Up to now, self-protection was the main item car manufacturers focused on for passive safety. But the improvements have led to more aggressive vehicles in car to car impacts, and phenomena that happen in these crashes are not well understood.

However it seems that good interaction is a prerequisite, otherwise cars have to cope with loads they have not been designed for.

PSA’s proposal is to achieve car compatibility in two steps.

The first step consists in dealing with the most important problems:​

• Improve geometrical compatibility with a test in which the vehicle has to use the connections between its load paths in order to create a good interaction surface with the barrier.
• Improve compartment stiffness - we are sure it will reduce the risks of being crushed in case of incompatibility - by imposing a minimum compartment resistance.

Front-end stiffness and energy absorption could then be put under control in a second step when we have a better knowledge of compatibility, and depending on the improvements obtained with the first step.