Integration of a Flexible Pipes Simulation Tool in a CAD System

3D CAD systems are powerful tools in modelling solids or surfaces representing rigid bodies. For a comprehensive virtual prototype of devices and machines also flexible parts like cables, pipes and wires must taken into account. In this paper, we present a software system developed for simulating one-dimensional flexible parts, especially metallic-reinforced elastomers hoses, used for hydraulic power transmissions. For this purpose a finite element approach has been followed to find hose configurations for given boundary conditions determined by assembly positions. The model considers large displacements, as well as gravity and inner pressure effects. The tool has been implemented to interact as a knowledge-based system with a parametric 3D CAD modeller in order to allow real time definition of the design solution. Pipe fittings are selected and interactively assembled, the hose is chosen out of working parameters with the optimum length, and the simulation engine calculates the configuration and its deformation level. The system has been tested on mining equipment, which widely employs hydraulic transmissions for moving groups of components.