Machining environment measurement device

A machining environment measurement device for measuring an influence of a vibration on a machining process in a machine tool, the machining environment measurement device comprising:

• a reference machining data storage unit configured to store reference machining data computed on the basis of time-series data of vibration measured in advance in an ideal machining environment;
• a data acquisition unit configured to acquire time-series data of vibration of at least a holder attached to a spindle of the machine tool, wherein the vibration of the holder is detected by a holder measurement sensor;
• an analysis unit configured to
• analyze the time-series data acquired by the data acquisition unit and
• compute feature data indicative of a feature of the time-series data;
• a comparative determination unit configured to
• perform a comparison that compares
• (a) a distance Di between (1) parameters at a first frequency Si among frequencies included in the feature data indicative of the feature of the time-series data computed by the analysis unit and (2) the parameters at a second frequency Fi corresponding to the first frequency and included in the reference machining data stored in the reference machining data storage unit, with
• (b) predetermined thresholds,
• compute a score Xi for the frequencies Si and Fi on the basis of a result of the comparison,
• compute an average of the scores given to all the frequencies included in the feature data, as a score X of the time series data, and
• based on the score X of the time series data, make determination of a machining environment of the machine tool;
• and
• a display unit configured to display a result of the determination made by the comparative determination unit,
• wherein the comparative determination unit is further configured to
• determine the distance Di between the parameters at the first frequency Si and the parameters at the second frequency Fi according to Equation (1) below while assigning a weight to the square of the difference between the parameters:
• DISTANCE Di BETWEEN Si AND Fi=√{square root over ((FAi−SAi)2(FVi−SVi)2+(FDi−SDi)2)} (1), and
• determine the score X of the time series data according to Equation (2) below:
• SCORE
• ×
• OF
• ⁢
• ⁢
• TIME
• ⁢
• ⁢
• SERIES
• ⁢
• ⁢
• DATA
• =
• 1
• n
• ⁢
• ∑
• Xi
• ,
• (
• 2
• )
• where SAi, SVi and SDi are first through third parameters, respectively, at the first frequency Si, and FAi, FVi and FDi are the first through third parameters, respectively, at the second frequency Fi.