Computing train route for PTC onboard system to navigate over a loop track

1. A train navigation method for safely navigating a track loop in a railway, the method comprising:

determining, by a computing system having one or more processors, a head end location of a train navigating a track block in a plurality of track blocks associated with the track loop in the railway;

determining, by the computing system, a train route from the head end location of the train, including a forward path and a rearward path, the train route based on a position of a switch in the plurality of track blocks associated with the track loop in the railway;

dynamically generating, by the computing system, an updated train route as the train traverses the railway, based on a continuously updated head end location as the train traverses the railway relative to the position of the switch; and

safely traversing the track loop in the railway based upon the updated train route.

2. The train navigation method of claim 1 , further comprising:

identifying, by the computing system, the switch as a looping switch based on the switch in a location of the track block starting the track loop in the railway and the track block ending the track loop in the railway; and

determining the train route by determining the position of the switch in a subset of track blocks of the plurality of track blocks in the forward path, wherein the subset of track blocks of the plurality of track blocks in the forward path are before the switch and the subset of track blocks of the plurality of track blocks in the rearward path are in a location after the switch.

3. The method of claim 2 , wherein the train route includes at least one of the forward path in at least one track block of the plurality of track blocks in an advance of the train, a path in at least one track block of the plurality of track blocks behind the end of the train, an occupied path in at least one track block of the plurality of track blocks under the train, or any combination, wherein at least one of the forward path or the rearward path includes the occupied path under the train.

4. The method of claim 3 , wherein determining route data comprises:

determining a portion of the rearward path starting at a head of the train, including one or more segments of track and one or more switches, the one or more switches associated with track segments longer than a length of the train to cover;

determining the forward path extending in advance of the head of the train, including one or more segments of track and one or more switches; and

determining the rearward path by combining the portion of the rearward path with a remaining rearward path extending behind the end of the train.

5. The method of claim 4 , wherein the forward path includes the last track block preceding a looping switch if the looping switch is already included in the rearward path, and

wherein the remaining rearward path includes the last track block preceding the looping switch if the looping switch is already included in the forward path generated.

6. The method of claim 5 , wherein determining the forward path, further comprises determining the forward path includes the segment of track associated with the head of the train.

7. The method of claim 5 , wherein safely traversing the track loop based upon the updated route is accomplished by operating the train on the updated route including predictive enforcement in advance of the train, further comprising:

controlling the train in the track loop based on determining the length of the subset of blocks in the track loop is greater than the length of the train.

8. The method of claim 7 , wherein safely traversing the track loop includes operating the train on the updated route based on reactive protection associated with one or more portions of the train, comprising:

predicting an upcoming condition in the forward path; and

controlling the train based on the upcoming condition.

9. The method of claim 8 , comprising:

automatically issuing a train control command based on a condition in the rearward path under any portion of the train.

10. An on-board navigation system for generating a train route in a railway, comprising:

a computing system including one or more processors configured to:

determine a head end location of a train navigating a track block in a plurality of track blocks associated with a track loop in the railway;

determine the train route from the head end location of the train including a forward path and a rearward path, the train route based on a position of a switch in the plurality of track blocks associated with the track loop in the railway;

dynamically generate an updated train route as the train traverses the railway, based on a continuously updated head end location as the train traverses the railway relative to the position of the switch; and

safely traverse the track loop in the railway based upon the updated train route.

11. The on-board navigation system of claim 10 , wherein the computing system is further configured to:

identify the switch as a looping switch based on the switch in a location of the track block starting the track loop in the railway and the track block ending the track loop in the railway; and

determine the train route by determining the position of the switch in a subset of track blocks of the plurality of track blocks in the forward path, wherein the subset of track blocks of the plurality of track blocks in the forward path are before the switch and the subset of track blocks of the plurality of track blocks in the rearward path are in a location after the switch.

12. The on-board navigation system of claim 11 , wherein the train route includes at least one of the forward path in at least one track block of the plurality of track blocks in an advance of the train, a path in at least one track block of the plurality of track blocks behind the end of the train, an occupied path in at least one track block of the plurality of track blocks under the train, or any combination, wherein at least one of the forward path or the rearward path includes the occupied path under the train.

13. The on-board navigation system of claim 12 , wherein the computing system is further configured to determine the route data by:

determining a portion of the rearward path starting at a head of the train, including one or more segments of track and one or more switches, the one or more switches associated with track segments longer than a length of the train to cover;

determining the forward path extending in advance of the head of the train, including one or more segments of track and one or more switches; and

determining the rearward path by combining the portion of the rearward path with a remaining rearward path extending behind the end of the train.

14. The on-board navigation system of claim 13 , wherein the forward path includes a last track block preceding the looping switch if the looping switch is already included in the rearward path and the remaining rearward path includes the last track block preceding the looping switch if the looping switch is already included in the forward path generated.

15. The on-board navigation system of claim 14 , wherein the forward path includes the segment of track associated with the head of the train.

16. The on-board navigation system of claim 15 , wherein the computing system is further configured to safely traverse the track loop based upon the updated route by:

operating the train on the updated route including predictive enforcement in advance of the train; and

predicting the upcoming condition in the forward path; and

controlling the train based on the upcoming condition.

17. The on-board navigation system of claim 16 , wherein the computing system is further configured to:

operate the train on the updated route based on reactive protection associated with one or more portions of the train; and

control the train in the track loop based on determining the length of the subset of blocks in the track loop is greater than the length of the train.

18. An on-board dynamic train control method for safely traversing a track loop in a railway, the method comprising:

determining, by a computing system having one or more processors, route data including a first track block in a forward path of a looping switch in a track loop;

generating, by the computing system, an updated route based on the route data, the updated route including the first track block in a rearward path of the updated route data based on an updated position of the train relative to the looping switch;

determining, by an on-board computer having one or more processors, total route distance of the track loop; and

safely traversing the track loop based upon the updated route.

19. The method of claim 18 , wherein safely traversing the track loop further comprises:

operating the train on the updated route based on reactive protection associated with one or more portions of the train;

predicting an upcoming condition in the forward path based on the distance of the track loop; and

controlling the train based on the upcoming condition.

20. The method of claim 18 , wherein safely traversing the track loop further comprises:

operating the train on the updated route including predictive enforcement in advance of the train, further comprising:

determining the looping switch in the railway associated with a segment of track for entering the track loop in the railway; and

safely traversing the track loop based upon the updated train route by controlling the train in the track loop based on determining a length of a subset of blocks in the track loop is greater than the length of the train.