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A significant difficulty associated with achieving high scan speeds in scanning probe microscopes is that the probe is required to scan the sample in a zig-zag (raster) pattern. The fast axis of the scanner is required to track a non-smooth signal that contains frequency components beyond its mechanical bandwidth. Therefore, fast raster scans lead to(More)
—In this paper, we design feedback controllers for lateral and transversal axes of an atomic force microscope (AFM) piezoelectric tube scanner. The controllers are constrained to keep the standard deviation of the measurement noise fed back to the displacement output around 0.13 nm. It is shown that the incorporation of appropriate inner loops provides(More)
Tracking of triangular or sawtooth waveforms is a major difficulty for achieving high-speed operation in many scanning applications such as scanning probe microscopy. Such non-smooth waveforms contain high order harmonics of the scan frequency that can excite mechanical resonant modes of the positioning system, limiting the scan range and bandwidth. Hence,(More)
— We demonstrate the application of internal model control for accurate tracking of spiral scan trajectories, where the reference signals are orthogonal sinusoids whose amplitudes linearly vary with time. The plant is a 2-D microelectromechan-ical system nanopositioner equipped with in situ differential electrothermal sensors and electrostatic actuators.(More)
— In this brief, the transient performance of the signal transformation approach (STA) is considerably enhanced by initializing the state vector of the compensator to appropriate values. For triangular reference tracking, it is shown that the proposed method is identical to the impulsive state multiplication (ISM) approach. Through simulations and(More)