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Assessment of the effectiveness of Intersection Assistance Systems at urban and rural accident sites
(2015)
An Intersection Collision Avoidance System is a promising safety system for accident avoidance or injury mitigation at junctions. However, there is still a lack of evidence of the effectiveness, due to the missing real accident data concerning Advanced Driver Assistance Systems. The objective of this study is the assessment of the effectiveness of an Intersection Collision Avoidance System based on real accidents. The method used is called virtual pre-crash simulation. Accidents at junctions were reconstructed by using the numerical simulation software PC-Crashâ„¢. This first simulation is called the baseline simulation. In a second step the vehicles of these accidents were equipped with an Intersection Collision Avoidance System and simulated again. The second simulation is called the system simulation. In the system simulation two different sensors and four different intervention strategies were used, based on a time-to-collision approach. The effectiveness of Intersection Collision Avoidance System has been evaluated by using an assessment function. On average 9% of the reviewed junction accidents could have been avoided within the system simulations. The other simulation results clearly showed a change in the principal direction of force, delta-v and reduction of the injury severity.
Test and assessment procedures for passive pedestrian protection based on developments by the European Enhanced Vehicle-safety Committee (EEVC) have been introduced in world-wide regulations and consumer test programmes, with considerable harmonization between these programmes. Nevertheless, latest accident investigations reveal a stagnation of pedestrian fatality numbers on European roads running the risk of not meeting the European Union- goal of halving the number of road fatalities by the year 2020. The branch of external road user safety within the EC-funded research project SENIORS under the HORIZON 2020 framework programme focuses on investigating the benefit of modifications to pedestrian test and assessment procedures and their impactors for vulnerable road users with focus on the elderly. Injury patterns of pedestrians and cyclists derived from the German In-Depth Accident Study (GIDAS) show a trend of AIS 2+ and AIS 3+ injuries getting more relevant for the thorax region in crashes with newer cars (Wisch et al., 2017), while maintaining the relevance for head and lower extremities. Several crash databases from Europe such as GIDAS and the Swedish Traffic Accident Data Acquisition (STRADA) also show that head, thorax and lower extremities are the key affected body regions not only for the average population but in particular for the elderly. Therefore, the SENIORS project is focusing on an improvement of currently available impactors and procedures in terms of biofidelity and injury assessment ability towards a better protection of the affected body regions, incorporating previous results from FP 6 project APROSYS and subsequent studies carried out by BASt. The paper describes the overall methodology to develop revised FE impactor models. Matched human body model and impactor simulations against generic test rigs provide transfer functions that will be used for the derivation of impactor criteria from human injury risk functions for the affected body regions. In a later step, the refined impactors will be validated by simulations against actual vehicle front-ends. Prototyping and adaptation of test and assessment procedures as well as an impact assessment will conclude the work of the project at the final stage. The work will contribute to an improved protection of vulnerable road users focusing on the elderly. The use of advanced human body models to develop applicable assessment criteria for the revised impactors is intended to cope with the paucity of actual biomechanical data focusing on elderly pedestrians. In order to achieve optimized results in the future, the improved test methods need to be implemented within an integrated approach, combining active with passive safety measures. In order to address the developments in road accidents and injury patterns of vulnerable road users, established test and assessment procedures need to be continuously verified and, where needed, to be revised. The demographic change as well as changes in the vehicle fleet, leading to a variation of accident scenarios, injury frequencies and injury patterns of vulnerable road users are addressed by the work provided by the SENIORS project, introducing updated impactors for pedestrian test and assessment procedures.
The bicyclist accidents were analyzed to get better understanding of the occurrences and frequency of the accidents, injury distributions, as well as correlation of injury severity/outcomes with engineering and human factors in two different countries of China and Germany. The accident cases that occurred from 2001 to 2006 were collected from IVAC database in Changsha and GIDAS database in Hannover. Based on specified sampling criteria, 1,570 bicyclist cases were selected from IVAC database in Changsha, and 1806 cases were collected from Hannover, documented in GIDAS database. Statistical analyses were carried out by using these selected data. The results from the statistical analysis are presented and discussed in this study.
For the estimation of the benefit and effect of innovative Driver Assistance Systems (DAS) on the collision positions and by association on the accident severity, together with the economic benefit, it becomes necessary to simulate and evaluate a variety of virtual accidents with different start values (e.g. initial speed). Taken into account the effort necessary for a manual reconstruction, only an automated crash computation can be considered for this task. This paper explains the development of an automated crash computation based on GIDAS. The focus will be on the design of the virtual vehicle models, the method of the crash computation as well as exemplary applications of the automated crash computation. For the first time an automated crash computation of passenger car accidents has been realized. Using the automated crash computation different tasks within the field of vehicle safety can be elaborated. This includes, for example, the calculation of specific accident parameters (such as EES or delta-V) for various accident constellations and the estimation of the economic benefit of DAS using IRFs (Injury Risk Functions).
