Back to overview

ACOF - Active Control of Friction

English title ACOF - Active Control of Friction
Applicant Meyer Ernst
Number 120202
Funding scheme Project funding (special)
Research institution Departement Physik Universität Basel
Institution of higher education University of Basel - BS
Main discipline Material Sciences
Start/End 01.04.2008 - 30.09.2011
Approved amount 347'326.00
Show all

Keywords (11)

control of friction; actuation of nano-contacts; structuring of surfaces; chemical and physical control of friction; lubrication; Fundamentals of Friction; nanopatterns; surface modifications; Actuation of contacts; collective phenomena of multi-contact systesm; time dependences of friction

Lay Summary (English)

Lay summary
We propose a joint experimental, theoretical and computational project aimed at designing methods and algorithms to control friction by both mechanical means and surface modification. To accomplish these goals, it is essential to understand the internal dynamics, i.e. the internal rates of structural rearrangement of confined systems under shear. In the proposed project we will utilize new advances in experimental and theoretical techniques to both acquire a detailed understanding of these processes and manipulate them. The interrelation between friction at the nano, micro and macroscopic scales will be explored.

Specific aims and objectives of this CPR are as follows:
•Understanding and modeling of the detailed dynamics of the short-time detachment process in multi-contact systems. What collective phenomena exist (e.g. coherent crack-like fronts of interface detachment) which do not play a role in the (local) dynamics of single contacts? Do the contact dynamics at microscopic scales inherently differ from single contact dynamics?
•Experimental characterization of changes in contact area and frictional resistance induced by normal and lateral vibration in nano-contacts, nano-contact arrays, and large spatially extended systems.
•Modeling feedback and direct methods of controlling frictional forces through the application of external oscillatory perturbations in the stick-slip and sliding regimes of motion. Optimization of the process of control friction in order to obtain large gains in reducing the applied force and to reduce significantly the transient time needed to reach the desired behavior.
•Development of efficient, wide-area fabrication of nano-patterned surfaces, and the use of nano-patterned mating surfaces to improve tribological performances of hi-tech mechanical devices at the nano and microscales in dry friction. This will include investigations of the effects of spatial non-uniformities on the collective dynamics along the interface.
•Experimental study of the flow behavior around lubricated contacts on micro- and nano- patterned geometries. This includes both the development of optimized nano- and micro- patterns and the study of the flow behavior on these surfaces in order to obtain very low friction nano-patterned surfaces working under realistic lubricating conditions.
•Development of a multiscale approach, which combines Molecular Dynamics simulations with larger scale ‘continuum-like’ descriptions, to model dry and lubricated friction at patterned surfaces. Derivation of constitutive relations for friction at patterned surfaces, and development of mean-field type description for simulations of friction processes at time scales and length scales relevant to tribological measurements.
Direct link to Lay Summary Last update: 21.02.2013

Responsible applicant and co-applicants


Associated projects

Number Title Start Funding scheme
137682 AFRI - Atomic Scale Friction and ACOF -Active Control of Friction 01.10.2011 Project funding (Div. I-III)