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Chalmers University of Technology
Summary of Swedish
Research Using CrashRecorder Data
Robert Thomson & Helen Fagerlind
Crash Safety Division
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Chalmers University of Technology
Chalmers Crash Safety Division
Injury Biomechanics Research Primary focus on:
neck injuries
head injuries
pedestrian safety
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Chalmers University of Technology
Research Tools
Mechanical Testing Including development of crash test
dummies
BioRID: Biofidelic Rear Impact Dummy Computer Simulation
MADYMO
RADIOSS LS-Dyna
Accident Investigation / Reconstruction
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Chalmers University of Technology
Crash SeverityFolksam CPR Data
0
5
10
15
20
25
0
0 0.05 0.1 0.15 0.2 0.25 0.3
5
1015
20
25
30
Veloc
ity[m/s]
V
Acceler
ation[g]
Time [s]
0
10000+
0 0.05 0.1 0.15 0.2 0.25 0.3
0
5
10
15
20
25
30
V
Acceleration[g]
Velocity[m/s]
Conventional Reconstruction Methods
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Chalmers University of Technology
Crash Recorder / EDR
Opportunity to look inside the crashevent
Remove one level of uncertainty in
collision analysis
Allows injury causes and injury
mechanisms to be better understood
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Chalmers University of Technology
Crash Recorder Systems in Sweden
Volvo Cars Digital Accident Research Recorder
(DARR)
Saab Automobile AB
Crash Memory
Folksam Research Crash Pulse Recorder (CPR)
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Chalmers University of Technology
DARR
Volvo Cars airbag sensor uses a piezo-electric accelerometer
A recording function during the impact
phase was added to the sensor in 1994
Only Volvo Cars has access to the
recorded data
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Chalmers University of Technology
DARR Data Processing
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Chalmers University of Technology
Crash Memory
Saab Automobile AB collects crashpulses in Sweden for internal research
purposes
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Chalmers University of Technology
Crash Pulse Recorder (CPR)
Folksam Research developed the CPR
Since 1992, 160 000 cars have been
equipped in Sweden
Previous vehicles fitted with a CPRinclude Honda, Opel etc., currently
installed in most new Toyota vehicles
registered in Sweden
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Chalmers University of Technology
Crash Pulse Recorder (CPR)
Innovative crash event recorder Motion of a spring-mass mechanism
saved on photographic film 3 g activation threshold
1000 Hz recording rate
Film is processed after unit is removedfrom vehicle
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Chalmers University of Technology
Crash Pulse Recorder (CPR)
Accident data presented by Folksamresearchers
Cooperation with:
Chalmers
Autoliv Research
Swedish National Road Administration
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Chalmers University of Technology
CPR Data Applications
Grouping injury data with reliablecollision severity parameters
Analysis of crash pulse components
Peak and average acceleration
Pulse shape characteristics
V,
V33,
V66,
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Chalmers University of Technology
CPR Analyses
Pulse shape characteristics
to investigate injury thresholds
injury mechanisms
0
0.2
0.4
0.6
0.8
1
0 5 10 15 20 25 30
Peak Acceleration [g]
Risk
Injury Risk Curves
(Based on reliablecrash severity estimates)
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Chalmers University of Technology
CPR Recorded Pulse Shapes
Time [s]
0
20
40
60
0 50 100 150
Acceleration[m/s/s]
Two pulses with the same V
Long term neck injury
No long term injury
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Chalmers University of Technology
Comparison of Occupant Responses
Long term neck injury No long term injury
Simulation based on crash pulses shown in previous slide
Results in:
The effect of crash pulse shape on AIS1 neck injuries in frontal impacts
Kullgren A, Thomson R, Krafft M1999 IRCOBI Conference, Barcelona, Spain
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Chalmers University of Technology
CPR Applications
Reconstruction of occupant kinematics usingadvanced occupant simulation codes with
crash pulse data as input
Currently used in developing an injurycriterion for neck injuries
Take advantage of the non-volunteer test
subjects Can provide data not available from
biomechanical testing based on human volunteers
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Chalmers University of Technology
Potential Applications of DetailedCrash Data in Sweden
Pre-crash data to investigate collisioncausation
Evaluation of active safety systems
Continued accident reconstruction of
occupant kinematics
National and European Union researchactivities
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Chalmers University of Technology
Potential for EDR Standardisation
Opportunity to focus research activitiesaway from guesswork of injury severity
measures and focus on injury
biomechanics
Better product performance
Better rulemaking Safer roads!
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Chalmers University of Technology
Contact Information
Robert Thomson +46 31 772 3645
Helen Fagerlind
+46 31 773 3613