Ein selbstverständliches Mittel zur Senkung von nächtlichen Verkehrsunfällen ist die ortsfeste Straßenbeleuchtung. Bei Einsparbestrebungen in den öffentlichen Haushalten wird oft versucht, das Niveau der Straßenbeleuchtung herunterzuschrauben. In einem Forschungsvorhaben sollte deshalb untersucht werden, wie sich Beleuchtungsänderungen auf das Unfallgeschehen auswirken. Das Vorhaben war als Vorher-/Nachher-Studie angelegt, die in 6 deutschen Städten auf je 10 Untersuchungs- und Kontrollstrecken stattfand. Auf den Untersuchungsstrecken wurde die Beleuchtung zu einem bestimmten Zeitpunkt verändert, auf den Kontrollstrecken unterblieb diese Veränderung. Ergebnis der Studie ist, dass die Unfälle besonders in der verkehrsschwachen Zeit von 23 bis 5 Uhr zurückgingen. Die Anzahl aller Unfälle ging um (nicht signifikante) 28 Prozent, die der Fußgänger- und Radfahrerunfälle um (signifikante) 68 Prozent zurück. Auch die Zahl der Verletzten sank um (nicht signifikante) 45 Prozent. Diese Ergebnisse bestätigen tendenziell die Resultate vieler anderer Studien, dass Abschalten oder selbst Reduzierung der Straßenbeleuchtung das Unfallrisiko erhöht. Das gilt gerade auch für die verkehrsschwachen Nachtstunden.
Aim of the study was to evaluate the protective effect of bicycle helmets particularly considering injuries to the head and to the face. Accidents with the participation of bicyclists which occurred from 2000 to 2007 were chosen from GIDAS. We observed that injuries to the head and face were more severe in the group of non-helmeted riders. There seems to be no significant difference in injuries with AIS 3-6. Altogether 26 cyclists were killed. 2 of them wore a helmet (1% of helmeted cyclists), 24 did not (1% of non-helmeted cyclists). Only one killed rider (without helmet) did not suffer from polytrauma (only head injuries recorded). The findings seem to support the thesis of a preventive effect of the bicycle helmet, however the two groups are different in their characteristics related to riding speed. Necessarily we need a multivariate model to evaluate the effect of helmets.
Die Zielsetzung der Arbeit bestand darin, Erkenntnisse über das "Dunkelfeld" beziehungsweise die "Unfalldunkelziffer" der amtlichen Straßenverkehrsunfallstatistik in Deutschland zu gewinnen. Dazu wurde eine Datenerhebung in einem begrenzten Gebiet durchgeführt. Die Untersuchung sollte Hinweise ermöglichen über die Größe der Unfalldunkelziffer in Abhängigkeit von bestimmten Unfallmerkmalen sowie über die Struktur des Dunkelfeldes im Vergleich zur amtlichen Statistik. Als unterer Grenzwert für die Unfalldunkelziffer in der Pilotstudie wird ein Wert von 44 % angesehen. Die Untersuchung zeigt eine deutliche Abhängigkeit der Dunkelziffer von der Unfallschwere. Die Dunkelziffer liegt geringer bei Unfällen mit "ungeschützten" Unfallobjekten (Unfälle mit Fußgängern und Zweiradfahrern). Der Erfassungsgrad für Nachtunfälle ist größer als für Tagunfälle. Die Untersuchungsergebnisse zeigen insgesamt, dass die Struktur der amtlichen Statistik deutlich von der Struktur des Dunkelfeldes abweicht. Es wird die begründete Annahme ausgesprochen, dass die amtliche Verkehrsunfallstatistik unvollständig ist, wobei der Erfassungsgrad nicht einheitlich ist, sondern von verschiedenen Merkmalen (Unfallschwere, Unfallart, etc.) abhängt.
Real world accident reconstruction with the Total Human Model for Safety (THUMS) in Pam-Crash
(2013)
Further improvement of vehicle safety needs detailed analysis of real world accidents. According to GIDAS (German In-Depth Accident Study) most car to car front accidents occur at mid-crash severity. In this range thoracic injuries already occur. In this study a real world frontal crash with mid-crash severity out of the AARU database was reconstructed. The selected car to car accident was reconstructed by AARU by means of pc-crash software in order to get the initial dynamic accident conditions. These initial conditions were used to reconstruct the complete accident in more detail using FE models for the car structure and the occupants. Occupant simulations were performed with FE HIII-dummy models and the THUMS using Pam-Crash code. An initial THUMS validation was performed in order to verify the model-´s biofidelity by means of table-top test simulations. THUMS bone stiffness values were modified to match the real word occupant age. A comparison between driver and passenger restraint system loading was done, as well as an injury prediction comparison between the HIII-dummy model and THUMS response for both cases. Detailed comparison between the HIII-dummy models and THUMS regarding thoracic loading are discussed.
To date, the Trauma Registry (TraumaRegister DGU-® contains data of approximately 100.000 severely injured patients, 65% of which suffered from a road traffic crash. Thus, it is the world's largest data base for severely injured patients. The article describes the development of the registry and explains how it was rolled out over Germany using the established structure of the German Trauma Network (TraumaNetzwerk DGU-®). In addition, this article presents three typical use cases from the fields of quality management, policy making and system-wide interventions, clinical research and injury prevention. In conclusion, the TraumaRegister DGU-® is a well-established tool for various purposes related to the control and reduction of the burden of road injury. Its ongoing expansion to other countries will support the goal of international benchmarking of hospitals and trauma systems.
It is very important for Automotive OEMs to get feedback on their product performance on real roads for continuous improvement. Every OEM has a way of collecting this feedback for various performance parameters. Systematic accident research is a way to generate the information related to safety performance of the vehicle. In India, while there is a large amount of data related to the accidents, it is found this data is aimed at understanding the gross statistics and not directly useful for technology development. This paper explains learnings from a pilot study carried out in collaboration with an Emergency Medical Services provider on one of the expressways (motorways). This pilot study has resulted in development of working model that could now be scaled up at for wider application. The paper also presents some of the important observations based on the data collected.