Patent attributes
An occupant protection system has a component in question reduced in size and cost. The occupant protection system includes: a rollover airbag device provided in a vehicle interior; a battery configured to supply power to the rollover airbag device; a controller configured to determine a rollover of a vehicle and, if a rollover of the vehicle is determined, activate the rollover airbag device using power supplied from the battery; and a backup power source configured to charge power to be used if the battery fails. The controller determines a collision of the vehicle and examines the battery for any failure and, if a collision of the vehicle is determined and the battery is examined to have a failure, activates the rollover airbag device using the power charged in the backup power source.