Flashlamp degradation monitoring system and method

• US 9,970,971 B2
• Filed: 09/23/2014
• Issued: 05/15/2018
• Est. Priority Date: 09/23/2014
• Status: Active Grant

• Current Assignee: The Boeing Co.
• Original Assignee: The Boeing Co.
• Inventors: Jungwirth, Douglas R., Bouckaert, Anton M.
• Primary Examiner(s): Bloss, Stephanie
• Application Number:
  US14/494,145
• Publication Number:
  US 20160084896A1
• Time in Patent Office: 1,330 Days
• Field of Search: 702 66
• CPC Class Codes: G01J 1/42 using electric radiation detectors optical or mechanical part G01J1/04; by comparison with a reference light or electric value G01J1/10
• CPC Class Codes: G01J 2001/4238 Pulsed light
• CPC Class Codes: G01N 21/88 Investigating the presence of flaws or contamination
• CPC Class Codes: G01N 2201/088 Using a sensor fibre
• CPC Class Codes: G01R 17/00 Measuring arrangements involving comparison with a reference value, e.g. bridge
• CPC Class Codes: G01R 19/0046 characterised by a specific application or detail not covered by any other subgroup of G01R19/00
• CPC Class Codes: G01R 29/027 Indicating that a pulse characteristic is either above or below a predetermined value or within or beyond a predetermined range of values
• CPC Class Codes: G01R 31/245 Testing of gas discharge tubes

Abstract

A method for monitoring degradation of a flashlamp including triggering the flashlamp to produce a light pulse, monitoring at least one parameter as a function of time to obtain a pulse waveform of the light pulse, comparing the pulse waveform to at least one reference pulse waveform to determine a difference therebetween, and flagging an end-of-lamp-life condition when the difference exceeds a predetermined threshold.

Claims

1. A method for monitoring degradation of a flashlamp comprising:

triggering the flashlamp to create a plasma and produce a light pulse corresponding to the created plasma;

obtaining a plurality of values of a first parameter as a function of time during the produced light pulse to generate a pulse waveform of the produced light pulse;

retrieving a reference pulse waveform of a reference light pulse, the reference pulse waveform including a plurality of values of the first parameter as a function of time during the reference light pulse;

comparing the generated pulse waveform of the produced light pulse to at least the reference pulse waveform to determine a difference therebetween; and

flagging an end-of-lamp-life condition when the difference exceeds a predetermined threshold, wherein the flagging step comprises preventing firing of the flashlamp.

2. The method of claim 1 wherein the flashlamp comprises an ionizable gas sealed in an envelope.

3. The method of claim 2 wherein the ionizable gas comprises xenon.

4. The method of claim 2 wherein the triggering step comprises applying a voltage having a magnitude sufficient to initiate ionization of the ionizable gas.

5. The method of claim 1 wherein the obtaining step comprises electronically obtaining the first parameter.

6. The method of claim 5 wherein the first parameter is electric current.

7. The method of claim 5 wherein the first parameter is voltage.

8. The method of claim 1 wherein the obtaining step comprises optically obtaining the first parameter.

9. The method of claim 8 wherein the first parameter is light energy.

10. The method of claim 1 further comprising storing the pulse waveform.

11. The method of claim 1 wherein the reference pulse waveform comprises a pulse waveform from a previous light pulse.

12. The method of claim 1 wherein the comparing step comprises at least one of a cross-correlation analysis, a derivative analysis and a linear approximation analysis.

13. The method of claim 1 wherein the predetermined threshold is of a magnitude sufficient to allow normal pulse waveform-to-pulse waveform variation without flagging the end-of-lamp-life condition.

14. The method of claim 1 wherein the flagging step comprises providing at least one of a visual indication and an audible indication of the end-of-lamp-life condition.

15. The method of claim 1 further comprising:

charging one or more capacitors;

discharging the one or more capacitors to pass a current when the trigger initiates ionization of a gas within the flashlamp, thereby producing a high-current pulse sufficient to create the plasma and produce the light pulse corresponding to the created plasma.

16. The method of claim 1 wherein the produced light pulse has a duration ranging from about 0.001 seconds to about 0.005 seconds.

17. The method of claim 1 wherein the first parameter is an electric current, a voltage, or a magnitude of light.

18. A flashlamp degradation monitoring system comprising:

a flashlamp comprising an envelope housing an ionizable gas and opposed electrodes;

a power supply electrically coupled to the electrodes;

a trigger positioned to initiate ionization of the ionizable gas to create a plasma and produce a light pulse corresponding to the created plasma;

a sensor positioned to obtain a plurality of values of a first parameter as a function of time during the produced light pulse to generate a pulse waveform of the produced light pulse; and

a computer in communication with the sensor, wherein the computer is configured to retrieve a reference pulse waveform of a reference light pulse, the reference pulse waveform including a plurality of values of the first parameter as a function of time during the reference light pulse, to compare the generated pulse waveform with at least the reference pulse waveform to determine a difference therebetween, and to flag an end-of-lamp-life condition when the difference exceeds a predetermined threshold.

19. The system of claim 18 wherein the sensor is current sensor or a voltage sensor.

20. The system of claim 18 wherein the sensor is an optical detector.

21. The system of claim 20 further comprising a lens positioned to focus the light pulse onto the optical detector.

22. The method of claim 18 wherein the first parameter is an electric current, a voltage, or a magnitude of light.