Now onto the original Posting:
Depending on the nature of the physical evidence in pole/tree collisions, two separate analytical approaches may be applicable to approximate vehicle speed and impact severity.
- One approach is based on the vehicle motions preceding and following the collision.
- In cases where motions subsequent to the impact are sufficiently defined, work-energy relationships can be applied to approximate the work done against motion resisting forces and,thereby, determine the linear and angular velocities at separation from the pole/tree. The principle of conservation of angular momentum can then be used to determine the corresponding components of vehicle velocity at the point of impact with the pole/tree.
- The nature and extent of vehicle crush can serve as a separate basis for approximating vehicle speed and impact severity. Empirical crush properties, combined with vehicle specifications, and the degree of collision offset, can be applied to approximate the extent of energy absorption by vehicle crush and the corresponding impact speed-change.