The role of the sliding direction against a grooved channel texture on tool steel: An experimental study on tactile friction

Abstract

a b s t r a c tTo control tactile friction, that is the friction between fingertip and counter-body, the role of surface texture is required to be unveiled and defined. In this research, an experimental approach is used based on measuring tactile friction for directional texture (grooved channel) with varying depths. For a reference surface, in this current case a polished surface from the same tool steel is compared. The experimental results are analyzed to explain the observed skin friction behavior as a function of surface texture parameters, sliding direction and applied normal load. Sliding parallel to the groove length shows greater values in COF than sliding perpendicular to the groove direction. Furthermore, parallel sliding reveals a higher dependency of COF on the depth of the grooved channel texture than perpendicular sliding. Application of the two term friction model suggests that the adhesion component of friction has greater impact on parallel than perpendicular sliding direction. According to the observations, grooved channels are well suited to control skin friction in direction dependent sliding, for moderately loaded contact situations. This experimental research contributes to the haptic perception related research, and to the development of other direction-dependent surface structures for touch.

Finger pad friction and tactile perception of laser treated, stamped and cold rolled micro-structured stainless steel sheet surfaces

“…The same sliding direction was performed in the friction measurements. According to the previous study, the sliding direction to the texture can alter the kinetic tactile friction between the fingertip and the counter-surface [23]. During the perception tests, the subject had unlimited time to explore the sample before reporting a judgment.…”

“…This apparatus, described in full detail in Ref. [23], is able to measure the outputting forces and torques from all three Cartesian coordination (x, y, and z) with the resolution of 25 mN in normal direction and 12.5 mN in tangential direction. Double sided tape was used to firmly fix the testing samples to the top of the force transducer.…”

Texture Design for Reducing Tactile Friction Independent of Sliding Orientation on Stainless Steel Sheet

“…This particular phenomenon is caused by the contribution of deformation component of friction in form of hysteresis [33,34]. Based on the previous study of sliding direction against a grooved channel on tool steel [39], the normal force (F N ) applied on the leading edge can be determined as follows:…”

“…The real contact area plays a pivotal role in skin friction. According to the research, skin friction decreases with the reduction in the real contact area [24,39]. In skin tribology, both the adhesion and deformation components of friction (two-term model of friction) contribute to tactile friction [8,9].…”

“…Surface textures are widely applied in studies on dynamic friction to reduce the adhesive component of friction, and most of them were carried out under unidirectional sliding conditions [5,17]. However, from our previous work [39], the orientation effect has great influence on the skin friction between fingertip and textured counter-surface [39]. An experimental approach was used based on measuring tactile friction on textured stainless steel sample with grooved channel.…”