Space application of FBG sensors

FBG sensors for space applicationFiber Bragg grating sensors are highly useful fiber optic sensing devices that help carry out the monitoring of temperature and strain characteristics even during a nanosatellite mission. FBG sensors present highly attractive reliable fiber optic solutions for process monitoring in a spacecraft. Additionally, it is possible to install these fiber sensors in composite structures or attached on their surface for structural health monitoring during the entire life cycle of a satellite.

To be more precise, space application of fiber optic sensors requires the use of two fiber Bragg gratings to measure temperature and strain characteristics during one space mission. The main aim of the mission is the validation and demonstration of the suitability and reliability of fiber optic technologies when it comes to a small area with numerous restrictions in terms of mass and power consumption.

Despite the fact that FBG sensors offer great performance in various fields of application, especially in industry, engineering and science, however, the use of fiber sensors in space application is not so popular, although fiber optics are presented more than 30 years in space but typically applied to transmit data or to guide the light for illumination purposes.

Fiber sensors based on fiber Bragg grating technology have numerous benefits such as electromagnetic immunity, the possibility of multiplexing, and weight-saving by taking copper harness away. This is the reason why fiber sensing technology is perfect for the harsh space environment.

Also, FBG sensors are better than other optical fiber sensors because their optical response does not depend on the optical power of the light source the eventual loss of energy transmitted along with the optical fiber, and of the response of the photodetector, thus, the response of the fiber sensor is considered to be wavelength-coded.

The used FBG technology has been successfully tested and the tests presented the capability and reliability of fiber optic sensors based on fiber Bragg gratings in space environmental conditions. In spite of the high restrictions in terms of mass, volume, and power consumption, FBG sensors offer an optimal performance of all-optical fiber components after their 3 years’ application in the space environment.

Finally, during the whole space mission crucial attenuation proving the degradation of fiber optic components because of harsh environmental conditions (as well as radiation and vacuum conditions) has not been registered. Herewith, the used tunable laser system for telecommunications purposes also presented excellent results in the space environment. It is possible that these FBG sensors contribute to the creation of more complex sensor arrays with a more complex FBG interrogator unit that will enable better resolution and operation in a wider temperature range.

If you want to obtain a highly efficient sensing system, you should choose the Optromix company. Optromix is a manufacturer of innovative fiber optic products for the global market. The company provides the most technologically advanced fiber-optic solutions for monitoring worldwide. Optromix is a fast-growing vendor of fiber Bragg grating (FBG) products line such as fiber Bragg grating sensors, FBG interrogators and multiplexers, distributed acoustic sensing (DAS) systems, distributed temperature sensing (DTS) systems. If you are interested in FBG sensors and want to learn more, please contact us at info@optromix.com

FBG accelerometers measure acceleration and vibration on trains

FBG accelerometers for train monitoringNowadays train accidents often cause severe injuries and even cases of death. Nevertheless, researchers from China have designed new fiber optic sensors that allow measuring acceleration and vibration characteristics on trains. Additionally, this optical fiber technology can be used in a combination with artificial intelligence in order to prevent potential railway accidents and catastrophic train derailments.

To be more precise, the FBG accelerometers are able to monitor problems in the railway track or the train in real-time to detect defects before an accident happens. Such fiber optic devices identify frequencies more than double that of conventional optical fiber accelerometers, making them ideal for monitoring wheel-rail interactions. 

The principle of durable FBG sensors’ operation is based on the use of no moving parts, herein, the fiber accelerometers demonstrate good operation in the noisy as well as in high-voltage environmental conditions found in the railway field of application. Moreover, the researchers confirm that their novel FBG accelerometers can be applied in other vibration monitoring applications. For example, fiber optic applications include structural health monitoring for buildings and bridges and vibration measurements of aircraft wings.

It should be noted that the researchers have been developing condition-monitoring optical fiber systems for more than 15 years using an all-optical sensing network to continuously monitor crucial railway components. It is planned that these fiber optic sensing systems help change poor efficient traditional railway maintenance routines by predictive maintenance based on actual conditions. 

The developed FBG accelerometers demonstrate the following benefits that include:

  • immunity to electromagnetic interference;
  • long transmission distance;
  • no need for electricity.

But a need for FBG sensors for the measurement of various characteristics in railway systems still remain. Traditionally, fiber accelerometers are based on fiber Bragg gratings whose use is limited by 500 Hz vibrations. Therefore, such fiber optic technology was not suitable for the measurement of the wheel-rail interactions that are considered to be an important source of track wear.

Finally, the researchers have developed totally new FBG accelerometer based on a specific optical fiber (a polarization-maintaining photonic crystal fiber). It has been tested by installing the optical fiber device on an in-service train. Thus, the FBG accelerometer demonstrates a similar operation to the piezoelectric accelerometer, but it does not require expensive shielded fiber cables to take the effects of electromagnetic interference down.

If you want to obtain a highly efficient sensing system, you should choose the Optromix company. Optromix is a manufacturer of innovative fiber optic products for the global market. The company provides the most technologically advanced fiber-optic solutions for monitoring worldwide. Optromix is a fast-growing vendor of fiber Bragg grating (FBG) products line such as fiber Bragg grating sensors, FBG interrogators and multiplexers, distributed acoustic sensing (DAS) systems, distributed temperature sensing (DTS) systems. If you are interested in FBG sensors and want to learn more, please contact us at info@optromix.com

How does distributed acoustic sensing work?

DAS operationDistributed fiber optic sensing is considered to be an advanced technology that allows changing the principle of infrastructure management. The fiber optic technology converts optical fibers into thousands of sensors and controls tens of kilometers of an asset with a single FBG interrogator. Thus, optical fiber sensors are a highly cost-effective fiber optic solution that is used by numerous industries every year.

Herewith, Distributed Acoustic Sensing or DAS technology has a wider scope of potential fiber optic applications, both scientific (seismic, mechanical) and industrial (security, integrity, operation monitoring) because DAS detects vibrations along with the optical fiber. It should be noted that the detection and analysis of sound waves remains one of the most effective techniques for sensing information.

The principle of distributed acoustic sensing operation is based on the use of a fiber optic cord that is placed in an acoustic sensing housing that picks up sounds along the length of the cord. Therefore, DAS technology makes it possible to obtain a more detailed scan of hazardous or hard-to-reach places.

Moreover, the additional DAS benefit includes the possibility to identify the strain of the fiber optic cord to help prevent damages. The fields of DAS applications include the sensing disturbances around fracking operations underground that is possible to perform during and after the process to ensure safety. Also, distributed acoustic sensing can be applied to guide the fracking operation to the right underground deposits.

Generally, the DAS system is used to offer less disturbance to places applied for oil drilling and fracking. Nevertheless, DAS technology is ideally suited for the measurement of seismic events and control of fault lines with less of an equipment footprint and impact on the surrounding area.

Distributed acoustic sensing offers the following advantages that include:

  • High precision due to its linear response; 
  • Very high sensitivity; 
  • Great coverage, exceeding 70 km; 
  • The possibility of programming real-time applications directly on the device. 

Finally, the fields of DAS applications continue expanding. At the present time, it includes perimeter intrusion detection, third-party interference detection, power cable monitoring,  traffic monitoring (roads, railway, subway), seismic activity monitoring, subsea cable monitoring, asset integrity, oil, gas, and water pipelines.

Optromix is a DAS system manufacturer that provides top of the line distributed acoustic sensing systems suitable for monitoring of commerce networks. If you have any questions or would like to buy a DAS system, please contact us at info@optromix.com