Object-Oriented Modelling of Flexible Cables based on Absolute Nodal Coordinate Formulation

Cable-pulley system consists of several segments of cables, winches, and pulleys, which is used in a wide range of engineering applications such as lifting equipment and pulley systems, however its dynamics simulation has been a tough issue in the Modelica community. The absolute nodal coordinate formulation (ANCF) uses global displacements and slopes at nodes to describe the geometry of the deformed body, which allows the derivation of constant mass matrices and zero-valued quadratic velocity dependent centrifugal and Coriolis forces, demonstrating its powerful capacity to model flexible multi-body systems for nearly two decades. This paper presents an object-oriented approach to model cable-pulley system, where flexible cables are discretized using ANCF cable elements. It is compatible with the Modelica Multibody Library by using a unified Frame interface and enables coupled analysis of cables and rigid bodies. The paper provides a rich set of application examples showing the ease and efficiency of the Modelica-based component drag-and-drop modelling way for modelling cable-pulley system.