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1 – 10 of over 3000Ming-min Liu, L.Z. Li and Jun Zhang
The purpose of this paper is to discuss a data interpolation method of curved surfaces from the point of dimension reduction and manifold learning.
Abstract
Purpose
The purpose of this paper is to discuss a data interpolation method of curved surfaces from the point of dimension reduction and manifold learning.
Design/methodology/approach
Instead of transmitting data of curved surfaces in 3D space directly, the method transmits data by unfolding 3D curved surfaces into 2D planes by manifold learning algorithms. The similarity between surface unfolding and manifold learning is discussed. Projection ability of several manifold learning algorithms is investigated to unfold curved surface. The algorithms’ efficiency and their influences on the accuracy of data transmission are investigated by three examples.
Findings
It is found that the data interpolations using manifold learning algorithms LLE, HLLE and LTSA are efficient and accurate.
Originality/value
The method can improve the accuracies of coupling data interpolation and fluid-structure interaction simulation involving curved surfaces.
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Presents a method for unfolding the cerebral cortex and other folded surfaces. Discusses the problem of unfolding such surfaces and gives examples of its complexity. Proposes an…
Abstract
Presents a method for unfolding the cerebral cortex and other folded surfaces. Discusses the problem of unfolding such surfaces and gives examples of its complexity. Proposes an algorithm and suggests software implementation. Considers the presumed functions on cortical surface and discusses clinical applications.
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Abstract
Nowadays, simplified inverse or one step approaches for the sheet forming modeling are increasingly used in the automobile industry, since they allow to quickly realize the preliminary design and especially to optimize the process parameters. These methods often based on implicit static algorithms cause sometimes convergence problems because of strong non‐linearities. This paper deals with several initial guess methods to speed up the convergence of the implicit static solver used in the inverse approach for stamping modeling. The blank's mesh as initial solution is obtained by geometrical considerations based on the known shape of the final 3D workpiece. Three algorithms for the estimation of the blank's mesh have been developed and compared. The application to several industrial problems shows their efficiency and performance.
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Wolfgang Fischer, Gilles Caprari, Roland Siegwart, Igor Thommen, Wolfgang Zesch and Roland Moser
The purpose of this paper is to describe the design and prototype implementation of a miniature climbing robot with magnetic adhesion, developed for the inspection of gas turbines…
Abstract
Purpose
The purpose of this paper is to describe the design and prototype implementation of a miniature climbing robot with magnetic adhesion, developed for the inspection of gas turbines and other environments that require vertical mobility along curved steel surfaces, but only offer very narrow access holes – in the case of turbines only Ø15 mm.
Design/methodology/approach
After a detailed description and analysis of the industrial environment where the robot is supposed to be used (inspection of gas turbines, housing not opened), the paper describes the basic mechanical concept which is based on two traction units on magnetic wheels and a folding mechanism which allows the robot for changing between two configurations – one for passing through the narrow access holes and one for climbing with 2D mobility on curved surfaces. A special focus is put on how the most difficult design challenges were solved – torque transmission at this very small size and the design of the folding mechanism.
Findings
The feasibility of the concept is proven with a prototype implementation and successful test results.
Research limitations/implications
Discussions with field service engineers at ALSTOM showed that gas turbines are relatively easy to open thus do not require access through the narrow bore‐scope‐holes.
Practical implications
However, in the field of boiler drum inspection, there is a need for such robots. The final industrial version of this robot, which is currently under development at ALSTOM Inspection Robotics, is optimized for this type of environments (more space but higher requirements regarding the robustness against shocks).
Originality/value
The robot concept presented here allows for accessing environments with very narrow access holes and afterwards climb with 2D mobility – an ability which opens several new applications for compact mobile climbing robots, especially in the field of power plant inspection.
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A method has been developed for computing aerodynamic loads on slender missiles with complicated cross‐sections. This method has been applied to the prediction of loads for…
Abstract
A method has been developed for computing aerodynamic loads on slender missiles with complicated cross‐sections. This method has been applied to the prediction of loads for missiles with folding wings. Comparison of theoretical calculations with supersonic wind‐tunnel measurements indicates that the method should provide satisfactory first estimates of the aerodynamic properties of missiles with folding wings. A series of design charts is presented to allow rapid estimation of lift, folding moment and span loading for a wide variety of folding‐wing configurations.
