SYSTEM AND METHOD FOR DETERMINING A QUALITY OF A LOCATION ESTIMATION OF A POWERED SYSTEM

• US 20090234523A1
• Filed: 03/13/2008
• Published: 09/17/2009
• Est. Priority Date: 03/13/2008
• Status: Active Grant

• Current Assignee: General Electric Company
• Original Assignee: General Electric Company
• Inventors: Kumar, Ajith Kuttannair, Nandedkar, Vishram Vinayak
• Granted Patent: US 8,190,312 B2
• Time in Patent Office: Days
• US Class Current: 701/20
• CPC Class Codes: B61L 25/021 Measuring and recording of train speed
• CPC Class Codes: B61L 25/025 Absolute localisation, e.g. providing geodetic coordinates
• CPC Class Codes: B61L 25/026 Relative localisation, e.g. using odometer

Abstract

A system is provided for determining a quality of a location estimation of a powered system at a location. The system includes a first sensor configured to measure a first parameter of the powered system at the location. The system further includes a second sensor configured to measure a second parameter of the powered system at the location. The system further includes a second controller configured to determine the location estimation of the powered system and the quality of the location estimation, based upon a first location of the powered system based on the first parameter, and a second location of the powered system based on the second parameter of the powered system. A method is also provided for determining a quality of a location estimation of a powered system at a location.

Claims

1. A system for determining a quality of a location estimation of a powered system at a location, said system comprising:

a first sensor configured to measure a first parameter of said powered system at said location;

a second sensor configured to measure a second parameter of said powered system at said location; and

a second controller configured to determine said location estimation of said powered system and said quality of the location estimation, based upon a first location of said powered system based on said first parameter, and a second location of said powered system based on said second parameter of said powered system.

2. The system of claim 1, wherein:

said powered system is a rail vehicle, said location estimation is a distance estimation of said rail vehicle at a location along a route;

said first sensor is configured to measure the first parameter of said rail vehicle at said location along said route;

said second sensor is configured to measure the second parameter of said rail vehicle at said location along said route; and

said second controller is configured to determine said distance estimation of said rail vehicle along the route and said quality of the distance estimation, based upon a first distance of said rail vehicle along the route based on said first parameter, and a second distance of said rail vehicle along the route based on said second parameter of said rail vehicle.

3. The system of claim 2, wherein:

said first sensor is a speed sensor configured to measure a speed of said rail vehicle at said location along the route;

said second sensor is a position determination device configured to provide a measured position of said rail vehicle; and

said second controller is configured to determine said distance estimation and said quality of the distance estimation, based upon said first distance based on said rail vehicle speed, and said second distance based on said measured position of said rail vehicle.

4. The system of claim 3, wherein said rail vehicle is a train having a plurality of locomotives, each locomotive including at least one speed sensor, at least one position determination device, and said second controller to determine said distance estimation and said quality of the distance estimation based upon said first distance and said second distance.

5. The system of claim 3, further comprising:

a controller coupled to said speed sensor and said second controller, said controller being configured to determine said first distance of said rail vehicle along the route based on said speed of the rail vehicle prior to said location along the route.

6. The system of claim 5, wherein said controller is coupled to said position determination device, said controller is configured to convert said measured position of said rail vehicle into said second distance of said rail vehicle along the route based on a memory of said controller for storing said second distance of said rail vehicle along the route based on said measured position.

7. The system of claim 6, wherein:

said position determination device is configured to transmit an uncertainty signal to said second controller, said uncertainty signal being indicative of a level of uncertainty in said measured position of said rail vehicle;

said speed sensor is configured to transmit an uncertainty signal to said controller, said uncertainty signal being subsequently re-transmitted to said second controller, said uncertainty signal being indicative of a level of uncertainty in the measured speed of the train.

8. The system of claim 7, wherein during a first time period when said position determination device provides said measured position of said rail vehicle, said second controller is configured to determine said quality of distance estimation based on at least one of said first distance, said second distance and said uncertainty signal.

9. The system of claim 8, wherein said second controller includes a memory, said memory being configured to store a plurality of prior distance estimations and a respective plurality of prior quality values for a plurality of previous locations from said location along the route, during said first time period said second controller is configured to determine said quality of distance estimation based on said first distance, said second distance, said uncertainty signal and said plurality of prior quality values.

10. The system of claim 9, wherein said position determination device is at least one global positioning satellite (GPS) device configured to communicate with a plurality of global positioning satellites.

