High-Performance Control of Piezoelectric Tube Scanners

• Published in: IEEE transactions on control systems technology Vol. 15; no. 5; pp. 853 - 866
• Main Authors: Bhikkaji, B.., Ratnam, M.., Fleming, A.J., Moheimani, S.O.R.
• Format: Journal Article
• Language: English
• Published: New York IEEE 01.09.2007; The Institute of Electrical and Electronics Engineers, Inc. (IEEE)
• Subjects: Actuation; Amplifiers; Atomic force microscopy; Charge; Charge amplifiers; Control systems; damping; Feedback; feedback control; Hysteresis; piezoelectric tube; Piezoelectricity; Probes; raster pattern; Resonance; resonant mode; Robust control; Surface topography; system identification; Tubes; Tunneling; Vibration control; Voltage amplifiers
• ISSN: 1063-6536; 1558-0865
• DOI: 10.1109/TCST.2007.902947

In this paper, a piezoelectric tube of the type typically used in scanning tunneling microscopes (STMs) and atomic force microscopes (AFMs) is considered. Actuation of this piezoelectric tube is hampered by the presence of a lightly damped low-frequency resonant mode. The resonant mode is identified and damped using a positive velocity and position feedback (PVPF) controller, a control technique proposed in this paper. Input signals are then shaped such that the closed-loop system tracks a raster pattern. Normally, piezoelectric tubes are actuated using voltage amplifiers. Nonlinearity in the form of hysteresis is observed when actuating the piezoelectric tubes at high amplitudes using voltage amplifiers. It has been known for some time that hysteresis in piezoelectric actuators can be largely compensated by actuating them using charge amplifiers. In this paper, high-amplitude actuation of a piezoelectric tube is achieved using a charge amplifier.