The latest safety device from Mercedes Benz is an underfloor airbag deployed by a new development of the PRE-SAFE system.
Braking bag prevents submarining
Showcased on a new Experimental Safety Vehicle (named ESF2009), the so-called ‘braking bag’ isn’t intended to soak up collision impacts, but when it inflates it drives a metal panel hard against the tarmac under the front of the car. The extra friction generated helps to slow the car fractionally and, more significantly, raises the nose of the car by 8cm. This extra lift could help to prevent your vehicle submarining under the obstacle you’ve driven it into – whether that be another car or the side of a lorry.
Another safety innovation that could one day appear on production models are Merc’s PRE-SAFE structural elements. These are concealed metallic structures that wait in a collapsed space-saving state until your car determines you are approaching an accident. At that point explosive charges similar to airbag actuators release gas into the structures – which Mercedes compare to inflatable mattresses – to unfold the metal sections and provide greater structural stability.
Inflatable metal airbags? Whatever next!
The benefits include packaging and weight, as greater strength and protection can be included in the increasingly tight installation spaces of modern cars, says Mercedes.
One of the major unresolved problems of these folded metal ‘airbags’ is that, once they’ve been fired, your car will be rather more deformed than it might otherwise have been the case – and unlike regular airbags they can’t be simply replaced.
‘These crash-responsive metal structures are therefore still a thing of the future – but the same was also once true of standard safety features like the airbag, ABS or ESP’, the company says.
The new ESF2009 concept car is being officially revealed at a safety conference in Stuttgart this week.
 The braking bag in action |
 Expanding metal structures |
 The ESF2009 concept car |
 Many features could make production |
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