System and method for monitoring seat belt routing using both a webbing payout sensor and an in-cabin sensor

1. A system comprising:

a seat belt routing module configured to:

determine a routing of a seat belt relative to an occupant in a seat of a vehicle based on input from a webbing payout sensor that measures a webbing payout of the seat belt; and

determine the seat belt routing based on an input from an in-cabin sensor located within a cabin of the vehicle, wherein the in-cabin sensor includes at least one of a camera, an infrared sensor, an ultrasonic sensor, a radar sensor, and a lidar sensor;

a user interface device (UID) control module configured to control a user interface device to indicate that the seat belt is being worn improperly when:

the seat belt routing determined using at least one of the webbing payout sensor and the in-cabin sensor is improper; and

the seat belt routing determined using the webbing payout sensor corresponds to the seat belt routing determined using the in-cabin sensor; and

a sensor state module configured to activate the in-cabin sensor when a first change in the webbing payout is greater than a first delta value,

wherein the sensor state module is configured to deactivate the in-cabin sensor when, after the seat belt routing module determines the seat belt routing using the in-cabin sensor, a second change in the webbing payout is less than a second delta value.

2. The system of claim 1 further comprising a sensor state module configured to activate at least one of the webbing payout sensor and the in-cabin sensor when a buckle sensor indicates that the seat belt is buckled.

3. The system of claim 1 wherein the seat belt routing module is configured to repeatedly determine the seat belt routing based on the input from the in-cabin sensor when the in-cabin sensor is activated.

4. The system of claim 1 wherein the seat belt routing module is configured to:

determine a plurality of possible seat belt routings based on the webbing payout; and

determine that the seat belt routing determined using the webbing payout sensor corresponds to the seat belt routing determined using the in-cabin sensor when one of the plurality of possible seat belt routings match the seat belt routing determined using the in-cabin sensor.

5. The system of claim 1 wherein the seat belt routing module is configured to:

determine a plurality of possible seat belt routings based on the input from the in-cabin sensor; and

determine that the seat belt routing determined using the webbing payout sensor corresponds to the seat belt routing determined using the in-cabin sensor when one of the plurality of possible seat belt routings match the seat belt routing determined using the webbing payout sensor.

6. The system of claim 1 wherein:

when the seat belt routing determined using the webbing payout sensor does not correspond to the seat belt routing determined using the in-cabin sensor, the seat belt routing module is configured to select one of the webbing payout sensor and the in-cabin sensor as a primary sensor; and

the UID control module is configured to control the user interface device to indicate that the seat belt is being worn improperly when the seat belt routing determined using the primary sensor is improper.

7. The system of claim 6 wherein the seat belt routing module is configured to select one of the webbing payout sensor and the in-cabin sensor as the primary sensor based on at least one of:

whether the in-cabin sensor detects a shoulder webbing of the seat belt;

a confidence in the seat belt routing determined using the webbing payout sensor; and

a confidence in the seat belt routing determined using the in-cabin sensor.

8. The system of claim 6 further comprising an occupant posture module configured to determine a posture of the occupant based on the input from the in-cabin sensor, wherein the seat belt routing module is configured to select the in-cabin sensor as the primary sensor when the occupant posture is non-erect.

9. The system of claim 1 wherein the seat belt routing module is configured to;

store a relationship between the webbing payout and the seat belt routing; and

determine the seat belt routing based on the webbing payout using the stored relationship between the webbing payout and the seat belt routing.

10. The system of claim 9 wherein the seat belt routing module is configured to adjust the stored relationship when a buckle sensor indicates that the seat belt is buckled and an acceleration sensor indicates that a deceleration of the vehicle is greater than a predetermined rate.

11. The system of claim 9 wherein the seat belt routing module is configured to adjust the stored relationship when a buckle sensor indicates that the seat belt is buckled and, based on the input from the in-cabin sensor, the seat belt routing module determines that the seat belt is being properly worn.

12. The system of claim 9 wherein the seat belt routing module is configured to adjust the stored relationship when, based on the input from the in-cabin sensor, the seat belt routing module determines that the seat belt is being properly, stowed.

13. The system of claim 9 further comprising an occupant detection module configured to detect whether a child restraint seat is present in the vehicle seat, wherein the seat belt routing module is configured to adjust the stored relationship based on whether the child restraint seat is present in the vehicle seat.

14. The system of claim 9 wherein the seat belt routing module is configured to adjust the stored relationship when:

at least one of the in-cabin sensor and a seat bottom position sensor indicates that the vehicle seat has moved; and

based on the input from the in-cabin sensor, the seat belt routing module determines that the seat belt is being properly worn.

15. The system of claim 9 wherein the seat belt routing module is configured to adjust the stored relationship when:

at least one of the in-cabin sensor and a guideloop position sensor indicates that a guideloop for the seat belt has moved; and

based on the input from the in-cabin sensor, the seat belt routing module determines that the seat belt is being properly worn.

