Dual depth airbag with active venting

An airbag assembly, comprising:

• a release device configured to communicate electronically with a sensor;
• and,
• an inflatable airbag cushion configured to be deployed to a first configuration and a second configuration, wherein the second configuration has a greater volume than the first configuration, the inflatable airbag cushion comprising:
• a cushion membrane which defines an interior of the inflatable airbag cushion;
• at least one airbag depth restraining tether attached to a face-proximal surface of the cushion membrane and extending to, and being releasably coupled to the release device, such that upon deployment of the airbag to the first configuration, the airbag depth restraining tether is not released, and the airbag depth restraining tether limits the depth of inflatable airbag cushion deployment, and wherein deployment to the second configuration is achieved by the release device releasing the airbag depth restraining tether such that the airbag depth restraining tether does not limit the depth of inflatable airbag cushion deployment;
• wherein the at least one airbag depth restraining tether comprises
• at least one intermediate portion comprising an elongated piece of material, the intermediate portion having an end portion which may be coupled to a release device when the airbag assembly is in an undeployed configuration or is deployed to a first configuration;
• and,
• at least two distal portions comprising pieces of material, wherein the distal portions are attached to the intermediate portion and extend to and are attached to the face-surface of the cushion membrane, the two distal portions bilaterally symmetrically disposed on the face-surface on opposite sides of a vertically oriented mid-line of the deployed cushion membrane;
• at least one airbag height restraining tether releasably coupled to the release device, the airbag height restraining tether extending to, and attached to a lap-proximal surface of the inflatable airbag cushion membrane such that upon deployment of the airbag to the first configuration, the airbag height restraining tether is not released, and the airbag height restraining tether limits the height of the inflatable airbag cushion, the airbag height restraining tether being released for deployment of the airbag to the second configuration such that airbag height restraining tether no longer limits the height of inflatable airbag cushion deployment, allowing the lap-proximal surface of the airbag to expand in a direction of an occupant's lap, the airbag height restraining tether coupled to the at least one airbag depth restraining tether such that after release from the release device, the airbag height restraining tether and airbag depth restraining tethers remain coupled;
• at least one closeable vent disposed on the cushion membrane and configured to vent gas out of the interior of the inflatable airbag cushion, wherein the closeable vent is configured to change from an open state during initial airbag deployment and deployment to the first configuration, to an at least partially closed state upon airbag deployment to the second configuration;
• and,
• at least one closeable vent strap coupled to the closeable vent and extending to and coupled to the at least one airbag depth restraining tether, the closeable vent strap being of such a length that upon deployment of the airbag to the first configuration, the closeable vent strap is sufficiently slack that the closeable vent is not closed, and upon deployment of the airbag to the second configuration, the closeable vent strap is placed under tension by the expansion of the lap-proximal surface of the cushion membrane sufficient to at least partially close the closeable vent.