基于积极体验的参数化产品设计模型

目的 构建一种基于积极体验的参数化产品设计模型.方法 首先,以文献研究为基础,通过理论分析法,界定积极体验与参数化产品设计概念与现状;其次,以积极体验为依据,以参数化设计流程为基础,构建基于积极体验的参数化产品设计的一般框架;接下来,通过设计实践法,对该设计框架进行设计实践;最后,从积极界定、图像生成、参数设计与方案产出的角度,分析并讨论设计结果.结论 提出了一种基于积极体验的参数化产品设计模型,包括积极界定、图像生成、参数设计、方案产出四部分,即通过积极界定,提取产品背后的积极意义;通过图像生成,抽象积极要素并可视化肌理;通过参数设计,让用户参与调整产品参数;通过3D打印技术产出设计结果.这有助于设计师利用该参数化产品设计框架提升用户的积极体验,乃至主观幸福感.     

基于参数化思维的产品创新设计方法

目的 提出基于参数化思维的产品创新设计方法。针对产品的概念设计阶段,利用参数化的设计思维方法,来创造可以激发设计师灵感的设计环境,启发其更好地进行产品创新设计。方法 依据设计需求对产品进行功能特征的描述与分析,初步确定各功能部件的位置、结构、尺寸等设计参数后,对造型生成进行逻辑推演,在Rhinoceros与Grasshopper组成的参数化设计平台中选定算法并生成造型,最后通过对整体方案的分析、评估及参数化调整,来确定创新性的设计方案。结果 基于参数化思维的产品创新设计方法可有效帮助设计师进行思维发散,设计方案优化程度高、可行性强、拓展空间广,符合理论与实践需要。结论 在工业设计领域,基于参数化思维的产品创新设计方法可弥补传统设计方法的不足,使产品设计更具高效性和创新性,是一种行之有效的产品设计方法。     

基于参数化的个性3D打印产品设计研究

目的 基于用户调研,研究参数化设计结合3D打印技术在个性化智能手环表带定制设计的可行性.方法 首先阐释了国内外参数化设计研究的现状,通过解析参数化风格和相关产品案例明晰了参数化与产品设计的关系,进而总结了参数化个性定制的内涵;通过用户调研提出了参数化设计中参数的获取及参数逻辑关系建立的设计流程和设计任务;通过Rhino软件中Grasshopper的参数建模功能,从用户需求着手完成了设计实践,最终打印了3D实物模型,完成了对设计方案的评价.结果 基于用户参与情境下的参数化设计,在产品开发流程及方案呈现中能较好地体现个性化的用户需求.结论 参数化设计体现了个性化产品的设计思想,借助3D打印等增材制造技术,让这一效果得到了强化.参数化设计中的个性体现取决于数据的获取和数据逻辑关系的构建,而这可以从用户调研的结论中进行总结和提取.参数化设计、3D打印技术与个性化需求三者缺一不可,既互为驱动又相互制约.     

基于Web的框架木箱CAD系统开发与实现

利用VB语言对Solidworks软件进行二次开发,完成框架木箱的参数化设计,在本地参数化设计系统的基础上,利用PHP语言,并结合MySQL数据库,进一步实现了基于Web的框架木箱CAD系统。详细介绍了系统的整体结构框架以及实现过程中的关键技术,用户只要访问网站输入基本参数,即可生成符合要求的木箱模型,并能进行浏览及下载,从而实现了框架木箱设计的共享化与快捷化。     

基于实景三维的城市道路实体参数化建模研究

为解决现有道路实体三维模型建模存在局限几何拓展层面、建模规则不易重用等问题,在此基础上,对基于真实场景的城市道路参数化模型进行研究。利用三维激光扫描技术,对道路进行抽象描述并提取参数。在此基础上,通过构建路网,将三维实体模型和场景融合,完成道路的参数化表示。最后,通过基于多层次空间语义约束的建模、多层次空间语义约束规则制定,生成道路实体模型。该研究为更直观地展示城市道路实景三维模型、丰富模型信息提供技术支撑。     

基于参数化设计的传统纹样结构衍生及应用

目的 将传统纹样的形式规则与参数化设计方法相结合,探索传统纹样在现代设计中的衍生设计方法,为纹样文化的传承和发展提供新的思路。方法 提取传统纹样造型中的构图规则,利用现代图形设计中的函数曲线、曲线的控制点坐标参数,重构参数纹样模型。通过空间点集的形式构建纹样的空间排列结构。制定演变规则,调整可变参数,对目标纹样进行结构衍生设计。结果 以马家窑旋涡纹为例,分析并提取结构规则,在此基础上,利用参数化建模工具Grasshopper完成参数纹样建模和插件制作以及参数化纹样设计和应用。结论 传统纹样结构蕴含着有序的形式规则,具备纹样参数化设计的基本条件。构建的参数化纹样结构可更灵活高效地进行纹样衍生和设计,有利于传统纹样与现代设计的融合。     

