Recent advances in materials science have resulted in a proliferation of flexible structures for high-performance civil,
mechanical, and aerospace applications. Large aspect-ratio aircraft wings, composite wind turbine blades, and
suspension bridges are all designed to meet critical performance targets while adapting to dynamic loading conditions.
By monitoring the distributed shape of a flexible component, fiber optic shape sensing technology has the potential to
provide valuable data during design, testing, and operation of these smart structures. This work presents a demonstration
of such an extended-range fiber optic shape sensing technology. Three-dimensional distributed shape and position
sensing is demonstrated over a 30m length using a monolithic silica fiber with multiple optical cores. A novel, helicallywound
geometry endows the fiber with the capability to convert distributed strain measurements, made using Optical
Frequency-Domain Reflectometry (OFDR), to a measurement of curvature, twist, and 3D shape along its entire length.
Laboratory testing of the extended-range shape sensing technology shows