If this is incorrect, could you point me in the right direction to develop a correction factor.
A: Couple of things:
Closing Speed:
- DeltaV is not normally used with closing speed.
From our McHenry Accident Reconstruction Book (currently out of print):- Closing Speed: This term is used to indicate the speed of approach of two colliding bodies immediately before contact. It may further be defined as the algebraic sum of the velocity components of two vehicles along a reference line connecting their centers of gravity, and it is generally expressed in miles per hour. For a simple example, the closing speed in a central rear-end collision is the difference between the forward velocities of the two involved vehicles.
Closing speed, by itself, does not provide a complete measure of impact severity, since it does not include an indication of the mass ratio of the two colliding bodies. For example, with a given closing speed, a heavy truck or a freight train will obviously produce a more severe impact for its collision partner than would a subcompact automobile.
The terms impact speed and closing speed are sometimes used interchangeably
- Closing Speed: This term is used to indicate the speed of approach of two colliding bodies immediately before contact. It may further be defined as the algebraic sum of the velocity components of two vehicles along a reference line connecting their centers of gravity, and it is generally expressed in miles per hour. For a simple example, the closing speed in a central rear-end collision is the difference between the forward velocities of the two involved vehicles.
- Please see our paper entitled RICSAC97-A Reevaluation of the Reference Set of Full Scale Crash Tests, SAE Paper 97-0961
which includes- “A new method of analyzing accelerometer data from arbitrary sensor positions, on the basis of discrete measures of the vehicle responses rather than complete time-histories, is defined”.
That may help you resolve ACM data to the CG (since an ACM is basically an accelerometer)
- “A new method of analyzing accelerometer data from arbitrary sensor positions, on the basis of discrete measures of the vehicle responses rather than complete time-histories, is defined”.
- In the notes you’ll not that if L (the distance from the point of application of the force and the CG) is close to B (the distance from the CG to the rear wheel) then K**2 would be sufficiently close to A * B such that yaw rotations would be about a point near the right front wheel so confirming your observation