Geometrical Modeling of the Yarn Paths in Three-dimensional Braided Structures

A circular braiding process is adapted to produce three-dimensional shapes by braiding over a contoured mandrel. The present work deals with the simulation of various braided structures. The simulated structures are based on geometrical models developed for yarns on different shapes of mandrels. The geometry of a braided structure depends upon the machine parameters, such as number of yarn carriers, rotational speed of the carriers, take-up speed, and the effective perimeter of the mandrel cross section. Virtual reality modeling language (VRML) has been employed as a visualization tool to simulate these geometrical models on a predefined mandrel geometry. Models relate to the machine speeds and a number of machine settings. The path of the yarn on the mandrel is dependent upon the shape of the mandrel, i.e., if it is circular then it will be in the form of a helix or if it is a cubical body then it will be in the form of straight lines. An expert system has been generated to take into account all the parameters interfacing with VRML to simulate the braid geometry. A comparison is also made between the experimental and simulated structures.