Texture-Induced Modulations of Friction Force: The Fingerprint Effect
E. Wandersman
,
R. Candelier
,
G. Debregeas
,
A. Prevost
Physical Review Letters,
107, 16
Published 11 Oct. 2011
DOI: 10.1103/PhysRevLett.107.164301
ISSN: 0031-9007
Abstract
Modulations of the friction force in dry solid friction are usually attributed to macroscopic stick-slip instabilities. Here we show that a distinct, quasistatic mechanism can also lead to nearly periodic force oscillations during sliding contact between an elastomer patterned with parallel grooves, and abraded glass slides. The dominant oscillation frequency is set by the ratio between the sliding velocity and the grooves period. A model is derived which quantitatively captures the dependence of the force modulations amplitude with the normal load, the grooves period, and the slides roughness characteristics. The model's main ingredient is the nonlinearity of the friction law. Since such nonlinearity is ubiquitous for soft solids, this ``fingerprint effect{''} should be relevant to a large class of frictional configurations and have important consequences in human digital touch.
This publication is related to:
Mechanics of integrated and artificial biological systems