曲面数控加工中刀具轨迹生成探讨

以三坐标数控加工自由曲面为研究对象,对复杂曲面刀具路径生成中的一些问题进行了探讨,对常用的三坐标曲面加工方法进行分析比较,给出了步长、步距的计算公式以及走刀方式、进/退刀方式的选择原则.     

自由曲面数控加工刀具轨迹优化算法的研究

提出了一种数控加工刀具轨迹排列优化算法,使相邻加工轨迹间的残留高度都等于最大允许值,在保证精度的前提下,刀具轨迹排列更加合理,轨迹条数和轨迹长度大大减小,加工效果明显提高。     

自由曲面数控加工刀具轨迹曲线的一种生成算法

提出一种自由曲面数控加工轨迹曲线计算方法。根据这一方法,可由自由曲面上一定数量的任意分布型值点来 计算曲面加工时的刀具曲线。算法的基本思想是,型值点影响并决定着其控制区域内的曲面形状,这种影响的大小与到 型值点的距离及权指数相关。分别给出了沿X向进给及Y向进给时刀具轨迹曲线的生成算法。讨论了算法中参数选取 对加工曲面形状及拟合精度的影响。     

自由曲面数控加工刀具的研究

对自由曲面数控加工中的刀具进行了较深入的研究。从刀具有效半径和切削速度的角度,对平头立铣刀在五坐标自由曲面加工中的加工效率与切削性能进行了分析。提出了球头刀和平头刀的刀位计算方法,并对叶片曲面的刀具轨迹进行了仿真模拟。     

自由曲面数控加工刀具轨迹映射算法

对自由曲面的数控加工,寻求最优的刀具轨迹生成方法至关重要.本文基于开源3D库Open CASCADE(OCC)和编程开发环境Microsoft Visual Studio 2010(VS2010),应用B样条表达的自由曲面,采用投影法思想,研究重用已有相似刀具路径方法,提出了处理自由曲面的NC刀具轨迹映射算法....     

曲面造型及数控加工刀具轨迹生成方法的研究

依据双三次均匀B样条曲面造型理论 ,运用等参数线加工方法 ,给出一种较为简便的曲面造型及数控加工刀具轨迹的生成方法     

自由曲面NC加工无干涉刀具轨迹生成

对自由曲面ＮＣ加工中的干涉情况和现有处理方法进行分析，以曲面模型→刀具接触点数据→无干涉刀位数据为基本求解策略。综合多种优化措施，设计一个完整与高效的无干涉刀具轨迹生成算法并在微机上成功地实现。     

带倒角平底刀曲面加工干涉刀具轨迹生成

对自由曲面ＮＣ加工中刀具轨迹生成技术和干涉处理方法进行了分析,以同面模型→刀具接触点数据→无干涉刀位数据为基本求解策略,研究开发出适用于带倒角平底刀无干涉刀具轨迹生成的新算法。该算法具有干涉检测彻底、处理效率高、稳定性好等优点。     

自由曲面加工中数控加工技术的应用

随着我国加工制造业的快速发展,自由曲面加工产品的需求量逐年上升,这必然对其数控加工技术的要求越来越高。本文基于上述背景,以重用已有相似刀具轨迹为基本方法来进行其刀具轨迹模拟,以OCC以及VS2010为编程开发环境,初步设计了其刀具轨迹生成系统,并且最后进行了自由曲面数控加工的仿真设计工作,以期通过仿真实验的方式来进一步分析其刀具轨迹重用的合理性与科学性。     

浅析自由曲面数控加工中刀具路径规划

复杂曲面广泛应用于航空、汽车、电子等行业,所以加工制造业对于自由曲面数控技术要求越来越高,而刀具路径规划是负责曲面加工过程中关键技术之一.本文在刀具路径规划技术发展基础上,对自由曲面数控加工中刀具路径规划问题进行了分析.     

自由曲面五轴变步长数控加工刀轨生成方法

为了在满足逼近误差要求的同时最大程度减少冗余刀轨,对自由曲面提出了一种五轴变步长数控加工刀轨生成方法.首先对刀触点轨迹基于线性误差计算出初始刀触点点集,再以局部干涉调整前倾角的方式计算出无干涉刀位点和刀轴矢量;以最大非线性误差刀位处到刀触点轨迹的最小值作为相邻刀位点之间的逼近误差,并基于数据点自适应离散法计算逼近误差;...     

Iso-parametric tool path generation from triangular meshes for free-form surface machining

The polyhedral model is widely used in the manufacturing industry. However, apart from the iso-planar method, the tool path generation methods for polyhedral machining are very limited. In such a case, the given tool paths are no longer boundary-conformed or efficient. This paper presents a new approach to iso-parametric tool path generation for triangular meshes. The strategy proposed herein first parameterizes the triangular faces via a harmonic map. The cutter-contact (CC) points and the path interval are then calculated based on the machining tolerance requirements and the iso-parametric tool paths are finally generated. The method is implemented on a computer and some illustrative examples are provided to show the effectiveness of the developed algorithm. The main advantage of the proposed method is that the tool paths can be generated naturally along the boundary of a polyhedral model, thus eliminating internal tight-radius corners in conventional paths. This leads to substantial reductions of tool wear and machining time. In addition, the proposed method can also be used in other non-iso-parametric tool path planning methods for triangular meshes and compound surfaces machining.     

