Patent ID: 7113660

Claim:
A method for detecting structural damage to a filament wound composite pressure vessel, the method comprising: winding an optical fiber on and adhering it to an exterior surface of the composite pressure vessel; injecting first and second light signals into an end of the optical fiber at different times; detecting the first and second light signals at an end of the optical fiber; comparing the first and second light signals with each other; injecting a light signal into a first end of the optical fiber; reflecting the light signal from an opposite second end of the optical fiber; and, detecting the reflected light signal at the first end of the optical fiber; providing a two-dimensional map of the optical fiber on the exterior surface of the composite pressure vessel; detecting a reflected light signal corresponding to a discontinuity in the optical fiber; measuring the amount of time taken by the reflected light signal to travel from the first end of the fiber to the discontinuity and back to the first end; computing the distance of the discontinuity from the first end of the optical fiber from the time taken; and, locating the discontinuity on the map.