Cranes on offshore vessels are subjected to crane dynamics, structural couplings to the vessel, and environmental influence by waves and currents. The recent trend has been to use larger cranes on smaller vessels, which makes the lifting operation more complex and potentially dangerous. The use of digital twins (DTs) is emerging as one way to enable safer operations, real‐time simulation, and maintenance prediction. On offshore vessels, a DT can monitor the lifting operation to create a safer work environment. The SPADE (stakeholders, problem formulation, alternatives, decision making, and evaluation) model has been used as a framework toward the creation of a DT of cranes on offshore vessels. Several cases involving simulation of cranes revealed the lack of an adequate simulation of cable and pulleys suitable for use in a DT. The simulation is important for accurate results and for implementation in control systems. A trade study was performed to determine a numerical method adequate for cable and pulley simulation. The trade study identified the absolute nodal coordinate formulation in the framework of arbitrary Lagrangian–Eulerian as a promising numerical formulation.

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Simple and computationally efficient drill string models running real-time describing motion in all axes in directional wells are important for the implementation of closed-loop control and assisted monitoring during drilling operations. This paper proposes a new simplified three-dimensional model based on a parametric curve and lumped-parameter modeling, where Kane’s method is used to establish the equations of motion. Validation of the steady-state motion and convergence for the lumped model in vertical and horizontal alignment was compared with a finite-element model. The configuration and restoring forces show good results compared with finite-element analysis. Hence, the model demonstrate the axial contraction as a function of the body restoring forces being oriented to the inertial frame, inherently producing nonlinear coupled axial tension forces. The qualitative response of the model is confirmed in simulation case studies, being showcased by a deviated J-well configuration. Traveling block velocity and top drive torque are included as actuated inputs to analyze off-bottom friction and contact along the wellbore. The model is proposed to act as a virtual sensor for drilling directional wells.