Shape Creation Research Articles

디지털디자인도구의 Geometry 변형을 통한 비정형 디자인 형태 생성 방법에 관한 연구

디지털디자인도구의 Geometry 변형을 통한 비정형 디자인 형태 생성 방법에 관한 연구

Sub-micron fracture mechanism in silica-based glasses activated by permanent densification from high-strain loading

Several silica-based glasses were fractured at high strain energy via drop-weight testing on small specimens. A cylindrical specimen geometry was chosen to promote initially simple, axisymmetric, and uniform compressive loading. The imposed uniaxial compressive strain at impact was sufficiently high to qualitatively cause permanent densification. Produced fragments were collected for postmortem and a fraction of them, for all the silica-based glasses, consistently had distinct sub-micron-sized fractures (~300–1000nm), designated here as “microkernels”, on their surfaces. They would most often appear as a sub-micron pore on the fragment - apparently if the microkernel had popped out as a consequence of the local crack plane running through it, tensile-strain release, and the associated formation of the fragment it was on. No fractographic evidence was found to show the microkernels were associated with local failure initiation. However, their positioning and habit sometimes suggested they were associated with localized crack branching and that they could have influenced secondary fracturing that occurred during overall crushing and comminution and associated fragment size and shape creation. The size range of these microkernels is much too small to affect structural flexure strength of these glasses for most applications but are of a size and concentration that may affect their ballistic, shock, crush, and comminution responses when permanent densification is concomitantly occurring.

Constitutive modeling of the mechanics associated with triple shape memory polymers

Shape memory polymers (SMPs) are smart materials that alter their shape in response to external stimuli. Dual-shape SMPs are widely recognized and are characterized by two shapes involved in a typical shape memory cycle. Recently, triple-shape memory polymers (TSMPs) have been introduced that have the ability to remember three shapes. Thermo-sensitive TSMPs can perform two sequential shape changes in response to heat, which were programed previously in a triple-shape creation process (TSCP). TSMPs are technologically significant as their development of has led to emergence of many complex potential applications that cannot be achieved by dual-shape polymers (Zhao et al., 2013). Crystallizable TSMPs are a class of thermo-sensitive TSMPs, where the shape creation is due to formation of crystalline phases. Different TSCPs have been reported which enable to control the triple shape capability of these materials. In this work the mechanical behavior of TSMPs has been modeled using a framework that has been developed recently for studying crystallization in polymers (Rao, 2003; Rao and Rajagopal, 2001, 2002, 2004). The framework has been used successfully to model SMPs (Barot and Rao, 2006; Barot et al., 2008), light activated SMPs (Sodhi and Rao, 2010) and is based upon the theory of multiple natural configurations. The model has been used to simulate a uni-axial deformation cycle for different types of TSCPs and the results have been compared with experimental data.

Current State of the Art of Multi-Axis Control Machine Tools and CAM System

<div class=""abs_img""><img src=""[disp_template_path]/JRM/abst-image/00260005/01.jpg"" width=""300"" />Asymmetric curved grooving</div> Multi-axis numerical control (NC) machine tools such as 5-axis control machining centers and 5-axis control multi-tasking machines are widely used in machine shops. NC data, which are prepared using computeraided manufacturing (CAM) systems, are used with multi-axis control NC machine tools that have a variety of advantages. This article describes the advantages ofmulti-axis control machining. The structure of CAM systems used for multi-axis control machining and the important role of collision avoidance in generating cutter location (CL) data are then explained. The transformation of CL data to NC data for use in machining, which is performed by a post-processor, is presented. Finally, an efficient machining method and unique shape creation via 6-axis control machining are explained. </span>

Reprogramming the hand: Bridging the craft skills gap in 3D/digital fashion knitwear design

