Cars could soon be even safer in a side-on crashes, if a new system designed by German research engineers comes into use.
The system, called the Advanced Protection System (APROSYS), has been developed using a 17 million grant from the European Union.
It automatically boosts the side-protection strength of cars that are about to be hit by other vehicles.
Cameras monitor 20 metres around the car, and can identify a side-collision risk 200 milliseconds before impact.
The on-board computer then triggers a spring, pushing steel bolts fixed within the occupants' seats towards the car doors, where metal boxes also automatically fall into place.
'The system of the bolt and the metal box stabilises the car door and absorbs energy in a collision,' said project manager Bjorn Seipel of the Fraunhofer Institute for Structural Durability and System Reliability.
A European Commissioner added: 'This system will soon find its way to showrooms.'