Transient eigenmodes analysis of single-impact cantilever dynamics combining Fourier and wavelet transforms

Abstract

The transient eigenmode structure of an interacting cantilever during a single impact on different surfaces evidences the excitation of higher flexural modes and low frequency oscillations. The frequency shift of the fundamental mode after the tip comes into contact with the sample surface allows calculating the tip-sample interaction stiffness and evidences the role of capillary condensation and surface wettability on the cantilever dynamics. Wavelet transforms are used to trace the origin of spectral features in the cantilever spectra and calculate force gradients of the tip-sample interaction.

Analysis of Energy Density Spectrum of Lowvelocity Impact in Honeycomb Sandwich Panel with FBG

“…Energy analysis of IMPACT response signal monitored by FBG sensors is received by wavelet packet. Daubechies wavelet has the compact support set, the localization ability is strong, and the application precision is high, as shown in a paper [12]. In the experiment, the dbN wavelet is used to deal with the signal, and the decomposition scale is chosen as 5.…”

Data acquisition and imaging using wavelet transform: a new path for high speed transient force microscopy

“…45 Using the WT, not only can the steady state response of the cantilever be detected, but also the whole dynamicsincluding transient and higher frequency responsesare captured and recorded. Previously, the WT has been used in AFM for the analysis of scanned images, 46 eigenmodes and energy dissipation for force spectroscopy, 43,44,[47][48][49][50][51][52] characterization of passive microrheology of living myoblasts 53 and investigation of the amplitude of higher harmonics in tapping mode AFM. 41,42 In this paper, for the rst time, wavelet theory is used to analyze the multidimensional dynamics of both amplitude and phase of the cantilever signal acquired during imaging.…”

Theory of Single-Impact Atomic Force Spectroscopy in liquids with material contrast

“…The goal of the present theoretical analysis is to show that it is possible to go beyond Fourier analysis 16 – 18 and discriminate the viscoelastic properties of heterogeneous samples using the cantilever response to a single impact of the tip 19 on the sample’s surface in a liquid environment. Using a model that takes into account the lowest three flexural cantilever’s modes as well as the viscoelastic properties of the sample’s surface, we calculate the tip trajectory initiated by an impulsive excitation of the cantilever.…”