methods This paper presents an object registration method based on RGB-D camera,which combines Lucas-Kanade(LK)optical flow algorithm and Iterative Closet Point(ICP)algorithm.An augmented assembly guidance system for complex products through this method is built.Meanwhile,in order to compare the effectiveness of the proposed method,we also implemented object registration based on an open source augmented reality SDK Vuforia.Results An engine model and a complex weapon cabin equipment are taken as an case to verify this work.The result shows that the registration method proposed in this paper is more accurate and stable compared with that based on Vuforia and the augmented assembly guidance system through this method greatly improves the user's time compared with the traditional assembly.Conclusions Therefore,we can conclude that the object registration method mentioned in this paper can be well applied in the augmented assembly guidance system,which can do enhance the efficiency of assembly considerably.
基金Supported by the National Natural Science Foundation of China (60736019)the National High Technology Research and Development Program of China (863 Program) (2007AA40603)
文摘In order to intensify market competition, manufacturing enterprises must improve their product innovation capability. It is difficult to integrate the system modeling, simulation and collaborative process management in complex product development. A collaborative platform for complex product development based on multi-domain unified modeling and simulation is proposed in this paper. The architecture of the platform is firstly stated. The idea and realization of three key technologies, i.e. multi-domain modeling and simulation for complex product, knowledge management for product design and simulation, multi-domain collaborative mechanism, are emphasized. Finally, an industry case is given. The demonstration of the system shows that integration architecture is the effective infrastructure for multi-domain collaborative product development.
文摘Simulation technique is an efficient approach to realize the planning and scheduling of manufacturing process of products. An appropriate and efficient manufacturing process model is the basis and key of manufacturing process simulation. By analyzing the features of large-sized and complex products, a method of manufacturing process modeling based on activity network is presented and a mapping algorithm of translating BOM/BOP into the manufacturing process model is designed in detail.
文摘Many catalysts were pcrpared by carbonization of ion exchange resin-PdCl_2 complexes at high temperature in nitrogen, hydrogen atmosphere. The rates for the hydrogenation of methyl acrylate and the amounts of Pd elution of the carbonaceous products were measured and compared with those of commercial Pd/C catalyst. It indicates that the carbonaceous products are less active than Pd/C. However, the leaching of Pd from carbonaceous products is very small and much less than that from Pd/C.
基金Supported by Open Outreach Project of A New Biomimicry and Crowdsourcing Based Digital Design Platform for High Speed Train from State Key Laboratory of Traction PowerNational Natural Science Foundation of China(Grant No.51575461)
文摘With the increasing of complexity of complex mechatronic products, it is necessary to involve multidis- ciplinary design teams, thus, the traditional customer requirements modeling for a single discipline team becomes difficult to be applied in a multidisciplinary team and project since team members with various disciplinary backgrounds may have different interpretations of the customers＇ requirements. A new synthesized multidisci- plinary customer requirements modeling method is pro- vided for obtaining and describing the common understanding of customer requirements （CRs） and more importantly transferring them into a detailed and accurate product design specifications （PDS） to interact with dif- ferent team members effectively. A case study of designing a high speed train verifies the rationality and feasibility of the proposed multidisciplinary requirement modeling method for complex mechatronic product development. This proposed research offersthe instruction to realize the customer-driven personalized customization of complex mechatronic product.
基金supported by Guangdong Provincial & Ministry of Education IAR Project of China (Grant No. 2009A090100026)Guangxi Provincial Science and Technology Infrastructure Construction Project of China (Grant No. Guikeneng 0842006,09-007-05)
文摘Axiomatic design（AD） is a popular design method,and satisfying the independence axiom is the basis of AD.However,AD doesn＇t provide methods to decompose functions then keep them independent and to handle coupled design.A few of ways of handling coupled design are mainly passive resolutions when coupled design exists,but not efficient to each product design.Hence,this paper presents an innovative approach to design and decompose functions of complex products based on functional connections,aiming at actively avoiding functional coupling.By contrasting with component networks,four kinds of relations among functions are identified,including spatial,energy,material,and information connection.Then the definitions of these relations and the dominant connection are given.Based on the definitions,the principles of functional decomposition and design are developed,in which each non-leaf function is broken into sub functions centered on its dominant connection with avoidance of functional cross and coupling,and sequentially satisfies the independence axiom.Then the operational flow of the proposed approach is constructed.Determining the dominant connection of a function,decomposing the function into sub functions in terms of the dominant connection and reverse examination and optimization are planed as the core steps in each zigzagging.Input process output（IPO） analysis is introduced to obtain the dominant connection of a function,some rules for examining and optimizing the decomposition results reversely according to oriented object theory are presented as well.An illustrative example about the pouring function of squeeze casting equipments presented demonstrates how to use the proposed approach,and indicates its effectiveness.The proposed approach expands the principles of AD,constructs a guidance policy for independent functional design of complex products based on AD,and can help decrease or actively avoid coupled design and improve design efficiency.
