Does SMAC neglect tire forces during the collision impulse?

[MSI]

Q: I recently read a paper on SMAC by a commercial SMAC vendor which included the statement:

• The SMAC "simulation assumes that during impact the collision forces are much greater than the tire-road forces and, therefore, tire-road forces are neglected during the collision impulse'

Does SMAC neglect tire forces during the collision impulse?

A: NO! That statement about SMAC is 100% in ERROR. That statement demonstrates that the commercial SMAC vendor does not understand how SMAC works. The following is from one of the early 1973 publications on SMAC:

"Computer Program for Reconstruction of Highway Accidents"
From 1973, SAE paper 73-0980 by Ray McHenry of McHenry Software:
(red underline added below)

collision and tire forces.png (208.23 KiB) Viewed 846 times

Not sure where your commercial vendor got that erroneous idea.
SMAC is one of the few programs that DOES, and always has, included modeling the tire forces during the collision impulse.