Experimental Research of ultrasonic motor Characteristics in micro EDM

On ultra precision cutting, grinding and non-traditional machining, there is a hard problem between long travel and high precision. A new multi-dimension, low speed, nanometer level precision minute electric spark forming system driven by ultrasonic motors was built. A study of the basic characteristics of the ultra-precision platform driven by the ultrasonic motor was conducted in this paper. The control method of digital PID combined with bidirectional static error compensation enables the platform to realize the submicron accuracy in a stroke of hundreds of millimeters, with the minimum speed of 0.1 mu m/s and the minimum closed loop step of 100nm. All the achievements would provide theoretic reference to the design of these kinds of ultra precision platform.