基于Pro/E的货车转向架参数化设计系统的研究

将参数化设计技术应用于货车转向架的设计,通过设计参数来驱动转向架零部件的几何模型,简化生成和修改零部件模型的操作。在现有计算机辅助设计软件的基础上,运用其二次开发工具、面向对象的程序设计语言、数据库技术及其编程接口进行二次开发,实现了基于参数化设计技术的货车转向架设计系统,提高了货车转向架设计的速度和质量。     

基于UG参数化设计系统的研究

论文是以功率超声珩磨装置的参数化建模为例,在一般零件参数化设计的基础上,提出了一种基于草图装配和草图约束的参数化设计方法。此方法是利用UG建模里的草图功能,在对零件模型进行几何约束和尺寸约束的基础上,用函数表达式建立多个零部件的变量尺寸与装配草图的关系,通过对装配草图里设计变量尺寸的管理,实现整个装置零部件之间的联动。     

传统服饰纹样生成设计研究

目的 服饰是我国文化创新的主要领域,也是展示文化的主要途径。通过二维服饰传统纹样向三维实体首饰及穿戴产品的转化生成,突破以往服饰纹样在平面维度生成、衍生的局限性。方法 基于边缘检测等图像学技术结合人工描摹,实现二维传统服饰纹样图像的抽象化提取;运用人工神经网络的机器学习算法与图形学算法,训练一个传统纹样轮廓线的自动生形模型,生成三维首饰形态,并由服饰纹样二维图像生成三维参数化肌理。结果 以传统服饰吉祥纹样为例,形成纹样素材库,在此基础上,实现平面纹样提取、三维形体转化、三维肌理转化、肌理向形体映射的生成设计路径,通过应用软件系统的设计实践验证其可行性。结论 建立传统服饰文化元素的现代服饰产品形态转化及个性化定制路径,解决传统文化与现代消费、现代产业之间的割裂问题,从现代增材制造工艺、材料、理念等方面促进服饰产业的结构优化与转变,为其注入新的力量,对民族服饰文化的保护和传承具有重要的价值和意义。     

基于感性工学的产品质感调和设计模型研究

目的运用感性工学和BP神经网络构建产品质感调和设计模型。方法通过多维尺度分析和聚类分析,分析出了最适合于描述质感调和的代表性感性意象词汇集;通过统计分析,确定了以透明度、光泽度和粗糙度及其细分类目为元素的质感调和空间;通过质感调和实验,获得了针对实验样本的质感空间特征值和感性评价值;最后通过MATLAB的BP神经网络工具箱,建立了基于感性意象的质感调和设计BP模型,并重新设计检验样本论证了模型的可靠性。结论该模型为后续的计算机辅助质感调和设计系统提供了理论和算法依据,可以提高产品设计的成功率。     

Texture‐based parametric active contour for target detection and tracking

In recent years, active contour models (ACM) have been considered as powerful tools for image segmentation and object tracking in computer vision and image processing applications. This article presents a new tracking method based on parametric active contour models. In the proposed method, a new pressure energy called “texture pressure energy” is added to the energy function of the parametric active contour model to detect and track a texture target object in a texture background. In this scheme, the texture features of the contour are calculated by a moment‐based method. Then, by comparing these features with texture features of the target object, the contour curve is expanded or contracted to be adapted to the object boundaries. Experimental results show that the proposed method is more efficient and accurate in the tracking of objects compare to the traditional ones, when both object and background are textures in nature. © 2009 Wiley Periodicals, Inc. Int J Imaging Syst Technol, 19, 187–198, 2009     

基于双参数颗粒分析的纹理分割

形态学颗粒分析是一种有效的颗粒纹理图像分割方法,但由于单一的颗粒度参数,使得其难以分割如颗粒度相同而空间排列不同的纹理图像,为此提出了一种基于双参数颗粒分析的纹理图像分割方法,该方法将传统的颗粒分析从单一参数扩展到以颗粒度和空间位置为参数的二维空间,使得扩展后的颗粒分析通过分布函数不仅能够提取纹理的颗粒度特征,而且能够获取纹理的空间排列特征,克服了传统颗粒分析难以区分颗粒度相同而空间排列不同纹理区域的问题.仿真实验表明,该方法在运算复杂度增加不大的情况下,纹理分割效果优于颗粒分析法,区域像素错分率低于颗粒分析法和Gabor滤波器法.     

