axes from the Fluke 434 power quality analyser gave 3180 W, 3385 W, and 3237 W for the aforementioned angles respectively. Thus, the deviation between the model and the measured power demand of the feed axes for the specified angles were between 1% and 2%. Also presented in Figures 13 a, b, and c are power profiles for air cutting, as well as the predicted (model) and measured power demand for the feed axes of the Takisawa Mac-V3 milling machine at 3000 mm/min. Fig. 13a Power profile for Takisawa Mac-V3 milling machine during air cutting of slot at 0 degrees with feedrate of 3000 mm/min Fig. 13b Power profile for Takisawa Mac-V3 milling machine during air cutting of slot at 30 degrees with feedrate of 3000 mm/min Fig. 13c Power profile for Takisawa Mac-V3 milling machine during air cutting of slot at 90 degrees with feedrate of 3000 mm/min Predicted power requirements for feed axes at 3000 mm/min when tool is executing linear interpolation at 0, 30 and 90 were estimated to be 3189 W, 3486 W, and 3537 W respectively. The measured power of the feed axes from the Fluke 434 power quality analyser gave 3510 W, 3702 W, and 3723 W for the aforementioned angles respectively. Thus, the deviation between the model and the measured power demand of the feed axes for the specified angles were between 5 % and 9%. The wide difference in the deviation may be due to the fact that the model does not capture the dynamic characteristics of the machine tool. More acceleration forces are required to actuate the feed drive at higher feedrates which result in feed axes power requirement increase. Additionally, the energy required by the feed axes to execute a linear toolpath during air cutting can be estimated using Equation 10. Consequently, the results of some of the predicted and measured energy demand of the feed axes during air cutting are presented in Table 7. Table 7 Predicted and Measured energy demand of the feed axes
axes from the Fluke 434 power quality analyser gave 3180 W, 3385 W, and 3237 W for the aforementioned angles respectively. Thus, the deviation between the model and the measured power demand of the feed axes for the specified angles were between 1% and 2%. Also presented in Figures 13 a, b, and c are power profiles for air cutting, as well as the predicted (model) and measured power demand for the feed axes of the Takisawa Mac-V3 milling machine at 3000 mm/min. Fig. 13a Power profile for Takisawa Mac-V3 milling machine during air cutting of slot at 0 degrees with feedrate of 3000 mm/min Fig. 13b Power profile for Takisawa Mac-V3 milling machine during air cutting of slot at 30 degrees with feedrate of 3000 mm/min Fig. 13c Power profile for Takisawa Mac-V3 milling machine during air cutting of slot at 90 degrees with feedrate of 3000 mm/min Predicted power requirements for feed axes at 3000 mm/min when tool is executing linear interpolation at 0, 30 and 90 were estimated to be 3189 W, 3486 W, and 3537 W respectively. The measured power of the feed axes from the Fluke 434 power quality analyser gave 3510 W, 3702 W, and 3723 W for the aforementioned angles respectively. Thus, the deviation between the model and the measured power demand of the feed axes for the specified angles were between 5 % and 9%. The wide difference in the deviation may be due to the fact that the model does not capture the dynamic characteristics of the machine tool. More acceleration forces are required to actuate the feed drive at higher feedrates which result in feed axes power requirement increase. Additionally, the energy required by the feed axes to execute a linear toolpath during air cutting can be estimated using Equation 10. Consequently, the results of some of the predicted and measured energy demand of the feed axes during air cutting are presented in Table 7. Table 7 Predicted and Measured energy demand of the feed axes