JAMA Stance on Compatibility Test Method

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JAMA Stance on Compatibility Test Method
Hideki Koga Sub-Chairman Frontal Impact Working
Group
November 2007
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1. Short-term Strategies
(1) Views in Japan on the compatibility issue
A new regulation reflecting comments from the
Council for Transport of MLIT will be established
in the near future.
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Regulation (Phase 1)
Japan
Assessment
JAMAs position on compatibility
Arrangement of side members is important.
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Matching the geometry of the frame is most
important.
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(2) Test/assessment methods
The following three proposals are currently under
discussion with MLIT

• (A) Alignment of geometry (equivalent to US TWG
  voluntary regulation)
  
• Front side members must geometrically be within
  the Part 581 zone.
  
• Alternatively, SEAS must be employed.
• (JAMAs proposal 1)
• (B) Assessment with forces using multiple load
  cell barrier
  
• A standard will be set for the force applied on
  rows 3 and 4.
  
• (JAMAs proposal 2)
• (C) Assessment with AHOF
• AHOF must be within the Part 581 zone.
• Alternatively, SEAS must be employed.
• (Under NHTSA Research , which JAMA opposes)

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(A) Alignment of geometry (equivalent to US TWG
voluntary reg.)
? Matching the geometry of the frame is most
important.
Direct geometrical measurements shall be taken.
Front side members must be within the Part 581
zone otherwise, SEAS having a certain strength
must be provided.
? Tasks
To develop a standard than can properly assess
any frame.
e.g. Which height should be measured?
Valid standard is necessary currently under
consideration.
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SUVs trucks are covered in US regulation.
In Japan, supermini cars are also included
More complex than trucks
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(B) Assessment with forces using multiple load
cell barrier
? Method of measuring the height of side members
is being developed.
Set target loads for rows 3 and 4.
? Tasks
To ensure accurate detection of the position of
the frame irrespective of the influence of the
engine or auxiliary machines.
Rigid wall
Loads of this part are specified.
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Assessment is conducted by frontal collision with
FWRB and AHOF obtained. AHOF400 must be within
the Part 581 zone. Alternatively, SEAS must be
employed.
(C) Assessment with AHOF
? Under NHTSA Research
Upper end
Lower end of side MBR
380
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? Reasons for JAMAs opposition
AHOF
1. Some AHOF values can clearly deviate from the
frame position.
Vehicle A
Vehicle B
2. The correlation between AHOF and actual
accident conditions seems weak (AM values).
Aggressivity Metric
Driver Fatalities in collision partner

(Number of Crashes of subject vehicle)/1000
3. The validity of AHOF has not been globally
proved. MLITs assessment may be inappropriate in
the long term.
Correlation coefficient AM vs AHOF
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2. Long-term Strategies (consideration of future
test/assessment methods)
Test/assessment methods are considered taking
into account stiffness matching in addition to
geometric matching.
KW400
MDB
PDB
PDB
Honeycomb
Barrier force
Inclination
Amount of car crush
400mm
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3. Summary
(1) Short-term strategies
- Arrangement of side members is important
- For proper assessment of the above, the
following 3 proposals are being discussed
(A) Alignment of geometry (equivalent to US TWG
voluntary regulation) (B) Assessment with forces
using multiple load cell barrier
(C) Assessment with AHOF
(2) Long-term strategies
Since matching of both geometry and stiffness is
important, test/assessment methods which can
check the matching properly will be developed.
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Thank you.