Torsional stiction of an adhesive contact between a surface marked silicone rubber and a glass lens. The progressive propagation of slip from the periphery of the contact is detected from the distortion of the markers lattice.
Slip pulse propagation during stick-slip motion between a smooth silicone substrate and a glass lens patterned with an array of micrometric ridges. Color scale indicate the magnitude of the local sliding velocity at the contact interface. White circle delimits the contact area. The silicone substrate is moved from bottom to top with respect to the fixed glass lens.