Chen Bao, Yongwei Miao, Bingfei Gu, Kaixuan Liu and Zhen Liu
The purpose of this paper is to propose an interactive 2D–3D garment parametric pattern-making and linkage editing scheme that integrates clothing design, simulation and…
Abstract
Purpose
The purpose of this paper is to propose an interactive 2D–3D garment parametric pattern-making and linkage editing scheme that integrates clothing design, simulation and interaction to design 3D garments and 2D patterns. The proposed scheme has the potential to satisfy the individual needs of fashion industry, such as precise fit evaluation of the garment, interactive style editing with ease allowance and constrained contour lines in fashion design.
Design/methodology/approach
The authors first construct a parametric pattern-making model for flat pattern design corresponding to the body dimensions. Then, the designing 2D patterns are stitched on a virtual 3D mannequin by performing a virtual try-on. If the customer is unsatisfied after the virtual try-on, the adjustable parameters (appearance parameters and fit parameters) can be adjusted using the 2D–3D linkage editing with hierarchical constrained contour lines, and the fit evaluation tool interactively provides the feedback.
Findings
The authors observed that the usability and efficiency of the existing garment pattern-making method simplifies the garment pattern-making process. The authors utilize an interactive garment parametric flat pattern-making model to generate an individualized garment flat pattern that effectively adjust and realize the local editing of the garment pattern-making. The 2D–3D linkage editing is then employed, which alters the size and shape of garment pattern for a precise human model fit of the 3D garment using hierarchical constrained contour lines. Various instances have validated the effectiveness of the proposed scheme, which can increase the reusability of the existing garment styles and improve the efficiency of fashion design.
Research limitations/implications
First, the authors do not consider the garment pattern-making design of sophisticated styles. Second, the authors do not directly consider complex garment shapes such as wrinkles, folds, multi-layer models and fabric physical properties.
Originality/value
The authors propose a pattern adjustment scheme that uses the 3D virtual try-on technology to avoid repetitions of reality-based fit tests and garment sample making in the designing process of clothing products. The proposed scheme provides interactive selections of garment patterns and sizes and renders modification tools for 3D garment designing and 2D garment pattern-making. The authors present the 2D–3D interactive linkage editing scheme for a custom-fit garment pattern based on the hierarchical constraint contour lines. The spatial relationship among the human body, pattern pieces and 3D garment model is adequately expressed, and the final design result of the garment pattern is obtained by constraint solving. Meanwhile, the tightness tension of different parts of the 3D garment is analyzed, and the fit and comfort of the garment are quantitatively evaluated.
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A surface view of monotheistic or “Western” religions might lead some to infer a singularity to truth that is inconsistent with paradoxical thinking. The author explores a key…
Abstract
A surface view of monotheistic or “Western” religions might lead some to infer a singularity to truth that is inconsistent with paradoxical thinking. The author explores a key Biblical narrative common to both Judaism and Christianity – the story of origins that unfolds in the Garden of Eden. The author posits that the foundations of those belief systems, and particularly those of Christian theology, are paradoxical as evidenced in their historic texts (i.e., the Old and New Testaments of the Bible). A foundational paradox of an “ought versus is” (ideal vs. actual) tension that underlies or intertwines in knot-like fashion with other paradoxes is identified in ways that account for a current world view marked by temporality (in tension with eternality) and becoming (in tension with being). These tensions are made salient as humans continually work toward ideals that seem always just out of reach. Paradox conceptualization is also expanded to propose the notion of mutual embeddedness rather than mutual exclusivity of opposites. Implications for organizational paradoxes are explicated, along with directions for future research based on novel insights provided by the juxtaposition of religion and paradox.
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Yijie Zhang, Ling Ma, Ziyi Guo, Tao Li and Fengyuan Zou
Considering only two-dimensional (2D) ease allowance cannot fully reflect the three-dimensional (3D) relationship between the position of clothing and the human body. The purpose…
Abstract
Purpose
Considering only two-dimensional (2D) ease allowance cannot fully reflect the three-dimensional (3D) relationship between the position of clothing and the human body. The purpose of this paper is to propose a method with a 3D space vector and corresponding distance ease to characterize fitting garments and then used to construct personalized clothing for similar shape body.
