Prototypes

There's a misconception that invention is about having a great idea, tinkering with it in the garden shed for a few days, then appearing with the finished design. In fact, it's a far longer and iterative process - trying something over and over, changing one small variable at a time.  Trial and error. 

Dyson engineers make a lot of prototypes - quickly getting a feel for things and uncovering subtle design flaws you don't get from a computer screen.  They start as models made from card and foam.  Later they use SLS (Selected Laser Sintering) - a rapid prototyping technique that moulds plastic or ceramic particles together to form a fully-working model.