Creep, Hysteresis, and Vibration Compensation for Piezoactuators: Atomic Force Microscopy Application

TLDR

Loss of positioning precision in piezoactuators due to hysteresis, creep, and induced vibrations limits their use in high‑speed applications such as SPM‑based nanofabrication and ultra‑high‑precision optical systems. This study develops an integrated inversion‑based compensation scheme for creep, hysteresis, and vibrations to achieve ultra‑high‑precision piezoactuator positioning, illustrated with a scanning probe microscopy example. The approach employs an inversion‑based controller that simultaneously mitigates creep, hysteresis, and vibration effects, and is implemented on an atomic force microscope. Experimental results on the AFM demonstrate substantial improvements in positioning precision and operating speed.

Abstract

This article studies ultra-high-precision positioning with piezoactuators and illustrates the results with an example Scanning Probe Microscopy (SPM) application. Loss of positioning precision in piezoactuators occurs (1) due to hysteresis during long range applications, (2) due to creep effects when positioning is needed over extended periods of time, and (3) due to induced vibrations during high-speed positioning. This loss in precision restricts the use of piezoactuators in high-speed positioning applications like SPM-based nanofabrication, and ultra-high-precision optical systems. An integrated inversion-based approach is presented in this article to compensate for all three adverse affects—creep, hysteresis, and vibrations. The method is applied to an Atomic Force Microscope (AFM) and experimental results are presented that demonstrate substantial improvements in positioning precision and operating speed.