Dynamic brake biasing for articulating vehicles

1 . A method comprising:

measuring a wheel speed of at least one wheel of an articulating vehicle having a front frame and a rear frame connected by an articulation joint, the vehicle having front and rear axles and the at least one wheel mounted on one of the front and rear axles;

determining whether the measured wheel speed exceeds a slip value threshold; and

if the measured wheel speed exceeds the slip value threshold,

calculating a wheel speed control value based on a center of gravity of the vehicle, a location of the at least one wheel relative to an axis of the vehicle, and at least one of:

a vehicle mass of the vehicle,

a vehicle slope of the vehicle,

an articulation angle of the vehicle,

a vehicle speed of the vehicle, and

a vehicle direction of the vehicle; and

controlling a desired wheel speed of the at least one wheel based on the wheel speed control value.

2 . The method of claim 1 , wherein controlling the desired wheel speed of the at least one wheel based on the wheel speed control value comprises slowing a rotation of the at least one wheel until the measured wheel speed falls below the slip value threshold.

3 . The method of claim 1 , wherein the slip value threshold is based on the vehicle speed.

4 . The method of claim 1 , wherein the wheel speed control value comprises a brake pressure for a friction brake.

5 . The method of claim 1 , wherein the wheel speed control value comprises a torque for an electric motor.

6 . The method of claim 1 , wherein the center of gravity is determined using at least one inertial motion unit.

7 . The method of claim 1 , further comprising, if the measured wheel speed exceeds the slip value threshold, calculating the wheel speed control value based on a lateral location of the at least one wheel relative to a longitudinal axis of the vehicle.

8 . The method of claim 2 , wherein, after the measured wheel speed falls below the slip value threshold, the method further comprises:

determining whether the measured wheel speed exceeds the slip value threshold.

9 . The method of claim 2 , further comprises actuating a friction brake of the vehicle to slow down the rotation of the at least one wheel.

10 . The method of claim 9 , further comprising actuating the friction brake to stop the rotation of the at least one wheel.

11 . The method of claim 9 , further comprising driving, by an electric motor, the at least one wheel.

12 . The method of claim 9 , wherein slowing the rotation of the at least one wheel until the measured wheel speed falls below the slip value threshold comprises at least one of slowing and reversing a rotation of an electric motor.

13 . The method of claim 12 , wherein slowing the rotation of the at least one wheel until the measured wheel speed falls below the slip value threshold comprises at least one of: actuating the friction brake, and at least one of slowing and reversing a rotation of the electric motor.

14 . A dynamic brake biasing system comprising:

at least one wheel of an articulating vehicle having a front frame, a rear frame connected by an articulation joint, front and rear axles, the at least one wheel mounted on one of the front and rear axles and configured to be stopped by a friction brake or driven by an electric motor, the articulating vehicle having a center of gravity, a vehicle mass, a vehicle slope, an articulation angle, a vehicle speed, and a vehicle direction; and

a controller configured to:

measure a wheel speed of the at least one wheel as a measured wheel speed,

determine whether the measured wheel speed exceeds a slip value threshold, and

if the measured wheel speed exceeds the slip value threshold,

calculate a wheel speed control value based on the center of gravity, a location of the at least one wheel relative to an axis of the vehicle, and at least one of: the vehicle mass, the vehicle slope, the articulation angle, the vehicle speed, and the vehicle direction, and

control a desired wheel speed of the at least one wheel based on the wheel speed control value.

15 . The system of claim 14 , wherein control the desired wheel speed of the at least one wheel based on the wheel speed control value comprises slowing a rotation of the at least one wheel until the measured wheel speed falls below the slip value threshold.

16 . The system of claim 14 , wherein the at least one wheel is configured to be stopped by the friction brake, and

wherein slowing a rotation of the at least one wheel until the measured wheel speed falls below the slip value threshold comprises actuating the friction brake.

17 . The system of claim 14 , wherein the at least one wheel is configured to be driven by the electric motor, and

wherein slowing a rotation of the at least one wheel until the measured wheel speed falls below the slip value threshold comprises at least one of slowing and reversing a rotation of the electric motor.

18 . A controller configured to:

receive a measured wheel speed of at least one wheel of an articulating vehicle having a front frame, a rear frame connected by an articulation joint, front and rear axles, the at least one wheel mounted on one of the front and rear axles and configured to be stopped by a friction brake or driven by an electric motor;

receive a vehicle mass of the vehicle, a vehicle slope of the vehicle, an articulation angle of the vehicle, a vehicle speed of the vehicle, and a vehicle direction of the vehicle;

determine whether the measured wheel speed exceeds a slip value threshold; and

if the measured wheel speed exceeds the slip value threshold,

calculate a wheel speed control value based on a center of gravity of the vehicle, a location of the at least one wheel relative to an axis of the vehicle, and at least one of the vehicle mass, the vehicle slope, the articulation angle, the vehicle speed, and the vehicle direction; and

control a desired wheel speed of the at least one wheel based on the wheel speed control value.

19 . The controller of claim 18 , wherein control the desired wheel speed of the at least one wheel based on the wheel speed control value comprises slowing the at least one wheel using a friction brake and/or an electric motor until the measured wheel speed falls below the slip value threshold.

20 . The controller of claim 18 , wherein the controller is configured to receive the center of gravity from at least one inertial motion unit.