Abstract Designer-makers have integrated a wide range of digital media and tools into their practices, many taking ownership of a specific technology or application and learning how to use it for themselves, often drawing on their experiential knowledge of established practices to do so. To date, there has been little discussion on how digital knitting practice has evolved within this context, possibly due to the complexity of the software, limited access to industrial machinery and the fact that it seems divorced from the idea of ‘craft’. Despite the machine manufacturers’ efforts to make knitting technology and software more user-friendly, the digital interface remains a significant barrier to knitwear designer-makers, generally only accessed via experienced technicians. This article focuses on how this issue is being explored through practice-led research being undertaken by Jane Taylor at Nottingham Trent University. The investigation is a response to a skills gap between knitwear designers and the latest flatbed knitting technology and is grounded within the researcher’s experience as both a knitwear designer and technologist. Through her practice, Taylor explores how the Shima Seiki SDS1 CAD system can be used as a design tool, in order to use the SWG (3D Knit) machines more creatively. Specialist training has built on the researcher’s tacit understanding of hand/machine knitting and pattern cutting, her established craft practice, where constant iterations can be made during the textile and shape creation stage. By reprogramming the hand, this research proposes a craft-based methodology that reverses the traditional relationship between making and technology, placing crafting at the centre of creative design practice where it can be applied to support and further the potential of advanced technology. This article is a revised version of a paper that was first presented by the authors at The First International Conference on Digital Fashion, at London College of Fashion in May 2013.

Topology-varying 3D shape creation via structural blending

We introduce an algorithm for generating novel 3D models via topology-varying shape blending. Given a source and a target shape, our method blends them topologically and geometrically, producing continuous series of in-betweens as new shape creations. The blending operations are defined on a spatio-structural graph composed of medial curves and sheets. Such a shape abstraction is structure-oriented, part-aware, and facilitates topology manipulations. Fundamental topological operations including split and merge are realized by allowing one-to-many correspondences between the source and the target. Multiple blending paths are sampled and presented in an interactive, exploratory tool for creative 3D modeling. We show a variety of topology-varying 3D shapes generated via continuous structural blending between man-made shapes exhibiting complex topological differences, in real time.

3D shape creation by style transfer

In this paper, we propose a new style transfer method for automatic 3D shape creation based on new concepts of style and content of 3D shapes. Our unsupervised style transfer method could plausibly create novel shapes not only by recombining existent styles and contents in a set but also by combining new-coming styles or contents with the existent ones conveniently. This feature provides a better way to increase the diversity of created shapes. The process of shape creation can be summarized as two stages. First, style and content separation is performed to analyzed shapes in a set. Second, novel shapes are created by style transfer. In our setting, contents are first separated via clustering shapes using a new defined global shape distance, and then, style parts are clustered into different style classes. Specifically, style parts are extracted from each pair of intra-content shapes through comparing their multi-scale corresponding patches instead of corresponding parts. This strategy makes the process of extracting style parts become insensitive to slight geometric changes. The multi-scale corresponding patches are obtained via partitioning the two shapes in a consistent way by the proposed correspondence transfer. Meanwhile, to quantify the comparison results for locating style parts, a novel local shape difference function (LSDF) is introduced. Based on LSDF, extracting a style part from each shape is formulated as an optimal LSDF threshold selection problem. In the experiments, we test our method in several sets of man-made 3D shapes and obtain plausible created shapes based on the reasonably separated styles and contents.

CAD client on smart device with drag-type buttons

Smart devices have been developed and widely used recently, so they have been applied in the industrial field. If mobile technology is applied to the CAD field, users will be able to obtain many advantages such as high mobility and ease of collaboration. To develop a feature-based CAD system that can be made available on smart devices, we suggested a system using multi-touch inputs in 2012; this was a stand-alone system available without a network. However, the system could not create complex shapes by itself because of the absence of a modeling kernel for the mobile platform and the low computing power of smart devices. To solve this problem of shape creation, this study proposes a client-server system for CAD systems on smart devices. When modeling commands are created from drag-type buttons, at each step, the analyzed modeling commands are sent to the server, the server creates the model and sends it to the smart device, and the smart device visualizes the modeling result. This system can make more complex models than those possible with the existing system. This study compares the developed system with the existing system in order to verify the usability of the new CAD system on smart devices; further, this study suggests how to extend this system to collaborative systems. This CAD system for smart devices can increase the mobility and cooperative nature of CAD systems.

