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The purpose of this paper is to propose a three-dimensional (3D) assembly model retrieval method based on assembling semantic information to address semantic mismatches, poor accuracy and low efficiency in existing 3D assembly model retrieval methods.

The paper proposes an assembly model retrieval method. First, assembly information retrieval is performed, and 3D models that conform to the design intention of the assembly are found by retrieving the code. On this basis, because there are conjugate subgraphs between attributed adjacency graphs (AAG) that have an assembly relationship, the assembly model geometric retrieval is translated into a problem of finding AAGs with a conjugate subgraph. Finally, the frequent subgraph mining method is used to retrieve AAGs with conjugate subgraphs.

The method improved the efficiency and accuracy of assembly model retrieval.

The examples illustrate the specific retrieval process and verify the feasibility and reasonability of the assembly model retrieval method in practical applications.

The assembly model retrieval method in the paper is an original method. Compared with other methods, good results were obtained.

The purpose of this paper is to define an approach to extract the liaison graph from a 3D CAD model and analyze a method to find at least a feasible assembly sequence for the product. The method could be useful to search the optimal sequence of assembling for a product, by comparing different sequences extracted in automatic mode from a 3D CAD model.

The method proposed analyzes the liaison graph extracted, in order to obtain the possible assembly sequences for the product under study. The extraction of the sequences is based on some attributes and parameters of the graph.

By means of the method proposed it is possible to obtain in automatic mode the liaison graph of an assembly 3D CAD model. Moreover, the study of the graph obtained allows the definition of all the assembly sequences for the product. Finally, it is possible to analyse the sequences found to select the optimal sequence.

The major limitation of the approach is, actually, the great number of impossible sequences that are extracted. For this, a little intervention by the user is required.

The application of the method allows the manufacturer to analyze and study the optimal assembly sequence without the direct use of a CAD system. The approach could be used at the early stage of the design process and by means of the database of the PDM/PLM systems.

The approach proposed in the paper is an original method to extract a liaison graph from a 3D CAD model. The approach to extract the assembly sequences was compared with other methods and good results have been obtained.

Fixture design is a complicated task requiring both intensive knowledge and experience. This paper aims to present a computer-aided fixture design (CAFD) system framework based on design reuse technology.

Fixture design domain ontology is constructed by analyzing fixture design document corpus. A design reuse engine is proposed to realize fixture design knowledge retrieval and fixture model retrieval based on ontology and find fixture design cases similar to fixture design problem, and then use evolutionary methods to modify the retrieved model to meet the design requirements and then generate a new fixture.

The paper finds that the proposed framework is an efficient tool to improve efficiency of fixture design.

Fixture design existing experience and cases can be used efficiently reused and to advance new fixture design processes.

This paper presents a CAFD system framework capable of carrying out fixture design through full using of the existing fixture design resource and experienced knowledge.

The purpose of this paper is to find a method for key assembly structure identification in complex mechanical assembly. Three-dimensional model reuse plays an increasingly important role in complex product design and innovative design. Assembly model has become important resource of models reuse in enterprises, which contains certain function assembly structures. These assembly structures implicating plenty of design intent and design experience knowledge can be used to support function-structure design, modular design reuse and semantics analysis for complex product.

A method for identifying key assembly structures in assembly model is presented from the viewpoint of assembly topology and multi-source attributes. First, assembly model is represented based on complex network. Then, a two-level evaluation model is put forward to evaluate importance of parts assembled, and the key function parts in assembly can be obtained. After that, on the basis of the function parts, a heuristic algorithm upon breadth first searching is given to identify key assembly structures.

The method could be used to evaluate key function parts and identify key assembly structures in complex mechanical assembly according to the specific circumstances.

The method can not only help designers find the key assembly structure in complex mechanical assembly model, facilitate the function-structure designing and semantics analyzing, and thereby improve the efficiency of product knowledge reuse, but also assist in analyzing influence scope of key function part changing and optimization of the assembly process for complex mechanical assembly.

