ABSTRACT
This paper is concerned with modelling the level of shock sustained by a hard object when impacting on a flat surface. Analytical and experimental investigations at this stage of the study are mainly based on dropping steel pin-balls onto a rubber mat. In these tests, the accelerations (shock) on the pin-ball were logged from the instance of initial contact with the rubber up to the point of maximum indentation into the rubber. The acceleration-displacement relationships defining the resistance to indentation were then obtained. One of the interesting and important observations from the experimentation was that resistance to indentation was lower under dynamic conditions (of a dropped pin-ball) than static conditions (of the pin-ball gently pushed into the rubber mat). Force-displacement relationships for both conditions have been reproduced by finite element simulations which provide clues to the explanation for the observed phenomenon.
