Fiber optic shape sensing system using anchoring points

摘要

Disclosed herein is a method for sensing one or more selected parameters related to a structure of interest, for example, the shape of an isolated structure. A cable is attached to the structure of interest at one or more attachment points. The cable contains one or more optical fibers. One or more light signals are transmitted into the one or more optical fibers and then detected to form a data set. The data set is compared with information known about the one or more attachment points to determine error values. The error values are then combined with the data set to determine the selected parameters associated with the structure.

主权项

1. A method for monitoring a downhole tubular defining a tubular axis comprising:
transmitting one or more light signals into one or more optical fibers coupled to the downhole tubular at one or more attachment points, the one or more optical fibers extending substantially linearly along the downhole tubular; detecting and processing, through a central processor, the one or more light signals to form a data set; determine an induced torsional value of the one or more optical fibers at one of the one or more attachment points; comparing, through the central processor, the data set with predetermined location data describing the one or more attachment points to estimate one or more error values associated with the induced torsional value of the one or more optical fibers at the one of the one or more attachment points; and combining the data set and the one or more error values to determine one or more selected parameters of the downhole tubular.