I got to thinking about the idea of reinforcing the "crumple zone" of thin walled tubing by pressing a ridge along the tubes axis.  Effectively the round tube graduates into a tear shape at the ends, increasing the rigidity of the surface of the steel where it would most likely buckle and cave in in the case of a head-on collision with a static object.  This is the initial test I did as well as the die and v-block that did the work.