基金Supported by National Natural Science Foundation of China(Grant Nos.51275432,51505390)Sichuan Application Foundation Projects(Grant No.2016JY0098)Independent Research Project of TPL(Grant No.TPL1501)
文摘When designing large-sized complex machinery products, the design focus is always on the overall per- formance; however, there exist no design theory and method based on performance driven. In view of the defi- ciency of the existing design theory, according to the performance features of complex mechanical products, the performance indices are introduced into the traditional design theory of ＂Requirement-Function-Structure＂ to construct a new five-domain design theory of ＂Client Requirement-Function-Performance-Structure-Design Parameter＂. To support design practice based on this new theory, a product data model is established by using per- formance indices and the mapping relationship between them and the other four domains. When the product data model is applied to high-speed train design and combining the existing research result and relevant standards, the corresponding data model and its structure involving five domains of high-speed trains are established, which can provide technical support for studying the relationships between typical performance indices and design parame- ters and the fast achievement of a high-speed train scheme design. The five domains provide a reference for the design specification and evaluation criteria of high speed train and a new idea for the train＇s parameter design.
基金supported by the National High Technology Research and Development Program (863 Program) (2011AA040502).
文摘Multi-disciplinary virtual prototypes of complex products are increasingly and widely used in modern advanced manufactur- ing. How to effectively address the problems of unified modeling, composition and reuse based on the multi-disciplinary heteroge- neous models has brought great challenges to the modeling and simulation （M＆S） science and technology. This paper presents a top-level modeling theory based on the meta modeling framework （M2F） of the COllaborative SIMulation （COSlM） theory of virtual prototyping to solve the problems. Firstly the fundamental prin- ciples of the top-level modeling theory are decribed to expound the premise, assumptions, basic conventions and special require- ments in the description of complex heterogeneous systems. Next the formalized definitions for each factor in top level modeling are proposed and the hierarchical nature of them is illustrated. After demonstrating that they are self-closing, this paper divides the top- level modeling into two views, static structural graph and dynamic behavioral graph. Finally, a case study is discussed to demon- strate the feasibility of the theory.
基金Supported by National Natural Science Foundation of China(Grant Nos.51305367,51575461)Doctoral Student Innovation Funds for Hai-Zhu Zhang from Southwest Jiaotong University,China
文摘Changes in requirements may result in the increasing of product development project cost and lead time, therefore, it is important to understand how require- ment changes propagate in the design of complex product systems and be able to select best options to guide design. Currently, a most approach for design change is lack of take the multi-disciplinary coupling relationships and the number of parameters into account integrally. A new design change model is presented to systematically analyze and search change propagation paths. Firstly, a PDS-Be- havior-Structure-based design change model is established to describe requirement changes causing the design change propagation in behavior and structure domains. Secondly, a multi-disciplinary oriented behavior matrix is utilized to support change propagation analysis of complex product systems, and the interaction relationships of the matrix elements are used to obtain an initial set of change paths. Finally, a rough set-based propagation space reducing tool is developed to assist in narrowing change propagation paths by computing the importance of the design change parameters. The proposed new design change model and its associated tools have been demonstrated by the scheduling change propagation paths of high speed train＇s bogie to show its feasibility and effectiveness. This model is not only supportive to response quickly to diversified market requirements, but also helpful to satisfy customer require- ments and reduce product development lead time. The proposed new design change model can be applied in a wide range of engineering systems design with improved efficiency.
