Cabriolets often have a lower torsional stiffness than cars with a closed body design. So-called x-braces are installed in the undercarriage for additional support. The use of CFRPs (carbon-fiber reinforced plastics) and optimization of component geometry have enabled reductions of the overall mass from around 70kg, in the preliminary draft made from metal, to less than 20kg. This has significantly contributed to compliance with the permissible emission limits of the vehicle.
The construction and engineering specifications of the front part of high-speed trains can present significant challenges. Keeping construction costs low is an important factor, yet at the very fore are issues such as the integration of metal elements (e.g. front hatch hinges and their operation), fire protection requirements, and recurring operational stress and strain factors.
The analysis phase considers the geometric non-linear effects, the contact conditions for bondings and lever bearings, and a fatigue analysis of the metal and fiber reinforced structure with cumulative damage from non-proportional load series.