Wrap Impact Pattern
Definition
A pedestrian impact sequence typical of passenger cars and low-profile vehicles: the lower limbs are struck, the body rotates forward and upward over the hood, and the head contacts the windshield or A-pillar before the body slides off.
- Context
- Pedestrian collision analysis
- Typical vehicles
- Passenger cars, low-profile vehicles
- Sequence
- Lower limb strike, forward rotation, head contact with windshield or A-pillar, slide off
Common questions
Why does vehicle profile determine whether a wrap pattern occurs?+
A low hood height, typical of passenger cars, strikes the pedestrian's legs first and allows the upper body to rotate up and onto the hood, producing the wrap sequence; a taller vehicle such as an SUV or truck tends to strike higher on the body and produce a different injury and throw pattern instead.
What does the presence of a wrap pattern tell a reconstructionist about impact speed?+
The head strike location on the hood or windshield, combined with the vehicle's known dimensions, can be used with established biomechanical models to estimate a range of likely impact speeds, though the wrap pattern itself is only one input among several used in that estimate.
Related terms
- Conspicuity
- The degree to which a pedestrian or cyclist is detectable against their background under the prevailing lighting conditions. It governs the detection...
- Fender Vault
- A variant in which the pedestrian contacts the vehicle's fender rather than the front face, resulting in a lateral throw to one...
- Head Wrap Distance (HWD)
- The distance along the vehicle's body surface from the primary contact point (usually the bumper) to where the pedestrian's head first contacts...
- Throw Distance
- The horizontal distance from the point of primary vehicle-pedestrian contact to the location where the pedestrian comes to rest. Combined with pedestrian...
- Vault Impact Pattern
- A pedestrian impact sequence typical of high front-end vehicles (SUVs, trucks): the pedestrian is struck in the torso or pelvis, the body...