CAJ | 학술논문

为监测数控机床主轴的运行状态，针对机床主轴在工况条件变化或故障发生时振动信号的非平稳特性，研制基于HHT时频分析方法的数控机床主轴振动监测软、硬件系统。硬件系统包括基于FPGA主控模块与PC104总线的数据采集模块；软件系统包括时域波形监测与特征数据监测两模块，其中特征数据监测模块具有监测频谱分布及时频分布功能。为更直观、准确反映数控机床主轴振动信号的非平稳特性，提出基于HHT的主轴振动信号特征提取方法，实现对振动信号时频分布的实时监测。数控机床主轴振动信号测试结果表明，该系统在监测信号时域波形与频谱分布的同时，能利用HHT的瞬时频率描述特性，实现对数控机床主轴振动信号时频分布的实时监测。
위감측수공궤상주축적운행상태，침대궤상주축재공황조건변화혹고장발생시진동신호적비평은특성，연제기우HHT시빈분석방법적수공궤상주축진동감측연、경건계통。경건계통포괄기우FPGA주공모괴여PC104총선적수거채집모괴；연건계통포괄시역파형감측여특정수거감측량모괴，기중특정수거감측모괴구유감측빈보분포급시빈분포공능。위경직관、준학반영수공궤상주축진동신호적비평은특성，제출기우HHT적주축진동신호특정제취방법，실현대진동신호시빈분포적실시감측。수공궤상주축진동신호측시결과표명，해계통재감측신호시역파형여빈보분포적동시，능이용HHT적순시빈솔묘술특성，실현대수공궤상주축진동신호시빈분포적실시감측。
A HHT-based vibration monitoring system,consisting of software and hardware system,was designed and implemented according to the non-stationary nature of the vibration signal of NC (numerical control)spindle.The hardware system concerns with the development of a data acquisition module based on FPGA and PC104 bus,and the software system includes a monitoring module of time domain wave and the counterpart of feature data.The function of feature data monitoring is divided into two parts,i.e.,the spectrum distribution monitoring and the time-frequency distribution monitoring.In order to reflect the non-stationary characteristic of the vibration signal of NC spindle more accurately,a data analysis approach,named as Hilbert-Huang transform (HHT),was introduced into the developed system.The test and analysis of the vibration signal show that the vibration monitoring system not only can characterize the time domain wave and the spectrum distribution,but also can implement the tracing of the time-frequency distribution with the help of HHT’s superiority in characterizing instantaneous frequency.