摘要 本論文研究探討高頻操作之奈米切削設備結構剛性及動態特性分析。針對奈米切削設備之挾持刀具基座、微動平台、導螺桿滑座各個結構分別單獨分析,再將次結構組合成整機予以分析,將使用有限元素法(Finite Element Method)之ANSYS軟體探討其共振頻率、模態振型、動剛度等動態特性。研究內容包括利用Block Lanczos Method進行模態分析及量測材料的自由振盪衰退率將與使用ANSYS暫態分析比較後求得阻尼係數,最後使用模態疊加法(Mode Superposition)進行簡諧分析,以驗證微動平台是否達到符合壓電致動器位移方向所需之模態振型及整機動態的結構剛性是否足夠。
Abstract The purpose of this study is to discuss the structural rigidity and dynamic analysis of high-frequency nanoscale cutting system. Nanoscale cutting system contains three substructures, includes fixed tools base, micro positioning stage and ball screw stage. ANSYS software with the finite element method is used to analyze each substructure separately and complete nanoscale cutting structure. Resonant frequency, mode shape, dynamic stiffness and dynamic analysis are investigated and discussed. Modal analysis is carried out by using Block Lanczos Method to create the model. The rate of decay of oscillation of the material is measured from the experiment. Appropriate damping coefficient is found by comparing the simulation and experimental result through transient analysis. Harmonic analysis of Mode Superposition is used to verify the displacement direction of the micro positioning stage with the chosen mode shape that is suitable to piezoelectric actuator, and the structure stiffness of the entire system is satisfactory.