Surface roughness is an important factor influencing subsea cable/umbilical–soil interaction. The cable/umbilical goes through several steps before being laid on the seabed, including production, spooling, unspooling, and installation on the seabed. Yet, there is no standard method for assessing the outer sheath roughness, whether extruded or roving, of subsea cables/umbilicals, and outer sheath roughness has not been measured...