Measurement uncertainty of 7-core multicore fiber shape sensors

Abstract

Fiber optic shape sensing is innovative technology, which enables distributed structural health monitoring, providing real-time feedback on shape and position, based on smart sensors arrays, which consists of optical fiber bundles or multicore fibers with embedded strain sensors. This paper describes a numerical analysis carried out to identify the effects of uncertainty in strain measurement and core position on the accuracy of fiber optic shape sensors, taking into consideration one of the most utilized geometry for fiber optic sensing applications, the seven-core Multicore Fiber, and distinct values of core spacings (distance between outer cores and sensor axis). The Monte Carlo Method was employed to simulate the real measurement process and one million of iterations were performed for each simulation with the aim of defining the laws of uncertainty propagation. The results of this study demonstrate the influence of core position uncertainty, strain measurement resolution and core spacing on optical shape sensors accuracy and can support the design of new sensors, predicting the achievable performance.