Textile structures and properties are notable for being expressed in a great many inter-related ways. For example, a few independent parameters define a weave structure but many others are related to them ¨C and may themselves be chosen as the defining quantities. Weavers and fabric designers know about the relations between fabric weight, ends and picks per meter (or per inch), thread spacings, modular lengths, crimp, cover factors, yarn linear densities (tex or denier), yarn diameters, fibre density, yarn packing factors, etc, etc. The list is long, but the weave geometry of a simple fabric with a given pattern is basically defined by just five quantities (e.g. two yarn diameters, two thread spacings, and one crimp value). Of course, more inputs are needed for more complicated fabrics. Then we can add in costs (in ¡ê sterling, euros, dollars, etc) or strengths (with absolute units such as Newtons, kilograms force, and lbs-wt etc or normalised units, such as N/m, Pascals, psi, N/tex, g/den etc).
Conversion tool, known technically as TP Solver, provides the facility to convert between the different parameters. Any choice of a set of independent values will show all the related values at the click of a mouse, with automatic conversion between different units. The facility can be used independently when the user wants to carry out calculations, but is brought into other parts of TexEng programs to give freedom of choice for input parameters.
There are currently three available TP Solver models for fibres, yarns and woven fabrics. Provision will be included to link these conversion tools, for import/export between them and for linking conversion tools to databases, so that inserting, for example, a fibre name will automatically insert values from the database.