Title
Lyapunov Estimator for High-Speed Demodulation in Dynamic Mode Atomic Force Microscopy.
Abstract
In dynamic mode atomic force microscopy (AFM), the imaging bandwidth is governed by the slowest component in the open-loop chain consisting of the vertical actuator, cantilever, and demodulator. While the common demodulation method is to use a lock-in amplifier (LIA), its performance is ultimately bounded by the bandwidth of the postmixing low-pass filters. This brief proposes an amplitude and phase estimation method based on a strictly positive real Lyapunov design approach. The estimator is designed to be of low complexity while allowing for high bandwidth. In addition, suitable gains for high performance are suggested such that no tuning is necessary. The Lyapunov estimator is experimentally implemented for amplitude demodulation and shown to surpass the LIA in terms of tracking bandwidth and noise performance. High-speed AFM images are presented to corroborate the results.
Year
DOI
Venue
2018
10.1109/TCST.2017.2692721
IEEE Trans. Contr. Sys. Techn.
Keywords
Field
DocType
Convergence,Demodulation,Bandwidth,Kalman filters,Transfer functions,Dynamics,Force
Lyapunov function,Demodulation,Control theory,Kalman filter,Control engineering,Bandwidth (signal processing),Transfer function,Mathematics,Amplifier,Actuator,Estimator
Journal
Volume
Issue
ISSN
26
2
1063-6536
Citations 
PageRank 
References 
0
0.34
0
Authors
5