In the PSE Petroleum Structural Engineering® software
, vessel dynamic motions are defined according to API 4F Specification for Drilling and Well Servicing Structures. The inertial forces due to the vessel dynamic motion as well as radial, tangential and translational forces due to the acceleration of masses attached to the drilling structures have a significant influence on design and reliability. In various production wells, the offshore drilling structures are located on top decks of vessels, semisubmersible or floating hulls. Vessel motion includes roll, pitch and yaw rotations and heave, sway and surge translations.