Design/methodology/approach
Firstly, a 3D scanner was used to obtain mannequin and fitted garment data, and 17 layers of cross-sections of the upper body were extracted. Then, 37 space vectors and corresponding space angles on each cross-section were obtained with the original point. Secondly, the detailed distance ease between the mannequin and garment was constructed due to the difference between garment vectors and body vectors. Thirdly, the distance ease mathematical models were achieved and used to calculate distance ease on a similar shape body. Additionally, the fit garment is constructed, and the garment pattern is altered by the geometric pattern alteration method.
Findings
The results show that 3D space vectors can explain the relationship between body skin and garment surface of the upper body properly. The distance ease is modeled by mathematic expressions and successfully used to make a new garment to fit a similar shape body.
Originality/value
The proposed method of constructing garments based on distance ease and 3D space vectors can create a fitted garment for a similar shape body effectively and accurately. It is useful for the personalized garment design and suitable for the manufacturing process.
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Wei Xia, Sheng‐Rui Yu and Xiao‐Ping Liao
The purpose of this paper is to establish a paint deposition pattern model applied to robotic air spray painting in order to achieve the accuracy and uniformity of paint film…
Abstract
Purpose
The purpose of this paper is to establish a paint deposition pattern model applied to robotic air spray painting in order to achieve the accuracy and uniformity of paint film thickness on free‐form surface.
Design/methodology/approach
The paper opts for an exploratory study using the curvature circle method for air spray painting on free‐form surface to construct a spray gun model. First, a paint deposition pattern model of ellipse dual‐β distribution is fitted on the basic of experimental data from robotic air spray painting. Second, a spray gun model is proposed using the curvature circle method for air spray painting on free‐form surface. The theoretical result is coincident with the film thickness in verification experiment spraying a cylinder surface. The biggest error of the sample points between the theoretical and experimental results is less than 4 μm, thereby the correctness and effectiveness of the proposed model is validated.
Findings
The paper provides a specific theoretical and methodological support for the realization of process planning and simulation system in surface spray manufacturing. It will make the future developed system meet the actual processing requirement. At the same time, it is more representative.
Originality/value
The paper finds an approach to solve paint deposition pattern model suitable to free‐form surface. The present method can be applied to the complex reality of topological relation for actual workpiece surface to be painted.
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Jian Ping Wang and Wei Yuan Zhang
The aim of this paper is to explore a method of predicting the amount of personalized bra cup dart in the 3D virtual environment for supporting the made‐to‐measure research of the…
Abstract
Purpose
The aim of this paper is to explore a method of predicting the amount of personalized bra cup dart in the 3D virtual environment for supporting the made‐to‐measure research of the optimum fitted brassiere pattern design.
Design/methodology/approach
Very useful enhanced FFD (free‐form‐deformation) techniques used in both computer animation and geometric modeling were skillfully transplanted to the female breast model deformation. Meanwhile, on the basis of 3D scan and surface modeling technologies, the realization approach of the abstract female breast model library focusing on the individual variations of shapes and sizes was presented. Then according to the principle of isometric area and flabellate segments, the personalized bra cup dart quantity and its distributive information were provided by 3D‐2D transformation.
Findings
The paper finds that personalized female breast shapes and various aesthetic breast forms sculpted by different bras could be interactively simulated. Accordingly, the amount of corresponding individual bra cup dart and its distributive information were provided. The cup darts were mainly distributed below the bust line. Moreover, dart shapes were curvy.
Research limitations/implications
The principles of virtual breast library construction and 3D‐2D transformation are also suitable for other parts of the human body such as buttocks, abdomen and, etc. for intimate apparel research.
Originality/value
The method of predicting the personalized bra cup dart quantity based on the 3D virtual breast model library was delivered for the first time. The novel findings provided an important guideline for designers to improve the well‐fitted bra pattern design technique. Furthermore, it would reduce the manufacturing cost without keeping physical dummies.
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