Particularly In low speed impacts.
- While SMAC has decades of proven validation and correlation with real world crashes using the rectangular definition of the vehicle,
- The timing of initial contact can be an issue to explain (forces before the rounded corners touch!).
- McHenry Software has modified msmac3D (on option choice) use the actual vehicle shape of each vehicle for contact detection.
With a rectangle representation, the vehicles detect contact at 0.024 seconds early and the DeltaVs are only slightly changed: figure below: comparison of old vs polygon definition, note the magenta rectangle is for comparison