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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.

Assembly sequence planning (ASP) is a crucial job during assembly process design. However, it is still difficult to reuse the existing solution to solve a new ASP problem. In particular, with the rapid development of digital technologies, the reusable assembly information of an existing solution is not concentrated in one multimedia but dispersed in multiple heterogeneous multimedia, e.g. text, three-dimensional graphics, even images and videos. This paper aims to propose a multimedia case (MC)-based reasoning framework to solve ASP by reusing the existing solution whose assembly information is dispersed in multimedia.

The proposed framework is designed with the introduction of the MC. An MC seamlessly integrates the dispersed assembly information of an existing solution. Under the proposed concept and architecture, the assembly information of an existing solution is extracted to build assembly descriptors of multimedia. Therefore, the MC is captured by organizing the assembly descriptors of corresponding multimedia.

By means of the framework proposed, it is possible to reuse the existing solution whose assembly information is dispersed in multimedia to solve ASP. Moreover, the extraction method of assembly information can flexibly parse most of the multimedia. Finally, the MC has the capability to represent the existing solution by collecting dispersed assembly information.

The proposed framework can discover the similar existing solution and avoid the potential failures confronted in the past so that the feasibility of ASP result can be improved as much as possible.

The purpose of this research is to investigate a new approach with its supporting building information modelling (BIM) + augmented reality (AR) tool to enhance architectural visualisation in building life cycle. Traditional approaches to visualise architectural design concentrate on static pictures or three-dimensional (3D) scale models which cause problems, such as expensive design evolution, lack of stakeholders’ communication and limited reusability. The 3D animated fly-throughs still occur on a computer screen in two-dimensions and seem cold and mechanical, unless done with advanced production software.

The method of this research included case study and interview. It was, first, stated, from the building process perspective, how the BIM + AR for Architectural Visualisation System (BAAVS) was realised by integrating two types of visualisation techniques: BIM and AR, and four stages of building life cycle. Then the paper demonstrated four case studies to validate the BAAVS. Finally, four interviews were made with each case manager and team members to collect feedback on utilising BAAVS technology. Questions were asked in the areas of benefits, drawbacks and technical limitations with respect to BAAVS.

Feedback from the stakeholders involved in the four cases indicated that BAAVS was useful and efficient to visualise architectural design and communicate with each other.

This paper demonstrates BAAVS that integrated BIM and AR into architectural visualisation. The system supports an innovative performance that allows: designers to put virtual building scheme in physical environment; owners to gain an immersive and interactive experience; and property sellers to communicate with customers efficiently.

The purpose of this paper is to focus on the characterization and classification of parts with respect to the meshing issue, and notably the meshing of thin parts difficulty handled automatically and which often requires adaptation steps. The objective is to distinguish the so-called thin parts and parts with thin features from the other parts.

The concepts of thin part and part with thin features are introduced together with the mechanisms and criteria used for their identification in a CAD models database. The criteria are built on top of a set of shape descriptors and notably the distance distribution which is used to characterize the thickness of the object. To speed up the identification process, shape descriptors are computed from tessellated parts.

A complete modular approach has been designed. It computes shape descriptors over parts stored in a directory and it uses criteria to distinguish three categories: thin parts, parts with thin features and other parts. Being the three categories identified, the user can spend more time on the parts that are considered as more difficulty meshable.

The approach is limited to the three above mentioned categories. However, it has been designed so that the values corresponding to the shape descriptors and associated meshing qualities can easily be inserted within a machining learning tool later on.

The use of the developed tool can be seen as a pre-processing step during the preparation of finite element (FE) simulation models. It is automatic and can be run in batch and in parallel.

The approach is modular, it is simple and easy to implement. Categories are built on top of several shape descriptors and not on a unique signature. It is independent of the CAD modeler. This approach is integrated within a FE simulation model preparation framework and help engineers anticipating difficulties when meshing CAD models.

The purpose of this paper is to provide a knowledge-enabled digital twin for smart design (KDT-SD) of aircraft assembly line (AAL) to enhance the AAL efficiency, performance and visibility. Modern AALs usually need to have capabilities such as digital-physical interaction and self-evaluation that brings significant challenges to traditional design method for AAL. The digital twin (DT) combining with reusable knowledge, as the key technologies in this framework, is introduced to promote the design process by configuring, understanding and evaluating design scheme.

The proposed KDT-SD framework is designed with the introduction of DT and knowledge. First, dynamic design knowledge library (DDK-Lib) is established which could support the various activities of DT in the entire design process. Then, the knowledge-driven digital AAL modeling method is proposed. At last, knowledge-based smart evaluation is used to understand and identify the design flaws, which could further improvement of the design scheme.

By means of the KDT-SD framework proposed, it is possible to apply DT to reduce the complexity and discover design flaws in AAL design. Moreover, the knowledge equips DT with the capacities of rapid modeling and smart evaluation that improve design efficiency and quality.

The proposed KDT-SD framework can provide efficient design of AAL and evaluate the design performance in advance so that the feasibility of design scheme can be improved as much as possible.

This paper introduces a schema for the product assembly feature data in an object-oriented and module-based format using Unified Modeling Language (UML). To link production with product design, it is essential to determine at an early stage which entities of product design and development are involved and used at the automated assembly planning and operations. To this end, it is absolutely reasonable to assign meaningful attributes to the parts’ design entities (assembly features) in a systematic and structured way. As such, this approach empowers processes such as motion planning and sequence planning in assembly design.