Handy-Potter: Rapid Exploration of Rotationally Symmetric Shapes Through Natural Hand Motions

Abstract We present a paradigm for natural and exploratory shape modeling by introducing novel 3D interactions for creating, modifying, and manipulating 3D shapes using arms and hands. Though current design tools provide complex modeling functionalities, they remain nonintuitive for novice users. Significant training is required to use these tools since they segregate 3D shapes into hierarchical 2D inputs, binding the user to stringent procedural steps and making modifications cumbersome. On the other hand, the use of computer-aided design (CAD) systems is typically involved during the final phases of design. This leaves a void in the early design phase wherein the creative exploration is critical. We present a shape creation paradigm as an exploration of creative imagination and externalization of shapes, particularly in the early phases of design. We integrate the capability of humans to express 3D shapes via hand-arm motions with traditional sweep surface representation to demonstrate rapid exploration of a rich variety of 3D shapes. We track the skeleton of users using the depth data provided by low-cost depth sensing camera (Kinect). Our modeling tool is configurable to provide a variety of implicit constraints for shape symmetry and resolution based on the position, orientation, and speed of the arms. An intuitive strategy for shape modifications is also proposed. Our main goal is to help the user to communicate the design intent to the computer with minimal effort. To this end, we conclusively demonstrate the creation of a wide variety of product concepts and show an average modeling time of a only few seconds while retaining the intuitiveness of the design process.

From A Medial Surface To A Mesh

AbstractMedial surfaces are well‐known and interesting surface skeletons. As such, they can describe the topology and the geometry of a 3D closed object. The link between an object and its medial surface is also intuitively understood by people. We want to exploit such skeletons to use them in applications like shape creation and shape deformation. For this purpose, we need to define medial surfaces as Shape Representation Models (SRMs). One of the very first task of a SRM is to offer a visualization of the shape it describes. However, achieving this with a medial surface remains a challenging problem.In this paper, we propose a method to build a mesh that approximates an object only described by a medial surface. To do so, we use a volumetric approach based on the construction of an octree. Then, we mesh the boundary of that octree to get a coarse approximation of the object. Finally, we refine this mesh using an original migration algorithm. Quantitative and qualitative studies, on objects coming from digital modeling and laser scans, shows the efficiency of our method in providing high quality surfaces with a reasonable computational complexity.

Ordered Statistics Vertex Extraction and Tracing Algorithm (OSVETA)

We propose an algorithm for identifying vertices from three dimensional (3D) meshes that are most important for a geometric shape creation. Extracting such a set of vertices from a 3D mesh is important in applications such as digital watermarking, but also as a component of optimization and triangulation. In the first step, the Ordered Statistics Vertex Extraction and Tracing Algorithm (OSVETA) estimates precisely the local curvature, and most important topological features of mesh geometry. Using the vertex geometric importance ranking, the algorithm traces and extracts a vector of vertices, ordered by decreasing index of importance.

Exploiting Microphase‐Separated Morphologies of Side‐Chain Liquid Crystalline Polymer Networks for Triple Shape Memory Properties

AbstractWe report a new strategy to achieve triple shape memory properties by using side‐chain liquid crystalline (SCLC) type random terpolymer networks (XL‐ TP‐n), where n is the length of flexible methylene spacer (n = 5, 10, and 15) to link backbone and mesogen. A lower glass transition temperature (Tg = Tlow) and a higher liquid crystalline clearing temperature (Tcl = Thigh) of XL‐TP‐n serve as molecular switches to trigger a shape memory effect (SME). Two different triple shape creation procedures (TSCPs), thermomechanical treatments to obtain temporary shapes prior to the proceeding recovery step, are used to investigate the triple shape memory behavior of XL‐TP‐n. The discrete Tg and Tcl as well as unique microphase‐separated morphologies (backbone‐rich and mesogen‐rich domains) within smectic layers of XL‐TP‐n enables triple shape memory properties. Motional decoupling between backbone‐rich and mesogen‐rich domains is also critical to determine the resulting macroscopic shape memory properties. Our strategy for obtaining triple shape memory properties will pave the way for exploiting a broad range of SCLC polymers to develop a new class of actively moving polymers.

L-system 모델을 이용한 대공간 구조물의 형태생성 방안

This study presents the shape creation process using L-system model of morphogenesis technique. In general, L-system model has been applied to represent the visualization of biological plant. But, this study proposes the shape generation process of L-system model to apply the architectural field. The L-system model consists of two parts such as string generation step and string analysis step. The string generation step shows the process for a string rewriting. This step requires alphabet, axiom and rules to generate a string. Also, the string analysis step gives the meaning in string to generate various forms. Especially, through the various application examples, we can find out the shape creation models for the space structures.

