Brownian friction dynamics: fluctuations in sliding distance

TL;DR

This study investigates the fluctuations in the sliding position of blocks under constant force, combining experiments and simulations to understand the noise characteristics in frictional dynamics.

Contribution

It introduces a spring-block model with viscoelastic springs to simulate asperity interactions, aligning well with experimental fluctuation data.

Findings

Displacement power spectra match experimental results

Fluctuations are effectively modeled by the spring-block system

The model captures key features of frictional noise

Abstract

We have studied the fluctuation (noise) in the position of sliding blocks under constant driving forces on different substrate surfaces. The experimental data are complemented by simulations using a simple spring-block model where the asperity contact regions are modeled by miniblocks connected to the big block by viscoelastic springs. The miniblocks experience forces that fluctuate randomly with the lateral position, simulating the interaction between asperities on the block and the substrate. The theoretical model provides displacement power spectra that agree well with the experimental results.