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Survivability strengthening/vulnerability reduction designs have become one of the most important design disciplines of military aircraft now. Due to progressiveness and complexity of modern combat aircraft, the existing vulnerability modeling and computation methods cannot meet the current engineering application requirements. Therefore, a vulnerability modeling and computation method based on product structure and CATIA is proposed in sufficient consideration of the design characteristics of modern combat aircraft. This method directly constructs the aircraft vulnerability model by CATIA or the digital model database, and manages all the product components of the vulnerability model via aircraft product structure. Using CAA second development, the detailed operations and computation methods of vulnerability analysis are integrated into CATIA software environment. Comprehensive assessment data and visual kill probability Iso-contours can also be presented, which meet the vulnerability analysis requirements of modern combat aircraft effectively. The intact vulnerability model of one hypothetical aircraft is constructed, and the effects of redundant technology to the aircraft vulnerability are assessed, which validate the engineering practicality of the method.

Developing high quality products with lower costs and in significantly less time is the key point for competitive strategies of companies. For complex and large variety of products this mission can be accomplished by the help of Concurrent Engineering techniques which require a collaborative way of working of relevant departments in a factory.In this paper, the way of constructing the digital environment in order to supply concurrent management of Product Data and management of product structure for different configurations and their engineering changes via workflows in the Product Life Cycle Management, PLM is described. Digital Mock Up, DMU the main element in simulating, testing and demonstrating the virtual product is another concern that is considered.

Planning rational product structure of coal preparation is the key to attain the maximization of economic benefit in coal preparation enterprise and to save energy resources. There are many factors effect the preparation product structure, such as raw coal quality, separating methods, coal price, processing cost, product quality demands and equipment performance, etc. The research focuses on the optimization of product structure under the Multi-factor influences. In order to maximizing the economic benefit, the algorithm model of product structure is established, and the multiple influence factors are transformed as model parameters and constraint conditions. Then the particle swarm optimization (PSO) algorithm is used to search the optimal scheme of product structure. According to the actual requirement, the model was divided into several child models during the calculation. A set of practical software has been developed based on the research. The result shows that using PSO algorithm can get better convergence effect and avoid the local optimization for the Multi-factor model and that the optimal scheme of product structure from the model accord with the practical situation.

Product structures represent the data backbone for through-life management of complex systems. Product Lifecycle Management (PLM) Systems are used to maintain product structures and track product changes. However, in maintenance, repair and overhaul (MRO) product composition often is unknown when MRO service providers are not the original manufacturers. Thus, MRO processes start with an exhaustive product diagnosis to identify elements to be maintained or replaced. Existing 3D scanning and data post processing methods have to be improved to acquire structured product data. This paper presents a method for automated derivation of product structures from 3D assembly models.

Planning multi-variant products in the early stage of the design process is still a challenge. In the present paper, a specification technique is introduced in order to define multi-variant products using degrees of freedom of shape attributes (in the following shape-DoFs) within the product structure. Our goal is to plan variety actively at the beginning of product development and not to describe variety by change of parameter values of the product's components as introduced in variant trees. Shape-DoFs are classified in the fields of shape attributes (dimension, position, shape as well as their combinations) on the one hand and mandatory or optional components on the other hand. Set up on this taxonomy graphical symbols are introduced to be used in product modeling. As application example, a welded pipe rack based upon the assembly structure modeling the product structure in this way is visualized in the first step. The second step is to translate the shape-DoFs into design parameters and identify relationships between them. The result is a parameter plan, as well as a configuration concept. Both can be seen as basis for CAD-modeling the product as design template which is the third step. In case of our example, Autodesk Inventor (without the ETO-Environment) is used to create the CAD-data. Discussing the effects of the proposed method, it will be shown that different shape-DoFs may cause various impacts in the whole product development process. Regarding these effects, scenarios can be performed in order to identify the cost and resource optimal variation possibilities of the product. In addition, it will be shown that different kinds of modularity according to PINE (e.g. cut-to-fit-modularity) can be predefined in the product model by using shape-DoFs

