Vehicle lane departure warning system and method

1. A vehicle lane departure warning system comprising:

a position sensor for sensing position of a vehicle;

memory storing learned vehicle path data;

a controller for processing the sensed position and determining a stored learned vehicle path that the vehicle is travelling on, said controller comprising logic for comparing the sensed position to the stored learned vehicle path and determining if the vehicle is sufficiently departing from the stored learned path by

sensing position of a vehicle and generating position data,

processing the sensed position data of the vehicle,

determining a learned vehicle path that the vehicle is travelling on based on the sensed position data,

applying a confidence level to the learned vehicle path, wherein the confidence level provides an indication as to the number of times the vehicle path has been traveled by the vehicle,

updating a learned path when the confidence level is less than the threshold value;

storing the learned vehicle path in memory,

updating the stored learned vehicle path as the vehicle repeatedly travel on the path;

comparing the sensed position to the stored learned vehicle path,

determining whether the vehicle is sufficiently departing from the stored learned vehicle path based on the comparison, and

providing a warning signal indication output if the vehicle is determined to be departing from the stored learned vehicle path; and

an output for providing a warning signal indicative of the vehicle departing from the stored learned path.

2. The system as defined in claim 1 , wherein the position sensor comprises a global positioning system (GPS) receiver.

3. The system as defined in claim 1 , wherein the logic determines a spline path generally centered about the sensed position data and compares the path data to control limits relative to the spline path.

4. The system as defined in claim 1 , wherein the system detects a turn signal indication and disregards a lane departure warning when a turn detection signal indication is detected.

5. The system as defined in claim 1 further comprising a yaw sensor, wherein the logic compares sensed vehicle yaw to a yaw maximum value and disregards a lane departure warning when the sensed yaw exceeds the yaw threshold.

6. The system as defined in claim 1 further comprising a brake signal input, wherein the logic disregards providing a warning output when the brake signal is applied.

7. The system as defined in claim 1 , wherein the vehicle is a wheeled vehicle traveling on a roadway.

8. A method of monitoring movement of a vehicle on a roadway and warning of a lane departure, said method comprising the steps of:

sensing position of a vehicle and generating position data;

processing the sensed position data of the vehicle;

determining a learned vehicle path that the vehicle is travelling on based on the sensed position data;

applying a confidence level to the learned vehicle path, wherein the confidence level provides an indication as to the number of times the vehicle path has been traveled by the vehicle;

updating a learned path when the confidence level is less than the threshold value;

storing the learned vehicle path in memory;

updating the stored learned vehicle path as the vehicle repeatedly travel on the path;

comparing the sensed position to the stored learned vehicle path;

determining whether the vehicle is sufficiently departing from the stored learned vehicle path based on the comparison; and

providing a warning signal indication output if the vehicle is determined to be departing from the stored learned vehicle path.

9. The method as defined in claim 8 , wherein the step of sensing position of the vehicle and generating position data is performed by a GPS receiver.

10. The method as defined in claim 8 further comprising a step of comparing the confidence level to a threshold value and applying the warning output only when the confidence level exceeds the threshold.

11. The method as defined in claim 8 further comprising the step of calculating a spline path generally centered about the sensed position data and comparing the sensed position data to control limits relative to the spline path.

12. The method as defined in claim 8 further comprising the step of detecting a turn signal indication and disregarding the warning output when a turn detection signal indication is detected.

13. The method as defined in claim 8 further comprising the step of sensing vehicle yaw and comparing the sensed vehicle yaw to a yaw maximum value and disregarding a warning output when the sensed yaw exceeds the yaw threshold.

14. The method as defined in claim 8 further comprising the step of sensing vehicle braking and disregarding providing a warning output when vehicle braking is detected.

15. The method as defined in claim 8 , wherein the vehicle is a wheeled vehicle traveling on a roadway.