Research on static and dynamic strain monitoring for a certain spacecraft based on optical fiber grating sensor

摘要

One of the main tasks of the spacecraft is to carry out long-term spaceflights, science research and other activities. For different scientific applications, we need to know about the strain of cabin for evaluating the health condition of spacecraft. Here, two factors mainly work. One is the temperature, and another is refueling operations. For the latter, it is necessary to carry out the unscheduled refueling for life or experiments. The advantages of FBG sensor is suitable for application in aircraft. This paper shows the detection of static and dynamic strain under in flight environment of a certain aircraft by FBG sensors and resistance strain gauge. In the static strain detection, taking the resistance strain gauge as measurement standard, FBG sensors have a large measurement error. For example, for testing position "A", the initial error is around 28.13%. After thermal compensation of bulkhead for FBG sensors, error value reduces to 5.95%. After thermal compensation of bulkhead both for FBG sensors and resistance strain gauge, error value reduces to 0.36%. In the dynamic strain measurement, the impact test of different positions in the same height and different heights on the same position for the bulkhead is carried out. The results show that the two measurement methods are accordant in high frequency and able to identify impact signals effectively. It is very important for structure prediction and health assessment.