In this paper a nano-precision positioning system with 1mm travel length, which is composed by a voice coil motor (VCM), flexural stage, an inverted lever, and laser interferometer as positioning sensor, was established. The flexural stage was designed by using genetic algorithm. Because the output force of the VCM is too small, an inverted lever was used to enlarge the output force. A robust controller was designed by using N-times feed-forward control role together with PID control. Three different experiments were conducted: (1) fixed point test; (2) stepping test; and (3) ramp tracking test. From the experiment results, it was found that the bias was equal 0.013 nm with standard deviation (1σ) equals to 3.024 nm, for fixed-point control. While for stepping test, the bias was within 0.2 nm and 1σ value less than 4.5 nm with settling time within 0.17 to 0.71 second. For ramp tracking test, the bias was less than 0.02 nm and 1σ value less than 3.5 nm. Finally, it was found that the smallest step for this positioning system is 10 nm, and can travel 1 mm with bias equal to 0.251 nm, 1σ equals to 3.698 nm.
MODELING OF HIGH PRECISION POSITIONING SYSTEM / DIDELIO TIKSLUMO PADĖTIES NUSTATYMO SISTEMOS MODELIAVIMAS