Search Results

This paper explores the dynamics of rollover crashes and examines factors that influence the severity of the roof-to-ground impacts that occur during these crashes. The paper first reports analysis of 12 real-world rollover accidents that were captured on video. Roll rate time histories for the vehicles in these accidents are reported and the characteristics of these curves are analyzed. Next, the paper uses analytical modeling to explore the influence that the trip phase characteristics may have on the severity of roof-to-ground impacts that occur during the roll phase. Finally, the principle of impulse and momentum is used to derive an analytical impact model for examining the mechanics of a roof-to-ground impact. This modeling is used to identify the influence of various impact conditions on the severity of a roof-to-ground impact.

The vehicle dynamics of all scenarios from the database will be simulated in PC-Crash, an accident-reconstruction software. Since the brake assist is obligatory from 2012 on, the system and its effect on each single accident scenario will be modeled.

Nearly 50,000 Americans die from brain injuries annually, with approximately half of all Traumatic Brain Injuries (TBI) being transportation-related. TBI is a critical and ever-evolving safety topic, with equally important components of injury prevention, consequences, and treatment. This book is part of a 3-volume set which presents a comprehensive look at recent head injury research and applies protective strategies to various injury scenarios, such as passenger vehicles, sports, and blast injuries, or to a particular demographic group, such as children or seniors. This volume features 14 technical papers. Editor Jeffrey A. Pike has selected the most relevant technical papers spanning the early 1990s through the beginning of 2011, including several older papers which provide an essential historical perspective. Each volume in the series also includes a table of references arranged by topic and a new chapter tying together anatomy, injury, and injury mechanism topics.

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.

Taking the pedestrian-vehicle accidents in the China in-Depth Accident Study (CIDAS) database as a sample case, 13 accidents morphological parameters were selected from three aspects: human, vehicle and environmental factors, and their depth analysis was carried out to obtain their distribution law through the card. The chi-square test and logistic regression method are used to analyze the correlation between the injury severity of pedestrians and other accidental morphological parameters in pedestrian-vehicle accidents. The results show that there is no significant correlation between gender/season and injury severity of pedestrians. The age of pedestrians and the collision speed is the strongest correlation with injury severity of pedestrians.

Next, simulations in PC-Crash were performed, and the results were compared with those obtained in experiments.

Each accident in this sample is modeled numerically by the simulation tool PC-Crash. In parallel, a model representing the function of an AEB system has been established.

The analyst may often turn to accident reconstruction software such as the various versions of SMAC and some impulse-momentum approaches like PC-Crash and VCRware. Within these programs there is a user-input variable often referred to as the inter-vehicle friction coefficient.

HVE 1 and PC-Crash 2 have been the subject of numerous SAE papers. Both programs have been offered to reconstructionists for the purpose of analyzing vehicle accidents and presenting the resulting motions in 3D graphical form.

However, based on investigated pedestrian collisions, the location where the pedestrian has engaged with the vehicle can and does significantly influence the throw distance (and projection) and subsequent impact speed analysis. PC-Crash was used to simulate multiple pedestrian impacts at varying speeds and vehicle impact locations, creating pedestrian throw distance impact speed contour plots.

Understanding of events within the history of a crash, and estimation of the severity of occupant interior collisions depend upon an accurate assessment of crash duration. Since this time duration is not measured independently in most crash test reports, it must usually be inferred from interpretations of acceleration data or from displacement data in high-speed film analysis. The significant physical effects related to the crash pulse are often essential in reconstruction analyses wherein the estimation of occupant interior “second collision” or airbag sensing issues are at issue. A simple relation is presented and examined which allows approximation of the approach phase and separation phase kinematics, including restitution and pulse width. Building upon previous work, this relation allows straightforward interpretation of test data from related publicly available test reports.

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.

These predictions were generated by directly integrating the VCH data and by using the VCH data as inputs to PC-Crash simulations. The predicted positions and headings were then compared to the actual position and heading data measured using differential GPS synchronized to the VCH data record.

For automotive engineers involved in crash reconstruction and analysis, a knowledge of basic accident reconstruction principles and techniques is essential, but often insufficient to answer all of the questions posed by design engineers, regulators, and lawyers. This seminar takes participants beyond the basics of accident reconstruction to physical models and analysis techniques that are unique to the reconstruction of single-vehicle rollover crashes.

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.

The total number of persons severely and fatally injured in road traffic accidents has reduced considerably in recent decades. However, the number of motorcyclists involved in accidents has not reduced to the same extent, and some countries have even recorded an increase. The aim of this study is to analyse the circumstances of motorcycle accidents in Germany involving vehicles with a cubic capacity of over 125 cm3 with particular reference to severely or fatally injured riders. An analysis is to be made of the characteristics and patterns of injuries suffered by the most severely injured motorcyclists and proposals developed for injury prevention. The study included accident data from 464 motorcycle accidents collected in Hanover and Dresden between 2010 and 2015 by an academic research team in the course of the GIDAS project (German In-Depth Accident Study). This data represents a statistically representative sample from real accidents occurring in Germany.

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.