  A huge number of technological and biological systems involves the lubricated
contact between rough surfaces of soft solids in relative accelerated motion.
Examples include dynamical rubber seals and the human joints. In this study we
consider an elastic cylinder with random surface roughness in accelerated
sliding motion on a rigid, perfectly flat (no roughness) substrate in a fluid.
We calculate the surface deformations, interface separation and the
contributions to the friction force and the normal force from the area of real
contact and from the fluid. The driving velocity profile as a function of time
is assumed to be either a sine-function, or a linear multi-ramp function. We
show how the squeeze-in and squeeze-out processes, occurring in accelerated
sliding, quantitatively affect the Stribeck curve with respect to the steady
sliding. Finally, the theory results are compared to experimental data.
