Refine Your Search

Search Results

Viewing 1 to 14 of 14
Technical Paper

Effective Numerical Simulation Tool for Real-World Rollover Accidents by Combining PC-Crash and FEA

2007-04-16
2007-01-1773
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. At first, using a simplified full car model, sufficient conditions, such as additional velocity, required for a curb trip-over accident to occur, were derived from energy balance concept based on the same principle as critical sliding velocity (CSV) criterion. ...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.
Technical Paper

Soil Trip Rollover Simulation and Occupant Kinematics in Real World Accident

2007-08-05
2007-01-3680
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.
Technical Paper

EVALUATION OF THE EFFECTIVENESS OF PEDESTRIAN PROTECTION SYSTEMS THROUGH IN-DEPTH ACCIDENT INVESTIGATION, RECONSTRUCTION AND SIMULATION

2009-10-06
2009-36-0398
All of them are analysed in-depth and reconstructed with PC-Crash. The effects of the frontal structure of the vehicles and several active systems, such as BAS and Pedestrian Detection Systems, are evaluated. ...The paper includes the description of the methodology followed for a sample of approximately 140 pedestrian urban accidents in three cities in Spain (Madrid, Barcelona and Zaragoza) and the corresponding reconstructions done with PC-Crash. Then, a methodology to simulate the passive and active improvements (including pedestrian friendly structure, BAS and pedestrian detection system) is defined and applied to all the sampled accidents.
Technical Paper

A Pilot Study at National Highway-8 for On-Site Crash Data Collection and In-Depth Investigation in India

2017-01-10
2017-26-0001
The importance of on-site, in-depth accident research studies has been recognized internationally especially in developed countries. In order to address problems related to road safety, it is important to understand the epidemiology and causation of crashes. For this an in-depth investigation of the crash site, vehicles involved and injury details is required. Detailed crash information helps in analysing the events leading to crash and developing safety measures and/or intervention to reduce crashes. In order to pilot such an activity in India, an in-depth accident data collection activity had been carried out on national highway connecting Delhi to Jaipur (NH-8) for a duration of over a year by a joint team of IIT-Delhi and NATRiP. A total of 1220 road traffic accidents (RTA) notifications were received by the team, of which 186 cases were attended and detailed data was collected in a pre-decided format.
Technical Paper

Analysis of Finite Element Models for Head Injury Investigation: Reconstruction of Four Real-World Impacts

2005-11-09
2005-22-0001
Previous studies have shown that both excessive linear and rotational accelerations are the cause of head injuries. Although the head injury criterion has been beneficial as an indicator of head injury risk, it only considers linear acceleration, so there is a need to consider both types of motion in future safety standards. Advanced models of the head/brain complex have recently been developed to gain a better understanding of head injury biomechanics. While these models have been verified against laboratory experimental data, there is a lack of suitable real-world data available for validation. Hence, using two computer models of the head/brain, the objective of the current study was to reconstruct four real-world crashes with known head injury outcomes in a full-vehicle crash laboratory, simulate head/brain responses using kinematics obtained during these reconstructions, and to compare the results predicted by the models against the actual injuries sustained by the occupant.
Technical Paper

The Accident Research Unit Hannover as Example for Importance and Benefit of Existing In Depth Investigations

1994-03-01
940712
The In-Depth Investigations of the Accident Research Unit Hannover (Germany), which have been carried out since 1973 are described in the paper. The importance of the detailed analysis consists in the method, in the statistical approach and the continuous data collection over the years. The government as well as industrial manufacturers use this data. Since 1985 a statistical procedure including a mathematical weighting procedure has been applied. About 1000 cases per year are collected. In the paper, principal aspects in the technique of data collection, definitions of variables and possibilities of data usage are described. The limitations of in-depth investigations are discussed in principle, and demands for a worldwide level are pointed out.
Technical Paper

