用AR模型分析铣削加工过程的稳定性

以时间序列与系统分析理论为基础，通过建立实测铣削信号的ＡＲ（ｎ）自回归系统模型，系统研究了铣削过程中振动能量与切削状态的关系以及各振动模态的阻尼变化与初削状态的定关系。试验分析表明：在不同的切削状态下，铣削振动系统总的振动能量基本上保持不变；而铣削振动系统的结构薄弱模态所占有的能量和振动阻尼则随系统切削状态变化而波动较大，且有突发现象。两者皆可以作为定量分析和识别铣削加工过程稳定性的重要特征量。

STABILITY ANALYSIS OF MILLING PROCESS BY TIME SERIES

his paper is based on the theory of time series and system analysis. Through the setting-up of the AR (n) autoregressive model of actual milling signal obtained, the relation between vibration energy and cutting states, and the qualitative relation between damping changes of every vibration model and cutting states are studied systematically. The experimental analysis shows that, under different cutting states, total vibration energy keeps basically unchanging, but, with the change of cutting state, the energy which structural weak links of milling vibration system prosseses and dampings of structural weak links may have a large undulation or an abrupt increase. Both of them may be considered as important characters quatitatively to analyse and identify the stability of milling process.