Pilot vehicle which is useful for monitoring hazardous conditions on railroad tracks

• US 5,786,750 A
• Filed: 02/21/1997
• Issued: 07/28/1998
• Est. Priority Date: 05/10/1996
• Status: Expired due to Fees

• Current Assignee: The United States of America As Represented By The Secretary of Agriculture
• Original Assignee: the united states of america as represented by the secretary of the navy
• Inventors: Cooper, Guy F.
• Primary Examiner(s): Hofsass, Jeffery
• Assistant Examiner(s): GOINS, DAVETTA WOODS
• Application Number:
  US08/804,348
• Time in Patent Office: 522 Days
• Field of Search: 340/425.5, 340/539, 340/566, 340/938, 246/166, 246/167 R, 246/166.1, 246/121, 364/426.02, 180/167, 73/636
• US Class Current: 340/425.5
• CPC Class Codes: B61L 23/041 Obstacle detection
• CPC Class Codes: B61L 23/044 Broken rails

Abstract

A self-propelled remotely controlled pilot vehicle adapted for use on raiad tracks to monitor hazardous conditions and obstacles on the railroad tracks. The pilot vehicle precedes a train along the railroad tracks at a distance which will allow the train to come to a complete stop in the event the pilot vehicle encounters a hazardous condition on the track. The pilot vehicle is equipped with a sensor array which measures a variety of different parameters such as the presence of noxious gases, moisture in the atmosphere, breakage in one or both rails of the track and orientation with respect to the force of gravity as well as the yaw, pitch and roll attitude of the tracks upon which the pilot vehicle is riding. The pilot vehicle is also equipped with a television camera which provides a visual image of the railroad track ahead of the pilot vehicle to the engineer of the train. An infrared camera which is mounted on the front of the pilot vehicle generates an infrared image of the tracks. Information gathered by the pilot vehicle'"'"'s sensor array is supplied to a computer on board the pilot vehicle and is also transmitted to the train to enable the engineer to be apprised of conditions existing on the tracks ahead of the train in order to have time to react to dangerous situations on the railroad tracks.

Claims

1. A pilot vehicle for surveying railway tracks ahead of a train, said pilot vehicle traveling along a pair of rails of said railway tracks ahead of said train, said pilot vehicle comprising:

a frame;

drive means for propelling said pilot vehicle along said railway tracks;

processing means for receiving position information and control signals transmitted by said train, said processing means processing said position information and control signals to determine a safe distance said pilot vehicle is to be disposed ahead of said train;

drive control means operatively connected to said processing means and said drive means for maintaining said pilot vehicle at said safe distance ahead of said train;

first and second data wheels rotatably mounted on said pilot vehicle, said first and second data wheels engaging said railway tracks upon which said pilot vehicle is traveling, said first and second data wheels generating V1 and V2 electrical signals representative of the velocity of said data wheels as said pilot vehicle travels said railway tracks;

a magnetic compass mounted on said pilot vehicle, said magnetic compass generating a θ

_N electrical signal representative of a direction for said pilot vehicle as said pilot vehicle travels said railway tracks;

latitude location means mounted on said pilot vehicle, said latitude location means generating a ψ

_L electrical signal representative of degrees latitude of said pilot vehicle as said pilot vehicle travels said railway tracks;

a vertical rate gyro mounted on said pilot vehicle, said vertical rate gyro generating a θ

^C electrical signal representative of a pitch rate for said pilot vehicle as said pilot vehicle travels said railway tracks;

a three axis accelerometer mounted on said pilot vehicle, said pilot vehicle generating a^c'"'"'_xtot, a^c'"'"'_ytot and a^c'"'"'_ztot electrical signals representative of x, y and z components of acceleration exerted upon said pilot vehicle whenever said pilot vehicle accelerates along said railway tracks;

rail height sensing means positioned on said pilot vehicle to measure a height of said frame of said pilot vehicle above the top of the rails of said railway tracks, said rail height sensing means generating Δ

h^c_z1, Δ

h^c_z2, Δ

h^c_z3, and Δ

h^c_z4 electrical signals representative of the height of said frame of said pilot vehicle above the top of the rails of said railway tracks;

said processing means receiving and then processing said V1 and V2 electrical signals, said θ

