PC-Crash Software Research Articles

Numerical reconstruction for a multi-car collision dynamics

In order to accurately determine the collision relationship of each vehicle in complex traffic accidents, combined with the scene trace and accident simulation, an accident reconstruction method is proposed. The method examines the accident scene and the accident vehicle which can forecast the accident process in advance and determines the approximate vehicle collision speed by the dynamics method. Then, based on the pre-determination, the PC-Crash software is used for accident reconstruction to more accurately determine the accident scenario and the vehicle collision parameter. This method was used in a four-car serial collision on a rainy highway. The collision information of the accident cars was read using Bosch's data reading tool Crash Data Retrieval (CDR). The results showed that the method can accurately reconstruct complex traffic accidents and provide an effective solution for determining the collision relationship of vehicles and the responsibility for traffic accidents.

Numerical reconstruction for a multi-car collision dynamics

In order to accurately determine the collision relationship of each vehicle in complex traffic accidents, combined with the scene trace and accident simulation, an accident reconstruction method is proposed. The method examines the accident scene and the accident vehicle which can forecast the accident process in advance and determines the approximate vehicle collision speed by the dynamics method. Then, based on the pre-determination, the PC-Crash software is used for accident reconstruction to more accurately determine the accident scenario and the vehicle collision parameter. This method was used in a four-car serial collision on a rainy highway. The collision information of the accident cars was read using Bosch's data reading tool Crash Data Retrieval (CDR). The results showed that the method can accurately reconstruct complex traffic accidents and provide an effective solution for determining the collision relationship of vehicles and the responsibility for traffic accidents.

Assessing performance of collision mitigation brake system in Chinese traffic environment

Advanced driver-assistance systems such as Honda’s collision mitigation brake system (CMBS) can help achieve traffic safety. In this paper, the naturalistic driving study and a series of simulations are combined to better evaluate the performance of the CMBS in the Chinese traffic environment. First, because safety-critical situations can be diverse especially in the Chinese environment, the Chinese traffic-accident characteristics are analyzed according to accident statistics over the past 17 years. Next, 10 Chinese traffic-accident scenarios accounting for more than 80% of traffic accidents are selected. For each typical scenario, 353 representative cases are collected from the traffic-management department of Beijing. These real-world accident cases are then reconstructed by the traffic-accident-reconstruction software PC-Crash on the basis of accident-scene diagrams. This study also proposes a systematic analytical process for estimating the effectiveness of the technology using the co-simulation platform of PC-Crash and rateEFFECT, in which 176 simulations are analyzed in detail to assess the accident-avoidance performance of the CMBS. The overall collision-avoidance effectiveness reaches 82.4%, showing that the proposed approach is efficient for avoiding collisions, thereby enhancing traffic safety and improving traffic management.

Reconstruction of Vehicle-pedestrian Collision Road Traffic Accidents Based on PC-Crash Software.

Objective To discuss the application value of vehicle-pedestrian collision road traffic accidents reconstruction based on PC-Crash software in forensic identification. Methods A case of vehicle-pedestrian collision was chosen based on a tachograph, then PC-Crash software was applied to construct a vehicle-pedestrian collision model, and reconstruct the vehicle-pedestrian collision road traffic accident. Finally, the process of vehicle-pedestrian collision was reproduced. Results In accident reconstruction, when the car speed was lower than 50km/h, the landing point of the pedestrian after collision was in the front of the car. When the car speed was higher than 50 km/h, after collision, the pedestrian flipped towards the car roof and landed behind the car. With the increase of vehicle speed, throwing distance of the pedestrian increased continuously. When the vehicle collision speed reached 60 km/h, the experimental results in this case were basically consistent with the actual situation of the case. Head acceleration of the pedestrian was at the maximum （1 655.70 m/s2） at 0.080 s. Chest acceleration of the pedestrian increased from 597.63 m/s2 to the peak 675.52 m/s2 at 0.055-0.060 s. Tibia acceleration of the pedestrian increased from 759.26 m/s2 to the first peak 1 367.06 m/s2, then reached the maximum speed （1 718.19 m/s2） at 1.225 s. Conclusion The process of vehicle-pedestrian collision road traffic accidents can be reconstructed based on PC-Crash software under a situation of limited conditions, and can further clarify the speed of the vehicle, the location and degree of human body injury as well as the mechanism of damage of the pedestrian in the accident. Therefore, PC-Crash software has a certain practical value in forensic identification of road traffic accidents.