自由曲面数控加工动态仿真研究

在VC++6.0平台上采用OpenGL技术开发一种自由曲面数控加工过程仿真系统。该系统可根据自由曲面的不同造型,规划出适当的刀位轨迹,生成G代码;实现交互控制,完成设计曲面的成型加工,并动态显示加工路径。     

基于Hilbert填充曲线的自由曲面刀具路径规划研究

利用平面Hilbert填充曲线生成方法简单、易于控制填充疏密的优点,将其用于了自由曲面数控加工刀具路径的生成.对平面Hilbert填充曲线的生成原理进行了研究,用矩阵运算的方法生成该曲线.结合自由曲面的形成过程,提出将平面Hilbert曲线通过与曲面参数域相对应的方法映射到曲面上,进而生成加工刀具路径的思想.最后用一个具体应用实例验证了生成平面Hilbert曲线方法的正确性,和用此曲线作为数控加工刀具路径的可行性.通过与经典刀具路径生成方法比较可见该方法具有算法简单,加工余量均匀,加工效率与表面质量高的优点.     

The implementation of adaptive isoplanar tool path generation for the machining of free-form surfaces

Machining of steep regions is an important research topic in the machining of free-form surfaces. A new tool path generation algorithm to adaptively machine free-form surfaces has been recently developed. However, similarly to many newly emerged methods, so far it has not been used in industry because no commercial platform is currently available and the user-developed system is not robust enough for industrial applications. To solve this problem, this paper presents a new implementation method by integrating it in a commercial CAD/CAM system (Pro/Engineer). With this strategy, other than conducts detailed computations for parameters, such as scallop heights and forward steps, or designing the non-cutting functions such as engaging and retracting methods, which are routines in every tool path generation process, the implementation utilizes existing tool path generation templates in Pro/E to generate the required tool paths. This makes the tool path generation process easier and the tool paths generated more practicable because the integration is relieved of the time-consuming routine calculation and the entire cutting and non-cutting functions in the commercial system are transparent to users. Based on the API of Pro/E, the new tool path generation method was successfully implemented and cutting tests were conducted. Not losing generality, the implementation could also be conducted in other commercial systems as similar templates are available in these systems as well.     

空间自由曲面五轴联动数控加工

介绍了五轴数控机床的运动方式,阐述了空间自由曲面五轴联动数控加工中刀具路径规划的基本方法:参数线法、CC路径截面线法、CL路径截面线法、导动面法等。之后对五轴加工中刀具轴向规划进行了论述:垂直于表面方式、平行于表面方式、倾斜于表面方式。最后归纳总结了刀具干涉的检测与处理的方法,并分别说明了其优缺点和适应范围。     

Mesh-based tool path generation for constant scallop-height machining

This paper presents a new approach to mesh-based tool path generation for obtaining constant scallop heights. The mesh surface has recently become the focus of considerable interest, because its geometric computation is simpler and more robust than that of the parametric surface. These advantages make it easy to check and remove interference in the process of tool path generation. The previous tool path generation method based on the mesh surface, however, can generate only one topology of iso-planar type where tool paths have evenly spaced tool path intervals. As constant scallop heights cannot be obtained from evenly spaced tool path intervals, unevenly spaced tool paths based on offset meshes are necessary for reducing the machining time and for easy interference removal. This paper proposes and compares four methods to estimate curvatures from the mesh surface; the curvature is essential for calculating unevenly spaced tool path intervals. This paper also proposes an improved drive surface method to propagate CL-paths unevenly and to generate tool paths with various topologies.     

离散数据曲面的三轴数控粗加工代码生成算法

介绍一种用于离散数据的三轴数控粗加工代码生成算法。该算法以离散数据点为输入信息,先构建一个网格曲面,然后通过一系列的计算步骤,最终得到用于实现离散数据曲面粗加工的数控代码。详细阐述该算法的推导过程,并给出算法的实现细节。该算法被证明具有良好的使用价值。     

自由曲面加工中考虑干涉的刀具路径安排

研究了自由曲面加工中无干涉刀具路径的安排,推出了一种创新的干涉检查方法,将干涉检查和加工刀具路径安排分别进行,加快了数控加工过程,提高了精度,并将该方法应用于三种常用的刀具体,通过实例验证了本法的合理性.规划刀具路径时,先按照某个参数方向的曲率半径和最大弦偏差确定加工步长,然后再按照另一个参数方向的曲率半径和残瘤高度来确定相邻两条刀具路径间的加工步距,最后跳过识别出的干涉区域安排加工路径.