抄録
Increased accuracy and higher repeatability for precision positioning systems have recently been the main requests in areas such as ultra-precision machine tools and semiconductor technologies. In order to minimize the non-linear stick-slip effect in the system, an air lubricated slide with friction drive has been developed and the micro-dynamic characteristic of the stage was evaluated under different aerostatic slide pressure and preload. A PID controller was used in the closed loop control system and an optic scale with 1nm resolution was used for precision position measuring. The micro-dynamic characteristics of the stage were evaluated under different aerostatic pressures and preloads of the friction drive. The results showed that the rms value of the measurement noise was about 10nm. With the PID controller inactivated, it was found that the rms value of the error motion reduced significantly when the preload of air lubricated friction drive got activated (from around 130nm dropped to under 20nm in the case of 0.2Mpa air slide pressure). Frequency spectrum analysis indicates that the noise is higher at 5Hz and 35Hz and can be reduced by increasing the pressure of air-slide.
