Nonlinear Control Techniques for the Atomic Force Microscope System

2002 ◽  
Author(s):  
Yongchung Fang ◽  
Matthew G. Feemster ◽  
Darren M. Dawson ◽  
Nader Jalili
Keyword(s):  
Nonlinear Control ◽  
Atomic Force Microscope ◽  
Control Algorithm ◽  
Interaction Force ◽  
Nonlinear Observer ◽  
Nonlinear Controller ◽  
Control Approach ◽  
Control Techniques ◽  
Atomic Force ◽  
Periodic Dynamics

In this paper, three nonlinear control techniques are proposed for an atomic force microscope system. Initially, a learning-based control algorithm is developed for the microcantilever–sample system that achieves asymptotic cantilever tip tracking for periodic trajectories. Specifically, the hybrid control approach utilizes a combination of a learning-based feedforward term to compensate for periodic dynamics while hign-gain terms are utilized to account for non-periodic dynamics. An adaptive control algorithm is then developed to achieve asymptotic cantilever tip tracking for bounded tip trajectories despite uncertainty throughout the system parameters. Lastly, a nonlinear controller coupled with a nonlinear observer is designed to provide for asymptotic tracking and interaction force identification unders a set of assumptions.

Adaptive Multi-Loop Mode Atomic Force Microscope Imaging

2014 ◽  
Author(s):  
Juan Ren ◽  
Qingze Zou ◽  
Bo Li ◽  
Zhiqun Lin
Keyword(s):  
Image Quality ◽  
Atomic Force Microscope ◽  
Interaction Force ◽  
Control Techniques ◽  
Large Size ◽  
Atomic Force ◽  
Microscope Imaging ◽  
Major Bottleneck ◽  
Mode Tm ◽  
Superior Image Quality

An adaptive multi-loop mode (AMLM) imaging of atomic force microscope (AFM) is proposed. Due to its superior image quality and less sample disturbances, tapping mode (TM) imaging is currently the de facto most widely used imaging technique. However, the speed of TM-imaging is substantially limited, and becoming the major bottleneck of this technique. The proposed AMLM-imaging overcomes the limits of TM-imaging by utilizing control techniques to substantially increase the speed of TM-imaging while preserving the advantages of TM-imaging. The AMLM-imaging is tested and demonstrated through imaging a PtBA sample in experiments, and the experiment results demonstrated that the image quality over large-size imaging (50 μm by 25 μm) achieved at the scan rate of 25 Hz is at the same level of that when using TM-imaging at 1 Hz, while the probe-sample interaction force is smaller than that of the TM-imaging at 2.5 Hz.

Nonlinear control techniques for an atomic force microscope system

2005 ◽  
Vol 3 (1) ◽  
pp. 85-92 ◽  
Author(s):  
Yongchun Fang ◽  
Matthew Feemster ◽  
Darren Dawson ◽  
Nader M. Jalili
Keyword(s):  
Nonlinear Control ◽  
Atomic Force Microscope ◽  
Control Techniques ◽  
Atomic Force

A Finite-Impulse-Response-Based Approach to Control Acoustic-Caused Probe-Vibration in Atomic Force Microscope Imaging

2017 ◽  
Author(s):  
Sicheng Yi ◽  
Qingze Zou
Keyword(s):  
Atomic Force Microscope ◽  
Impulse Response ◽  
Controller Design ◽  
Finite Impulse Response ◽  
Feedforward Control ◽  
Acoustic Noise ◽  
Noise Cancellation ◽  
Control Approach ◽  
Atomic Force ◽  
Afm Imaging

In this paper, we propose a finite-impulse-response (FIR)-based feedforward control approach to mitigate the acoustic-caused probe vibration during atomic force microscope (AFM) imaging. Compensation for the extraneous probe vibration is needed to avoid the adverse effects of environmental disturbances such as acoustic noise on AFM imaging, nanomechanical characterization, and nanomanipulation. Particularly, residual noise still exists even though conventional passive noise cancellation apparatus has been employed. The proposed technique exploits a data-driven approach to capture both the noise propagation dynamics and the noise cancellation dynamics in the controller design, and is illustrated through the experimental implementation in AFM imaging application.