16. A system comprising:

a seat belt routing module configured to:

determine a routing of a seat belt relative to an occupant in a seat of a vehicle based on input from a webbing payout sensor that measures a webbing payout of the seat belt;

determine the seat belt routing based on an input from an in-cabin sensor located within a cabin of the vehicle, wherein the in-cabin sensor includes at least one of a camera, an infrared sensor, an ultrasonic sensor, a radar sensor, and a lidar sensor;

assign a first confidence to the seat belt routing determined using the webbing payout sensor;

assign a second confidence to the seat belt routing determined using the in-cabin sensor; and

select one of the webbing payout sensor and the in-cabin sensor as a primary sensor based on the first and second confidences; and

a user interface device (UID) control module configured to control a user interface device to indicate that the seat belt is being worn improperly when the seat belt routing determined using the primary sensor is improper.

17. The system of claim 16 wherein the seat belt routing module is configured to:

select the webbing payout sensor as the primary sensor when the first confidence is greater than the second confidence; and

select the in-cabin sensor as the primary sensor when the second confidence is greater than the first confidence.

18. The system of claim 16 wherein the seat belt routing module is configured to:

assign the first confidence based on whether the seat belt routing determined using the webbing payout sensor is a lap webbing routing or a shoulder webbing routing; and

assign the second confidence based on whether a field of view of the in-cabin sensor is obstructed.

19. A system comprising:

a seat belt routing module configured to:

determine a routing of a seat belt relative to an occupant in a seat of a vehicle based on input from a webbing payout sensor that measures a webbing payout of the seat belt; and

determine the seat belt routing based on an input from an in-cabin sensor located within a cabin of the vehicle, wherein the in-cabin sensor includes at least one of a camera, an infrared sensor, an ultrasonic sensor, a radar sensor, and a lidar sensor;

a user interface device (UID) control module configured to control a user interface device to indicate that the seat belt is being worn improperly when:

the seat belt routing determined using at least one of the webbing payout sensor and the in-cabin sensor is improper; and

the seat belt routing determined using the webbing payout sensor corresponds to the seat belt routing determined using the in-cabin sensor,

wherein;

when the seat belt routing determined using the webbing payout sensor does not correspond to the seat belt routing determined using the in-cabin sensor, the seat belt routing module is configured to select one of the webbing payout sensor and the in-cabin sensor as a primary sensor; and

the UID control module is configured to control the user interface device to indicate that the seat belt is being worn improperly when the seat belt routing determined using the primary sensor is improper, and

at least one of:

(a) the seat belt routing module is configured to select one of the webbing payout sensor and the in-cabin sensor as the primary sensor based on at least one of:

whether the in-cabin sensor detects a shoulder webbing of the seat belt;

a confidence in the seat belt routing determined using the webbing payout sensor; and

a confidence in the seat belt routing determined using the in-cabin sensor; and

(b) an occupant posture module configured to determine a posture of the occupant based on the input from the in-cabin sensor, wherein the seat belt routing module is configured to select the in-cabin sensor as the primary sensor when the occupant posture is non-erect.

20. A system comprising:

a seat belt routing module configured to:

determine a routing of a seat belt relative to an occupant in a seat of a vehicle based on input from a webbing payout sensor that measures a webbing payout of the seat belt; and

determine the seat belt routing based on an input from an in-cabin sensor located within a cabin of the vehicle, wherein the in-cabin sensor includes at least one of a camera, an infrared sensor, an ultrasonic sensor, a radar sensor, and a lidar sensor;

a user interface device (UID) control module configured to control a user interface device to indicate that the seat belt is being worn improperly when:

the seat belt routing determined using at least one of the webbing payout sensor and the in-cabin sensor is improper; and

the seat belt routing determined using the webbing payout sensor corresponds to the seat belt routing determined using the in-cabin sensor,

wherein the seat belt routing module is configured to:

store a relationship between the webbing payout and the seat belt routing; and

determine the seat belt routing based on the webbing payout using the stored relationship between the webbing payout and the seat belt routing; and

at least one of:

(a) the seat belt routing module is configured to adjust the stored relationship when a buckle sensor indicates that the seat belt is buckled and an acceleration sensor indicates that a deceleration of the vehicle is greater than a predetermined rate;

(b) the seat belt routing module is configured to adjust the stored relationship when a buckle sensor indicates that the seat belt is buckled and, based on the input from the in-cabin sensor, the seat belt routing module determines that the seat belt is being properly worn;

(c) the seat belt routing module is configured to adjust the stored relationship when, based on the input from the in-cabin sensor, the seat belt routing module determines that the seat belt is being properly stowed;

(d) the system further comprises an occupant detection module configured to detect whether a child restraint seat is present in the vehicle seat, wherein the seat belt routing module is configured to adjust the stored relationship based on whether the child restraint seat is present in the vehicle seat;

(e) the seat belt routing module is configured to adjust the stored relationship when:

at least one of the in-cabin sensor and a seat bottom position sensor indicates that the vehicle seat has moved; and

based on the input from the in-cabin sensor, the seat belt routing module determines that the seat belt is being properly worn; and

(f) the seat belt routing module is configured to adjust the stored relationship when:

at least one of the in-cabin sensor and a guideloop position sensor indicates that a guideloop for the seat belt has moved; and

based on the input from the in-cabin sensor, the seat belt routing module determines that the seat belt is being properly worn.