Analysis of Rear Seat Sled Tests with the 5th Female Hybrid III: Incorrect Conclusions in Bidez et al. SAE 2005-01-1708 2019-01-0618
Objective: Sled test video and data were independently analyzed to assess the validity of statements and conclusions reported in Bidez et al. SAE paper 2005-01-1708 .
Method: An independent review and analysis of the test data and video was conducted for 9 sled tests at 35 km/h (21.5 mph). The 5th female Hybrid III was lap-shoulder belted in the 2nd or 3rd row seat of a SUV buck. For one series, the angle was varied from 0, 15, 30, 45 and 60 deg PDOF. The second series involved shoulder belt pretensioning and other belt modifications.
Results: Bidez et al.  claimed “The lap belts moved up and over the pelvis of the small female dummy for all impact angles tested.” We found that there was no submarining in any of the tests with the production lap-shoulder belts. Bidez et al.  claimed “H3-5F dummies began to roll out of their shoulder belt at… 30 degrees. Complete loss of torso support was seen at 45 degrees without significant kinetic energy dissipation.” We found that the shoulder belt remained in place and restrained the upper torso in the 0, 15 and 30 deg sled tests. At 45 and 60 deg, significant restraint was provided before the belt slipped off the shoulder. It remained in contact with the arm and chest providing restraint. Bidez et al.  claimed “The results indicated kinematic movement of the dummies, which were predictive of injury in all sled runs.” We found that the kinematic control was good and the biomechanical responses were well below IARVs for the 5th female Hybrid III. Bidez et al.  claimed “a retractor pretensioner (7 ms fire time) eliminated both submarining and torso rollout in the H3-5F in the conditions tested.” We found that the pretensioner firing pulled the lap belt up onto the abdomen inducing submarining and causing abdominal loading in two out of four tests.
Conclusion: The independent review of the videos and data shows that Bidez et al.  misstated the results, misrepresented the findings and reached incorrect conclusions on the testing.