用切削力矢量轨迹实时识别颤振状态

针对立铣加工过程中影响加工精度、效率和刀具寿命的切削颤振现象提出切削力矢量轨迹分散值评价法，并与传统的快速富里叶变换法（ＦＦＴ）进行比较．用ＦＦＴ分析时，需要预先采集大量数据，难于对机床加工过程实时控制；用切削力矢量轨迹分散值的计算方法，仅对机床主轴一个回转周期中的切削力信号进行采集，通过时域分析，快速评价机床的切削状态，可作为自动化加工过程实时监控的手段．

REAL TIME IDENTIFYING THE CHATTER BY MEANS OF TECHNIQUE OF CUTTING FORCE VECTOR LOCUS

In this paper, two approches are presented to evaluate the chatter state in end milling, because the chatter has a great influence upon the accuracy and roughness of the workpiece, the productivity and the life of the cutter. The two approaches are: (1 ) the traditional theory of Fast Fourier Transform (FFT) and (2) the technique of cutting force vector locus variance which is determined by the data from a multi-axis force sensor. The FFT is difficult to use in realtime controlling machine tools because the cutting force data of several tool rotations are required to generate the Fourier spectrum. However, the vector locus variance can be effectively applied to evaluate the chatter conditions with real-time supervision in machining process because the calculation in time domain only requires the sampling of data during one rotation of the tool.