Suppressing nano-scale stick-slip motion by feedback

TL;DR

This paper introduces a force sensing feedback control method to suppress nano-scale stick-slip motion in atomic force microscopy, improving manipulation precision despite system uncertainties.

Contribution

A novel real-time force sensing feedback control approach is proposed to reduce stick-slip motion in nano manipulation, addressing limitations of existing virtual feedback techniques.

Findings

Enhanced precision in nano manipulation through feedback control.

Robustness of the method under parameter uncertainties.

Theoretical and simulation validation of the control strategy.

Abstract

When a micro cantilever with a nano-scale tip is manipulated on a substrate with atomic-scale roughness, the periodic lateral frictional force and stochastic fluctuations may induce stick-slip motion of the cantilever tip, which greatly decreases the precision of the nano manipulation. This unwanted motion cannot be reduced by open-loop control especially when there exist parameter uncertainties in the system model, and thus needs to introduce feedback control. However, real-time feedback cannot be realized by the existing virtual reality virtual feedback techniques based on the position sensing capacity of the atomic force microscopy (AFM). To solve this problem, we propose a new method to design real-time feedback control based on the force sensing approach to compensate for the disturbances and thus reduce the stick-slip motion of the cantilever tip. Theoretical analysis and numerical simulations show that the controlled motion of the cantilever tip tracks the desired trajectory with much higher precision. Further investigation shows that our proposal is robust under various parameter uncertainties. Our study opens up new perspectives of real-time nano manipulation.