镜像铣削加工奇异区域刀具路径优化

doi:10.7527/S1000-6893.2020.24591

Abstract

Abstract: In the mirror milling of large thin-walled parts, the discontinuous movement of the rotation axis caused by the singularity of the machine tools will reduce the milling quality and efficiency. To address this problem, this paper analyzes the cause of singularity in machining and proposes a toolpath optimization method in the singular area. First, the kinematics transformation model and the differential motion relationship of the rotation axis are derived for the milling head and support head of the mirror milling system. Based on this, the cause of the singularity and its influence on the machining quality and efficiency are analyzed, and the range of singular area is defined. Analysis shows that within the stroke of the mirror milling system, only the milling head has a singular area, but the support head does not. Then, the toolpath optimization model is established based on the toolpath smoothness index with the constraints of mirror milling. The toolpath passing through the singular area of milling head is optimized by adjusting the toolpath curve in parameter domain of machined surface to get smoother rotary axes movements, improve the machining quality and reduce machining time. Mirror milling experiment validates the effectiveness of the proposed method.

Key words: mirror milling, five-axis machining, differential motion, singularity, toolpath optimization

CLC Number:

ZHANG Shaokun, BI Qingzhen, WANG Yuhan. Toolpath optimization for mirror milling in singular area[J]. ACTA AERONAUTICAET ASTRONAUTICA SINICA, 2021, 42(10): 524591-524591.

References

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Toolpath optimization for mirror milling in singular area

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