The assembly feature data requirements are studied and definitions are analyzed and redefined. Using object-oriented techniques, the assembly feature data structure and relationships are modeled based on the identified requirements as five UML packages (Part, three-dimensional (3D) models, Mating, Joint and Handling). All geometric and non-geometric design data entities endorsed with assembly design perspective are extracted or assigned from 3D models and realized through the featured entity interface class. The featured entities are then associated (used) with the mating, handling and joints features. The AssemblyFeature interface is realized through mating, handling and joint packages related to the assembly and part classes. Each package contains all relevant classes which further classify the important attributes of the main class.

This paper sets out to provide an explanatory approach using object-oriented techniques to model the schema of assembly features association and artifacts at the product design level, all of which are essential in several subsequent and parallel steps of the assembly planning process, as well as assembly feature entity assignments in design improvement cycle.

The practical implication based on the identified advantages can be classified in three main features: module-based design, comprehensive classification, integration. These features help the automation and solution development processes based on the proposed models much easier and systematic.

The proposed schema’s comprehensiveness and reliability are verified through comparisons with other works and the advantages are discussed in detail.

This paper aims to propose a robust method for non-rigid point set registration, using the Gaussian mixture model and accommodating non-rigid transformations. The posterior probabilities of the mixture model are determined through the proposed integrated feature divergence.

The method involves an alternating two-step framework, comprising correspondence estimation and subsequent transformation updating. For correspondence estimation, integrated feature divergences including both global and local features, are coupled with deterministic annealing to address the non-convexity problem of registration. For transformation updating, the expectation-maximization iteration scheme is introduced to iteratively refine correspondence and transformation estimation until convergence.

The experiments confirm that the proposed registration approach exhibits remarkable robustness on deformation, noise, outliers and occlusion for both 2D and 3D point clouds. Furthermore, the proposed method outperforms existing analogous algorithms in terms of time complexity. Application of stabilizing and securing intermodal containers loaded on ships is performed. The results demonstrate that the proposed registration framework exhibits excellent adaptability for real-scan point clouds, and achieves comparatively superior alignments in a shorter time.

The integrated feature divergence, involving both global and local information of points, is proven to be an effective indicator for measuring the reliability of point correspondences. This inclusion prevents premature convergence, resulting in more robust registration results for our proposed method. Simultaneously, the total operating time is reduced due to a lower number of iterations.

This paper is to investigate a Web‐based engineering approach to enable engineers to use, share, and simulate effectively and efficiently design and manufacturing data through the World Wide Web. The enabling techniques to implement such an approach are critically discussed with an example based on a tolerancing application and two Java‐based machining simulators for e‐manufacturing purposes, as well as an example of real‐time 3D implementation. The outcome of this research is for helping designers and manufacturing engineers to be able accurately to make the right decisions for their respective purposes.

Although data rich building information models have been widely adopted in the Architecture Engineering and Construction (AEC) industry in the United Kingdom (UK), use of 2D drawings on site for construction is still the norm. The ability of 2-dimensional (2D) drawings to convey complex 3-dimensional information is limited and requires interpretation from operatives, and 2D drawings can be quickly superseded by model updates. Although constructing directly from a model has been adopted in the aerospace and automotive industries, its use in construction is in its infancy. This research therefore aims to investigate the potential for, and barriers to, model-based construction in the UK.

This research uses a qualitative approach, thematically analysing 13 semi-structured interviews with UK-based construction professionals who have experience of paperless or model-based construction.

Although model -based construction has been implemented to a limited extent on some civil engineering projects; research and investment in software, network capacity, legal and contractual issues, and cultural and human factors will need to be considered before model-based construction can be implemented more widely.

The research contributes to an understudied, emergent area of construction practice and outlines hurdles that need to be understood and overcome before more widespread adoption of model-based construction can take place.

Preparing digital mock-ups (DMUs) for finite element analyses (FEAs) is currently a long and tedious task requiring many interactive CAD model transformations. Functional information about components appears to be very useful to speed this preparation process. The purpose of this paper is to shows how DMU components can be automatically enriched with some functional information.

DMUs are widespread and stand as reference model for product description. However, DMUs produced by industrial CAD systems essentially contain geometric models, which lead to tedious preparation of finite element Models (FEMs). Analysis and reasoning approaches are developed to automatically enrich DMUs with functional and kinematic properties. Indeed, geometric interfaces between components form a key starting point to analyze their behaviors under reference states. This is a first stage in a reasoning process to progressively identify mechanical, kinematic as well as functional properties of components.

Inferred semantics adds up to the pure geometric representation provided by a DMU and produce also geometrically structured components. Functional information connected to a structured geometric model of a component significantly improves FEM preparation and increases its robustness because idealizations can take place using components’ functions and components’ structure helps defining sub-domains of FEMs.

Future research will carry on improving algorithms for geometric interfaces identification, processing a wider range of component functions, which will contribute to a formalization of the concept of functional consistency of a DMU.

Simulation engineers benefit from this automated enrichment of DMUs with functional information to speed up the preparation of FEAs of large assemblies.