Apa itu sensor serat optik? Distributed fiber optic sensing and grating sensing-INNO

Apa itu penginderaan serat optik?

Teknologi penginderaan serat optik mengumpulkan data regangan dan suhu terkait struktur untuk memvalidasi struktur dan model termal, memastikan integritas struktural, dan meningkatkan efisiensi operasional.
Penginderaan serat optik dan teknologi tradisional

Pengukur regangan dan termokopel telah lama menjadi standar untuk mengukur regangan dan suhu selama proses pengujian. Padahal teknologi tersebut sudah ada selama puluhan tahun, mereka tidak selalu mampu menguji dan memantau inovasi masa kini secara efektif. Keterbatasan teknologi lama tidak berhubungan dengan akurasi, namun terutama pada tingkat wawasan yang diberikan oleh data. Pengukur regangan dan termokopel hanya memberikan titik informasi, while certain types of fiber optic sensors can provide spatially continuous data along the entire length of the fiber optic. Jadi, engineers can measure the strain field and temperature distribution on the structure to better understand the behavior of components under different conditions. Point sensors only allow engineers to monitor key points, while distributed (spatial continuous data) sensors can measure key points and what happens between them. This insight is very valuable when designing new composite materials. Sebagai tambahan, fiber optic sensors can be embedded in materials to better understand the internal behavior of composite components and structures.

Fundamentals of Fiber Optic Sensing

The inherent fiber optic sensing technology, in which the fiber optic cable itself is a sensor. In the division of internal sensors, there are generally three generations of technologies: point fiber Bragg grating (FBG) sensor berbasis, penyebaran, and spatially continuous FBG. Scattering technology adopts fully distributed measurement, while FBG technology can have a small number of sensing points or complete distribution, depending on how the system interprets the signal from the sensing elements.

FBG acts as a tiny mirror and is manufactured into the core of optical fibers. When light propagates along the fiber optic, each grating reflects a portion of the signal back into the system. The system recognizes the changes in the return signal and interprets this information to provide accurate strain and temperature measurements. Most FBG based systems have some sensing points along each fiber. Although this multiplexing function is a major advancement in traditional technology, it still cannot provide the sensor density required for monitoring between critical areas. Some advantages of point FBG sensors include accuracy, the ability to perform dynamic testing, dan akuisisi data berkecepatan tinggi.

Scattering technology does not use FBG at all, but relies on defects in optical cables to obtain readings. Sekarang, three different types of scattering techniques are used in sensing systems, each with different functions. Secara umum, scattering based fiber optic sensing systems benefit from distributed data and long sensing lengths. Namun, they have low data fidelity, very slow data acquisition rates on the order of a few minutes, and are susceptible to vibration limitations when performing static operations.