Control algorithm and intrusive state-detection diagnostic for sensorless driveline disconnect

1. A method for engaging a driveline disconnect associated with a vehicle, comprising:

determining a target motor speed based on a wheel speed and a speed delta;

controlling, via a control system associated with the vehicle, a motor speed, associated with a motor assembly, to achieve the target motor speed;

facilitating, via the control system, an engagement of the driveline disconnect to couple the motor assembly with a corresponding wheel;

monitoring, via the control system, the motor speed, associated with the motor assembly, in response to the engagement of the driveline disconnect; and

determining, via the control system, that the engagement of the driveline disconnect is successful based on a motor speed response.

2. The method of claim 1 , wherein determining that the engagement is successful based on the motor speed response comprises determining that the engagement is successful when the motor speed response indicates a presence of a load connected to the driveline disconnect.

3. The method of claim 2 , further comprising determining the speed delta based on a vehicle speed.

4. The method of claim 3 , wherein determining the speed delta based on the vehicle speed comprises:

comparing the vehicle speed to a threshold;

when the vehicle speed is below the threshold, selecting a first speed delta as the speed delta; and

when the vehicle speed is above the threshold, selecting a second speed delta as the speed delta, wherein the second speed delta is greater than the first speed delta.

5. The method of claim 1 , wherein determining that the engagement of the driveline disconnect is successful comprises:

determining that the motor speed response does not indicate a successful engagement;

applying a torque impulse to the motor assembly;

determining an impulse motor speed response to the torque impulse; and

determining that the engagement is successful based on the impulse motor speed response.

6. The method of claim 5 , wherein determining that the engagement is successful based on the impulse motor speed response comprises determining that the engagement is successful when the impulse motor speed response indicates a presence of a load connected to the driveline disconnect.

7. The method of claim 1 , further comprising applying a diagnostic threshold to determine when the motor speed achieves the target motor speed corresponding to the speed delta.

8. The method of claim 7 , wherein the diagnostic threshold represents a maximum allowable steady-state error corresponding to the target motor speed and the motor speed that is controlled.

9. The method of claim 7 , wherein applying the diagnostic threshold is based on a size of an error in the motor speed.

10. The method of claim 1 , further comprising receiving the wheel speed.

11. The method of claim 10 , wherein the target motor speed corresponds to a speed less than the wheel speed.

12. The method of claim 1 , further comprising:

determining whether the motor speed and the corresponding wheel speed are well-correlated,

wherein determining whether the engagement is successful is further based on determining whether the motor speed and the corresponding wheel speed are well-correlated.

13. The method of claim 1 , wherein facilitating the engagement of the driveline disconnect to couple the motor assembly with the corresponding wheel comprises actuating struts of a pocket plate to engage with notches of a notch plate.

14. A system for engaging a driveline disconnect associated with a vehicle, comprising:

a motor;

a sensorless disconnect; and

processing circuitry configured to:

determine a target motor speed based on a wheel speed and a speed delta;

control a motor speed, associated with a motor assembly, to achieve the target motor speed;

facilitate an engagement of the sensorless disconnect to couple the motor assembly with a corresponding wheel;

monitor the motor speed, associated with the motor assembly, in response to the engagement of the sensorless disconnect; and

determine that the engagement of the sensorless disconnect is successful based on a motor speed response.

15. The system of claim 14 , wherein the processing circuitry is further configured to determine the speed delta based on a vehicle speed.

16. The system of claim 15 , wherein the processing circuitry is configured to determine the speed delta based on the vehicle speed by:

comparing the vehicle speed to a threshold;

when the vehicle speed is below the threshold, selecting a first speed delta as the speed delta; and

when the vehicle speed is above the threshold, selecting a second speed delta as the speed delta, wherein the second speed delta is greater than the first speed delta.

17. The system of claim 14 , wherein the processing circuitry is configured to determine that the engagement is successful by:

determining that the motor speed response does not indicate a successful engagement;

applying a torque impulse to the motor;

determining an impulse motor speed response to the torque impulse; and

determining that the engagement is successful based on the impulse motor speed response.

18. The system of claim 14 , wherein the processing circuitry is further configured to receive the wheel speed.

19. The system of claim 14 , wherein facilitating the engagement of the sensorless disconnect to couple the motor assembly with the corresponding wheel comprises actuating struts of a pocket plate to engage with notches of a notch plate.

20. A vehicle, comprising:

a first motor coupled to a first wheel via a first disconnect;

a second motor coupled to a second wheel via a second disconnect; and

processing circuitry configured to:

determine a target motor speed based on a wheel speed and a speed delta;

control a motor speed of the first or the second motor to achieve the target motor speed;

facilitate an engagement of the first or the second disconnect to couple the first motor with the first wheel or the second motor with the second wheel;

monitor the motor speed of the first or the second motor in response to the engagement of the first or the second disconnect; and

determine that the engagement of the first or the second disconnect is successful based on a motor speed response.

21. The vehicle of claim 20 , wherein the first wheel comprises a rear left wheel of the vehicle and the second wheel comprises a rear right wheel of the vehicle.

22. The vehicle of claim 20 , wherein the processing circuitry is configured to engage the first disconnect and the second disconnect in response to the vehicle transitioning to four-wheel drive.