We use several specialized computer programs to analyze and simulate highway accidents. These programs can help us determine what happened in an accident and also tell us how severe it was by computing "delta V"- the speed change through the impact phase of the accident. Simulation and analysis programs should be distinguished from animation programs which are sometimes used to produce the final graphic representation of the computational results. Animation can be very expensive while analytical programs should prove cost effective in any case in which they can be used. Among the programs we use are:
Crash 3 is a program that computes "delta v" from known vehicle stiffness parameters and damage measurements on the vehicles involved in collision. Crash 3 has been validated by comparing computed results with data generated by staged test accidents. It is used by the Federal government in accident severity studies. Crash 3 essentially computes the energy required to produce the measured damage on the vehicles and then computes the speed changes associated with the loss of kinetic energy indicated by the damage.
EDSVS is a simulation program used to analyze vehicle trajectories. Inputs include vehicle size and weight, initial position and velocity and tire properties. The program then computes the vehicle's path (trajectory) in response to the drivers braking and steering inputs. EDSVS is useful for analyzing rollover events, loss of control, and post-impact trajectories.
EDVTS is a program similar to EDSVS but it is used to analyze the behavior of vehicles pulling trailers, including semi-trailer rigs. EDVTS can be used to predict or analyze rollovers, jackknifing and braking performance of vehicles pulling trailers.
We continually review accident reconstruction software and are familiar with most of the programs now available. We can assist clients with the analysis of any computer simulations or reconstructions that are presented by adverse parties. Services here include reviewing and evaluating validation studies and input files, output interpretation, etc.
back to the TECHNICAL SERVICES Home Page...