Method for determining the roll angle of a vehicle using an estimation of road bank angle

A method of determining a roll angle comprising:

• providing a lateral acceleration signal corresponding to a lateral acceleration of the vehicle;
• providing a yaw rate signal corresponding to a yaw rate of the vehicle;
• providing a steering wheel signal responsive to a sensed steering wheel angle of the vehicle;
• providing a speed signal corresponding to a vehicle speed;
• calculating a first bank angle estimate dependent on said lateral acceleration signal;
• calculating a second bank angle estimate dependent on said yaw rate signal;
• calculating a third bank angle estimate dependent on both said lateral acceleration signal and the yaw rate signal;
• calculating a dynamic compensation factor as a function of said first bank angle estimate, said second bank angle estimate and said third bank angle estimate;
• decomposing the third bank angle estimate into a plurality of third bank angle frequency bands;
• reducing each of the plurality of third bank angle frequency bands in response to a multiplicative factor, said multiplicative factor being a function of said dynamic compensation factor to obtain a plurality of reduced third bank angles;
• and
• calculating a final bank angle bias estimate based on a sum of the plurality of reduced third bank angles
• calculating a suspension reference roll angle in response to said lateral acceleration signal and a spring mass model;
• and
• calculating a conservative bank angle estimate signal in response to the final bank angle bias estimate and the suspension reference roll angle.

A method of determining a roll angle of a vehicle comprising:

• providing a lateral acceleration signal corresponding to a lateral acceleration of the vehicle;
• providing a yaw rate signal corresponding to a yaw rate of the vehicle;
• providing a steering wheel signal responsive to a sensed steering wheel angle of the vehicle;
• providing a speed signal corresponding to a vehicle speed;
• providing a roll rate signal corresponding to the roll rate of the vehicle;
• calculating a first roll angle signal in response to said roll rate signal;
• calculating a second roll angle signal corresponding to a suspension reference roll angle in response to said lateral acceleration signal and a spring mass model;
• calculating a first bank angle estimate dependent on said lateral acceleration signal;
• calculating a second bank angle estimate dependent on said yaw rate signal;
• calculating a third bank angle estimate dependent on both said lateral acceleration signal and the yaw rate signal;
• calculating a dynamic compensation factor as a function of said first bank angle estimate, said second bank angle estimate and said third bank angle estimate;
• decomposing the third bank angle estimate into a plurality of third bank angle frequency bands;
• reducing each of the plurality of third bank angle frequency bands in response to a multiplicative factor, said multiplicative factor being a function of said dynamic compensation factor to obtain a plurality of reduced third bank angles;
• and
• determining a final bank angle bias estimate signal based on a sum of the plurality of reduced third bank angles;
• and
• determining a final roll angle estimate in response to the first roll angle signal, the second roll angle signal, and the final bank angle bias estimate.