Abstract: The flexible solar array of a space station has a large spread area and a center of mass far away from the body of the space station. In order to obtain its dynamic characteristics accurately, the modal test of the flexible solar array with 5 m×8 m is carried out in the inverted state and a digital camera vibration measuring system is designed. Based on the method of 3D point tracing, the process of camera calibration, image acquisition, information extraction and 3D vibration data acquisition is realized, and the modal parameters of the solar array are obtained by modal identification. Considering the influence of air and gravity, the finite element model of solar array is established, and the 3D point tracing identification results are compared with the traditional modal test results based on the Keenz laser displacement sensor and simulation analysis results. The accuracy of the modal test method based on the digital camera technology is verified, which lays a foundation for the on-orbit modal identification of the flexible solar array of a space station.

Key words: Flexible solar array, Image feature tracking, Modal identification