EDCRASH

Name	EDCRASH (Engineering Dynamics Corporation Reconstruction of Accident Speeds on the Highway)
Description	EDCRASH is an analysis of single or two vehicle accidents. It is based on the Calspan Reconstruction of Accident Speeds on the Highway (CRASH) and includes refinements and enhancements provided by NHTSA as well as Engineering Dynamics Corporation. The program determines the conditions of impact, including the speed of the vehicles at impact and the severity of the impact, using information obtained from vehicle and accident site inspections. EDCRASH is a 3-degree of freedom (yaw plane) analysis; suspension effects are ignored. For oblique collisions, the impact phase is analysed using the conservation of momentum; for collinear impact, vehicle damage is used in conjunction with crush stiffness tables developed from impact testing. The impact-to-rest phase is analyzed using energy methods, with extensions allowing for the effects of vehicle rotation and curved trajectory. The impact-to-rest phase may also be subjected to a trajectory simulation to confirm the results.
Input	Title, Class, Weight, Collision Deformation Classification, Principal Direction of Force, Stiffness, Impact and Rest Positions, Pre-impact Sideslip, Impact-to-rest Path Description (sustained contact, end of rotation, point on curve, rotation direction), Tire/Road Data (friction, wheel lock-up, trajectory simulation data), Vehicle Damage (width, profile, center of damage). The user has the option of entering Vehicle Data (Dimensional, Inertial, Tire and Crush Stiffness Properties) if desired.
Output	Velocity at Impact (longitudinal, lateral), Velocity Change (longitudinal, lateral), Separation Velocity (longitudinal, lateral, angular), Closing Velocity, Force/Direction of Impact, Energy Absorbed by Damage, Trajectory Simulation Results, Vehicle Dimensional and Inertial Properties, Echo of Accident Site, Tire/Road, and Damage Data.
Graphics	Site Drawing (vehicle impact and rest positions, end of rotation and point on curve) with simultaneous display of key data; Vehicle Damage Profiles (display of vehicle damage outline and key damage data).
Other Features	Input session logic checks data as it is entered; the user may change any data prior to execution; the user may request a detailed explanation of the required input, including answer format and sample answer; rerun and file-saving options. Output session displays data in a complete or abbreviated format; routes the results to the screen or printer; extensive warning messages and validity checking; provides input for EDSMAC and EDHIS; file-saving option.