The proliferation of vehicle occupant restraint systems in recent years has saved many lives when unfortunate vehicle accidents occur.  Various vehicle occupant restraint systems are utilized and typical inflatable restraint systems include driver and passenger front airbags, side airbags and side curtain airbags.  Non-inflatable restraint systems also exist, and a pretensioner seatbelt system that tightens seatbelts is a sample non-inflatable restraint system.  These various occupant restraint systems are all critical in protecting vehicle occupants during accidents, but are only as good as the deployment control systems tasked with detecting and deploying occupant restraint systems. 
Typically, deployment control systems utilize certain signals from sensors placed throughout an automobile to determine if certain predetermined thresholds are satisfied when deploying an occupant restraint system.  Automobile engineers, scientists, and other researchers usually obtain these predetermined thresholds by analyzing test data obtained from simulated crash and rollover events.  Once obtained, the predetermined thresholds are programmed into deployment control systems.  And, the programmed detection and deployment control systems determine whether or not to initiate occupant restraint systems based on incoming sensor data.  Although current detection and deployment systems protect many vehicle occupants, such systems do not periodically update the deployment thresholds with real-time data nor do these systems utilize multi-staged rollover sensing systems.  Additionally, current detection and deployment systems may inadvertently initiate occupant restraint systems which may harm vehicle occupants, alarm vehicle occupants resulting in an automobile accident, and may cost vehicle owners large sums of money to repackage occupant restraint systems.  Current deployment systems may also inadvertently deploy rollover restraint systems instead of crash restraint systems during a rollover or deploy crash restraint systems during a rollover event. 
What is needed, therefore, is a rollover detection and deployment control system capable of updating rollover event thresholds with real-time data enabling occupant restraint systems to deploy based on changing vehicle characteristics.  What is also needed is a deployment control system to distinguish between crash, rollover, and safe events to prevent the misfiring of crash and rollover occupant restraint systems.  An intelligent multi-stage rollover sensing system would prevent costly deployment system misfires and increase rollover event detection accuracy.