_N electrical signal, said ψ

_L electrical signal, said θ

^C electrical signal, said ^c'"'"'_xtot, a^c'"'"'_ytot and a^c'"'"'_ztot electrical signals and said Δ

h^c_z1, Δ

h^c_z2, Δ

h^c_z3, and Δ

h^c_z4 electrical signals to provide a three by three direction cosine matrix representative of an azimuth heading for the rails of said railway tracks in a predetermined direction;

said processing means comparing said three by three direction cosine matrix with a previously recorded three by three direction cosine matrix for the rails of said railway tracks to locate changes in track orientation and determine when there is damage to the rails of said railway tracks.

2. The pilot vehicle of claim 1 wherein said processing means comprises a digital computer.

3. The pilot vehicle of claim 1 wherein said latitude locating means comprises a global positioning system.

4. The pilot vehicle of claim 1 further comprising a track gauge module coupled to said processing means, said track gauge module generating a d_g electrical signal representative of a track gauge for the rails of said railway tracks, said track gauge module providing said d_g electrical signal to said processing means for use by said processing means when said processing means generates said three by three direction cosine matrix.

5. The pilot vehicle of claim 1 wherein said track gauge for the rails of said railway track is a standard American gauge of approximately 4 feet 81/2 inches.

6. The pilot vehicle of claim 1 further comprising braking means coupled to said processing means to receive a braking signal from said processing means, said braking means, responsive to said braking signal, bringing said pilot vehicle to an immediate stop.

7. The pilot vehicle of claim 6 wherein said braking means comprises a pair of reaction jet stopping systems, each of said reaction jet stopping systems expelling a compressed gas into the atmosphere to bring said pilot vehicle to said immediate stop, a first of said pair of reaction jet stopping systems being pivotally mounted on one side of said pilot vehicle and a second of said pair of reaction jet stopping systems being pivotally mounted on an opposite side of said pilot vehicle.

8. The pilot vehicle of claim 7 wherein each of said pair of reaction jet stopping systems comprises:

a source of said compressed gas;

a normally closed solenoid valve having an inlet port connected to said source of compressed gas, an electrical activation port connected to said processing means to receive said braking signal and an outlet port;

a normally closed air activated valve having an inlet port connected to said source of compressed gas, an air activation port connected to the outlet port of said normally closed solenoid valve and an outlet port; and

a nozzle having a plenum, the plenum of said nozzle having a swivel fitting affixed thereto, said swivel fitting being pivotally coupled to the outlet port of said air activated valve to allow for rotational movement of said nozzle;

said normally closed solenoid valve being opened by said braking signal to allow said compressed air to pass through said normally closed solenoid valve to the air activation port of said normally closed air activated valve activating said normally closed air activated valve;

said normally closed air activated valve when activated allowing said compressed air to pass through said normally closed air activated valve and said plenum to said nozzle;

said nozzle expelling said compressed air to generate a rearward braking force opposing a forward direction of movement of said pilot vehicle.

9. A pilot vehicle for surveying railway tracks ahead of a train, said pilot vehicle traveling along a pair of rails of said railway tracks ahead of said train, said pilot vehicle comprising:

a frame;

drive means for propelling said pilot vehicle along said railway tracks;

a digital computer for receiving position information and control signals transmitted by said train, said processing means processing said position information and control signals to determine a safe distance said pilot vehicle is to be disposed ahead of said train;

drive control means operatively connected to said processing means and said drive means for maintaining said pilot vehicle at said safe distance ahead of said train;

first and second data wheels rotatably mounted on said pilot vehicle, said first and second data wheels engaging said railway tracks upon which said pilot vehicle is traveling, said first and second data wheels generating V1 and V2 electrical signals representative of the velocity of said data wheels as said pilot vehicle travels said railway tracks;

a magnetic compass mounted on said pilot vehicle, said magnetic compass generating a θ

_N electrical signal representative of a direction for said pilot vehicle as said pilot vehicle travels said railway tracks;

a global positioning system mounted on said pilot vehicle, said global positioning system generating a ψ

