Abstract: Most spacecrafts vibrate when subjected to alternating heat and cold during operation, which causes the spacecraft failing to work properly or even damage. At present, there are more theoretical researches on this phenomenon called thermally induced vibration in the industry, and fewer experimental studies. This is mainly due to the lack of high precision measurement methods. Based on the common thermal vibration model, the structure of the flexible boom is built in this paper, and fiber grating strain sensor and fiber Fabry Perot acceleration sensor are used to measure its thermal vibration characteristics. The experimental results show that the flexible boom has thermally induced vibration under the radiation of the heat source. The strain and acceleration of the flexible boom obtained by the fiber grating strain sensor and the fiber acceleration sensor are consistent with the theoretical analysis. The proposed sensor can accurately measure the thermally induced vibration without affecting the structural characteristics.

Key words: thermal vibration, high precision, fiber optic sensor, strain, acceleration