Our multidisciplinary team has virtually reconstructed the greatest church of the Romanesque period in Europe. The third church of the Abbey of Cluny (12th c.) has been destroyed after the French Revolution, leaving only 8% of the building standing. Many documents have been studied, to include the latest archaeological knowledge in the virtual model. Most remains have been scanned for CAD restitution. The mock-up of the church needed 1600 different numerical files, including the scanned pieces and the anastylosis of a Romanesque portal, a Gothic façade and a mosaic pavement. We faced various difficulties to assemble the different elements of the huge building, and to include the digitized parts. Our workflow consisted in generating geometrical shapes of the church, enriched with metadata such as texture, material... The whole mock up was finally exported to dedicated software to run the rendering step. Our work consisted in creating a whole database of 3D models as well as 2D sources (plans, engravings, pictures...) accessible by the scientific community. The scientific perspectives focus on a representation in virtual immersion of the grand church at scale 1 and an access to the digital mock-up through Augmented Reality.; International audience; Our multidisciplinary team has virtually reconstructed the greatest church of the Romanesque period in Europe. The third church of the Abbey of Cluny (12th c.) has been destroyed after the French Revolution, leaving only 8% of the building standing. Many documents have been studied, to include the latest archaeological knowledge in the virtual model. Most remains have been scanned for CAD restitution. The mock-up of the church needed 1600 different numerical files, including the scanned pieces and the anastylosis of a Romanesque portal, a Gothic façade and a mosaic pavement. We faced various difficulties to assemble the different elements of the huge building, and to include the digitized parts. Our workflow consisted in generating geometrical shapes of the church, enriched with metadata such as texture, material... The whole mock up was finally exported to dedicated software to run the rendering step. Our work consisted in creating a whole database of 3D models as well as 2D sources (plans, engravings, pictures...) accessible by the scientific community. The scientific perspectives focus on a representation in virtual immersion of the grand church at scale 1 and an access to the digital mock-up through Augmented Reality.

The paper deals with the use of a UML approach for the specifications of a PDM system (product data management) implementation. A PDM system enables the management of the whole product data and related information about its entire lifecycle. The main goal of this paper is to highlight the added value of using an object-oriented approach for modelling, specifying and implementing a PDM system on a business case study. The chosen object-oriented approach and the used UML diagrams for the modelling and integration of product, process, and resource data is detailed for a turboprop aircraft project.

In recent years, many process industries have been forced to drastically increase their product variety and adopt mass customization production strategies. Many of them have found that traditional bill of material (BOM) processing systems do not sufficiently support the maintenance of the very large amounts of data (concerned with product structure) demanded by these new production policies. Due to the use of BOM technology within the framework of integrated information systems, there is a demand for both (i) a new representation of BOMs, able to deal efficiently with product variants and to handle decomposition-based production strategies, and (ii) its corresponding BOM information processing system. This paper describes a conceptual representation that integrates elements of semantic relationships with object-oriented concepts to develop a data model for a hybrid bill of materials. The proposed semantic relationships include composed-of, decomposed-into, variant-of, restriction-of, and their corresponding reverse relationships. The conceptual model has been implemented using object-oriented data-based management system (OODBMS) technology that allows creation of persistent Java objects. Preliminary tests show a remarkable reduction in the number of relationships when compared with former approaches.

This work closes a knowledge gap, which hindered the exploration of the relationships between complexity and quality in full. Recent decades are characterized by rapid technological progress, which has been followed by elevated product complexity. Many repercussions of this growing complexity have already been considered, but the work has not yet been completed and this study adds a significant contribution. While not the sole, the most straight-forward expression of product's complexity level is the number of components, which are assembled to make this product – the more components, the higher the complexity. In serial manufacturing processes, each item moves individually, but items are joined together, serially or in parallel, in assemblies. There, mutual effects exist – a single defective component suffices to disqualify a whole assembled unit! Surprisingly, few studies have considered the effects of defective items on the production process. Particularly, there appears to be no study that quantifies these mutual effects among components which arrive from different sources with different defect rates. Thus, this study appears to be a first attempt to analyze and quantify these effects. Evidently, the mutual effects among their components amplify assemblies’ defect rates dramatically, to the extent that defects due to common or random causes become significant. This hypothesis is supported by both the result of this study and field data from the industry. This is a price of advanced products – increased complexity which sets hurdles on the preservation of quality; a price that should be considered in the course of product design. However, the present analysis reveals that setting quality assurance activities just prior to assembly operations reduces the mutual effects among components. Consequently, process design can be used to overcome undesirable repercussions of increased product complexity, thereby increase the yield of the production process.