Study regarding the influence of passive safety systems on the occupant in the case of Automatic Emergency Braking System activation

The aim of this paper was to analyze the injury level of the occupants of a vehicle in the case using the AEB system to reduce the velocity of a front-back collision by utilizing virtual simulations in PC-Crash software. This was achieved by conducting simulation at different velocities and 3 passive safety systems configurations. The velocities tested were 70, 75 and 80 km/h to observe the speed reduction of the vehicle in a collision by the AEB system. Also, the occupant was configured in 3 types of scenarios, when the occupant does not have the seatbelt or airbag, when only the seatbelt is used and when both seatbelt and airbag are activated. The results revealed a great speed reduction by the AEB system, reducing the impact velocity and also the occupant presented a reduced injury risk when both passive safety systems are active.

Research Progress of Traffic Accident Reconstruction Technology Based on PC-Crash Software

With the development of the computer simulation technology and the digital simulation technology, the traditional calculation method has been gradually replaced by the digital method to deal the road traffic accident scene and analyse the process. The PC-Crash software simulation system can reconstruct the traffic accidents within 32 vehicles, and the accuracy of reconstruction has been fully verified, which is widely used by the transport police department and the accreditation agency. In this paper, the research of road traffic accident reconstruction using PC-Crash software is reviewed, and the application of road traffic accident reconstruction technology based on PC-Crash software and some existing problems in forensic practice are discussed, which provides reference for the research and identification of road traffic accident simulation and reconstruction and theoretical basis for accident treatment.

Research on Human Vehicle Accident Reconstruction Based on AEB System

Accident reconstruction refers to the physical activity of inferring the accident process according to the traces left by the accident participants, the final posi-tion, the participation in the car damage and the injury of the participants, and then the testimony of the participants and eyewitnesses. It not only provides a basis for the identification of the faults of both parties, but also provides data support for accident prevention and vehicle active safety analysis and research. This paper studies the basic theory of accident reconstruction, and uses PC-Crash software to reconstruct 30 accidents, and obtain parameters such as vehicle, human motion parameters and relative position before, during and after collision.

Research on Vehicle Accident Simulation Based on Multi-source Information Combined

The real vehicle accident case is selected, and accident multi-source data such as vehicle damage deformation, vehicle final position, scene ground traces, scattered objects, occupant injury and so on are combined in the paper. The vehicle model and road environment model are built on the basis of PC-Crash software. In order to reproduce real accident, the vehicle collision dynamics and kinematics parameters are analyzed by vehicle dynamics simulation, moreover, occupant collision injury and its cause involving vehicle accident are analyzed through human trauma assessment software. The methodology based on multi-source accident information combined in this paper is applied on real accident and validated the practicality and effectiveness on simulation and reconstruction, which is of great value in research on vehicle accident.

Vehicle Speed Determination in Case of Road Accident by Software Method and Comparing of Results with the Mathematical Model

Abstract The paper addresses the problem to vehicle speed calculation at road accidents. To determine the speed are used the PC Crash software and Virtual Crash. With both methods are analysed concrete cases of road accidents. Calculation methods and comparing results are present for analyse. These methods consider several factors such are: the front part of the vehicle, the technical feature of the vehicle, car angle, remote relocation after the crash, road conditions etc. Expected results with PC Crash software and Virtual Crash are shown in tabular graphics and compared in mathematical methods.

Methods for calculating intervals of reconstructed results in traffic accidents with different types of interval traces

In order to obtain more effective uncertainty analysis methods for analyzing uncertainty of a reconstructed result in a traffic accident with different types of interval traces, three new methods are proposed. The first method is named as sub-interval perturbed method, it is used for calculating the binary interval of the reconstructed result in an accident with binary interval traces, and it can overcome the interval extension problem well. The second method is based on interval arithmetic and the first method, it is used for calculating the ternary interval of the accident reconstruction result in an accident with ternary interval traces, and the most probable value of the reconstructed result is a number. The basic idea of the third method is the same as that of the second method, it is used for calculating the ternary interval of the accident reconstruction result in an accident with mixed interval traces, and the most probable value of the reconstructed result is an interval. All methods are demonstrated and validated by numerical cases. The results show that all methods are feasible and practical. Finally, a true vehicle-motorcycle accident is given, in which the braking distance of vehicle, and the throw distances of driver and motorcycle are all binary interval traces. The accident is reconstructed by the software PC-Crash, and the interval of impact velocity is analyzed. The interval of the velocity is [55.7, 64.3] km/h. This interval result is more objective than a single number.

