Bumper and Grille Airbags Concept for Enhanced Vehicle Compatibility in Side Impact: Phase II

Figures & data

Fig. 1 FE model for via sled simulation.

Fig. 2 External airbags interaction with vehicle structure and crash dummy.

Fig. 3 Flow chart for bumper airbag design parameters iterations.

Fig. 4 FE Model of the SUV-Type buck-to-passenger car side impact.

Fig. 5 Circular cylinder bumper airbag with/without tether (airbag center section).

Fig. 6 Elliptical cylinder bumper airbag with/without tether (airbag center section).

Fig. 7 Top view of the airbags with and without tether.

Fig. 8 Via sled side impact test set-up.

Fig. 9 Via sled side impact test set-up.

Table 1 Tether effect on normalized dummy responses

Bag Shape	Unit	Cylinder	Cylinder
Bag Size Diameter × Length	cm	37 × 122	37 × 122
Tether		Without Tether	With Tether
Vent Area	cm^−2	125	125
Initial Pressure	KPa	105	105
Vent Pressure	KPa	170	170
Peak Pressure	KPa	190	190
Peak Head Acc.		0.41	0.38
TTI		0.75	0.86
Pelvis Acc.		0.56	0.53
Bumper Top Height	cm	54	54

Table 2 Bumper airbag shape effect on normalized dummy responses

Bag Shape	Unit	Cylinder	Ellipse
Bag Size Diameter × Length	cm	37 × 122	37 × 122
Tether		Without Tether	With Tether
Vent Area	cm^−2	125	125
Initial Pressure	KPa	105	105
Vent Pressure	KPa	170	170
Peak Pressure	KPa	190	190
Peak Head Acc.		0.38	0.35
TTI		0.86	0.79
Pelvis Acc.		0.53	0.38
Bumper Top Height	cm	54	54

Table 3 Bumper height effect on normalized dummy responses

Bag Shape	Unit	Ellipse	Ellipse	Ellipse
Bag Size Diameter × Length	cm	37 × 122	37 × 122	37 × 122
Tether		With Tether	With Tether	With Tether
Vent Area	cm^−2	125	125	125
Initial Pressure	KPa	105	105	105
Vent Pressure	KPa	170	170	170
Peak Pressure	KPa	190	190	190
Peak Head Acc.		0.35	0.32	0.34
TTI		0.79	0.62	0.91
Pelvis Acc.		0.38	0.39	0.52
Bumper Top Height	cm	54	46	39

Table 4 Via sled test results and airbags characteristics

		Baseline	Basic Cylinder/Grille Bag	Chambered Cylinder/Grille Bag	Chambered Ellipse/Grille Bag
HIC 36		1	0.31	0.38	0.29
TTI		1	0.81	0.75	0.72
Pelvis		1	0.47	0.6	0.57
Bumper Bag
Initial Pressure	KPa	NA	105	105	105
Vent Pressure	KPa	NA	172	172	172
Vent Diameter	cm	NA	15	15	15
Grille Bag
Initial Pressure	KPa	NA	3.5	3.5	3.5

Fig. 10 Via sled side impact test with SUV-type buck equipped with external airbags.

Table 5 Door armrest velocity obtained from the Via sled tests

	Armrest	Armrest	Dummy Contact
	Velocity	Velocity	Time
	mph	m/s	Ms
Baseline	31	13.78	18
Basic Cylinder BAB	17	7.56	32
Chambered Cylinder BAB	17.5	7.78	40
Chambered Ellipse BAB	16	7.11	42

Table 6 Finite element results for reaction surface gauge optimization

		Base Run
Bag Shape	Unit	Ellipse	Ellipse	Ellipse
Bag Size (depth × height × length)	cm	64 × 37 × 122	64 × 37 × 122	64 × 37 × 122
Initial Pressure	KPa	105	105	105
Vent Pressure	KPa	150	150	150
Peak Pressure	KPa	170	170	170
Reaction Surface Thickness	cm	0.1	0.15	0.2
TTI		1	0.94	0.94
Pelvis Acc.		1	0.95	1.01

Fig. 11 External airbags finite element concept model with reaction surface.

Fig. 12 Simulation of external airbag finite element concept model with reaction.

Fig. 13 Bumper airbag reaction surface hardware and assembly.

Fig. 14 Prototype bumper airbag final shape mounted on an SUV.

Fig. 15 Pre-inflated chambered prototype bumper airbag concept with bulkheads.

Fig. 16 Target and bullet velocity-time histories from the Via sled tests.

Fig. 17 Lateral velocity time-history curves of the armrest in the target vehicle.

Fig. 18 Bumper and grille airbags deployment sequence in vehicle-to-vehicle test.

Fig. 19 Armrest velocity comparisons.

Fig. 20 Normalized dummy responses for target vehicle.