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In this paper, the current capabilities of Pycrash are illustrated and its accuracy is assessed using matching PC-Crash simulations performed using PC-Crash. The results indicate that Pycrash is well-equipped to perform fundamental accident reconstruction analyses, including impact related effects, but its simplified suspension model is a limitation.

Sensor signals are derived using the PC-Crash tool, and characteristic features are identified. Insights derived from these events can aid in development of robust rollover detection algorithms and calibrations.

Development of crash avoidance systems and active safety systems must not be only based on experimental knowledge. The goal is to provide an efficient answer to still unsolved severe real-world car crashes which occur despite enhanced passive safety devices. This requires to know precisely the pre-crash conditions during about 3 to 10 seconds before impact. The paper describes the multidisciplinary systemic approach leading to the comprehensive methodology used in accident reconstruction in order to determine the best scenario, and to assess initial car speeds, paths and events in the different phases of the accident. This has already been carried out for about 400 car crashes with car occupant injuries (including 6% fatal and 10% severely injured). The necessity of collecting data on the spot of the crash scene is highlighted. Three well-trained investigators are involved.

An optimizer tool in PC-Crash is designed to minimize reconstruction time and error by automatically varying a selected number of impact parameters, comparing the resulting simulation for each combination of parameters with the actual incident. ...Twenty staged collisions were reconstructed with the optimizer tool in PC-Crash. These staged collisions had been previously reconstructed with a combination of manual linear momentum calculations combined with the trajectory model in an earlier version of PC-Crash. ...These staged collisions had been previously reconstructed with a combination of manual linear momentum calculations combined with the trajectory model in an earlier version of PC-Crash. Differences between the reconstruction simulations and the actual collisions, and methods for minimizing reconstruction errors, are discussed.

First, the roundabout driving safety evaluation based on the rollover propensity index calculated with the tire loads was performed through various PC-Crash simulation analysis. And, using the Taguchi method, which is a representative DOE method, major factors affecting the rollover index were set by type and the sensitivity analysis results were quantitatively obtained.

The software packages included in the studies presented in this paper are HVE (SIMON and EDSMAC4), PC-Crash and VCRware. This paper will present the results of the study, conducted using DOE, involving these models.

PC-Crash simulations of staged collisions require dozens of parameters describing vehicle and impact parameters.

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.

In this work, we focused on the trip-over type, which occurs most frequently, and performed simulations to reproduce real-world rollover accidents by combining PC-Crash and FEA. Soil trip-over simulation was carried out based on real world accidents. Based on rigid body dynamics, PC-Crash software was chosen to make an accident reconstruction analysis of some selected cases chosen from an accident database (NASS-CDS). ...Based on rigid body dynamics, PC-Crash software was chosen to make an accident reconstruction analysis of some selected cases chosen from an accident database (NASS-CDS). ...The output of this PC-crash simulation was then used as the initial input conditions (i.e., speed, deceleration, etc.) of a detailed finite element analysis.

The protection of children in cars is improving with the increasing use of better designed restraint systems. Indeed, when children are correctly restrained in appropriate child restraint systems (CRS) they are sufficiently well protected in moderate frontal impacts. However, the levels of protection afforded in severe frontal impacts and lateral crashes has needed further attention. The CREST project, funded by the European Commission, was initiated to develop the knowledge on the kinematics behavior and tolerances of children involved in car crashes. The final aim of the project is to propose enhanced test procedures for evaluating the effectiveness of child restraint systems (CRS). The method used in this project was to collect data from accident investigations and from reconstructed crashes in order to determine the physical parameters (measured on dummies) which correspond to various injury mechanisms, and is described in ESV 2001 - paper n°294.

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. ...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.

Knowledge about vehicle rolling resistance is required to calculate speed loss of accident vehicles during portions of their pre-impact and post-impact trajectory when they are not braking or sliding directly sideways. The accuracy of assumed rolling resistance values is most important in accidents with long post-impact roll out distances. Very little hard data are currently available1 and the accident reconstructionist must usually make estimates of drivetrain losses and normal and damaged tire rolling resistance to determine overall vehicle rolling resistance. In the first part of this study, the rolling resistances of various vehicles with different drive configurations are determined, based on accurate measurements made with a 5th wheel. In the second part, sensitivity analyses are done with PC-Crash2, a computer simulation program, to determine what effect the error in assumed rolling resistance has on speed calculations for various types of post-impact trajectories.

Using the PCM philosophy and including 5 seconds before the accident in the crash analysis combined with the driving behaviours of the vehicles out of PC-Crash, it is possible to analyse, whether or not a sensor system would have been able to recognise the dangerous situation in time to avoid or mitigate the accident.

This paper describes in detail the extension of the discrete kinetic time forward simulation program PC-Crash to deal with multi-body-systems. As one application of this model pedestrians have been modeled.

The program PC-CRASH was developed for the reconstruction of vehicle accidents and considers pre-impact, collision and post-impact phases. ...The present paper describes the physical and mathematical model which was added recently to PC-CRASH in order to enable the simulation of the dynamic behavior of articulated vehicles (with both single and double axle semi-trailers and with steered trailers).

Furthermore, 183car-to-pedestrian cases, with detailed information regarding accident vehicles, pedestrians and environment, were reconstructed using PC-Crash. A hypothetical autonomous braking system would activate when the pedestrian successfully detected by the sensing system and then new impact speeds will be calculated.

Parameters such as vehicle weight, sliding friction factor, motorcycle sliding trajectory, and yaw trajectory will be accounted for in each PC-Crash simulation. All tests were simulated using a 2D and 3D motorcycle model in PC-Crash. Additionally, calculated averaged slide-to-stop decelerations and slide-to-stop distances based on physical evidence were used and verified in the PC-Crash simulation. ...PC-Crash is an accident reconstruction program that enables the user to analyze vehicle collision dynamics and trajectory models. ...This research paper presents the utilization of PC-Crash to analyze motorcycle slide-to-stop dynamics. For this study, existing motorcycle slide-to-stop data from SAE 2019-01-0426 will be simulated and analyzed in PC-Crash.

PC-Crash is a Windows™ - based accident reconstruction program developed in Graz, Austria by Dr. Hermann Steffan. ...Hermann Steffan. PC-Crash collision analysis results are compared with previously published staged collision data. ...The staged collisions were reconstructed using PC-Crash and the trajectories were compared to actual measurements of the skid marks and rest positions.

PC-Crash is an accident reconstruction program allowing the user to perform simulations with multibody objects that collide or interact with 3D vehicle mesh models. ...The current motorcycle models in PC-Crash are generic and do not resemble a sport bike type motorcycle. They are only globally scalable such that you cannot adjust length, width, or height independently. ...The test results were compared to parameters calculated in PC-Crash. Results such as Delta-V, yaw rate and overall post impact trajectories of the motorcycle, rider and movement of the target vehicle were compared to the data from the instrumented test vehicles.

During recent years the accident simulation program PCCRASH was developed, which allows to simulate the vehicles movement before, during and after the impact. ...Within SAE 1999-01-0444 a new coupling interface of PC-CRASH and the software MADYMO, developed by TNO in the Netherlands was published. During last year's publication only few validation cases, mainly related to rear end impacts could be demonstrated. ...One major emphasis was set on the influence of the crash pulse, which cannot be derived in PC-CRASH. In this way the paper demonstrates the possibilities as well as the limitations of the numerical model.