An Investigation into C-NCAP AEB System Assessment Protocol

2017-09-23
2017-01-2009
In order to speed up the development of vehicle active safety technology in China, C-NCAP plans to add AEB and AEB VRU system as assessment items in 2018. With the purpose of studying the assessment protocol of AEB system, we have carried out 400,000 km road information collection and then we acquired the statistics of the operation conditions of dangerous situations. Combined with the traffic accident data collected by CIDAS, we found that the dangerous situations that we usually met were mainly three types, that was CCRs, CCRm and CCRb. Based on what we mentioned above, we analyzed the three kinds of working conditions and gave the corresponding evaluation method. In addition, combined with the actual situation of China, we added two tests of error function. And then we took the actual road experiment of many models of vehicles.
Technical Paper

Computer Simulation of Steer-Induced Rollover Events Via SIMON

2011-04-12
2011-01-1122
This study examines through computer simulation the reconstruction of on-road vehicle rollover accidents induced by a driver steering maneuver. The three-dimensional vehicle dynamics software package SIMON is used to model a set of four test vehicles as six degree-of-freedom sprung masses with up to five degrees-of-freedom for each unsprung mass. The performance of the simulator's physics model, in the context of accident reconstruction, is evaluated through correlation with full-scale vehicle rollover tests. Of specific interest to this study was simulation of the trip phase of the vehicle's motion. The correlation parameters include vehicle trajectory, speed, heading angle, yaw rate, roll angle, roll rate and lateral acceleration. SIMON's capacity to accurately model the physics of a test vehicle's suspension and tire kinetics in the pre-trip and trip phases of motion is evaluated by modeling a set of four instrumented full-scale tests of steering-induced rollovers.
Journal Article

A Bayesian Approach to Cross-Validation in Pedestrian Accident Reconstruction

2011-04-12
2011-01-0290
In statistical modeling, cross-validation refers to the practice of fitting a model with part of the available data, and then using predictions of the unused data to test and improve the fitted model. In accident reconstruction, cross-validation is possible when two different measurements can be used to estimate the same accident feature, such as when measured skidmark length and pedestrian throw distance each provide an estimate of impact speed. In this case a Bayesian cross-validation can be carried out by (1) using one measurement and Bayes theorem to compute a posterior distribution for the impact speed, (2) using this posterior distribution to compute a predictive distribution for the second measurement, and then (3) comparing the actual second measurement to this predictive distribution. An actual measurement falling in an extreme tail of the predictive distribution suggests a weakness in the assumptions governing the reconstruction.
Journal Article

Injury Rates for Older and Younger Belted Drivers in Traffic Accidents

2012-04-16
2012-01-0573
This paper describes the correlation of a person's age to the risk of injury occurrence and the corresponding injury severity in traffic accidents. A representative sample of belted drivers was analyzed by using data from the German In-Depth-Accident Study (GIDAS) to investigate the influence of age on injury severity and special injuries to different body regions. The study focused on two age groups: 17-30 year old (younger drivers) and older drivers 50 year old and older (50+). The injury risk was described as a function of delta-v and injury risk curves based on Abbreviated Injury Scale (AIS). Furthermore, individual parameters like age and body mass index (BMI) as well as age and mass of the vehicle were considered. The statistical analysis was carried out using descriptive and multivariate statistics. This paper presents an overview of injury patterns of belted drivers and the probability of these drivers being injured in different accident scenarios.
Journal Article

Effects of Situational Urgency on the Perception and Response Time to Lateral Collision Hazards

2021-04-06
2021-01-0857
Situational urgency influences the perception and response time (PRT) interval of drivers confronting emergency collision hazards. However, a gap exists in our understanding of the movement characteristics of a collision hazard that directly contribute to a driver’s decision to initiate an evasive response. The aim of this experiment is to examine how the movement characteristics of intruding vehicles affect an oncoming driver’s PRT interval. Fourteen subjects viewed first-person perspective recordings of a simulated vehicle travelling along a two-lane roadway. Collision hazards were introduced when stopped vehicles positioned at intersecting roadways unexpectedly intruded into the subject’s path. Subjects were instructed to ‘brake’ their vehicle by pressing a keyboard space bar when they perceived that evasive actions were required to avoid a collision.
X