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The purpose of this paper is to present a skin-based approach able to generate the variability model for a component in composite material due to its manufacturing process. It generates a skin-based model of the manufactured part. The skin model discretizes the part surfaces by points to take into account the geometric deviations, those points are the nodes of finite element analysis used for tolerance analysis of compliant assemblies.

The paper presents a general and systematic simulation model for generating a variability meta-model for a component in composite material due to its manufacturing process. The model is constituted by three steps: definition and pre-processing of the nominal model, generation of the manufacturing process model and evaluation of the part variability.

The advantage of this approach is related to the fact that it is designed as a part of a digital process that establishes a continuous and unambiguous flow of variation information from the part design to manufacturing and assembly and that takes into account the manufacturing signature. This is its uniqueness compared to other simulation approaches focused only on manufacturing.

Considering the variability around the nominal value of all the process parameters and parts with more complex geometries are not taken into account now, which will be modelled in practical applications.

To properly manage uncertainty since conceptual design of complex product, next generation geometry assurance requires simulation models to realistically consider process signatures due to the manufacturing process. This work focusses on this next generation tool for geometry assurance.

The literature is focused on metal sheets joined by welding or riveting. There are other materials widely used and typically compliant: the composite materials that typically used mechanical fixing elements (bolting, riveting) and structural adhesives to joint parts. No software tools exist in the literature to deal with uncertainty from manufacturing to assembly processes in products made by composite. This is the reason of the present work.

The purpose of this work is to present a variational model able to deal with form tolerances and assembly conditions. The variational model is one of the methods proposed in literature for tolerance analysis, but it cannot deal with form tolerances and assembly conditions that may influence the functional requirements of mechanical assemblies.

This work shows how to manage the actual surfaces generated by the manufacturing process and the operating conditions inside the variational model that has been modified to integrate the manufacturing signature left on the surfaces of the parts and the operating conditions that arise during an actual assembly, such as gravity and friction. Moreover, a geometrical model was developed to numerically simulate what happens in a real assembly process and to give a reference value.

The new variational model was applied to a three-dimensional case study. The obtained results were compared to those of the geometrical model and to those of the variational model to validate the new model and to show the improvements.

The proposed approach may be extended to other models of literature. However, its limitation is that it is able to deal with a sphere–plane contact.

Tolerance analysis is a valid tool to foresee geometric interferences among the components of an assembly before getting the physical assembly. It involves a decrease in the manufacturing costs.

The main contributions of the study are the insertion of a systematic pattern characterizing the features manufactured by a process, assembly operating conditions and development of a geometrical model to reproduce what happens in a real assembly process.

Developing countries engaged in apparel value chain are going global, seeking opportunities to upgrade the industry through providing higher value-added products and services. The purpose of this paper is to investigate how Sri Lankan apparel industry designers interact with the western fashion world in the apparel value chain process, and how they acquire, adapt and apply the knowledge needed to develop high-value fashion products in their fashion design practice.

The study adopts a qualitative approach through semi-structured interviews conducted with fashion design and product development professionals in the Sri Lankan apparel industry. An inductive thematic analysis is used in identifying participants’ experience of the western fashion world within their fashion design practice.

The study proposes a “fashion knowledge bridge” illustrating the ways in which Sri Lankan designers acquire and merge high-value fashion consumer culture and lifestyle knowledge with the manufacturing industry, through multisensory and virtual experience, termed “exposure”, in their interactions with the western fashion world as well as the manufacturing culture of the Sri Lankan apparel industry. Designers’ exposure improves the feasibility and reliability of their apparel products, aligning to the end-consumer needs. The study also proposes a “designers’ exposure framework” that illustrates gains made by the Sri Lankan apparel industry resulting from knowledge enhancement through the designers’ exposure.

The study is based on a qualitative methodology that has potential subjective biases on the part of the researchers; in this case only the Sri Lankan designers’ perspectives were used in synthesising the findings.

The findings propose frameworks with theoretical and managerial implications for developing designers’ capabilities in apparel manufacturing countries that seek industrial upgrading through value-added fashion design practice.

The purpose of this paper is to explore how Australian fashion designers perceive the impact and opportunities offered by the Chinese textile and clothing industry.

A qualitative research design used personally administered, semi‐structured interviews. A purposeful sample used interviewees drawn from proactive fashion business owners. The sample covered four clothing categories. Thematic data analysis was used, and data integrity was assured, using well‐recognised techniques including triangulation and constant comparison.

The Queensland fashion designers are experiencing significant impacts from the current economic and manufacturing situations and the challenges presented by developments in China. They respond to their operational concerns, but do not deal strategically with contemporary challenges. They are unaware of opportunities that the Chinese textile and clothing industry offers, struggling with a global perspective. Although they are aware of issues with intellectual property, they have little experience in protecting their intangible assets.

Future research could link the proposed scenario building with interviews, to develop an even more robust research design. Extensions to other Asia Pacific countries could reveal common issues and any unique perspectives.

Application of the proposed model and the pursuit of the scenarios for future development could assist fashion designers in the formation of a sense of community. A return to craftsmanship could nurture the local fashion design community, and create offshore links and relationships, facilitated by technology.

The empirical study proposes a new model, suggesting approaches and solutions, not previously considered in the context of fashion designers and their opportunities in doing business with China.

