Delta-V
Definition
The change in vehicle velocity during the crash event, recorded by the EDR as a time-history. It is the integral of the deceleration pulse and is the primary injury-risk metric used by biomechanical analysts.
- Primary role in crash analysis
- Biomechanical metric used to assess occupant injury risk
- Data source
- Event data recorders (EDRs) record Delta-V as a time-history during the crash
Common questions
What is Delta-V and why does it matter in crash investigation?+
Delta-V is the change in velocity a vehicle experiences during a collision. It is the primary metric used by biomechanical analysts to estimate injury risk to occupants because the severity of injuries is closely tied to the total velocity change the vehicle undergoes during the impact.
How is Delta-V measured or recovered at a crash scene?+
Delta-V is recorded automatically by event data recorders (black boxes) in modern vehicles as a time-history during the crash event. Investigators can also reconstruct it from accident reconstruction physics using vehicle damage, final rest positions, and other evidence.
Is Delta-V the same as deceleration?+
Not exactly. Deceleration is the rate of speed change at a moment in time, while Delta-V is the total change in velocity over the entire collision interval. Delta-V is the integral of the deceleration pulse, meaning it sums up all the deceleration that occurred during the crash.
Related terms
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Explained in these topics
- Accident Reconstruction PhysicsThe change in velocity experienced by a vehicle during the collision interval. It is the primary injury-risk metric in biomechanical analysis and is also recov...
- Event Data Recorders and Black-Box AnalysisThe change in vehicle velocity during the crash event, recorded by the EDR as a time-history. It is the integral of the deceleration pulse and is the primary i...