Cutting force and chatter stability analysis for PKM-based helical milling operation
Cutting force and chatter stability analysis for PKM-based helical milling operation
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基于 PKM 的螺旋铣削加工的切削力和颤振稳定性分析
DOI：
10.1007/s00170-020-06252-3
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发表时间：
2020
期刊：
影响因子：
--
通讯作者：
Ji Yan
中科院分区：
文献类型：
--
作者：
Shi Mengrui;Qin Xuda;Li Hao;Shang Shuai;Ji Yan
为了提高制造生产率，工业机器人移动的加工被提出作为一种经济有效的和便携式的制造替代大型数控机床在飞机零件加工。结合螺旋铣削和并联机器人的优点，研究了一种新型五自由度混联并联机床（TriMule）螺旋铣削加工的切削力和颤振稳定性。建立了并联机床螺旋铣削加工的切削力和动力学模型，采用完全离散化的方法，采用欧拉法得到了7个典型加工位置的颤振稳定性图。以钛合金螺旋铣削加工为例，对预测的切削力和颤振稳定性图进行了实验验证。研究发现，在螺旋铣削加工中，PKM的加工位置对相应的极限稳定轴向切削深度有很大的影响。同时指出，主轴转速是影响螺旋铣削不同加工位置稳定性差异的重要因素。同时，当主轴转速高于1000 rpm时，在前4阶切削系统模态下，螺旋铣削稳定性仅由TriMule的二阶、三阶和四阶模态决定。研究结果可为螺旋铣削参数优化和机器人加工位置的合理选择提供依据。
In order to enhance the manufacturing productivity, mobile machining with industrial robots is proposed as a cost-effective and portable manufacturing alternative to large-scale CNC machine tools in aircraft part machining. Combing the advantages of helical milling and parallel robot, the cutting forces and chatter stability of a novel 5-DOF hybrid PKM (named TriMule)-based helical milling process are first investigated in this paper. The cutting force and dynamic model of PKM-based helical milling operation are proposed, and the chatter stability diagrams at the seven representative machining positions are obtained based on the complete discretization scheme with Euler’s method approach. The predicted cutting forces and chatter stability diagrams are experimentally validated by the PKM-based titanium alloy helical milling. It can be found that the PKM machining position has a great influence on the corresponding limit stable axial depth of cut in the helical milling operation. Meanwhile, it was indicated that the spindle speed is an important factor affecting the helical milling stability difference at different machining positions. Meanwhile, it was found that the helical milling stability is only determined by second-, third-, and fourth-order modes of TriMule when the spindle speed is higher than 1000 rpm with the first 4 modes of the cutting system considered. The research results are expected to provide a basis for the helical milling parameter optimization and reasonable robot machining position selection.