System and method for determining grade and acceleration due to motoring and braking

1. A position-tracking system, comprising:

a vehicle having a position-tracking computer system and a liquid capacitive inclinometer sensor (LCIS) component mounted to the vehicle having and communicatively connected to the position-tracking computer system, wherein the LCIS component is aligned with a principal axis of the vehicle, wherein the LCIS component includes one or more LCIS units aligned with the principal axis and configured to measure acceleration along the principal axis (a x ).

2. The system of claim 1 , further comprising an accelerometer component aligned with the principal axis of the vehicle and configured to measure the acceleration along the principal axis (a x ), the accelerometer component mounted to the vehicle and communicatively connected to the position-tracking computer system.

3. The system of claim 2 , wherein the accelerometer component is further configured to measure acceleration in a direction perpendicular to the principal axis (a z ).

4. The system of claim 1 , wherein the LCIS component comprises at least two LCIS units aligned with the principal axis and configured to measure the acceleration along the principal axis (a x ).

5. The system of claim 4 , wherein a first LCIS unit of the at least two LCIS units is mounted at an offset angle (β) from a second LCIS unit of the at least two LCIS units.

6. The system of claim 4 , further comprising an accelerometer component aligned with the principal axis of the vehicle and configured to measure the acceleration along the principal axis (a x ).

7. A method, comprising:

recording motion parameters associated with a position-tracking system of a vehicle;

calculating, based on the recorded motion parameters, a grade (θ grade ) in relation to a horizon or a level position;

calculating, based on the motion parameters and the grade, acceleration due to motoring and braking (a MB );

determining a vehicle position based on the grade and/or the calculated acceleration due to motoring and braking; and

performing a rail operation based on the determined vehicle position.

8. The method of claim 7 , further comprising transmitting a MB and θ grade to a vehicle position monitor computer system.

9. The method of claim 7 , wherein the recording motion parameters associated with the position-tracking system of the vehicle further comprises determining an acceleration along a principal axis (a x ).

10. The method of claim 9 , wherein the recording motion parameters associated with the position-tracking system of the vehicle further comprises determining an acceleration along an axis perpendicular to the principal axis (a z ).

11. The method of claim 10 , wherein calculating the grade further comprises calculating an arc-cosine (cos −1 ) of a z /(g), where g is an acceleration due to gravity.

12. The method of claim 10 , wherein the recording motion parameters further comprises measuring a height of a liquid in an LCIS unit of the position-tracking system of the vehicle at opposite sides of the LCIS, wherein the LCIS is aligned with the principal axis of the vehicle.

13. The method of claim 7 , wherein the recording the motion parameters associated with the position-tracking system of the vehicle comprises:

recording, where the position-tracking system includes a first position-tracking system and a second position-tracking system, and the motion parameters include a first set of motion parameters from the first-position tracking system and a second set of motion parameters from the second position-tracking system.

14. A method, comprising

recording, for a vehicle having a first position-tracking system and a second position tracking system, a first set of motion parameters from the first position-tracking system and a second set of motion parameters from the second position-tracking system;

calculating a first grade (θ grade(1) ) in relation to a horizon or a level position and a first acceleration due to motoring and braking (a MB(1) ) based on the first set of motion parameters;

calculating a second grade (θ grade(2) ) in relation to the horizon or the level position and a second acceleration due to motoring and braking (a MB(2) ) based on the second set of motion parameters;

determining whether the first grade and the second grade match within a first measurement tolerance; and

determining whether the first acceleration due to motoring and braking (a MB(2) ) match within a second measurement tolerance,

determining, in response to determining that a MB(1) and a MB(2) are within a third measurement tolerance; a vehicle position; and

performing a rail operation based on the determined vehicle position.

15. The method of claim 14 , further comprising reporting a measurement error upon determining that the first grade does not match the second grade.

16. The method of claim 14 , further comprising reporting a measurement error upon determining that the first acceleration due to motoring and braking does not match the second acceleration due to motoring and braking.

17. The method of claim 14 , further comprising reporting a matching acceleration due to motion and braking, and a matching grade, to a vehicle position monitor computer system.

18. The method of claim 14 , wherein determining the first grade and the second grade further comprises recording a first height and a second height of a first liquid in a first liquid capacitive inclinometer sensor (LCIS) unit, and recording a third height and a fourth height of a second liquid in a second LCIS unit, wherein the first LCIS unit and the second LCIS unit are aligned with a principal axis of the vehicle.

19. The method of claim 14 , wherein recording motion parameters further comprises measuring acceleration along a principal axis (a x ) of the vehicle with a single-axis accelerometer.

20. The method of claim 14 , wherein recording motion parameters further comprises measuring acceleration along a principal axis (a x ) of the vehicle, and acceleration perpendicular to the principal axis of the vehicle (a z ) with a dual-axis accelerometer.