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With the help of the stiffness based impact model of PC-Crash, input data for the multi body simulation code MADYMO was generated to evaluate occupant behavior in different vehicle-to-vehicle frontal impact scenarios.

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.

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.

During recent years the accident simulation program PC-CRASH was developed, which allows simulating the vehicles movement before, during and after the impact. ...The first one serves as an alternative for the optimizer tool and is included in the current version of PC-Crash. It gives reasonable insight in the variation of certain parameters in reasonable calculation time.

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.

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.

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.

Automotive occupant safety continues to evolve. At present this area has gathered a strong consumer interest which the vehicle manufacturers are tapping into with the introduction of many new safety technologies. Initially, individual passive devices and features such as seatbelts, knee- bolsters, structural crush zones, airbags etc., were developed for to help save lives and minimize injuries in accidents. Over the years, preventive measures such as improving visibility, headlights, windshield wipers, tire traction etc., were deployed to help reduce the probability of getting into an accident. With tremendous new research and improvements in electronics, we are at the stage of helping to actively avoid accidents in certain situations as well as providing increased protection to vehicle occupants and pedestrians.

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.

Five collisions were staged in order to evaluate PC-Crash, a simulation program used for investigating motor vehicle collisions. Both vehicles were moving in all of the staged collisions at 1:1 or 2:1 speed ratios. ...Firstly, collision parameters were calculated from measured data, and used as input to the PC-Crash collision model. Secondly, the post-impact vehicle paths and rest positions were used to determine the pre-impact speeds. ...Using the PC-Crash "Optimizer" to reconstruct the five collisions, the error in calculated pre-impact speeds of the ten vehicles ranged from-3.3 to +4.1 km/h.

The pedestrian model in PC-Crash is based on a multi-body system, where several bodies are interconnected by joints. Each of these bodies can have different properties to represent the different parts of the human body. ...Each of the different tests was reconstructed using PC-Crash and the pedestrian model and the significant difference between simulation results and crash tests are pointed out.

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.

During recent years the accident simulation program PC-Crash was developed. This software simulates vehicle movement before, during and after the impact, using 3D vehicle and scene models. ...A new interface has been developed between MADYMO® and PC-Crash so that, after the reconstruction of an accident, only a few additional parameters regarding restraint system, seat and occupant must be defined. ...A new interface has been developed between MADYMO® and PC-Crash so that, after the reconstruction of an accident, only a few additional parameters regarding restraint system, seat and occupant must be defined. PC-Crash then creates all necessary input files for MADYMO® and starts the occupant simulation.

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.

For the current paper the simulation models of PC-Crash [1], [2], [3] were used. In the last part of the paper several sample cases from crash tests and real life accidents are presented together with the result of the automatic optimization process.

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).

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.

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.