Is it possible to calculate Impact Force non-experimentally?

[spanton89]

Hi,

I am trying to calculate the impact force of a rubber weight falling on a rubber surface. I am aware that to calculate impact force, I need to know the amount of deflection after impact. Is there a way to calculate this, using material parameters, rather than experimentally?

Thanks in advance.

 

[edgepflow]

You could roughly estimate by modelling the rubber ball as a linear spring:

F_spring = k y

where k is the "spring constant" for rubber and y is the vertical deflection.

The energy stored in the spring is:

U_spring = (1/2) k y^2

If the rubber weight of mass m is dropped from height h, its PE = mgh

So,

U_spring = mgh and

y_spring = sqrt (2mgh / k)

The velocity on impact is:

v = sqrt (2gh)

Assuming constant decleration, the impact force is:

F_impact = v^2 / 2y