Methods and system for crossing prediction
View Patent ↗Various methods and systems are provided for predicting crossing times. In one embodiment, a method comprises determining a vehicle position of a vehicle from sensed data, filtering the vehicle position, determining vehicle velocity based on the filtered vehicle position, filtering the vehicle velocity to a greater extent than vehicle position is filtered, at least above a threshold frequency, and determining a time-to-crossing based on the filtered vehicle position and filtered velocity.
1. A method carried out by non-transitory instructions stored on a controller, comprising:
determining a vehicle position of a vehicle from sensed data;
filtering the vehicle position;
determining vehicle velocity based on the filtered vehicle position;
filtering the vehicle velocity to a greater extent than the vehicle position is filtered, at least above a threshold frequency; and
determining a time-to-crossing based on the filtered vehicle position and filtered vehicle velocity,
further comprising:
when the time-to-crossing reaches a threshold travel time, sending a signal to activate warning equipment at a crossing that the vehicle is approaching,
wherein the vehicle is a rail vehicle.
2. The method of claim 1 , wherein determining the vehicle velocity based on the filtered vehicle position further comprises differentiating the filtered vehicle position with respect to time.
3. The method of claim 1 , wherein the time-to-crossing is a travel time from a predetermined position for the vehicle to reach a crossing between a vehicle path and an alternate path.
4. The method of claim 3 , wherein the vehicle position is an average percentage distance from the crossing relative to a shunt on the vehicle path.
5. The method of claim 1 , wherein the filtered velocity comprises a non-linear weighted average velocity of the vehicle.
6. The method of claim 5 , wherein the non-linear weighted average velocity comprises a weighted average of a current velocity and a plurality of previous velocities.
7. The method of claim 6 , wherein the current velocity comprises a first, largest portion of the weighted average, and wherein the plurality of previous velocities comprises a smaller portion of the weighted average.
8. The method of claim 5 , wherein determining the non-linear weighted average velocity further comprises averaging a plurality of calculated non-linear weighted average velocities.
9. A crossing system, comprising:
warning equipment controlling a crossing between a first path and a second path; and
a controller including instructions to:
determine a filtered velocity of a vehicle traveling on the first path by differentiating a filtered vehicle position with respect to time;
based on the filtered velocity, determine a time-to-crossing for the vehicle to reach the crossing; and
respond to the vehicle reaching a threshold time-to-crossing by sending a signal to activate the warning equipment,
wherein, above a threshold frequency, the filtered velocity is filtered to a greater extent than the filtered vehicle position, and wherein below the threshold frequency, the filtered velocity is filtered to a similar extent as the vehicle position, and
wherein the vehicle is a rail vehicle.
10. The crossing system of claim 9 , wherein the filtered velocity comprises a non-linear weighted average velocity.
11. The crossing system of claim 10 , wherein the non-linear weighted average velocity comprises a weighted average of a current velocity and a plurality of previous velocities.
12. The crossing system of claim 11 , wherein the current velocity comprises a first, largest portion of the weighted average, a first and second of the previous velocities immediately previous to the current velocity each comprise a second, smaller portion of the weighted average, and a third, fourth, and fifth of the previous velocities immediately previous to the first and second previous velocities each comprise a third, smallest portion of the weighted average.
13. The crossing system of claim 9 , wherein the filtered vehicle position is an average percentage distance from the crossing relative to a shunt of the first path upstream of the crossing.
14. The crossing system of claim 9 , wherein the filtered vehicle position has a maximum value.
15. A method carried out by non-transitory instructions stored on a controller, comprising:
determining a vehicle position of a vehicle with respect to a crossing on a vehicle path;
determining a non-linear weighted average velocity of the vehicle based on a change of vehicle position;
responsive to the change of vehicle position less than a first threshold, determining a time-to-crossing based on the vehicle position and the non-linear weighted average velocity and sending a signal to activate warning equipment at the crossing in response to the time-to-crossing reaching a second threshold; and
responsive to the change of vehicle position greater than the first threshold, waiting until the change of vehicle position is less than the first threshold before determining the time-to-crossing,
wherein the vehicle is a rail vehicle.
16. The method of claim 15 , wherein the path is rail track.
17. The method of claim 15 , wherein the second threshold is preset by a user.
18. The method of claim 15 , wherein the vehicle position comprises an average percent distance to the crossing relative to a shunt of the vehicle path upstream of the crossing.
19. The method of claim 15 , wherein the vehicle position has a maximum value.