Interactive visualisation of algebraic surfaces as a tool for shape creation

Mathematical models gain an increasing interest as a source of inspiration for applications in fine art, design and architecture. Here, we investigate implicitly defined algebraic surfaces to create interesting looking and often very beautiful objects. Interactive and real time visualisation can help to explore the full potential of such surfaces. For this purpose we provide our tool REALSURF, which uses modern graphics processor programming techniques to achieve real time visualisation performance. We give a brief introduction to the underlying algorithms and we will show several approaches, that aid the process of designing interesting algebraic surfaces.

The implementation of a sketch-based virtual product development

Within the product development process, working in virtual environments is generally applied. Thus, the digital product model in its different stages is an essential prerequisite for the virtual modeling and simulation of manufacturing processes. Product development starts with conceptual design including the concepts for shape and function. The conceptual designers work on fuzzy product data applied to perception modeling and shape creation. For some time now, there has been a strong demand to define creative human problem solving in conceptual design as a task of virtual product development and to assist the process simultaneously through the use of appropriate digital models and virtual methods. This paper reports on R&D results concerned with integration of the process of conceptual design based on traditional aids, such as freehand paper sketches, in virtual environments. Until now, it has not been possible to work iteratively with both freehand sketches and digital product models. This paper describes how to interpret product descriptions in freehand sketches and to transfer them to digital three-dimensional models, e.g. in order to visualize, calculate and evaluate shapes to the development of computer-aided design (CAD) models. The methods combine an image-based modeling strategy with conventional CAD modeling strategies.

Study on shape creation of building's roof by evaluating aesthetic sensibility

The purpose of this study is to develop an optimum design method for roof shapes satisfying both aesthetic sensibility (beauty) and economic evaluation by using the genetic algorithm (GA). The object is the roof of a gymnasium, and the target roof shape is asymmetrical. The roof shapes were evaluated on the basis of the satisfaction degrees of both economic evaluation and beauty. The economic evaluation used stress evaluation values that were obtained by the finite element method analysis. The KANSEI (equal to aesthetic sensibility) evaluation values were calculated from the learned results of the questionnaire by a neural network. Each satisfaction degree is calculated by membership functions. The synthetic satisfaction degree is calculated by fuzzy theory by using both the stress satisfaction degree and the KANSEI satisfaction degree. The roof shape, which has the highest synthetic degree of satisfaction, is created by the GA. A beautiful shape, which was not created only by the stress evaluation, was created by also considering the beauty evaluation.

1205 イメージ運動モデルによる製品イメージの創造(OS12-2 感性・感情と設計)

In industrial design process, visual imagery and "schema" play important roles to create new product shape. Image movement model as a model of industrial design process based on visual imagery is proposed. Concept of product shape creation system based on image movement model is proposed. Methods for product shape creation system are proposed and implemented.

3120 調和振動子群を用いた空間モデルによる形状創成(S59-2 ヒューマンインタフェース(2),S59 ヒューマンインタフェース)

3120 調和振動子群を用いた空間モデルによる形状創成(S59-2 ヒューマンインタフェース(2),S59 ヒューマンインタフェース)

Viewpoint 4

Viewpoint 4

Free-form sketching with variational implicit surfaces

With the advent of sketch-based methods for shape construction, there's a new degree of power available in the rapid creation of approximate shapes. Sketch [Zeleznik, 1996] showed how a gesture-based modeler could be used to simplify conventional CSG-like shape creation. Teddy [Igarashi, 1999] extended this to more free-form models, getting much of its power from its ``inflation'' operation (which converted a simple closed curve in the plane into a 3D shape whose silhouette, from the current point of view, was that curve on the view plane) and from an elegant collection of gestures for attaching additional parts to a shape, cutting a shape, and deforming it. But despite the powerful collection of tools in Teddy, the underlying polygonal representation of shapes intrudes on the results in many places. In this paper, we discuss our preliminary efforts at using variational implicit surfaces [Turk, 2000] as a representation in a free-form modeler. We also discuss the implementation of several operations within this context, and a collection of user-interaction elements that work well together to make modeling interesting hierarchies simple. These include ``stroke inflation'' via implicit functions, blob-merging, automatic hierarchy construction, and local surface modification via silhouette oversketching. We demonstrate our results by creating several models. Categories and Subject Descriptors (according to ACM CCS): I.3.5 [Computer Graphics]: Modeling packages I.3.6 [Computer Graphics]: Interaction techniques