Yuan Wei, Cheung Chi-Fai
State Key Laboratory in Ultra-Precision Machining Technology, Department of Industrial and Systems Engineering, The Hong Kong Polytechnic University, Hong Kong 999077, China.
Micromachines (Basel). 2021 Nov 26;12(12):1448. doi: 10.3390/mi12121448.
Previous models of the relative tool-work vibration are not generalized to represent the surface generation mechanism in the ultra-precision tool servo-based diamond cutting (UTSDC) of three-dimensional (3D) microstructured surfaces. This is due to the fact that the tool-work vibration in UTSDC is no longer a steady harmonic vibration with a constant amplitude but is influenced by the tool motion along the thrust direction. In this paper, dynamic modeling of the cutting system is presented for the characterization of surface topography variation in UTSDC of a microlens array considering the tool-work vibration as an underdamped vibration. The natural frequency and damping ratio of the cutting system are determined by the data-dependent systems (DDS) method. Based on the analysis of the surface profile and cutting force signals, it is found that the tool-work vibration is significantly enhanced in the cut-in process when the cutting speed increases. The simulation results show that the proposed dynamic model can well-determine root-mean-squares RMS values of the surface primary profile and the dynamic force acting on the force sensor. The dynamic model provides insight into the formation of the surface topography variation in UTSDC of 3D microstructured surfaces, and the model might be applied in self-optimized machining systems in the future.
先前的相对刀具-工件振动模型并未得到推广，无法用于描述基于超精密刀具伺服的三维（3D）微结构表面金刚石切削（UTSDC）中的表面生成机制。这是因为UTSDC中的刀具-工件振动不再是具有恒定振幅的稳态谐波振动，而是受到刀具沿推力方向运动的影响。本文针对微透镜阵列的UTSDC，考虑刀具-工件振动为欠阻尼振动，建立了切削系统的动力学模型，以表征表面形貌变化。切削系统的固有频率和阻尼比通过数据相关系统（DDS）方法确定。通过对表面轮廓和切削力信号的分析发现，当切削速度增加时，刀具-工件振动在切入过程中会显著增强。仿真结果表明，所提出的动力学模型能够很好地确定表面原始轮廓的均方根（RMS）值以及作用在力传感器上的动态力。该动力学模型为深入了解3D微结构表面UTSDC中表面形貌变化的形成过程提供了依据，该模型未来可能应用于自优化加工系统。
