How high-tech is body armour?
Conventional body armour is a foam which absorbs energy as it deforms, just like a sofa does when you flop onto it. Some manufacturers – for example Dainese with their armadillo-style back protector – add a hard outer shell to resist penetration by sharp objects and spread the load.
Others, such as Forcefield, use dense, energy-absorbing foam on its own, in case a hard shell creates an abrasion point which could hole the leathers as you slide down the road. Both systems have their merits.
But there is another way. It was invented in Brighton by a guy called Richard Palmer, and it’s called D3O. It isn’t a foam, but a mouldable polymer putty somewhere between a liquid and a solid. Pick it up and it resonates, a bit like when you bang the end of a plastic pipe with the flat of your hand. Push it slowly with your finger and it deforms easily. But whack it and it goes stiff.
The molecules inside the D3O lock together on impact. As soon as the impact fades, they slip past each other as before. The cornflour in custard does the same thing, which is why TV presenter John Tickle could once walk across a swimming pool filled with the stuff, then sank when he stood still.
In body armour D3O is stabilised by a carrier polymer, but it retains its other-worldly shock absorption properties. Tests on an impact rig to the CE standard show that a D3O knee protector transmits less force than very well-known rivals, despite being thinner.