
175Friction-Induced Instabilities and Vibrations
friction decreasing with increasing velocity. Each of these phenomena can be
observed in tribological systems.
6.5.3 A Slip Pulse
Nosonovsky and Adams (2001) also investigated the possible relative motion
of the two bodies due to the presence of a propagating stick–slip pulse.
Equation (6.194) gives the ratio of shear and normal stresses (i.e., M), whereas
Equation (6.197) gives the ratio of normalized shear stress to relative slip
velocity (i.e., α). Each of these quantities is independent of position, time,
wavelength, and wave amplitudes for given values of wave angles.
Nosonovsky and Adams ( ...