Homogenization‐based design of surface textures in hydrodynamic lubrication

An optimization framework is developed for surface texture design in hydrodynamic lubrication. The microscopic model of the lubrication interface is based on the Reynolds equation, and the macroscopic response is characterized through homogenization. The microscale setting assumes a unilateral periodic texture but implicitly accounts for the bilateral motion of the surfaces. The surface texture in a unit cell is described indirectly through the film thickness, which is allowed to vary between prescribed minimum and maximum values according to a morphology variable distribution that is obtained through the filtering of a design variable. The design and morphology variables are discretized using either element‐wise constant values or through first‐order elements. In addition to sharp textures, which are characterized by pillars and holes that induce sudden transitions between extreme film thickness values, the framework can also attain a variety of non‐standard smoothly varying surface textures with a macroscopically isotropic or anisotropic response. Copyright © 2016 John Wiley & Sons, Ltd.     

Parametric shape and topology optimization: A new level set approach based on cardinal basis functions

The parametric level set approach is an extension of the conventional level set methods for topology optimization. By parameterizing the level set function, level set methods can be directly coupled with mathematical programming to achieve better numerical robustness and computational efficiency. Moreover, the parametric level set scheme can not only inherit the primary advantages of the conventional level set methods, such as clear boundary representation and the flexibility in handling topological changes, but also alleviate some undesired features from the conventional level set methods, such as the need for reinitialization. However, in the existing radial basis function–based parametric level set method, it is difficult to identify the range of the design variables. Besides, the parametric level set evolution often struggles with large fluctuations during the optimization process. Those issues cause difficulties both in numerical stability and in material property mapping. In this paper, a cardinal basis function is constructed based on the radial basis function partition of unity collocation method to parameterize the level set function. The benefit of using cardinal basis function is that the range of the design variables can now be clearly specified as the value of the level set function. A distance regularization energy functional is also introduced, aiming to maintain the desired signed distance property during the level set evolution. With this desired feature, the level set evolution is stabilized against large fluctuations. In addition, the material properties mapped from the level set function to the finite element model can be more accurate.     

Object detetion and image segmentation using texture pressure energy in parametric active contour models

Abstract

In recent years, Active Contour Models (ACMs) have become powerful tools for object detection and image segmentation in computer vision and image processing applications. This paper presents a new energy function in parametric active contour models for object detection and image segmentation. In the proposed method, a new pressure energy called “texture pressure energy” is added to the energy function of the parametric active contour model to detect and segment a textured object against a textured background. In this scheme, the texture features of the contour are calculated by a moment based method. Then by comparing these features with texture features of the object, the contour curve is expanded or contracted in order to be adapted to the object boundaries. Experimental results show that the proposed method has more efficient and accurate segmenting functionality than the traditional method when both object and background have texture properties.     

基于质感要素的产品材质意象设计研究

目的为了探讨产品材质意象设计的有效方法,研究利用质感要素来构建材质意象评价体系。方法利用色彩理论、主成分分析法等方法,确定产品色彩、材料、表面处理工艺的质感要素、质感要素评价等级和质感要素评价系数。利用质感要素定量描述确定材质、质感要素、材质意象的数学表达式,并构建三者之间的关系模型。结果以水杯为例,利用最小二乘法确定水杯材质意象评价模型。经验证,水杯材质意象评价模型的准确率为80%。结论质感要素评价等级、质感要素评价系数为材质意象设计提供了参数化方法。产品材质意象关系模型较好地反映了材质、质感要素、材质意象之间的内在关系。利用提出的材质意象设计方法,可计算任意产品的材质意象值,为产品材质意象设计提供理论指导。     

基于Pro/E的包机槽轮机构建模及运动仿真

以包装机械中常用的外槽轮设计为例,利用PRO/E建立了槽轮机构参数化设计的数学模型,利用Pro/E的Mechanism成功实现了槽轮机构的运动仿真.提高了槽轮机构的设计效率,为槽轮机构的数字化设计、加工提供了理论依据.     

Certified real-time shape optimization using isogeometric analysis,PGD model reduction,and a posteriori error estimation

In this paper, we address the effective and accurate solution of problems with parameterized geometry. Considering the attractive framework of isogeometric analysis, which enables a natural and flexible link between computer-aided design and simulation tools, the parameterization of the geometry is defined on the mapping from the isogeometric analysis parametric space to the physical space. From the subsequent multidimensional problem, model reduction based on the proper generalized decomposition technique with off-line/online steps is introduced in order to describe the resulting manifold of parametric solutions with reduced CPU cost. Eventually, a posteriori estimation of various error sources inheriting from discretization and model reduction is performed in order to control the quality of the approximate solution, for any geometry, and feed a robust adaptive algorithm that optimizes the computational effort for prescribed accuracy. The overall approach thus constitutes an effective and reliable numerical tool for shape optimization analyses. Its performance is illustrated on several two- and three-dimensional numerical experiments.