Rolling friction has been explained in terms of crack propagation through an adhesive joint. The contact between a smooth cylinder and flat has been regarded as an adhesive junction bounded by two cracks moving in the same direction at the same speed, one crack continually opening and one closing. Propagation of these cracks requires a force which is calculated from crack theory and shown to be...

We report on an experimental study of heterogeneous slip instabilities generated during stick-slip motions at a contact interface between a smooth rubber substrate and a patterned glass lens. Using a sol-gel process, the glass lens is patterned with a lattice of parallel ridges (wavelength, 1.6 μm, amplitude 0.35 μm). Friction experiments using this patterned surface result in the systematic oc...

Recently, several three-axial MEMS-based force sensors have been developed. This kind of force micro sensor is also called tactile sensor in literature for its similarities in size and sensitivity with human mechanoreceptors. Therefore, we believe these three-axial force sensors being able to analyse textures properties while sliding on a surface, as would do a person with his finger. In this p...

This paper reports on the use of Zr-based (Zr53Cu33Al9Ta5) thin film metallic glass (TFMG) for the coating of syringe needles and compares the results with those obtained using titanium nitride and pure titanium coatings. TFMG coatings were shown to reduce insertion forces by ∼66% and retraction forces by ∼72%, when tested using polyurethane rubber block. The benefits of TFMG-coated needles wer...

A method for controlling the grasping force when an object is grasped by artificial elastic fingers is proposed. First, the relationship between the stick area and the internal strain distribution of the finger is calculated using FE (finite element) analysis. Based on this relationship, a method is proposed for controlling the grasping force by decreasing the increasing ratio of the tangential...

This paper reports on spatially resolved measurements of the shear stress distribution at a frictional interface between a flat rubber substrate and a glass lens. Silicone rubber specimens marked close to their surface by a colored pattern have been prepared in order to measure the surface displacement field induced by the steady-state friction of the spherical probe. The deconvolution of this ...

In this paper, we present the development of a tire rubber deformation sensing system that provides the critical information for understanding and estimation of wheel/ground interactions for mobile robots and vehicles. Polyvinylidene fluoride (PVDF)based sensors are designed and fabricated to embed on the inner tread surface to measure the tire rubber tread deformation. Analytical models of the...

Friction coefficients are measured in ultrahigh vacuum using a tungsten carbide tribopin against thin films of sodium chloride and potassium iodide deposited onto clean iron. It is found, in accordance with previous measurements for potassium chloride on iron, that the friction coefficient falls from an initial value of 2 for the clean iron surface to a minimum value after a few tens of Ångstro...

BACKGROUND AND OBJECTIVES Studies have demonstrated that some cutaneous biophysical properties vary with age, gender and body sites. However, the characteristics of the skin friction coefficient in different genders and age groups have not yet been well established. In the present study, we assess the skin friction coefficient in a larger Chinese population. METHODS A total of 633 subjects (3...