_L electrical signal representative of degrees latitude of said pilot vehicle as said pilot vehicle travels said railway tracks;

a vertical rate gyro mounted on said pilot vehicle, said vertical rate gyro generating a θ

^C electrical signal representative of a pitch rate for said pilot vehicle as said pilot vehicle travels said railway tracks;

a three axis accelerometer mounted on said pilot vehicle, said pilot vehicle generating a ^c'"'"'_xtot, a^c'"'"'_ytot and a^c'"'"'_ztot electrical signals representative of x, y and z components of acceleration exerted upon said pilot vehicle whenever said pilot vehicle accelerates along said railway tracks;

rail height sensing means positioned on said pilot vehicle to measure a height of said frame of said pilot vehicle above the top of the rails of said railway tracks, said rail height sensing means generating Δ

h^c_z1, Δ

h^c_z2, Δ

h^c_z3, and Δ

h^c_z4 electrical signals representative of the height of said frame of said pilot vehicle above the top of the rails of said railway tracks;

a track gauge module located on said pilot vehicle, said track gauge module generating a d_g electrical signal representative of a track gauge for the rails of said railway tracks;

said digital computer being connected to said first and second data wheels, said magnetic compass, said global positioning system, said vertical rate gyro, said three axis accelerometer, said rail height sensing means and said track gauge module to receive and then process said V1 and V2 electrical signals, said θ

_N electrical signal, said ψ

_L electrical signal, said θ

^C electrical signal, said ^c'"'"'_xtot, a^c'"'"'_ytot and a^c'"'"'_ztot electrical signals, said Δ

h^c_z1, Δ

h^c_z2, Δ

h^c_z3, and Δ

h^c_z4 electrical signals and said d_g electrical signal to provide a three by three direction cosine matrix representative of an azimuth heading for the rails of said railway tracks in a predetermined direction;

said digital computer comparing said three by three direction cosine matrix with a previously recorded three by three direction cosine matrix for the rails of said railway tracks to locate changes in track orientation and determine when there is damage to the rails of said railway tracks; and

braking means connected to said digital computer to receive a braking signal from said digital computer, said braking means, responsive to said braking signal, bringing said pilot vehicle to an immediate stop;

said bracking means including a pair of reaction jet stopping systems, each of said reaction jet stopping systems expelling a compressed gas into the atmosphere to bring said pilot vehicle to said immediate stop, a first of said pair of reaction jet stopping systems being pivotally mounted on one side of said pilot vehicle and a second of said pair of reaction jet stopping systems being pivotally mounted on an opposite side of said pilot vehicle.

10. The pilot vehicle of claim 9 wherein said track gauge for the rails of said railway tracks is a standard American gauge of approximately 4 feet 81/2 inches.

11. The pilot vehicle of claim 9 wherein each of said pair of reaction jet stopping systems comprises:

a source of said compressed gas;

a normally closed solenoid valve having an inlet port connected to said source of compressed gas, an electrical activation port connected to said digital computer to receive said braking signal and an outlet port;

a normally closed air activated valve having an inlet port connected to said source of compressed gas, an air activation port connected to the outlet port of said normally closed solenoid valve and an outlet port; and

a nozzle having a plenum, the plenum of said nozzle having a swivel fitting affixed thereto, said swivel fitting being pivotally coupled to the outlet port of said air activated valve to allow for rotational movement of said nozzle;

said normally closed solenoid valve being opened by said braking signal to allow said compressed air to pass through said normally closed solenoid valve to the air activation port of said normally closed air activated valve activating said normally closed air activated valve;

said normally closed air activated valve when activated allowing said compressed air to pass through said normally closed air activated valve and said plenum to said nozzle;

said nozzle expelling said compressed air to generate a rearward braking force opposing a forward direction of movement of said pilot vehicle.

