Determination of roll angle and bank angle with suspension displacement data

A method of controlling operation of a device having a body operatively connected to a plurality of wheels, the plurality of wheels being positioned on a banked surface defining a bank angle (β), a suspension system operatively connected to the plurality of wheels and having at least one suspension sensor, a controller in communication with the at least one suspension sensor and having a processor and tangible, non-transitory memory on which is recorded instructions, the method comprising:

• obtaining a suspension displacement data from the at least one suspension sensor;
• obtaining a plurality of predetermined parameters, a yaw rate (r) and a longitudinal velocity (Vx), the plurality of predetermined parameters including a first factor (A) and a second factor (B);
• obtaining the first factor (A) based at least partially on a selected bank angle (βs) and a selected roll angle (φs) corresponding to the selected bank angle such that
• (
• A
• =
• β
• s
• φ
• s
• )
• ,
• the selected bank angle (βs) being between 0 and 15 degrees, inclusive;
• determining a roll angle (φ) based at least partially on the suspension displacement data;
• determining the bank angle (β) based at least partially on the roll angle (φ), the yaw rate (r), the longitudinal velocity (Vx) and the plurality of predetermined parameters;
• and
• controlling operation of the device based partly on at least one of the roll angle (φ) and the bank angle (β).

A device comprising:

• a body operatively connected to a plurality of wheels, the plurality of wheels being positioned on a banked surface defining a bank angle (β);
• a suspension system operatively connected to the plurality of wheels and having at least one suspension sensor configured to provide suspension displacement data, the plurality of wheels including a first wheel and a second wheel;
• a first axle operatively connecting the first wheel and the second wheel;
• a controller in communication with the at least one suspension sensor and having a processor and tangible, non-transitory memory on which instructions are recorded, execution of the instructions by the processor causing the controller to:
• obtain the suspension displacement data from the at least one suspension sensor;
• obtain a plurality of predetermined parameters, a yaw rate (r) and a longitudinal velocity (Vx), the plurality of predetermined parameters including a first factor (A), a second factor (B), and a third factor (C);
• determine a roll angle (φ) based at least partially on the suspension displacement data;
• determine the bank angle (β) based at least partially on the roll angle (φ), the yaw rate (r), the longitudinal velocity (Vx) and the plurality of predetermined parameters;
• and
• control operation of the device based partly on at least one of the roll angle (φ) and the bank angle (β);
• wherein the second factor (B) is based at least partially on the first factor (A) and a gravitational constant (g) such that
• (
• B
• =
• Ag
• ⁢
• ⁢
• φ
• 0
• r
• 0
• ⁢
• V
• x
• ⁢
• 0
• )
• and r0, φ0 and Vx0 are the yaw rate, roll angle and longitudinal velocity, respectively, when the bank angle (β) is zero degrees;
• wherein the suspension displacement data includes a first displacement (ΔZLF) between respective coordinates along a z axis of a first corner (z=Z1) of the body and a center (z=zu1) of the first wheel such that ΔZLF=−(Z1−zu1);
• and
• wherein the suspension displacement data includes a second displacement (ΔZRF) between respective coordinates along the z axis of a second corner (z=Z2) of the body and a center (z=zu2) of the second wheel such that ΔZRF=−(Z2−zu2).