A Method for Operational Modal Parameters Identification of Attitude and Orbit Control Engine

The attitude and orbit control engine is often subjected to strong noise interference in actual working conditions, leading to difficulties in identifying operational modal parameters and low accuracy of results. This greatly limits the engineering application effectiveness of operational modal analysis (OMA). In allusion to the problem above, this paper takes the attitude and orbit control engine as the research object and conducts random vibration test on the structure. Compared with traditional experimental modal analysis (EMA), the test provides response data that is more in line with the actual operating conditions. Then, the operational modal parameters identification algorithm based on multivariate statistical analysis is applied to identify the modal parameters of the structure, and the identified results are compared with the experimental modal analysis results. The results show that this method can identify the modal parameters of attitude and orbit control engine accurately. Finally, the software platform development was carried out to establish a standardized process and system, providing technical support for the identification of operational modal parameters of such engineering structures.