In order to accomplish effective protection of vehicle occupants during collisions, much care has been paid to vehicle safety parameters such as crashworthiness, the performance of occupant restraints, the energy absorption characteristics of the interiors and so on.

The seat belt is the most popular restraint system and its effectiveness has been demonstrated through accident investigations and many kinds of tests. However, it is now always easy to evaluate seat belt anchorage location without conducting crash tests or math-model simulations.

We have developed a new method to estimate this effect, which can easily relate the seat belt anchorage location to occupant injury level by adopting the "Anchorage Coefficient". This coefficient can be easily calculated by using a simple formula based on the geometric location of seat belt anchorages relative to the occupant.

Validity of the method has been confirmed through various series of sled tests, and some applications have also been available with satisfactory results.