二轴半加工系统的设计及等距线的计算  

2.5 AXIS NC SYSTEM DESIGN AND OFFSET CURVE ALGORITHM

作　　者：宋建平[1] 朱心雄[1] 

机构地区：[1]北京航空航天大学

出　　处：《图学学报》1991年第1期8-16,共9页Journal of Graphics

摘　　要：本文讨论了一个交互式的两轴半数控铣加工系统。对加工对象、加工方法及其其它功能给出了详细的讨论。系统采用了以直线、二次解析曲线、平面三次重节点非均匀有理B样条曲线构成的组合曲线,定义加工对象的边界轮廓,由其序列等距线构造加工轨迹方法。对于关键的边界轮廓等距线的计算,则以边界轮廓的基元为单位计算基元等距线,将其两两求交计算,用相应交点界定基元得到子段,并判定其有效性,按序连接有效子段,形成边界轮廓等距线。文中所讨论的方法已在APOLLO工作站和PC上实现,并得到实际应用。In this paper an interactive 2.5 axis NC system is discussed.Firstly it presents model to bemachined in the NC system,many methods machining this model and another function belongingto the NC system.After that,rules and algorithm are described by which countours of model aredefined by composited curves consisting of lines,analytical quadratic curves and plane cubic Bspline cruves,and tool path is constituted by a series of contours′ offset curves.For the systemkernl algorithm calculating offset curve,the basic ideas are the following:1)Calculate unit offsetcurve by use of contuor′s unit;2)Intersect between unit offset carves and dissect unit offsetcurve in terms of intersect points;3)Check validity of every segment;4)Link segment in accor-dance with position′s relation.All methods are implemented in APOLLO work station and PC,and are practically used.

关 键 词：等距线 边界轮廓 加工系统 子段 加工轨迹 样条曲线 加工对象 设计模块 数控铣 解析曲线 

分 类 号：TB23-55[一般工业技术—工程设计测绘]