12. The pilot vehicle of claim 9 wherein said rail height sensing means comprises first, second, third and fourth rail height sensors, one of said first, second, third and fourth rail height sensors being positioned at each corner of said frame of said pilot vehicle, each of said first, second, third and fourth rail height sensors including:

a height indicating member which has one end thereof riding on the top of one of said pair of rail of said railway tracks, said height indicating member being pivotally attached by a pivot assembly to an underside of said frame of said said pilot vehicle; and

a linear potentiometer pivotally attached by a pivot assembly to the underside of said frame of said pilot vehicle, said linear potentiometer having a rod which extends therefrom and which is attached to said height indicating member, said linear potentiometer being connected to said digital computer.

13. The pilot vehicle of claim 9 wherein said rail height sensing means comprises first, second, third and fourth rail height sensors, one of said first, second, third and fourth rail height sensors being positioned at each corner of said frame of said pilot vehicle, each of said first, second, third and fourth rail height sensors including:

a laser mounted on an underside of said frame of pilot said pilot vehicle, laser generating a pulsed beam of laser energy said pulsed beam of laser energy being directed toward the top of one of said pair of rails of said railway tracks, a portion of said pulse beam of laser energy being reflected from the top of the one of said pair of rails; and

a sensing element attached to the underside of said frame of said pilot vehicle adjacent said laser, said sensing element receiving the portion of said pulse beam of laser energy, said sensing element being connected to said digital computer.

14. A pilot vehicle for surveying railway tracks ahead of a train, said pilot vehicle traveling along a pair of rails of said railway tracks ahead of said train, said pilot vehicle comprising:

a frame;

drive means for propelling said pilot vehicle along said railway tracks;

a digital computer for receiving position information and control signals transmitted by said train, said processing means processing said position information and control signals to determine a safe distance said pilot vehicle is to be disposed ahead of said train;

drive control means operatively connected to said processing means and said drive means for maintaining said pilot vehicle at said safe distance ahead of said train;

first and second data wheels rotatably mounted on said pilot vehicle, said first and second data wheels engaging said railway tracks upon which said pilot vehicle is traveling, said first and second data wheels generating V1 and V2 electrical signals representative of the velocity of said data wheels as said pilot vehicle travels said railway tracks;

a magnetic compass mounted on said pilot vehicle, said magnetic compass generating a θ

_N electrical signal representative of a direction for said pilot vehicle as said pilot vehicle travels said railway tracks;

a global positioning system mounted on said pilot vehicle, said global positioning system generating a ψ

_L electrical signal representative of degrees latitude of said pilot vehicle as said pilot vehicle travels said railway tracks;

a vertical rate gyro mounted on said pilot vehicle, said vertical rate gyro generating a θ

^C electrical signal representative of a pitch rate for said pilot vehicle as said pilot vehicle travels said railway tracks;

a three axis accelerometer mounted on said pilot vehicle, said pilot vehicle generating a ^c'"'"'_xtot, a^c'"'"'_ytot and a^c'"'"'_ztot electrical signals representative of x, y and z components of acceleration exerted upon said pilot vehicle whenever said pilot vehicle accelerates along said railway tracks;

rail height sensing means positioned on said pilot vehicle to measure a height of said frame of said pilot vehicle above the top of the rails of said railway tracks, said rail height sensing means generating Δ

h^c_z1, Δ

h^c_z2, Δ

h^c_z3, and Δ

h^c_z4 electrical signals representative of the height of said frame of said pilot vehicle above the top of the rails of said railway tracks;

a track gauge module located on said pilot vehicle, said track gauge module generating a d_g electrical signal representative of a track gauge for the rails of said railway tracks;

said digital computer being connected to said first and second data wheels, said magnetic compass, said global positioning system, said vertical rate gyro, said three axis accelerometer, said rail height sensing means and said track gauge module to receive and then process said V1 and V2 electrical signals, said θ

