Refine Your Search

Search Results

Viewing 1 to 8 of 8
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

Vehicle Acceleration Modeling in PC-Crash

2014-04-01
2014-01-0464
The research reported here offers a validation of this capability, demonstrating that PC-Crash can be used to realistically model the build-up of a vehicle's speed under maximal acceleration. ...In the research reported here, PC-Crash 9.0 was used to model the full-throttle acceleration capabilities of three vehicles with automatic transmissions - a 2006 Ford Crown Victoria Police Interceptor (CVPI), a 2000 Cadillac DeVille DTS, and a 2003 Ford F150. ...In each case, the full-throttle acceleration of the vehicles modeled in PC-Crash showed good agreement with the acceleration of the real vehicles in our road tests.
Technical Paper

Measuring and Modeling Suspensions of Passenger Vehicles

2013-04-08
2013-01-0774
Numerical parameters describing suspension stiffness and damping are required for 3D simulation of vehicle trajectories, but may not be available. This paper outlines a simple, portable method of measuring these properties with a coefficient of variation of 5% on stiffness. 24 of 26 vehicles tested were significantly stiffer in roll than pitch, complicating analyses with models that don't include anti-roll. Suspension parameters did not correlate with static wheel load distribution, and damping coefficient did not correlate with natural frequency. Computer simulations of the speed required to initiate rollover in an S-curve were highly sensitive to the suspension parameters used. When pre-impact tire marks and rollover distance were considered, the simulations became almost insensitive to suspension parameters.
Technical Paper

Simulating Moving Motorcycle to Moving Car Crashes

2012-04-16
2012-01-0621
There has been little published research into simulating two-moving motorcycle-to-car collisions for the purpose of accident reconstruction. In this paper a series of two-moving crash tests were conducted to study collisions of this type. These tests used a range of speeds for the cars and the motorcycles involved, with perpendicular and oblique intersection collision impact configurations. The tests were then simulated with two popular crash simulation packages which were not designed to simulate motorcycles. The purpose of this study was to evaluate existing techniques and develop new techniques for simulating motorcycles in these software packages and then to examine the ability of each package to simulate a two-moving motorcycle-to-car crash. The results demonstrate that it is indeed possible to simulate a motorcycle in these packages and that both packages can simulate two-moving motorcycle-to-car crashes reasonably well.
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.
Technical Paper

Determination of Vehicle Velocities and Collision Location by Means of Monte Carlo Simulation Method

2006-04-03
2006-01-0907
In road accident analysis the problem of uncertainty of calculation results becomes essential particularly when modification of input values within the adopted ranges leads to diametric change of the answer to the question posed by the court of justice (e.g. “collision from the right-hand side of the center line” – “collision from the left-hand side of the center line”, or “the accident could have been avoided” – “the accident could not be avoided”). The aim of the paper was to present a method of collision reconstruction calculation using the principle of conservation of momentum, the principle of energy conservation, and the principle of kinetic energy and work equivalence (energy balance) (Marquard), taking into consideration Monte Carlo simulation method. The applicability of the method in determination of distribution function for vehicle collision velocities was proved and, what is more important, its practical uselessness in determination of collision location.
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.
X