ALE has developed in-house software called PresVes which is able to simulate fiber circuits and fiber patterns according the netting theory and is written in Matlab. PresVes is able to export machine code for the tumble winder at ALE. Furthermore, the fiber network can be exported as an orphan mesh in order to perform FEA. The PresVes code has a version-control system and winding pattern designs receive a unique number for each run. Input and all relevant output of a design is stored in a single file and the unique design number is included in the name of the file. Hence, a design number is an internal clear definition of which winding pattern and machine settings to use.
The netting theory does not take resin into account and assumes that the fiber bundles are wound according geodetic paths on the tank. The bundles are equally tensioned everywhere, i.e. isotensoid. The shape of the liner is a result of the assumption that the bundles are equally tensioned. Geodetic paths are defined as paths with the shortest distance between points on the surface where the bundle will not be subjected to friction. Geodetic circuits do not automatically imply that a winding pattern is found. Therefore, PresVes allows for physical friction of the paths to be able to create realistic winding patterns.