1. Information for the Flexible Pedestrian Legform Impactor (Flex-PLI)
Informal Document No. GRSP-36-2
(36th GRSP, 7-10 December 2004, agenda item A.1.)
Information for the Flexible Pedestrian Legform Impactor
(Flex-PLI)
Ministry of Land, Infrastructure and Transport Government of Japan
(J-MLIT)

2. Construction TRL-LFI Flex-PLI 2003
Biofidelity Evaluation
TRL-LFI
Flex-PLI 2003
Thigh
(RIGID)
Thigh
(FLEXIBLE)
Damper
Knee
Joint
(Steel Knee
Bending Plate)
Knee Joint*
(ligament restraint system)
Leg
(RIGID)
Leg
(FLEXIBLE)
Flex-PLI has higher biofidelic construction than the TRL-LFI

3. Over all lower extremity bending motion is observed.
Kinematics
Flex-PLI can simulate human lower extremity bending motion properly.
FE-Model of TRL-LFI
TRL-LFI
Knee bending only
Flex-PLI
Human FE-Model (THUMS)
JASIC 2003 Report
Over all lower extremity bending motion is observed.

4. Measurement System TRL-LFI Flex-PLI 2003
for Knee ligaments
injury assessment
(Angle, Disp.)
for Leg injury
assessment
(Acc.)
Knee Shearing
(displacement)
Knee Bending
(angle)
Leg 0
(acceleration)
TRL-LFI
Knee Joint
65 mm
Impact
PCL (elongation)
MCL (elongation)
ACL (elongation)
LCL (elongation)
Flex-PLI 2003
Leg 1 (strain)
Leg 2 (strain)
Leg 3(strain)
Leg 4(strain)
Leg 5 (strain)
Thigh 1 (strain)
Thigh 2 (strain)
Thigh 3 (strain)
Thigh 4 (strain)
Knee Joint
92 mm
172 mm
252 mm
332 mm
93 mm
173 mm
253 mm
333 mm
413 mm
Lateral and Medial Condyle (force)
Impact
for Knee ligaments
injury assessment
(Elongation)
for Leg Injury
assessment
(strain)
no measurement
(cannot detect injury)
Flex-PLI has higher injury assessment ability than the TRL-LFI

5. Discussion

6. Over all lower extremity bending motion is observed.
Biofidelity Issue
TRL-LFI has a high possibility to mislead the protection way for the pedestrian lower extremity, since it cannot simulate the human lower extremity motion properly.
TRL-LFI
Knee bending only
Flex-PLI
Over all lower extremity bending motion is observed.

7. Measurement System Issue
for Knee ligaments
injury assessment
(Angle, Disp.)
for Leg injury
assessment
(Acc.)
Knee Shearing
(displacement)
Knee Bending
(angle)
Leg 0
(acceleration)
TRL-LFI
Knee Joint
65 mm
Impact
TRL-LFI has a high possibility to mislead the protection way for the pedestrian lower extremity, since it doesn’t have a measurement system for the injury assessment of the lower part of the leg.
no measurement
(cannot detect injury)
TRL-LF cannot detect the lower part of the leg severity

8. Conclusions

9. Conclusions Flex-PLI has high biofidelity
higher injury assessment ability than the TRL-LFI
J-MLIT recommends to utilize the Flex-PLI as a tool for GTR/PS legform test.
However, because of the lack of experience in using the Flex-PLI as a certification tool, a further confirmation process is needed.

10. Thank you for your attention!