How car design has gone virtual

In the past, cars were built almost by a process of trial and error. You built a prototype, then tested it to find out what worked and what didn't. Nowadays, much of this work is done by computers.

Theo Leggett has been talking to Stephen Remondi, chief executive of Exa Corporation, to see how 3D simulations are being used by designers to refine their work in the virtual world before a single car panel has been built in the real one.