A New Local Control Spline with Shape Parameters for CAD/CAM

来源 :Journal of Computer Science and Technology | 被引量 : 0次 | 上传用户:youjia88
下载到本地 , 更方便阅读
声明 : 本文档内容版权归属内容提供方 , 如果您对本文有版权争议 , 可与客服联系进行内容授权或下架
论文部分内容阅读
A new local control spline based on shape parameters with G~2 continuity,called BLC-spline,is pro-posed.Not only is BLC-spline very smooth,but also the spline curve’s characteristic polygon has onlythree control vertices,and the characteristic polyhedron has only nine control vertices.The behavior of lo-cal control of BLC-spline is better than that of the other splines such as cubic Bezier,B andBeta-spline.The three shape parameters β_0,β_1 and β_2 of BLC-spline,which are independent of the con-trol vertices,may be altered to change the shape of the curve or surface.It is shown that BLC-splinemay be used to construct a space arc spline for DNC machining directly.That is a powerful tool forthe design and manufacture of curves and surfaces in integrated CAD/CAM systems. A new local control spline based on shape parameters with G ~ 2 continuity, called BLC-spline, is pro-posed. Not only BLC-spline very smooth, but also the spline curve’s characteristic polygon has onlythree control vertices, and the characteristic polyhedron has only nine control vertices. The behavior of lo-cal control of BLC-spline is better than that of the other splines such as cubic Bezier, B and Beta-spline. The three shape parameters β_0, β_1 and β_2 of BLC-spline, which are independent of the con-trol vertices, may be altered to change the shape of the curve or surface. It is shown that BLC-splinemay be used to construct a space arc spline for DNC machining directly. manufacture of curves and surfaces in integrated CAD / CAM systems.
其他文献
1996年4月27日 ,具有相当读者群的《华商时报》刊登了中国人民大学舆论研究所的一项调查 ,调查显示 :“廉政和清除腐败”被列为1996年中国工人最关心的十大问题之首。面对社会进步、经济
In object-oriented database systems(OODBSs),the traditional transaction models are no longer suit-able because of the difference between the object-oriented da
根据党的十五大提出的关于加强党的组织建设的目标和任务,结合辽宁省气象部门实际,为积极推进全省气象事业发展和气象业务现代化建设提供人才保证,人事工作要努力在各级领导班子
本文研究了添加石灰(CaCO_3),有机物料(稻草、苕子)后酸性土壤 Cd 活性变化以及淹水,培养时间对酸性土壤 Cd 的活性影响。结果表明,施用石灰、有机物料后,酸性土壤 pH 上升,
从去年起 ,山东省济南市工商局长清分局逐步完善各项措施 ,不断增强政务公开透明度 ,巩固扩大政务公开带来的成果 ,在全局创造一个依法行政 ,廉洁高效的环境 ,有力地促进了各
近年来,我区一些地方群众集体上访甚至越级上访的事件时有发生,不仅群众自身的正常生产和生活受到影响,而且增加了社会不稳定因素。如何改变这种状况?我们的做法是:变群众上访为领
患儿: 女, 3岁4个月. 因发热、咳嗽2 d, 左侧胸痛伴呼吸困难1 d入院. 既往健康. 入院前2 d受凉后咳嗽伴中度发热, 咯少量白色泡沫痰, 在当地医院儿科诊断为"上呼吸道感染", 给予抗感染和对症等治疗. 1 d前剧烈咳嗽后出现左侧持续胸痛伴呼吸困难, 摄胸片示左侧胸腔内巨大液气平, 纵隔明显右移, 以"左侧脓气胸"转入外科, 麻醉下行左侧胸腔穿刺, 抽出少许灰白色混浊液后, 行左侧胸腔
跳远和其他田径运动项目一样,除了要遵循训练原则外,还有明显的专项特点,即要求运动员熟练、正确地掌握跳跃技术。因此,快速助跑和快速起跳是提高一系列技术动作的前提,根据
目的:对3种纯化膨润土的粉体学性质进行初步考察,为片剂制剂工艺的选择提供可供参考的数据。方法:根据文献方法考察粒度分布、松密度、摇实密度、休止角和粉末成型性,以川北
本文采用胶体分散法研究我国自北而南的13个地带性土壤中有机矿质复合体的组成、形成因素及其结合特点等。结果表明:复合体总量(G_0+G_1+G_2)与土壤中粘粒含量呈显著正相关。