Analysis and design of composite structures is complex because they are anisotropic and can involve many different constituent materials. Different processes and materials mean that ‘design for manufacturing’ is integral in developing a composite product. Various software packages provide early stage comparisons of composites with other materials, taking into account manufacturing processes and providing cost estimates.
Extensive databases of material properties exist and several composite design tools have been developed which are compatible with leading commercial 3D CAD systems. These now extend beyond structural / finite element analysis to integrate with manufacturing processes, surface engineering, and produce detailed drawings of how plies are cut and laid up, inserts are incorporated, etc.
‘Nesting’ software optimises the layout of pieces to be cut from a roll of fabric, while still respecting fibre alignment, which significantly reduces waste. Tools now exist to show the operative exactly where to lay up the plies using optical imaging combined with virtual reality or laser projection. In some cases, automatic ‘pick and place’ systems are used. Tracking software can give vital information for each constituent of a part and each step of the process.
There are now 3D printing processes which incorporate fibres, and hybrid parts can be made with a continuous fibre composite combined with 3D printed or injection moulded elements.
Skilled operatives are still very important, but automation is developing to improve consistency, quality and speed in manufacture.