Abstract: In view of the local non-linear characteristics of the new hold-down and release mechanism for satellites, a local non-linear structure model was proposed. The forcedisplacement curves of the local non-linear structure were obtained by simulating the loading. Based on the actual working conditions of the structure, the selection principle of equivalent stiffness load and displacement limit of the structure was defined, and the equivalent stiffness value interval of the structure was solved. Finally, an interval uncertainty analysis was carried out for the dynamic characteristics of the antenna. The results of the analysis are in good agreement with the test results. The basic frequency error of the antenna is less than 10%, meeting the requirements of engineering application. The validity of the analysis method was illustrated. The interval analysis method of equivalent stiffness of local nonlinear structure proposed in this paper provides a solution for the nonlinear dynamic analysis of new hold-down and release mechanism of satellite antenna, and also provides a reference for other local nonlinear structural dynamic analysis.

Key words: hold-down and release mechanism, nonlinear, equivalent stiffness, uncertainty, dynamic analysis