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Crash recorders – opening up the box

Anders Kullgren

Head of road traffic safety research at Folksam

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Delta-V 52.1 km/hMean acc 12.6 gPeak acc 31.7 g

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• Why crash recorders?

• Potential applications

• Different types of recorders / running crash

recorder projects

• Examples of results

• Summary

Crash recorders - content

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Benefits of using crash recorders• Increased quality of accident data

– Increased accuracy of data– Possibility to use information previously not possible to obtain

• Better evaluation of new safety technology

• Knowledge of injury thresholds for the design of a crashworthy road transport system

• Better understanding of injury causes and injury mechanisms

• Influence on accident involvement risk?

• Useful from legal aspects (insurance)

• Information used for ”e-Call”systems

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Some applications• Pre-crash data to investigate collision causation

– Evaluation of active safety systems

• Crash data to investigate crashworthiness– Evaluation of interior safety systems

– Calculate injury risk versus impact severity

• Accident reconstruction minor injuries AIS1+ (n=278)moderate injuries AIS2+ (n=72)serious injuries AIS3+ (n=18)

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Furhter applications• Linking laboratory to real-life

crashes

– Reconstruction of occupant kinematics using advanced occupant simulation codes with real-life data, such as crash pulse and car characteristics, as input

– Calculate injury risk functions and injury tolerance levels

– Validation of injury criteria

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Types of crash recorders

• Purpose of the recorder – Research

– Legal aspects and accident involvement

• Pre crash, crash and post crash data

• Type of parameters recorded– Performance of the car

– Crash severity

– Driver behaviour

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Examples of running “large fleet” projects• Since 1990s - GM and Ford cars (more advanced in late

90s)

• Since 1995 - Volvo DARR in Volvo cars – approx 500.000

cars fitted

• Other manufacturers, Saab etc…

• Since 1992 - Folksam CPR project - 220.000 cars fitted

with Crash Pulse Recorders

• Since 1995 - UDS in Austria, Switzerland and Germany…

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Storage and availability of data

• Important that such data can be available for

research purposes

• Important for designers of both road infra-

structure and cars

• Who will have access to the data?

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Some examples of results from the Folksam crash recorder database

• Example of crash

• Exposure data

• Injury risk

• Evaluation of safety technology (airbag)

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Toyota Yaris – Saab 900 (old)

Minor injuries (clav. fracture)

Driver + front seat pass.fatally injured

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acceleration (g)change of velocity (km/h)

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Delta-V 52.1 km/hMean acc 12.6 gPeak acc 31.7 g

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Number of crashes and injured - Delta-V

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No injury (n=174)AIS1 (n=206)AIS2 (n=54)AIS3+ (n=18)

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inju

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Delta-V (km/h) n=452

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AIS1+ (n=278)AIS2+ (n=72)AIS3+ (n=18)

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Delta-V (km/h) n=452

Injury risk - Delta-V

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Influence of airbags on risk of whiplash injury in frontal impacts (1999 figures)

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Cars with airbags (n=88)

Cars without airbags (n=36)

Airbag deployment (n=88)

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peak acceleration (g)

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Summary

• Crash recorders are important

– for evaluation of new safety technology

– to get knowledge of injury thresholds for the

design of a crashworthy road transport system

• Important to encourage initiatives where

data can be available for research

institutes and governmental bodies

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Wider use

• A wider use of crash recorders or event data recorders is desirable. A mandatory fitment of such devices would help but is not necessary.

• It is important to ensure that data from recorders will be collected and stored in such a way that it is available to designers of both cars and road-side objects, and especially to the responsible bodies for the road transport system.