US Patent 7988190 Airbag deployment control using seatbelt-mounted sensor

Method and system for controlling inflation of an airbag in a vehicle which protects an occupant from injury in a crash involving the vehicle includes sensing a crash involving the vehicle for which deployment of the airbag is desired, inflating the airbag to protect the occupant in the crash involving the vehicle upon sensing of the crash, incorporating an accelerometer in a seatbelt worn by the occupant, and adjusting the continued inflation of the airbag after contact of the airbag with the occupant based on the acceleration sensed by the accelerometer. The accelerometer may be arranged to determine movement or acceleration of the seatbelt which can be correlated to contact between the airbag and the seatbelt, i.e., based on changes in the measured acceleration of the seatbelt arising from contact of the airbag with the seatbelt.