Versions of Fiber-Optic Sensors for Monitoring the Technical Condition of Aircraft Structures

Abstract

It is necessary to monitor the technical condition of various equipment due to the increased requirements for the safe operation of complex technical objects, such as bridges, structures, aircraft, cars and others. Monitoring systems based on the use of fiber-optic sensors measuring various physical quantities (temperature, deformation, pressure, vibration, etc.) are increasingly used for these purposes, since they have significant advantages over electrical sensors. The aim of the study is to compare the various options for the implementation of fiber-optic strain sensors to monitor the stress-strain state of the monitored object. A theoretical and experimental comparison of three types of fiber-optic sensors was carried out: on a mechanical fastener, sensors glued to the surface of a monitored design, and sensors embedded in a polymeric composite material at the stage of its manufacture. The requirements for the elements of the onboard systems of the aircraft according to the document “Environmental conditions and test procedures for airborne equipment QR-160D” are selected as comparison parameters. To assess the characteristics of various types of fiber-optic strain sensors, comparative bench mechanical and environmental tests were carried out. According to the test results, it was concluded that each type of sensor has its own advantages and disadvantages in comparison with each other, and in general, each of them can be used to create new standard systems for structural health monitoring of various units and structures of the aircraft (SHM systems). Also, the article proposed a new method of gluing a fiber-optic sensor to a controlled structure. This method - the use of specialized equipment, providing convenience and stability of gluing.

The feasibility of motion sensor-based smart RFID system in improving the power saving

“…Several phenomena are exploited in detecting motion such as the optical, microwave, and acoustic (Khan et al, 2019;Micko, 2008;Lvov et al, 2018;Bakhsheshi et al, 2019;Moghavvemi and Seng, 2004). One of the very commonly used sensors is the pyroelectric infrared-based motion detector (PIR sensor), which is a passive sensor, its technology mainly based on detecting the heat energy emitted from the moving object in form of radiations, as this heat energy varies following the moving object' temperature.…”

Non-Invasive Acoustic Monitoring of Gas Turbine Units by Fiber Optic Sensors

“…At present, many tasks can be solved in science and technics with the help of FOSs. They are useful for measuring temperature [26][27][28], deformation [29,30], rotation speed [31], acceleration [32,33], vibration [34,35], liquid level [36,37], and other parameters [38][39][40][41][42][43][44][45]. Separately, it is worth highlighting the ability of optical fiber to register acoustic vibrations in various environments [46][47][48], as well as vibrations of various objects and mechanisms [49][50][51], which forms the basis of acoustic diagnostics of technical objects, in particular, power plants, where non-invasive monitoring of the state of individual units is required, including GTUs used in GT engines, liquid rocket engines, and gas compressor stations.…”

Algorithm for assessing the technical condition of Aircraft structures using a Control System on Fiber Optic Sensors

“…With this approach to operation, standard methods for writing off a resource are not the optimal approach to assessing their condition. In recent years, the approach to the operation of aircraft in the current state [1] has become increasingly popular, the implementation of which requires the development of both technical condition monitoring systems, including the further development of technologies such as HUMS [2], and the introduction of new methods for assessing technical condition based on a large array of data from sensors embedded in the structure or installed on its surface. Over the past two decades, polymer composite materials (PCM) have become widely used in aircraft structures.…”

“…One of the most promising technologies for the implementation of control systems is fiber-optic sensors [3], due to the following advantages: 1. lack of electromagnetic sensitivity, 2. small size, 3. high sensitivity to the measured value, 3. no restrictions on the length of the fiber optical cable. Due to its advantages, fiber-optic sensors can be installed both on the surface of structures and embedded between PCM layers at the stage of fabrication of a structure with the aim of subsequent monitoring of its technical condition in operation [1]. In addition, using various physical principles of data recording, fiber-optic sensors can be used to monitor a wide range of various parameters of external influence, including: deformation, temperature, shock, vibration, acoustic emission, etc.…”