Geometry modelling of warp knitted fabrics with 3D form

Warp knitted fabrics are widely used in medical and technical applications, as well as for clothing textiles. To predict their properties, it is useful to have knowledge about the yarn geometry and the yarn interactions within these fabrics. The geometrical modelling of warp knitted structures from single bed knitting machines is documented in the literature. This text concentrates on a computation of the geometry of warp knitted structures, which have complex 3D forms or which are draped over similar ones. The topological information about the structure produced on the machine, is used to create the basic geometry of this structure. After creating the basic geometry, it is transferred to a 3D deformed state of the relaxed fabric. The paper starts with a short overview of the research papers about simulation of warp knitted structures. General theoretical remarks about the transformation from basic structure to 3D structure are given. Examples of spacer fabric with constant or non-constant thickness and tubular fabrics are included. All the results concentrate on the topological representation of the geometry and at this stage do not take into account the influence of internal and external forces exerted on the fabric.