DEVELOPMENT AND CONTROL OF XY STAGE WITH A HYBRID BOLT CLAMPED LANGEVIN TYPE ULTRASONIC MOTOR

摘要

The development and control of XY stage driven by ultrasonic linear motor is presented. In this paper, the stage is driven by the hybrid-bolt clamped Langevin-type (Hybrid BLT) ultrasonic motor which consists of a longitudinal and a lateral PZT. The hybrid BLT is excited by its matched natural frequency without a discordance between natural frequency of a 3rd longitudinal mode and a 6th lateral mode. For fine and stable control performance, Nominal characteristics trajectory following (NCTF) control method is adopted. The NCTF control method does not require an exact mathematical model of the Hybrid BLT and is determined with open loop response based on simple experiment. Consequently, the experimental result shows that the BLT system achieved nanometric accuracy.