A MULTI-AXIS MOTION CONTROL SOLUTION OF LINEAR ULTRASONIC MOTORS FOR MICRO CNC MACHINE TOOLS - POWERED BY INDUSTRIAL ETHERNET TECHNOLOGY (ETHERCAT)

摘要

Linear ultrasonic motors have great advantages in high accuracy, self-locking, anti-EMI, etc., thus are suitable to be used as a motion stage in a micro machine tool. However, there are currently very seldom reports on using linear ultrasonic motors for a machine tool application. One of the most important reasons why the multi-axis ultrasonic motor stage is hard to be used in a high-precision machine tool is that the control technology for ultrasonic motors is not mature e-nough for NC tasks. The high precision feed motion implies high contour accuracy (rather than point-to-point accuracy), superfine interpolation, large look-ahead buffer, hard real-time ability, axes group control, high synchronization, etc. Unfortunately, the recent motion control vendors for ultrasonic motors have few considerations on C-NC applications.