The target of front crash protocols is to finally represent a « Car to Car » (C2C) impact, which is the most frequent configuration in real life. But C2C is a too complex and costly configuration to be applied on experimental and even numerical point of view.

Particularly, a numerical C2C simulation will require many finite elements (F.E.) and so heavy calculation time (with in addition, more numerical bug risks, because modeling the front interface between the 2 cars is complex ) ;​ and also, the Post calculation analysis is much more heavy ( 2 different cars to be analyzed + twice as biomecanic criteria if dummies models are implemented).

Furthermore, some specific criteria (specially compatibility criteria) can’t be rated during a C2C crash test, because they need a deformable barrier (which represents a medium car of the market) to be measured :​ as car front face aggressiveness characteristics, and global car’s stiffness (dynamometric force measurement on barrier trolley).

The goal of this study is to define the front crash protocol which responds the best at the following problem:​

• to represent the physics of C2C front crashes
• to be easier to use in car design process

For that purpose, we will follow the method below :​

FIRST, we will carry out a theoretical study of the C2C front crash, in order to understand its physical main phenomenon, under 3 different and complementary aspects:​

• Mathematical aspect with simple models,
• Numerical aspect with F.E. calculations,
• Experimental aspect with C2C tests analysis.

SECONDLY, we will exploit the obtained results, in particular:​

• Mathematical models to well represent kinematics and global interaction of each car,
• Numerical modelling to be efficient to qualify energy absorption, front face interaction area and Pulse of the tested car,
• Experimental results to be able to give global physical characteristics usable in car design.

THEN, we will discuss and answer to the following questions:​

• Limitations and disadvantages of theoretical and numerical approaches,
• What is the best relevant protocol to represent a C2C front crash and if it is reliable (comparison with others protocols and parametric studies),
• How to provide a better compatibility.

Finally, we will conclude and open the field.

The numerical study was conducted with the cooperation of ACTOAT company and the C2C tests at UTAC laboratory.