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Current techniques that can be used to evaluate and analyse lateral impact speeds of vehicle crashes with poles/trees are based on measuring the deformation crush and using lateral crash stiffness data to estimate the impact speed. However, in some cases the stiffness data is based on broad object side impacts rather than pole impacts. Some have argued that broad object side impact tests can be used for analysing narrow object impacts; however previous authors have identified the fallacy of this premise. Publicly available side pole crash test data is evaluated in terms of crush depth impact speed and impact energy for six general vehicle types. A range of simulated pole impact tests at various speeds and impact angles were conducted using LS-Dyna and PC-Crash. Publicly available Finite Element Vehicle models of a 1996 Ford Taurus, a 1994 Chevrolet C2500 and a 1997 Geo Metro (Suzuki Swift) were used, providing relationships among impact speeds, crush depths and impact angles.

PC-CRASH is a windowso-based accident-reconstruction program which combines the simulation of pre-collision, collision, and post-collision dynamics for multiple vehicles in a graphical environment. This paper presents the trajectory and collision models on which PC-CRASH is based. PC-CRASH'S model for predicting the 3D kinematics of a vehicle's pre- and post-impact trajectory, which is based on a discrete- kinetic time forward simulation of vehicle dynamics rather than empirically-derived “spin-out coefficients”, is described. The tire-force model (which accommodates ABS), steer angle, wheel braking, weight shift, and suspension effects are introduced and the program's method of handling pre-impact yaw, braking, acceleration and pre-impact steering is outlined.

This research compares vehicle dynamic simulations in PC-Crash 8.2 to data recorded during instrumented handling tests conducted by Mechanical Systems Analysis Incorporated (MSAI). The handling tests, which were used to examine rollover stability in a 1998 and a 1999 Ford Explorer, involve rapid steering inputs at speeds between 30 mph [48.3 kph] and 60 mph 96.6 [kph]. Vehicle weight, center of gravity (c.g) position, suspension stiffness parameters, tire parameters, steering angle, and vehicle speed data provided by MSAI were used as input for the PC-Crash model. Lateral acceleration, roll angle, roll rate, and yaw rate vehicle response from PC-Crash were compared to the MSAI sensor data. The authors modeled 26 handling tests. PC-Crash appeared to be a reasonable tool for modeling gross vehicle response. In addition, PC-Crash correctly predicted whether or not the test vehicle would experience rollover instability in a majority of the cases.

Due to the increasing number of minivans and sport utility vehicles, rollovers have become more significant. As a result, various accident reconstruction programs have been developed to address this issue. To reconstruct rollover crashes, various requirements have to be fulfilled. These consist of: providing a simple method that is able to model three dimensional environments that often play a major role in rollovers. including suspension, tire and collision models must be provided. This is particularily important in the rollover initiation phase. including proper vehicle geometry and contact stiffness must be available. These are important for simulation of body contacts that affect the vehicle motion. This study focuses on one program, PC-CRASH. This program was developed to allow simulations of vehicle 3-dimensional movements before, during and after the impact. The study also discusses the physical background of the models, their capabilities as well as their limitations.