Systems and methods for monitoring moving surfaces using light signals

• US 7,734,435 B2
• Filed: 08/15/2007
• Issued: 06/08/2010
• Est. Priority Date: 08/15/2006
• Status: Active Grant

• Current Assignee: Cognitive Vision, Inc.
• Original Assignee: Cognitive Vision, Inc.
• Inventors: Schumacher, Raymond Joseph, Thomas, John Gordon, Neild, Peter James
• Primary Examiner(s): Wachsman; Hal D
• Application Number:
  US11/839,173
• Publication Number:
  US 20080215270A1
• Time in Patent Office: 1,028 Days
• Field of Search: 702/70, 702/40, 702/66, 702/74
• US Class Current: 702/70
• CPC Class Codes: G01P 3/486 delivered by photo-electric detectors
• CPC Class Codes: G01P 3/68 using optical means, i.e. using infrared, visible, or ultraviolet light G01P3/80 takes precedence ; by reflection of waves G01S17/58

Abstract

This present specification provides, amongst other things, an electro-optical monitoring system for obtaining a once-per revolution signal based on the surface reflection of a rotating device that mandates non-contacting sensor input in potentially hostile environments. The system can use optical and electronic sections to illuminate and detect surface reflections from the rotating surface using existing mounting locations on the periphery of the machine to be measured. The electronic portion is configured to determine a unique mark as the once-per-revolution marker or allow an attending operator to assign a specific marker based on the observed reflected pattern. The optical portion consists of a light source, receiver, and optics that allow for focused and directed light paths.

Claims

1. A monitoring system for a moving surface comprising:

an emitter for emitting a plurality of light signals onto said moving surface;

a collector for receiving a plurality of reflected representations of said light signals;

electronics connected to said collector and configured to combine said reflected representations into a waveform;

said electronics further configured to derive and collect a plurality of sample points from said waveform;

said electronics further configured to derive a timing period from said plurality of sample points based on a unique artifact associated with a given waveform shape;

said electronics further configured to define a marker in said waveform based on said timing period and to generate an output signal that includes a representation of said marker.

2. The monitoring system of claim 1 wherein said emitter comprises a plurality of light emitting fiber-optic strands randomly dispersed in parallel to each other.

3. The monitoring system of claim 2 wherein said collector comprises a plurality of non-light emitting fiber-optic strands randomly dispersed in parallel to each other and in relation to said light emitting fiber-optic strands.

4. The monitoring system of claim 1 wherein said electronics comprise a microcomputer configuration including one or more central processing units, volatile memory, non-volatile memory, all interconnected by a bus to which a source respective to said emitter and said collector also connect.

5. The monitoring system of claim 1 wherein said moving surface is a gas turbine engine and said emitter and receiver are mounted within a bulkhead fitting attached within a bore of a chassis of said gas turbine engine.

6. The monitoring system of claim 1 wherein said emitter and said collector are connected to said electronics via a fiber optic cable.

7. The monitoring system of claim 1 wherein said electronics further comprise an interface for connecting an external device to receive said generated output signal.

8. The monitoring system of claim 1 wherein said moving surface is rotating.

9. The monitoring system of claim 1 wherein said electronics comprise a plurality of field programmable gate arrays.

10. The system of claim 1 wherein said artifact is a repeating extreme excursion within said sample points.

11. A method for monitoring a moving surface comprising:

emitting a plurality of light signals onto said moving surface;

receiving a plurality of reflected representations of said light signals;

combining said reflected representation into a waveform;

deriving a plurality of sample points from said waveform;

deriving a timing period from said plurality of sample points based on a unique artifact associated with a given waveform shape;

defining a marker in said waveform based on said timing period; and

,

generating an output signal that includes a representation of said marker.

12. The method of claim 11 wherein said emitting step is performed using a plurality of light emitting fiber-optic strands randomly dispersed in parallel to each other.

13. The method of claim 12 wherein said receiving step is performed using a plurality of non-light emitting fiber-optic strands randomly dispersed in parallel to each other and in relation to said light emitting fiber-optic strands.

14. The method of claim 11 further comprising sending said output signal to an external device.

15. The method of claim 11 wherein said moving surface is rotating.

16. The method of claim 11 wherein said artifact is a repeating extreme excursion within said sample points.