Fill a swimming pool with custard and you could feasibly run across without sinking in. Wet sand has similar properties. They're known as dilatant materials.
Running across custard swimming pools sounds like a fun way to demonstrate a physical process, but it can also have practical applications. Indeed, it can also save lives, and d3o, developed by British chemical lab d3o Lab, is designed to do just that. Equally as importantly, it could be used to save lives in serious car accidents too.
d3o gel, a putty-like substance, has the ability to harden almost instantly when subjected to a strong shear force, such as the impact of a speeding bullet. This has led to the material being considered as a lightweight and flexible alternative to materials such as kevlar in armored vests. It's also already in use in items such as ski jackets, cell phone protectors and motorcycle gloves, all of which are subject to impact shocks.
Mazda is one of the automakers now interested in exploring the possible benefits of using d3o gel in cars. Mazda's European R&D chief, Peter Birtwhistle, told Carsguide that innovations such as d3o were "fascinating" and presented "glimpses of future design".
"It has unlimited applications in a car to protect its occupants", reasons Birtwhistle. The technology could be used in a vehicle's seats and baby seats, or as a flexible cargo barrier that then offers protection in an accident.
We look forward to seeing whether the technology begins to filter into vehicles in the near future. In the meantime though, we advise against filling your car with custard...