Attitude sensing system for an automotive vehicle

A control system for an automotive vehicle having a vehicle body comprising;

• a roll angular rate sensor generating a roll angular rate signal corresponding to a roll angular motion of the vehicle body;
• a yaw angular rate sensor generating a yaw motion signal corresponding to a yaw motion of the vehicle body;
• a lateral accelerometer generating a lateral acceleration signal corresponding to a lateral acceleration of a center of gravity of the vehicle body;
• a longitudinal accelerometer generating a longitudinal acceleration signal corresponding to the longitudinal acceleration of the center of gravity of the vehicle body;
• a wheel speed sensor generating a wheel speed signal corresponding to a wheel speed of the vehicle;
• and
• a controller coupled to said roll angular rate sensor, said yaw angular rate sensor, said lateral accelerometer, said longitudinal accelerometer, and said wheel speed sensor, said controller comprising an anti-integration drift filter and a steady state recovery filter, said controller determining a roll attitude angle, a pitch attitude angle and a yaw attitude angle in response to said roll angular rate signal, said yaw angular rate signal, said lateral acceleration signal, said longitudinal acceleration signal, said wheel speed signal, said anti-integration drift filter and said steady state recovery filter.

A method for operating a vehicle control system comprising:

• generating a plurality of sensor signals in response to vehicle conditions comprising a roll rate sensor signal, a vehicle velocity signal and a longitudinal acceleration signal;
• generating a yaw rate sensor signal;
• estimating a vehicle pitch angle estimation in response to said plurality of sensor signals;
• determining a transient roll attitude angle in response to said pitch angle estimation, roll rate sensor signal, yaw rate sensor signal;
• determining a steady state roll attitude angle in response to said pitch angle estimation, vehicle velocity signal and longitudinal acceleration signal;
• determining a roll attitude angle estimation in response to the steady state roll attitude angle and the transient roll attitude angle;
• determining a pitch rate estimation in response to the roll and pitch angle estimation and the yaw rate sensor signal;
• and
• activating a safety device in response to the roll attitude angle estimation.

A method of operating a safety device for an automotive vehicle comprising the steps of:

• determining a yaw rate for the vehicle;
• determining a roll rate for the vehicle;
• determining a lateral acceleration for the vehicle;
• determining a longitudinal acceleration of the vehicle;
• determining vehicle speed;
• generating a rollover signal in response to said yaw rate, roll rate, lateral acceleration, longitudinal acceleration, vehicle speed, an anti-integration drift filter, and a steady state recovery filter;
• and
• operating a safety device in response to said rollover signal.

A method of operating a safety device for an automotive vehicle comprising the steps of:

• determining a first angular rate for the vehicle;
• determining a first acceleration for the vehicle;
• determining a second acceleration for the vehicle;
• determining vehicle speed;
• and
• generating a rollover signal in response to said first angular rate, said second angular rate, said first acceleration, said second acceleration, a vehicle speed, an anti- integration drift filter, and a steady state recovery filter;
• and
• operating a safety device in response to said rollover signal.