Knee airbag apparatus for autonomous vehicle and method of controlling the same

1. A knee airbag apparatus for an autonomous vehicle, comprising:

an inflator operated by an airbag controller to generate airbag gas;

a first cushion configured to deploy toward knees of a seated passenger by the airbag gas, and including a first vent hole formed on a first surface of the first cushion;

a second cushion disposed between the first surface of the first cushion and the seated passenger and directly connected to the first surface of the first cushion; and

a first active vent arranged on the first vent hole to close the first vent hole and configured to selectively open the first vent hole,

wherein:

when the first cushion is deployed and the first active vent closes the first vent hole, only the first cushion is deployed, and

when the first cushion is deployed and the first active vent opens the first vent hole, the second cushion is deployed such that the first cushion and the second cushion are deployed with a time difference toward the knees of the seated passenger.

2. The knee airbag apparatus according to claim 1 , further comprising:

a third cushion connected to the first cushion and configured to fluidly communicate with the first cushion through a second vent hole formed on a second surface of the first cushion; and

a second active vent arranged on the second vent hole to close the second vent hole and configured to selectively open the second vent hole,

wherein:

when the first cushion is deployed and the second active vent closes the second vent hole, the third cushion is not deployed, and

when the first cushion is deployed and the second active vent opens the second vent hole, the third cushion is deployed.

3. The knee airbag apparatus according to claim 2 , wherein the third cushion is deployed below the first cushion to protect feet and shins of the seated passenger.

4. The knee airbag apparatus according to claim 2 , wherein the airbag controller is configured to receive signals from a collision detection sensor, a passenger detection sensor and a seat positioning mechanism and to control operation of the inflator, the first active vent and the second active vent.

5. The knee airbag apparatus according to claim 1 , further comprising: an airbag controller configured to determine whether to open the first vent hole based on an occurrence of head-on collision, and a distance between the seated passenger and a crash pad of the autonomous vehicle.

6. The knee airbag apparatus according to claim 5 , wherein the airbag controller is further configured to determine whether to open the first vent hole based on an occurrence of offset collision or oblique collision.

7. The knee airbag apparatus according to claim 2 , further comprising: an airbag controller configured to determine whether to open the second vent hole based on a distance between the seated passenger and a crash pad of the autonomous vehicle, and an occurrence of offset collision or oblique collision.

8. The knee airbag apparatus according to claim 2 ,

wherein the inflator is fixed to a crash pad of a driver seat,

wherein the first cushion and the second cushion are deployed toward knees of a passenger seated on the driver seat, and

wherein the third cushion is deployed toward feet and shins of the passenger seated on the driver seat.

9. The knee airbag apparatus according to claim 2 ,

wherein the inflator is fixed to a glove box coupled to a crash pad of a passenger seat,

wherein the glove box protrudes inward by operation of a glove box lifter when the inflator inflates,

wherein the first cushion and the second cushion are deployed toward knees of a passenger seated on the passenger seat, and

wherein the third cushion is deployed toward feet and shins of the passenger seated on the passenger seat.