| Abstract: |
Several approaches for the precision control of micro-scale positioning mechanisms, or MEMS nanopositioners, are presented along with initial experimental results which demonstrate nano-scale positioning resolution. The MEMS nanopositioners discussed in this paper are novel precision mechanisms comprised of a bent-beam thermal actuator and a flexure mechanism for each degree of freedom (DOF). These mechanisms can be used for a host of ultra-precision positioning applications, including nanomanipulation, scanning probe microscopy, high-density data storage and beam steering arrays. Concentrating on a 1 DOF MEMS nanopositioner, empirical static and dynamic models have been derived using characterization data obtained from experiments with optical and laser probe microscopes. Based on these models, three control approaches have been developed: 1) a quasi-static nonlinear open-loop controller, 2) a nonlinear forward compensator, and 3) a nonlinear PI controller. Simulation andinitial experimental results are presented, and the benefits of each of these approaches are discussed. |
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