Fast Tool Servo System for On-line Compensation of Error Motion on an Ultra-precision Lathe

摘要

In order to obtain high accuracy and a fine surface finish of large area workpiece, position control of machine tool has become the main concern to achieve high precision position control. In this system, diamond turning with a fast tool servo (FTS) driven by a piezoelectric actuator along with a capacitive displacement sensor was chosen as the fabrication method. A laser interferometer is implemented to measure the straightness error of the translational slide accurately. The detected error signals are compensated by the FTS during the cutting process. To achieve better tracking performance, proportional integral (PI) feed back control with a feed-forward predictor is implemented. Experimental results show that the FTS can effectively and successfully compensate the straightness errors of the X-axis translational slide of the miniature ultra-precision lathe.