Q: On the
INCR forum a topics was brought up where a question was posted:
- A motorcycle with substantial damage seems in contrast to the vehicle it struck where the EDR only recorded a lateral DeltaV of 7 MPH and a longitudinal DeltaV of 6 MPH. Wondered how can that be?
- Mentioned in responses was an EDR2 course where equations were presented to help the analyst adjust the DeltaV to the centroid of impact on the hit vehicle taking into consideration ground forces.
They included this list of external forces sources:
- 2 types of Ground forces.png (269.59 KiB) Viewed 8758 times
That brings up two important items to consider with EDRs:
- 'Effects of Tire Friction/External Forces on EDR Data and
- '"Effective Mass" in DeltaV Calculations'
A: We responded with some related links/references:
- I add a couple of related references related to the question brought up on
- 'what effect does braking/external forces have on the DeltaV recorded by EDRs'
We addressed it back in 2020 on our McHenry Forum with the topic:
And a couple recent papers from 2022 Collision Magazines addressing the issue:
Also saw in this topic a question on offset/etc which Raymond R. McHenry coined as 'Effective Mass' (as part of Damage Analysis) see:
Please let us know if any questions/comments/etc