_N electrical signal, said ψ

_L electrical signal, said θ

^C electrical signal, said ^c'"'"'_xtot, a^c'"'"'_ytot and a^c'"'"'_ztot electrical signals, said Δ

h^c_z1, Δ

h^c_z2, Δ

h^c_z3, and Δ

h^c_z4 electrical signals and said d_g electrical signal to provide a three by three direction cosine matrix representative of an azimuth heading for the rails of said railway tracks in a predetermined direction;

said digital computer comparing said three by three direction cosine matrix with a previously recorded three by three direction cosine matrix for the rails of said railway tracks to locate changes in track orientation and determine when there is damage to the rails of said railway tracks;

said digital computer generating a warning message signal whenever said digital computer determines damage has occurred to the rails of said railway tracks;

a transmitter/receiver module connected to said digital computer to receive said warning message signal from said digital computer;

said transmitter/receiver module having a modulator and an antenna, said modulator modulating a radio frequency signal responsive to said warning message signal, said antenna transmitting said radio frequency signal to said train;

braking means connected to said digital computer to receive a braking signal from said digital computer, said braking means, responsive to said braking signal, bringing said pilot vehicle to an immediate stop;

said bracking means including a pair of reaction jet stopping systems, each of said reaction jet stopping systems expelling a compressed gas into the atmosphere to bring said pilot vehicle to said immediate stop, a first of said pair of reaction jet stopping systems being pivotally mounted on one side of said pilot vehicle and a second of said pair of reaction jet stopping systems being pivotally mounted on an opposite side of said pilot vehicle.

15. The pilot vehicle of claim 14 wherein each of said pair of reaction jet stopping systems comprises:

a source of said compressed gas;

a normally closed solenoid valve having an inlet port connected to said source of compressed gas, an electrical activation port connected to said digital computer to receive said braking signal and an outlet port;

a normally closed air activated valve having an inlet port connected to said source of compressed gas, an air activation port connected to the outlet port of said normally closed solenoid valve and an outlet port; and

a nozzle having a plenum, the plenum of said nozzle having a swivel fitting affixed thereto, said swivel fitting being pivotally coupled to the outlet port of said air activated valve to allow for rotational movement of said nozzle;

said normally closed solenoid valve being opened by said braking signal to allow said compressed air to pass through said normally closed solenoid valve to the air activation port of said normally closed air activated valve activating said normally closed air activated valve;

said normally closed air activated valve when activated allowing said compressed air to pass through said normally closed air activated valve and said plenum to said nozzle;

said nozzle expelling said compressed air to generate a rearward braking force opposing a forward direction of movement of said pilot vehicle.

16. The pilot vehicle of claim 14 wherein said rail height sensing means comprises first, second, third and fourth rail height sensors, one of said first, second, third and fourth rail height sensors being positioned at each corner of said frame of said pilot vehicle, each of said first, second, third and fourth rail height sensors including:

a height indicating member which has one end thereof riding on the top of one of said pair of rail of said railway tracks, said height indicating member being pivotally attached by a pivot assembly to an underside of said frame of said said pilot vehicle; and

a linear potentiometer pivotally attached by a pivot assembly to the underside of said frame of said pilot vehicle, said linear potentiometer having a rod which extends therefrom and which is attached to said height indicating member, said linear potentiometer being connected to said digital computer.

17. The pilot vehicle of claim 14 wherein said rail height sensing means comprises first, second, third and fourth rail height sensors, one of said first, second, third and fourth rail height sensors being positioned at each corner of said frame of said pilot vehicle, each of said first, second, third and fourth rail height sensors including:

a laser mounted on an underside of said frame of pilot said pilot vehicle, laser generating a pulsed beam of laser energy said pulsed beam of laser energy being directed toward the top of one of said pair of rails of said railway tracks, a portion of said pulse beam of laser energy being reflected from the top of the one of said pair of rails; and

a sensing element attached to the underside of said frame of said pilot vehicle adjacent said laser, said sensing element receiving the portion of said pulse beam of laser energy, said sensing element being connected to said digital computer.

18. The pilot vehicle of claim 14 wherein said track gauge for the rails of said railway tracks is a standard American gauge of approximately 4 feet 81/2 inches.

19. The pilot vehicle of claim 14 further comprising a video camera mounted on said pilot vehicle at a front end of said pilot vehicle, said video camera monitoring a visual scene presented to said pilot vehicle as said pilot vehicle travels along the rails of said railway tracks.

20. The pilot vehicle of claim 14 further comprising an infrared camera mounted on said pilot vehicle at a front end of said pilot vehicle, said infrared camera monitoring an infrared scene presented to said pilot vehicle as said pilot vehicle travels along the rails of said railway tracks.