Designing a Bumper with Springs: Forces and Recoiling

[rajkumarsiva]

i found this question interesting and technically challenging... i want to know the different approaches for solving this given problem...

what are the factors to be considered while designing a bumper, with springs at its point of attachment with the car, so that the spring will compress and reduce the damage to the body of the car during a frontal collision... i want to know about the Engineering Mechanics approach of this above condition...

what are the forces that act on the spring and the car?

my friend said " there will be recoiling of the spring immediately after the collision " how to calculate and reduce the recoil of spring?

what will be the effect if the spring is replaced with hydraulics to absorb the impact ( similar to shock absorber ) ? and what are the forces that has to be considered while designing that hydraulic system?

 

[Navin A S]

The forces that act on the springs and car during a frontal collision include the force of impact from the other object, the spring force generated by the compressing of the spring, and the reaction force generated by the bumper. The force of impact is determined by the mass and velocity of the objects involved in the collision. The spring force depends on the stiffness of the springs and the amount of compression. The reaction force is generated by the bumper and depends on the material and design of the bumper. To reduce the recoil of the spring, one way is to use dampers or shock absorbers that absorb the energy of the impact. These devices work by converting the kinetic energy into heat energy. By using dampers, the spring can be compressed more slowly and the rebound force is reduced. Using hydraulics to absorb the impact is also a possibility. The forces to be considered in this case include the force of impact, the pressure generated by the hydraulic circuit, and the reaction force generated by the bumper. The force of impact is determined by the mass and velocity of the objects involved in the collision. The hydraulic pressure depends on the flow rate and the hydraulic resistance. The reaction force is generated by the bumper and depends on the material and design of the bumper.