The paper is the first to propose a method for key assembly structure identification in complex mechanical assembly, where the key function parts can be evaluated through a two-level evaluation model, and the key assembly structures are identified automatically based on complex network.

The purpose of this study is the use of 3D printing technology to perform maintenance on damaged parts on site. To maintain damaged parts, the user needs experience in the parts design and 3D printing technology. To help users who have little or no experience on 3D printing, a part library-based information retrieval and inspection framework was proposed to support the process of manufacturing replaceable parts using a 3D printer.

To establish the framework, 3D printing-based maintenance procedure was first defined, comprising retrieval, manufacturing and inspection steps, while identifying the technical components required to perform the procedure. Once the technical components are identified, part library-based information retrieval and inspection framework was defined based on the technical components and the relationships between the components. For validation of the concept of the framework, prototype system is developed according to the proposed framework.

The feasibility of the proposed framework is proved through maintenance experiments on gaskets and O-rings.

The main contribution of this study is the proposal of the framework, which aims to support the maintenance of damaged parts for the user who has little or no experience in part design or does not know how to operate a 3D printer.

Complex mechanical 3D computer-aided design (CAD) model embodies rich implicit design knowledge. Through discovering the key function parts and key function module in 3D CAD assembly model in advance, it can promote the designers’ understanding and reuse efficiency of 3D assembly model in design reuse.

An approach for discovering key function module in complex mechanical 3D CAD assembly model is proposed. First, assembly network for 3D CAD assembly model is constructed, where the topology structure characteristics of 3D assembly model are analyzed based on complex network centrality. The degree centrality, closeness centrality, betweenness centrality and mutual information of node are used to evaluate the importance of the parts in 3D assembly model. Then, a multi-attribute decision model for part-node importance is established, and the comprehensive evaluation for key function parts in 3D assembly model is accomplished by combining Analytic Hierarchy Process and Technique for Order Preference by Similarity to an Ideal Solution (TOPSIS). Subsequently, a community discovery of function module in assembly model-based Clauset–Newman–Moore (CNM)-Centrality is given in details. Finally, 3D CAD assembly model of worm gear reducer is taken as an example to verify the effectiveness and feasibility of proposed method.

The key function part in CAD assembly model is evaluated comprehensively considering assembly topology more objectively. In addition, the key function module containing key function part is discovered from CAD assembly model by using CNM-Centrality-based community discovery.

The approach can be used for discovering important design knowledge from complex CAD assembly model when reusing the assembly model. It can help designers capture and understand the design thinking and intent, improve the reuse efficiency and quality.

The paper first proposes an approach for discovering key function module in complex mechanical 3D CAD assembly model taking advantage of complex network theory, where the key function part is evaluated using node centrality and TOPSIS, and the key function module is identified based on community discovery.

Design is a time-consuming process for mechanical production. Some design structures frequently occur in different products and can be shared by multiple assembly models. Thus, identifying these structures and adding them to a design knowledge library significantly speed up the design process. Most studies addressing this issue have traditionally focused on part models and have not extended to assembly models. This paper aims to find a method for common design structure discovery in assembly models.

Computer-aided design models have a great deal of valuable information defined by different designers in the design stages, especially the assembly models, which are actually carriers of information from multiple sources. In this paper, an approach for discovering a common design structure in assembly models is proposed by comparing information from multiple sources. Assembly models are first represented as attribute connection graphs (ACGs), in which we mainly consider topological information and various attributes of parts and connections. Then, we apply a K-means clustering method based on a similarity analysis of different attributes to classify the parts and connections and transform ACGs of assemblies into type code graphs (TCGs). After this, a discovery algorithm that improves upon fast frequent subgraph mining is used to identify common design structures in assemblies.

A new method was developed for discovering common design structures in assembly models, considering the similarity of information from multiple sources and allowing some differences in the details to keep both commonalities and individualities of common design structures.

Experiments show that the proposed method is efficient and can produce a reasonable result.

