Inside a modern car, passengers are protected by ever increasing numbers of airbags, protecting everything from head to knees. For those pedestrians unlucky enough to be struck by a vehicle however, there isn’t much to cushion the blow between a fragile body and unyielding metal.

A team at Cranfield University in the UK has come up with an answer in the form of a U-shaped airbag which deploys from beneath the bonnet, designed to provide additional protection for pedestrians thrown onto the windscreen and front pillars of a moving car.

The design also pushes the rear of the bonnet upwards which increases space between the bonnet and engine to prevent intrusion from the engine below as the bonnet crumples.

Initial testing by the Cranfield University team shows the new system has the potential to reduce pedestrian injuries by half. While some car manufacturers have shown pedestrian airbag systems in the past, none have caught on. The Cranfield team however hopes to see its improved system adopted within the next five years.

Roger Hardy, who led the team, hopes that in time car makers will be legally obliged to offer pedestrian airbags. Until that happens across the fleet, Mr Hardy believes safety assessment groups such as Euro NCAP will give higher safety scores to cars fitted with the technology.