1. Comparison of OICA and Korea Synchronisation Processes
IWG-DPPS
Comparison of OICA and Korea Synchronisation Processes
for Dynamic Testing
Martin Harvey, September 2018

2. Background
For deployable systems that do not have a permanently deployed position or TRT>HIT, dynamic testing is required ensuring synchronisation of the head form launch device and system deployment to achieve the correct head impact time.
The following slides compare the OICA and Korea processes which are used to calculate the synchronisation delay for establishing the correct fire time of the deployable system.

3. OICA Synchronisation Process (HIT > TRT)
Launch to head contact (190ms)
Synchronisation delay ( = 114ms)
Time after sensing to HIT (91-15 = 76ms) T0 T2 T1
ST (15ms)
Deployment Time (60ms)
TRT
Pedestrian to Vehicle Event
Lab Test
HIT (91ms)
Korea Synchronisation Process Case 1 (HIT > TRT)
a = = -16
Synchronisation delay = 190 – ( )
= 190 – 76
= 114 ms

4. JLR (OICA) Synchronisation Process (HIT < TRT)
Pedestrian to Vehicle Event
ST (15ms)
Deployment Time (60ms)
TRT
HIT (50ms) T0 T2 T2
Lab Test
Launch to head contact (190ms)
Synchronisation delay ( = 155ms)
TAS to HIT (50-15 = 35ms) T1
Korea Synchronisation Process Case 1 (HIT < TRT)
a = = 25
Synchronisation delay = 190 – ( )
= 190 – 35
= 155 ms

5. Korea Synchronisation Process Case 2
JLR (OICA) Synchronisation Process (HIT > TRT) when launch to contact time less than TRT
Pedestrian to Vehicle Event
Pedestrian to Vehicle Event
ST (15ms)
Deployment Time (60ms)
HIT (91ms)
TRT T
Lab Test
Launch to head contact (65ms)
Fire signal to deployable device 11ms before rig launch (65-76)
Time after sensing to HIT (91-15 = 76ms)
Korea Synchronisation Process Case 2
a = = -16
Synchronisation delay = 60 – ( )
= 60 – 49
= 11ms

6. Conclusion
OICA and Korea synchronisation processes result in identical synchronisation delay times.
As the OICA process only uses sensor time in the calculations and not TRT, this method is more suitable for pedestrian airbags where it is difficult to measure TRT.