11. The system of claim 10, wherein said distance estimation of said rail vehicle at said location along the route is based on one of a sum and difference of said quality of said distance estimation and said second distance.

12. The system of claim 11, wherein said second controller is configured to receive said first distance from said controller on a continuous time interval basis, said second controller is configured to receive said second distance from said controller on a diluted time interval basis, said second controller is configured to dynamically determine a correction to said first distance based on said second distance provided at said diluted time interval, said correction being based on said quality of said distance estimation.

13. The system of claim 9, wherein during a second time period when said position determination device ceases to measure said position of the rail vehicle, said second controller is configured to determine said quality of distance estimation based on a prior quality value before said position determination device ceased to provide said measured position, and a constant based on an uncertainty in said speed of the rail vehicle.

14. The system of claim 13, wherein during said second time period when said position determination device ceases to measure said position of the rail vehicle, said quality increases;

during said second time period when said position determination device begins to remeasure said position of the rail vehicle, said second controller is configured to determine a decrease in the quality of the distance estimation.

15. The system of claim 9, wherein said controller is configured to compare said first position and said second position to determine a precision of said second position relative to said first position, during a second time period when said controller determines that the precision falls below a threshold level for a threshold period of time, said second controller is configured to determine said quality of distance estimation based on a prior quality value prior to said threshold period of time, and a constant based on an uncertainty in said speed of the rail vehicle.

16. The system of claim 9, wherein said controller is switchable to an automatic mode, said controller in said automatic mode is configured to determine an initial parameter of said rail vehicle for each location along the route prior to the rail vehicle commencing a trip along the route.

17. The system of claim 16, wherein said controller in said automatic mode is configured to utilize said distance estimation and said quality of the distance estimation to adjust said initial parameter of the rail vehicle to a modified parameter for an upcoming location along the route.

18. The system of claim 17, wherein said parameter is the speed of the rail vehicle;

said distance estimation and said quality of the distance estimation are utilized to adjust said initial speed parameter of the rail vehicle to said modified speed parameter at said upcoming location of the rail vehicle, to comply with a speed restriction at said upcoming location along the route.

19. The system of claim 16, wherein said controller is switchable from said automatic mode to a manual mode in which a rail vehicle operator determines the initial parameter of the rail vehicle at each location along the route, said controller is configured to switch from said automatic mode to said manual mode upon said quality being outside a predetermined acceptable range stored in the memory of the controller

20. A system for determining a quality of a location estimation of a powered system at a location, said system comprising:

a speed sensor configured to determine a speed of said powered system at said location;

a position determination device configured to provide a measured position of said powered system; and

a second controller configured to determine said quality of the location estimation during a first time period when said position determination device provides said measured position of the powered system, said quality based on at least one of an uncertainty in said position of said powered system and an uncertainty in the speed of said powered system.

21. The system of claim 20, wherein said powered system is a rail vehicle at a location along a route;

said location estimation is a distance estimation of the rail vehicle along the route, and wherein;

said speed sensor is configured to determine a speed of said rail vehicle at said location along said route;

said position determination device is configured to provide a measured position of said rail vehicle; and

said second controller is configured to determine said quality of the distance estimation during a first time period when said position determination device provides said measured position of the rail vehicle, said quality based on at least one of an uncertainty in said position of said rail vehicle and an uncertainty in the speed of said rail vehicle.

22. The system of claim 21, wherein said position determination device is configured to transmit a position uncertainty signal to said second controller, said speed sensor is configured to transmit a speed uncertainty signal to said second controller, said position uncertainty signal and said speed uncertainty signal being indicative of said respective uncertainty in said position and said uncertainty in the speed of the rail vehicle.

23. The system of claim 22, wherein said second controller is configured to determine said distance estimation based upon a first distance of said rail vehicle along the route based on said rail vehicle speed, a second distance of said rail vehicle along the route based on said position of said rail vehicle, and said quality of the distance estimation.

24. The system of claim 23, wherein during a second time period when said position determination device ceases to provide said measured position of the rail vehicle, said quality is based on said uncertainty in the speed of the rail vehicle.

25. A method for determining a quality of a location estimation of a powered system at a location, said method comprising:

measuring a speed of the powered system at the location;

measuring a position of the powered system; and

determining the location estimation of the powered system and the quality of the location estimation, based upon a first location of the powered system based on the speed, and a second location of the powered system based on the measured position of the powered system.