Control and Application of Intelligent Restraint Systems

Conventional restraint systems designed to meet US FMVSS standards only have one level of operation. The seat belt imparts a restraint force to the occupant reflective of belt stiffness characteristics and the airbag is either inflated or not inflated. The system is tuned to one crash scenario, typically a 30 mph (48 kph) barrier crash with an unbelted 50^th%ile MHIII dummy. Situations involving other occupants, crash speeds or belt usage conditions may result in tradeoffs to maintain acceptable results for all conditions. Currently, there is considerable interest in adaptive restraint systems that can detect various crash conditions and adjust the restraint system to provide increased levels of protection. There is also a great deal of interest in systems that can detect an out of position occupant and adjust the airbag deployment to lessen the possibility of deployment induced injuries.

The development of restraint hardware has been on-going for some time and testing shows that these devices can provide enhanced occupant protection. The next logical step is to begin to combine these components with appropriate sensing technologies and control systems that understand the implications of the decision making process. The value of the adaptive restraint system has been demonstrated in its ability to adjust for different crash conditions and a degree of realtime decision making capability has been demonstrated in sled testing. Furthermore, significant reduction in airbag deployment induced injuries are made possible by detecting an out of position occupant and altering airbag inflation parameters.