Analysis of a special purpose vehicle’s behaviour after an edge drop-off onto a soft shoulder

The article concerns the dynamics of a four-axle 20 ton special purpose vehicle in the driver’s panicky defensive manoeuvre resulting from edge drop-off of wheels onto a soft shoulder. A calculation model in the PC-Crash software environment has been developed to include the complex mechanism of the soft soil response to the wheel movement. The analysis of the results indicates the danger manifested by strong wheels vibrations, instantaneous change of vehicle steerability characteristics and a high rate of increase of the yaw angle and vehicle pitch during braking with steered wheels turned. The calculations indicate an extremely adverse effect of the phase of vehicle oversteer which in the analysed motion of the vehicle lasts over 1.5 s. The calculations prove that in such a short time the driver has very little chance of any practical response to the non-typical behaviour of the vehicle which otherwise is, in general, understeered.

Simulation on the Vehicle Frontal Collision Based on the PC-Crash

The probability of frontal collision is the highest in the vehicle collision accidents, and crew injury mechanism of frontal collision is an attractive research subject. Based on the multi-rigid-body dynamics, a “vehicle-crew-belt” dynamics model is introduced, and software Pc-crash is used to simulate dynamic responses of this multi-rigid-body model by referencing basic parameters of FMVSS law. Dynamic response characteristics between the vehicle and the crew body are analyzed so as to expound the link between the vehicle movement and human-body injury. The result shows that a reliable evaluation of frontal collision is achieved, which provides a theory basic and practical reference for the research of accident injury.

Applicability Analysis for the Reconstruction Model of Automobile Two-Dimensional Eccentric Collision Accidents

In order to provide a theory algorithm for simulation and reconstruction analysis of automobile two-dimensional eccentric collision accidents, the applicability problems of the traditional dynamics model and trajectory model in this kind of accident were analyzed in theory respectively. Using PC-Crash software and the traditional models, a real accident case was reconstructed and analyzed. The comparative study between the reconstruction analysis results and the vehicles traces remained in the accident scene was conducted. According to the comparative study, reliabilities of the traditional models were verified.

Study of Correlation between Driver Emergency Measures and Pedestrian Injury Based on Combined Driving Simulator and Computer Simulation

Driving simulator and computer simulation are combined to reconstruct the kinematic process of pedestrian-vehicle crash. Firstly, in-depth data from 158 accident cases in Beijing is analyzed. Additionally, the typical accident factors, collision characteristics, road status, and drivers' emergency behavior are classified and integrated to establish virtual scenarios of pedestrian vehicle accidents. Moreover, volunteer drivers are tested on the driving simulator while data of vehicles' real-time kinetic parameters from different emergency measure stages is recorded. Furthermore, the process of pedestrian-vehicle crash is modeled and simulated by accident analysis software PC-CRASH to obtain the data of pedestrian's head centroid acceleration, and the HIC value is calculated as an injury indicator. Finally, the collected data is analyzed to find out the relation between drivers' various emergency measures and pedestrians' injury severity. The results show that steering with braking is the most effective measure among drivers' various measures. This paper may provide some valuable suggestions on research of driving safety as well as intelligent transportation.

Analysis and application of relationship between post-braking-distance and throw distance in vehicle–pedestrian accident reconstruction

Through theoretical analysis and introduction of some empirical parameters, the relationship between post-braking-distance and throw distance was studied concentratedly. Here, the post-braking-distance is the distance a vehicle will travel from the impact position to when it comes to a complete stop. Two useful formulas which are meaningful in vehicle-pedestrian accident reconstruction were finally obtained. The first one can be used to calculate impact speed according to throw distance, while the other one can describe the relationship between post-braking-distance and throw distance. Their feasibility has been validated by comparing with other scholars' empirical formulas and simulation results of software Pc-Crash, respectively. The relationship between post-braking-distance and throw distance has very bright application perspective in vehicle-pedestrian accident reconstruction such as helping policemen obtain more useful evidences, validating credibility of the throw distance, judging whether the vehicle is fully braked or not, determining the impact position etc. Finally its application was demonstrated by three cases, in which the impact speed was also calculated. All results until now have shown that conclusions obtained in this article are feasible and helpful in vehicle-pedestrian accident reconstruction.