This discovery method helps designers find common design structures from different assembly models and shorten the design cycle. It is an effective approach to build a knowledge library for product design that can shorten the design cycle.

Three-dimensional computer-aided design (CAD) assembly model has become important resource for design reuse in enterprises, which implicates plenty of design intent, assembly intent, design experience knowledge and functional structures. To acquire quickly CAD assembly models associated with specific functions by using product function requirement information in the product conceptual design phase for model reuse, this paper aims to find an approach for structure-function correlations analysis and functional semantic annotation of mechanical CAD assembly model before functional semantic-based assembly retrieval.

An approach for structure-function correlations analysis and functional semantic annotation of CAD assembly model is proposed. First, the product knowledge model is constructed based on ontology including design knowledge and function knowledge. Then, CAD assembly model is represented by part attributed adjacency graph and partitioned into multiple functional regions. Assembly region and flow-activity region are defined for structure-function correlations analysis of CAD assembly model. Meanwhile, the extraction process of assembly region and flow-activity region is given in detail. Furthermore, structure-function correlations analysis and functional semantic annotation are achieved by considering comprehensively assembly structure and assembled part shape structure in CAD assembly model. After that, a structure-function relation model is established based on polychromatic sets for expressing explicitly and formally relationships between functional structures, assembled parts and functional semantics.

The correlation between structure and function is analyzed effectively, and functional semantics corresponding to structures in CAD assembly model are labeled. Additionally, the relationships between functional structures, assembled parts and functional semantics can be described explicitly and formally.

The approach can be used to help designers accomplish functional semantic annotation of CAD assembly models in model repository, which provides support for functional semantic-based CAD assembly retrieval in the product conceptual design phase. These assembly models can be reused for product structure design and assembly process design.

The paper proposes a novel approach for structure-function correlations analysis and functional semantic annotation of mechanical CAD assembly model. Functional structures in assembly model are extracted and analyzed from the point of view of assembly structure and function part structure. Furthermore, the correlation relation between structures, assembled parts and functional semantics is expressed explicitly and formally based on polychromatic sets.

A fixture is a special tool used to accurately and stably locate the workpiece during machining process. Proper fixture design improves the quality and production of parts and also facilitates the interchangeability of parts, which is prevalent in much of modern manufacturing. The purpose of this paper is to combine the rule‐based reasoning (RBR) and case‐based reasoning (CBR) method for machining fixture design in a virtual reality (VR) based integrated system.

In this paper, an approach combining the RBR and fuzzy comprehensive judgment method is proposed for reasoning suitable locating features and clamping features. Based on the reasoning results, a CBR method for machining fixture design is then presented.

The paper finds that the proposed system is an efficient tool for machining fixture design.

The proposed system enables the designers to perform fixture design with automated fixture locating method reasoning and make a new fixturing solution quickly by referencing previous design cases.

A VR application for machining fixture design is presented.

This paper aims to apply the augmented reality (AR) technology to assembly design in the early design stage. A proof‐of‐concept system with AR interface is developed.

Through AR interface, designers can design the assembly on the real assembly platform. The system helps users to design the assembly features to provide proper part‐part constraints in the early design stage. The virtual assembly features are rendered on the real assembly platform using AR registration techniques. The new evaluated assembly parts can be generated in the AR interface and assembled to assembly platform through assembly features. The model‐based collision detection technique is implemented for assembly constraint evaluation.

With AR interface, it would be possible to combine some of the benefits of both physical and virtual prototyping (VP). The AR environment can save a lot of computation resource compared to a totally virtual environment. Working on real assembly platform, designers have more realistic feel and the ability to design an assembly in a more intuitive way.

More interaction tools need to be developed to support the complex assembly design efficiently.

The presented system encourages designers to consider the assembly issues in the early design stage. The primitive 3D models of assembly parts with proper part‐part constraints are generated using the system before doing detailed geometry design.

A new markerless registration approach for AR system is presented. This generic approach can be also used for other AR applications.