A Preliminary Analysis consists of a review of the materials provided
by our staff collision analysts. The Traffic Collision Report
is summarized and any available photographs are analyzed. Diagrams
of vehicle damage are prepared and preliminary calculations of
vehicle speed and paths are determined. This analysis results
in initial findings that are communicated to the client along
with any additional work items that are necessary to proceed with
the Analytical Reconstruction.
A mapping crew utilizes an electronic distance measurement (or
EDM) device to take accurate measurements of the roadway and overall
scene of the accident. Any remaining physical evidence, such as
skid marks or gouges are identified and can be used to determine
placement of the vehicles involved. If necessary, additional three-dimensional
data may be collected for the purpose of illustrating three-dimensional
issues such as view obstructions, line of sight analysis or for
use in a computer animation of the events of the accident.
This process can be done through the use of forensic mapping
equipment (an EDM as previously defined) with which a detailed,
accurate three-dimensional model is created by capturing points
on the vehicle with a data collection device. Forensic mapping
is particularly effective when there is extensive damage done
to a vehicle, as it is a useful means by which to determine crush,
which can correspond to vehicle speed. Alternately, the dimensions
of a vehicle can be recorded through a series of hand measurements.
Both processes involve photography in addition to the measurement
procedure. The data collected by either of these processes is
then used to define items such as center of gravity, front and
rear overhang, track width as well as numerous other elements
all of which define what the motion path of a particular vehicle
would be in a collision. This information then becomes one of
many key elements in performing an accident reconstruction. A
simple to moderate vehicle documentation will take about four
hours and requires a two-person crew. Heavily damaged vehicles
will require additional time. Once the data has been collected,
it is transferred from the data collection device to the computer
system. These "points" of information are then refined and corrected
if necessary and then transferred into a computer aided design
(CAD) program in order to create a three-dimensional model of
the vehicle. This model is uses in the analysis of the accident
to determine the angle at which the vehicles came together and
to align the vehicles with physical evidence collected at the
scene.
We perform an objective page / line summary for depositions of
non-experts.
