Change search
ReferencesLink to record
Permanent link

Direct link
Model for contact between finger and sinusoidal plane to evaluate adhesion and deformation component of friction
KTH, School of Industrial Engineering and Management (ITM), Machine Design (Dept.).
KTH, School of Industrial Engineering and Management (ITM), Machine Design (Dept.).ORCID iD: 0000-0003-2489-0688
KTH, School of Industrial Engineering and Management (ITM), Machine Design (Dept.).
2016 (English)In: Tribology International, ISSN 0301-679X, E-ISSN 1879-2464, Vol. 96, 389-394 p.Article in journal (Refereed) PublishedText
Abstract [en]

One of the main parameters affecting finger friction, friction-induced vibrations in the finger, and consequently tactility is surface topography. Recently Skedung et al. performed finger friction measurements on fine controlled surfaces. These surfaces were sinusoidal with wavelengths from 0.27 to 8.8 mu m and amplitudes from 0.007 to 6 mu m. Building on those tests an analytical model for the contact was developed to explain the differences in friction coefficient. The contact was modelled as trapezoids in a circular pattern pressed against a sinusoidal plane. Results showed that the calculated contact area and therefore friction coefficient corresponded well with the measurements. This model can be used to see how the different surface parameters influence friction.

Place, publisher, year, edition, pages
Elsevier, 2016. Vol. 96, 389-394 p.
Keyword [en]
Finger, Friction, Contact area, Adhesion
National Category
Mechanical Engineering
URN: urn:nbn:se:kth:diva-184014DOI: 10.1016/j.triboint.2014.12.020ISI: 000371100800036ScopusID: 2-s2.0-84959542022OAI: diva2:915372

QC 20160330

Available from: 2016-03-30 Created: 2016-03-22 Last updated: 2016-05-09Bibliographically approved
In thesis
1. Adhesion and Friction - a Study on Tactility
Open this publication in new window or tab >>Adhesion and Friction - a Study on Tactility
2016 (English)Doctoral thesis, comprehensive summary (Other academic)
Abstract [en]

Although we are surrounded by hundreds of surfaces we can still distinguish them from each other simply by touch. The tactile information, interpreted by our brain and given by our fingers, is precise, but to put words to the sensation is very difficult — is it smooth, sticky or harsh? We do not only perceive surfaces differently, we also describe them in our own way. Luckily the forces and deformations that the skin are exposed to when sliding over a surface is ruled by laws of nature.

This thesis investigates the contact between finger and surface and how it is affected by, for example, material properties, surface texturing or changes in climate. By measuring contact area, friction coefficient, and adhesion, using different materials and under different conditions, conclusions could be drawn. Also, a model for the contact between a finger and a sinus­oidal surface was developed, which could be used to estimate contact area, deformation and resulting friction coefficient.

Results showed how differences in for example material, surface topography and environ­ment affect the interaction between finger and surface, and what consequences it has. If the objective is to change the feel of a surface or to alter the grip, this thesis could work as a support.

Paper A investigates the area and friction between finger and glass surface under different conditions.

Paper B presents a model for the contact area and deformation for a finger in contact with a sinusoidal surface.

Paper C is a validation of the contact area model. Here it was used on new surfaces and compared with new finger friction measurements.

Paper D mainly examines whether the adhesion or stickiness of different surfaces is distinguishable by a test panel and how this affects the perceived pleasantness of the surface.

Paper E relates to the adhesion and friction for a bioskin probe and skin. Tests were made to evaluate how an artificial probe can be used to evaluate the tactile properties of a surface.

Abstract [sv]

Även om vi omges av hundratals olika ytor kan vi fortfarande skilja dem åt med hjälp av känseln. Den taktila informationen från fingertopparna som tolkas av hjärnan är precis, men att sätta ord på hur ytan känns är väldigt svårt. Len, sträv eller grov? Vi upplever inte bara ytorna olika utan beskriver dem också på olika sätt. Krafterna och deformationerna som huden utsätts för när den glider över en yta styrs dock av naturlagar.

Denna avhandling utreder kontakten mellan fingertopp och yta och hur den påverkas av exempelvis materialval, ytstruktur eller förändringar i klimat. Genom mäta kontaktarea, friktionskoefficient och adhesion för olika material i varierande omgivning kunde slutsatser dras. En modell för kontakten mellan fingertopp och sinusformad yta togs fram vilken kunde användas till att uppskatta kontaktarea, deformation och resulterande friktionskoefficient.

Resultaten visade hur skillnader i exempelvis material, yttopografi och omgivning påverkar kontakten mellan finger och yta och vilka kon­sekvenser detta får. Om målet är att förändra känslan eller friktionen för en yta kan denna avhandling fungera som stöd.

Artikel A undersöker kontakten och friktionen mellan fingertopp och glasyta för olika förhållanden.

Artikel B presenterar en modell för arean och deformationen som sker för fingertopp och sinusformad yta i kontakt.

Artikel C är en validering av modellen. Här användes den för nya ytor och jämfördes med nya mätningar av fingerfriktion.

Artikel D undersöker i huvudsak huruvida en testpanel kan särskilja adhesionen för olika ytor och hur detta påverkar hur den känns.

Artikel E arbetar vidare med adhesion och undersöker och hur en testkropp av artificiell hud kan användas för adhesionsmätningar av en yta. Detta för att med relativt enkla mätningar kunna uppskatta ytans taktila egenskaper.

Place, publisher, year, edition, pages
Stockholm: KTH Royal Institute of Technology, 2016. xii, 42 p.
TRITA-MMK, ISSN 1400-1179 ; 2016:03
Adhesion, finger, friction, humidity, material, model, tactile friction, tactility
National Category
Mechanical Engineering
Research subject
Machine Design
urn:nbn:se:kth:diva-186208 (URN)978-91-7595-955-9 (ISBN)
Public defence
2016-05-27, F3, Lindstedtsvägen 26, KTH Campus, Stockholm, 14:00 (English)

QC 20160504

Available from: 2016-05-09 Created: 2016-05-04 Last updated: 2016-05-09Bibliographically approved

Open Access in DiVA

No full text

Other links

Publisher's full textScopus

Search in DiVA

By author/editor
Duvefelt, KennethOlofsson, UlfJohannesson, Carl Michael
By organisation
Machine Design (Dept.)
In the same journal
Tribology International
Mechanical Engineering

Search outside of DiVA

GoogleGoogle Scholar
The number of downloads is the sum of all downloads of full texts. It may include eg previous versions that are now no longer available

Altmetric score

Total: 16 hits
ReferencesLink to record
Permanent link

Direct link