FBG

WHAT IS FBG ?

In this context, FBG sensors are basically manufactured by causing refractive index modulation at a specified location within the fiber optical cable that is having 9 micrometers of core and 125 micrometers of clad diameter.

As a Hi-Tech product FBGs take over the place of the conventional sensors especially at the fields given below;

• FBGs can be embedded into composite materials and allow smart material production:
  FBGs can be used in new generation aerospace and air vehicles (such like; airplanes, unmanned air vehicles (UAV), wind turbines, drones, satellites and etc.) in order to track the trip quality and structural health of the devices.

• FBGs can be used in smart city organizations by simply assembling them into the various consantrated structures such as asphalt,concrete and cement:
  FBGs can be simply used in highways, bridges, railways as well as in gas and oil industry in order to track strain levels along the line and determine deformation/crack locations to prevent any possible danger.

FIELDS OF APPLICATION

• STRUCTURES: It provides cost effective solutions when applied to large scale structures such as Oil Platforms, Bridges, Mines, Dams, Tunnels.
• ENERGY: FBGs can be safely used in various energy fields such as Wind Turbines, Oil Wells, Pipelines, Nuclear Reactors and Generators. The reason is that FBGs are immune to electromagnetic fields and high radio frequency consisting fields.
• WIND TURBINES: It provides the structural health monitoring of the propellers, instant control and observation of the operating status.
• TRANSPORTATION: It is used for structural health monitoring in highways, bridges and tunnels to determine when maintenance is compulsory.
• NAVIGATE: FBG sensors in submarines and ships used for structural health, load and fatigue behavior monitoring at specific points in the structure.
• LABORATORY TESTS AND MEASUREMENTS: FBG sensors can be used in laboratory environments safely where various physical parameters are measured, espically in the mechanical testing stage for the following purposes.
• SAFETY AND SECURITY: It uses around the police station and at the border lines by placing them on the security wires.
• MEDICAL: Medical robotic arm, patient status tracking devices

ADVANTAGES

• Measuring at long distances
• Low setup cost
• A technology promises for sensors small in size, flexible and light weight
• Accurate test results
• Immunity to electro-magnetic field and radio frequency interferences
• Measuring various physical parameters simultaneously
• Getting measurement results from different points simultaneously
• Passive circuit element
• Applicability at diverse fields
• Realtime measuring opportunity

COMPOSITE

In literature, composite is defined as composition of two or more constituent materials which in turn results a material having greater properties as compares to base materials. FBG sensors started to be used in composite materials with the developing technology because of it’s unique properties which allows ones to monitor the inner events among the layers of the composite material. So that FBG sensors can be easily embedded into composite materials such as Carbon Fiber Reinforced Polymer (CFRP) and Glass Fiber Reinforced Polymer (GFRP). When FBG sensors embedded into the composite laminated, ones will be eligible to observe temporary and permanent changes as well as deformations within the composite material.

Especially in avionic and space applications, embeding FBGs into composite materials allows ones to have a proper structral health monitoring and testing system. Eventually, using FBG sensors in such fields allows to monitor the material integrity, deformation, health status and by that unnecessary maintenance, waste of time and money will be prevented. Use of avionic application areas.