scholarly journals Оптимизация измерений вектора силы взаимодействия в атомно-силовой микроскопии

2021 ◽  
Vol 91 (6) ◽  
pp. 1043
Author(s):  
А.В. Анкудинов ◽  
А.М. Минарский
Keyword(s):  
Atomic Force Microscope ◽  
Satisfactory Agreement ◽  
Torsion Angle ◽  
Displacement Vector ◽  
Interaction Force ◽  
Optical Beam ◽  
Beam Deflection ◽  
Optimal Point ◽  
Atomic Force ◽  
The Ideal

The issue of optimization of measurements of three spatial components of the probe-sample interaction force and the corresponding displacement vector of the "ideal cantilever" is considered. To determine these components in an atomic force microscope with an optical beam deflection scheme, it is necessary to register the bending angles at least at two points on the rectangular cantilever and the torsion angle at any of them. It has been proven analytically that one optimal point is the intersection of the probe axis with the console plane. A method to calculate the position of another optimal point has been developed. An experiment was carried out to map the force and displacement vector, and satisfactory agreement with the theory was obtained.

Virtual Manipulation of Multi-Wall Carbon Nanotubes with Atomic Force Microscope

2012 ◽  
Vol 263-266 ◽  
pp. 468-471
Author(s):  
Zhan Gao ◽  
Shu You Zhang ◽  
Jie Hua Wang
Keyword(s):  
Carbon Nanotubes ◽  
Atomic Force Microscope ◽  
Interaction Force ◽  
Multi Wall Carbon Nanotubes ◽  
Force Modeling ◽  
Atomic Force ◽  
Current State ◽  
Deformation Simulation ◽  
Set Up ◽  
Vr Simulator

This paper describes a virtual reality (VR) simulator for the manipulation of carbon multi-wall nanotubes with atomic force microscope (AFM). Major challenges in interfacing a human operator with tasks of manipulating nanotubes via a haptic VR interface are outlined. After a review of our previous efforts, we present the current state of our VR simulator for multi-wall nanotube manipulation. The collision detection, interaction force modeling, deformation simulation and haptic rendering of nanotubes are then discussed. Results of virtual manipulation of carbon nanotubes are presented within an immersive VR set-up.

Measuring intermolecular binding forces with the Atomic-Force Microscope: The magnetic jump method

1994 ◽  
Vol 52 ◽  
pp. 1054-1055
Author(s):  
J. H. Hoh ◽  
P. E. Hillner ◽  
P. K. Hansma
Keyword(s):  
Bond Strength ◽  
Atomic Force Microscope ◽  
Interaction Force ◽  
Intermolecular Forces ◽  
Atomic Force ◽  
Novel Approach ◽  
Binding Forces ◽  
Afm Cantilever ◽  
Paramagnetic Beads ◽  
Direct Readout

The atomic-force microscope (AFM) can measure forces between atoms and molecules with a sensitivity of <10−12 N. By coating the AFM tip with specific molecules the types of interactions that can be examined will be greatly extended. Recently tips with biotin attached have been used to probe surfaces coated with avidin or streptavidin, to measure the respective bond strength.We have developed a novel approach to measuring intermolecular forces with the AFM that employs paramagnetic beads coated with one of the molecules to be studied. Beads are incubated with a surface coated with the second molecule, and allowed to form a specific bond. A small magnet glued to an AFM cantilever is then advanced toward the bead until the bond with between the two molecules breaks and the bead “jumps” to the magnet. The deflection of the cantilever provides a direct readout of the interaction force at the “jump,” and thereby a measure of the bond strength.

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