The purpose of this paper is to model how geometric errors of a machined surface (or manufacturing errors) are related to locators’ error, workpiece form error and machine tool volumetric error. A kinematic model is presented that puts into relationship the locator error, the workpiece form deviations and the machine tool volumetric error.

The paper presents a general and systematic approach for geometric error modelling in drilling because of the geometric errors of locators positioning, of workpiece datum surface and of machine tool. The model can be implemented in four steps: (1) calculation of the deviation in the workpiece reference frame because of deviations of locator positions; (2) evaluation of the deviation in the workpiece reference frame owing to form deviations in the datum surfaces of the workpiece; (3) formulation of the volumetric error of the machine tool; and (4) combination of those three models.

The advantage of this approach lies in that it enables the source errors affecting the drilling accuracy to be explicitly separated, thereby providing designers and/or field engineers with an informative guideline for accuracy improvement through suitable measures, i.e. component tolerancing in design, machining and so on. Two typical drilling operations are taken as examples to illustrate the generality and effectiveness of this approach.

Some source errors, such as the dynamic behaviour of the machine tool, are not taken into consideration, which will be modelled in practical applications.

The proposed kinematic model may be set by means of experimental tests, concerning the industrial specific application, to identify the values of the model parameters, such as standard deviation of the machine tool axes positioning and rotational errors. Then, it may be easily used to foresee the location deviation of a single or a pattern of holes.

The approaches present in the literature aim to model only one or at most two sources of machining error, such as fixturing, machine tool or workpiece datum. This paper goes beyond the state of the art because it considers the locator errors together with the form deviation on the datum surface into contact with the locators and, then, the volumetric error of the machine tool.

With an annual cost of gold exceeding 10 million dollars for its captive circuit board shop, Tektronix, Inc., established a task force to implement conservation. Elements included Purchasing, Material Control, Quality Assurance, Manufacturing and Engineering. Salient programme items were inventory reduction, material accountability, modification of processes, procedures, and equipment to improve uniformity of thickness, and elimination of non‐essential gold use. In addition, scrap‐handling procedures were modified to improve accountability and reclaim returns.

The purpose of this paper is to carry out an assembly tolerance analysis by means of a combined Jacobian model and skin model shape. The former is based on small displacements modeling of points using 6 × 6 transformation matrices of open kinematic chains in robotics. The latter easily models toleranced features with all kinds of geometric deviations.

This paper presents the procedure of performing tolerance analysis by means of the Jacobian model and skin model shape for assemblies. The point cloud-based discrete representative is able to model the actual toleranced surfaces instead of the ideal or associated ones in an assembly, which brings the simulation tools closer to reality.

The proposed method has the advantage of skin model shape which is suitable for geometric tolerances management along the product life cycle and contact analysis of kinematic small variations, as well as, with the Jacobian, enabling transformation of locally expressed parts deviations to globally expressed functional requirements. The result of the case study shows the accuracy of the method.

The proposed approach has not been developed fully; other functional features such as the pyramid are still ongoing challenges.

It is an effective method for supporting design, manufacturing and inspection by providing a quantitative analysis of the effects of multi-tolerances on the final functional key characteristics and for predicting the quality level.

The paper is original in taking advantages of both Jacobian model and skin model shape to consider all geometric tolerances in assembly.

The purpose of this paper is to review the 2007 ATExpo Show and related Electronics Assembly Show, Quality, PlasTec and National Manufacturing Week Shows held jointly in Chicago.

In‐depth interviews were conducted with exhibitors who provide assembly systems, controls, grippers and other assembly systems components.

Though automated assembly has been around many decades, suppliers have continued to innovate new technologies, controllers and software that enhance the automated assembly process.

The paper is of value in confirming that suppliers are continuing to develop assembly cells, modular elements, software and other related components that help make the design and commissioning of systems faster and cheaper. Automated assembly is a truly competitive approach to reducing cost of assembly, quality of products produced and efficiently managing resources.

This paper aims to develop a mathematical method to analyze the assembly variation of the non-rigid assembly, considering the manufacturing variations and the deformation variations of the non-rigid parts during the assembly process.

First, this paper proposes a deformation gradient model, which represents the deformation variations during the assembly process by considering the forces and the self-weight of the non-rigid parts. Second, the developed deformation gradient models from the assembly process are integrated into the homogenous transformation matrix to model the deformation variations and manufacturing variations of the deformed non-rigid part. Finally, a mathematical model to analyze the assembly variation propagation is developed to predict the dimensional and geometrical variations due to the manufacturing variations and the deformation variations during the assembly process.

Through the case study with a crosshead non-rigid assembly, the results indicate that during the assembly process, the individual deformation values of the non-rigid parts are small. However, the cumulative deformation variations of all the non-rigid parts and the manufacturing variations present a target value (w) of −0.2837 mm as compared to a target value of −0.3995 mm when the assembly is assumed to be rigid. The difference in the target values indicates that the influence of the non-rigid part deformation variations during the assembly process on the mechanical assembly accuracy cannot be ignored.

In this paper, a deformation gradient model is proposed to obtain the deformation variations of non-rigid parts during the assembly process. The small deformation variation, which is often modeled using a finite-element method in the existing works, is modeled using the proposed deformation gradient model and integrated into the nominal dimensions. Using the deformation gradient models, the non-rigid part deformation variations can be computed and the accumulated deformation variation can be easily obtained. The assembly variation propagation model is developed to predict the accuracy of the non-rigid assembly by integrating the deformation gradient models into the homogeneous transformation matrix.