Feedforward control of a closed-loop piezoelectric translation stage for atomic force microscope
Rev. Sci. Instrum. 78, 013702 (2007); doi:10.1063/1.2403839
Published 11 January 2007
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Simple feedforward ideas are shown to lead to a nearly tenfold increase in the effective bandwidth of a closed-loop piezoelectric positioning stage used in scanning probe microscopy. If the desired control signal is known in advance, the feedforward filter can be acausal: the information about the future can be used to make the output of the stage have almost no phase lag with respect to the input. This keeps in register the images assembled from right and left scans. We discuss the design constraints imposed by the need for the feedforward filter to work robustly under a variety of circumstances. Because the feedforward needs only to modify the input signal, it can be added to any piezoelectric stage, whether closed or open loop.
©2007 American Institute of Physics
| History: | Received 4 October 2006; accepted 7 November 2006; published 11 January 2007 |
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http://link.aip.org/link/?RSINAK/78/013702/1 |
REFERENCES (34)
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