Transcript Head Restraint IWG Document: HR-1-7 GRSP-Informal Head Restraints GTR OICA presentation 1 February 2005 ABSTRACT from ACEA Whiplash Test Series on Repeatability and Reproducibility of Proposed Test.

Head Restraint IWG Document: HR-1-7
GRSP-Informal Head Restraints GTR
OICA presentation
1 February 2005
ABSTRACT from
ACEA Whiplash Test Series on
Repeatability and Reproducibility of
Proposed Test Procedures
September 2004
Céline Adalian & Raimondo Sferco
Purpose of the ACEA Study

Test series conducted in two phases
 Phase 1: Repeatability testing
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
3 different seats used
3 repeat tests of each seat
All repeat testing conducted at Thatcham
Phase 2: Reproducibility testing



3 different seats used
Testing conducted in five different labs (using the same test
protocol)
One test per configuration
2
HRMD Setup used

Initial Geometric
assessment with HRMD

Seat = mid height / mid
rails

HR = mid position if
locked or else fully
down
Sample picture of HRMD measurement
3
Parameters investigated with respect to
test set-up


Initial position of seat
 Seat back angle
 Head restraint stem angle
Initial position of SAE Manikin + HRMD
 H point
 Backset and head restraint height
4
Seat setup as results of HRMD measurements
Seat back and stem angle
Seat back configuration
22
20
18
Stem angle (°)
16
14
12
dispersion Saab 9-3
Saab 9-3
dispersion Skoda Fabia
Skoda Fabia
dispersion BMW 3er
BMW 3er
10
8
6
24
24.2
24.4
24.6
24.8
25
25.2
25.4
25.6
25.8
26
torso angle (°)
Points marked with a “+” are from the tests made at Thatcham (repeatability assessment)
5
HRMD setup
HRMD H-point measurement result scatter
H-point distance measured on Oscar+HRMD
100
90
dispersion Saab 9-3
Saab 9-3
dispersion Skoda Fabia
Skoda Fabia
dispersion BMW 3er
BMW 3er
Z H-point (mm)
80
70
60
50
40
100
120
140
160
180
200
220
240
X H-point (mm)
Points marked with a “+” are from the tests made at Thatcham (repeatability assessment)
6
HRMD setup
HRMD height and backset measurement result scatter
Head to head restraint distance measured with HRMD
40
50
Height (mm)
60
70
80
90
scatter Saab 9-3
Saab 9-3
scatter Skoda Fabia
Skoda Fabia
scatter BMW 3er
BMW 3er
100
10
20
30
40
50
60
70
80
90
100
110
120
Backset (mm)
Points marked with a “+” are from the tests made at Thatcham (repeatability assessment)
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HRMD torso angle vs backset measurement result scatter
Torso angle vs. backset with HRMD
26
Saab 9.3
25.8
Skoda Fabia
25.6
torso angle [°]
BMW 3 series
25.4
25.2
25
24.8
24.6
24.4
24.2
0
10
20
30
40
50
60
70
80
90
100
backset [mm]
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Conclusions on HRMD measurements
and set-up procedure

Analysis shows that reproducibility and repeatability
issues still exists.

The use of the HRMD procedure by the different labs
caused seat back angle (stem angle) differences of up
to 4 deg. This could be seen as significant. One
degree change in the stem angle will lead in theory to
15 mm increase in backset.

In the practical measurement the maximum
differences of backset and height for reproducibility
were more than 20 mm.
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