基于ABF的自由曲面上三维复杂图案的雕刻方法  

An ABF-based Method for 3D Complex Pattern Sculpting on Free-form Surfaces

作　　者：徐金亭[1] 汪顺可[1] 张向奎[1] 

机构地区：[1]大连理工大学工业装备结构分析国家重点实验室,大连116024

出　　处：《机械工程学报》2013年第3期137-144,共8页Journal of Mechanical Engineering

基　　金：国家自然科学基金(51105058);国家自然科学基金重大(11290143)资助项目

摘　　要：利用五轴数控机床在自由曲面上快速生成美观的图案在珠宝纹饰雕刻、吹塑/挤压模具图案制作、复杂产品外观图案的自动喷绘等方面具有潜在的广泛应用。针对目前图案映射对单一参数曲面参数域处理的依赖,提出一种可应用于复合裁剪曲面、网格曲面甚至点云曲面的三维复杂图案雕刻方法。利用图像边界处理技术,将二维的数字图案转化为可用于数控加工的离散点集。进而根据保角映射(Angle-based flattening,ABF)原理,将目标曲面映射到二维平面域,建立三维曲面与二维平面域之间的一一映射关系。以此映射为向导,提出基于面积坐标的线性映射方法,将离散图案逆映射到目标曲面上。根据选择的刀具参数及给定的切削深度,生成用于三维复杂图案雕刻的刀具轨迹,并进行雕刻仿真试验和实际雕刻加工试验。试验结果证明,所提方法简单实用,能够在复杂自由曲面上生成美观的雕刻图案。Sculpting pattern onto free-form surfaces in five-axis CNC machine tools is a potential method for many applications such as jewelry, glass blow-molding, injection molding, even automatically spray painting on the surfaces, etc. Since traditional methods map the pattern placed in parameter domain onto the part surface by using the surface equation, this may not be feasible for multiple trimmed surfaces, mesh surfaces and cloud of point surfaces. An angle-based flattening （ABF） based method for pattern sculpting on free-form surfaces is developed. 2D pattern is converted into discrete data points for tool path generation from digital image using image boundary processing technique. To map the discrete pattern onto the part surface, ABF is introduced, which is used for flattening the part surface onto 2D plane. Using this mapping of the part surface to 2D region, a linear mapping method is proposed to inversety map the pattern onto the part surface. On basis of this, according to the setected cutter parameters and the dep~ of cut, tool path for pattern sculpting is generated. Simulation and real machining is implemented on several sample surfaces and experimental results demonstrate the validity of the proposed method.

关 键 词：自由曲面 图案雕刻 刀具轨迹 

分 类 号：TP391[自动化与计算机技术—计算机应用技术]