Dynamic behavior of ultra precision feed axis at increased velocities

摘要

The processing speed of machine tools for ultra precision manufacturing are low compared to precision manufacturing to satisfy the precision requirements. To increase the productivity and develop machines for ultra precision high performance cutting (UP-HPC) it is essential to examine and compensate dynamic effects. In this work the positioning behavior of an ultra precision feed axis at different setpoint velocities is analyzed and compared to a high speed feed axis. It is observed that the ultra precision feed axis has a large overshoot of several micrometers if the velocities are increased. Further, the decay time of the ultra precision feed axis exceeds the decay time of the high speed feed axis by more than factor two. These two characteristics increase the production time, because of long tool paths and many reversal points, which are often required to keep the kinematic roughness low, especially in ultra precision raster milling.