Method and apparatus for controlling an actuatable protection device with off-road and rollover detection

A method for controlling actuation of an actuatable restraint in response to a vehicle rollover event, comprising:

• detecting whether the vehicle is being driven on-road or being driven off-road by evaluating a vehicle roll angle (R_ANGLE) over time, wherein the vehicle is detected as being driven off-road in a case where the vehicle roll angle crosses both an upper roll threshold indicative of positive roll angle and a lower roll threshold indicative of negative roll angle without the rollover discrimination metric entering a reset box;
• determining whether the vehicle is undergoing a roll event that would warrant actuation of the actuatable restraint if the vehicle was being driven on-road;
• and
• actuating the actuatable restraint in response to determining that a roll acceleration (D_RATE) of the vehicle indicates that the roll event is continuing.

A vehicle safety system comprising:

• an actuatable restraint;
• a controller configured to control actuation of the actuatable restraint by:
• detecting whether the vehicle is being driven on-road or being driven off-road by evaluating a vehicle roll angle (R_ANGLE) over time, wherein the vehicle is detected as being driven off-road in a case where the vehicle roll angle crosses both an upper roll threshold indicative of positive roll angle and a lower roll threshold indicative of negative roll angle without the rollover discrimination metric entering a reset box;
• determining whether the vehicle is undergoing a roll event that would warrant actuation of the actuatable restraint if the vehicle was being driven on-road;
• and
• actuating the actuatable restraint in response to determining that a roll acceleration (D_RATE) of the vehicle indicates that the roll event is continuing.